WorldWideScience

Sample records for water mass mixing

  1. Neutrinos Mass and Mixing

    CERN Document Server

    González-Garciá, M Concepción

    1998-01-01

    I review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment and the possible role of neutrinos as hot dark matter are also included. I also discuss the simplest schemes proposed to reconcile these data which include a light sterile neutrino in addition to the three standard ones. Implications for future experiments are commented.

  2. Spring 2009 Water Mass Distribution, Mixing and Transport in the Southern Adriatic after a Low Production of Winter Dense Waters

    Science.gov (United States)

    2013-05-21

    the southern Adriatic basin and meets warm and salty Modified Levantine Intermediate Water (MLIW) coming from the Ionian Sea. This study examine...and fresh intermediate water enters the southern Adriatic basin and meets warm and salty Modified Levantine Intermediate Water (MLIW) coming from the...Spring of 2009 can be observed in T–S space (Triangle 2) in Fig. 2. The saltiness of ADW compared to other Adriatic water masses is heavily influenced by

  3. Understanding neutrino masses and mixings

    Indian Academy of Sciences (India)

    R N Mohapatra

    2004-02-01

    We discuss ways to understand large neutrino mixings using new symmetries of quarks and leptons beyond the standard model for the three allowed patterns of neutrino masses: normal, inverted hierarchy and degenerate masses.

  4. Coral Radiocarbon Records of Indian Ocean Water Mass Mixing and Wind-Induced Upwelling Along the Coast of Sumatra, Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T P; Grumet, N S; Abram, N J; Beck, J W; Dunbar, R B; Gagan, M K; Hantoro, W S; Suwargadi, B W

    2004-02-06

    Radiocarbon ({sup 14}C) in the skeletal aragonite of annually banded corals track radiocarbon concentrations in dissolved inorganic carbon (DIC) in surface seawater. As a result of nuclear weapons testing in the 1950s, oceanic uptake of excess {sup 14}C in the atmosphere has increased the contrast between surface and deep ocean {sup 14}C concentrations. We present accelerator mass spectrometric (AMS) measurements of radiocarbon isotope ({Delta}{sup 14}C) in Porites corals from the Mentawai Islands, Sumatra (0 S, 98 E) and Watamu, Kenya (3 S, 39 E) to document the temporal and spatial evolution of the {sup 14}C gradient in the tropical Indian Ocean. The rise in {Delta}{sup 14}C in the Sumatra coral, in response to the maximum in nuclear weapons testing, is delayed by 2-3 years relative to the rise in coral {Delta}{sup 14}C from the coast of Kenya. Kenya coral {Delta}{sup 14}C values rise quickly because surface waters are in prolonged contact with the atmosphere. In contrast, wind-induced upwelling and rapid mixing along the coast of Sumatra entrains {sup 14}C-depleted water from the subsurface, which dilutes the effect of the uptake of bomb-laden {sup 14}C by the surface-ocean. Bimonthly AMS {Delta}{sup 14}C measurements on the Mentawai coral reveal mainly interannual variability with minor seasonal variability. The interannual signal may be a response to changes in the Walker circulation, the development of easterly wind anomalies, shoaling of the eastern thermocline, and upwelling of {sup 14}C-depleted water along the coast of Sumatra. Singular spectrum analysis of the Sumatra coral {Delta}{sup 14}C record reveals a significant 3-year periodicity. The results lend support to the concept that ocean atmosphere interactions between the Pacific and Indian Oceans operate in concert with the El Ni{tilde n}o-Southern Oscillation (ENSO).

  5. Rare earth elements and Nd isotopes tracing water mass mixing and particle-seawater interactions in the SE Atlantic

    Science.gov (United States)

    Garcia-Solsona, E.; Jeandel, C.; Labatut, M.; Lacan, F.; Vance, D.; Chavagnac, V.; Pradoux, C.

    2014-01-01

    Distributions of dissolved and particulate rare earth elements (REEs) and seawater neodymium isotopic composition (εNd) were established in samples from the BONUS GoodHope (BGH) IPY-GEOTRACES cruise in the SE Atlantic sector of the Southern Ocean (36°S-13°E to 57°S-0°, Feb.-Mar. 2008). Close to the South African continent in the subtropical domain, particulate REEs show the highest concentrations and flat PAAS-normalized patterns, clearly tracing their lithogenic origin. Active cerium oxidation onto suspended particles is evidenced by the mirror-image relationship of the cerium anomaly between dissolved and particulate phases. Unradiogenic dissolved neodymium in surface waters (εNd = -17.1) traces the influence of old sedimentary material brought by the Agulhas current and rings to the Cape Basin area. A mass balance calculation suggests that the release of Nd from dissolution of lithogenic material corresponds to a remobilization of 154 × 106 T of sediment per year, i.e., 5% of the total sediment delivered to the southeast African coast annually. At open ocean stations, both dissolved and particulate REEs present negative cerium anomalies, indicating that particles have acquired a marine signature. The increasing REE concentrations with depth, and the strong linear correlations of dissolved REE with silica, indicate that surface removal and deep re-mineralisation of REEs are partially related to the biogeochemical cycle of silicate, which involves biogenic silica (diatoms). Combined with marine carbonates, these authigenic phases could explain the observed REE patterns in suspended particles, except for La. We suggest that the positive La anomalies in both phases are linked to the oceanic barium cycle and the partial dissolution of barite crystals, especially in the Polar Frontal Zone. The εNd composition behaves conservatively in intermediate and deep waters, while input processes affect the isotopic signal of subtropical surface waters and Weddell Gyre

  6. Neutrino Masses and Flavor Mixing

    Science.gov (United States)

    Xing, Zhi-zhong

    2010-06-01

    I give a theoretical overview of some basic properties of massive neutrinos in these lectures. Particular attention is paid to the origin of neutrino masses, the pattern of lepton flavor mixing, the feature of leptonic CP violation and the electromagnetic properties of massive neutrinos. I highlight the TeV seesaw mechanisms as a possible bridge between neutrino physics and collider physics in the era characterized by the Large Hadron Collider.

  7. Nation's water picture mixed

    Science.gov (United States)

    The nation's water picture for April showed mixed trends: More than half of the index gaging stations reported normal streamflow conditions during the month, while the spring snowmelt boosted streamflow in the Northeast and Northwest to well above normal levels. Parts of the Southeast, however, from West Virginia south to the Carolinas, reported well-below normal streamflow conditions, according to a month-end check on water resources conditions by the U.S. Geological Survey, Department of the Interior.After nearly 2 years of drought conditions the three major reservoirs supplying New York City reached full storage capacity and were spilling during April. Combined contents of the three reservoirs on May 1, 1982, was 272 billion gallons, 101% of their full usable capacity. The full reservoirs and the generally good surface and groundwater conditions throughout the Delaware River basin allowed the Delaware River Basin Commission to lift its drought emergency warning on April 27.

  8. Features of Red Sea Water Masses

    KAUST Repository

    Kartadikaria, Aditya R.

    2015-04-01

    Features of Red Sea water mass can be divided into three types but best to be grouped into two different classes that are split at the potential density line σθ=27.4. The surface water (0-50 m) and the intermediate water (50-200 m) have nearly identical types of water mass. They appear as a maxima salinity layer for the water mass that has σθ > 26.0, and as a minimum salinity layer for water mass that has σθ < 26.0. These types of water masses are strongly affected by mixing that is controlled by seasonal variability, fresh water intrusion of the Gulf of Aden Intermediate Water (GAIW), and eddies variability. Two types of mixing; isopycnal and diapycnal mixing are part of important physical phenomena that explain the change of water mass in the Red Sea. The isopycnal mixing occurs at the neutral potential density line, connecting the Red Sea with its adjacent channel, the Gulf of Aden. Diapycnal mixing is found as a dominant mixing mode in the surface of the Red Sea Water and mainly due to energetic eddy activity. Density gradients, across which diapycnal mixing occurs, in the Red Sea are mainly due to large variations in salinity. The isolation of an extreme haline water mass below the thermocline contributes to the generation of the latitudinal shift and low diapycnal mixing. This finding further explains the difference of spatial kinetic mixing between the RSW and the Indian Ocean basin.

  9. Neutrino mass, mixing and discrete symmetries

    CERN Document Server

    Smirnov, Alexei Y

    2013-01-01

    Status of the discrete symmetry approach to explanation of the lepton masses and mixing is summarized in view of recent experimental results, in particular, establishing relatively large 1-3 mixing. The lepton mixing can originate from breaking of discrete flavor symmetry $G_f$ to different residual symmetries $G_{\\ell}$ and $G_\

  10. Supernova constraints on neutrino mass and mixing

    Indian Academy of Sciences (India)

    Srubabati Goswami

    2000-01-01

    In this article I review the constraints on neutrino mass and mixing coming from type-II supernovae. The bounds obtained on these parameters from shock reheating, -process nucleosynthesis and from SN1987A are discussed. Given the current constraints on neutrino mass and mixing the effect of oscillations of neutrinos from a nearby supernova explosion in future detectors will also be discussed.

  11. Theory of neutrino masses and mixing

    CERN Document Server

    Smirnov, Alexei Yu

    2014-01-01

    In spite of enormous experimental progress in determination of the neutrino parameters, theory of neutrino mass and mixing is still on the cross-roads. Guidelines could be (i) the connection between zero neutrino charges (and therefore a possibility to be Majorana particle), smallness of the neutrino mass and large lepton mixing, (ii) joint description of leptons and quarks, (iii) existence of the right handed (RH) neutrinos without special quantum numbers. Properties of the RH neutrinos and the UV completion of the seesaw may turn out to be the key to understand the neutrino mass and mixing. In view of the LHC results minimalistic scenarios like $\

  12. Characterization of Mixing Between Water and Biofuels

    Science.gov (United States)

    Cotel, Aline; Green, Erica; Acevedo, Marina; Otero, Margarita; Demond, Avery

    2012-11-01

    Currently, gasoline containing ethanol is considered to be among the best alternatives to gasoline. However, the potential environmental impact of a spill of ethanol-based biofuels on aquatic environments is an area of open discussion and research. Since these fuels are a combination of a miscible fluid (ethanol) and an immiscible fluid (gasoline), models used for traditional gasoline fuels (immiscible in water) are not applicable. Preliminary experiments show that when a solution of ethanol and glycol is mixed with water, a third mixed fluid is formed. Two distinct mixing regimes were observed. An exothermic reaction also occurred between ethanol and water. In the first regime, a turbulent wake is created between the ethanol/glycol and water layers causing the ethanol and glycol solution to entrain and mix into with the water phase. Because the mixed fluid is denser than either parent fluid, a dramatic overturning is possible. The amount of mixing was found to be dependent upon the initial ratio of ethanol to glycol in the parent fluid. The second regime begins when the turbulent wake has dissipated and the internal wave created by the plate has begun to settle, typically within the first minute. At this point, Bénard-like cells, similar to those typically seen in Rayleigh-Bénard convection, form at the interface and relatively slow mass transfer is evident. The cells at the interface show distinct features of interfacial turbulence, including small transverse waves, denoting that instabilities exist there. Funding from UM-OVPR and NSF Advance.

  13. Neutrino mass, mixing and discrete symmetries

    Science.gov (United States)

    Smirnov, Alexei Y.

    2013-07-01

    Status of the discrete symmetry approach to explanation of the lepton masses and mixing is summarized in view of recent experimental results, in particular, establishing relatively large 1-3 mixing. The lepton mixing can originate from breaking of discrete flavor symmetry Gf to different residual symmetries Gl and Gv in the charged lepton and neutrino sectors. In this framework the symmetry group condition has been derived which allows to get relations between the lepton mixing elements immediately without explicit model building. The condition has been applied to different residual neutrino symmetries Gv. For generic (mass independent) Gv = Z2 the condition leads to two relations between the mixing parameters and fixes one column of the mixing matrix. In the case of Gv = Z2 × Z2 the condition fixes the mixing matrix completely. The non-generic (mass spectrum dependent) Gv lead to relations which include mixing angles, neutrino masses and Majorana phases. The symmetries Gl, Gv, Gf are identified which lead to the experimentally observed values of the mixing angles and allow to predict the CP phase.

  14. Spatial distribution of dissolved neodymium and ɛNd in the Bay of Bengal: Role of particulate matter and mixing of water masses

    Science.gov (United States)

    Singh, Satinder Pal; Singh, Sunil Kumar; Goswami, Vineet; Bhushan, Ravi; Rai, Vinai Kumar

    2012-10-01

    The concentration and isotope composition of dissolved Nd have been measured in the water column along an 87°E transect (GIO1 section of International GEOTRACES Program) in the Bay of Bengal (BoB) to investigate the effect of water mass mixing and Nd release from particulate matter in determining these properties. The concentration of Nd in surface waters of the BoB shows a North-South decreasing non-linear trend (˜46 to ˜22 pmol/kg) with salinity, whereas its depth profiles typically show a high value in surface waters, a minimum (˜15 to ˜23 pmol/kg) in the shallow subsurface (˜50-200 m), followed by a gradual increase with depth. The Nd concentration of BoB waters is generally higher than that in nearby oceanic basins. On the other hand, the ɛNd values in the BoB are less radiogenic compared to those reported for other regions of the global oceans (except Baffin Bay, the North Atlantic Subpolar Gyre and the Niger delta margin), and show a greater variation in the upper water column. Surface waters of the southernmost profile (˜6°N) show a more radiogenic ɛNd value ˜-8, which decreases to -15 in the northernmost profile (˜20°N), close to the values for dissolved and particulate phases of the Ganga-Brahmaputra (G-B) Rivers. This latitudinal trend is most likely a result of variations in mixing proportion between the more radiogenic Indonesian Throughflow surface waters (IW) and unradiogenic BoB low salinity water; the former's signature being more clearly discernible in surface waters of the two southernmost profiles (˜6°N and ˜8.5°N). Attempts to balance the Nd budget in the water column based on an inversion model, suggest that in addition to water masses other source(s) is required, the strength of which is estimated to vary from 1% to 65% of the measured Nd concentration. The calculations also show that the ɛNd of this additional source(s) has to be in the range of ˜-16 ± 2, typical of G-B river sediments. These observations, coupled with

  15. Determination of non-ionic polyethoxylated surfactants in wastewater and river water by mixed hemimicelle extraction and liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Cantero, Manuel; Rubio, Soledad; Pérez-Bendito, Dolores

    2005-03-04

    The capability of hemimicelles-based solid phase extraction (SPE)/liquid chromatography/atmospheric pressure chemical ionisation in positive mode, ion trap mass spectrometry (LC/(APCl+-IT)-MS) for the concentration, separation and quantitation of non-ionic surfactants has been investigated. Concentration was based on the formation of mixed aggregates of analytes [alkylphenol ethoxylates (APE, octyl and nonyl) and alkyl ethoxylates (AE, C12-C16)] with the anionic surfactant sodium dodecyl sulphate (SDS) that is adsorbed on alumina. Parameters affecting SPE were investigated on the basis that hemimicelles are dynamic entities in equilibrium with the aqueous phase. The performance of ion trap mass spectrometry for MS and MS/MS quantitation of non-ionic homologues was assessed. Recoveries of analytes from wastewater influent and effluent and river water samples ranged between 91 and 98% and were found independent on the length of the alkyl chain under the optimised conditions. Anionic surfactants did not interfere to the levels found in environmental samples. The detection limits ranged between 14 and 111 ng/l for wastewater influent, 10 and 40 for wastewater effluent and 4 and 35 for river water, after concentration of 250, 500 and 750 ml of sample, respectively. The approach was applied to the determination of AE and APE in influent and effluent samples from four wastewater treatment plants and four river samples. The concentrations of individual non-ionic surfactants found ranged between 0.3 and 373 microg/l.

  16. Measurement of low-ppm mixing ratios of water vapor in the upper troposphere and lower stratosphere using chemical ionization mass spectrometry

    Directory of Open Access Journals (Sweden)

    T. D. Thornberry

    2013-06-01

    Full Text Available A chemical ionization mass spectrometer (CIMS instrument has been developed for the fast, precise, and accurate measurement of water vapor (H2O at low mixing ratios in the upper troposphere and lower stratosphere (UT/LS. A low-pressure flow of sample air passes through an ionization volume containing an α-particle radiation source, resulting in a cascade of ion-molecule reactions that produce hydronium ions (H3O+ from ambient H2O. The production of H3O+ ions from ambient H2O depends on pressure and flow through the ion source, which were tightly controlled in order to maintain the measurement sensitivity independent of changes in the airborne sampling environment. The instrument was calibrated every 45 min in flight by introducing a series of H2O mixing ratios between 0.5 and 153 parts per million (ppm, 10−6 mol mol−1 generated by Pt-catalyzed oxidation of H2 standards while overflowing the inlet with dry synthetic air. The CIMS H2O instrument was deployed in an unpressurized payload area aboard the NASA WB-57F high-altitude research aircraft during the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX mission in March and April 2011. The instrument performed successfully during seven flights, measuring H2O mixing ratios below 5 ppm in the lower stratosphere at altitudes up to 17.7 km, and as low as 3.5 ppm near the tropopause. Data were acquired at 10 Hz and reported as 1 s averages. In-flight calibrations demonstrated a typical sensitivity of 2000 Hz ppm−1 at 3 ppm with a signal to noise ratio (2 σ, 1 s greater than 32. The total measurement uncertainty was 9 to 11%, derived from the uncertainty in the in situ calibrations.

  17. Neutrino masses and mixing in supersymmetric theories

    Indian Academy of Sciences (India)

    Sudhir K Vempati

    2000-07-01

    It has been known for sometime that supersymmetric theories with -parity violation provide a natural framework where small neutrino masses can be generated. We discuss neutrino masses and mixing in these theories in the presence of trilinear lepton number violating couplings. It will be shown that simultaneous solutions to solar and atmospheric neutrino problems can be realized in these models.

  18. Selective determination of antimycotic drugs in environmental water samples by mixed-mode solid-phase extraction and liquid chromatography quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Casado, J; Rodríguez, I; Ramil, M; Cela, R

    2014-04-25

    The suitability of mixed-mode (reversed-phase and cationic exchange) solid-phase extraction (SPE) for the selective concentration of basic antimycotic drugs (belonging to triazole, imidazole and allylamine chemical classes) in environmental water samples has been demonstrated for first time. The use of a sequential elution protocol, allowing the removal of neutral and acidic interferences before analytes extraction, led to a significant reduction of matrix effects, during electrospray ionization (ESI), in comparison with results reported for reversed-phase sorbents. In combination with liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS) determination, the developed method attained limits of quantification (LOQs) comprised between 2 and 15ngL(-1). After internal surrogate correction, accurate results (in most cases, recoveries ranged between 75 and 117%) were obtained for spiked aliquots of raw and treated wastewater, as well as river water, using quantification against calibration standard solutions in methanol (2% in NH3). Accurate, scan MS/MS spectra allowed the unambiguous identification of target compounds in environmental samples; furthermore, the information contained in MS spectra was used for the screening of additional antimycotics in the processed samples. Fluconazole, ketoconazole, miconazole and clotrimazole were measured in wastewater samples at concentrations up to 200ngL(-1). The screening capabilities of the LC-QTOF-MS system permitted to identify the systematic presence of climbazole in the processed samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Analysis of linear alkylbenzene sulfonate homologues in environmental water samples by mixed admicelle-based extraction and liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Lunar, Loreto; Rubio, Soledad; Pérez-Bendito, Dolores

    2006-07-01

    Hemimicelles and admicelles of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), adsorbed onto silica, were tested as sorbents for the solid phase extraction (SPE) of linear alkylbenzene sulfonate (LAS) homologues from environmental water samples. LASs were quantitatively retained on both surfactants due to high hydrophobic and ionic interactions, which led to the formation of analyte-extractant mixed aggregates. Parameters affecting the SPE of LASs were optimised. Recoveries of analytes from wastewater influent and effluent and river water samples ranged between 86 and 110%. Combination of SPE with liquid chromatography/mass spectrometry provided detection limits for the different LAS homologues of about 4 ng L(-1). The precision of the method, expressed as relative standard deviation, ranged from 5 to 9%. The method was applied to the analysis of LASs in wastewater and river samples using sample volumes between 10 and 25 mL. The LAS concentrations found ranged from 9 to 503 microg L(-1). No cleaning step was required to get accurate results.

  20. Mixing and Mass Transfer in Industrial Bioreactors

    DEFF Research Database (Denmark)

    Villadsen, John

    2015-01-01

    becomes an important issue, and from mixing time as a function of the geometry of the reactor and the power input, one derives expressions for the transfer parameters. This chapter collects the most important empirical knowledge about design of mixers to achieve a particular goal. The resulting design......Design of a real reactor for a real process in industrial scale requires much more than the design of the "ideal" reactors. This insight is formulated in empirical relations between key process parameters, such as mass and heat transfer coefficients, and the power input to the process. Mixing...

  1. Neutrino Mass and Mixing with Discrete Symmetry

    CERN Document Server

    King, Stephen F

    2013-01-01

    This is a review article about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of seesaw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mec...

  2. Higgs mass from neutrino-messenger mixing

    CERN Document Server

    Byakti, Pritibhajan; Mummidi, V Suryanarayana; Vempati, Sudhir K

    2016-01-01

    The discovery of the Higgs particle at 125 GeV has put strong constraints on minimal messenger models of gauge mediation, pushing the stop masses into the multi-TeV regime. Extensions of these models with matter-messenger mixing terms have been proposed to generate a large trilinear parameter, $A_t$, relaxing these constraints. The detailed survey of these models \\cite{Byakti:2013ti,Evans:2013kxa} so far considered messenger mixings with only MSSM superfields. In the present work, we extend the survey to MSSM with inverse-seesaw mechanism. The neutrino-sneutrino corrections to the Higgs mass in the inverse seesaw model are not significant in the minimal gauge mediation model, unless one considers messenger-matter interaction terms. We classify all possible models with messenger-matter interactions and perform thorough numerical analysis to find out the promising models. We found that out of the 17 possible models 15 of them can lead to Higgs mass within the observed value without raising the sfermion masses s...

  3. Quark flavor mixings from hierarchical mass matrices

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Rohit [Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China); Rayat Institute of Engineering and Information Technology, Ropar (India); Zhou, Shun [Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China); Peking University, Center for High Energy Physics, Beijing (China)

    2016-05-15

    In this paper, we extend the Fritzsch ansatz of quark mass matrices while retaining their hierarchical structures and show that the main features of the Cabibbo-Kobayashi-Maskawa (CKM) matrix V, including vertical stroke V{sub us} vertical stroke ≅ vertical stroke V{sub cd} vertical stroke, vertical stroke V{sub cb} vertical stroke ≅ vertical stroke V{sub ts} vertical stroke and vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke < vertical stroke V{sub td} vertical stroke / vertical stroke V{sub ts} vertical stroke can be well understood. This agreement is observed especially when the mass matrices have non-vanishing (1, 3) and (3, 1) off-diagonal elements. The phenomenological consequences of these for the allowed texture content and gross structural features of 'hierarchical' quark mass matrices are addressed from a model-independent prospective under the assumption of factorizable phases in these. The approximate and analytical expressions of the CKM matrix elements are derived and a detailed analysis reveals that such structures are in good agreement with the observed quark flavor mixing angles and the CP-violating phase at the 1σ level and call upon a further investigation of the realization of these structures from a top-down prospective. (orig.)

  4. Water masses in the Gulf of Aden

    Digital Repository Service at National Institute of Oceanography (India)

    Al Saafani, M.A.; Shenoi, S.S.C.

    (1981a and b). The method is an extension of the mixing triangle theory. Conserving the mass, the relative contribution of any water mass to the water sample at a location can be determined from the linear system of equations given as AX = B where A...-salinity values in the west are very different from those in the east. Hence, to assess the quality of the profiles, the monthly means and standard deviations were computed at each depth level separately in 20 longitude x 20 latitude bins. Values...

