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Sample records for emulsion experiment nucleus-nucleus

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

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

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

  2. Observation of direct hadronic pairs in nucleus-nucleus collisions in JACEE emulsion chambers

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    In a number of high energy ( or = 1 TeV/amu) nucleus-nucleus collisions observed in Japanese-American Cooperative Emulsion Experiment (JACEE) emulsion chambers, nonrandom spatial association of produced charged particles, mostly hadronic pairs, are observed. Similar narrow pairs are observed in about 100 events at much low energy (20 to 60 GeV/amu). Analysis shows that 30 to 50% of Pair abundances are understood by the Hambury-Brown-Twiss effect, and the remainder seems to require other explanations.

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

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1988-01-01

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

  4. Meson multiplicity versus energy in relativistic nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Atwater, T. W.; Freier, P. S.

    1986-01-01

    A systematic study of meson multiplicity as a function of energy at energies up to 100 GeV/u in nucleus-nucleus collisions has been made, using cosmic-ray data in nuclear emulsion. The data are consistent with simple nucleon-nucleon superposition models. Multiplicity per interacting nucleon in AA collisions does not appear to differ significantly from pp collisions.

  5. High energy nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Wosiek, B.

    1986-01-01

    Experimental results on high energy nucleus-nucleus interactions are presented. The data are discussed within the framework of standard super-position models and from the point-of-view of the possible formation of new states of matter in heavy ion collisions.

  6. Azimuthal correlation and collective behavior in nucleus-nucleus collisions

    SciTech Connect

    Mali, P.; Mukhopadhyay, A. Sarkar, S.; Singh, G.

    2015-03-15

    Various flow effects of nuclear and hadronic origin are investigated in nucleus-nucleus collisions. Nuclear emulsion data collected from {sup 84}Kr + Ag/Br interaction at an incident energy of 1.52 GeV per nucleon and from {sup 28}Si + Ag/Br interaction at an incident energy of 14.5 GeV per nucleon are used in the investigation. The transverse momentum distribution and the flow angle analysis show that collective behavior, like a bounce-off effect of the projectile spectators and a sidesplash effect of the target spectators, are present in our event samples. From an azimuthal angle analysis of the data we also see a direct flow of the projectile fragments and of the produced charged particles. On the other hand, for both data samples the target fragments exhibit a reverse flow, while the projectile fragments exhibit an elliptic flow. Relevant flow parameters are measured.

  7. Average transverse momentum and energy density in high-energy nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

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

    1986-01-01

    Emulsion chambers were used to measure the transverse momenta of photons or pi(0) mesons produced in high-energy cosmic-ray nucleus-nucleus collisions. A group of events having large average transverse momenta has been found which apparently exceeds the expected limiting values. Analysis of the events at early interaction times, of the order of 1 fm/c, indicates that the observed transverse momentum increases with both rapidity density and energy density.

  8. Single nucleon emission in relativistic nucleus-nucleus reactions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.

    1992-01-01

    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 cross sections and compared to the total experimental cross sections. Good agreement is found thereby resolving some of the earlier noted discrepancies. A detailed comparison to the recent work of Benesh, Cook, and Vary is made for both the impact parameter and the nuclear cross section. Good agreement is obtained giving an independent confirmation of the parameterized formulas developed by those authors.

  9. Onset of deconfinement in nucleus-nucleus collisions

    SciTech Connect

    Gazdzicki, M.; Gorenstein, M. I.; Seyboth, P.

    2012-05-15

    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.

  10. Higgs-boson production in nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  11. Higgs-Boson Production in Nucleus-Nucleus Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1989-01-01

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

  13. Emulsion Chamber Technology Experiment (ECT)

    NASA Technical Reports Server (NTRS)

    Gregory, John C.; Takahashi, Yoshiyuki

    1996-01-01

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

  14. The emulsion chamber technology experiment

    NASA Technical Reports Server (NTRS)

    Gregory, John C.

    1992-01-01

    Photographic emulsion has the unique property of recording tracks of ionizing particles with a spatial precision of 1 micron, while also being capable of deployment over detector areas of square meters or 10's of square meters. Detectors are passive, their cost to fly in Space is a fraction of that of instruments of similar collecting. A major problem in their continued use has been the labor intensiveness of data retrieval by traditional microscope methods. Two factors changing the acceptability of emulsion technology in space are the astronomical costs of flying large electronic instruments such as ionization calorimeters in Space, and the power and low cost of computers, a small revolution in the laboratory microscope data-taking. Our group at UAH made measurements of the high energy composition and spectra of cosmic rays. The Marshall group has also specialized in space radiation dosimetry. Ionization calorimeters, using alternating layers of lead and photographic emulsion, to measure particle energies up to 10(exp 15) eV were developed. Ten balloon flights were performed with them. No such calorimeters have ever flown in orbit. In the ECT program, a small emulsion chamber was developed and will be flown on the Shuttle mission OAST-2 to resolve the principal technological questions concerning space exposures. These include assessments of: (1) pre-flight and orbital exposure to background radiation, including both self-shielding and secondary particle generation; the practical limit to exposure time in space can then be determined; (2) dynamics of stack to optimize design for launch and weightlessness; and (3) thermal and vacuum constraints on emulsion performance. All these effects are cumulative and affect our ability to perform scientific measurements but cannot be adequately predicted by available methods.

  15. Performance of automatic scanning microscope for nuclear emulsion experiments

    NASA Astrophysics Data System (ADS)

    Güler, A. Murat; Altınok, Özgür

    2015-12-01

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  16. Performance of automatic scanning microscope for nuclear emulsion experiments

    SciTech Connect

    Güler, A. Murat; Altınok, Özgür

    2015-12-31

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  17. Dynamical nucleus-nucleus potential at short distances

    SciTech Connect

    Jiang Yongying; Wang Ning; Li Zhuxia; Scheid, Werner

    2010-04-15

    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.

  18. Higgs and Particle Production in Nucleus-Nucleus Collisions

    NASA Astrophysics Data System (ADS)

    Liu, Zhe

    We apply a diagrammatic approach to study Higgs boson, a color-neutral heavy particle, pro- duction in nucleus-nucleus collisions in the saturation framework without quantum evolution. We assume the strong coupling constant much smaller than one. Due to the heavy mass and colorless nature of Higgs particle, final state interactions are absent in our calculation. In order to treat the two nuclei dynamically symmetric, we use the Coulomb gauge which gives the appropriate light cone gauge for each nucleus. To further eliminate initial state interactions we choose specific prescriptions in the light cone propagators. We start the calculation from only two nucleons in each nucleus and then demonstrate how to generalize the calculation to higher orders diagrammatically. We simplify the diagrams by the Slavnov-Taylor-Ward identities. The resulting cross section is factorized into a product of two Weizsacker-Williams gluon distributions of the two nuclei when the transverse momentum of the produced scalar particle is around the saturation momentum. To our knowledge this is the first process where an exact analytic formula has been formed for a physical process, involving momenta on the order of the saturation momentum, in nucleus-nucleus collisions in the quasi-classical approximation. Since we have performed the calculation in an unconventional gauge choice, we further confirm our results in Feynman gauge where the Weizsacker-Williams gluon distribution is interpreted as a transverse momentum broadening of a hard gluons traversing a nuclear medium. The transverse momentum factorization manifests itself in light cone gauge but not so clearly in Feynman gauge. In saturation physics there are two different unintegrated gluon distributions usually encountered in the literature: the Weizsacker-Williams gluon distribution and the dipole gluon distribution. The first gluon distribution is constructed by solving classical Yang-Mills equation of motion in the Mc

  19. Measurements of Quarkonium Polarization and Production versus Charged-Particle Multiplicity in p + p Collisions at √{ s} = 500 GeV in the STAR Experiment. The XXVth International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

    NASA Astrophysics Data System (ADS)

    Trzeciak, Barbara

    2016-12-01

    We report on the J/ψ production and polarization as a function of pT and xT, measured via the dielectron decay channel at mid-rapidity in p+p collisions at √{ s} = 500 GeV in the STAR experiment. The measured J/ψpT spectrum is in agreement with NRQCD and CGC+NRQCD predictions, while the J/ψ polarization shows a trend towards longitudinal polarization with increasing pT. In addition, first measurements of the J/ψ production as a function of charged-particle multiplicity are presented at √{ s} = 500 GeV. A strong correlation between the J/ψ yield and charged-particle multiplicity is observed with a hint of J/ψpT dependence.

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

    SciTech Connect

    Chessin, S.A.

    1983-05-01

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

  1. Classifiers for centrality determination in proton-nucleus and nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Altsybeev, Igor; Kovalenko, Vladimir

    2017-03-01

    Centrality, as a geometrical property of the collision, is crucial for the physical interpretation of nucleus-nucleus and proton-nucleus experimental data. However, it cannot be directly accessed in event-by-event data analysis. Common methods for centrality estimation in A-A and p-A collisions usually rely on a single detector (either on the signal in zero-degree calorimeters or on the multiplicity in some semi-central rapidity range). In the present work, we made an attempt to develop an approach for centrality determination that is based on machine-learning techniques and utilizes information from several detector subsystems simultaneously. Different event classifiers are suggested and evaluated for their selectivity power in terms of the number of nucleons-participants and the impact parameter of the collision. Finer centrality resolution may allow to reduce impact from so-called volume fluctuations on physical observables being studied in heavy-ion experiments like ALICE at the LHC and fixed target experiment NA61/SHINE on SPS.

  2. Nucleus-nucleus interaction above several hundred GeV/n

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Stein, Daniel J.; Spera, Frank J.

    1992-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Contreras, Carlos; Levin, Eugene; Meneses, Rodrigo

    2013-04-01

    In this paper we solve the equation for nucleus-nucleus scattering in the BFKL Pomeron calculus, suggested by Braun [1-3]. We find these solutions analytically at high energies as well as numerically in the entire region of energies inside the saturation region. The semi-classical approximation is used to select out the infinite set of the parasite solutions. The nucleus-nucleus cross sections at high energy are estimated and compared with the Glauber-Gribov approach. It turns out that the exact formula gives the estimates that are very close to the ones based on Glauber-Gribov formula which is important for the practical applications.

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

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

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

  6. Nucleus-nucleus collisions and the nuclear equation of state

    NASA Astrophysics Data System (ADS)

    Keane, Declan

    An analysis was made of existing experimental data from the Bevalac streamer chamber and from the Kent state neutron flow experiment 848H; transport model were compared with these data and with published results from other experiments. Future Bevelac experiment were developed, with particular emphasis on the EOS Time Projection Chamber (TPC). The PI is spokesperson for one of three beam-time proposals for the first round of experiments at the EOS TPC, to be considered by the Bevalac PAC in June 1990. Planned activities for the coming budget period include a continuation of strong emphasis on the TPC, and the initiation of participation in a planned RHIC experiment.

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

    NASA Astrophysics Data System (ADS)

    Li, Bao-An; Natowitz, Joseph B.

    2013-03-01

    The 11th International Conference on Nucleus-Nucleus Collisions (NN2012) was held from 27 May to 1 June 2012, in San Antonio, Texas, USA. It was jointly organized and hosted by The Cyclotron Institute at Texas A&M University, College Station and The Department of Physics and Astronomy at Texas A&M University-Commerce. Among the approximately 300 participants were a large number of graduate students and post-doctoral fellows. The Keynote Talk of the conference, 'The State of Affairs of Present and Future Nucleus-Nucleus Collision Science', was given by Dr Robert Tribble, University Distinguished Professor and Director of the TAMU Cyclotron Institute. During the conference a very well-received public lecture on neutrino astronomy, 'The ICEcube project', was given by Dr Francis Halzen, Hilldale and Gregory Breit Distinguished Professor at the University of Wisconsin, Madison. The Scientific program continued in the general spirit and intention of this conference series. As is typical of this conference a broad range of topics including fundamental areas of nuclear dynamics, structure, and applications were addressed in 42 plenary session talks, 150 parallel session talks, and 21 posters. The high quality of the work presented emphasized the vitality and relevance of the subject matter of this conference. Following the tradition, the NN2012 International Advisory Committee selected the host and site of the next conference in this series. The 12th International Conference on Nucleus-Nucleus Collisions (NN2015) will be held 21-26 June 2015 in Catania, Italy. It will be hosted by The INFN, Laboratori Nazionali del Sud, INFN, Catania and the Dipartimento di Fisica e Astronomia of the University of Catania. The NN2012 Proceedings contains the conference program and 165 articles organized into the following 10 sections 1. Heavy and Superheavy Elements 2. QCD and Hadron Physics 3. Relativistic Heavy-Ion Collisions 4. Nuclear Structure 5. Nuclear Energy and Applications of

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

    NASA Technical Reports Server (NTRS)

    Khan, Ferdous; Townsend, Lawrence W.

    1993-01-01

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

  9. Sensitivity of cross sections for elastic nucleus-nucleus scattering to halo nucleus density distributions

    SciTech Connect

    Alkhazov, G. D.; Sarantsev, V. V.

    2012-12-15

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

  10. Development of new-type nuclear emulsion for a balloon-borne emulsion gamma-ray telescope experiment

    NASA Astrophysics Data System (ADS)

    Ozaki, K.; Aoki, S.; Kamada, K.; Kosaka, T.; Mizutani, F.; Shibayama, E.; Takahashi, S.; Tateishi, Y.; Tawa, S.; Yamada, K.; Kawahara, H.; Otsuka, N.; Rokujo, H.

    2015-12-01

    This study reports a new-type of nuclear emulsion that improves the track-finding efficiency of charged particle detection. The emulsion is applied to the GRAINE project, a balloon-borne experiment that observes cosmic γ-rays through an emulsion γ-ray telescope. The new emulsion film dramatically improves the detection efficiency for γ-rays. The nuclear emulsion gel and films for the second GRAINE balloon-borne experiment (GRAINE-2015) were fully self-produced by ourselves. New handling methods for the novel emulsion film have also been developed. Over time, the stored films gradually become desensitized to minimum ionizing particles, but the original sensitivity can be restored by a resetting process. Moreover, the fading of latent images can be arrested by a drying process. To sensitize the new-type films and avoid their fading, emulsion preprocessing was applied immediately prior to GRAINE-2015. A balloon flight with the emulsion γ-ray telescope was successfully completed in Australia on 12th May 2015. By scanning with automated optical microscopes and analyzing the penetrated tracks, we confirmed the high track-finding efficiency (97%) of the mounted films. The analysis of γ-ray event detection, aims at detecting Vela pulsar, is in progress.

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

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Blattnig, Steve R.

    2008-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

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

  13. Fermi-motion effect on the intermediate energy nucleus-nucleus collision

    NASA Astrophysics Data System (ADS)

    Fan, G. W.; Kong, W. Y.; Han, T. F.; Li, X. C.; Ma, J. B.; Sheng, Z. Q.; Shi, G. Z.; Tian, F.; Wang, J.; Zhang, C.

    2016-11-01

    The Glauber model is modified with the Fermi-motion effect in the calculation of elastic differential cross-sections and momentum distributions of a fragment from mother nucleus. Different reaction systems at low energies are calculated with the modified Glauber model. It is found that calculations including the Fermi-motion provide a better prescription relating the model to a proper nuclear density distribution by comparing with the experimental data. On the basis of the studies, the influence of the correction on the extracted nuclear radius is quantified. The results further confirm the importance of the Fermi-motion in the nucleus-nucleus collision reactions at low energies.

  14. Nuclear mean field and double-folding model of the nucleus-nucleus optical potential

    NASA Astrophysics Data System (ADS)

    Khoa, Dao T.; Phuc, Nguyen Hoang; Loan, Doan Thi; Loc, Bui Minh

    2016-09-01

    Realistic density dependent CDM3Yn versions of the M3Y interaction have been used in an extended Hartree-Fock (HF) calculation of nuclear matter (NM), with the nucleon single-particle potential determined from the total NM energy based on the Hugenholtz-van Hove theorem that gives rise naturally to a rearrangement term (RT). Using the RT of the single-nucleon potential obtained exactly at different NM densities, the density and energy dependence of the CDM3Yn interactions was modified to account properly for both the RT and observed energy dependence of the nucleon optical potential. Based on a local density approximation, the double-folding model of the nucleus-nucleus optical potential has been extended to take into account consistently the rearrangement effect and energy dependence of the nuclear mean-field potential, using the modified CDM3Yn interactions. The extended double-folding model was applied to study the elastic 12C+12C and 16O+12C scattering at the refractive energies, where the Airy structure of the nuclear rainbow has been well established. The RT was found to affect significantly the real nucleus-nucleus optical potential at small internuclear distances, giving a potential strength close to that implied by the realistic optical model description of the Airy oscillation.

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

    NASA Technical Reports Server (NTRS)

    Meyers, J. E.

    1972-01-01

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

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

    SciTech Connect

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

    2009-12-15

    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.

  17. Experimental evidence and the Landau-Zener promotion in nucleus-nucleus collisions

    SciTech Connect

    Cindro, N.; Freeman, R.M.; Haas, F.

    1986-04-01

    Recent data from C+O collisions are analyzed in terms of the Landau-Zener promotion in nuclei. Evidence for the presence of this mechanism in nuclear collisions is of considerable interest, since it provides a signature of single-particle orbitals in molecular-type potentials and, at the same time, paves the way to a microscopic understanding of the collision dynamics, in particular of the energy dissipation rate. The analyzed data are of two types: integrated cross sections and angular distributions of inelastically scattered particles. The first set of data shows structure qualitatively consistent with recent calculations of the Landau-Zener effect; for this set of data no other reasonable explanation is presently available. The second set of data, while consistent with the presence of the Landau-Zener promotion, is examined in terms of other possible explanations too. The combined data show evidence favoring the presence of the Landau-Zener promotion in nucleus-nucleus collisions.

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

    NASA Astrophysics Data System (ADS)

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

    2011-10-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

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

  20. Quantitative analysis of the fusion cross sections using different microscopic nucleus-nucleus interactions

    NASA Astrophysics Data System (ADS)

    Adel, A.; Alharbi, T.

    2017-01-01

    The fusion cross sections for reactions involving medium and heavy nucleus-nucleus systems are investigated near and above the Coulomb barrier using the one-dimensional barrier penetration model. The microscopic nuclear interaction potential is computed by four methods, namely: the double-folding model based on a realistic density-dependent M3Y NN interaction with a finite-range exchange part, the Skyrme energy density functional in the semiclassical extended Thomas-Fermi approximation, the generalized Proximity potential, and the Akyüz-Winther interaction. The comparison between the calculated and the measured values of the fusion excitation functions indicates that the calculations of the DFM give quite satisfactory agreement with the experimental data, being much better than the other methods. New parameterized forms for the fusion barrier heights and positions are presented. Furthermore, the effects of deformation and orientation degrees of freedom on the distribution of the Coulomb barrier characteristics as well as the fusion cross sections are studied for the reactions 16 O + 70 Ge and 28 Si + 100 Mo. The calculated values of the total fusion cross sections are compared with coupled channel calculations using the code CCFULL and compared with the experimental data. Our results reveal that the inclusion of deformations and orientation degrees of freedom improves the comparison with the experimental data.

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

    NASA Technical Reports Server (NTRS)

    Cheung, Wang K.; Norbury, John W.

    1994-01-01

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

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

    SciTech Connect

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

    2013-03-25

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

  3. Dynamics of strange, charm and high momentum hadrons in relativistic nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Cassing, W.; Gallmeister, K.; Bratkovskaya, E. L.; Greiner, C.; Stöcker, H.

    2004-07-01

    We investigate hadron production and attenuation of hadrons with strange and charm quarks (or antiquarks) as well as high transverse momentum hadrons in relativistic nucleus-nucleus collisions from 2 A GeV to 21.3 A TeV within two independent transport approaches (UrQMD and HSD). Both transport models are based on quark, diquark, string and hadronic degrees of freedom, but do not include any explicit phase transition to a quark-gluon plasma. From our dynamical calculations we find that both models do not describe the maximum in the K+/ π+ ratio at 20-30 A GeV in central Au+Au collisions found experimentally, though the excitation functions of strange mesons are reproduced well in HSD and UrQMD. Furthermore, the transport calculations show that the charmonium recreation by D+ D¯→J/Ψ+ meson reactions is comparable to the dissociation by ‘comoving’ mesons at RHIC energies contrary to SPS energies. This leads to the final result that the total J/ Ψ suppression as a function of centrality at RHIC should be less than the suppression seen at SPS energies where the ‘comover’ dissociation is substantial and the backward channels play no role. Furthermore, our transport calculations-in comparison to experimental data on transverse momentum spectra from pp, d+Au and Au+Au reactions-show that pre-hadronic effects are responsible for both the hardening of the hadron spectra for low transverse momenta (Cronin effect) as well as the suppression of high pT hadrons. The mutual interactions of formed hadrons are found to be negligible in central Au+Au collisions at s=200 GeV for p T≥6 GeV/c and the sizeable suppression seen experimentally is attributed to a large extent to the interactions of ‘leading’ pre-hadrons with the dense environment.

  4. Search for ντ Interactions with the Nuclear Emulsion Films of the Opera Experiment

    NASA Astrophysics Data System (ADS)

    Pupilli, Fabio

    2013-11-01

    The OPERA experiment aims at measuring the νμ → ντ oscillation through the ντ appearance in an almost pure νμ beam (CNGS). For the direct identification of the short-lived τ lepton, produced in ντ CC interactions, a micrometric detection resolution is needed. Therefore the OPERA detector makes use of nuclear emulsion films, the highest spatial resolution tracking device, combined with lead plates in an emulsion cloud chamber (ECC) structure called `brick'. In this paper the nuclear emulsion analysis chain is reported; the strategy and the algorithms set up will be described together with their performances.

  5. Fat emulsion for intravenous administration: clinical experience with intralipid 10%.

    PubMed Central

    Hansen, L M; Hardie, B S; Hidalgo, J

    1976-01-01

    A 10% soybean oil emulsion (Intralipid 10%), used extensively in Europe for intravenous alimentation, has now been clinically evaluated in the United States. Controlled studies have shown that the soybean oil emulsion can be substituted for glucose to supply one-third to two-thirds of the total calories, and can be administered peripherally without significant vein irritation. Essential fatty acid deficiencies, frequently encountered in patients dependent on parenteral alimentation with fat-free solutions, are prevented and corrected by use of this preparation. Data on long-term tolerance to Intralipid 10% infusions are presented for 292 patients treated for more than 6,000 patient days. The soybean oil emulsion was usually well tolerated. Side effects were reported in two of 133 adults and 12 of 159 pediatric patients. PMID:820291

  6. Photographic Emulsions in the OPERA Long Baseline Experiment Status and First Results

    NASA Astrophysics Data System (ADS)

    Meisel, Frank W.

    2010-04-01

    The OPERA experiment (Oscillation Project with Emulsion tRacking Apparatus) has been designed to confirm the neutrino oscillation hypothesis by direct observation of the tau neutrino appearance coming out of a (almost) pure muon neutrino beam. The beam is extracted from the SPS at CERN towards the Gran Sasso Underground Laboratory, the location of OPERA, 730km afar. In order to detect the leptonic tau decays, the vertex detector needs a spatial resolution of the order of micrometers. Nuclear emulsion films are the only detector materials capable of fulfilling this tight condition. In addition, emulsion scanning techniques have been significantly improved during the last recent neutrino experiments. This article is going to review the status of the detector, the neutrino beam properties, the first results from the 2008 run and the neutrino event analyses putting special emphasis on the emulsion detection technique.

  7. Double hypernuclei experiment with hybrid emulsion method (J-PARC E07)

    NASA Astrophysics Data System (ADS)

    Ekawa, Hiroyuki; J-APRC E07 Collaboration

    2014-09-01

    Double hypernuclei are important probes to study the system with strangeness -2. In order to search for double hypernuclei, an upgrade experiment is planned at J-PARC K1.8 beam line. In the experiment, the KURAMA spectrometer system will detect Ξ- production in the (K- ,K+) reaction on a diamond target. SSDs located the upstream and the downstream of emulsion plates will record Ξ- tracks which flight toward emulsion plates precisely. Tracks in SSDs and emulsion will be automatically connected by a hybrid method. Discoveries of more than 10 new double hypernuclear species are expected, which enable us to discuss binding energy in terms of mass number dependence. On the other hand, we will also observe X rays from Ξ- atoms with a Germanium detector array installed close to the emulsion by tagging Ξ-stopped events. This will be the first measurement in the world and give information on the Ξ-potential shape at the nuclear surface region. Emulsion production has been completely done and a test experiment for some detectors of KURAMA spectrometer was carried out. In this talk, physics motivation and current status of the J-PARC E07 experiment will be reported.

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

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

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

  9. GRAINE project: The first balloon-borne, emulsion gamma-ray telescope experiment

    NASA Astrophysics Data System (ADS)

    Takahashi, Satoru; Aoki, Shigeki; Kamada, Keiki; Mizutani, Saki; Nakagawa, Ryo; Ozaki, Keita; Rokujo, Hiroki

    2015-04-01

    The GRAINE project (Gamma-Ray Astro-Imager with Nuclear Emulsion) has been developed for the observation of cosmic γ-rays in the energy range 10 MeV-100 GeV with a precise (0.08°} at 1-2 GeV), polarization-sensitive, large-aperture-area (˜10 m^2) emulsion telescope by repeated long-duration balloon flights. In 2011, the first balloon-borne experiment was successfully performed with a 12.5 × 10cm^2 aperture area and 4.6 hour flight duration for a feasibility and performance test. Systematic detection, energy reconstruction, and timestamping of γ-ray events were performed across the whole area of the emulsion film, up to 45° incident zenith angle, down to 50 MeV γ-ray energy, with 97% detection reliability, 0.2 sec timestamp accuracy, and 98% timestamp reliability. A γ-ray data checking and calibration method was created using the γ-rays produced in the converter. We measured the atmospheric γ-ray flux in the energy range 50-300 MeV and obtained a first understanding of the cosmic γ-ray background. By combining the attitude data, we established a procedure for determining the γ-ray arrival direction in celestial coordinates. The first flight of the balloon-borne emulsion telescope confirmed its potential as a high-performance cosmic γ-ray detector.

  10. 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)

    Zapp, Edward Neal

    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.

  11. K + production in a cascade model for high-energy nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Cugnon, J.; Lombard, R. M.

    1984-07-01

    The K + production is studied for the p + NaF, Ne + NaF, Ne + Pb systems at 2.1 GeV/ A in the frame of a 3-dimensional cascade model. Owing to the small elementary production cross sections, the K + production is calculated perturbatively. Two kinds of production processes are introduced: baryon-baryon collisions leading to three-particle final states, and pion-nucleon collisions leading to two-body final states. The time evolution of the two processes is studied. The integrated K + cross sections are in good agreement with the experimental data. The contribution of the πN induced mechanism is of the order of 25% for Ne + NaF, but increases with the size of the system. Scaling properties are discussed. A simple rescattering model is used to calculate the invariant cross section for the Ne + NaF case. Good agreement with experiment is obtained, except at forward angles.

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

    SciTech Connect

    Cap, T.; Siwek-Wilczynska, K.; Wilczynski, J.

    2011-05-15

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

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

  14. PREFACE: Hot Quarks 2014: Workshop for young scientists on the physics of ultrarelativistic nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    2015-05-01

    The 6th edition of the Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions (Hot Quarks 2014) was held in Las Negras, Spain from 21-28 September 2014. Following the traditions of the conference, this meeting gathered more than 70 participants in the first years of their scientific careers. The present issue contains the proceedings of this 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. Recent theoretical developments were also extensively discussed as well as the perspectives for future facilities such as the Facility for Antiproton and Ion Research (FAIR) at Darmstadt and the Electron-Ion Collider at Brookhaven. 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 2014 Conference, who supported the authors of this volume: Brookhaven National Laboratory (USA), CPAN (Spain), Czech Science Foundation (GACR) under grant 13-20841S (Czech Republic), European Laboratory for Particle Physics CERN (Switzerland), European Research Council under grant 259612 (EU), ExtreMe Matter Institute EMMI (Germany), Helmholtz Association and GSI under grant VH-NG-822, Helmholtz International Center for FAIR (Germany), National Science Foundation under grant No.1359622 (USA), Nuclear Physics Institute ASCR (Czech Republic), Patronato de la Alhambra y Generalife (Spain) and the Universidad de Granada (Spain). Javier López Albacete, Universidad de Granada (Spain) Jana Bielcikova, Nuclear Physics Inst. and Academy of Sciences (Czech Republic) Rainer J. Fries, Texas A&M University (USA) Raphaël Granier de Cassagnac, CNRS-IN2P3 and École polytechnique (France

  15. Two-dimensional plastic flow of foams and emulsions in a channel: experiments and simulations

    NASA Astrophysics Data System (ADS)

    Sbragaglia, Mauro; Andrea Scagliarini Collaboration; Benjamin Dollet Collaboration

    2015-11-01

    In order to understand the flow profiles of complex fluids, a crucial issue concerns the emergence of spatial correlations among plastic rearrangements exhibiting cooperativity flow behaviour at the macroscopic level. In this paper, the rate of plastic events in a Poiseuille flow is experimentally measured on a confined foam in a Hele-Shaw geometry. The correlation with independently measured velocity profiles is quantified by looking at the relationship between the localisation length of the velocity profiles and the localisation length of the spatial distribution of plastic events. To complement the cooperativity mechanisms studied in foam with those of other soft glassy systems, we compare the experiments with simulations of dense emulsions based on the lattice Boltzmann method, which are performed both with and without wall friction. Finally, unprecedented results on the distribution of the orientation of plastic events show that there is a non-trivial correlation with the underlying local shear strain. These features, not previously reported for a confined foam, lend further support to the idea that cooperativity mechanisms, originally invoked for concentrated emulsions (Goyon et al., Nature, vol. 454, 2008, pp. 84-87), have parallels in the behaviour of other soft glassy ma ERC Grant n.279004-DROEMU

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

    SciTech Connect

    Plasil, F.; Awes, T.C.; Baktash, C.; Ferguson, R.L.; Lee, I.Y.; Saini, S.; Tincknell, M.L.; Young, G.R. ); Obenshain, F.E.; Sorensen, S.P. Tennessee Univ., Knoxville, TN ); 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

    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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  18. Drop impact experiment as a model experiment to investigate the role of oil-in-water emulsions in controlling the drop size distribution of an agricultural spray

    NASA Astrophysics Data System (ADS)

    Vernay, Clara; Ramos, Laurence; Ligoure, Christian; Douzals, Jean-Paul; Goyal, Rajesh; Castaing, Jean-Christophe

    2014-11-01

    Agricultural spraying involves atomizing a liquid stream through a hydraulic nozzle forming a liquid sheet, which is then destabilized into droplets. Solution adjuvants as dilute oil-in-water emulsions are known to influence the spray drop size distribution. To elucidate the mechanisms causing the changes on the drop size distribution, we investigate the influence of emulsions on the destabilization mechanisms of liquid sheets. Model laboratory experiments based on the collision of a liquid drop on a small target are used to produce and visualize liquid sheets. With emulsion, the sheet is destabilized by the nucleation of holes in the sheet that perforate it during its expansion. The physico-chemical parameters of the emulsion, such as the concentration and the emulsion drop size distribution, are varied to rationalize their influence on the destabilization mechanisms. The results obtained with the drop impact experiments are compared to the measurement of the spray drop size distribution. The very good correlation between the number of nucleation events and the volume fraction of small drops in the spray suggests that experiments on liquid sheet are appropriate model experiments to gain an understanding of the physical mechanisms governing the spray drop size distribution.

  19. Optics laboratory experiments with laser-heated samples of crude oils and oil-in-water emulsions

    NASA Astrophysics Data System (ADS)

    Da Costa, Germán.

    2007-06-01

    The aim of the present paper is to describe incorporation of basic industrial research results into current University study programs in Physics and Optoelectronic Engineering. The Laboratory of Optics and Fluids (LOF) of University Simon Bolivar (USB) leads a research program on applications of Photonics technology in the Petroleum Industry. More precisely, the main research subject at the (LOF) is development of optical procedures allowing determination of conditions of stability of oil-in-water emulsions. In several countries (for example, Canada and Venezuela) there exist important reservoirs of heavy crude oils, whose high viscosity impede their transportation through pipelines. Therefore, emulsions of heavy oils in water were developed in order to allow their commercialization. Though those emulsions are stable in current environmental conditions, high temperature or velocity gradients frequently provoke their coalescence. In typical experiments conducted at the (LOF) temperature gradients are induced in oil-water emulsions and in crude oil samples by irradiation with a CW laser beam. In crude oil samples the strong dependence of the liquid surface tension and refractive index on the local liquid temperature gives rise to long-range deformation of the liquid free surface. The latter cited thus behaves as an interferometrically smooth liquid mirror, which gives rise in turn to phase and intensity variations in the reflected light beam. In emulsion samples the inhomogeneous heating gives rise to thermoconvective flow, which is clearly observed as a moving speckle pattern in the reflected light beam. These are typical phenomena of self-interaction of a laser beam incident upon a material medium. In the present paper we discuss these optical phenomena, first studied in a basic research context, from an educational viewpoint.

  20. Intravenous lipid emulsion as antidote: a summary of published human experience.

    PubMed

    Cave, Grant; Harvey, Martyn; Graudins, Andis

    2011-04-01

    Intravenous lipid emulsion (ILE) has been demonstrated to be effective in amelioration of cardiovascular and central nervous system sequelae of local-anaesthetic and non-local-anaesthetic drug toxicity in animal models. Sequestration of lipophilic toxins to an expanded plasma lipid phase is credited as the predominant beneficial mechanism of action of ILE. Systematic review of published human experience is however lacking. We determined to report a comprehensive literature search of all human reports of ILE application in drug poisoning. Forty-two cases of ILE use (19 local-anaesthetic, 23 non-local-anaesthetic) were identified, with anecdotal reports of successful resuscitation from cardiovascular collapse and central nervous system depression associated with ILE administration in lipophilic toxin overdose. Although significant heterogeneity was observed in both agents of intoxication, and reported outcomes; case report data suggest a possible benefit of ILE in potentially life-threatening cardio-toxicity from bupivacaine, mepivacaine, ropivacaine, haloperidol, tricyclic antidepressants, lipophilic beta blockers and calcium channel blockers. Further controlled study and systematic evaluation of human cases is required to define the clinical role of ILE in acute poisonings.

  1. Event Analysis in Nuclear Emulsion for the E07 Experiment at J-PARC

    NASA Astrophysics Data System (ADS)

    Soe, Myint K.; Endo, Yoko; Hoshino, Kaoru; Ito, Hiroki; Itonaga, Kazunori; Kobayashi, Hidetaka; Tint, Khin T.; Kinbara, Shinji; Mishina, Akihiro; Yoshida, Junya; Nakazawa, Kazuma

    Hammer track events in nuclear emulsion were analyzed to measure the excitation energy of 8Be* (2+) nucleus. The kinetic energies of two alpha particles of hammer track events were obtained from their ranges with use of range-energy relation. The range-energy relation was calibrated by measuring the alpha particle tracks emitted from 212Po of Thorium decay series in the emulsion. From this calibration, we obtained density and shrinkage factor of the emulsion. The excitation energy and width of 8Be* (2+) nucleus were measured to be 3.39 ± 0.24 MeV and Γ = 1.22 ± 0.60 MeV respectively.

  2. Muon radiography in Russia with emulsion technique. First experiments future perspectives

    SciTech Connect

    Aleksandrov, A. B.; Bagulya, A. V.; Chernyavsky, M. M.; Konovalova, N. S.; Polukhina, N. G.; Shchedrina, T. V.; Starkov, N. I.; Tioukov, V. E.; Vladymyrov, M. S.; Managadze, A. K.; Roganova, T. M.; Orurk, O. I.; Zemskova, S. G.

    2015-12-31

    Cosmic ray muon radiography is a novel technique for imaging the internal structures of massive objects. It exploits the capability of high energy muons from cosmic-rays in order to obtain a density map of investigated object and trying to guess information on the variation in the density distribution. Nuclear emulsions are tracking detectors well suited to be employed in this context since they have an excellent angular resolution (few mrad), they are cheap, compact and robust, easily transportable, able to work in harsh environments, and do not require power supply. This work presents the first successful results in the field of muon radiography in Russia with nuclear emulsions.

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

    SciTech Connect

    Kirk, P.N.

    1990-12-01

    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)

  4. Intravenous Lipid Emulsion Therapy for Acute Synthetic Cannabinoid Intoxication: Clinical Experience in Four Cases

    PubMed Central

    Aksel, Gökhan; Güneysel, Özlem; Taşyürek, Tanju; Kozan, Ergül; Çevik, Şebnem Eren

    2015-01-01

    There is no specific antidote for intoxication with synthetic cannabinoids. In this case series, we considered the efficiency of intravenous lipid emulsion therapy in four cases, who presented to emergency department with synthetic cannabinoid (bonzai) intoxication. The first patient had a GCS of 3 and a left bundle branch block on electrocardiography. The electrocardiography revealed sinus rhythm with normal QRS width after the treatment. The second patient had bradycardia, hypotension, and a GCS of 14. After intravenous lipid emulsion therapy, the bradycardia resolved, and the patient's GCS improved to 15. The third patient presented with a GCS of 8, and had hypotension and bradycardia. After the treatment, not only did the bradycardia resolve, but also the GCS improved to 15. The fourth patient, whose electrocardiography revealed accelerated junctional rhythm, had a GCS of 13. The patient's rhythm was sinus after the treatment. Cardiovascular recovery was seen in all four cases, and neurological recovery was also seen in three of them. Based on the fact that intravenous lipid emulsion is beneficial in patients intoxicated with lipophilic drugs, unstable patients presenting to the emergency department with acute synthetic cannabinoid intoxication may be candidates for intravenous lipid emulsion treatment. PMID:26078891

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

    NASA Technical Reports Server (NTRS)

    Yodh, D. B.

    1977-01-01

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

  6. Electromagnetic probes of a pure-glue initial state in nucleus-nucleus collisions at energies available at the CERN Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Vovchenko, V.; Karpenko, Iu. A.; Gorenstein, M. I.; Satarov, L. M.; Mishustin, I. N.; Kämpfer, B.; Stoecker, H.

    2016-08-01

    Partonic matter produced in the early stage of ultrarelativistic nucleus-nucleus collisions is assumed to be composed mainly of gluons, and quarks and antiquarks are produced at later times. To study the implications of such a scenario, the dynamical evolution of a chemically nonequilibrated system is described by ideal (2+1)-dimensional hydrodynamics with a time dependent (anti)quark fugacity. The equation of state interpolates linearly between the lattice data for the pure gluonic matter and the lattice data for the chemically equilibrated quark-gluon plasma. The spectra and elliptic flows of thermal dileptons and photons are calculated for central Pb+Pb collisions at the CERN Large Hadron Collider energy of √{sN N}=2.76 TeV. We test the sensitivity of the results to the choice of equilibration time, including also the case where the complete chemical equilibrium of partons is reached already at the initial stage. It is shown that a suppression of quarks at early times leads to a significant reduction of the yield of the thermal dileptons, but only to a rather modest suppression of the pT distribution of direct photons. It is demonstrated that an enhancement of photon and dilepton elliptic flows might serve as a promising signature of the pure-glue initial state.

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  8. Search for anomalous C-jets in Chacaltaya emulsion chamber experiment

    NASA Technical Reports Server (NTRS)

    Kumano, H.

    1985-01-01

    Anomalous C-jets were measured in Chacaltaya emulsion chamber No.17. Measurement of 150 C-jets nuclear interactions occured in the target layer in the chamber itself with total visible energy greater than 5 TeV was completed. they are recorded in area of 11 sq m, corresponding to 17.1 sq m year exposure. Among them, seven events have no pinaught and two events are peculiar in that three showers out of four show abnormal cascade development. Two show remarkable characteristics indicating that they are coming from exotic interactions in the target layer. Illustrations of these events are presented and the thresholds of this type of event are discussed.

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  10. Clinical experience with intravenous lipid emulsion for drug-induced cardiovascular collapse.

    PubMed

    Geib, Ann-Jeannette; Liebelt, Erica; Manini, Alex F

    2012-03-01

    Intravenous lipid emulsion (ILE) is an emerging therapy for refractory cardiotoxicity due to lipid-soluble drugs. The purpose of this study was to assess survival to hospital discharge, effects on hemodynamic parameters, and adverse event occurrence for patients who were treated with ILE as part of the resuscitative effort for drug-induced cardiotoxicity. This is a multicenter retrospective chart review of inpatients at three tertiary referral medical centers receiving ILE for drug-induced cardiotoxicity between November 2007 and March 2009. Nine cases with drug-induced cardiovascular collapse, defined as cardiac arrest or refractory shock, were selected for review if patients received either bolus or infusion of ILE in any combination. No interventions were done. The main outcome measures were survival to hospital discharge, effect on hemodynamic parameters, and adverse event. Hemodynamic vital signs (heart rate, systolic blood pressure, diastolic blood pressure, calculated mean arterial pressure [MAP]) were measured before administration of ILE and up to five measurements (if available) were recorded after administration of ILE. Attribution of adverse events was determined by assignment of Naranjo adverse drug reaction (ADR) likelihood score (3) with adjudication of three medical toxicologists; disagreements were settled by majority consensus. Of nine cases identified based on inclusion criteria (three cardiac arrest, six refractory shock), five (55%) survived to hospital discharge. ILE regimens were bolus alone in five patients and bolus plus infusion in four patients. Hemodynamic trends in response to ILE demonstrated no difference in MAP immediately pre- and post-administration of ILE (p = NS). Administration of infusion (versus boluses alone) did not demonstrate a statistically significant improvement in MAP. Adverse events due to ILE therapy that were categorized as "possible" or "probable" based on Naranjo scores included lipemia, digit amputation, lung

  11. Static versus energy-dependent nucleus-nucleus potential for description of sub-barrier fusion dynamics of {}_{8}^{16}O+{}^{112,116,120}\\!\\!\\!\\!\\!\\!{}_{50}Sn reactions

    NASA Astrophysics Data System (ADS)

    Manjeet Singh, Gautam

    2015-11-01

    The static and energy-dependent nucleus-nucleus potentials are simultaneously used along with the Wong formula for exploration of fusion dynamics of {}816O+{}112,116,120{}50Sn reactions. The role of internal structure degrees of freedom of colliding pairs, such as inelastic surface vibrations, are examined within the context of coupled channel calculations performed using the code CCFULL. Theoretical calculations based on the static Woods-Saxon potential along with the one-dimensional Wong formula fail to address the fusion data of {}816O+{}112,116,120{}50Sn reactions. Such discrepancies can be removed if one uses couplings to internal structure degrees of freedom of colliding nuclei. However, the energy-dependent Woods-Saxon potential model (EDWSP model) accurately describes the sub-barrier fusion enhancement of {}816O+{}112,116,120{}50Sn reactions. Therefore, in sub-barrier fusion dynamics, energy dependence in the nucleus-nucleus potential governs barrier modification effects in a closely similar way to that of the coupled channel approach. Supported by Dr. D. S. Kothari Post-Doctoral Fellowship Scheme sponsored by University Grants Commission (UGC), New Delhi, India

  12. 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)

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

    2012-08-01

    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.

  13. On the halo events observed by Mount Fuji and Mount Kanbala Emulsion Chamber Experiments

    NASA Technical Reports Server (NTRS)

    Ren, J. R.; Kuang, H. H.; Huo, A. X.; Lu, S. L.; Su, S.; Wang, Y. X.; Xue, Y. G.; Wang, C. R.; He, M.; Zhang, N. J.

    1985-01-01

    The intensity of big gamma-ray families associated by halo is obtained from Mt. Fuji experiment (650 g/sq.cm. atmospheric depth) and Mt. Kanbala experiment (515 g/sq.cm.). The results are compared with Monte Carlo calculation based on several assumptions on interaction mechanisms and the primary cosmic ray composition. The results suggest more than 3 times lower proton abundance among primaries than that of 10 to the 12th to 10 to the 13th eV region within the framework of quasi-scaling model of multiple production.

  14. Results from NA60 experiment at the CERN SPS

    SciTech Connect

    Usai, G.; Cicalo, C.; De Falco, A.; Floris, M.; Masoni, A.; Puddu, G.; Serci, S.; Arnaldi, R.; Colla, A.; Cortese, P.; Ferretti, A.; Oppedisano, C.; Averbeck, R.; Drees, A.; Banicz, K.; Castor, J.; Devaux, A.; Force, P.; Manso, F.; Chaurand, B.

    2006-07-11

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

  15. 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)

    Anticic, T.; Baatar, B.; Barna, D.; Bartke, J.; Beck, H.; Betev, L.; Białkowska, H.; Blume, C.; Bogusz, M.; Boimska, B.; Book, J.; Botje, M.; Bunčić, P.; Cetner, T.; Christakoglou, P.; Chung, P.; Chvala, O.; Cramer, J. G.; Dinkelaker, P.; Eckardt, V.; Fodor, Z.; Foka, P.; Friese, V.; Gaździcki, 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.; Mrówczyński, St.; Nicolic, V.; Pálla, G.; Panagiotou, A. D.; Peryt, W.; Pluta, J.; Prindle, D.; Pühlhofer, F.; Renfordt, R.; Roland, C.; Roland, G.; Rybczyński, 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.; Utvić, M.; Varga, D.; Vassiliou, M.; Veres, G. I.; Vesztergombi, G.; Vranić, D.; Włodarczyk, Z.; Wojtaszek-Szwarc, A.

    2012-11-01

    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.

  16. Prospects of heavy and superheavy element production via inelastic nucleus-nucleus collisions - from 238U+238U to18O+254Es

    NASA Astrophysics Data System (ADS)

    Schädel, Matthias

    2016-12-01

    Multi-nucleon transfer reactions, frequently termed deep-inelastic, between heavy-ion projectiles and actinide targets provide prospects to synthesize unknown isotopes of heavy actinides and superheavy elements with neutron numbers beyond present limits. The 238U on 238U reaction, which revealed essential aspects of those nuclear reactions leading to surviving heavy nuclides, mainly produced in 3n and 4n evaporation channels, is discussed in detail. Positions and widths of isotope distributions are compared. It is shown, as a general rule, that cross sections peak at irradiation energies about 10% above the Coulomb barrier. Heavy target nuclei are essential for maximizing cross sections. Experimental results from the 238U on 248Cm reaction, including empirical extrapolations, are compared with theoretical model calculations predicting relatively high cross sections for neutron-rich nuclei. Experiments to test the validity of such predictions are proposed. Comparisons between rather symmetric heavy-ion reactions like 238U on 248Cm (or heavier targets up to 254Es) with very asymmetric ones like 18O on 254Es reveal that the ones with 238U as a projectile have the highest potential in the superheavy element region while the latter ones can be advantageous for the synthesis of heavy actinide isotopes. Concepts for highly efficient recoil separators designed for transfer products are presented.

  17. Study of the diffusion of an emulsion in the human skin by pulsed photoacoustic spectroscopy: experiment and numerical simulation

    NASA Astrophysics Data System (ADS)

    Benamar, N.; Lahjomri, F.; Chatri, E.; Leblanc, R. M.

    2004-12-01

    We previously used the Pulsed Photoacoustic Spectroscopy to quantify sunscreen chromophore diffusion into human skin, and suggested a methodology to evaluate the time and the depth diffusion profile into human skin. In the present study we present the results obtained for the diffusion of an emulsion in human skin, which is used in the sunscreen compositions. This study shows, for the first time, a particular behaviour due to a chemical reaction inside the skin during the diffusion process. This result brings a particularly interesting technique through the PPAS spectroscopy, to evaluate in situ, the eventual chemical reactions that can occur during drug diffusion into human skin. Numerical simulation allows us to understand the impact of thermal, optical and geometrical parameters on the photoacoustic signal and thus the physics of the diffusion phenomenon. The present simulation shows clearly that the tmax values corresponding to the maximum of the photoacoustic signal magnitude, Δ P max, decrease when the thickness, ell , of the sample decrease. Conclusions about possibilities and limitations of the considered model are discussed.

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

    NASA Technical Reports Server (NTRS)

    Avedisian, C. Thomas

    1997-01-01

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

  19. Latest Developments in Nuclear Emulsion Technology

    NASA Astrophysics Data System (ADS)

    Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. These trajectories are recorded as tracks consist of a lot of silver grains. The size of silver grain is about 1 μm, so that nuclear emulsion has submicron three-dimensional spatial resolution, which gives us a few mrad three-dimensional angular resolution. The important technical progress was speed-up of the read-out technique of nuclear emulsions built with optical microscope system. We succeeded in developing a high-speed three-dimensional read-out system named Super Ultra Track Selector (S-UTS) with the operating read-out speed of approximately 50 cm2/h. Nowadays we are developing the nuclear emulsion gel independently in Nagoya University by introducing emulsion gel production machine. Moreover, we are developing nuclear emulsion production technologies (gel production, poring and mass production). In this paper, development of nuclear emulsion technologies for the OPERA experiment, applications by the technologies and current development are described.

  20. Oil emulsions of fluorosilicone fluids

    SciTech Connect

    Keil, J. W.

    1985-08-27

    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.

  1. Multidimensional analysis of data obtained in experiments with X-ray emulsion chambers and extensive air showers

    NASA Technical Reports Server (NTRS)

    Chilingaryan, A. A.; Galfayan, S. K.; Zazyan, M. Z.; Dunaevsky, A. M.

    1985-01-01

    Nonparametric statistical methods are used to carry out the quantitative comparison of the model and the experimental data. The same methods enable one to select the events initiated by the heavy nuclei and to calculate the portion of the corresponding events. For this purpose it is necessary to have the data on artificial events describing the experiment sufficiently well established. At present, the model with the small scaling violation in the fragmentation region is the closest to the experiments. Therefore, the treatment of gamma families obtained in the Pamir' experiment is being carried out at present with the application of these models.

  2. WIMP tracking with cryogenic nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Kimura, M.; Naka, T.; Furuya, S.; Asada, T.; Katsuragawa, T.; Yoshimoto, M.; Umemoto, A.; Machii, S.; Ichiki, H.; Sato, O.; Hoshino, Y.

    2017-02-01

    Directional dark matter search experiments enable us to reveal the presence of Weakly Interacting Massive Particles. A promising detector for a directional measurement is a fine-grained nuclear emulsion consisting of fine crystals of silver bromide with 20 nm or 40 nm size. A critical task for the success of the experiment is to remove background tracks of electrons coming from stopping beta rays of 14C decays in the nuclear emulsion. An electron rejection power of at least 10-10 is needed in order to start a 10 kg experiment. We present a novel cryogenic approach to reject the electron background that makes use of the phonon effect in nuclear emulsion. For the proof of principle, we have been investigating the sensitivity of fine-grained nuclear emulsions as a function of temperature by exposing to gamma rays and ion beams with an ion implant system in the range of 77-300 K. Results of gamma ray exposure indicate that the electron rejection power is estimated to be better than 3 ×10-9 at 77 K. Results of ion exposure imply that fine-grained nuclear emulsion is sensitive to ions which are light and heavy and ion tracks' angle can be measured.

  3. Detonation Characteristics of Mixtures of HMX and Emulsion Explosives

    DTIC Science & Technology

    1989-04-01

    approximately 20 percent HM to an emulsion explosive results in a substantial increase in initiation sensitivity . This observation is based on the premise of an...inverse relationship between failure diameter and initiation sensitivity for the HYX’ emulsion explosive system. I ii UNCLASSIFIED IIUWAOTV...for height-of-burst experiments. The issues of safety, thermal stability, initiation sensitivity , detonation performance, mechanical properties

  4. SAFETY AND UTILITY OF I.V. FAT EMULSION FOR HUMAN INTRAVENOUS ADMINISTRATION.

    DTIC Science & Technology

    The initial clinical experiences of our group with a European fat emulsion called Intralipid is reported. This emulsion is composed of soy bean oil...failed to show correlation between febrile response and rapidity with which clearing of the emulsion occurred. It is concluded that Intralipid is not a safe or suitable product for routine clinical use. (Author)

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

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2013-08-01

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

  6. Emulsions for interfacial filtration.

    SciTech Connect

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

    2006-11-01

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

  7. Linear oil displacement by the emulsion entrapment process. [Dissertation

    SciTech Connect

    Schmidt, D.P.

    1982-01-01

    Lack of mobility control is one of the major impediments to successful enhanced oil recovery, especially for high viscosity oils. This work presents experimental and theoretical results for linear secondary oil displacements using dilute, stable suspensions of oil drops. The major hypothesis is that emulsions provide mobility control through entrapment or local permeability reduction, not through viscosity ratio improvement. In order to describe the displacement process, previous emulsion filtration theory is extended to longer cores and to two-phase flow. Quantitative agreement between theory and experiment is satisfactory for continuous secondary oil displacement with various drop-size emulsions in unconsolidated sand packs of permeabilities ranging from 0.7 ..mu..m/sup 2/ to 3.3 ..mu..m/sup 2/. Linear emulsion floods are shown to be most effective when the mean drop-size to pore-size ratio is in the region between straining and interception at the emulsion shock. Floods are more effective when the emulsion concentration is high which minimizes retention lag. Additionally, a parallel flooding apparatus is utilized to determine qualitatively the macroscopic benefits of emulsion mobility control. Direct analogies are established between augmented oil recovery with dilute emulsions and with entrapping polymers.

