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Sample records for emulsion chamber experiments

  1. 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.

  2. 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.

  3. Large area emulsion chamber experiments for the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Parnell, T. A.

    1985-01-01

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

  4. Japan - USSR joint emulsion chamber experiment at Pamir

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The results are presented for the systematic measurement of cosmic ray showers in the first carbon chamber of Japan-USSR joint experiment at Pamir Plateau. The intensity and the energy distribution of electromagnetic particles, of hadrons and of families are in good agreement with the results of other mountain experiment if the relative error in energy estimation is taken into consideration.

  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. 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.

  7. 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.

  8. 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.; Lu, S. L.; Su, S.; Xue, Y. G.; Wang, C. R.; Huo, A. X.; Wang, Y. X.; 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.

  9. 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.

  10. Electromagnetic Shower Reconstruction in Emulsion Cloud Chamber

    NASA Astrophysics Data System (ADS)

    Esposito, L. S.

    2006-04-01

    Atmospheric neutrino data from the MACRO, Soudan II and Super-Kamiokande experiments are consistent with the hypothesis of νμ → ντ oscillations. The OPERA experiment aims to prove definitively this hypothesis with the direct observation of ντ neutrinos in the νμ beam produced at CERN (CNGS). The apparatus, in construction at the Gran Sasso Underground Laboratory, is equipped with electronic detectors and a sensitive target. The target is highly segmented in units, bricks, composed of alternate nuclear emulsion plates and lead sheets. An algorithm to reconstruct electromagnetic showers in a brick was developed. The algorithm was optimized using experimental data from 1, 3 and 6 GeV electron exposures and cross-checked with detailed Monte Carlo simulations. Finally, a neural network was used as electron/pion separator.

  11. Super-family P2 C-96-125 observed by Japan-URSS Joint Emulsion Chamber Experiment

    NASA Technical Reports Server (NTRS)

    Shibuya, E. H.

    1985-01-01

    A detailed description of the event detected in the second chamber of Japan-URSS Collaboration is presented. A preliminary description was already published and from that time a careful microscopic scanning was carried out.

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

    NASA Technical Reports Server (NTRS)

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

    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.

  13. Numerical analysis of electromagnetic cascades in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Plyasheshnikov, A. V.; Vorobyev, K. V.

    1985-01-01

    A new calculational scheme of the Monte Carlo method assigned for the investigation of the development of high and extremely high energy electromagnetic cascades (EMC) in the matter was elaborated. The scheme was applied to the analysis of angular and radial distributions of EMC electrons in the atmosphere. By means of this scheme the EMC development in dense medium is investigated and some preliminary data are presented on the behavior of EMC in emulsion chambers. The results of more detailed theoretical analysis of the EMC development in emulsion chambers are discussed.

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

    NASA Astrophysics Data System (ADS)

    Mukhamedshin, R. A.

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

  15. High energy primary electron spectrum observed by the emulsion chamber

    NASA Technical Reports Server (NTRS)

    Nishimura, J.; Fujii, M.; Aizu, H.; Hiraiwa, N.; Taira, T.; Kobayashi, T.; Niu, K.; Koss, T. A.; Lord, J. J.; Golden, R. L.

    1978-01-01

    A detector of the emulsion chamber type is used to measure the energy spectrum of cosmic-ray electrons. Two large emulsion chambers, each having an area of 40 by 50 sq cm, are exposed for about 25.5 hr at an average pressure altitude of 3.9 mbar. About 500 high-energy cascades (no less than about 600 GeV) are detected by searching for dark spots on the X-ray films. A power-law energy dependence formula is derived for the spectrum of primary cosmic-ray electrons in the energy region over 100 GeV. The results are in good agreement with the transition curves obtained previously by theoretical and Monte Carlo calculations.

  16. 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.; Holynski, R.; Jurak, A.; Hayashi, T.; Iwai, J.; Jones, W. V.

    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.

  17. Lateral distortions of electromagnetic cascades in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Porter, L. G.; Levit, L. B.; Jones, W. V.; Huggett, R. W.; Barrowes, S. C.

    1975-01-01

    Electromagnetic cascades in a lead-emulsion chamber have been studied to determine the effect of air gaps on the upstream sides of the emulsions. Such air gaps cause a change in the form of the radial distribution of electron tracks, making cascades appear older and giving incorrect energy estimates. The number of tracks remaining within a radius r was found to vary as exp(-g/G), where g is the gap thickness. The characteristic gap thickness in mm is G = 3.04 + 1.30 ln (Err per GeV per sq mm) where E is the energy of the initiating gamma ray. Use of this relation provides a significant correction to cascade-energy estimates and allows one to calculate the effect of different gap thicknesses on the energy threshold for visual detection of cascades.

  18. High energy electrons beyond 100 GEV observed by emulsion chamber

    NASA Technical Reports Server (NTRS)

    Nishimura, J.; Fujii, M.; Yoshida, A.; Taira, T.; Aizu, H.; Nomura, Y.; Kobayashi, T.; Kazuno, M.; Nishio, A.; Golden, R. L.

    1986-01-01

    Much efforts have been expended to observe the spectrum of electrons in the high energy region with large area emulsion chambers exposed at balloon altitudes, and now 15 electrons beyond 1 TeV have been observed. The observed integral flux at 1 TeV is (3.24 + or - 0.87)x10(-5)/sq m sec sr. The statistics of the data around a few hundred GeV are also improving by using new shower detecting films of high sensitivity. The astrophysical significance of the observed spectrum are discussed for the propagation of electrons based on the leaky box and the nested leaky box model.

  19. The response of a scintillation counter below an emulsion chamber to heavy nucleus interactions in the chamber

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    In 1982 a hybrid electronic counter-emulsion chamber experiment was flown on a balloon to study heavy nucleus interactions in the 20 to approximately 100 GeV/AMU energy range. A gas Cerenkov counter, two solid Cerenkov counters, and a proportional counter hodoscope gave the primary energy, the primary charge and the trajectory of the particles, respectively. Using the trajectory information cosmic ray nuclei of Z 10 were found reliably and efficiently, and interaction characteristics of the Fe group nuclei were measured in the chamber. A plastic scintillator below the emulsion chamber responded to showers resulting from interactions in the chamber and to noninteracting nuclei. Data on the response of the counter have been compared with simulations of hadronic-electromagnetic cascades to derive the average neutral energy fraction released by the heavy interactions, and to predict the performance of this kind of counter at higher energies. For the interacting events of highest produced particles multiplicity comparison between various simulations and the shower counter signal have been made.

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  1. Experiment S009: Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

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

  2. Nuclear Emulsion - Skylab Experiment S009

    NASA Technical Reports Server (NTRS)

    1970-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  4. OPERA experiment and its releted emulsion techniques

    SciTech Connect

    Ariga, Akitaka

    2008-02-21

    The OPERA experiment is designed to clarify neutrino oscillation by detecting appearance of {nu}{sub {tau}} in pure {nu}{sub {mu}} beam through a long baseline method (CNGS beam from cern to the Gran Sasso laboratory). The key technique is the use of emulsion films and their scanning. We developed a new high speed scanning system with speed of 50 cm{sup 2}/h and it was successfully demonstrated in 2006 CNGS commissioning. The new scanning system is not only meant for the OPERA experiment, but it has large potential of applications. For example, measurement of {nu}{sub e} with strong separation power against {pi}{sup 0}. Or a compact emulsion spectrometer for future neutrino experiments.

  5. 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.

  6. 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.

  7. 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.

  8. Emulsion chamber with big radiation length for detecting neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Asratyan, A. E.; Davidenko, G. V.; Dolgolenko, A. G.; Kaftanov, V. S.; Kubantsev, M. A.; Verebryusov, V. S.

    2000-08-01

    A conceptual scheme of a hybrid-emulsion spectrometer for investigating various channels of neutrino oscillations is proposed. The design emphasizes detection of τ leptons by detached vertices, reliable identification of electrons, and good spectrometry for all charged particles and photons. A distributed target is formed by layers of low- Z material, emulsion-plastic-emulsion sheets, and air gaps in which τ decays are detected. The tracks of charged secondaries, including electrons, are momentum-analyzed by curvature in magnetic field using hits in successive thin layers of emulsion. The τ leptons are efficiently detected in all major decay channels, including τ-→ e-νν¯. The performance of a model spectrometer, that contains 3 t of nuclear emulsion and 20 t of passive material, is estimated for different experimental environments. When irradiated by the ν μ beam of a proton accelerator over a medium baseline of ˜1 km/ GeV, the spectrometer will efficiently detect either the ν μ→ν τ or the ν μ→ν e transitions in the mass-difference region of Δm 2˜1 eV2, as suggested by the results of LSND. When exposed to the neutrino beam of a muon storage ring over a long baseline of < L/ Eν>˜10- 20 km/ GeV, the model detector will efficiently probe the entire pattern of neutrino oscillations in the region Δ m2˜10 -2- 10 -3 eV2, as suggested by the data on atmospheric neutrinos.

  9. 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.

  10. Energy determination of the cascade shower by means of a new type of emulsion chamber with diffuser module

    NASA Astrophysics Data System (ADS)

    Hareyama, M.; Fujii, M.; Galkin, V. I.; Goto, Y.; Ichimura, M.; Kamioka, E.; Kobayashi, T.; Kopenkin, V.; Kuramata, S.; Managadze, A. K.; Matsutani, H.; Misnikova, N. P.; Mukhamedshin, R. A.; Nanjo, H.; Nazarov, S. N.; Oshuev, D. S.; Publichenko, P. A.; Rakobolskaya, I. V.; Roganova, T. M.; Sazhina, G. P.; Shabanova, Yu. N.; Semba, H.; Shibata, T.; Sugimoto, H.; Sveshnikova, L. G.; Takahashi, K.; Yashin, I. V.; Yokoi, K.; Zamchalova, E. A.; Zatsepin, G. T.; Zayarnaya, I. S.; Runjob Collaboration (Russia-Nippon Joint Balloon Collaboration)

    2003-10-01

    An account is given of a new type of emulsion chambers which have been in our use since 1997 in our RUNJOB program (RUssia-Nippon JOint Balloon-program). Each chamber is equipped with an additional "diffuser module" placed under the usual set of modules. We have made the experiments using 4 cm thick diffuser modules composed of several photo-sensitive layers (X-ray films and/or nuclear emulsion plates) sandwiched with spacers. The result is as follows. Even in the case where the path length of only 6 radiation lengths is available within the calorimeter module placed above, the visible energy sum is determined with an accuracy better than σ˜0.2 for a group of electromagnetic cascade showers induced by a proton of energy up to several tens of TeV, or by an iron nucleus of energy up to one hundred TeV. If the available path length in the calorimeter module is 9 radiation lengths, we can estimate the energy sum up to ˜100 TeV within an accuracy of σ˜0.2 for a proton-induced cascade shower group. It means that the use of our new-type emulsion chamber can reduce the detector payload dramatically, which is essentially important for the high-energy cosmic-ray observations made on board the vehicles such as balloons, satellites and so on.

  11. Combination of emulsion chamber and air shower array at Mt. Chacaltaya

    SciTech Connect

    Kawasumi, N.; Tsushima, I.; Honda, K.; Hashimoto, K. ); Matano, T. ); Mori, K.; Inoue, N.; Ticona, R. ); Ohsawa, A. ); Tamada, M. ); Martinic, N.; Aliaga, Z.; Reguerin, A.; Aguirre, C. )

    1993-06-15

    Data of 34 familes with the accompanying air showers, observed by the combination of emulsion chamber and air shower array at Mt. Chacaltaya, are presented. Comparison with the simulation calculation concludes that a change is necessary in the characteristics of hadron interactions in [ital E][sub 0][ge]10[sup 15] eV.

  12. 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.

  13. Observation of super high energy big family with large scale Fe emulsion chambers

    NASA Technical Reports Server (NTRS)

    1985-01-01

    In order to get higher efficiencies for detecting hadrons and to make technical improvements in the chamber structure, the Mt. Kambala Emulsion Chamber Collaboration constructed 57 sq. m. of Fe chamber, with thickness 29 c.u.(1c.u.=17.6 mm Fe), using 300 tons of Fe plates and made the first exposure from Sept., 1982 to May, 1984. The photosensitive layers consist of X-ray films of Sakura N type, Fuji No. 100 type and Tianjin III type, some of them contain also emulsion plates of Fuji ET7B type. They are inserted between the Fe plates at 2 c.u., beginning at 5 c.u. from the chamber top. In a number of blocks, 3 mm spacings are provided at every 2 c.u. of Fe plates to facilitate the replacement of photosensitive layers, without disassembling the chamber. On the bottom of the chamber Fe plates of thickness 9 mm are placed in order to shield the chamber from the radioactivities of the ground. An event, numbered K2 58 of visible energy sigma E sub gamma = 7345 TeV was found in this exposure. No obvious halo is seen in the event and all the showers are clearly separated and easy to measure. A brief report of the preliminary results is presented.

  14. 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.

  15. 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.

  16. A halo event created at 200 m above the Chacaltaya emulsion chamber

    NASA Technical Reports Server (NTRS)

    Amato, N. M.; Arata, N.; Maldonado, R. H. C.

    1985-01-01

    The results of analysis on a cosmic-ray induced nuclear event with the total visible energy approx. = 1300 TeV which is characterized by the central (halo) part of a strong energy concentration and the outer part of a large lateral spread are presented. The event (named as P06) was detected in the 18th two-storied emulsion chamber exposed at Chacaltaya by Brasil-Japan Collaboration. As the nuclear emulsion plates were inserted at every layer of the concerned blocks in the upper and the lower chambers together with RR- and N-type X-ray films, it is possible to study the details of the event. Some results on P06 have already been reported 1 based on the general measurement of opacity on N-type X-ray films: (1) the total energy of halo is approx. = 1000 TeV; (2) the shower transition reaches its maximum at approx. 16 cu; and (3) the radius of halo is 6.5 mm (at the level of 10 to the 6th power electrons/sq.cm.). The results in more details will be described.

  17. Results of investigation of muon fluxes of superhigh energy cosmic rays with X-ray emulsion chambers

    NASA Technical Reports Server (NTRS)

    Ivanenko, I. P.; Ivanova, M. A.; Kuzmichev, L. A.; Ilyina, N. P.; Mandritskaya, K. V.; Osipova, E. A.; Rakobolskaya, I. V.; Zatsepin, G. T.

    1985-01-01

    The overall data from the investigation of the cosmic ray muon flux in the range of zenith angles (0-90) deg within the energy range (3.5 to 5.0) TeV is presented. The exposure of large X-ray emulsion chambers underground was 1200 tons. year. The data were processe using the method which was applied in the experiment Pamir and differred from the earlier applied one. The obtained value of a slope power index of the differential energy spectrum of the global muon flux is =3.7 that corresponds to the slope of the pion generation differential spectrum, gamma sub PI = 2.75 + or - .04. The analysis of the muon zenith-angular distribution showed that the contribution of rapid generation muons in the total muon flux agree the best with the value .2% and less with .7% at a 90% reliability level.

  18. Effectiveness of Chamber Music Ensemble Experience

    ERIC Educational Resources Information Center

    Zorn, Jay D.

    1973-01-01

    This investigation was concerned with the effectiveness of chamber music ensemble experience for certain members of a ninth grade band and the evaluation of the effectiveness in terms of performing abilities, cognitive learnings, and attitude changes. (Author)

  19. The analysis of interface emulsion detector for the OPERA experiment in JAPAN Scanning facility

    NASA Astrophysics Data System (ADS)

    Fukuda, T.; Kodama, K.; Komatsu, M.; Miyamoto, S.; Morishima, K.; Nakano, T.; Omura, T.; Sakatani, Y.; Sato, O.

    2010-04-01

    The OPERA experiment, designed to search for neutrino oscillations, started its physics run in July 2008. It is the most recent emulsion-counter hybrid experiment. In this experiment two different types of emulsion detectors are used. One is called Emulsion Cloud Chamber (ECC), and is used as a target. The other is called Changeable Sheet (CS), which is attached to the downstream side of each ECC to identify the ECC in which a tagged neutrino interaction occurred. The CS interfaces rough tracking information obtained in the electronic detectors to the ECC and therefore is a key element of the emulsion-counter hybrid experiment. As a first step, a CS selected by electronic detectors is scanned and analyzed to decide if the ECC is to be developed and analyzed in detail; a few CS are usually to be analyzed to identify an ECC for each tagged event due to the inaccuracy of the electronic detectors. The CS has a large scanning area and therefore Japan and Europe (Gran Sasso) are sharing in the CS analysis load to handle the scanning job. In this paper, the CS analysis method developed for the Japan scanning facility is described in detail. 100 million tracks are read out on each CS by an automatic emulsion read-out system ( S-UTS ), most of them are so-called fake tracks mainly due to low momentum Compton electrons or random noise and a few real tracks from a tagged neutrino interaction have to be picked up among a huge background. A dedicated method to reject this background without losing real tracks has been developed on the basis of analyzing track data obtained by S-UTS and combining these data with a final selection using additional information on multiple Coulomb scattering of candidate tracks obtained by human eye check to eliminate a remaining background. Performance of this method is shown to be sufficient for the OPERA experiment.

  20. Experience with the jet chamber of the JADE-experiment

    SciTech Connect

    Heuer, R.D.

    1984-01-01

    The jet chamber, a pictorial drift chamber used as the central track detector of the JADE experiment at PETRA, is briefly described. The present status of the spatial and dE/dx resolutions and the experience during 4 years of operation is reported. Improvement plans for the readout electronics are described and a short review of the jet chamber designed for the proposed LEP experiment OPAL is given.

  1. OUTDOOR SMOG CHAMBER EXPERIMENTS USING AUTOMOBILE EXHAUST

    EPA Science Inventory

    Outdoor smog chamber experiments using automobile exhaust were performed in this study. The purpose of the study was to provide a data base that modelers could use to develop new, improved mechanisms for use in the Empirical Kinetics Modeling Approach (EKMA). Thirty-three dual sm...

  2. PAINT COATINGS: CONTROLLED FIELD AND CHAMBER EXPERIMENTS

    EPA Science Inventory

    To determine the impact of pollution levels on the weathering rates of coatings, laboratory chamber experiments and controlled field exposures at North Carolina and Ohio sites were conducted in such a manner to separate the contributions due to dry deposition, wet deposition, pre...

  3. Remarkable events from X ray emulsion chambers and multiple production at LHC energy

    NASA Astrophysics Data System (ADS)

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

    The CORSIKA programme and specific Monte Carlo collision generators are employed in the interpretation of X-ray emulsion chambers data on super gamma ray families at mountain altitude (Chacaltaya, Kanbala, Pamir...) and in the stratosphere (Concorde, balloons). The consequences of measurement conditions(energy thresholds levels...) are detailed to extract common features for the neutral and charged secondaries. The vertex is approached by invariant mass method, geometry, pseudo rapidity distributions , and factors. Sorting the gamma's coupled in the maximum of invariant histograms, we evaluate the multiplicity , , inelasticity behavior up to LHC energy. Attention is given to the penetration power of EAS which levels off one energy decade around the knee and observations related with the fragmentation region (high energy hadron and gamma spectra in EAS, intensity of families with halo's). Hints of new physics are considered around the intriguing alignments registrated in the energy band between colliders and LHC. Several events (stratosphere and mountain) exhibit coplanar emission at similar visible energy, suggesting the valence diquark breaking. Such violent breaking suppressing the leading cluster recombination might come from the rupture of the string under very high tension between the two partners of the diquark.

  4. Composition and energy spectra of cosmic ray nuclei above 500 GeV/nucleon from the JACEE emulsion chambers

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    The composition and energy spectra of charge groups (C - 0), (Ne - S), and (Z approximately 17) above 500 GeV/nucleon from the experiments of JACEE series balloonborne emulsion chambers are reported. Studies of cosmic ray elemental composition at higher energies provide information on propagation through interstellar space, acceleration mechanisms, and their sources. One of the present interests is the elemental composition at energies above 100 GeV/nucleon. Statistically sufficient data in this energy region can be decisive in judgment of propagation models from the ratios of SECONDARY/PRIMARY and source spectra (acceleration mechanism), as well as speculative contributions of different sources from the ratios of PRIMARY/PRIMARY. At much higher energies, i.e., around 10 to the 15th power eV, data from direct observation will give hints on the knee problem, as to whether they favor an escape effect possibly governed by magnetic rigidity above 10 to the 16th power eV.

  5. Composition and energy spectra of cosmic ray nuclei above 500 GeV/nucleon from the JACEE emulsion chambers

    NASA Astrophysics Data System (ADS)

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

    1985-08-01

    The composition and energy spectra of charge groups (C - 0), (Ne - S), and (Z approximately 17) above 500 GeV/nucleon from the experiments of JACEE series balloonborne emulsion chambers are reported. Studies of cosmic ray elemental composition at higher energies provide information on propagation through interstellar space, acceleration mechanisms, and their sources. One of the present interests is the elemental composition at energies above 100 GeV/nucleon. Statistically sufficient data in this energy region can be decisive in judgment of propagation models from the ratios of SECONDARY/PRIMARY and source spectra (acceleration mechanism), as well as speculative contributions of different sources from the ratios of PRIMARY/PRIMARY. At much higher energies, i.e., around 10 to the 15th power eV, data from direct observation will give hints on the knee problem, as to whether they favor an escape effect possibly governed by magnetic rigidity above 10 to the 16th power eV.

  6. Effect of electron divergence in air gaps on the measurement of the energy of cascades in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Apanasenko, A. V.; Baradzey, L. T.; Kanevskaya, Y. A.; Smorodin, Y. A.

    1975-01-01

    The effect of an increase in electron density in the vicinity of the cascade axis caused by an avalanche passing through the gap between lead filters of the emulsion chamber was investigated experimentally. Optical densities were measured in three X-ray films spaced at 400, 800 and 1200 micrometer from the filter surface having a thickness of 6 cascade units. The optical densities of blackening spots caused by electron photon cascades of 1 to 2, 2 to 7 and greater than 7 BeV energies were measured. The results prove the presence of a gap between the filter and the nuclear emulsion which results in the underestimation of energy by several tenths of a percent.

  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. OBSERVATIONS OF HIGH-ENERGY COSMIC-RAY ELECTRONS FROM 30 GeV TO 3 TeV WITH EMULSION CHAMBERS

    SciTech Connect

    Kobayashi, T.; Komori, Y.; Yoshida, K.; Yanagisawa, K.; Nishimura, J.; Yamagami, T.; Saito, Y.; Tateyama, N.; Yuda, T.; Wilkes, R. J. E-mail: komori-y@kuhs.ac.jp E-mail: nisimura@icrr.u-tokyo.ac.jp E-mail: yuda@icrr.u-tokyo.ac.jp

    2012-12-01

    We have performed a series of cosmic-ray electron observations using balloon-borne emulsion chambers since 1968. While we previously reported the results from subsets of the exposures, the final results of the total exposures up to 2001 are presented here. Our successive experiments have yielded a total exposure of 8.19 m{sup 2} sr day at altitudes of 4.0-9.4 g cm{sup -2}. The performance of the emulsion chambers was examined by accelerator beam tests and Monte Carlo simulations, and the on-board calibrations were carried out by using the flight data. In this work, we present the cosmic-ray electron spectrum in the energy range from 30 GeV to 3 TeV at the top of the atmosphere, which is well represented by a power-law function with an index of -3.28 {+-} 0.10. The observed data can also be interpreted in terms of diffusive propagation models. The evidence of cosmic-ray electrons up to 3 TeV suggests the existence of cosmic-ray electron sources at distances within {approx}1 kpc and times within {approx}1 Multiplication-Sign 10{sup 5} yr ago.

  9. 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.

  10. Design and Implementation of the Frequency Control in an Ultrasonic Break Water-in-Oil Emulsion Chamber

    NASA Astrophysics Data System (ADS)

    Atehortúa, Carlos Mario Giraldo; Pérez, Nicolás; Andrade, Marco Aurelio Brizzotti; Adamowski, Julio Cezar; Pereira, Luiz Octávio Vieira

    Water-in-oil emulsions present high stability and its separation is commonly accelerated by addition of chemical demulsifiers or using electrostatic techniques. An alternative to reduce the amount of demulsifiers is the use of ultrasonic standing waves. In this work, the design and implementation of an ultrasonic demulsifier system operating in the 1 MHz range is presented. The design includes the ultrasonic resonant chamber, the power electronics to drive the piezoelectric transducers and the control system. The control must track the operating frequency, compensating the changes due to temperature variation. The system was evaluated in a laboratory pipeline showing that the use of ultrasound reduces the final water content in all cases.

  11. Bubble chambers for experiments in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    DiGiovine, B.; Henderson, D.; Holt, R. J.; Raut, R.; Rehm, K. E.; Robinson, A.; Sonnenschein, A.; Rusev, G.; Tonchev, A. P.; Ugalde, C.

    2015-05-01

    A bubble chamber has been developed to be used as an active target system for low energy nuclear astrophysics experiments. Adopting ideas from dark matter detection with superheated liquids, a detector system compatible with γ-ray beams has been developed. This detector alleviates some of the limitations encountered in standard measurements of the minute cross-sections of interest to stellar environments. While the astrophysically relevant nuclear reaction processes at hydrostatic burning temperatures are dominated by radiative captures, in this experimental scheme we measure the time-reversed processes. Such photodisintegrations allow us to compute the radiative capture cross-sections when transitions to excited states of the reaction products are negligible. Due to the transformation of phase space, the photodisintegration cross-sections are up to two orders of magnitude higher. The main advantage of the new target-detector system is a density several orders of magnitude higher than conventional gas targets. Also, the detector is virtually insensitive to the γ-ray beam itself, thus allowing us to detect only the products of the nuclear reaction of interest. The development and the operation as well as the advantages and disadvantages of the bubble chamber are discussed.

  12. 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.

  13. Lateral distribution of high energy hadrons and gamma ray in air shower cores observed with emulsion chambers

    NASA Technical Reports Server (NTRS)

    Matano, T.; Machida, M.; Honda, K.; Hashimoto, K.; Navia, C. E.; Kawasumi, N.; Tsushima, I.; Matinic, N.; Aquirre, C.

    1985-01-01

    A high energy event of a bundle of electrons, gamma rays and hadronic gamma rays in an air shower core were observed. The bundles were detected with an emulsion chamber with thickness of 15 cm lead. This air shower is estimated to be initiated with a proton with energy around 10 to the 17th power to 10 to the 18th power eV at an altitude of around 100 gmc/2. Lateral distributions of the electromagnetic component with energy above 2 TeV and also the hadronic component of energy above 6 TeV of this air shower core were determined. Particles in the bundle are produced with process of the development of the nuclear cascade, the primary energy of each interaction in the cascade which produces these particles is unknown. To know the primary energy dependence of transverse momentum, the average products of energy and distance for various average energies of secondary particles are studied.

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

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

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

  15. Penetrative nature of high energy showers observed in Chacaltaya emulsion chamber

    NASA Technical Reports Server (NTRS)

    Funayama, Y.; Tamada, M.

    1985-01-01

    About 30% of single core showers with E (sup gamma) 10 TeV have stronger penetrating power than that expected from electromagnetic showers (e,gamma). On the other hand, their starting points of cascades in the chamber are found to be as shallow as those of (e,gamma) components. It is suggested that those showers are very collimated bundles of hadron and (e,gamma) component. Otherwise, it is assumed that the collision mean free path of those showers in the chamber is shorter than that of hadron with geometrical value.

  16. Multi-step avalanche chambers for final experiment E605

    NASA Astrophysics Data System (ADS)

    Hubbard, J. R.; Coutrakon, G.; Cribier, M.; Mangeot, Ph.; Martin, H.; Mullié, J.; Palanque, S.; Pelle, J.

    1980-10-01

    Physical processein multi-step avalanche chambers, detector properties, and difficulties in operation are discussed. Advantages of multi-step chambers over classical MWPCs for specific experimental problems encountered in experiment E605 (high-flux environment and Cherenkov imaging) are described. Some details of detector design are presented.

  17. 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.

  18. A new cylindrical drift chamber for the MEG II experiment

    NASA Astrophysics Data System (ADS)

    Baldini, A. M.; Baracchini, E.; Berretta, L.; Bianucci, S.; Cavoto, G.; Chiarello, G.; Chiri, C.; Cei, F.; Corvaglia, A.; Dussoni, S.; Fahrni, D.; Galli, L.; Grancagnolo, F.; Grassi, M.; Hofer, A.; Hildebrandt, M.; Ignatov, F.; Miccoli, A.; Nicolò, D.; Orsini, A.; Panareo, M.; Pepino, A.; Pinto, C.; Piredda, G.; Signorelli, G.; Raffaelli, F.; Recchia, L.; Renga, F.; Ripiccini, E.; Tassielli, G.; Tazzioli, A.; Tenchini, F.; Venturini, M.; Voena, C.; Zullo, A.

    2016-07-01

    A new cylindrical drift chamber is currently under construction for the MEG II experiment. The chamber is meant to track low momentum positrons from μ+ decays to search for μ+ →e+ γ events. The detector is segmented in very small drift cells, placed in stereo configuration and operated in a helium-isobutane gas mixture. The use of thin aluminium wires and light gas mixture set the total radiation length of the chamber to only 1.6 ×10-3X0 per track turn allowing for a momentum resolution of ~120 keV/c.

  19. SMOG CHAMBER EXPERIMENTS TO TEST OXIDANT RELATED CONTROL STRATEGY ISSUES

    EPA Science Inventory

    Outdoor smog chamber experiments were performed to address various issues relating to ozone (O3) production and oxidant control strategies. Temperature effects on single hydrocarbon-NOx systems were studied. Propylene-NOx systems were modeled with particular attention to peroxyni...

  20. Dedicated contamination experiments in the Orion laser target chamber

    NASA Astrophysics Data System (ADS)

    Andrew, J.; Chevalier, J.-M.; Egan, D.; Geille, A.; Jadaud, J.-P.; Quessada, J.-H.; Raffestin, D.; Rubery, M.; Treadwell, P.; Videau, L.

    2015-11-01

    The use of solid targets irradiated in a vacuum target chamber by focussed high energy, high power laser beams to study the properties of matter at high densities, pressures and temperatures are well known. An undesirable side effect of these interactions is the generation of plumes of solid, liquid and gaseous matter which move away from the target and coat or physically damage surfaces within the target chamber. The largest aperture surfaces in these chambers are usually the large, high specification optical components used to produce the extreme conditions being studied [e.g. large aperture off axis parabolas, aspheric lenses, X ray optics and planar debris shields]. In order to study these plumes and the effects that they produce a set of dedicated experiments were performed to evaluate target by product coating distributions and particle velocities by a combined diagnostic instrument that utilised metal witness plates, polymer witness plates, fibre velocimetry and low density foam particle catchers.

  1. 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.

  2. Double Hypernuclei Experiment with Hybrid Emulsion Method at J-PARC

    NASA Astrophysics Data System (ADS)

    Ekawa, Hiroyuki

    Double hypernuclei are important probes to study the system with strangeness S = -2. Several emulsion experiments had been performed to search for them. We are planning a new experiment to search for double hypernuclei at the K1.8 beam line in the Hadron Experimental Facility (J-PARC E07 experiment). Ξ- tracks in the emulsion plates and SSD will be automatically connected by a hybrid method. The estimated Ξ- stopped statistics is 10 times as high as that of the KEK E373 experiment. Discoveries of 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 theemulsion plates by tagging Ξ- stopped events. This will be the first measurement to give information on the Ξ- potential at the nuclear surface region.

  3. The time projection chamber for the ALICE experiment

    NASA Astrophysics Data System (ADS)

    Musa, Luciano; ALICE Collaboration

    2003-03-01

    The Time Projection Chamber is the main tracking detector in the central barrel of the ALICE experiment. The task of large acceptance tracking in a heavy ion experiment is similar to that encountered in the NA49 and STAR experiments at the SPS and RHIC respectively. However, the extreme multiplicities of ion collisions at the LHC set qualitatively and quantitatively new demands making new designs indispensable. In this paper we present an overview of the main components, with special focus on the front-end and readout electronics, and some of the most crucial aspects addressed by the R&D activities that have preceded the design and construction of the ALICE TPC.

  4. Outdoor smog-chamber experiments: reactivity of methanol exhaust

    SciTech Connect

    Jeffries, H.E.; Sexton, K.G.; Holleman, M.S.

    1985-09-01

    The purpose of the report was to provide an experimental smog-chamber database especially designed to test photochemical kinetics mechanisms that would be used to assess the effects of methanol fuel use in automobiles. The mechanisms would be used in urban air-quality control models to investigate the advantages of large-scale use of methanol fuel in automobiles. The smog-chamber experiments were performed during three summer months. They have been added to the existing UNC database for photochemical mechanism validation and testing, bringing the total number of dual experiments in the database to over 400. Three different hydrocarbon mixtures were used: a 13-component mixture representing synthetic automobile exhaust; an 18-component mixture representing synthetic urban ambient hydrocarbons; and a 14-component mixture derived from the synthetic automobile exhaust by the addition of n-butane. Three different synthetic methanol-exhaust mixtures were used: 80% methanol/10% formaldehyde; and 100% methanol.

  5. Extra-large crystal emulsion detectors for future large-scale experiments

    NASA Astrophysics Data System (ADS)

    Ariga, T.; Ariga, A.; Kuwabara, K.; Morishima, K.; Moto, M.; Nishio, A.; Scampoli, P.; Vladymyrov, M.

    2016-03-01

    Photographic emulsion is a particle tracking device which features the best spatial resolution among particle detectors. For certain applications, for example muon radiography, large-scale detectors are required. Therefore, a huge surface has to be analyzed by means of automated optical microscopes. An improvement of the readout speed is then a crucial point to make these applications possible and the availability of a new type of photographic emulsions featuring crystals of larger size is a way to pursue this program. This would allow a lower magnification for the microscopes, a consequent larger field of view resulting in a faster data analysis. In this framework, we developed new kinds of emulsion detectors with a crystal size of 600-1000 nm, namely 3-5 times larger than conventional ones, allowing a 25 times faster data readout. The new photographic emulsions have shown a sufficient sensitivity and a good signal to noise ratio. The proposed development opens the way to future large-scale applications of the technology, e.g. 3D imaging of glacier bedrocks or future neutrino experiments.

  6. 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.

  7. The INAF/IAPS Plasma Chamber for ionospheric simulation experiment

    NASA Astrophysics Data System (ADS)

    Diego, Piero

    2016-04-01

    The plasma chamber is particularly suitable to perform studies for the following applications: - plasma compatibility and functional tests on payloads envisioned to operate in the ionosphere (e.g. sensors onboard satellites, exposed to the external plasma environment); - calibration/testing of plasma diagnostic sensors; - characterization and compatibility tests on components for space applications (e.g. optical elements, harness, satellite paints, photo-voltaic cells, etc.); - experiments on satellite charging in a space plasma environment; - tests on active experiments which use ion, electron or plasma sources (ion thrusters, hollow cathodes, field effect emitters, plasma contactors, etc.); - possible studies relevant to fundamental space plasma physics. The facility consists of a large volume vacuum tank (a cylinder of length 4.5 m and diameter 1.7 m) equipped with a Kaufman type plasma source, operating with Argon gas, capable to generate a plasma beam with parameters (i.e. density and electron temperature) close to the values encountered in the ionosphere at F layer altitudes. The plasma beam (A+ ions and electrons) is accelerated into the chamber at a velocity that reproduces the relative motion between an orbiting satellite and the ionosphere (≈ 8 km/s). This feature, in particular, allows laboratory simulations of the actual compression and depletion phenomena which take place in the ram and wake regions around satellites moving through the ionosphere. The reproduced plasma environment is monitored using Langmuir Probes (LP) and Retarding Potential Analyzers (RPA). These sensors can be automatically moved within the experimental space using a sled mechanism. Such a feature allows the acquisition of the plasma parameters all around the space payload installed into the chamber for testing. The facility is currently in use to test the payloads of CSES satellite (Chinese Seismic Electromagnetic Satellite) devoted to plasma parameters and electric field

  8. Recent Emulsion Technologies

    SciTech Connect

    Ariga, A.

    2011-10-06

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

  9. Emulsion chamber observations of primary cosmic-ray electrons in the energy range 30-1000 GeV

    NASA Technical Reports Server (NTRS)

    Nishimura, J.; Fujii, M.; Taira, T.; Aizu, E.; Hiraiwa, H.; Kobayashi, T.; Niu, K.; Ohta, I.; Golden, R. L.; Koss, T. A.

    1980-01-01

    The results of a series of emulsion exposures, beginning in Japan in 1968 and continued in the U.S. since 1975, which have yielded a total balloon-altitude exposure of 98,700 sq m sr s, are presented. The data are discussed in terms of several models of cosmic-ray propagation. Interpreted in terms of the energy-dependent leaky-box model, the spectrum results suggest a galactic electron residence time of 1.0(+2.0, -0.5) x 10 to the 7th yr, which is consistent with results from Be-10 observations. Finally, the possibility that departures from smooth power law behavior in the spectrum due to individual nearby sources will be observable in the energy range above 1 TeV is discussed.

  10. Advanced photon source experience with vacuum chambers for insertion devices

    SciTech Connect

    Hartog, P.D.; Grimmer, J.; Xu, S.; Trakhtenberg, E.; Wiemerslage, G.

    1997-08-01

    During the last five years, a new approach to the design and fabrication of extruded aluminum vacuum chambers for insertion devices was developed at the Advanced Photon Source (APS). With this approach, three different versions of the vacuum chamber, with vertical apertures of 12 mm, 8 mm, and 5 mm, were manufactured and tested. Twenty chambers were installed into the APS vacuum system. All have operated with beam, and 16 have been coupled with insertion devices. Two different vacuum chambers with vertical apertures of 16 mm and 11 mm were developed for the BESSY-II storage ring and 3 of 16 mm chambers were manufactured.

  11. Plastic ball and streamer chamber experiments at the Bevalac

    SciTech Connect

    Ritter, H.G.

    1982-07-01

    Single particle inclusive experiments, and experiments that additionally measure a few correlations like the associated multiplicity, have provided the main contribution to our present understanding of high energy heavy ion collisions. The results from those experiments are in overall agreement with calculations of the cascade and hydrodynamical models. In the cascade model the collision of two nuclei is simulated as a cascade of nucleon-nucleon collisions using measured N-N cross sections. The hydrodynamical model, on the other hand, describes the nuclear collision as that of two fluids and makes use of a nuclear equation of state relating thermal and compressional energy densities to pressure. The pressure field dominates the expansion phase and leads to collective flow of the reaction products in a preferred direction. The observation of such effects in inclusive experiments is not well established. Collective effects that manifest themselves in the shape of the event in phase space are expected to be seen best in the new complete event detectors that measure the final state as exclusively as presently possible by measuring most of the charged particles emitted in the reaction. In addition, those detectors are well suited to test macroscopic concepts such as equilibrium and temperature. Global methods like the sphericity or thrust analysis take into account all the correlations measured in the event and are specially designed to determine the shape of an event in phase space and thus to define a reaction plane. Recent data from the Plastic Ball and the streamer chamber experiments, the first complete event detectors in use at the Bevalac, are presented in this report.

  12. 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...

  13. New analysis of nuclear interaction observed by Mt. Kanbara emulsion chamber experiment

    NASA Technical Reports Server (NTRS)

    Nanjo, H.

    1985-01-01

    To date the analysis of the air cascade family has been performed using a full Monte Carlo simulation. It is difficult to draw a definite conclusion about the interaction mechanism by using only this kind of simulation. On the other hand, attempts to reproduce the original gamma ray at the interaction point, for example decascading, have also been made. This method makes it possible to observe the interaction directly and to analyze the data from various angles. All of these methods, however, assume a constant ER in the cascade shower, where E is energy and R is the distance from the center of the cascade shower. It is impossible to reproduce the exact interaction height and energy by these methods. A relative method in separating one cascade shower from others is adopted. This method makes it possible to estimate the interaction height and energy by using information about the lateral spread of the cascade shower.

  14. Fundamental Experiments and Numerical Analyses on Heat Transfer Characteristics of a Vapor Chamber

    NASA Astrophysics Data System (ADS)

    Koito, Yasushi; Imura, Hideaki; Mochizuki, Masataka; Saito, Yuji; Torii, Shuichi

    A vapor chamber is used as a novel heat spreader to cool high-performance MPUs (microprocessor units). The vapor chamber is placed between small heat sources and a large heat sink. This paper describes the effect of heat source size on the heat transfer characteristics of the vapor chamber. First, by the experiments, the effect of heat source size on the temperature distribution of the vapor chamber is investigated, and the validity of the mathematical model of the vapor chamber is confirmed. Secondly, by the numerical analyses, the effect of heat source size on the thermal resistances inside the vapor chamber is discussed. It is found that the heat source size greatly affects the thermal resistance of the evaporator section inside the vapor chamber. Although the thermal resistance is hardly affected by the heat generation rate and the heat flux of the heat source, it increases as the heat source becomes smaller.

  15. Convective melting in a magma chamber: theory and numerical experiment.

    NASA Astrophysics Data System (ADS)

    Simakin, A.

    2012-04-01

    We present results of the numerical modeling of convective melting in a magma chamber in 2D. Model was pointed on the silicic system approximated with Qz-Fsp binary undersaturated with water. Viscosity was calculated as a function of the melt composition, temperature and crystal content and comprises for the pure melt 104.5-105.5 Pas. Lower boundary was taken thermally insulated in majority of the runs. Size of FEM (bilinear elements) grid for velocity is 25x25 cm and for the integration of the density term 8x8 cm. Melting of the chamber roof proceeds with the heat supply due to the chaotic thermo-compositional convection and conductive heat loose into melted substrate. We compare our numerical data with existing semi-analytical models. Theoretical studies of the assimilation rates in the magma chambers usually use theoretical semi-analytical model by Huppert and Sparks (1988) (e.g., Snyder, 2000). We find that this model has strong points: 1) Independence of the melting rate on the sill thickness (Ra>>Rac) 2) Independence of the convective heat transfer on the roof temperature 3) Determination of the exponential thermal boundary layer ahead of the melting front and weak points: 1) Ignoring the possibility of the crystallization without melting regime for narrow sills and dykes. 2)Neglecting of two-phase character of convection. 3)Ignoring of the strong viscosity variation near the melting front. Independence of convective flux from the sill size (at Ra>>Rac) allows reducing of computational domain to the geologically small size (10-15 m). Concept of exponential thermal boundary layer is also rather important. Length scale (L0) of this layer is related to the melting rate and thermal diffusivity coefficient kT as L0=kT/um and at the melting rate 10 m/yr becomes about 2 m. Such small scale implies that convective melting is very effective (small conductive heat loss) and part of the numerical domain filled with roof rocks can be taken small. In the H&S model

  16. Designing an oscillating CO2 concentration experiment for field chambers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Questions have arisen about photosynthetic response to fluctuating carbon dioxide (CO2), which might affect yield in free-air CO2 enrichment (FACE) systems and in open top chambers. A few studies have been conducted based on CO2 controlled to cycles of fixed time-periods and fixed, large amplitude....