  5. Neutrino masses from an approximate mixing matrix with $\\theta_{13}\

    CERN Document Server

    Damanik, Asan

    2016-01-01

    An approximate neutrino mixing matrix is formutated by using the standard neutrino mixing matrix as a basis and experimental data of neutrino oscillations as inputs. By using the resulted approximate neutrino mixing matrix to proceed the neutrino mass matrix and constraining the resulted neutrino mass matrix with zero texture: $M_{\

  6. Variable viscosity effects on mixed convection heat and mass ...

    African Journals Online (AJOL)

    Variable viscosity effects on mixed convection heat and mass transfer along a ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Keywords: Variable viscosity, Chemical Reaction, Viscous Dissipation, Finite difference method, Suction.

  7. Synergistic, ultrafast mass storage and removal in artificial mixed conductors

    Science.gov (United States)

    Chen, Chia-Chin; Fu, Lijun; Maier, Joachim

    2016-08-01

    Mixed conductors—single phases that conduct electronically and ionically—enable stoichiometric variations in a material and, therefore, mass storage and redistribution, for example, in battery electrodes. We have considered how such properties may be achieved synergistically in solid two-phase systems, forming artificial mixed conductors. Previously investigated composites suffered from poor kinetics and did not allow for a clear determination of such stoichiometric variations. Here we show, using electrochemical and chemical methods, that a melt-processed composite of the ‘super-ionic’ conductor RbAg4I5 and the electronic conductor graphite exhibits both a remarkable silver excess and a silver deficiency, similar to those found in single-phase mixed conductors, even though such behaviour is not possible in the individual phases. Furthermore, the kinetics of silver uptake and release is very fast. Evaluating the upper limit set by interfacial ambipolar diffusion reveals chemical diffusion coefficients that are even higher than those achieved for sodium chloride in bulk liquid water. These results could potentially stimulate systematic research into powerful, even mesoscopic, artificial mixed conductors.

  8. Relating masses and mixing angles. A model-independent model

    Energy Technology Data Exchange (ETDEWEB)

    Hollik, Wolfgang Gregor [DESY, Hamburg (Germany); Saldana-Salazar, Ulises Jesus [CINVESTAV (Mexico)

    2016-07-01

    In general, mixing angles and fermion masses are seen to be independent parameters of the Standard Model. However, exploiting the observed hierarchy in the masses, it is viable to construct the mixing matrices for both quarks and leptons in terms of the corresponding mass ratios only. A closer view on the symmetry properties leads to potential realizations of that approach in extensions of the Standard Model. We discuss the application in the context of flavored multi-Higgs models.

  9. Mixed-mode solid-phase extraction coupled with liquid chromatography tandem mass spectrometry to determine phenoxy acid, sulfonylurea, triazine and other selected herbicides at nanogram per litre levels in environmental waters.

    Science.gov (United States)

    Zhang, Pei; Bui, Anhduyen; Rose, Gavin; Allinson, Graeme

    2014-01-17

    The method presented uses a mixed-mode anion exchange SPE and liquid chromatography tandem mass spectrometry to analyze 5 sulfonylurea, 8 phenoxy acid, 12 triazine and 6 other herbicides in environmental waters. The mixed-mode SPE cartridge is able to retain a wide range of herbicides with acidic-neutral-basic characteristics, particularly the highly polar and acidic compounds clopyralid, dicamba and picloram. The neutral and basic herbicides can be effectively eluted with methanol, after which the acidic herbicides can be eluted using acidified methanol. The method has achieved an LOD of 0.7-3ng/L for the sulfonylureas, 4-12ng/L for the phenoxy acids and 0.4-30ng/L for the triazine and additional herbicides, with recoveries in the range 76-107%, 73-126%, and 65-104%, respectively. The precision of the method, calculated as relative standard deviation (RSD), was below 10% for both sulfonylurea and phenoxy acid herbicides, and less than 20% for the remaining herbicides. The developed method was used to determine the concentration of target herbicides in a range of environmental waters, and many of the target herbicides were detected at ng/L level.

  10. Hierarchical neutrino masses and mixing in flipped-SU(5)

    Energy Technology Data Exchange (ETDEWEB)

    Rizos, J. [Physics Department, University of Ioannina, 45110 Ioannina (Greece); Tamvakis, K., E-mail: tamvakis@uoi.g [Physics Department, University of Ioannina, 45110 Ioannina (Greece); Physics Department, CERN, CH-1211, Geneva 23 (Switzerland)

    2010-02-22

    We consider the problem of neutrino masses and mixing in the framework of flipped SU(5). The right-handed neutrino mass, generated through the operation of a seesaw mechanism by a sector of gauge singlets, leads naturally, at a subsequent level, to the standard seesaw mechanism resulting into three light neutrino states with masses of the desired phenomenological order of magnitude. In this framework we study simple Ansaetze for the singlet couplings for which hierarchical neutrino masses emerge naturally as lambda{sup n}:lambda:1 or lambda{sup n}:lambda{sup 2}:1, parametrized in terms of the Cabbibo parameter. The resulting neutrino mixing matrices are characterized by a hierarchical structure, in which theta{sub 13} is always predicted to be the smallest. Finally, we discuss a possible factorized parametrization of the neutrino mass that, in addition to Cabbibo mixing, encodes also mixing due to the singlet sector.

  11. Fermion masses as mixing parameters in the SM

    CERN Document Server

    Saldaña-Salazar, U J

    2016-01-01

    Flavor transitions via the charged current interactions are parametrized by a three dimensional and unitary transformation. This so called mixing matrix requires of four mixing parameters. Here we show that under the phenomenological observation of hierarchical fermion masses, $m_3 \\gg m_2 \\gg m_1$, a mixing parametrization can be built with its mixing parameters being the corresponding four independent mass ratios of each fermion sector, i.e., $m_u/m_c$, $m_c/m_t$, $m_d/m_s$, and $m_s/m_b$ and $m_e/m_\\mu$, $m_\\mu/m_\\tau$, $m_{\

  12. Radiative generation of neutrino mixing: degenerate masses and threshold corrections

    CERN Document Server

    Hollik, Wolfgang Gregor

    2014-01-01

    Degenerate neutrino masses are excluded by experiment. The experimentally measured mass squared differences together with the yet undetermined absolute neutrino mass scale allow for a quasi-degenerate mass spectrum. For the lightest neutrino mass larger than roughly 0.1 eV, we analyse the influence of threshold corrections at the electroweak scale. We show that typical one-loop corrections can generate the observed neutrino mixing as well as the mass differences starting from exactly degenerate masses at the tree-level. Those threshold corrections have to be explicitly flavour violating. Flavour diagonal, non-universal corrections are not sufficient to simultaneously generate the correct mixing and the mass differences. We apply the new insights to an extension of the Minimal Supersymmetric Standard Model with non-minimal flavour violation in the soft breaking terms and discuss the low-energy threshold corrections to the light neutrino mass matrix in that model.

  13. Reactor mixing angle from hybrid neutrino masses

    CERN Document Server

    Sierra, D Aristizabal

    2014-01-01

    In terms of its eigenvector decomposition, the neutrino mass matrix (in the basis where the charged lepton mass matrix is diagonal) can be understood as originating from a tribimaximal dominant structure with small deviations, as demanded by data. If neutrino masses originate from at least two different mechanisms, referred to as "hybrid neutrino masses", the experimentally observed structure naturally emerges provided one mechanism accounts for the dominant tribimaximal structure while the other is responsible for the deviations. We demonstrate the feasibility of this picture in a fairly model-independent way by using lepton-number-violating effective operators, whose structure we assume becomes dictated by an underlying $A_4$ flavor symmetry. We show that if a second mechanism is at work, the requirement of generating a reactor angle within its experimental range always fixes the solar and atmospheric angles in agreement with data, in contrast to the case where the deviations are induced by next-to-leading ...

  14. Dynamical fermion mass hierarchy and flavour mixing

    Energy Technology Data Exchange (ETDEWEB)

    Luest, D.; Papantonopoulos, E.; Zoupanos, G.

    1984-08-01

    The chiral symmetry breaking of high colour representations produces dynamical breaking of the standard electroweak gauge symmetry. By enlarging the colour group and subsequently breaking it down to SU(3)sub(c) fermions acquire radiative masses from the chiral breaking. We present attempts to produce realistic fermion mass matrix in two classes of models depending on the way that the colour group is enlarged. A realistic example is found in one of these classes of models.

  15. Marketing mix of chosen Slovak mineral water

    Directory of Open Access Journals (Sweden)

    Juhanová Silvia

    2001-09-01

    Full Text Available Considering its small area, Slovakia abounds in many sources of mineral waters and a considerable amount of them can be used for the commercial utilization. STN 86 8000 divides mineral waters in the natural mineral waters, natural mineral table waters and the natural mineral healing waters. Natural mineral water is, after the present norm, in effect water, which rises from natural trapped sources. This type of water contains more than 1 gram of dissolved substances or 1 gram of dissolved CO 2 in 1 litter. Natural mineral table water is water that, with its chemical composition as well as its physical and sensorial attributes is suitable as a refresher. It contains at least 1 gram of melted CO2 and up to 6 grams of dissolved illiquid substances in 1 litter. The mentioned substances are not characterised by any marked pharmacological effect. Natural mineral healing water is water, which with an eye to its chemical composition and physical properties, have a scientifically demonstrable effects to the human health and it is generally used for healing purposes. In the present contribution, an attention is orientated to the occurrence of listed types of waters in Slovakia, in connection with geological conditions of their circulation and accumulation and especially with possibilities of their use on the Slovak buyer’s market.The marketing mix is a complex of information, which can be regulated. Firms accumulate this information to satisfy a customer. Marketing mix of mineral waters includes information about four variables: product (characteristics of product, quality, packing, design..., prices, advertisement, distribution (the way how to get product to customer. Data listed in the contribution come from the sectional market research, which was performed between December 1st and December 22nd 2000 in twenty groceries in

  16. Tidal mixing in Dahej creek waters

    Digital Repository Service at National Institute of Oceanography (India)

    Swamy, G.N.; Sarma, R.V.

    Mixing characteristics of a tidal inlet near Dahej at the mouth of Narmada River, Gujarat, India are examined in terms of tides, currents and bathymetry. The dilution potential of the Dahej Creek waters during a tidal march for a given rate...

  17. Theory of Neutrino Masses and Mixing

    CERN Document Server

    Grimus, Walter

    2011-01-01

    We motivate the usage of finite groups as symmetries of the Lagrangian. After a presentation of basic group-theoretical concepts, we introduce the notion of characters and character tables in the context of irreducible representations and discuss their applications. We exemplify these theoretical concepts with the groups S_4 and A_4. Finally, we discuss the relation between tensor products of irreducible representations and Yukawa couplings and describe a model for tri-bimaximal lepton mixing based on A_4.

  18. Models of neutrino mass, mixing and CP violation

    Science.gov (United States)

    King, Stephen F.

    2015-12-01

    In this topical review we argue that neutrino mass and mixing data motivates extending the Standard Model (SM) to include a non-Abelian discrete flavour symmetry in order to accurately predict the large leptonic mixing angles and {C}{P} violation. We begin with an overview of the SM puzzles, followed by a description of some classic lepton mixing patterns. Lepton mixing may be regarded as a deviation from tri-bimaximal mixing, with charged lepton corrections leading to solar mixing sum rules, or tri-maximal lepton mixing leading to atmospheric mixing rules. We survey neutrino mass models, using a roadmap based on the open questions in neutrino physics. We then focus on the seesaw mechanism with right-handed neutrinos, where sequential dominance (SD) can account for large lepton mixing angles and {C}{P} violation, with precise predictions emerging from constrained SD (CSD). We define the flavour problem and discuss progress towards a theory of favour using GUTs and discrete family symmetry. We classify models as direct, semidirect or indirect, according to the relation between the Klein symmetry of the mass matrices and the discrete family symmetry, in all cases focussing on spontaneous {C}{P} violation. Finally we give two examples of realistic and highly predictive indirect models with CSD, namely an A to Z of flavour with Pati-Salam and a fairly complete A 4 × SU(5) SUSY GUT of flavour, where both models have interesting implications for leptogenesis.

  19. Neutrino mass and mixing – status

    Indian Academy of Sciences (India)

    Thomas Schwetz

    2012-11-01

    The status of neutrino oscillations from global data are summarized. An update on the three-flavour picture and recent developments are discussed with regard to the measurement of the mixing angle 13. Global data currently provide an indication at 3 that 13 is non-zero. Furthermore, the status of sterile neutrino oscillation interpretations of the LSND anomaly in the light of MiniBooNE results and a recent re-evaluation of the neutrino fluxes from nuclear reactors are discussed. Despite several hints for sterile neutrinos at the eV scale, there is severe tension in the global data and no consistent description of all data is possible.

  20. A Model of Quark and Lepton Mixing and Mass Hierarchy

    CERN Document Server

    Barr, S M

    2015-01-01

    It is shown that an idea proposed in 1996 that relates in a qualitatively correct way the inter-family mass hierarchies of the up quarks, down quarks, charged leptons, and neutrinos, can be combined with a predictive scheme recently proposed for relating quark mixing and neutrino mixing. In the resulting model, the entire flavor structure of the quarks and leptons is expressible in terms of two "master matrices": a diagonal matrix that gives the inter-family mass ratios, and an off-diagonal matrix that controls all flavor mixing.

  1. Higgs-boson masses and mixing matrices in the NMSSM

    DEFF Research Database (Denmark)

    Drechsel, P.; Gröber, R.; Heinemeyer, S.

    2017-01-01

    We analyze the Higgs-boson masses and mixing matrices in the NMSSM based on an on-shell (OS) renormalization of the gauge-boson and Higgs-boson masses and the parameters of the top/scalar top sector. We compare the implementation of the OS calculations in the codes NMSSMCALC and NMSSM-FeynHiggs up...

  2. Models of Neutrino Mass, Mixing and CP Violation

    CERN Document Server

    King, Stephen F

    2015-01-01

    In this topical review we argue that neutrino mass and mixing data motivates extending the Standard Model to include a non-Abelian discrete flavour symmetry in order to accurately predict the large leptonic mixing angles and CP violation. We begin with an overview of the Standard Model puzzles, followed by a description of some classic lepton mixing patterns. Lepton mixing may be regarded as a deviation from tri-bimaximal mixing, with charged lepton corrections leading to solar mixing sum rules, or tri-maximal lepton mixing leading to atmospheric mixing rules. We survey neutrino mass models, using a roadmap based on the open questions in neutrino physics. We then focus on the seesaw mechanism with right-handed neutrinos, where sequential dominance (SD) can account for large lepton mixing angles and CP violation, with precise predictions emerging from constrained SD (CSD). We define the flavour problem and discuss progress towards a theory of flavour using GUTs and discrete family symmetry. We classify models ...

  3. Fermion Masses and Mixing in Four and More Dimensions

    CERN Document Server

    Chamoun, N

    2005-01-01

    We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. Mass matrix ansatze are considered within the SM and SUSY GUTs where some predictive frameworks based on SU(5) and SO(10) are reviewed. We describe a variety of schemes to construct quark mass matrices in extra dimensions focusing on four major classes: models with the SM residing on 3-brane, models with universal extra dimensions, models with split fermions and models with warped extra dimensions. We outline how realistic patterns of quark mass matrices could be derived from orbifold models in heterotic superstring theory. Finally, we address the fermion mass problem in intersecting D-branes scenarios, and present models with D6-branes able to give a good quantitatively description of quark masses and mixing. The role of flavor/CP violation problem as a probe of new physics is emphasized.

  4. Fermion masses and mixing in $\\Delta(27)$ flavour model

    CERN Document Server

    Abbas, Mohammed

    2014-01-01

    An extension of the Standard Model (SM) based on the non-Abelian discrete group $\\Delta(27)$ is considered. The $\\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any flavour changing neural current. We show that the model accounts simultaneously for the observed quark and lepton masses and their mixing. In the quark sector, we find that the up quark mass matrix is flavour diagonal and the Cabbibo-Kobayashi-Maskawa (CKM) mixing matrix arises from down quarks. In the lepton sector, we show that the charged lepton mass matrix is almost diagonal. We also adopt type-I seesaw mechanism to generate neutrino masses. A deviated mixing matrix from tri-bimaximal Maki-Nakagawa-Sakata (MNS), with $\\sin\\theta_{13} \\sim 0.13$ and $\\sin^2 \\theta_{23} \\sim 0.41$, is naturally produced.

  5. Organic aerosol mixing observed by single-particle mass spectrometry.

    Science.gov (United States)

    Robinson, Ellis Shipley; Saleh, Rawad; Donahue, Neil M

    2013-12-27

    We present direct measurements of mixing between separately prepared organic aerosol populations in a smog chamber using single-particle mass spectra from the high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Docosane and docosane-d46 (22 carbon linear solid alkane) did not show any signs of mixing, but squalane and squalane-d62 (30 carbon branched liquid alkane) mixed on the time scale expected from a condensational-mixing model. Docosane and docosane-d46 were driven to mix when the chamber temperature was elevated above the melting point for docosane. Docosane vapors were shown to mix into squalane-d62, but not the other way around. These results are consistent with low diffusivity in the solid phase of docosane particles. We performed mixing experiments on secondary organic aerosol (SOA) surrogate systems finding that SOA derived from toluene-d8 (a surrogate for anthropogenic SOA (aSOA)) does not mix into squalane (a surrogate for hydrophobic primary organic aerosol (POA)) but does mix into SOA derived from α-pinene (biogenic SOA (bSOA) surrogate). For the aSOA/POA, the volatility of either aerosol does not limit gas-phase diffusion, indicating that the two particle populations do not mix simply because they are immiscible. In the aSOA/bSOA system, the presence of toluene-d8-derived SOA molecules in the α-pinene-derived SOA provides evidence that the diffusion coefficient in α-pinene-derived SOA is high enough for mixing on the time scale of 1 min. The observations from all of these mixing experiments are generally invisible to bulk aerosol composition measurements but are made possible with single-particle composition data.

  6. Coolant mixing in pressurized water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hoehne, T.; Grunwald, G.

    1998-10-01

    The behavior of PWRs during cold water or boron dilution transients is strongly influenced by the distribution of coolant temperature and boron concentration at the core inlet. This distribution is the needed input to 3-dimensional neutron kinetics to calculate the power distribution in the core. It mainly depends on how the plugs of cold or unborated water formed in a single loop are mixed in the downcomer and in the lower plenum. To simulate such mixture phenomena requires the application of 3-dimensional CFD (computational fluid dynamics) codes. The results of the simulation have to be validated against mixture experiments at scaled facilities. Therefore, in the framework of a research project funded by BMBF, the institute creates a 1:5 mixture facility representing first the geometry of a German pressurized water reactor and later the European Pressurized Water Reactor (EPR) geometry. The calculations are based on the CFD Code CFX-4. (orig.)

  7. Neutrino mass and mixing in the seesaw playground

    Energy Technology Data Exchange (ETDEWEB)

    King, Stephen F., E-mail: king@soton.ac.uk

    2016-07-15

    We discuss neutrino mass and mixing in the framework of the classic seesaw mechanism, involving right-handed neutrinos with large Majorana masses, which provides an appealing way to understand the smallness of neutrino masses. However, with many input parameters, the seesaw mechanism is in general not predictive. We focus on natural implementations of the seesaw mechanism, in which large cancellations do not occur, where one of the right-handed neutrinos is dominantly responsible for the atmospheric neutrino mass, while a second right-handed neutrino accounts for the solar neutrino mass, leading to an effective two right-handed neutrino model. We discuss recent attempts to predict lepton mixing and CP violation within such natural frameworks, focusing on the Littlest Seesaw and its distinctive predictions.

  8. Neutrino masses and mixing from S4 flavor twisting

    CERN Document Server

    Ishimori, Hajime; Tanimoto, Morimitsu; Watanabe, Atsushi

    2010-01-01

    We discuss a neutrino mass model based on the S4 discrete symmetry where the symmetry breaking is triggered by the boundary conditions of the bulk right-handed neutrino in the fifth spacial dimension. While the symmetry restricts bare mass parameters to flavor-diagonal forms, the viable mixing angles emerge from the wave functions of the Kaluza-Klein modes which carry symmetry breaking effect. The magnitudes of the lepton mixing angles, especially the reactor angle is related to the neutrino mass patterns and the model will be tested in future neutrino experiments, e.g., an early (late) discovery of the reactor angle favors the normal (inverted) hierarchy. The size of extra dimension has a connection to the possible mass spectrum; a small (large) volume corresponds to the normal (inverted) mass hierarchy.

  9. Neutrino mass and mixing in the seesaw playground

    Science.gov (United States)

    King, Stephen F.

    2016-07-01

    We discuss neutrino mass and mixing in the framework of the classic seesaw mechanism, involving right-handed neutrinos with large Majorana masses, which provides an appealing way to understand the smallness of neutrino masses. However, with many input parameters, the seesaw mechanism is in general not predictive. We focus on natural implementations of the seesaw mechanism, in which large cancellations do not occur, where one of the right-handed neutrinos is dominantly responsible for the atmospheric neutrino mass, while a second right-handed neutrino accounts for the solar neutrino mass, leading to an effective two right-handed neutrino model. We discuss recent attempts to predict lepton mixing and CP violation within such natural frameworks, focusing on the Littlest Seesaw and its distinctive predictions.

  10. Neutrino Masses and Mixing one Decade from Now

    CERN Document Server

    González-Garciá, M Concepción

    2000-01-01

    We review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment is also considered. We discuss the present knowledge and the expected sensitivity to the neutrino mixing parameters in the simplest schemes proposed to reconcile these data some of which include a light sterile neutrino in addition to the three standard ones.

  11. A Probability Density Function for Neutrino Masses and Mixings

    CERN Document Server

    Fortin, Jean-François; Marleau, Luc

    2016-01-01

    The anarchy principle leading to the see-saw ensemble is studied analytically with the usual tools of random matrix theory. The probability density function for the see-saw ensemble of $N\\times N$ matrices is obtained in terms of a multidimensional integral. This integral involves all light neutrino masses, leading to a complicated probability density function. It is shown that the probability density function for the neutrino mixing angles and phases is the appropriate Haar measure. The decoupling of the light neutrino masses and neutrino mixings implies no correlation between the neutrino mass eigenstates and the neutrino mixing matrix, in contradiction with observations but in agreement with some of the claims found in the literature.

  12. Probability density function for neutrino masses and mixings

    Science.gov (United States)

    Fortin, Jean-François; Giasson, Nicolas; Marleau, Luc

    2016-12-01

    The anarchy principle leading to the seesaw ensemble is studied analytically with the usual tools of random matrix theory. The probability density function for the seesaw ensemble of N ×N matrices is obtained in terms of a multidimensional integral. This integral involves all light neutrino masses, leading to a complicated probability density function. It is shown that the probability density function for the neutrino mixing angles and phases is the appropriate Haar measure. The decoupling of the light neutrino masses and neutrino mixings implies no correlation between the neutrino mass eigenstates and the neutrino mixing matrix and leads to a loss of predictive power when comparing with observations. This decoupling is in agreement with some of the claims found in the literature.

  13. New supersymmetric source of neutrino masses and mixings

    CERN Document Server

    Casas, J A; Navarro, I

    2002-01-01

    Conventionally, neutrino masses in a supersymmetric theory arise from non-renormalizable lepton-number (L)-violating operators in the superpotential. The alternative possibility of having such operators in the Kahler potential as the dominant source of neutrino masses has very interesting implications and differences with respect to the standard scenario: first, the scale of L-violation can be lowered dramatically and neutrino masses have a different tan beta-dependence; second, the renormalization of these operators has remarkable properties: in many cases it improves drastically the stability of neutrino textures against radiative corrections, while in others it makes possible to generate radiatively large mixing angles in a natural way. In particular, the mass splitting and mixing angle of solar neutrinos (LAMSW solution) can be explained as a purely radiative effect.

  14. Quark masses and mixings with hierarchical Friedberg-Lee symmetry

    Science.gov (United States)

    Araki, Takeshi; Geng, C. Q.

    2010-04-01

    We consider the Friedberg-Lee symmetry for the quark sector and show that the symmetry closely relates to both quark masses and mixing angles. We also extend our scheme to the fourth generation quark model and find the relation |Vtb'|≃|Vt'b|≃mb/mb'199GeV.