  8. Increased bioavailability of a transdermal application of a nano-sized emulsion preparation.

    PubMed

    Kotyla, T; Kuo, F; Moolchandani, V; Wilson, T; Nicolosi, R

    2008-01-22

    The aim of this study was to compare the transdermal application of a nano-sized emulsion versus a micron-sized emulsion preparation of delta tocopherol as it relates to particle size and bioavailability. Two separate experiments were performed using seven F1B Syrian Golden hamsters, 1 week apart. Each emulsion preparation consisted of canola oil, polysorbate 80, deionized water and delta tocopherol; the only difference between the two preparations was processing the nano-sized emulsion with the Microfluidizer Processor. Both were formulated into a cream and applied to the shaven dorsal area. The particle size of the micron-sized emulsion preparation was 2788 nm compared to 65 nm for the nano-sized emulsion formulation. Two hours post-application, hamsters that were applied the nano-sized emulsion had a 36-fold significant increase of plasma delta tocopherol, where as hamsters that were applied the micron-sized emulsion only had a 9-fold significant increase, compared to baseline, respectively. At 3h post-application, plasma delta tocopherol had significantly increased 68-fold for hamsters applied the nano-sized emulsion, whereas only an 11-fold significant increase was observed in hamsters applied the micron-sized emulsion, compared to baseline, respectively. Significant differences were also observed between the nano-sized and micron-sized emulsion at 2 and 3h post-application. This study suggests that nano-sized emulsions significantly increase the bioavailability of transdermally applied delta tocopherol.

  9. Effects of silicone emulsifiers on in vitro skin permeation of sunscreens from cosmetic emulsions.

    PubMed

    Montenegro, Lucia; Paolino, Donatella; Puglisi, Giovanni

    2004-01-01

    The effects of different silicone emulsifiers on the in vitro permeation through human skin of two sunscreens (octylmethoxycinnamate, OMC, and butylmethoxydibenzoylmethane, BMBM) were investigated from cosmetic emulsions. The formulations being tested were prepared using the same oil and aqueous phase ingredients and the following silicone emulsifiers: dimethicone copolyol and cyclomethicone (emulsion 1), cetyldimethicone copolyol (emulsion 2), polyglyceryl-4-isostearate and cetyldimethicone copolyol and hexyllaurate (emulsion 3), lauryldimethicone copolyol (emulsion 4), and cyclomethicone and dimethicone copolyol (emulsion 5). The cumulative amount of OMC that permeated in vitro through human skin after 22 h from emulsions 1-5 decreased in the order 2 approximate, equals 1 > 5 > 4 approximate, equals 3 and was about twofold higher from emulsion 2 compared to emulsion 4. As for BMBM, no significant difference was observed in regard to its skin permeation from the emulsions being tested. In vitro release experiments of OMC and BMBM from emulsions 1-5 were performed through cellulose acetate membranes using Franz diffusion cells. Emulsions 1-3 showed an initial slow release of BMBM followed by a fast release phase, while the release of OMC showed a different pattern since the sunscreen was released very rapidly at the beginning of the experiment and then a plateau was observed followed by a second step of fast release. A pseudo-first-order release rate was observed only for BMBM from emulsion 4, while emulsion 5 released very small amounts of both sunscreens during 22 h. These findings could be attributed both to changes in sunscreen thermodynamic activity in the vehicle and to modified interactions between the active ingredient and the formulation components. The results of this study suggest that the type of silicone emulsifier used to prepare sunscreen emulsions should be carefully chosen in order to prevent the percutaneous absorption of sunscreens from these

  10. Transport and Retention of Emulsion Droplets in Sandy Porous Media

    NASA Astrophysics Data System (ADS)

    Esahani, S. G.; Muller, K.; Chapra, S. C.; Ramsburg, A.

    2014-12-01

    Emulsions are commonly used as amendments during remediation; yet, the processes controlling the distribution of droplets within the subsurface are not well understood. Given that inadequate spatial and/or temporal delivery of amendments often leads to ineffective treatment, there is a need to better understand emulsion transport. Experiments were conducted to evaluate the transport and retention of emulsion droplets in columns containing Ottawa sands. Breakthrough curves and deposition profiles from these experiments were interrogated using a mathematical model capable of describing attachment, detachment, and straining to begin to elucidate the physical processes controlling delivery. Emulsions were constructed by stabilizing soybean oil droplets within a continuous aqueous phase. Physical properties of the resulting oil-in-water emulsions were favorable for subsurface delivery (nominal properties: 1 g/mL density; 10 cP viscosity; and 1.5 μm droplet d50). Emulsions were introduced to the columns for approximately two pore volumes and followed by an extended flush of background solution. Effluent droplet size distributions did not vary significantly over the course of the experiment and remained similar to those measured for the influent emulsion. Emulsion breakthrough curves exhibited tailing, and deposition profiles were found to be hyper-exponential and unaffected by extended periods of background flow. Depending on emulsion composition and flow characteristics, 10-30% of the injected emulsion was retained on the sand suggesting a non-negligible influence on accessible porosity over the course of the experiment. Experimental results were further interpreted using a droplet transport model that accounts for temporal and spatial variation in porosity due to the retention of the emulsion droplets. At present the model assumes a uniform size distribution of inelastic emulsion droplets which are transported by advection and dispersion, and exchanged with the solid

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

    PubMed

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

    2014-11-04

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

  12. Picosecond Cherenkov detectors for high-energy heavy ion experiments at LHEP/JINR

    NASA Astrophysics Data System (ADS)

    Yurevich, V. I.; Batenkov, O. I.

    2016-07-01

    The modular Cherenkov detectors based on MCP-PMTs are developed for study Au+Au collisions in MPD and BM@N experiments with beams of Nuclotron and future collider NICA in Dubna. The aim of the detector is fast and effective triggering nucleus-nucleus collisions and generation of start signal for TOF detectors. The detector performance is studied with MC simulation and test measurements with a beam of Nuclotron.

  13. Holographic DESA emulsions

    NASA Astrophysics Data System (ADS)

    Duenkel, Lothar; Eichler, Juergen; Schneeweiss, Claudia; Ackermann, Gerhard

    2005-04-01

    The DESA material is an ultra-fine grained silver bromide emulsion referring to the name of its four inventors (D)uenkel, (E)ichler, (S)chneeweiss, (A)ckermann of the University of Applied Sciences in Berlin, Germany. The thickness of the dried layer is between 5 and 7.5 μm, and the mean grain size is by about 15 nm, as determined by TEM. During manufacturing, emulsion precipitation and coating are separated strictly from spectral and chemical sensitization. Thus, a high performance could be obtained. Resolution is estimated higher than 8000 lp/mm. Sensitivity amounts to 80 up to 120 μJoules/cm2 for maximum diffraction efficiency by recording Denisyuk white-light reflection holograms at 632,8 nm (HeNe laser). The paper provides an insight into fundamentals of the ultra-fine grained silver halide technology together with new challenges for further developments under theoretical and practical aspects.

  14. FINE GRAIN NUCLEAR EMULSION

    DOEpatents

    Oliver, A.J.

    1962-04-24

    A method of preparing nuclear track emulsions having mean grain sizes less than 0.1 microns is described. The method comprises adding silver nitrate to potassium bromide at a rate at which there is always a constant, critical excess of silver ions. For minimum size grains, the silver ion concentration is maintained at the critical level of about pAg 2.0 to 5.0 during prectpitation, pAg being defined as the negative logarithm of the silver ion concentration. It is preferred to eliminate the excess silver at the conclusion of the precipitation steps. The emulsion is processed by methods in all other respects generally similar to the methods of the prior art. (AEC)

  15. Showing Emulsion Properties with Common Dairy Foods

    NASA Astrophysics Data System (ADS)

    Bravo-Diaz, Carlos; Gonzalez-Romero, Elisa

    1996-09-01

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

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

    SciTech Connect

    Zayarnaya, I. S.

    2008-02-15

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

  17. Cyclodextrin stabilised emulsions and cyclodextrinosomes.

    PubMed

    Mathapa, Baghali G; Paunov, Vesselin N

    2013-11-07

    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 β-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.

  18. Improving the detection efficiency in nuclear emulsion trackers

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Bozza, C.; Buonaura, A.; Consiglio, L.; D`Ambrosio, N.; Lellis, G. De; De Serio, M.; Di Capua, F.; Di Crescenzo, A.; Di Ferdinando, D.; Di Marco, N.; Fini, R. A.; Galati, G.; Giacomelli, G.; Grella, G.; Hosseini, B.; Kose, U.; Lauria, A.; Longhin, A.; Mandrioli, G.; Mauri, N.; Medinaceli, E.; Montesi, M. C.; Paoloni, A.; Pastore, A.; Patrizii, L.; Pozzato, M.; Pupilli, F.; Rescigno, R.; Roda, M.; Rosa, G.; Schembri, A.; Shchedrina, T.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Spinetti, M.; Stellacci, S. M.; Tenti, M.; Tioukov, V.

    2015-03-01

    Nuclear emulsion films are a tracking device with unique space resolution. Their use in nowadays large-scale experiments relies on the availability of automated microscope operating at very high speed. In this paper we describe the features and the latest improvements of the European Scanning System, a last-generation automated microscope for emulsion scanning. In particular, we present a new method for the recovery of tracking inefficiencies. Stacks of double coated emulsion films have been exposed to a 10 GeV/c pion beam. Efficiencies as high as 98% have been achieved for minimum ionising particle tracks perpendicular to the emulsion films and of 93% for tracks with tan(θ) ≃ 0.8.

  19. Rubberized asphalt emulsion

    SciTech Connect

    Wilkes, E.

    1986-09-02

    A method is described of making a rubberized asphalt composition which comprises the steps of: (a) combining asphalt with a hydrocarbon oil having a flash point of 300/sup 0/F. or more to provide a homogenous asphalt-oil mixture or solution, (b) then combining the asphalt-oil mixture with a particulate rubber at a temperature sufficient to provide a homogenous asphalt-rubber-oil gel, and (c) emulsifying the asphalt-rubber-oil gel by passing the gel, water, and an emulsifying agent through a colloid mill to provide an emulsion.

  20. Sub-micron alignment for nuclear emulsion plates using low energy electrons caused by radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Miyamoto, S.; Ariga, A.; Fukuda, T.; Kazuyama, M.; Komatsu, M.; Nakano, T.; Niwa, K.; Sato, O.; Takahashi, S.

    2007-06-01

    Nuclear emulsion plates are employed in three-dimensional charged particle detectors that have sub-micron position resolution over 1 m2 with no dead space and no dead time. These detectors are suitable for the study of short-lived particle decays, and direct detection of neutrino interactions of all flavors. Typically emulsion plates are used in a stacked structure. Precise alignment between plates is required for physics analysis. The most accurate alignment method is to use tracks passing through the emulsion plates. The accuracy is about 0.2 μm. However, in an experiment with low track density alignment accuracy decreases to 20 μm because of plate distortion and it becomes more difficult to perform the analysis. This paper describes a new alignment method between emulsion plates by using trajectories of low energy electrons originating from environmental radioactive isotopes. As a trial emulsion plates were exposed to β-rays and γ-rays from K40. The trajectories which passed through emulsion layers were detected by a fully automated emulsion readout system. Using this method, the alignment between emulsion plates is demonstrated to be sub-micron. This method can be applied to many nuclear emulsion experiments. For example, the location of neutrino interaction vertices in the OPERA experiment can benefit from this new technique.

  1. A quality by design approach to optimization of emulsions for electrospinning using factorial and D-optimal designs.

    PubMed

    Badawi, Mariam A; El-Khordagui, Labiba K

    2014-07-16

    Emulsion electrospinning is a multifactorial process used to generate nanofibers loaded with hydrophilic drugs or macromolecules for diverse biomedical applications. Emulsion electrospinnability is greatly impacted by the emulsion pharmaceutical attributes. The aim of this study was to apply a quality by design (QbD) approach based on design of experiments as a risk-based proactive approach to achieve predictable critical quality attributes (CQAs) in w/o emulsions for electrospinning. Polycaprolactone (PCL)-thickened w/o emulsions containing doxycycline HCl were formulated using a Span 60/sodium lauryl sulfate (SLS) emulsifier blend. The identified emulsion CQAs (stability, viscosity and conductivity) were linked with electrospinnability using a 3(3) factorial design to optimize emulsion composition for phase stability and a D-optimal design to optimize stable emulsions for viscosity and conductivity after shifting the design space. The three independent variables, emulsifier blend composition, organic:aqueous phase ratio and polymer concentration, had a significant effect (p<0.05) on emulsion CQAs, the emulsifier blend composition exerting prominent main and interaction effects. Scanning electron microscopy (SEM) of emulsion-electrospun NFs and desirability functions allowed modeling of emulsion CQAs to predict electrospinnable formulations. A QbD approach successfully built quality in electrospinnable emulsions, allowing development of hydrophilic drug-loaded nanofibers with desired morphological characteristics.

  2. Programmed emulsions for sodium reduction in emulsion based foods.

    PubMed

    Chiu, Natalie; Hewson, Louise; Fisk, Ian; Wolf, Bettina

    2015-05-01

    In this research a microstructure approach to reduce sodium levels in emulsion based foods is presented. If successful, this strategy will enable reduction of sodium without affecting consumer satisfaction with regard to salty taste. The microstructure approach comprised of entrapment of sodium in the internal aqueous phase of water-in-oil-in-water emulsions. These were designed to destabilise during oral processing when in contact with the salivary enzyme amylase in combination with the mechanical manipulation of the emulsion between the tongue and palate. Oral destabilisation was achieved through breakdown of the emulsion that was stabilised with a commercially modified octenyl succinic anhydride (OSA)-starch. Microstructure breakdown and salt release was evaluated utilising in vitro, in vivo and sensory methods. For control emulsions, stabilised with orally inert proteins, no loss of structure and no release of sodium from the internal aqueous phase was found. The OSA-starch microstructure breakdown took the initial form of oil droplet coalescence. It is hypothesised that during this coalescence process sodium from the internalised aqueous phase is partially released and is therefore available for perception. Indeed, programmed emulsions showed an enhancement in saltiness perception; a 23.7% reduction in sodium could be achieved without compromise in salty taste (p < 0.05; 120 consumers). This study shows a promising new approach for sodium reduction in liquid and semi-liquid emulsion based foods.

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

    NASA Astrophysics Data System (ADS)

    Alvarado, Vladimir; Wang, Xiuyu

    2009-11-01

    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.

  4. Preparation of Pickering Double Emulsions Using Block Copolymer Worms

    PubMed Central

    2015-01-01

    The rational formulation of Pickering double emulsions is described using a judicious combination of hydrophilic and hydrophobic block copolymer worms as highly anisotropic emulsifiers. More specifically, RAFT dispersion polymerization was utilized to prepare poly(lauryl methacrylate)–poly(benzyl methacrylate) worms at 20% w/w solids in n-dodecane and poly(glycerol monomethacrylate)–poly(2-hydroxypropyl methacrylate)–poly(benzyl methacrylate) worms at 13% w/w solids in water by polymerization-induced self-assembly (PISA). Water-in-oil-in-water (w/o/w) double emulsions can be readily prepared with mean droplet diameters ranging from 30 to 80 μm using a two-stage approach. First, a w/o precursor emulsion comprising 25 μm aqueous droplets is prepared using the hydrophobic worms, followed by encapsulation within oil droplets stabilized by the hydrophilic worms. The double emulsion droplet diameter and number of encapsulated water droplets can be readily varied by adjusting the stirring rate employed during the second stage. For each stage, the droplet volume fraction is relatively high at 0.50. The double emulsion nature of the final formulation was confirmed by optical and fluorescence microscopy studies. Such double emulsions are highly stable to coalescence, with little or no change in droplet diameter being detected over storage at 20 °C for 10 weeks as judged by laser diffraction. Preliminary experiments indicate that the complementary o/w/o emulsions can also be prepared using the same pair of worms by changing the order of homogenization, although somewhat lower droplet volume fractions were required in this case. Finally, we demonstrate that triple and even quadruple emulsions can be formulated using these new highly anisotropic Pickering emulsifiers. PMID:25834923

  5. Formation and stability of polychlorinated biphenyl Pickering emulsions.

    PubMed

    Roy-Perreault, Andréanne; Kueper, Bernard H; Rawson, Jim

    2005-03-01

    An emulsion stabilized by colloidal suspensions of finely divided solids is known as a Pickering emulsion. The potential for polychlorinated biphenyls (PCBs) to form Pickering emulsions ex situ when in contact with powdered solids, such as clays and metal oxides, is investigated here. Bentonite, iron oxide and magnesium oxide dispersions proved to be robust Pickering emulsion stabilizers, whereas manganese oxide dispersions were not. Batch experiments revealed that emulsions can be formed using a moderately low energy input and can be stabilized with solid concentrations as low as 0.5 wt.%. For the base conditions (volumetric oil fraction (phi(oil))=30 vol.%; solid concentration (chi)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 mum, depending on the solid used in the colloidal dispersion. The average droplet size varied at early time, but for most conditions stabilized to a steady-state value 1 week after preparation. The effect of Ostwald ripening was limited. At greater than 0.5 wt.% concentration, the efficiency of the solid dispersion as a stabilizer was dependant on the volumetric oil fraction but not on the solid concentration. Generally, systems with volumetric oil fractions outside of the 20-70 vol.% range were unstable. The emulsions' droplet stability, average droplet size and size distribution were observed to vary as a function of the amount of energy provided to the system, the volumetric oil fraction, and the concentration of the solid in the aqueous dispersion. It is hypothesized that drilling through fractured rock in the immediate vicinity of dense, non-aqueous phase liquid (DNAPL) PCBs may provide both the energy and solid material necessary to form Pickering emulsions.

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

    ERIC Educational Resources Information Center

    Mabrouk, Suzanne T.

    2004-01-01

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

  7. Transport and Retention of Concentrated Oil-in-Water Emulsions in Sandy Porous Media

    NASA Astrophysics Data System (ADS)

    Muller, K.; Esahani, S. G.; Steven, C. C.; Ramsburg, A.

    2015-12-01

    Oil-in-water emulsions are widely employed to promote biotic reduction of contaminants; however, emulsions can also be used to encapsulate and deliver active ingredients required for long-term subsurface treatment. Our research focuses on encapsulating alkalinity-releasing particles in oil-in-water emulsions for sustained control of subsurface pH. Typical characteristics of these emulsions include kinetically stable for >20 hr; 20% soybean oil; 1 g/mL density; 8-10 cP viscosity; and 1.5 μm droplet d50, with emulsions developed for favorable subsurface delivery. The viscosity of the oil-in-water emulsions was found to be a function of oil content. Ultimately we aim to model both emulsion delivery and alkalinity release (from retained emulsion droplets) to provide a description of pH treatment. Emulsion transport and retention was investigated via a series of 1-d column experiments using varying particle size fractions of Ottawa sand. Emulsions were introduced for approximately two pore volumes followed by a flush of background solution (approx. ρ=1 g/mL; μ=1cP). Emulsion breakthrough curves exhibit an early fall on the backside of the breakthrough curve along with tailing. Deposition profiles are found to be hyper-exponential and unaffected by extended periods of background flow. Particle transport models established for dilute suspensions are unable to describe the transport of the concentrated emulsions considered here. Thus, we explore the relative importance of additional processes driving concentrated droplet transport and retention. Focus is placed on evaluating the role of attachment-detachment-straining processes, as well as the influence of mixing from both viscous instabilities and variable water saturation due to deposited mass.

  8. In vitro skin permeation of sunscreen agents from O/W emulsions.

    PubMed

    Montenegro, L; Carbone, C; Paolino, D; Drago, R; Stancampiano, A H; Puglisi, G

    2008-02-01

    The effects of different emulsifiers on the in vitro permeation through human skin of two sunscreen agents [octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM)] were investigated from O/W emulsions. The test formulations were prepared using the same oil and aqueous phase ingredients and the following emulsifier and coemulsifier systems: Emulgade SE((R)) (ceteareth-12 and ceteareth-20 and cetearyl alcohol and cetyl palmitate) and glycerylmonostearate (emulsion 1); Brij 72((R)) (steareth-2), Brij 721((R)) (steareth-21) and cetearyl alcohol (emulsion 2); Phytocream((R)) (potassium palmitoyl-hydrolysed wheat protein and glyceryl stearate and cetearyl alcohol) and glycerylmonostearate (emulsion 3); Montanov 68((R)) (cetearyl glucoside and cetearyl alcohol) (emulsion 4); Xalifin-15((R)) (C(15-20) acid PEG-8 ester) and cetearyl alcohol (emulsion 5). The cumulative amount of OMC that permeated in vitro through human skin after 22 h from the formulations being tested decreased in the order 3 > 1 congruent with 4 > 5 > 2 and was about nine-fold higher from emulsion 3 compared with that from emulsion 2. As regards BMBM, no significant difference was observed as regards its skin permeation from emulsions 1, 3, 4 and 5, whereas formulation 2 allowed significantly lower amounts of BMBM to permeate the skin. In vitro release experiments of OMC and BMBM from emulsions 1-6 through cellulose acetate membranes showed that only emulsions 4 and 5 provided pseudo-first-order release rates only for OMC. The results of this study suggest that the type of emulsifying systems used to prepare an O/W emulsion may strongly affect sunscreen skin permeation from these formulations. Therefore, the vehicle effects should be carefully considered in the formulation of sunscreen products.

  9. Electromagnetic Scale Models Using Emulsions

    DTIC Science & Technology

    1989-04-01

    microwave range; the solutions have a nearly constant permittivity and a conductivity that is adjustable by varying the salt concentration. Mixtures of...emulsion. At this point, complete demulsification has occurred. The emulsion can then be reformed only by subjecting it to the process (homogenization...130-137, June 1986. [17] A. Stogryn, "Equations for calculating the dielectric constant of saline water," IEEE Trans. Microwave Theory and Tech

  10. Scaling properties of fractional momentum loss of high- pT hadrons in nucleus-nucleus collisions at sNN from 62.4 GeV to 2.76 TeV

    DOE PAGES

    Adare, A.; Afanasiev, S.; Aidala, C.; ...

    2016-02-22

    We present measurements of the fractional momentum loss (Sloss = delta pT / pT) of high-transverse-momentum-identified hadrons in heavy-ion collisions. Using pi0 in Au + Au and Cu + Cu collisions at √sNN = 62.4 and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb + Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of Sloss as a function of a number of variables: the number of participants, Npart, the number of quark participants, Nqp, the charged-particle density, dNch/dη, and themore » Bjorken energy density times the equilibration time, epsilonBjτ0. We also find that the pT, where Sloss has its maximum, varies both with centrality and collision energy. Above the maximum, Sloss tends to follow a power-law function with all four scaling variables. Finally, the data at √sNN = 200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of Sloss with dNch/dη and εBjτ0, lending insight into the physics of parton energy loss.« less

  11. Scaling properties of fractional momentum loss of high-pT hadrons in nucleus-nucleus collisions at √{sN N} from 62.4 GeV to 2.76 TeV

    NASA Astrophysics Data System (ADS)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Alexander, J.; Alfred, M.; Al-Ta'Ani, H.; Angerami, A.; Aoki, K.; Apadula, N.; Aphecetche, L.; Aramaki, Y.; Armendariz, R.; Aronson, S. H.; Asai, J.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Baldisseri, A.; Bandara, N. S.; Bannier, B.; Barish, K. N.; Barnes, P. D.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Batsouli, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Beaumier, M.; Beckman, S.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Blau, D. S.; Boissevain, J. G.; Bok, J. S.; Borel, H.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Castera, P.; Chang, B. S.; Charvet, J.-L.; Chen, C.-H.; Chernichenko, S.; Chi, C. Y.; Chiba, J.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Churyn, A.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cleven, C. R.; Cole, B. A.; Comets, M. P.; Connors, M.; Constantin, P.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Danley, T. W.; Das, K.; Datta, A.; Daugherity, M. S.; David, G.; Deaton, M. B.; Deblasio, K.; Dehmelt, K.; Delagrange, H.; Denisov, A.; D'Enterria, D.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Ding, L.; Dion, A.; Diss, P. B.; Do, J. H.; Donadelli, M.; D'Orazio, L.; Drapier, O.; Drees, A.; Drees, K. A.; Dubey, A. K.; Durham, J. M.; Durum, A.; Dutta, D.; Dzhordzhadze, V.; Edwards, S.; Efremenko, Y. V.; Egdemir, J.; Ellinghaus, F.; Emam, W. S.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Feege, N.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gadrat, S.; Gainey, K.; Gal, C.; Gallus, P.; Garg, P.; Garishvili, A.; Garishvili, I.; Ge, H.; Giordano, F.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Gosset, J.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gunji, T.; Guo, L.; Gustafsson, H.-Å.; Hachiya, T.; Hadj Henni, A.; Haegemann, C.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Hamilton, H. F.; Han, R.; Han, S. Y.; Hanks, J.; Harada, H.; Hartouni, E. P.; Haruna, K.; Hasegawa, S.; Haseler, T. O. S.; Hashimoto, K.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hiejima, H.; Hill, J. C.; Hobbs, R.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Hoshino, T.; Hotvedt, N.; Huang, J.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ide, J.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imrek, J.; Inaba, M.; Inoue, Y.; Iordanova, A.; Isenhower, D.; Isenhower, L.; Ishihara, M.; Isobe, T.; Issah, M.; Isupov, A.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jezghani, M.; Jia, J.; Jiang, X.; Jin, J.; Jinnouchi, O.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kanda, S.; Kaneta, M.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kanou, H.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Key, J. A.; Khachatryan, V.; Khanzadeev, A.; Kijima, K. M.; Kikuchi, J.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.; Kim, E.-J.; Kim, G. W.; Kim, H. J.; Kim, K.-B.; Kim, M.; Kim, S. H.; Kim, Y.-J.; Kim, Y. K.; Kimelman, B.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Kitamura, R.; Kiyomichi, A.; Klatsky, J.; Klay, J.; Klein-Boesing, C.; Kleinjan, D.; Kline, P.; Koblesky, T.; Kochenda, L.; Kochetkov, V.; Komatsu, Y.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kotov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Krizek, F.; Kubart, J.; Kunde, G. J.; Kurihara, N.; Kurita, K.; Kurosawa, M.; Kweon, M. J.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, B.; Lee, D. M.; Lee, J.; Lee, K.; Lee, K. B.; Lee, K. S.; Lee, M. K.; Lee, S.; Lee, S. H.; Lee, S. R.; Lee, T.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Leitner, E.; Lenzi, B.; Lewis, B.; Li, X.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Love, B.; Luechtenborg, R.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Malakhov, A.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Mašek, L.; Masui, H.; Masumoto, S.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Miller, T. E.; Milov, A.; Mioduszewski, S.; Mishra, D. K.; Mishra, M.; Mitchell, J. T.; Mitrovski, M.

    2016-02-01

    Measurements of the fractional momentum loss (Sloss≡δ pT/pT ) of high-transverse-momentum-identified hadrons in heavy-ion collisions are presented. Using π0 in Au +Au and Cu +Cu collisions at √{sNN}=62.4 and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb +Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of Sloss as a function of a number of variables: the number of participants, Npart, the number of quark participants, Nqp, the charged-particle density, d Nch/d η , and the Bjorken energy density times the equilibration time, ɛBjτ0 . We find that the pT, where Sloss has its maximum, varies both with centrality and collision energy. Above the maximum, Sloss tends to follow a power-law function with all four scaling variables. The data at √{sNN}=200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of Sloss with d Nch/d η and ɛBjτ0 , lending insight into the physics of parton energy loss.

  12. Innovative Applications Of Food Related Emulsions.

    PubMed

    S, Kiokias; T, Varzakas

    2016-02-06

    Research on oxidative stability of multiple emulsions is very scarce. Given that this is a relevant topic that must be ascertained before the successful application of multiple emulsions in foods (especially when a combination of highly unsaturated oils is used as a lipid phase), this review mainly focus on various aspects of the multiple emulsions. Fat replacement in meat products using emulsions is critically discussed along with innovative applications of natural antioxidants in food based emulsions and multiple emulsions based on bioactive compounds/encapsulation as well as confectionery products.

  13. Optimizing organoclay stabilized Pickering emulsions.

    PubMed

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

    2011-04-15

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

  14. High speed automated microtomography of nuclear emulsions and recent application

    NASA Astrophysics Data System (ADS)

    Tioukov, V.; Aleksandrov, A.; Consiglio, L.; De Lellis, G.; Vladymyrov, M.

    2015-12-01

    The development of high-speed automatic scanning systems was the key-factor for massive and successful emulsions application for big neutrino experiments like OPERA. The emulsion detector simplicity, the unprecedented sub-micron spatial resolution and the unique ability to provide intrinsically 3-dimensional spatial information make it a perfect device for short-living particles study, where the event topology should be precisely reconstructed in a 10-100 um scale vertex region. Recently the exceptional technological progress in image processing and automation together with intensive R&D done by Italian and Japanese microscopy groups permit to increase the scanning speed to unbelievable few years ago m2/day scale and so greatly extend the range of the possible applications for emulsion-based detectors to other fields like: medical imaging, directional dark matter search, nuclear physics, geological and industrial applications.

  15. Arrested of coalescence of emulsion droplets of arbitrary size

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

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

  16. Real time study of development process in holographic emulsions

    NASA Astrophysics Data System (ADS)

    Fimia, A.; Blaya, S.; Carretero, L.; Madrigal, R. F.; Mallavia, R.

    2000-01-01

    In this paper we present the theoretical and experimental study using a real time technique for the measurement of the optical density when the emulsion is developing. Good agreement was observed between theory and experiment. We exposed an Agfa Gevaert 8E56HD emulsion with an Argon laser tuned at 514 nm and we measured the variation in optical density when the emulsion was put into the developer bath at 20°C. This method allows us to study the dynamics of different developers at different energy of storage. It also provides a way to optimize the composition of developers as a function of the chemical composition, temperature and other secondary factors as superadditivity and non-linear processes.

  17. High speed automated microtomography of nuclear emulsions and recent application

    SciTech Connect

    Tioukov, V.; Aleksandrov, A.; Consiglio, L.; De Lellis, G.; Vladymyrov, M.

    2015-12-31

    The development of high-speed automatic scanning systems was the key-factor for massive and successful emulsions application for big neutrino experiments like OPERA. The emulsion detector simplicity, the unprecedented sub-micron spatial resolution and the unique ability to provide intrinsically 3-dimensional spatial information make it a perfect device for short-living particles study, where the event topology should be precisely reconstructed in a 10-100 um scale vertex region. Recently the exceptional technological progress in image processing and automation together with intensive R&D done by Italian and Japanese microscopy groups permit to increase the scanning speed to unbelievable few years ago m{sup 2}/day scale and so greatly extend the range of the possible applications for emulsion-based detectors to other fields like: medical imaging, directional dark matter search, nuclear physics, geological and industrial applications.

  18. Hadrons registration in emulsion chamber with carbon block

    NASA Technical Reports Server (NTRS)

    Tomaszewski, A.; Wlodarczyk, Z.

    1985-01-01

    Nuclear-electro-magnetic cascade (NEC) in X-ray emulsion chambers with carbon block, which are usually used in the Pamir experiment, was Monte-Carlo simulated. Going over from optical density to Summary E sub gamma is discussed. The hole of NEC in the interpretation of energy spectra is analyzed.

  19. Nucleus-nucleus collisions at very high energies

    SciTech Connect

    Hansen, O.

    1990-01-01

    The present report covers the material of two lectures. The first part, contains a collection of useful formulae from relativistic kinematics and deals with invariant cross sections and multiplicities. The remainder of the paper is on strangeness production in relativistic heavy ion collisions. Some elementary rules for particle production in nucleon-nucleon interactions are presented. This paper also contains arguments on why one expects enhanced strange particle production from the quark-gluon plasma. Next is presented some selected data on strangeness production in Si + Au and other interactions at 14.6 GeV/c per nucleon and from S + S at 200 GeV/c per nucleon. Some conclusions drawn from the experimental results are presented. 10 refs.

  20. Mass dependence of critical behavior in nucleus-nucleus collisions

    SciTech Connect

    Li, T.; Bauer, W.; Craig, D.; Gualtieri, E.; Hannuschke, S.; Pak, R.; Vander Molen, A.M.; Westfall, G.D.; Winfield, J.S.; Yee, J.; Yennello, S.J.; Lacey, R.; Nadasen, A.; Tickle, R.S.; Norbeck, E.

    1994-03-01

    The {ital Z} distributions of fragments emitted from central collisions of {sup 40}Ar+{sup 45}Sc at beam energies from 15 to 115 MeV/nucleon have been fitted to power laws {sigma}({ital Z}){proportional_to}{ital Z}{sup {minus}{lambda}}. The {lambda} parameter reaches a minimum at a beam energy of 23.9{plus_minus}0.7 MeV/nucleon. A percolation model calculation reproduces the observed {ital Z} distributions for all beam energies, using the mean excitation energy as extracted from proton kinetic energy spectra. We extract the critical value of the deposited excitation energy for our system and make predictions for the dependence of this quantity on the size of the fragmenting system.

  1. Dynamics of Polydisperse Coarsening Emulsion

    NASA Astrophysics Data System (ADS)

    Mirenda, Nic; Hicock, Harry; Feitosa, Klebert; Crocker, John

    2014-03-01

    Soft glassy materials display complex fluid behavior characterized by a yield stress and distinctive elastic and viscous moduli. The complexity emerges from the disordered structure and interactions between the athermal particles. Here we study the dynamics of an optically clear and neutrally buoyantly emulsion whose droplets coarsen driven by Laplace pressure induced diffusion. The emulsion displays an anomalous loss modulus typical of coarsening foam systems. We use confocal microscopy to image the droplets, measure their size and centroid location, and track their evolution in time. The relaxation process of the coarsening emulsion is found to be marked by a continuous, slow structural evolution interspersed by sudden droplet swaps. We characterize the time scales of each process and the statistics of droplet rearrangements. We acknowledge support from Research Corporation and NSF-DMR-1229383.

  2. Can Pickering emulsion formation aid the removal of creosote DNAPL from porous media?

    PubMed

    Torres, Luis; Iturbe, Rosario; Snowden, M J; Chowdhry, Babur; Leharne, Stephen

    2008-03-01

    The purpose of this investigation was to examine the proposition that creosote, emplaced in an initially water saturated porous system, can be removed from the system through Pickering emulsion formation. Pickering emulsions are dispersions of two immiscible fluids in which coalescence of the dispersed phase droplets is hindered by the presence of colloidal particles adsorbed at the interface between the two immiscible fluid phases. Particle trapping is strongly favoured when the wetting properties of the particles are intermediate between strong water wetting and strong oil wetting. In this investigation the necessary chemical conditions for the formation of physically stable creosote-in-water emulsions protected against coalescence by bentonite particles were examined. It was established that physically stable emulsions could be formed through the judicious addition of small amounts of sodium chloride and the surfactant cetyl-trimethylammonium bromide. The stability of the emulsions was initially established by visual inspection. However, experimental determinations of emulsion stability were also undertaken by use of oscillatory rheology. Measurements of the elastic and viscous responses to shear indicated that physically stable emulsions were obtained when the viscoelastic systems showed a predominantly elastic response to shearing. Once the conditions were established for the formation of physically stable emulsions a "proof-of-concept" chromatographic experiment was carried out which showed that creosote could be successfully removed from a saturated model porous system.

  3. Controlling molecular transport in minimal emulsions

    PubMed Central

    Gruner, Philipp; Riechers, Birte; Semin, Benoît; Lim, Jiseok; Johnston, Abigail; Short, Kathleen; Baret, Jean-Christophe

    2016-01-01

    Emulsions are metastable dispersions in which molecular transport is a major mechanism driving the system towards its state of minimal energy. Determining the underlying mechanisms of molecular transport between droplets is challenging due to the complexity of a typical emulsion system. Here we introduce the concept of ‘minimal emulsions', which are controlled emulsions produced using microfluidic tools, simplifying an emulsion down to its minimal set of relevant parameters. We use these minimal emulsions to unravel the fundamentals of transport of small organic molecules in water-in-fluorinated-oil emulsions, a system of great interest for biotechnological applications. Our results are of practical relevance to guarantee a sustainable compartmentalization of compounds in droplet microreactors and to design new strategies for the dynamic control of droplet compositions. PMID:26797564

  4. Controlling molecular transport in minimal emulsions

    NASA Astrophysics Data System (ADS)

    Gruner, Philipp; Riechers, Birte; Semin, Benoît; Lim, Jiseok; Johnston, Abigail; Short, Kathleen; Baret, Jean-Christophe

    2016-01-01

    Emulsions are metastable dispersions in which molecular transport is a major mechanism driving the system towards its state of minimal energy. Determining the underlying mechanisms of molecular transport between droplets is challenging due to the complexity of a typical emulsion system. Here we introduce the concept of `minimal emulsions', which are controlled emulsions produced using microfluidic tools, simplifying an emulsion down to its minimal set of relevant parameters. We use these minimal emulsions to unravel the fundamentals of transport of small organic molecules in water-in-fluorinated-oil emulsions, a system of great interest for biotechnological applications. Our results are of practical relevance to guarantee a sustainable compartmentalization of compounds in droplet microreactors and to design new strategies for the dynamic control of droplet compositions.

  5. Detecting plastic events in emulsions simulations

    NASA Astrophysics Data System (ADS)

    Lulli, Matteo; Matteo Lulli, Massimo Bernaschi, Mauro Sbragaglia Team

    2016-11-01

    Emulsions are complex systems which are formed by a number of non-coalescing droplets dispersed in a solvent leading to non-trivial effects in the overall flowing dynamics. Such systems possess a yield stress below which an elastic response to an external forcing occurs, while above the yield stress the system flows as a non-Newtonian fluid, i.e. the stress is not proportional to the shear. In the solid-like regime the network of the droplets interfaces stores the energy coming from the work exerted by an external forcing, which can be used to move the droplets in a non-reversible way, i.e. causing plastic events. The Kinetic-Elasto-Plastic (KEP) theory is an effective theory describing some features of the flowing regime relating the rate of plastic events to a scalar field called fluidity f =γ˙/σ , i.e. the inverse of an effective viscosity. Boundary conditions have a non-trivial role not captured by the KEP description. In this contribution we will compare numerical results against experiments concerning the Poiseuille flow of emulsions in microchannels with complex boundary geometries. Using an efficient computational tool we can show non-trivial results on plastic events for different realizations of the rough boundaries. The research leading to these results has received funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/2007- 2013)/ERC Grant Agreement no. [279004].

  6. Random close packing of polydisperse jammed emulsions

    NASA Astrophysics Data System (ADS)

    Brujic, Jasna

    2010-03-01

    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.

  7. NEWS: Nuclear Emulsions for WIMP Search

    NASA Astrophysics Data System (ADS)

    Di Marco, Natalia; NEWS Collaboration

    2016-05-01

    In the field of direct Dark Matter search a different and promising approach is the directionality: the observation of the incoming apparent direction of WIMPs would in fact provide a new and unambiguous signature. The NEWS project is a very innovative approach for a high sensitivity experiment aiming at the directional detection of WIMPs: the detector is based on a novel emulsion technology called NIT (Nano Imaging Trackers) acting both as target and tracking device. In this paper we illustrate the features of a NIT-based detector and the newly developed read-out systems allowing to reach a spatial resolution of the order of 10 nm. We present the background studies and the experimental design. Finally we report about the time schedule of the experiment and the expected sensitivity for DM searches.

  8. Emulsion chamber observations and interpretation (HE 3)

    NASA Technical Reports Server (NTRS)

    Shibata, M.

    1986-01-01

    Experimental results from Emulsion Chamber (EC) experiments at mountain altitudes or at higher levels using flying carriers are examined. The physical interest in this field is concentrated on the strong interaction at the very high energy region exceeding the accelerator energy, also on the primary cosmic ray intensity and its chemical composition. Those experiments which observed cosmic ray secondaries gave information on high energy interaction characteristics through the analyses of secondary spectra, gamma-hadron families and C-jets (direct observation of the particle production occuring at the carbon target). Problems of scaling violation in fragmentation region, interaction cross section, transverse momentum of produced secondaries, and some peculiar features of exotic events are discussed.

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

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  10. Analysis of emulsion stability in acrylic dispersions

    NASA Astrophysics Data System (ADS)

    Ahuja, Suresh

    2012-02-01

    Emulsions either micro or nano permit transport or solubilization of hydrophobic substances within a water-based phase. Different methods have been introduced at laboratory and industrial scales: mechanical stirring, high-pressure homogenization, or ultrasonics. In digital imaging, toners may be formed by aggregating a colorant with a latex polymer formed by batch or semi-continuous emulsion polymerization. Latex emulsions are prepared by making a monomer emulsion with monomer like Beta-carboxy ethyl acrylate (β-CEA) and stirring at high speed with an anionic surfactant like branched sodium dodecyl benzene sulfonates , aqueous solution until an emulsion is formed. Initiator for emulsion polymerization is 2-2'- azobis isobutyramide dehydrate with chain transfer agent are used to make the latex. If the latex emulsion is unstable, the resulting latexes produce a toner with larger particle size, broader particle size distribution with relatively higher latex sedimentation, and broader molecular weight distribution. Oswald ripening and coalescence cause droplet size to increase and can result in destabilization of emulsions. Shear thinning and elasticity of emulsions are applied to determine emulsion stability.

  11. Removal of pesticides from aqueous solutions using liquid membrane emulsions

    SciTech Connect

    Norwood, V.M. III.

    1991-01-01

    Extractive liquid membrane technology is based on a water-in-oil emulsion as the vehicle to effect separation. An aqueous internal reagent phase is emulsified into an organic phase containing a surfactant and optional complexing agents. The emulsion, presenting a large membrane surface area, is then dispersed in an aqueous continuous phase containing the species to be removed. The desired species is transferred from the continuous, phase through the organic liquid membrane and concentrated in the internal reagent phase. Extraction and stripping occur simultaneously rather than sequentially as in conventional solvent extraction. Experiments were conducted to assess the feasibility of using liquid membranes to extract pesticides from rinsewaters typical of those generated by fertilizer/agrichemical dealers. A liquid membrane emulsion containing 10% NaOH as the internal reagent phase was used to extract herbicides from aqueous solution at a continuous phase:emulsion ratio of 5:1. Removals of 2,4-D, MCPA, Carbaryl, Diazinon, and Atrazine were investigated.

  12. Removal of pesticides from aqueous solutions using liquid membrane emulsions

    SciTech Connect

    Norwood, V.M. III

    1991-12-31

    Extractive liquid membrane technology is based on a water-in-oil emulsion as the vehicle to effect separation. An aqueous internal reagent phase is emulsified into an organic phase containing a surfactant and optional complexing agents. The emulsion, presenting a large membrane surface area, is then dispersed in an aqueous continuous phase containing the species to be removed. The desired species is transferred from the continuous, phase through the organic liquid membrane and concentrated in the internal reagent phase. Extraction and stripping occur simultaneously rather than sequentially as in conventional solvent extraction. Experiments were conducted to assess the feasibility of using liquid membranes to extract pesticides from rinsewaters typical of those generated by fertilizer/agrichemical dealers. A liquid membrane emulsion containing 10% NaOH as the internal reagent phase was used to extract herbicides from aqueous solution at a continuous phase:emulsion ratio of 5:1. Removals of 2,4-D, MCPA, Carbaryl, Diazinon, and Atrazine were investigated.

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

    PubMed

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

    2014-11-15

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

  14. Intravenous Lipid Emulsions in Parenteral Nutrition123

    PubMed Central

    Fell, Gillian L; Nandivada, Prathima; Gura, Kathleen M; Puder, Mark

    2015-01-01

    Fat is an important macronutrient in the human diet. For patients with intestinal failure who are unable to absorb nutrients via the enteral route, intravenous lipid emulsions play a critical role in providing an energy-dense source of calories and supplying the essential fatty acids that cannot be endogenously synthesized. Over the last 50 y, lipid emulsions have been an important component of parenteral nutrition (PN), and over the last 10–15 y many new lipid emulsions have been manufactured with the goal of improving safety and efficacy profiles and achieving physiologically optimal formulations. The purpose of this review is to provide a background on the components of lipid emulsions, their role in PN, and to discuss the lipid emulsions available for intravenous use. Finally, the role of parenteral fat emulsions in the pathogenesis and management of PN-associated liver disease in PN-dependent pediatric patients is reviewed. PMID:26374182

  15. Transport of Oil-in-Water Emulsions Designed to Deliver Reactive Iron Particles in Porous Media

    NASA Astrophysics Data System (ADS)

    Crocker, J. J.; Berge, N. D.; Ramsburg, C. A.

    2007-05-01

    Treatment of subsurface regions contaminated with DNAPL is a significant challenge to environmental restoration. The focus of remediation has recently shifted from technologies that recover the contamination to technologies that destroy the contamination in situ. One method of in situ contaminant destruction employs nano- or submicron-size particles of reactive iron metal. Application of iron-based destruction technologies is currently limited by poor delivery of the reactive particles (i.e., lack of contact between the iron particles and the DNAPL). Encapsulation of the reactive particles within an oil-in-water emulsion is a novel approach that may facilitate delivery. The goal of this project was to investigate the transport behavior of emulsions (Tallow oil, Tween 80, and Span 80) within porous media. One-dimensional column experiments were conducted to evaluate pore-clogging when emulsions containing encapsulated reactive particles were passed through two homogeneous sands with an order of magnitude difference in intrinsic permeability. In these experiments, passing an emulsion through the sand column (4.8 cm i.d.) at a constant flow rate (0.86 mL/min) increased the hydraulic gradient by a factor of approximately three. The hydraulic gradient in each experiment was observed to stabilize after one pore volume of emulsion. Subsequent flushing with water recovered the initial hydraulic gradient. Together, these observations indicate that conductivity reductions during emulsion flushing were the result of viscosity and not the result of extensive pore-clogging. Analysis of effluent samples confirmed that there was minimal retention of the emulsion within the sand column. Results from these experiments suggest that emulsion encapsulation may be an effective means for transporting reactive iron particles within the subsurface environment.

  16. Pickering emulsions for skin decontamination.

    PubMed

    Salerno, Alicia; Bolzinger, Marie-Alexandrine; Rolland, Pauline; Chevalier, Yves; Josse, Denis; Briançon, Stéphanie

    2016-08-01

    This study aimed at developing innovative systems for skin decontamination. Pickering emulsions, i.e. solid-stabilized emulsions, containing silica (S-PE) or Fuller's earth (FE-PE) were formulated. Their efficiency for skin decontamination was evaluated, in vitro, 45min after an exposure to VX, one of the most highly toxic chemical warfare agents. Pickering emulsions were compared to FE (FE-W) and silica (S-W) aqueous suspensions. PE containing an oil with a similar hydrophobicity to VX should promote its extraction. All the formulations reduced significantly the amount of VX quantified on and into the skin compared to the control. Wiping the skin surface with a pad already allowed removing more than half of VX. FE-W was the less efficient (85% of VX removed). The other formulations (FE-PE, S-PE and S-W) resulted in more than 90% of the quantity of VX removed. The charge of particles was the most influential factor. The low pH of formulations containing silica favored electrostatic interactions of VX with particles explaining the better elimination from the skin surface. Formulations containing FE had basic pH, and weak interactions with VX did not improve the skin decontamination. However, these low interactions between VX and FE promote the transfer of VX into the oil droplets in the FE-PE.

  17. Impact of acoustic cavitation on food emulsions.

    PubMed

    Krasulya, Olga; Bogush, Vladimir; Trishina, Victoria; Potoroko, Irina; Khmelev, Sergey; Sivashanmugam, Palani; Anandan, Sambandam

    2016-05-01

    The work explores the experimental and theoretical aspects of emulsification capability of ultrasound to deliver stable emulsions of sunflower oil in water and meat sausages. In order to determine optimal parameters for direct ultrasonic emulsification of food emulsions, a model was developed based on the stability of emulsion droplets in acoustic cavitation field. The study is further extended to investigate the ultrasound induced changes to the inherent properties of raw materials under the experimental conditions of sono-emulsification.

  18. Recent Studies of Pickering Emulsions: Particles Make the Difference.

    PubMed

    Wu, Jie; Ma, Guang-Hui

    2016-09-01

    In recent years, emulsions stabilized by micro- or nanoparticles (known as Pickering emulsions) have attracted much attention. Micro- or nanoparticles, as the main components of the emulsion, play a key role in the preparation and application of Pickering emulsions. The existence of particles at the interface between the oil and aqueous phases affects not only the preparation, but also the properties of Pickering emulsions, affording superior stability, low toxicity, and stimuli-responsiveness compared to classical emulsions stabilized by surfactants. These advantages of Pickering emulsions make them attractive, especially in biomedicine. In this review, the effects of the characteristics of micro- and nanoparticles on the preparation and properties of Pickering emulsions are introduced. In particular, the preparation methods of Pickering emulsions, especially uniform-sized emulsions, are listed. Uniform Pickering emulsions are convenient for both mechanistic research and applications. Furthermore, some biomedical applications of Pickering emulsions are discussed and the problems hindering their clinical application are identified.

  19. Oil-in-water emulsions for encapsulated delivery of reactive iron particles.

    PubMed

    Berge, Nicole D; Ramsburg, C Andrew

    2009-07-01

    Treatment of dense nonaqueous phase liquid (DNAPL) source zones using suspensions of reactive iron particles relies upon effective transport of the nano- to submicrometer scale iron particles within the subsurface. Recognition that poor subsurface transport of iron particles results from particle-particle and particle-soil interactions permits development of strategies which increase transport. In this work, experiments were conducted to assess a novel approach for encapsulated delivery of iron particles within porous media using oil-in-water emulsions. Objectives of this study included feasibility demonstration of producing kinetically stable, iron-containing, oil-in-water emulsions and evaluating the transport of these iron-containing, oil-in-water emulsions within water-saturated porous media. Emulsions developed in this study have mean droplet diameters between 1 and 2 microm, remain kinetically stable for > 1.5 h, and possess densities (0.996-1.00 g/mL at 22 degrees C) and dynamic viscosities (2.4-9.3 mPa x s at 22 degrees C and 20 s(-1)) that are favorable to transport within DNAPL source zones. Breakthrough curves and post-experiment extractions from column experiments conducted with medium and fine sands suggest little emulsion retention (< 0.20% wt) at a Darcy velocity of 0.4 m/day. These findings demonstrate that emulsion encapsulation is a promising method for delivery of iron particles and warrants further investigation.

  20. A new fast scanning system for the measurement of large angle tracks in nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Di Marco, N.; Galati, G.; Lauria, A.; Montesi, M. C.; Pupilli, F.; Shchedrina, T.; Tioukov, V.; Vladymyrov, M.

    2015-11-01

    Nuclear emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ lesssim 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, nuclear emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use nuclear emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.

  1. Suppression of Ostwald ripening in active emulsions

    NASA Astrophysics Data System (ADS)

    Zwicker, David; Hyman, Anthony A.; Jülicher, Frank

    2015-07-01

    Emulsions consisting of droplets immersed in a fluid are typically unstable since they coarsen over time. One important coarsening process is Ostwald ripening, which is driven by the surface tension of the droplets. Stability of emulsions is relevant not only in complex fluids but also in biological cells, which contain liquidlike compartments, e.g., germ granules, Cajal bodies, and centrosomes. Such cellular systems are driven away from equilibrium, e.g., by chemical reactions, and thus can be called active emulsions. In this paper, we study such active emulsions by developing a coarse-grained description of the droplet dynamics, which we analyze for two different chemical reaction schemes. We first consider the simple case of first-order reactions, which leads to stable, monodisperse emulsions in which Ostwald ripening is suppressed within a range of chemical reaction rates. We then consider autocatalytic droplets, which catalyze the production of their own droplet material. Spontaneous nucleation of autocatalytic droplets is strongly suppressed and their emulsions are typically unstable. We show that autocatalytic droplets can be nucleated reliably and their emulsions stabilized by the help of chemically active cores, which catalyze the production of droplet material. In summary, different reaction schemes and catalytic cores can be used to stabilize emulsions and to control their properties.

  2. Metallic nanoshells on porphyrin-stabilized emulsions

    DOEpatents

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

    2013-10-29

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

  3. Kinetics of crosslinking in emulsion polymerization

    SciTech Connect

    Ghielmi, A.; Fiorentino, S.; Morbidelli, M.

    1996-12-31

    A mathematical model for evaluating the chain length distribution of nonlinear polymers produced in emulsions is presented. The heterogeneous emulsion polymerization process is described. The aim of the analysis is the distribution of active polymer chains and pairs of chains with a given growth time in latex particles in state.

  4. Flows of Wet Foamsand Concentrated Emulsions

    NASA Technical Reports Server (NTRS)

    Nemer, Martin B.