  17. Studies of particle interactions in bubble chamber, spark chambers and counter experiments. Annual progress report

    SciTech Connect

    Holloway, L.E.; O'Halloran, T.A. Jr.; Simmons, R.O.

    1983-07-01

    During the past six years we have carried out and planned experiments which predominantly studied the production and decay of particles containing charmed quarks. A series of photoproduction and neutron production experiments started with the very early observation of the production of J/psi by neutrons and by photons at Fermilab. From subsequent experiments using these neutral beams and the basic detecting system, we have reported results on the photoproduction of the ..lambda../sub c/ charmed baryon and the D and D* charmed mesons. More recent runs are studying the high energy photoproduction of vector mesons including the psi'. The present experiment in this sequence is using neutrons to produce a large number of D mesons. Another series of experiments at Fermilab set out to study the hadronic production of charmed mesons. The Chicago Cyclotron facility was modified with a detector sensitive to various possible production mechanisms. The experiments were a success; clean signals of D mesons were observed to be produced by pions, and also the production of chi/sub c/ with the subsequent decay via a ..gamma..-ray to psi was observed. The charmonium experiments run this year have better photon resolution for measuring the decays of chi/sub c/ to psi. We are part of a collaboration which is working on the Collider Detector Facility for Fermilab. The CDF at Fermilab is a possible source of (weak) intermediate vector bosons from the collisions of protons and anti-protons. Our responsibilities in the CDF include both the construction of the muon detector and the designing, planning, and testing of the FASTBUS electronics. The second part of our weak interaction program is the Neutrino Oscillation experiment which is now under construction at Brookhaven.

  18. Development of glass resistive plate chambers for INO experiment

    NASA Astrophysics Data System (ADS)

    Datar, V. M.; Jena, Satyajit; Kalmani, S. D.; Mondal, N. K.; Nagaraj, P.; Reddy, L. V.; Saraf, M.; Satyanarayana, B.; Shinde, R. R.; Verma, P.

    2009-05-01

    The India-based Neutrino Observatory (INO) collaboration is planning to build a massive 50 kton magnetised Iron Calorimeter (ICAL) detector, to study atmospheric neutrinos and to make precision measurements of the parameters related to neutrino oscillations. Glass Resistive Plate Chambers (RPCs) of about 2 m×2 m in size are going to be used as active elements for the ICAL detector. We have fabricated a large number of glass RPC prototypes of 1 m×1 m in size and have studied their performance and long term stability. In the process, we have developed and produced a number of materials and components required for fabrication of RPCs. We have also designed and optimised a number of fabrication and quality control procedures for assembling the gas gaps. In this paper we will review our various activities towards development of glass RPCs for the INO ICAL detector. We will present results of the characterisation studies of the RPCs and discuss our plans to prototype 2 m×2 m sized RPCs.

  19. 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.

  20. 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.

  1. Smog chamber experiments to test oxidant related control strategy issues. Final report 1978-81

    SciTech Connect

    Kamens, R.M.; Jeffries, H.E.; Sexton, K.G.; Gerhardt, A.A.

    1982-03-01

    Outdoor smog chamber experiments were performed to address various issues relating to ozone (O3) production and oxidant control strategies. Temperature effects on single hydrocarbon-NOx systems were studied. Propylene-NOx systems were modeled with particular attention to peroxynitric acid chemistry. Mechanisms were developed to model the O3 reactions with the two major isoprene daughter products, methylvinylketone and methacrolein. Chamber systems with isoprene and O3 were also modeled.

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

    NASA Astrophysics Data System (ADS)

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

    2014-08-01

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

  3. Experience With the Resistive Plate Chamber in the BaBar Experiment

    SciTech Connect

    Bellini, F.; /Rome U. /INFN, Rome

    2006-11-15

    The BABAR detector has operated nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector, for the past two years. The RPCs experience widely different background and luminosity-driven singles rates (0.01-10 Hz/cm{sup 2}) depending on position within the endcap. Some regions have integrated over 0.3 C/cm{sup 2}. RPC efficiency measured with cosmic rays and beam is high and stable. However, a few of the highest rate RPCs have suffered efficiency losses of 5-15%. Although constructed with improved techniques many of the RPCs, which are operated in streamer mode, have shown increased dark currents and noise rates that are correlated with the direction of the gas flow and the integrated current.

  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. MicroBooNE, A Liquid Argon Time Projection Chamber (LArTPC) Neutrino Experiment

    SciTech Connect

    Katori, Teppei

    2011-07-01

    Liquid Argon time projection chamber (LArTPC) is a promising detector technology for future neutrino experiments. MicroBooNE is a upcoming LArTPC neutrino experiment which will be located on-axis of Booster Neutrino Beam (BNB) at Fermilab, USA. The R&D efforts on this detection method and related neutrino interaction measurements are discussed.

  6. Method for treating tar sands emulsion and apparatus therefor

    SciTech Connect

    Bialek, R.F.

    1986-04-15

    A method is described for resolving a hot bitumen emulsion comprised primarily of bitumen, water and chemical diluents. The method consists of: providing separate but communicated emulsion mixing, and emulsion settling chamber, passing the hot bitumen emulsion through a first elongated mixing passage in the mixing chamber wherein a rapidly flowing stream of recycled emulsion is combined with a minor portion of unrecycled bitumen emulsion, to form a combined bitumen emulsion stream, thereafter passing the combined bitumen emulsion stream into an elongated discontinuous mixing passage comprised of vertically arranged and interconnected mixing passages within the emulsion mixer, where in the combined bitumen emulsion stream passes at a slower rate than in the first elongated mixing passage, passing the combined bitumen emulsion stream into an overflow passage communicated with the second elongated mixing passage, introducing a part of the combined emulsion stream from the overflow passage into the emulsion settling chamber, recycling the remainder of the combined emulsion stream from the overflow passage into the first elongated mixing passage, and removing separated flows of bitumen and water from the settling chamber.

  7. Experiment 8: Environmental Conditions in the ASTROCULTURE(trademark) Plant Chamber During the USML-2 Mission

    NASA Technical Reports Server (NTRS)

    Bula, R. J.; Zhou, Weijia; Yetka, R. A.; Draeger, N. A.

    1998-01-01

    Conducting plant research to assess the impact of microgravity on plant growth and development requires a plant chamber that has the capability to control other environmental parameters involved in plant growth and development. The environmental control in a space-based plant chamber must be equivalent to that available in such facilities used for terrestrial plant research. Additionally, plants are very sensitive to a number of atmospheric gaseous materials. Thus, the atmosphere of a plant chamber must be isolated from the space vehicle atmosphere, and the plant growth unit should have the capability to remove any such deleterious materials that may impact plant growth and development. The Wisconsin Center for Space Automation and Robotics (WCSAR), University of Wisconsin-Madison, has developed a totally enclosed controlled environment plant growth unit. The flight unit was used to support the ASTROCULTURE(TM) experiment conducted during the USML-2 mission. The experiment had two major objectives: 1) Provide further validation of the flight unit to control the experiment-defined environmental parameters in the plant chamber, and 2) support a plant experiment to assess the capability of potato plant material to produce tubers in microgravity. This paper describes the temperature, humidity, and carbon dioxide conditions of the plant chamber during the mission, from launch to landing. Another paper will present the plant response data.

  8. Outdoor smog chamber experiments to test photochemical models. Final report May 78-May 81

    SciTech Connect

    Feffries, H.E.; Kamens, R.M.; Sexron, K.G.; Gerhardt, A.A.

    1982-04-01

    The smog chamber facility of the University of North Carolina was used in a study to provide experimental data for developing and testing kinetic mechanisms of photochemical smog formation. The smog chamber, located outdoors in rural North Carolina, is an A-frame structure covered with Teflon film. Because the chamber is partitioned into two sections, each with a volume of 156 cu m, two experiments can be conducted simultaneously. The dual chamber is operated under natural conditions of solar radiation, temperature, and relative humidity. In this study, 115 dual all-day experiments were conducted using NOx and a variety of organic species. The organic compounds investigated included various paraffins, olefins, aromatics and oxygenates, both singly and in mixtures of two or more components. In this report the data collected over the three-year period of the study are described. The experimental procedures and analytical methods used in this study and the limitations and uncertainties of the data are discussed. Guidance for modeling of the data is also given, including a detailed discussion of how to estimate photolytic rate constants from the available UV and total solar radiation data and how to treat such chamber artifacts as dilution, wall sources and losses of pollutants, and reactivity of the background air.

  9. A facility for long-term Mars simulation experiments: the Mars Environmental Simulation Chamber (MESCH).

    PubMed

    Jensen, Lars Liengaard; Merrison, Jonathan; Hansen, Aviaja Anna; Mikkelsen, Karina Aarup; Kristoffersen, Tommy; Nørnberg, Per; Lomstein, Bente Aagaard; Finster, Kai

    2008-06-01

    We describe the design, construction, and pilot operation of a Mars simulation facility comprised of a cryogenic environmental chamber, an atmospheric gas analyzer, and a xenon/mercury discharge source for UV generation. The Mars Environmental Simulation Chamber (MESCH) consists of a double-walled cylindrical chamber. The double wall provides a cooling mantle through which liquid N(2) can be circulated. A load-lock system that consists of a small pressure-exchange chamber, which can be evacuated, allows for the exchange of samples without changing the chamber environment. Fitted within the MESCH is a carousel, which holds up to 10 steel sample tubes. Rotation of the carousel is controlled by an external motor. Each sample in the carousel can be placed at any desired position. Environmental data, such as temperature, pressure, and UV exposure time, are computer logged and used in automated feedback mechanisms, enabling a wide variety of experiments that include time series. Tests of the simulation facility have successfully demonstrated its ability to produce temperature cycles and maintain low temperature (down to -140 degrees C), low atmospheric pressure (5-10 mbar), and a gas composition like that of Mars during long-term experiments. PMID:18593229

  10. Single Particle Laser Mass Spectrometry Applied to Differential Ice Nucleation Experiments at the AIDA Chamber

    SciTech Connect

    Gallavardin, S. J.; Froyd, Karl D.; Lohmann, U.; Moehler, Ottmar; Murphy, Daniel M.; Cziczo, Dan

    2008-08-26

    Experiments conducted at the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) chamber located in Karlsruhe, Germany permit investigation of particle properties that affect the nucleation of ice at temperature and water vapor conditions relevant to cloud microphysics and climate issues. Ice clouds were generated by heterogeneous nucleation of Arizona test dust (ATD), illite, and hematite and homogeneous nucleation of sulfuric acid. Ice crystals formed in the chamber were inertially separated from unactivated, or ‘interstitial’ aerosol particles with a pumped counterflow virtual impactor (PCVI), then evaporated. The ice residue (i.e., the aerosol which initiated ice nucleation plus any material which was scavenged from the gas- and/or particle-phase), was chemically characterized at the single particle level using a laser ionization mass spectrometer. In this manner the species that first nucleated ice could be identified out of a mixed aerosol population in the chamber. Bare mineral dust particles were more effective ice nuclei (IN) than similar particles with a coating. Metallic particles from contamination in the chamber initiated ice nucleation before other species but there were few enough that they did not compromise the experiments. Nitrate, sulfate, and organics were often detected on particles and ice residue, evidently from scavenging of trace gas-phase species in the chamber. Hematite was a more effective ice nucleus than illite. Ice residue was frequently larger than unactivated test aerosol due to the formation of aggregates due to scavenging, condensation of contaminant gases, and the predominance of larger aerosol in nucleation.

  11. BRANCH CHAMBER SYSTEM AND TECHNIQUES FOR SIMULTANEOUS POLLUTANT EXPOSURE EXPERIMENTS AND GASEOUS FLUX DETERMINATIONS

    EPA Science Inventory

    We describe an experimental system and techniques for use in simultaneous pollutant exposure experiments and gaseous flux determinations. he system uses flexible Teflon bag-like chambers to enclose entire individual branches of young trees. ive gaseous fluxes (CO2, H2O, SO2, O3, ...

  12. Early steps towards quarks and their interactions using neutrino beams in CERN bubble chamber experiments

    NASA Astrophysics Data System (ADS)

    Perkins, Don H.

    2016-06-01

    Results from neutrino experiments at CERN in the1970's, using bubble chamber detectors filled with heavy liquids, gave early evidence for the existence of quarks and gluons as real dynamical objects. In detail, the measured moments of the non-singlet structure functions provided crucial support for the validity of the present theory of the strong inter-quark interactions, quantum chromodynamics.

  13. Ceramic torodail vacuum chamber and wall conditioning for the ETL-TPE-2 experiment

    SciTech Connect

    Kiyama, H.; Kiyama, S.; Hakoda, K.

    1981-01-01

    TPE-2 is a torodial high /beta/screw pinch experiment with an ellitical cross section. This paper presents the design and the fabrication of the torodial ceramic vacuum chamber, the outline of the vacuum system and of major radius of 40 cm and an elliptical cross section of 28 cm.

  14. Early steps towards quarks and their interactions using neutrino beams in CERN bubble chamber experiments

    NASA Astrophysics Data System (ADS)

    Perkins, Don H.

    2016-05-01

    Results from neutrino experiments at CERN in the1970's, using bubble chamber detectors filled with heavy liquids, gave early evidence for the existence of quarks and gluons as real dynamical objects. In detail, the measured moments of the non-singlet structure functions provided crucial support for the validity of the present theory of the strong inter-quark interactions, quantum chromodynamics.

  15. Specifications for and preliminary design of a plant growth chamber for orbital experimental experiments

    NASA Technical Reports Server (NTRS)

    Sweet, H. C.; Simmonds, R. C.

    1976-01-01

    It was proposed that plant experiments be performed on board the space shuttle. To permit the proper execution of most tests, the craft must contain a plant growth chamber which is adequately designed to control those environmental factors which can induce changes in a plant's physiology and morphology. The various needs of, and environmental factors affecting, plants are identified. The permissilbe design, construction and performance limits for a plant-growth chamber are set, and tentative designs were prepared for units which are compatible with both the botanical requirements and the constraints imposed by the space shuttle.

  16. Performance of Drift Chambers for E906/SeaQuest Drell-Yan Experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Nagai, Kei; E906/SeaQuest Collaboration

    2014-09-01

    Naively, the parton distribution of the anti-u and anti-d quark were considered flavor symmetric. However, previous experiments showed that u and d are asymmetric. The E906/SeaQuest Collaboration at Fermilab is precisely measuring the x dependence of the flavor asymmetry in the nucleon at large x (0 . 1 < x < 0 . 45), where x is Bjorken's scaling variables. This measurement is being performed using targets of proton, deuteron, carbon, iron and tungsten. The Drell-Yan process, q q -->γ* -->l+l- , is suited for this measurement, because the process always involves an antiquark. Thus SeaQuest measures the momenta of Drell-Yan muon pairs with a magnetic spectrometer. SeaQuest began a two-year data taking run in the 120 GeV proton beam in November 2013. There are four drift chambers in the SeaQuest spectrometer for tracking of muons. We have checked the performance of the drift chambers using the data. The single-plane efficiency, position resolution and rate tolerance of the drift chambers have been evaluated. The requirements of one of the drift chambers are > 95 % of efficiency, < 400 μ m of position resolution, and 1 kHz/wire/1 mm of rate tolerance. I will report on the results of the chamber performance investigations.

  17. 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.

  18. Spectra, composition, and interactions of nuclei above 10 TeV using magnet-interferometric chambers

    NASA Technical Reports Server (NTRS)

    Gregory, J. C.; Takahashi, Y.

    1991-01-01

    Although the SCIN-MAGIC experiment has, like all ASTROMAG and most other Attached Payload experiments, been 'deselected' from Space Station, it is expected that ultimately such emulsion chambers will be flown on the Station. Some brief studies are described which were made in support of the design efforts for such a program being conducted at NASA Marshall.

  19. Study of charm production in the forward cone at energy ELab ˜ 75 TeV with a two-storey X-ray emulsion chamber exposed at, mountain altitudes

    NASA Astrophysics Data System (ADS)

    Borisov, A. S.; Chubenko, A. P.; Denisova, V. G.; Galkin, V. I.; Guseva, Z. M.; Kanevskaya, E. A.; Kogan, M. G.; Kulikov, V. N.; Morozov, A. E.; Mukhamedshin, R. A.; Puchkov, V. S.; Nazarov, S. I.; Pyatovsky, S. E.; Shoziyoev, G. P.; Smirnova, M. D.; Vargasov, A. V.

    2015-08-01

    The origin of the cosmic ray hadron excess observed in a deep uniform lead X-ray emulsion chamber (XREC) at depths larger than 70 radiation lengths is analyzed. We present preliminary experimental data on the absorption of cosmic ray hadrons in the two-storey XREC with a large air gap exposed at the Tien Shan mountains. The design of the chamber was especially invented to prove the hypothesis on a substantial increase of the charm particle production cross section with energy at ELab ˜ 75 TeV as the main source of the darkness spot excess observed on X-ray films. Experimental data obtained with both a 2-storey XREC and a deep uniform XREC are compared with simulation results calculated with the FANSY 1.0 model. The comparison reveals a qualitative agreement between experimental and simulated data under the assumption of high values of charm particle production cross section at ELab ˜ 75 TeV in the forward kinematic region at xLab > 0.1.

  20. Performance of the Time Expansion Chamber / Transition Radiation Detector in PHENIX Experiment at RHIC

    NASA Astrophysics Data System (ADS)

    Luiz Silva, Cesar

    2004-10-01

    The Time Expansion Chamber / Transition Radiation Detector (TEC/TRD) in the PHENIX Experiment at RHIC measures ionization losses (dE/dX) and transition radiation from charged particles produced by beam collisions. It is designed to perform tracking and identification for charged particles on very high particle multiplicity environment. The TEC/TRD consists of 24 wire chambers readout on both sides filled with recycled Xe-based gas mixture. This wire chamber configuration, besides providing measurements of ionization losses for charged particles, can absorb X-Ray photons generated by transition radiation from incident particles with γ>1000 crossing fiber radiators placed at the entrance of the chambers. This allows TEC/TRD to distinguish electrons from the huge pion signal produced over a broad momentum range (1GeV/c

  1. Are magma chamber boundaries brittle or ductile? Rheological insights from thermal stressing experiments

    NASA Astrophysics Data System (ADS)

    Browning, John; Meredith, Philip G.; Gudmundsson, Agust; Lavallée, Yan; Drymoni, Kyriaki

    2015-04-01

    Rheological conditions at magma chamber boundaries remain poorly understood. Many field observations of deeply-eroded and well-exposed plutons, for example Slaufrudalur and Geitafell in SE Iceland, exhibit a sharp transition between what may have been a partially or fully molten magma chamber and its surrounding brittle host rock. Some studies have suggested a more gradual change in the rheological properties of chamber boundaries, marked by a ductile halo, which is likely to exert a significant impact on their rheological response. Understanding the state and rheological conditions of magma-rock interface and interaction is essential for constraining chamber-boundary failure conditions leading to dyke propagation, onset of volcanic eruption as well as caldera fault formation. We present results from a series of thermal stressing experiments in which we attempt to recreate the likely conditions at magma-chamber boundaries. Cores of volcanic material (25 mm diameter x 65 mm long) were heated to magmatic temperatures under controlled conditions in a horizontal tube furnace (at atmospheric pressure) and then held at those temperatures over variable dwell times. At the maximum temperatures reached, the inner part of the samples undergoes partial melting whilst the outer part remains solid. After cooling the brittle shells commonly exhibit axial, fissure-like fractures with protruded blobs of solidified melt. This phenomenon is interpreted as being the result of volume expansion during partial melting. The internal melt overpressure generates fluid-driven fractures analogous to filter-pressing textures or on a large scale, dykes. We complement our observations with acoustic emission and seismic velocity data obtained from measurements throughout the experiments. These complementary data are used to infer the style and timescale of fracture formation. Our results pinpoint the temperature ranges over which brittle fractures form as a result of internal melt overpressure

  2. MicroBooNE: A New Liquid Argon Time Projection Chamber Experiment

    SciTech Connect

    Soderberg, M.

    2009-10-01

    Liquid Argon Time Projection Chamber detectors are well suited to study neutrino interactions, and are an intriguing option for future massive detectors capable of measuring the parameters that characterize neutrino oscillations. These detectors combine fine-grained tracking with calorimetry, allowing for excellent imaging and particle identification ability. In this talk the details of the MicroBooNE experiment, a 175 ton LArTPC which will be exposed to Fermilab's Booster Neutrino Beamline starting in 2011, will be presented. The ability of MicroBooNE to differentiate electrons from photons gives the experiment unique capabilities in low energy neutrino interaction measurements.

  3. The Drift Chamber for the Experiment to Study the Nature of the Confinement

    SciTech Connect

    Berdnikov, Vladimir V.; Somov, S. V.; Pentchev, Lubomir; Zihlmann, Benedikt

    2015-01-01

    The GlueX experiment was designed to search for hybrid mesons with exotic quantum numbers using a beam of linearly polarized photons incident on a liquid hydrogen target. The spectrum of these states and their mass splitting from normal mesons may yield information on confinement. The description of the GlueX spectrometer and Forward Drift Chambers (FDC) as a part of track reconstruction system is presented in the text. FDC‘s are multiwire chambers with cathode and anode read-out. The system allows reconstructing tracks of charged particles with ~200mkm accuracy with angles from 20° up to 1°. One of the detector features is 1.64% X0 material amount in the active area. The cathode gain calibration procedure is presented. The results of such calibration using cosmic data and beam data are presented as well.

  4. The Drift Chamber for the Experiment to Study the Nature of the Confinement

    DOE PAGESBeta

    Berdnikov, Vladimir V.; Somov, S. V.; Pentchev, Lubomir; Zihlmann, Benedikt

    2015-01-01

    The GlueX experiment was designed to search for hybrid mesons with exotic quantum numbers using a beam of linearly polarized photons incident on a liquid hydrogen target. The spectrum of these states and their mass splitting from normal mesons may yield information on confinement. The description of the GlueX spectrometer and Forward Drift Chambers (FDC) as a part of track reconstruction system is presented in the text. FDC‘s are multiwire chambers with cathode and anode read-out. The system allows reconstructing tracks of charged particles with ~200mkm accuracy with angles from 20° up to 1°. One of the detector features ismore » 1.64% X0 material amount in the active area. The cathode gain calibration procedure is presented. The results of such calibration using cosmic data and beam data are presented as well.« less

  5. A Freon-Filled Bubble Chamber for Neutron Detection in Inertial Confinement Fusion Experiments

    SciTech Connect

    Ghilea, M.C.; Meyerhofer, D.D.; Sangster, T.C.

    2011-03-24

    Neutron imaging is one of the main methods used in inertial confinement fusion experiments to measure the core symmetry of target implosions. Previous studies have shown that bubble chambers have the potential to obtain higher resolution images of the targets for a shorter source-to-target distance than typical scintillator arrays. A bubble chamber for neutron imaging with Freon 115 as the active medium was designed and built for the OMEGA laser system. Bubbles resulting from spontaneous nucleation were recorded. Bubbles resulting from neutron–Freon interactions were observed at neutron yields of 1013 emitted from deuterium–tritium target implosions on OMEGA. The measured column bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The recorded data suggest that neutron bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility.

  6. A Freon-filled bubble chamber for neutron detection in inertial confinement fusion experiments

    SciTech Connect

    Ghilea, M. C.; Meyerhofer, D. D.; Sangster, T. C.

    2011-03-15

    Neutron imaging is one of the main methods used in inertial confinement fusion experiments to measure the core symmetry of target implosions. Previous studies have shown that bubble chambers have the potential to obtain higher resolution images of the targets for a shorter source-to-target distance than typical scintillator arrays. A bubble chamber for neutron imaging with Freon 115 as the active medium was designed and built for the OMEGA laser system. Bubbles resulting from spontaneous nucleation were recorded. Bubbles resulting from neutron-Freon interactions were observed at neutron yields of 10{sup 13} emitted from deuterium-tritium target implosions on OMEGA. The measured column bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The recorded data suggest that neutron bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility.

  7. The Drift Chamber for the Experiment to Study the Nature of the Confinement

    NASA Astrophysics Data System (ADS)

    Berdnikov, V. V.; Somov, S. V.; Pentchev, L.; Zihlmann, B.

    The GlueX experiment was designed to search for hybrid mesons with exotic quantum numbers using a beam of linearly polarized photons incident on a liquid hydrogen target. The spectrum of these states and their mass splitting from normal mesons may yield information on confinement. The description of the GlueX spectrometer and Forward Drift Chambers (FDC) as a part of track reconstruction system is presented in the text. FDC's are multiwire chambers with cathode and anode read-out. The system allows reconstructing tracks of charged particles with ∼200mkm accuracy with angles from 20 ̊up to 1 ̊. One of the detector features is 1.64% X0 material amount in the active area. The cathode gain calibration procedure is presented. The results of such calibration using cosmic data and beam data are presented as well.

  8. A position-sensitive twin ionization chamber for fission fragment and prompt neutron correlation experiments

    NASA Astrophysics Data System (ADS)

    Göök, A.; Geerts, W.; Hambsch, F.-J.; Oberstedt, S.; Vidali, M.; Zeynalov, Sh.

    2016-09-01

    A twin position-sensitive Frisch grid ionization chamber, intended as a fission fragment detector in experiments to study prompt fission neutron correlations with fission fragment properties, is presented. Fission fragment mass and energies are determined by means of the double kinetic energy technique, based on conservation of mass and linear momentum. The position sensitivity is achieved by replacing each anode plate in the standard twin ionization chamber by a wire plane and a strip anode, both readout by means of resistive charge division. This provides information about the fission axis orientation, which is necessary to reconstruct the neutron emission process in the fully accelerated fragment rest-frame. The energy resolution compared to the standard twin ionization chamber is found not to be affected by the modification. The angular resolution of the detector relative to an arbitrarily oriented axis is better than 7° FWHM. Results on prompt fission neutron angular distributions in 235U(n,f) obtained with the detector in combination with an array of neutron scintillation detectors is presented as a proof of principle.

  9. Threshold bubble chamber for measurement of knock-on DT neutron tails from magnetic and inertial confinement experiments

    SciTech Connect

    Fisher, R.K.; Zaveryaev, V.S.; Trusillo, S.V.

    1996-07-01

    We propose a new {open_quotes}threshold{close_quotes} bubble chamber detector for measurement of knock-on neutron tails. These energetic neutrons result from fusion reactions involving energetic fuel ions created by alpha knock-on collisions in tokamak and other magnetic confinement experiments, and by both alpha and neutron knock-on collisions in inertial confinement fusion (ICF) experiments. The energy spectrum of these neutrons will yield information on the alpha population and energy distribution in tokamaks, and on alpha target physics and {rho}R measurements in ICF experiments. The bubble chamber should only detect neutrons with energies above a selectable threshold energy controlled by the bubble chamber pressure. The bubble chamber threshold mechanism, detection efficiency, and proposed applications to the International Thermonuclear Experimental Reactor (ITER) and National Ignition Facility (NIF) experiments will be discussed.

  10. Threshold bubble chamber for measurement of knock-on DT neutron tails from magnetic and inertial confinement experiments

    SciTech Connect

    Fisher, R.K.; Zaveryaev, V.S.; Trusillo, S.V.

    1997-01-01

    We propose a new {open_quotes}threshold{close_quotes} bubble chamber detector for measurement of knock-on neutron tails. These energetic neutrons result from fusion reactions involving energetic fuel ions created by alpha knock-on collisions in tokamak and other magnetic confinement experiments, and by both alpha and neutron knock-on collisions in inertial confinement fusion (ICF) experiments. The energy spectrum of these neutrons will yield information on the alpha population and energy distribution in tokamaks, and on alpha target physics and {rho}R measurements in ICF experiments. The bubble chamber should only detect neutrons with energies above a selectable threshold energy controlled by the bubble chamber pressure. The bubble chamber threshold mechanism, detection efficiency, and proposed applications to the International Thermonuclear Experimental Reactor and National Ignition Facility experiments will be discussed. {copyright} {ital 1997 American Institute of Physics.}

  11. Numerical studies on electrostatic field configuration of Resistive Plate Chambers for the INO-ICAL experiment

    NASA Astrophysics Data System (ADS)

    Jash, A.; Majumdar, N.; Mukhopadhyay, S.; Chattopadhyay, S.

    2015-11-01

    As a part of detailed optimization studies on Resistive Plate Chambers (RPC) to be used in INO-ICAL experiment, the effect of geometrical artifacts like edge, corner, spacers on the device response should be investigated thoroughly. In this context, the electrostatic field within an RPC has been computed following Finite Element Method and Boundary Element Method to study the effect of these artifacts on the field map. The weighting field distribution for the given geometry has also been evaluated which is necessary for simulating the device signal. A unified model to calculate both physical and weighting field within RPC has been proposed and tested for its validity.

  12. Plasma chamber testing of APSA coupons for the SAMPIE flight experiment

    NASA Technical Reports Server (NTRS)

    Hillard, G. B.

    1993-01-01

    Different blanket materials and mounting techniques have been used to build 12 Advanced Photovoltaic Solar Array cell coupons for NASA's Solar Array Module Plasma Interactions Experiment. Ground testing of these coupons in a plasma chamber revealed significant differences among them in plasma current collection; while the Kapton-H coupon exhibited current collection consistent with the exposed interconnects, the other two coupon types tested experienced anomalously large collection currents. This may be due to enhanced plasma sheaths supported by the weakly conducting C and Ge employed in these coupons.

  13. Multiwire proportional chambers in M1 and M3 spectrometers of charmed baryon experiment (E781) at Fermilab

    SciTech Connect

    Kaya, Mithat; /Iowa U.

    1997-08-01

    The status of the multiwire proportional chambers in the FERMILAB E781 experiment and a general description of the readout system are given. This essay will describe the system of multiwire proportional chambers (MWPC) that are part of the Fermilab experiment E781 setup. Multiwire proportional chambers are often used in particle physics experiments because they can determine the position of charged particles very accurately (less than a millimeter). The E781 experiment which is also called SELEX (SEgmented LargE-X) is a spectrometer designed to study the production and decay of charmed baryons. MWPCs are part of the 3-stage charged particle spectrometer (Figure 1). Each spectrometer stage includes a bending magnet and chambers. More information about E781 experiment is given in the Appendix. In the following, some basic concepts of MWPCs will be given briefly. After that the multiwire proportional chambers (M1PWC and M3PWC) that are used in the E781 fixed target experiment will be described. Then a general description of the readout system for both M1PWC and M3PWC setups will follow. Finally the tests done on both sets of chambers will be explained in detail.

  14. Continuous measurements of H2 and CO deposition onto soil: a laboratory soil chamber experiment

    NASA Astrophysics Data System (ADS)

    Ghosh, P.; Eiler, J.; Smith, N. V.; Thrift-Viveros, D. L.

    2004-12-01

    Hydrogen uptake in soil is the largest single component of the global budget of atmospheric H2, and is the most important parameter for predicting changes in atmospheric concentration with future changing sources (anthropogenic and otherwise). The rate of hydrogen uptake rate by soil is highly uncertain [1]. As a component of the global budget, it is simply estimated as the difference among estimates for other recognized sources and sinks, assuming the atmosphere is presently in steady state. Previous field chamber experiments [2] show that H2 deposition velocity varies complexly with soil moisture level, and possibly with soil organic content and temperature. We present here results of controlled soil chamber experiments on 3 different soil blocks (each ~20 x ~20 x ~21 cm) with a controlled range of moisture contents. All three soils are arid to semi arid, fine grained, and have organic contents of 10-15%. A positive air pressure (slightly higher than atmospheric pressure) and constant temperature and relative humidity was maintained inside the 10.7 liter, leak-tight plexiglass chamber, and a stream of synthetic air with known H2 concentration was continuously bled into the chamber through a needle valve and mass flow meter. H2, CO and CO2 concentrations were continuously analyzed in the stream of gas exiting the chamber, using a TA 3000 automated Hg-HgO reduced gas analyzer and a LI-820 CO2 gas analyzer. Our experimental protocol involved waiting until concentrations of analyte gases in the exiting gas stream reached a steady state, and documenting how that steady state varied with various soil properties and the rate at which gases were delivered to the chamber. The rate constants for H2 and CO consumption in the chamber were measured at several soil moisture contents. The calculated deposition velocities of H2 and CO into the soil are positively correlated with steady-state concentrations, with slopes and curvatures that vary with soil type and moisture level

  15. Fish oil-based lipid emulsions prevent and reverse parenteral nutrition-associated liver disease: the Boston experience.

    PubMed

    de Meijer, Vincent E; Gura, Kathleen M; Le, Hau D; Meisel, Jonathan A; Puder, Mark

    2009-01-01

    Parenteral nutrition-associated liver disease (PNALD) is the most prevalent and most severe complication of long-term parenteral nutrition. Its underlying pathophysiology, however, largely remains to be elucidated. The currently approved parenteral lipid emulsions in the United States contain safflower or soybean oils, both rich in omega-6 polyunsaturated fatty acids (PUFAs). Mounting evidence indicates that the omega-6 PUFAs originating from plant oils in these lipid emulsions may play a role in the onset of liver injury. Fish oil-based lipid emulsions, in contrast, are primarily composed of omega-3 PUFAs, thus providing a promising alternative. The authors review the literature on the role of lipid emulsions in the onset of PNALD and discuss prevention and treatment strategies using a fish oil-based lipid emulsion. They conclude that a fish oil-based emulsion is hepatoprotective in a murine model of PNALD, and it appears to be safe and efficacious for the treatment of this type of liver disease in children. A prospective randomized trial that is currently under way at the authors' institution will objectively determine the place of fish oil monotherapy in the prevention of PNALD. PMID:19571170

  16. Test Experiments on Muon Radiography with Emulsion Track Detectors in Russia

    NASA Astrophysics Data System (ADS)

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

    Lebedev Physical Institute (LPI RAS) and Skobeltsyn Institute of Nuclear Physics MSU (SINP MSU) have started the series of test muon radiography experiments in Russia. These experiments are aimed at determination of the optimal conditions of the setup, elaboration of algorithms for data processing and the study of the method peculiarities. The final goal of the method development is drafting of monitoring systems for natural and technological objects which condition may be a threat for the population, infrastructure or environment.

  17. Development of a multipurpose vacuum chamber for serial optical and diffraction experiments with free electron laser radiation

    SciTech Connect

    Rajkovic, I.; Hallmann, J.; Gruebel, S.; More, R.; Quevedo, W.; Petri, M.; Techert, S.

    2010-04-15

    In this paper we present a development of a multipurpose vacuum chamber which primal function is to be used in pump/probe experiments with free electron laser (FEL) radiation. The chamber is constructed for serial diffraction and serial spectroscopy allowing a fast exchange of samples during the measurement process. For the fast exchange of samples, liquid jet systems are used. Both applications, utilizing soft x-ray FEL pulses as pump and optical laser pulses as probe and vice versa are documented. Experiments with solid samples as well as the liquid jet samples are presented. When working with liquid jets, a system of automatically refilled liquid traps for capturing liquids has been developed in order to ensure stable vacuum conditions. Differential pumping stages are placed in between the FEL beamline and the experimental chamber so that working pressure in the chamber can be up to four orders of magnitude higher than the pressure in the FEL beamline.

  18. Development of a multipurpose vacuum chamber for serial optical and diffraction experiments with free electron laser radiation.

    PubMed

    Rajkovic, I; Hallmann, J; Grübel, S; More, R; Quevedo, W; Petri, M; Techert, S

    2010-04-01

    In this paper we present a development of a multipurpose vacuum chamber which primal function is to be used in pump/probe experiments with free electron laser (FEL) radiation. The chamber is constructed for serial diffraction and serial spectroscopy allowing a fast exchange of samples during the measurement process. For the fast exchange of samples, liquid jet systems are used. Both applications, utilizing soft x-ray FEL pulses as pump and optical laser pulses as probe and vice versa are documented. Experiments with solid samples as well as the liquid jet samples are presented. When working with liquid jets, a system of automatically refilled liquid traps for capturing liquids has been developed in order to ensure stable vacuum conditions. Differential pumping stages are placed in between the FEL beamline and the experimental chamber so that working pressure in the chamber can be up to four orders of magnitude higher than the pressure in the FEL beamline. PMID:20441366

  19. A time projection chamber for high-rate experiments: Towards an upgrade of the ALICE TPC

    NASA Astrophysics Data System (ADS)

    Ketzer, Bernhard

    2013-12-01

    A Time Projection Chamber (TPC) is a powerful detector for three-dimensional tracking and particle identification for ultra-high multiplicity events. It is the central tracking device of many experiments, e.g. of the ALICE experiment at CERN. The necessity of a switching electrostatic gate, which prevents ions produced in the amplification region of the MWPCs from entering the drift volume, however, restricts its application to trigger rates of the order of 1 kHz. Charge amplification by Gas Electron Multiplier (GEM) foils instead of proportional wires offers an intrinsic suppression of the ion backflow, although not to the same level as a gating grid. Detailed Monte Carlo simulations have shown that the distortions due to residual space charge from back-drifting ions can be limited to a few cm, and thus can be corrected using standard calibration techniques. A prototype GEM-TPC has been built with the largest active volume to date for a detector of this type. It has been commissioned with cosmic rays and with particle beams at the FOPI experiment at GSI, and was employed for a physics measurement with pion beams. For the future operation of the ALICE TPC at the CERN LHC beyond 2019, where Pb-Pb collision rates of 50 kHz are expected, it is planned to replace the existing MWPCs by GEM detectors, operated in a continuous, triggerless readout mode, thus allowing an increase in event rate by a factor of 100. As a first step of the R&D program, a prototype of an Inner Readout Chamber was equipped with large-size GEM foils and exposed to beams of protons, pions and electrons from the CERN PS. In this paper, new results are shown concerning ion backflow, spatial and momentum resolution of the FOPI GEM-TPC, detector calibration, and dE/dx resolution with both detector prototypes. The perspectives of a GEM-TPC for ALICE with continuous readout will be discussed.

  20. Two Years of Industrial Experience in the Use of a Small, Direct Field Acoustic Chamber

    NASA Astrophysics Data System (ADS)

    Saggini, Nicola; Di Pietro, Vincenzo; Poulain, Nicolas; Herzog, Philippe

    2012-07-01

    Within Thales Alenia Space - Italy small satellite Assembly Integration and Test (AIT) plant, the need to develop a suitable facility for spacecraft acoustic noise test has arisen, with additional constraints posed by the necessity of a low impact on the existing building layout, low cost of procurement and operations, while maintaining a high reliability of the system for a theoretical maximum throughput of one test per week over an extended period of time, e.g. six months. The needs have been answered by developing a small (~40 m3 test volume), direct field (DF A T) acoustic test chamber, christened “Alpha Cabin”, where noise generation is achieved by means of commercial audio drivers equipped with custom enclosures. The paper starts with a brief presentation of the main characteristics of the system, but then concentrates on the lessons learnt and return of experience from the tests conducted in more than two years of continuous use. Starting from test article structural responses and their comparison with reverberant chambers, properties of the acoustic field and their implications on the former are analyzed.

  1. Small-strip Thin Gap Chambers for the muon spectrometer upgrade of the ATLAS experiment

    NASA Astrophysics Data System (ADS)

    Perez Codina, E.

    2016-07-01

    The ATLAS muon system upgrade to be installed during the LHC long shutdown in 2018/19, the so-called New Small Wheel (NSW), is designed to cope with the increased instantaneous luminosity in LHC Run 3. The small-strip Thin Gap Chambers (sTGC) will provide the NSW with a fast trigger and high precision tracking. The construction protocol has been validated by test beam experiments on a full-size prototype sTGC detector, showing the performance requirements are met. The intrinsic spatial resolution for a single layer has been found to be about 45 μm for a perpendicular incident angle, and the transition region between pads has been measured to be about 4 mm.

  2. Web-based monitoring tools for Resistive Plate Chambers in the CMS experiment at CERN

    NASA Astrophysics Data System (ADS)

    Kim, M. S.; Ban, Y.; Cai, J.; Li, Q.; Liu, S.; Qian, S.; Wang, D.; Xu, Z.; Zhang, F.; Choi, Y.; Kim, D.; Goh, J.; Choi, S.; Hong, B.; Kang, J. W.; Kang, M.; Kwon, J. H.; Lee, K. S.; Lee, S. K.; Park, S. K.; Pant, L. M.; Mohanty, A. K.; Chudasama, R.; Singh, J. B.; Bhatnagar, V.; Mehta, A.; Kumar, R.; Cauwenbergh, S.; Costantini, S.; Cimmino, A.; Crucy, S.; Fagot, A.; Garcia, G.; Ocampo, A.; Poyraz, D.; Salva, S.; Thyssen, F.; Tytgat, M.; Zaganidis, N.; Doninck, W. V.; Cabrera, A.; Chaparro, L.; Gomez, J. P.; Gomez, B.; Sanabria, J. C.; Avila, C.; Ahmad, A.; Muhammad, S.; Shoaib, M.; Hoorani, H.; Awan, I.; Ali, I.; Ahmed, W.; Asghar, M. I.; Shahzad, H.; Sayed, A.; Ibrahim, A.; Aly, S.; Assran, Y.; Radi, A.; Elkafrawy, T.; Sharma, A.; Colafranceschi, S.; Abbrescia, M.; Calabria, C.; Colaleo, A.; Iaselli, G.; Loddo, F.; Maggi, M.; Nuzzo, S.; Pugliese, G.; Radogna, R.; Venditti, R.; Verwillingen, P.; Benussi, L.; Bianco, S.; Piccolo, D.; Paolucci, P.; Buontempo, S.; Cavallo, N.; Merola, M.; Fabozzi, F.; Iorio, O. M.; Braghieri, A.; Montagna, P.; Riccardi, C.; Salvini, P.; Vitulo, P.; Vai, I.; Magnani, A.; Dimitrov, A.; Litov, L.; Pavlov, B.; Petkov, P.; Aleksandrov, A.; Genchev, V.; Iaydjiev, P.; Rodozov, M.; Sultanov, G.; Vutova, M.; Stoykova, S.; Hadjiiska, R.; Ibargüen, H. S.; Morales, M. I. P.; Bernardino, S. C.; Bagaturia, I.; Tsamalaidze, Z.; Crotty, I.