  15. Quark Masses and Mixings with Hierarchical Friedberg-Lee Symmetry

    CERN Document Server

    Araki, T

    2010-01-01

    We propose the hierarchically translating Friedberg-Lee (FL) symmetry for the quark sector and show that the symmetry closely relates to both quark masses and mixings angles. We also extend our scheme to the fourth generation quark model and find the relation $|V_{tb^{'}}| \\simeq |V_{t^{'}b}| \\simeq m_b/m_{b^{'}}199 \\gev$.

  16. Rho-. omega. mixing and the n-p mass difference

    Energy Technology Data Exchange (ETDEWEB)

    Epele, L.N.; Fanchiotti, H.; Garci Canal, C.A.; Mendez Galain, R.

    1989-03-01

    rho-..omega.. mixing, a nonelectromagnetic isospin violation, is shown to be able to account for the neutron-proton mass difference. The analysis is done in the framework of the SU(2) Skyrme model and the result is in good agreement with experimental data.

  17. Applying rotary jet heads for mixing and mass transfer in a forced recirculation tank reactor system

    DEFF Research Database (Denmark)

    Nordkvist, Mikkel; Grotkjær, Thomas; Hummer, J.S.

    2003-01-01

    An approximation to an ideally mixed tank reactor can be obtained by vigorous stirring with mechanical mixers. For an aerated reactor the gas dispersion contributes to the mixing process. Mixing can also be achieved by recirculation of a portion of the liquid through either an internal...... or an external loop.In this study, we determine mixing times in water and CMC solutions and oxygen mass transfer coefficients in water for a tank reactor system where a small fraction of the total liquid volume is rapidly circulated through an external loop and injected through the nozzles of rotary jet heads...... at 1-9 bar gauge pressure into the bulk liquid. Liquid feed can be added to the bulk volume or it may be injected into the pressurized recirculation loop. Gas is always fed to the recirculation loop, and the heat of reaction is removed in a plate-type heat exchanger inserted in the recirculation loop...

  18. New Methods of Fitting the Membership Function of Oceanic Water Masses

    Institute of Scientific and Technical Information of China (English)

    LI Fengqi; XIE Jun; LI Yao

    2004-01-01

    After reviewing the analytical theories of T-S curve, some methods of T-S relationship, and fuzzy sets for studying water masses, new methods of fitting the membership function of oceanic water masses are presented based on the characteristics of T-S curve family of oceanic water masses. The membership functions of oceanic Subsurface Water Mass with high salinity and Intermediate Water Mass with low salinity are fitted and discussed using the new methods. The proposed methods are useful in analyzing the mixing and modifying processes of these water masses, especially in tracing their sources.The principles and formulae of the new methods and examples are given.

  19. Refrigerating machine operating characteristics under various mixed refrigerant mass charges

    Energy Technology Data Exchange (ETDEWEB)

    Rozhentsev, Andrey [Far Eastern State Transport University of the Russian Federation, Seryshev street, 47, 680021 Khabarovsk (Russian Federation)

    2008-11-15

    This paper reports the results of experimental investigation of a low-temperature Joule-Thomson refrigerating machine, working by use of a non-azeotropic mixture of refrigerants and with a single-stage hermetic compressor. The temperature, hydraulic and power performance of the machine are determined experimentally in relation to the mixed refrigerant (MR) mass charge. Variations of the MR refrigerating machine operating performance with the working mixture mass charge are found to be considerably different from the analogous performance variations of a refrigerating machine charged with a pure refrigerant. The peculiarities of those relationships are analyzed theoretically. The specific value of a minimum acceptable MR mass charge for the investigated system and its correlation with internal processes in the machine loop are established as well. If the refrigerant mixture mass charges are below the minimum ones, the temperature and power performance of the MR machine differ essentially from the design performance and such operating modes are considered inadmissible. (author)

  20. Fermion Masses and Mixing in General Warped Extra Dimensional Models

    CERN Document Server

    Frank, Mariana; Pourtolami, Nima; Toharia, Manuel

    2015-01-01

    We analyze fermion masses and mixing in a general warped extra dimensional model, where all the Standard Model (SM) fields, including the Higgs, are allowed to propagate in the bulk. In this context, a slightly broken flavor symmetry imposed universally on all fermion fields, without distinction, can generate the full flavor structure of the SM, including quarks, charged leptons and neutrinos. For quarks and charged leptons, the exponential sensitivity of their wave-functions to small flavor breaking effects yield naturally hierarchical masses and mixing as it is usual in warped models with fermions in the bulk. In the neutrino sector, the exponential wave-function factors can be flavor-blind and thus insensitive to the small flavor symmetry breaking effects, directly linking their masses and mixing angles to the flavor symmetric structure of the 5D neutrino Yukawa couplings. The Higgs must be localized in the bulk and the model is naturally more successful in generalized warped scenarios where the metric bac...

  1. Fermion masses and mixing in general warped extra dimensional models

    Science.gov (United States)

    Frank, Mariana; Hamzaoui, Cherif; Pourtolami, Nima; Toharia, Manuel

    2015-06-01

    We analyze fermion masses and mixing in a general warped extra dimensional model, where all the Standard Model (SM) fields, including the Higgs, are allowed to propagate in the bulk. In this context, a slightly broken flavor symmetry imposed universally on all fermion fields, without distinction, can generate the full flavor structure of the SM, including quarks, charged leptons and neutrinos. For quarks and charged leptons, the exponential sensitivity of their wave functions to small flavor breaking effects yield hierarchical masses and mixing as it is usual in warped models with fermions in the bulk. In the neutrino sector, the exponential wave-function factors can be flavor blind and thus insensitive to the small flavor symmetry breaking effects, directly linking their masses and mixing angles to the flavor symmetric structure of the five-dimensional neutrino Yukawa couplings. The Higgs must be localized in the bulk and the model is more successful in generalized warped scenarios where the metric background solution is different than five-dimensional anti-de Sitter (AdS5 ). We study these features in two simple frameworks, flavor complimentarity and flavor democracy, which provide specific predictions and correlations between quarks and leptons, testable as more precise data in the neutrino sector becomes available.

  2. Axial mixing and mass transfer characteristics of pulsed extraction column with discs and doughnuts

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The axial mixing is a key factor for design and scaling up of the pulsed extraction column which has strong influence on the mass transfer performances of the pulsed extraction column with discs and doughnuts. A steady-state concentration profile measurement was used to evaluate the mass transfer and axial mixing coefficients for the nitric acid/water/30%TRPO (in kerosene) system in the pulsed extraction column with the diameter of 38 mm on the condition of the TRPO-kerosene solution as the continuous phase and the flow ratio of 1: 1. Experimental results indicate that Ey evaluated by the experiments is in good agreement with that given by Burratti's correlation; the axial mixing is far smaller for the continuous phase than that for the dispersed phase. However the empirical correlation for Hox is only given based on the present data.

  3. Neutrino Mass and Mixing: from Theory to Experiment

    CERN Document Server

    King, Stephen F; Morisi, Stefano; Shimizu, Yusuke; Tanimoto, Morimitsu

    2014-01-01

    The origin of fermion mass hierarchies and mixings is one of the unresolved and most difficult problem in high-energy physics. One possibility to address the flavour problem is by extending the Standard Model to include a family symmetry. In the recent years it has become very popular to use non-Abelian discrete flavour symmetries because of their power in the prediction of the large leptonic mixing angles relevant for neutrino oscillation experiments. Here we give an introduction to the flavour problem and to discrete groups which have been used to attempt a solution for it. We review the current status of models in the light of the recent measurement of the reactor angle and we consider different model building directions taken. The use of the flavons or multi Higgs scalars in model building is discussed as well as the direct vs. indirect approaches. We also focus on the possibility to distinguish experimentally flavour symmetry models by means of mixing sum rules and mass sum rules. In fact, we illustrate ...

  4. Constraints on the mass and mixing of $Z'$ bosons

    CERN Document Server

    Erler, J; Munir, S; Rojas, E

    2009-01-01

    We tested several models in which the Standard Model (SM) gauge group is extended by an additional U(1) gauge symmetry, against available electroweak precision data to impose limits on the mass of the neutral $Z'$ boson, $M_{Z'}$, predicted in all such models, and on the $Z-Z'$ mixing angle, $\\theta_{ZZ'}$, at 95% C.L. We found lower limits on $M_{Z'}$ of order $1 {\\rm TeV}$ in most cases, while $\\theta_{ZZ'}$ was found to be constrained to very small values.

  5. Renormalisation running of masses and mixings in UED models

    CERN Document Server

    Cornell, A S; Liu, Lu-Xin; Tarhini, Ahmad

    2012-01-01

    We review the Universal Extra-Dimensional Model compactified on a S1/Z2 orbifold, and the renormalisation group evolution of quark and lepton masses, mixing angles and phases both in the UED extension of the Standard Model and of the Minimal Supersymmetric Standard Model. We consider two typical scenarios: all matter fields propagating in the bulk, and matter fields constrained to the brane. The resulting renormalisation group evolution equations in these scenarios are compared with the existing results in the literature, together with their implications.

  6. Water masses of Visakhapatnam shelf

    Digital Repository Service at National Institute of Oceanography (India)

    RamaRaju, V.S.; Sarma, V.V.; Rao, B.P.; Rao, V.S.

    The T-S relationships of shelf waters off Visakhapatnam in the Bay of Bengal are studied for the different seasons with the data collected during February 1979 to January 1981. The T-S relationships indicate distinct characteristics of the water...

  7. The water mass variability on the Romanian Black Sea shelf

    Science.gov (United States)

    Buga, Luminita; Mihailov, Maria-Emanuela; Malciu, Viorel; Stefan, Sabina

    2013-04-01

    The long-term trends in the water mass thermohaline structure and the effect of Danube River freshwater discharge into the western Black Sea during the last four decades (1971 - 2010) are analyzed using the data collected on the Romanian shelf (NIMRD data base). The variations of the temperature and salinity over the studied period are relatively small. The temperature data reveal a slightly warming trend for the upper mixed layer (UML) while for the shelf cold water (SCW) - identified by the 8˚C upper isotherm depth - thermohaline structure remains practically constant. At the same time the salinity exhibits a decreasing trend in the entire water column.

  8. Pseudoscalar glueball mass from $\\eta$-$\\eta'$-$G$ mixing

    CERN Document Server

    Cheng, Hai-Yang; Liu, Keh-Fei

    2008-01-01

    We deduce the mass of the pseudoscalar glueball $G$ from an $\\eta$-$\\eta'$-$G$ mixing formalism based on the anomalous Ward identity for transition matrix elements. With the inputs from the recent KLOE experiment, we find a solution for the pseudoscalar glueball mass around $(1.4\\pm 0.1)$ GeV, which is fairly insensitive to a range of inputs with or without Okubo-Zweig-Iizuka-rule violating effects. This affirms that $\\eta(1405)$, having a large production rate in the radiative $J/\\Psi$ decay and not seen in $\\gamma\\gamma$ reactions, is indeed a leading candidate for the pseudoscalar glueball. Other relevant quantities including the anomaly and pseudoscalar density matrix elements are obtained. The decay widths for $G\\to \\gamma\\gamma$, $\\ell^+\\ell^-$ are also predicted.

  9. Mixed dark matter with low-mass bosons

    CERN Document Server

    Larsen, G B; Larsen, Georg B; Madsen, Jes

    1996-01-01

    We calculate the linear power spectrum for a range of mixed dark matter (MDM) models assuming a massive (few eV) boson, \\phi, instead of a neutrino as the hot component. We consider both the case where the hot dark matter (HDM) particle is a boson and the cold component is some other unknown particle, and the case where there is only one dark matter particle, a boson, with the cold dark matter (CDM) component in a Bose condensate. Models resembling the latter type could arise from neutrino decays - we discuss some variants of this idea. The power spectra for MDM models with massive bosons are almost identical to neutrino MDM models for a given mass fraction of HDM if the bosons are distinct from their antiparticles (\\phi\

  10. Mixed phase effects on high-mass twin stars

    CERN Document Server

    Alvarez-Castillo, D E

    2014-01-01

    Recently it has been found that a certain class of hybrid star equations of state with a large latent heat (strong first order phase transition obtained by a Maxwell construction) between stiff hadronic hadronic and stiff quark matter phases allows for the appearance of a third family of compact stars (including "twins") at high mass of $\\sim 2 M_\\odot$. We investigate how robust this high-mass twin phenomenon is against a smoothing of the transition which would occur, e.g., due to pasta structures in the mixed phase. To this end we propose a simple construction of a pasta-like equation of state with a parameter that quantifies the degree of smoothing of the transition and could eventually be related to the surface tension of the pasta structures. It is interesting to note that the range of energy densities for the transition as well as the pressure at the onset of the transition of this class of hybrid star matter at zero temperature corresponds well to values of the same quantities found in finite temperatu...

  11. Neutrino masses and mixings: Status of known and unknown $3\

    CERN Document Server

    Capozzi, F; Marrone, A; Montanino, D; Palazzo, A

    2016-01-01

    Within the standard 3nu mass-mixing framework, we present an up-to-date global analysis of neutrino oscillation data (as of January 2016), including the latest available results from experiments with atmospheric neutrinos (Super-Kamiokande and IceCube DeepCore), at accelerators (first T2K anti-nu and NOvA nu runs in both appearance and disappearance mode), and at short-baseline reactors (Daya Bay and RENO far/near spectral ratios), as well as a reanalysis of older KamLAND data in the light of the "bump" feature recently observed in reactor spectra. We discuss improved constraints on the five known oscillation parameters (delta m^2, |Delta m^2|, sin^2theta_12, sin^2theta_13, sin^2theta_23), and the status of the three remaining unknown parameters: the mass hierarchy, the theta_23 octant, and the possible CP-violating phase delta. With respect to previous global fits, we find that the reanalysis of KamLAND data induces a slight decrease of both delta m^2 and sin^2theta_12, while the latest accelerator and atmos...

  12. Multiphoton ionization of pyrrole-water mixed clusters

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Multiphoton ionization of the hydrogen-bonded pyrrole-water clusters ( C4H5 N)n H2O)m is studied with a reflectron—time of flight mass spectrometer at 355 nm. With increasing partial concentration of pyrrole in a gas mixture source, a series of poly-pyrrole-water binary-mixed cluster ions can be observed, including unprotonated cluster ions [(C4H5N)x (H2O)y]* , protonated cluster ions [(C4H5N)x (H2O)yH]* and dehydrogenated cluster ions [ ( C4 H4 N) ( C4 H5 N) x ( H2O) y ] + . Ab initio calculations of their structures, bond strengths, charge distributions and re action energies are carried out. Stable structures of these clusters are obtained from the calculations. A probable forma tion mechanism of the cluster ions [(C4H5N)x(H2O)y] + , [(C4H5N)x (H2O)y]H+ and [(C4H4N) (C4H5N)x (H2O)y]-is supposed to be the ionization of clusters followed by dissociation.

  13. CP violation and neutrino masses and mixings from quark mass hierarchies

    Energy Technology Data Exchange (ETDEWEB)

    Buchmueller, W.; Covi, L. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Emmanuel-Costa, D. [CFTP, Departamento de Fisica, Istituto Superior Tecnico, Lisbon (Portugal); Wiesenfeldt, S. [Illinois Univ., Urbana-Champaign, IL (United States). Dept. of Physics

    2007-10-15

    We study the connection between quark and lepton mass matrices in a supersymmetric SO(10) GUT model in six dimensions, compactified on an orbifold. The physical quarks and leptons are mixtures of brane and bulk states. This leads to a characteristic pattern of mass matrices and high-energy CP violating phases. The hierarchy of up and down quark masses determines the CKM matrix and most charged lepton and neutrino masses and mixings. The small hierarchy of neutrino masses is a consequence of the mismatch of the up and down quark mass hierarchies. The effective CP violating phases in the quark sector, neutrino oscillations and leptogenesis are unrelated. In the neutrino sector we can accomodate naturally sin {theta}{sub 23} {proportional_to}1, sin {theta}{sub 13}

  14. Mixing Corrosion of CaCO3 in Natural Waters

    Directory of Open Access Journals (Sweden)

    Qian Hui

    2011-01-01

    Full Text Available The methods of aqueous speciation calculation, pH calculation and the solubility (precipitability calculation of CaCO3 were used to study the mixing corrosion of CaCO3 in natural waters. Mixing processes were done between two unsaturated (with CaCO3 solutions, two oversaturated solutions and between an unsaturated solution and an oversaturated solution, respectively. Results show that the mixing corrosion can be divided into two different levels: mixing corrosion in strict sense and mixing corrosion in broad sense. When mixing corrosion occurs, the HCO3- concentration in one end member solution is usually higher than that in the other solution, and the Ca2+ concentration in the former solution is also usually higher than that in the latter one.

  15. The influence of mixing water and abrasives on the quality of machined surface

    Directory of Open Access Journals (Sweden)

    A. Stoić

    2014-04-01

    Full Text Available This paper shows the impact of mixing water and abrasives in water jet cutting process on the quality of the machined surface. The tests were done with polymer material SIPAS, where the influence of cutting parameters was researched (cutting pressure, cutting feed and abrasive mass flow. The surface roughness was measured on several zones, regarding the depth of materials, because the roughness is increased with the material thickness.

  16. Monitoring Continental Water Mass Variations by GRACE

    Science.gov (United States)

    Mercan, H.; Akyılmaz, O.

    2015-12-01

    The low-low satellite-to-satellite tracking mission GRACE (Gravity Recovery And Climate Experiment), launched in March 2002, aims to determine Earth's static gravity field and its temporal variations. Geophysical mass changes at regional and global scale, which are related with terrestrial water bodies, ocean and atmosphere masses, melting and displacements of ice sheets and tectonic movements can be determined from time-dependent changes of the Earth's gravity field. In this study, it is aimed to determine total water storage (TWS) (soil moisture, groundwater, snow and glaciers, lake and river waters, herbal waters) variations at different temporal and spatial resolution, monitoring the hydrologic effect causing time-dependent changes in the Earth's gravity field by two different methods. The region between 30°-40° northern latitudes and 36°-48° eastern longitudes has been selected as a study area covering the Euphrates - Tigris basin. TWS maps were produced with (i) monthly temporal and 400 km spatial resolution, based on monthly mean global spherical harmonic gravity field models of GRACE satellite mission (L2), and with (ii) monthly and semi-monthly temporal and spatial resolution as fine as 200 km based on GRACE in-situ observations (L1B). Decreasing trend of water mass anomalies from the year 2003 to 2013 is proved by aforesaid approaches. Monthly TWS variations are calculated using two different methods for the same region and time period. Time series of both solutions are generated and compared.

  17. Unsteady Mass transfer Across the Sediment-Water Interface

    Science.gov (United States)

    McCluskey, Alexander; Grant, Stanley; Stewardson, Michael

    2017-04-01

    Fluxes across the sediment-water interface (SWI) are of high ecological significance, as they promote biogeochemical processes that support benthic ecosystems within the hyporheic zone. The SWI marks a boundary between the turbulent water column (typically modelled by Navier Stokes equations) and the interstitial pore fluids in the sediment column, which are typically laminar (and modelled by Darcy's law). Although models of these two flow regimes are generally not coupled, flow in the turbulent boundary layer is affected by the sediment permeability and a slip velocity at the SWI, which decays exponentially into the streambed across a characteristic mixing length. Momentum is transferred across this region (known as the Brinkman layer) through the penetration of coherent structures and turbulent mixing, however, these turbulent structures also promote turbulent mass transfer. Mass transfer within the hyporheic zone can be conceptualised in terms of: (1) the downwelling of solutes from the stream; (2) retention of solutes in the sediment; and (3) the upwelling of solutes back into the stream. Recent work by the authors has shown that a mass transfer coefficient can be defined where a downwelling-upwelling unit cell exists across a concentration gradient. Such unit cells are generated at the SWI by pressure variation from: (1) steady-state influences, such as stream geometry and velocity variation; and (2) unsteady pressure waves produced by coherent turbulent structures. With this definition, mass transfer coefficients can be defined for: steady exchange, by adopting the Elliott and Brooks [1997] advective pumping model; and unsteady exchange, induced by streamwise propagation of upwelling-downwelling unit cells migrating downstream with a characteristic celerity associated with turbulent eddies. We hypothesize that beneath the Brinkman layer (where Laplace equation applies) these mass transfer coefficients can be summed to yield the total mass flux. Although, it

  18. Testing mixed action approaches to meson spectroscopy with twisted mass sea quarks

    CERN Document Server

    Berlin, Joshua; Wagner, Marc

    2013-01-01

    We explore and compare three mixed action setups with Wilson twisted mass sea quarks and different valence quark actions: (1) Wilson twisted mass, (2) Wilson twisted mass + clover and (3) Wilson + clover. Our main goal is to reduce lattice discretization errors in mesonic spectral quantities, in particular to reduce twisted mass parity and isospin breaking.

  19. The mixing of particle clouds plunging into water

    Energy Technology Data Exchange (ETDEWEB)

    Angelini, S.; Theofanous, T.G.; Yuen, W.W. [Univ. of California, Santa Barbara, CA (United States)

    1995-09-01

    This work addresses certain fundamental aspects of the premixing phase of steam explosions, At issue are the multifield interaction aspects under highly transient, multidimensional conditions, and in presence of strong phase changes. They are addressed in an experiment (the MAGICO-2000) involving well-characterized particle clouds mixing with water, and detailed measurements on both external and internal characteristics of the mixing zone. Both cold and hot (up to 1500{degrees}C) particle clouds are considered in conjunction with saturated and subcooled water pools. The PMALPHA code is used as an aid in interpreting the experimental results, and the exercise reveals good predictive capabilities for it.

  20. Three-Flavor Analysis of Neutrino Mixing with and without Mass Hierarchy

    CERN Document Server

    Minakata, H

    1996-01-01

    I summarize the results of barely model-dependent phenomenological analyses of the structure of the neutrino flavor mixing. The analyses are based on the three-flavor mixing framework without sterile neutrinos and utilize the hints from solar and atmospheric neutrino observations as well as that from mixed dark matter cosmology. It will be demonstrated that the features of the analysis is sharply distinguished by the two cases (I) with and (II) without dark matter mass scale, and by whether one (or two) mass is dominant (OMD) or the three states are almost degenerate (ADN). The global features of the neutrino mixing is illuminated for these different mass patterns.

  1. Mixed Meson Mass for Domain-Wall Valence and Staggered Sea Fermions

    Energy Technology Data Exchange (ETDEWEB)

    Konstantinos Orginos; Andre Walker-Loud

    2007-05-01

    Mixed action lattice calculations allow for an additive lattice spacing dependent mass renormalization of mesons composed of one sea and one valence quark, regardless of the type of fermion discretization methods used in the valence and sea sectors. The value of the mass renormalization depends upon the lattice actions used. This mixed meson mass shift is the most important lattice artifact to determine for mixed action calculations: because it modifies the pion mass, it plays a central role in the low energy dynamics of all hadronic correlation functions. We determine the leading order and next to leading order additive mass renormalization of valence-sea mesons for a mixed lattice action with domain-wall valence fermions and staggered sea fermions. We find that on the asqtad improved coarse MILC lattices, the leading order additive mass renormalization for the mixed mesons is Δ(am)^2 LO = 0.0409(11) which corresponds to a^2 Δ_Mix = (319 MeV)^2± (53 MeV)^2 for a = 0.125 fm. We also find significant next to leading order contributions which reduce the mass renormalization by a significant amount, such that for 0 < am_π ≤ 0.22 the mixed meson mass renormalization is well approximated by Δ(am)^2 = 0.0340 (23) or a^2δ_Mix = (290 MeV)^2 ± (76 MeV)^2. The full next-to-leading order analysis is presented in the text.