    2005-01-01

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

  5. Altering Emulsion Stability with Heterogeneous Surface Wettability

    PubMed Central

    Meng, Qiang; Zhang, Yali; Li, Jiang; Lammertink, Rob G. H.; Chen, Haosheng; Tsai, Peichun Amy

    2016-01-01

    Emulsions–liquid droplets dispersed in another immiscible liquid–are widely used in a broad spectrum of applications, including food, personal care, agrochemical, and pharmaceutical products. Emulsions are also commonly present in natural crude oil, hampering the production and quality of petroleum fuels. The stability of emulsions plays a crucial role in their applications, but controlling the stability without external driving forces has been proven to be difficult. Here we show how heterogeneous surface wettability can alter the stability and dynamics of oil-in-water emulsions, generated by a co-flow microfluidic device. We designed a useful methodology that can modify a micro-capillary of desired heterogeneous wettability (e.g., alternating hydrophilic and hydrophobic regions) without changing the hydraulic diameter. We subsequently investigated the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion. The experimental data revealed a universal critical timescale of advective emulsions, above which the microfluidic emulsions remain stable and intact, whereas below they become adhesive or inverse. A simple theoretical model based on a force balance can be used to explain this critical transition of emulsion dynamics, depending on the droplet size and the Capillary number–the ratio of viscous to surface effects. These results give insight into how to control the stability and dynamics of emulsions in microfluidics with flow velocity and different wettability. PMID:27256703

  6. Altering Emulsion Stability with Heterogeneous Surface Wettability

    NASA Astrophysics Data System (ADS)

    Meng, Qiang; Zhang, Yali; Li, Jiang; Lammertink, Rob G. H.; Chen, Haosheng; Tsai, Peichun Amy

    2016-06-01

    Emulsions–liquid droplets dispersed in another immiscible liquid–are widely used in a broad spectrum of applications, including food, personal care, agrochemical, and pharmaceutical products. Emulsions are also commonly present in natural crude oil, hampering the production and quality of petroleum fuels. The stability of emulsions plays a crucial role in their applications, but controlling the stability without external driving forces has been proven to be difficult. Here we show how heterogeneous surface wettability can alter the stability and dynamics of oil-in-water emulsions, generated by a co-flow microfluidic device. We designed a useful methodology that can modify a micro-capillary of desired heterogeneous wettability (e.g., alternating hydrophilic and hydrophobic regions) without changing the hydraulic diameter. We subsequently investigated the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion. The experimental data revealed a universal critical timescale of advective emulsions, above which the microfluidic emulsions remain stable and intact, whereas below they become adhesive or inverse. A simple theoretical model based on a force balance can be used to explain this critical transition of emulsion dynamics, depending on the droplet size and the Capillary number–the ratio of viscous to surface effects. These results give insight into how to control the stability and dynamics of emulsions in microfluidics with flow velocity and different wettability.

  7. Polymerization in emulsion microdroplet reactors

    NASA Astrophysics Data System (ADS)

    Carroll, Nick J.

    The goal of this research project is to utilize emulsion droplets as chemical reactors for execution of complex polymerization chemistries to develop unique and functional particle materials. Emulsions are dispersions of immiscible fluids where one fluid usually exists in the form of drops. Not surprisingly, if a liquid-to-solid chemical reaction proceeds to completion within these drops, the resultant solid particles will possess the shape and relative size distribution of the drops. The two immiscible liquid phases required for emulsion polymerization provide unique and complex chemical and physical environments suitable for the engineering of novel materials. The development of novel non-ionic fluorosurfactants allows fluorocarbon oils to be used as the continuous phase in a water-free emulsion. Such emulsions enable the encapsulation of almost any hydrocarbon compound in droplets that may be used as separate compartments for water-sensitive syntheses. Here, we exemplify the promise of this approach by suspension polymerization of polyurethanes (PU), in which the liquid precursor is emulsified into droplets that are then converted 1:1 into polymer particles. The stability of the droplets against coalescence upon removal of the continuous phase by evaporation confirms the formation of solid PU particles. These results prove that the water-free environment of fluorocarbon based emulsions enables high conversion. We produce monodisperse, cross-linked, and fluorescently labeled PU-latexes with controllable mesh size through microfluidic emulsification in a simple one-step process. A novel method for the fabrication of monodisperse mesoporous silica particles is presented. It is based on the formation of well-defined equally sized emulsion droplets using a microfluidic approach. The droplets contain the silica precursor/surfactant solution and are suspended in hexadecane as the continuous oil phase. The solvent is then expelled from the droplets, leading to

  8. Non-aqueous Isorefractive Pickering Emulsions

    PubMed Central

    2015-01-01

    Non-aqueous Pickering emulsions of 16–240 μm diameter have been prepared using diblock copolymer worms with ethylene glycol as the droplet phase and an n-alkane as the continuous phase. Initial studies using n-dodecane resulted in stable emulsions that were significantly less turbid than conventional water-in-oil emulsions. This is attributed to the rather similar refractive indices of the latter two phases. By utilizing n-tetradecane as an alternative oil that almost precisely matches the refractive index of ethylene glycol, almost isorefractive ethylene glycol-in-n-tetradecane Pickering emulsions can be prepared. The droplet diameter and transparency of such emulsions can be systematically varied by adjusting the worm copolymer concentration. PMID:25844544

  9. Aging mechanism in model Pickering emulsion

    NASA Astrophysics Data System (ADS)

    Fouilloux, Sarah; Malloggi, Florent; Daillant, Jean; Thill, Antoine

    We study the stability of a model Pickering emulsion system. A special counter-flow microfluidics set-up was used to prepare monodisperse Pickering emulsions, with oil droplets in water. The wettability of the monodisperse silica nanoparticles (NPs) could be tuned by surface grafting and the surface coverage of the droplets was controlled using the microfluidics setup. A surface coverage as low as 23$\\%$ is enough to stabilize the emulsions and we evidence a new regime of Pickering emulsion stability where the surface coverage of emulsion droplets of constant size increases in time, in coexistence with a large amount of dispersed phase. Our results demonstrate that the previously observed limited coalescence regime where surface coverage tends to control the average size of the final droplets must be put in a broader perspective.

  10. Destabilization of emulsions by natural minerals.

    PubMed

    Yuan, Songhu; Tong, Man; Wu, Gaoming

    2011-09-15

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

  11. Emulsion based cast booster - a priming system

    SciTech Connect

    Gupta, R.N.; Mishra, A.K.

    2005-07-01

    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.

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

    PubMed

    Fox, Garey A; Medina, Victor F

    2005-05-15

    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

  13. Dynamical and structural signatures of the glass transition in emulsions

    NASA Astrophysics Data System (ADS)

    Zhang, Chi; Gnan, Nicoletta; Mason, Thomas G.; Zaccarelli, Emanuela; Scheffold, Frank

    2016-09-01

    We investigate structural and dynamical properties of moderately polydisperse emulsions across an extended range of droplet volume fractions ϕ, encompassing fluid and glassy states up to jamming. Combining experiments and simulations, we show that when ϕ approaches the glass transition volume fraction {φg} , dynamical heterogeneities and amorphous order arise within the emulsion. In particular, we find an increasing number of clusters of particles having five-fold symmetry (i.e. the so-called locally favoured structures, LFS) as ϕ approaches {φg} , saturating to a roughly constant value in the glassy regime. However, contrary to previous studies, we do not observe a corresponding growth of medium-range crystalline order; instead, the emergence of LFS is decoupled from the appearance of more ordered regions in our system. We also find that the static correlation lengths associated with the LFS and with the fastest particles can be successfully related to the relaxation time of the system. By contrast, this does not hold for the length associated with the orientational order. Our study reveals the existence of a link between dynamics and structure close to the glass transition even in the absence of crystalline precursors or crystallization. Furthermore, the quantitative agreement between our confocal microscopy experiments and Brownian dynamics simulations indicates that emulsions are and will continue to be important model systems for the investigation of the glass transition and beyond.

  14. Arresting relaxation in Pickering Emulsions

    NASA Astrophysics Data System (ADS)

    Atherton, Tim; Burke, Chris

    2015-03-01

    Pickering emulsions consist of droplets of one fluid dispersed in a host fluid and stabilized by colloidal particles absorbed at the fluid-fluid interface. Everyday materials such as crude oil and food products like salad dressing are examples of these materials. Particles can stabilize non spherical droplet shapes in these emulsions through the following sequence: first, an isolated droplet is deformed, e.g. by an electric field, increasing the surface area above the equilibrium value; additional particles are then adsorbed to the interface reducing the surface tension. The droplet is then allowed to relax toward a sphere. If more particles were adsorbed than can be accommodated by the surface area of the spherical ground state, relaxation of the droplet is arrested at some non-spherical shape. Because the energetic cost of removing adsorbed colloids exceeds the interfacial driving force, these configurations can remain stable over long timescales. In this presentation, we present a computational study of the ordering present in anisotropic droplets produced through the mechanism of arrested relaxation and discuss the interplay between the geometry of the droplet, the dynamical process that produced it, and the structure of the defects observed.

  15. [On bitumen emulsions in water].

    PubMed

    Rivas, Hercilio; Gutierrez, Xiomara; Silva, Felix; Chirinos, Manuel

    2003-01-01

    The most important factors, controlling the process of emulsification of highly viscous hydrocarbons in water, which are responsible for keeping the stability and other properties of these systems, are discused in this article. The effect of non-ionic surfactants, such as nonil phenol ethoxilated compounds on the interfacial behavior of bitumen/water systems is analyzed. The effect of the natural surfactants in presence or in absence of electrolytes is also analyzed. The procedures followed in order to obtain the optimal conditions of formulation and formation of bitumen in water emulsions, are discussed and the effect of some parameters on the mean droplet diameter and distribution are also considered. It was found that keeping constant mixing speed and time of mixing, the mean droplet diameter decreases as the bitumen concentration increases. Emulsion stability, which can be monitored by following the changes in mean droplet diameters and viscosity as a function of the storage time, is deeply affected by the type and concentration of surfactant.

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

    PubMed

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

    2012-08-01

    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-γ 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.

  17. Effect of ultrasonic frequency on separation of water from heavy crude oil emulsion using ultrasonic baths.

    PubMed

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

    2017-03-01

    In this work, a comprehensive study was performed for the evaluation of ultrasound (US) frequency for demulsification of crude oil emulsions. Experiments were performed using ultrasonic baths operating at the following frequencies: 25, 35, 45, 130, 582, 862 and 1146kHz. Synthetic water-in-oil emulsions with 12%, 35% and 50% of water and medians of droplet size distribution (DSD, D(0.5)) of 5, 10 and 25μm were prepared using a heavy crude oil (API density of 19). Crude oil demulsification was achieved at frequencies in the range of 25-45kHz for all tested emulsions. When frequencies higher than 45kHz were applied, no changes in the characteristics of the crude oil emulsions were observed. Demulsification efficiencies of about 65% were achieved at a frequency of 45kHz after 15min of US application (emulsions with original water content of 50% and D(0.5)=10μm). An important aspect is that no addition of chemical demulsifiers was performed, and the demulsification efficiency was considered high, taking into account that the results were obtained using a non-conventional crude oil. Contrary to the normal application of low-frequency US that has been used for emulsification, the proposed approach seems to be a promising technology for water removal from crude oil emulsions.

  18. Surface Interaction of Water-in-Oil Emulsion Droplets with Interfacially Active Asphaltenes.

    PubMed

    Shi, Chen; Zhang, Ling; Xie, Lei; Lu, Xi; Liu, Qingxia; He, Jiajun; Mantilla, Cesar A; Van den Berg, Frans G A; Zeng, Hongbo

    2017-02-07

    Adsorption of interfacially active components at the water/oil interface plays critical roles in determining the properties and behaviors of emulsion droplets. In this study, the droplet probe atomic force microscopy (AFM) technique was applied, for the first time, to quantitatively study the interaction mechanism between water-in-oil (W/O) emulsion droplets with interfacially adsorbed asphaltenes. The behaviors and stability of W/O emulsion droplets were demonstrated to be significantly influenced by the asphaltene concentration of organic solution where the emulsions were aged, aging time, force load, contact time, and solvent type. Bare water droplets could readily coalesce with each other in oil (i.e., toluene), while interfacially adsorbed asphaltenes could sterically inhibit droplet coalescence and induce interfacial adhesion during separation of the water droplets. For low asphaltene concentration cases, the adhesion increased with increasing asphaltene concentration (≤100 mg/L), but it significantly decreased at relatively high asphaltene concentration (e.g., 500 mg/L). Experiments in Heptol (i.e., mixture of toluene and heptane) showed that the addition of a poor solvent for asphaltenes (e.g., heptane) could enhance the interfacial adhesion between emulsion droplets at relatively low asphaltene concentration but could weaken the adhesion at relatively high asphaltene concentration. This work has quantified the interactions between W/O emulsion droplets with interfacially adsorbed asphaltenes, and the results provide useful implications into the stabilization mechanisms of W/O emulsions in oil production. The methodology in this work can be readily extended to other W/O emulsion systems with interfacially active components.

  19. Heat Transfer in Boiling Dilute Emulsion with Strong Buoyancy

    NASA Astrophysics Data System (ADS)

    Freeburg, Eric Thomas

    Little attention has been given to the boiling of emulsions compared to that of boiling in pure liquids. The advantages of using emulsions as a heat transfer agent were first discovered in the 1970s and several interesting features have since been studied by few researchers. Early research focuses primarily on pool and flow boiling and looks to determine a mechanism by which the boiling process occurs. This thesis looks at the boiling of dilute emulsions in fluids with strong buoyant forces. The boiling of dilute emulsions presents many favorable characteristics that make it an ideal agent for heat transfer. High heat flux electronics, such as those seen in avionics equipment, produce high heat fluxes of 100 W/cm2 or more, but must be maintained at low temperatures. So far, research on single phase convection and flow boiling in small diameter channels have yet to provide an adequate solution. Emulsions allow the engineer to tailor the solution to the specific problem. The fluid can be customized to retain the high thermal conductivity and specific heat capacity of the continuous phase while enhancing the heat transfer coefficient through boiling of the dispersed phase component. Heat transfer experiments were carried out with FC-72 in water emulsions. FC-72 has a saturation temperature of 56 °C, far below that of water. The parameters were varied as follows: 0% ≤ epsilon ≤ 1% and 1.82 x 1012 ≤ RaH ≤ 4.42 x 1012. Surface temperatures along the heated surface reached temperature that were 20 °C in excess of the dispersed phase saturation temperature. An increase of ˜20% was seen in the average Nusselt numbers at the highest Rayleigh numbers. Holography was used to obtain images of individual and multiple FC-72 droplets in the boundary layer next to the heated surface. The droplet diameters ranged from 0.5 mm to 1.3 mm. The Magnus effect was observed when larger individual droplets were injected into the boundary layer, causing the droplets to be pushed

  20. Emulsion package and method of mixing the emulsion

    SciTech Connect

    Snyder, R.G.; Brenneman, S.; Clancy, J.J.

    1984-08-28

    A coal tar emulsion driveway sealer is packaged in a sealed bag. The volume of sealer is less than half the capacity of the bag and the bag is substantially completely evacuated but for the sealer. The separated sealer is mixed by compressing the sides of the bag to induce turbulent flow of the paste and liquid for hydraulic mixing thereof. The sealer may be dispensed at a controlled rate without spattering by cutting a corner from the bag to provide a pour spout. The bag with the sealer may be contained in a carton. The bag membrane comprises an aluminum layer vapor deposited on polyester. Those two layers are sandwiched between layers of EVA copolymer.

  1. Ethylcellulose: a new type of emulsion stabilizer.

    PubMed

    Melzer, Eva; Kreuter, Jörg; Daniels, Rolf

    2003-07-01

    Cellulose ethers, in particular hypromellose, represent an interesting alternative when emulsions have to be stabilized avoiding conventional low molecular weight surfactants. So far this option has been only described for the formulation of oil-in-water (o/w) emulsions. Since surfactant-free water-in-oil (w/o) emulsions seem to be also attractive as drug carriers, ethyl cellulose, an oil-soluble cellulose derivative, was studied for its ability to stabilize w/o emulsions. Measurements of the interfacial tension confirmed that ethylcellulose was positively adsorbed at the water/oil interface with diverse lipids. Appearance of model emulsions was dependent on the processing temperature. At low temperatures (15 degrees C) cream-like o/w emulsions were obtained. Processing at 30 degrees C yielded fluid w/o-lotions. Investigation of the microstructure showed that the surface of the emulsion droplets was covered with particles which formed a mechanical barrier. These colloidal particles were shown to be a precipitate of ethylcellulose which forms when the polymer which was dissolved in the lipid phase comes into contact with water. Thus, ethylcellulose was demonstrated to represent a new type of particulate polymeric emulsifier.

  2. High acyl gellan as an emulsion stabilizer.

    PubMed

    Vilela, Joice Aline Pires; da Cunha, Rosiane Lopes

    2016-03-30

    High acyl gellan (0.01-0.2% w/w) was used as stabilizer in oil in water emulsions containing 30% (w/w) of sunflower oil and prepared under different process conditions. Stable emulsions to phase separation could be obtained using high acyl gellan (HA) content above 0.05% (w/w), while low acyl gellan (LA) prepared at the same conditions could not stabilize emulsions. Emulsions properties depended on the process used to mix the oil and gellan dispersion since high pressure homogenization favored stabilization while very high energy density applied by ultrasound led to systems destabilization. Emulsions prepared using high pressure homogenization showed zeta potential values ranging from -50 up to -59 mV, suggesting that electrostatic repulsion could be contributing to the systems stability. Rheological properties of continuous phase were also responsible for emulsions stabilization, since HA gellan dispersions showed high viscosity and gel-like behavior. The high viscosity of the continuous phase could be associated to the presence of high acyl gellan microgels/aggregates. Disentanglement of these aggregates performed by ultrasound strongly decreased the viscosity and consequently affected the emulsions behavior, reducing the stability to phase separation.

  3. Using emulsion inversion in industrial processes.

    PubMed

    Salager, Jean-Louis; Forgiarini, Ana; Márquez, Laura; Peña, Alejandro; Pizzino, Aldo; Rodriguez, María P; Rondón-González, Marianna

    2004-05-20

    Emulsion inversion is a complex phenomenon, often perceived as an instability that is essentially uncontrollable, although many industrial processes make use of it. A research effort that started 2 decades ago has provided the two-dimensional and three-dimensional description, the categorization and the theoretical interpretation of the different kinds of emulsion inversion. A clear-cut phenomenological approach is currently available for understanding its characteristics, the factors that influence it and control it, the importance of fine-tuning the emulsification protocol, and the crucial occurrence of organized structures such as liquid crystals or multiple emulsions. The current know-how is used to analyze some industrial processes involving emulsion inversion, e.g. the attainment of a fine nutrient or cosmetic emulsion by temperature or formulation-induced transitional inversion, the preparation of a silicone oil emulsion by catastrophic phase inversion, the manufacture of a viscous polymer latex by combined inversion and the spontaneous but enigmatic inversion of emulsions used in metal working operations such as lathing or lamination.

  4. Enhancement of the antimicrobial properties of bacteriophage-K via stabilization using oil-in-water nano-emulsions.

    PubMed

    Esteban, Patricia Perez; Alves, Diana R; Enright, Mark C; Bean, Jessica E; Gaudion, Alison; Jenkins, A T A; Young, Amber E R; Arnot, Tom C

    2014-01-01

    Bacteriophage therapy is a promising new treatment that may help overcome the threat posed by antibiotic-resistant pathogenic bacteria, which are increasingly identified in hospitalized patients. The development of biocompatible and sustainable vehicles for incorporation of viable bacterial viruses into a wound dressing is a promising alternative. This article evaluates the antimicrobial efficacy of Bacteriophage K against Staphylococcus aureus over time, when stabilized and delivered via an oil-in-water nano-emulsion. Nano-emulsions were formulated via thermal phase inversion emulsification, and then bacterial growth was challenged with either native emulsion, or emulsion combined with Bacteriophage K. Bacteriophage infectivity, and the influence of storage time of the preparation, were assessed by turbidity measurements of bacterial samples. Newly prepared Bacteriophage K/nano-emulsion formulations have greater antimicrobial activity than freely suspended bacteriophage. The phage-loaded emulsions caused rapid and complete bacterial death of three different strains of S. aureus. The same effect was observed for preparations that were either stored at room temperature (18-20°C), or chilled at 4°C, for up to 10 days of storage. A response surface design of experiments was used to gain insight on the relative effects of the emulsion formulation on bacterial growth and phage lytic activity. More diluted emulsions had a less significant effect on bacterial growth, and diluted bacteriophage-emulsion preparations yielded greater antibacterial activity. The enhancement of bacteriophage activity when delivered via nano-emulsions is yet to be reported. This prompts further investigation into the use of these formulations for the development of novel anti-microbial wound management strategies.

  5. Pump safety tests regarding emulsion explosives

    SciTech Connect

    Perlid, H.

    1996-12-31

    In the handling of emulsion explosives pumping is a key operation. A number of serious accidents has shown that pumping can be a risky operation and should be carefully considered and investigated. This is the background behind a series of pump tests carried out by Nitro Nobel. This paper refers to pump safety tests with an eccentric screw pump (progressive cavity) and emulsion explosives. A selection of emulsions unsensitized as well as sensitized were tested. The tests were performed in a circulation system against dead head and as dry pumping.

  6. The Morphology of Emulsion Polymerized Latex Particles

    DOE R&D Accomplishments Database

    Wignall, G. D.; Ramakrishnan, V. R.; Linne, M. A.; Klein, A.; Sperling, L. H.; Wai, M. P.; Gelman, R. A.; Fatica, M. G.; Hoerl, R. H.; Fisher, L. W.

    1987-11-01

    Under monomer starved feed conditions, emulsion polymerization of perdeuterated methyl methacrylate and styrene in the presence of preformed polymethylmethacrylate latexes resulted in particles with a core-shell morphology, as determined by small-angle neutron scattering (SANS) analysis for a hollow sphere. The locus of polymerization of the added deuterated monomer is therefore at the particle surface. In similar measurements a statistical copolymer of styrene and methyl methacrylate was used as seed particles for further polymerization of trideuteromethyl methacrylate. The resulting polymer latex was again shown to have a core-shell morphological structure as determined by SANS. SANS experiments were also undertaken on polystyrene latexes polymerized by equilibrium swelling methods, with deuterated polymer forming the first or second step. The experiments covered a molecular weight range of 6 x 10{sup 4} 10{sup 6} the molecular weights are consistent with the experimental errors, indicating that the deuterium labeled molecules are randomly distributed in the latex. These results led to the finding that the polymer chains were constrained in the latex particles by factors of 2 to 4 from the relaxed coil dimensions. For M < 10{sup 6} g/mol SANS gave zero angle scattering intensities much higher than expected on the basis of a random distribution of labeled molecules. Several models were examined, including the possible development of core-shell structures at lower molecular weights.

  7. The morphology of emulsion polymerized latex particles

    SciTech Connect

    Wignall, G.D.; Ramakrishnan, V.R.; Linne, M.A.; Klein, A.; Sperling, L.H.; Wai, M.P.; Gelman, R.A.; Fatica, M.G.; Hoerl, R.H.; Fisher, L.W.

    1987-11-01

    Under monomer starved feed conditions, emulsion polymerization of perdeuterated methyl methacrylate and styrene in the presence of preformed polymethylmethacrylate latexes resulted in particles with a core-shell morphology, as determined by small-angle neutron scattering (SANS) analysis for a hollow sphere. The locus of polymerization of the added deuterated monomer is therefore at the particle surface. In similar measurements a statistical copolymer of styrene and methyl methacrylate was used as seed particles for further polymerization of trideuteromethyl methacrylate. The resulting polymer latex was again shown to have a core-shell morphological structre as determined by SANS. SANS experiments were also undertaken on polystyrene latexes polymerized by equilibrium swelling methods, with deuterated polymer forming the first or second step. The experiments covered a molecular weight range of 6 x 10/sup 4/ < M < 6 x 10/sup 6/ g/mol. For M > 10/sup 6/ the molecular weights are consistent with the experimental errors, indicating that the deuterium labeled molecules are randomly distributed in the latex. These results led to the finding that the polymer chains were constrained in the latex particles by factors of 2 to 4 from the relaxed coil dimensions. For M < 10/sup 6/ g/mol SANS gave zero angle scattering intensities much higher than expected on the basis of a random distribution of labeled molecules. Several models were examined, including the possible development of core-shell structures at lower molecular weights. 25 refs., 6 figs., 3 tabs.

  8. Decompressing Emulsion Droplets Favors Coalescence

    NASA Astrophysics Data System (ADS)

    Bremond, Nicolas; Thiam, Abdou R.; Bibette, Jérôme

    2008-01-01

    The destabilization process of an emulsion under flow is investigated in a microfluidic device. The experimental approach enables us to generate a periodic train of droplet pairs, and thus to isolate and analyze the basic step of the destabilization, namely, the coalescence of two droplets which collide. We demonstrate a counterintuitive phenomenon: coalescence occurs during the separation phase and not during the impact. Separation induces the formation of two facing nipples in the contact area that hastens the connection of the interfaces prior to fusion. Moreover, droplet pairs initially stabilized by surfactants can be destabilized by forcing the separation. Finally, we note that the fusion mechanism is responsible for a cascade of coalescence events in a compact system of droplets where the separation is driven by surface tension.

  9. Dielectrophoresis of reverse phase emulsions.

    PubMed

    Flores-Rodriguez, N; Bryning, Z; Markx, G H

    2005-08-01

    Reverse miniemulsions, emulsions of droplets of size 200 nm-1 microm of a polar liquid dispersed in an apolar continuous liquid phase, exhibit strong electrokinetic responses in low-frequency electric fields. The electrokinetic behaviour of a reverse miniemulsion, previously developed for use as electronic paper, has been investigated under static and flow conditions, in uniform and non-uniform electric fields. Results reveal that when using frequencies lower than 10 Hz strong aggregation of the droplets occurs. In uniform electric fields, under static conditions, droplets reversibly aggregate into honeycomb-like or irregular aggregates. Under flow conditions, droplets aggregate into approximately equidistant streams. In non-uniform electric fields the droplets reversibly aggregate in high-field regions, and can be guided along regions of high field strength in a flow. The potential of the technique for the formation of structured materials is discussed.

  10. Future Experiments with HADES at FAIR

    SciTech Connect

    Tlusty, P.

    2010-12-28

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

  11. Aging properties of Kodak type 101 emulsions

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  12. Multi-body coalescence in Pickering emulsions.

    PubMed

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

    2015-01-12

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

  13. Scanning microbeam small-angle X-ray diffraction study of interfacial heterogeneous crystallization of fat crystals in oil-in-water emulsion droplets.

    PubMed

    Arima, S; Ueno, S; Ogawa, A; Sato, K

    2009-09-01

    We performed scanning microbeam small-angle X-ray diffraction (micro-SAXD) experiments, differential scanning calorimetry (DSC) analysis, and optical microscopic observation of palm mid fraction (PMF) crystals in oil-in-water emulsion droplets. The scanning micro-SAXD experiment was performed by irradiating a synchrotron radiation X-ray microbeam having an area of 5 x 5 microm(2) onto different positions on a 50 microm diameter emulsion droplet after the crystallization of PMF by chilling the emulsion at 5 degrees C. The micro-SAXD patterns were recorded with a two-dimensional (2D) detector, which enabled spatial analysis of polymorphic structures and the orientation of lamella planes of PMF crystals at different positions inside the emulsion droplet. Particular attention was paid to compare the crystallization of PMF in two types of emulsion droplets, hydrophilic polyoxyethylene sorbitan mono-oleate (Tween 80) alone (Tween 80 emulsion) and Tween 80 and hydrophobic sucrose palmitic acid oligoester (P-170) (Tween 80+P-170 emulsion). The DSC study revealed that the PMF crystallization temperature in the Tween 80+P-170 emulsion droplets increased by 3 degrees C compared to that of the Tween 80 emulsion because of the effects of the P-170 additive in promoting PMF crystallization. The micro-SAXD studies revealed the following results. (1) The lamella planes of PMF crystals near the outer edges of the droplet in the Tween 80+P-170 emulsion were mostly parallel to an oil-water interface, whereas the lamella planes of PMF crystals were not always aligned with the oil-water interface in the Tween 80 emulsion droplet. (2) The degree of orientation of the lamellar planes of PMF crystals, which was evaluated from the values of full width at half-maximum of 2D micro-SAXD patterns with respect to azimuthal angle extension, was remarkably higher in the Tween 80+P-170 emulsion than in the Tween 80 emulsion. (3) Polymorphic transformation of PMF from alpha to beta' in the Tween 80

  14. Surfactant-enhanced cellulose nanocrystal Pickering emulsions.

    PubMed

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

    2015-02-01

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

  15. Shear-stabilized emulsion flooding process

    SciTech Connect

    Carpenter, C.W.; Reed, R.L.

    1982-06-29

    Additional amounts of crude oil are recovered from a subterranean formation by flooding with a translucent emulsion comprising an upper- or middle-phase microemulsion as an external phase and a polymer-containing brine solution as an internal phase. The translucent emulsion tends to coalesce into its component phases under conditions of no shear, but is stabilized by low shears such as those imposed on fluids flowing through a subterranean formation.

  16. Hexagonal phase based gel-emulsion (O/H1 gel-emulsion): formation and rheology.

    PubMed

    Alam, Mohammad Mydul; Aramaki, Kenji

    2008-11-04

    The formation, stability, and rheological behavior of a hexagonal phase based gel-emulsion (O/H1 gel-emulsion) have been studied in water/C12EO8/hydrocarbon oil systems. A partial phase behavior study indicates that the oil nature has no effect on the phase sequences in the ternary phase diagram of water/C12EO8/oil systems but the domain size of the phases or the oil solubilization capacity considerably changes with oil nature. Excess oil is in equilibrium with the hexagonal phase (H1) in the ternary phase diagram in the H1+O region. The O/H1 gel-emulsion was prepared (formation) and kept at 25 degrees C to check stability. It has been found that the formation and stability of the O/H1 gel-emulsion depends on the oil nature. After 2 min observation (formation), the results show that short chain linear hydrocarbon oils (heptane, octane) are more apt to form a O/H1 gel-emulsion compared to long chain linear hydrocarbon oils (tetradecane, hexadecane), though the stability is not good enough in either system, that is, oil separates within 24 h. Nevertheless, the formation and stability of the O/H1 gel-emulsion is appreciably increased in squalane and liquid paraffin. It is surmised that the high transition temperature of the H1+O phase and the presence of a bicontinuous cubic phase (V1) might hamper the formation of a gel-emulsion. It has been pointed out that the solubilization of oil in the H1 phase could be related to emulsion stability. On the other hand, the oil nature has little or no effect on the formation and stability of a cubic phase based gel-emulsion (O/I1 gel-emulsion). From rheological measurements, it has found that the rheogram of the O/H1 gel-emulsion indicates gel-type structure and shows shear thinning behavior similar to the case of the O/I1 gel-emulsion. Rheological data infer that the O/I1 gel-emulsion is more viscous than the O/H1 gel-emulsion at room temperature but the O/H1 gel-emulsion shows consistency at elevated temperature.

  17. Pickering emulsions stabilized by charged nanoparticles.

    PubMed

    Ridel, Laure; Bolzinger, Marie-Alexandrine; Gilon-Delepine, Nicole; Dugas, Pierre-Yves; Chevalier, Yves

    2016-09-28

    The stabilization of o/w Pickering emulsions in cases of weak adsorption of solid particles at the surface of oil droplets is addressed. Though the adsorption is usually very strong and irreversible when partial wetting conditions are fulfilled, electrostatic repulsions between charged solid particles act against the adsorption. The regime of weak adsorption was reached using charged silica nanoparticles at high pH and low ionic strength. O/w Pickering emulsions of the diisopropyl adipate oil were stabilized by colloidal nanoparticles of Ludox® AS40 consisting of non-aggregated particles of bare silica (hydrophilic). The combination of stability assessment, droplet size and electrokinetic potential measurements at various pH values, adsorption isotherms and cryo-SEM observations of the adsorbed layers disclosed the specificities of the stabilization of Pickering emulsions by adsorption of solid nanoparticles against strong electrostatic repulsions. Not only the long-term stability of emulsions was poor under strong electrostatic repulsions at high pH, but emulsification failed since full dispersion of oil could not be achieved. Emulsion stability was ensured by decreasing electrostatic repulsions by lowering the pH from 9 to 3. Stable emulsions were stabilized by a monolayer of silica particles at 54% coverage of the oil droplet surface at low silica content and an adsorption regime as multilayers was reached at higher concentrations of silica although there was no aggregation of silica in the bulk aqueous phase.

  18. Conditions for equilibrium solid-stabilized emulsions.

    PubMed

    Kraft, Daniela J; de Folter, Julius W J; Luigjes, Bob; Castillo, Sonja I R; Sacanna, Stefano; Philipse, Albert P; Kegel, Willem K

    2010-08-19

    Particular types of solid-stabilized emulsions can be thermodynamically stable as evidenced by their spontaneous formation and monodisperse droplet size, which only depends on system parameters. Here, we investigate the generality of these equilibrium solid-stabilized emulsions with respect to the basic constituents: aqueous phase with ions, oil, and stabilizing particles. From systematic variations of these constituents, we identify general conditions for the spontaneous formation of monodisperse solid-stabilized emulsions droplets. We conclude that emulsion stability is achieved by a combination of solid particles as well as amphiphilic ions adsorbed at the droplet surface, and low interfacial tensions of the bare oil-water interface of order 10 mN/m or below. Furthermore, preferential wetting of the colloidal particles by the oil phase is necessary for thermodynamic stability. We demonstrate the sufficiency of these basic requirements by extending the observed thermodynamic stability to emulsions of different compositions. Our findings point to a new class of colloid-stabilized meso-emulsions with a potentially high impact on industrial emulsification processes due to the associated large energy savings.

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

    PubMed Central

    Li, Yilei; Zhu, Zhencai; Chen, Guoan

    2014-01-01

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

  20. Bespoke contrast-matched diblock copolymer nanoparticles enable the rational design of highly transparent Pickering double emulsions

    NASA Astrophysics Data System (ADS)

    Rymaruk, Matthew J.; Thompson, Kate L.; Derry, Matthew J.; Warren, Nicholas J.; Ratcliffe, Liam P. D.; Williams, Clive N.; Brown, Steven L.; Armes, Steven P.

    2016-07-01

    We report the preparation of highly transparent oil-in-water Pickering emulsions using contrast-matched organic nanoparticles. This is achieved via addition of judicious amounts of either sucrose or glycerol to an aqueous dispersion of poly(glycerol monomethacrylate)56-poly(2,2,2-trifluoroethyl methacrylate)500 [PGMA-PTFEMA] diblock copolymer nanoparticles prior to high shear homogenization with an equal volume of n-dodecane. The resulting Pickering emulsions comprise polydisperse n-dodecane droplets of 20-100 μm diameter and exhibit up to 96% transmittance across the visible spectrum. In contrast, control experiments using non-contrast-matched poly(glycerol monomethacrylate)56-poly(benzyl methacrylate)300 [PGMA56-PBzMA300] diblock copolymer nanoparticles as a Pickering emulsifier only produced conventional highly turbid emulsions. Thus contrast-matching of the two immiscible phases is a necessary but not sufficient condition for the preparation of highly transparent Pickering emulsions: it is essential to use isorefractive nanoparticles in order to minimize light scattering. Furthermore, highly transparent oil-in-water-in-oil Pickering double emulsions can be obtained by homogenizing the contrast-matched oil-in-water Pickering emulsion prepared using the PGMA56-PTFEMA500 nanoparticles with a contrast-matched dispersion of hydrophobic poly(lauryl methacrylate)39-poly(2,2,2-trifluoroethyl methacrylate)800 [PLMA39-PTFEMA800] diblock copolymer nanoparticles in n-dodecane. Finally, we show that an isorefractive oil-in-water Pickering emulsion enables fluorescence spectroscopy to be used to monitor the transport of water-insoluble small molecules (pyrene and benzophenone) between n-dodecane droplets. Such transport is significantly less efficient than that observed for the equivalent isorefractive surfactant-stabilized emulsion. Conventional turbid emulsions do not enable such a comparison to be made because the intense light scattering leads to substantial spectral

  1. Impact of model fat emulsions on sensory perception using repeated spoon to spoon ingestion.

    PubMed

    Appelqvist, I A M; Poelman, A A M; Cochet-Broch, M; Delahunty, C M

    2016-06-01

    Eating is a dynamic behaviour, in which food interacts with the mechanical and physiological environment of the mouth. This dynamic interaction changes the oral surfaces leaving particles of food and building up a film on the oral surfaces, which may impact on the temporal perception during the eating experience. The effect of repeated spoon to spoon ingestion of oil in water emulsion products (2%-50% w/w oil) was evaluated using descriptive in-mouth and after swallowing sensory attributes. Descriptive sensory analysis indicated that fatty mouthfeel and afterfeel perception (measured post swallowing) increased with the number of spoonfuls for emulsions containing 50% fat. This effect is likely due to the build-up of oil droplet layers deposited on the mouth surfaces. There was an enhancement of fatty afterfeel intensity for 50% fat emulsions containing the more lipophilic aroma ethylhexanoate compared to ethyl butanoate, indicating a cross-modal interaction. No increase in these attributes from spoon to spoon was observed for the low oil emulsions; since most of the oil in the emulsion was swallowed and very little oil was likely to be left in the mouth. Sweetness perception increased as fat level increased in the emulsion due to an increase in the effective concentration of sugar in the aqueous phase. However, the sweetness perceived did not change from spoon to spoon, suggesting that any oil-droplets deposited on the oral surfaces did not form a complete barrier, restricting access of the sucrose to the taste buds. This study highlights the importance of measuring the dynamic nature of eating and demonstrated change in sensory perception occurring with repeated ingestion of model emulsions, which was likely due to a change in mouth environment.

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

    PubMed

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

    2014-08-12

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

  3. Bespoke contrast-matched diblock copolymer nanoparticles enable the rational design of highly transparent Pickering double emulsions.

    PubMed

    Rymaruk, Matthew J; Thompson, Kate L; Derry, Matthew J; Warren, Nicholas J; Ratcliffe, Liam P D; Williams, Clive N; Brown, Steven L; Armes, Steven P

    2016-08-14

    We report the preparation of highly transparent oil-in-water Pickering emulsions using contrast-matched organic nanoparticles. This is achieved via addition of judicious amounts of either sucrose or glycerol to an aqueous dispersion of poly(glycerol monomethacrylate)56-poly(2,2,2-trifluoroethyl methacrylate)500 [PGMA-PTFEMA] diblock copolymer nanoparticles prior to high shear homogenization with an equal volume of n-dodecane. The resulting Pickering emulsions comprise polydisperse n-dodecane droplets of 20-100 μm diameter and exhibit up to 96% transmittance across the visible spectrum. In contrast, control experiments using non-contrast-matched poly(glycerol monomethacrylate)56-poly(benzyl methacrylate)300 [PGMA56-PBzMA300] diblock copolymer nanoparticles as a Pickering emulsifier only produced conventional highly turbid emulsions. Thus contrast-matching of the two immiscible phases is a necessary but not sufficient condition for the preparation of highly transparent Pickering emulsions: it is essential to use isorefractive nanoparticles in order to minimize light scattering. Furthermore, highly transparent oil-in-water-in-oil Pickering double emulsions can be obtained by homogenizing the contrast-matched oil-in-water Pickering emulsion prepared using the PGMA56-PTFEMA500 nanoparticles with a contrast-matched dispersion of hydrophobic poly(lauryl methacrylate)39-poly(2,2,2-trifluoroethyl methacrylate)800 [PLMA39-PTFEMA800] diblock copolymer nanoparticles in n-dodecane. Finally, we show that an isorefractive oil-in-water Pickering emulsion enables fluorescence spectroscopy to be used to monitor the transport of water-insoluble small molecules (pyrene and benzophenone) between n-dodecane droplets. Such transport is significantly less efficient than that observed for the equivalent isorefractive surfactant-stabilized emulsion. Conventional turbid emulsions do not enable such a comparison to be made because the intense light scattering leads to substantial spectral

  4. Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber

    PubMed Central

    Choi, Yun-Sang; Kim, Young-Boong; Park, Jinhee

    2015-01-01

    This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back fat+3% BRF), T4 (30% back fat+6% BRF), and T15 (10% back fat+10% canola oil+2% BRF). Lower emulsion stability and higher apparent viscosity were observed in T1, T2, T3, T4, and T8 (20% back fat+3% BRF) compared to the control. Lower emulsion stability and higher hardness was detected in all treatments compared with the control, except T5 (20% back fat), T10 (10% back fat+10% canola oil+2% BRF), T11 (10% back fat+10% olive oil+2% BRF), T12 (10% back fat+10% grape seed oil+2% BRF), and T13 (10% back fat+10% soybean oil+2% BRF). This approach has been found particularly useful for highlighting differences among the emulsified properties in emulsion meat products. Thus, the results obtained with emulsion mapping are useful in making emulsified meat products of desired quality characteristics, partially replacing pork back fat with a mix of 10% back fat, 10% canola oil and 2% BRF was most similar to the control with 30% pork back fat. PMID:26761836

  5. The atomization of water-oil emulsions

    SciTech Connect

    Broniarz-Press, L.; Ochowiak, M.; Rozanski, J.; Woziwodzki, S.

    2009-09-15

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

  6. Kinetic Release of Alkalinity from Particle-Containing Oil-in-Water Emulsions

    NASA Astrophysics Data System (ADS)

    Muller, K.; Chapra, S. C.; Ramsburg, A.

    2014-12-01

    Oil-in-water emulsions are typically employed during remediation to promote biotic reduction of contaminants. Emulsions, however, hold promise for encapsulated delivery of many types of active ingredients required for successful site remediation or long-term site stewardship. Our research is currently focused on using alkalinity-containing particles held within oil-in-water emulsions to sustain control of subsurface pH. Here we describe results from laboratory experiments and mathematical modeling conducted to quantify the kinetics associated with the emulsion delivery and alkalinity release process. Kinetically stable oil-in-water emulsions containing (~60 nmCaCO3 or ~100 nm MgO particles) were previously developed using soybean oil and Gum Arabic as a stabilizing agent. Batch and column experiments were employed to assess the accessibility and release of the alkalinity from the emulsion. Successive additions of HCl were used in batch systems to produce several pH responses (pH rebounds) that were subsequently modeled to elucidate release mechanisms and rates for varying emulsion compositions and particle types. Initial results suggest that a linear-driving-force model is generally able to capture the release behavior in the batch system when the temporally-constant, lumped mass-transfer coefficient is scaled by the fraction of particle mass remaining within the droplets. This result suggests that the rate limiting step in the release process may be the interphase transfer of reactive species at the oil-water interface. 1-d column experiments were also completed in order to quantify the extent and rate of alkalinity release from emulsion droplets retained in a sandy medium. Alkalinity release from the retained droplets treated a pH 4 influent water for 25-60 pore volumes (the duration depended on particle type and mass loading), and the cessation in treatment corresponded to exhaustion of the particle mass held within the oil. Column experiments were simulated

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

    PubMed

    Sanfeld, Albert; Steinchen, Annie

    2008-07-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2009-02-01

    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.

  9. Direct current electrorheological stability determination of water-in-crude oil emulsions.

    PubMed

    Wang, Xiuyu; Alvarado, Vladimir

    2009-10-22

    Emulsion stability is a fundamental determination for separation technologies. We use the critical electric field (CEF) and viscosity changes in DC electrorheological (ER) experiments in dynamic mode to establish the level of 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. Our results show that CEF can be obtained through current measurements and viscosity drops resulting from emulsion structure breakdown, although viscosity changes are not always a good proxy of stability. This implies that electrorheology cannot be uncritically used for static stability determination of the CEF value. 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 response, 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.

  10. A disposable emulsion droplet generation lab chips driven by vacuum module for manipulation of blood cells.

    PubMed

    Chia-Hung Lee; Chien-Chong Hong

    2015-08-01

    This paper presents a novel disposable emulsion droplet generation lab chip driven by vacuum module for monodisperse emulsions generation and blood cell encapsulation. Emulsion droplet is a powerful tool in miniaturized analysis systems for high throughput processing. It shows great potential in chemical and biological reactions like speeding up the reaction and reducing the cost of reagents. Most research groups use syringe pumps providing positive pressure to drive the fluids. However, the long tubing connection and high cost make the microfluidic systems complicate and unsuitable for lab-on-a-chip (LOC) device. In this paper, our emulsion droplet generation lab chip with disposable vacuum module, made of shape memory polymer, provides a negative pressure to drive the fluids. This lab chip could achieve creating monodisperse emulsion droplets by manipulating two-phase microfluidic within 1 set of vacuum module and mini-heater. In the meantime, the waste is gathered into the cavity of vacuum module. This makes this lab chip safe while using biological samples. The vacuum module shows the advantages of compact, simple structure, and east-to-attach with the microfluidic device and great performance in the experiments.

  11. Dynamic film and interfacial tensions in emulsion and foam systems

    SciTech Connect

    Kim, Y.H.; Koczo, K.; Wasan, D.T.

    1997-03-01

    In concentrated fluid dispersions the liquid films are under dynamic conditions during film rupture or drainage. Aqueous foam films stabilized with sodium decylsulfonate and aqueous emulsion films stabilized with the nonionic Brij 58 surfactant were formed at the tip of a capillary and the film tension was measured under static and dynamic conditions. In the stress relaxation experiments the response of the film tension to a sudden film area expansion was studied. These experiments also allowed the direct measurement of the Gibbs film elasticity. In the dynamic film tension experiments, the film area was continuously increased by a constant rate and the dynamic film tension was monitored. The measured film tensions were compared with the interfacial tensions of the respective single air/water and oil/water interfaces, which were measured using the same radius of curvature, relative expansion, and expansion rate as in the film studies. It was found that under dynamic conditions the film tension is higher than twice the single interfacial tension (IFT) and a mechanism was suggested to explain the difference. When the film, initially at equilibrium, is expanded and the interfacial area increases, a substantial surfactant depletion occurs inside the film. As a result, the surfactant can be supplied only from the adjoining meniscus (Plateau border) by surface diffusion, and the film tension is controlled by the diffusion and adsorption of surfactant in the meniscus. The results have important implications for the stability and rheology of foams and emulsions with high dispersed phase ratios (polyhedral structure).

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

    NASA Astrophysics Data System (ADS)

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

    2009-12-01

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

  13. Shock compression and recovery of microorganism-loaded broths and an emulsion

    NASA Astrophysics Data System (ADS)

    Hazell, Paul; Beveridge, Cliff; Groves, Kathy

    2009-06-01

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

  14. Tuneable Rheological Properties of Fluorinated Pickering Emulsions

    NASA Astrophysics Data System (ADS)

    Chacon Orellana, Laura Andreina; Riechers, Birte; Caen, Ouriel; Baret, Jean-Christophe

    Pickering emulsions are an appealing approach to stabilize liquid-liquid dispersions without surfactants. Recently, amphiphilic silica nanoparticles have been proposed as an alternative to surfactants for droplet microfluidics applications, where aqueous drops are stabilized in fluorinated oils. This system, proved to be effective in preventing the leakage of resorufin, a model dye that was known to leak in surfactant-stabilized drops. The overall capabilities of droplet-based microfluidics technology is highly dependent on the dynamic properties of droplets, interfaces and emulsions. Therefore, fluorinated pickering emulsions dynamic properties need to be characterized, understood and controlled to be used as a substitute of already broadly studied emulsions for droplet microfluidics applications. In this study, fluorinated pickering emulsions have been found to behave as a Herschel Bulkley fluid, representing a challenge for common microfluidic operations as re-injection and sorting of droplets. We found that this behavior is controlled by the interaction between the interfacial properties of the particle-laden interface and the bulk properties of the two phases

  15. High pressure-resistant nonincendive emulsion explosive

    DOEpatents

    Ruhe, Thomas C.; Rao, Pilaka P.

    1994-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  17. Stimuli-responsive Pickering emulsions: recent advances and potential applications.

    PubMed

    Tang, Juntao; Quinlan, Patrick James; Tam, Kam Chiu

    2015-05-14

    Pickering emulsions possess many advantages over traditional surfactant stabilized emulsions. For example, Pickering emulsions impart better stability against coalescence and, in many cases, are biologically compatible and environmentally friendly. These characteristics open the door for their use in a variety of industries spanning petroleum, food, biomedicine, pharmaceuticals, and cosmetics. Depending on the application, rapid, but controlled stabilization and destabilization of an emulsion may be necessary. As a result, Pickering emulsions with stimuli-responsive properties have, in recent years, received a considerable amounts of attention. This paper provides a concise and comprehensive review of Pickering emulsion systems that possess the ability to respond to an array of external triggers, including pH, temperature, CO2 concentration, light intensity, ionic strength, and magnetic field. Potential applications for which stimuli-responsive Pickering emulsion systems would be of particular value, such as emulsion polymerization, enhanced oil recovery, catalyst recovery, and cosmetics, are discussed.

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

    ERIC Educational Resources Information Center

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

    2008-01-01

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

  19. Clinical applications of intravenous lipid emulsion therapy.

    PubMed

    Muller, Sam H; Diaz, James H; Kaye, Alan David

    2015-12-01

    Intravenous lipid emulsion (ILE; Intralipid) therapy, a standard treatment in local anesthetic toxicity, has demonstrated therapeutic efficacies for a number of different drug class-mediated toxicities. Some of these varied drug groups include antipsychotics, antidepressants, antiarrhythmics, and calcium channel blockers. To meet the objective of describing the growing number of indications for Intralipid therapy and any diverse effects and/or failures of Intralipid therapy in reversing multiple drug toxicities, we queried several Internet search engines with the key words "intravenous lipid emulsion therapy," "Intralipid," "lipid emulsion," and "local anesthetic systemic toxicity," resulting in the identification of 31 case reports for descriptive analysis. These case reports included 49 separate drug overdose cases involving ten separate drug classes which were successfully reversed with Intralipid. The education of clinicians regarding the beneficial and varied roles of Intralipid therapy in different clinical settings is warranted, particularly in terms of the potential for Intralipid therapy to reverse the toxicities of non-local anesthetic drugs.

  20. Multi-body coalescence in Pickering emulsions

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

  1. Forces acting in quasi 2d emulsions

    NASA Astrophysics Data System (ADS)

    Orellana, Carlos; Lowensohn, Janna; Weeks, Eric

    We study the forces in a quasi two dimensional emulsion system. Our samples are oil-in-water emulsions confined between two close-spaced parallel plates, so that the oil droplets are deformed into pancake shapes. By means of microscopy, we measure the droplet positions and their deformation, which we can relate to the contact forces due to surface tension. We improve over prior work in our lab, achieving a better force resolution. We use this result to measure and calibrate the viscous forces acting in our system, which fully determine all the forces on the droplets. Our results can be applied to study static configurations of emulsion, as well as faster flows.

  2. Shear dynamics of an inverted nematic emulsion.

    PubMed

    Tiribocchi, A; Da Re, M; Marenduzzo, D; Orlandini, E

    2016-10-04

    Here we study theoretically the dynamics of a 2D and a 3D isotropic droplet in a nematic liquid crystal under a shear flow. We find a large repertoire of possible nonequilibrium steady states as a function of the shear rate and of the anchoring of the nematic director field at the droplet surface. We first discuss homeotropic anchoring. For weak anchoring, we recover the typical behaviour of a sheared isotropic droplet in a binary fluid, which rotates, stretches and can be broken by the applied flow. For intermediate anchoring, new possibilities arise due to elastic effects in the nematic fluid. We find that in this regime the 2D droplet can tilt and move in the flow, or tumble incessantly at the centre of the channel. For sufficiently strong anchoring, finally, one or both of the topological defects which form close to the surface of the isotropic droplet in equilibrium detach from it and get dragged deep into the nematic state by the flow. In 3D, instead, the Saturn ring associated with the normal anchoring disclination line can be deformed and shifted downstream by the flow, but remains always localized in the proximity of the droplet, at least for the parameter range we explored. Tangential anchoring in 2D leads to a different dynamic response, as the boojum defects characteristic of this situation can unbind from the droplet under a weaker shear with respect to the normal anchoring case. Our results should stimulate further experiments with inverted liquid crystal emulsions under shear, as most of the predictions can be testable in principle by monitoring the evolution of liquid crystalline orientation patterns or by tracking the position and shape of the droplet over time.

  3. Phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs).

    PubMed

    Zhang, Tao; Xu, Zhiguang; Cai, Zengxiao; Guo, Qipeng

    2015-06-28

    Herein, we report the phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs) induced by salt concentration and pH changes. The ionomers are sulfonated polystyrenes (SPSs) with different sulfonation degrees. The emulsion types were determined by conductivity measurements, confocal microscopy and optical microscopy, and the formation of HIPE organogels was verified by the tube-inversion method and rheological measurements. SPSs with high sulfonation degrees (water-soluble) and low sulfonation degrees (water-insoluble) can stabilize oil-in-water emulsions; these emulsions were transformed into water-in-oil HIPEs by varying salt concentrations and/or changing the pH. SPS, with a sulfonation degree of 11.6%, is the most efficient, and as low as 0.2 (w/v)% of the organic phase is enough to stabilize the HIPEs. Phase inversion of the oil-in-water emulsions occurred to form water-in-oil HIPEs by increasing the salt concentration in the aqueous phase. Two phase inversion points from oil-in-water emulsions to water-in-oil HIPEs were observed at pH 1 and 13. Moreover, synergetic effects between the salt concentration and pH changes occurred upon the inversion of the emulsion type. The organic phase can be a variety of organic solvents, including toluene, xylene, chloroform, dichloroethane, dichloromethane and anisole, as well as monomers such as styrene, butyl acrylate, methyl methacrylate and ethylene glycol dimethacrylate. Poly(HIPEs) were successfully prepared by the polymerization of monomers as the continuous phase in the ionomer-stabilized HIPEs.

  4. [Use of perfluorocarbon emulsions for administration of photosensitizing preparations into bone marrow stem cells].