    2014-10-01

    The Resistive Plate Chambers (RPC) are used in the CMS experiment at the trigger level and also in the standard offline muon reconstruction. In order to guarantee the quality of the data collected and to monitor online the detector performance, a set of tools has been developed in CMS which is heavily used in the RPC system. The Web-based monitoring (WBM) is a set of java servlets that allows users to check the performance of the hardware during data taking, providing distributions and history plots of all the parameters. The functionalities of the RPC WBM monitoring tools are presented along with studies of the detector performance as a function of growing luminosity and environmental conditions that are tracked over time.

  3. Chamber experiments to investigate the release of fungal IN into the atmosphere

    NASA Astrophysics Data System (ADS)

    Kunert, Anna Theresa; Krüger, Mira; Scheel, Jan Frederik; Helleis, Frank; Pöschl, Ulrich; Fröhlich-Nowoisky, Janine

    2015-04-01

    Biological aerosol particles are ubiquitous in the atmosphere. Several types of microorganisms like bacteria, fungi and lichen have been identified as sources of biological ice nuclei (IN). They are a potentially strong source of atmospheric IN, as some of them are able to catalyze ice formation at relatively warm subfreezing temperatures. Common plant-associated bacteria are the best-known biological IN but recently ice nucleation activity in a variety of fungal species such as Mortierella alpina, Isaria farinosa, Acremonium implicatum was found. These fungal species are widely spread throughout the world and are present in soil and air. Their IN seem to be proteins, which are not anchored in the fungal cell wall. To which extent these small, cell-free IN are emitted directly into the atmosphere remains unexplored just as other processes, which probably indirectly release fungal IN e.g. absorbed onto soil dust particles. To analyze the release of fungal IN into the air, we designed a chamber, whose main principle is based on the emission of particles into a closed gas compartment and the subsequent collection of these particles in water. The concentration of the collected IN in the water is determined by droplet freezing assays. For a proof of principles, fungal washing water containing cell-free IN was atomized by an aerosol generator and the produced gas stream was lead through a water trap filled with pure water. Preliminary results show a successful proof of principles. The chamber design is capable of collecting aerosolic IN produced by an aerosol generator with fungal washing water. In ongoing experiments, alive or dead fungal cultures are placed into the chamber and a gentle, particle free air stream is directed over the fungi surface. This gas stream is also lead through water to collect particles, which might be emitted either actively or passively by the fungi. Further experiments will be e.g. conducted under different relative humidities. Results

  4. A review of chamber experiments for determining specific emission rates and investigating migration pathways of flame retardants

    NASA Astrophysics Data System (ADS)

    Rauert, Cassandra; Lazarov, Borislav; Harrad, Stuart; Covaci, Adrian; Stranger, Marianne

    2014-01-01

    The widespread use of flame retardants (FRs) in indoor products has led to their ubiquitous distribution within indoor microenvironments with many studies reporting concentrations in indoor air and dust. Little information is available however on emission of these compounds to air, particularly the measurement of specific emission rates (SERs), or the migration pathways leading to dust contamination. Such knowledge gaps hamper efforts to develop understanding of human exposure. This review summarizes published data on SERs of the following FRs released from treated products: polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), tetrabromobisphenol-A (TBBPA), novel brominated flame retardants (NBFRs) and organophosphate flame retardants (PFRs), including a brief discussion of the methods used to derive these SERs. Also reviewed are published studies that utilize emission chambers for investigations/measurements of mass transfer of FRs to dust, discussing the chamber configurations and methods used for these experiments. A brief review of studies investigating correlations between concentrations detected in indoor air/dust and possible sources in the microenvironment is included along with efforts to model contamination of indoor environments. Critical analysis of the literature reveals that the major limitations with utilizing chambers to derive SERs for FRs arise due to the physicochemical properties of FRs. In particular, increased partitioning to chamber surfaces, airborne particles and dust, causes loss through “sink” effects and results in long times to reach steady state conditions inside the chamber. The limitations of chamber experiments are discussed as well as their potential for filling gaps in knowledge in this area.

  5. Assessment of SAPRC07 with updated isoprene chemistry against outdoor chamber experiments

    NASA Astrophysics Data System (ADS)

    Chen, Yuzhi; Sexton, Kenneth G.; Jerry, Roger E.; Surratt, Jason D.; Vizuete, William

    2015-03-01

    Isoprene, the most emitted non-methane hydrocarbon, is known to influence ozone (O3) formation in urban areas rich with biogenic emissions. To keep up with the recent advance on isoprene oxidation chemistry including the identification of isoprene epoxydiols (IEPOX) as a precursor to secondary organic aerosol (SOA), Xie et al. (2013) updated the SAPRC (Statewide Air Pollution Research Center)-07 chemical mechanism. It is currently unknown how the Xie modification of SAPRC07 impacts the ability of the model to predict O3. In this study we will evaluate the Xie mechanism with simulations of 24 isoprene experiments from the UNC Dual Gas-phase Chamber. Our results suggest that the new mechanism increases NOx (nitrogen oxides) inter-conversion and produces more O3 than SAPRC07 for all experiments. In lower-NOx experiments, the new mechanism worsens O3 performance in the wrong direction, increasing bias from 4.92% to 9.44%. We found increased NOx recycling from PANs accounts for that. This could be explained by more PANs made due to increased first generation volatile organic compound (VOC) products and hydroxyl radical (OH) production.

  6. Study of isospin correlation in high energy S + Pb and Pb + Pb interactions with a magnetic-interferometric-emulsion-chamber. Final report

    SciTech Connect

    Takahashi, Yoshiyuki

    1997-12-12

    This report describes the research results of the study of high energy heavy-ion interactions and multi-cluster correlations at the University of Alabama in Huntsville (UAH). This study has been performed as the CERN experiments, EMU05, EMU09 and EMU16, and a part of the RHIC PHENIX and its MVD Collaboration work. Physics objectives and methods are described in chapters 1, 2, 3 and Appendices A1 and A2. The experimental set-up, measurements, an the data analyses at UAH are described in chapters 4 through 10 and Appendices. The UAH research was a quest for high density state of nuclear matter, in terms of finding analysis methods of multi-isospin correlations. The present work emphasized a study of the fluctuation of the particle density, discriminating the isospin for exploring the Disoriented Chiral Condensate (DCC). The analysis methods developed are: (1) Chi-square density test; (2) Run-test; (3) G-test; (4) Fourier analysis; and (5) Lomb`s Periodogram. The application of these methods for central collision events in 2,000 GeV/n S + Pb and 167 GeV/n Pb + Pb produced interesting DCC correlations for a few events. However, further investigation of fluctuations with Monte Carlo method guided them to understand various hidden degree of freedoms in such analyses. The results of the analysis of the experimental data in comparison with the Monte Carlo data did not support the DCC process as compelling. The developed methods evolved for a plan to investigate the DCC in the PHENIX. The study has obtained several mathematical analysis methods from the CERN EMU05/16 experiments for a possible use in RHIC experiments.

  7. The central drift chamber for the D0 experiment: Design, construction and test

    SciTech Connect

    Behnke, T.

    1989-08-01

    A cylindrical drift chamber has been designed and built at the State University of New York at Stony Brook. This chamber is to be installed in the D0 detector which is being completed at the Fermi National Accelerator. In this dissertation the design, construction and testing of this chamber are described. The characteristic features of this chamber are cells formed by solid walls and a modular structure. Much discussion is given to the performance of and results from a chamber made from three final modules which was installed in the D0 interaction region during the 1988/1989 collider run. Using this chamber proton anti-proton interactions were measured at the D0 interaction point.

  8. Radon detection in conical diffusion chambers: Monte Carlo calculations and experiment

    SciTech Connect

    Rickards, J.; Golzarri, J. I.; Espinosa, G.; Vázquez-López, C.

    2015-07-23

    The operation of radon detection diffusion chambers of truncated conical shape was studied using Monte Carlo calculations. The efficiency was studied for alpha particles generated randomly in the volume of the chamber, and progeny generated randomly on the interior surface, which reach track detectors placed in different positions within the chamber. Incidence angular distributions, incidence energy spectra and path length distributions are calculated. Cases studied include different positions of the detector within the chamber, varying atmospheric pressure, and introducing a cutoff incidence angle and energy.

  9. Feasibility of microwave-produced Bragg reflector: Examined by the chamber experiment

    SciTech Connect

    Kuo, S.P.; Zhang, Y.S.

    1990-10-01

    A set of parallel plasma layers is generated by two intersecting microwave pulses in a chamber containing dry air at a pressure comparable to the upper atmosphere. The dependencies of breakdown conditions on the pressure and pulse length are examined. The results are shown to be consistent with the appearance of tad erosion of microwave pulse caused by air breakdown. A Bragg scattering experiment, using the plasma layers as a Bragg reflector is then performed. Both time domain and frequency domain measurements of wave scattering are conducted. ne experiment results are found to agree very well with the theory. Moreover, the time domain measurement of wave scattering provides an unambiguous way for determining the temporal evolution of electron density during the first IMP period. A Langmuir double probe is also used to determine the decay rate of electron density during a later time interval (I ms to 1.1 ms). The propagation of high power microwave pulses through the air is also studied experimentally. The mechanisms responsible for two different degree of tail erosion have been identified. The optimum amplitude of an 1. 1us pulse for maximum energy transfer through the air has been determined.

  10. The Resistive Plate Chambers of the ATLAS experiment:. performance studies on Calibration Stream

    NASA Astrophysics Data System (ADS)

    Mazzaferro, Luca

    2012-08-01

    ATLAS (A Toroidal LHC ApparatuS) is one of the four experiments installed on the hadron-hadron collider LHC at CERN. It is a general purpose experiment, with a physics program which spans from the search for the Higgs Boson to the search of physics Beyond the Standard Model (BSM). An integrated luminosity of about 5 fb-1 is expected to be reached by the end of 2011. The Resistive Plate Chambers, installed in the barrel region, are used to provide the first muon level trigger, and cover an area of 16000 m2, readout by about 350000 electronic channels. To ensure optimal trigger performance, the RPC operational parameters like cluster size, efficiency and spatial resolution are constantly monitored. In order to achieve the desired precision, the data used for the analysis are extracted directly from the second level of the trigger, hence assuring very high statistics. This dedicated event stream, called Calibration Stream, is sent automatically to the RPC Calibration Center in Naples. Here the analysis is performed using an automatic tool tightly integrated in the ATLAS GRID environment, the Local Calibration Data Splitter (LCDS), which configures and manages all the operations required by the analysis (e.g. software environment initialization, grid jobs configuration and submission, data saving and retrieval, etc). The monitored RPC operational parameters, the performance analysis and the LCDS will be presented.

  11. Design of Plant Gas Exchange Experiments in a Variable Pressure Growth Chamber

    NASA Technical Reports Server (NTRS)

    Corey, Kenneth A.

    1996-01-01

    Sustainable human presence in extreme environments such as lunar and martian bases will require bioregenerative components to human life support systems where plants are used for generation of oxygen, food, and water. Reduced atmospheric pressures will be used to minimize mass and engineering requirements. Few studies have assessed the metabolic and developmental responses of plants to reduced pressure and varied oxygen atmospheres. The first tests of hypobaric pressures on plant gas exchange and biomass production at the Johnson Space Center will be initiated in January 1996 in the Variable Pressure Growth Chamber (VPGC), a large, closed plant growth chamber rated for 10.2 psi. Experiments were designed and protocols detailed for two complete growouts each of lettuce and wheat to generate a general database for human life support requirements and to answer questions about plant growth processes in reduced pressure and varied oxygen environments. The central objective of crop growth studies in the VPGC is to determine the influence of reduced pressure and reduced oxygen on the rates of photosynthesis, dark respiration, evapotranspiration and biomass production of lettuce and wheat. Due to the constraint of one experimental unit, internal controls, called pressure transients, will be used to evaluate rates of CO2 uptake, O2 evolution, and H2O generation. Pressure transients will give interpretive power to the results of repeated growouts at both reduced and ambient pressures. Other experiments involve the generation of response functions to partial pressures of O2 and CO2 and to light intensity. Protocol for determining and calculating rates of gas exchange have been detailed. In order to build these databases and implement the necessary treatment combinations in short time periods, specific requirements for gas injections and removals have been defined. A set of system capability checks will include determination of leakage rates conducted prior to the actual crop

  12. Conditions of deep magma chamber beneath Fuji volcano estimated from high- P experiments

    NASA Astrophysics Data System (ADS)

    Asano, K.; Takahashi, E.; Hamada, M.; Ushioda, M.; Suzuki, T.

    2012-12-01

    Fuji volcano, the largest in volume and eruption rate in Japan, is located at the center of Honshu, where North America, Eurasia and Philippine Sea plates meets. Because of the significance of Fuji volcano both in tectonic settings and potential volcanic hazard (particularly after the M9 earthquake in 2011), precise knowledge on its magma feeding system is essentially important. Composition of magma erupted from Fuji volcano in the last 100ky is predominantly basalt (SiO2=50-52wt%, FeO/MgO=1.5-3.0). Total lack of silica-rich magma (basaltic andesite and andesite) which are always present in other nearby volcanoes (e.g., Hakone, Izu-Oshima, see Fig.1) is an important petrologic feature of Fuji volcano. Purpose of this study is to constrain the depth of magma chamber of Fuji volcano and explain its silica-nonenrichment trend. High pressure melting experiments were carried out using two IHPVs at the Magma Factory, Tokyo Institute of Technology (SMC-5000 and SMC-8600, Tomiya et al., 2010). Basalt scoria Tr-1 which represents the final ejecta of Hoei eruption in AD1707, was adopted as a starting material. At 4kbar, temperature conditions were 1050, 1100 and 1150C, and H2O contents were 1.3, 2.7 and 4.7 wt.%, respectively. At 7kbar, temperature conditions were 1075, 1100 and 1125C, and H2O contents were 1.0, 1.1, 3.6 and 6.3wt.%, respectively. The fO2 was controlled at NNO buffer. At 4kbar, crystallization sequence at 3 wt% H2O is magnetite, plagioclase, clinopyroxene and finally orthopyroxene. At 7 kbar, and ~3 wt% H2O, the three minerals (opx, cpx, pl) appears simultaneously near the liquidus. Compositional trend of melt at 4 kbar and 7 kbar are shown with arrows in Fig.1. Because of the dominant crystallization of silica-rich opx at 7 kbar, composition of melt stays in the range SiO2=50-52wt% as predicted by Fujii (2007). Absence of silica-rich rocks in Fuji volcano may be explained by the tectonic setting of the volcano. Because Fuji volcano locates on the plate

  13. Utilizing ARC EMCS Seedling Cassettes as Highly Versatile Miniature Growth Chambers for Model Organism Experiments

    NASA Technical Reports Server (NTRS)

    Freeman, John L.; Steele, Marianne K.; Sun, Gwo-Shing; Heathcote, David; Reinsch, S.; DeSimone, Julia C.; Myers, Zachary A.

    2014-01-01

    The aim of our ground testing was to demonstrate the capability of safely putting specific model organisms into dehydrated stasis, and to later rehydrate and successfully grow them inside flight proven ARC EMCS seedling cassettes. The ARC EMCS seedling cassettes were originally developed to support seedling growth during space flight. The seeds are attached to a solid substrate, launched dry, and then rehydrated in a small volume of media on orbit to initiate the experiment. We hypothesized that the same seedling cassettes should be capable of acting as culture chambers for a wide range of organisms with minimal or no modification. The ability to safely preserve live organisms in a dehydrated state allows for on orbit experiments to be conducted at the best time for crew operations and more importantly provides a tightly controlled physiologically relevant growth experiment with specific environmental parameters. Thus, we performed a series of ground tests that involved growing the organisms, preparing them for dehydration on gridded Polyether Sulfone (PES) membranes, dry storage at ambient temperatures for varying periods of time, followed by rehydration. Inside the culture cassettes, the PES membranes were mounted above blotters containing dehydrated growth media. These were mounted on stainless steel bases and sealed with plastic covers that have permeable membrane covered ports for gas exchange. The results showed we were able to demonstrate acceptable normal growth of C.elegans (nematodes), E.coli (bacteria), S.cerevisiae (yeast), Polytrichum (moss) spores and protonemata, C.thalictroides (fern), D.discoideum (amoeba), and H.dujardini (tardigrades). All organisms showed acceptable growth and rehydration in both petri dishes and culture cassettes initially, and after various time lengths of dehydration. At the end of on orbit ISS European Modular Cultivation System experiments the cassettes could be frozen at ultra-low temperatures, refrigerated, or chemically

  14. Radon emanation chamber: High sensitivity measurements for the SuperNEMO experiment

    SciTech Connect

    Soulé, B.; Collaboration: SuperNEMO Collaboration; and others

    2013-08-08

    Radon is a well-known source of background in ββ0ν experiments due to the high Q{sub β} value of one of its daughter nucleus, {sup 214}Bi. The SuperNEMO collaboration requires a maximum radon contamination of 0.1 mBq/m{sup 3} inside its next-generation double beta decay detector. To reach such a low activity, a drastic screening process has been set for the selection of the detector's materials. In addition to a good radiopurity, a low emanation rate is required. To test this parameter, a Radon Emanation Setup is running at CENBG. It consists in a large emanation chamber connected to an electrostatic detector. By measuring large samples and having a low background level, this setup reaches a sensitivity of a few μ Bq. m{sup −2}. d{sup −1} and is able to qualify materials used in the construction of the SuperNEMO detector.

  15. Plasma chamber testing of APSA coupons for the SAMPIE flight experiment

    NASA Technical Reports Server (NTRS)

    Hillard, G. Barry

    1993-01-01

    Among the solar cell technologies to be tested in space as part of the Solar Array Module Plasma Interactions Experiment (SAMPIE) will be the Advanced Photovoltaic Solar Array (APSA). Several prototype twelve cell coupons were built for NASA using different blanket materials and mounting techniques. The first conforms to the baseline design for APSA which calls for the cells to be mounted on a carbon loaded Kapton blanket to control charging in GEO. When deployed, this design has a flexible blanket supported around the edges. A second coupon was built with the cells mounted on Kapton-H, which was in turn cemented to a solid aluminum substrate. A final coupon was identical to the latter but used germanium coated Kapton to control atomic oxygen attack in LEO. Ground testing of these coupons in a plasma chamber showed considerable differences in plasma current collection. The Kapton-H coupon demonstrated current collection consistent with exposed interconnects and some degree of cell snapover. The other two coupons experienced anomalously large collection currents. This behavior is believed to a consequence of enhanced plasma sheaths supported by the weakly conducting carbon and germanium used in these coupons. The results reported here are the first experimental evidence that the use of such materials can result in power losses to high voltage space power systems.

  16. The analog Resistive Plate Chamber detector of the ARGO-YBJ experiment

    NASA Astrophysics Data System (ADS)

    Bartoli, B.; Bernardini, P.; Bi, X. J.; Branchini, P.; Budano, A.; Camarri, P.; Cao, Z.; Cardarelli, R.; Catalanotti, S.; Chen, S. Z.; Chen, T. L.; Creti, P.; Cui, S. W.; Dai, B. Z.; D'Amone, A.; Danzengluobu; De Mitri, I.; D'Ettorre Piazzoli, B.; Di Girolamo, T.; Di Sciascio, G.; Feng, C. F.; Feng, Zhaoyang; Feng, Zhenyong; Gou, Q. B.; Guo, Y. Q.; He, H. H.; Hu, Haibing; Hu, Hongbo; Iacovacci, M.; Iuppa, R.; Jia, H. Y.; Labaciren; Li, H. J.; Liguori, G.; Liu, C.; Liu, J.; Liu, M. Y.; Lu, H.; Ma, L. L.; Ma, X. H.; Mancarella, G.; Mari, S. M.; Marsella, G.; Martello, D.; Mastroianni, S.; Montini, P.; Ning, C. C.; Panareo, M.; Perrone, L.; Pistilli, P.; Ruggieri, F.; Salvini, P.; Santonico, R.; Shen, P. R.; Sheng, X. D.; Shi, F.; Surdo, A.; Tan, Y. H.; Vallania, P.; Vernetto, S.; Vigorito, C.; Wang, H.; Wu, C. Y.; Wu, H. R.; Xue, L.; Yang, Q. Y.; Yang, X. C.; Yao, Z. G.; Yuan, A. F.; Zha, M.; Zhang, H. M.; Zhang, L.; Zhang, X. Y.; Zhang, Y.; Zhao, J.; Zhaxiciren; Zhaxisangzhu; Zhou, X. X.; Zhu, F. R.; Zhu, Q. Q.; Zizzi, G.

    2015-07-01

    The ARGO-YBJ experiment has been in stable data taking from November 2007 till February 2013 at the YangBaJing Cosmic Ray Observatory (4300 m a.s.l.). The detector consists of a single layer of Resistive Plate Chambers (RPCs) (6700 m2) operated in streamer mode. The signal pick-up is obtained by means of strips facing one side of the gas volume. The digital readout of the signals, while allows a high space-time resolution in the shower front reconstruction, limits the measurable energy to a few hundred TeV. In order to fully investigate the 1-10 PeV region, an analog readout has been implemented by instrumenting each RPC with two large size electrodes facing the other side of the gas volume. Since December 2009 the RPC charge readout has been in operation on the entire central carpet (∼5800 m2). In this configuration the detector is able to measure the particle density at the core position where it ranges from tens to many thousands of particles per m2. Thus ARGO-YBJ provides a highly detailed image of the charge component at the core of air showers. In this paper we describe the analog readout of RPCs in ARGO-YBJ and discuss both the performance of the system and the physical impact on the EAS measurements.

  17. Plasma chamber testing of APSA coupons for the SAMPIE flight experiment

    SciTech Connect

    Hillard, G.B.

    1993-01-01

    Among the solar cell technologies to be tested in space as part of the Solar Array Module Plasma Interactions Experiment (SAMPIE) will be the Advanced Photovoltaic Solar Array (APSA). Several prototype twelve cell coupons were built for NASA using different blanket materials and mounting techniques. The first conforms to the baseline design for APSA which calls for the cells to be mounted on a carbon loaded Kapton blanket to control charging in GEO. When deployed, this design has a flexible blanket supported around the edges. A second coupon was built with the cells mounted on Kapton-H, which was in turn cemented to a solid aluminum substrate. A final coupon was identical to the latter but used germanium coated Kapton to control atomic oxygen attack in LEO. Ground testing of these coupons in a plasma chamber showed considerable differences in plasma current collection. The Kapton-H coupon demonstrated current collection consistent with exposed interconnects and some degree of cell snapover. The other two coupons experienced anomalously large collection currents. This behavior is believed to be a consequence of enhanced plasma sheaths supported by the weakly conducting carbon and germanium used in these coupons. The results reported here are the first experimental evidence that the use of such materials can result in power losses to high voltage space power systems.

  18. On the feasibility of microwave produced Bragg reflector: Examined by the chamber experiment

    NASA Technical Reports Server (NTRS)

    Kuo, S. P.; Zhang, Y. S.; Kossey, Paul A.; Barker, Robert J.

    1990-01-01

    A set of parallel plasma layers is generated by two intersecting microwave pulses in a chamber containing dry air at a pressure comparable to the upper atmosphere. The dependencies of breakdown conditions on the pressure and pulse length are examined. The results are shown to be consistent with the appearance of tail erosion of microwave pulse caused by air breakdown. A Bragg scattering experiment using the plasma layers as a Bragg reflector is then performed. Both time domain and frequency domain measurements of wave scattering are conducted. The results are found to agree very well with the theory. Moreover, the time domain measurement of wave scattering provides an unambiguous way for determining the temporal evolution of electron density during the first 100 microsec period. A Langmuir double probe is also used to determine the decay rate of electron density during a later time interval (1 to 1.1 ms). The propagation of high power microwave pulses through the air is also studied experimentally. The mechanism responsible for two different degrees of tail erosion were identified. The optimum amplitude of a 1.1 microsec pulse for maximum energy transfer through the air was determined.

  19. Supervised Self-Organizing Classification of Superresolution ISAR Images: An Anechoic Chamber Experiment

    NASA Astrophysics Data System (ADS)

    Radoi, Emanuel; Quinquis, André; Totir, Felix

    2006-12-01

    The problem of the automatic classification of superresolution ISAR images is addressed in the paper. We describe an anechoic chamber experiment involving ten-scale-reduced aircraft models. The radar images of these targets are reconstructed using MUSIC-2D (multiple signal classification) method coupled with two additional processing steps: phase unwrapping and symmetry enhancement. A feature vector is then proposed including Fourier descriptors and moment invariants, which are calculated from the target shape and the scattering center distribution extracted from each reconstructed image. The classification is finally performed by a new self-organizing neural network called SART (supervised ART), which is compared to two standard classifiers, MLP (multilayer perceptron) and fuzzy KNN ([InlineEquation not available: see fulltext.] nearest neighbors). While the classification accuracy is similar, SART is shown to outperform the two other classifiers in terms of training speed and classification speed, especially for large databases. It is also easier to use since it does not require any input parameter related to its structure.

  20. Experiments on melt ascent by thermo-mechanical erosion in a magma chamber

    NASA Astrophysics Data System (ADS)

    Shibano, Y.; Sumita, I.; Namiki, A.

    2011-12-01

    A intruding hot magma can melt the colder host rock and ascend. Huppert and Sparks (1988) experimentally modeled this process of thermal erosion by using a hot aqueous solution for the magma and wax as the overlying host rock. When the host rock becomes partially molten, crystals with high melting temperature (e.g., olivine) should settle downwards and affect the thermal convection within the magma. However, this mechanical process was not considered in the previous works. Here we model this process of thermo-mechanical erosion and resulting melt ascent, and conduct a series of experiments in which a convecting molten wax(PEG1000) melts the overlying solid wax which contains glass bead particles (i.e., crystals). We use a quasi-two-dimensional cell (8±8±1cm) and set a vertical temperature difference of Δ T = 33oC. When the solid wax melts, the glass beads settle downwards and affect the convection. Here, the primary control parameter is the glass beads size (d). For d > 180 μ m, the particle settling occurs continuously and are not suspended within the liquid layer. However, for d < 180 μ m, we find that the particle settling occurs in a cyclic manner. Here the particles are being suspended within the liquid layer which suppresses the convection and hence the upward heat transfer. As a consequence, melting of the solid layer ceases after a certain time elapses. When the temperature within the liquid layer becomes sufficiently high, cold plumes develop from the roof and melting and particle settling resumes. We classify the results using three velocities; Vs = Stokes velocity, Vm = roof melting velocity and Vc = convection velocity. We find that when Vm ˜ Vs < Vc, the particles are being suspended in the liquid layer and melting occurs in a cyclic manner. On the other hand, when Vm < Vs < Vc, particle settling occurs continuously. For Vm < Vc ˜ Vs, we find that the thermal convection has a negligible effect on particle settling. We may apply the criterion for

  1. Cloud chamber experiments on the origin of ice crystal complexity in cirrus clouds

    NASA Astrophysics Data System (ADS)

    Schnaiter, M.; Järvinen, E.; Vochezer, P.; Abdelmonem, A.; Wagner, R.; Jourdan, O.; Mioche, G.; Shcherbakov, V. N.; Schmitt, C. G.; Tricoli, U.; Ulanowski, Z.; Heymsfield, A. J.

    2015-11-01

    This study reports on the origin of ice crystal complexity and its influence on the angular light scattering properties of cirrus clouds. Cloud simulation experiments were conducted at the AIDA (Aerosol Interactions and Dynamics in the Atmosphere) cloud chamber of the Karlsruhe Institute of Technology (KIT). A new experimental procedure was applied to grow and sublimate ice particles at defined super- and subsaturated ice conditions and for temperatures in the -40 to -60 °C range. The experiments were performed for ice clouds generated via homogeneous and heterogeneous initial nucleation. Ice crystal complexity was deduced from measurements of spatially resolved single particle light scattering patterns by the latest version of the Small Ice Detector (SID-3). It was found that a high ice crystal complexity is dominating the microphysics of the simulated clouds and the degree of this complexity is dependent on the available water vapour during the crystal growth. Indications were found that the crystal complexity is influenced by unfrozen H2SO4/H2O residuals in the case of homogeneous initial ice nucleation. Angular light scattering functions of the simulated ice clouds were measured by the two currently available airborne polar nephelometers; the Polar Nephelometer (PN) probe of LaMP and the Particle Habit Imaging and Polar Scattering (PHIPS-HALO) probe of KIT. The measured scattering functions are featureless and flat in the side- and backward scattering directions resulting in low asymmetry parameters g around 0.78. It was found that these functions have a rather low sensitivity to the crystal complexity for ice clouds that were grown under typical atmospheric conditions. These results have implications for the microphysical properties of cirrus clouds and for the radiative transfer through these clouds.

  2. Cloud chamber experiments on the origin of ice crystal complexity in cirrus clouds

    NASA Astrophysics Data System (ADS)

    Schnaiter, Martin; Järvinen, Emma; Vochezer, Paul; Abdelmonem, Ahmed; Wagner, Robert; Jourdan, Olivier; Mioche, Guillaume; Shcherbakov, Valery N.; Schmitt, Carl G.; Tricoli, Ugo; Ulanowski, Zbigniew; Heymsfield, Andrew J.

    2016-04-01

    This study reports on the origin of small-scale ice crystal complexity and its influence on the angular light scattering properties of cirrus clouds. Cloud simulation experiments were conducted at the AIDA (Aerosol Interactions and Dynamics in the Atmosphere) cloud chamber of the Karlsruhe Institute of Technology (KIT). A new experimental procedure was applied to grow and sublimate ice particles at defined super- and subsaturated ice conditions and for temperatures in the -40 to -60 °C range. The experiments were performed for ice clouds generated via homogeneous and heterogeneous initial nucleation. Small-scale ice crystal complexity was deduced from measurements of spatially resolved single particle light scattering patterns by the latest version of the Small Ice Detector (SID-3). It was found that a high crystal complexity dominates the microphysics of the simulated clouds and the degree of this complexity is dependent on the available water vapor during the crystal growth. Indications were found that the small-scale crystal complexity is influenced by unfrozen H2SO4 / H2O residuals in the case of homogeneous initial ice nucleation. Angular light scattering functions of the simulated ice clouds were measured by the two currently available airborne polar nephelometers: the polar nephelometer (PN) probe of Laboratoire de Métérologie et Physique (LaMP) and the Particle Habit Imaging and Polar Scattering (PHIPS-HALO) probe of KIT. The measured scattering functions are featureless and flat in the side and backward scattering directions. It was found that these functions have a rather low sensitivity to the small-scale crystal complexity for ice clouds that were grown under typical atmospheric conditions. These results have implications for the microphysical properties of cirrus clouds and for the radiative transfer through these clouds.

  3. [The deposition of tritium in form of HTO from atmosphere moisture to Hypogymnia physodes lichens during chamber experiments].

    PubMed

    Golubeva, V N; Golubev, A V; Kosheleva, T A; Kuznetsova, V F; Mavrin, S V

    2008-01-01

    The results of the deposition of tritium oxide (HTO) from atmosphere to Hypogymnia physodes lichens during chamber experiments are presented. For lichens the content of tissue water tritium (TWT) and organically bound tritium (OBT) were measuremed. Were shown that lichens mainly absorb HTO from atmosphere during first 24 hours. The ratio TWT/HTO of chamber and the velocity of TWT to OBT conversion in lichens were determined. Was noted that the TWT to OBT conversion velocity for lichens is ten times greater than that for deposition of HTO by vascular plant leafs. There was supposed that TWT to OCT conversion in lichens is occurred through alga as well as fungus component of lichens. The intensive deposition HTO from chamber atmosphere by lichens and high velocity of HTO to OBT conversion show the availability to use lichens for determination of atmosphere pollution by HTO. PMID:19004335

  4. The L-SCAN Experiment: Mapping the Axial Magma Chamber Beneath the Eastern Lau Spreading Center

    NASA Astrophysics Data System (ADS)

    Allison, C. M.; Dunn, R.; Brooks, K.; Conder, J. A.; Martinez, F.; Conley, M. M.

    2009-12-01

    The L-SCAN (Lau Spreading Center Active-source Investigation) seismic experiment was designed to examine the relationship between melt supply and magmatic, tectonic, and hydrothermal processes along the Eastern Lau Spreading Center (a RIDGE2000 focus site). This 3-D active-source ocean-bottom-seismometer experiment covers a 100-km-long section of the spreading center, which exhibits significant along-strike variability in seafloor morphology, tectonics, crustal magma storage, and hydrothermal venting. Presumably these changes arise from variations in mantle melt supply. During the seismic experiment, we deployed 84 4-component ocean bottom seismometers (OBS), obtained from the OBSIP national instrument pool, over a 40 x 100 sq. km area centered on the ridge at 20°30'S. Sixty-five seismic lines (50-150 km in length) were shot using the R/V M. G. Langseth's 36-element airgun source, generating ~1 million seismic travel time observations. The experiment extends across three ridge segments, separated by two overlapping spreading centers. The southern segment exhibits an ‘inflated’ cross-sectional area and is underlain by an axial-magma-chamber seismic reflector (as detected by a previous MCS seismic study). We present a preliminary analysis of the L-SCAN refraction data collected along this ridge segment. Travel times of P-wave seismic energy were measured and compared for ray paths as a function of distance from the ridge axis, thereby allowing us to map, to first order, the location of the crustal low-velocity zone that extends beneath the AMC reflector. Only P-wave energy that has traveled within ~2-3 km of the ridge axis clearly exhibits the travel time delays indicative of a crustal low-velocity "mush” zone. We have not yet examined the deeper, Moho- and mantle-turning P-wave arrivals. It has been previously observed that high-temperature venting along this ridge segment is restricted to a narrow region at the ridge axis. We suggest a model in which a

  5. Ageing and performance studies of drift chamber prototypes for the MEG II experiment

    NASA Astrophysics Data System (ADS)

    Venturini, Marco; MEG Collaboration

    2015-01-01

    We present the tests aimed at verifying the proper functioning of the tracking systems of MEG II on small prototypes, estimating the achievable resolutions and evaluating the gain loss experienced by the chamber during its operation.

  6. INTERNATIONAL COMPARISON EXPERIMENT ON THE DETERMINATION OF VOCS EMITTED FROM INDOOR MATERIALS USING SMALL TEST CHAMBERS

    EPA Science Inventory

    The paper discusses an interlaboratory comparison of three materials to assess the agreement among laboratories for characterizing volatile organic compounds emitted from indoor materials and products using small test chambers. esults from the 20 participating laboratories showed...

  7. A high performance Front End Electronics for drift chamber readout in MEG experiment upgrade

    NASA Astrophysics Data System (ADS)

    Chiarello, G.; Chiri, C.; Corvaglia, A.; Grancagnolo, F.; Panareo, M.; Pepino, A.; Pinto, C.; Tassielli, G.

    2016-07-01

    Front End (FE) Electronics plays an essential role in Drift Chambers (DC) for time resolution and, therefore, spatial resolution. The use of cluster timing techniques, by measuring the timing of all the individual ionization clusters after the first one, may enable to reach resolutions even below 100 μm in the measurement of the impact parameter. To this purpose, a Front End Electronics with a wide bandwidth and low noise is mandatory in order to acquire and amplify the drift chamber signals.

  8. Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments

    NASA Astrophysics Data System (ADS)

    Bian, Q.; May, A. A.; Kreidenweis, S. M.; Pierce, J. R.

    2015-10-01

    Smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle and vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimations of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one-third of the initial particle-phase organic mass (41 %) was lost during the experiments, and over half of this particle-organic mass loss was from direct particle wall loss (65 % of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (35 % of the loss). We perform a series of sensitivity tests to understand

  9. Investigation of particle and vapor wall-loss effects on controlled wood-smoke smog-chamber experiments

    NASA Astrophysics Data System (ADS)

    Bian, Q.; May, A. A.; Kreidenweis, S. M.; Pierce, J. R.

    2015-06-01

    Smog chambers are extensively used to study processes that drive gas and particle evolution in the atmosphere. A limitation of these experiments is that particles and gas-phase species may be lost to chamber walls on shorter timescales than the timescales of the atmospheric processes being studied in the chamber experiments. These particle and vapor wall losses have been investigated in recent studies of secondary organic aerosol (SOA) formation, but they have not been systematically investigated in experiments of primary emissions from combustion. The semi-volatile nature of combustion emissions (e.g. from wood smoke) may complicate the behavior of particle and vapor wall deposition in the chamber over the course of the experiments due to the competition between gas/particle and gas/wall partitioning. Losses of vapors to the walls may impact particle evaporation in these experiments, and potential precursors for SOA formation from combustion may be lost to the walls, causing underestimates of aerosol yields. Here, we conduct simulations to determine how particle and gas-phase wall losses contributed to the observed evolution of the aerosol during experiments in the third Fire Lab At Missoula Experiment (FLAME III). We use the TwO-Moment Aerosol Sectional (TOMAS) microphysics algorithm coupled with the organic volatility basis set (VBS) and wall-loss formulations to examine the predicted extent of particle and vapor wall losses. We limit the scope of our study to the dark periods in the chamber before photo-oxidation to simplify the aerosol system for this initial study. Our model simulations suggest that over one third of the initial particle-phase organic mass (36%) was lost during the experiments, and roughly half of this particle organic mass loss was from direct particle wall loss (56% of the loss) with the remainder from evaporation of the particles driven by vapor losses to the walls (44% of the loss). We perform a series of sensitivity tests to understand

  10. The FLAME Deluge: organic aerosol emission ratios from combustion chamber experiments

    NASA Astrophysics Data System (ADS)

    Jolleys, Matthew; Coe, Hugh; McFiggans, Gordon; McMeeking, Gavin; Lee, Taehyoung; Sullivan, Amy; Kreidenweis, Sonia; Collett, Jeff

    2014-05-01

    A high level of variability has been identified amongst organic aerosol (OA) emission ratios (ER) from biomass burning (BB) under ambient conditions. However, it is difficult to assess the influences of potential drivers for this variability, given the wide range of conditions associated with wildfire measurements. Chamber experiments performed under controlled conditions provide a means of examining the effects of different fuel types and combustion conditions on OA emissions from biomass fuels. ERs have been characterised for 67 burns during the second Fire Laboratory at Missoula Experiment (FLAME II), involving 19 different species from 6 fuel types widely consumed in BB events in the US each year. Average normalised dOA/dCO ratios show a high degree of variability, both between and within different fuel types and species, typically exceeding variability between separate plumes in ambient measurements. Relationships with source conditions were found to be complex, with little consistent influence from fuel properties and combustion conditions for the entire range of experiments. No strong correlation across all fires was observed between dOA/dCO and modified combustion efficiency (MCE), which is used as an indicator of the proportional contributions of flaming and smouldering combustion phases throughout each burn. However, a negative correlation exists between dOA/dCO and MCE for some coniferous species, most notably Douglas fir, for which there is also an apparent influence from fuel moisture content. Significant contrasts were also identified between combustion emissions from different fuel components of additional coniferous species. Changes in fire efficiency were also shown to dramatically alter emissions for fires with very similar initial conditions. Although the relationship with MCE is variable between species, there is greater consistency with the level of oxygenation in OA. The ratio of the m/z 44 fragment to total OA mass concentration (f44) as

  11. Cooling Properties of the Shuttle Advanced Crew Escape Spacesuit: Results of an Environmental Chamber Experiment

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas; Gillis, David; Bue, Grant; Son, Chan; Norcross, Jason; Kuznetz, Larry; Chapman, Kirt; Chhipwadia, Ketan; McBride, Tim

    2008-01-01

    The shuttle crew wears the Advanced Crew Escape Spacesuit (ACES) to protect themselves from cabin decompression and to support bail out during landing. ACES is cooled by a liquid-cooled garment (LCG) that interfaces to a heat exchanger that dumps heat into the cabin. The ACES outer layer is made of Gore-Tex(Registered TradeMark), permitting water vapor to escape while containing oxygen. The crew can only lose heat via insensible water losses and the LCG. Under nominal landing operations, the average cabin temperature rarely exceeds 75 F, which is adequate for the ACES to function. Problem A rescue shuttle will need to return 11 crew members if the previous mission suffers a thermal protection system failure, preventing it from returning safely to Earth. Initial analysis revealed that 11 crew members in the shuttle will increase cabin temperature at wheel stop above 80 F, which decreases the ACES ability to keep crew members cool. Air flow in the middeck of the shuttle is inhomogeneous and some ACES may experience much higher temperatures that could cause excessive thermal stress to crew members. Methods A ground study was conducted to measure the cooling efficiency of the ACES at 75 F, 85 F, and 95 F at 50% relative humidity. Test subjects representing 5, 50, and 95 percentile body habitus of the astronaut corps performed hand ergometry keeping their metabolic rate at 400, 600, and 800 BTU/hr for one hour. Core temperature was measured by rectal probe and skin, while inside and outside the suit. Environmental chamber wall and cooling unit inlet and outlet temperatures were measured using high-resolution thermistors ( 0.2 C). Conclusions Under these test conditions, the ACES was able to protect the core temperature of all test subjects, however thermal stress due to high insensible losses and skin temperature and skin heat flow may impact crew performance. Further research should be performed to understand the impact on cognitive performance.

  12. Scintillation counter and wire chamber front end modules for high energy physics experiments

    SciTech Connect

    Baldin, Boris; DalMonte, Lou; /Fermilab

    2011-01-01

    This document describes two front-end modules developed for the proposed MIPP upgrade (P-960) experiment at Fermilab. The scintillation counter module was developed for the Plastic Ball detector time and charge measurements. The module has eight LEMO 00 input connectors terminated with 50 ohms and accepts negative photomultiplier signals in the range 0.25...1000 pC with the maximum input voltage of 4.0 V. Each input has a passive splitter with integration and differentiation times of {approx}20 ns. The integrated portion of the signal is digitized at 26.55 MHz by Analog Devices AD9229 12-bit pipelined 4-channel ADC. The differentiated signal is discriminated for time measurement and sent to one of the four TMC304 inputs. The 4-channel TMC304 chip allows high precision time measurement of rising and falling edges with {approx}100 ps resolution and has internal digital pipeline. The ADC data is also pipelined which allows deadtime-less operation with trigger decision times of {approx}4 {micro}s. The wire chamber module was developed for MIPP EMCal detector charge measurements. The 32-channel digitizer accepts differential analog signals from four 8-channel integrating wire amplifiers. The connection between wire amplifier and digitizer is provided via 26-wire twist-n-flat cable. The wire amplifier integrates input wire current and has sensitivity of 275 mV/pC and the noise level of {approx}0.013 pC. The digitizer uses the same 12-bit AD9229 ADC chip as the scintillator counter module. The wire amplifier has a built-in test pulser with a mask register to provide testing of the individual channels. Both modules are implemented as a 6Ux220 mm VME size board with 48-pin power connector. A custom europack (VME) 21-slot crate is developed for housing these front-end modules.