  2. Mesoscale eddy effects on the wintertime vertical mixing in the formation region of the North Pacific Subtropical Mode Water

    Institute of Scientific and Technical Information of China (English)

    PAN Aijun; LIU Qinyu

    2005-01-01

    Mesoscale eddy effects on the wintertime vertical mixing in the formation region of the North Pacific Subtropical Mode Water (NPSTMW) are studied using hydrographic data from Argo profiling floats deployed in the Kuroshio recirculation region in February and March of 2001. Anticyclonic (warm) eddy enhances the wintertime vertical mixing and results in the deep mixed layer and the deep thermocline. Consequently, a large volumetric water mass with low potential vorticity corresponding to the prototype of NPSTMW tends to be formed. By contrast, cyclonic (cold) eddy is unfavorable for the vertical mixing process and halts the deepening of the mixed layer and thus the formation of mode water. Further analysis shows that cyclonic eddies prevail in the late 1990s in the formation region of NPSTMW, which lead to significant suppression of the wintertime vertical mixing (96-98) and thus are unfavorable for the formation of NPSTMW; while the situation is completely reversed in the early 1990s (93-95).

  3. Experimental study on mixing efficiency in water supply rectangular tanks

    Science.gov (United States)

    Bateman, A.; Medina, V.; Mujal, A.

    2009-04-01

    Phenomenon of mixing in drinking water storage tanks and reservoirs has a direct effect on the quality of water. Creation of poor mixing zones and volume stratification can have negative effects in public health. The design of a storage tank must consider the conditions of the inlet and outlets, and also their orientation (vertical or horizontal) to prevent the formation of these zones. Experiments done in a reduced scaled-model with a rectangular base and three different inlets (two waterfalls and a pipe inlet) had the objective to decide which of these inlets achieved the best mixing efficiency. Four situations were considered while three entrances, two unsteady: filling and drawing, and two steady with different outlets. Moreover the effects of columns that support the roof of the tank were studied by running the three entrances with and without columns in the four situations. Neglecting the viscous scale effects, the time taken to mix the volume stored depends on the distance between the inlet and the opposite wall as though as its orientation. Taking into account the whole tank columns have a negative effect on mixing efficiency although they divide the flux and create local zones of turbulence around them, increasing local mixing. Using a digital treating image technique the results are found in a quantitative way.

  4. Friedberg-Lee Symmetry for Quark Masses and Flavor Mixing

    CERN Document Server

    Ren, Ping

    2008-01-01

    We point out a generic correlation between the Friedberg-Lee symmetry of quark mass operators and the vanishing of quark masses. We make phenomenological explorations on two textures of quark mass matrices with the broken Friedberg-Lee symmetry. We present a new pattern of quark mass matrices in agreement with current experimental data. Both analytical and numerical results of our calculations are discussed in detail.

  5. The hydrography of the mid-latitude northeast Atlantic Ocean. I: The deep water masses

    Science.gov (United States)

    van Aken, Hendrik M.

    2000-05-01

    The circulation of the deep water masses in the mid-latitude northeast Atlantic Ocean was studied by analysis of the distributions of potential temperature, salinity, dissolved oxygen, phosphate, nitrate, and silicate. Pre-formed nutrients were used to allow a quantitative description of the deep water masses, especially the Northeast Atlantic Deep Water, in terms of four local source water types: Iceland-Scotland Overflow Water, Lower Deep Water, Labrador Sea Water, and Mediterranean Sea Water. Over the Porcupine Abyssal Plain between 2500 and 2900 dbar Northeast Atlantic Deep Water appears to be a mixture of mainly Iceland-Scotland Overflow Water and Labrador Sea Water (˜80%), with minor contributions of Lower Deep Water and Mediterranean Sea Water. When the Northeast Atlantic Deep Water re-circulates in the north-eastern Atlantic and flows southwards towards the Madeira Abyssal Plain, contributions of the former two water types of northern origin diminish to about 50% due to diapycnal mixing with the overlying and underlying water masses. The observed meridional and zonal trends of dissolved oxygen and nutrients in the Northeast Atlantic Deep Water appear to be caused both by diapycnal mixing with the underlying Lower Deep Water and by mineralization of organic matter. The eastward decrease of oxygen and increase of nutrients especially require considerable mineralization of organic matter near the European continental margin. At deeper levels (˜4100 dbar), where the nutrient rich Lower Deep Water is found near the bottom, the meridional gradients of oxygen and nutrients are opposite to those found between 2500 and 2900 dbar. Diapycnal mixing cannot explain this change in gradients, which is therefore considered to be a qualitative indication of ageing of the Lower Deep Water when it flows northwards. A considerable part of the Iceland-Scotland Overflow Water and the Lower Deep Water that enter the northeast Atlantic may be removed by deep upwelling in the Bay

  6. Lepton family symmetries for neutrino masses and mixing

    Indian Academy of Sciences (India)

    Ernest Ma

    2006-11-01

    I review some of the recent progress (up to December 2005) in applying non-Abelian discrete symmetries to the family structure of leptons, with particular emphasis on the tribimaximal mixing ansatz of Harrison, Perkins and Scott.

  7. The structure and circulation of intermediate, deep and bottom water masses of the North Atlantic

    Science.gov (United States)

    Khmelnitskaya, Olga

    2014-05-01

    Water mass is one of the basic concepts of oceanography. Changing the characteristics of the main water masses in the North Atlantic can be causes of climate variability. The purpose of the present study is a quantitative assessment of the characteristics of water masses using the Optimum multiparameter (OMP) analysis. OMP analysis of water masses is a continuation of the thermohaline analysis. To study water mass mixing besides temperature and salinity such advanced features as concentration of nutrients, CFCs, isotopes, Redfield ratios and potential vorticity are used. Mathematically the OMP analysis is a system of linear equations for each point of the observations. Using four parameters of the water masses one can find the ratio of five water masses in the volume of water being under investigation. To study the structure of the North Atlantic Ocean we were identified eight major water masses: 1) ABW - Antarctic Bottom Water; 2) DSOW - Denmark Strait Overflow Water; 3) ISOW - Iceland-Scotland Overflow Water; 4) LSW - Labrador Sea Water; 5) MW - Mediterranean Water; 6) AIW - Antarctic Intermediate Water; 7) SPMW - Subpolar Mode Water; 8) STMW - Subtropical Mode Water. Percentage of each water mass was calculated for each section. Upon solving equation systems a data array was performed using the algorithm written in Fortran. The calculations were performed for 12 oceanographic sections made in the North Atlantic (24-64°N) in 1980-2004. We investigated the water masses located deeper than 500 m where there are practically no seasonal changes. On analysis of the water mass percentage in the vertical water sections pathways of intermediate and deep waters can be traced. Comparison of the percentage in the different sections gives an indication of the variability in the intermediate and deep circulation. We calculated the volume of each water mass in the North Atlantic Ocean (24-64°N, 0-77°W) below 500 meters on the basis of data on the percentage of water masses

  8. The model study of water mass and energy exchange between the inland water body and atmosphere

    Institute of Scientific and Technical Information of China (English)

    SUN ShuFen; YAN JinFeng; XIA Nan; LI Qian

    2008-01-01

    Based on a one-dimensional eddy diffusion model, a model to study the water mass and energy exchange between the water body (such as lake and wetland) and the atmosphere is developed, which takes the phase change process due to the seasonal melting and freezing of water and the convection mixing process of en-ergy caused by temperature stratification into consideration. The model uses en-thalpy instead of temperature as predictive variable, which will help to deal with the phase change process and to design an efficient numerical scheme for obtaining the solution more easily. The performance of the model and the rationality of taking convection mixing into the consideration are validated by using observed data of Kinneret Lake in Israel and Lower Two Medicine Lake in Montana State in America. The comparison of model results with observed data indicates that the model pre-sented here is capable of describing the physical process of water mass and en-ergy between the water body (lake and wetland) and atmosphere. Comparison of the result from wetland with shallow and deep lakes under the same forcing condi-tions shows that the evaporation from wetland is much greater than that from lakes,which accords with the real observation fact and physical mechanism.

  9. The model study of water mass and energy exchange between the inland water body and atmosphere

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on a one-dimensional eddy diffusion model,a model to study the water mass and energy exchange between the water body(such as lake and wetland) and the atmosphere is developed,which takes the phase change process due to the seasonal melting and freezing of water and the convection mixing process of energy caused by temperature stratification into consideration. The model uses enthalpy instead of temperature as predictive variable,which will help to deal with the phase change process and to design an efficient numerical scheme for obtaining the solution more easily. The performance of the model and the rationality of taking convection mixing into the consideration are validated by using observed data of Kinneret Lake in Israel and Lower Two Medicine Lake in Montana State in America. The comparison of model results with observed data indicates that the model presented here is capable of describing the physical process of water mass and energy between the water body(lake and wetland) and atmosphere. Comparison of the result from wetland with shallow and deep lakes under the same forcing conditions shows that the evaporation from wetland is much greater than that from lakes,which accords with the real observation fact and physical mechanism.

  10. A novel and economical explanation for SM fermion masses and mixings

    Science.gov (United States)

    Hernández, A. E. Cárcamo

    2016-09-01

    I propose the first multiscalar singlet extension of the standard model (SM), which generates tree level top quark and exotic fermion masses as well as one and three loop level masses for charged fermions lighter than the top quark and for light active neutrinos, respectively, without invoking electrically charged scalar fields. That model, which is based on the S3× Z8 discrete symmetry, successfully explains the observed SM fermion mass and mixing pattern. The charged exotic fermions induce one loop level masses for charged fermions lighter than the top quark. The Z8 charged scalar singlet χ generates the observed charged fermion mass and quark mixing pattern.

  11. Neutrino masses and mixing: a flavour symmetry roadmap

    CERN Document Server

    Morisi, S

    2012-01-01

    Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete symmetries, which provide a simple way to account for the TBM pattern. We discuss phenomenological implications such as neutrinoless double beta decay, lepton flavour violation as well as theoretical aspects such as the possibility to explain quarks and leptons within a common framework, such as grand unified models.

  12. Sneutrino-antisneutrino mixing and neutrino mass in anomaly-mediated supersymmetry breaking scenario.

    Science.gov (United States)

    Choi, Kiwoon; Hwang, Kyuwan; Song, Wan Young

    2002-04-01

    In supersymmetric models with nonzero Majorana neutrino mass, the sneutrino and antisneutrino mix, which may lead to same-sign dilepton signals in future collider experiments. We point out that the anomaly-mediated supersymmetry breaking scenario has a good potential to provide an observable rate of such signals for the neutrino masses suggested by the atmospheric and solar neutrino oscillations. It is noted also that the sneutrino-antisneutrino mixing can provide much stronger information on some combinations of the neutrino masses and mixing angles than the neutrino experiments.

  13. Experimental investigation of mixing of non-isothermal water streams at BWR operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bergagio, Mattia, E-mail: bergagio@kth.se [AlbaNova University Center, Nuclear Reactor Technology Division, Department of Physics, Royal Institute of Technology, 106 91 Stockholm (Sweden); Anglart, Henryk, E-mail: henryk@kth.se [AlbaNova University Center, Nuclear Reactor Technology Division, Department of Physics, Royal Institute of Technology, 106 91 Stockholm (Sweden); Institute of Heat Engineering, Warsaw University of Technology, 21/25 Nowowiejska Street, 00-665 Warsaw (Poland)

    2017-06-15

    Highlights: • Temperatures are measured in the presence of mixing at BWR operating conditions. • The thermocouple support is moved along a pattern to extend the measurement region. • Uncertainty of 1.58 K for temperatures acquired at 1000 Hz. • Momenta of the hot streams and thermal stratification affect the data examined. • Unconventional spectral analysis is required to further study the data collected. - Abstract: In this experimental investigation, wall surface temperatures have been measured during mixing of three water streams in the annular gap between two coaxial stainless-steel tubes. The inner tube, with an outer diameter of 35 mm and a thickness of 5 mm, holds six K-type, ungrounded thermocouples with a diameter of 0.5 mm, which measured surface temperatures with a sampling rate of either 100 Hz or 1000 Hz. The tube was rotated from 0 to 360° and moved in a range of 387 mm in the axial direction to allow measurements of surface temperatures in the whole mixing region. The outer tube has an inner diameter of 80 mm and a thickness of 10 mm to withstand a water pressure of 9 MPa. A water stream at a temperature of either 333 K or 423 K and a Reynolds number between 1657 and 8410 rose vertically in the annular gap and mixed with two water streams at a temperature of 549 K and a Reynolds number between 3.56 × 10{sup 5} and 7.11 × 10{sup 5}. These two water streams entered the annulus radially on the same axial level, 180° apart. Water pressure was kept at 7.2 MPa. Temperature recordings were performed at five axial and eight azimuthal locations, for each set of boundary conditions. Each recording lasted 120 s to provide reliable data on the variance, intermittency and frequency of the surface temperature time series at hand. Thorough calculations indicate that the uncertainty in the measured temperature is of 1.58 K. The mixing region extends up to 0.2 m downward of the hot inlets. In most cases, measurements indicate non-uniform mixing in the

  14. Energy generation from mixing salt water and fresh water: smart flow strategies for reverse electrodialysis

    NARCIS (Netherlands)

    Vermaas, David

    2014-01-01

    Renewable energy can be generated from mixing salt water and fresh water, e.g., seawater and river water. This energy is captured in reverse electrodialysis (RED), using ion exchange membranes that are selective for positive or negative ions. This PhD thesis evaluates the current limitations and fut

  15. Bounds on sterile neutrino mixing for cosmologically interesting mass range

    CERN Document Server

    Nunokawa, H; Rossi, A; Valle, José W F

    1999-01-01

    This talk summarizes our recent work which studied the impact of resonant neutrino) conversions on supernova physics, under the assumption that the mass of the sterile state is in the few eV -cosmologically significant range.

  16. Water in Protoplanetary Disks: Deuteration and Turbulent Mixing

    CERN Document Server

    Furuya, Kenji; Nomura, Hideko; Hersant, Franck; Wakelam, Valentine

    2013-01-01

    We investigate water and deuterated water chemistry in turbulent protoplanetary disks. Chemical rate equations are solved with the diffusion term, mimicking turbulent mixing in vertical direction. Water near the midplane is transported to the disk atmosphere by turbulence and destroyed by photoreactions to produce atomic oxygen, while the atomic oxygen is transported to the midplane and reforms water and/or other molecules. We find that this cycle significantly decreases column densities of water ice at r < 30 AU, where dust temperatures are too high to reform water ice effectively. The radial extent of such region depends on the desorption energy of atomic hydrogen. Our model indicates that water ice could be deficient even outside the sublimation radius. Outside this radius, the cycle decreases the D/H ratio of water ice from 2x10^-2, which is set by the collapsing core model, to 10^-4-10^-2 in 10^6 yr, without significantly decreasing the water ice column density. The resultant D/H ratios depend on the ...

  17. Water diffusion in bicelles and the mixed bicelle model.

    Science.gov (United States)

    Soong, Ronald; Macdonald, Peter M

    2009-01-06

    To test a prediction of the mixed bicelle model, stimulated echo (STE) pulsed field gradient (PFG) (1)H nuclear magnetic resonance (NMR) measurements of water diffusion between and across bicellar lamellae were performed in positively and negatively magnetically aligned bicelles, composed of mixtures of DHPC (1,2-dihexanoyl-sn-glycero-3-phosphocholine) and DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine), as a function of temperature and of the proportion of added short-chain lipid DHPC. (31)P NMR spectra obtained for each situation confirmed that the DHPC undergoes fast exchange between curved and planar regions as per the mixed bicelle model and permitted an estimate of the proportion of the two DHPC populations. Water diffusion across the bicellar lamellae was shown to scale directly with q*, the fraction of edge versus planar phospholipid, rather than simply the ratio q, the global fraction of long-chain to short-chain phospholipid. Geometric modeling of the dependence of water diffusion on q* suggested an upper limit of 400 A for the size of DHPC-rich toroidal perforations within the bicelle lamellae. These findings constitute an independent confirmation of the mixed bicelle model in which DHPC is not confined to edge regions but enjoys, instead, a finite miscibility with DMPC.

  18. Correction to Neutrino Mass Square Difference in the Co-Bimaximal Mixings due to Quantum Gravity

    Science.gov (United States)

    Koranga, Bipin Singh; Narayan, Mohan

    2017-08-01

    We consider non-renormalizable interaction term as a perturbation of the neutrino mass matrix. We assume that the neutrino masses and mixing arise through physics at a scale intermediate between Planck scale and the electroweak breaking scale. We also assume that, just above the electroweak breaking scale, neutrino masses are nearly degenerate and their mixing is Co-bimaximal mixing by assumming mixing angle θ _{13}≠ 0=10°,θ _{23}=π/4, tanθ _{12}2= {1-3sinθ _{13}2}/{2}=34° and Dirac phase δ =± π/2. Quantum gravity (Planck scale effects) lead to an effective S U(2) L × U(1) invariant dimension-5 Lagrangian involving neutrino and Higgs fields. On symmetry breaking, this operator gives rise to correction to the above masses and mixing. The gravitational interaction M X = M p l , we find that for degenerate neutrino mass spectrum, the considered perturbation term change the {Δ }_{21}^' } by 12% and {Δ }_{31}^' } mass square difference is unchanged above GUT scale. The nature of gravitational interaction demands that the element of this perturbation matrix should be independent of flavor indices. In this paper, we study the quantum gravity effects on neutrino mass square difference, namely modified dispersion relation for neutrino mass square differences.

  19. Numerical simulation of transverse mixing of waters at the confluence of two rivers

    Science.gov (United States)

    Lyubimova, Tatyana; Lepikhin, Anatoliy; Parshakova, Yanina

    2017-04-01

    Surface water bodies, both natural (rivers, lakes) and artificial (ponds, reservoirs) are the main source of drinking water. In this regard, special attention should be paid to their pollution, first of all, to extreme pollution, creating a direct danger to their consumption properties. Traditionally, it is believed that the primary mechanism of the pollutants transport in surface water bodies is the Fick diffusion for which the concentration and nature of the pollutants does not affect the transport mechanisms. However, recent studies have shown that these traditional concepts are not always acceptable. In some cases, even relatively low concentrations of pollutants can fundamentally change the hydrodynamics of a flow through a change in density. Density effects playing in these cases an important role can be very important in solving applied problems of water consumption. One an important question is the mechanism of the formation of the streams do not mixing at large distances from the place of confluence of two rivers with significantly different physical and chemical properties of water. In particular, the Vishera river and the Kama river in Perm Region, as evidenced by the numerous space- and aero photographs, virtually do not mix from the place of their confluence to the territory of Solikamsk-Berezniki industrial area. This is fundamentally important for solving the problem of regulation of technological impacts of this source of technogenic pollution, largest in the basin of the Kama river. In the present paper, the phenomenon of a significant weakening of the transverse mixing of water masses in the surface water bodies is investigated with the help of the numerical simulation of the transverse mixing of water masses at the confluence of two rivers. The calculations are carried out with the help of CFD package ANSYS Fluent using k-epsilon model to describe the turbulent pulsations. The dependence of the transverse mixing speed on the flow rates in the

  20. Water masses and property distribution in the EEZ of Mauritius

    Digital Repository Service at National Institute of Oceanography (India)

    DeSousa, S.N.; Singbal, S.Y.S.; George, M.D.

    Water masses and their properties have been studied in the Mauritian during September-October, 1987. Surface water is characterizEd. by two water masses: 1) a warm (temp. 27 degrees C) and relatively saline water (salinity 35.3 x 10 sup(-3)) which...

  1. A physical meaning of mixed gluon-ghost condensate of mass dimension two

    Science.gov (United States)

    Kondo, Kei-Ichi

    2003-10-01

    We demonstrate that a clear physical content and relevance can be attributed to the on-shell BRST-invariant mixed gluon-ghost condensate of mass dimension two which was recently proposed by the author. We argue that a gauge invariant observable is associated with the mixed condensate.

  2. A physical meaning of mixed gluon--ghost condensate of mass dimension two

    CERN Document Server

    Kondo, K I

    2003-01-01

    We demonstrate that a clear physical content and relevance can be attributed to the on-shell BRST-invariant mixed gluon--ghost condensate of mass dimension two which was recently proposed by the author. We argue that a gauge invariant observable is associated with the mixed condensate.

  3. Neutrino masses and deviation from tribimaximal mixing in Δ (27 ) model with inverse seesaw mechanism

    Science.gov (United States)

    Abbas, Mohammed; Khalil, Shaaban; Rashed, Ahmed; Sil, Arunansu

    2016-01-01

    We propose a scheme, based on Δ (27 ) flavor symmetry and supplemented by other discrete symmetries and the inverse seesaw mechanism, where both the light neutrino masses and the deviation from tribimaximal mixing matrix can be linked to the source of lepton number violation. The hierarchies of the charged leptons are explained. We find that the quark masses including their hierarchies and the mixing can also be constructed in a similar way.

  4. Parameterization of ocean wave-induced mixing processes for finite water depth

    Institute of Scientific and Technical Information of China (English)

    YANG Yongzeng; ZHAN Run; TENG Yong

    2009-01-01

    Three dimensional wave-induced mixing plays an important role in shallow water area. A quite direct approach through the Reynolds average upon characteristic length scale is proposed to parameterize the horizontal and vertical shallow water mixing. Comparison of finite depth case with infinite depth results indicates that the difference of the wave-induced mixing strength is evident. In the shallow water condition, the infinite water depth approximation overestimates the mixing strength in the lower layers. The nonzero horizontal wave-induced mixing presents anisotropic property near the shore. The Prandtl's mixing length theory underestimated the wave-induced mixing in the previous studies.

  5. Direct mass limits for chiral fourth-generation quarks in all mixing scenarios.

    Science.gov (United States)

    Flacco, Christian J; Whiteson, Daniel; Tait, Tim M P; Bar-Shalom, Shaouly

    2010-09-10

    Present limits on chiral fourth-generation quark masses mb' and mt' are broadly generalized and strengthened by combining both t' and b' decays and considering a full range of t' and b' flavor-mixing scenarios with the lighter generations (to 1-‖V44‖2≈10(-13)). Various characteristic mass-splitting choices are considered. With mt'>mb' we find that CDF Collaboration limits on the b' mass vary by no more than 10%-20% with any choice of flavor mixing, while for the t' mass, we typically find stronger bounds, in some cases up to mt'>430  GeV. For mb'>mt', we find mb'>380-430  GeV, depending on the flavor mixing and the size of the mt'-mb' mass splitting.

  6. How mixing during hot water draw-offs influence the thermal performance of small solar domestic hot water systems

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    2005-01-01

    CFD calculations on the mixing during hot water draw-offs in vertical hot water tanks with different diameters have been carried out. The calculations, which were carried out with the same cold water inlet design, showed that the extent of mixing is strongly influenced by the tank diameter. The e...... consideration of the required hot water comfort.......CFD calculations on the mixing during hot water draw-offs in vertical hot water tanks with different diameters have been carried out. The calculations, which were carried out with the same cold water inlet design, showed that the extent of mixing is strongly influenced by the tank diameter....... The extent of mixing is increasing for increasing tank diameter. Further, calculations of the yearly thermal performance of small solar domestic hot water systems with hot water tanks with different mixing rates during hot water draw-offs were carried out. Both solar domestic hot water systems with mantle...

  7. Near maximal atmospheric mixing in neutrino mass matrices with two vanishing minors

    Energy Technology Data Exchange (ETDEWEB)

    Dev, S., E-mail: dev5703@yahoo.com [Department of Physics, Himachal Pradesh University, Shimla 171005 (India); Gupta, Shivani, E-mail: shiroberts_1980@yahoo.co.in [Department of Physics, Himachal Pradesh University, Shimla 171005 (India); Gautam, Radha Raman, E-mail: gautamrrg@gmail.com [Department of Physics, Himachal Pradesh University, Shimla 171005 (India); Singh, Lal, E-mail: lalsingh96@yahoo.com [Department of Physics, Himachal Pradesh University, Shimla 171005 (India)

    2011-12-06

    In the flavor basis there are seven cases of two vanishing minors in the neutrino mass matrix which can accommodate the present neutrino oscillation data including the recent T2K data. It is found that two of these cases, namely B{sub 5} and B{sub 6} predict near maximal atmospheric neutrino mixing in the limit of large effective neutrino mass. This feature remains irrespective of the values of solar and reactor mixing angles. A non-zero reactor mixing angle is naturally accommodated in these textures.