    PubMed

    Temnov, A A; Sklifas, A N; Tereshchenko, A V; Belyĭ, Iu A; Lyskov, N B; Kukushkin, N I

    2010-01-01

    It has been shown that, upon incubation of mouse bone marrow stem cells (BMSC) in vitro with the nanoparticles of perfluorocarbon (PFC) emulsion stabilized by proxanol 268, these nanoparticles penetrate into cells and stay there for a long time (up to 20 days of observation). It has been found that, under in vitro conditions, mouse BMSC loaded with the nanoparticles of both the original emulsion and the emulsion preliminarily incubated with radachlorine do not differ from control stem cells in the rate of division, stretching on a plastic support, and the formation of a monolayer. It has been shown that the exposure to laser radiation of BMSC incubated with the nanoparticles of a PFC emulsion preliminarily incubated with radachlorine under in vitro conditions leads to the death of these cells due to the destruction of the cell membrane. The treatment with laser radiation of BMSC incubated with the nanoparticles of the starting PFC emulsion (without preliminarily incubation with radachlorine) causes no death of these cells. It has been shown in in vivo experiments that, when transplanted to the organism of a recipient mouse, BMSC of a donor mouse incubated with the nanoparticles of a PFC emulsion preliminarily incubated with radachlorine retain their functional activity, in particular the ability to migrate in the animal body. In this case, radachlorine contained in these stem cells retains its major function, to induce the death of stem cells by the action of laser radiation due to the destruction of the cell membrane. The observation period after the transplantation was 5-7 days.

  5. Ordered macroporous materials by emulsion templating

    NASA Astrophysics Data System (ADS)

    Imhof, A.; Pine, D. J.

    1997-10-01

    Ordered macroporous materials with pore diameters comparable to optical wavelengths are predicted to have unique and highly useful optical properties such as photonic bandgaps and optical stop-bands. Tight control over the pore size distribution might also lead to improved macroporous materials (those with pores greater than approximately 50nm) for application as catalytic surfaces and supports, adsorbents, chromatographic materials, filters, light-weight structural materials, and thermal, acoustic and electrical insulators. Although methods exist for producing ordered porous materials with pore diameters less than 10nm (refs 10, 11), there is no general method for producing such materials with uniform pore sizes at larger length scales. Here we report a new method for producing highly monodisperse macroporous materials with pore sizes ranging from 50nm to several micrometres. Starting with an emulsion of equally sized droplets (produced through a repeated fractionation procedure), we form macroporous materials of titania, silica and zirconia by using the emulsion droplets as templates around which material is deposited through a sol-gel process. Subsequent drying and heat treatment yields solid materials with spherical pores left behind by the emulsion droplets. These pores are highly ordered, reflecting the self-assembly of the original monodisperse emulsion droplets into a nearly crystalline array. We show that the pore size can be accurately controlled, and that the technique should be applicable to a wide variety of metal oxides and even organic polymer gels.

  6. Pickering w/o emulsions: drug release and topical delivery.

    PubMed

    Frelichowska, Justyna; Bolzinger, Marie-Alexandrine; Valour, Jean-Pierre; Mouaziz, Hanna; Pelletier, Jocelyne; Chevalier, Yves

    2009-02-23

    The skin absorption from Pickering emulsions as a new dosage form was investigated for the first time. Pickering emulsions are stabilized by adsorbed solid particles instead of emulsifier molecules. They are promising dosage forms that significantly differ from classical emulsions within several features. The skin permeation of a hydrophilic model penetrant (caffeine) was investigated from a w/o Pickering emulsion and compared to a w/o classical emulsion stabilized with an emulsifier. Both emulsions had the same composition and physicochemical properties in order to focus on the effect of the interfacial layer on the drug release and skin absorption processes. The highest permeation rates were obtained from the Pickering emulsion with a pseudo-steady state flux of 25 microg cm(-2)h(-1), threefold higher than from a classical emulsion (9.7 microg cm(-2)h(-1)). After 24h exposure, caffeine was mostly in the receptor fluid and in the dermis; cumulated amounts of caffeine were higher for the Pickering emulsion. Several physicochemical phenomena were investigated for clearing up the mechanisms of enhanced permeation from the Pickering emulsion. Among them, higher adhesion of Pickering emulsion droplets to skin surface was disclosed. The transport of caffeine adsorbed on silica particles was also considered relevant since skin stripping showed that aggregates of silica particles entered deeply the stratum corneum.

  7. Particle-Stabilized Powdered Water-in-Oil Emulsions.

    PubMed

    Binks, Bernard P; Tyowua, Andrew T

    2016-04-05

    The preparation of powdered water-in-oil (w/o) emulsions by gentle aeration of w/o emulsions stabilized by hydrophobic fumed silica particles in the presence of oleophobic fluorinated clay particles is reported for an alkane and a triglyceride oil. The resultant powders consist of water drops dispersed in oil globules themselves dispersed in air (w/o/a). They contain ∼80 wt % of the precursor w/o emulsion and were stable to phase separation for over 1 year but release oil and water when sheared on a substrate. Above a certain ratio of w/o emulsion:fluorinated clay particles, the powdered emulsions partially invert to an emulsion paste, composed of air bubbles and water droplets dispersed in oil. The tap density and angle of repose of the powdered emulsions were measured and compared with those of the corresponding powdered oils making up the continuous phase of the precursor emulsions. The contact angles of water droplets under oil on glass slides spin coated with silica particles and oil drops and w/o emulsion droplets in air on compressed disks of fluorinated clay particles are consistent with the stabilization of w/o emulsions and powdered emulsions, respectively.

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

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2012-09-01

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

  9. The Hybrid Emulsion Detector for MINOS R&D Proposal

    SciTech Connect

    Adamson, P.; Alexandrov, K. V.; Allison, W. W.M.; Alner, G. J.; Ambats, I.; Anderson, B.; Anderson, D. F.; Andreopoulos, C.; Antipov, Yu.; Arroyo, C.; Ayres, D. S.

    1999-04-01

    The MINOS (Main Injector Neutrino Oscillation Search) experiment is designed to search for neutrino oscillations with a sensitivity significantly greater than has been achieved to date. The phenomenon of neutrino oscillations, whose existence has not been proven convincingly so far, allows neutrinos of one "flavor" (type) to slowly transform themselves into another flavor, and then back again to the original flavor, as they propagate through space or matter. The MINOS experiment is optimized to explore the region of neutrino oscillation "parameter space" suggested by previous investigations of atmospheric neutrinos: the Kamiokande, IMB, Super-Kamiokande and Soudan 2 experiments. The study of oscillations in this region with a neutrino beam from the Main Injector requires measurements of the beam after a very long flight path. This in turn requires an intense neutrino beam and a massive detector in order to have an adequate event rate at a great distance from the source. We propose to enhance significantly the physics capabilities of the MINOS experiment by the addition of a Hybrid Emulsion Detector at Soudan, capable of unambigous identification of the neutrino flavor. Recent developments in emulsion experiments make such a detector possible, although significant technological challenges must be overcome. We propose to initiate an R&D effort to identify major potential problems and to develop practical solutions to them. This proposal is meant to be a summary of the work we feel is needed before a credible conceptual design report can be produced. It summarizes both the tasks that need to be done and new incremental resources that are required to perform them. It is our expectation that various individual institutions (those currently in MINOS and others anticipating joining) will submit separate individual funding requests, to funding agencies in both US and abroad, to provide most of the resources listed in Chapter 5. We intend that the present proposal should

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

    PubMed

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

    2013-05-01

    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)=0.615μm compared to D(50)=1.3μm 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.

  11. Synthetic Polymers at Interfaces: Monodisperse Emulsions Multiple Emulsions and Liquid Marbles

    NASA Astrophysics Data System (ADS)

    Sun, Guanqing

    The adsorption of polymeric materials at interfaces is an energetically favorable process which is investigated in much diversified fields, such as emulsions, bubbles, foams, liquid marbles. Pickering emulsion, which is emulsion stabilized by solid particles has been investigated for over one century and preparation of Pickering emulsion with narrow size distribution is crucial for both the theoretical study of the stabilization mechanism and practical application, such as templated fabrication of colloidosomes. The precise control over the size and functionality of polymer latices allows the preparation of monodisperse Pickering emulsions with desired sizes through SPG membrane emulsification at rather rapid rate compared to microfludic production. Double or multiple emulsions have long been investigated but its rapid destabilization has always been a major obstacle in applying them into practical applications. The modern living polymerization techniques allow us to prepare polymers with designed structure of block copolymers which makes it possible to prepare ultra-stable multiple emulsions. The precise tuning of the ratio of hydrophobic part over the hydrophilic can unveil the stabilization mechanism. Liquid marble is a new type of materials of which liquid droplets are coated by dry particles. The coating of an outer layer of dry particles renders the liquid droplets non-sticky at solid surface which is useful in transportation of small amount of liquid without leakage at extreme low friction force. The property of liquid marbles relies largely on the stabilizers and the drying condition of polymeric latices is shown to have great influence on the property of liquid marbles. Firstly, an introduction to the interfacial and colloidal science with special attention to topics on emulsions, multiple emulsion and liquid marbles is given in Chapter 1. The unique features of an interface and a discussion on the definition of colloids are introduced prior to the

  12. Double emulsion solvent evaporation techniques used for drug encapsulation.

    PubMed

    Iqbal, Muhammad; Zafar, Nadiah; Fessi, Hatem; Elaissari, Abdelhamid

    2015-12-30

    Double emulsions are complex systems, also called "emulsions of emulsions", in which the droplets of the dispersed phase contain one or more types of smaller dispersed droplets themselves. Double emulsions have the potential for encapsulation of both hydrophobic as well as hydrophilic drugs, cosmetics, foods and other high value products. Techniques based on double emulsions are commonly used for the encapsulation of hydrophilic molecules, which suffer from low encapsulation efficiency because of rapid drug partitioning into the external aqueous phase when using single emulsions. The main issue when using double emulsions is their production in a well-controlled manner, with homogeneous droplet size by optimizing different process variables. In this review special attention has been paid to the application of double emulsion techniques for the encapsulation of various hydrophilic and hydrophobic anticancer drugs, anti-inflammatory drugs, antibiotic drugs, proteins and amino acids and their applications in theranostics. Moreover, the optimized ratio of the different phases and other process parameters of double emulsions are discussed. Finally, the results published regarding various types of solvents, stabilizers and polymers used for the encapsulation of several active substances via double emulsion processes are reported.

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

    NASA Astrophysics Data System (ADS)

    Aleksandrov, A.; Tioukov, V.

    2013-08-01

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

  14. Double emulsions based on silicone-fluorocarbon-water and their skin penetration.

    PubMed

    Mahrhauser, Denise-Silvia; Fischer, Claudia; Valenta, Claudia

    2016-02-10

    Double emulsions have significant potential in pharmacy and cosmetics due to the feasibility of combining incompatible substances in one product and the protection of sensitive compounds by incorporating them into their innermost phase. However, a major drawback of double emulsions is their thermodynamic instability and their strong tendency to coalesce. In the present study, the physicochemical stability, the skin permeation and the skin penetration potential of modified semi-solid double emulsions was investigated. The double emulsions were prepared of the cosmetically applied perfluoropolyethers Fomblin HC/04 or Fomblin HC-OH, silicone, carbomer and water. Measurement of the droplet size and examination of the microscopic images confirmed their physicochemical stability over the observation period of eight weeks. Franz-type diffusion cell experiments revealed no increase in curcumin permeation due to the employed perfluoropolyethers compared to the respective control formulations. The formulations used as control were O/W macroemulsions with or without a Polysorbate 80/Sorbitane monooleate 80 surfactant combination. Likewise, tape stripping studies showed no penetration enhancing effect of the employed perfluoropolyethers which is desirable as both perfluoropolyethers are commonly applied components in human personal-care products.

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

    PubMed

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

    2011-06-15

    Separation of secondary emulsions of dispersed droplet size less than 10 μm, 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 μm). Experiments were carried out on five different filter media with a wide variation in their pore size (2-51 μm), surface energy (14-46 mN/m) and porosity (0.46-0.87) at similar process conditions. Filter media with different wettability are obtained by applying various hydrophobic and hydrophilic coatings. All the used coatings contain nanoparticles (25 nm) to impart nanoscale surface roughness at the single fiber surface. Besides emulsion properties and operating conditions, the phase separation mechanism and performance highly depends on pore size, surface energy and porosity of the filter media. More complete coalescence takes place at reduced pore size and at a surface preferentially wetted by the dispersed phase. Whereas when the pore size equals to the influent droplet size, then the surface wettability of filter is less effective and the separation mechanism is governed by inflow velocity. The emulsion inflow velocity and pressure drop are significantly affected by the filter media air permeability but do not depend on filter surface energy.

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

    PubMed

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

    2015-07-01

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

  17. Deformation of double emulsions under conditions of flow cytometry hydrodynamic focusing.

    PubMed

    Ma, Shaohua; Huck, Wilhelm T S; Balabani, Stavroula

    2015-11-21

    Water-in-oil-in-water (w/o/w) microfluidics double emulsions offer a new route to compartmentalise reagents into isolated aqueous microenvironments while maintaining an aqueous carrier fluid phase; this enables compatibility with commercial flow cytometry systems such as fluorescence-activated cell sorting (FACS). Double emulsion (inner core) deformation under hydrodynamic focusing conditions that mimic the environment double emulsions experience in flow cytometry applications is of particular importance for droplet stability and cell viability. This paper reports on an experimental study of the dynamic deformation of aqueous cores of w/o/w double emulsions under hydrodynamic focusing, with the sheath flow directed at 45° to the sample flow. A number of factors affecting the inner core deformation and recovery were examined. Deformation was found to depend significantly on the core or shell viscosity, the droplet-to-sheath flow velocity ratio, and core and shell sizes. Core deformation was found to depend more on the type of surfactant rather concentration with high molecular weight surfactant exhibiting a negligible effect on deformation whereas low molecular weight surfactant enhancing deformation at low concentrations due to their lateral mobility at the interface.

  18. DEP actuation of emulsion jets and dispensing of sub-nanoliter emulsion droplets.

    PubMed

    Prakash, Ravi; Kaler, Karan V I S

    2009-10-07

    Liquid Dielectrophoresis (L-DEP) has been successfully leveraged at microscopic scales and shown to provide a controllable means of on-chip precision dispensing and manipulation of sub-nanoliter single emulsion droplets. In this paper, we report on the dynamics of a DEP actuated emulsion jet prior to break-up and compare its characteristic behavior based on the lumped parameter model of Jones et al. (R. Ahmed and T. B. Jones, J. Micromech. Microeng., 2007, 17, 1052). Furthermore, features and aspects of these emulsion jets, their break-up and formation of sub-nanoliter emulsion droplets is studied in further detail. Applications of the proposed scheme in dispensing encapsulated sub-nanoliter droplets is envisioned in various fields including microTAS, on-chip handling and storage of cells and other biological samples for longer duration in controlled environments as well as solving the more general encapsulation issues in surface microfluidic devices. Scalability of the proposed scheme is shown by producing controlled sample-oil single emulsion droplets (aqueous samples in oil) in the range of 50-400 picoliters.

  19. A new scanning system for alpha decay events as calibration sources for range-energy relation in nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Yoshida, J.; Kinbara, S.; Mishina, A.; Nakazawa, K.; Soe, M. K.; Theint, A. M. M.; Tint, K. T.

    2017-03-01

    A new scanning system named "Vertex picker" has been developed to rapid collect alpha decay events, which are calibration sources for the range-energy relation in nuclear emulsion. A computer-controlled optical microscope scans emulsion layers exhaustively, and a high-speed and high-resolution camera takes their micrographs. A dedicated image processing picks out vertex-like shapes. Practical operations of alpha decay search were demonstrated by emulsion sheets of the KEK-PS E373 experiment. Alpha decays of nearly 28 events were detected in eye-check work on a PC monitor per hour. This yield is nearly 20 times more effective than that by the conventional eye-scan method. The speed and quality is acceptable for the coming new experiment, J-PARC E07.

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

    PubMed

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

    2014-07-01

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

  1. Rational use of intravenous fat emulsions.

    PubMed

    Pelham, L D

    1981-02-01

    The composition, effect on blood components, relative value compared with intravenous dextrose, clinical applications as a caloric and fatty acid source, adverse reactions, limitations, and administration of intravenous fat emulsions are reviewed. Fat emulsions provide essential fatty acids and calories and are primarily used to supplement of parenteral nutrition regimens. Their use as a major source of calories remains limited because of cost. However, the trend toward aligning intravenous nutrition to that of the normal diet and the increased demand for peripherally administered parenteral nutrition have increased demand for use. The advantages and disadvantages presented may be used by clinicians to assist in establishing the role of intravenous fat therapy in nutritional support services.

  2. Emulsions Containing Perfluorocarbon Support Cell Cultures

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  3. Refractive index matching and clear emulsions.

    PubMed

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

    2005-01-01

    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.

  4. Imaging techniques applied to characterize bitumen and bituminous emulsions.

    PubMed

    Rodríguez-Valverde, M A; Ramón-Torregrosa, P; Páez-Dueñas, A; Cabrerizo-Vílchez, M A; Hidalgo-Alvarez, R

    2008-01-15

    The purpose of this article is to present some important advances in the imaging techniques currently used in the characterization of bitumen and bituminous emulsions. Bitumen exhibits some properties, such as a black colour and a reflecting surface at rest, which permit the use of optical techniques to study the macroscopic behaviour of asphalt mixes in the cold mix technology based on emulsion use. Imaging techniques allow monitoring in situ the bitumen thermal sensitivity as well as the complex phenomenon of emulsion breaking. Evaporation-driven breaking was evaluated from the shape of evaporating emulsion drops deposited onto non-porous and hydrophobic substrates. To describe the breaking kinetics, top-view images of a drying emulsion drop placed on an aggregate sheet were acquired and processed properly. We can conclude that computer-aided image analysis in road pavement engineering can elucidate the mechanism of breaking and curing of bituminous emulsion.

  5. Evaluation on oxidative stability of walnut beverage emulsions.

    PubMed

    Liu, Shuang; Liu, Fuguo; Xue, Yanhui; Gao, Yanxiang

    2016-07-15

    Walnut beverage emulsions were prepared with walnut kernels, mixed nonionic emulsifiers and xanthan gum. The effects of food antioxidants on the physical stability and lipid oxidation of walnut beverage emulsions were investigated. The results showed that tea polyphenols could not only increase the droplet size of the emulsions, but also enhance physical stability during the thermal storage at 62 ± 1 °C. However, water-dispersed oil-soluble vitamin E and enzymatically modified isoquercitrin obviously decreased the physical stability of the emulsion system during the thermal storage. BHT and natural antioxidant extract had scarcely influenced on the physical stability of walnut beverage emulsions. Tea polyphenols and BHT could significantly retard lipid oxidation in walnut beverage emulsions against thermal and UV light exposure during the storage. Vitamin E exhibited the prooxidant effect during the thermal storage and the antioxidant attribute during UV light exposure. Other food antioxidants had no significant effect on retarding lipid oxidation during thermal or light storage.

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

    Nuclear emulsions are an effective choice in many scenarios of volcano radiography by cosmic-ray muons. They are cheap and emulsion-based detectors require no on-site power supply. Nuclear emulsion films provide sub-micrometric tracking precision and intrinsic angular accuracy better than 1 mrad. Imaging the inner structure of a volcano requires that the cosmic-ray absorption map be measured on wide angular range. High-absorption directions can be probed by allowing for large statistics, which implies a large overall flux, i.e. wide surface for the detector. A total area of the order of a few m2 is nowadays typical, thanks to the automatic readout tools originally developed for high-energy physics experiments such as CHORUS, PEANUT, OPERA. The European Scanning System is now being used to read out nuclear emulsion films exposed to cosmic rays on the side of volcanoes. The structure of the system is described in detail with respect to both hardware and software. Its present scanning speed of 20 cm2/h/side/microscope is suitable to fulfil the needs of the current exposures of nuclear emulsion films for muon radiograph, but it is worth to notice that applications in volcano imaging are among the driving forces pushing to increase the performances of the system. Preliminary results for the Unzen volcano of a joint effort by research groups in Italy and Japan show that the current system is already able to provide signal/background ratio in the range 100÷10000:1, depending on the quality cuts set in the off-line data analysis. The size of the smallest detectable structures in that experimental setup is constrained by the available statistics in the region of highest absorption to about 50 mrad, or 22 m under the top of the mountain. Another exposure is currently taking data at the Stromboli volcano. Readout of the exposed films is expected to begin in March 2012, and preliminary results will be available soon after. An effort by several universities and INFN has

  7. [Multiple emulsions; bioactive compounds and functional foods].

    PubMed

    Jiménez-Colmenero, Francisco

    2013-01-01

    The continued appearance of scientific evidence about the role of diet and/or its components in health and wellness, has favored the emergence of functional foods which currently constitute one of the chief factors driving the development of new products. The application of multiple emulsions opens new possibilities in the design and development of functional foods. Multiple emulsions can be used as an intermediate product (food ingredient) into technological strategies normally used in the optimization of the presence of bioactive compounds in healthy and functional foods. This paper presents a summary of the types, characteristics and formation of multiple emulsions, possible location of bioactive compounds and their potential application in the design and preparation of healthy and functional foods. Such applications are manifested particularly relevant in relation to quantitative and qualitative aspects of lipid material (reduced fat/calories and optimization of fatty acid profile), encapsulation of bioactive compounds mainly hydrophilic and sodium reduction. This strategy offers interesting possibilities regarding masking flavours and improving sensory characteristics of foods.

  8. Lipid Emulsion for Local Anesthetic Systemic Toxicity

    PubMed Central

    Ciechanowicz, Sarah; Patil, Vinod

    2012-01-01

    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

  9. Semiphysical development of holograms recorded in silver halide emulsions

    NASA Astrophysics Data System (ADS)

    Banyasz, Istvan; Belendez, Augusto; Pascual, Inmaculada V.; Fimia, Antonio

    2000-10-01

    In the course of experiments on measurement of the effects of processing on nonlinear characteristics of silver halide holograms recorded in Agfa-gevaert 8E75HD emulsions we found that, under certain circumstances, the AAC developer acted as a semi-physical developer instead of the normal chemical developing action. The developed and fixed holograms were of low optical density (<0.5) and of high diffraction efficiency (up to 15%). Phase contrast microscopy revealed that very clean phase gratings were obtained. This effect of the AAC developer was due to the replacement of one of its components, sodium carbonate of purest grade with that of for analysis grade of the same company.

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

    PubMed Central

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

    2014-01-01

    Home parenteral nutrition (PN) is associated with many complications including severe hepatobiliary dysfunction. Commercial ω-6 fatty acid-soybean based-lipid emulsions in PN may mediate long term PN associate liver disease (PNALD) whereas ω-3-fish oil parenteral emulsions have shown to reverse PNALD in children. However, its clinical effectiveness in adults has been scarcely reported. In this work, we study the role of soybean and fish oil lipid commercial emulsions on inflammatory and profibrotic liver markers in adults with long term PNALD and in in vitro cellular models. Inflammatory and profibrotic markers were measured in serum of ten adults with long term PNALD and in culture supernatants of monocytes. Liver epithelial to mesenchymal transition (EMT) was induced by transforming growth factor beta 1 (TGFβ1) to evaluate in vitro liver fibrosis. Omegaven®, a 100% fish oil commercial emulsion, was infused during four months in two patients with severe long term PNALD reversing, at the first month, the inflammatory, profibrotic and clinical parameters of PNALD. The effect was maintained during the treatment course but impaired when conventional lipid emulsions were reintroduced. The other patients under chronic soybean oil-based PN showed elevated inflammatory and profibrotic parameters. In vitro human monocytes stimulated with lipopolysaccharide induced a strong inflammatory response that was suppressed by Omegaven®, but increased by soybean emulsions. In other experiments, TGFβ1 induced EMT that was suppressed by Omegaven® and enhanced by soybean oil lipid emulsions. Omegaven® improves clinical, anti-inflammatory and anti-fibrotic parameters in adults with long-term home PNALD. PMID:25502575

  11. Field testing of asphalt-emulsion radon-barrier system

    SciTech Connect

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

    1981-09-01

    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.

  12. Development of Nuclear Emulsion for Fast Neutron Measurement

    NASA Astrophysics Data System (ADS)

    Machii, Shogo; Kuwabara, Kenichi; Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. Energy resolution of nuclear emulsion is 21% (12%) FWHM against neutron energy of 2.8 MeV (4.9 MeV). Nuclear emulsion has high gamma ray rejection power. For now, at least 2×104 gamma rays/cm2, no increase of as a background for neutron measurement when scan using automatic nuclear emulsion read out system HTS. This value suggests that it is applicable even under high gamma ray environment, such as nuclear fusion reactor.

  13. Interaction between a perfluorocarbon emulsion and radiographic contrast media.

    PubMed

    Franke, Ralf-Peter; Reuter, Peter; Röhlke, Wolfgang; Matschke, Klaus; Keller, Steffi; Klosterhalfen, Bernd; Mittermayer, Christian; Mrowietz, Christoph; Jung, Friedrich

    2004-03-01

    This study evaluated specially designed perfluorocarbon (PFC) emulsions as blood substitutes in case of induced ischemia of the left heart ventricle in healthy farm pigs. Two hundred ml of perfluorocarbon emulsion were infused while 200 ml of blood were simultaneously drawn. Radiographic contrast media were given to aid placement of balloon catheters in the left coronary artery. Histopathological analysis showed that right heart failure caused the deaths of both pigs. Particles (up to>3 micro) of foreign body materials obstructed capillaries of all organs analyzed (heart, lung, liver, kidneys and spleen). Laboratory investigation showed severe interference between the PFC emulsion and radiographic contrast media, resulting in the deterioration of the PFC emulsion. The strongest interference occurred when PFC emulsion and Accupaque interacted; particle size started at an initial 311 nm and went up to >3 micro within seconds. Great care must be taken when PFC emulsions are used in combination with x-ray contrast media. None of the described radiographic contrast media should be used within 48 hours prior to the use of this PFC emulsion. Also, the use of these contrast media should be avoided for a certain period of time after using PFC emulsion. The mechanisms of elimination of PFC emulsions from the circulation are not completely understood and has yet to be evaluated.

  14. Photonic band gap effect and structural color from silver nanoparticle gelatin emulsion.

    PubMed

    Kok, Mang Hin; Ma, Rui; Lee, Jeffrey Chi Wai; Tam, Wing Yim; Chan, C T; Sheng, Ping; Cheah, Kok Wai

    2005-10-01

    We have fabricated planar structures of silver nanoparticles in monochromatic gelatin emulsion with a continuous spacing ranging from 0.15-0.40 micron using a two-beam interference of a single laser source. Our planar holograms display a colorful "rainbow" pattern and photonic bandgaps covering the visible and IR ranges. We model the planar silver nanoparticle-gelatin composite system using an effective medium approach and good agreement is obtained between theory and experiment.

  15. Experimental Study of Sound Attenuation in Quasi-Monodisperse Emulsions

    NASA Astrophysics Data System (ADS)

    Herrmann, N.; Boltenhagen, P.; Lemaréchal, P.

    1996-10-01

    Very narrow size distribution oil-in-water emulsions have been prepared by using a recently proposed selective creaming method. The emulsions have been characterized by static and dynamic light scattering measurements. The ultrasonic absorption of the emulsions has been measured with an acoustic interferometer at frequencies between 0.5 and 10 MHz for a wide range of concentrations and droplets sizes. The comparison of the experimental results with existing theories shows an excellent agreement at oil volume fractions up to 0.15. The discrepancy between theory and experiments observed at higher volume fractions is attributed to thermal interactions between droplets for which a semi-quantitative model is proposed. Des émulsions d'huiles dans l'eau présentant une distribution en taille très étroite ont été préparées grâce à une méthode récemment proposée, fondée sur le crémage sélectif des goutelettes. Ces émulsions ont été caractérisées par diffusion statique et dynamique de la lumière. L'absorption ultrasonore des émulsions a été mesurée à l'aide d'un interféromètre acoustique à des fréquences comprises entre 0,5 et 10 MHz pour une large gamme de concentrations et de dimensions des gouttelettes. L'accord des résultats expérimentaux avec les théories existantes est excellent pour les fractions volumiques en huile inférieures à 15 %. L'écart entre théorie et expérience qui apparaît aux fractions volumiques plus élvées est attribué aux interactions thermiques entre gouttelettes, pour lesquelles un modèle semi-quantitatif est proposé.

  16. Synthesis and Characterization of Waterborne Fluoropolymers Prepared by the One-Step Semi-Continuous Emulsion Polymerization of Chlorotrifluoroethylene, Vinyl Acetate, Butyl Acrylate, Veova 10 and Acrylic Acid.

    PubMed

    Liu, Hongzhu; Bian, Jiming; Wang, Zhonggang; Hou, Chuan-Jin

    2017-01-22

    Waterborne fluoropolymer emulsions were synthesized using the one-step semi-continuous seed emulsion polymerization of chlorotrifluoroethylene (CTFE), vinyl acetate (VAc), n-butyl acrylate (BA), Veova 10, and acrylic acid (AA). The main physical parameters of the polymer emulsions were tested and analyzed. Characteristics of the polymer films such as thermal stability, glass transition temperature, film-forming properties, and IR spectrum were studied. Meanwhile, the weatherability of fluoride coatings formulated by the waterborne fluoropolymer and other coatings were evaluated by the quick ultraviolet (QUV) accelerated weathering test, and the results showed that the fluoropolymer with more than 12% fluoride content possessed outstanding weather resistance. Moreover, scale-up and industrial-scale experiments of waterborne fluoropolymer emulsions were also performed and investigated.

  17. The Gibbs-Thomson effect and intergranular melting in ice emulsions: Interpreting the anomalous heat capacity and volume of supercooled water

    NASA Astrophysics Data System (ADS)

    Johari, G. P.

    1997-12-01

    Calculations for the Gibbs-Thomson effect and the intergranular melting of the ice droplets in (water) emulsions at temperatures below 273.16 K show that water and ice coexist at thermodynamic equilibrium in an apparently frozen emulsion. The fraction of water at this equilibrium increases on heating, which alters further the thermodynamic properties of the emulsion. As some of the ice in the emulsion has already melted, the increase in the enthalpy, H, and heat capacity, Cp, and the decrease in the volume measured on the normal melting at 273.16 K, are less than the values anticipated. The ratio of this increase in H, or Cp, on melting of the emulsion to the corresponding value for pure ice, underestimates the emulsion's water content which, when used for scaling the difference between the Cp of the unfrozen and frozen emulsion at lower temperatures, as in earlier studies, leads to a larger Cp of supercooled water than the actual value. Similar scaling of the corresponding difference between the volume leads to higher volume, or lower density, than the actual value. A formalism for this premelting effect is given for both the adiabatic and differential scanning calorimetry (DSC), and its magnitude is calculated. New experiments show that the rise in the DSC signal, or equivalently in the apparent Cp observed on heating the frozen emulsion, occurs over a temperature range much wider than the Gibbs-Thomson effect and intergranular melting predict, for which reasons are given. It is shown that Cp of the dispersant phase is also affected by the melting of ice droplets. There are four consequences of the premelting effects for all finely dispersed materials, for frozen water emulsions below 273.16 K: (i) water and ice coexist in the emulsion, (ii) its apparent Cp will increase with increase in the heat input used to measure it, (iii) the apparent Cp will increase with decrease in the average size of the droplets, and (iv) the apparent Cp will decrease on annealing the

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  19. Perfluorochemical emulsions decrease Kupffer cell phagocytosis

    SciTech Connect

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

    1991-07-01

    One drawback to using perfluorochemical emulsions as blood substitutes is that perfluorochemical particles are cleared from the blood by the reticuloendothelial system, primarily liver and spleen. 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.

  20. Water-in-silicone oil emulsion stabilizing surfactants formed from native albumin and alpha,omega-triethoxysilylpropyl-polydimethylsiloxane.

    PubMed

    Zelisko, Paul M; Flora, Kulwinder K; Brennan, John D; Brook, Michael A

    2008-08-01

    Contact with hydrophobic silicones frequently leads to protein denaturation. However, it is demonstrated that albumin in water-in-silicone oil emulsions retains its native structure in the presence of a functional, triethoxysilyl-terminated silicone polymer, TES-PDMS. Both HSA and TES-PDMS were essential for the formation of stable water-in-silicone oil emulsions: attempts to generate stable emulsions using independently either the protein or the functionalized silicone as a surfactant failed. Confocal microscopy indicated that the human serum albumin (HSA) preferentially adsorbed at the oil/water interface, even in the presence of another protein (glucose oxidase). A variety of experiments demonstrated that the hydrolysis of the Si-OEt groups on the functional silicone occurred only to a limited extent, consistent with the absence of a covalent linkage between the silicone and protein, or of cross-linked silicones at the interface. The fluorescence spectra of HSA extracted from the emulsions, front-faced fluorescence experiments on the HSA/silicone emulsion itself, and HSA/salicylate binding studies all demonstrated that the stability of the water/oil interface decreased as the protein began to unfold: unfolding of the protein in the emulsion was slower than in aqueous solution. The experimental evidence indicated that the interaction between HSA and TES-PDMS is not associated with either homomolecular (HSA/HSA; TES-PDMS/TES-PDMS) interactions or with covalent linkage between two the polymers. Rather, the data is consistent with the direct binding of unhydrolyzed Si(OEt) 3 groups to native HSA. The nature of these interactions is discussed.

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

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

  2. Rheological properties of heavy oils and heavy oil emulsions

    SciTech Connect

    Khan, M.R.

    1996-06-01

    In this study, the author investigated the effects of a number of process variables such as shear rate, measurement temperature, pressure, the influence of pretreatment, and the role of various amounts of added water on the rheology of the resulting heavy oil or the emulsion. Rheological properties of heavy oils and the corresponding emulsions are important from transportation and processing standpoints.

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

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

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

  4. Mannans as stabilizers of oil-in-water beverage emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant polysaccharides and gums such as gum arabic (GA) are commonly used as stabilizers of oil-in-water emulsions. O-acetyl-galactoglucomannan (GGM), a by-product from mechanical pulping of spruce wood, is able to stabilize colloidal wood resin emulsions (Hannuksela and Holmbom, 2004), but its use a...

  5. Nanoscale and Microscale Iron Emulsions for Treating DNAPL

    NASA Technical Reports Server (NTRS)

    Geiger, Cherie L.

    2002-01-01

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

  6. 21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524... ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications. Each milliliter contains 5 milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor. See No. 000859 in §...

  7. 21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524... ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications. Each milliliter contains 5 milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor. See No. 000859 in §...

  8. 21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524... ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications. Each milliliter contains 5 milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor. See No. 000859 in §...

  9. 21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524... ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications. Each milliliter contains 5 milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor. See No. 000859 in §...

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

    PubMed

    McClements, David Julian

    2010-01-01

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

  11. Synthesis of metallic nanoshells on porphyrin-stabilized emulsions

    DOEpatents

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

    2011-12-13

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

  12. Formulation of indomethacin emulsion using biopolymer of Prunus avium.

    PubMed

    Verma, Shivangi; Dabral, Prashant; Rana, Vinod; Upadhaya, Kumud; Bhardwaj

    2012-03-01

    The aim of the investigation was to formulate Indomethacin Emulsion using Bio-polymer as Emulsifier. Different batches of emulsions were prepared by varying concentration of biopolymer prunus avium. Based evaluation of the prepared polymers, a conclusion can be drawn that in the Prunus avium bio-material can serve as a promising film forming agent for formulating various drug.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  14. Review of Intravenous Lipid Emulsion Therapy

    PubMed Central

    2016-01-01

    Intravenous fat emulsion (IVFE) is an important source of calories and essential fatty acids for patients receiving parenteral nutrition (PN). Administered as an individual infusion or combined with PN, the fats provided by IVFE are vital for cellular structural function and metabolism. The affinity of some medications to lipids has led to the use of IVFE as a treatment for any lipophilic drug overdose. This article will explain the available formulations of IVFE, administration, and maintenance issues, as well as the risks and benefits for various applications. PMID:27828934

  15. Detoxifying emulsion for overdosed aspirin intoxication.

    PubMed

    Zhang, Wenjun; Stambouli, Moncef; Pareau, Dominique

    2013-01-30

    Aspirin overdose could lead to intoxication, with the clinical manifestations of vomit, pulmonary edema and severe dyspnea. Stomach washing, emetics and activated charcoal are the common treatments with a limited efficiency for the intoxication. In this study, an active emulsion for aspirin intoxication was prepared with the detoxifying efficiency of 100% in less than 15 min, with the conditions of dodecane used as the oil phase, 8% Abil EM90 as the surfactant and 0.1 mol/L sodium hydroxide as the inner aqueous phase in a volume ratio of 2 between internal aqueous phase and the oil phase.

  16. An exclusively based parenteral fish-oil emulsion reverses cholestasis.

    PubMed

    Triana Junco, Miryam; García Vázquez, Natalia; Zozaya, Carlos; Ybarra Zabala, Marta; Abrams, Steven; García de Lorenzo, Abelardo; Sáenz de Pipaón Marcos, Miguel

    2014-10-25

    Prolonged parenteral nutrition (PN) leads to liver damage. Recent interest has focused on the lipid component of PN. A lipid emulsion based on w-3 fatty acids decrease conjugated bilirubin. A mixed lipid emulsion derived from soybean, coconut, olive, and fish oils reverses jaundice. Here we report the reversal of cholestasis and the improvement of enteral feeding tolerance in 1 infant with intestinal failure-associated liver disease. Treatment involved the substitution of a mixed lipid emulsion with one containing primarily omega-3 fatty acids during 37 days. Growth and biochemical tests of liver function improved significantly. This suggests that fat emulsions made from fish oils may be more effective means of treating this condition compared with an intravenous lipid emulsion containing soybean oil, medium -chain triglycerides, olive oil, and fish oil.

  17. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Frijters, Stefan; Günther, Florian; Harting, Jens

    2014-10-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2010-03-01

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

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

    PubMed

    Berton-Carabin, Claire C; Schroën, Karin

    2015-01-01

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

  1. Scaling properties of fractional momentum loss of high- pT hadrons in nucleus-nucleus collisions at sNN from 62.4 GeV to 2.76 TeV

    SciTech Connect

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Alexander, J.; Alfred, M.; Al-Ta'ani, H.; Angerami, A.; Aoki, K.; Apadula, N.; Aphecetche, L.; Aramaki, Y.; Armendariz, R.; Aronson, S. H.; Asai, J.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Baldisseri, A.; Bandara, N. S.; Bannier, B.; Barish, K. N.; Barnes, P. D.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Batsouli, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Beaumier, M.; Beckman, S.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Blau, D. S.; Boissevain, J. G.; Bok, J. S.; Borel, H.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Castera, P.; Chang, B. S.; Charvet, J. -L.; Chen, C. -H.; Chernichenko, S.; Chi, C. Y.; Chiba, J.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Churyn, A.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cleven, C. R.; Cole, B. A.; Comets, M. P.; Connors, M.; Constantin, P.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Danley, T. W.; Das, K.; Datta, A.; Daugherity, M. S.; David, G.; Deaton, M. B.; DeBlasio, K.; Dehmelt, K.; Delagrange, H.; Denisov, A.; d'Enterria, D.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Ding, L.; Dion, A.; Diss, P. B.; Do, J. H.; Donadelli, M.; D'Orazio, L.; Drapier, O.; Drees, A.; Drees, K. A.; Dubey, A. K.; Durham, J. M.; Durum, A.; Dutta, D.; Dzhordzhadze, V.; Edwards, S.; Efremenko, Y. V.; Egdemir, J.; Ellinghaus, F.; Emam, W. S.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Feege, N.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gadrat, S.; Gainey, K.; Gal, C.; Gallus, P.; Garg, P.; Garishvili, A.; Garishvili, I.; Ge, H.; Giordano, F.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Gosset, J.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gunji, T.; Guo, L.; Gustafsson, H. -Å.; Hachiya, T.; Hadj Henni, A.; Haegemann, C.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Hamilton, H. F.; Han, R.; Han, S. Y.; Hanks, J.; Harada, H.; Hartouni, E. P.; Haruna, K.; Hasegawa, S.; Haseler, T. O. S.; Hashimoto, K.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hiejima, H.; Hill, J. C.; Hobbs, R.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Hoshino, T.; Hotvedt, N.; Huang, J.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ide, J.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imrek, J.; Inaba, M.; Inoue, Y.; Iordanova, A.; Isenhower, D.; Isenhower, L.; Ishihara, M.; Isobe, T.; Issah, M.; Isupov, A.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jezghani, M.; Jia, J.; Jiang, X.; Jin, J.; Jinnouchi, O.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kanda, S.; Kaneta, M.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kanou, H.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Key, J. A.; Khachatryan, V.; Khanzadeev, A.; Kijima, K. M.; Kikuchi, J.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.; Kim, E. -J.; Kim, G. W.; Kim, H. J.; Kim, K. -B.; Kim, M.; Kim, S. H.; Kim, Y. -J.; Kim, Y. K.; Kimelman, B.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Kitamura, R.; Kiyomichi, A.; Klatsky, J.; Klay, J.; Klein-Boesing, C.; Kleinjan, D.; Kline, P.; Koblesky, T.; Kochenda, L.; Kochetkov, V.; Komatsu, Y.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kotov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Krizek, F.; Kubart, J.; Kunde, G. J.; Kurihara, N.; Kurita, K.; Kurosawa, M.; Kweon, M. J.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, B.; Lee, D. M.; Lee, J.; Lee, K.; Lee, K. B.; Lee, K. S.; Lee, M. K.; Lee, S.; Lee, S. H.; Lee, S. R.; Lee, T.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Leitner, E.; Lenzi, B.; Lewis, B.; Li, X.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Love, B.; Luechtenborg, R.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Malakhov, A.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Mašek, L.; Masui, H.; Masumoto, S.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Miller, T. E.; Milov, A.; Mioduszewski, S.; Mishra, D. K.; Mishra, M.; Mitchell, J. T.; Mitrovski, M.; Miyachi, Y.; Miyasaka, S.; Mizuno, S.; Mohanty, A. K.; Mohapatra, S.; Montuenga, P.; Moon, H. J.; Moon, T.; Morino, Y.; Morreale, A.; Morrison, D. P.; Motschwiller, S.; Moukhanova, T. V.; Mukhopadhyay, D.; Murakami, T.; Murata, J.; Mwai, A.; Nagae, T.; Nagamiya, S.; Nagashima, K.; Nagata, Y.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakagomi, H.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Nederlof, A.; Netrakanti, P. K.; Newby, J.; Nguyen, M.; Nihashi, M.; Niida, T.; Nishimura, S.; Norman, B. E.; Nouicer, R.; Novák, T.; Novitzky, N.; Nyanin, A. S.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Ohnishi, H.; Oka, M.; Okada, K.; Omiwade, O. O.; Onuki, Y.; Orjuela Koop, J. D.; Osborn, J. D.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pal, D.; Palounek, A. P. T.; Pantuev, V.; Papavassiliou, V.; Park, B. H.; Park, I. H.; Park, J.; Park, J. S.; Park, S.; Park, S. K.; Park, W. J.; Pate, S. F.; Patel, L.; Patel, M.; Pei, H.; Peng, J. -C.; Pereira, H.; Perepelitsa, D. V.; Perera, G. D. N.; Peresedov, V.; Peressounko, D. Yu.; Perry, J.; Petti, R.; Pinkenburg, C.; Pinson, R.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Purwar, A. K.; Qu, H.; Rak, J.; Rakotozafindrabe, A.; Ramson, B. J.; Ravinovich, I.; Read, K. F.; Rembeczki, S.; Reuter, M.; Reygers, K.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Rinn, T.; Roach, D.; Roche, G.; Rolnick, S. D.; Romana, A.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Rosnet, P.; Rowan, Z.; Rubin, J. G.; Rukoyatkin, P.; Ružička, P.; Rykov, V. L.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakai, S.; Sakashita, K.; Sakata, H.; Sako, H.; Samsonov, V.; Sano, M.; Sano, S.; Sarsour, M.; Sato, S.; Sato, T.; Sawada, S.; Schaefer, B.; Schmoll, B. K.; Sedgwick, K.; Seele, J.; Seidl, R.; Semenov, A. Yu.; Semenov, V.; Sen, A.; Seto, R.; Sett, P.; Sexton, A.; Sharma, D.; Shein, I.; Shevel, A.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Skutnik, S.; Slunečka, M.; Snowball, M.; Soldatov, A.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Sparks, N. A.; Staley, F.; Stankus, P. W.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Sugitate, T.; Suire, C.; Sukhanov, A.; Sumita, T.; Sun, J.; Sziklai, J.; Tabaru, T.; Takagi, S.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tarján, P.; Tennant, E.; Themann, H.; Thomas, T. L.; Tieulent, R.; Timilsina, A.; Todoroki, T.; Togawa, M.; Toia, A.; Tojo, J.; Tomášek, L.; Tomášek, M.; Torii, H.; Towell, C. L.; Towell, R.; Towell, R. S.; Tram, V-N.; Tserruya, I.; Tsuchimoto, Y.; Tsuji, T.; Vale, C.; Valle, H.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Vinogradov, A. A.; Virius, M.; Vossen, A.; Vrba, V.; Vznuzdaev, E.; Wagner, M.; Walker, D.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Wei, R.; Wessels, J.; White, A. S.; White, S. N.; Winter, D.; Wolin, S.; Wood, J. P.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Xia, B.; Xie, W.; Xue, L.; Yalcin, S.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Yasin, Z.; Ying, J.; Yokkaichi, S.; Yoo, J. H.; Yoon, I.; You, Z.; Young, G. R.; Younus, I.; Yu, H.; Yushmanov, I. E.; Zajc, W. A.; Zaudtke, O.; Zelenski, A.; Zhang, C.; Zhou, S.; Zimamyi, J.; Zolin, L.; Zou, L.

    2016-02-22

    We present measurements of the fractional momentum loss (Sloss = delta pT / pT) of high-transverse-momentum-identified hadrons in heavy-ion collisions. Using pi0 in Au + Au and Cu + Cu collisions at √sNN = 62.4 and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb + Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of Sloss as a function of a number of variables: the number of participants, Npart, the number of quark participants, Nqp, the charged-particle density, dNch/dη, and the Bjorken energy density times the equilibration time, epsilonBjτ0. We also find that the pT, where Sloss has its maximum, varies both with centrality and collision energy. Above the maximum, Sloss tends to follow a power-law function with all four scaling variables. Finally, the data at √sNN = 200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of Sloss with dNch/dη and εBjτ0, lending insight into the physics of parton energy loss.

  2. Synthesis of mesoporous poly(melamine-formaldehyde) particles by inverse emulsion polymerization.

    PubMed

    Schwarz, Dana; Weber, Jens

    2017-07-15

    Mesoporous poly(melamine-formaldehyde) (MF) particles with surface areas of up to 200m(2)g(-1) were synthesized by an inverse emulsion polymerization using dodecane and Span80® as continuous phase. The finer details of the shape control (using emulsion techniques) and the porosity control (using silica nanoparticles as hard-template) are discussed. The impact of phase-separation processes on the observable porosity of the 20-200µm sized spherical particles is analysed by gas sorption methods and electron microscopy. The high density of amine and triazine functional groups in the porous MF particles make the material a promising adsorber for heavy metal ions and methylene blue. In a preliminary column experiment, the synthesized material exhibited a total capacity of 2.54mmol/g (≙ 812.4mg/g) for the adsorption of methylene blue.

  3. Evidence for Marginal Stability in Emulsions

    NASA Astrophysics Data System (ADS)

    Lin, Jie; Jorjadze, Ivane; Pontani, Lea-Laetitia; Wyart, Matthieu; Brujic, Jasna

    2016-11-01

    We report the first measurements of the effect of pressure on vibrational modes in emulsions, which serve as a model for soft frictionless spheres at zero temperature. As a function of the applied pressure, we find that the density of states D (ω ) exhibits a low-frequency cutoff ω*, which scales linearly with the number of extra contacts per particle δ z . Moreover, for ω <ω*, our results are consistent with D (ω )˜ω2/ω*2, a quadratic behavior whose prefactor is larger than what is expected from Debye theory. This surprising result agrees with recent theoretical findings [E. DeGiuli, A. Laversanne-Finot, G. A. Düring, E. Lerner, and M. Wyart, Soft Matter 10, 5628 (2014); S. Franz, G. Parisi, P. Urbani, and F. Zamponi, Proc. Natl. Acad. Sci. U.S.A. 112, 14539 (2015)]. Finally, the degree of localization of the softest low frequency modes increases with compression, as shown by the participation ratio as well as their spatial configurations. Overall, our observations show that emulsions are marginally stable and display non-plane-wave modes up to vanishing frequencies.

  4. ESR studies of semicontinuous emulsion polymerization

    SciTech Connect

    Lau, W.; Westmoreland, D.G.

    1993-12-31

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

  5. Stability of drug-carrier emulsions containing phosphatidylcholine mixtures.

    PubMed

    Trotta, Michele; Pattarino, Franco; Ignoni, Terenzio

    2002-03-01

    Lipid emulsion particles containing 10% of medium chain triglycerides were prepared using 2% w/w of a mixture 1:1 w/w of purified soya phosphatidylcholine and 2-hexanoyl phosphatidylcholine as emulsifier mixture, for use as drug carriers. The mean droplet sizes of emulsions, prepared using an Ultra Turrax or a high-pressure homogenizer, were about 288 and 158 nm, respectively, compared with 380 and 268 nm for emulsions containing lecithin, or 325 and 240 nm for those containing 6-phosphatidylcholine. The stability of the emulsions, determined by monitoring the decrease of a lipophilic marker at a specified level within the emulsion, and observing coalescence over time, was also greatly increased using the emulsifier mixture. The emulsion stability did not notably change in the presence of a model destabilizing drug, indomethacin. The use of a second hydrophilic surfactant to adjust the packing properties of the lecithin at the oil-water interface provided an increase in the stability of lipid emulsions, and this may be of importance in the formulation of drug delivery systems.

  6. Data on the physical characterization of oil in water emulsions.

    PubMed

    Zalazar, Aldana L; Gliemmo, María F; Campos, Carmen A

    2016-12-01

    This article contains experimental data and images for the physical characterization of oil in water emulsions. Mentioned data are related to the research article "Effect of stabilizers, oil level and structure on the growth of Zygosaccharomyces bailii and on physical stability of model systems simulating acid sauces" (A.L. Zalazar, M.F. Gliemmo, C.A. Campos, 2016) [1]. Physical characterization of emulsions was performed through the evaluation of Span and Specific Surface Area (SSA) determined by light scattering using a Mastersizer. Furthermore, microscopy images were recorded by confocal scanning laser microscopy (CSLM). The latter are presented to collaborate in the analysis of emulsion microstructure.

  7. On mini-cluster observed by Chacaltaya emulsion chamber experiment

    NASA Technical Reports Server (NTRS)

    Tati, T.

    1985-01-01

    Bundles of electromagnetic showers with very small tranverse momenta (approx. 10 MeV) accompanied by decay products of Chiron-type fireballs, have been observed. These bundles are called Miniclusters. This phenomenon supports the picture of fireballs made up of hadronic matter and based on the theory of the finite degree of freedom.

  8. Polyacrylamide-Polydivinylbenzene Decorated Membrane for Sundry Ionic Stabilized Emulsions Separation via a Facile Solvothermal Method.

    PubMed

    Zhang, Weifeng; Liu, Na; Cao, Yingze; Chen, Yuning; Zhang, Qingdong; Lin, Xin; Qu, Ruixiang; Li, Haifang; Feng, Lin

    2016-08-24

    Aiming to solve the worldwide challenge of stabilized oil-in-water emulsion separation, a PAM-PDVB decorated nylon membrane is fabricated via a facile solvothermal route in our group. The main composition is PAM, while the PDVB plays a role as cross-linker in order to improve the interaction between the polymer and the substrate. By the combination of the superhydrophilic and underwater superoleophobic wettability of the PAM polymer with the micropore size of the substrate, the as-prepared material is able to achieve the separation of various stabilized oil-in-water emulsions including cationic type, nonionic type, and anionic type. Compared with previous works, the emulsions used in this case are more stable and can stay for several days. Besides, the solvothermal method is facile, cost saving, and relatively environmentally friendly in this experiment. Moreover, the PAM-PDVB modified membrane exhibits excellent pH stability, recyclability, and high separation efficiency (above 99%), which can be scaled up and used in the practical industrial field.

  9. A new generation scanning system for the high-speed analysis of nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Galati, G.; Lauria, A.; Montesi, M. C.; Tioukov, V.; Vladymyrov, M.

    2016-06-01

    The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting nuclear emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of nuclear emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.

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

    PubMed

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

    2010-01-01

    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.