  13. Note: A versatile mass spectrometer chamber for molecular beam and temperature programmed desorption experiments

    NASA Astrophysics Data System (ADS)

    Tonks, James P.; Galloway, Ewan C.; King, Martin O.; Kerherve, Gwilherm; Watts, John F.

    2016-08-01

    A dual purpose mass spectrometer chamber capable of performing molecular beam scattering (MBS) and temperature programmed desorption (TPD) is detailed. Two simple features of this design allow it to perform these techniques. First, the diameter of entrance aperture to the mass spectrometer can be varied to maximize signal for TPD or to maximize angular resolution for MBS. Second, the mass spectrometer chamber can be radially translated so that it can be positioned close to the sample to maximize signal or far from the sample to maximize angular resolution. The performance of this system is described and compares well with systems designed for only one of these techniques.

  14. Micromegas chambers for the experiment ATLAS at the LHC (A Brief Overview)

    NASA Astrophysics Data System (ADS)

    Gongadze, A. L.

    2016-03-01

    The increase in luminosity and energy of the Large hadron collider (LHC) in the next upgrade (Phase-1) in 2018-2019 will lead to a significant increase in radiation load on the ATLAS detector, primarily in the areas close to the interaction point of the LHC proton beams. One of these regions is the Small Wheel of the ATLAS Muon Spectrometer. It is planned to be replaced with the New Small Wheel that will have Micromegas chambers as main coordinate detectors. The paper gives an overview of all existing types of Micromegas detectors with special focus on the Micromegas chambers for the ATLAS detector upgrade.

  15. Note: A versatile mass spectrometer chamber for molecular beam and temperature programmed desorption experiments.

    PubMed

    Tonks, James P; Galloway, Ewan C; King, Martin O; Kerherve, Gwilherm; Watts, John F

    2016-08-01

    A dual purpose mass spectrometer chamber capable of performing molecular beam scattering (MBS) and temperature programmed desorption (TPD) is detailed. Two simple features of this design allow it to perform these techniques. First, the diameter of entrance aperture to the mass spectrometer can be varied to maximize signal for TPD or to maximize angular resolution for MBS. Second, the mass spectrometer chamber can be radially translated so that it can be positioned close to the sample to maximize signal or far from the sample to maximize angular resolution. The performance of this system is described and compares well with systems designed for only one of these techniques. PMID:27587173

  16. Proton decay and solar neutrino experiment with a liquid argon Time Projection Chamber

    SciTech Connect

    Chen, H.H.; Doe, P.J.; Mahler, H.I.

    1983-01-01

    Recent progress in development of the liquid argon Time Projection Chamber is reviewed. Application of this technique to a search for proton decay and /sup 8/B solar neutrinos with directional sensitivity is considered. The steps necessary for a large scale application of this technique deep underground are described.

  17. Experiences with large-area frisch grid chambers in low-level alpha spectrometry

    NASA Astrophysics Data System (ADS)

    Hötzl, H.; Winkler, R.

    1984-06-01

    The properties of parallel-palte gridded ionization chambers with areas of 300 cm 2, developed by us for alpha spectrometry of samples with low specific alpha activity are reported. Several practical hints for optimum operating conditions are presented. The chambers can be operated routinely at atmospheric pressure for several days, without the need for purification of the gas filling (P10). The minimum detectable activity at 5 MeV is 0.01 pCi, based on 4.65 standard deviations of background and 1000 min counting time. At the GSF Research Center ionization chambers of this type are used for the analysis of natural alpha emitters, as well as of transuranium nuclides in environmental samples by: (a) direct alpha spectrometry without any previous treatment of the sample, (b) semi-direct spectrometry after removal of organic matter by low-temperature ashing and (c) spectrometry after chemical separation. Some typical examples of application are given. Furthermore the range of application of the chambers in comparison to semiconductor detectors in the field of low-level alpha spectrometry is discussed.

  18. Flow chamber

    DOEpatents

    Morozov, Victor

    2011-01-18

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  19. A new construction technique of high granularity and high transparency drift chambers for modern high energy physics experiments

    NASA Astrophysics Data System (ADS)

    Chiarello, G.; Chiri, C.; Corvaglia, A.; Grancagnolo, F.; Miccoli, A.; Panareo, M.; Pepino, A.; Pinto, C.; Primiceri, P.; Spedicato, M.; Tassielli, G. F.

    2016-07-01

    Modern experiments for the search of extremely rare processes require high resolutions (order of 50-200 keV/c) tracking systems for particle momenta in the range of 50-300 MeV/c, dominated by multiple scattering contributions. We will present a newly developed construction technique for ultra-low mass Drift Chambers fulfilling this goal. It consists of (1) a semiautomatic wiring machine with a high degree of control over wire mechanical tensioning (better than 0.2 g) and over wire positioning (of the order of 20 μm) for simultaneous wiring of multi-wire layers; (2) a contact-less IR laser soldering tool designed for a feed-through-less wire anchoring system; (3) an automatic handling system for storing and transporting the multi-wire layers to be placed over the drift chamber end-plates. These techniques have been successfully implemented at INFN-Lecce and University of Salento and are currently being used for the construction of Drift Chamber of the MEG (μ → eγ) upgrade experiment.

  20. Methane emission estimates using chamber and tracer release experiments for a municipal waste water treatment plant

    NASA Astrophysics Data System (ADS)

    Yver Kwok, C. E.; Müller, D.; Caldow, C.; Lebègue, B.; Mønster, J. G.; Rella, C. W.; Scheutz, C.; Schmidt, M.; Ramonet, M.; Warneke, T.; Broquet, G.; Ciais, P.

    2015-07-01

    This study presents two methods for estimating methane emissions from a waste water treatment plant (WWTP) along with results from a measurement campaign at a WWTP in Valence, France. These methods, chamber measurements and tracer release, rely on Fourier transform infrared spectroscopy and cavity ring-down spectroscopy instruments. We show that the tracer release method is suitable for quantifying facility- and some process-scale emissions, while the chamber measurements provide insight into individual process emissions. Uncertainties for the two methods are described and discussed. Applying the methods to CH4 emissions of the WWTP, we confirm that the open basins are not a major source of CH4 on the WWTP (about 10 % of the total emissions), but that the pretreatment and sludge treatment are the main emitters. Overall, the waste water treatment plant is representative of an average French WWTP.

  1. IFE Final Optics and Chamber Dynamics Modeling and Experiments Final Technical Report

    SciTech Connect

    F. Najmabadi; M. S. Tillack

    2006-01-11

    Our OFES-sponsored research on IFE technology originally focused on studies of grazing-incidence metal mirrors (GIMM's). After the addition of GIMM research to the High Average Power Laser (HAPL) program, our OFES-sponsored research evolved to include laser propagation studies, surface material evolution in IFE wetted-wall chambers, and magnetic intervention. In 2003, the OFES IFE Technology program was terminated. We continued to expend resources on a no-cost extension in order to complete student research projects in an orderly way and to help us explore new research directions. Those explorations led to funding in the field of extreme ultraviolet lithography, which shares many issues in common with inertial fusion chambers, and the field of radiative properties of laser-produced plasma.

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

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

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

  3. Modeling SOA formation from alkanes and alkenes in chamber experiments: effect of gas/wall partitioning of organic vapors.

    NASA Astrophysics Data System (ADS)

    Stéphanie La, Yuyi; Camredon, Marie; Ziemann, Paul; Ouzebidour, Farida; Valorso, Richard; Madronich, Sasha; Lee-Taylor, Julia; Hodzic, Alma; Aumont, Bernard

    2014-05-01

    Oxidation products of Intermediate Volatility Organic Compounds (IVOC) are expected to be the major precursors of secondary organic aerosols (SOA). Laboratory experiments were conducted this last decade in the Riverside APRC chamber to study IVOC oxidative mechanisms and SOA formation processes for a large set of linear, branched and cyclic aliphatic hydrocarbons (Ziemann, 2011). This dataset are used here to assess the explicit oxidation model GECKO-A (Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere) (Aumont et al., 2005). The simulated SOA yields agree with the general trends observed in the chamber experiments. They are (i) increasing with the increasing carbon number; (ii) decreasing with increasing methyl branch number; and (iii) increasing for cyclic compounds compared to their corresponding linear analogues. However, simulated SOA yields are systematically overestimated regardless of the precursors, suggesting missing processes in the model. In this study, we assess whether gas-to-wall partitioning of organic vapors can explain these model/observation mismatches (Matsunaga and Ziemann, 2010). First results show that GECKO-A outputs better match the observations when wall uptake of organic vapors is taken into account. Effects of gas/wall partitioning on SOA yields and composition will be presented. Preliminary results suggest that wall uptake is a major process influencing SOA production in the Teflon chambers. References Aumont, B., Szopa, S., Madronich, S.: Modelling the evolution of organic carbon during its gas-phase tropospheric oxidation: development of an explicit model based on a self generating approach. Atmos.Chem.Phys., 5, 2497-2517 (2005). P. J. Ziemann: Effects of molecular structure on the chemistry of aerosol formation from the OH-radical-initiated oxidation of alkanes and alkenes, Int. Rev.Phys.Chem., 30:2, 161-195 (2011). Matsunaga, A., Ziemann, P. J.: Gas-wall partitioning of organic compounds in a Teflon film

  4. Observation of Hadronic Charm Production in a High Resolution Streamer Chamber Experiment

    SciTech Connect

    Sandweiss, J.; et al.

    1980-01-01

    Short-lived particles produced in association with muons have been observed in the interactions of 350-GeV/c protons with neon in a high-resolution streamer chamber. The characteristics of these events are consistent with the expected properties of charmed particles if the average lifetime lies between 10/sup -13/ and 2 x 10/sup -12/ sec. With the assumption that the observed events are mainly D/sup + -/ mesons with lieftimes of approximately 10/sup -12/ sec, the production cross section is estimated to lie between 20 and 50 ..mu..b per nucleon.

  5. Determination of longevities, chamber building rates and growth functions for Operculina complanata from long term cultivation experiments

    NASA Astrophysics Data System (ADS)

    Woeger, Julia; Kinoshita, Shunichi; Wolfgang, Eder; Briguglio, Antonino; Hohenegger, Johann

    2016-04-01

    Operculina complanata was collected in 20 and 50 m depth around the Island of Sesoko belonging to Japans southernmost prefecture Okinawa in a series of monthly sampling over a period of 16 months (Apr.2014-July2015). A minimum of 8 specimens (4 among the smallest and 4 among the largest) per sampling were cultured in a long term experiment that was set up to approximate conditions in the field as closely as possible. A set up allowing recognition of individual specimens enabled consistent documentation of chamber formation, which in combination with μ-CT-scanning after the investigation period permitted the assignment of growth steps to specific time periods. These data were used to fit various mathematical models to describe growth (exponential-, logistic-, generalized logistic-, Gompertz-function) and chamber building rate (Michaelis-Menten-, Bertalanffy- function) of Operculina complanata. The mathematically retrieved maximum lifespan and mean chamber building rate found in cultured Operculina complanata were further compared to first results obtained by the simultaneously conducted "natural laboratory approach". Even though these comparisons hint at a somewhat stunted growth and truncated life spans of Operculina complanata in culture, they represent a possibility to assess and improve the quality of further cultivation set ups, opening new prospects to a better understanding of the their theoretical niches.

  6. Methane emission estimates using chamber and tracer release experiments for a municipal waste water treatment plant

    NASA Astrophysics Data System (ADS)

    Yver-Kwok, C. E.; Müller, D.; Caldow, C.; Lebègue, B.; Mønster, J. G.; Rella, C. W.; Scheutz, C.; Schmidt, M.; Ramonet, M.; Warneke, T.; Broquet, G.; Ciais, P.

    2015-03-01

    This study presents two methods for estimating methane emissions from a waste water treatment plant (WWTP) along with results from a measurement campaign at a WWTP in Valence, France. These methods, chamber measurements and tracer release, rely on Fourier Transform Infrared (FTIR) spectroscopy and Cavity Ring Down Spectroscopy (CRDS) instruments. We show that the tracer release method is suitable to quantify facility- and some process-scale emissions, while the chamber measurements, provide insight into individual process emissions. Uncertainties for the two methods are described and discussed. Applying the methods to CH4 emissions of the WWTP, we confirm that the open basins are not a major source of CH4 on the WWTP (about 10% of the total emissions), but that the pretreatment and sludge treatment are the main emitters. Overall, the waste water treatment plant represents a small part (about 1.5%) of the methane emissions of the city of Valence and its surroundings, which is lower than the national inventories.

  7. Cluster counting drift chamber as high precision tracker for ILC experiments

    NASA Astrophysics Data System (ADS)

    Tassielli, G. F.

    2010-05-01

    We present a drift chamber with unprecedented performances proposed for the "4th-Concept" detector at the next International Linear Collider. The helium rich based gas mixture, the aluminum wires and the carbon fiber structure guarantee high transparency and minimal multiple scattering contribution down to 0.4% X0 whereas a full stereo geometry allows for an efficient three-dimensional track reconstruction. We show that, with the use of the cluster timing technique, thanks to a dedicated front end electronics, both spatial resolution and particle identification can be pushed to their theoretical limits. Moreover, because of its very high granularity, its total integration time is contained within one ILC bunch crossing length ( ˜350 ns). An assessment of the physics potentials of this detector has been investigated with a full simulation of some benchmark reactions at ILC. In this scenario a resolution of the order of Δpt/pt2=10-5 GeV-1 c up to momenta as high as 50 GeV/ c has been achieved. Lastly, due to its potentiality, this drift chamber may represent a valid solution for the central tracker of the Super B, in particular for its excellent performance as in particle identification.

  8. Incidence of DCS and oxygen toxicity in chamber attendants: a 28-year experience.

    PubMed

    Witucki, Pete; Duchnick, Jay; Neuman, Tom; Grover, Ian

    2013-01-01

    Decompression sickness (DCS) and central nervous system oxygen toxicity are inherent risks for "inside" attendants (IAs) of hyperbaric chambers. At the Hyperbaric Medicine Center at the University of California San Diego (UCSD), protocols have been developed for decompressing IAs. Protocol 1: For a total bottom time (TBT) of less than 80 minutes at 2.4 atmospheres absolute (atm abs) or shallower, the U.S. Navy (1955) no-decompression tables were utilized. Protocol 2: For a TBT between 80 and 119 minutes IAs breathed oxygen for 15 minutes prior to initiation of ascent. Protocol 3: For a TBT between 120-139 minutes IAs breathed oxygen for 30 minutes prior to ascent. These protocols have been utilized for approximately 28 years and have produced zero cases of DCS and central nervous system oxygen toxicity. These results, based upon more than 24,000 exposures, have an upper limit of risk of DCS and oxygen toxicity of 0.02806 (95% CI) using UCSD IA decompression Protocol 1, 0.00021 for Protocol 2, and 0.00549 for Protocol 3. We conclude that the utilization of this methodology may be useful at other sea-level multiplace chambers. PMID:23957205

  9. 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.

  10. 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.

  11. Bakeout Chamber Within Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.

    1995-01-01

    Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.

  12. European clinical experience with a dual chamber single pass sensing and pacing defibrillation lead.

    PubMed

    Gradaus, Rainer; Gonska, Bernd D; Stellbrink, Christoph; Cron, Thomas; Tebbenjohanns, Jürgen; Blomström-Lundqvist, Carina; Himmrich, Ewald; Salerno, Jorge A; Osswald, Stefan; Gommer, Erik D; Van Veen, Benno K; Böcker, Dirk

    2002-07-01

    Dual chamber ICDs are increasingly implanted nowadays, mainly to improve discrimination between supraventricular and ventricular arrhythmias but also to maintain AV synchrony in patients with bradycardia. The aim of this study was to investigate a new single pass right ventricular defibrillation lead capable of true bipolar sensing and pacing in the right atrium and integrated bipolar sensing and pacing in the right ventricle. The performance of the lead was evaluated in 57 patients (age 61 +/- 12 years; New York Heart Association 1.9 +/- 0.6, left ventricular ejection fraction 0.38 +/- 0.15) at implant, at prehospital discharge, and during a 1-year follow-up. Sensing and pacing behavior of the lead was evaluated in six different body positions. In four patients, no stable position of the atrial electrode could intraoperatively be found. The intraoperative atrial sensing was 2.3 +/- 1.6 mV and the atrial pacing threshold 0.8 +/- 0.5 V at 0.5 ms. At follow-up, the atrial sensing ranged from 1.5 mV to 2.2 mV and the atrial pacing threshold product from 0.8 to 1.7 V/ms. In 11 patients, an intermittent atrial sensing problem and in 24 patients an atrial pacing dysfunction were observed in at least one body position. In 565 episodes, a sensitivity of 100% and a specificity of 96.5% were found for ventricular arrhythmias. In conclusion, this single pass defibrillation lead performed well as a VDD lead and for dual chamber arrhythmia discrimination. However, loss of atrial capture in 45% of patients preclude its use in patients depending on atrial pacing. PMID:12164450

  13. Emulsion formation at the Pore-Scale

    NASA Astrophysics Data System (ADS)

    Armstrong, R. T.; Van Den Bos, P.; Berg, S.

    2012-12-01

    The use of surfactant cocktails to produce ultra-low interfacial tension between water and oil is an enhanced oil recovery method. In phase behavior tests three distinct emulsion phases are observed: (1) oil-in-water emulsion; (2) microemulsion; and (3) water-in-oil emulsion. However, it is unknown how phase behavior manifests at the pore-scale in a porous media system. What is the time scale needed for microemulsion formation? Where in the pore-space do the microemulsions form? And in what order do the different emulsion phases arrange during oil bank formation? To answer these questions micromodel experiments were conducted. These experiments are used to build a conceptual model for phase behavior at the pore-scale.

  14. 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.

  15. Ion Clusters in Nucleation Experiments in the CERN Cloud Chamber: Sulfuric Acid + Ammonia + Dimethyl Amine + Oxidized Organics

    NASA Astrophysics Data System (ADS)

    Worsnop, D. R.; Schobesberger, S.; Bianchi, F.; Ehrhart, S.; Junninen, H.; Kulmala, M. T.

    2012-12-01

    Nucleation from gaseous precursors is an important source of aerosol particles in the atmosphere. The CLOUD experiment at CERN provides exceptionally clean and well-defined experimental conditions for studies of atmospheric nucleation and initial growth, in a 26 m3 stainless-steel chamber. In addition, the influence of cosmic rays on nucleation and nanoparticle growth can be simulated by exposing the chamber to a pion beam produced by the CERN Proton Synchrotron. A key to understanding the mechanism by which nucleation proceeds in the CLOUD chamber is the use of state-of-the-art instrumentation, including the Atmospheric Pressure interface Time-Of-Flight (APi-TOF) mass spectrometer. The APi-TOF is developed by Tofwerk AG, and Aerodyne Research, Inc., and typically obtains resolutions between 4000 and 6000 Th/Th and mass accuracies < 10 ppm. Sampling occurs directly from atmospheric pressure through a critical orifice. Ions are then focused and guided to the time-of-flight mass spectrometer, while passing through differentially pumped chambers. No ionization of the sampled aerosol is performed; only ions charged in the chamber are detected in the current configuration. For all studied chemical systems, the APi-TOF detected ion clusters that could directly be linked to nucleation. The composition of these ion clusters could be determined based on their exact masses and isotopic patterns. Aided by the chamber's cleanliness and the possibility of enhancing ion concentrations by using CERN's pion beam, a remarkably large fraction of the ion spectra could be identified, even for more complex chemical systems studied. For the ammonia-sulfuric acid-water system, for instance, growing clusters containing ammonia (NH3) and sulfuric acid (H2SO4) were observed up to 3300 Th. Adding dimethyl amine and/or pinanediol into the CLOUD chamber, altered the chemical compositions of the observed ion clusters accordingly. Cluster growth then included mixtures of sulfuric acid and

  16. Smog chamber experiments to investigate Henry's law constants of glyoxal using different seed aerosols

    NASA Astrophysics Data System (ADS)

    Jakob, Ronit

    2014-05-01

    Aerosols play an important role in the chemistry and physics of the atmosphere. Hence, they have a direct as well as an indirect impact on the earth's climate. Depending on their formation, one distinguishes between primary and secondary aerosols[1]. Important groups within the secondary aerosols are the secondary organic aerosols (SOAs). In order to improve predictions about these impacts on the earth's climate the existing models need to be optimized, because they still underestimate SOA formation[2]. Glyoxal, the smallest α-dicarbonyl, not only acts as a tracer for SOA formation but also as a direct contributor to SOA. Because glyoxal has such a high vapour pressure, it was common knowledge that it does not take part in gas-particle partitioning and therefore has no impact on direct SOA formation. However, the Henry's law constant for glyoxal is surprisingly high. This has been explained by the hydration of the aldehyde groups, which means that a species with a lower vapour pressure is produced. Therefore the distribution of glyoxal between gas- and particle phase is atmospherically relevant and the direct contribution of glyoxal to SOA can no longer be neglected. A high salt concentration present in chamber seed aerosols leads to an enhanced glyoxal uptake into the particle. This effect is called "salting-in". The salting effect depends on the composition of the seed aerosol as well as the soluble compound. For very polar compounds, like glyoxal, a "salting-in" is observed[3]. Glyoxal particle formation during a smog chamber campaign at Paul-Scherrer-Institut (PSI) in Switzerland was examined using different seed aerosols such as ammonium sulfate, sodium chloride and sodium nitrate. The aim of this campaign was to investigate Henry's law constants for different seed aerosols. During the campaign filter samples were taken to investigate the amount of glyoxal in the particle phase. After filter extraction, the analyte was derivatized and measured using UHPLC

  17. Development of a Novel Contamination Resistant Ion Chamber for Process Tritium Measurement and Use in the JET First Trace Tritium Experiment

    SciTech Connect

    Worth, L.B.C.; Pearce, R.J.H.; Bruce, J.; Banks, J.; Scales, S.

    2005-07-15

    The accuracy of process measurements of tritium with conventional ion chambers is often affected by surface tritium contamination. The measurement of tritium in the exhaust of the JET torus is particularly difficult due to surface contamination with highly tritiated hydrocarbons. JET's first unsuccessful attempt to overcome the contamination problem was to use an ion chamber, with a heating element as the chamber wall so that it could be periodically decontaminated by baking. The newly developed ion chamber works on the principle of minimising the surface area within the boundary of the anode and cathode.This paper details the design of the ion chamber, which utilises a grid of 50-micron tungsten wire to define the ion chamber wall and the collector electrode. The effective surface area which, by contamination, is able to effect the measurement of tritium within the process gas has been reduced by a factor of {approx}200 over a conventional ion chamber. It is concluded that the new process ion chamber enables sensitive accurate tritium measurements free from contamination issues. It will be a powerful new tool for future tritium experiments both to improve tritium tracking and to help in the understanding of tritium retention issues.

  18. Phase transition observations and discrimination of small cloud particles by light polarization in expansion chamber experiments

    NASA Astrophysics Data System (ADS)

    Nichman, Leonid; Fuchs, Claudia; Järvinen, Emma; Ignatius, Karoliina; Florian Höppel, Niko; Dias, Antonio; Heinritzi, Martin; Simon, Mario; Tröstl, Jasmin; Wagner, Andrea Christine; Wagner, Robert; Williamson, Christina; Yan, Chao; Connolly, Paul James; Dorsey, James Robert; Duplissy, Jonathan; Ehrhart, Sebastian; Frege, Carla; Gordon, Hamish; Hoyle, Christopher Robert; Bjerring Kristensen, Thomas; Steiner, Gerhard; McPherson Donahue, Neil; Flagan, Richard; Gallagher, Martin William; Kirkby, Jasper; Möhler, Ottmar; Saathoff, Harald; Schnaiter, Martin; Stratmann, Frank; Tomé, António

    2016-03-01

    Cloud microphysical processes involving the ice phase in tropospheric clouds are among the major uncertainties in cloud formation, weather, and general circulation models. The detection of aerosol particles, liquid droplets, and ice crystals, especially in the small cloud particle-size range below 50 μm, remains challenging in mixed phase, often unstable environments. The Cloud Aerosol Spectrometer with Polarization (CASPOL) is an airborne instrument that has the ability to detect such small cloud particles and measure the variability in polarization state of their backscattered light. Here we operate the versatile Cosmics Leaving OUtdoor Droplets (CLOUD) chamber facility at the European Organization for Nuclear Research (CERN) to produce controlled mixed phase and other clouds by adiabatic expansions in an ultraclean environment, and use the CASPOL to discriminate between different aerosols, water, and ice particles. In this paper, optical property measurements of mixed-phase clouds and viscous secondary organic aerosol (SOA) are presented. We report observations of significant liquid-viscous SOA particle polarization transitions under dry conditions using CASPOL. Cluster analysis techniques were subsequently used to classify different types of particles according to their polarization ratios during phase transition. A classification map is presented for water droplets, organic aerosol (e.g., SOA and oxalic acid), crystalline substances such as ammonium sulfate, and volcanic ash. Finally, we discuss the benefits and limitations of this classification approach for atmospherically relevant concentrations and mixtures with respect to the CLOUD 8-9 campaigns and its potential contribution to tropical troposphere layer analysis.

  19. Investigation, comparison and design of chambers used in centrifugal partition chromatography on the basis of flow pattern and separation experiments.

    PubMed

    Schwienheer, C; Merz, J; Schembecker, G

    2015-04-17

    In centrifugal partition chromatography (CPC) the separation efficiency is mainly influenced by the hydrodynamic of mobile and stationary phase in the chambers. Thus, the hydrodynamic has to be investigated and understood in order to enhance a CPC separation run. Different chamber geometries have been developed in the past and the influence of several phase systems and CPC operating conditions were investigated for these chambers. However, a direct comparison between the different chamber types has not been performed yet. In order to investigate the direct influence of the chamber design on the hydrodynamic, several chamber designs - partially similar in geometry to commercial available designs - are investigated under standardized conditions in the present study. The results show the influence of geometrical aspects of the chamber design on the hydrodynamic and therewith, on the separation efficiency. As a conclusion of the present study, some ideas for an optimal chamber design for laboratory and industrial purpose are proposed. PMID:25766495

  20. Method of breaking and emulsion and an emulsion-emulsion breaker composition

    SciTech Connect

    Salathiel, W. M.

    1985-05-14

    This invention relates to a composition of matter and to a method for producing a controllable, residue-free break of an emulsion or a dispersion of a water-in-oil emulsion. An emulsion breaker is incorporated into the emulsion. It is temporarily-protected (deactivated) so that breaking of the emulsion is initially avoided. By removing the protection, the breaker becomes active, and it acts to break the emulsion into its separate phases.

  1. Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1

    SciTech Connect

    Bieniosek, F.M.; Bieniosek, F.M.; Dickinson, M.R.; Henestroza, E.; Katayanagi, T.; Jung, J.Y.; Lee, C.W.; Leitner, M.; Ni, P.; Roy, P.; Seidl, P.; Waldron, W.; Welch, D.

    2008-06-09

    The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) has completed the fabrication of a new experimental target chamber facility for future Warm Dense Matter (WDM) experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. This achievement provides to the HIFS-VNL unique and state-of-the-art experimental capabilities in preparation for the planned target heating experiments using intense heavy ion beams.

  2. Choice chamber experiments to test the attraction of postflexion Rhabdosargus holubi larvae to water of estuarine and riverine origin

    NASA Astrophysics Data System (ADS)

    James, Nicola C.; Cowley, Paul D.; Whitfield, Alan K.; Kaiser, Horst

    2008-03-01

    Although the recruitment of larvae and juveniles of marine fishes into estuaries has been well documented, little is known about the factors governing the immigration of estuary-associated marine fishes into estuaries. Fishes have a well-developed sense of smell and it has been suggested by several workers that olfactory cues of freshwater or estuarine origin serve as stimuli, attracting larvae and juveniles of estuary-associated species into estuaries. Attraction of postflexion Rhabdosargus holubi larvae to estuary and river water from the Kowie estuarine system, South Africa, was measured using a rectangular choice chamber. In experiments, conducted during peak recruitment periods, larvae selected estuary and river water with a significantly higher frequency than sea water. This study, the first to assess the possible role of olfaction in the recruitment process of an estuary-associated marine fish species, demonstrates that larvae are able to recognise water from different origins, probably based on odour.

  3. Microfluidics with Gel Emulsions

    NASA Astrophysics Data System (ADS)

    Priest, Craig; Surenjav, Enkhtuul; Herminghaus, Stephan; Seemann, Ralf

    2006-03-01

    Microfluidic processing is usually achieved using single phase liquids. Instead, we use monodisperse emulsions to compartment liquids within microchannel geometries. At low continuous phase volume fractions, droplets self-organize to form well-defined arrangements, analogous to foam. While it is well-known that confined geometries can induce rearrangement of foam compartments at the millimeter-scale, similar dynamics are also expected for gel emulsions. We have studied online generation, organization and manipulation of gel emulsions using a variety of microchannel geometries. ``Passive'' reorganization, based on fixed channel geometries, can be supplemented by ``active'' manipulation by incorporating a ferrofluid phase. A ferromagnetic phase facilitates reorganization of liquid compartments on demand using an electromagnetic trigger. Moreover, coalescence between adjacent compartments within a gel emulsion can be induced using electrical potential. Microfluidics using gel emulsions will be well-suited for combinatorial chemistry, DNA sequencing, drug screening and protein crystallizations.

  4. Rheology of emulsions.

    PubMed

    Derkach, Svetlana R

    2009-10-30

    The review is devoted to the historical and modern understanding of rheological properties of emulsions in a broad range of concentration. In the limiting case of dilute emulsions, the discussion is based on the analogy and differences in properties of suspensions and emulsions. For concentrated emulsions, the main peculiarities of their rheological behaviour are considered. Different approaches to understand the concentration dependencies of viscosity are presented and compared. The effects of non-Newtonian flow curves and the apparent transition to yielding with increasing concentration of the dispersed phase are discussed. The problem of droplet deformation in shear fields is touched. The highly concentrated emulsions (beyond the limit of closest packing of spherical particles) are treated as visco-plastic media, and the principle features of their rheology (elasticity, yielding, concentration and droplet size dependencies) are considered. A special attention is paid to the problem of shear stability of drops of an internal phase starting from the theory of the single drop behaviour, including approaches for the estimation of drops' stability in concentrated emulsions. Polymer blends are also treated as emulsions, though taking into account their peculiarities due to the coexistence of two interpenetrated phases. Different theoretical models of deformation of polymer drops were discussed bearing in mind the central goal of predictions of the visco-elastic properties of emulsions as functions of the properties of individual components and the interfacial layer. The role of surfactants is discussed from the point of view of stability of emulsions in time and their special influence on the rheology of emulsions. PMID:19683219

  5. Cationic bituminous emulsions and emulsion aggregate slurries

    SciTech Connect

    Schilling, P.

    1986-07-01

    A cationic bituminous emulsion is described which consists of from about 30% to about 80% by weight of bitumen, from about 0.1% to about 10% by weight of an emulsifier selected from the group consisting of reaction products of a polyamine reacted with a member of the group consisting of epoxidized unsaturated fatty acids of chain lengths between C/sub 8/ and C/sub 22/ and the esters thereof and adding water to make up 100% by weight, the emulsion having a pH in the range of from 2-7.

  6. C{sub 5}{sup A} axial form factor from bubble chamber experiments

    SciTech Connect

    Graczyk, K. M.; Sobczyk, J. T.; Kielczewska, D.; Przewlocki, P.

    2009-11-01

    A careful reanalysis of both Argonne National Laboratory and Brookhaven National Laboratory data for weak single pion production is done. We consider deuteron nuclear effects and normalization (flux) uncertainties in both experiments. We demonstrate that these two sets of data are in good agreement. For the dipole parametrization of C{sub 5}{sup A}(Q{sup 2}), we obtain C{sub 5}{sup A}(0)=1.19{+-}0.08, M{sub A}=0.94{+-}0.03 GeV. As an application we present the discussion of the uncertainty of the neutral current 1{pi}{sup 0} production cross section, important for the T2K neutrino oscillation experiment.

  7. Development of the read-out ASIC for muon chambers of the CBM experiment

    NASA Astrophysics Data System (ADS)

    Atkin, E.; Ivanov, V.; Ivanov, P.; Malankin, E.; Normanov, D.; Osipov, D.; Samsonov, V.; Shumikhin, V.; Voronin, A.

    2015-04-01

    A front-end ASIC for GEM detectors readout in the CBM experiment is presented. The design has the following features: dynamic range of 100 fC, channel hit rate of 2 MHz, ENC of 1000 e- at 50 pF, power comsumption of 10 mW per channel, 6 bit SAR ADC. The chip includes 8 analog processing chains, each consisting of preamplifier, two shapers (fast and slow), differential comparator and an area efficient 6 bit SAR ADC with 1.2 mW power consunption at 50 Msps. The chip also includes the threshold DAC and the digital part.

  8. Fish Oil–Based Lipid Emulsions in the Treatment of Parenteral Nutrition-Associated Liver Disease: An Ongoing Positive Experience123

    PubMed Central

    Premkumar, Muralidhar H.; Carter, Beth A.; Hawthorne, Keli M.; King, Kristi; Abrams, Steven A.

    2014-01-01

    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, Texas in the use of FOLE in treatment of PNALD as presented at the 2013 Experimental Biology meeting. We describe the findings of a single center, prospective, observational study of infants <6 mo of age with PNALD who received parenteral FOLE as monotherapy. A total of 97 infants received FOLE under the compassionate-use protocol for the treatment of PNALD. Eighty-three (86%) survived with resolution of cholestasis and 14 (14%) died. The median conjugated bilirubin (CB) concentration at the initiation of FOLE therapy was 4.8 mg/dL (range 2.1–26). The median time to resolution of cholestasis was 40 d (range 3–158). Compared with infants with mild cholestasis (CB of 2.1–5 mg/dL at the initiation of FOLE), nonsurvivors were significantly more premature and took longer to resolve their cholestasis. Gestational age at birth correlated inversely with CB at the beginning of FOLE and peak CB. Infants with an initial CB >10 mg/dL had a higher mortality rate than infants with an initial CB <5 mg/dL (35% vs. 6%; P < 0.05). Our experience with the use of FOLE in PNALD continues to be encouraging. Prematurity continues to be a major determinant in mortality and severity of cholestasis. This calls for further controlled studies designed to optimize dose and timing of intervention in the use of FOLE in neonates. PMID:24425724

  9. Exposure chamber

    DOEpatents

    Moss, Owen R.; Briant, James K.

    1983-01-01

    An exposure chamber includes an imperforate casing having a fluid inlet at the top and an outlet at the bottom. A single vertical series of imperforate trays is provided. Each tray is spaced on all sides from the chamber walls. Baffles adjacent some of the trays restrict and direct the flow to give partial flow back and forth across the chambers and downward flow past the lowermost pan adjacent a central plane of the chamber.

  10. Insights into aerosol formation chemistry from comprehensive gas-phase precursor measurement in the TRAPOZ chamber experiments; an overview

    NASA Astrophysics Data System (ADS)

    Carr, Timo; Wyche, Kevin; Monks, Paul S.; Camredon, Marie; Alam, Mohammed S.; Bloss, William J.; Rickard, Andrew R.

    2010-05-01

    Aerosols have a profound affect on the environment on local, regional and even global levels, with impacts including adverse health effects, (Alfarra, Paulsen et al. 2006) visibility reduction, cloud formation, direct radiative forcing (Charlson, Schwartz et al. 1992) and an important role in influencing the climate due to their contribution to important atmospheric processes (Baltensperger, Kalberer et al. 2005; Alfarra, Paulsen et al. 2006). The Total Radical Production from the OZonolysis of alkenes (TRAPOZ) project was used to study the gas phase and radical chemistry along with secondary organic aerosol (SOA) formation for a number of different alkenes and terpenes. In order to better the scientific knowledge regarding the oxidation mechanisms of terpene and alkene species along with radical and SOA formation, the experiments were conducted under varying conditions controlled and monitored by the EUropean PHOto REactor (EUPHORE) simulation chamber in Valencia, Spain. A vast number of instruments enabled a detailed examination of the chemistry within oxidation of each precursor. However the work here will focus on the results obtained from the University of Leicester Chemical Ionisation Reaction Time-of-Flight Mass Spectrometer (CIR-TOF-MS). With regard to the gas phase chemistry an analysis of the degradation of the precursor Volatile Organic Compounds (VOCs) and evolution of certain gas phase species in each experiment has been presented and discussed.

  11. Magnetoresistive Emulsion Analyzer

    PubMed Central

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

    2013-01-01

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

  12. Magnetoresistive emulsion analyzer.

    PubMed

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

    2013-01-01

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

  13. Emulsion/Surface Interactions from Quiescent Quartz Crystal Microbalance Measurements with an Inverted Sensor.

    PubMed

    Mafi, Roozbeh; Pelton, Robert H

    2015-07-01

    Interactions of three oil-in-water emulsion types with polystyrene-coated quartz crystal microbalance (QCM) sensor surfaces were probed with the QCM cell in both the conventional orientation (i.e., polystyrene surface on the bottom, "looking up") and the inverted orientation (polystyrene on top interior surface of sensor chamber, "looking down"). With the conventionally oriented QCM sensors, the adsorption of soluble and/or dispersed species quickly gave steady-state frequency and dissipation outputs. By contrast, the inverted sensors gave changing responses at long times because of the gravity driven buildup of a viscous consolidation layer next to but not necessarily bound to the sensor surface. Three emulsion types (a simple hexadecane/phosphatidylcholine emulsion, 2% homogenized milk, and a diluted commercial ophthalmic emulsion) displayed a wide range of behaviors. We propose that quiescent QCM measurement made with an inverted sample chamber is a new approach to probing emulsion behaviors near solid surfaces. PMID:26083783

  14. Exposure chamber

    DOEpatents

    Moss, Owen R.

    1980-01-01

    A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

  15. Paragenesis of Diamond and Minerals of Peridotites and Carbonatites in the Mantle Magma Chambers Based on Experiments Data

    NASA Astrophysics Data System (ADS)

    Kuzyura, Anastasia; Simonova, Dariya; Litvin, Yury

    2014-05-01

    It is considered that role of carbonate melts is important in processes of mantle metasomatism; according to other representations, it is also assumed that they could be formed at partial melting of carbonated peridotite. Dissolving of peridotite minerals and carbon in carbonate melts are responsible for formation of completely miscible carbonate-silicate-carbon magmas parental for diamonds. It can be expected that such carbonate magmas are capable to assimilate an form parental magama "chambers" within the hosting mantle peridotite. While natural cooling of the chambers dissolved in carbonate melts components of the peridotite crystallize forming minerals similar to these of the host mantle peridotite. The recrystallized peridotite minerals are fragmentarily included hermetically within growing diamonds and occur as syngenetic inclusions in them. Therefore experimental modeling of origin of the upper mantle carbonate-silicate diamond-forming melts, their consolidations in the magmatic chambers and evolutions at conditions of equilibrium and fractional crystallization are especially significant for understanding of processes of deep magmatic petrology and genetic mineralogy, including genesis of diamond. In the study at 6 GPa model approximations of mineral phases, significant in compositions of probable metasomatic agents, the upper mantle peridotites, and also syngenetic inclusions in diamonds were used: starting mixtures were model peridotite with composition Ol48Opx16Cpx16Grt20, close to model compositions of the primitive mantle and real mantle xenolithes, as well as multicomponent carbonate (CaCO3)20(Na2CO3)20(FeCO3)20(Na2CO3)20(K2CO3)20 modeling carbonatite inclusions in natural diamonds. Spectral pure graphite was used as a source of carbon in the system. Pressure and temperature were reached using apparatus of toroidal type 'anvil-with-hole'. Electron microprobe and SEM researches were carried out on the polished surfaces with carbon covering at IEM RAS

  16. Bromine Explosions In Smog Chamber Experiments: A comparison of Cavity-Enhanced (CE) and White-cell DOAS

    NASA Astrophysics Data System (ADS)

    Buxmann, J.; Hoch, D. J.; Sihler, H.; Pöhler, D.; Platt, U.; Bleicher, S.; Balzer, N.; Zetzsch, C.

    2011-12-01

    Reactive halogen species (RHS), such as Cl, Br or BrO, can significantly influence chemical processes in the troposphere, including the destruction of ozone, change in the chemical balance of hydrogen radicals (OH, HO2), increased deposition of toxic compounds (like mercury) with potential consequences for the global climate. Previous studies have shown that salt lakes can be significant sources for gaseous RHS. Environmental conditions such as salt composition, relative humidity (RH), pH, and temperature (T) can strongly influence reactive bromine levels, but are difficult to quantify in the field. Therefore, we conducted laboratory experiments by exposing NaCl salt containing 0.33% (by weight) NaBr to simulated sunlight in a Teflon smog-chamber under various conditions of RH and ozone concentrations. BrO levels were observed by a Differential-Optical-Absorption-Spectrometer (DOAS) in combination with a multi-reflection cell (White-cell). The concentrations of OH- and Cl- radicals were quantified by the radical clock method. We present the first direct observation of BrO from the "Bromine Explosion" (auto catalytic release of reactive bromine from salt surfaces - key to ozone destruction) in the laboratory above a simulated salt pan. The maximum BrO mixing ratio of 6419±71 ppt at 60% RH was observed to be one order of magnitude higher than at 37% RH and 2% RH. The release of RHS from the salt pan is possibly controlled by the thickness of the quasi liquid layer, covering the reactive surface of the halide crystals, as the layer thickness strongly depends on RH. Furthermore, a new cavity enhanced DOAS (CE-DOAS) instrument was designed and successfully used in chamber experiments. For the first time, such an instrument uses a spectral interval in the UV - wavelength range (325-365 nm) to identify BrO. We show a comparison of the CE-DOAS and White-cell DOAS instrument in a series of experiments, where e.g. a peak BrO mixing ratio up to 380 ppt within the first

  17. [Proposal of a cloud chamber experiment using diagnostic X-ray apparatus and an analysis assisted by a simulation code].