  8. Higgs Mass Constraints on a Fourth Family: Upper and Lower Limits on CKM Mixing

    Energy Technology Data Exchange (ETDEWEB)

    Chanowitz, Michael S.

    2010-06-25

    Theoretical and experimental limits on the Higgs boson mass restrict CKM mixing of a possible fourth family beyond the constraints previously obtained from precision electroweak data alone. Existing experimental and theoretical bounds on m{sub H} already significantly restrict the allowed parameter space. Zero CKM mixing is excluded and mixing of order {theta}{sub Cabbibo} is allowed. Upper and lower limits on 3-4 CKM mixing are exhibited as a function of m{sub H}. We use the default inputs of the Electroweak Working Group and also explore the sensitivity of both the three and four family fits to alternative inputs.

  9. Overlap valence quarks on a twisted mass sea. A case study for mixed action lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Cichy, Krzysztof [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Poznan Univ. (Poland). Faculty of Physics; Drach, Vincent; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Garcia-Ramos, Elena [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Humboldt-Universitaet, Berlin (Germany); Herdoiza, Gregorio [UAM/CSIC Univ. Autonoma de Madrid (Spain). Dept. de Fisica Teorica; UAM/CSIC Univ. Autonoma de Madrid (Spain). Inst. de Fisica Teorica; Collaboration: European Twisted Mass Collaboration

    2012-11-15

    We discuss a Lattice QCD mixed action investigation employing Wilson maximally twisted mass sea and overlap valence fermions. Using four values of the lattice spacing, we demonstrate that the overlap Dirac operator assumes a point-like locality in the continuum limit. We also show that by adopting suitable matching conditions for the sea and valence theories a consistent continuum limit for the pion decay constant and light baryon masses can be obtained. Finally, we confront results for sea-valence mixed meson masses and the valence scalar correlator with corresponding expressions of chiral perturbation theory. This allows us to extract low energy constants of mixed action chiral perturbation which characterize the strength of unitarity violations in our mixed action setup.

  10. Mixing and mass transfer in a pilot scale U-loop bioreactor

    DEFF Research Database (Denmark)

    Petersen, Leander Adrian Haaning; Villadsen, John; Jørgensen, Sten Bay;

    2017-01-01

    A system capable of handling a large volumetric gas fraction while providing a high gas to liquid mass transfer is a necessity if the metanotrophic bacterium Methylococcus capsulatus is to be used in single cell protein (SCP) production. In this study mixing time and mass transfer coefficients we...

  11. Remote sensing in the mixing zone. [water pollution in Wisconsin

    Science.gov (United States)

    Villemonte, J. R.; Hoopes, J. A.; Wu, D. S.; Lillesand, T. M.

    1973-01-01

    Characteristics of dispersion and diffusion as the mechanisms by which pollutants are transported in natural river courses were studied with the view of providing additional data for the establishment of water quality guidelines and effluent outfall design protocols. Work has been divided into four basic categories which are directed at the basic goal of developing relationships which will permit the estimation of the nature and extent of the mixing zone as a function of those variables which characterize the outfall structure, the effluent, and the river, as well as climatological conditions. The four basic categories of effort are: (1) the development of mathematical models; (2) laboratory studies of physical models; (3) field surveys involving ground and aerial sensing; and (4) correlation between aerial photographic imagery and mixing zone characteristics.

  12. Radiative seesaw-type mechanism of fermion masses and non-trivial quark mixing

    Energy Technology Data Exchange (ETDEWEB)

    Arbelaez, Carolina; Hernandez, A.E.C.; Kovalenko, Sergey; Schmidt, Ivan [Universidad Tecnica Federico Santa Maria, Centro Cientifico-Tecnologico de Valparaiso-CCTVal, Valparaiso (Chile)

    2017-06-15

    We propose a predictive inert two-Higgs doublet model, where the standard model (SM) symmetry is extended by S{sub 3} x Z{sub 2} x Z{sub 12} and the field content is enlarged by extra scalar fields, charged exotic fermions and two heavy right-handed Majorana neutrinos. The charged exotic fermions generate a non-trivial quark mixing and provide one-loop-level masses for the first- and second-generation charged fermions. The masses of the light active neutrinos are generated from a one-loop-level radiative seesaw mechanism. Our model successfully explains the observed SM fermion mass and mixing pattern. (orig.)

  13. Gaugino mass mixing in SUSY GUTs with two Abelian gauge groups

    Energy Technology Data Exchange (ETDEWEB)

    Braam, F. [Freiburg Univ. (Germany). Physikalisches Inst.; Reuter, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2011-08-15

    Supersymmetric Grand Unified Theories often involve an additional Abelian group factor apart from the standard model hypercharge. Although in many cases there is a procedure to avoid loop-induced mixing of the gauge kinetic terms by choosing a suitable basis for the two U(1) groups in group space, a residual mixing in the soft SUSY breaking gaugino mass terms remains. In this letter we generalize the renormalization group equations for the gaugino mass terms to account for this effect. In a further calculation we also present the necessary adjustments in the renormalization group equations of the trilinear soft breaking couplings and the soft breaking scalar mass squares. (orig.)

  14. Radiative seesaw-type mechanism of fermion masses and non-trivial quark mixing

    Science.gov (United States)

    Arbeláez, Carolina; Hernández, A. E. Cárcamo; Kovalenko, Sergey; Schmidt, Ivan

    2017-06-01

    We propose a predictive inert two-Higgs doublet model, where the standard model (SM) symmetry is extended by S3⊗ Z2⊗ Z_{12} and the field content is enlarged by extra scalar fields, charged exotic fermions and two heavy right-handed Majorana neutrinos. The charged exotic fermions generate a non-trivial quark mixing and provide one-loop-level masses for the first- and second-generation charged fermions. The masses of the light active neutrinos are generated from a one-loop-level radiative seesaw mechanism. Our model successfully explains the observed SM fermion mass and mixing pattern.

  15. Vertical variation of oxygen isotope in Bay of Bengal and its relationships with water masses

    Science.gov (United States)

    Sengupta, S.; Parekh, Anant; Chakraborty, S.; Ravi Kumar, K.; Bose, T.

    2013-12-01

    We present here, for the first time, comprehensive depth specific (near surface to 1800 m) oxygen isotope (δ18O) data set of 175 water samples collected from 22 different locations in the Bay of Bengal (BoB) during July-August 2009 and December-January 2012-2013. The study is aimed to constrain the water mass parameters using oxygen isotope and salinity. Four water masses are identified on the basis of temperature-salinity relationship: (a) Bay of Bengal Water (BoBW; 0-50 m), (b) Mixed Zone (MZ; 60-120 m), (c) Indonesian Throughflow (ITF; 200-500 m), and (d) Indian Ocean Deep Water (IDW; 600-1800 m). Our study shows: (1) δ18O-salinity correlation (slope = 0.15 ± 0.01; intercept = -4.58 ± 0.24; r2 = 0.89; n = 54) for the BoBW is found to be consistent with surface BoB water reported earlier, (2) relatively lower correlation (r2 = 0.24; n = 47) in underlying mixed zone suggesting mixing of various water masses, (3) significant linear correlation between δ18O and salinity in IDW (r2 = 0.70) indicating depleted less saline water from southern hemisphere spread up to 18°N, and (4) vertical profiles at various sampling locations showing a continuous enrichment of δ18O (0.6-0.8‰) within top 60-100 m irrespective of their proximity to coastline. In conjunction with a sharp decrease in Δ14C data below the same depth zone (60-100 m) as reported earlier, we suggest the δ18O value reaches to its acme at a zone of mixing between younger BoBW and relatively older ITF. This preliminary study indicates oxygen isotope and salinity together can be used to identify different water masses in the BoB.

  16. Mass transport in mixed conducting perovskite related oxides

    CERN Document Server

    Shaw, C K M

    2001-01-01

    mechanical and chemical stability of LSCN under practical operating temperatures have been measured and related to long term stability in typical SOFC assemblies. The phase stability and the effect of preparation conditions under different atmospheres on La sub 2 Ni sub 1 sub - sub x Co sub x O sub 4 sub + subdelta compounds were examined using high temperature X-ray diffraction. Fast oxygen uptake at low temperatures was observed in these studies indicating rapid oxygen diffusion, which was confirmed by isotope exchange investigations. The oxygen diffusion and surface exchange data obtained from IEDP-SIMS measurements of La sub 2 Ni sub 0 sub . sub 8 Co sub 0 sub . sub 2 O sub 4 sub + subdelta have enabled suppositions to be made regarding the reduction process and aided further interpretation of the defect model for these oxides. Mixed ionic electronic conducting oxides of the perovskite structure have attracted great interest in the field of solid oxide electrochemical devices. Their ability to allow poten...

  17. Predictive model for radiatively induced neutrino masses and mixings with dark matter.

    Science.gov (United States)

    Gustafsson, Michael; No, Jose M; Rivera, Maximiliano A

    2013-05-24

    A minimal extension of the standard model to naturally generate small neutrino masses and provide a dark matter candidate is proposed. The dark matter particle is part of a new scalar doublet field that plays a crucial role in radiatively generating neutrino masses. The symmetry that stabilizes the dark matter also suppresses neutrino masses to appear first at three-loop level. Without the need of right-handed neutrinos or other very heavy new fields, this offers an attractive explanation of the hierarchy between the electroweak and neutrino mass scales. The model has distinct verifiable predictions for the neutrino masses, flavor mixing angles, colliders, and dark matter signals.

  18. How mixing during hot water draw-offs influence the thermal performance of small solar domestic hot water systems

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    2005-01-01

    CFD calculations on the mixing during hot water draw-offs in vertical hot water tanks with different diameters have been carried out. The calculations, which were carried out with the same cold water inlet design, showed that the extent of mixing is strongly influenced by the tank diameter....... The extent of mixing is increasing for increasing tank diameter. Further, calculations of the yearly thermal performance of small solar domestic hot water systems with hot water tanks with different mixing rates during hot water draw-offs were carried out. Both solar domestic hot water systems with mantle......, and that a decreased auxiliary volume in the tanks and an increased height/diameter ratio of the tanks will increase the thermal performance of the systems. The investigations showed further, that mixing during hot water draw-offs decreases the thermal performance of solar domestic hot water systems. The mixing...

  19. Water mass of the northward throughflow in the Bering Strait in the summer of 2003

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jinping; SHI Jiuxin; GAO Guoping; JIAO Yutian; ZHANG Hongxin

    2006-01-01

    The temperature and salinity data obtained by the Chinese national arctic research expedition (CHINARE2003) are used to study the water structure in the Bering Strait and ambient regions. Four water masses appeared in the research region: the intermediate Bering Sea water mass (IBWM), the Alaska coastal water (ACW), the Anadyr water (AW) and the Bering shelf water (BSW). The AW originates from the IBWM, but the upper layer water has been greatly altered. In the cruise on 28/29 July 2003, there were only the BSW and ACW in a section across the Bering Strait (BS section), but in the September 12/13 cruise, the AW, BSW and ACW flowed parallelly into the Bering Strait. The upper waters of these water masses were all altered due to ice melting, runoff, solar radiation, and wind mixing. The waters in the central and northern parts of Bering Strait stratified by two uniform layers,were expressed as the typical feature of the water masses originating from the pacific. A two-layer structure also dominated the vertical stratification in most part of the Chukchi Sea. An obvious subseasonal variation was observed in the BS section, which caused varying transportation of fresh water,heat, and substance, and produced a long-term and extensive impact on the Arctic Ocean.

  20. Water masses as a unifying framework for understanding the Southern Ocean Carbon Cycle

    Directory of Open Access Journals (Sweden)

    D. Iudicone

    2011-05-01

    Full Text Available The scientific motivation for this study is to understand the processes in the ocean interior controlling carbon transfer across 30° S. To address this, we have developed a unified framework for understanding the interplay between physical drivers such as buoyancy fluxes and ocean mixing, and carbon-specific processes such as biology, gas exchange and carbon mixing. Given the importance of density in determining the ocean interior structure and circulation, the framework is one that is organized by density and water masses, and it makes combined use of Eulerian and Lagrangian diagnostics. This is achieved through application to a global ice-ocean circulation model and an ocean biogeochemistry model, with both components being part of the widely-used IPSL coupled ocean/atmosphere/carbon cycle model.

    Our main new result is the dominance of the overturning circulation (identified by water masses in setting the vertical distribution of carbon transport from the Southern Ocean towards the global ocean. A net contrast emerges between the role of Subantarctic Mode Water (SAMW, associated with large northward transport and ingassing, and Antarctic Intermediate Water (AAIW, associated with a much smaller export and outgassing. The differences in their export rate reflects differences in their water mass formation processes. For SAMW, two-thirds of the surface waters are provided as a result of the densification of thermocline water (TW, and upon densification this water carries with it a substantial diapycnal flux of dissolved inorganic carbon (DIC. For AAIW, principal formatin processes include buoyancy forcing and mixing, with these serving to lighten CDW. An additional important formation pathway of AAIW is through the effect of interior processing (mixing, including cabelling that serve to densify SAMW.

    A quantitative evaluation of the contribution of mixing, biology and gas exchange to the DIC evolution per water mass reveals that

  1. A novel and economical explanation for SM fermion masses and mixings

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, A.E.C. [Universidad Tecnica Federico Santa Maria and Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile)

    2016-09-15

    I propose the first multiscalar singlet extension of the standard model (SM), which generates tree level top quark and exotic fermion masses as well as one and three loop level masses for charged fermions lighter than the top quark and for light active neutrinos, respectively, without invoking electrically charged scalar fields. That model, which is based on the S{sub 3} x Z{sub 8} discrete symmetry, successfully explains the observed SM fermion mass and mixing pattern. The charged exotic fermions induce one loop level masses for charged fermions lighter than the top quark. The Z{sub 8} charged scalar singlet χ generates the observed charged fermion mass and quark mixing pattern. (orig.)

  2. A Model of Fermion Masses and Flavor Mixings with Family Symmetry $SU(3)\\otimes U(1)$

    CERN Document Server

    Yang, Wei-Min; Zhong, Jin-Jin

    2011-01-01

    The family symmetry $SU(3)\\otimes U(1)$ is proposed to solve flavor problems about fermion masses and flavor mixings. It's breaking is implemented by some flavon fields at the high-energy scale. In addition a discrete group $Z_{2}$ is introduced to generate tiny neutrino masses, which is broken by a real singlet scalar field at the middle-energy scale. The low-energy effective theory is elegantly obtained after all of super-heavy fermions are integrated out and decoupling. All the fermion mass matrices are regularly characterized by four fundamental matrices and thirteen parameters. The model can perfectly fit and account for all the current experimental data about the fermion masses and flavor mixings, in particular, it finely predicts the first generation quark masses and the values of $\\theta^{\\,l}_{13}$ and $J_{CP}^{\\,l}$ in neutrino physics. All of the results are promising to be tested in the future experiments.

  3. Neutrino mixing and masses in SO(10) GUTs with hidden sector and flavor symmetries

    CERN Document Server

    Chu, Xiaoyong

    2016-01-01

    We consider the neutrino masses and mixing in the framework of SO(10) GUTs with hidden sector consisting of fermionic and bosonic SO(10) singlets and flavor symmetries. The framework allows to disentangle the CKM physics responsible for the CKM mixing and different mass hierarchies of quarks and leptons and the neutrino new physics which produces smallness of neutrino masses and large lepton mixing. The framework leads naturally to the relation $U_{PMNS} \\sim V_{CKM}^{\\dagger} U_0$, where structure of $U_0$ is determined by the flavor symmetry. The key feature of the framework is that apart from the Dirac mass matrices $m_D$, the portal mass matrix $M_D$ and the mass matrix of singlets $M_S$ are also involved in generation of the lepton mixing. This opens up new possibilities to realize the flavor symmetries and explain the data. Using $A_4 \\times Z_4$ as the flavor group, we systematically explore the flavor structures which can be obtained in this framework depending on field content and symmetry assignment...

  4. Neutrino mixing and masses in SO(10) GUTs with hidden sector and flavor symmetries

    Science.gov (United States)

    Chu, Xiaoyong; Smirnov, Alexei Yu.

    2016-05-01

    We consider the neutrino masses and mixing in the framework of SO(10) GUTs with hidden sector consisting of fermionic and bosonic SO(10) singlets and flavor symmetries. The framework allows to disentangle the CKM physics responsible for the CKM mixing and different mass hierarchies of quarks and leptons and the neutrino new physics which produces smallness of neutrino masses and large lepton mixing. The framework leads naturally to the relation U PMNS ˜ V CKM † U 0, where structure of U 0 is determined by the flavor symmetry. The key feature of the framework is that apart from the Dirac mass matrices m D , the portal mass matrix M D and the mass matrix of singlets M S are also involved in generation of the lepton mixing. This opens up new possibilities to realize the flavor symmetries and explain the data. Using A 4 × Z 4 as the flavor group, we systematically explore the flavor structures which can be obtained in this framework depending on field content and symmetry assignments. We formulate additional conditions which lead to U 0 ˜ U TBM or U BM. They include (i) equality (in general, proportionality) of the singlet flavons couplings, (ii) equality of their VEVs; (iii) correlation between VEVs of singlets and triplet, (iv) certain VEV alignment of flavon triplet(s). These features can follow from additional symmetries or be remnants of further unification. Phenomenologically viable schemes with minimal flavon content and minimal number of couplings are constructed.

  5. Solvation of Lithium Irons in Mixed Organic Electrolyte Solutions by Electrospray Ionization Mass Spectroscopy

    OpenAIRE

    MATSUDA, Yoshiharu; FUKUSHIMA, Tsuyoshi; Hashimoto, Hiroyuki; ARAKAWA, Ryuichi

    2002-01-01

    Solvation of lithium ions in mixed organic electrolyte solutions for secondary lithium batteries was investigated by electrospray ionization mass spectroscopy. The electrolyte solutions were mixed binary solutions of diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylene carbonate (EC),γ-butyrolactone (GBL), and propylene carbonate (PC) containing LiClO4. Lithium ions solvated mainly to two solvent molecules. The order of the inclination of the solvent molecules solvating to lithium ions...

  6. Characteristic time scales of mixing, mass transfer and biomass growth in a Taylor vortex algal photobioreactor.

    Science.gov (United States)

    Gao, Xi; Kong, Bo; Vigil, R Dennis

    2015-12-01

    Recently it has been demonstrated that algal biomass yield can be enhanced using fluid flow patterns known as Taylor vortices. It has been suggested that these growth rate improvements can be attributed to improved light delivery as a result of rapid transport of microorganisms between light and dark regions of the reactor. However, Taylor vortices also strongly impact fluid mixing and interphase (gas-liquid) mass transport, and these in turn may also explain improvements in biomass productivity. To identify the growth-limiting factor in a Taylor vortex algal photobioreactor, experiments were performed to determine characteristic time scales for mixing and mass transfer. By comparing these results with the characteristic time scale for biomass growth, it is shown that algal growth rate in Taylor vortex reactors is not limited by fluid mixing or interphase mass transfer, and therefore the observed biomass productivity improvements are likely attributable to improved light utilization efficiency.

  7. Effect of soil pollution on water for mixing of concrete

    Science.gov (United States)

    Muñoz, M. Cecilia Soto; Tapia Alvarez, Carolina; Decinti Weiss, Alejandra; Zamorano Vargas, Macarena; Corail Sanchez, Camila; Hurtado Nuñez, Camilo; Guzman Hermosilla, Matías; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Borras, Jaume Bech; Roca, Nuria

    2016-04-01

    ISO 12439, in addition to chemical and physical requirements, establishes maximum levels for harmful substances that may be present in the mixing water of concrete, when they come from natural sources from contaminated soils. These harmful substances considered in the ISO are sugars, phosphates (P2O5), nitrate (NO3-), lead (P2+) and zinc (Zn2+). As an alternative to the maximum values, ISO verifies the effect of these substances in water from contaminated soils. This measurement is made on the effect on the mechanical strength of the concrete (compression at 7 and 28 days) and the setting times (start and end setting). This paper presents the results obtained on samples of concrete made with smaller, similar and more content to the maximum levels set by ISO 12439 are presented. The results establish that in the case of nitrate, a substance present in many contaminated soils margins resistance variation or setting times allowed by ISO 12439 are not met. Finally, it is concluded that in case of presence of these pollutants should be performed strength tests and setting times before authorizing the use of water. Keywords: Harmful substances, contaminated soils, water pollution.

  8. Dimethylamine biodegradation by mixed culture enriched from drinking water biofilter.

    Science.gov (United States)

    Liao, Xiaobin; Chen, Chao; Zhang, Jingxu; Dai, Yu; Zhang, Xiaojian; Xie, Shuguang

    2015-01-01

    Dimethylamine (DMA) is one of the important precursors of drinking water disinfection by-product N-nitrosodimethylamine (NDMA). Reduction of DMA to minimize the formation of carcinogenic NDMA in drinking water is of practical importance. Biodegradation plays a major role in elimination of DMA pollution in the environment, yet information on DMA removal by drinking water biofilter is still lacking. In this study, microcosms with different treatments were constructed to investigate the potential of DMA removal by a mixed culture enriched from a drinking water biofilter and the effects of carbon and nitrogen sources. DMA could be quickly mineralized by the enrichment culture. Amendment of a carbon source, instead of a nitrogen source, had a profound impact on DMA removal. A shift in bacterial community structure was observed with DMA biodegradation, affected by carbon and nitrogen sources. Proteobacteria was the predominant phylum group in DMA-degrading microcosms. Microorganisms from a variety of bacterial genera might be responsible for the rapid DMA mineralization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Water mass dynamics shape Ross Sea protist communities in mesopelagic and bathypelagic layers

    Science.gov (United States)

    Zoccarato, Luca; Pallavicini, Alberto; Cerino, Federica; Fonda Umani, Serena; Celussi, Mauro

    2016-12-01

    Deep-sea environments host the largest pool of microbes and represent the last largely unexplored and poorly known ecosystems on Earth. The Ross Sea is characterized by unique oceanographic dynamics and harbors several water masses deeply involved in cooling and ventilation of deep oceans. In this study the V9 region of the 18S rDNA was targeted and sequenced with the Ion Torrent high-throughput sequencing technology to unveil differences in protist communities (>2 μm) correlated with biogeochemical properties of the water masses. The analyzed samples were significantly different in terms of environmental parameters and community composition outlining significant structuring effects of temperature and salinity. Overall, Alveolata (especially Dinophyta), Stramenopiles and Excavata groups dominated mesopelagic and bathypelagic layers, and protist communities were shaped according to the biogeochemistry of the water masses (advection effect and mixing events). Newly-formed High Salinity Shelf Water (HSSW) was characterized by high relative abundance of phototrophic organisms that bloom at the surface during the austral summer. Oxygen-depleted Circumpolar Deep Water (CDW) showed higher abundance of Excavata, common bacterivores in deep water masses. At the shelf-break, Antarctic Bottom Water (AABW), formed by the entrainment of shelf waters in CDW, maintained the eukaryotic genetic signature typical of both parental water masses.

  10. The numerical investigation of seasonal variation of the cold water mass in the Beibu Gulf and its mechanisms

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhenhua; QIAO Fangli; XIA Changshui; WANG Gang

    2015-01-01

    A wave-tide-circulation coupled model based on the Princeton Ocean Model is established to explore the seasonal variation of the cold water mass in the Beibu Gulf and its mechanisms. The results show that the cold water mass starts forming in March, reaches the maximum strength during June and July, and fades away since October. Strong mixing in winter transports the cold water from sea surface to bottom. The cold water mass remains in the bottom layer as the thermocline strengthens during spring, except for the shallow water where the themocline is broken by strong tidal mixing, which gradually separate the cold water mass from its surrounding warm water. Further analysis on the ocean current and stream function confirms that the cold water mass in the Beibu Gulf is locally developed, with an anticlockwise circulation caused by a strong temperature gradient. Sensitivity experiments reveal that the cold water mass is controlled by the sea surface heat flux, while the terrain and tidal mixing also play important roles.