  11. Oxytocin gene deletion mice overconsume palatable sucrose solution but not palatable lipid emulsions.

    PubMed

    Miedlar, J A; Rinaman, L; Vollmer, R R; Amico, J A

    2007-09-01

    We previously reported that oxytocin knockout (OT KO) mice display markedly enhanced intake of sweet and nonsweet carbohydrate solutions compared with intake by wild-type (WT) mice of the same background strain. The present study was conducted to determine whether OT KO mice demonstrate enhanced intake of Intralipid, a palatable lipid emulsion. Male or female mice of both genotypes that were naive to the test solution were given continuous two-bottle access to Intralipid and water with food available ad libitum for 3 days. Throughout the experiment, mice of both genotypes showed a marked preference for Intralipid over water. On the 1st day, OT KO mice displayed twofold greater preference and consumed nearly twice as much Intralipid compared with WT cohorts. However, on subsequent days of exposure, Intralipid preference and intake did not differ between genotypes over a range of lipid concentrations presented in descending or ascending order. Daily and hourly measures of lipid vs. sucrose intake confirmed that OT KO mice consumed more sucrose solution, but not lipid emulsion, than WT mice. During ad libitum access to Intralipid, both genotypes consumed significantly more calories from the emulsion as concentration increased. Both genotypes maintained consistent total daily caloric intake (lipid plus chow) and compensated by decreasing chow intake over the course of the study. These findings, coupled with prior reports from our laboratory, support the view that OT signaling pathways participate in limiting intake of palatable carbohydrate-containing solutions, but do not appear to play a role in limiting intake of Intralipid.

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

    PubMed

    Panpanit, S; Visvanathan, C; Muttamara, S

    2002-03-01

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

  13. Cationic acrylamide emulsion polymer brine thickeners

    SciTech Connect

    Gleason, P.A.; Piccoline, M.A.

    1986-12-02

    This patent describes a thickened, solids free, aqueous drilling and servicing brine having a density of at least 14.4 ppg. comprising (a) an aqueous solution of at least one water-soluble salt of a multivalent metal, and (b) a cationic water-in-oil emulsion polymer of acrylamide or methacrylamide and a cationic monomer selected from the group consisting of a dialkylaminoalkyl acrylamide or methacrylamide, a trialkylaminoalkyl acrylamide or methacrylamide, a trialkylaminoalkyl acrylate or methacrylate, and a dialkyldialkyl ammonium halide. The acrylamide or methacrylamide to cationic monomer molar ratio of the polymer is about 70:30 to 95:5, the polymer having an I.V. in 1.0N KCl of about 1.0 to 7.0 dl/g and being present in a compatible and viscosifying amount; the thickened brine characterized by being substantially non-dilatent.

  14. Biofilm Formation in Microscopic Double Emulsion Droplets

    NASA Astrophysics Data System (ADS)

    Chang, Connie; Weitz, David

    2012-02-01

    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.

  15. Systematic failure of static nucleus-nucleus potential to explore sub-barrier fusion dynamics

    NASA Astrophysics Data System (ADS)

    Singh Gautam, Manjeet

    2015-05-01

    This paper addresses the validity of the static Woods-Saxon potential and the energy dependent Woods-Saxon potential (EDWSP) for description of sub-barrier fusion dynamics. The low lying surface vibrations of colliding nuclei and neutron transfer channels are found to be major factors responsible for fusion enhancement at sub-barrier energies. Theoretical calculations based upon the static Woods-Saxon potential obtained using the one-dimensional Wong formula fail to explain the energy dependence of the sub-barrier fusion cross-section of {}2040C{}{}a+{}2246,48,50T{}{}i systems. The role of inelastic surface vibrations is properly entertained within the context of coupled channel calculations performed using the CCFULL code. However, the EDWSP model, in conjunction with the one-dimensional Wong formula, accurately explains the sub-barrier fusion enhancement of {}2040C{}{}a+{}2246,48,50T{}{}i systems and simulates the influence of nuclear structure degrees of freedom, such as the inelastic surface vibrational states of colliding pairs. In EDWSP model calculations, a wide range of diffuseness parameters, ranging from a=0.96 fm to a=0.85 fm, which is much larger than a value ≤ft( a=0.65 fm \\right) extracted from the elastic scattering data, is required to bring the observed fusion enhancement.

  16. On the photon production in nucleus-nucleus collisions at high energy

    NASA Astrophysics Data System (ADS)

    Tarasov, Y. A.; Antonenko, V. G.

    1995-03-01

    A modified Landau hydrodynamical model is applied to study hard thermal photon production in central heavy-ion collisions at LHC, RHIC and SPS energies. It is shown that the phase transition from quark-gluon plasma into hadrons in consequence of the thermodynamical expansion is close to the second order phase transition if a resonance production is taken into account. Hard direct photon emission is also investigated with consideration of nuclear shadowing effect on structure function of quarks and gluons. Also ππ photon background is investigated. It is demonstrated that at the LHC energy photon yield from the quark-gluon plasma in the photon transversal momentum k ⊥ range from 5 to 25 GeV/c exceeds both the background and the direct photon yield. This conclusion may be important for the quark-gluon plasma diagnostic aims. It is also shown that for the LHC energy the thermal photon yield in the present model essentially exceeds this yield obtained in the Bjorken scaling model.

  17. Multiple pion and kaon production in high energy nucleus-nucleus collisions: measurements versus specific models

    NASA Astrophysics Data System (ADS)

    Guptaroy, P.; de, Bh.; Bhattacharyya, S.; Bhattacharyya, D. P.

    The pion and kaon rapidity densities and the nature of kaon-pion ratios offer two very prominent and crucial physical observables on which modestly sufficient data for heavy nucleus collisions are available to date. In the light of two sets of models - one purely phenomenological and the other with a modest degree of a dynamical basis - we try to examine the state of agreement between calculations and experimental results obtainable from the past and the latest measurements. Impact and implications of all these would also finally be spelt out.

  18. Forward Physics in Proton-Nucleus and Nucleus-Nucleus Collisions

    SciTech Connect

    Nemchik, J.; Potashnikova, I. K.

    2008-10-13

    We present an universal treatment for a substantial nuclear suppression representing a common feature of all known reactions on nuclear targets (forward production of high-p{sub T} hadrons, production of direct photons, the Drell-Yan process, heavy flavor production, etc.). Such a suppression at large Feynman x{sub F}, corresponding to region of minimal light-cone momentum fraction variable x{sub 2} in nuclei, is tempting to interpret as a manifestation of coherence or the Color Glass Condensate. We demonstrate, however, that it is actually a simple consequence of energy conservation and takes place even at low energies, where no effects of coherence are possible. We analyze this common suppression mechanism for several processes performing model predictions in the light-cone dipole approach. Our calculations agree with the data.

  19. Multiparticle azimuthal correlations of negative pions in nucleus-nucleus collisions

    SciTech Connect

    Chkhaidze, L. V. Djobava, T. D.; Kharkhelauri, L. L.; Kladnitskaya, E. N.

    2012-07-15

    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.

  20. Systematics of the release of residual nuclei from relativistic nucleus-nucleus interactions

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Israel, M. H.; Klarmann, J.; Garrard, T. L.; Kertzmann, M. P.

    1987-01-01

    Relativistic nuclei of krypton, xenon, holmium, and gold, accelerated in a partially stripped state to a maximum rigidity of about 5.6 GeV, interacting with targets of aluminum, carbon, and polyethylene are examined. For each projectile and target combination, determinations are made for the total and partial charge changing cross sections for the production of lighter fragments. From these measurements, a new representation of the dependence of the total charge changing cross sections on beam and target charge is developed. Simple representations of the variation of the partial cross sections were identified with the charge of the produced fragments and shown to be dependent on the charge and energy of the beam. The fission of gold nuclei at high energies in these various targets has also been studied.

  1. Definite evidence of the Landau-Zener transition in nucleus-nucleus collisions

    SciTech Connect

    Imanishi, B.; von Oertzen, W.; Voit, H.

    1987-01-01

    It is shown that the Landau-Zener transition mechanism due to the formation of molecular orbitals of the active neutron exists in the inelastic scattering /sup 13/C(/sup 12/C, /sup 12/C)/sup 13/C/sup */ (3.086 MeV, (1/2)/sup +/). The evidence stems from characteristic changes of the angular distributions observed as a function of the incident energy.

  2. Exclusive glueball production in high-energy nucleus-nucleus collisions

    SciTech Connect

    Machado, M. V. T.; Silva, M. L. L. da

    2011-01-15

    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.

  3. Light-particle-complex-fragment coincidence cross sections from intermediate energy nucleus-nucleus collisions

    SciTech Connect

    Hasselquist, B.E.; Crawley, G.M.; Jacak, B.V.; Koenig, Z.M.; Westfall, G.D.; Yurkon, J.E.; Tickle, R.S.; Dufour, J.P.; Symons, T.J.M.

    1985-07-01

    Light-particle (Z

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

    PubMed

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

    2015-09-15

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

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

    NASA Technical Reports Server (NTRS)

    Kim, S.; Westmoreland, D.

    1994-01-01

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

  6. Dehydration of oil waste emulsions by means of flocculants

    SciTech Connect

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

    1995-05-01

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

  7. Image Charge Effects on the Formation of Pickering Emulsions.

    PubMed

    Wang, Hongzhi; Singh, Virendra; Behrens, Sven Holger

    2012-10-18

    Vigorous mixing of an aqueous particle dispersion with oil usually produces a particle-stabilized emulsion (a "Pickering emulsion"), the longevity of which depends on the particles' wetting properties. A known exception occurs when particles fail to adsorb to the oil-water interface created during mixing because of a strong repulsion between charges on the particle surface and similar charges on the oil-water interface; in this case, no Pickering emulsion is formed. Here, we present experimental evidence that the rarely considered electrostatic image force can cause a much bigger hindrance to particle adsorption and prevent the formation of Pickering emulsions even when the particle interaction with the interface charge is attractive. A simple theoretical estimate confirms the observed magnitude of this effect and points at an important limitation of Pickering emulsification, a technology with widespread industrial applications and increasing popularity in materials research and development.

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

    PubMed

    Xia, Lixin; Lu, Shiwei; Cao, Guoying

    2004-03-15

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

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

    PubMed

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

    2014-06-15

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

  10. Reduced Fat Food Emulsions: Physicochemical, Sensory, and Biological Aspects.

    PubMed

    Chung, Cheryl; Smith, Gordon; Degner, Brian; McClements, David Julian

    2016-01-01

    Fat plays multiple important roles in imparting desirable sensory attributes to emulsion-based food products, such as sauces, dressings, soups, beverages, and desserts. However, there is concern that over consumption of fats leads to increased incidences of chronic diseases, such as obesity, coronary heart disease, and diabetes. Consequently, there is a need to develop reduced fat products with desirable sensory profiles that match those of their full-fat counterparts. The successful design of high quality reduced-fat products requires an understanding of the many roles that fat plays in determining the sensory attributes of food emulsions, and of appropriate strategies to replace some or all of these attributes. This paper reviews our current understanding of the influence of fat on the physicochemical and physiological attributes of food emulsions, and highlights some of the main approaches that can be used to create high quality emulsion-based food products with reduced fat contents.

  11. The effects of emulsifying agents on disposition of lipid-soluble drugs included in fat emulsion.

    PubMed

    Suzuki, Yasuyuki; Masumitsu, Yasushi; Okudaira, Kazuho; Hayashi, Masahiro

    2004-02-01

    The uses for drug delivery systems of two soybean oil fat emulsions prepared with an emulsifying agent, phosphatidyl choline (PC) or Pluronic F-127 (PLU), were examined comparatively in vivo and in vitro. In the presence of lipoprotein lipase (LPL) in vitro, the mean particle size of the PLU emulsion changed less than that of the PC emulsion. The production of non-esterified fatty acid (NEFA) from the PLU emulsion in the presence of LPL was smaller than that from the PC emulsion. These in vitro results indicate that the PLU emulsion is more stable than the PC emulsion. Plasma NEFA concentration following intravenous administration of the emulsions decreased with time for the PC emulsion, but was kept lower and constant for the PLU emulsion, supporting the in vitro stability data. The order of plasma cyclosporine A (CsA) concentration following intravenous administration in the above two emulsions and the mixed solution of polyethylene glycol 400 (PEG) and dimethylamide (DMA) in rats was PLU emulsion>PC emulsion>PEG/DMA solution. The plasma concentration was maintained higher and tissue distribution lower for the PLU emulsion than for other formulations. The uptake of oil violet (OV) into the rat parenchymal cells from the PLU emulsion was approximately half that from the PC emulsion, but the uptake into the Kupffer cells was almost equal in both emulsions. In conclusion, these emulsifying agents can control plasma elimination and tissue distribution of lipophilic drugs included in the emulsion. The use of the emulsion formulation makes it possible to avoid side effects through the reduction of drug uptake into non-targeted tissues.

  12. Generation of colloidal granules and capsules from double emulsion drops

    NASA Astrophysics Data System (ADS)

    Hess, Kathryn S.

    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

  13. Tunable Pickering emulsions with polymer-grafted lignin nanoparticles (PGLNs).

    PubMed

    Silmore, Kevin S; Gupta, Chetali; Washburn, Newell R

    2016-03-15

    Lignin is an abundant biopolymer that has native interfacial functions but aggregates strongly in aqueous media. Polyacrylamide was grafted onto kraft lignin nanoparticles using reversible addition-fragmentation chain transfer (RAFT) chemistry to form polymer-grafted lignin nanoparticles (PGLNs) that tune aggregation strength while retaining interfacial activities in forming Pickering emulsions. Polymer graft density on the particle surface, ionic strength, and initial water and cyclohexane volume fractions were varied and found to have profound effects on emulsion characteristics, including emulsion volume fraction, droplet size, and particle interfacial concentration that were attributed to changes in lignin aggregation and hydrophobic interactions. In particular, salt concentration was found to have a significant effect on aggregation, zeta potential, and interfacial tension, which was attributed to changes in solubility of both the kraft lignin and the polyacrylamide grafts. Dynamic light scattering, UV-vis spectroscopy, optical microscopy, and tensiometry were used to quantify emulsion properties and nanoparticle behavior. Under all conditions, the emulsions exhibited relatively fast creaming but were stable against coalescence and Ostwald ripening for a period of months. All emulsions were also oil-in-water (o/w) emulsions, as predicted by the Bancroft rule, and no catastrophic phase inversions were observed for any nanoparticle compositions. We conclude that lower grafting density of polyacrylamide on a lignin core resulted in high levels of interfacial activity, as characterized by higher concentration at the water-cyclohexane interface with a corresponding decrease in interfacial tension. These results indicate that the interfacial properties of polymer-grafted lignin nanoparticles are primarily due to the native hydrophobic interactions of the lignin core. These results suggest that the forces that drive aggregation are also correlated with interfacial

  14. Enhanced reductive dechlorination in columns treated with edible oil emulsion

    NASA Astrophysics Data System (ADS)

    Long, Cameron M.; Borden, Robert C.

    2006-09-01

    The effect of edible oil emulsion treatment on enhanced reductive dechlorination was evaluated in a 14 month laboratory column study. Experimental treatments included: (1) emulsified soybean oil and dilute HCl to inhibit biological activity; (2) emulsified oil only; (3) emulsified oil and anaerobic digester sludge; and (4) continuously feeding soluble substrate. A single application of emulsified oil was effective in generating strongly reducing, anaerobic conditions for over 14 months. PCE was rapidly reduced to cis-DCE in all three live columns. Bioaugmentation with a halorespiring enrichment culture resulted in complete dechlorination of PCE to ethene in the soluble substrate column (yeast extract and lactate). However, an additional treatment with a pulse of yeast extract and bioaugmentation culture was required to stimulate complete dechlorination in the emulsion treated columns. Once the dechlorinating population was established, the emulsion only column degraded PCE from 90-120 μM to below detection with concurrent ethene production in a 33 day contact time. The lower biodegradation rates in the emulsion treated columns compared to the soluble substrate column suggest that emulsified oil barriers may require a somewhat longer contact time for effective treatment. In the HCl inhibited column, partitioning of PCE to the retained oil substantially delayed PCE breakthrough. However, reduction of PCE to more soluble degradation products ( cis-DCE, VC and ethene) greatly reduced the impact of oil-water partitioning in live columns. There was only a small decline in the hydraulic conductivity ( K) of column #1 (low pH + emulsion, Kfinal/ Kinitial = 0.57) and column #2 (live + emulsion, Kfinal/ Kinitial = 0.73) indicating emulsion injection did not result in appreciable clogging of the clayey sand. However, K loss was greater in column #3 (sludge +emulsion, Kfinal/ Kinitial = 0.12) and column #4 (soluble substrate, Kfinal/ Kinitial = 0.03) indicating clogging due

  15. Stabilization/solidification of munition destruction waste by asphalt emulsion.

    PubMed

    Cervinkova, Marketa; Vondruska, Milan; Bednarik, Vratislav; Pazdera, Antonin

    2007-04-02

    Destruction of discarded military munitions in an explosion chamber produces two fractions of hazardous solid waste. The first one is scrap waste that remains in the chamber after explosion; the second one is fine dust waste, which is trapped on filters of gas products that are exhausted from the chamber after explosion. The technique of stabilization/solidification of the scrap waste by asphalt emulsion is described in this paper. The technique consists of simple mixing of the waste with anionic asphalt emulsion, or two-step mixing of the waste with cationic asphalt emulsion. These techniques are easy to use and the stabilized scrap waste proves low leachability of contained heavy metals assessed by TCLP test. Hence, it is possible to landfill the scrap waste stabilized by asphalt emulsion. If the dust waste, which has large specific surface, is stabilized by asphalt emulsion, it is not fully encapsulated; the results of the leaching tests do not meet the regulatory levels. However, the dust waste solidified by asphalt emulsion can be deposited into an asphalted disposal site of the landfill. The asphalt walls of the disposal site represent an efficient secondary barrier against pollutant release.

  16. Analyzing Benzene and Cyclohexane Emulsion Droplet Collisions on Ultramicroelectrodes.

    PubMed

    Li, Yan; Deng, Haiqiang; Dick, Jeffrey E; Bard, Allen J

    2015-11-03

    We report the collisions of single emulsion oil droplets with extremely low dielectric constants (e.g., benzene, ε of 2.27, or cyclohexane, ε of 2.02) as studied via emulsion droplet reactor (EDR) on an ultramicroelectrode (UME). By applying appropriate potentials to the UME, we observed the electrochemical effects of single-collision signals from the bulk electrolysis of single emulsion droplets. Different hydrophobic redox species (ferrocene, decamethyl-ferrocene, or metalloporphyrin) were trapped in a mixed benzene (or cyclohexane) oil-in-water emulsion using an ionic liquid as the supporting electrolyte and emulsifier. The emulsions were prepared using ultrasonic processing. Spike-like responses were observed in each i-t response due to the complete electrolysis of all of the above-mentioned redox species within the droplet. On the basis of these single-particle collision results, the collision frequency, size distribution, i-t decay behavior of the emulsion droplets, and possible mechanisms are analyzed and discussed. This work demonstrated that bulk electrolysis can be achieved in a few seconds in these attoliter reactors, suggesting many applications, such as analysis and electrosynthesis in low dielectric constant solvents, which have a much broader potential window.

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

    PubMed

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

    2009-05-21

    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.

  18. Stability of Emulsions Containing Both Sodium Caseinate and Tween 20.

    PubMed

    Dickinson; Ritzoulis; Povey

    1999-04-15

    The creaming and rheology of oil-in-water emulsions (30 vol% n-tetradecane, pH 6.8) stabilized by a mixture of commercial sodium caseinate and the non-ionic emulsifier polyoxyethylene sorbitan monolaurate (Tween 20) has been investigated at 21 degrees C. The presence of sufficient Tween 20 to displace most of the protein from the emulsion droplet surface leads to greatly enhanced emulsion creaming (and strongly non-Newtonian rheology) which is indicative of depletion flocculation by nonadsorbed surface-active material (protein and emulsifier). In emulsions containing a constant amount of surface-active material, the replacement of a very small fraction of Tween 20 by caseinate in a stable pure Tween 20 emulsion leads to enhanced creaming for a small fraction of the droplets, and this fraction increases with increasing replacement of emulsifier by protein. This behavior is probably due to depletion flocculation, although an alternative bridging mechanism is also a possibility. The overall stability of these sets of emulsions can be represented in terms of a global stability diagram containing regions of bridging flocculation and coalescence (low content of surface-active material), stability (intermediate content), and depletion flocculation (high content). Copyright 1999 Academic Press.

  19. Droplet-based microfluidics and the dynamics of emulsions

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  20. Chemical stability of teniposide in aqueous and parenteral lipid emulsions.

    PubMed

    Wang, Jing; Cui, Yue; Tang, Xing

    2009-04-01

    The purpose of this study was to investigate the degradation kinetics of teniposide in lipid emulsion and aqueous solution. The chemical stability of teniposide in lipid emulsion and aqueous solution at various pH values and temperatures was monitored by high-performance liquid chromatography. In addition, the viscosities of emulsion at different temperatures were investigated. The degradation of teniposide both in emulsion and in aqueous solution was shown to follow pseudo-first-order degradation kinetics. The t (1/2) values of teniposide lipid emulsion (TLE) and the aqueous solution were 80 and 2.6 days at 10 degrees C, respectively. Under the most stable pH range of 6.0-6.5, stability of teniposide in the emulsion increased more than 30-fold compared with that in aqueous solution. Furthermore, there was a difference between the shelf life of TLE actually measured (29 days) at 10 degrees C and the one deduced (15 days) from the degradation data of high temperatures by Arrhenius equation. It could be hypothesized that the difference was due to a slower diffusion of teniposide from oil phase to aqueous phase at the lower temperatures, which would be a speed-limited process in the degradation of TLE. The results of viscosity test confirmed the presumption.

  1. Effects of alpha-tocopherol, beta-carotene, and soy isoflavones on lipid oxidation of structured lipid-based emulsions.

    PubMed

    Osborn-Barnes, Hannah T; Akoh, Casimir C

    2003-11-05

    Structured lipids (SLs) are triacylglycerols that have been modified to change the fatty acid composition and/or positional distribution in the glycerol backbone by chemically and/or enzymatically catalyzed reactions and/or genetic engineering. Ten percent oil-in-water emulsions were formulated with a canola oil/caprylic acid SL and stabilized with 0.5% whey protein isolate (WPI) or sucrose fatty acid ester (SFE). The effects of alpha-tocopherol, beta-carotene, genistein, and daidzein (added at 0.02 wt % of oil) on lipid oxidation were evaluated over a 15-day period in emulsion samples. Significantly (p < 0.05) less total oxidation (calculated from peroxide value and anisidine value measurements) occurred in the WPI emulsions compared to their SFE counterparts. In this study, alpha-tocopherol, beta-carotene, and both soy isoflavones exhibited prooxidant activities in SFE emulsions. Because of their ability to exhibit prooxidant activity under certain conditions, manufacturers must experiment with these compounds before adding them to SL-based products as functional ingredients.

  2. Physical and antimicrobial properties of thyme oil emulsions stabilized by ovalbumin and gum arabic.

    PubMed

    Niu, Fuge; Pan, Weichun; Su, Yujie; Yang, Yanjun

    2016-12-01

    Natural biopolymer stabilized oil-in-water emulsions were formulated using ovalbumin (OVA), gum arabic (GA) solutions and their complexes. The influence of interfacial structure of emulsion (OVA-GA bilayer and OVA/GA complexes emulsions) on the physical properties and antimicrobial activity of thyme oil (TO) emulsion against Escherichia coli (E. coli) was evaluated. The results revealed that the two types of emulsions with different oil phase compositions remained stable during a long storage period. The oil phase composition had an appreciable influence on the mean particle diameter and retention of the TO emulsions. The stable emulsion showed a higher minimum inhibitory concentration (MIC), and the TO emulsions showed an improved long-term antimicrobial activity compared to the pure thyme oil, especially complexes emulsion at pH 4.0. These results provided useful information for developing protection and delivery systems for essential oil using biopolymer.

  3. Cardiac Depression Induced by Cocaine or Cocaethylene are Alleviated by Lipid Emulsion More Effectively Than by Sulfobutylether β-Cyclodextrin

    PubMed Central

    Fettiplace, Michael R.; Pichurko, Adrian; Ripper, Richard; Lin, Bocheng; Kowal, Katarzyna; Lis, Kinga; Schwartz, David; Feinstein, Douglas L.; Rubinstein, Israel; Weinberg, Guy

    2015-01-01

    Objectives Cocaine intoxication leads to over 500,000 emergency department visits annually in the USA and ethanol co-intoxication occurs in 34% of those cases. Cardiotoxicity is an ominous complication of cocaine and cocaethylene overdose for which no specific antidote exists. Because infusion of lipid emulsion (Intralipid) can treat lipophilic local anesthetic toxicity and cocaine is an amphipathic local anesthetic, the authors tested whether lipid emulsion could attenuate cocaine cardiotoxicity in vivo. The effects of lipid emulsion were compared with the metabolically inert sulfobutylether-β-cyclodextrin (Captisol) in an isolated heart model of cocaine and cocaethylene toxicity to determine if capture alone could exert similar benefit as lipid emulsion which exhibits multi-modal effects. The authors then tested if cocaine and cocaethylene, like bupivacaine, inhibit lipid-based metabolism in isolated cardiac mitochondria. Methods For whole animal experiments, Sprague-Dawley rats were anesthetized, instrumented, and pretreated with lipid emulsion followed by a continuous infusion of cocaine to assess time of onset of cocaine toxicity. For ex vivo experiments, rat hearts were placed onto a non-recirculating Langendorff system perfused with Krebs-Henseleit solution. Heart rate, left ventricle maximum developed pressure (LVdevP), left ventricle diastolic pressure (LVDP), maximum rate of contraction (+dP/dtmax), maximum rate of relaxation (−dP/dtmax), rate-pressure product (RPP = heart rate*LVdevP), and line pressure were monitored continuously during the experiment. A dose-response to cocaine (10, 30, 50, and 100 μM) and cocaethylene (10, 30, 50 μM) was generated in the absence or presence of either 0.25% lipid emulsion, or sulfobutyl-β-cyclodextrin. Substrate-specific rates of oxygen consumption were measured in interfibrillar cardiac mitochondria in the presence of cocaine, cocaethylene, ecgonine, and benzoylecgonine. Results Treatment with lipid emulsion

  4. Emulsion templated open porous membranes for protein purification.

    PubMed

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

    2011-04-29

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

  5. Hydroplasticization of polymers: model predictions and application to emulsion polymers.

    PubMed

    Tsavalas, John G; Sundberg, Donald C

    2010-05-18

    The plasticization of a polymer by solvent has a dramatic impact on both its thermal and mechanical behavior. With increasing demand for zero volatile organic compound materials and coatings, water is often the sole solvent used both in the polymer synthesis and in formulation and application; latex colloids derived from emulsion polymerization are a good example. The impact of water on the glass transition temperature of a polymer thus becomes a critical physical property to predict. It has been shown here that in order to do so, one simply needs the dry state glass transition temperature (T(g)) of the (co)polymer, the T(g) of water, and the saturated weight fraction of water for the sample in question. Facile calculation of the later can be achieved using water sorption data and the group additivity method. With these readily available data, we show that a form of the Flory-Fox equation can be used to predict the hydroplasticized state of copolymers in exceptional agreement with direct experimental measurement. Furthermore, extending the prediction to include the impact of the degree of ionization for pH responsive components, only with extra knowledge of the pK(a), was also validated by experiment.

  6. Sculpting Pickering Emulsion Droplets by Arrest and Jamming

    NASA Astrophysics Data System (ADS)

    Burke, Christopher; Wei, Zengyi; Caggioni, Marco; Spicer, Patrick; Atherton, Tim

    Pickering emulsion droplets can be arrested into non-spherical shapes--useful for applications such as active delivery--through a general mechanism of deformation followed by absorption of additional colloidal particles onto the interface, relaxation of the droplet caused by surface tension and arrest at some point due to crowding of the particles. We perform simulations of the arrest process to clarify the relative importance of diffusive rearrangement of particles and collective forcing due to surface evolution. Experiment and theory are compared, giving insight into the stability of the resulting capsules and the robustness of the production process for higher-throughput production in, for example, microfluidic systems. We adapt theoretical tools from the jamming literature to better understand the arrested configurations and long timescale evolution of the system: using linear programming and a penalty function approach, we identify unjamming motions in kinetically arrested states. We propose a paradigm of ``metric jamming'' to describe the limiting behavior of this class of system: a structure is metric-jammed if it is stable with respect to collective motion of the particles as well as evolution of the hypersurface on which the packing is embedded. Supported by a Cottrell Award from the Research Corporation for Science Advancement.

  7. Comment to "The pharmacopeial evolution of Intralipid injectable emulsion in plastic containers: from a coarse to a fine emulsion".

    PubMed

    Ellborg, Anders; Ferreira, Denise; Mohammadnejad, Javad; Wärnheim, Torbjörn

    2010-06-15

    The droplet size distribution of 50 batches of multi-chamber bags containing the parenteral nutrition emulsions Intralipid (Kabiven and Kabiven Peripheral) or Structolipid (StructoKabiven and StructoKabiven Peripheral), respectively, has been investigated. The results show that the non-compounded lipid emulsions analysed are in compliance with the United States Pharmacopeia (USP) chapter 729, Method II limit for the droplet size distribution, PFAT(5)<0.05%.

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

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

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

    PubMed

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

    2014-01-01

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

  10. Use of microwave radiation in separating emulsions and dispersions of hydrocarbons and water

    SciTech Connect

    Wolf, N.O.

    1986-04-15

    A method is described for enhancing the separation of hydrocarbon and water from an emulsion or dispersion thereof comprising the steps of subjecting the emulsion or dispersion to microwave radiation in the range of one millimeter to 30 centimeters and heating the microwave irradiated emulsion or dispersion to a separating temperature using conventional heating means. A method is also described for enhancing the separation of hydrocarbon and water from from dispersion or emulsion thereof in the presence of chemical deemulsifiers comprising the steps of contacting the dispersion or emulsion and chemical deemulsifiers with microwave energy before heating the emulsion or dispersion to a separating temperature using conventional heating means.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  12. Development of novel zein-sodium caseinate nanoparticle (ZP)-stabilized emulsion films for improved water barrier properties via emulsion/solvent evaporation.

    PubMed

    Wang, Li-Juan; Yin, Ye-Chong; Yin, Shou-Wei; Yang, Xiao-Quan; Shi, Wei-Jian; Tang, Chuan-He; Wang, Jin-Mei

    2013-11-20

    This work attempted to develop novel high barrier zein/SC nanoparticle (ZP)-stabilized emulsion films through microfluidic emulsification (ZPE films) or in combination with solvent (ethyl acetate) evaporation techniques (ZPE-EA films). Some physical properties, including tensile and optical properties, water vapor permeability (WVP), and surface hydrophobicity, as well as the microstructure of ZP-stabilized emulsion films were evaluated and compared with SC emulsion (SCE) films. The emulsion/solvent evaporation approach reduced lipid droplets of ZP-stabilized emulsions, and lipid droplets of ZP-stabilized emulsions were similar to or slightly lower than that of SC emulsions. However, ZP- and SC-stabilized emulsion films exhibited a completely different microstructure, nanoscalar lipid droplets were homogeneously distributed in the ZPE film matrix and interpenetrating protein-oil complex networks occurred within ZPE-EA films, whereas SCE films presented a heterogeneous microstructure. The different stabilization mechanisms against creaming or coalescence during film formation accounted for the preceding discrepancy of the microstructures between ZP-and SC-stabilized emulsion films. Interestingly, ZP-stabilized emulsion films exhibited a better water barrier efficiency, and the WVP values were only 40-50% of SCE films. A schematic representation for the formation of ZP-stabilized emulsion films was proposed to relate the physical performance of the films with their microstructure and to elucidate the possible forming mechanism of the films.

  13. Breaking oil-in-water emulsions stabilized by yeast.

    PubMed

    Furtado, Guilherme F; Picone, Carolina S F; Cuellar, Maria C; Cunha, Rosiane L

    2015-04-01

    Several biotechnological processes can show an undesirable formation of emulsions making difficult phase separation and product recovery. The breakup of oil-in-water emulsions stabilized by yeast was studied using different physical and chemical methods. These emulsions were composed by deionized water, hexadecane and commercial yeast (Saccharomyces cerevisiae). The stability of the emulsions was evaluated varying the yeast concentration from 7.47 to 22.11% (w/w) and the phases obtained after gravity separation were evaluated on chemical composition, droplet size distribution, rheological behavior and optical microscopy. The cream phase showed kinetic stability attributed to mechanisms as electrostatic repulsion between the droplets, a possible Pickering-type stabilization and the viscoelastic properties of the concentrated emulsion. Oil recovery from cream phase was performed using gravity separation, centrifugation, heating and addition of demulsifier agents (alcohols and magnetic nanoparticles). Long centrifugation time and high centrifugal forces (2 h/150,000×g) were necessary to obtain a complete oil recovery. The heat treatment (60°C) was not enough to promote a satisfactory oil separation. Addition of alcohols followed by centrifugation enhanced oil recovery: butanol addition allowed almost complete phase separation of the emulsion while ethanol addition resulted in 84% of oil recovery. Implementation of this method, however, would require additional steps for solvent separation. Addition of charged magnetic nanoparticles was effective by interacting electrostatically with the interface, resulting in emulsion destabilization under a magnetic field. This method reached almost 96% of oil recovery and it was potentially advantageous since no additional steps might be necessary for further purifying the recovered oil.

  14. To Model Chemical Reactivity in Heterogeneous Emulsions, Think Homogeneous Microemulsions.

    PubMed

    Bravo-Díaz, Carlos; Romsted, Laurence Stuart; Liu, Changyao; Losada-Barreiro, Sonia; Pastoriza-Gallego, Maria José; Gao, Xiang; Gu, Qing; Krishnan, Gunaseelan; Sánchez-Paz, Verónica; Zhang, Yongliang; Dar, Aijaz Ahmad

    2015-08-25

    Two important and unsolved problems in the food industry and also fundamental questions in colloid chemistry are how to measure molecular distributions, especially antioxidants (AOs), and how to model chemical reactivity, including AO efficiency in opaque emulsions. The key to understanding reactivity in organized surfactant media is that reaction mechanisms are consistent with a discrete structures-separate continuous regions duality. Aggregate structures in emulsions are determined by highly cooperative but weak organizing forces that allow reactants to diffuse at rates approaching their diffusion-controlled limit. Reactant distributions for slow thermal bimolecular reactions are in dynamic equilibrium, and their distributions are proportional to their relative solubilities in the oil, interfacial, and aqueous regions. Our chemical kinetic method is grounded in thermodynamics and combines a pseudophase model with methods for monitoring the reactions of AOs with a hydrophobic arenediazonium ion probe in opaque emulsions. We introduce (a) the logic and basic assumptions of the pseudophase model used to define the distributions of AOs among the oil, interfacial, and aqueous regions in microemulsions and emulsions and (b) the dye derivatization and linear sweep voltammetry methods for monitoring the rates of reaction in opaque emulsions. Our results show that this approach provides a unique, versatile, and robust method for obtaining quantitative estimates of AO partition coefficients or partition constants and distributions and interfacial rate constants in emulsions. The examples provided illustrate the effects of various emulsion properties on AO distributions such as oil hydrophobicity, emulsifier structure and HLB, temperature, droplet size, surfactant charge, and acidity on reactant distributions. Finally, we show that the chemical kinetic method provides a natural explanation for the cut-off effect, a maximum followed by a sharp reduction in AO efficiency with

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

    PubMed

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

    2013-12-18

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

  16. Interaction of polyhexamethylene biguanide hydrochloride (PHMB) with phosphatidylcholine containing o/w emulsion and consequences for microbicidal efficacy and cytotoxicity.

    PubMed

    Müller, Gerald; Koburger, Torsten; Kramer, Axel

    2013-01-25

    Oil-in-water (o/w) emulsions containing egg yolk phosphatidylcholine (EPC) were combined with aqueous polyhexamethylene biguanide hydrochloride (PHMB). The PHMB concentration in the aqueous phase was estimated by filtration centrifugation experiments. In parallel, PHMB concentration was assessed utilizing cytotoxicity assays (neutral red) on cultured murine fibroblasts (L929 cells) and tests of bactericidal efficacy on either Pseudomonas aeruginosa or Staphylococcus aureus. Biological tests were performed in cell culture medium. Filtration centrifugation experiments demonstrated much higher aqueous PHMB concentrations than did the assays for biologically effective PHMB. Therefore, biological test systems should preferably be used to verify effective PHMB concentrations. Tests of microbicidal efficacy in which the same 0.05% PHMB o/w emulsion was re-used 8 times revealed a drug delivery system activated by the presence of test bacteria.

  17. Evaluation of percutaneous permeation of repellent DEET and sunscreen oxybenzone from emulsion-based formulations in artificial membrane and human skin

    PubMed Central

    Wang, Tao; Miller, Donald; Burczynski, Frank; Gu, Xiaochen

    2014-01-01

    Insect repellent DEET and sunscreen ingredient oxybenzone play an essential role in minimizing vector-borne diseases and skin cancers. The purpose of this study was to investigate the effects of emulsion type, addition of thickening agent and droplet size in three emulsion-based lotions on percutaneous permeation of DEET and oxybenzone using in vitro diffusion experiments, in order to minimize overall systemic permeation of the substances. Formulation C (water-in-oil emulsion) significantly increased overall permeation of DEET through human skin (56%) compared to Formulation A (oil-in-water emulsion). Formulation B (oil-in-water emulsion with thickening agent xanthan gum) significantly decreased the size of oil droplet containing DEET (16%), but no effect on oil droplets containing oxybenzone. Adding xanthan gum also increased overall permeation of DEET and oxybenzone (21% and 150%) when compared to Formulation A; presence of both ingredients in Formulation B further increased their permeation (36% and 23%) in comparison to its single counterparts. Overall permeation of oxybenzone through LDPE was significantly higher by 26%–628% than that through human skin; overall permeation of DEET through human skin was significantly higher by 64%–338% than that through LDPE. PMID:26579363

  18. Genesis of emulsion texture due to magma mixing: a case study from Chotanagpur Granite Gneiss Complex of Eastern India

    NASA Astrophysics Data System (ADS)

    Gogoi, Bibhuti; Saikia, Ashima; Ahmad, Mansoor

    2016-04-01

    The emulsion texture is a rare magma mixing feature in which rounded bodies of one magmatic phase remain dispersed in the other coherent phase (Freundt and Schmincke, 1992). This type of special texture in hybrid rocks can significantly contribute toward understanding the mechanisms facilitating magma mixing and magma chamber dynamics involving two disparate magmas as the exact processes by which mixing occurs still remain unclear. Recent developments in microfluidics have greatly helped us to understand the complex processes governing magma mixing occurring at micro-level. Presented work uses some of the results obtained from microfluidic experiments with a view to understand the formation mechanism of emulsions preserved in the hybrid rocks of the Ghansura Rhyolite Dome (GRD) of Proterozoic Chotanagpur Granite Gneiss Complex (CGGC), Eastern India. The GRD has preserved hybrid rocks displaying emulsion texture that formed due to the interaction of a phenocryst-rich basaltic magma and host rhyolite magma. The emulsions are more or less spherical in shape and dominantly composed of amphibole having biotite rinds set in a matrix of biotite, plagioclase, K-feldspar and quartz. Amphibole compositions were determined from the core of the emulsions to the rim with a view to check for cationic substitutions. The amphibole constituting the emulsions is actinolite in composition, and commonly shows tschermakite (Ts) and pargasite (Prg) substitutions. From petrographical and mineral-chemical analyses we infer that when mafic magma, containing phenocrysts of augite, came in contact with felsic magma, diffusion of cations like H+, Al3+and others occurred from the felsic to the mafic system. These cations reacted with the clinopyroxene phenocrysts in the mafic magma to form amphibole (actinolite) crystals. The formation of amphibole crystals in the mafic system greatly increased the viscosity of the system allowing the amphibole crystals to venture into the adjacent felsic

  19. Delivery of Chlorambucil Using an Acoustically-Triggered, Perfluoropentane Emulsion

    PubMed Central

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

    2010-01-01

    Ultrasound-mediated delivery systems have mainly focused on microbubble contrast agents as carriers of drugs or genetic material. This study utilizes micron-sized, perfluoropentane (PFP) emulsions as carriers for chlorambucil (CHL), a lipophilic chemotherapeutic. The release of CHL is achieved via acoustic droplet vaporization (ADV), whereby the superheated emulsion is converted into gas bubbles using ultrasound. Emulsions were made using an albumin shell and soybean oil as the CHL carrier. The ratio of the PFP to soybean oil phases in the droplets, as well as the fraction of droplets that vaporize per ultrasound exposure were shown to correlate with droplet diameter. A 60-minute incubation with the CHL-loaded emulsion caused a 46.7% cellular growth inhibition, whereas incubation with the CHL-loaded emulsion that was exposed to ultrasound at 6.3 MHz caused an 84.3% growth inhibition. This difference was statistically significant (p < 0.01), signifying that ADV can be used as a method to substantially enhance drug delivery. PMID:20691925

  20. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project is to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, is used to remove inhibitory byproducts during fermentation; thus, improving the yield while reducing the need for fresh water. The key objectives of this study are: Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems; Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system; Investigate the effect of gravity on emulsion coalescence within the membrane unit; Access the effect of water re-use on fermentation yields in a model microbial system; Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts; Work for the coming year will focus on the determination of toxicity of various solvents, selection of the emulsifying agents, as well as characterizing the mass transfer of hollow-fiber contactors.

  1. Multiwalled Carbon Nanotubes at the Interface of Pickering Emulsions.

    PubMed

    Briggs, Nicholas M; Weston, Javen S; Li, Brian; Venkataramani, Deepika; Aichele, Clint P; Harwell, Jeffrey H; Crossley, Steven P

    2015-12-08

    Carbon nanotubes exhibit very unique properties in biphasic systems. Their interparticle attraction leads to reduced droplet coalescence rates and corresponding improvements in emulsion stability. Here we use covalent and noncovalent techniques to modify the hydrophilicity of multiwalled carbon nanotubes (MWCNTs) and study their resulting behavior at an oil-water interface. By using both paraffin wax/water and dodecane/water systems, the thickness of the layer of MWNTs at the interface and resulting emulsion stability are shown to vary significantly with the approach used to modify the MWNTs. Increased hydrophilicity of the MWNTs shifts the emulsions from water-in-oil to oil-in-water. The stability of the emulsion is found to correlate with the thickness of nanotubes populating the oil-water interface and relative strength of the carbon nanotube network. The addition of a surfactant decreases the thickness of nanotubes at the interface and enhances the overall interfacial area stabilized at the expense of increased droplet coalescence rates. To the best of our knowledge, this is the first time the interfacial thickness of modified carbon nanotubes has been quantified and correlated to emulsion stability.

  2. Engineering of acidic O/W emulsions with pectin.

    PubMed

    Alba, K; Sagis, L M C; Kontogiorgos, V

    2016-09-01

    Pectins with distinct molecular design were isolated by aqueous extraction at pH 2.0 or 6.0 and were examined in terms of their formation and stabilisation capacity of model n-alkane-in-water emulsions at acidic pH (pH 2.0). The properties and stability of the resulting emulsions were examined by means of droplet size distribution analysis, Lifshitz-Slyozov-Wagner modelling, bulk rheology, interfacial composition analysis, large-amplitude oscillatory surface dilatational rheology, electrokinetic analysis and fluorescence microscopy. Both pectin preparations were able to emulsify alkanes in water but exhibited distinct ageing characteristics. Emulsions prepared using pectin isolated at pH 6.0 were remarkably stable with respect to droplet growth after thirty days of ageing, while those prepared with pectin isolated at pH 2.0 destabilised rapidly. Examination of chemical composition of interfacial layers indicated multi-layered adsorption of pectins at the oil-water interface. The higher long-term stability of emulsions prepared with pectin isolated at high pH is attributed to mechanically stronger interfaces, the highly branched nature and the low hydrodynamic volume of the chains that result in effective steric stabilisation whereas acetyl and methyl contents do not contribute to the long-term stability. The present work shows that it is possible by tailoring the fine structure of pectin to engineer emulsions that operate in acidic environments.

  3. Cellulose Nanocrystals as Water in Water Emulsion Stabilizers

    NASA Astrophysics Data System (ADS)

    Peddireddy, Karthik Reddy; Capron, Isabelle; Nicolai, Taco; Benyahia, Lazhar

    Cellulose is the most abundant polymer on the earth. Thus, it is very much desirable to find as many practical applications as possible for it. Cellulose, in its original form, contains both amorphous and crystalline parts. It is possible to separate both parts by dissolving the amorphous part in concentrated sulfuric acid. The remaining crystalline cellulose part exist in the form of rod-like particles. The dimensions of the particles depend on the source. We produce the particles from the acid hydrolysis of cotton cellulose fibers. It results in cellulose nanocrystals (CNCs) with dimensions of ~150 nm x 6 nm x 6 nm. It is well known that CNCs could very efficiently stabilize oil in water (O/W) emulsions by forming very dense monolayers of CNCs at O-W interfaces. However, it is not yet known whether they could also stabilize water in water (W/W) emulsions. The W/W emulsions can be produced by any two incompatible polymers. It is challenging to find effective stabilizers for W/W emulsions due to ultralow interfacial tension and large interfacial thickness. In this talk, I will show the efficiency and effectiveness of these one-dimensional rods as W/W emulsion stabilizers.

  4. Thermodynamically Stable Pickering Emulsions Stabilized by Janus Dumbbells

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

    Janus particles have two sides with different, often opposite, surface properties. Janus dumbbell is one type of Janus particles that consists of two partially fused spherical lobes. It is possible to independently control the geometry and surface wettability of Janus dumbbells. Janus dumbbells can also be produced in a large quantity, making them useful for practical applications such as emulsion stabilization. In this work, we calculate the free energy of emulsion formation using amphiphilic Janus dumbbells as solid surfactants. In contrast to kinetically stable emulsions stabilized by homogeneous particles, emulsion stabilized by Janus dumbbells can be thermodynamically stable. There also exists an optimal radius of droplets that can be stabilized by infinite or limited number of amphiphilic dumbbells in the continuous phase. We demonstrate that the optimal radius of dumbbell-stabilized droplets can be predicted based on the volume of the dispersed phase and the volume fraction of dumbbells in the continuous phase. We believe our calculation will provide guidelines for using Janus dumbbells as colloid surfactants to generate stable emulsions.

  5. Induced phase transitions of nanoparticle-stabilized emulsions

    NASA Astrophysics Data System (ADS)

    Frijters, Stefan; Günther, Florian; Harting, Jens

    2013-11-01

    Nanoparticles can stabilize fluid-fluid interfaces over long timescales and are nowadays commonly used, e.g. in emulsions. However, their fundamental properties are as of yet poorly understood. Nanoparticle-stabilized emulsions can exhibit different phases, such as Pickering emulsions or bijels, which can be characterized by their different topologies and rheology. We investigate the effect of various initial conditions on random mixtures of two fluids and nanoparticles - in particular, the final state these systems will reach. For this, we use the well-established 3D lattice Boltzmann method, extended to allow for the added nanoparticles. After the evolution of the emulsions has stopped, we induce transitions from one state to another by gradually changing the wettability of the nanoparticles over time. This changes the preferential local curvature of the interfaces, which strongly affects the global state. We observe strong hysteresis effects because of the energy barrier presented by the necessary massive reordering of the particles. Being able to change emulsion states in situ has potential application possibilities in filtering technology, or creating particle scaffolds.

  6. Emulsion Inks for 3D Printing of High Porosity Materials.

    PubMed

    Sears, Nicholas A; Dhavalikar, Prachi S; Cosgriff-Hernandez, Elizabeth M

    2016-08-01

    Photocurable emulsion inks for use with solid freeform fabrication (SFF) to generate constructs with hierarchical porosity are presented. A high internal phase emulsion (HIPE) templating technique was utilized to prepare water-in-oil emulsions from a hydrophobic photopolymer, surfactant, and water. These HIPEs displayed strong shear thinning behavior that permitted layer-by-layer deposition into complex shapes and adequately high viscosity at low shear for shape retention after extrusion. Each layer was actively polymerized with an ultraviolet cure-on-dispense (CoD) technique and compositions with sufficient viscosity were able to produce tall, complex scaffolds with an internal lattice structure and microscale porosity. Evaluation of the rheological and cure properties indicated that the viscosity and cure rate both played an important role in print fidelity. These 3D printed polyHIPE constructs benefit from the tunable pore structure of emulsion templated material and the designed architecture of 3D printing. As such, these emulsion inks can be used to create ultra high porosity constructs with complex geometries and internal lattice structures not possible with traditional manufacturing techniques.

  7. Investigation of different emulsion systems for dermal delivery of nicotinamide.

    PubMed

    Tuncay, Sakine; Özer, Özgen

    2013-01-01

    Nicotinamide (NA) has been shown to have beneficial effects on several skin diseases such as tumor, acne vulgaris, photodamage, cellulite and atopic dermatitis. The purpose of this study was to develop a multiple emulsion and a microemulsion formulation as delivery systems for NA. A two-step process was used to prepare the W/O/W multiple emulsion. Optimum microemulsion formulation was selected by using construction of pseudo-ternary phase diagram. The physicochemical properties such as droplet size and viscosity measurements, stability studies were also evaluated. Ex-vivo permeation studies were performed with Franz-type diffusion cells and the samples were analysed by high performance liquid chromatography (HPLC). The permeation data showed that there was no significant difference between multiple emulsion and microemulsion (p > 0.05). Transepidermal water loss (TEWL) was also measured. As a result of TEWL studies, a slight increase of TEWL values was observed for microemulsion formulation on rat skin when compared with multiple emulsion and commercial formulation. The results suggested that microemulsion and multiple emulsion formulations could be new and alternative dosage forms for topical application of NA.

  8. Structural studies of commercial fat emulsions used in parenteral nutrition.

    PubMed

    Li, J; Caldwell, K D

    1994-11-01

    In this paper, we demonstrate that by employing a combination of sedimentation field-flow fractionation (sedFFF) and other characterization techniques, such as photon correlation spectroscopy (PCS) and freeze-fracture electron microscopy (EM), it is possible to show that commercial fat emulsions of similar overall chemical compositions not only may exhibit different size distributions but may have different densities as well. A closer look at the density difference between droplet and suspension medium, on the one hand, and the droplet size, on the other, demonstrates that fat emulsions may have structures other than the traditional oil droplet surrounded by a monolayer of surfactant. From our determined and simulated density differences, we propose that these emulsion droplets may have a multilayered surfactant arrangement as well as an inclusion of water vesicles in the oil phase of the emulsion. Freeze-fracture EM observations provide evidence to confirm the existence of such complex structures. These findings are supported by recent EM work from other laboratories, as well as through chemical verification of elevated water contents in the oil droplets of these emulsions.

  9. Structure and rheology of highly concentrated emulsions: a modern look

    NASA Astrophysics Data System (ADS)

    Malkin, A. Ya; Kulichikhin, V. G.

    2015-08-01

    The review concerns modern physicochemical, chemical and physical approaches to research into structural features that determine the rheological properties of highly concentrated emulsions. The structures and properties of various systems (suspensions, emulsions as well as transient forms including micellar colloidal solutions) are considered. The formation of highly concentrated emulsions is treated as the concentration glass transition leading to suppression of the molecular and supermolecular mobility and, subsequently, to the existence of a solid-like state of the systems in question. The emphasis is placed on analysis of visco-plasticity which manifests itself in the possibility for emulsions (unlike suspensions) to undergo irreversible deformation (to flow) at stresses exceeding some threshold (critical value) called the yield stress. The thixotropic nature of the transition through the yield stress, governed by the kinetics of the breakup/recovery of the inherent structure is considered in detail. It has been shown that structure formation in highly concentrated emulsions can extend to a macroscopic level and result in the onset of heterogeneity of a flow in the form of shear bands. The bibliography includes 202 references.

  10. Double emulsion formation through hierarchical flow-focusing microchannel

    NASA Astrophysics Data System (ADS)

    Azarmanesh, Milad; Farhadi, Mousa; Azizian, Pooya

    2016-03-01

    A microfluidic device is presented for creating double emulsions, controlling their sizes and also manipulating encapsulation processes. As a result of three immiscible liquids' interaction using dripping instability, double emulsions can be produced elegantly. Effects of dimensionless numbers are investigated which are Weber number of the inner phase (Wein), Capillary number of the inner droplet (Cain), and Capillary number of the outer droplet (Caout). They affect the formation process, inner and outer droplet size, and separation frequency. Direct numerical simulation of governing equations was done using volume of fluid method and adaptive mesh refinement technique. Two kinds of double emulsion formation, the two-step and the one-step, were simulated in which the thickness of the sheath of double emulsions can be adjusted. Altering each dimensionless number will change detachment location, outer droplet size and droplet formation period. Moreover, the decussate regime of the double-emulsion/empty-droplet is observed in low Wein. This phenomenon can be obtained by adjusting the Wein in which the maximum size of the sheath is discovered. Also, the results show that Cain has significant influence on the outer droplet size in the two-step process, while Caout affects the sheath in the one-step formation considerably.

  11. Treatment methods for breaking certain oil and water emulsions

    DOEpatents

    Sealock, Jr., L. John; Baker, Eddie G.; Elliott, Douglas C.