    PubMed

    Hayashi, Hiroaki; Hanamitsu, Hiroki; Nishihara, Sadamitsu; Ueno, Junji; Miyoshi, Hirokazu

    2013-04-01

    A cloud chamber is a radiation detector that can visualize the tracks of charged particles. In this study, we developed a middle-type cloud chamber for use in practical training using a diagnostic X-ray apparatus. Because our cloud chamber has a heater to vaporize ethanol and features antifogging glass, it is possible to observe the vapor trails for a long time without the need for fine adjustments. X-rays with a tube voltage of 40 kV or of 120 kV (with a 21-mm aluminum filter) were irradiated at the chamber and the various phenomena were observed. We explain these phenomena in terms of the range of electrons and/or interactions between X-rays and matter and conclude that our analysis is consistent with analysis using the Monte Carlo simulation code EGS5. PMID:23609860

  18. Wire chamber

    DOEpatents

    Atac, Muzaffer

    1989-01-01

    A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

  19. 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.

  20. Magnetofluid emulsion: New magnetocontrolled media

    NASA Astrophysics Data System (ADS)

    Bashtovoi, Victor G.; Yarmolchik, Yuri P.

    1994-03-01

    This study has shown that flow dynamics of emulsion consisting of magnetic and nonmagnetic fluids depends on applied magnetic field. So these emulsions may be considered as a magnetic field controlled medium, and in particular as a magnetic field controlled heat carrier. The new dates on rheological properties of these emulsions in the presence of magnetic field are described.

  1. 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.

  2. IONIZATION CHAMBER

    DOEpatents

    Redman, W.C.; Shonka, F.R.

    1958-02-18

    This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

  3. NEWS: Nuclear emulsion WIMP search

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

    The most convincing candidate as main constituent of the dark matter in the Universe consists of Weakly Interacting Massive Particles (WIMPs). WIMPs must be electrically neutral and interact with a very low cross-section ( σ<10^{-40} cm2) which makes them detectable in direct searches only through the observation of nuclear recoils induced by the WIMP rare scatterings. In the experiments carried out so far, recoiled nuclei are searched for as a signal over a background produced by Compton electrons and neutron scatterings. Signal found by some experiments have not been confirmed by other techniques. We propose an R&D program for a new experimental method able to observe the track of the scattered nucleus based on new developments in the nuclear emulsion technique. Nuclear emulsions would act both as the WIMP target and as the tracking detector able to reconstruct the direction of the recoiled nucleus. This unique characteristic would provide a new and unambiguous signature of the presence of the dark matter in our galaxy.

  4. Evaluation of one-dimensional and two-dimensional volatility basis sets in simulating the aging of secondary organic aerosol with smog-chamber experiments.

    PubMed

    Zhao, Bin; Wang, Shuxiao; Donahue, Neil M; Chuang, Wayne; Hildebrandt Ruiz, Lea; Ng, Nga L; Wang, Yangjun; Hao, Jiming

    2015-02-17

    We evaluate the one-dimensional volatility basis set (1D-VBS) and two-dimensional volatility basis set (2D-VBS) in simulating the aging of SOA derived from toluene and α-pinene against smog-chamber experiments. If we simulate the first-generation products with empirical chamber fits and the subsequent aging chemistry with a 1D-VBS or a 2D-VBS, the models mostly overestimate the SOA concentrations in the toluene oxidation experiments. This is because the empirical chamber fits include both first-generation oxidation and aging; simulating aging in addition to this results in double counting of the initial aging effects. If the first-generation oxidation is treated explicitly, the base-case 2D-VBS underestimates the SOA concentrations and O:C increase of the toluene oxidation experiments; it generally underestimates the SOA concentrations and overestimates the O:C increase of the α-pinene experiments. With the first-generation oxidation treated explicitly, we could modify the 2D-VBS configuration individually for toluene and α-pinene to achieve good model-measurement agreement. However, we are unable to simulate the oxidation of both toluene and α-pinene with the same 2D-VBS configuration. We suggest that future models should implement parallel layers for anthropogenic (aromatic) and biogenic precursors, and that more modeling studies and laboratory research be done to optimize the "best-guess" parameters for each layer. PMID:25581402

  5. Nano-emulsions of fluorinated trityl radicals as sensors for EPR oximetry

    NASA Astrophysics Data System (ADS)

    Charlier, N.; Driesschaert, B.; Wauthoz, N.; Beghein, N.; Préat, V.; Amighi, K.; Marchand-Brynaert, J.; Gallez, B.

    2009-04-01

    This article reports the development and evaluation of two nano-emulsions (F45T-03/HFB and F15T-03/PFOB) containing fluorinated trityl radicals dissolved in perfluorocarbons. Preparation with a high-pressure homogenizer conferred sub-micronic size to both nano-emulsions. In vitro and in vivo EPR spectroscopy showed that the nano-emulsions had much greater oxygen sensitivity than the hydrophilic trityl, CT-03. In vivo experiments in rodents confirmed the ability of the nano-emulsions to follow the changes in oxygen concentration after induced ischemia. Histological evaluation of the tissue injected with the nano-emulsions revealed some acute toxicity for the F45T-03/HFB nano-emulsion but none for the F15T-03/PFOB nano-emulsion. These new formulations should be considered for further EPR oximetry experiments in pathophysiological situations where subtle changes in tissue oxygenation are expected.

  6. Nano-emulsions of fluorinated trityl radicals as sensors for EPR oximetry.

    PubMed

    Charlier, N; Driesschaert, B; Wauthoz, N; Beghein, N; Préat, V; Amighi, K; Marchand-Brynaert, J; Gallez, B

    2009-04-01

    This article reports the development and evaluation of two nano-emulsions (F45T-03/HFB and F15T-03/PFOB) containing fluorinated trityl radicals dissolved in perfluorocarbons. Preparation with a high-pressure homogenizer conferred sub-micronic size to both nano-emulsions. In vitro and in vivo EPR spectroscopy showed that the nano-emulsions had much greater oxygen sensitivity than the hydrophilic trityl, CT-03. In vivo experiments in rodents confirmed the ability of the nano-emulsions to follow the changes in oxygen concentration after induced ischemia. Histological evaluation of the tissue injected with the nano-emulsions revealed some acute toxicity for the F45T-03/HFB nano-emulsion but none for the F15T-03/PFOB nano-emulsion. These new formulations should be considered for further EPR oximetry experiments in pathophysiological situations where subtle changes in tissue oxygenation are expected. PMID:19128993

  7. Emulsion detectors for the antihydrogen detection in AEgIS

    NASA Astrophysics Data System (ADS)

    Pistillo, C.; Aghion, S.; Amsler, C.; Ariga, A.; Ariga, T.; Belov, A.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R. S.; Cabaret, L.; Caccia, M.; Caravita, R.; Castelli, F.; Cerchiari, G.; Chlouba, K.; Cialdi, S.; Comparat, D.; Consolati, G.; Demetrio, A.; Derking, H.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Ferragut, R.; Fontana, A.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Gninenko, S.; Haider, S.; Hogan, S.; Holmestad, H.; Huse, T.; Jordan, E. J.; Kawada, J.; Kellerbauer, A.; Kimura, M.; Krasnický, D.; Lagomarsino, V.; Lehner, S.; Malbrunot, C.; Mariazzi, S.; Matveev, V.; Mazzotta, Z.; Nebbia, G.; Nédélec, P.; Oberthaler, M.; Pacifico, N.; Penasa, L.; Petráček, V.; Prelz, F.; Prevedelli, M.; Ravelli, L.; Riccardi, C.; Røhne, O.; Rosenberger, S.; Rotondi, A.; Sandaker, H.; Santoro, R.; Scampoli, P.; Simon, M.; Špaček, M.; Storey, J.; Strojek, I. M.; Subieta, M.; Testera, G.; Widmann, E.; Yzombard, P.; Zavatarelli, S.; Zmeskal, J.

    2015-08-01

    The AEgIS experiment at CERN aims to perform the first direct measurement of gravitational interaction between matter and antimatter by measuring the deviation of a cold antihydrogen beam in the Earth gravitational field. The design of the experiment has been recently updated to include emulsion films as position sensitive detector. The submicrometric position accuracy of emulsions leads indeed to a significant improvement of the experimental sensitivity. We present results of preliminary tests and discuss perspectives for the final measurement.

  8. An ultra-high vacuum chamber for scattering experiments featuring in-vacuum continuous in-plane variation of the angle between entrance and exit vacuum ports

    SciTech Connect

    Englund, Carl-Johan; Agåker, Marcus Fredriksson, Pierre; Olsson, Anders; Johansson, Niklas; Rubensson, Jan-Erik; Nordgren, Joseph

    2015-09-15

    A concept that enables in-vacuum continuous variation of the angle between two ports in one plane has been developed and implemented. The vacuum chamber allows for measuring scattering cross sections as a function of scattering angle and is intended for resonant inelastic X-ray scattering experiments. The angle between the ports can be varied in the range of 30°-150°, while the pressure change is less than 2 × 10{sup −10} mbars.

  9. Simulation of SOA formation and composition from oxidation of toluene and m-xylene in chamber experiments

    NASA Astrophysics Data System (ADS)

    Xu, J.; Liu, Y.; Nakao, S.; Cocker, D.; Griffin, R. J.

    2013-12-01

    Aromatic hydrocarbons contribute an important fraction of anthropogenic reactive volatile organic compounds (VOCs) in the urban atmosphere. Photo-oxidation of aromatic hydrocarbons leads to secondary organic products that have decreased volatilities or increased solubilities and can form secondary organic aerosol (SOA). Despite the crucial role of aromatic-derived SOA in deteriorating air quality and harming human health, its formation mechanism is not well understood and model simulation of SOA formation still remains difficult. The dependence of aromatic SOA formation on nitrogen oxides (NOx) is not captured fully by most SOA formation models. Most models predict SOA formation under high NOx levels well but underestimate SOA formation under low NOx levels more representative of the ambient atmosphere. Thus, it is crucial to investigate the NOx-dependent chemistry in aromatic photo-oxidation systems and correspondingly update SOA formation models. In this study, NOx-dependent mechanisms of toluene and m-xylene SOA formation are updated using the gas-phase Caltech Atmospheric Chemistry Mechanism (CACM) coupled to a gas/aerosol partitioning model. The updated models were optimized by comparing to eighteen University of California, Riverside United States Environmental Protection Agency (EPA) chamber experiment runs under both high and low NOx conditions. Correction factors for vapor pressures imply uncharacterized aerosol-phase association chemistry. Simulated SOA speciation implies the importance of ring-opening products in governing SOA formation (up to 40%~60% for both aromatics). The newly developed model can predict strong decreases of m-xylene SOA yield with increasing NOx. Speciation distributions under varied NOx levels implies that the well-known competition between RO2 + HO2 and RO2 + NO (RO2 = peroxide bicyclic radical) may not be the only factor influencing SOA formation. The reaction of aromatic peroxy radicals with NO competing with its self

  10. 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.

  11. Charge Identification of Highly Ionizing Particles in Desensitized Nuclear Emulsion Using High Speed Read-Out System

    SciTech Connect

    Toshito, T.; Kodama, K.; Yusa, K.; Ozaki, M.; Amako, K.; Kameoka, S.; Murakami, K.; Sasaki, T.; Aoki, S.; Ban, T.; Fukuda, T.; Naganawa, N.; Nakamura, T.; Natsume, M.; Niwa, K.; Takahashi, S.; Kanazawa, M.; Kanematsu, N.; Komori, M.; Sato, S.; Asai, M.; /Nagoya U. /Aichi U. of Education /Gunma U., Maebashi /JAXA, Sagamihara /KEK, Tsukuba /Kobe U. /Chiba, Natl. Inst. Rad. Sci. /SLAC /Toho U.

    2006-05-10

    We performed an experimental study of charge identification of heavy ions from helium to carbon having energy of about 290 MeV/u using an emulsion chamber. Emulsion was desensitized by means of forced fading (refreshing) to expand a dynamic range of response to highly charged particles. For the track reconstruction and charge identification, the fully automated high speed emulsion read-out system, which was originally developed for identifying minimum ionizing particles, was used without any modification. Clear track by track charge identification up to Z=6 was demonstrated. The refreshing technique has proved to be a powerful technique to expand response of emulsion film to highly ionizing particles.

  12. SMOG CHAMBER VALIDATION USING LAGRANGIAN ATMOSPHERIC DATA

    EPA Science Inventory

    A method was developed for validating outdoor smog chamber experiments as a means of determining the relationships between oxidant concentrations and its precursors - hydrocarbons and nitrogen oxides. When chamber experiments were performed in a manner that simulated relevant met...

  13. 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

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

    PubMed

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

    2014-11-01

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

  15. Overview of the Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT): mechanistic chamber studies on the oxidation of biogenic compounds

    DOE PAGESBeta

    Nguyen, T. B.; Crounse, J. D.; Schwantes, R. H.; Teng, A. P.; Bates, K. H.; Zhang, X.; St. Clair, J. M.; Brune, W. H.; Tyndall, G. S.; Keutsch, F. N.; et al

    2014-12-19

    The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative atmospheric chamber campaign that occurred during January 2014. FIXCIT is the laboratory component of a synergistic field and laboratory effort aimed toward (1) better understanding the chemical details behind ambient observations relevant to the southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. Approximately 20 principal scientists from 14 academic and government institutions performed parallel measurements at a forested site in Alabama and at the atmospheric chambers at Caltech.more » During the 4 week campaign period, a series of chamber experiments was conducted to investigate the dark- and photo-induced oxidation of isoprene, α-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX) in a highly controlled and atmospherically relevant manner. Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized and contributed by campaign participants, which enabled explicit exploration into the oxidation mechanisms and instrument responses for these important atmospheric compounds. The present overview describes the goals, experimental design, instrumental techniques, and preliminary observations from the campaign. This work provides context for forthcoming publications affiliated with the FIXCIT campaign. Insights from FIXCIT are anticipated to aid significantly in interpretation of field data and the revision of mechanisms currently implemented in regional and global atmospheric models.« less

  16. Overview of the Focused Isoprene eXperiments at California Institute of Technology (FIXCIT): mechanistic chamber studies on the oxidation of biogenic compounds

    DOE PAGESBeta

    Nguyen, T. B.; Crounse, J. D.; Schwantes, R. H.; Teng, A. P.; Bates, K. H.; Zhang, X.; St. Clair, J. M.; Brune, W. H.; Tyndall, G. S.; Keutsch, F. N.; et al

    2014-08-25

    The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative atmospheric chamber campaign that occurred during January 2014. FIXCIT was the laboratory component of a synergistic field and laboratory effort aimed toward (1) better understanding the chemical details behind ambient observations relevant to the Southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. Approximately 20 principal scientists from 14 academic and government institutions performed parallel measurements at a forested site in Alabama and at the atmospheric chambers at Caltech.more » During the four-week campaign period, a series of chamber experiments was conducted to investigate the dark- and photo-induced oxidation of isoprene, α-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX) in a highly-controlled and atmospherically-relevant manner. Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized and contributed by campaign participants, which enabled explicit exploration into the oxidation mechanisms and instrument responses for these important atmospheric compounds. The present overview describes the goals, experimental design, instrumental techniques, and preliminary observations from the campaign. Insights from FIXCIT are anticipated to significantly aid in interpretation of field data and the revision of mechanisms currently implemented in regional and global atmospheric models.« less

  17. Ionization chamber

    DOEpatents

    Walenta, Albert H.

    1981-01-01

    An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

  18. Ionization chamber

    DOEpatents

    Walenta, A.H.

    An ionization chamber is described which has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionizes the gas.

  19. Automated microbial metabolism laboratory. [design of advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into test chambers

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The design and rationale of an advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into each of four test chambers are outlined. The feasibility for multiple addition tests was established and various details of the methodology were studied. The four chamber battery of tests include: (1) determination of the effect of various atmospheric gases and selection of that gas which produces an optimum response; (2) determination of the effect of incubation temperature and selection of the optimum temperature for performing Martian biochemical tests; (3) sterile soil is dosed with a battery of C-14 labeled substrates and subjected to experimental temperature range; and (4) determination of the possible inhibitory effects of water on Martian organisms is performed initially by dosing with 0.01 ml and 0.5 ml of medium, respectively. A series of specifically labeled substrates are then added to obtain patterns in metabolic 14CO2 (C-14)O2 evolution.

  20. Outdoor smog chamber experiments: reactivity of methanol exhaust. Part 2. Quality assurance and data processing system description

    SciTech Connect

    Jeffries, H.E.; Sexton, K.G.; Kamens, R.M.; Holleman, M.S.

    1985-09-01

    The report describes the Quality Assurance and Data Processing procedures and systems used at the UNC Outdoor Smog Chamber Facility. The primary product of research conducted at this facility is information in the form of measurements of reactants and products in photochemical systems and measurements of the critical parameters that influence the chemical transformations system. Generating useful data begins with understanding the goals of the project and the special needs and concerns of conducting a successful smog-chamber operation. The system components are designed to collect, transfer, process, and report accurate, high-resolution data without loss or distortion. The system components in the Quality Assurance and Data Processing system are: people, hardware, software, checklists, and data bases. Quality-assurance checks are made at every level of the program. Pressurized gas-tank and liquid mixtures were used to establish experimental conditions of HC assuring consistency throughout the program. Several NBS traceable standards and liquid injections into the chamber used for calibration have been intercompared and show good agreement.

  1. Double Emulsion Templated Celloidosomes

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  2. 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)

  3. Pickering emulsions with controllable stability.

    PubMed

    Melle, Sonia; Lask, Mauricio; Fuller, Gerald G

    2005-03-15

    We prepare solid-stabilized emulsions using paramagnetic particles at an oil/water interface that can undergo macroscopic phase separation upon application of an external magnetic field. A critical field strength is found for which emulsion droplets begin to translate into the continuous-phase fluid. At higher fields, the emulsions destabilize, leading to a fully phase-separated system. This effect is reversible, and long-term stability can be recovered by remixing the components with mechanical agitation. PMID:15752002

  4. Oil-in-oil emulsions stabilised solely by solid particles.

    PubMed

    Binks, Bernard P; Tyowua, Andrew T

    2016-01-21

    A brief review of the stabilisation of emulsions of two immiscible oils is given. We then describe the use of fumed silica particles coated with either hydrocarbon or fluorocarbon groups in acting as sole stabilisers of emulsions of various vegetable oils with linear silicone oils (PDMS) of different viscosity. Transitional phase inversion of emulsions, containing equal volumes of the two oils, from silicone-in-vegetable (S/V) to vegetable-in-silicone (V/S) occurs upon increasing the hydrophobicity of the particles. Close to inversion, emulsions are stable to coalescence and gravity-induced separation for at least one year. Increasing the viscosity of the silicone oil enables stable S/V emulsions to be prepared even with relatively hydrophilic particles. Predictions of emulsion type from calculated contact angles of a silica particle at the oil-oil interface are in agreement with experiment provided a small polar contribution to the surface energy of the oils is included. We also show that stable multiple emulsions of V/S/V can be prepared in a two-step procedure using two particle types of different hydrophobicity. At fixed particle concentration, catastrophic phase inversion of emulsions from V/S to S/V can be effected by increasing the volume fraction of vegetable oil. Finally, in the case of sunflower oil + 20 cS PDMS, the study is extended to particles other than silica which differ in chemical type, particle size and particle shape. Consistent with the above findings, we find that only sufficiently hydrophobic particles (clay, zinc oxide, silicone, calcium carbonate) can act as efficient V/S emulsion stabilisers. PMID:26549699

  5. On a possibility of inelasticity partial coefficient K sub gamma determination in pi C and pi Pb interactions at 10 to the 14th power eV (experiment PAMIR 1)

    NASA Technical Reports Server (NTRS)

    Borisov, A. S.; Cherdyntseva, K. V.; Guseva, Z. M.; Denisova, V. G.; Dunaevsky, A. M.; Kanevskaya, E. A.; Maximenko, V. M.; Nam, R. A.; Pashkov, S. V.; Puchkov, V. S.

    1985-01-01

    The investigation of hadron-nuclear interactions in Pamir experiment is carried out by means of X-ray emulsion chambers of two types: carbon (C) and lead (Pb). While comparing the results from the chambers of both types it was found a discrepancy in n sub h and E sub h(1)R values. The observed discrepancy in C and Pb chambers is connected with the difference in values of effective coefficients of energy transfer to the soft component K sub eff for C and Pb chambers.

  6. 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.

  7. Magma chambers

    NASA Technical Reports Server (NTRS)

    Marsh, Bruce D.

    1989-01-01

    Recent observational and theoretical investigations of terrestrial magma chambers (MCs) are reviewed. Consideration is given to the evidence for MCs with active convection and crystal sorting, problems of direct MC detection, theoretical models of MC cooling, the rheology and dynamics of solidification fronts, crystal capture and differentiation, convection with solidification, MC wall flows, and MC roof melting. Diagrams, graphs, and a list of problems requiring further research are provided.

  8. 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

  9. Produced fluid emulsions. Final report

    SciTech Connect

    Hurley, C.F.; Himmelblau, A.; Trom, L.

    1984-09-01

    Emulsion production and stabilization may be due to one or more of several phenomenon including water-oil ratio, oil and brine chemistry, and surfactant and polymer type and concentration. They may influence emulsification either independently or with dependence on one or more of the other factors. Task One has tried to define which factors are dominant and what effect variations in them will have on the emulsion characteristics for each of the fields investigated. Emulsions were produced using a hand homogenizer at a fixed setting for a specific length of time to ensure all samples were produced uniformly. A du Nouy apparatus was used to measure surface and interfacial tensions and a binocular microscope was used in the micro-visual studies. The emulsions were treated in a similar manner with a wide variety of materials to not only break them, but also to help define which mechanisms are responsible for the stabilization of a particular emulsion. Core floods in Task Two utilized a six-foot sand-pack for a mixing medium. A six-inch long Berea core which followed, provided shear similar to that of the reservoir. The choice of oil, brine, surfactant and polymer were chosen to correlate to the Task One studies. Similarities and differences in the results between the bench-top and core flood studies are noted. The conditions of emulsion production and characteristics and the effectiveness of emulsion breakers are compared to help determine the mechanism of emulsion stabilization. 8 figures, 85 tables.

  10. Beam Window for Pressure Chambers

    NASA Technical Reports Server (NTRS)

    Bransford, J. W.; Austin, J. G., Jr.

    1985-01-01

    Window resists products of combustion experiments. Sodium chloride window seals over chamber pressures from 0.1 to 13.8 MPa while absorbing minimal energy from CO2 laser beam that passes through it into chamber. Window inexpensive and easily replacable.

  11. Automated Electrostatics Environmental Chamber

    NASA Technical Reports Server (NTRS)

    Calle, Carlos; Lewis, Dean C.; Buchanan, Randy K.; Buchanan, Aubri

    2005-01-01

    The Mars Electrostatics Chamber (MEC) is an environmental chamber designed primarily to create atmospheric conditions like those at the surface of Mars to support experiments on electrostatic effects in the Martian environment. The chamber is equipped with a vacuum system, a cryogenic cooling system, an atmospheric-gas replenishing and analysis system, and a computerized control system that can be programmed by the user and that provides both automation and options for manual control. The control system can be set to maintain steady Mars-like conditions or to impose temperature and pressure variations of a Mars diurnal cycle at any given season and latitude. In addition, the MEC can be used in other areas of research because it can create steady or varying atmospheric conditions anywhere within the wide temperature, pressure, and composition ranges between the extremes of Mars-like and Earth-like conditions.

  12. Background Simulation of a Fission Fragment Chamber in the Experiment of 209Bi(e, e'K+)209ΛPb

    NASA Astrophysics Data System (ADS)

    Song, Yushou; Liu, Huilan; Xi, Yinyin; Yan, Qiang; Hu, Bitao

    2012-05-01

    An experiment for measuring the hyperon-related fission rate was carried out with the reaction 209Bi(e, e'K+)209ΛPb at the Thomas Jefferson National Laboratory (Jlab). In the experiment, the performance of the fission fragment detector (FFD) was dramatically crashed by the background particles in comparison with that during the test without beam. The scattering of the high intensity (500 nA) primary electrons was the dominant cause. Using the GEANT4 toolkit, this report simulates the experimental situation of the target chamber in which the FFD was located. The simulation results indicate that the background particles were dominantly δ electrons, and protons and alpha particles were the important heavy background particles. The performance of the multi-wire proportional chambers (MWPCs) depends not only on the background-particle intensity but also the current density, which was also given by the simulation code. Furthermore, the measures to suppress the background particles were also investigated with the simulation code.

  13. 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. PMID:25865459

  14. 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. PMID:24704153

  15. Investigation of effects of Giardia duodenalis on transcellular and paracellular transport in enterocytes using in vitro Ussing chamber experiments.

    PubMed

    Tysnes, Kristoffer R; Robertson, Lucy J

    2015-04-01

    The mechanisms by which different genotypes of Giardia duodenalis result in different symptoms remain unresolved. In particular, we lack detailed knowledge on which transport mechanisms (transcellular or paracellular) are affected by different Giardia isolates. Using horse radish peroxidase (HRP) and creatinine as transcellular and paracellular probes, respectively, we developed a robust assay that can be used with an Ussing chamber to investigate epithelial transport, as well as short-circuit current as an indicator of net ion transport. We investigated 2 Giardia isolates, both Assemblage A, one a lab-adapted strain and the other a field isolate. Results indicate that products from sonicated Giardia trophozoites increase both transcellular and paracellular transport. A non-significant increase in transepithelial electrical resistance (TEER) and short-circuit current were also noted. The paracellular transport was increased significantly more in the field isolate than in the lab-adapted strain. Our results indicate that while both transcellular and paracellular transport mechanisms may be increased following exposure of cells to Giardia trophozoite sonicate, perhaps by inducing non-specific increases in cellular traffic, it is important that in vitro studies of Giardia pathophysiology are conducted with different Giardia isolates, not just lab-attenuated strains. PMID:25395017

  16. Competitive adsorption/desorption of tetracycline, oxytetracycline and chlortetracycline on two acid soils: Stirred flow chamber experiments.

    PubMed

    Fernández-Calviño, David; Bermúdez-Couso, Alipio; Arias-Estévez, Manuel; Nóvoa-Muñoz, Juan Carlos; Fernández-Sanjurjo, Maria J; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-09-01

    The objective of this work was to study the competitive adsorption/desorption of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) on two acid soils. We used the stirred flow chamber technique to obtain experimental data on rapid kinetic processes affecting the retention/release of the antibiotics. Both adsorption and desorption were higher on soil 1 (which showed the highest carbon, clay and Al and Fe oxides content) than on soil 2. Moreover, hysteresis affected the adsorption/desorption processes. Experimental data were fitted to a pseudo-first order equation, resulting qamax (adsorption maximum) values that were higher for soil 1 than for soil 2, and indicating that CTC competed with TC more intensely than OTC in soil 1. Regarding soil 2, the values corresponding to the adsorption kinetics constants (ka) and desorption kinetics constants for fast sites (kd1), followed a trend inverse to qamax and qdmax respectively. In conclusion, competition affected adsorption/desorption kinetics for the three antibiotics assayed, and thus retention/release and subsequent transport processes in soil and water environments. PMID:25973861

  17. Formation and stability of polychlorinated biphenyl Pickering emulsions

    NASA Astrophysics Data System (ADS)

    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 ( ϕoil)=30 vol.%; solid concentration ( χ)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 μm, 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.

  18. Preparation of Pickering double emulsions using block copolymer worms.

    PubMed

    Thompson, Kate L; Mable, Charlotte J; Lane, Jacob A; Derry, Mathew J; Fielding, Lee A; Armes, Steven P

    2015-04-14

    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

  19. 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

  20. A fast automatic plate changer for the analysis of nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Balestra, S.; Bertolin, A.; Bozza, C.; Calligola, P.; Cerroni, R.; D'Ambrosio, N.; Degli Esposti, L.; De Lellis, G.; De Serio, M.; Di Capua, F.; Di Crescenzo, A.; Di Ferdinando, D.; Di Marco, N.; Dusini, S.; Esposito, L. S.; Fini, R. A.; Giacomelli, G.; Giacomelli, R.; Grella, G.; Ieva, M.; Kose, U.; Longhin, A.; Mandrioli, G.; Mauri, N.; Medinaceli, E.; Monacelli, P.; Muciaccia, M. T.; Pasqualini, L.; Pastore, A.; Patrizii, L.; Pozzato, M.; Pupilli, F.; Rescigno, R.; Rosa, G.; Ruggieri, A.; Russo, A.; Sahnoun, Z.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Stellacci, S. M.; Strolin, P.; Tenti, M.; Tioukov, V.; Togo, V.; Valieri, C.

    2013-07-01

    This paper describes the design and performance of a computer controlled emulsion Plate Changer for the automatic placement and removal of nuclear emulsion films for the European Scanning System microscopes. The Plate Changer is used for mass scanning and measurement of the emulsions of the OPERA neutrino oscillation experiment at the Gran Sasso lab on the CNGS neutrino beam. Unlike other systems it works with both dry and oil objectives. The film changing takes less than 20 s and the accuracy on the positioning of the emulsion films is about 10 μm. The final accuracy in retrieving track coordinates after fiducial marks measurement is better than 1 μm.

  1. Protein Fibrils Induce Emulsion Stabilization.

    PubMed

    Peng, Jinfeng; Simon, Joana Ralfas; Venema, Paul; van der Linden, Erik

    2016-03-01

    The behavior of an oil-in-water emulsion was studied in the presence of protein fibrils for a wide range of fibril concentrations by using rheology, diffusing wave spectroscopy, and confocal laser scanning microscopy. Results showed that above a minimum fibril concentration depletion flocculation occurred, leading to oil droplet aggregation and enhanced creaming of the emulsion. Upon further increasing the concentration of the protein fibrils, the emulsions were stabilized. In this stable regime both aggregates of droplets and single droplets are present, and these aggregates are smaller than the aggregates in the flocculated emulsion samples at the lower fibril concentrations. The size of the droplet aggregates in the stabilized emulsions is independent of fibril concentration. In addition, the droplet aggregation was reversible upon dilution both by a pH 2 HCl solution and by a fibril solution at the same concentration. The viscosity of the emulsions containing fibrils was comparable to that of the pure fibril solution. Neither fibril networks nor droplet gel networks were observed in our study. The stabilization mechanism of emulsions containing long protein fibrils at high protein fibril concentrations points toward the mechanism of a kinetic stabilization. PMID:26882086

  2. Neutron detection via bubble chambers.

    PubMed

    Jordan, D V; Ely, J H; Peurrung, A J; Bond, L J; Collar, J I; Flake, M; Knopf, M A; Pitts, W K; Shaver, M; Sonnenschein, A; Smart, J E; Todd, L C

    2005-01-01

    Research investigating the application of pressure-cycled bubble chambers to fast neutron detection is described. Experiments with a Halon-filled chamber showed clear sensitivity to an AmBe neutron source and insensitivity to a (137)Cs gamma source. Bubble formation was documented using high-speed photography, and a ceramic piezo-electric transducer element registered the acoustic signature of bubble formation. In a second set of experiments, the bubble nucleation response of a Freon-134a chamber to an AmBe neutron source was documented with high-speed photography. PMID:16005238

  3. Removal of metals and water-insoluble materials from desalter emulsions

    SciTech Connect

    Goyal, S.K.; Mosby, J.F.; Treadman, J.E. II.

    1993-06-15

    A process for removing metals and insoluble materials from crude oil is described comprising the steps of: blending crude oil with water and desalting chemicals; charging the oil blend to a desalting chamber and passing it through an electrical field whereby agglomeration of suspended insoluble materials occurs and layers of clean oil, brine and oil-brine interface emulsion are formed; withdrawing the oil and brine; measuring the volume of the emulsion layer; withdrawing a portion of the emulsion layer; blending the withdrawn emulsion with up to 2 volumes of aromatic-rich hydrocarbon containing at least 20% aromatics by volume; maintaining the blend at a temperature of 100 to 300 F and a positive pressure; and subjecting the blend to a force of at least about 500 g, whereby oil free of at least 90% of suspended particulates and water results.

  4. 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.

  5. Chamber dynamic research with pulsed power

    SciTech Connect

    PETERSON,ROBERT R.; OLSON,CRAIG L.; RENK,TIMOTHY J.; ROCHAU,GARY E.; SWEENEY,MARY ANN

    2000-05-15

    In Inertial Fusion Energy (IFE), Target Chamber Dynamics (TCD) is an integral part of the target chamber design and performance. TCD includes target output deposition of target x-rays, ions and neutrons in target chamber gases and structures, vaporization and melting of target chamber materials, radiation-hydrodynamics in target chamber vapors and gases, and chamber conditions at the time of target and beam injections. Pulsed power provides a unique environment for IFE-TCD validation experiments in two important ways: they do not require the very clean conditions which lasers need and they currently provide large x-ray and ion energies.

  6. Laboratory chamber experiments exploring the potential use of artificially ionized layers of gas as a Bragg reflector for over-the-horizon signals

    NASA Astrophysics Data System (ADS)

    Kuo, S. P.; Zhang, Y. S.; Lee, M. C.; Kossey, Paul; Barker, Robert J.

    1992-12-01

    A set of parallel plasma layers is generated by two intersecting microwave pulses in a chamber containing dry air at a pressure comparable to the upper atmosphere. The dependence of the breakdown conditions on the pressure and pulse length is examined. The results are shown to be consistent with the appearance of tail erosion of microwave pulse caused by air breakdown. Bragg scattering experiments, using the plasma layers as a Bragg reflector are then performed. Both time domain and frequency domain measurements of wave scattering are conducted. The experimental results are found to agree very well with the theory. Moreover, the time domain measurement of wave scattering provides an unambiguous way for determining the temporal evolution of electron density during the first 100-microsec period.

  7. Laboratory chamber experiments exploring the potential use of artificially ionized layers of gas as a Bragg reflector for over-the-horizon signals

    NASA Technical Reports Server (NTRS)

    Kuo, S. P.; Zhang, Y. S.; Lee, M. C.; Kossey, Paul; Barker, Robert J.

    1992-01-01

    A set of parallel plasma layers is generated by two intersecting microwave pulses in a chamber containing dry air at a pressure comparable to the upper atmosphere. The dependence of the breakdown conditions on the pressure and pulse length is examined. The results are shown to be consistent with the appearance of tail erosion of microwave pulse caused by air breakdown. Bragg scattering experiments, using the plasma layers as a Bragg reflector are then performed. Both time domain and frequency domain measurements of wave scattering are conducted. The experimental results are found to agree very well with the theory. Moreover, the time domain measurement of wave scattering provides an unambiguous way for determining the temporal evolution of electron density during the first 100-microsec period.

  8. Simple Cloud Chambers Using Gel Ice Packs

    ERIC Educational Resources Information Center

    Kamata, Masahiro; Kubota, Miki

    2012-01-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

  9. Uniform-Temperature Walls for Cloud Chambers

    NASA Technical Reports Server (NTRS)

    Fleischman, G.

    1985-01-01

    Flat heat pipes rapidly transfer heat to and from experimental volumes. Heat pipe vapor chamber carries heat to and from thermo electric modules. Critical surface acts as evaporator or condenser in cloud physics experiments. Used as walls of spaceborne atmospheric cloud chambers. On Earth, used as isothermal floors for environmental test chambers.

  10. EPA GAS PHASE CHEMISTRY CHAMBER STUDIES

    EPA Science Inventory

    Gas-phase smog chamber experiments are being performed at EPA in order to evaluate a number of current chemical mechanisms for inclusion in EPA regulatory and research models. The smog chambers are 9000 L in volume and constructed of 2-mil teflon film. One of the chambers is co...

  11. Thermocapillary Motion in an Emulsion

    NASA Technical Reports Server (NTRS)

    Pukhnachov, Vladislav V.; Voinov, Oleg V.

    1996-01-01

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

  12. Characterization of flaxseed oil emulsions.

    PubMed

    Lee, Pei-En; Choo, Wee-Sim

    2015-07-01

    The emulsifying capacity of surfactants (polysorbate 20, polysorbate 80 and soy lecithin) and proteins (soy protein isolate and whey protein isolate) in flaxseed oil was measured based on 1 % (w/w) of emulsifier. Surfactants showed significantly higher emulsifying capacity compared to the proteins (soy protein isolate and whey protein isolate) in flaxseed oil. The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a mixer was ranked in the following order: 1,000 rpm (58 min) ≈ 1,000 rpm (29 min) ≈ 2,000 rpm (35 min) >2,000 rpm (17.5 min). The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a homogenizer (Ultra Turrax) was independent of the speed and mixing time. The mean particle size of the flaxseed oil emulsions prepared using the two mixing devices ranged from 23.99 ± 1.34 μm to 47.22 ± 1.99 μm where else the particle size distribution and microstructure of the flaxseed oil emulsions demonstrated using microscopic imaging were quite similar. The flaxseed oil emulsions had a similar apparent viscosity and exhibited shear thinning (pseudoplastic) behavior. The flaxseed oil emulsions had L* value above 70 and was in the red-yellow color region (positive a* and b* values). PMID:26139903

  13. 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.

  14. A cosmic ray super high multicore family event. 1: Experiment and general features

    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

    Information on the fragmentation region in super high energy hadronic interactions can be obtained through the observations of gamma-ray families produced by cosmic rays. Gamma-ray families with the sum of E sub gamma or 1000 TeV are receiving increasing interests in emulsion chamber experiments. There exist some complications caused by the superposition of nuclear and electromagnetic cascades and the uncertainty in the nature of the primary particles. These complications usually make the conclusions drawn from various interesting phenomena observed in family events not so definite. An interesting family event KO E19, which is likely to have suffered only very slight disturbances is described. It was found in the Mt. Kambala emulsion chamber experiment. The production height of the event is determined to be H=(70 + or - 30)m and some conclusions are given.

  15. Pine bark as bio-adsorbent for Cd, Cu, Ni, Pb and Zn: batch-type and stirred flow chamber experiments.

    PubMed

    Cutillas-Barreiro, L; Ansias-Manso, L; Fernández-Calviño, D; Arias-Estévez, M; Nóvoa-Muñoz, J C; Fernández-Sanjurjo, M J; Álvarez-Rodríguez, E; Núñez-Delgado, A

    2014-11-01

    The objective of this work was to determine the retention of five metals on pine bark using stirred flow and batch-type experiments. Resulting from batch-type kinetic experiments, adsorption was rapid, with no significant differences for the various contact times. Adsorption was between 98 and 99% for Pb(2+), 83-84% for Cu(2+), 78-84% for Cd(2+), 77-83% for Zn(2+), and 70-75% for Ni(2+), and it was faster for low concentrations, with Pb suffering the highest retention, followed by Cu, Cd, Ni and Zn. The fitting to the Freundlich and Langmuir models was satisfactory. Desorption increased in parallel to the added concentrations, with Pb always showing the lowest levels. Stirred flow chamber experiments showed strong hysteresis for Pb and Cu, sorption being mostly irreversible. The differences affecting the studied heavy metals are mainly due to different affinity for the adsorption sites. Pine bark can be used to effectively remove Pb and Cu from polluted environments. PMID:24973614

  16. Chamber QoE: a multi-instrumental approach to explore affective aspects in relation to quality of experience

    NASA Astrophysics Data System (ADS)

    De Moor, Katrien; Mazza, Filippo; Hupont, Isabelle; Ríos Quintero, Miguel; Mäki, Toni; Varela, Martín.

    2014-02-01

    Evaluating (audio)visual quality and Quality of Experience (QoE) from the user's perspective, has become a key element in optimizing users' experiences and their quality. Traditionally, the focus lies on how multi-level quality features are perceived by a human user. The interest has however gradually expanded towards human cognitive, affective and behavioral processes that may impact on, be an element of, or be influenced by QoE, and which have been underinvestigated so far. In addition, there is a major discrepancy between the new, broadly supported and more holistic conceptualization of QoE proposed by Le Callet et al. (2012) and traditional, standardized QoE assessment. This paper explores ways to tackle this discrepancy by means of a multi-instrumental approach. More concretely, it presents results from a lab study on video quality (N=27), aimed at going beyond the dominant QoE assessment paradigm and at exploring affective aspects in relation to QoE and in relation to perceived overall quality. Four types of data were collected: `traditional' QoE self-report measures were complemented with `alternative', emotional state- and user engagement-related self-report measures to evaluate QoE. In addition, we collected EEG (physiological) data, gazetracking data and facial expressions (behavioral) data. The video samples used in test were longer in duration than is common in standard tests allowing us to study e.g. more realistic experience and deeper user engagement. Our findings support the claim that the traditional QoE measures need to be reconsidered and extended with additional, affective staterelated measures.

  17. The olive oil-based lipid clinoleic blocks leukocyte recruitment and improves survival during systemic inflammation: a comparative in vivo study of different parenteral lipid emulsions.

    PubMed

    Buschmann, Kirsten; Poeschl, Johannes; Braach, Natascha; Hudalla, Hannes; Kuss, Navina; Frommhold, David

    2015-01-01

    Although fish oil-based and olive oil-based lipid emulsions have been shown to exert anti-inflammatory functions, the immunomodulating properties of lipids are still controversial. Therefore, we investigated the anti-inflammatory effect of three different parenterally administered lipid emulsions in vivo: olive oil-based Clinoleic, fish oil-based Smoflipid, and soybean oil-based Lipofundin. We observed leukocyte recruitment in inflamed murine cremaster muscle using intravital microscopy and survival in a murine model of LPS-induced systemic inflammation and analyzed expression of leukocyte and endothelial adhesion molecules. Olive oil-based Clinoleic and fish oil-based Smoflipid profoundly inhibited leukocyte adhesion compared to Lipofundin during LPS-induced inflammation of the murine cremaster muscle. In the trauma model of cremaster muscle inflammation, Lipofundin was the only lipid emulsion that even augmented leukocyte adhesion. In contrast to Smoflipid and Lipofundin, Clinoleic effectively blocked leukocyte recruitment and increased survival during lethal endotoxemia. Flow chamber experiments and analysis of adhesion molecule expression suggest that both endothelial and leukocyte driven mechanisms might contribute to anti-inflammatory effects of Clinoleic. We conclude that the anti-inflammatory properties of Clinoleic are superior to those of Smoflipid and Lipofundin even during systemic inflammation. Thus, these results should stimulate further studies investigating parenteral lipids as an anti-inflammatory strategy in critically ill patients. PMID:25767334

  18. The Olive Oil-Based Lipid Clinoleic Blocks Leukocyte Recruitment and Improves Survival during Systemic Inflammation: A Comparative In Vivo Study of Different Parenteral Lipid Emulsions

    PubMed Central

    Buschmann, Kirsten; Poeschl, Johannes; Braach, Natascha; Kuss, Navina

    2015-01-01

    Although fish oil-based and olive oil-based lipid emulsions have been shown to exert anti-inflammatory functions, the immunomodulating properties of lipids are still controversial. Therefore, we investigated the anti-inflammatory effect of three different parenterally administered lipid emulsions in vivo: olive oil-based Clinoleic, fish oil-based Smoflipid, and soybean oil-based Lipofundin. We observed leukocyte recruitment in inflamed murine cremaster muscle using intravital microscopy and survival in a murine model of LPS-induced systemic inflammation and analyzed expression of leukocyte and endothelial adhesion molecules. Olive oil-based Clinoleic and fish oil-based Smoflipid profoundly inhibited leukocyte adhesion compared to Lipofundin during LPS-induced inflammation of the murine cremaster muscle. In the trauma model of cremaster muscle inflammation, Lipofundin was the only lipid emulsion that even augmented leukocyte adhesion. In contrast to Smoflipid and Lipofundin, Clinoleic effectively blocked leukocyte recruitment and increased survival during lethal endotoxemia. Flow chamber experiments and analysis of adhesion molecule expression suggest that both endothelial and leukocyte driven mechanisms might contribute to anti-inflammatory effects of Clinoleic. We conclude that the anti-inflammatory properties of Clinoleic are superior to those of Smoflipid and Lipofundin even during systemic inflammation. Thus, these results should stimulate further studies investigating parenteral lipids as an anti-inflammatory strategy in critically ill patients. PMID:25767334

  19. Large outdoor chamber experiments and computer simulations: (I) Secondary organic aerosol formation from the oxidation of a mixture of d-limonene and α-pinene

    NASA Astrophysics Data System (ADS)

    Li, Qianfeng; Hu, Di; Leungsakul, Sirakarn; Kamens, Richard M.