  11. Energetic Efficiency of Mixing and Mass Transfer in Single Phase and Two-Phase Systems

    Directory of Open Access Journals (Sweden)

    Bałdyga Jerzy

    2017-03-01

    Full Text Available In this work a concept of energetic efficiency of mixing is presented and discussed; a classical definition of mixing efficiency is modified to include effects of the Schmidt number and the Reynolds number. Generalization to turbulent flows is presented as well. It is shown how the energetic efficiency of mixing as well as efficiencies of drop breakage and mass transfer in twophase liquid-liquid systems can be identified using mathematical models and test chemical reactions. New expressions for analyzing efficiency problem are applied to identify the energetic efficiency of mixing in a stirred tank, a rotor stator mixer and a microreactor. Published experimental data and new results obtained using new systems of test reactions are applied. It has been shown that the efficiency of mixing is small in popular types of reactors and mixers and thus there is some space for improvement.

  12. Fermion masses and mixing in SU(5)×D4 × U(1) model

    Science.gov (United States)

    Ahl Laamara, R.; Loualidi, M. A.; Miskaoui, M.; Saidi, E. H.

    2017-03-01

    We propose a supersymmetric SU (5) ×Gf GUT model with flavor symmetry Gf =D4 × U (1) providing a good description of fermion masses and mixing. The model has twenty eight free parameters, eighteen are fixed to produce approximative experimental values of the physical parameters in the quark and charged lepton sectors. In the neutrino sector, the TBM matrix is generated at leading order through type I seesaw mechanism, and the deviation from TBM studied to reconcile with the phenomenological values of the mixing angles. Other features in the charged sector such as Georgi-Jarlskog relations and CKM mixing matrix are also studied.

  13. Bi-large Neutrino Mixing See-Saw Mass Matrix with Texture Zeros and Leptogenesis

    Institute of Scientific and Technical Information of China (English)

    CHAO Wei; HE Xiao-Gang; LI Xue-Qian

    2006-01-01

    We study constraints on neutrino properties for a class of bi-large mixing See-Saw mass matrices with texture zeros and with the related Dirac neutrino mass matrix to be proportional to a diagonal matrix of the form diag(e, 1, 1). Texture zeros may occur in the light (class a)) or in the heavy (class b)) neutrino mass matrices. Each of these two classes has 5 different forms which can produce non-trivial three generation mixing with at least one texture zero. We find that two types of texture zero mass matrices in both class a and class b can be consistent with present data on neutrino masses and mixing. None of the neutrinos can have zero masses and the lightest of the light neutrinos has a mass larger than about 0.046 eV for class a and 0.0027 eV for class b. In these models although the CKM CP violating phase vanishes, the non-zero Majorana phases can exist and can play an important role in producing the observed baryon asymmetry in our universe through leptogenesis mechanism. The requirement of producing the observed baryon asymmetry can further distinguish different models and also restrict the See-Saw scale to be in the range of 1012 ~ 1015GeV. We also discuss RG effects on V13.

  14. Flavor Mixing, CP-Violation and the Masses of the Light Quarks

    CERN Document Server

    Fritzsch, Harald

    1998-01-01

    The observed hierarchy of the quark masses is interpreted as a signal for an underlying ``subnuclear democracy'' as the relevant symmetry of the quark mass terms. A simple breaking of the symmetry leads to a mixing between the second and the third family, in agreement with observation. Introducing the mixing between the first and the second family, one finds an interesting pattern of maximal CP--violation as well as a complete determination of the elements of the CKM matrix and of the unitarity triangle.

  15. The double mass hierarchy pattern: simultaneously understanding quark and lepton mixing

    CERN Document Server

    Hollik, Wolfgang Gregor

    2015-01-01

    The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on the fermionic mixing patterns. The quark and lepton mixing matrices are built in a general framework with their matrix elements expressed in terms of the four fermion mass ratios m_u/m_c, m_c/m_t, m_d/m_s, and m_s/m_b and m_e/m_mu, m_mu/m_tau, m_{nu 1}/m_{nu 2}, and m_{nu 2}/m_{nu 3}, for the quark and lepton sector, respectively. In this framework, we show that the resulting mixing matrices are consistent with data for both quarks and leptons, despite the large leptonic mixing angles. The minimal assumption we take is the one of hierarchical masses and minimal flavour symmetry breaking that strongly follows from phenomenology. No special structure of the mass matrices has to be assumed that cannot be motivated by this minimal assumption. This analysis allows us to predict ...

  16. Mixing and mass transfer in a pilot scale U-loop bioreactor

    DEFF Research Database (Denmark)

    Petersen, Leander Adrian Haaning; Villadsen, John; Jørgensen, Sten Bay

    2017-01-01

    determined in a 0.15 m3 forced flow U-loop fermenter of a novel construction. The effect on the impeller drawn power when a gas was introduced into the system was also studied.Mixing time decreased and mass transfer increased with increasing volumetric liquid flow rate and specific power input. This happened......A system capable of handling a large volumetric gas fraction while providing a high gas to liquid mass transfer is a necessity if the metanotrophic bacterium Methylococcus capsulatus is to be used in single cell protein (SCP) production. In this study mixing time and mass transfer coefficients were...... also for a large volume fraction of the gas, which was shown to have only minor effect on the power drawn from the pump impeller.Very large mass transfer coefficients, considerably higher than those obtainable in an STR and previous tubular loop reactors, could be achieved in the U-loop fermenter...

  17. Radiative generation of quark masses and mixing angles in the two Higgs doublet model

    Energy Technology Data Exchange (ETDEWEB)

    Ibarra, Alejandro [Physik-Department T30d, Technische Universität München, James-Franck-Straße, 85748 Garching (Germany); Solaguren-Beascoa, Ana [Physik-Department T30d, Technische Universität München, James-Franck-Straße, 85748 Garching (Germany); Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany)

    2014-09-07

    We present a framework to generate the quark mass hierarchies and mixing angles by extending the Standard Model with one extra Higgs doublet. The charm and strange quark masses are generated by small quantum effects, thus explaining the hierarchy between the second and third generation quark masses. All the mixing angles are also generated by small quantum effects: the Cabibbo angle is generated at zeroth order in perturbation theory, while the remaining off-diagonal entries of the Cabibbo–Kobayashi–Maskawa matrix are generated at first order, hence explaining the observed hierarchy |V{sub ub}|,|V{sub cb}|≪|V{sub us}|. The values of the radiatively generated parameters depend only logarithmically on the heavy Higgs mass, therefore this framework can be reconciled with the stringent limits on flavor violation by postulating a sufficiently large new physics scale.

  18. Near Maximal Atmospheric Neutrino Mixing in Neutrino Mass Models with Two Texture Zeros

    CERN Document Server

    Dev, S; Singh, Lal; Gupta, Manmohan

    2014-01-01

    The implications of a large value of the effective Majorana neutrino mass for a class of two texture zero neutrino mass matrices have been studied in the flavor basis. It is found that these textures predict near maximal atmospheric neutrino mixing angle in the limit of large effective Majorana neutrino mass. It is noted that this prediction is independent of the values of solar and reactor neutrino mixing angles. We present the symmetry realization of these textures using the discrete cyclic group $Z_3$. It is found that the texture zeros realised in this work remain stable under renormalization group running of the neutrino mass matrix from the seesaw scale to the electroweak scale, at one loop level.

  19. Homologous Type of Malignant Mixed Mullerian Tumor of the Uterus Presenting as a Cervical Mass

    Directory of Open Access Journals (Sweden)

    Umur Kuyumcuoğlu

    2009-10-01

    Full Text Available Malignant mixed Mullerian tumors are composed of a mixture of sarcoma and carcinoma. The carcinomatous element is usually glandular, whereas the sarcomatous element may resemble normal endometrial stroma (homologous or so-called carcinosarcoma. Here, we present a homologous type of malignant mixed Mullerian tumor of the uterus that presented as a cervical mass. We describe a 55-year-old patient who had a cervical mass arising from the uterus. We performed total abdominal hysterectomy and bilateral salpingo-oophorectomy and surgical staging (including (peritoneal washings, suspicious areas or peritoneal surfaces sampled, infracolic omental sampling, pelvic and paraaortic lymph node sampling, and appendectomy. Carcinosarcomas of the uterine cervix are extremely rare, and when a post-menopausal woman with a cervical mass is admitted to the gynecology clinic, the physician should keep in mind that the mass might be a carcinosarcoma. [J Chin Med Assoc 2009;72(10:533–535

  20. Radiative generation of quark masses and mixing angles in the two Higgs doublet model

    Directory of Open Access Journals (Sweden)

    Alejandro Ibarra

    2014-09-01

    Full Text Available We present a framework to generate the quark mass hierarchies and mixing angles by extending the Standard Model with one extra Higgs doublet. The charm and strange quark masses are generated by small quantum effects, thus explaining the hierarchy between the second and third generation quark masses. All the mixing angles are also generated by small quantum effects: the Cabibbo angle is generated at zeroth order in perturbation theory, while the remaining off-diagonal entries of the Cabibbo–Kobayashi–Maskawa matrix are generated at first order, hence explaining the observed hierarchy |Vub|,|Vcb|≪|Vus|. The values of the radiatively generated parameters depend only logarithmically on the heavy Higgs mass, therefore this framework can be reconciled with the stringent limits on flavor violation by postulating a sufficiently large new physics scale.

  1. Radiative Generation of Quark Masses and Mixing Angles in the Two Higgs Doublet Model

    CERN Document Server

    Ibarra, Alejandro

    2014-01-01

    We present a framework to generate the quark mass hierarchies and mixing angles by extending the Standard Model with one extra Higgs doublet. The charm and strange quark masses are generated by small quantum effects, thus explaining the hierarchy between the second and third generation quark masses. All the mixing angles are also generated by small quantum effects: the Cabibbo angle is generated at zero-th order in perturbation theory, while the remaining off-diagonal entries of the Cabibbo-Kobayashi-Maskawa matrix are generated at first order, hence explaining the observed hierarchy $|V_{ub}|,|V_{cb}|\\ll |V_{us}|$. The values of the radiatively generated parameters depend only logarithmically on the heavy Higgs mass, therefore this framework can be reconciled with the stringent limits on flavor violation by postulating a sufficiently large new physics scale.

  2. TRACG-CFD analysis of ESBWR reactor water cleanup shutdown cooling system mixing coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, J. [UNAM, Facultad de Ingenieria, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Marquino, W.; Mistreanu, A.; Yang, J., E-mail: euqrop@hotmail.com [General Electric Hitachi Nuclear Energy, Wilmington, 28401 North Carolina (United States)

    2015-09-15

    The ESBWR is a 1520 nominal [M We] Generation III+ natural circulation boiling water reactor designed to high levels of safety utilizing features that have been successfully used before in operating BWRs, as well as standard features common to A BWR. In September of 2014, the US NRC has certified the ESBWR design for use in the USA. The RWCU/Sdc is an auxiliary system for the ESBWR nuclear island. Basic functions it performs include purifying the reactor coolant during normal operation and shutdown and providing shutdown cooling and cooldown to cold shutdown conditions. The performance of the RWCU system during shutdown cooling is directly related to the temperature of the water removed through the outlets, which is coupled with the vessel and F W temperatures through a thermal mixing coefficient. The complex three-dimensional (3-D) geometry of the BWR downcomer and lower plenum has a great impact on the flow mixing. Only a fine mesh technique like CFD can predict the 3-D temperature distribution in the RPV during shutdown and provide the RWCU/Sdc system inlet temperature. Plant shutdown is an unsteady event by nature and was modeled as a succession of CFD steady-state simulations. It is required to establish the mixing coefficient (which is a function of the heat balance and the core flow) during the operation of the RWCU system in the multiple shutdown cooling modes, and therefore a range of core flows needs to be estimated using quasi steady states obtained with TRACG. The lower end of that range is obtained from a system with minimal power decay heat and core flow; while the higher end corresponds to the power at the beginning of RWCU/Sdc operation when the cooldown is transferred to the RWCU/Sdc after the initial depressurization via the turbine bypass valves. Because the ESBWR RWCU/Sdc return and suction designs provide good mixing, the uniform mixing energy balance was found to be an adequate alternative for deriving the mixing coefficient. The CFD mass flow

  3. Water Balance in a Mid-Latitude, Mixed Grass Prairie

    Science.gov (United States)

    Billesbach, D.; Arkebauer, T.

    2003-12-01

    Covering more than 50,000 square kilometers, the Nebraska Sand Hills are the largest stabilized dune field in the world. A unique feature of this region is the close proximity of the land surface to the vast High Plains Aquifier. The land-surface is classified as a mixed grass prairie, and except for a few very small instances, has never been put under the plow. The region is currently home to most of the rangeland cattle industry in Nebraska, and prior to European settlement, was the primary home-range for large herds of North American bison. The co-location of an extensive sub-surface water resource and an inherently semi-arid climate produces an interesting ecosystem, which affords many unique opportunities to study plant-water relationships. We are currently operating a pair of Energy Balance/Bowen Ratio (EBBR) systems to measure evapotranspiration and other ecosystem parameters within key land surface types. We now have 2 growing seasons or more than 20 months of data. We will discuss this data and compare the two seasons in terms of water inputs and outputs.

  4. Implications of measured properties of the mixing matrix on mass matrices

    CERN Document Server

    Chaturvedi, S; Sánchez-Colón, G; Chaturvedi, Subhash; Gupta, Virendra; Sanchez-Colon, Gabriel

    2006-01-01

    It is shown how the two experimentally measurable properties of the mixing matrix $V$, the asymmetry Delta(V)=|V_{12}|^2- |V_{21}|^2 of V with respect to the main diagonal and the Jarlskog invariant J(V)=Im(V_{11}V_{12}^*V_{21}^*V_{22}), can be exploited to obtain constraints on possible structures of mass matrices in the quark sector. Specific mass matrices are examined in detail as an illustration.

  5. Effect of Mixed Corrosion Inhibitors in Cooling Water System

    Directory of Open Access Journals (Sweden)

    Dina Raheem

    2011-01-01

    Full Text Available The effect of mixed corrosion inhibitors in cooling system was evaluated by using carbon steel specimens and weight loss analysis. The carbon steel specimens immersed in mixture of sodium phosphate (Na2 HPO4 used as corrosion inhibitor and sodium glocunate (C6 H11 NaO7 as a scale dispersant at different concentrations (20,40, 60, 80 ppm and at different temperature (25,50,75 and 100ºC for (1-5 days. The corrosion inhibitors efficiency was calculated by using uninhibited and inhibited water to give 98.1%. The result of these investigations indicate that the corrosion rate decreases with the increase the corrosion inhibitors concentration at 80 ppm and at 100ºC for 5 days, (i.e, corrosion rate= 0.014gmd.

  6. Numerical consistency check between two approaches to radiative corrections for neutrino masses and mixings

    Indian Academy of Sciences (India)

    Mrinal Kumar Das; Mahadev Patgiri; N Nimai Singh

    2005-12-01

    We briefly outline the two popular approaches on radiative corrections to neutrino masses and mixing angles, and then carry out a detailed numerical analysis for a consistency check between them in MSSM. We find that the two approaches are nearly consistent with a discrepancy factor of 4.2% with running vacuum expectation value (VEV) (13% for scale-independent VEV) in mass eigenvalues at low-energy scale but the predictions on mixing angles are almost consistent. We check the stability of the three types of neutrino models, i.e., hierarchical, inverted hierarchical and degenerate models, under radiative corrections, using both approaches, and find consistent conclusions. The neutrino mass models which are found to be stable under radiative corrections in MSSM are the normal hierarchical model and the inverted hierarchical model with opposite CP parity. We also carry out numerical analysis on some important conjectures related to radiative corrections in the MSSM, viz., radiative magnification of solar and atmospheric mixings in the case of nearly degenerate model having same CP parity (MPR conjecture) and radiative generation of solar mass scale in exactly two-fold degenerate model with opposite CP parity and non-zero 3 (JM conjecture). We observe certain exceptions to these conjectures. We find a new result that both solar mass scale and 3 can be generated through radiative corrections at low energy scale. Finally the effect of scale-dependent vacuum expectation value in neutrino mass renormalisation is discussed.

  7. Strontium isotopic identification of water-rock interaction and ground water mixing.

    Science.gov (United States)

    Frost, Carol D; Toner, Rachel N

    2004-01-01

    87Sr/86Sr ratios of ground waters in the Bighorn and Laramie basins' carbonate and carbonate-cemented aquifer systems, Wyoming, United States, reflect the distinctive strontium isotope signatures of the minerals in their respective aquifers. Well water samples from the Madison Aquifer (Bighorn Basin) have strontium isotopic ratios that match their carbonate host rocks. Casper Aquifer ground waters (Laramie Basin) have strontium isotopic ratios that differ from the bulk host rock; however, stepwise leaching of Casper Sandstone indicates that most of the strontium in Casper Aquifer ground waters is acquired from preferential dissolution of carbonate cement. Strontium isotope data from both Bighorn and Laramie basins, along with dye tracing experiments in the Bighorn Basin and tritium data from the Laramie Basin, suggest that waters in carbonate or carbonate-cemented aquifers acquire their strontium isotope composition very quickly--on the order of decades. Strontium isotopes were also used successfully to verify previously identified mixed Redbeds-Casper ground waters in the Laramie Basin. The strontium isotopic compositions of ground waters near Precambrian outcrops also suggest previously unrecognized mixing between Casper and Precambrian aquifers. These results demonstrate the utility of strontium isotopic ratio data in identifying ground water sources and aquifer interactions.

  8. Lateral Mixing DRI Analysis: Submesoscale Water-Mass Spectra

    Science.gov (United States)

    2013-09-30

    1984). This requires tapering at large separations to avoid ringing and multiplying by Δr which reduces the signal near Δr = 0 where it is most...Chieh Lien in Luzon Strait that resolves horizontal wavenumbers as high as 100 cpkm shows an order-of-magnitude jump in spectral level near 1 cpkm

  9. Measuring ice- and liquid-water properties in mixed-phase cloud layers at the Leipzig Cloudnet station

    Science.gov (United States)

    Bühl, Johannes; Seifert, Patric; Myagkov, Alexander; Ansmann, Albert

    2016-08-01

    An analysis of the Cloudnet data set collected at Leipzig, Germany, with special focus on mixed-phase layered clouds is presented. We derive liquid- and ice-water content together with vertical motions of ice particles falling through cloud base. The ice mass flux is calculated by combining measurements of ice-water content and particle Doppler velocity. The efficiency of heterogeneous ice formation and its impact on cloud lifetime is estimated for different cloud-top temperatures by relating the ice mass flux and the liquid-water content at cloud top. Cloud radar measurements of polarization and Doppler velocity indicate that ice crystals formed in mixed-phase cloud layers with a geometrical thickness of less than 350 m are mostly pristine when they fall out of the cloud.

  10. Distribution of nanoflagellates in five water masses of the East China Sea in autumn and winter

    Science.gov (United States)

    Lin, Shiquan; Huang, Lingfeng; Zhu, Zhisheng; Xiong, Yuan; Lu, Jiachang

    2016-02-01

    The variations of abundance, biomass and trophic structure of nanoflagellates (NF) among five typical water masses in the East China Sea were investigated in autumn (November 19-December 23, 2006) and winter (February 22-March 11, 2007). It was found that water mass had a significant impact on the distribution of NF. Either in autumn or in winter, the highest abundance and biomass of NF were recorded in the East China Sea Shelf Mixing Water (ECSSMW), and the lowest in the Kuroshio Subsurface Water (KSSW). While in the East China Sea Coastal Water (ECSCW), the abundance and biomass of both heterotrophic nanoflagellates (HNF) and pigmented phototrophic nanoflagellates (PNF) were only slightly higher than that in Taiwan Strait Water (TSW) and Kuroshio Surface Water (KSW). In respect to the seasonal variation, the abundance and biomass of NF in TSW declined in winter, while in other 4 water masses, they showed an increasing trend from autumn to winter, mainly due to the decrease (in TSW) or increase (in ECSCW, ECSSMW, KSW and KSSW) of HNF. The distribution pattern of abundance- or biomass-based PNF/HNF ratio was found to be correlated to the nutrient level of the water mass. Results of Pearson correlation analysis and principle component analysis indicated that PNF was mainly constrained by nutrient supply, and HNF was controlled by food availability in the East China Sea.

  11. Asteroseismic test of rotational mixing in low-mass white dwarfs

    CERN Document Server

    Istrate, A G; Gianninas, A; Grassitelli, L; Marchant, P; Tauris, T M; Langer, N

    2016-01-01

    We exploit the recent discovery of pulsations in mixed-atmosphere (He/H), extremely low-mass white dwarf precursors (ELM proto-WDs) to test the proposition that rotational mixing is a fundamental process in the formation and evolution of low-mass helium core white dwarfs. Rotational mixing has been shown to be a mechanism able to compete efficiently against gravitational settling, thus accounting naturally for the presence of He, as well as traces of metals such as Mg and Ca, typically found in the atmospheres of ELM proto-WDs. Here we investigate whether rotational mixing can maintain a sufficient amount of He in the deeper driving region of the star, such that it can fuel, through HeII-HeIII ionization, the observed pulsations in this type of stars. Using state-of-the-art evolutionary models computed with MESA, we show that rotational mixing can indeed explain qualitatively the very existence and general properties of the known pulsating, mixed-atmosphere ELM proto-WDs. Moreover, such objects are very likel...

  12. Revisiting fermion mass and mixing fits in the minimal SUSY $SO(10)$ GUT

    CERN Document Server

    Fukuyama, Takeshi; Mimura, Yukihiro

    2015-01-01

    The supersymmetric $SO(10)$ grand unified models with renormalizable Yukawa couplings involving only ${\\bf 10}$ and $\\overline{\\bf 126}$ Higgs fields have been shown to realize the fermion masses and mixings economically. In previous works, the sum rule of the fermion mass matrices are given by inputting the quark matrices, and the neutrino mixings are predicted in the framework. Now the three neutrino mixings have been measured, and in this paper, we give the sum rule by inputing the lepton mass matrices, which makes clear to show the feature of the solution, especially if the vacuum expectation values of ${\\bf 126}+ \\overline{\\bf126}$ ($v_R$) are large and the right-handed neutrinos are heavy. We perform the $\\chi^2$ analyses to fit the fermion masses and mixings using the sum rule. In the previous works, the best fit appears at $v_R \\sim 10^{13}$ GeV, and the fit at the large $v_R$ scale ($\\sim 10^{16}$ GeV) has been less investigated. We discuss the possible low energy threshold correction of the sum rule...

  13. Higgs portal dark matter and neutrino mass and mixing with a doubly charged scalar

    CERN Document Server

    Hierro, I M; Rigolin, S

    2016-01-01

    We consider an extension of the Standard Model involving two new scalar particles around the TeV scale: a singlet neutral scalar $\\phi$, to be eventually identified as the Dark Matter candidate, plus a doubly charged $SU(2)_L$ singlet scalar, $S^{++}$, that can be the source for the non-vanishing neutrino masses and mixings. Assuming an unbroken $Z_2$ symmetry in the scalar sector, under which only the additional neutral scalar $\\phi$ is odd, we write the most general (renormalizable) scalar potential. The model may be regarded as a possible extension of the conventional Higgs portal Dark Matter scenario which also accounts for neutrino mass and mixing. This framework cannot completely explain the observed positron excess. However a softening of the discrepancy observed in conventional Higgs portal framework can be obtained, especially when the scale of new physics responsible for generating neutrino masses and lepton number violating processes is around 2 TeV.

  14. The water mass structure and transports in the Atlantic Subpolar Gyre

    Science.gov (United States)

    García-Ibáñez, Maribel I.; Pardo, Paula C.; Carracedo, Lidia I.; Mercier, Herlé; Lherminier, Pascale; Ríos, Aida F.; Pérez, Fiz F.