    1992-01-01

    Disclosed are treatment methods for breaking emulsions of petroleum oil and salt water, fatty oil and water, and those resulting from liquefication of organic material. The emulsions are broken by heating to a predetermined temperature at or above about 200.degree. C. and pressurizing to a predetermined pressure above the vapor pressure of water at the predetermined temperature to produce a heated and pressurized fluid. The heated and pressurized fluid is contained in a single vessel at the predetermined temperature and pressure for a predetermined period of time to effectively separate the emulsion into substantially distinct first and second phases, the first phase comprising primarily the petroleum oil, the second phase comprising primarily the water. The first and second phases are separately withdrawn from the vessel at a withdraw temperature between about 200.degree. C. and 374.degree. C. and a withdraw pressure above the vapor pressure of water at the withdraw temperature. Where solids are present in the certain emulsions, the above described treatment may also effectively separate the certain emulsion into a substantially distinct third phase comprising primarily the solids.

  12. Use of oil-in-water emulsions to control fungal deterioration of strawberry jams.

    PubMed

    Ribes, Susana; Fuentes, Ana; Talens, Pau; Barat, José M

    2016-11-15

    This work aimed to control the fungal deterioration of strawberry jams. The antifungal activity of the clove, cinnamon leaf, lemon and mandarin essential oils and their effectiveness in oil-in-water emulsions were evaluated. According to the results obtained, only clove and cinnamon leaf oils were selected to prepare emulsions. All the tested emulsions were stable, independently the amount of polymer and essential oil used. Essential oil loss was affected by the amount of polymer employed to prepare the emulsions. The oil-in-water emulsions with 5.0mg/g xanthan gum, and with 0.55mg/g clove or 0.65mg/g cinnamon leaf essential oil, were used for the in vivo tests. The jams prepared with the oil-in-water emulsions showed a lower fungal decay compared with jams without emulsion. The present work demonstrated that emulsions can be employed to prevent strawberry jam mould spoilage.

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

    NASA Astrophysics Data System (ADS)

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

    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.

  14. An update on safety and immunogenicity of vaccines containing emulsion-based adjuvants.

    PubMed

    Fox, Christopher B; Haensler, Jean

    2013-07-01

    With the exception of alum, emulsion-based vaccine adjuvants have been administered to far more people than any other adjuvant, especially since the 2009 H1N1 influenza pandemic. The number of clinical safety and immunogenicity evaluations of vaccines containing emulsion adjuvants has correspondingly mushroomed. In this review, the authors introduce emulsion adjuvant composition and history before detailing the most recent findings from clinical and postmarketing data regarding the effects of emulsion adjuvants on vaccine immunogenicity and safety, with emphasis on the most widely distributed emulsion adjuvants, MF59® and AS03. The authors also present a summary of other emulsion adjuvants in clinical development and indicate promising avenues for future emulsion-based adjuvant development. Overall, emulsion adjuvants have demonstrated potent adjuvant activity across a number of disease indications along with acceptable safety profiles.

  15. Hemp Sesbania (Sesbania exaltata) control in rice (Oryza sativa) with the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene formulated in an invert emulsion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In greenhouse and field experiments, an invert emulsion (MSG 8.25) was tested with dried, formulated spores of the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene, a highly virulent pathogen of the leguminous weed Aeschynomene virginica (northern jointvetch), but considered “...

  16. The complexity of prescribing intravenous lipid emulsions.

    PubMed

    Waitzberg, Dan Linetzky; Torrinhas, Raquel Susana

    2015-01-01

    Intravenous lipid emulsions (LEs) are relevant for patients receiving parenteral nutrition because they prevent the depletion of essential fatty acids (FAs) and, as a highly dense energy source, enable the reduction of glucose provision, thereby decreasing the risks of hyperglycemia and hepatic impairment. The prescription of LEs is complex, due mainly to their distinct FA components, which may alter the immune response in different ways and distinctly influence inflammation, oxidative stress and blood coagulation according to their biochemical properties. In addition, an excess of other LE components, such as phospholipids and phytosterols, may be associated with hepatic steatosis and dysfunction. These associations do not represent direct risks or obstacles to LE use in metabolically stable patients but can render the choice of the best LE for hypermetabolic patients difficult. The infusion of LEs according to the available guidelines provides more benefit than harm and should be part of exclusive parenteral nutrition regimens or complement enteral nutrition when appropriate. The patient's metabolic profile should guide the type of FA and amount of lipids that are provided. For critically ill hypermetabolic patients, growing evidence indicates that standard LEs based solely on soybean oil should be avoided in favor of new LEs containing medium-chain triglycerides, olive oil, or fish oil to decrease the provision of potentially oxidative, inflammatory/immunosuppressive, and prothrombotic n-6 FAs. In addition, as sources of eicosapentaenoic and docosahexaenoic acids, LEs containing fish oil may be important for critically ill patients because they allow better modulation of the immune response and likely reduce the length of intensive care unity stay. However, current evidence precludes the recommendation of a specific LE for clinical use in this patient population.

  17. Rapid enumeration of phage in monodisperse emulsions.

    PubMed

    Tjhung, Katrina F; Burnham, Sean; Anany, Hany; Griffiths, Mansel W; Derda, Ratmir

    2014-06-17

    Phage-based detection assays have been developed for the detection of viable bacteria for applications in clinical diagnosis, monitoring of water quality, and food safety. The majority of these assays deliver a positive readout in the form of newly generated progeny phages by the bacterial host of interest. Progeny phages are often visualized as plaques, or holes, in a lawn of bacteria on an agar-filled Petri dish; however, this rate-limiting step requires up to 12 h of incubation time. We have previously described an amplification of bacteriophages M13 inside droplets of media suspended in perfluorinated oil; a single phage M13 in a droplet yields 10(7) copies in 3-4 h. Here, we describe that encapsulation of reporter phages, both lytic T4-LacZ and nonlytic M13, in monodisperse droplets can also be used for rapid enumeration of phage. Compartmentalization in droplets accelerated the development of the signal from the reporter enzyme; counting of "positive" droplets yields accurate enumeration of phage particles ranging from 10(2) to 10(6) pfu/mL. For enumeration of T4-LacZ phage, the fluorescent signal appeared in as little as 90 min. Unlike bulk assays, quantification in emulsion is robust and insensitive to fluctuations in environmental conditions (e.g., temperature). Power-free emulsification using gravity-driven flow in the absence of syringe pumps and portable fluorescence imaging solutions makes this technology promising for use at the point of care in low-resource environments. This droplet-based phage enumeration method could accelerate and simplify point-of-care detection of the pathogens for which reporter bacteriophages have been developed.

  18. Flocculation of protein-stabilized oil-in-water emulsions.

    PubMed

    Dickinson, Eric

    2010-11-01

    The flocculation properties of oil-in-water emulsions stabilized by proteins are reviewed from the colloid science perspective. Emphasis is placed on insight from systematic studies of the stability of emulsions prepared with a milk protein ingredient as the sole emulsifying agent. The main factors considered are pH, ionic strength, calcium ion concentration, thermal processing, and the presence of cosolutes (alcohol, sugars). Contrasting dependences of the flocculation behaviour on these factors are observed for the pH-sensitive disordered caseins (alpha(s1)-casein or beta-casein) and the heat-sensitive globular proteins (especially beta-lactoglobulin). In comparing characteristic emulsion properties obtained with different proteins, we consider the relative importance of the different kinds of molecular and colloidal interactions-electrostatic, steric, hydrophobic and covalent.

  19. Emulsion liquid membrane for textile dye removal: Stability study

    NASA Astrophysics Data System (ADS)

    Kusumastuti, Adhi; Syamwil, Rodia; Anis, Samsudin

    2017-03-01

    Although textile dyes is basically available in very low concentration; it should be removed due to the toxicity to human body and environment. Among the existing methods, emulsion liquid membrane (ELM) is a promising method by providing high interfacial area and the ability to remove a very low concentration of the solute. The optimal emulsions were produced using commercially supplied homogeniser. The drop size was measured by the aid of microscope and image J software. Initially, methylene blue in simulated wastewater was extracted using a stirrer. Methylene blue concentration was determined using spectrophotometer. The research obtained optimal emulsion at surfactant concentration of 4 wt. %, kerosene as diluent, emulsification time of 30 min, emulsification speed of 2000 rpm. The lowest membrane breakage and the longest stability time were about 0.11% and 150 min, respectively.

  20. Processable high internal phase Pickering emulsions using depletion attraction

    NASA Astrophysics Data System (ADS)

    Kim, Kyuhan; Kim, Subeen; Ryu, Jiheun; Jeon, Jiyoon; Jang, Se Gyu; Kim, Hyunjun; Gweon, Dae-Gab; Im, Won Bin; Han, Yosep; Kim, Hyunjung; Choi, Siyoung Q.

    2017-02-01

    High internal phase emulsions have been widely used as templates for various porous materials, but special strategies are required to form, in particular, particle-covered ones that have been more difficult to obtain. Here, we report a versatile strategy to produce a stable high internal phase Pickering emulsion by exploiting a depletion interaction between an emulsion droplet and a particle using water-soluble polymers as a depletant. This attractive interaction facilitating the adsorption of particles onto the droplet interface and simultaneously suppressing desorption once adsorbed. This technique can be universally applied to nearly any kind of particle to stabilize an interface with the help of various non- or weakly adsorbing polymers as a depletant, which can be solidified to provide porous materials for many applications.

  1. Synthesis of Fluorosurfactants for Emulsion-Based Biological Applications

    PubMed Central

    2015-01-01

    Microemulsion represents an attractive platform for fundamental and applied biomedical research because the emulsified droplets can serve as millions of compartmentalized micrometer-sized reactors amenable to high-throughput screening or online monitoring. However, establishing stable emulsions with surfactants that are compatible with biological applications remains a significant challenge. Motivated by the lack of commercially available surfactants suitable for microemulsion-based biological assays, this study describes the facile synthesis of a biocompatible fluorosurfactant with nonionic tris(hydroxymethyl)methyl (Tris) polar head groups. We have further demonstrated compatibility of the developed surfactant with diverse emulsion-based applications, including DNA polymeric nanoparticle synthesis, enzymatic activity assay, and bacterial or mammalian cell culture, in the setup of both double- and multiphases of emulsions. PMID:24646088

  2. Sensitivities of droplet size and stability in monomeric emulsions

    SciTech Connect

    Fontenot, K.; Schork, F.J. )

    1993-02-01

    The stability of a monomeric emulsion is directly dependent on the size of the monomer droplets. The droplet diameter is in turn significantly influenced by a variety of parameters. Both size and stability are important when emulsions consisting of small droplets are polymerized. These parameters were studied for the monomer methyl methacrylate, although the monomers styrene and vinyl acetate were also considered. Conductance was developed as a predictive tool for providing a measurement of emulsion stability. These indications were verified by shelf life stabilities and droplet size measurements. The key parameters which affect size and stability were found to be cosurfactant concentration and monomer water solubility. Coalescence was found to play an important role in stability as well.

  3. Automated Track Recognition and Event Reconstruction in Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

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

    1998-01-01

    The major advantages of nuclear emulsion for detecting charged particles are its submicron position resolution and sensitivity to minimum ionizing particles. These must be balanced, however, against the difficult manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyze the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject back- ground and estimate error rates. The system has been used to analyze a sample of high-multiplicity Pb-Pb interactions (charged particle multiplicities approx. 1100) produced by the 158 GeV/c per nucleon Pb-208 beam at CERN. Automatically reconstructed track lists agree with our best manual measurements to 3%. We describe the image analysis and track reconstruction techniques, and discuss the measurement and reconstruction uncertainties.

  4. Processable high internal phase Pickering emulsions using depletion attraction

    PubMed Central

    Kim, KyuHan; Kim, Subeen; Ryu, Jiheun; Jeon, Jiyoon; Jang, Se Gyu; Kim, Hyunjun; Gweon, Dae-Gab; Im, Won Bin; Han, Yosep; Kim, Hyunjung; Choi, Siyoung Q.

    2017-01-01

    High internal phase emulsions have been widely used as templates for various porous materials, but special strategies are required to form, in particular, particle-covered ones that have been more difficult to obtain. Here, we report a versatile strategy to produce a stable high internal phase Pickering emulsion by exploiting a depletion interaction between an emulsion droplet and a particle using water-soluble polymers as a depletant. This attractive interaction facilitating the adsorption of particles onto the droplet interface and simultaneously suppressing desorption once adsorbed. This technique can be universally applied to nearly any kind of particle to stabilize an interface with the help of various non- or weakly adsorbing polymers as a depletant, which can be solidified to provide porous materials for many applications. PMID:28145435

  5. Destabilising Pickering emulsions by drop flocculation and adhesion.

    PubMed

    Whitby, Catherine P; Khairul Anwar, Hunainah; Hughes, James

    2016-03-01

    We have investigated how emulsions of water drops coated by organoclay particles destabilise in organic solvents. The drops destabilise and the emulsions undergo a fluid-solid transition if the particles are poorly wetted by the solvent. We show that the drops adhere together and form three-dimensional networks as the fraction of the poor-quality solvent in the mixture increases. Microscopic observations revealed that the drops coalesce into buckled, non-spherical shapes in mixtures rich in poor-quality solvent. A key finding is that destabilisation is favoured under conditions where the energy of adhesion between the particle layers coating drops is comparable to the energy required to detach the particles from the drops. Rupture of the interfacial layer produces particle flocs and uncoated, unstable water drops that settle out of the emulsion.

  6. Electrochemical Stimulated Pickering Emulsion for Recycling of Enzyme in Biocatalysis.

    PubMed

    Peng, Liao; Feng, Anchao; Liu, Senyang; Huo, Meng; Fang, Tommy; Wang, Ke; Wei, Yen; Wang, Xiaosong; Yuan, Jinying

    2016-11-02

    Potential-stimulated Pickering emulsions, using electrochemical responsive microgels as particle stabilizers, are prepared and used for biocatalysis. The microgels are constructed from cyclodextrin functionalized 8-arm poly(ethylene glycol) (8A PEG-CD) and ferrocene modified counterparts (8A PEG-Fc) via CD/Fc host-guest chemistry. Taking advantage of the redox reaction of Fc, the formation and deformation of the microgels and corresponding Pickering emulsions can be reversibly stimulated by external potential, and have been used for the hydrolysis of triacetin and kinetic resolution reaction of (R,S)-1-phenylethanol catalyzed by lipases. Potential stimulated destabilization of the emulsion realizes an effective separation of the products and enzyme recycling.

  7. Spectra, composition, and interactions of nuclei with magnet interaction chambers

    NASA Technical Reports Server (NTRS)

    Parneil, T. A.; Derrickson, J. H.; Fountain, W. F.; Roberts, F. E.; Tabuki, T.; Watts, J. W.; Burnett, T. H.; Cherry, M. C.; Dake, S.; Fuki, M.

    1990-01-01

    Emulsion chambers will be flown in the Astromag Facility to measure the cosmic ray composition and spectra to 10 exp 15 eV total energy and to definitively study the characteristics of nucleus-nucleus interactions above 10 exp 12 eV/n. Two configurations of emulsion chambers will be flown in the SCIN/MAGIC experiment. One chamber has an emulsion target and a calorimeter similar to those recently flown on balloons for composition and spectra measurements. The other has an identical calorimeter and a low-density target section optimized for performing rigidity measurements on charged particles produced in interactions. The transverse momenta of charged and neutral mesons, direct hadronic pairs from resonance decays and interference effects, and possible charge clustering in high-density states of matter will be studied.

  8. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

  10. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable to...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable...

  12. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable to...

  13. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb rubber...

  14. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb...

  15. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb...

  16. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb...

  17. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb rubber...

  18. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... drawing with emulsions or soaps subcategory. 467.60 Section 467.60 Protection of Environment ENVIRONMENTAL... Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability; description of the drawing with emulsions or soaps subcategory. This subpart applies to discharges of pollutants to waters of the...

  19. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... drawing with emulsions or soaps subcategory. 467.60 Section 467.60 Protection of Environment ENVIRONMENTAL... CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability; description of the drawing with emulsions or soaps subcategory. This subpart applies to discharges of pollutants to waters of...

  20. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... drawing with emulsions or soaps subcategory. 467.60 Section 467.60 Protection of Environment ENVIRONMENTAL... Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability; description of the drawing with emulsions or soaps subcategory. This subpart applies to discharges of pollutants to waters of the...

  1. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... drawing with emulsions or soaps subcategory. 467.60 Section 467.60 Protection of Environment ENVIRONMENTAL... CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability; description of the drawing with emulsions or soaps subcategory. This subpart applies to discharges of pollutants to waters of...

  2. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... drawing with emulsions or soaps subcategory. 467.60 Section 467.60 Protection of Environment ENVIRONMENTAL... CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability; description of the drawing with emulsions or soaps subcategory. This subpart applies to discharges of pollutants to waters of...

  3. Evaporation of Particle-Stabilized Emulsion Sunscreen Films.

    PubMed

    Binks, Bernard P; Fletcher, Paul D I; Johnson, Andrew J; Marinopoulos, Ioannis; Crowther, Jonathan M; Thompson, Michael A

    2016-08-24

    We recently showed (Binks et al., ACS Appl. Mater. Interfaces, 2016, DOI: 10.1021/acsami.6b02696) how evaporation of sunscreen films consisting of solutions of molecular UV filters leads to loss of UV light absorption and derived sun protection factor (SPF). In the present work, we investigate evaporation-induced effects for sunscreen films consisting of particle-stabilized emulsions containing a dissolved UV filter. The emulsions contained either droplets of propylene glycol (PG) in squalane (SQ), droplets of SQ in PG or droplets of decane in PG. In these different emulsion types, the SQ is involatile and shows no evaporation, the PG is volatile and evaporates relatively slowly, whereas the decane is relatively very volatile and evaporates quickly. We have measured the film mass and area, optical micrographs of the film structure, and the UV absorbance spectra during evaporation. For emulsion films containing the involatile SQ, evaporation of the PG causes collapse of the emulsion structure with some loss of specular UV absorbance due to light scattering. However, for these emulsions with droplets much larger than the wavelength of light, the light is scattered only at small forward angles so does not contribute to the diffuse absorbance and the film SPF. The UV filter remains soluble throughout the evaporation and thus the UV absorption by the filter and the SPF remain approximately constant. Both PG-in-SQ and SQ-in-PG films behave similarly and do not show area shrinkage by dewetting. In contrast, the decane-in-PG film shows rapid evaporative loss of the decane, followed by slower loss of the PG resulting in precipitation of the UV filter and film area shrinkage by dewetting which cause the UV absorbance and derived SPF to decrease. Measured UV spectra during evaporation are in reasonable agreement with spectra calculated using models discussed here.

  4. Lipid composition and structure of commercial parenteral emulsions.

    PubMed

    Férézou, J; Nguyen, T L; Leray, C; Hajri, T; Frey, A; Cabaret, Y; Courtieu, J; Lutton, C; Bach, A C

    1994-07-14

    In order to study the influence of the phospholipid/triacylglycerol (PL/TG) ratio of parenteral emulsions on the distribution and the physico-chemical properties of their fat particles, commercial 10, 20 or 30% fat formulas were fractionated by centrifugation into an upper lipid cake (resuspended in aqueous glycerol) and a subnatant or mesophase, from which a PL-rich subfraction (d = 1.010-1.030 g/l) was purified by density gradient ultracentrifugation. Chemical and 31P-NMR analyses of these fractions indicated that at least two types of fat particles coexist in parenteral emulsions: (i) TG-rich particles (mean diameter: 330, 400, 470 nm in the 10, 20, 30% emulsion) which contain practically all the TG and esterified phytosterols of native emulsions, but only a fraction of their PL, unesterified cholesterol and phytosterols, and other minor lipids; (ii) PL-bilayer particles or liposomes (mean diameter: 80-100 nm) which are constituted with the remaining PL and relatively very small amounts of TG and other lipids. The higher the oil content of the emulsion, the lower the amount of these PL-rich particles, which represent the major particle population of the mesophase. Indeed, minute amounts of TG-rich particles (probably the smallest ones) are also present in the mesophase, even in the PL-rich subfraction which contains the bulk of liposomal PL. Since the PL-rich particles of the infused emulsion generate lipoprotein X-like particles, only the large TG-rich particles can be considered as true chylomicron counterparts.

  5. Albedo in the ATIC Experiment

    NASA Technical Reports Server (NTRS)

    Sokolskaya, N. V.; Adams, J. H., Jr.; Ahn, H. S.; Bashindzhagyan, G. L.; Batkov, K. E.; Case, G.; Christl, M.; Chang, J.; Fazely, A. R.; Ganel, O.; Six, N. Frank (Technical Monitor)

    2002-01-01

    ATIC(Advanced Thin Ionization Calorimeter) is a balloon borne experiment designed to measure the cosmic ray composition for elements from hydrogen to iron and their energy spectra from approx.50 GeV to near 100 TeV. It consists of a Si-matrix detector to determine the charge of a CR particle, a scintillator hodoscope for tracking, carbon interaction targets and a fully active BGO calorimeter. ATIC had its first 16-day flight from McMurdo, Antarctica from 28/12/2000 to 13/01/2000. The ATIC flight collected approximately 25 million events. To measure charge of primary particle in presence of radiation scattered back from the interaction and subsequent shower development in the calorimeter a charge detector must be a mosaic of small detector pads so that the pad containing the signal from the incident particle has no additional signal from albedo particles. Therefore the silicon matrix was built of 4480 individual silicon pads each 2 cm x 1.5 cm. The matrix consists of four planes of detectors and the active detector area, in these planes are partially overlapped to completely cover the aperture. The lateral and amplitude distributions of albedo signals in Si-matrix are analyzed for different primary nuclei and different energy deposits in BGO calorimeter. The greater part of albedo signals has Q near 1, where Q = square root of Amplitude(MIP). The albedo distribution exponentially decreases up to Q near 8. These high values are produced by slow protons and plans. There are also a small number of signals of Q > 8, mainly for heavy nucleus primaries. These signals are apparently generated by neutrons. The comparison of the experimental data and simulations with GEANT 3-21 code using QGSM generator for nucleus-nucleus interactions is presented.

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

    NASA Astrophysics Data System (ADS)

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

    2008-11-01

    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, τ˜CR≡(τCRR/σ)≈0.40 , which is independent of surfactant used, solution viscosity, and bubble volume fraction (varied between 92 and 98 %). Here τCR is the dimensional shear stress, above which a bubble with radius R and surface tension σ would break in sheared foam. The value of the critical stress experimentally found by us τ˜CR≈0.40 , is about two orders of magnitude lower than the critical stress for breakup of single bubbles in sheared Newtonian liquids, τ˜CR≈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% ⩽Φ⩽95% to study drop breakup in concentrated emulsions. Qualitatively similar behavior was observed to that of foams, with the critical dimensionless stress for drop breakup being lower, τ˜CR≈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

  7. Rapid and medium setting high float bituminous emulsions

    SciTech Connect

    Schilling, P.; Schreuders, H.G.

    1987-06-30

    This patent describes a rapid set high float aqueous bituminous emulsion-comprising bitumen, water, and from about 0.4% to about 0.6%, based on the weight of the emulsion, of an anionic emulsifier comprised of an alkaline solution of a combination of (1) 20% to 80% fatty acids selected from the group consisting of tall oil fatty acids, tallow fatty acids, and mixtures. (2) 20% to 80% of a product of the reaction of the fatty acids with a member of the group consists of acrylic acid, methacrylic acid, fumaric acid, and maleic anhydride.

  8. Conditioning in laser skin resurfacing - betulin emulsion and skin recovery.

    PubMed

    Metelmann, Hans-Robert; Podmelle, Fred; Waite, Peter D; Müller-Debus, Charlotte Friederieke; Hammes, Stefan; Funk, Wolfgang

    2013-04-01

    Laser skin resurfacing of the face by CO₂-laser ablation is causing superficial wounds that need rapid recovery to reduce the risk of infection, the risk of chronification and as a result the risk of unaesthetic scars. The question being addressed by this study is to demonstrate benefit of betulin emulsion skin care after CO₂-laser wounds. The outcome of this aesthetic comparison between betulin emulsion, moist wound dressing and gauze covering in promoting the recovery process in laser skin ablation is to demonstrate improved aesthetic benefit for the patient.

  9. Preparation of Fine Oxide Powders by Emulsion Precipitation.

    DTIC Science & Technology

    1987-05-31

    anionic and non-ionic commercial emulsifying agents were tried, including Aerosol-OT, Arlacel 83, Span 60, Span 80, Tween 80 , Tween 85, Pluronic L62 and...w/o type emulsion with all three organic liquids, while other o/w or w/o type emulsions are produced by Tween 80 and Tween 85, depending upon the...of 72 v/o toluene; aqueous 25 v/o 0.4M Y(N03 )3 and 3 v/o * emulsifier (1.6 Span 60 + 1.4 Tween 80 ), which was stirred for 15 minutes with a magnetic

  10. Statistical physics of topological emulsions and expanding populations

    NASA Astrophysics Data System (ADS)

    Korolev, Kirill Sergeevich

    This thesis studies how microscopic interactions lead to large scale phenomena in two very different systems: two-dimensional liquid crystals and expanding populations. First, we explore the interactions among circular droplets embedded in a two-dimensional liquid crystal. The interactions arise due to anchoring boundary conditions on the surface of the inclusions and the elastic deformations of the orientational order parameter in the continuous phase. We analytically compute the texture around a single droplet and the far-field droplet-droplet pair potential. The near-field pair potential is computed numerically. We find that droplets attract at long separations and repel at short separations, which results in a well-defined preferred distance between the droplets and stabilization of the emulsion. Self-organization, barriers to coalescence, and the effects of thermal fluctuations are also discussed. Second, we study the role of randomness in the number of offspring on the evolutionary dynamics of expanding populations. Several equally fit genetic variants (alleles) are considered. We find that spatial expansion combined with demographic fluctuations leads to a substantial loss of genetic diversity and spatial segregation of the alleles. The effects of these processes on recurring mutations and selective sweeps are studied as well. Third, the competition between two alleles of different fitness is investigated. We find that the essential features of this competition can be captured by a non-linear reaction-diffusion equation. During a range expansion the fitter allele forms growing sectors that eventually engulf the less fit allele. The applications to measuring relative fitness in microbiological experiments are discussed. Finally, we analyze how a combination of strong stochasticity and weak competition affects the spreading of beneficial mutations in stationary, non-expanding, populations.

  11. Tribology of steel/steel interaction in oil-in-water emulsion; a rationale for lubricity.

    PubMed

    Kumar, Deepak; Daniel, Jency; Biswas, S K

    2010-05-15

    Oil droplets are dispersed in water by an anionic surfactant to form an emulsion. The lubricity of this emulsion in steel/steel interaction is explored in a ball on flat nanotribometer. The droplet size and charge are measured using dynamic light scattering, while the substrate charge density is estimated using the pH titration method. These data are combined to calculate the DLVO forces for the droplets generated for a range of surfactant concentration and two oil to water volume ratios. The droplets have a clear bi-modal size distribution. The study shows that the smaller droplets which experience weak repulsion are situated (at the highest DLVO barrier) much closer to the substrate than the bigger droplets, which experience the same DLVO force, are. We suggest that the smaller droplets thus play a more important role in lubricity than what the bigger droplets do. The largest volume of such small droplets occurs in the 0.5 mM-1 mM range of surfactant concentration and 1% oil to water volume ratio, where the coefficient of friction is also observed to be the least.

  12. Automatic track following system to study double strangeness nuclei in nuclear emulsion exposed to the observable limit

    NASA Astrophysics Data System (ADS)

    Myint Kyaw Soe; Goto, Ryosuke; Mishina, Akihiro; Nakanisi, Yoshiaki; Nakashima, Daisuke; Yoshida, Junya; Nakazawa, Kazuma

    2017-03-01

    An automatic track following system has been successfully developed to follow tracks in nuclear emulsion sheets exposed with beam up to the limit to be observed for the first time. The track followed rate of the system is 99.5% with the assistance of the new techniques. The working speed for a track is less than 1 min through one thick emulsion sheet, whereas it is 15 times faster than that of semiautomatic system with human. The system working for 24 h is applied for the E07 experiment at J-PARC and makes it possible to detect 102 nuclei with double strangeness (S=-2 nuclei) within one year. Regarding analyses to identify nuclear species of S=-2 nuclei, the system shows quite decent job for significant steps such as following tracks emitted to spherical directions from S=-2 nuclei, measurement of lengths of followed tracks, and so on.

  13. High-throughput screening of microchip-synthesized genes in programmable double-emulsion droplets.

    PubMed

    Chan, H F; Ma, S; Tian, J; Leong, K W

    2017-03-09

    The rapid advances in synthetic biology and biotechnology are increasingly demanding high-throughput screening technology, such as screening of the functionalities of synthetic genes for optimization of protein expression. Compartmentalization of single cells in water-in-oil (W/O) emulsion droplets allows screening of a vast number of individualized assays, and recent advances in automated microfluidic devices further help realize the potential of droplet technology for high-throughput screening. However these single-emulsion droplets are incompatible with aqueous phase analysis and the inner droplet environment cannot easily communicate with the external phase. We present a high-throughput, miniaturized screening platform for microchip-synthesized genes using microfluidics-generated water-in-oil-in-water (W/O/W) double emulsion (DE) droplets that overcome these limitations. Synthetic gene variants of fluorescent proteins are synthesized with a custom-built microarray inkjet synthesizer, which are then screened for expression in Escherichia coli (E. coli) cells. Bacteria bearing individual fluorescent gene variants are encapsulated as single cells into DE droplets where fluorescence signals are enhanced by 100 times within 24 h of proliferation. Enrichment of functionally-correct genes by employing an error correction method is demonstrated by screening DE droplets containing fluorescent clones of bacteria with the red fluorescent protein (rfp) gene. Permeation of isopropyl β-d-1-thiogalactopyranoside (IPTG) through the thin oil layer from the external solution initiates target gene expression. The induced expression of the synthetic fluorescent proteins from at least ∼100 bacteria per droplet generates detectable fluorescence signals to enable fluorescence-activated cell sorting (FACS) of the intact droplets. This technology obviates time- and labor-intensive cell culture typically required in conventional bulk experiment.

  14. The Compressed Baryonic Matter Experiment at FAIR

    NASA Astrophysics Data System (ADS)

    Heuser, J. M.

    2011-04-01

    The Compressed Baryonic Matter (CBM) experiment is being planned at the international research centre FAIR, under realization next to the GSI laboratory in Darmstadt, Germany. Its physics programme addresses the QCD phase diagram in the region of highest net baryon densities. Of particular interest are the expected first order phase transition from partonic to hadronic matter, ending in a critical point, and modifications of hadron properties in the dense medium as a signal of chiral symmetry restoration. Laid out as a fixed-target experiment at the synchrotrons SIS-100/SIS-300, providing magnetic bending power of 100 and 300 T/m, the CBM detector will record both proton-nucleus and nucleus-nucleus collisions at beam energies up to 45A GeV. Hadronic, leptonic and photonic observables have to be measured with large acceptance. The nuclear interaction rates will reach up to 10 MHz to measure extremely rare probes like charm near threshold. Two versions of the experiment are being studied, optimized for either electron-hadron or muon identification, combined with silicon detector based charged-particle tracking and micro-vertex detection. The research programme will start at SIS-100 with ion beams between 2 and 11A GeV, and protons up to energies of 29 GeV using the HADES detector and an initial configuration of the CBM experiment. The CBM physics requires the development of novel detector systems, trigger and data acquisition concepts as well as innovative real-time reconstruction techniques. Progress with feasibility studies of the experiment and the development of its detector systems are discussed.

  15. A Simple Experiment Illustrating the Structure of Association Colloids.

    ERIC Educational Resources Information Center

    Friberg, Stig. E.; Bendiksen, Beverly

    1979-01-01

    The experiment described is intended to illustrate the intermolecular phenomena involved in association colloids. These are normal and inverse micelles and lyotropic liquid crystals. Solubilization, microemulsion and emulsion are discussed. (Author/SA)

  16. DIMENSION STABILIZED FIXED PHOTOGRAPHIC TYPE EMULSION AND A METHOD FOR PRODUCING SAME

    DOEpatents

    Gilbert, F.C.

    1962-03-13

    A process is given for stabilizing the dimensions of fixed gelatin-base photographic type emulsions containing silver halide, and particularly to such emulsions containing large amounts of silver chloride for use as nuclear track emulsions, so that the dimensions of the final product are the same as or in a predetermined fixed ratio to the dimensions of the emulsions prior to exposure. The process comprises contacting an exposed, fixed emulsion with a solution of wood rosin dissolved in ethyl alcohol for times corresponding to the dimensions desired, and thereafter permitting the alcohol to evaporate. (AEC)

  17. Cross-linking of sodium caseinate-structured emulsion with transglutaminase alters postprandial metabolic and appetite responses in healthy young individuals.

    PubMed

    Juvonen, Kristiina R; Macierzanka, Adam; Lille, Martina E; Laaksonen, David E; Mykkänen, Hannu M; Niskanen, Leo K; Pihlajamäki, Jussi; Mäkelä, Kari A; Mills, Clare E N; Mackie, Alan R; Malcolm, Paul; Herzig, Karl-Heinz; Poutanen, Kaisa S; Karhunen, Leila J

    2015-08-14

    The physico-chemical and interfacial properties of fat emulsions influence lipid digestion and may affect postprandial responses. The aim of the present study was to determine the effects of the modification of the interfacial layer of a fat emulsion by cross-linking on postprandial metabolic and appetite responses. A total of fifteen healthy individuals (26.5 (sem 6.9) years and BMI 21.9 (sem 2.0) kg/m2) participated in a cross-over design experiment in which they consumed two isoenergetic (1924 kJ (460 kcal)) and isovolumic (250 g) emulsions stabilised with either sodium caseinate (Cas) or transglutaminase-cross-linked sodium caseinate (Cas-TG) in a randomised order. Blood samples were collected from the individuals at baseline and for 6 h postprandially for the determination of serum TAG and plasma NEFA, cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), glucose and insulin responses. Appetite was assessed using visual analogue scales. Postprandial TAG and NEFA responses and gastric emptying (GE) rates were comparable between the emulsions. CCK increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0.05), while GLP-1 responses did not differ between the two test emulsions. Glucose and insulin profiles were lower after consuming Cas-TG than after consuming Cas (P< 0.05). The overall insulin, glucose and CCK responses, expressed as areas above/under the curve, did not differ significantly between the Cas and Cas-TG meal conditions. Satiety ratings were reduced and hunger, desire to eat and thirst ratings increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0.05). The present results suggest that even a subtle structural modification of the interfacial layer of a fat emulsion can alter the early postprandial profiles of glucose, insulin, CCK, appetite and satiety through decreased protein digestion without affecting significantly on GE or overall lipid digestion.

  18. Fluoropolymer-Based Emulsions for the Intravenous Delivery of Sevoflurane

    PubMed Central

    Fast, Jonathan P.; Perkins, Mark G.; Pearce, Robert A.; Waters, Ralph M.; Mecozzi, Sandro

    2009-01-01

    Background The intravenous delivery of halogenated volatile anesthetics has been previously achieved using phospholipid-stabilized emulsions, e.g. Intralipid. However, fluorinated volatile anesthetics, such as sevoflurane, are partially fluorophilic and do not mix well with classic non-fluorinated lipids. This effect limits the maximum amount of sevoflurane that can be stably emulsified in Intralipid to 3.5% v/v. This is a significant limitation to the potential clinical use of Intralipid-based emulsions. Methods The authors prepared a 20% v/v sevoflurane emulsion using a novel fluorinated surfactant and tested its effectiveness and therapeutic index by administering it to male Sprague-Dawley rats via intravenous injection into the jugular vein. The median effective dose to induce anesthesia (ED50), median lethal dose (LD50), and therapeutic index (LD50 / ED50) were determined. Anesthesia was measured by loss of the forepaw righting reflex. Results The ED50 and LD50 values were found to be 0.41 and 1.05 mL emulsion / kg body weight, respectively. These lead to a therapeutic index of 2.6, which compares favorably to previously determined values of emulsified isoflurane, as well as values for propofol and thiopental. Conclusions A novel semi-fluorinated surfactant was able to considerably increase the maximum amount of stably emulsified sevoflurane compared to Intralipid. These formulations can be used to rapidly induce anesthesia with bolus dosing from which recovery is smooth and rapid. PMID:18813044

  19. Emulsion forming drug delivery system for lipophilic drugs.

    PubMed

    Wadhwa, Jyoti; Nair, Anroop; Kumria, Rachna

    2012-01-01

    In the recent years, there is a growing interest in the lipid-based formulations for delivery of lipophilic drugs. Due to their potential as therapeutic agents, preferably these lipid soluble drugs are incorporated into inert lipid carriers such as oils, surfactant dispersions, emulsions, liposomes etc. Among them, emulsion forming drug delivery systems appear to be a unique and industrially feasible approach to overcome the problem of low oral bioavailability associated with the BCS class II drugs. Self-emulsifying formulations are ideally isotropic mixtures of oils, surfactants and co-solvents that emulsify to form fine oil in water emulsions when introduced in aqueous media. Fine oil droplets would pass rapidly from stomach and promote wide distribution of drug throughout the GI tract, thereby overcome the slow dissolution step typically observed with solid dosage forms. Recent advances in drug carrier technologies have promulgated the development of novel drug carriers such as control release self-emulsifying pellets, microspheres, tablets, capsules etc. that have boosted the use of "self-emulsification" in drug delivery. This article reviews the different types of formulations and excipients used in emulsion forming drug delivery system to enhance the bioavailability of lipophilic drugs.

  20. Mannan-stabilized oil-in-water beverage emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The stabilizing effect of spruce galactoglucomannan (GGM) on a model beverage emulsion system was studied and compared to that of guar gum and locust bean gum galactomannans, konjac glucomannan, and corn arabinoxylan. In addition, enzymatic modification was applied on guar gum to examine the effect ...

  1. Modular 'click-in-emulsion' bone-targeted nanogels.

    PubMed

    Heller, Daniel A; Levi, Yair; Pelet, Jeisa M; Doloff, Joshua C; Wallas, Jasmine; Pratt, George W; Jiang, Shan; Sahay, Gaurav; Schroeder, Avi; Schroeder, Josh E; Chyan, Yieu; Zurenko, Christopher; Querbes, William; Manzano, Miguel; Kohane, Daniel S; Langer, Robert; Anderson, Daniel G

    2013-03-13

    A new class of nanogel demonstrates modular biodistribution and affinity for bone. Nanogels, ∼70 nm in diameter and synthesized via an astoichiometric click-chemistry in-emulsion method, controllably display residual, free clickable functional groups. Functionalization with a bisphosphonate ligand results in significant binding to bone on the inner walls of marrow cavities, liver avoidance, and anti-osteoporotic effects.

  2. Transdermal delivery of forskolin from emulsions differing in droplet size.

    PubMed

    Sikora, Elżbieta; Llinas, Meritxell; Garcia-Celma, Maria Jose; Escribano, Elvira; Solans, Conxita

    2015-02-01

    The skin permeation of forskolin, a diterpene isolated from Coleus forsholii, was studied using oil in water (O/W) emulsions as delivery formulations and also an oil solution for comparative purposes. Two forskolin-loaded emulsions of water/Brij 72:Symperonic A7/Miglyol 812:Isohexadecane, at 0.075 wt% forskolin concentration were prepared with the same composition and only differing in droplet size (0.38 μm and 10 μm). The emulsions showed high kinetic stability at 25 °C. In vitro study of forskolin penetration through human skin was carried out using the MicroettePlus(®) system. The concentration of the active in the receptor solution (i.e. ethanol/phosphate buffer 40/60, v/v) was analyzed by high performance liquid chromatography with UV detection. The obtained results showed that forskolin permeation from the emulsions and the oil solution, through human skin, was very high (up to 72.10%), and no effect of droplet size was observed.

  3. Proton Linear Energy Transfer measurement using Emulsion Cloud Chamber

    NASA Astrophysics Data System (ADS)

    Shin, Jae-ik; Park, Seyjoon; Kim, Haksoo; Kim, Meyoung; Jeong, Chiyoung; Cho, Sungkoo; Lim, Young Kyung; Shin, Dongho; Lee, Se Byeong; Morishima, Kunihiro; Naganawa, Naotaka; Sato, Osamu; Kwak, Jungwon; Kim, Sung Hyun; Cho, Jung Sook; Ahn, Jung Keun; Kim, Ji Hyun; Yoon, Chun Sil; Incerti, Sebastien

    2015-04-01

    This study proposes to determine the correlation between the Volume Pulse Height (VPH) measured by nuclear emulsion and Linear Energy Transfer (LET) calculated by Monte Carlo simulation based on Geant4. The nuclear emulsion was irradiated at the National Cancer Center (NCC) with a therapeutic proton beam and was installed at 5.2 m distance from the beam nozzle structure with various thicknesses of water-equivalent material (PMMA) blocks to position with specific positions along the Bragg curve. After the beam exposure and development of the emulsion films, the films were scanned by S-UTS developed in Nagoya University. The proton tracks in the scanned films were reconstructed using the 'NETSCAN' method. Through this procedure, the VPH can be derived from each reconstructed proton track at each position along the Bragg curve. The VPH value indicates the magnitude of energy loss in proton track. By comparison with the simulation results obtained using Geant4, we found the correlation between the LET calculated by Monte Carlo simulation and the VPH measured by the nuclear emulsion.

  4. Influence of olive oil emulsions on dentin demineralization in vitro.

    PubMed

    Buchalla, W; Attin, T; Roth, P; Hellwig, E

    2003-01-01

    The effect of two different concentrations of olive oil emulsions on development of artificial caries-like dentin lesions under severe demineralizing conditions was investigated. Bovine dentin samples (n = 180) were ground flat, polished, divided into four groups, and subjected to three demineralization cycles per day. Samples were stored in one of the following solutions for 5 min prior to demineralization in a buffer solution (pH 5): Group 1: 50% oil emulsion (olive oil and distilled water); group 2: 5% oil emulsion; group 3: distilled water; and group 4: 1,500 ppm sodium fluoride. Daily up to 9 days, lesion depth (ld) and mineral loss (deltaZ) were determined by means of microradiography and analyzed by ANOVA and Tukey's studentized range test (p < or = 0.05). Lesion depth increased with time for all groups. Mineral loss increased in groups 1-3. A small but significant decrease in mineral loss was observed following treatment with lipid emulsions as compared to treatment with distilled water, but fluoride treatment was considerably more effective. Mean mineral loss (means +/- SD in vol% x microm) averaged over the study period was 4,368 +/- 1,599, 4,536 +/- 1,823, 4,849 +/- 1,798, and 789 +/- 177 for group 1, 2, 3, and 4, respectively. Ratio (deltaZ/ld) remained constant around 30 vol% for groups 1-3, but decreased for group 4. In conclusion, externally provided lipids have the potential to reduce dentin demineralization in vitro.

  5. Morphological transformations of native petroleum emulsions. I. Viscosity studies.

    PubMed

    Evdokimov, Igor N; Efimov, Yaroslav O; Losev, Aleksandr P; Novikov, Mikhail A

    2008-07-15

    Emulsions of water in as-recovered native crude oils of diverse geographical origin evidently possess some common morphological features. At low volume fractions varphi of water, the viscosity behavior of emulsions is governed by the presence of flocculated clusters of water droplets, whereas characteristic tight gels, composed of visually monodisperse small droplets, are responsible for the viscosity anomaly at varphi approximately 0.4-0.5. Once formed, small-droplet gel domains apparently retain their structural integrity at higher varphi, incorporating/stabilizing new portions of water as larger-sized droplets. The maximum hold-up of disperse water evidently is the close-packing limit of varphi approximately 0.74. At higher water contents (up to varphi approximately 0.83), no inversion to O/W morphology takes place, but additional water emerges as a separate phase. The onset of stratified flow (W/O emulsion gel + free water) is the cause of the observed viscosity decrease, contrary to the conventional interpretation of the viscosity maximum as a reliable indicator of the emulsion inversion point.

  6. Influence of droplet charge on the chemical stability of citral in oil-in-water emulsions.

    PubMed

    Choi, Seung Jun; Decker, Eric Andrew; Henson, Lulu; Popplewell, L Michael; McClements, David Julian

    2010-08-01

    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.

  7. Enhanced stabilization of cloudy emulsions with gum Arabic and whey protein isolate.

    PubMed

    Klein, Miri; Aserin, Abraham; Svitov, Inna; Garti, Nissim

    2010-05-01

    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.

  8. Characteristics of meat emulsion systems as influenced by different levels of lemon albedo.

    PubMed

    Sarıçoban, C; Ozalp, B; Yılmaz, M T; Ozen, G; Karakaya, M; Akbulut, M

    2008-11-01

    The effect of the addition of lemon albedo on the functional properties of emulsions was studied by using a model system. Oil/water (O/W) model emulsion systems were prepared by the addition of two types of lemon albedo (raw and dehydrated) at five concentrations (0.0%, 2.5%, 5.0%, 7.5% and 10%) to mechanically deboned chicken meat. The emulsion capacity, stability, viscosity and flow properties of the prepared model emulsions were analyzed. In addition, the colour parameters of cooked emulsion gel were determined. The addition of lemon albedo increased the emulsion capacity (EC) and the highest EC value was reached with 5% of albedo added. However, further increase in the albedo concentration caused an inverse trend in the EC values. A similar trend was observed in the emulsion stability (ES) values. Dehydrated albedo (DA) addition caused higher EC and ES values than did raw albedo (RA). DA increased the L(∗), a(∗) and b(∗) values of the cooked emulsion gels. Emulsion viscosity (EV) values were positively correlated with an increase in albedo concentration and the highest EV value was obtained from the emulsions with 10% albedo. Albedo addition did not change the flow properties of the emulsions and, in addition, increased the pseudoplasticity. As a consequence, the use of lemon albedo might be a potential dietary fiber source to enhance the functional and technological properties for frankfurter-type meat products.

  9. The influence of emulsion structure on the Maillard reaction of ghee.

    PubMed

    Newton, Angela E; Fairbanks, Antony J; Golding, Matt; Andrewes, Paul; Gerrard, Juliet A

    2015-04-15

    Food systems, such as cream and butter, have an emulsion or emulsion-like structure. When these food emulsions are heated to high temperatures to make products such as ghee, the Maillard reaction forms a range of volatile flavour compounds. The objective of this paper was to unravel the specific influence of emulsion structure on the Maillard reaction pathways that occur during the cooking of ghee using model systems. Switching the dispersed phase from oil to water provided a means of altering the ratios of volatile compounds produced in the cooked samples. The oil-in-water emulsion generated a volatile compound profile similar to that of the fat containing two phase model matrix, whereas the water-in-oil emulsion produced a different ratio of these compounds. The ability to generate different volatile compound profiles through the use of inverted emulsion structures could point to a new avenue for control of the Maillard reaction in high temperature food systems.

  10. Oil-in-water emulsions stabilised by cellulose ethers: stability, structure and in vitro digestion.

    PubMed

    Borreani, Jennifer; Espert, María; Salvador, Ana; Sanz, Teresa; Quiles, Amparo; Hernando, Isabel

    2017-03-09

    The effect of cellulose ethers in oil-in-water emulsions on stability during storage and on texture, microstructure and lipid digestibility during in vitro gastrointestinal digestion was investigated. All the cellulose ether emulsions showed good physical and oxidative stability during storage. In particular, the methylcellulose with high methoxyl substituents (HMC) made it possible to obtain emulsions with high consistency which remained almost unchanged during gastric digestion, and thus could enhance fullness and satiety perceptions at gastric level. Moreover, the HMC emulsion slowed down lipid digestion to a greater extent than a conventional protein emulsion or the emulsions stabilised by the other cellulose ethers. Therefore, HMC emulsions could be used in weight management to increase satiation capacity and decrease lipid digestion.

  11. Non-coalescence of oppositely charged droplets in pH-sensitive emulsions

    PubMed Central

    Liu, Tingting; Seiffert, Sebastian; Thiele, Julian; Abate, Adam R.; Weitz, David A.; Richtering, Walter

    2012-01-01

    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. PMID:22203968

  12. Preparation of uniform particle-stabilized emulsions using SPG membrane emulsification.

    PubMed

    Sun, Guanqing; Qi, Feng; Wu, Jie; Ma, Guanghui; Ngai, To

    2014-06-24

    Various aspects of particle-stabilized emulsions (or so-called Pickering emulsions) have been extensively investigated during the last two decades, but the preparation of uniform Pickering emulsion droplets via a simple and scalable method has been sparingly realized. We report the preparation of uniform Pickering emulsions by Shirasu porous glass (SPG) membrane emulsification. The size of the emulsion droplets ranging from 10-50 μm can be precisely controlled by the size of the membrane pore. The emulsion droplets have a high monodispersity with coefficients of variation (CV) lower than 15% in all of the investigated systems. We further demonstrate the feasibility of locking the assembled particles at the interface, and emulsion droplets have been shown to be excellent templates for the preparation of monodisperse colloidosomes that are necessary in drug-delivery systems.

  13. Lipid emulsions – Guidelines on Parenteral Nutrition, Chapter 6

    PubMed Central

    Adolph, M.; Heller, A. R.; Koch, T.; Koletzko, B.; Kreymann, K. G.; Krohn, K.; Pscheidl, E.; Senkal, M.

    2009-01-01

    The infusion of lipid emulsions allows a high energy supply, facilitates the prevention of high glucose infusion rates and is indispensable for the supply with essential fatty acids. The administration of lipid emulsions is recommended within ≤7 days after starting PN (parenteral nutrition) to avoid deficiency of essential fatty acids. Low-fat PN with a high glucose intake increases the risk of hyperglycaemia. In parenterally fed patients with a tendency to hyperglycaemia, an increase in the lipid-glucose ratio should be considered. In critically ill patients the glucose infusion should not exceed 50% of energy intake. The use of lipid emulsions with a low phospholipid/triglyceride ratio is recommended and should be provided with the usual PN to prevent depletion of essential fatty acids, lower the risk of hyperglycaemia, and prevent hepatic steatosis. Biologically active vitamin E (α-tocopherol) should continuously be administered along with lipid emulsions to reduce lipid peroxidation. Parenteral lipids should provide about 25–40% of the parenteral non-protein energy supply. In certain situations (i.e. critically ill, respiratory insufficiency) a lipid intake of up to 50 or 60% of non-protein energy may be reasonable. The recommended daily dose for parenteral lipids in adults is 0.7–1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l). There is little evidence at this time that the choice of different available lipid emulsions affects clinical endpoints. PMID:20049078

  14. Effects of Partial Beef Fat Replacement with Gelled Emulsion on Functional and Quality Properties of Model System Meat Emulsions

    PubMed Central

    2016-01-01

    The objective of this study was to investigate the effects of partial beef fat replacement (0, 30, 50, 100%) with gelled emulsion (GE) prepared with olive oil on functional and quality properties of model system meat emulsion (MSME). GE consisted of inulin and gelatin as gelling agent and characteristics of gelled and model system meat emulsions were investigated. GE showed good initial stability against centrifugation forces and thermal stability at different temperatures. GE addition decreased the pH with respect to increase in GE concentration. Addition of GE increased lightness and yellowness but reduced redness compared to control samples. The results of the study showed that partial replacement of beef fat with GE could be used for improving cooking yield without negative effects on water holding capacity and emulsion stability compared to C samples when replacement level is up to 50%. The presence of GE significantly affected textural behaviors of samples (p<0.05). In conclusion, our study showed that GE have promising impacts on developing healthier meat product formulations besides improving technological characteristics. PMID:28115885

  15. Accurate in situ measurement of complex refractive index and particle size in intralipid emulsions.

    PubMed

    Dong, Miao L; Goyal, Kashika G; Worth, Bradley W; Makkar, Sorab S; Calhoun, William R; Bali, Lalit M; Bali, Samir

    2013-08-01

    A first accurate measurement of the complex refractive index in an intralipid emulsion is demonstrated, and thereby the average scatterer particle size using standard Mie scattering calculations is extracted. Our method is based on measurement and modeling of the reflectance of a divergent laser beam from the sample surface. In the absence of any definitive reference data for the complex refractive index or particle size in highly turbid intralipid emulsions, we base our claim of accuracy on the fact that our work offers several critically important advantages over previously reported attempts. First, our measurements are in situ in the sense that they do not require any sample dilution, thus eliminating dilution errors. Second, our theoretical model does not employ any fitting parameters other than the two quantities we seek to determine, i.e., the real and imaginary parts of the refractive index, thus eliminating ambiguities arising from multiple extraneous fitting parameters. Third, we fit the entire reflectance-versus-incident-angle data curve instead of focusing on only the critical angle region, which is just a small subset of the data. Finally, despite our use of highly scattering opaque samples, our experiment uniquely satisfies a key assumption behind the Mie scattering formalism, namely, no multiple scattering occurs. Further proof of our method's validity is given by the fact that our measured particle size finds good agreement with the value obtained by dynamic light scattering.

  16. Accurate in situ measurement of complex refractive index and particle size in intralipid emulsions

    NASA Astrophysics Data System (ADS)

    Dong, Miao L.; Goyal, Kashika G.; Worth, Bradley W.; Makkar, Sorab S.; Calhoun, William R.; Bali, Lalit M.; Bali, Samir

    2013-08-01

    A first accurate measurement of the complex refractive index in an intralipid emulsion is demonstrated, and thereby the average scatterer particle size using standard Mie scattering calculations is extracted. Our method is based on measurement and modeling of the reflectance of a divergent laser beam from the sample surface. In the absence of any definitive reference data for the complex refractive index or particle size in highly turbid intralipid emulsions, we base our claim of accuracy on the fact that our work offers several critically important advantages over previously reported attempts. First, our measurements are in situ in the sense that they do not require any sample dilution, thus eliminating dilution errors. Second, our theoretical model does not employ any fitting parameters other than the two quantities we seek to determine, i.e., the real and imaginary parts of the refractive index, thus eliminating ambiguities arising from multiple extraneous fitting parameters. Third, we fit the entire reflectance-versus-incident-angle data curve instead of focusing on only the critical angle region, which is just a small subset of the data. Finally, despite our use of highly scattering opaque samples, our experiment uniquely satisfies a key assumption behind the Mie scattering formalism, namely, no multiple scattering occurs. Further proof of our method's validity is given by the fact that our measured particle size finds good agreement with the value obtained by dynamic light scattering.