    This work merges kinetic models for α-pinene and d-limonene which were individually developed to predict secondary organic aerosol (SOA) formation from these compounds. Three major changes in the d-limonene and α-pinene combined mechanism were made. First, radical-radical reactions were integrated so that radicals formed from both individual mechanisms all reacted with each other. Second, all SOA model species from both compounds were used to calculate semi-volatile partitioning for new semi-volatiles formed in the gas phase. Third particle phase reactions for particle phase α-pinene and d-limonene aldehydes, carboxylic acids, etc. were integrated. Experiments with mixtures of α-pinene and d-limonene, nitric oxide (NO), nitrogen dioxide (NO 2), and diurnal natural sunlight were carried out in a dual 270 m 3 outdoor Teflon film chamber located in Pittsboro, NC. The model closely simulated the behavior and timing for α-pinene, d-limonene, NO, NO 2, O 3 and SOA. Model sensitivities were tested with respect to effects of d-limonene/α-pinene ratios, initial hydrocarbon to NO x (HC 0/NO x) ratios, temperature, and light intensity. The results showed that SOA yield ( YSOA) was very sensitive to initial d-limonene/α-pinene ratio and temperature. The model was also used to simulate remote atmospheric SOA conditions that hypothetically could result from diurnal emissions of α-pinene, d-limonene and NO x. We observed that the volatility of the simulated SOA material on the aging aerosol decreased with time, and this was consistent with chamber observations. Of additional importance was that our simulation did not show a loss of SOA during the daytime and this was consistent with observed measurements.

  20. Multiwire proportional chamber development

    NASA Technical Reports Server (NTRS)

    Doolittle, R. F.; Pollvogt, U.; Eskovitz, A. J.

    1973-01-01

    The development of large area multiwire proportional chambers, to be used as high resolution spatial detectors in cosmic ray experiments is described. A readout system was developed which uses a directly coupled, lumped element delay-line whose characteristics are independent of the MWPC design. A complete analysis of the delay-line and the readout electronic system shows that a spatial resolution of about 0.1 mm can be reached with the MWPC operating in the strictly proportional region. This was confirmed by measurements with a small MWPC and Fe-55 X-rays. A simplified analysis was carried out to estimate the theoretical limit of spatial resolution due to delta-rays, spread of the discharge along the anode wire, and inclined trajectories. To calculate the gas gain of MWPC's of different geometrical configurations a method was developed which is based on the knowledge of the first Townsend coefficient of the chamber gas.

  1. Understanding Isoprene Photo-oxidation from Continuous-Flow Chamber Experiments: Unexpectedly High SOA Yields and New Insights into Isoprene Oxidation Pathways

    NASA Astrophysics Data System (ADS)

    Liu, J.; D'Ambro, E.; Lee, B. H.; Zaveri, R. A.; Thornton, J. A.; Shilling, J.

    2014-12-01

    Secondary organic aerosol (SOA) accounts for a substantial fraction of tropospheric aerosol and has significant impacts on climate and human health. Results from the CARES (Carbonaceous Aerosol and Radiative Effects Study) field mission suggested that isoprene oxidation moderated by anthropogenic emissions plays a dominant role in SOA formation, but current literature isoprene yields and oxidation mechanisms are unable to explain the CARES observations. In this study, we conducted a series of continuous-flow chamber experiments to investigate the yield and chemical composition of SOA formed from isoprene photo-oxidation as a function of NOx concentration. Under low-NOx (< 1ppbv) conditions, we measure SOA mass yields that are significantly larger than previously reported, reaching up to 20%, and the yields are strongly dependent on H2O2 concentrations. The higher yields are likely a result of differences between batch mode and continuous-flow experiments and the photochemical fate of the ISOPOOH intermediate under the high HO2 conditions of the chamber experiments. Online analysis of the SOA using the University of Washington FIGAERO HR-ToF-CIMS instrument shows that a C5H12O6 compound can explain a significant fraction of the mass measured by the AMS. We tentatively identify this compound as a dihydroxy dihydroperoxide produced from the oxidation of ISOPOOH. To our knowledge, we believe this represents the most direct confirmation that such dihydroperoxides form during isoprene oxidation and contribute to SOA. A van Krevelen analysis of HR-AMS data is consistent with hydroperoxide species forming the majority of the SOA. As progressively more NO was added to the system, yields initially increase to a maximum at an NO:isoprene ratio of ~1, and then rapidly decrease, to 3.6% at an NO:isoprene ratio of 4. As NO concentrations increased, alkyl nitrates accounts for an increasing portion of the SOA mass, though hydroperoxides remain significant. These observations of

  2. Atmospheric interactions detected in both the upper and the lower chambers at Chacaltaya

    NASA Technical Reports Server (NTRS)

    Amato, N. M.; Arata, N.; Maldonado, R. H. C.

    1985-01-01

    The cosmic ray interactions in the energy region 10 to the 13th power to 10 to the 17th power eV were studied by emulsion chambers exposed at Chacaltaya, 5220 m above sea-level. The chambers have a two-storied structure, and the events observed in both chambers give important informations on these phenomena. The first Centauro event was detected as a small shower at the bottom of the upper chamber and as a big fraction of energy deposit in the lower chamber, which indicates a high contribution of hadronic showers. Results of the events with continuation in the rather low energy region are described.

  3. 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.

  4. 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.

  5. 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.

  6. Nonlinear Dynamic Characteristics of Oil-in-Water Emulsions

    NASA Astrophysics Data System (ADS)

    Yin, Zhaoqi; Han, Yunfeng; Ren, Yingyu; Yang, Qiuyi; Jin, Ningde

    2016-08-01

    In this article, the nonlinear dynamic characteristics of oil-in-water emulsions under the addition of surfactant were experimentally investigated. Firstly, based on the vertical upward oil-water two-phase flow experiment in 20 mm inner diameter (ID) testing pipe, dynamic response signals of oil-in-water emulsions were recorded using vertical multiple electrode array (VMEA) sensor. Afterwards, the recurrence plot (RP) algorithm and multi-scale weighted complexity entropy causality plane (MS-WCECP) were employed to analyse the nonlinear characteristics of the signals. The results show that the certainty is decreasing and the randomness is increasing with the increment of surfactant concentration. This article provides a novel method for revealing the nonlinear dynamic characteristics, complexity, and randomness of oil-in-water emulsions with experimental measurement signals.

  7. SU-E-T-448: On the Perturbation Factor P-cav of the Markus Parallel Plate Ion Chambers in Clinical Electron Beams, Monte Carlo Based Reintegration of An Historical Experiment

    SciTech Connect

    Voigts-Rhetz, P von; Zink, K

    2014-06-01

    Purpose: All present dosimetry protocols recommend well-guarded parallel-plate ion chambers for electron dosimetry. For the guard-less Markus chamber an energy dependent fluence perturbation correction pcav is given. This perturbation correction was experimentally determined by van der Plaetsen by comparison of the read-out of a Markus and a NACP chamber, which was assumed to be “perturbation-free”. Aim of the present study is a Monte Carlo based reiteration of this experiment. Methods: Detailed models of four parallel-plate chambers (Roos, Markus, NACP and Advanced Markus) were designed using the Monte Carlo code EGSnrc and placed in a water phantom. For all chambers the dose to the active volume filled with low density water was calculated for 13 clinical electron spectra (E{sub 0}=6-21 MeV) at the depth of maximum and at the reference depth under reference conditions. In all cases the chamber's reference point was positioned at the depth of measurement. Moreover, the dose to water DW was calculated in a small water voxel positioned at the same depth. Results: The calculated dose ratio D{sub NACP}/D{sub Markus}, which according to van der Plaetsen reflects the fluence perturbation correction of the Markus chamber, deviates less from unity than the values given by van der Plaetsen's but exhibits a similar energy dependence. The same holds for the dose ratios of the other well guarded chambers. But, in comparison to water, the Markus chamber reveals the smallest overall perturbation correction which is nearly energy independent at both investigated depths. Conclusion: The simulations principally confirm the energy dependence of the dose ratio D{sub NACP}/D{sub Markus} as published by van der Plaetsen. But, as shown by our simulations of the ratio D{sub W}/D{sub Markus}, the conclusion drawn in all dosimetry protocols is questionable: in contrast to all well-guarded chambers the guard-less Markus chamber reveals the smallest overall perturbation correction and

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

    SciTech Connect

    Zhang Ying; Jin Chao

    2011-01-15

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

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

    SciTech Connect

    Pal, R.

    1995-04-01

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

  10. Modeling of the centering force in a compound emulsion to make uniform plastic shells for laser fusion targets

    SciTech Connect

    Norimatsu, T.; Izawa, Y.; Mima, K.; Gresho, P.M.

    1999-03-01

    In laser fusion experiment, fuel capsules with high sphericity and high wall-thickness uniformity are often fabricated by the emulsion method. To understand the process of forming the uniform wall by the emulsion method and to further improve the thickness uniformity, the formulated a model to simulate the centering process of a water globule in a compound emulsion. The authors newly added a thermodynamic force to the centering force in addition to previous hydrodynamic forces. The results indicate that nonuniform emulsion turns to be uniform by repeating instantaneous deformations followed with continuous rotation around the horizontal axis.

  11. 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

  12. 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.

  13. Controlling molecular transport in minimal emulsions.

    PubMed

    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

  14. Comparison of OH concentration measurements by DOAS and LIF during SAPHIR chamber experiments at high OH reactivity and low NO concentration

    NASA Astrophysics Data System (ADS)

    Fuchs, H.; Dorn, H.-P.; Bachner, M.; Bohn, B.; Brauers, T.; Gomm, S.; Hofzumahaus, A.; Holland, F.; Nehr, S.; Rohrer, F.; Tillmann, R.; Wahner, A.

    2012-07-01

    During recent field campaigns, hydroxyl radical (OH) concentrations that were measured by laser-induced fluorescence (LIF) were up to a factor of ten larger than predicted by current chemical models for conditions of high OH reactivity and low NO concentration. These discrepancies, which were observed in forests and urban-influenced rural environments, are so far not entirely understood. In summer 2011, a series of experiments was carried out in the atmosphere simulation chamber SAPHIR in Jülich, Germany, in order to investigate the photochemical degradation of isoprene, methyl-vinyl ketone (MVK), methacrolein (MACR) and aromatic compounds by OH. Conditions were similar to those experienced during the PRIDE-PRD2006 campaign in the Pearl River Delta (PRD), China, in 2006, where a large difference between OH measurements and model predictions was found. During experiments in SAPHIR, OH was simultaneously detected by two independent instruments: LIF and differential optical absorption spectroscopy (DOAS). Because DOAS is an inherently calibration-free technique, DOAS measurements are regarded as a reference standard. The comparison of the two techniques was used to investigate potential artifacts in the LIF measurements for PRD-like conditions of OH reactivities of 10 to 30 s-1 and NO mixing ratios of 0.1 to 0.3 ppbv. The analysis of twenty experiment days shows good agreement. The linear regression of the combined data set (averaged to the DOAS time resolution, 2495 data points) yields a slope of 1.02 ± 0.01 with an intercept of (0.10 ± 0.03) × 106 cm-3 and a linear correlation coefficient of R2 = 0.86. This indicates that the sensitivity of the LIF instrument is well-defined by its calibration procedure. No hints for artifacts are observed for isoprene, MACR, and different aromatic compounds. LIF measurements were approximately 30-40% (median) larger than those by DOAS after MVK (20 ppbv) and toluene (90 ppbv) had been added. However, this discrepancy has a

  15. Comparison of OH concentration measurements by DOAS and LIF during SAPHIR chamber experiments at high OH reactivity and low NO concentration

    NASA Astrophysics Data System (ADS)

    Fuchs, H.; Dorn, H.-P.; Bachner, M.; Bohn, B.; Brauers, T.; Gomm, S.; Hofzumahaus, A.; Holland, F.; Nehr, S.; Rohrer, F.; Tillmann, R.; Wahner, A.

    2012-03-01

    During recent field campaigns, hydroxyl radical (OH) concentrations that were measured by laser-induced fluorescence (LIF) were up to a factor of ten larger than predicted by current chemical models for conditions of high OH reactivity and low NO concentration. These discrepancies, which were observed in forests and urban-influenced rural environments, are so far not entirely understood. In summer 2011, a series of experiments was carried out in the atmosphere simulation chamber SAPHIR in Jülich, Germany, in order to investigate the photochemical degradation of isoprene, methyl-vinyl ketone (MVK), methacrolein (MACR) and aromatic compounds by OH. Conditions were similar to those experienced during the PRIDE-PRD2006 campaign in the Pearl River Delta (PRD), China, in 2006, where a large difference between OH measurements and model predictions was found. During experiments in SAPHIR, OH was simultaneously detected by two independent instruments: LIF and differential optical absorption spectroscopy (DOAS). Because DOAS is an inherently calibration-free technique, DOAS measurements are regarded as a reference standard. The comparison of the two techniques was used to investigate potential artifacts in the LIF measurements for PRD-like conditions of OH reactivities of 10 to 30 s-1 and NO mixing ratios of 0.1 to 0.3 ppbv. The analysis of twenty experiment days shows good agreement. The linear regression of the combined data set (averaged to the DOAS time resolution, 2495 data points) yields a slope of 1.02 ± 0.01 with an intercept of (0.10 ± 0.03) ×106 cm-3 and a linear correlation coefficient of R2=0.86. This indicates that the sensitivity of the LIF instrument is well-defined by its calibration procedure. No hints for artifacts are observed for isoprene, MACR, and different aromatic compounds. LIF measurements were approximately 30-40% (median) larger than those by DOAS after MVK and toluene had been added. However, this discrepancy has a large uncertainty and

  16. 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.

  17. An anxiety, personality and altitude symptomatology study during a 31-day period of hypoxia in a hypobaric chamber (experiment 'Everest-Comex 1997').

    PubMed

    Nicolas, M; Thullier-Lestienne, F; Bouquet, C; Gardette, B; Gortan, C; Joulia, F; Bonnon, M; Richalet, J P; Therme, P; Abraini, J H

    1999-12-01

    Extreme environmental situations are useful tools for the investigation of the general processes of adaptation. Among such situations, high altitude of more than 3000 m produces a set of pathological disorders that includes both cerebral (cAS) and respiratory (RAS) altitude symptoms. High altitude exposure further induces anxiety responses and behavioural disturbances. The authors report an investigation on anxiety responses, personality traits, and altitude symptoms (AS) in climbers participating in a 31-day period of confinement and gradual decompression in a hypobaric chamber equivalent to a climb from sea-level to Mount Everest (8848 m altitude). Personality traits, state-trait anxiety, and AS were assessed, using the Cattell 16 Personality Factor questionnaire (16PF), the Spielberger's State-Trait Anxiety Inventory (STAI), and the Lake Louise concensus questionnaire. Results show significant group effect for state-anxiety and AS; state-anxiety and AS increased as altitude increased. They also show that state-type anxiety shows a similar time-course to cAS, but not RAS. Alternatively, our results demonstrate a significant negative correlation between Factor M of the 16PF questionnaire, which is a personality trait that ranges from praxernia to autia. In contrast, no significant correlation was found between personality traits and AS. This suggests that AS could not be predicted using personality traits and further support that personality traits, such as praxernia (happening sensitivity), could play a major role in the occurrence of state-type anxiety responses in extreme environments. In addition, the general processes of coping and adaptation in individuals participating in extreme environmental experiments are discussed. PMID:11543191

  18. Field studies of BrO and IO at salt ponds (Namibia and Botswana) and related smog chamber experiments on environmental salt and soil samples

    NASA Astrophysics Data System (ADS)

    Buxmann, Joelle; Balzer, Natalja; Bleicher, Sergej; Kotte, Karsten; Platt, Ulrich; Zetzsch, Cornelius; Pienaar, Jacobus J.

    2010-05-01

    Previous studies have shown that salt lakes provide a significant source for gaseous reactive halogen compounds. Reactive halogen species (RHS) influence the ozone chemistry. Iodine chemistry is known to initiate particle formation, where the relevant nucleation mechanism is not fully understood. The RHS IO and BrO were investigated by Multi- Axis- Differential- Optical- Absorption- Spectroscopy (MAX-DOAS) of scattered sunlight at two different salt ponds. At a coastal salt evaporation pond for production of sodium chloride in Namibia (Walfish Bay) as well as at a natural salt pond in Botswana (Sua Pan) a tropospheric IO signal was observed. In Namibia the slant column density (SCD) rose up to (4.5±0.7) ×1013 molec/cm2 (elevation angle: 5° ). Assuming a typical layer thickness of 500 m, this would correspond to a concentration of (3.3±0.5) ppt. The mean SCD of IO was (2.2±0.5) ×1013 molec/cm2at Sua Pan for 5° elevation angle. At both measurement sites tropospheric BrO remained below the detection limit of 1.8 × 1013molec/cm2or 1.3ppt, respectively. Many aspects of the underlying mechanisms for the release of reactive halogen compounds, their sources and sinks are not well understood yet. In order to investigate the release of RHS soil and salt samples from both measurement sites are exposed to simulated sunlight in a teflon smog-chamber experiment at Bayreuth. RHS are observed by DOAS with a multireflection system. An ozone analyzer, a gas chromátograph (with flame ionisation detector) and a scanning electrostatical classifier with condensation nuclei counter are employed for monitoring hydrocarbons and aerosol, respectively.

  19. 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

  20. 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.

  1. Experimental investigation of a lightweight rocket chamber

    NASA Technical Reports Server (NTRS)

    Dalgleish, John E; Tischler, Adelbert O

    1953-01-01

    Experiments have been conducted with a jacketed rocket combustion chamber that was fabricated by hydraulic-forming from sheet metal. Rocket combustion chambers made by this method have been used successfully. Runs with these combustion chambers have been made at over-all heat-transfer rates 1.7 Btu per square inch per second with water cooling and also ammonia as a regenerative coolant.

  2. 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.

  3. Steroidal Compounds in Commercial Parenteral Lipid Emulsions

    PubMed Central

    Xu, Zhidong; Harvey, Kevin A.; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P.; Siddiqui, Rafat A.

    2012-01-01

    Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction. PMID:23016123

  4. 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.

  5. 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.

  6. Study of Double-strangeness Nuclear Systems with Nuclear Emulsion

    NASA Astrophysics Data System (ADS)

    Nakazawa, Kazuma; Endo, Yoko; Hoshino, Kaoru; Ito, Hiroki; Kinbara, Shinji; Kobayashi, Hidetaka; Mishina, Akihiro; Soe, Myint Kyaw; Theint, Aye Moh Moh; Xu, Rong; Tint, Khin Than; Yoshida, Jun'ya; Zhang, Dong Hai

    Double strangeness nuclei such as double-Λ and Ξ hypernuclei have been studied with nuclear emulsion due to its fine position resolution. Recently, we have started an experiment to study Λ-Λ interaction more accurately than that information given by the NAGARA event with ∼102 double-Λ hypernuclei which may provide us understanding free from nuclear medium effect. It is necessary to develop treatment method for huge amount, 2.1 tons of the emulsion gel, even if very pure K- beams are available at J-PARC. We have developed the base film to support the emulsion, emulsion surface coating method with a special layer of 0.5 μm thick, method for making large-size plate (35.0 x 34.5 cm2) and scanning method, called "overall scanning". The first evidence of a deeply bound state of Ξ--14N system, named KISO, was successfully detected in the test operation of the overall scanning.

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

    PubMed

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

    2012-09-01

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

  8. Changing Emulsion Dynamics with Heterogeneous Surface Wettability

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    We elucidate the effect of heterogeneous surface wettability on the morphology and dynamics of microfluidic emulsions, generated by a co-flowing device. We first design a useful methodology of modifying a micro-capillary with desired heterogeneous wettability, such as alternating hydrophilic and hydrophobic regions. Subsequently, the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion in the micro-capillary are investigated. Our experimental data reveal a universal critical time scale of advective emulsions, above which the microfluidic emulsions remain intact, whereas below this time-scale emulsions become adhesive or inverse. A simple model based on a force balance can be used to explain this critical transition. These results show a control of emulsion dynamics by tuning the droplet size and the Capillary number, the ratio of viscous to surface effects, with heterogeneous surface wettability.

  9. Intravenous Lipid Emulsions in Parenteral Nutrition.

    PubMed

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

    2015-09-01

    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

  10. Two chamber reaction furnace

    DOEpatents

    Blaugher, R.D.

    1998-05-05

    A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  11. Two chamber reaction furnace

    DOEpatents

    Blaugher, Richard D.

    1998-05-05

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  12. Laboratory Course on Drift Chambers

    NASA Astrophysics Data System (ADS)

    García-Ferreira, Ix-B.; García-Herrera, J.; Villaseñor, L.

    2006-09-01

    Drift chambers play an important role in particle physics experiments as tracking detectors. We started this laboratory course with a brief review of the theoretical background and then moved on to the the experimental setup which consisted of a single-sided, single-cell drift chamber. We also used a plastic scintillator paddle, standard P-10 gas mixture (90% Ar, 10% CH4) and a collimated 90Sr source. During the laboratory session the students performend measurements of the following quantities: a) drift velocities and their variations as function of the drift field; b) gas gains and c) diffusion of electrons as they drifted in the gas.

  13. 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. PMID:27021875

  14. 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. PMID:26603612

  15. Creating Chamber Music Enthusiasts in High School.

    ERIC Educational Resources Information Center

    Cummiskey, Cynthia

    1999-01-01

    Describes the Fairfield High School Chamber Music Honors Program for students in grades nine through twelve in Fairfield (Connecticut). Explains that the program's goal is to provide students with a positive experience in chamber music. Highlights the creation and the first two years of the program. (CMK)

  16. Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments

    NASA Astrophysics Data System (ADS)

    Chirico, R.; Decarlo, P. F.; Heringa, M. F.; Tritscher, T.; Richter, R.; Prevot, A. S. H.; Dommen, J.; Weingartner, E.; Wehrle, G.; Gysel, M.; Laborde, M.; Baltensperger, U.

    2010-06-01

    Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the final vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC<0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23-0.56 g/kg fuel burned. In presence of both a DOC and a DPF, primary particles with a mobility diameter above 5 nm were 300±19 cm-3, and only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.097 to 0

  17. Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments

    NASA Astrophysics Data System (ADS)

    Chirico, R.; Decarlo, P. F.; Heringa, M. F.; Tritscher, T.; Richter, R.; Prévôt, A. S. H.; Dommen, J.; Weingartner, E.; Wehrle, G.; Gysel, M.; Laborde, M.; Baltensperger, U.

    2010-12-01

    Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the third vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC < 0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23-0.56 g/kg fuel burned. In presence of both a DOC and a DPF, only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.10 to 0.19. Five hours of oxidation led to a more oxidized OA with an O/C range of 0

  18. Spreading of Emulsions on Glass Substrates

    NASA Astrophysics Data System (ADS)

    Mohammad Karim, Alireza; Kavehpour, Pirouz

    2012-11-01

    The wettability of emulsions is an important factor with explicit influence in an extensive variety of industrial applications ranging from the petroleum to food industries. Surprisingly, there is no comprehensive study of emulsion spreading to date; this is due to the complexity of the structure of the emulsions and non-homogeneity of the dispersed phase bubbles in size as well as distribution through the emulsion. The spreading of water/silicone oil emulsions on glass substrates was investigated. The emulsions were prepared with varying volume fractions of water dispersed in silicone oil, with addition of small amounts of surfactant to stabilize the emulsion structure. The time dependent variation of dynamic contact angle, base diameter, and the spreading rate of the droplets of an emulsion are different from a pure substance. The effect of water/silicone oil weight percentage as well as the droplet size and dispersed phase bubble size were also investigated. The weight percentage of water/silicone oil emulsion and droplet size did not have significant influence on the spreading dynamics; however the dispersed phase drop size affected the spreading dynamics substantially.

  19. Altering Emulsion Stability with Heterogeneous Surface Wettability.

    PubMed

    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

  20. Deactivation efficiency of stabilized bactericidal emulsions.

    PubMed

    Vyhnalkova, Renata; Eisenberg, Adi; van de Ven, Theo G M

    2011-09-20

    Biocide emulsions stabilized with various stabilizing agents were prepared and characterized, and their efficiency in bacteria deactivation was evaluated. A number of stabilizing agents were tested for their stabilizing effect on emulsions of thiocyanomethylthiobenzothiazole (TCMTB) biocide. Two agents, the most successful in stabilizing the biocide, were chosen for further studies: high molecular weight polyethyleneimine (PEI) and an amphiphilic block copolymer of poly(caprolactone)-b-poly(acrylic acid) (PCL(33)-b-PAA(33)). The emulsion droplet sizes varied between 325 and 500 nm. Deactivation of bacteria was studied by exposing E. coli ATCC 11229 bacteria dispersions to emulsions stabilized by positively charged PEI or negatively charged PCL-b-PAA micelles and by measuring their absorbance; E. coli do not grow with time in the presence of biocide emulsions. PEI molecules alone act as biocide and deactivate the bacteria. PCL-b-PAA micelles as stabilizing agent do not affect the growth of the E. coli ; bacteria are deactivated by TCMTB released from the emulsion droplets. The kinetics of emulsion dissolution studies revealed for both stabilizing agents a decrease in droplet size with time while the emulsions were subjected to dialysis. The biocide was released from the emulsions within ∼250 min; the droplet shells consist mostly of PEI or PCL-b-PAA insoluble complexes with the biocide, which do not dissolve during dialysis. SEM images confirm the presence of residual crumbled shells with holes after 24 h of dialysis. PMID:21823610

  1. Neutron Detection via Bubble Chambers

    SciTech Connect

    Jordan, David V.; Ely, James H.; Peurrung, Anthony J.; Bond, Leonard J.; Collar, J. I.; Flake, Matthew; Knopf, Michael A.; Pitts, W. K.; Shaver, Mark W.; Sonnenschein, Andrew; Smart, John E.; Todd, Lindsay C.

    2005-10-06

    The results of a Pacific Northwest National Laboratory (PNNL) exploratory research project investigating the feasibility of fast neutron detection using a suitably prepared and operated, pressure-cycled bubble chamber are described. The research was conducted along two parallel paths. Experiments with a slow pressure-release Halon chamber at the Enrico Fermi Institute at the University of Chicago showed clear bubble nucleation sensitivity to an AmBe neutron source and insensitivity to the 662 keV gammas from a 137Cs source. Bubble formation was documented via high-speed (1000 frames/sec) photography, and the acoustic signature of bubble formation was detected using a piezo-electric transducer element mounted on the base of the chamber. The chamber’s neutron sensitivity as a function of working fluid temperature was mapped out. The second research path consisted of the design, fabrication, and testing of a fast pressure-release Freon-134a chamber at PNNL. The project concluded with successful demonstrations of the PNNL chamber’s AmBe neutron source sensitivity and 137Cs gamma insensitivity. The source response tests of the PNNL chamber were documented with high-speed photography.

  2. Measuring the Free Fall of Antihydrogen with Emulsion Detectors

    NASA Astrophysics Data System (ADS)

    Pistillo, C.

    2014-06-01

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

  3. Experimental observation of local rearrangements in dense quasi-two-dimensional emulsion flow.

    PubMed

    Chen, Dandan; Desmond, Kenneth W; Weeks, Eric R

    2015-06-01

    We experimentally study rearranging regions in slow athermal flow by observing the flow of a concentrated oil-in-water emulsion in a thin chamber with a constricting hopper shape. The gap of the chamber is smaller than the droplet diameters, so that the droplets are compressed into quasi-two-dimensional pancakes. We focus on localized rearrangements known as "T1 events" where four droplets exchange neighbors. Flowing droplets are deformed due to forces from neighboring droplets, and these deformations are decreased by nearby T1 events, with a spatial dependence related to the local structure. We see a tendency of the T1 events to occur in small clusters. PMID:26172718

  4. Observations of vaporizing water-in-fuel emulsion droplets

    SciTech Connect

    Sheffield, S.A.; Baer, M.R.; Denison, G.J.

    1980-01-01

    These observations in a Leidenfrost-type experiment allowed one to distinguish between different mechanisms in the emulsion combustion process. Three events were observed: disruptions, heterogeneously nucleated vapor explosions, and homogeneously nucleated vapor explosions. The last event greatly enhances combustion. The cenospheres, carbospheres or oil-coke particles formed will be reduced or eliminated by the vapor explosions, and any small solid fragments are likely to be consumed in the enhanced combustion processes. (DLC)

  5. Gas gain operations with single photon resolution using an integrating ionization chamber in small-angle X-ray scattering experiments

    NASA Astrophysics Data System (ADS)

    Menk, R. H.; Sarvestani, A.; Besch, H. J.; Walenta, A. H.; Amenitsch, H.; Bernstorff, S.

    2000-01-01

    In this work a combination of an ionization chamber with one-dimensional spatial resolution and a MicroCAT structure will be presented. Initially, MicroCAT was thought of as a shielding grid (Frisch-grid) but later was used as an active electron amplification device that enables single X-ray photon resolution measurements at low fluxes even with integrating readout electronics. Moreover, the adjustable gas gain that continuously covers the entire range from pure ionization chamber mode up to high gas gains (30 000 and more) provides stable operation yielding a huge dynamic range of about 10 8 and more. First measurements on biological samples using small angle X-ray scattering techniques with synchrotron radiation will be presented.

  6. Oxygen isotope ratios (18O/16O) of hemicellulose-derived sugar biomarkers in plants, soils and sediments as paleoclimate proxy I: Insight from a climate chamber experiment

    NASA Astrophysics Data System (ADS)

    Zech, Michael; Mayr, Christoph; Tuthorn, Mario; Leiber-Sauheitl, Katharina; Glaser, Bruno

    2014-02-01

    The oxygen isotopic composition of cellulose is a valuable proxy in paleoclimate research. However, its application to sedimentary archives is challenging due to extraction and purification of cellulose. Here we present compound-specific δ18O results of hemicellulose-derived sugar biomarkers determined using gas chromatography-pyrolysis-isotope ratio mass spectrometry, which is a method that overcomes the above-mentioned analytical challenges. The biomarkers were extracted from stem material of different plants (Eucalyptus globulus, Vicia faba and Brassica oleracea) grown in climate chamber experiments under different climatic conditions. The δ18O values of arabinose and xylose range from 31.4‰ to 45.9‰ and from 28.7‰ to 40.8‰, respectively, and correlate highly significantly with each other (R = 0.91, p < 0.001). Furthermore, δ18Ohemicellulose (mean of arabinose and xylose) correlate highly significantly with δ18Oleaf water (R = 0.66, p < 0.001) and significantly with modeled δ18Ocellulose (R = 0.42, p < 0.038), as well as with relative air humidity (R = -0.79, p < 0.001) and temperature (R = -0.66, p < 0.001). These findings confirm that the hemicellulose-derived sugar biomarkers, like cellulose, reflect the oxygen isotopic composition of plant source water altered by climatically controlled evapotranspirative 18O enrichment of leaf water. While relative air humidity controls most rigorously the evapotranspirative 18O enrichment, the direct temperature effect is less important. However, temperature can indirectly exert influence via plant physiological reactions, namely by influencing the transpiration rate which affects δ18Oleaf water due to the Péclet effect. In a companion paper (Tuthorn et al., this issue) we demonstrate the applicability of the hemicellulose-derived sugar biomarker δ18O method to soils and provide evidence from a climate transect study confirming that relative air humidity exerts the dominant control on evapotranspirative 18O

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. Dynamic modeling of emulsion polymerization reactors

    SciTech Connect

    Penlidis, A.; Hamielec, A.E.; MacGregor, J.F.

    1985-06-01

    This paper is a survey of recent published works on the dynamic and steady state modeling of emulsion homo- and copolymerization in batch, semicontinuous , and continuous latex reactors. Contributions to our understanding of diffusion-controlled termination and propagation reactions, molecular weight, long chain branching and crosslinking development, polymer particle nucleation, and of the dynamics of continuous emulsion polymerization are critically reviewed.

  12. 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.

  13. Suppression of Ostwald ripening in active emulsions.

    PubMed

    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. PMID:26274171

  14. 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.

  15. Treatment of oil-in-water emulsions

    SciTech Connect

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

    1980-01-08

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

  16. Treatment of oil-in-water emulsions

    SciTech Connect

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

    1980-01-08

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

  17. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sargusingh, Miriam M.

    2011-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications, including the treatment of medical conditions. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy available in the developing world for the treatment of a variety of medical conditions. Specifically, hyperbaric oxygen therapy is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. Hyperbaric oxygen therapy is simply too expensive and too dangerous to implement in the developing world using standard equipment. The hydrostatic hyperbaric chamber technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system that will provide controlled pressurization of the system, and provide adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the

  18. Unifying the relative hindered velocity in suspensions and emulsions of nondeformable particles

    NASA Astrophysics Data System (ADS)

    Faroughi, Salah Aldin; Huber, Christian

    2015-01-01

    Although the relative velocity of a single crystal or bubble in a quiescent fluid (melt) is well characterized, the interplay of crystals/bubbles in multiparticle systems and its effect on their settling/rising velocity is poorly quantified. We propose a theoretical model for the hindered velocity of non-Brownian emulsions and suspensions of nondeformable fluid and solid particles in the creeping flow regime. The model is based on three sets of correction: two on the drag coefficient experienced by each particle to account for both return flow and Smoluchowski effects and a correction on the rheology to account for nonlocal interactions introduced as a mean-field effective viscosity. Our model is tested against new and published experimental data over a wide range of particle volume fraction and viscosity ratio between the fluids. We find an excellent agreement between our model and experiments. The model is then applied to show that hindered settling can increase mineral residence time by up to an order of magnitude in convecting magma chambers.

  19. 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

  20. New cloud chamber experiments on the heterogeneous ice nucleation ability of oxalic acid in the deposition nucleation and immersion freezing modes

    NASA Astrophysics Data System (ADS)

    Moehler, O.; Wagner, R.; Saathoff, H.; Schnaiter, M.; Leisner, T.

    2010-12-01

    Dicarboxylic acids are ubiquitous components of the water-soluble organic fraction of the tropospheric aerosol. Their contribution to the total particulate organic carbon typically ranges from 1 - 3 wt% in urban and semi-urban areas to up to 10 wt% in remote marine atmospheres [1,2]. Oxalic acid, malonic acid, and succinic acid are usually the most abundant species, partly comprising more than 80% of the total diacid mass concentrations [3]. Several recent studies have addressed the ice nucleation potential of solid low-molecular weight dicarboxylic acids. On the one hand, the dicarboxylic acids can act as deposition mode ice nuclei provided that they are directly exposed to an ice supersaturated environment, e.g. in form of a coating layer that was formed by physical and chemical processing on prevalent particulates such as mineral dust and soot. At typical tropospheric relative humidities, diacids of low water solubility like oxalic and succinic acid may, on the other hand, also be present as solids that are immersed in aqueous inorganic and/or organic solution droplets [4,5]. These embedded crystals can act as ice nuclei in the immersion mode. Here we present new results from recent experiments at the aerosol and cloud chamber facility of the Karlsruhe Institute of Technology. The ice nucleation ability of aqueous and crystalline oxalic acid aerosol particles was investigated at expansion cooling conditions in the temperature range between 244 and 228 K [6]. Oxalic acid dihydrate particles with diameters between 0.03 to 0.8 μm, that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets, showed a high deposition mode ice activity at temperatures around 244 K. The ice onset humidity was below 110 % with respect to ice, and the ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles

  1. 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.

  2. Cocoa particles for food emulsion stabilisation.

    PubMed

    Gould, Joanne; Vieira, Josélio; Wolf, Bettina

    2013-09-01

    Emulsifying properties of cocoa particles have been investigated in systems containing purified sunflower oil (PSO) and water at varying pH, concentration and source of cocoa particles including cocoa powders (CP), cocoa fibre (CF) and cocoa mass (CM). The effect of cocoa particle source, pH and cocoa particle concentration on emulsion stability was evaluated by following changes in characteristic droplet diameter. Size distributions acquired on the emulsions and aqueous cocoa particle suspensions overlapped. Based on cryo-SEM imaging of the emulsions, isolation of cocoa particle fines and a process of washing the cocoa particles to remove any water soluble molecules, it was concluded that the cocoa particle fines not captured by the small angle laser diffraction method employed for sizing, act as Pickering particles. This research has demonstrated a universal nature of a natural food particle to stabilise oil-in-water emulsions not requiring particle modification or adjusting of the solution properties of the emulsion phases. PMID:23851644

  3. Non-aqueous Isorefractive Pickering Emulsions.

    PubMed

    Thompson, Kate L; Lane, Jacob A; Derry, Matthew J; Armes, Steven P

    2015-04-21

    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

  4. 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

  5. Spectra, composition and interactions of nuclei above 10 TeV using magnet-interferometric chambers (SCIN/MAGIC)

    NASA Technical Reports Server (NTRS)

    Wefel, John P.

    1991-01-01

    Initial definition studies were performed for the SCIN/MAGIC experiment selected as an Astromag investigation on Space Station Freedom. The study focused on Science Objectives and Science Requirement, Accommodation on both the STS and the Astromag facility, Data extraction techniques and Background Studies. The detectors are emulsion chambers which will be exposed for approximately 90 days and then recovered from orbit for subsequent processing and analysis in the laboratory. Such a technique is the only means to obtain information on the ultrahigh energy cosmic rays and their nuclear interactions. The SCIN/MAGIC investigation can supply unique data in relatively unexplored energy region and address many of the fundamental questions in particle astrophysics.

  6. Emulsion-based encapsulation and delivery of nanoparticles for the controlled release of alkalinity within the subsurface environment

    NASA Astrophysics Data System (ADS)

    Ramsburg, C. A.; Muller, K.; Gill, J.

    2012-12-01

    Many current approaches to managing groundwater contamination rely on further advances in amendment delivery in order to initiate and sustain contaminant degradation or immobilization. In fact, limited or ineffective delivery is often cited when treatment objectives are not attained. Emulsions, specifically oil-in-water emulsions, have demonstrated potential to aid delivery of remediation amendments. Emulsions also afford opportunities to control the release of active ingredients encapsulated within the droplets. Our research is currently focused on the controlled release of nanoparticle-based buffering agents using oil-in-water emulsions. This interest is motivated by the fact that chemical and biological processes employed for the remediation and stewardship of contaminated sites often necessitate control of pH during treatment and, in some cases, long thereafter. Alkalinity-release nanoparticles (e.g., CaCO3, MgO) were suspended within soybean oil and subsequently encapsulated by through the creation of oil-in-water emulsions. These oil-in-water emulsions are designed to have physical properties which are favorable for subsurface delivery (nominal properties: 1 g/mL density; 10 cP viscosity; and 1.5 μm droplet diameter). Buffer capacity titrations suggest that MgO particles are moderately more accessible within the oil phase and nearly twice as effective (on a per mass basis) at releasing alkalinity (as compared to the CaCO3 particles). Results from experiments designed to assess the release kinetics suggest that a linear driving force model is capable of describing the release process and mass transfer coefficients are constant through the reactive life of the emulsion. The release kinetics in emulsions containing MgO particles were found to be three orders of magnitude faster than those quantified for emulsions containing CaCO3. The slower release kinetics of the emulsions containing CaCO3 particles may prove beneficial when considering pH control at sites

  7. Emulsion ripening through molecular exchange at droplet contacts.

    PubMed

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

    2015-01-26

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

  8. 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.

  9. Rearrangements during slow compression of a jammed 2D emulsion

    NASA Astrophysics Data System (ADS)

    Du, Xin; Orellana, Carlos; Hong, Xia; Weeks, Eric

    We experimentally study non-affine motion within an evaporating 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. In this system, water slowly evaporates from an open edge of the chamber and, as a consequence, the volume fraction of oil droplets gradually increases. By means of microscopy, we analyzed the motion of droplets and measure the deformation of the droplet's outlines. Based on this information, we calculate the force network and the Voronoi cell when the system approaching jamming state. Using a recently proposed method (J. Rieser et al., arXiv:1509.05496), we calculate the Voronoi cell anisotropy vectors which point from the center of each particle to the corresponding Voronoi cell centroid, and identify void spaces where droplets may be more likely to move toward according to the field of the vectors. These allow us to study the correlations between the force network, the Voronoi vector field, and the non-affine displacements of droplets in our evaporating system.

  10. MPS II drift chamber system

    SciTech Connect

    Platner, E.D.

    1982-01-01

    The MPS II detectors are narrow drift space chambers designed for high position resolution in a magnetic field and in a very high particle flux environment. Central to this implementation was the development of 3 multi-channel custom IC's and one multi-channel hybrid. The system is deadtimeless and requires no corrections on an anode-to-anode basis. Operational experience and relevance to ISABELLE detectors is discussed.

  11. The crop growth research chamber

    NASA Technical Reports Server (NTRS)

    Wagenbach, Kimberly

    1993-01-01

    The Crop Growth Research Chamber (CGRC) has been defined by CELSS principle investigators and science advisory panels as a necessary ground-based tool in the development of a regenerative life support system. The focus of CGRC research will be on the biomass production component of the CELSS system. The ground-based Crop Growth Research Chamber is for the study of plant growth and development under stringently controlled environments isolated from the external environment. The chamber has importance in three areas of CELSS activities: (1) crop research; (2) system control and integration, and (3) flight hardware design and experimentation. The laboratory size of the CGRC will be small enough to allow duplication of the unit, the conducting of controlled experiments, and replication of experiments, but large enough to provide information representative of larger plant communities. Experiments will focus on plant growth in a wide variety of environments and the effects of those environments on plant production of food, water, oxygen, toxins, and microbes. To study these effects in a closed system, tight control of the environment is necessary.