    2014-05-01

    The water mass structure, mixing and spreading in the North Atlantic Subpolar Gyre (SPG) were analyzed by means of an extended Optimum MultiParameter (eOMP) approach over the six repeats of the WOCE A25 hydrographic line located at the southern boundary of this gyre. The data includes the Fourex (4x) line taken in 1997 and the five repeat sections of the OVIDE line taken every other year from 2002 to 2010. We proposed 10 water masses, defined by their thermohaline properties (potential temperature and salinity), oxygen and nutrients (nitrate, phosphate and silicate), to resolve the water mass structure of the SPG. The eOMP enables to decompose the transports by water mass quantitatively. Our model provides water mass distributions that are able to reproduce the input data of potential temperature, salinity and silicate with r2>0.997 and of oxygen, nitrate and phosphate with r2>0.96. By combining the velocity field and the water mass structure across each section we provide the relative contribution of each water mass to the Meridional Overturning Circulation (MOC) and we evaluate the water mass transformation in the North Atlantic. The MOC upper limb during OVIDE (2002-2010) is constituted by the northward transports of the central waters (9.4 Sv; 1 Sv = 106 m3 s-1), the Subarctic Intermediate Water (SAIW, 2.8 Sv) and the Subpolar Mode Water (SPMW) of the Iceland Basin (2.1 Sv). The MOC lower limb is constituted by the southward transports of the Iceland-Scotland Overflow Water (ISOW, 2.9 Sv), the Denmark Strait Overflow Water (DSOW, 2.5 Sv), the Polar Intermediate Water (PIW, 0.8 Sv), the Labrador Sea Water (LSW, 3.6 Sv) and the SPMW of the Irminger Sea (4.7 Sv). These results contrast with those obtained for the 1997, cruise developed after a period of high NAO index. The greater MOC strength in 1997 resulted in greater northward transports of central waters (17.5 Sv), while the SAIW transports remained approximately unchanged. The increase of the northward

  15. Living benthic foraminiferal species as indicators of cold-warm water masses interaction and upwelling areas

    Science.gov (United States)

    Eichler, Patrícia P. B.; Pimenta, Felipe M.; Eichler, Beatriz B.; Vital, Helenice

    2016-03-01

    The western South Atlantic continental margin, between 27° and 37°S, is dominated by four main water masses: cold-fresh Subantarctic Shelf Water (SASW), warm-salty Subtropical Shelf Water (STSW), cold upwelled South Atlantic Central Water (SACW), and fresh Plata Plume Water (PPW). Despite the large seasonal variability of PPW extension along the shelf, an intense and relatively stable temperature-salinity gradient separates the SASW and the STSW forming the Subtropical Shelf Front (STSF) around 32°S. The two dominant shelf water masses (SASW and STSW) arise from the process of mixing of oceanic waters. The SASW originates from the dilution of Subantarctic Water due to excess precipitation and continental runoff, and the STSW consists of modified warm tropical waters and South Atlantic Central Water (SACW) diluted below PPW. A previous article demonstrates distribution of Bulimina marginata, a shelf environment and deep-sea species of benthic foraminifera, is influenced by the front location and it can be used as a proxy of the STSF in sediment core analysis. Here we show three other infaunal living species inhabiting at the Continental margin: Buccella peruviana, Globocassidulina subglobosa and Uvigerina peregrina and their distribution limits show the interaction of Subantartic Shelf Water, Subtropical Shelf Water, and upwelling of SACW, in the bottom sediment of coastal studied areas.

  16. Effect of rotational mixing and metallicity on the hot star wind mass-loss rates

    CERN Document Server

    Krticka, Jiri

    2014-01-01

    Hot star wind mass-loss rates depend on the abundance of individual elements. This dependence is usually accounted for assuming scaled solar chemical composition. However, this approach may not be justified in evolved rotating stars. The rotational mixing brings CNO-processed material to the stellar surface, increasing the abundance of nitrogen at the expense of carbon and oxygen, which potentially influences the mass-loss rates. We study the influence of the modified chemical composition resulting from the rotational mixing on the wind parameters, particularly the wind mass-loss rates. We use our NLTE wind code to predict the wind structure and compare the calculated wind mass-loss rate for the case of scaled solar chemical composition and the composition affected by the CNO cycle. We show that for a higher mass-fraction of heavier elements $Z/Z_\\odot\\gtrsim0.1$ the change of chemical composition from the scaled solar to the CNO-processed scaled solar composition does not significantly affect the wind mass-l...

  17. Pollen, water, and wind: Chaotic mixing in a puddle of water

    DEFF Research Database (Denmark)

    Jensen, Kaare Hartvig

    2016-01-01

    This paper talks about how pine pollen grains dispersedin an approximately 1 m wide and 1 cm deep water puddle. The pollen has mixed due to wind blowing across the liquid surface, revealing a strikingly complex flow pattern. The flows revealed by nature’s tracer particles may influence circulatio......, and typically measures ∼50 μm in diameter. Pollen is transferred from a pollen cone to the ovule by wind or insects, and produces male sperm cells...

  18. The S{sub 3} flavour symmetry: Neutrino masses and mixings

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Canales, F. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico); Facultad de Ciencias de la Electronica, Benemerita Universidad Autonoma de Puebla (Mexico); Mondragon, A.; Mondragon, M. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico)

    2013-04-02

    In this work, we discuss the neutrino masses and mixings as the realization of an S{sub 3} flavour permutational symmetry in two models, namely the Standard Model and an extension of the Standard Model with three Higgs doublets. In the S{sub 3} Standard Model, mass matrices of the same generic form are obtained for the neutrino and charged leptons when the S{sub 3} flavour symmetry is broken sequentially according to the chain S{sub 3L} x S{sub 3R} contains S{sub 3}{sup diag} contains S{sub 2}. In the minimal S{sub 3}-symmetric extension of the Standard Model, the S{sub 3} symmetry is left unbroken, and the concept of flavour is extended to the Higgs sector by introducing in the theory three Higgs fields which are SU(2) doublets. In both models, the mass matrices of the neutrinos and charged leptons are reparametrized in terms of their eigenvalues, and exact, explicit analytical expressions for the neutrino mixing angles as functions of the masses of neutrinos and charged leptons are obtained. In the case of the S{sub 3} Standard Model, from a {chi}{sup 2} fit of the theoretical expressions of the lepton mixing matrix to the values extracted from experiment, the numerical values of the neutrino mixing angles are obtained in excellent agreement with experimental data. In the S{sub 3} extension of the Standard Model, if two of the right handed neutrinos masses are degenerate, the reactor and atmospheric mixing angles are determined by the masses of the charged leptons, yielding {theta}{sub 23} in excellent agreement with experimental data, and {theta}{sub 13} different from zero but very small. If the masses of the three right handed neutrinos are assumed to be different, then it is possible to get {theta}{sub 13}also in very good agreement with experimental data. We also show the branching ratios of some selected flavour changing neutral currents (FCNC) process as well as the contribution of the exchange of a neutral flavour changing scalar to the anomaly of the

  19. Mixing at double-Tee junctions with unequal pipe sizes in water distribution systems

    Science.gov (United States)

    Pipe flow mixing with various solute concentrations and flow rates at pipe junctions is investigated. The degree of mixing affects the spread of contaminants in a water distribution system. Many studies have been conducted on the mixing at the cross junctions. Yet a few have focu...

  20. Convective Heat and Mass Transfer in Water at Super—Critical Pressures under Heating or Cooling Conditions in Vertical Tubes

    Institute of Scientific and Technical Information of China (English)

    Pei-XueJiang; Ze-PeiRen; 等

    1995-01-01

    Forced and mixed convection heat and mass transfer are studied numerically for water containing metallic corrosion products in a heated or cooled vertical tube with variable thermophysical properties at super-citical pressures.the fouling mechanisms and fouling models are presented.The influence of variable properties at super-critical pressures on forced or mixed convection has been analyzed.The differences between heat and mass transfer under heating and cooling conditions are discussed.It is found that variable properties,especially buoyancy,greatly influence the fluid flow and heat mass fransfer.

  1. Background NO/x/ mixing ratios in air masses over the North Atlantic Ocean

    Science.gov (United States)

    Helas, G.; Warneck, P.

    1981-08-01

    Measurements of nitrogen oxide concentrations in clean air masses over the North Atlantic Ocean are reported. The measurements were performed on the west coast of Ireland using the NO-O3 chemiluminescence technique with NO2 reduced to NO by chemical converters. The average NO2 mixing ratio for a three-week period is found to be 101 + or 87 pptv, with significantly lower values in pure marine air masses. A diurnal variation is also observed in the marine air, with nighttime values of 37 + or - 6 pptv and average values of 87 + or - 47 pptv. Under such conditions, the NO mixing ratio was immeasurably small, while the excess NO(x), i.e. other nitrogen oxides, is also found to be higher during the day compared to nighttime values of about 70 pptv.

  2. Broken S_3 Flavor Symmetry of Leptons and Quarks: Mass Spectra and Flavor Mixing Patterns

    CERN Document Server

    Xing, Zhi-zhong; Zhou, Shun

    2010-01-01

    We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of charged leptons (M_l), neutrinos (M_nu), up-type quarks (M_u) and down-type quarks (M_d) have a universal form consisting of two terms: one is proportional to the identity matrix I and the other is proportional to the democracy matrix D. We argue that the textures of M_l, M_u and M_d are dominated by the D term, while that of M_nu is dominated by the I term. This hypothesis implies a near mass degeneracy of three neutrinos and can naturally explain why the mass matrices of charged fermions are strongly hierarchical, why the quark mixing matrix is close to I and why the lepton mixing matrix contains two large angles. We discuss a rather simple perturbation ansatz to break the S_3 symmetry and obtain more realistic mass spectra of leptons and quarks as well as their flavor m...

  3. Granulation of After Reclamation Dusts from the Mixed Sands Technology: Water Glass – Resolit

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2013-04-01

    Full Text Available A technology of sands with water glass hardened by liquid esters is a cheap and ecologic method of producing moulding sands. Due to these advantages, this technology is still very important in several foundry plants for production of heavy iron and steel castings. Reclamation of the mixed moulding and core sands generates significant amounts of dusts, which require further treatments for their reuse. The results of investigations of a pressureless granulation of dusts generated in the dry mechanical reclamation process of the mixture consisting in app. 90 % of moulding sands from the Floster S technology and in 10 % of core sands with phenolic resin resol type, are presented in the hereby paper. Investigations were aimed at obtaining granulates of the determined dimensional and strength parameters. Granules were formed from the mixture of dusts consisting of 75 mass% of dusts after the reclamation of sands mixture and of 25 mass% of dusts from bentonite sands processing plant. Wetted dusts from bentonite sands were used as a binding agent allowing the granulation of after reclamation dusts originated from the mixed sands technology.

  4. Flocculation of metals during mixing of Siyahrud River water with Caspian Sea water.

    Science.gov (United States)

    Biati, Aida; Karbassi, Abdulreza R

    2012-11-01

    Flocculation of dissolved Cu, Mn, Ni, Zn, and Pb during mixing of Siyahrud River water with water sample of Caspian Sea at nine different salinity regimes was investigated. The maximum flocculation of elements occurs in the salinities 1.67‰ to 3.67‰ (except for Zn). The flocculation trend of Zn (80.9) >Mn (58.3) > Cu (30.5) > Ni (25.9) > Pb (19.5) indicates that flocculation of metals have nonlinear behavior towards salinity changes during estuarine mixing. Electrical conductivity shows a linear behavior in different proportions of salinity which is in contrast with the behavior of other studied parameters. Cluster analysis indicates that pH and NO(3) are governing factors in the flocculation of Cu, Mn, and Pb. The results of this research show that 80.9%, 19.5%, 25.9%, 30.5%, and 58.3% of dissolved Zn, Pb, Ni, Cu, and Mn flocculate during estuarine mixing. Total amount of studied dissolved element flowing in to the Caspian Sea would decrease from 5.62 to 2.76 t/year.

  5. Heavy snow: IR spectroscopy of isotope mixed crystalline water ice.

    Science.gov (United States)

    Wong, Andy; Shi, Liang; Auchettl, Rebecca; McNaughton, Don; Appadoo, Dominique R T; Robertson, Evan G

    2016-02-14

    Mid-infrared spectra have been measured for crystalline water ice aerosols of widely varied H/D isotopic composition. Particles with diameters ranging from 10-200 nm were generated via rapid collisional cooling with a cold buffer gas over a range of temperatures from 7-200 K. In near isotopically pure ices, the νL band position is slightly red-shifted with increasing temperature whilst in the ν2 region apparently anomalous shifts in peak maxima are explained by the contribution of a broad 2νL band of H2O and a 3νL band of D2O together with ν2 intensity that is particularly weak in low temperature crystalline ice. The hydrogen bonded OH (or OD) oscillator bands of near pure H2O (or D2O) ices are blue-shifted with temperature, with a gradient very similar to that of the corresponding band in isotope diluted samples, HOD in D2O (or H2O). It implies that this observed temperature trend is predominantly due to the intrinsic change in local hydride stretch potential energy, rather than to changes in intermolecular coupling. However, it is also observed that the narrow hydride stretch bands of an isotope diluted sample rapidly develop sub-band structure as the oscillator concentration increases, evidence of strong intermolecular coupling and a high degree of delocalisation. Anomalous blue-shifts in the OD stretch profile as D2O concentration grows is attributable to Fermi resonance with 2ν2 of D2O, in much closer proximity than the corresponding H2O levels. Theoretical results from a mixed quantum/classical approach are used to validate these findings in the hydride stretching region. Theory qualitatively reproduces the experimental trends as a function of temperature and isotopic variance.

  6. Higgs-boson masses and mixing matrices in the NMSSM: analysis of on-shell calculations

    Energy Technology Data Exchange (ETDEWEB)

    Drechsel, P.; Weiglein, G. [DESY, Hamburg (Germany); Groeber, R. [Durham University, Department of Physics, Institute for Particle Physics Phenomenology, Durham (United Kingdom); INFN, Sezione di Roma Tre, Rome (Italy); Heinemeyer, S. [Campus of International Excellence UAM+CSIC, Madrid (Spain); Universidad Autonoma de Madrid, Instituto de Fisica Teorica, (UAM/CSIC), Madrid (Spain); Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Muehlleitner, M. [Karlsruhe Institute of Technology, Institute for Theoretical Physics, Karlsruhe (Germany); Rzehak, H. [University of Southern Denmark, CP3-Origins, Odense M (Denmark)

    2017-06-15

    We analyze the Higgs-boson masses and mixing matrices in the NMSSM based on an on-shell (OS) renormalization of the gauge-boson and Higgs-boson masses and the parameters of the top/scalar top sector. We compare the implementation of the OS calculations in the codes NMSSMCALC and NMSSM-FeynHiggs up to O(α{sub t}α{sub s}). We identify the sources of discrepancies at the one- and at the two-loop level. Finally we compare the OS and DR evaluation as implemented in NMSSMCALC. The results are important ingredients for an estimate of the theoretical precision of Higgs-boson mass calculations in the NMSSM. (orig.)

  7. Abnormal Structure of Fermion Mixings in a Seesaw Quark Mass Matrix Model

    CERN Document Server

    Koide, Y

    1997-01-01

    It is pointed out that in a seesaw quark mass matrix model which yields a singular enhancement of the top-quark mass, the right-handed fermion-mixing matrix U_R^u for the up-quark sector has a peculiar structure in contrast to the left-handed one U_L^u. As an example of the explicit structures of U_L^u and U_R^u, a case in which the heavy fermion mass matrix M_F is given by a form [(unit matrix)+(rank-one matrix)] is investigated. As a consequence, one finds observable signatures at projected high energy accelerators like the production of a fourth heavy quark family.

  8. Fermion Masses and Mixings in a $\\mu$-$\\tau$ symmetric SO(10)

    CERN Document Server

    Joshipura, Anjan S; Patel, Ketan M

    2009-01-01

    $\\mu$-$\\tau$ symmetry imposed on the neutrino mass matrix in the flavour basis is known to be quite predictive. We integrate this very specific neutrino symmetry into a more general framework based on the supersymmetric SO(10) grand unified theory. As in several other models, the fermion mass spectrum is determined by Hermitian mass matrices resulting from the renormalizable Yukawa couplings of the 16-plet of fermions with the Higgs fields transforming as $10, \\bar{126},120$ representations of the SO(10) group. The $\\mu$-$\\tau$ symmetry is spontaneously broken through the 120-plet. Consequences of this scheme are considered for fermion masses using both type-I and type-II seesaw mechanism. This scenario is shown to lead to a generalized CP invariance of the mass matrices and vanishing CP violating phases if the Yukawa couplings are invariant under the $\\mu$-$\\tau$ symmetry. Small explicit breaking of the $\\mu$-$\\tau$ symmetry is then shown to provide a very good understanding of all the fermion masses and mix...

  9. Majorana ghosts: From topological superconductor to the origin of neutrino masses, three generations and their mass mixing

    CERN Document Server

    Gu, Zheng-Cheng

    2013-01-01

    A cutting-edge step towards understanding the nature of neutrino has been taken by the experimental discovery of neutrino mass mixing during the past decade, which indicates neutrino has a small but non-vanishing mass. A natural way to explain the origin of this small mass is the so-called seesaw mechanism, which requires the neutrino to be a Majorana fermion. Recently, Majorana's spirit returns in modern condensed matter physics -- in the context of Majorana zero modes in certain classes of topological superconductors(TSCs). In this paper, we assume a relativistic Majorana fermion is made up of four Majorana zero modes. We begin with an exactly solvable 1D DIII class TSC and show that the pair of Majorana zero modes on each end will realize a T^4=-1 representation of the time reversal symmetry and carry 1/4 spin. We find that a pair of Majorana zero modes can realize a P^4=-1 parity symmetry and even a \\bar C^4=-1 nontrivial charge conjugation symmetry. We then point out that the nontrivial charge conjugatio...

  10. Intracellular water exchange for measuring the dry mass, water mass and changes in chemical composition of living cells.

    Directory of Open Access Journals (Sweden)

    Francisco Feijó Delgado

    Full Text Available We present a method for direct non-optical quantification of dry mass, dry density and water mass of single living cells in suspension. Dry mass and dry density are obtained simultaneously by measuring a cell's buoyant mass sequentially in an H2O-based fluid and a D2O-based fluid. Rapid exchange of intracellular H2O for D2O renders the cell's water content neutrally buoyant in both measurements, and thus the paired measurements yield the mass and density of the cell's dry material alone. Utilizing this same property of rapid water exchange, we also demonstrate the quantification of intracellular water mass. In a population of E. coli, we paired these measurements to estimate the percent dry weight by mass and volume. We then focused on cellular dry density - the average density of all cellular biomolecules, weighted by their relative abundances. Given that densities vary across biomolecule types (RNA, DNA, protein, we investigated whether we could detect changes in biomolecular composition in bacteria, fungi, and mammalian cells. In E. coli, and S. cerevisiae, dry density increases from stationary to exponential phase, consistent with previously known increases in the RNA/protein ratio from up-regulated ribosome production. For mammalian cells, changes in growth conditions cause substantial shifts in dry density, suggesting concurrent changes in the protein, nucleic acid and lipid content of the cell.

  11. Climatology and evolution of the mixing height over water

    Energy Technology Data Exchange (ETDEWEB)

    Sempreviva, A.M. [Istituto di Fisica dell`Atmosfera, CNR, Rome (Italy); Grynig, S.E. [Risoe National Lab., Roskilde (Denmark)

    1997-10-01

    In this paper we present results from an experimental investigation on the height of the mixed layer h, using a meteorological station located on the Danish island of Anholt. The station was operational for two years from September 1990 to October 1992. We present the analysis of two years of radio-sounding showing the average daily evolution of h. Furthermore observations of the mixed layer growth under near-neutral and unstable atmospheric conditions during six consecutive days has been modelled using a simple zero-order mixed-layer height model. Finally we have compared the evolution of the mixing height from the model with the evolution of the correlation coefficient between temperature and humidity to study the influence of the deepness of the convective layer on the mechanism of the correlation between temperature and humidity in the surface layer. (au)

  12. EFFECTS OF ALTERNATE ANTIFOAM AGENTS, NOBLE METALS, MIXING SYSTEMS AND MASS TRANSFER ON GAS HOLDUP AND RELEASE FROM NONNEWTONIAN SLURRIES

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, H; Mark Fowley, M; Charles Crawford, C; Michael Restivo, M; Robert Leishear, R

    2007-12-24

    -PJM tests and modeling being conducted at the Pacific Northwest National Laboratory (PNNL), and small-scale agitation tests and evaluations of effects waste and AFA ingredients have on gas retention and mass transfer being conducted at SRNL. Only work conducted at SRNL is reported here. Key results are: (1) The unexpected gas holdup behavior reported in 2006 for a small-scale agitation system is confirmed. The gas holdup data from small-scale and bench-scale impeller-type mixing systems reported herein show very different trends than the behavior exhibited by the prototypic sparger-PJM mixing system tested in the PNNL APEL facility. Results obtained from testing this 1/4-scale prototypic mixing system will be reported by PNNL. The reason for this difference in holdup behavior between the two different mixing systems is not known at this time. Consequently, data from the small mechanical agitation systems should not be extrapolated to prototypic plant conditions. (2) Bench-scale and small-scale tests conducted with Dow Corning 1520-US AFA show it to be a viable replacement to Dow Corning Q2-3183A AFA. This alternative AFA will, however, require significantly higher dosage (concentration) to perform the same antifoam function. (3) Addition of noble metals to the AZ-101 waste simulant does not produce a catalytic gas retention effect with the AFA. The Gas holdup is similar whether or not noble metals are present in the AZ-101 simulant. (4) Mass transfer tests were performed in a large (0.76 m diameter) bubble column filled to 1.3, 3.4, and 7.4 m elevations with water and the AZ-101 waste simulant. Mass transfer coefficients for air bubbles emanating from a prototypic 0.051 m diameter sparger were obtained from the transient decay of dissolved oxygen concentration in the initially saturated fluids. Adding AFA to water reduces the mass transfer coefficient slightly. AFA addition reduces the mass transfer coefficient for AZ-101 simulant more than it does for water because the

  13. One-Way Diffusion of Ionic Liquids in a Mixing Process with Water

    Science.gov (United States)

    Oikawa, Noriko; Tahara, Daiki; Kurita, Rei

    2016-09-01

    In contrast to the usual diffusive mixing process between two miscible liquids, the ionic liquid [Cnmim][PF6] forms a droplet in water while mixing. The droplet retains a sharp interface with surface tension, gradually decreasing in size until completely mixed with water. This peculiar behavior in the mixing process accompanies one-way diffusion, in which ions diffuse in one direction only from the bulk IL droplet into the bulk continuum of water. The activation energy of the one-way diffusion at the [Cnmim][PF6]/water interface increases with increasing length of the hydrophobic alkyl chains attached to the cation molecules of [Cnmim][PF6]. It is considered that the hydrophobic nanoscale structure observed in [C4mim][PF6] plays an important role in the generation of the droplet and the mixing dynamics.

  14. Background NO/sub x/ mixing ratios in air masses over the North Atlantic ocean

    Energy Technology Data Exchange (ETDEWEB)

    Helas, G.; Warneck, P.

    1981-08-20

    A chemiluminescence analyzer was used to measure NO/sub x/ mixing ratios at the west coast of Ireland. Two measurement modes allowed the determination of NO and NO/sub x/ = NO+NO/sub 2/. In a third mode using a molybdenum converter, higher signals were observed than was in the second mode indicating that nitrogen compounds other than NO+NO/sub 2/ are registered. They are denoted 'excess NO/sub x/'. The average NO/sub 2/ mixing ratio for a week period was 101 +- 87 pptv. In pure marine air masses identified by means of trajectory calculations, the NO/sub 2/ mixing ratios were lower and exhibited in addition a diurnal variation with nighttime values of 37 +- 6 pptv and average values of 87 +- 47 pptv. Possible origins of the diurnal variation are discussed. For such conditions, the NO mixing ratio generally was unmeasurably small, certainly less than 10 pptv. The excess NO/sub x/ is also higher during the day compared with nighttime values of about 70 pptv. Further studies are required to identify the compounds involved.

  15. Effects of temperature and mixing on polymer adjuvant migration to corn oil and water.

    Science.gov (United States)

    Limm, W; Hollifield, H C

    1995-01-01

    The effect of mixing on the migration of Irganox 1010 antioxidant from polypropylene and high-density polyethylene to water and corn oil was compared at 77, 100, and 135 degrees C. Irganox 1010 migration to water is enhanced almost five-fold by mixing at 77 degrees C, whereas at 135 degrees C, mixing has only a nominal effect on migration. Irganox 1010 migration to corn oil is virtually unaffected by mixing at the temperatures studied. Migration data indicate a similar trend for Irganox 1076.