  17. Fabrication of core-shell micro/nanoparticles for programmable dual drug release by emulsion electrospraying

    NASA Astrophysics Data System (ADS)

    Wang, Yazhou; Zhang, Yiqiong; Wang, Bochu; Cao, Yang; Yu, Qingsong; Yin, Tieying

    2013-06-01

    The study aimed at constructing a novel drug delivery system for programmable multiple drug release controlled with core-shell structure. The core-shell structure consisted of chitosan nanoparticles as core and polyvinylpyrrolidone micro/nanocoating as shell to form core-shell micro/nanoparticles, which was fabricated by ionic gelation and emulsion electrospray methods. As model drug agents, Naproxen and rhodamine B were encapsulated in the core and shell regions, respectively. The core-shell micro/nanoparticles thus fabricated were characterized and confirmed by scanning electron microscope, transmission electron microscope, and fluorescence optical microscope. The core-shell micro/nanoparticles showed good release controllability through drug release experiment in vitro. It was noted that a programmable release pattern for dual drug agents was also achieved by adjusting their loading regions in the core-shell structures. The results indicate that emulsion electrospraying technology is a promising approach in fabrication of core-shell micro/nanoparticles for programmable dual drug release. Such a novel multi-drug delivery system has a potential application for the clinical treatment of cancer, tuberculosis, and tissue engineering.

  18. Selective removal of erythromycin by magnetic imprinted polymers synthesized from chitosan-stabilized Pickering emulsion.

    PubMed

    Ou, Hongxiang; Chen, Qunhui; Pan, Jianming; Zhang, Yunlei; Huang, Yong; Qi, Xueyong

    2015-05-30

    Magnetic imprinted polymers (MIPs) were synthesized by Pickering emulsion polymerization and used to adsorb erythromycin (ERY) from aqueous solution. The oil-in-water Pickering emulsion was stabilized by chitosan nanoparticles with hydrophobic Fe3O4 nanoparticles as magnetic carrier. The imprinting system was fabricated by radical polymerization with functional and crosslinked monomer in the oil phase. Batches of static and dynamic adsorption experiments were conducted to analyze the adsorption performance on ERY. Isotherm data of MIPs well fitted the Freundlich model (from 15 °C to 35 °C), which indicated heterogeneous adsorption for ERY. The ERY adsorption capacity of MIPs was about 52.32 μmol/g at 15 °C. The adsorption kinetics was well described by the pseudo-first-order model, which suggested that physical interactions were primarily responsible for ERY adsorption. The Thomas model used in the fixed-bed adsorption design provided a better fit to the experimental data. Meanwhile, ERY exhibited higher affinity during adsorption on the MIPs compared with the adsorption capacity of azithromycin and chloramphenicol. The MIPs also exhibited excellent regeneration capacity with only about 5.04% adsorption efficiency loss in at least three repeated adsorption-desorption cycles.

  19. Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method

    NASA Astrophysics Data System (ADS)

    Wang, Qin; Wu, Puyuan; Ren, Wei; Xin, Kai; Yang, Yang; Xie, Chen; Yang, Chenchen; Liu, Qin; Yu, Lixia; Jiang, Xiqun; Liu, Baorui; Li, Rutain; Wang, Lifeng

    2014-07-01

    To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal.

  20. Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method

    PubMed Central

    2014-01-01

    To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal. PMID:25147486

  1. Nuclear research emulsion neutron spectrometry at the Little-Boy replica

    SciTech Connect

    Gold, R.; Roberts, J.H.; Preston, C.C.

    1985-10-01

    Nuclear research emulsions (NRE) have been used to characterize the neutron spectrum emitted by the Little-Boy replica. NRE were irradiated at the Little-Boy surface as well as approximately 2 m from the center of the Little-Boy replica using polar angles of 0/sup 0/, 30/sup 0/, 60/sup 0/ and 90/sup 0/. For the NRE exposed at 2 m, neutron background was determined using shadow shields of borated polyethylene. Emulsion scanning to date has concentrated exclusively on the 2-m, 0/sup 0/ and 2-m, 90/sup 0/ locations. Approximately 5000 proton-recoil tracks have been measured in NRE irradiated at each of these locations. Neutron spectra obtained from these NRE proton-recoil spectra are compared with both liquid scintillator neutron spectrometry and Monte Carlo calculations. NRE and liquid scintillator neutron spectra generally agree within experimental uncertainties at the 2-m, 90/sup 0/ location. However, at the 2-m, 0/sup 0/ location, the neutron spectra derived from these two independent experimental methods differ significantly. NRE spectra and Monte Carlo calculations exhibit general agreement with regard to both intensity as well as energy dependence. Better agreement is attained between theory and experiment at the 2-m, 90/sup 0/ location, where the neutron intensity is considerably higher. 14 refs., 18 figs., 11 tabs.

  2. The FASES instrument development and experiment preparation for the ISS

    NASA Astrophysics Data System (ADS)

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

    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

  3. Radiation induced emulsion graft polymerization of 4-vinylpyridine onto PE/PP nonwoven fabric for As(V) adsorption

    NASA Astrophysics Data System (ADS)

    Akkaş Kavaklı, Pınar; Kavaklı, Cengiz; Seko, Noriaki; Tamada, Masao; Güven, Olgun

    2016-10-01

    A novel nonwoven fabric adsorbent having 4-vinylpyridine functional groups was prepared by using radiation-induced emulsion graft polymerization method and grafting 4-vinylpyridine monomer onto a polyethylene-coated polypropylene nonwoven fabric (NWF) in aqueous emulsion solution. The grafting conditions of the 4-vinylpyridine monomer onto the NWF were optimised and 150% Dg VP-g-NWF was prepared using 30 kGy pre-irradiation dose, 5% VP monomer concentration and 0.5% (w/w) Tween 20 in aqueous emulsion. Grafted 4-vinylpyridine chains on the NWF were then quaternized for the preparation of QVP-g-NWF adsorbent. All fabric structures were characterized by using Fourier-transform infrared spectrometer, x-ray photoelectron spectrometer and scanning electron microscope. QVP-g-NWF adsorbent was used in batch adsorption experiments for As(V) ions by studying the pH, contact time, and initial As(V) ion concentration parameters. Results showed that QVP-g-NWF adsorbent has significant As(V) adsorption and experimental As(V) adsorption capacity was 98.04 mg As(V)/g polymer from 500 mg/L initial As(V) concentration at pH 7.00.

  4. Demonstration of polarization sensitivity of emulsion-based pair conversion telescope for cosmic gamma-ray polarimetry

    NASA Astrophysics Data System (ADS)

    Ozaki, Keita; Takahashi, Satoru; Aoki, Shigeki; Kamada, Keiki; Kaneyama, Taichi; Nakagawa, Ryo; Rokujo, Hiroki

    2016-10-01

    Linear polarization of high-energy gamma-rays (10MeV-100 GeV) can be detected by measuring the azimuthal angle of electron-positron pairs and observing the modulation of the azimuthal distribution. To demonstrate the gamma-ray polarization sensitivity of emulsion, we conducted a test using a polarized gamma-ray beam (0.8-2.4 GeV) at SPring-8/LEPS. Emulsion tracks were reconstructed using scanning data, and gamma-ray events were selected automatically. Using an optical microscope, out of the 2381 gamma-ray conversions that were observed, 1372 remained after event selection, on the azimuthal angle distribution of which we measured the modulation. From the distribution of the azimuthal angles of the selected events, a modulation factor of 0.21+0.11-0.09 was measured, from which the detection of a non-zero modulation was established with a significance of 3.06σ. This attractive polarimeter will be applied to the GRAINE project, a balloon-borne experiment that observes 10-100 GeV cosmic gamma-rays with an emulsion-based pair conversion telescope.

  5. Effect of the degree of substitution of octenyl succinic anhydride-banana starch on emulsion stability.

    PubMed

    Bello-Pérez, Luis A; Bello-Flores, Christopher A; Nuñez-Santiago, María del Carmen; Coronel-Aguilera, Claudia P; Alvarez-Ramirez, J

    2015-11-05

    Banana starch was esterified with octenylsuccinic anhydride (OSA) at different degree substitution (DS) and used to stabilize emulsions. Morphology, emulsion stability, emulsification index, rheological properties and particle size distribution of the emulsions were tested. Emulsions dyed with Solvent Red 26 showed affinity for the oil phase. Backscattering light showed three regions in the emulsion where the emulsified region was present. Starch concentration had higher effect in the emulsification index (EI) than the DS used in the study because similar values were found with OSA-banana and native starches. However, OSA-banana presented greater stability of the emulsified region. Rheological tests in emulsions with OSA-banana showed G'>G" values and low dependence of G' with the frequency, indicating a dominant elastic response to shear. When emulsions were prepared under high-pressure conditions, the emulsions with OSA-banana starch with different DS showed a bimodal distribution of particle size. The emulsion with OSA-banana starch and the low DS showed similar mean droplet diameter than its native counterpart. In contrast, the highest DS led to the highest mean droplet diameter. It is concluded that OSA-banana starch with DS can be used to stabilize specific emulsion types.

  6. Effect of emulsifiers and their liquid crystalline structures in emulsions on dermal and transdermal delivery of hydroquinone, salicylic acid and octadecenedioic acid.

    PubMed

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

    2010-01-01

    This study investigated the effect of emulsifiers and their liquid crystalline structures on the dermal and transdermal delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC). Emulsions containing liquid crystalline phases were compared with an emulsion without liquid crystals. Skin permeation experiments were performed using Franz-type diffusion cells and human abdominal skin dermatomed to a thickness of 400 mum. The results indicate that emulsifiers arranging in liquid crystalline structures in the water phase of the emulsion enhanced the skin penetration of the active ingredients with the exception of SA. SA showed a different pattern of percutaneous absorption, and no difference in dermal and transdermal delivery was observed between the emulsions with and without liquid crystalline phases. The increase in skin penetration of HQ and DIOIC could be attributed to an increased partitioning of the actives into the skin. It was hypothesized that the interaction between the different emulsifiers and active ingredients in the formulations varied and, therefore, the solubilization capacities of the various emulsifiers and their association structures.

  7. Laboratory Investigations in Support of Carbon Dioxide-in-Water Emulsions Stabilized by Fine Particles for Ocean and Geologic Sequestration of Carbon Dioxide

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan

    2006-07-08

    C/W emulsion, the total cost of preparing the emulsion on site is about $8.5 per ton of liquid CO{sub 2}, not including the cost of the emulsion mixer. Currently, the cost estimates of capturing and liquefying CO{sub 2} at a coal-fired power plant range from $15 to 75/t CO{sub 2}. Thus, the preparation of C/W emulsions stabilized by pulverized limestone particles would add about 10 to 50% to the capture cost of CO{sub 2}. At this juncture the primary research objectives of this Co-operative Agreement are shifting toward geologic sequestration of carbon dioxide. Experiments are underway to create micro-emulsions of CO{sub 2}-in-Water (C/W) and Water-in-CO{sub 2} (W/C) stabilized by ultrafine particles ranging from sub-micrometer to a few micrometer in size. Such microemulsions are expected to readily penetrate deep geologic formations, such as porous sedimentary layers, including saline aquifers and semi-depleted oil and gas fields. Injections of (C/W) and (W/C) type micro-emulsions may prove to be less prone to leakage from the formations compared to injections of neat liquid or supercritical CO{sub 2}.

  8. A Novel Submicron Emulsion System Loaded with Doxorubicin Overcome Multi-Drug Resistance in MCF-7/ADR Cells

    PubMed Central

    Zhou, W. P.; Hua, H. Y.; Sun, P. C.; Zhao, Y. X.

    2015-01-01

    The purpose of the present study was to develop the Solutol HS15-based doxorubicin submicron emulsion with good stability and overcoming multi-drug resistance. In this study, we prepared doxorubicin submicron emulsion, and examined the stability after autoclaving, the in vitro cytotoxic activity, the intracellular accumulation and apoptpsis of doxorubicin submicron emulsion in MCF-7/ADR cells. The physicochemical properties of doxorubicin submicron emulsion were not significantly affected after autoclaving. The doxorubicin submicron emulsion significantly increased the intracellular accumulation of doxorubicin submicron emulsion and enhanced cytotoxic activity and apoptotic effects of doxorubicin. These results may be correlated to doxorubicin submicron emulsion inhibitory effects on efflux pumps through the progressive release of intracellular free Solutol HS15 from doxorubicin submicron emulsion. Furthermore, these in vitro results suggest that the Solutol HS15-based submicron emulsion may be a potentially useful drug delivery system to circumvent multi-drug resistance of tumor cells. PMID:26664069

  9. That's a Phat Antidote: Intravenous Fat Emulsions and Toxicological Emergencies.

    PubMed

    Schultz, Amy E; Lewis, Temeka; Reed, Brittany S; Weant, Kyle A; Justice, Stephanie Baker

    2015-01-01

    Health care providers in the emergency department (ED) frequently find themselves caring for patients who may have overdosed on a medication(s) or other toxic substance. These patients can prove to be a challenge, as providers must try to determine the substance(s) involved so that the appropriate treatment can be initiated. For those patients who are hemodynamically unstable upon presentation, it is important to note that supportive care is of the utmost importance, as there are few substances that have antidotes available. In these situations, lipid emulsion can be considered. This is especially true in the setting of the following toxicities: local anesthetics, β-blockers, calcium channel blockers, and the tricyclic antidepressants. Even though lipid emulsion may not be used that frequently in the ED, it is important to be aware of its role in the setting of toxicological emergencies, how it should be dosed and administered, and the necessary safety precautions.

  10. Poly(isobutylene) nanoparticles via cationic polymerization in nonaqueous emulsions.

    PubMed

    Schuster, Thomas; Golling, Florian E; Krumpfer, Joseph W; Wagner, Manfred; Graf, Robert; Alsaygh, Abdulhamid A; Klapper, Markus; Müllen, Klaus

    2015-01-01

    The preparation of poly(isobutylene) (PIB) nanoparticles via cationic emulsion polymerization is presented. As a requirement, an oil-in-perfluoroalkane nonaqueous emulsion is developed, which is inert under the carbocationic polymerization conditions. To stabilize the dichloromethane/hexane droplets in the fluorinated, continuous phase, an amphiphilic block copolymer emulsifier is prepared containing PIB and 1H,1H-perfluoroalkylated poly(pentafluorostyrene) blocks. This system allows for the polymerization of isobutylene with number-average molecular weights (Mn) up to 27,000 g mol(-1). The particle morphologies are characterized via dynamic light scattering and electron microscopy. For Mn > 20,000 g mol(-1), the particles exhibit shape-persistence at room temperature and are ≈100 nm in diameter.

  11. Bioreactor droplets from liposome-stabilized all-aqueous emulsions

    NASA Astrophysics Data System (ADS)

    Dewey, Daniel C.; Strulson, Christopher A.; Cacace, David N.; Bevilacqua, Philip C.; Keating, Christine D.

    2014-08-01

    Artificial bioreactors are desirable for in vitro biochemical studies and as protocells. A key challenge is maintaining a favourable internal environment while allowing substrate entry and product departure. We show that semipermeable, size-controlled bioreactors with aqueous, macromolecularly crowded interiors can be assembled by liposome stabilization of an all-aqueous emulsion. Dextran-rich aqueous droplets are dispersed in a continuous polyethylene glycol (PEG)-rich aqueous phase, with coalescence inhibited by adsorbed ~130-nm diameter liposomes. Fluorescence recovery after photobleaching and dynamic light scattering data indicate that the liposomes, which are PEGylated and negatively charged, remain intact at the interface for extended time. Inter-droplet repulsion provides electrostatic stabilization of the emulsion, with droplet coalescence prevented even for submonolayer interfacial coatings. RNA and DNA can enter and exit aqueous droplets by diffusion, with final concentrations dictated by partitioning. The capacity to serve as microscale bioreactors is established by demonstrating a ribozyme cleavage reaction within the liposome-coated droplets.

  12. Field-induced structure of confined ferrofluid emulsion

    SciTech Connect

    Lawrence, E.M.; Ivey, M.L.; Flores, G.A.; Liu, J. . Dept. of Physics and Astronomy); Bibette, J. ); Richard, J. )

    1994-09-01

    Field-induced phase behavior of a confined monodisperse ferrofluid emulsion was studied using optical microscopy, light transmission, and static light scattering techniques. Upon application of magnetic field, randomly-dispersed magnetic emulsion droplets form solid structures at [lambda] = 1.5, where [lambda] is defines as the ratio of the dipole-dipole interaction energy to the thermal energy at room temperature. The new solid phase consists of either single droplet chains, columns, or worm-like clusters, depending on the volume fraction, cell thickness and rate of field application. For the column phase, an equilibrium structure of equally-sized and spaced columns was observed. The measurements taken for cell thickness 5[mu]m [<=] L [<=] 500 [mu]m and volume fraction 0.04 show the column spacing to be reasonably described by d = 1.49 L[sup 0.34].

  13. Asphalt emulsion sealing of uranium mill tailings. 1979 annual report

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-06-01

    Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt.

  14. From bijels to Pickering emulsions: A lattice Boltzmann study

    NASA Astrophysics Data System (ADS)

    Jansen, Fabian; Harting, Jens

    2011-04-01

    Particle stabilized emulsions are ubiquitous in the food and cosmetics industry, but our understanding of the influence of microscopic fluid-particle and particle-particle interactions on the macroscopic rheology is still limited. In this paper we present a simulation algorithm based on a multicomponent lattice Boltzmann model to describe the solvents combined with a molecular dynamics solver for the description of the solved particles. It is shown that the model allows a wide variation of fluid properties and arbitrary contact angles on the particle surfaces. We demonstrate its applicability by studying the transition from a “bicontinuous interfacially jammed emulsion gel” (bijel) to a “Pickering emulsion” in dependence on the contact angle, the particle concentration, and the ratio of the solvents.

  15. Intralipid emulsion treatment as an antidote in lipophilic drug intoxications.

    PubMed

    Eren Cevik, Sebnem; Tasyurek, Tanju; Guneysel, Ozlem

    2014-09-01

    Intravenous lipid emulsion (ILE) is a lifesaving treatment of lipophilic drug intoxications. Not only does ILE have demonstrable efficacy as an antidote to local anesthetic toxicity, it is also effective in lipophilic drug intoxications. Our case series involved 10 patients with ingestion of different types of lipophilic drugs. Intravenous lipid emulsion treatment improved Glasgow Coma Scale or blood pressure and pulse rate or both according to the drug type. Complications were observed in 2 patients (minimal change pancreatitis and probable ILE treatment-related fat infiltration in lungs). In our case series, ILE was used for different lipophilic drug intoxications to improve cardiovascular and neurologic symptoms. According to the results, it was found that ILE treatment is a lifesaving agent in lipophilic drug intoxications and it can be used in unconscious patients who have cardiac and/or neurologic symptoms but no history of a specific drug ingestion.

  16. Effect of irradiated pork on physicochemical properties of meat emulsions

    NASA Astrophysics Data System (ADS)

    Choi, Yun-Sang; Sung, Jung-Min; Jeong, Tae-Jun; Hwang, Ko-Eun; Song, Dong-Heon; Ham, Youn-Kyung; Kim, Hyun-Wook; Kim, Young-Boong; Kim, Cheon-Jei

    2016-02-01

    The effect of pork irradiated with doses up to 10 kGy on meat emulsions formulated with carboxy methyl cellulose (CMC) was investigated. Raw pork was vacuums packaged at a thickness of 2.0 cm and irradiated by X-ray linear accelerator (15 kW, 5 MeV). The emulsion had higher lightness, myofibrillar protein solubility, total protein solubility, and apparent viscosity with increasing doses, whereas cooking loss, total expressible fluid separation, and hardness decreased. There were no significant differences in fat separation, sarcoplasmic protein solubility, springiness, and cohesiveness. Our results indicated that it is treatment by ionizing radiation which causes the effects the physicochemical properties of the final raw meat product.

  17. On the transport of emulsions in porous media

    SciTech Connect

    Cortis, Andrea; Ghezzehei, Teamrat A.

    2007-06-27

    Emulsions appear in many subsurface applications includingbioremediation, surfactant-enhanced remediation, and enhancedoil-recovery. Modeling emulsion transport in porous media is particularlychallenging because the rheological and physical properties of emulsionsare different from averages of the components. Current modelingapproaches are based on filtration theories, which are not suited toadequately address the pore-scale permeability fluctuations and reductionof absolute permeability that are often encountered during emulsiontransport. In this communication, we introduce a continuous time randomwalk based alternative approach that captures these unique features ofemulsion transport. Calculations based on the proposed approach resultedin excellent match with experimental observations of emulsionbreakthrough from the literature. Specifically, the new approach explainsthe slow late-time tailing behavior that could not be fitted using thestandard approach. The theory presented in this paper also provides animportant stepping stone toward a generalizedself-consistent modeling ofmultiphase flow.

  18. Pharmaceutical emulsions: a new approach for gene therapy.

    PubMed

    Verissimo, Lourena Mafra; Lima, Lucymara Fassarela Agnez; Egito, Lucila Carmem Monte; de Oliveira, Anselmo Gomes; do Egito, E Sócrates Tabosa

    2010-06-01

    The concept of gene therapy involves the experimental transfer of a therapeutic gene into an individual's cells and tissues to replace an abnormal gene aiming to treat a disease, or to use the gene to treat a disease just like a medicine, improving the clinical status of a patient. The achievement of a foreigner nucleic acid into a population of cells requires its transfer to the target. Therefore, it is essential to create carriers (vectors) that transfer and protect the nucleic acid until it reaches the target. The obvious disadvantages of the use of viral vectors have directed the research for the development of a nonviral organized system such as emulsions. In fact, recently, there has been an increase of interest in its use in biotechnology as a nonviral vector for gene therapy. This review focuses on the progress of cationic emulsions and the improvement of the formulations, as a potential delivery system for gene therapy.

  19. Waste of cleaning emulsion sewage as inhibitors of steel corrosion

    NASA Astrophysics Data System (ADS)

    Fazullin, D. D.; Mavrin, G. V.; Shaikhiev, I. G.

    2016-06-01

    The article describes the corrosion test of steel of the brand 20 in the stratal water. To increase corrosion resistance as a corrosion inhibitor the concentrate waste emulsion of the mark "Incam- 1" was provided. The article presents studies of the corrosion rate with different dosages of corrosion inhibitor in the stratal water. Based on these research results are revealed that the degree of protection of steel is 27% at a dosage of 3.8 g / dm3.

  20. Incorporation of iodine in polymeric microparticles and emulsions

    NASA Astrophysics Data System (ADS)

    Kolontaeva, Olga A.; Khokhlova, Anastasia R.; Markina, Natalia E.; Markin, Alexey V.; Burmistrova, Natalia A.

    2016-04-01

    Application of different methods for formation of microcontainers containing iodine is proposed in this paper. Two types of microcontainers: microemulsions and microparticles have been investigated, conditions and methods for obtaining microcontainers were optimized. Microparticles were formed by layer-by-layer method with cores of calcium carbonate (CaCO3) as templates. Incorporation of complexes of iodine with polymers (chitosan, starch, polyvinyl alcohol) into core, shell and hollow capsules was investigated and loadings of microparticles with iodine were estimated. It was found that the complex of iodine with chitosan adsorbed at CaCO3 core is the most stable under physiological conditions and its value of loading can be 450 μg of I2 per 1 g of CaCO3. Moreover, chitosan was chosen as a ligand because of its biocompatibility and biodegradability as well as very low toxicity while its complex with iodine is very stable. A small amount of microparticles containing a iodine-chitosan complex can be used for prolonged release of iodine in the human body since iodine daily intake for adults is around 100 μg. "Oil-in-water" emulsions were prepared by ultrasonication of iodinated oils (sunflower and linseed) with sodium laurilsulfate (SLS) as surfactant solution. At optimal conditions, the homogenous emulsions remained stable for weeks, with total content of iodine in such emulsion being up to 1% (w/w). The oil:SLS ratio was equal to 1:10 (w/w), optimal duration and power of ultrasound exposure were 1.5 min and 7 W, correspondingly. Favorable application of iodized linseed oil for emulsion preparation with suitable oil microdroplets size was proved.

  1. A simple and low-cost 3d-printed emulsion generator

    NASA Astrophysics Data System (ADS)

    Zhang, J. M.; Aguirre-Pablo, A. A.; Li, E. Q.; Thoroddsen, S. T.

    2015-11-01

    The technique traditionally utilized to fabricate microfluidic emulsion generators, i.e. soft-lithography, is complex and expensive for producing three-dimensional (3D) structures. Here we apply 3D printing technology to fabricate a simple and low-cost 3D printed microfluidic device for emulsion generation without the need for surface treatment on the channel walls. This 3D-printed emulsion generator has been successfully tested over a range of conditions. We also formulate and demonstrate uniform scaling laws for emulsion droplets generated in different regimes for the first time, by incorporating the dynamic contact angle effects during the drop formation. Magnetically responsive microspheres are also produced with our emulsion templates, demonstrating the potential applications of this 3D emulsion generator in material and chemical engineering.

  2. Effect of emulsifier on oxidation properties of fish oil-based structured lipid emulsions.

    PubMed

    Fomuso, Lydia B; Corredig, Milena; Akoh, Casimir C

    2002-05-08

    The effects of the emulsifiers lecithin, Tween 20, whey protein isolate, mono-/diacylglycerols, and sucrose fatty acid ester on oxidation stability of a model oil-in-water emulsion prepared with enzymatically synthesized menhaden oil-caprylic acid structured lipid were evaluated. Oxidation was monitored by measuring lipid hydroperoxides, thiobarbituric acid reactive substances, and the ratio of combined docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents to palmitic acid in the emulsion. After high-pressure homogenization, all emulsions, except those prepared with lecithin, had similar droplet size distributions. All structured lipid emulsions, except for the lecithin-stabilized emulsions, were stable to creaming over the 48-day period studied. Emulsifier type and concentration affected oxidation rate, with 0.25% emulsifier concentration generally having a higher oxidation rate than 1% emulsifier concentration. Overall, oxidation did not progress significantly enough in 48 days of storage to affect DHA and EPA levels in the emulsion.

  3. Enhancement of lycopene bioaccessibility from tomato juice using excipient emulsions: Influence of lipid droplet size.

    PubMed

    Salvia-Trujillo, L; McClements, D J

    2016-11-01

    The use of excipient emulsions to increase the bioaccessibility of lycopene in tomato juice was studied by simulating gastrointestinal conditions. The influence of droplet diameter (d=0.17 or 19μm) and thermal treatment (90°C, 10min) on lycopene bioaccessibility was evaluated. Lycopene bioaccessibility was relatively low (<8%) in the absence of excipient emulsions due to the crystalline nature of the carotenoids and their entrapment within chromoplasts. Emulsions containing small droplets were fully digested within the small intestine phase, and led to a higher bioaccessibility (12.5%) than emulsions containing large droplets (10.0%) or emulsion-free samples (7.5%). The relatively modest increase in bioaccessibility was attributed to the high level of entrapment in crystalline form. Thermal processing did not appreciably disrupt tomato cells, and therefore only led to a slight increase in lycopene bioaccessibility. Overall, this study shows that excipient emulsions may increase the bioaccessibility of carotenoids in tomato juices.

  4. Pickering emulsions based on cyclodextrins: A smart solution for antifungal azole derivatives topical delivery.

    PubMed

    Leclercq, Loïc; Nardello-Rataj, Véronique

    2016-01-20

    Surfactants are usually used for the preparation of emulsions. Potential drawbacks on the human body or on the environment can be observed for some of them(e.g. skin irritation, hemolysis, protein denaturation, etc.). However, it is possible to use biocompatible emulsifiers such as native cyclodextrins (CDs). The mixture of oil (paraffin oil or isopropyl myristate), water and native CDs results in the formation of Pickering emulsions. The emulsion properties were investigated by ternary phase diagrams elaboration, multiple light scattering, optical and transmission microscopies. The results prove that these Pickering emulsions were very stable against coalescence due to the dense film format the oil/water interface. The rheological behavior has shown that these emulsions remain compatible for topical applications. This kind of emulsions (biocompatibility, stability and surfactant free) has been used to obtain sustainable formulations for antifungal econazole derivatives delivery. Our results prove that these new formulations are at least as active as commercially available formulations.

  5. Feasibility of Surfactant-Free Supported Emulsion Liquid Membrane Extraction

    NASA Technical Reports Server (NTRS)

    Hu, Shih-Yao B.; Li, Jin; Wiencek, John M.

    2001-01-01

    Supported emulsion liquid membrane (SELM) is an effective means to conduct liquid-liquid extraction. SELM extraction is particularly attractive for separation tasks in the microgravity environment where density difference between the solvent and the internal phase of the emulsion is inconsequential and a stable dispersion can be maintained without surfactant. In this research, dispersed two-phase flow in SELM extraction is modeled using the Lagrangian method. The results show that SELM extraction process in the microgravity environment can be simulated on earth by matching the density of the solvent and the stripping phase. Feasibility of surfactant-free SELM (SFSELM) extraction is assessed by studying the coalescence behavior of the internal phase in the absence of the surfactant. Although the contacting area between the solvent and the internal phase in SFSELM extraction is significantly less than the area provided by regular emulsion due to drop coalescence, it is comparable to the area provided by a typical hollow-fiber membrane. Thus, the stripping process is highly unlikely to become the rate-limiting step in SFSELM extraction. SFSELM remains an effective way to achieve simultaneous extraction and stripping and is able to eliminate the equilibrium limitation in the typical solvent extraction processes. The SFSELM design is similar to the supported liquid membrane design in some aspects.

  6. Plasma lipid levels in preterm neonates receiving parenteral fat emulsions.

    PubMed Central

    Hilliard, J L; Shannon, D L; Hunter, M A; Brans, Y W

    1983-01-01

    Concentrations of various plasma lipid fractions were determined during 96 hours of continuous parenteral infusions of lipid emulsions in 10 normally-grown neonates whose birth-weights ranged from 960 to 1760 g and whose gestational ages ranged from 26 to 32 weeks. Total lipid, triglyceride, free glycerol, and free fatty acid concentrations were measured. During lipid infusions, mean plasma concentrations of all lipid fractions increased above the mean preinfusion values if 2 g/kg a day or more of lipid emulsion was used. There were no further significant increases in mean plasma lipid levels if the infused dosage was increased to 3 or 4 g/kg a day. At these higher infusion rates however, there were considerable individual variations. The only neonate less than 27 weeks of gestation had plasma lipid levels severalfold higher than any of his peers, his plasma was frankly creamy on visual inspection, and the study had to be stopped. Further investigations are needed to determine the optimal modalities of parenteral nutrition with fat emulsions. PMID:6402989

  7. Functional properties of ultrasonically generated flaxseed oil-dairy emulsions.

    PubMed

    Shanmugam, Akalya; Ashokkumar, Muthupandian

    2014-09-01

    This study reports on the functional properties of 7% flaxseed oil/milk emulsion obtained by sonication (OM) using 20 kHz ultrasound (US) at 176 W for 1-8 min in two different delivery formulae, viz., ready-to-drink (RTD) and lactic acid gel. The RTD emulsions showed no change in viscosity after sonication for up to 8 min followed by storage up to a minimum of 9 days at 4±2 °C. Similarly, the oxidative stability of the RTD emulsion was studied by measuring the conjugated diene hydroperoxides (CD). The CD was unaffected after 8 min of ultrasonic processing. The safety aspect of US processing was evaluated by measuring the formation of CD at different power levels. The functional properties of OM gels were evaluated by small and large scale deformation studies. The sonication process improved the gelation characteristics, viz., decreased gelation time, increased elastic nature, decreased syneresis and increased gel strength. The presence of finer sono-emulsified oil globules, stabilized by partially denatured whey proteins, contributed to the improvements in the gel structure in comparison to sonicated and unsonicated pasteurized homogenized skim milk (PHSM) gels. A sono-emulsification process of 5 min followed by gelation for about 11 min can produce gels of highest textural attibutes.

  8. Intralipid Emulsion Rescue Therapy: Emerging Therapeutic Indications in Medical Practice.

    PubMed

    Muller, Sam H; Diaz, James H; Kaye, Alan David

    2016-01-01

    Intralipid emulsion therapy is well-established for the treatment of local-anesthetic systemic toxicities. In recent years, its role has expanded as an important therapeutic agent in the reversal of other types of drug overdoses, including certain types of antipsychotics, antidepressants, antiarrhythmics, and calcium channel blockers. A literature review identified thirty-one case reports including forty-nine separate drug overdose cases involving ten separate drug classes which were successfully reversed with Intralipid. The present clinical case study describes an elderly unresponsive woman refractory to conventional treatments after ingesting a potentially lethal amount of 5.6 grams of diltiazem in a suicide attempt. After treatment with Intralipid over a twenty-four hour period, the patient's hemodynamic and metabolic derangements were corrected and stabilized completely. Intralipid emulsion rescue therapy provides another potential strategy for the reversal of many drug toxicities, most likely by providing a lipid layer safety net for drug overdose by passive diffusion. Clinicians are urged to embrace an expanded role of Intralipid emulsion rescue therapy, not only for local anesthetic drug toxicities, but also for other lipophilic drug overdoses.

  9. Physics of puffing and microexplosion of emulsion fuel droplets

    NASA Astrophysics Data System (ADS)

    Shinjo, J.; Xia, J.; Ganippa, L. C.; Megaritis, A.

    2014-10-01

    The physics of water-in-oil emulsion droplet microexplosion/puffing has been investigated using high-fidelity interface-capturing simulation. Varying the dispersed-phase (water) sub-droplet size/location and the initiation location of explosive boiling (bubble formation), the droplet breakup processes have been well revealed. The bubble growth leads to local and partial breakup of the parent oil droplet, i.e., puffing. The water sub-droplet size and location determine the after-puffing dynamics. The boiling surface of the water sub-droplet is unstable and evolves further. Finally, the sub-droplet is wrapped by boiled water vapor and detaches itself from the parent oil droplet. When the water sub-droplet is small, the detachment is quick, and the oil droplet breakup is limited. When it is large and initially located toward the parent droplet center, the droplet breakup is more extensive. For microexplosion triggered by the simultaneous growth of multiple separate bubbles, each explosion is local and independent initially, but their mutual interactions occur at a later stage. The degree of breakup can be larger due to interactions among multiple explosions. These findings suggest that controlling microexplosion/puffing is possible in a fuel spray, if the emulsion-fuel blend and the ambient flow conditions such as heating are properly designed. The current study also gives us an insight into modeling the puffing and microexplosion of emulsion droplets and sprays.

  10. Fundamental Study of Emulsions Stabilized by Soft and Rigid Particles.

    PubMed

    Li, Zifu; Harbottle, David; Pensini, Erica; Ngai, To; Richtering, Walter; Xu, Zhenghe

    2015-06-16

    Two distinct uniform hybrid particles, with similar hydrodynamic diameters and comparable zeta potentials, were prepared by copolymerizing N-isopropylacrylamide (NIPAM) and styrene. These particles differed in their styrene to NIPAM (S/N) mass ratios of 1 and 8 and are referred to as S/N 1 and S/N 8, respectively. Particle S/N 1 exhibited a typical behavior of soft particles; that is, the particles shrank in bulk aqueous solutions when the temperature was increased. As a result, S/N 1 particles were interfacially active. In contrast, particle S/N 8 appeared to be rigid in response to temperature changes. In this case, the particles showed a negligible interfacial activity. Interfacial shear rheology tests revealed the increased rigidity of the particle-stabilized film formed at the heptane-water interface by S/N 1 than S/N 8 particles. As a result, S/N 1 particles were shown to be better emulsion stabilizers and emulsify a larger amount of heptane, as compared with S/N 8 particles. The current investigation confirmed a better performance of emulsion stabilization by soft particles (S/N 1) than by rigid particles (S/N 8), reinforcing the importance of controlling softness or deformability of particles for the purpose of stabilizing emulsions.

  11. Asphaltene self-association and water-in-hydrocarbon emulsions.

    PubMed

    Sztukowski, Danuta M; Jafari, Maryam; Alboudwarej, Hussein; Yarranton, Harvey W

    2003-09-01

    The configuration of asphaltenes on the water-oil interface was evaluated from a combination of molar mass, interfacial tension, drop size distribution, and gravimetric measurements of model emulsions consisting of asphaltenes, toluene, heptane, and water. Molar mass measurements were required because asphaltenes self-associate and the level of self-association varies with asphaltene concentration, the resin content, solvent type, and temperature. Plots of interfacial tension versus the log of asphaltene molar concentration were employed to determine the average interfacial area of asphaltene molecules on the interface. The moles of asphaltenes per area of emulsion interface were determined from the molar mass data as well as drop size distributions and gravimetric measurements of the model emulsions. The results indicate that asphaltenes form monolayers on the interface even at concentrations as high as 40 kg/m(3). As well, large aggregates with molar masses exceeding approximately 10,000 g/mol did not appear to adsorb at the interface. The area occupied by the asphaltenes on the interface was constant indicating that self-associated asphaltenes simply extend further into the continuous phase than nonassociated asphaltenes. The thickness of the monolayer ranged from 2 to 9 nm.

  12. Development of foamed emulsion bioreactor for air pollution control.

    PubMed

    Kan, Eunsung; Deshusses, Marc A

    2003-10-20

    A new type of bioreactor for air pollution control has been developed. The new process relies on an organic-phase emulsion and actively growing pollutant-degrading microorganisms, made into a foam with the air being treated. This new reactor is referred to as a foamed emulsion bioreactor (FEBR). As there is no packing in the reactor, the FEBR is not subject to clogging. Mathematical modeling of the process and proof of concept using a laboratory prototype revealed that the foamed emulsion bioreactor greatly surpasses the performance of existing gas-phase bioreactors. Experimental results showed a toluene elimination capacity as high as 285 g(toluene) m(-3) (reactor) h(-1) with a removal efficiency of 95% at a gas residence time of 15 s and a toluene inlet concentration of 1-1.3 g x m(-3). Oxygen limited the reactor performance at toluene concentration above about 0.7-1.0 g x m(-3); consequently, performance was significantly improved when pure oxygen was added to the contaminated air. The elimination capacity increased from 204 to 408 g x m(-3) h(-1) with >77% toluene removal at toluene inlet concentrations of 2-2.2 g x m(-3). Overall, the results show that the performance of the FEBR far exceeds that of currently used bioreactors for air pollution control.

  13. Olive Oil Based Emulsions in Frozen Puff Pastry Production

    NASA Astrophysics Data System (ADS)

    Gabriele, D.; Migliori, M.; Lupi, F. R.; de Cindio, B.

    2008-07-01

    Puff pastry is an interesting food product having different industrial applications. It is obtained by laminating layers of dough and fats, mainly shortenings or margarine, having specific properties which provides required spreading characteristic and able to retain moisture into dough. To obtain these characteristics, pastry shortenings are usually saturated fats, however the current trend in food industry is mainly oriented towards unsatured fats such as olive oil, which are thought to be safer for human health. In the present work, a new product, based on olive oil, was studied as shortening replacer in puff pastry production. To ensure the desired consistency, for the rheological matching between fat and dough, a water-in-oil emulsion was produced based on olive oil, emulsifier and a hydrophilic thickener agent able to increase material structure. Obtained materials were characterized by rheological dynamic tests in linear viscoelastic conditions, aiming to setup process and material consistency, and rheological data were analyzed by using the weak gel model. Results obtained for tested emulsions were compared to theological properties of a commercial margarine, adopted as reference value for texture and stability. Obtained emulsions are characterized by interesting rheological properties strongly dependent on emulsifier characteristics and water phase composition. However a change in process temperature during fat extrusion and dough lamination seems to be necessary to match properly typical dough rheological properties.

  14. Stabilising emulsion-based colloidal structures with mixed food ingredients.

    PubMed

    Dickinson, Eric

    2013-03-15

    The physical scientist views food as a complex form of soft matter. The complexity has its origin in the numerous ingredients that are typically mixed together and the subtle variations in microstructure and texture induced by thermal and mechanical processing. The colloid science approach to food product formulation is based on the assumption that the major product attributes such as appearance, rheology and physical stability are determined by the spatial distribution and interactions of a small number of generic structural entities (biopolymers, particles, droplets, bubbles, crystals) organised in various kinds of structural arrangements (layers, complexes, aggregates, networks). This review describes some recent advances in this field with reference to three discrete classes of dispersed systems: particle-stabilised emulsions, emulsion gels and aerated emulsions. Particular attention is directed towards explaining the crucial role of the macromolecular ingredients (proteins and polysaccharides) in controlling the formation and stabilisation of the colloidal structures. The ultimate objective of this research is to provide the basic physicochemical insight required for the reliable manufacture of novel structured foods with an appealing taste and texture, whilst incorporating a more healthy set of ingredients than those found in many existing traditional products.

  15. Novel anhydrous emulsions: formulation as controlled release vehicles.

    PubMed

    Suitthimeathegorn, Orawan; Jaitely, Vikas; Florence, Alexander T

    2005-07-25

    Novel anhydrous emulsions, which may offer some advantages as depot or reservoir vehicles for lipophilic drugs in controlled delivery systems, were formulated using castor oil as the disperse phase and dimethicone or cyclopentasiloxane as the continuous phase. Among the emulsifiers studied only silicone surfactants (cyclomethicone/dimethicone copolyols) which were miscible in silicone oil stabilized the emulsions. Cyclomethicone/PEG/PPG-18/18 Dimethicone and Cyclopentasiloxane/PEG/PPG-18/18 Dimethicone were more effective in lowering the interfacial tension between castor oil and both dimethicone and cyclopentasiloxane. Emulsions formulated using either of these two surfactants were found to be stable against phase separation and exhibited least globule growth over 168 h. The average particle size was found to be 2-6 microm in these systems formed by probe sonication. Slow release patterns of 3H-dehydroepiandrosterone (DHEA) and 3H-dexamethasone solubilized in the disperse castor oil phase into an aqueous dialyzing medium were observed over 48 h.

  16. Boiling of an emulsion in a yield stress fluid.

    PubMed

    Guéna, Geoffroy; Wang, Ji; d'Espinose, Jean-Baptiste; Lequeux, François; Talini, Laurence

    2010-11-01

    We report the boiling behavior of pentane emulsified in a yield stress fluid, a colloidal clay (Laponite) suspension. We have observed that a superheated state is easily reached: the emulsion, heated more than 50 °C above the alkane boiling point, does not boil. Superheating is made possible by the suppression of heterogeneous nucleation in pentane, resulting from the emulsification process, a phenomenon evidenced decades ago in studies of the superheating of two phase fluids. We have furthermore studied the growth of isolated bubbles nucleated in the emulsion. The rate of increase of the bubble radius with time depends on both the temperature and emulsion volume fraction but, rather unexpectedly, does not depend on the fluid rheology. We show that the bubbles grow by diffusion of the alkane through the aqueous phase between liquid droplets and bubbles, analogously to an Ostwald ripening process. The peculiarity of the process reported here is that a layer depleted in oil droplets forms around the bubble, layer to which the alkane concentration gradient is confined. We successfully describe our experimental results with a simple transfer model.

  17. Phase holograms in silver halide emulsions without a bleaching step

    NASA Astrophysics Data System (ADS)

    Belendez, Augusto; Madrigal, Roque F.; Pascual, Inmaculada V.; Fimia, Antonio

    2000-03-01

    Phase holograms in holographic emulsions are usually obtained by two bath processes (developing and bleaching). In this work we present a one step method to reach phase holograms with silver-halide emulsions. Which is based on the variation of the conditions of the typical developing processes of amplitude holograms. For this, we have used the well-known chemical developer, AAC, which is composed by ascorbic acid as a developing agent and sodium carbonate anhydrous as accelerator. Agfa 8E75 HD and BB-640 plates were used to obtain these phase gratings, whose colors are between yellow and brown. In function of the parameters of this developing method the resulting diffraction efficiency and optical density of the diffraction gratings were studied. One of these parameters studied is the influence of the grain size. In the case of Agfa plates diffraction efficiency around 18% with density < 1 has been reached, whilst with the BB-640 emulsion, whose grain is smaller than that of the Agfa, diffraction efficiency near 30% has been obtained. The resulting gratings were analyzed through X-ray spectroscopy showing the differences of the structure of the developed silver when amplitude and transmission gratings are obtained. The angular response of both (transmission and amplitude) gratings were studied, where minimal transmission is showed at the Braggs angle in phase holograms, whilst a maximal value is obtained in amplitude gratings.

  18. Particle shape anisotropy in pickering emulsions: cubes and peanuts.

    PubMed

    de Folter, Julius W J; Hutter, Eline M; Castillo, Sonja I R; Klop, Kira E; Philipse, Albert P; Kegel, Willem K

    2014-02-04

    We have investigated the effect of particle shape in Pickering emulsions by employing, for the first time, cubic and peanut-shaped particles. The interfacial packing and orientation of anisotropic microparticles are revealed at the single-particle level by direct microscopy observations. The uniform anisotropic hematite microparticles adsorb irreversibly at the oil-water interface in monolayers and form solid-stabilized o/w emulsions via the process of limited coalescence. Emulsions were stable against further coalescence for at least 1 year. We found that cubes assembled at the interface in monolayers with a packing intermediate between hexagonal and cubic and average packing densities of up to 90%. Local domains displayed densities even higher than theoretically achievable for spheres. Cubes exclusively orient parallel with one of their flat sides at the oil-water interface, whereas peanuts preferentially attach parallel with their long side. Those peanut-shaped microparticles assemble in locally ordered, interfacial particle stacks that may interlock. Indications for long-range capillary interactions were not found, and we hypothesize that this is related to the observed stable orientations of cubes and peanuts that marginalize deformations of the interface.

  19. Surface tension and quasi-emulsion of cavitation bubble cloud.

    PubMed

    Bai, Lixin; Chen, Xiaoguang; Zhu, Gang; Xu, Weilin; Lin, Weijun; Wu, Pengfei; Li, Chao; Xu, Delong; Yan, Jiuchun

    2017-03-01

    A quasi-emulsion phenomenon of cavitation structure in a thin liquid layer (the thin liquid layer is trapped between a radiating surface and a hard reflector) is investigated experimentally with high-speed photography. The transformation from cloud-in-water (c/w) emulsion to water-in-cloud (w/c) emulsion is related to the increase of cavitation bubble cloud. The acoustic field in the thin liquid layer is analyzed. It is found that the liquid region has higher acoustic pressure than the cloud region. The bubbles are pushed from liquid region to cloud region by the primary Bjerknes forces. The rate of change of CSF increased with the increase of CSF. The cavitation bubbles on the surface of cavitation cloud are attracted by the cavitation bubbles inside the cloud due to secondary Bjerknes forces. The existence of surface tension on the interface of liquid region and cloud region is proved. The formation mechanism of disc-shaped liquid region and cloud region are analysed by surface tension and incompressibility of cavitation bubble cloud.

  20. Enhanced fluorescence emitted by microdroplets containing organic dye emulsions

    PubMed Central

    Nastasa, V.; Andrei, I. R.; Staicu, Angela; Pascu, M. L.

    2015-01-01

    In this paper, laser beam resonant interaction with pendant microdroplets that are seeded with a laser dye (Rhodamine 6G (Rh6G)) water solution or oily Vitamin A emulsion with Rhodamine 6G solution in water is investigated through fluorescence spectra analysis. The excitation is made with the second harmonic generated beam emitted by a pulsed Nd:YAG laser system at 532 nm. The pendant microdroplets containing emulsion exhibit an enhanced fluorescence signal. This effect can be explained as being due to the scattering of light by the sub-micrometric drops of oily Vitamin A in emulsion and by the spherical geometry of the pendant droplet. The droplet acts as an optical resonator amplifying the fluorescence signal with the possibility of producing lasing effect. Here, we also investigate how Rhodamine 6G concentration, pumping laser beam energies and number of pumping laser pulses influence the fluorescence behavior. The results can be useful in optical imaging, since they can lead to the use of smaller quantities of fluorescent dyes to obtain results with the same quality. PMID:25784965

  1. Heavy nucleus collisions between 20 and 60 GeV/nucleon

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    Interest in studying relativistic nucleus-nucleus interations arises from the fact that they offer an opportunity to probe nuclear matter at high density and temperature. It is expected that under such extreme conditions a transition from hadronic matter into quark-gluon plasma occurs and that in the interactions of highly relativistic nuclei such conditions are created. Cosmic rays remain a unique source of high energy heavy nuclei. The Japanese-American Cooperative Emulsion Experiment (JACEE-3) was designed to study the collisions of heavy cosmic ray nuclei with different nuclear targets at energies beyond 20 GeV/nucleon. JACEE-3 experiment was carried out using a combined electronic counters and an emulsion chamber detector, which was exposed to the cosmic rays on a balloon at an altitude of 5 g/sq cm.

  2. Development of stable flaxseed oil emulsions as a potential delivery system of ω-3 fatty acids.

    PubMed

    Goyal, Ankit; Sharma, Vivek; Upadhyay, Neelam; Singh, A K; Arora, Sumit; Lal, Darshan; Sabikhi, Latha

    2015-07-01

    The objective of the present study was to develop a stable flaxseed oil emulsion for the delivery of omega-3 (ω-3) fatty acids through food fortification. Oil-in-water emulsions containing 12.5 % flaxseed oil, 10 % lactose and whey protein concentrate (WPC)-80 ranging from 5 to 12.5 % were prepared at 1,500, 3,000 and 4,500 psi homogenization pressure. Flaxseed oil emulsions were studied for its physical stability, oxidative stability (peroxide value), particle size distribution, zeta (ζ)-potential and rheological properties. Emulsions homogenized at 1,500 and 4,500 psi pressure showed oil separation and curdling of WPC, respectively, during preparation or storage. All the combinations of emulsions (homogenized at 3,000 psi) were physically stable for 28 days at 4-7 ºC temperature and did not show separation of phases. Emulsion with 7.5 % WPC showed the narrowest particle size distribution (190 to 615 nm) and maximum zeta (ζ)-potential (-33.5 mV). There was a slight increase in peroxide value (~20.98 %) of all the emulsions (except 5 % WPC emulsion), as compared to that of free flaxseed oil (~44.26 %) after 4 weeks of storage. Emulsions showed flow behavior index (n) in the range of 0.206 to 0.591, indicating higher shear thinning behavior, which is a characteristic of food emulsions. Results indicated that the most stable emulsion of flaxseed oil (12.5 %) can be formulated with 7.5 % WPC-80 and 10 % lactose (filler), homogenized at 3,000 psi pressure. The formulated emulsion can be used as potential omega-3 (ω-3) fatty acids delivery system in developing functional foods such as pastry, ice-creams, curd, milk, yogurt, cakes, etc.

  3. Ultrasound-assisted Micro-emulsion Synthesis of a Highly Active Nano-particle Catalyst

    DTIC Science & Technology

    2010-03-01

    Ultrasound-assisted Micro -emulsion Synthesis of a Highly Active Nano -particle Catalyst by Rongzhong Jiang and Charles Rong ARL-TR-5114...ARL-TR-5114 March 2010 Ultrasound-assisted Micro -emulsion Synthesis of a Highly Active Nano -particle Catalyst Rongzhong Jiang and...TYPE DRI 3. DATES COVERED (From - To) 2009 to 2010 4. TITLE AND SUBTITLE Ultrasound-assisted Micro -emulsion Synthesis of a Highly Active Nano

  4. Internal Dosimetry of a Chylomicron-like Emulsion Labeled with 14C-CE in Humans

    NASA Astrophysics Data System (ADS)

    Marcato, Larissa A.; Carvalho, Diego V. S.; Hamada, Margarida M.; Vinagre, Carmen G.; Maranhão, Raul C.; de Mesquita, Carlos H.

    2011-08-01

    This paper estimates the value of the effective equivalent dose in humans due to intravenous injection of chylomicron-like emulsion radiolabeled with 14C-CE. A kinetic model for the chylomicron-like emulsion in human body was proposed. The removal parameters of chylomicron-like emulsion from the plasma were evaluated by compartimental analysis. Radiometric doses were calculated using AnaComp software and the MIRD formalism.

  5. Determination of thermal process schedule for emulsion type buffalo meat block in retort pouch.

    PubMed

    Devadason, I Prince; Anjaneyulu, A S R; Mendirtta, S K; Murthy, T R K

    2014-11-01

    The process temperature for buffalo met blocks processed in retort pouches calculated based on the heat resistance of Clostridium sporogenes PA 3679 in Phosphate buffer saline (PBS- Ph 7.0) as reference medium and in buffalo meat block (pH 6.28) was in the range of 110-121°C. The D values and Z values calculated for C.sporogenes PA 3679 confirmed that the suspension was best suited for conducting thermal resistance studies. The experiment for indirect confirmation of microbial safety of the products involving inoculating the buffalo meat emulsion filled in pouches with C.sporogenes PA 3679 and processed at Fo 12.13 min showed no growth of microorganisms.