  12. The Mobile Chamber

    NASA Technical Reports Server (NTRS)

    Scharfstein, Gregory; Cox, Russell

    2012-01-01

    A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

  13. Target chambers for gammashpere

    SciTech Connect

    Carpenter, M.P.; Falout, J.W.; Nardi, B.G.

    1995-08-01

    One of our responsibilities for Gammasphere, was designing and constructing two target chambers and associated beamlines to be used with the spectrometer. The first chamber was used with the early implementation phase of Gammasphere, and consisted of two spun-Al hemispheres welded together giving a wall thickness of 0.063 inches and a diameter of 12 inches.

  14. Static diffusion cloud chambers

    NASA Technical Reports Server (NTRS)

    Ayers, G.

    1981-01-01

    The chamber geometry and optical arrangement are described. The supersaturation range is given and consists of readings taken at five fixed points: 0.25%, 0.5%, 0.75%, 1.0%, and 1.25%. The detection system is described including light source, cameras, and photocell detectors. The temperature control and the calibration of the chamber are discussed.

  15. High resolution drift chambers

    SciTech Connect

    Va'vra, J.

    1985-07-01

    High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

  16. 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

  17. Gas Electron Multiplier (GEM) Chamber Characteristics Test

    SciTech Connect

    Yu, Jaehoon; White, Andy; Park, Seongtae; Hahn, Changhie; Baldeloma, Edwin; Tran, Nam; McIntire, Austin; Soha, Aria; /Fermilab

    2011-01-11

    Gas Electron Multipliers (GEMs) have been used in many HEP experiments as tracking detectors. They are sensitive to X-rays which allows use beyond that of HEP. The UTA High Energy group has been working on using GEMs as the sensitive gap detector in a DHCAL for the ILC. The physics goals at the ILC put a stringent requirement on detector performance. Especially the precision required for jet mass and positions demands an unprecedented jet energy resolution to hadronic calorimeters. A solution to meet this requirement is using the Particle Flow Algorithm (PFA). In order for PFA to work well, high calorimeter granularity is necessary. Previous studies based on GEANT simulations using GEM DHCAL gave confidence on the performance of GEM in the sensitive gap in a sampling calorimeter and its use as a DHCAL in PFA. The UTA HEP team has built several GEM prototype chambers, including the current 30cm x 30cm chamber integrated with the SLAC-developed 64 channel kPiX analog readout chip. This chamber has been tested on the bench using radioactive sources and cosmic ray muons. In order to have fuller understanding of various chamber characteristics, the experiments plan to expose 1-3 GEM chambers of dimension 35cm x 35cm x 5cm with 1cm x 1cm pad granularity with 64 channel 2-D simultaneous readout using the kPiX chip. In this experiment the experiments pan to measure MiP signal height, chamber absolute efficiencies, chamber gain versus high voltage across the GEM gap, the uniformity of the chamber across the 8cm x 8cm area, cross talk and its distance dependence to the triggered pad, chamber rate capabilities, and the maximum pad occupancy rate.

  18. Aging in large CDF tracking chambers

    SciTech Connect

    M. Binkley et al.

    2001-03-19

    The experience of the Collider Detector at Fermilab (CDF) with aging in the large axial drift chamber responsible for tracking in the central region is presented. Premature aging in the Run 1 chamber was observed after only 0.02 C/cm. After cleaning much of the gas system and making modifications to reduce aerosols from the alcohol bubbler, the observed aging rate fell dramatically in test chambers. Considerable effort has been made to better understand the factors that affect aging since the replacement chamber for Run 2 will accumulate about 1.0 C/cm. Current test chambers using the full CDF gas system show aging rates of less than 5%/C/cm.

  19. Note: Small anaerobic chamber for optical spectroscopy.

    PubMed

    Chauvet, Adrien A P; Agarwal, Rachna; Cramer, William A; Chergui, Majed

    2015-10-01

    The study of oxygen-sensitive biological samples requires an effective control of the atmosphere in which they are housed. In this aim however, no commercial anaerobic chamber is adequate to solely enclose the sample and small enough to fit in a compact spectroscopic system with which analysis can be performed. Furthermore, spectroscopic analysis requires the probe beam to pass through the whole chamber, introducing a requirement for adequate windows. In response to these challenges, we present a 1 l anaerobic chamber that is suitable for broad-band spectroscopic analysis. This chamber has the advantage of (1) providing access, via a septum, to the sample and (2) allows the sample position to be adjusted while keeping the chamber fixed and hermetic during the experiment. PMID:26520998

  20. Note: Small anaerobic chamber for optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Chauvet, Adrien A. P.; Agarwal, Rachna; Cramer, William A.; Chergui, Majed

    2015-10-01

    The study of oxygen-sensitive biological samples requires an effective control of the atmosphere in which they are housed. In this aim however, no commercial anaerobic chamber is adequate to solely enclose the sample and small enough to fit in a compact spectroscopic system with which analysis can be performed. Furthermore, spectroscopic analysis requires the probe beam to pass through the whole chamber, introducing a requirement for adequate windows. In response to these challenges, we present a 1 l anaerobic chamber that is suitable for broad-band spectroscopic analysis. This chamber has the advantage of (1) providing access, via a septum, to the sample and (2) allows the sample position to be adjusted while keeping the chamber fixed and hermetic during the experiment.

  1. Note: Small anaerobic chamber for optical spectroscopy

    SciTech Connect

    Chauvet, Adrien A. P. Chergui, Majed; Agarwal, Rachna; Cramer, William A.

    2015-10-15

    The study of oxygen-sensitive biological samples requires an effective control of the atmosphere in which they are housed. In this aim however, no commercial anaerobic chamber is adequate to solely enclose the sample and small enough to fit in a compact spectroscopic system with which analysis can be performed. Furthermore, spectroscopic analysis requires the probe beam to pass through the whole chamber, introducing a requirement for adequate windows. In response to these challenges, we present a 1 l anaerobic chamber that is suitable for broad-band spectroscopic analysis. This chamber has the advantage of (1) providing access, via a septum, to the sample and (2) allows the sample position to be adjusted while keeping the chamber fixed and hermetic during the experiment.

  2. Emulsions on demand using microsturctured devices

    NASA Astrophysics Data System (ADS)

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

    2003-01-01

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

  3. 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. PMID:26794954

  4. Double emulsions in a microfluidic device

    NASA Astrophysics Data System (ADS)

    Pannacci, Nicolas; Lockhart, Thibaut; Willaime, Hervé; Tabeling, Patrick

    2007-11-01

    Double emulsions (emulsion of two liquids dispersed in a third liquid phase) are widely used in cosmetics, medicine or food industry. We are interested in producing very well controlled double emulsions in a microfluidic device and predicting the morphology (complete engulfing, non-engulfing or partial engulfing called ``janus'') from classical energetic considerations. We use a double flow focusing geometry with a 100 micrometers cross section for the PDMS microsystem. We compare theoretical and experimental morphologies flowing thirty triplets of immiscible fluids. We observe quite a good agreement and show that microfluidic technology may permit to get non standard objects.

  5. 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.

  6. 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.

  7. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sarguisingh, Miriam J.

    2012-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

  8. Hydrodynamic model for drying emulsions

    NASA Astrophysics Data System (ADS)

    Feng, Huanhuan; Sprakel, Joris; van der Gucht, Jasper

    2015-08-01

    We present a hydrodynamic model for film formation in a dense oil-in-water emulsion under a unidirectional drying stress. Water flow through the plateau borders towards the drying end leads to the buildup of a pressure gradient. When the local pressure exceeds the critical disjoining pressure, the water films between droplets break and the droplets coalesce. We show that, depending on the critical pressure and the evaporation rate, the coalescence can occur in two distinct modes. At low critical pressures and low evaporation rates, coalescence occurs throughout the sample, whereas at high critical pressures and high evaporation rate, coalescence occurs only at the front. In the latter case, an oil layer develops on top of the film, which acts as a diffusive barrier and slows down film formation. Our findings, which are summarized in a state diagram for film formation, are in agreement with recent experimental findings.

  9. 45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), VIEW LOOKING EAST. LEAD ENCLOSED PIPING IS DRAIN FROM BOILER CHAMBER No. 1 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  10. Formaldehyde vapor produced from hexamethylenetetramine and pesticide: Simultaneous monitoring of formaldehyde and ozone in chamber experiments by flow-based hybrid micro-gas analyzer.

    PubMed

    Yanaga, Akira; Hozumi, Naruto; Ohira, Shin-Ichi; Hasegawa, Asako; Toda, Kei

    2016-02-01

    Simultaneous analysis of HCHO and O3 was performed by the developed flow analysis system to prove that HCHO vapor is produced from solid pesticide in the presence of O3. HCHO is produced in many ways, including as primary emissions from fuel combustion and in secondary production from anthropogenic and biogenic volatile organic compounds by photochemical reactions. In this work, HCHO production from pesticides was investigated for the first time. Commonly pesticide contains surfactant such as hexamethylenetetramine (HMT), which is a heterocyclic compound formed from six molecules of HCHO and four molecules of NH3. HMT can react with gaseous oxidants such as ozone (O3) to produce HCHO. In the present study, a flow analysis system was developed for simultaneous analysis of HCHO and O3, and this system was used to determine if solid pesticides produced HCHO vapor in the presence of O3. HMT or the pesticide jimandaisen, which contains mancozeb as the active ingradient and HMT as a stabilizer was placed at the bottom of a 20-L stainless steel chamber. Air in the chamber was monitored using the developed flow system. Analyte gases were collected into an absorbing solution by a honeycomb-patterned microchannel scrubber that was previously developed for a micro gas analysis system (μGAS). Subsequently, indigotrisulfonate, a blue dye, was added to the absorbing solution to detect O3, which discolored the solution. HCHO was detected after mixing with the Hantzsch reaction reagent. Both gases could be detected at concentrations ranging from parts per billion by volume (ppbv) to 1000 ppbv with good linearity. Both HMT and jimandaisen emitted large amount of HCHO in the presence of O3. PMID:26653496

  11. Simple cloud chambers using gel ice packs

    NASA Astrophysics Data System (ADS)

    Kamata, Masahiro; Kubota, Miki

    2012-07-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry ice or liquid nitrogen. The gel can be frozen in normal domestic freezers, and can be used repeatedly by re-freezing. The tracks of alpha-ray particles can be observed continuously for about 20 min, and the operation is simple and easy.

  12. Liquid Fuel Emulsion Jet-in-Crossflow Penetration and Dispersion Under High Pressure Conditions

    NASA Astrophysics Data System (ADS)

    Gomez, Guillermo Andres

    The current work focuses on the jet-in-crossflow penetration and dispersion behavior of water-in-oil emulsions in a high pressure environment. Both fuel injection strategies of using a water-in-oil emulsion and a jet-in-crossflow have demonstrated unique benefits in improving gas turbine performance from an emissions and efficiency standpoint. A jet-in-crossflow is very practical for use in gas turbine engines, rocket propulsion, and aircraft engines since it utilizes already available crossflow air to atomize fuel. Injecting water into a combustion chamber in the form of a water-in-oil emulsion allows for pollutant emissions reduction while reducing efficiency loses that may result from using a separate water or steam injection circuit. Dispersion effects on oil droplets are expected, therefore investigating the distribution of both oil and water droplets in the crossflow is an objective in this work. Understanding the synchronization and injection behavior of the two strategies is of key interest due to their combined benefits. A water-to-oil ratio and an ambient pressure parameter are developed for emulsion jet-in-crossflow trajectories. To this end, a total of 24 emulsion jet-in-crossflow tests were performed with varying ambient pressures of 2-8 atm and momentum flux ratios of 50, 85, and 120. Sobel edge filtering was applied to each averaged image obtained from a high speed video of each test case. Averaged and filtered images were used to resolve top and bottom edges of the trajectory in addition to the overall peak intensity up to 40 mm downstream of the injection point. An optimized correlation was established and found to differ from literature based correlations obtained under atmospheric pressure conditions. Overall it was found that additional parameters were not necessary for the top edge and peak intensity correlations, but a need for a unique emulsion bottom edge and width trajectory correlation was recognized. In addition to investigating emulsion

  13. Aging properties of Kodak type 101 emulsions

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  14. How does a bubble chamber work?

    SciTech Connect

    Konstantinov, D.; Homsi, W.; Luzuriaga, J.; Su, C.K.; Weilert, M.A.; Maris, H.J.

    1998-11-01

    A charged particle passing through a bubble chamber produces a track of bubbles. The way in which these bubbles are produced has been a matter of some controversy. The authors consider the possibility that in helium and hydrogen bubble chambers the production of bubbles is primarily a mechanical process, rather than a thermal process as has often been assumed. The model the authors propose gives results which are in excellent agreement with experiment.

  15. The Mars Chamber

    NASA Video Gallery

    The Mars chamber is a box about the size of a refrigerator that re-creates the temperatures, pressures, and atmosphere of the Martian surface, essentially creating a Mars environment on Earth! Scie...

  16. Sleeve reaction chamber system

    SciTech Connect

    Northrup, M. Allen; Beeman, Barton V.; Benett, William J.; Hadley, Dean R.; Landre, Phoebe; Lehew, Stacy L.; Krulevitch, Peter A.

    2009-08-25

    A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

  17. 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

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

    PubMed

    Li, Yilei; Zhu, Zhencai; Chen, Guoan

    2014-01-01

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

  19. Precise measurements of droplet-droplet contact forces in quasi-2D emulsions

    NASA Astrophysics Data System (ADS)

    Lowensohn, Janna; Orellana, Carlos; Weeks, Eric

    2015-03-01

    We use microscopy to visualize a quasi-2D oil-in-water emulsion confined between two parallel slides. We then use the droplet shapes to infer the forces they exert on each other. To calibrate our force law, we set up an emulsion in a tilted sample chamber so that the droplets feel a known buoyant force. By correlating radius of the droplet and length of contacts with the buoyant forces, we validate our empirical force law. We improve upon prior work in our lab by using a high-resolution camera to image each droplet multiple times, thus providing sub-pixel resolution and reducing the noise. Our new technique identifies contact forces with only a 1% uncertainty, five times better than prior work. We demonstrate the utility of our technique by examining the normal modes of the droplet contact network in our samples.

  20. EMC3-Eirene simulations of particle- and energy fluxes to main chamber- and divertor plasma facing components in ASDEX Upgrade compared to experiments

    NASA Astrophysics Data System (ADS)

    Lunt, T.; Carralero, D.; Feng, Y.; Birkenmeier, G.; Müller, H. W.; Müller, S.; Wischmeier, M.

    2015-08-01

    We report on first EMC3-Eirene simulations with an extended computational grid including both divertor- and main chamber (MC) 3D wall plasma-facing components (PFCs). In a first step we compare the simulations to low-power L-mode discharges systematically analyzed by Carralero et al., who observed a transition from a low- to a high density regime (Carralero et al., 2014). Case A is a configuration at low density and high clearance, while B is a high density regime configuration at medium clearance. In order to explain the upstream far-SOL ne profiles of B the MC PFCs and an enhanced transport region at ρ = 1.01, …, 1.03 need to be included in the simulations. In a second step we compute the particle-, and power fluxes to the limiter for the realistic geometry, for limiters displaced radially inward and for a toroidally symmetric limiter. Almost the same fraction of power as that to the divertor is absorbed by the MC PFCs in the simulation of case B.

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

    PubMed Central

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

    2012-01-01

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

  2. 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

  3. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... rolling with emulsions subcategory. 467.20 Section 467.20 Protection of Environment ENVIRONMENTAL... Rolling With Emulsions Subcategory § 467.20 Applicability; description of the rolling with emulsions... the rolling with emulsions subcategory....

  4. Controlled release of insect sex pheromones from paraffin wax and emulsions.

    PubMed

    Atterholt, C A; Delwiche, M J; Rice, R E; Krochta, J M

    1999-02-22

    Paraffin wax and aqueous paraffin emulsions can be used as controlled release carriers for insect sex pheromones for mating disruption of orchard pests. Paraffin can be applied at ambient temperature as an aqueous emulsion, adheres to tree bark or foliage, releases pheromone for an extended period of time, and will slowly erode from bark and biodegrade in soil. Pheromone emulsions can be applied with simple spray equipment. Pheromone release-rates from paraffin were measured in laboratory flow-cell experiments. Pheromone was trapped from an air stream with an adsorbent, eluted periodically, and quantified by gas chromatography. Pheromone release from paraffin was partition-controlled, providing a constant (zero-order) release rate. A typical paraffin emulsion consisted of 30% paraffin, 4% pheromone, 4% soy oil, 1% vitamin E, 2% emulsifier, and the balance water. Soy oil and vitamin E acted as volatility suppressants. A constant release of oriental fruit moth pheromone from paraffin emulsions was observed in the laboratory for more than 100 days at 27 degreesC, with release-rates ranging from 0.4 to 2 mg/day, depending on the concentration and surface area of the dried emulsion. The use of paraffin emulsions is a viable method for direct application of insect pheromones for mating disruption. Sprayable formulations can be designed to release insect pheromones to the environment at a rate necessary for insect control by mating disruption. At temperatures below 38 degreesC, zero-order release was observed. At 38 degreesC and higher, pheromone oxidation occurred. A partition-controlled release mechanism was supported by a zero-order pheromone release-rate, low air/wax partition coefficients, and pheromone solubility in paraffin. PMID:9895411

  5. 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. PMID:27063245

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

    PubMed

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

    2014-08-12

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

  7. Smog chamber experiments to investigate Henry's law constants of glyoxal using different seed aerosols as well as imidazole formation in the presence of ammonia

    NASA Astrophysics Data System (ADS)

    Jakob, Ronit

    2015-04-01

    Aerosols play an important role in the chemistry and physics of the atmosphere. Hence, they have a direct as well as an indirect impact on the earth's climate. Depending on their formation, one distinguishes between primary and secondary aerosols[1]. Important groups within the secondary aerosols are the secondary organic aerosols (SOAs). In order to improve predictions about these impacts on the earth's climate the existing models need to be optimized, because they still underestimate SOA formation[2]. Glyoxal, the smallest α-dicarbonyl, not only acts as a tracer for SOA formation but also as a direct contributor to SOA. Because glyoxal has such a high vapour pressure, it was common knowledge that it does not take part in gas-particle partitioning and therefore has no impact on direct SOA formation. However, the Henry's law constant for glyoxal is surprisingly high. This has been explained by the hydration of the aldehyde groups, which means that a species with a lower vapour pressure is produced. Therefore the distribution of glyoxal between gas- and particle phase is atmospherically relevant and the direct contribution of glyoxal to SOA can no longer be neglected[3]. Besides this particulate glyoxal is able to undergo heterogeneous chemistry with gaseous ammonia to form imidazoles. This plays an important role for regions with aerosols exhibiting alkaline pH values for example from lifestock or soil dust because imidazoles as nitrogen containing compounds change the optical properties of aerosols[4]. A high salt concentration present in chamber seed aerosols leads to an enhanced glyoxal uptake into the particle. This effect is called "salting-in". The salting effect depends on the composition of the seed aerosol as well as the soluble compound. For very polar compounds, like glyoxal, a "salting-in" is observed[3]. Glyoxal particle formation during a smog chamber campaign at Paul-Scherrer-Institut (PSI) in Switzerland was examined using different seed aerosols

  8. Optimization of a closed-loop gas system for the operation of Resistive Plate Chambers at the Large Hadron Collider experiments

    NASA Astrophysics Data System (ADS)

    Capeans, M.; Glushkov, I.; Guida, R.; Hahn, F.; Haider, S.

    2012-01-01

    Resistive Plate Chambers (RPCs), thanks to their fast time resolution (˜1 ns), suitable space resolution (˜1 cm) and low production cost (˜50 €/m2), are widely employed for the muon trigger systems at the Large Hadron Collider (LHC). Their large detector volume (they cover a surface of about 4000 m2 equivalent to 16 m3 of gas volume both in ATLAS and CMS) and the use of a relatively expensive Freon-based gas mixture make a closed-loop gas circulation unavoidable. It has been observed that the return gas of RPCs operated in conditions similar to the difficult experimental background foreseen at LHC contains a large amount of impurities potentially dangerous for long-term operation. Several gas-cleaning agents are currently in use in order to avoid accumulation of impurities in the closed-loop circuits. We present the results of a systematic study characterizing each of these cleaning agents. During the test, several RPCs were operated at the CERN Gamma Irradiation Facility (GIF) in a high radiation environment in order to observe the production of typical impurities: mainly fluoride ions, molecules of the Freon group and hydrocarbons. The polluted return gas was sent to several cartridges, each containing a different cleaning agent. The effectiveness of each material was studied using gas chromatography and mass-spectrometry techniques. Results of this test have revealed an optimized configuration of filters that is now under long-term validation.Gas optimization studies are complemented with a finite element simulation of gas flow distribution in the RPCs, aiming at its eventual optimization in terms of distribution and flow rate.

  9. Posterior chamber collagen copolymer phakic intraocular lens with a central hole for moderate-to-high myopia: First experience in China.

    PubMed

    Cao, Xinfang; Wu, Weiliang; Wang, Yang; Xie, Chen; Tong, Jianping; Shen, Ye

    2016-09-01

    The purpose of this article is to evaluate the clinical outcomes of a posterior chamber phakic intraocular lens (pIOL) (Visian Implantable Collamer Lens V4c) for the correction of moderate to high myopia in Chinese eyes.The article is designed as a retrospective case series.This study included the first consecutive eyes that had implantation of a new pIOL design with a central hole, at our department by the same surgeon. The safety, efficacy, predictability, stability, and adverse events of the surgery were evaluated over 6 months.The study enrolled 63 eyes (32 patients). The mean spherical equivalent decreased from -12.81 ± 3.11 diopters (D) preoperatively to -0.05 ± 0.27 D 6 months postoperatively; 96.8% of eyes were within ±0.50 D of the target and 100% of eyes were within ±1.00 D. All eyes had a decimal uncorrected distance visual acuity of 0.5 (20/40) or better at every follow-up visit. The safety and efficacy indices were 1.42 ± 0.34 and 1.11 ± 0.19, respectively. Postoperatively, the intraocular pressure (IOP) remained stable over time. No significant rises in IOP (including pupillary block) and no secondary cataract were found. After 6 months, the mean vault was 505.2 ± 258.9 μm (range 120-990 μm), and the mean endothelial cell loss was 2.0%.Implantation of the pIOL was safe, effective, predictable, and stable in the correction of moderate-to-high myopia in Han Chinese patients, even without peripheral iridectomy. PMID:27603356

  10. 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

  11. 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)

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

    PubMed

    Choi, Yun-Sang; Kim, Young-Boong; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Park, Jinhee; Kim, Cheon-Jei

    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

  13. 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

  14. Improved Rhenium Thrust Chambers

    NASA Technical Reports Server (NTRS)

    O'Dell, John Scott

    2015-01-01

    Radiation-cooled bipropellant thrust chambers are being considered for ascent/ descent engines and reaction control systems on various NASA missions and spacecraft, such as the Mars Sample Return and Orion Multi-Purpose Crew Vehicle (MPCV). Currently, iridium (Ir)-lined rhenium (Re) combustion chambers are the state of the art for in-space engines. NASA's Advanced Materials Bipropellant Rocket (AMBR) engine, a 150-lbf Ir-Re chamber produced by Plasma Processes and Aerojet Rocketdyne, recently set a hydrazine specific impulse record of 333.5 seconds. To withstand the high loads during terrestrial launch, Re chambers with improved mechanical properties are needed. Recent electrochemical forming (EL-Form"TM") results have shown considerable promise for improving Re's mechanical properties by producing a multilayered deposit composed of a tailored microstructure (i.e., Engineered Re). The Engineered Re processing techniques were optimized, and detailed characterization and mechanical properties tests were performed. The most promising techniques were selected and used to produce an Engineered Re AMBR-sized combustion chamber for testing at Aerojet Rocketdyne.

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

    NASA Technical Reports Server (NTRS)

    Perry, L.

    1973-01-01

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

  16. 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

  17. 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

  18. The DELPHI time projection chamber

    SciTech Connect

    Brand, C.; Cairanti, G.; Charpentier, P.; Clara, M.P.; Delikaris, D.; Foeth, H.; Heck, B.W.; Hilke, H.J.; Sulkowski, K.; Aubret, C.

    1989-02-01

    The central tracking device of the DELPHI Experiment at LEP is a Time Projection Chamber (TPC) with an active volume of 2 x 1.34m in length and 2.22m in diameter. Since spring 1988 the TPC has undergone extensive tests in a cosmic ray set-up. It will be installed in the LEP tunnel by early 1989. This report covers the construction, the read-out electronics and the contribution of the TPC to the DELPHI trigger. Emphasis is given to novelties which are not used in similar detectors.

  19. Pickering emulsions with α-cyclodextrin inclusions: Structure and thermal stability.

    PubMed

    Diaz-Salmeron, Raul; Chaab, Ismail; Carn, Florent; Djabourov, Madeleine; Bouchemal, Kawthar

    2016-11-15

    This paper explores structural, interfacial and thermal properties of two types of Pickering emulsions containing α-cyclodextrin inclusion complexes: on one hand, emulsions were obtained between aqueous solutions of α-cyclodextrin and different oils (fatty acids, olive oil, silicone oil) and on the other hand, emulsions were obtained between these oils, water and micro or nano-platelet suspensions with inclusion complexes of hydrophobically-modified polysaccharides. The emulsions exhibit versatile properties according to the molecular architecture of the oils. Experiments were performed by microcalorimetry, X-ray diffraction and confocal microscopy. The aptitude of oil molecules to be threaded in α-cyclodextrin cavity is a determining parameter in emulsification and thermal stability. The heat flow traces and images showed dissolution, cooperative melting and de-threading of inclusion complexes which take place progressively, ending at high temperatures, close or above 100°C. Another important feature observed in the emulsions with micro-platelets is the partial substitution of the guest molecules occurring at room temperature at the oil/water interfaces without dissolution, possibly by a diffusion mechanism of the oil. Accordingly, the dissolution and the cooperative melting temperatures of the inclusion crystals changed, showing marked differences upon the type of guest molecules. The enthalpies of dissolution of crystals were measured and compared with soluble inclusions. PMID:27491001

  20. Nuclear Emulsion Scanning in Opera:. Methods and Results

    NASA Astrophysics Data System (ADS)

    Bozza, Cristiano

    2008-06-01

    The design of the OPERA experiment was also motivated and justified by the revival of nuclear emulsion handling and scanning in a modem, automatic fashion, as it took previously place, although at a smaller scale, for the CHORUS experiment. Nuclear emulsions are still the only detector to allow a very detailed topological study of an interaction/decay vertex at the sub-micrometer level. They are most suitable in experiments where topology is a non-ambiguous signature of a certain class of events. This is for instance the case of neutrino oscillation detection and measurement by the study of a tau-appearance signal. The design and performance of the two different scanning systems used in OPERA (ESS and S-UTS) are discussed. Their unique features in terms of speed, precision, background suppression, particle identification, and kinematical reconstruction are shown in close connection with the technical details that make them possible. Unequalled precision, almost vanishing background, and a wealth of information about each single event are the results presented.

  1. 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).

  2. 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

  3. 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.

  4. 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.

  5. Filament wound rocket motor chambers

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The design, analysis, fabrication and testing of a Kevlar-49/HBRF-55A filament wound chamber is reported. The chamber was fabricated and successfully tested to 80% of the design burst pressure. Results of the data reduction and analysis from the hydrotest indicate that the chamber design and fabrication techniques used for the chamber were adequate and the chamber should perform adequately in a static test.

  6. Automated soil gas monitoring chamber

    DOEpatents

    Edwards, Nelson T.; Riggs, Jeffery S.

    2003-07-29

    A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within the chamber has been invented. The chamber opens between measurements and therefore does not alter the metabolic processes that influence soil gas efflux rates. A multiple chamber system provides for repetitive multi-point sampling, undisturbed metabolic soil processes between sampling, and an essentially airtight sampling chamber operating at ambient pressure.

  7. 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.

  8. Pickering emulsions stabilized by hydrophilic nanoparticles: in situ surface modification by oil.

    PubMed

    Binks, Bernard P; Yin, Dezhong

    2016-08-10

    We propose a novel route for the stabilization of oil-in-water Pickering emulsions using inherently hydrophilic nanoparticles. In the case of dialkyl adipate oils, in situ hydrophobisation of the particles by dissolved oil molecules in the aqueous phase enables stable emulsions to be formed. Emulsion stability is enhanced upon decreasing the chain length of the oil due to its increased solubility in the precursor aqueous phase. The oil thus acts like a surfactant in this respect in which hydrogen bonds form between the carbonyl group of the ester oil and the hydroxyl group on particle surfaces. The particles chosen include both fumed and precipitated anionic silica and cationic zirconia. Complementary experiments including relevant oil-water-solid contact angles and infra-red analysis of dried particles after contact with oil support the proposed mechanism. PMID:27452321

  9. 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…

  10. Ultrasonic Drying Processing Chamber

    NASA Astrophysics Data System (ADS)

    Acosta, V.; Bon, J.; Riera, E.; Pinto, A.

    The design of a high intensity ultrasonic chamber for drying process was investigated. The acoustic pressure distribution in the ultrasonic drying chamber was simulated solving linear elastic models with attenuation for the acoustic-structure interaction. Together with the government equations, the selection of appropriate boundary conditions, mesh refinement, and configuration parameters of the calculation methods, which is of great importance to simulate adequately the process, were considered. Numerical solution, applying the finite element method (FEM), of acoustic-structure interactions involves to couple structural and fluid elements (with different degrees of freedom), whose solution implies several problems of hardware requirements and software configuration, which were solved. To design the drying chamber, the influence of the directivity of the drying open camera and the staggered reflectors over the acoustic pressure distribution was analyzed. Furthermore, to optimize the influence of the acoustic energy on the drying process, the average value of the acoustic energy distribution in the drying chamber was studied. This would determine the adequate position of the food samples to be dried. For this purpose, the acoustic power absorbed by the samples will be analyzed in later studies.

  11. Improved wire chamber

    DOEpatents

    Atac, M.

    1987-05-12

    An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

  12. Liquid Wall Chambers

    SciTech Connect

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  13. Aging mechanism in model Pickering emulsion.

    PubMed

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

    2016-01-21

    We study the stability of a model Pickering emulsion system using fluorinated oil and functionalized silica nanoparticles. A special counter-flow microfluidic set-up was used to prepare monodisperse 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 microfluidic setup. For surface coverage as low as 23%, we observed a regime of Pickering emulsion stability where the surface coverage of emulsion droplets of constant size increases with time, coexisting with an excess of oil 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. PMID:26549639

  14. Designing an Active Target Test Projection Chamber

    NASA Astrophysics Data System (ADS)

    Koci, James; Tan Ahn Collaboration, Dr.; Nicolas Dixneuf Collaboration

    2015-10-01

    The development of instrumentation in nuclear physics is crucial for advancing our ability to measure the properties of exotic nuclei. One limitation of the use of exotic nuclei in experiment is their very low production intensities. Recently, detectors, called active-target dectectors, have been developed to address this issue. Active-target detectors use a gas medium to image charged-particle tracks that are emitted in nuclear reactions. Last semester, I designed a vacuum chamber to be used in developing Micro-Pattern Gas detectors that will upgrade the capabilities of an active-target detector called the Prototype AT-TPC. With the exterior of the chamber complete, I have now been using an electric field modeling program, Garfield, developed by CERN to design a field cage to be placed within the vacuum chamber. The field cage will be a box-like apparatus consisting of two parallel metal plates connected with a resistor chain and attached to wires wrapped between them. The cage will provide a uniform electric field within the chamber to drift electrons from nuclear reactions down to the detector in the bottom of the chamber. These signals are then amplified by a proportional counter, and the data is sent to a computer. For the long term, we would like to incorporate a Micro-Pattern Gas Detectors in the interior of the chamber and eventually use the AT-TPC to examine various nuclei. Dr. Ahn is my advising professor.

  15. Electrodynamic treatment of reversed-type emulsions

    SciTech Connect

    Skachkov, A.E.; Lavrov, I.S.; Timonov, S.M.

    1985-11-01

    The authors have produced an inhomogeneous electric field in processing reversed emulsions by using the oscillations of conducting spheres in an electric field; this is known as the electrical pendulum effect. The apparatus for the electrodynamic treatment of reversed-type emulsion is shown and the physical characteristics (density, kinematic viscosity, dielectric constant) are shown for the hydrocarbons used: hexane, octane, hexadecane and diesel fuel. It is shown that there is a minimum in the dependence of the residual water content after electrodynamic treatment on the external field strength; the minimum shifts to larger external field strength as the viscosity increases.

  16. Intestinal absorption of dolichol from emulsions and liposomes in rats.

    PubMed

    Kimura, T; Takeda, K; Kageyu, A; Toda, M; Kurosaki, Y; Nakayama, T

    1989-02-01

    The intestinal absorption of dolichol from various dosage forms was investigated using the intestinal loop and everted sac methods in the rat. The in situ loop experiments showed that the absorption of dolichol from a triglyceride emulsion was dependent on the chain-length of the triglyceride; the absorption from a tri-n-butyrin emulsion in 1 h was 18.0% of the dose; and the absorption from an HCO-60 suspension was 4.3%. The liposomal preparation enhanced the absorption up to 39.1% of the dose. In in vitro experiments, 25.0% and 13.2% of dolichol were taken up by everted sacs of the jejunum and the ileum, respectively. On the other hand, phospholipids composing liposomes were not absorbed under these conditions. The above results suggest that the absorption mechanism from liposomal preparations may be as follows: dolichol is released from the liposomes into the aqueous phase adjacent to the surface of the intestine and is subsequently partitioned into the intestinal tissue. PMID:2743494

  17. Multi-chamber deposition system

    DOEpatents

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-10-17

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  18. Multi-chamber deposition system

    DOEpatents

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-06-27

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  19. Combustor with fuel preparation chambers

    NASA Technical Reports Server (NTRS)

    Zelina, Joseph (Inventor); Myers, Geoffrey D. (Inventor); Srinivasan, Ram (Inventor); Reynolds, Robert S. (Inventor)

    2001-01-01

    An annular combustor having fuel preparation chambers mounted in the dome of the combustor. The fuel preparation chamber comprises an annular wall extending axially from an inlet to an exit that defines a mixing chamber. Mounted to the inlet are an air swirler and a fuel atomizer. The air swirler provides swirled air to the mixing chamber while the atomizer provides a fuel spray. On the downstream side of the exit, the fuel preparation chamber has an inwardly extending conical wall that compresses the swirling mixture of fuel and air exiting the mixing chamber.

  20. 50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ENCLOSURE (LOCATION III) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  1. 61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION PPP) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  2. 44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), LOOKING NORTHEAST SHOWING DRAIN PIPE FROM SUMP - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  3. 41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING NORTHEAST FROM SOUTHWEST CORNER (LOCATION AAA) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  4. 72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR AND CANAL (LOCATION T) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  5. Mobility of heavy metals from polluted sediments of a semi-enclosed basin: in situ benthic chamber experiments in Taranto's Mar Piccolo (Ionian Sea, Southern Italy).

    PubMed

    Emili, Andrea; Acquavita, Alessandro; Covelli, Stefano; Spada, Lucia; Di Leo, Antonella; Giandomenico, Santina; Cardellicchio, Nicola

    2016-07-01

    In situ benthic flux experiments were conducted at two stations in the Mar Piccolo of Taranto (Italy), one of the most industrialised and contaminated coastal areas of the Mediterranean. Sediments of the two stations are notably different in their trace metal content, with a station closer to a Navy harbour showing higher mean concentrations of almost all investigated metals (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn). Conversely, both stations are characterised by significant Hg contamination, compared to the local baseline. Results of a sequential extraction scheme on surface sediments suggest a relatively scarce mobility of the examined metals (Zn > Ni > Cr > As > Cu > Pb). A Hg-specific extraction procedure showed that most of the element (93.1 %) occurs in a fraction comprising Hg bound to Fe/Mn oxi-hydroxides. Reduction of these oxides may affect Hg remobilisation and redistribution. Porewater profiles of dissolved trace metals were quite similar in the two sites, although significant differences could be observed for Al, Cu, Fe and Hg. The highest diffusive fluxes were observed for As, Fe and Mn. Mobility rates of several trace elements (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn) were directly measured at the sediment-water interface. Results from benthic in situ incubation experiments showed increasing dissolved metal concentrations with time, resulting in higher fluxes for Cu, Fe, Hg, V and Zn in the most contaminated site. Conversely, fluxes of Mn, Ni and Pb were comparable between the two stations. The estimated flux of Hg (97 μg m(-2) day(-1)) was the highest observed among similar experiments conducted in other highly contaminated Mediterranean coastal environments. Benthic fluxes could be partially explained by considering rates of organic matter remineralisation, dissolution of Fe/Mn oxy-hydroxides and metal speciation in sediments. Seasonal and spatial variation of biogeochemical parameters can influence metal remobilisation in

  6. Three chamber negative ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.; Hiskes, John R.

    1985-01-01

    A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

  7. [Perfluorocarbon emulsions and other corpuscular systems influence on neutrophil activity].

    PubMed

    Shekhtman, D G; Safronova, V G; Sklifas, A N; Alovskaia, A A; Gapeev, A B; Obraztsov, V V; Chemeris, N K

    1997-01-01

    Influence of perfluorodecalin, perfluoromethilcyclohexylpiperidine, perfluorotributylamine emulsions on active oxygen form (AOF) generation by neutrophils has been studied. All investigated emulsions stabilized both proxanol 268 and egg yolk phospholipids inhibited PMA-stimulated neutrophil activity. Castor oil emulsion also inhibited the neutrophil activity. Neutrophil response for chemotactic peptide, was unchanged in the presence of all tested emulsions. We suppose that fast hydrophobic attachment of inert submicrone emulsion particles to cell surface provokes alteration of neutrophil plasma membrane function resulting in a decrease of AOF generation. PMID:9490112

  8. CONTINUOUSLY SENSITIVE BUBBLE CHAMBER

    DOEpatents

    Good, R.H.

    1959-08-18

    A radiation detector of the bubble chamber class is described which is continuously sensitive and which does not require the complex pressure cycling equipment characteristic of prior forms of the chamber. The radiation sensitive element is a gas-saturated liquid and means are provided for establishing a thermal gradient across a region of the liquid. The gradient has a temperature range including both the saturation temperature of the liquid and more elevated temperatures. Thus a supersaturated zone is created in which ionizing radiations may give rise to visible gas bubbles indicative of the passage of the radiation through the liquid. Additional means are provided for replenishing the supply of gas-saturated liquid to maintaincontinuous sensitivity.

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

    PubMed

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

    2014-09-28

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

  10. 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. PMID:26028420

  11. Advanced thrust chamber designs

    NASA Technical Reports Server (NTRS)

    Dietrich, F. J.; Leach, A. E.

    1971-01-01

    A regeneratively cooled thrust chamber has been designed and fabricated, consisting of an inner TD nickel liner which was spin formed, welded, and machined and an outer shell of electroformed nickel. Coolant channels were produced in the outer surface of the inner liner by the electric discharge machining process before electroforming the shell. Accessory manifolds and piping were attached by welding. Manufacturing processes employed are described.

  12. Digital optical spark chambers

    NASA Technical Reports Server (NTRS)

    Evenson, Paul; Tuska, Evelyn

    1989-01-01

    The authors constructed and tested a prototype digital readout system for optical spark chambers using a linear, solid-state charge-coupled-device detector array. Position resolution of 0.013 mm (sigma) over a 25-cm field of view has been demonstrated. It is concluded that this technique should permit the construction of economical, lightweight and low-power trajectory hodoscopes for use in cosmic-ray instrumentation on balloons and in spacecraft.

  13. Surface active agent for emulsion fuel

    SciTech Connect

    Aoki, Y.; Furuyama, Y.; Moriyama, N.

    1980-01-08

    A method is claimed for preparing a water-in-oil emulsion fuel which comprises emulsifying water in oil, in the presence of an emulsifying agency. The improvement comprises using as the emulsifying agent, a surfactant. The formula of this surfactant is presented.

  14. Probing Interfacial Emulsion Stability Controls using Electrorheology

    NASA Astrophysics Data System (ADS)

    Wang, Xiuyu; Brandvik, Amy; Alvarado, Vladimir

    2010-11-01

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

  15. Evaporation from an ionic liquid emulsion.

    PubMed

    Friberg, Stig E

    2007-03-15

    The conditions during evaporation in a liquid crystal-in-ionic liquid microemulsion (LC/microEm) were estimated using the phase diagram of the system. The equations for selected tie lines were established and the coordinates calculated for the sites, at which the evaporation lines crossed the tie lines. These values combined with the coordinates for the phases connecting the tie lines were used to calculate the amounts and the composition of the fractions of the two phases present in the emulsion during the evaporation. One of the emulsion phases was a lamellar liquid crystal and high energy emulsification would lead to the liquid crystal being disrupted to form vesicles. Such a system tenders a unique opportunity to study the interaction between vesicles and normal micelles, which gradually change to inverse micelles over bi-continuous structures. The amount of vesicles in the liquid phase versus the fraction liquid crystal was calculated for two extreme cases of vesicle core size and shell thickness. The limit of evaporation while retaining the vesicle structure was calculated for emulsions of different original compositions assuming the minimum continuous liquid phase to be 50% of the emulsion. PMID:17207810

  16. Radiation dosimetry and spectrometry with superheated emulsions

    NASA Astrophysics Data System (ADS)

    d'Errico, Francesco

    2001-09-01

    Detectors based on emulsions of overexpanded halocarbon droplets in tissue equivalent aqueous gels or soft polymers, known as "superheated drop detectors" or "bubble (damage) detectors", have been used in radiation detection, dosimetry and spectrometry for over two decades. Recent technological advances have led to the introduction of several instruments for individual and area monitoring: passive integrating meters based on the optical or volumetric registration of the bubbles, and active counters detecting bubble nucleations acoustically. These advances in the instrumentation have been matched by the progress made in the production of stable and well-specified emulsions of superheated droplets. A variety of halocarbons are employed in the formulation of the detectors, and this permits a wide range of applications. In particular, halocarbons with a moderate degree of superheat, i.e. a relatively small difference between their operating temperature and boiling point, can be used in neutron dosimetry and spectrometry since they are only nucleated by energetic heavy ions such as those produced by fast neutrons. More recently, halocarbons with an elevated degree of superheat have been utilised to produce emulsions that nucleate with much smaller energy deposition and detect low linear energy transfer radiations, such as photons and electrons. This paper reviews the detector physics of superheated emulsions and their applications in radiation measurements, particularly in neutron dosimetry and spectrometry.

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

    PubMed

    Binks, Bernard P; Tyowua, Andrew T

    2016-04-01

    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. PMID:27002604

  18. 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. PMID:18992799

  19. Characteristics of Nano-emulsion for Cold Thermal Storage

    NASA Astrophysics Data System (ADS)

    Fumoto, Koji; Kawaji, Masahiro; Kawanami, Tsuyoshi

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

  20. [The enhancement effect of emulsion in flame atomic absorption spectrometry].

    PubMed

    Liu, Li-hang; Shen, Chun-yu

    2002-08-01

    A enhancement method of FAAS with emulsion as enhancement agent has been developed. The enhancement effect of emulsion made of three organic solvents (benzene, benzene-propanone, xylene), one organic reagent (dibutyl phthalate) and three emulsifiers (Tween-80, Triton X-100, OP) for iron, nickel, zinc, manganese and lead was studied. The results indicated that the enhancement is satisfactory. The emulsion with maximum enhancement percentage are respectively emulsion of benzene-OP-dibutyl phthalate with 89%, emulsion of xylene-Trition-100-dibutyl phthal with 34%, emulsion of benzene-Trition-100 with 121%, emulsion of benzene-Trition-100-dibutyl phthalate with 38% and 69% in sequence of the above elements. PMID:12938401

  1. Vertical two chamber reaction furnace

    DOEpatents

    Blaugher, R.D.

    1999-03-16

    A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  2. Vertical two chamber reaction furnace

    DOEpatents

    Blaugher, Richard D.

    1999-03-16

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  3. 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

  4. 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. PMID:23266492

  5. Partitioning of Laponite Clay Platelets in Pickering Emulsion Polymerization.

    PubMed

    Brunier, Barthélémy; Sheibat-Othman, Nida; Chevalier, Yves; Bourgeat-Lami, Elodie

    2016-01-12

    Partitioning of laponite disklike clay platelets between polymer particles and bulk aqueous phase was investigated in Pickering surfactant-free emulsion polymerization of styrene. Adsorption of laponite clay platelets plays an important role in the stabilization of this system, influencing the particle size and the number of particles, and, hence, the reaction rate. Adsorption isotherms show that, while the laponite clay platelets are almost fully exfoliated in water, they form multilayers on the surface of the polymer particles by the end of polymerization, as confirmed by transmission electron microscopy (TEM). This observation is supported by quartz crystal microbalance, conductivity, and TEM measurements, which reveal interactions between the clay and polystyrene, as a function of the ionic strength. The strong adsorption of clay platelets leaves a low residual concentration in the aqueous phase that cannot cause further nucleation of polymer particles, as demonstrated during seeded emulsion polymerization experiments in the presence of a high excess of clay. A Brunauer-Emmett-Teller (BET)-type model for laponite adsorption on polystyrene particles matches the adsorption isotherms. PMID:26653971

  6. The fast Ice Nucleus chamber FINCH

    NASA Astrophysics Data System (ADS)

    Bundke, U.; Nillius, B.; Jaenicke, R.; Wetter, T.; Klein, H.; Bingemer, H.

    2008-11-01

    We present first results of our new developed Ice Nucleus (IN) counter FINCH from the sixth Cloud and Aerosol Characterization Experiment (CLACE 6) campaign at Jungfraujoch station, 3571 m asl. Measurements were made at the total and the ICE CVI inlet. Laboratory measurements of ice onset temperatures by FINCH are compared to those of the static diffusion chamber FRIDGE (FRankfurt Ice Deposition Freezing Experiment). Within the errors of both new instruments the results compare well to published data.

  7. Hollow periodic mesoporous organosilica nanospheres by a facile emulsion approach.

    PubMed

    Ma, Xiaobo; Zhang, Junjie; Dang, Meng; Wang, Jin; Tu, Zenzen; Yuwen, Lihui; Chen, Guotao; Su, Xiaodan; Teng, Zhaogang

    2016-08-01

    Periodic mesoporous organosilicas (PMOs) with homogeneously incorporated organic groups, highly ordered mesopores, and controllable morphology have attracted increasing attention. In this work, one-step emulsion approach for preparation of hollow periodic mesoporous organosilica (HPMO) nanospheres has been established. The method is intrinsically simple and does not require any sacrificial templates, corrosive and toxic etching agents. The obtained HPMO nanospheres have high surface area (∼950m(2)g(-1)), accessible ordered mesochannels (∼3.4nm), large pore volume (∼3.96cm(3)g(-1)), high condensation degree (77%), and diameter (∼560nm), hollow chamber size (∼400nm), and shell thickness (∼80nm). Furthermore, cytotoxicity show the cell viability is higher than 86% after incubating with the HPMO nanospheres at a concentration of up to 1200μgmL(-1) for 24h. The hemolysis of HPMO nanospheres is lower than 1.1% at concentrations ranging from 10 to 2000μgmL(-1). The lower hemolysis and cytotoxicity make the HPMO nanospheres great promise for future biomedical applications. PMID:27156086

  8. A new plant chamber facility PLUS coupled to the atmospheric simulation chamber SAPHIR

    NASA Astrophysics Data System (ADS)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2015-11-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been build and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees are mixed with synthetic air and are transferred to the SAPHIR chamber where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOC) can be studied in detail. In PLUS all important enviromental parameters (e.g. temperature, PAR, soil RH etc.) are well-controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leafes of the plants is constructed such that gases are exposed to FEP Teflon film and other Teflon surfaces only to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 LED panels which have an emission strength up to 800 μmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOC) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light and temperature dependent BVOC emissions are studied using six Quercus Ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus Ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental set up and the utility of the newly added plant chamber.

  9. A new plant chamber facility, PLUS, coupled to the atmosphere simulation chamber SAPHIR

    NASA Astrophysics Data System (ADS)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2016-03-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been built and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow-through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees is mixed with synthetic air and transferred to the SAPHIR chamber, where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOCs) can be studied in detail. In PLUS all important environmental parameters (e.g., temperature, photosynthetically active radiation (PAR), soil relative humidity (RH)) are well controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leaves of the plants is constructed such that gases are exposed to only fluorinated ethylene propylene (FEP) Teflon film and other Teflon surfaces to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 light-emitting diode (LED) panels, which have an emission strength up to 800 µmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOCs) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light- and temperature- dependent BVOC emissions are studied using six Quercus ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental setup and the utility of the newly added plant chamber.

  10. Multi-anode ionization chamber

    DOEpatents

    Bolotnikov, Aleksey E.; Smith, Graham; Mahler, George J.; Vanier, Peter E.

    2010-12-28

    The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

  11. Emulsion properties of casein and whey protein hydrolysates and the relation with other hydrolysate characteristics.

    PubMed

    van der Ven, C; Gruppen, H; de Bont, D B; Voragen, A G

    2001-10-01

    Casein and whey protein were hydrolyzed using 11 different commercially available enzyme preparations. Emulsion-forming ability and emulsion stability of the digests were measured as well as biochemical properties with the objective to study the relations between hydrolysate characteristics and emulsion properties. All whey protein hydrolysates formed emulsions with bimodal droplet size distributions, signifying poor emulsion-forming ability. Emulsion-forming ability of some casein hydrolysates was comparable to that of intact casein. Emulsion instability was caused by creaming and coalescence. Creaming occurred mainly in whey hydrolysate emulsions and in casein hydrolysate emulsions containing large emulsion droplets. Coalescence was dominant in casein emulsions with a broad particle size distribution. Emulsion instability due to coalescence was related to apparent molecular weight distribution of hydrolysates; a relative high amount of peptides larger than 2 kDa positively influences emulsion stability. PMID:11600059

  12. Wire chambers revisited.

    PubMed

    Ott, R J

    1993-04-01

    Detectors used for radioisotope imaging have, historically, been based on scintillating crystal/photomultiplier combinations in various forms. From the rectilinear scanner through to modern gamma cameras and positron cameras, the basic technology has remained much the same. Efforts to overcome the limitations of this form of technology have foundered on the inability to reproduce the required sensitivity, spatial resolution and sensitive area at acceptable cost. Multiwire proportional chambers (MWPCs) have long been used as position-sensitive charged particle detectors in nuclear and high-energy physics. MWPCs are large-area gas-filled ionisation chambers in which large arrays of fine wires are used to measure the position of ionisation produced in the gas by the passage of charged particles. The important properties of MWPCs are high-spatial-resolution, large-area, high-count-rate performance at low cost. For research applications, detectors several metres square have been built and small-area detectors have a charged particle resolution of 0.4 mm at a count rate of several million per second. Modification is required to MWPCs for nuclear medicine imaging. As gamma rays or X-rays cannot be detected directly, they must be converted into photo- or Compton scatter electrons. Photon-electron conversion requires the use of high atomic number materials in the body of the chamber. Pressurised xenon is the most useful form of "gas only" photon-electron convertor and has been used successfully in a gamma camera for the detection of gamma rays at energies below 100 keV. This camera has been developed specifically for high-count-rate first-pass cardiac imaging. This high-pressure xenon gas MWPC is the key to a highly competitive system which can outperform scintillator-based systems. The count rate performance is close to a million counts per second and the intrinsic spatial resolution is better than the best scintillator-based camera. The MWPC camera produces quantitative

  13. Review of wire chamber aging

    SciTech Connect

    Va'Vra, J.

    1986-02-01

    This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs.

  14. Study of hadron bundles observed in Chacaltaya two-story emulsion chamber

    NASA Technical Reports Server (NTRS)

    Aoki, H.

    1985-01-01

    The existence of hadron-rich families associated with few gamma-ray emission named Centauro and Mini-Centauro phemonena was reported. It was investigated whether these are produced by the special type of interaction different from the ordinary pion multiple production or not. The experimental results are compared with simulation calculation based on ordinary multiple pion production model. Both hadron multiplicity distribution, obtained from the present observation and the simulation calculation, show almost the same distribution which means that hadron bundles of such smaller multiplicities are considered to originate from successive interactions of surviving nucleon with the nature of multiple production during passage through the atmosphere.

  15. Crocin loaded nano-emulsions: Factors affecting emulsion properties in spontaneous emulsification.

    PubMed

    Mehrnia, Mohammad-Amin; Jafari, Seid-Mahdi; Makhmal-Zadeh, Behzad S; Maghsoudlou, Yahya

    2016-03-01

    Spontaneous emulsification may be used for encapsulating bioactive compounds in food and pharmaceutical industry. It has several advantages over high energy and other low energy methods including, protecting sensitive compounds against severe conditions of high energy method and its ability to minimize surfactant, removal of cosurfactant and thermal stability compared with other low energy methods. In this study, we examined possibility of encapsulating highly soluble crocin in W/O micro-emulsions using spontaneous method which further could be used for making double emulsions. Nonionic surfactants of Span 80 and polyglycerol polyricinoleate (PGPR) were used for making micro-emulsions that showed the high potential of PGPR for spontaneous method. Surfactant to water ratio (SWR%) was evaluated to find the highest amount of aqueous phase which can be dispersed in organic phase. Droplet size decreased by increasing SWR toward the SWR=100% which had the smallest droplet size and then increased at higher levels of surfactant. By increasing SWR, shear viscosity increased which showed the high effect of PGPR on rheological properties. This study shows in addition to W/O micro-emulsions, spontaneous method could be used for preparing stable O/W micro-emulsions. PMID:26708427

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

    PubMed

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

    2015-03-01

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

  17. 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. PMID:25640680

  18. A new application of emulsions to measure the gravitational force on antihydrogen

    NASA Astrophysics Data System (ADS)

    Amsler, C.; Ariga, A.; Ariga, T.; Braccini, S.; Canali, C.; Ereditato, A.; Kawada, J.; Kimura, M.; Kreslo, I.; Pistillo, C.; Scampoli, P.; Storey, J. W.

    2013-02-01

    We propose to build and operate a detector based on the emulsion film technology for the measurement of the gravitational acceleration on antimatter, to be performed by the AEgIS experiment (AD6) at CERN. The goal of AEgIS is to test the weak equivalence principle with a precision of 1% on the gravitational acceleration g by measuring the vertical position of the annihilation vertex of antihydrogen atoms after their free fall while moving horizontally in a vacuum pipe. With the emulsion technology developed at the University of Bern we propose to improve the performance of AEgIS by exploiting the superior position resolution of emulsion films over other particle detectors. The idea is to use a new type of emulsion films, especially developed for applications in vacuum, to yield a spatial resolution of the order of one micron in the measurement of the sag of the antihydrogen atoms in the gravitational field. This is an order of magnitude better than what was planned in the original AEgIS proposal.

  19. 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. PMID:21459510

  20. Texture and stability of emulsions and suspensions: role of oscillatory structural forces.

    PubMed

    Wasan, D T; Nikolov, A D; Aimetti, F

    2004-05-20

    The stability of macro-dispersions, such as emulsions and particle suspensions, is characterized in different ways-creaming or sedimentation, flocculation of drops/particles, coalescence between drops or phase separation. Several novel experimental techniques have been developed in our laboratory to examine both the texture and stability of emulsions and suspensions. These methods include direct image analysis to extract the emulsion radial distribution function and to determine the effective inter-droplet interaction, and the Kossel diffraction technique, which is used to obtain the structural factors. The film thinning interferometric technique employing our capillary force balance is used to study the role of the surfactant micelles/colloidal particle-layering phenomenon and the in-layer structure formation. Monte Carlo simulations and a theoretical model based on the Ornstein-Zernike equation of statistical mechanics are used to discern the effects of the micelle/particle structuring and layering phenomenon in confined films between two droplets/particles. These experiments and theoretical calculations are used to gain a fundamental understanding of the role of long-range oscillatory (repulsion/attraction) structural interactions on the stability of both mono- and polydispersed systems. During the past 10 years, our research group has worked on several problems of interest to industry in which structural forces in emulsions and suspensions appear to play an important role. This paper is an overview of some of these relevant examples. PMID:15072941

  1. 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. PMID:26394745

  2. Emulsion characteristics, chemical and textural properties of meat systems produced with double emulsions as beef fat replacers.

    PubMed

    Serdaroğlu, Meltem; Öztürk, Burcu; Urgu, Müge

    2016-07-01

    In recent years, double emulsions are stated to have a promising potential in low-fat food production, however, there are very few studies on their possible applications in meat matrices. We aimed to investigate the quality of beef emulsion systems in which beef fat was totally replaced by double emulsions (W1/O/W2) prepared with olive oil and sodium caseinate (SC) by two-step emulsification procedure. Incorporation of W1/O/W2 emulsion resulted in reduced lipid, increased protein content, and modified fatty acid composition. W1/O/W2 emulsion treatments had lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with beef fat. Increased concentrations of W1/O/W2 emulsions resulted in significant changes in texture parameters. TBA values were lower in W1/O/W2 emulsion treatments than control treatment after 60days of storage. In conclusion, our study confirms that double emulsions had promising impacts on modifying fatty acid composition and developing both technologically and oxidatively stable beef emulsion systems. PMID:26995773

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

    PubMed

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

    2014-01-01

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

  4. Heavy crude oils/particle stabilized emulsions.

    PubMed

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

    2011-12-12

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

  5. Analytical applications of emulsions and microemulsions.

    PubMed

    Burguera, José Luis; Burguera, Marcela

    2012-07-15

    Dispersion systems like emulsions and microemulsions are able to solubilize both polar and non-polar substances due to the special arrangement of the oil and aqueous phases. The main advantages of using emulsions or microemulsions in analytical chemistry are that they do not require the previous destruction of the sample matrix or the use of organic solvents as diluents, and behave similarly to aqueous solutions, frequently allowing the use of aqueous standard solutions for calibration. However, it appears that there are many contradictory concepts and misunderstandings often related to terms definition when referring to such systems. The main aim of this review is to outline the differences between these two aggregates and to give an overview of the most recent advances on their analytical applications with emphasis on the potentiality of the on-line emulsification processes. PMID:22817921

  6. In Situ Assembly of Hydrophilic and Hydrophobic Nanoparticles at Oil-Water Interfaces as a Versatile Strategy To Form Stable Emulsions.

    PubMed

    Saha, Amitesh; John, Vijay T; Bose, Arijit

    2015-09-30

    We report a conceptually new strategy for forming particle-stabilized emulsions. We begin with stable, dilute suspensions of highly hydrophilic nanoparticles in water and hydrophobic nanoparticles in oil. When the two suspensions are mixed, attractive interactions between the hydrophilic and hydrophobic particles cause them to assemble at the oil-water interfaces into partially wettable or Janus-like clusters that effectively stabilize emulsions. By tuning the ratio of hydrophilic to hydrophobic particles in the clusters, both water-in-oil as well as oil-in-water emulsions can be formed. The van der Waals interaction energy between two particle types across an aqueous-organic interface provide a systematic guide to particle and liquid combinations that can form stable emulsions using our strategy, or identify when emulsions will not form. Our experiments and analysis provide a new platform for the formation of particle-stabilized emulsions and can be used to combine particles of different functionalities at emulsion droplet surfaces for generating novel materials. PMID:26372053

  7. 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.

  8. Turbulent flow of oil-water emulsions with polymer additives

    NASA Astrophysics Data System (ADS)

    Manzhai, V. N.; Monkam Clovis Le Grand, Monkam; Abdousaliamov, A. V.

    2014-08-01

    The article outlines direct and reverse oil-water emulsions. Microphotography study of these emulsions was carried out. The effect of water-soluble and oil soluble polymers on the emulsion structure and their turbulent flow velocity in cylindrical channel was investigated. It has been experimentally proven that if the fluid being transported is not homogeneous, but a two-phase oil-water emulsion, only the polymer that is compatible with dispersion medium and capable of dissolving in this medium can reduce the hydrodynamic resistance of the fluid flow. Thus, the resistance in direct emulsions can be reduced by water- soluble polyacrylamide, while oil-soluble polyhexene can be applied for reverse emulsions.

  9. Simple and double emulsions via electrospray

    NASA Astrophysics Data System (ADS)

    Barrero, Antonio; Loscertales, Ignacio G.

    2005-11-01

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

  10. [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. PMID:24160194

  11. 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

  12. Method for purifying solids-stabilized emulsions

    SciTech Connect

    Knowlton, H.E.

    1987-08-25

    A method is described for purifying oil contaminated with both solids and water capable of forming a solids-stabilized emulsion layer which comprises: (a) settling the contaminated oil essentially without agitation in a first vessel, at a temperature of between 50/sup 0/C and 95/sup 0/C, to form an upper partially purified oil layer, an intermediate first oil cuff layer including a solids-stabilized emulsion of oil and 5 to 80 weight percent of solids and water, and a lower first water layer, and withdrawing water from the first water layer; (b) settling the partially purified oil essentially without agitation in a second vessel, at a temperature of between 50/sup 0/C and 95/sup 0/C, to form an upper purified oil layer, an intermediate second oil cuff layer including a solids-stabilized emulsion of oil and 5 to 80 weight percent of solids and water, and a lower second water layer, and providing purified oil containing not more than 2 weight percent of solids and water from the purified oil layer; and (c) settling the intermediate first and second oil cuff layers essentially without agitation in a third vessel, at a temperature between 50/sup 0/C and 95/sup 0/C , to form an upper layer including oil and 5 to 80 weight percent of solids and water and a lower third water layer.

  13. Diogene pictorial drift chamber

    SciTech Connect

    Gosset, J.

    1984-01-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive).

  14. Mush Column Magma Chambers

    NASA Astrophysics Data System (ADS)

    Marsh, B. D.

    2002-12-01

    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  15. Successful Treatment of Propafenone Intoxication With Intravenous Lipid Emulsion.

    PubMed

    Bayram, Başak; Köse, Işıl; Avcı, Sinem; Arslan, Abdulla; Acara, Çağdaş

    2015-10-01

    Severe cardiac effects, including cardiac arrest, are a rare complication of high-dose propafenone intake. Among patients who experience cardiac arrest, the survival rate is low. This report presents the case of a young female patient who developed cardiac arrest linked to propafenone intake. While spontaneous circulation was restored with cardiopulmonary resuscitation, vital signs did not recover despite supportive treatment. However, after the administration of intravenous lipid emulsion (ILE), vital signs and cardiac functions resolved and the patient survived. This case is the second to describe the successful use of ILE for propafenone intoxication. However, as all of the findings of this patient were clearly linked to propafenone, we believe the benefits of ILE were more clearly defined in this case than in the other. PMID:26497484

  16. 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.

  17. 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

  18. HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF PLENUM WITH ATTACHED DRAFT REGULATOR. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  19. Hydrologic Impacts of a Surface-Applied, Organic Emulsion on Arid Soils

    NASA Astrophysics Data System (ADS)

    Young, M. H.; Caldwell, T. G.; Goreham, J.; Meadows, D. G.; Shafer, D. S.; Miller, J. J.; McDonald, E. V.

    2005-12-01

    In-place stabilization of environmental contaminants over land areas poses interesting logistical challenges, especially when considering the impact of the stabilizing agent on soil hydrologic processes like infiltration and surface runoff. As one part of a larger field-based study, we investigated the potential hydrologic impacts of using an organic-based emulsion which was designed to stabilize disturbed and undisturbed desert soils. The emulsion, a blend of organic esters, surfactants, water, and a proprietary chelating agent, was tested at the Yuma Proving Ground, Yuma, AZ. The goal of the study was to determine whether, and to what extent, field application of this emulsion altered the soil hydraulic properties and hence the infiltration and runoff potential. A randomized complete block design was used to investigate the effects of soil age (old vs young), treatment concentration (control vs two dilution levels), disturbance level (disturbed vs undisturbed), and time (1 year exposure) on the soil hydraulic properties. Hydraulic properties were determined using a 20 cm diameter tension infiltrometer (triplicate measurements for each treatment combination). Initial results show a significant reduction in the saturated hydraulic conductivity by nearly two orders of magnitude following treatment with the emulsion. Triplicate rainfall simulation experiments were also conducted on the test plots to investigate rainfall-runoff processes. Results immediately following treatment show a reduced time to ponding and a higher potential for surface runoff. Tests conducted quarterly for one year after application, however, indicate that hydrologic impacts diminished with time. Targeted laboratory tests are ongoing to better identify the breakdown mechanisms of the emulsion. The field and laboratory results will help guide larger-scale field applications based on actual field conditions.

  20. Costs and Benefits of Underground Pupal Chambers Constructed by Insects: A Test Using Manduca sexta.

    PubMed

    Sprague, Jonathan C; Woods, H Arthur

    2015-01-01

    Many holometabolous insects metamorphose in belowground pupal chambers. Although the chambers may be elaborate and their construction costly, their functions are unknown. Using laboratory and field experiments, we examined the costs and functions of chambers made by the hawk moth Manduca sexta (Sphingidae). Costs were large in some circumstances; prepupal larvae lost up to 60% of their body mass when constructing chambers in dry soils. We tested three alternative hypotheses about what, if anything, chambers do for the individuals that make them: (1) chambers provide critical open space underground, allowing room for ecdysis and preventing soil from deforming the metamorphosing individual; (2) chambers raise the local relative humidity, so that cuticular and respiratory water losses are minimized; and (3) chamber walls prevent predators and pathogens from attacking. The data support the first hypothesis (about open space) and largely exclude the other two. These results provide a simple and potentially broad explanation for the evolution of chamber building in metamorphosing insects. PMID:26658249

  1. Detecting dark matter with scintillating bubble chambers

    NASA Astrophysics Data System (ADS)

    Zhang, Jianjie; Dahl, C. Eric; Jin, Miaotianzi; Baxter, Daniel

    2016-03-01

    Threshold based direct WIMP dark matter detectors such as the superheated bubble chambers developed by the PICO experiment have demonstrated excellent electron-recoil and alpha discrimination, excellent scalability, ease of change of target fluid, and low cost. However, the nuclear-recoil like backgrounds have been a limiting factor in their dark matter sensitivity. We present a new type of detector, the scintillating bubble chamber, which reads out the scintillation pulse of the scattering events as well as the pressure, temperature, acoustic traces, and bubble images as a conventional bubble chamber does. The event energy provides additional handle to discriminate against the nuclear-recoil like backgrounds. Liquid xenon is chosen as the target fluid in our prototyping detector for its high scintillation yield and suitable vapor pressure which simplifies detector complexity. The detector can be used as an R&D tool to study the backgrounds present in the current PICO bubble chambers or as a prototype for standalone dark matter detectors in the future. Supported by DOE Grant DE-SC0012161.

  2. Crude oil emulsions containing a compatible fluorochemical surfactant

    SciTech Connect

    Karydas, A.; Rodgers, J.

    1991-02-19

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

  3. Double inversion of emulsions induced by salt concentration.

    PubMed

    Zhang, Jingchun; Li, Lu; Wang, Jun; Sun, Haigang; Xu, Jian; Sun, Dejun

    2012-05-01

    The effects of salt on emulsions containing sorbitan oleate (Span 80) and Laponite particles were investigated. Surprisingly, a novel double phase inversion was induced by simply changing the salt concentration. At fixed concentration of Laponite particles in the aqueous phase and surfactant in paraffin oil, emulsions are oil in water (o/w) when the concentration of NaCl is lower than 5 mM. Emulsions of water in oil (w/o) are obtained when the NaCl concentration is between 5 and 20 mM. Then the emulsions invert to o/w when the salt concentration is higher than 50 mM. In this process, different emulsifiers dominate the composition of the interfacial layer, and the emulsion type is correspondingly controlled. When the salt concentration is low in the aqueous dispersion of Laponite, the particles are discrete and can move to the interface freely. Therefore, the emulsions are stabilized by particles and surfactant, and the type is o/w as particles are in domination. At intermediate salt concentrations, the aqueous dispersions of Laponite are gel-like, the viscosity is high, and the transition of the particles from the aqueous phase to the interface is inhibited. The emulsions are stabilized mainly by lipophilic surfactant, and w/o emulsions are obtained. For high salt concentration, flocculation occurs and the viscosity of the dispersion is reduced; thus, the adsorption of particles is promoted and the type of emulsions inverts to o/w. Laser-induced fluorescent confocal micrographs and cryo transmission electron microscopy clearly confirm the adsorption of Laponite particles on the surface of o/w emulsion droplets, whereas the accumulation of particles at the w/o emulsion droplet surfaces was not observed. This mechanism is also supported by the results of rheology and interfacial tension measurements. PMID:22475400

  4. Characteristics of a large system of pad readout wire proportional chambers for the HPC calorimeter

    SciTech Connect

    Camporesi, T.; Cavallo, F.R.; Giordano, V.; Laurenti, G.; Molinari, G.; Navarria, F.L.; Privitera, P.; Rovelli, T.; Valenti, G.; Zucchini, A.

    1989-02-01

    A large system of wire proportional chambers is being constructed for the readout of the High-Density Projection Chamber (HPC) of the DELPHI experiment at the Large Electron-Positron storage ring. The system consists of 144 chambers, each 0.3 m/sup 2/ wide and read out via cathode pads, located at the end of the HPC drift volume.

  5. On-Orbit Daytime Solar Heating Effects: A Comparison of Ground Chamber Arcing Results

    NASA Technical Reports Server (NTRS)

    Galofaro, J.; Vayner, B.; Ferguson, D.

    2004-01-01

    The purpose of the current experiment is to make direct comparisons between the arcing results obtained from the diffusion pumped vertical chamber and our newly renovated Teney vacuum chamber which is equipped with a cryogenic pump. Recall that the prior reported results obtained for the Vertical chamber were nominal at best, showing only a slight reduction in the arc rate after five heating cycles at the lower bias potentials and virtually no changes at high potential biases. It was concluded that the vertical chamber was unable to remove enough water vapor from the chamber to adequately test the arcing criterion. Because the cryo-pumped Teney chamber has a ten times better pumping speed, (40,000 liters per sec compared to 4,000 liters per sec for the diffusion pumped vertical chamber), a decision was made to retest that experiment in both the Teney and Vertical vacuum chambers. A comparison of the various data is presented with encouraging results.

  6. On Orbit Daytime Solar Heating Effects: A Comparison of Ground Chamber Arcing Results

    NASA Technical Reports Server (NTRS)

    Galofaro, J.; Vayner, B.; Ferguson, D.

    2004-01-01

    The purpose of the current experiment is to make direct comparisons between the arcing results obtained from the diffusion pumped vertical chamber and our newly renovated Teney vacuum chamber which is equipped with a cryogenic pump. Recall that the prior reported results obtained for the Vertical chamber were nominal at best, showing only a slight reduction in the arc rate after 5 heating cycles at the lower bias potentials and virtually no changes at high potential biases. It was concluded that the vertical chamber was unable to remove enough water vapor from the chamber to adequately test the arcing criterion. Because the cryo-pumped Teney chamber has a ten times better pumping speed, (40,000 liters per sec compared to 4,000 liters per sec for the diffusion pumped vertical chamber), a decision was made to retest that experiment in both the Teney and Vertical vacuum chambers. A comparison of the various data is presented with encouraging results.

  7. Small rocket flowfield diagnostic chambers

    NASA Technical Reports Server (NTRS)

    Morren, Sybil; Reed, Brian

    1993-01-01

    Instrumented and optically-accessible rocket chambers are being developed to be used for diagnostics of small rocket (less than 440 N thrust level) flowfields. These chambers are being tested to gather local fluid dynamic and thermodynamic flowfield data over a range of test conditions. This flowfield database is being used to better understand mixing and heat transfer phenomena in small rockets, influence the numerical modeling of small rocket flowfields, and characterize small rocket components. The diagnostic chamber designs include: a chamber design for gathering wall temperature profiles to be used as boundary conditions in a finite element heat flux model; a chamber design for gathering inner wall temperature and static pressure profiles; and optically-accessible chamber designs, to be used with a suite of laser-based diagnostics for gathering local species concentration, temperature, density, and velocity profiles. These chambers were run with gaseous hydrogen/gaseous oxygen (GH2/GO2) propellants, while subsequent versions will be run on liquid oxygen/hydrocarbon (LOX/HC) propellants. The purpose, design, and initial test results of these small rocket flowfield diagnostic chambers are summarized.

  8. Fast-response cloud chamber

    NASA Technical Reports Server (NTRS)

    Fogal, G. L.

    1977-01-01

    Wall structure keeps chambers at constant, uniform temperature, yet allows them to be cooled rapidly if necessary. Wall structure, used in fast-response cloud chamber, has surface heater and coolant shell separated by foam insulation. It is lightweight and requires relatively little power.

  9. Chamber Music: Skills and Teamwork.

    ERIC Educational Resources Information Center

    Villarrubia, Charles

    2000-01-01

    Focuses on the benefits of participating in chamber music ensembles, such as the development of a heightened level of awareness, and considers the role of the music educator/conductor. Provides tools and exercises that teachers can introduce to chamber music players to improve their rehearsals and performances. (CMK)

  10. LRL 25-inch Bubble Chamber

    DOE R&D Accomplishments Database

    Alvarez, L. W.; Gow, J. D.; Barrera, F.; Eckman, G.; Shand, J.; Watt, R.; Norgren, D.; Hernandez, H. P.

    1964-07-08

    The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system.

  11. Calibration of PICO Bubble Chamber Dark Matter Detectors

    NASA Astrophysics Data System (ADS)

    Jin, Miaotianzi; PICO Collaboration

    2016-03-01

    The PICO Collaboration builds bubble chambers for the direct detection of WIMP dark matter. I will present the suite of calibration experiments performed to measure the sensitivity of these chambers to nuclear recoils (the expected WIMP signal) and to gamma rays (a common background to the WIMP signal). These calibrations include measurements with a 10-ml C3F8 bubble chamber at Northwestern University and with a 30-ml C3F8 bubble chamber deployed in the University of Montreal's tandem Van de Graaf facility, giving the bubble chamber response to a variety of gamma rays, broad-spectrum neutron sources, and mono-energetic low energy neutrons. I will compare our measured sensitivities to those predicted by a simple thermodynamic model and will show how the results impact our ability to detect dark matter, with a focus on light WIMP searches. Supported by DOE Grant: DE-SC0012161.

  12. Plant growth chamber based on space proven controlled environment technology

    SciTech Connect

    Ignatius, R.W.; Ignatius, M.H.; Imberti, H.J.

    1997-01-01

    Quantum Devices, Inc., in conjunction with Percival Scientific, Inc., and the Wisconsin Center for Space Automation and Robotics (WCSAR) have developed a controlled environment plant growth chamber for terrestrial agricultural and scientific applications. This chamber incorporates controlled environment technology used in the WCSAR ASTROCULTURE{trademark} flight unit for conducting plant research on the Space Shuttle. The new chamber, termed CERES 2010, features air humidity, temperature, and carbon dioxide control, an atmospheric contaminant removal unit, an LED lighting system, and a water and nutrient delivery system. The advanced environment control technology used in this chamber will increase the reliability and repeatability of environmental physiology data derived from plant experiments conducted in this chamber. {copyright} {ital 1997 American Institute of Physics.}

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  14. National Ignition Facility Target Chamber

    SciTech Connect

    Wavrik, R W; Cox, J R; Fleming, P J

    2000-10-05

    On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This was

  15. Ion chamber based neutron detectors

    DOEpatents

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  16. 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...

  17. Proton beam monitor chamber calibration.

    PubMed

    Gomà, C; Lorentini, S; Meer, D; Safai, S

    2014-09-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences-of the order of 3%-were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth-i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers-rather than cylindrical chambers-for the reference dosimetry of pseudo-monoenergetic proton beams. PMID:25109620

  18. High-energy Physics with Hydrogen Bubble Chambers

    DOE R&D Accomplishments Database

    Alvarez, L. W.

    1958-03-07

    Recent experience with liquid hydrogen bubble chambers of 25 and 40 cm dia. in high-energy physics experiments is discussed. Experiments described are: interactions of K{sup -} mesons with protons, interactions of antiprotons with protons, catalysis of nuclear fusion reactions by muons, and production and decay of hyperons from negative pions. (W.D.M.)

  19. Telerobotic Tending of Space Based Plant Growth Chamber

    NASA Technical Reports Server (NTRS)

    Backes, P. G.; Long, M. K.; Das, H.

    1994-01-01

    The kinematic design of a telerobotic mechanism for tending a plant growth space science experiment chamber is described. Ground based control of tending mechanisms internal to space science experiments will allow ground based principal investigators to interact directly with their space science experiments.

  20. Glycosylated polyacrylate nanoparticles by emulsion polymerization.

    PubMed

    Abeylath, Sampath C; Turos, Edward

    2007-08-01

    A selection of glycosylated polyacrylate nanoparticles has been prepared by radical-initiated emulsion polymerization in aqueous media. Using ethyl acrylate as a co-monomer, carbohydrate acrylates were incorporated into the poly(ethyl acrylate) framework to give stable emulsions of glyconanoparticles with an average particle size of around 40 nm. Using this technique a variety of glyconanoparticles were prepared from 3-O-acryloyl-1,2:5,6-di-O-isopropylidene-alpha-D-glucofuranose, 1-O-acryloyl-2,3:5,6-di-O-isopropylidene-alpha-D-mannofuranose, 6-O-acryloyl-1,2:3,4-di-O-isopropylidene-alpha-D-galactopyranose, 2-N-acryloyl-1,3,4,6-tetra-O-acetyl-beta-D-glucosamine, 5-O-acryloyl-2,3-isopropylidene-1-methoxy-beta-D-ribofuranose and 4-N-acetyl-5'-O-acryloyl-2',3'-O-isopropylidene cytidine. Scanning electron microscopy, dynamic light scattering and proton NMR analysis of the emulsions indicated essentially 100% incorporation of the carbohydrate acrylate monomer into the polymer with the exception of O-benzyl- and O-benzoyl-protected carbohydrate acrylates, which gave incomplete incorporation. Formation of larger glyconanoparticles of ~80nm with (unprotected) 3-O-acryloyl-D-glucose and 5-O-acryloyl-1-methoxy-beta-D-ribofuranose revealed the influence of free hydroxyl groups in the monomer on the particle size during polymerization, a feature which is also apparently dependent on the amount of carbohydrate in the matrix. This methodology allows for a new, simple route to the synthesis of polymeric glyconanoparticles with potential applications in targeted drug delivery and materials development. PMID:18677404

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

    PubMed

    McClements, David Julian

    2010-01-01

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

  2. Silicone oil emulsions stabilized by polymers and solid particles.

    PubMed

    Kawaguchi, Masami

    2016-07-01

    Silicone oil emulsions stabilized by various emulsifiers such as polymers, solid particles alone, and solid particles with pre-adsorbed surfactants or polymers are reviewed, focusing on their emulsion stability and rheological properties as a function of the emulsifier concentration. An increase in the concentration of the emulsifier leads to a decrease in the droplet size and an increase in the emulsion stability, irrespective of the emulsifier. Moreover, the overlapping concentration of polymer can be regarded as a criterion for the preparation of emulsions using polymeric emulsifiers. Changes in the emulsion stability and rheological responses of the emulsions prepared by the solid particles with pre-adsorbed polymers are discussed in terms of the amounts of the emulsifiers adsorbed. For emulsions prepared from hydrophilic silica particles with pre-adsorbed polymers, a decrease in the droplet size of an order of magnitude can be controlled by an increase in the concentration of polymer, whereas hydrophilic silica particles alone cannot produce stable silicone oil emulsions. PMID:26170165

  3. 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.

  4. 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 §...

  5. 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 §...

  6. 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 §...

  7. 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 §...

  8. Oilfield solids and water-in-oil emulsion stability.

    PubMed

    Sztukowski, Danuta M; Yarranton, Harvey W

    2005-05-15

    Model water-in-hydrocarbon emulsions consisting of toluene, heptane, water, asphaltenes, and native solids were used to investigate the role of native solids in the stability of oilfield emulsions. The solids were recovered from an oil-sands bitumen, a wellhead emulsion, and a refinery slop oil. The solids were clay platelets and fell into two size categories: (1) fine solids 50 to 500 nm in diameter and (2) coarse solids 1 to 10 microm in diameter. Emulsions stabilized by fine solids and asphaltenes were most stable at a 2:1 fractional area ratio of asphaltenes to solids. It appears that when the asphaltene surface coverage is high, insufficient solids remain to make an effective barrier. When the solids coverage is high, insufficient asphaltenes remain on the interface to immobilize the solids. Treatments that weaken the interface, such as toluene dilution, are recommended for emulsions stabilized by fine solids. Emulsions stabilized by coarse solids were unstable at low solids concentrations but became very stable at solids concentrations greater than 10 kg/m(3). At low concentrations, these solids may act as bridges between water droplets and promote coalescence. At high concentrations, layers of coarse solids may become trapped between water droplets and prevent coalescence. Treatments that flocculate the solids, such as heptane dilution, are recommended for emulsions stabilized by high concentrations of coarse solids. It is possible that emulsions containing both types of solids may require more than one treatment, or even process step, for effective water resolution. PMID:15837502

  9. 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.

  10. 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.

  11. 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

  12. 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...

  13. 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...

  14. 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.

  15. Simulation of Non-Newtonian Emulsion Flows in Microchannels

    NASA Astrophysics Data System (ADS)

    Malanichev, I. V.; Akhmadiev, F. G.

    2015-11-01

    Simulation of emulsion flows in differently shaped microchannels to reproduce the choking of such flows as a result of the effect of dynamic blocking has been made. A model of a highly concentrated emulsion as a structure of tightly packed deformed droplets surrounded by elastic shells is considered. The motion of liquid was determined by the method of the lattice Boltzmann equations together with the immersed boundary method. The influence of the non-Newtonian properties and of elastic turbulence of the indicated emulsion, as well as of the elasticity of the shells of its droplets and of the interaction of these shells on the emulsion motion in a microchannel, has been investigated. It is shown that the flow of this emulsion can be slowed down substantially only due to the mutual attraction of the shells of its droplets.

  16. 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)

  17. [Effect of lipid emulsifiers on the properties of organoperfluorine emulsions].

    PubMed

    Oksinoĭd, O E; Romanova, M Zh; Afonin, N I

    1990-01-01

    The preparation and application of a new type of organoperfluorine (OPF) emulsions with lipids serving as emulsifiers, their biological and physicochemical properties are discussed. The first-generation emulsions with the nonionic emulsifier, ethylene and propylene oxide blockpolymer, were found to be complementary active and to affect the system's biological properties. Interactions between OPF and phospholipids are analysed. The compositions of the new type OPF emulsions are given, of which perfluoroctyl bromide and perfluoromethyl adamantine emulsions are shown to be currently of most interest, since they are stable at room temperature and exhibit somewhat superior physicochemical and biological parameters. A conclusion is derived that the developed lipid-based OPF emulsions have good clinical prospects. PMID:2275276

  18. 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.

  19. Starting a High School Chamber Music Group.

    ERIC Educational Resources Information Center

    Rutkowski, Joseph

    2000-01-01

    Presents ideas on how to begin a chamber music ensemble. Discusses how to find time to accomplish chamber music playing in and around the school day. Presents short descriptions of chamber music that can be used with ensembles. Includes chamber music resources and additional chamber works. (CMK)

  20. Gas and aerosol wall losses in Teflon film smog chambers

    SciTech Connect

    McMurry, P.H.; Grosjean, D.

    1985-12-01

    Large smog chambers (approx.60 m/sup 3/) constructed of FEP Teflon film are frequently used to study photochemistry and aerosol formation in model chemical systems. In a previous paper a theory for aerosol wall loss rates in Teflon film smog chambers was developed; predicted particle loss rates were in good agreement with measured rates. In the present paper, measurements of wall deposition rates and the effects of wall losses on measurements of gas-to-particle conversion in smog chambers are discussed. Calculations indicate that a large fraction of the aerosol formed in several smog chamber experiments was on the chamber walls at the end of the experiment. Estimated values for particulate organic carbon yield for several precursor hydrocarbons increased by factors of 1.3-6.0 when wall deposition was taken into account. The theory is also extended to loss rates of gaseous species. Such loss rates are either limited by diffusion through a concentration boundary layer near the surface or by uptake at the surface. It is shown that for a typical 60-m/sup 3/ Teflon film smog chamber, gas loss rates are limited by surface reaction rates if mass accommodation coefficients are less than 6 x 10/sup -6/. It follows that previously reported loss rates of several gases in a chamber of this type were limited by surface reactions.