  6. Fibrous scaffolds fabricated by emulsion electrospinning: from hosting capacity to in vivo biocompatibility.

    PubMed

    Spano, F; Quarta, A; Martelli, C; Ottobrini, L; Rossi, R M; Gigli, G; Blasi, L

    2016-04-28

    Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post-implantation.

  7. Bursting of dilute emulsion-based liquid sheets driven by a Marangoni effect

    NASA Astrophysics Data System (ADS)

    Ligoure, Christian; Ramos, Laurence; Vernay, Clara; SoftMatter Team

    2015-11-01

    We study the destabilization mechanism of thin liquid sheets expanding in air and show that dilute oil-in-water emulsion-based sheets disintegrate through the nucleation and growth of holes that perforate the sheet. The velocity and thickness fields of the sheet are not perturbed by holes and hole opening follows a Taylor-Culick law. We find that a pre-hole, which widens and thins out the sheet with time, systematically precedes the hole nucleation. The growth dynamics of the pre-hole follows the law theoretically predicted for a liquid spreading on another liquid of higher surface tension due to Marangoni stresses. Classical Marangoni spreading experiments quantitatively corroborate those findings.

  8. Bursting of Dilute Emulsion-Based Liquid Sheets Driven by a Marangoni Effect

    NASA Astrophysics Data System (ADS)

    Vernay, Clara; Ramos, Laurence; Ligoure, Christian

    2015-11-01

    We study the destabilization mechanism of thin liquid sheets expanding in air and show that dilute oil-in-water emulsion-based sheets disintegrate through the nucleation and growth of holes that perforate the sheet. The velocity and thickness fields of the sheet outside the holes are not perturbed by holes, and hole opening follows the Taylor-Culick law. We find that a prehole, which widens and thins out the sheet with time, systematically precedes the hole nucleation. The growth dynamics of the prehole follows the law theoretically predicted for a liquid spreading on another liquid of higher surface tension due to Marangoni stresses. Classical Marangoni spreading experiments quantitatively corroborate our findings.

  9. On the characteristics of emulsion chamber family events produced in low heights

    NASA Technical Reports Server (NTRS)

    Jing, G.; Jing, C.; Zhu, Q.; Ding, L.

    1985-01-01

    The uncertainty of the primary cosmic ray composition at 10 to the 14th power -10 to the 16th power eV is well known to make the study of the nuclear interaction mechanism more difficult. Experimentally considering, if one can identify effectively the family events which are produced in low heights, then an event sample induced by primary protons might be able to be separated. It is undoubtedly very meaningful. In this paper an attempt is made to simulate the family events under the condition of mountain emulsion chamber experiments with a reasonable model. The aim is to search for the dependence of some experimentally observable quantities to the interaction height.

  10. Starch-based Pickering emulsions for topical drug delivery: A QbD approach.

    PubMed

    Marto, J; Gouveia, L; Jorge, I M; Duarte, A; Gonçalves, L M; Silva, S M C; Antunes, F; Pais, A A C C; Oliveira, E; Almeida, A J; Ribeiro, H M

    2015-11-01

    Pickering emulsions are stabilized by solid particles instead of surfactants and have been widely investigated in pharmaceutical and cosmetic fields since they present less adverse effects than the classical emulsions. A quality by design (QbD) approach was applied to the production of w/o emulsions stabilized by starch. A screening design was conducted to identify the critical variables of the formula and the process affecting the critical quality properties of the emulsion (droplet size distribution). The optimization was made by establishing the Design Space, adjusting the concentration of starch and the quantity of the internal aqueous phase. The emulsion production process was, in turn, adjusted by varying the time and speed of stirring, to ensure quality and minimum variability. The stability was also investigated, demonstrating that an increase in starch concentration improves the stability of the emulsion. Rheological and mechanical studies indicated that the viscosity of the emulsions was enhanced by the addition of starch and, to a higher extent, by the presence of different lipids. The developed formulations was considered non-irritant, by an in vitro assay using human cells from skin (Df and HaCat) with the cell viability higher than 90% and, with self-preserving properties. Finally, the QbD approach successfully built quality in Pickering emulsions, allowing the development of hydrophilic drug-loaded emulsions stabilized by starch with desired organoleptic and structural characteristics. The results obtained suggest that these systems are a promising vehicle to be used in products for topical administration.

  11. A computer system to analyze showers in nuclear emulsions: Center Director's discretionary fund report

    NASA Technical Reports Server (NTRS)

    Meegan, C. A.; Fountain, W. F.; Berry, F. A., Jr.

    1987-01-01

    A system to rapidly digitize data from showers in nuclear emulsions is described. A TV camera views the emulsions though a microscope. The TV output is superimposed on the monitor of a minicomputer. The operator uses the computer's graphics capability to mark the positions of particle tracks. The coordinates of each track are stored on a disk. The computer then predicts the coordinates of each track through successive layers of emulsion. The operator, guided by the predictions, thus tracks and stores the development of the shower. The system provides a significant improvement over purely manual methods of recording shower development in nuclear emulsion stacks.

  12. Formulation parameters influencing the physicochemical characteristics of rosiglitazone-loaded cationic lipid emulsion.

    PubMed

    Davaa, Enkhzaya; Park, Jeong-Sook

    2012-07-01

    To enhance the solubility of rosiglitazone, rosiglitazone-loaded cationic lipid emulsion was formulated using cationic lipid DOTAP, DOPE, castor oil, tween 20, and tween 80. The formulation parameters in terms of droplet size were optimized focused on the effect of the cationic lipid emulsion composition ratio on drug encapsulating efficiency, in vitro drug release, and cellular uptake of the rosiglitazone-loaded emulsion. Droplet sizes of a blank cationic emulsion and a rosiglitazone-loaded cationic emulsion ranged between 195-230 nm and 210-290 nm, respectively. The encapsulation efficiency of the rosiglitazone-loaded emulsion was more than 90%. The rosiglitazone-loaded cationic emulsion improved in vitro drug release over the drug alone and showed a much higher cellular uptake than rosiglitazone alone. Moreover, drug loading in cationic emulsions increased cellular uptake of rosiglitazone in insulin-resistant HepG2 cells more than the normal HepG2 cells. Taken together, these results indicate that cationic lipid emulsions could be a potential delivery system for rosiglitazone and could enhance its cellular uptake efficiency into target cells.

  13. Fabrication and characterization of antioxidant pickering emulsions stabilized by zein/chitosan complex particles (ZCPs).

    PubMed

    Wang, Li-Juan; Hu, Ya-Qiong; Yin, Shou-Wei; Yang, Xiao-Quan; Lai, Fu-Rao; Wang, Si-Qi

    2015-03-11

    Lipid peroxidation in oil-in-water (o/w) emulsions leads to rancidity and carcinogen formation. This work attempted to protect lipid droplets of emulsions from peroxidation via manipulation of the emulsions' interface framework using dual-function zein/CH complex particles (ZCPs). ZCP with intermediate wettability was fabricated via a simple antisolvent approach. Pickering emulsions were produced via a simple and inexpensive shear-induced emulsification technique. ZCP was irreversibly anchored at the oil-water interface to form particle-based network architecture therein, producing ultrastable o/w Pickering emulsions (ZCPEs). ZCPE was not labile to lipid oxidation, evidenced by low lipid hydroperoxides and malondialdehyde levels in the emulsions after thermally accelerated storage. The targeted accumulation of curcumin, a model antioxidant, at the interface was achieved using the ZCP as interfacial vehicle, forming antioxidant shells around dispersed droplets. The oxidative stability of ZCPEs was further improved. Interestingly, no detectable hexanal peak appeared in headspace gas chromatography of the Pickering emulsions. The novel interfacial architecture via the combination of steric hindrance from ZCP-based membrane and interfacial cargo of curcumin endowed the emulsions with favorable oxidative stability. This study opens a promising pathway for producing antioxidant emulsions via the combination of Pickering stabilization mechanism and interfacial delivery of antioxidant.

  14. Factors influencing the stability and type of hydroxyapatite stabilized Pickering emulsion.

    PubMed

    Zhang, Ming; Wang, Ai-Juan; Li, Jun-Ming; Song, Na; Song, Yang; He, Rui

    2017-01-01

    Hydroxyapatite (HAp) nanoparticle stabilized Pickering emulsion was fabricated with poly(l-lactic acid) dissolved in dichloromethane (CH2Cl2) solution as oil phase and HAp aqueous dispersion as aqueous phase. Pickering emulsion was cured via in situ solvent evaporation method. Effect of PLLA concentrations, pH value, HAp concentrations, oil-water ratio, emulsification rates and times were studied on emulsion stability and emulsion type, etc. The results indicated emulsion stability increased with the increase of HAp concentration, emulsification rate and time; it is very stable when pH value of aqueous phase was adjusted to 10. Stable W/O and O/W emulsions were fabricated successfully using as-received HAp particles as stabilizer by adjusting the fabricating parameters. The interaction between HAp and PLLA played an important role to stabilize Pickering emulsions. SEM results indicated that both microsphere and porous materials were fabricated using emulsion stabilized by unmodified HAp nanoparticles, implying that both W/O and O/W emulsion type were obtained.

  15. Fibrous scaffolds fabricated by emulsion electrospinning: from hosting capacity to in vivo biocompatibility

    NASA Astrophysics Data System (ADS)

    Spano, F.; Quarta, A.; Martelli, C.; Ottobrini, L.; Rossi, R. M.; Gigli, G.; Blasi, L.

    2016-04-01

    Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post-implantation.Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post

  16. Tunable Pickering Emulsions with Environmentally Responsive Hairy Silica Nanoparticles.

    PubMed

    Liu, Min; Chen, Xiaoli; Yang, Zongpeng; Xu, Zhou; Hong, Liangzhi; Ngai, To

    2016-11-30

    Surface modification of the nanoparticles using surface anchoring of amphiphilic polymers offers considerable scope for the design of a wide range of brush-coated hybrid nanoparticles with tunable surface wettability that may serve as new class of efficient Pickering emulsifiers. In the present study, we prepared mixed polymer brush-coated nanoparticles by grafting ABC miktoarm star terpolymers consisting of poly(ethylene glycol), polystyrene, and poly[(3-triisopropyloxysilyl)propyl methacrylate] (μ-PEG-b-PS-b-PIPSMA) on the surface of silica nanoparticles. The wettability of the as-prepared nanoparticles can be precisely tuned by a change of solvent or host-guest complexation. (1)H NMR result confirmed that such wettability change is due to the reorganization of the polymer chain at the grafted layer. We show that this behavior can be used for stabilization and switching between water-in-oil (W/O) and oil-in-water (O/W) emulsions. For hairy particles initially dispersed in oil, W/O emulsions were always obtained with collapsed PEG chains and mobile PS chains at the grafted layer. However, initially dispersing the hairy particles in water resulted in O/W emulsions with collapsed PS chains and mobile PEG chains. When a good solvent for both PS and PEG blocks such as toluene was used, W/O emulsions were always obtained no matter where the hairy particles were dispersed. The wettability of the mixed polymer brush-coated silica particles can also be tuned by host-guest complexation between PEG block and α-CD. More importantly, our result showed that surprisingly the resultant mixed brush-coated hairy nanoparticles can be employed for the one-step production of O/W/O multiple emulsions that are not attainable from conventional Pickering emulsifiers. The functionalized hairy silica nanoparticles at the oil-water interface can be further linked together utilizing poly(acrylic acid) as the reversible linker to form supramolecular colloidosomes, which show p

  17. Interparticle interactions in concentrate water-oil emulsions.

    PubMed

    Mishchuk, N A; Sanfeld, A; Steinchen, A

    2004-12-31

    The present investigation is based on the description of electrostatic interaction in concentrated disperse systems proposed 45 years ago by Albers and Overbeek. Starting from their model, we developed a stability theory of concentrated Brownian W/O emulsions in which nondeformed droplets undergo electrostatic and Van der Waals interactions. While the droplets in dilute emulsion may be described by pair interaction, in dense emulsions, every droplet is closely surrounded by other droplets, and when two of them come together, not only the energy of their pair interaction, but also their interaction with surrounding droplets change. Unlike in dilute emulsion, for which the reference energy of the pair is the energy at infinity (taken equal to zero), in concentrate emulsion, the reference energy is not zero but is the energy of interaction with averaged ensemble of nearest droplets. The larger the volume fraction, the higher the reference energy and, thus, the lower the energy barrier between two coagulating droplets, which enhances the coagulation. In dense packing of drops, the energy of interaction and the reference energy coincide, therefore, the height of energy barrier vanishes. In contrast with dense emulsion, at medium volume fraction, when two coagulating droplets interact only with a few nearest neighbors, our analysis shows that the energy barrier may also increase, which extends thus the domain of stability. Because in W/O emulsion, the thickness of the electric double layer is of the same order or larger than the size of droplets, the electrostatic energy was calculated with a correction factor beta that accounts for the deviation of double layers from sphericity. A more complete van der Waals interaction with account of screening of interaction by electrolyte has been used. Both factors promote the decrease of energy barrier between coagulating droplets and enhance the coagulation. Our model introduces two critical volume fractions. The first one, phi(c1

  18. The Effect of Fish Oil-Based Lipid Emulsion and Soybean Oil-Based Lipid Emulsion on Cholestasis Associated with Long-Term Parenteral Nutrition in Premature Infants

    PubMed Central

    Wang, Leilei; Zhang, Jing; Gao, Jiejin; Qian, Yan; Ling, Ya

    2016-01-01

    Purpose. To retrospectively study the effect of fish oil-based lipid emulsion and soybean oil-based lipid emulsion on cholestasis associated with long-term parenteral nutrition in premature infants. Methods. Soybean oil-based lipid emulsion and fish oil-based lipid emulsion had been applied in our neonatology department clinically between 2010 and 2014. There were 61 qualified premature infants included in this study and divided into two groups. Soybean oil group was made up of 32 premature infants, while fish oil group was made up of 29 premature infants. Analysis was made on the gender, feeding intolerance, infection history, birth weight, gestational age, duration of parenteral nutrition, total dosage of amino acid, age at which feeding began, usage of lipid emulsions, and incidence of cholestasis between the two groups. Results. There were no statistical differences in terms of gender, feeding intolerance, infection history, birth weight, gestational age, duration of parenteral nutrition, total dosage of amino acid, and age at which feeding began. Besides, total incidence of cholestasis was 21.3%, and the days of life of occurrence of cholestasis were 53 ± 5.0 days. Incidence of cholestasis had no statistical difference in the two groups. Conclusion. This study did not find the different role of fish oil-based lipid emulsions and soybean oil-based lipid emulsions in cholestasis associated with long-term parenteral nutrition in premature infants. PMID:27110237

  19. Reduction of the infectivity of baculovirus stocks frozen at ultra-low temperature in serum-free media: The role of lipid emulsions.

    PubMed

    Eberhardt, Ignacio; Gioria, Verónica Viviana; Micheloud, Gabriela Analía; Claus, Juan Daniel

    2016-11-01

    The infectivity of stocks of baculoviruses produced in serum-free media is sensitive to freezing at ultra-low temperatures. The objective of this work was to elucidate the causes of such sensitivity, using as a model the freezing of stocks of Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV), a baculovirus widely employed as biological insecticide. Titers of supernatants of cell cultures infected with AgMNPV in four different serum-free media supplemented with lipid emulsions were reduced by 50 to 90% after six months freezing. By using a full factorial experiment, freezing and lipid emulsion, as well as the interaction between them, were identified as the main factors reducing the viral titer. The virucidal effect of the lipid emulsion was reproduced by one of their components, the surfactant Polysorbate 80. Damaged viral envelopes were observed by transmission electron microscopy in most particles frozen in a medium supplemented with lipid emulsion or Polysorbate 80. Additionally, Polysorbate 80 also affected the infectivity of AgMNPV stocks that were incubated at 27°C. The identification of the roles played by the lipid emulsion and Polysorbate 80 is not only a contribution to the understanding of the mechanisms underlying the inactivation of baculovirus stocks produced in serum-free media during storage at ultra-low temperature, but is also an input for the rational development of new procedures aimed at improving both the preservation of baculovirus stocks and the composition of culture media for the production of baculovirus-based bioproducts in insect cells. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1559-1569, 2016.

  20. CHARACTERIZATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND OIL RECOVERY FOR NOVEL ALCOHOL ETHOXYCARBOXYLATE SURFACTANTS

    SciTech Connect

    Lebone T. Moeti; Ramanathan Sampath

    2001-09-28

    This final technical report describes work performed under DOE Grant No. DE-FG26-97FT97278 during the period October 01, 1997 to August 31, 2001 which covers the total performance period of the project. During this period, detailed information on optimal salinity, temperature, emulsion morphologies, effectiveness for surfactant retention and oil recovery was obtained for an Alcohol Ethoxycarboxylate (AEC) surfactant to evaluate its performance in flooding processes. Tests were conducted on several AEC surfactants and NEODOX (23-4) was identified as the most suitable hybrid surfactant that yielded the best proportion in volume for top, middle, and bottom phases when mixed with oil and water. Following the selection of this surfactant, temperature and salinity scans were performed to identify the optimal salinity and temperature, and the temperature and salinity intervals in which all three phases coexisted. NEODOX 23-4 formed three phases between 4 and 52.5 C. It formed an aqueous rich microemulsion phase at high temperatures and an oleic rich microemulsion phase at low temperatures--a characteristic of the ionic part of the surfactant. The morphology measurement system was set-up successfully at CAU. The best oil/water/surfactant system defined by the above phase work was then studied for emulsion morphologies. Electrical conductivities were measured for middle and bottom phases of the NEODOX 23-4/dodecane/10mM water system and by mixing measured volumes of the middle phase into a fixed volume of the bottom phase and vice versa at room temperature. Electrical conductivity of the mixture decreased as the fraction of volume of the middle phase was increased and vice versa. Also inversion phenomena was observed. These experiments were then repeated for bottom/middle (B/M) and middle/bottom (M/B) conjugate pair phases at 10, 15, 25, 30, 35, 40, and 45 C. Electrical conductivity measurements were then compared with the predictions of the conductivity model developed in

  1. Discovery of naked charm particles and lifetime differences among charm species using nuclear emulsion techniques innovated in Japan

    PubMed Central

    NIU, Kiyoshi

    2008-01-01

    This is a historical review of the discovery of naked charm particles and lifetime differences among charm species. These discoveries in the field of cosmic-ray physics were made by the innovation of nuclear emulsion techniques in Japan. A pair of naked charm particles was discovered in 1971 in a cosmic-ray interaction, three years prior to the discovery of the hidden charm particle, J/Ψ, in western countries. Lifetime differences between charged and neutral charm particles were pointed out in 1975, which were later re-confirmed by the collaborative Experiment E531 at Fermilab. Japanese physicists led by K.Niu made essential contributions to it with improved emulsion techniques, complemented by electronic detectors. This review also discusses the discovery of artificially produced naked charm particles by us in an accelerator experiment at Fermilab in 1975 and of multiple-pair productions of charm particles in a single interaction in 1987 by the collaborative Experiment WA75 at CERN. PMID:18941283

  2. Characteristics of central collision events in Fe-nucleus interactions for 20 - 60 GeV/nucleon

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    A counter emulsion hybrid chamber in Japanese-American Cooperative Emulsion Experiment (JACEE-3) was flown on a balloon at the altitude (5.4 g/sq cm) in 1982 with the objective of probing the heavy nuclear collisions above 20 GeV per nucleon. In the energy region, it is suggested that nucleus-nucleus collisions provide dense collisions complex through compression and secondary particle production. In the lower energy region, an evidence of collective flow has been reported. And also, at higher energy region, it has been argued that nucleus has rather large stopping power. In this paper, the high multiplicity characteristics of Fe nucleus central collisions with energies 20 to 50 GeV/nucleon are presented. This is considered to be relevant to compressibility and collective flow of nuclear matter.

  3. Dynamic filtration of invert-emulsion muds

    SciTech Connect

    Jiao, D.; Sharma, M.M. )

    1993-09-01

    Dynamic-filtration experiments conducted on oil-based muds show that the dynamic-filtration rate is much higher than API filtration rates. The use of water-wet solids results in very poor-quality external mudcakes and high fluid-loss rates. Better external mudcakes are formed by mixing equal parts organophilic clay and mud. Filtration-loss-control additives (asphalt mineral pitches) do not reduce the equilibrium filtration rate, but do reduce spurt loss and limit solids invasion. In brine-saturated rocks, the invasion rate for oil-based muds is significantly smaller than for water-based muds because capillary pressure prevents the oil phase from entering the core in oil-based muds. Oil-based mudcakes are softer and more shear-sensitive than water-based mudcakes. Scanning electron microscope (SEM) photomicrographs indicate that oil-based mudcakes consist of individual water droplets coated with clay particles. This cake structure gives rise to the low permeability and shear sensitivity of oil-based muds.

  4. Exploring the effect of intravenous lipid emulsion in acute methamphetamine toxicity

    PubMed Central

    Ghadiri, Ameneh; Etemad, Leila; Moshiri, Mohammad; Moallem, Seyed Adel; Jafarian, Amir Hossein; Hadizadeh, Farzin; Seifi, Mahmoud

    2017-01-01

    Objective(s): The increasing use of methamphetamine (METH) in the last decades has made it the second most abused drug. Advancs in the area of intravenous lipid emulsion (ILE) have led to its potential application in the treatment of poisoning. The present study aims to investigate the potential role of ILE as an antidote for acute METH poisoning. Materials and Methods: Two groups of six male rats were treated by METH (45 mg/kg), intraperitoneally. Five to seven min later, they received an infusion of 18.6 ml/kg ILE 20% through the tail vein or normal saline (NS). Locomotor and behavioral activity was assessed at different time after METH administration. Body temperature and survival rates were also evaluated. Brain and internal organs were then removed for histological examination and TUNEL assay. Results: ILE therapy for METH poisoning in rats could prevent rats mortalities and returned the METH-induced hyperthermia to normal rates (P<0.05). ILE reduced freezing and stereotyped behaviors and increased rearing responses (P<0.05). Locomotor activity also returned to control levels especially during the last hours of the experiment. ILE administration decreased the prevalence of pulmonary emphysema in the lungs (P<0.05 and P<0.01) and percentages of TUNEL positive cells in the brain (P<0.05), in comparison with the control group. Conclusion: ILE could reduce the severity of METH- induced toxicity as well as mortality rate in the animals. Intravenous infusion of lipid emulsion may save the life of patients with acute METH intoxication who do not respond to standard initial therapy. PMID:28293389

  5. Improving cabazitaxel chemical stability in parenteral lipid emulsions using cholesterol.

    PubMed

    Shao, Yanjie; Zhang, Chungang; Yao, Qing; Wang, Yueqi; Tian, Bin; Tang, Xing; Wang, Yanjiao

    2014-02-14

    Intravenous lipid emulsions of cabazitaxel (CLEs) with a high stability were prepared by adding cholesterol (CH) to provide a new and more suitable delivery system for its administration. The factors affecting CLEs, such as the solubility of cabazitaxel in various oils, different kinds of lecithin, pH, different types of oil phases, and different concentrations of lipoid E80®, CH and poloxamer 188 were investigated systematically. The degradation of cabazitaxel in aqueous solution and lipid emulsion both followed pseudo first-order kinetics. A degradation mechanism was suggested by the U-shaped pH-rate profile of cabazitaxel. A formulation containing 0.5% (w/v) CH and another formulation without CH were made to investigate the protective influence of CH on the chemical stability of CLEs. The activation energy of the two formulations was calculated to be 65.74±6.88 and 54.24±1.43 kJ/mol (n=3), respectively. Compared with the untreated CH, the shelf-life of cabazitaxel with added CH was longer, namely 134.0±23.4 days versus 831.4±204.4 days (n=3) at 4 °C. This indicates that the addition of CH significantly improved the lifetime of cabazitaxel in intravenous lipid emulsions. The hydrogen bonding that takes place between cabazitaxel and CH accounts for the protective effect of CH on the chemical stability of CLEs in two ways: preventing cabazitaxel from leaking and hydrolyzing in aqueous solution and hindering hydrolysis in the oil phase. Finally, the hypothesis was confirmed by LC/TOFMS and Fourier-transform infrared-spectroscopy. As a result, CLEs were obtained successfully by the addition of CH and were stable enough to allow further research.

  6. High temperature structural, polymeric foams from high internal emulsion polymerization

    SciTech Connect

    Hoisington, M.A.; Duke, J.R.; Apen, P.G.

    1996-02-01

    In 1982, a high internal phase emulsion (HIPE) polymerization process to manufacture microcellular, polymeric foam systems was patented by Unilever. This patent discloses a polymerization process that occurs in a water-in-oil emulsion in which the water represents at least 76% of the emulsion by volume. The oil phase consists of vinyl monomers such as styrene and acrylates that are crosslinked by divinyl monomers during polymerization. After polymerization and drying to remove the water phase, the result is a crosslinked polymer foam with an open cell microstructure that is homogeneous throughout in terms of morphology, density, and mechanical properties. Since 1982, numerous patents have examined various HIPE polymerized foam processing techniques and applications that include absorbents for body fluids, cleaning materials, and ion exchange systems. All the published HIPE polymerized foams have concentrated on materials for low temperature applications. Copolymerization of styrene with maleic anhydride and N-substituted maleimides to produce heat resistant thermoplastics has been studied extensively. These investigations have shown that styrene will free radically copolymerize with N-substituted maleimides to create an alternating thermoplastic copolymer with a Tg of approximately 200{degrees}C. However, there are many difficulties in attempting the maleimide styrene copolymerization in a HIPE such as lower polymerization temperatures, maleimide solubility difficulties in both styrene and water, and difficulty obtaining a stable HIPE with a styrene/maleimide oil phase. This work describes the preparation of copolymer foams from N-ethylmaleimide and Bis(3-ethyl-5-methyl-4-maleimide-phenyl)methane with styrene based monomers and crosslinking agents.

  7. Mango butter emulsion gels as cocoa butter equivalents: physical, thermal, and mechanical analyses.

    PubMed

    Sagiri, Sai S; Sharma, Vijeta; Basak, Piyali; Pal, Kunal

    2014-11-26

    The search for cocoa butter equivalents in food and pharmaceutical industries has been gaining importance. In the present study, mango butter was explored as cocoa butter equivalent. Aqueous gelatin solution (20% w/w) containing cocoa butter and mango butter water-in-oil (fat) type emulsion gels were prepared by hot emulsification method. XRD and DSC melting profiles suggested the presence of unstable polymorphic forms (α and β') of fats in the emulsion gels. The crystal size and solid fat content analyses suggested that the presence of aqueous phase might have hindered the transformation of unstable polymorphic forms to stable polymorphic form (β) in the emulsion gels. Fat crystals in the emulsion gels were formed by instantaneous nucleation via either uni- or bidimensional growth (Avrami analysis). The viscoelastic nature of the emulsion gels was evaluated by modified Peleg's analysis (stress relaxation study). Results inferred that the physical, thermal, and mechanical properties of mango butter emulsion gels are comparable to those of cocoa butter emulsion gels. On the basis of preliminary studies, it was suggested that the mango butter emulsion gels may have potential to be used as cocoa butter equivalents.

  8. Premature detonation of an NH₄NO₃ emulsion in reactive ground.

    PubMed

    Priyananda, Pramith; Djerdjev, Alex M; Gore, Jeff; Neto, Chiara; Beattie, James K; Hawkett, Brian S

    2015-01-01

    When NH4NO3 emulsions are used in blast holes containing pyrite, they can exothermally react with pyrite, causing the emulsion to intensively heat and detonate prematurely. Such premature detonations can inflict fatal and very costly damages. The mechanism of heating of the emulsions is not well understood though such an understanding is essential for designing safe blasting. In this study the heating of an emulsion in model blast holes was simulated by solving the heat equation. The physical factors contributing to the heating phenomenon were studied using microscopic and calorimetric methods. Microscopic studies revealed the continuous formation of a large number of gas bubbles as the reaction progressed at the emulsion-pyrite interface, which made the reacting emulsion porous. Calculations show that the increase in porosity causes the thermal conductivity of a reacting region of an emulsion column in a blast hole to decrease exponentially. This large reduction in the thermal conductivity retards heat dissipation from the reacting region causing its temperature to rise. The rise in temperature accelerates the exothermic reaction producing more heat. Simulations predict a migration of the hottest spot of the emulsion column, which could dangerously heat the primers and boosters located in the blast hole.

  9. Determination of emulsion explosives with Span-80 as emulsifier by gas chromatography-mass spectrometry.

    PubMed

    Tian, Fei-Fei; Yu, Jing; Hu, Jia-Hong; Zhang, Yong; Xie, Meng-Xia; Liu, Yuan; Wang, Xiang-Feng; Liu, Hai-Ling; Han, Jie

    2011-06-03

    A novel approach for identification and determination of emulsion explosives with Span-80 (sorbitol mono-oleate) as the emulsifier and their postblast residues by gas chromatography-mass spectrometry (GC-MS) has been developed. 24 kinds of emulsion explosives collected have been processed by transesterification reaction with metholic KOH solution and the emulsifier has turned into methyl esters of fatty acids. From the peak area ratios of their methyl esters, most of these emulsion explosives can be differentiated. In order to detect the postblast residues of emulsion explosives, the sorbitols in the emulsifier Span-80 obtained after transesterification reaction have been further derivatized by silylation reaction with N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% trimethylchlorosilane (TMCS) as the derivatizing reagent. The derivatization conditions were optimized and the derivatives were determined by GC-MS. The results showed that the silylation derivatives of sorbitol and it isomers, combined with hydrocarbon compounds and methyl esters of fatty acids, were the characteristic components for identification of the emulsion explosives. The established approach was applied to analyze the postblast residues of emulsion explosives. It has been found that the method was sensitive and specific, especially when detecting the derivatives of sorbitol and its isomers by GC-MS in selecting ion mode. The information of the characteristic components can help probe the origin of the emulsion explosives and providing scientific evidences and clues for solving the crimes of the emulsion explosive explosion.

  10. Effects of diesel engine speed and water content on emission characteristics of three-phase emulsions.

    PubMed

    Lin, Cherng-Yuan; Wang, Kuo-Hua

    2004-01-01

    The effects of water content of three-phase emulsions and engine speed on the combustion and emission characteristics of diesel engines were investigated in this study. The results show that a larger water content of water-in oil (W/O) and oil-in-water-in-oil (O/W/O) emulsion caused a higher brake specific fuel consumption (bsfc) value and a lower O2, as well as a lower NOx emission, but a larger CO emission. The increase in engine speed resulted in an increase of bsfc, exhaust gas temperature, fuel-to-air ratio, CO2 emission and a decrease of NOx, CO emission, and smoke opacity. Because of the physical structural differences, the three-phase O/W/O emulsions were observed to produce a higher exhaust gas temperature, a higher emulsion viscosity and a lower CO emission, in comparison with that of the two-phase W/O emulsion. In addition, the use of W/O emulsions with water content larger than 20% may cause diesel engines to shut down earlier than those running on O/W/O emulsions with the same water content. Hence, it is suggested that the emulsions with water content larger than 20% are not suitable for use as alternative fuel for diesel engines.

  11. Microencapsulation using an oil-in-water-in-air 'dry water emulsion'.

    PubMed

    Carter, Benjamin O; Weaver, Jonathan V M; Wang, Weixing; Spiller, David G; Adams, Dave J; Cooper, Andrew I

    2011-08-07

    We describe the first example of a tri-phasic oil-in-water-in-air 'dry water emulsion'. The method combines highly stable oil-in-water emulsions prepared using branched copolymer surfactants, with aqueous droplet encapsulation using 'dry water' technology.

  12. Influence of PEG-12 Dimethicone addition on stability and formation of emulsions containing liquid crystal.

    PubMed

    Andrade, F F; Santos, O D H; Oliveira, W P; Rocha-Filho, P A

    2007-06-01

    Oil/water emulsions, containing liquid crystals, were developed employing Andiroba oil, PEG-12 Dimethicone and Crodafos CES. It was evaluated the influence of silicone surfactants on the emulsions stability and on the formation of liquid crystalline phases and therefore, physicochemical characteristics, such as rheology and zeta potential, were evaluated. Emulsions were prepared by the emulsions phase inversion method. All the formulations presented lamellar liquid crystalline phases. The PEG-12 Dimethicone addition did not change microscopically the liquid crystalline phases. The emulsions containing silicone demonstrated lower viscosity than those without the additive. This is an important feature, as the silicone did not change the rheological profile; however, the addition of silicone still can be used as a viscosity controller. The formulations had their viscosity increased 15 and 150 days after their preparation. This characteristic shows that the emulsions have their organization increased along the storing time. In the analysis of zeta potential, we could verify that all formulations presented negative values between -39.7 and -70.0 mV. Within this range of values, the emulsion physical stability is high (Fig. 10). It was concluded that the addition of PEG-12 Dimethicone kept the liquid crystalline phase of the emulsion obtained with Crodafos CES, influencing in a positive way in the system stability.

  13. Development and characterization of a emulsions containing purple rice bran and brown rice oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aims of this study were to characterize purple rice bran oil (PRBO) as extracted from the bran, and to produce and characterize a nano-emulsion containing purple rice bran oil. An emulsion was prepared using PRBO (10%), sodium caseinate (5%) and water (85%). The mixture was sonicated followed ...

  14. Surfactant effects on bio-based emulsions used as lubrication fluids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The successful formulation of a lubricating emulsion requires carefully balancing the mixture of base oil, water and a plethora of additives. The factors that affect the performance of lubrication emulsions range from the macroscopic stability to the microscopic surface properties of the base oil. ...

  15. Stable emulsion copolymers of acrylamide and ammonium acrylate for use in enhanced oil recovery

    SciTech Connect

    Frank, S.; Coscia, A.T.; Schmitt, J.M.

    1984-03-27

    There is provided a process for recovering oil from oil bearing formations employing the use of a water treating medium, which medium comprises the inclusion of a novel stable emulsion copolymer of acrylamide and ammonium acrylate as well as the emulsion copolymer per se.

  16. 21 CFR 524.802 - Enrofloxacin and silver sulfadiazine otic emulsion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Enrofloxacin and silver sulfadiazine otic emulsion... ANIMAL DRUGS § 524.802 Enrofloxacin and silver sulfadiazine otic emulsion. (a) Specifications. Each milliliter contains 5 milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor. See No....

  17. Optimization of folic acid nano-emulsification and encapsulation by maltodextrin-whey protein double emulsions.

    PubMed

    Assadpour, Elham; Maghsoudlou, Yahya; Jafari, Seid-Mahdi; Ghorbani, Mohammad; Aalami, Mehran

    2016-05-01

    Due to susceptibility of folic acid like many other vitamins to environmental and processing conditions, it is necessary to protect it by highly efficient methods such as micro/nano-encapsulation. Our aim was to prepare and optimize real water in oil nano-emulsions containing folic acid by a low energy (spontaneous) emulsification technique so that the final product could be encapsulated within maltodextrin-whey protein double emulsions. A non ionic surfactant (Span 80) was used for making nano-emulsions at three dispersed phase/surfactant ratios of 0.2, 0.6, and 1.0. Folic acid content was 1.0, 2.0, and 3.0mg/mL of dispersed phase by a volume fraction of 5.0, 8.5, and 12%. The final optimum nano-emulsion formulation with 12% dispersed phase, a water to surfactant ratio of 0.9 and folic acid content of 3mg/mL in dispersed phase was encapsulated within maltodextrin-whey protein double emulsions. It was found that the emulsification time for preparing nano-emulsions was between 4 to 16 h based on formulation variables. Droplet size decreased at higher surfactant contents and final nano-emulsions had a droplet size<100 nm. Shear viscosity was higher for those formulations containing more surfactant. Our results revealed that spontaneous method could be used successfully for preparing stable W/O nano-emulsions containing folic acid.

  18. Reduction of lipid oxidation by formation of caseinate-oil-oat gum emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentration of oat gum, though important for formation of stable emulsion, has no effect on oxidation of Omega 3 oil; this is most prominent in fish-oil based Omega 3 oil. The optimal concentration of oat gum is about 0.2% wt for emulsion stability and visual appearance. We found that concentr...

  19. Impact of parenteral lipid emulsions on the metabolomic phenotype in preterm TPN-fed piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids in parenteral nutrition provide essential fatty acids and are a major source of energy for hospitalized neonates. Intralipid (IL) is the only approved lipid emulsion in the U.S, but new generation emulsions include Omegaven (OV) and SMOFlipid (SL). There are no studies describing the metaboli...

  20. A double-emulsion microfluidic platform for in vitro green fluorescent protein expression

    NASA Astrophysics Data System (ADS)

    Wu, N.; Oakeshott, J. G.; Easton, C. J.; Peat, T. S.; Surjadi, R.; Zhu, Y.

    2011-05-01

    Microfluidic droplet technology has gained popularity due to the advantages over conventional emulsion techniques and capabilities for a wide range of applications. In this paper, the development of a simple microfluidic-based double-emulsion system is reported. Such a system could be potentially used for in vitro protein synthesis. The system involves a two-step process to make water-in-oil-in-water (W/O/W) emulsions. A PMMA microchip is used for the formation of water-in-oil (W/O) single-emulsion droplets. Then, the single-emulsion droplets are transported to a PDMS/glass microchip to make the W/O/W double-emulsion droplets. The system was first characterized by detecting fluorescein sodium salt as a model dye in the internal aqueous droplets using laser-induced fluorescence. The effect of the flow rates of the internal aqueous phase and outer continuous aqueous phase on the formation of the double-emulsion droplets is investigated to provide information for system optimization. On-chip storage of double-emulsion droplets is also investigated to allow for protein synthesis from a PCR-generated DNA template using either commercial in vitro transcription and translation kits or crude Escherichia coli S30 extracts. In vitro expression of the green fluorescent protein is successfully demonstrated in this system.

  1. Development of neutron measurement in high gamma field using new nuclear emulsion

    SciTech Connect

    Kawarabayashi, J.; Ishihara, K.; Takagi, K.; Tomita, H.; Iguchi, T.; Naka, T.; Morishima, K.; Maeda, S.

    2011-07-01

    To precisely measure the neutron emissions from a spent fuel assembly of a fast breeder reactor, we formed nuclear emulsions based on a non-sensitized Oscillation Project with Emulsion tracking Apparatus (OPERA) film with AgBr grain sizes of 60, 90, and 160 nm. The efficiency for {sup 252}Cf neutron detection of the new emulsion was calculated to be 0.7 x 10{sup -4}, which corresponded to an energy range from 0.3 to 2 MeV and was consistent with a preliminary estimate based on experimental results. The sensitivity of the new emulsion was also experimentally estimated by irradiating with 565 keV and 14 MeV neutrons. The emulsion with an AgBr grain size of 60 nm had the lowest sensitivity among the above three emulsions but was still sensitive enough to detect protons. Furthermore, the experimental data suggested that there was a threshold linear energy transfer of 15 keV/{mu}m for the new emulsion, below which no silver clusters developed. Further development of nuclear emulsion with an AgBr grain size of a few tens of nanometers will be the next stage of the present study. (authors)

  2. 78 FR 58318 - Clinical Trial Design for Intravenous Fat Emulsion Products; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ... HUMAN SERVICES Food and Drug Administration Clinical Trial Design for Intravenous Fat Emulsion Products... ``Clinical Trial Design for Intravenous Fat Emulsion Products.'' This workshop will provide a forum to discuss trial design of clinical trials intended to support registration of intravenous fat...

  3. Adding reagent to droplets with controlled rupture of encapsulated double emulsions

    PubMed Central

    Sciambi, Adam; Abate, Adam R.

    2013-01-01

    We present a method to add reagent to microfluidic droplets by enveloping them as a double emulsions in reagent-filled droplets and then rupturing them with an electric field. When the double emulsions rupture, they release their contents into the enveloping droplets, ensuring mixing with reagent while limiting cross-droplet contamination. PMID:24404045

  4. Impact of parenteral lipid emulsions on metabolomic phenotype in preterm TPN-fed piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipids in parenteral nutrition provide essential fatty acids and are a major source of energy for hospitalized neonates. Intralipid (IL) is the only approved lipid emulsion in the US, but new generation emulsions include Omegaven (OV) and SMOFlipid (SL). There are no studies describing the metabolit...

  5. Research News: Emulsion Liquid Membrane Extraction in a Hollow-Fiber Contactor

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.; Hu, Shih-Yao

    2000-01-01

    This article describes how ELMs (emulsion liquid membranes) can be used for extraction. The article addresses the disadvantages of ELM extraction in a stirred contactor, and the advantages of SELMs (supported emulsion liquid membranes). The introduction of the article provides background information on liquid-liquid solvent extraction and dispersion-free solvent extraction.

  6. Heavy-ion physics with the ALICE experiment at the CERN Large Hadron Collider.

    PubMed

    Schukraft, J

    2012-02-28

    After close to 20 years of preparation, the dedicated heavy-ion experiment A Large Ion Collider Experiment (ALICE) took first data at the CERN Large Hadron Collider (LHC) accelerator with proton collisions at the end of 2009 and with lead nuclei at the end of 2010. After a short introduction into the physics of ultra-relativistic heavy-ion collisions, this article recalls the main design choices made for the detector and summarizes the initial operation and performance of ALICE. Physics results from this first year of operation concentrate on characterizing the global properties of typical, average collisions, both in proton-proton (pp) and nucleus-nucleus reactions, in the new energy regime of the LHC. The pp results differ, to a varying degree, from most quantum chromodynamics-inspired phenomenological models and provide the input needed to fine tune their parameters. First results from Pb-Pb are broadly consistent with expectations based on lower energy data, indicating that high-density matter created at the LHC, while much hotter and larger, still behaves like a very strongly interacting, almost perfect liquid.

  7. Comparison of Measured and Simulated Albedo Signals in the ATIC Experiment

    NASA Technical Reports Server (NTRS)

    Zatsepin, V. I.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G. L.; Batkov, K. E.; Chang, J.; Christl, M.; Fazely, A. R.; Ganel, O.; Gunasingha, R. M.

    2003-01-01

    Albedo, radiation backscattered from an interaction and from the subsequent shower development, provides a 'background' for calorimeter experiments. In ATIC (Advanced Thin Ionization Calorimeter), a balloon borne instrument to measure cosmic ray composition and energy spectra for elements from hydrogen to iron from 30 GeV to near 100 TeV, a fully active BGO calorimeter follows a carbon interaction target and scintillator holdoscopes. The first detector is a silicon matrix constructed of 4480 individual silicon pixels, each 2 cm x 1.5 cm, that provide a measurement of the charge of the primary particle in the presence of albedo. ATIC had two successful balloon flights in Antarctica: from 28 Dec 2000 to 13 Jan 2001 (ATIC-1) and from 29 Dec 2002 to 18 Jan 2003 (ATIC-2). A comparison of albedo signals in the silicon matri:x in ATIC-1 experiment with simulations performed using the GEANT 3.21 code and the QGSM event generator for nucleus-nucleus interactions is presented.

  8. The use of IV lipid emulsion for lipophilic drug toxicities.

    PubMed

    Kaplan, Amy; Whelan, Megan

    2012-01-01

    IV lipid emulsion (ILE) therapy is emerging as a potential antidote for lipophilic drug toxicities in both human and veterinary medicine. ILE has already gained acceptance in human medicine as a treatment of local anesthetic systemic toxicity, but its mechanism of action, safety margins, and standardized dosing information remains undetermined at this time. Experimental and anecdotal use of ILE in the human and veterinary literature, theorized mechanisms of action, current dosing recommendations, potential adverse effects, and indications for use in human and veterinary emergency medicine are reviewed herein.

  9. Preparation of drug nanoparticles by emulsion evaporation method

    NASA Astrophysics Data System (ADS)

    Hoa, Le Thi Mai; Chi, Nguyen Tai; Triet, Nguyen Minh; Thanh Nhan, Le Ngoc; Mau Chien, Dang

    2009-09-01

    Polymeric drug nanoparticles were prepared by emulsion solvent evaporation method. In this study, prepared the polymeric drug nanoparticles consist of ketoprofen and Eudragit E 100. The morphology structure was investigated by scanning electron microscopy (SEM). The interactions between the drug and polymer were investigated by Fourier transform infrared spectroscopy (FTIR). The size distribution was measured by means of Dynamic Light Scattering. The nanoparticles have an average size of about 150 nm. The incorporation ability of drugs in the polymeric nanoparticles depended on the integration between polymer and drug as well as the glass transition temperature of the polymer.

  10. Size limit for particle-stabilized emulsion droplets under gravity.

    PubMed

    Tavacoli, J W; Katgert, G; Kim, E G; Cates, M E; Clegg, P S

    2012-06-29

    We demonstrate that emulsion droplets stabilized by interfacial particles become unstable beyond a size threshold set by gravity. This holds not only for colloids but also for supracolloidal glass beads, using which we directly observe the ejection of particles near the droplet base. The number of particles acting together in these ejection events decreases with time until a stable acornlike configuration is reached. Stability occurs when the weight of all remaining particles is less than the interfacial binding force of one particle. We also show the importance of the curvature of the droplet surface in promoting particle ejection.

  11. Vorticity alignment and negative normal stresses in sheared attractive emulsions.

    PubMed

    Montesi, Alberto; Peña, Alejandro A; Pasquali, Matteo

    2004-02-06

    Attractive emulsions near the colloidal glass transition are investigated by rheometry and optical microscopy under shear. We find that (i) the apparent viscosity eta drops with increasing shear rate, then remains approximately constant in a range of shear rates, then continues to decay; (ii) the first normal stress difference N1 transitions sharply from nearly zero to negative in the region of constant shear viscosity; and (iii) correspondingly, cylindrical flocs form, align along the vorticity, and undergo a log-rolling movement. An analysis of the interplay between steric constraints, attractive forces, and composition explains this behavior, which seems universal to several other complex systems.

  12. Effect of inorganic additives on solutions of nonionic surfactants V: Emulsion stability.

    PubMed

    Schott, H; Royce, A E

    1983-12-01

    Electrolytes often break emulsions to which they were added as active ingredients, adjuvants, or impurities. The stability of oil-in-water emulsions containing octoxynol 9 NF as the emulsifier and various added electrolytes was investigated by measuring droplet size, turbidity, and oil separation on storage at various temperatures and in a centrifugal field at 25 degrees. Electrolytes were added to hexadecane emulsions after emulsification (direct addition); alternatively, hexadecane was emulsified in octoxynol 9-electrolyte mixtures (reverse addition). Xylene emulsions were prepared by direct addition only. Hexadecane emulsions containing 0.10% octoxynol 9 were considerably more stable than xylene emulsions containing 0.60% because the surfactant is practically insoluble in hexadecane, but miscible in all proportions with xylene. An emulsifier soluble in the disperse phase as well as the continuous phase evidently forms less stable interfacial films. The electrolytes investigated were sulfuric and hydrochloric acids, magnesium nitrate, and aluminum nitrate, which salt octoxynol 9 in by complexation between its ether groups and their cations; sodium thiocyanate, which salts the surfactant in by destructuring water; and sodium chloride and sodium sulfate, which salt octoxynol 9 out. The addition of these electrolytes at concentrations up to 2 or 3 m to hexadecane emulsions produced fast and extensive creaming, little or no flocculation, no coalescence, and only minor changes in droplet size or turbidity on storage at room temperature. The extent of coalescence during centrifugation was actually reduced by the additives. Such stability is unusual. Droplet size and turbidity depended mainly on octoxynol 9 concentration. The greatest decrease in the former and increase in the latter occurred when the concentration was increased from 0.10 to approximately 0.4%. All emulsions became slightly coarser on storage at 25 degrees. Stability at 50 degrees was impaired by

  13. Prevention of topical and ocular oxidative stress by positively charged submicron emulsion.

    PubMed

    Benita, S

    1999-05-01

    A positively charged submicron emulsion with zeta potential values ranging from 35 to 45 mV and mean droplet size around 150-250 nm has recently been developed and characterized. This formulation is based on three surface-active agents, an egg yolk phospholipid mixture, poloxamer 188, and stearylamine, a cationic lipid with a pKa of 10.6. The emulsion toxicity was evaluated in three animal studies. The results of the ocular tolerance study in the rabbit eye indicated that hourly administration of one droplet of the positively charged emulsion vehicle was well tolerated without any toxic or inflammatory response to the ocular surface during the five days of the study. No marked acute toxicity was observed when 0.6 mL of positively charged emulsion was injected intravenously to BALB/c mice. Furthermore, no difference was noted between this group of animals and the group injected with the marketed and clinically well accepted negatively charged Intralipid emulsion. These observations were further confirmed in a four week toxicity study following intravenous administration to rats of 1 mL/kg of the positively charged emulsion as compared to Intralipid. No toxic effect was noted in any of the various organs examined, whereas the results of the hematological and blood chemistry tests remained in the normal range for both emulsions, confirming the preliminary safety study findings. In addition, it was demonstrated by means of a non-invasive technique that alpha-tocopherol positively charged emulsions prevented oxidative damage in rat skin subjected to UVA irradiation. The intrinsic ability of positively charged emulsified oil droplets to protect against reactive oxygen species cannot be excluded, and could act synergistically with the antioxidant alpha-tocopherol itself. The effect of blank and piroxicam positively charged emulsions on rabbit eye following alkali burn was also evaluated. The blank emulsion showed a very rapid healing rate during the first three days with

  14. Physical properties of a frozen yogurt fortified with a nano-emulsion containing purple rice bran oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to develop and evaluate a frozen yogurt (FY) fortified with a nano-emulsion containing purple rice bran oil (NPRBO). A nano-emulsion with a droplet size range of 150-300 nm was produced by sonication followed by ultra-shear homogenization. The nano-emulsion was mi...

  15. Antifungal activity against Candida albicans of starch Pickering emulsion with thymol or amphotericin B in suspension and calcium alginate films.

    PubMed

    Cossu, Andrea; Wang, Min S; Chaudhari, Amol; Nitin, Nitin

    2015-09-30

    Conventional antifungal treatments against Candida albicans in the oral cavity often result in increased cytotoxicity. The goal of this study was to determine the potential of starch Pickering emulsion as a delivery vehicle for an antifungal natural phenolic compound such as thymol in simulated saliva fluid (SSF) compared to amphotericin B. An oil-in-water (o/w) emulsion was stabilized using starch particles. Physical stability of the emulsion and disruption induced by α-amylase activity in SSF was evaluated. Encapsulated thymol in o/w emulsion was compared to encapsulated amphotericin B for antifungal activity against C. albicans in suspension using emulsions or zone inhibition assay on agar plates using emulsions dispersed in alginate films. Results showed that the emulsions were stable for at least three weeks. Digestion of the emulsion by α-amylase led to coalescence of emulsion droplets. The antifungal activity of thymol and amphotericin B in emulsion formulation was enhanced upon incubation with α-amylase. Results from the zone inhibition assay demonstrated efficacy of the emulsions dispersed in alginate films. Interestingly, addition of α-amylase to the alginate films resulted in a decreased inhibitory effect. Overall, this study showed that starch Pickering emulsions have a potential to deliver hydrophobic antifungal compounds to treat oral candidiasis.

  16. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... disulfide limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63.500 Protection... limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators of sources subject to this subpart producing styrene butadiene rubber using an emulsion process shall operate the...

  17. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... disulfide limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63.500 Protection... limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators of sources subject to this subpart producing styrene butadiene rubber using an emulsion process shall operate the...

  18. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... disulfide limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63.500 Protection... limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators of sources subject to this subpart producing styrene butadiene rubber using an emulsion process shall operate the...

  19. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... disulfide limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63.500 Protection... limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators of sources subject to this subpart producing styrene butadiene rubber using an emulsion process shall operate the...

  20. Influence of droplet size on the antioxidant activity of rosemary extract loaded oil-in-water emulsions in mixed systems.

    PubMed

    Erdmann, Martin E; Zeeb, Benjamin; Salminen, Hanna; Gibis, Monika; Lautenschlaeger, Ralf; Weiss, Jochen

    2015-03-01

    The influence of droplet size on the antioxidant activity of oil-in-water emulsions loaded with rosemary extract in mixed emulsion systems was investigated. Firstly, differently sized hexadecane-in-water model emulsions (10% (w/w) hexadecane, 2% (w/w) Tween 80, pH 5 or 7) containing 4000 ppm rosemary extract in the oil phase or without added antioxidant were prepared using a high shear blender and/or high-pressure homogenizer. Secondly, emulsions were mixed with fish oil-in-water emulsions (10% (w/w) fish oil, 2% (w/w) Tween 80, pH 5 or 7) at a mixing ratio of 1 : 1. Optical microscopy and static light scattering measurements indicated that emulsions were physically stable for 21 days, except for the slight aggregation of emulsions with a mean droplet size d₄₃ of 4500 nm. The droplet size of hexadecane-in-water emulsions containing rosemary extract had no influence on the formation of lipid hydroperoxides at pH 5 and 7. Significantly lower concentrations of propanal were observed for the emulsions loaded with rosemary extract with a mean droplet size d₄₃ of 4500 nm from day 12 to 16 at pH 7. Finally, hexadecane-in-water emulsions containing rosemary extract significantly retarded lipid oxidation of fish oil-in-water emulsions in mixed systems, but no differences in antioxidant efficacy between the differently sized emulsions were observed at pH 5.