  16. [Study on the reflected and hyperspectral mixed-pixel character of aquatic plants and water].

    Science.gov (United States)

    Sun, Tian-lin; Zhao, Yun-sheng; Liang, Ren-feng; Zhang, Xia

    2012-02-01

    A study on the reflected and hyperspectral mixed-pixel of aquatic plants and water was given by using a orthogonal experimental design with three factors and two levels. The results of F test suggest that for the single factors, the band and the area ratio of mixed-pixel on the reflected and hyperspectral mixed-pixel of the reflection effects are particularly significant, however, the detector angle had no significant effect under these experimental conditions; For the interaction, the band and the area ratio of mixed-pixel, the detector and the area ratio of mixed-pixel, the effects of these two interactions on the reflected and hyperspectral mixed-pixel are also particularly significant, This study did quantitative analysis of the factors affecting the reflected and hyperspectral mixed-pixel character and their interaction, and provided a new method for the indepth study of mixed-pixel.

  17. Mixed Inert Scalar Triplet Dark Matter, Radiative Neutrino Masses and Leptogenesis

    CERN Document Server

    Lu, Wen-Bin

    2016-01-01

    The neutral component of an inert scalar multiplet with hypercharge can provide a stable dark matter particle when its real and imaginary parts have a splitting mass spectrum. Otherwise, a tree-level dark matter-nucleon scattering mediated by the $Z$ boson will be much above the experimental limit. In this paper we focus on a mixed inert scalar triplet dark matter scenario where a complex scalar triplet with hypercharge can mix with another real scalar triplet without hypercharge through their renormalizable coupling to the standard model Higgs doublet. We consider three specified cases that carry most of the relevant features of the full parameter space: (i) the neutral component of the real triplet dominates the dark matter particle, (ii) the neutral component of the complex triplet dominates the dark matter particle; and (iii) the neutral components of the real and complex triplets equally constitute the dark matter particle. Subject to the dark matter relic abundance and direct detection constraint, we pe...

  18. A Tale of Two Timescales: Mixing, Mass Generation, and Phase Transitions in the Early Universe

    CERN Document Server

    Dienes, Keith R; Thomas, Brooks

    2015-01-01

    Light scalar fields such as axions and string moduli can play an important role in early-universe cosmology. However, many factors can significantly impact their late-time cosmological abundances. For example, in cases where the potentials for these fields are generated dynamically --- such as during cosmological mass-generating phase transitions --- the duration of the time interval required for these potentials to fully develop can have significant repercussions. Likewise, in scenarios with multiple scalars, mixing amongst the fields can also give rise to an effective timescale that modifies the resulting late-time abundances. Previous studies have focused on the effects of either the first or the second timescale in isolation. In this paper, by contrast, we examine the new features that arise from the interplay between these two timescales when both mixing and time-dependent phase transitions are introduced together. First, we find that the effects of these timescales can conspire to alter not only the tot...

  19. Impact of the first SNO results on Neutrino Mass and Mixing

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Kar, K; Choubey, Sandhya; Goswami, Srubabati; Kar, Kamales

    2001-01-01

    We investigate the implications of the SNO charged-current (CC) and electron scattering (ES) measurements of solar $^8B$ neutrino fluxes for neutrino mass and mixing parameters by performing a global and unified $\\chi^2$ analysis of the solar neutrino data incorporating the first SNO results along with the results from Cl, Ga and SuperKamiokande(SK) on the total flux of neutrinos as well as the recoil electron spectrum observed at SK and the CC spectrum observed at SNO in the framework of two neutrino mixing. We determine the best-fit values of the parameters, the $\\chi^2_{min}$ and the goodness of fit of various oscillation solutions for both $\

  20. Spatial and temporal variability in distribution of water masses in Hornsund, Spitsbergen

    Science.gov (United States)

    Promińska, Agnieszka; Falck, Eva; Walczowski, Waldemar; Sundfjord, Arild

    2016-04-01

    Arctic fjords constitute an important part of many recent investigations because this is the place where different water masses meet, mix, and transform, influencing the stability of glaciers. Hornsund, the southernmost fjord of West Spitsbergen, has been studied during the past 15 years. Observations were based primarily on high resolution measurements of water temperature and salinity along fixed sections, that have been performed every July between 2001-2015. Research carried out in years 2010 - 2015 under Polish - Norwegian projects AWAKE and AWAKE-2 allowed for expansion of the database with data covering the period from spring to autumn. During this time measurements were also conducted from a small boat in the vicinity of glaciers with a time resolution of 1-2 weeks in addition to a mooring system deployed in the fjord and on the shelf just outside Hornsund. Synthesis of our measurements give an overview of water masses observed in the fjord. From summer to summer observations reveal high variability in water temperature and salinity giving a distinct division into an area influenced by oceanic factors (Main Basin) and an area which is more influenced by local factors (Brepollen). The chronology of water mass transformation has been obtained indicating a time of transition between winter (Arctic type), additionally interrupted by temporary inflow of waters of Atlantic origin, and summer (Atlantic type) conditions.

  1. On cloud modelling and the mass accommodation coefficient of water

    Directory of Open Access Journals (Sweden)

    A. Laaksonen

    2004-11-01

    Full Text Available The mass accommodation coefficient of water is a quantity for which different experimental techniques have yielded conflicting values in the range 0.04–1. From the viewpoint of cloud modelling, this is an unfortunate situation, since the value of the mass accommodation coefficient affects the model results, e.g. the number concentration of activated cloud droplets. In this paper we argue that a mass accommodation coefficient of unity should be used in cloud modelling, since this value has been obtained in experimental studies of water droplet growth rates, a quantity which is explicitly described in cloud models. In contrast, mass accommodation coefficient values below unity have been derived from experimental results which are analyzed with different theoretical expressions than those included in cloud models.

  2. Molecular simulations of mixed self-assembled monolayer coated gold nanoparticles in water.

    Science.gov (United States)

    J, Meena Devi

    2015-06-01

    Molecular dynamics simulations have been employed to study the hydration of a series of nanoparticles, each of which was coated with a mixed self-assembled monolayer (SAM) comprising methyl- and hydroxy-terminated alkane thiol chains. The mixing ratio of those chains are different for each nanoparticle. The simulations focused on the wetting behavior of the SAM-coated gold nanoparticles and the distribution and structure of their interfacial water molecules. The interactions of the mixed SAM-coated gold nanoparticles with water were analyzed by evaluating the radial distribution function, hydrogen bonds, the dipole orientations of the water molecules, and the water residence time in the interfacial region. The wettability of the mixed SAM-coated gold nanoparticles improved as the concentration of terminal hydroxy moieties was increased. The distribution and dynamics of the interfacial water molecules were found to be influenced by the mixing ratio of the terminal moieties of the SAM chains. The results of our simulations suggest that the surface interactions of the mixed SAM-coated gold nanoparticles with the aqueous medium can be modulated by systematically altering the mixing ratio of the terminal methyl and hydroxy moieties. This work may lead to new biological and technological applications and inspire the development of novel biomimetic materials. Graphical Abstract Mixed SAM-coated gold nanoparticles.

  3. Reclamation of potable water from mixed gas streams

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, Roddie R.; Bischoff, Brian L.; Debusk, Melanie Moses; Narula, Chaitanya

    2016-07-19

    An apparatus for separating a liquid from a mixed gas stream can include a wall, a mixed gas stream passageway, and a liquid collection assembly. The wall can include a first surface, a second surface, and a plurality of capillary condensation pores. The capillary condensation pores extend through the wall, and have a first opening on the first surface of the wall, and a second opening on the second surface of the wall. The pore size of the pores can be between about 2 nm to about 100 nm. The mixed gas stream passageway can be in fluid communication with the first opening. The liquid collection assembly can collect liquid from the plurality of pores.

  4. Analysis of Mixing of Pollutants in Water Waves and Currents

    Institute of Scientific and Technical Information of China (English)

    YUAN Li-rong; SHEN Yong-ming; TANG Jun

    2007-01-01

    A vertical two-dimensional turbulence numerical model for the interaction of waves and currents is developed in the paper based on the nonlinear two-equation k-ε model with the VOF method.The one-dimensional equivalent advection velocity and equivalent mixing coefficient are defined and the solving process is introduced: The pollutant concentration field,generated by an instant source in waves and currents,is calculated with the model,and then the equivalent advection velocity and equivalent mixing coefficient are obtained by calculating the time derivative of the mean and variance of pollutant concentration probability distribution.The effects of wave period and wave height on the equivalent mixing coefficient for waves and wave-currents are also investigated.

  5. A spectral-unmixing approach to estimate water-mass concentrations in case 2 waters

    NARCIS (Netherlands)

    Burazerovic, D.; Heylen, R.; Raymaekers, D.; Knaeps, E.; Philippart, C.J.M.; Scheunders, P.

    2014-01-01

    In this work, we study the estimation of water-quality parameters from the water-leaving reflectance by means of spectral unmixing. Our starting point is the provision of an analytic model relating the reflectance of water to its masses/bodies or constituents, as specified by their specific inherent

  6. Neutrino Masses and Deviation from Tri-bimaximal mixing in \\Delta(27) model with Inverse Seesaw Mechanism

    CERN Document Server

    Abbas, M; Rashed, A; Sil, A

    2016-01-01

    We propose a scheme, based on \\Delta(27) flavor symmetry and supplemented by other discrete symmetries and inverse seesaw mechanism, where both the light neutrino masses and the deviation from tri-bimaximal mixing matrix can be linked to the source of lepton number violation. The hierarchies of the charged leptons are explained. We find that the quark masses including their hierarchies and the mixing can also be constructed in a similar way.

  7. Vector-like quarks at the origin of light quark masses and mixing

    Energy Technology Data Exchange (ETDEWEB)

    Botella, Francisco J. [Universitat de Valencia-CSIC, Departament de Fisica Teorica and IFIC, Burjassot (Spain); Branco, G.C.; Nebot, Miguel; Rebelo, M.N.; Silva-Marcos, J.I. [Universidade de Lisboa, Departamento de Fisica and Centro de Fisica Teorica de Particulas (CFTP), Instituto Superior Tecnico (IST), Lisbon (Portugal)

    2017-06-15

    We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a Z{sub 6} flavour symmetry, together with three Q = -1/3 quarks, three Q = 2/3 quarks, as well as a complex singlet scalar. The Z{sub 6} symmetry is extended to the additional fields and it is an exact symmetry of the Lagrangian, only softly broken in the scalar potential, in order to avoid the domain-wall problem. Specific examples are given and a phenomenological analysis of the main features of the model is presented. It is shown that even for vector-like quarks with masses accessible at the LHC, one can have realistic quark masses and mixing, while respecting the strict constraints on processes arising from flavour changing neutral currents. The vector-like quark decay channels are also described. (orig.)

  8. Vector-like Quarks at the Origin of Light Quark Masses and Mixing

    CERN Document Server

    Botella, Francisco J; Nebot, Miguel; Rebelo, M N; Silva-Marcos, J I

    2016-01-01

    We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a single flavour symmetry G, together with three $Q = - 1/3$ quarks, three $Q = 2/3$ quarks, as well as a complex singlet scalar. The symmetry G is extended to the additional fields and it is an exact symmetry of the Lagrangian, only spontaneously broken by the vacuum. Specific examples are given and a phenomenological analysis of the main features of the model is presented. It is shown that even for vector-like quarks with masses accessible at the LHC, one can have realistic quark masses and mixing, while respecting the strict constraints on process arising from flavour changing neutral currents (FCNC). The vector-like quark decay channels are also described.

  9. Mixed

    Directory of Open Access Journals (Sweden)

    Pau Baya

    2011-05-01

    Full Text Available Remenat (Catalan (Mixed, "revoltillo" (Scrambled in Spanish, is a dish which, in Catalunya, consists of a beaten egg cooked with vegetables or other ingredients, normally prawns or asparagus. It is delicious. Scrambled refers to the action of mixing the beaten egg with other ingredients in a pan, normally using a wooden spoon Thought is frequently an amalgam of past ideas put through a spinner and rhythmically shaken around like a cocktail until a uniform and dense paste is made. This malleable product, rather like a cake mixture can be deformed pulling it out, rolling it around, adapting its shape to the commands of one’s hands or the tool which is being used on it. In the piece Mixed, the contortion of the wood seeks to reproduce the plasticity of this slow heavy movement. Each piece lays itself on the next piece consecutively like a tongue of incandescent lava slowly advancing but with unstoppable inertia.

  10. Validation of effective momentum and heat flux models for stratification and mixing in a water pool

    Energy Technology Data Exchange (ETDEWEB)

    Hua Li; Villanueva, W.; Kudinov, P. [Royal Institute of Technology (KTH), Div. of Nuclear Power Safety, Stockholm (Sweden)

    2013-06-15

    The pressure suppression pool is the most important feature of the pressure suppression system in a Boiling Water Reactor (BWR) that acts primarily as a passive heat sink during a loss of coolant accident (LOCA) or when the reactor is isolated from the main heat sink. The steam injection into the pool through the blowdown pipes can lead to short term dynamic phenomena and long term thermal transient in the pool. The development of thermal stratification or mixing in the pool is a transient phenomenon that can influence the pool's pressure suppression capacity. Different condensation regimes depending on the pool's bulk temperature and steam flow rates determine the onset of thermal stratification or erosion of stratified layers. Previously, we have proposed to model the effect of steam injection on the mixing and stratification with the Effective Heat Source (EHS) and the Effective Momentum Source (EMS) models. The EHS model is used to provide thermal effect of steam injection on the pool, preserving heat and mass balance. The EMS model is used to simulate momentum induced by steam injection in different flow regimes. The EMS model is based on the combination of (i) synthetic jet theory, which predicts effective momentum if amplitude and frequency of flow oscillations in the pipe are given, and (ii) model proposed by Aya and Nariai for prediction of the amplitude and frequency of oscillations at a given pool temperature and steam mass flux. The complete EHS/EMS models only require the steam mass flux, initial pool bulk temperature, and design-specific parameters, to predict thermal stratification and mixing in a pressure suppression pool. In this work we use EHS/EMS models implemented in containment thermal hydraulic code GOTHIC. The PPOOLEX experiments (Lappeenranta University of Technology, Finland) are utilized to (a) quantify errors due to GOTHIC's physical models and numerical schemes, (b) propose necessary improvements in GOTHIC sub-grid scale

  11. Three Dimensional Baroclinic Numerical Model for Simulating Fresh and Salt Water Mixing in the Yangtze Estuary

    Institute of Scientific and Technical Information of China (English)

    郑金海; 严以新; 诸裕良

    2002-01-01

    For simulating fresh and salt water mixing in estuaries, a three dimensional nonlinear baroclinic numerical model isdeveloped, in which the gradients of horizontal pressure contain the gradient of barotropic pressure arising from the gradi-ent of tidal level and the gradient of baroclinic pressure due to the gradient of salinity. The Eulerian-Lagrangian method isemployed to descretize both the momentum equations of tidal motion and the equation of salt water diffusion so as to im-prove the computational stability and accuracy. The methods to provide the boundary conditions and the initial conditionsare proposed, and the criterion for computational stability of the salinity fields is presented. The present model is used formodeling fresh and salt water mixing in the Yangtze Estuary. Computations show that the salinity distribution has thecharacteristics of partial mixing pattern, and that the present model is suitable for simulation of fresh and salt water mixing in the Yangtze Estuary.

  12. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    Science.gov (United States)

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-08-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra, we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres were obtained in selected solvents with smaller Ra values: methanol/water, ethanol/water and 2-propanol/water. In addition, the mixed solvent with smaller Ra values gave a higher conversion of dopamine. The strategy for mixed solvent selection is might be useful to choose optimal reaction media for efficient chemical synthesis.

  13. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    Science.gov (United States)

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-01-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra, we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres were obtained in selected solvents with smaller Ra values: methanol/water, ethanol/water and 2-propanol/water. In addition, the mixed solvent with smaller Ravalues gave a higher conversion of dopamine. The strategy for mixed solvent selection is might be useful to choose optimal reaction media for efficient chemical synthesis. PMID:25317902

  14. Characterisation of Swift Heavy Ion-induced Mixing using Secondary Ion Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    B. R. Chakraborty

    2009-07-01

    Full Text Available Swift heavy ions of Au at 120 MeV are irradiated at the interface of Si/Me/Si (Me=V,Fe,Co and the behaviour of mixing examined wrt to different ion doses. The fluences were varied from 1x1013 ions/cm2 to 1x1014 ions/cm2 on the multilayers of Si/Me/Se (Me=V,Fe,Co and the interface of Si/Me(Me=V,Fe,Co were characterised using Rutherford backscattering spectroscopy(RBS and secondary ion mass spectrometry (SIMS. The atomic mixing width was found to be increasing monotonically with ion fluence in all the three cases,. The mixing rate and efficiency calculations were made and the diffusivity values thus obtained suggested a transient melt phase at the interface according to thermal spike model. In case of Me=Co, it was further probed with XRD and Raman spectroscopy to confirm the formation of cobalt silicides even at room temperature.Defence Science Journal, 2009, 59(4, pp.356-362, DOI:http://dx.doi.org/10.14429/dsj.59.1534

  15. Discovery of Three Pulsating, Mixed-atmosphere, Extremely Low-mass White Dwarf Precursors

    Science.gov (United States)

    Gianninas, A.; Curd, Brandon; Fontaine, G.; Brown, Warren R.; Kilic, Mukremin

    2016-05-01

    We report the discovery of pulsations in three mixed-atmosphere, extremely low-mass white dwarf (ELM WD, M ≤slant 0.3 M ⊙) precursors. Following the recent discoveries of pulsations in both ELM and pre-ELM WDs, we targeted pre-ELM WDs with mixed H/He atmospheres with high-speed photometry. We find significant optical variability in all three observed targets with periods in the range 320-590 s, consistent in timescale with theoretical predictions of p-mode pulsations in mixed-atmosphere ≈0.18 M ⊙ He-core pre-ELM WDs. This represents the first empirical evidence that pulsations in pre-ELM WDs can only occur if a significant amount of He is present in the atmosphere. Future, more extensive, timeseries photometry of the brightest of the three new pulsators offers an excellent opportunity to constrain the thickness of the surface H layer, which regulates the cooling timescales for ELM WDs. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).

  16. Discovery of Three Pulsating, Mixed Atmosphere, Extremely Low-Mass White Dwarf Precursors

    CERN Document Server

    Gianninas, A; Fontaine, G; Browm, Warren R; Kilic, Mukremin

    2016-01-01

    We report the discovery of pulsations in three mixed atmosphere, extremely low-mass white dwarf (ELM WD, M $<$ 0.3 M$_{\\odot}$) precursors. Following the recent discoveries of pulsations in both ELM and pre-ELM WDs, we targeted pre-ELM WDs with mixed H/He atmospheres with high-speed photometry. We find significant optical variability in all three observed targets with periods in the range 320--590 s, consistent in time-scale with theoretical predictions of p-mode pulsations in mixed-atmosphere $\\approx$ 0.18 M$_{\\odot}$ He-core pre-ELM WDs. This represents the first empirical evidence that pulsations in pre-ELM WDs can only occur if a significant amount of He is present in the atmosphere. Future, more extensive, time-series photometry of the brightest of the three new pulsators offers an excellent opportunity to constrain the thickness of the surface H layer which regulates the cooling timescales for ELM WDs.

  17. Observed trends of anthropogenic acidification in North Atlantic water masses

    Directory of Open Access Journals (Sweden)

    M. Vázquez-Rodríguez

    2012-03-01

    Full Text Available The lack of observational pH data has made difficult assessing recent rates of ocean acidification, particularly in the high latitudes. Here we present a time series of high-quality carbon system measurements in the North Atlantic, comprising fourteen cruises spanning over 27 yr (1981–2008 and covering important water mass formation areas like the Irminger and Iceland basins. We provide direct quantification of anthropogenic acidification rates in upper and intermediate North Atlantic waters by removing the natural variability of pH from the observations. Bottle data were normalised to basin-average conditions using climatological data and further condensed into averages per water mass and year to examine the temporal trends. The highest acidification rates of all inspected water masses were associated with surface waters in the Irminger Sea (−0.0018 ± 0.0001 yr−1 and the Iceland Basin (−0.0012 ± 0.0002 yr−1 and, unexpectedly, with Labrador Seawater (LSW which experienced an unprecedented pH drop of −0.0015 ± 0.001 yr−1. The latter stems from the formation by deep convection and the rapid propagation in the North Atlantic subpolar gyre of this well-ventilated water mass. The high concentrations of anthropogenic CO2 are effectively transported from the surface into intermediate waters faster than via downward diffusion, thus accelerating the acidification rates of LSW. An extrapolation of the observed lineal trends of acidification suggests that the pH of LSW could drop 0.45 units with respect to pre-industrial levels by the time atmospheric CO2 concentrations double the present ones.

  18. A metabolism perspective on alternative urban water servicing options using water mass balance.

    Science.gov (United States)

    Farooqui, Tauheed A; Renouf, Marguerite A; Kenway, Steven J

    2016-12-01

    Urban areas will need to pursue new water servicing options to ensure local supply security. Decisions about how best to employ them are not straightforward due to multiple considerations and the potential for problem shifting among them. We hypothesise that urban water metabolism evaluation based a water mass balance can help address this, and explore the utility of this perspective and the new insights it provides about water servicing options. Using a water mass balance evaluation framework, which considers direct urban water flows (both 'natural' hydrological and 'anthropogenic' flows), as well as water-related energy, we evaluated how the use of alternative water sources (stormwater/rainwater harvesting, wastewater/greywater recycling) at different scales influences the 'local water metabolism' of a case study urban development. New indicators were devised to represent the water-related 'resource efficiency' and 'hydrological performance' of the urban area. The new insights gained were the extent to which alternative water supplies influence the water efficiency and hydrological performance of the urban area, and the potential energy trade-offs. The novel contribution is the development of new indicators of urban water resource performance that bring together considerations of both the 'anthropogenic' and 'natural' water cycles, and the interactions between them. These are used for the first time to test alternative water servicing scenarios, and to provide a new perspective to complement broader sustainability assessments of urban water.

  19. Probing the turbulent mixing strength in protoplanetary disks across the stellar mass range: no significant variations

    CERN Document Server

    Mulders, Gijs D

    2012-01-01

    Dust settling and grain growth are the first steps in the planet-formation process in protoplanetary disks. These disks are observed around stars with different spectral types, and there are indications that the disks around lower mass stars are significantly flatter, which could indicate that they settle and evolve faster, or in a different way. We aim to test this assumption by modeling the median spectral energy distributions (SEDs) of three samples of protoplanetary disks: around Herbig stars, T Tauri stars and brown dwarfs. We focus on the turbulent mixing strength to avoid a strong observational bias from disk and stellar properties that depend on stellar mass. We generated SEDs with the radiative transfer code MCMax, using a hydrostatic disk structure and settling the dust in a self-consistent way with the alpha-prescription to probe the turbulent mixing strength. We are able to fit all three samples with a disk with the same input parameters, scaling the inner edge to the dust evaporation radius and d...

  20. The influence of the surface composition of mixed monolayer films on the evaporation coefficient of water.

    Science.gov (United States)

    Miles, Rachael E H; Davies, James F; Reid, Jonathan P

    2016-07-20

    We explore the dependence of the evaporation coefficient of water from aqueous droplets on the composition of a surface film, considering in particular the influence of monolayer mixed component films on the evaporative mass flux. Measurements with binary component films formed from long chain alcohols, specifically tridecanol (C13H27OH) and pentadecanol (C15H31OH), and tetradecanol (C14H29OH) and hexadecanol (C16H33OH), show that the evaporation coefficient is dependent on the mole fractions of the two components forming the monolayer film. Immediately at the point of film formation and commensurate reduction in droplet evaporation rate, the evaporation coefficient is equal to a mole fraction weighted average of the evaporation coefficients through the equivalent single component films. As a droplet continues to diminish in surface area with continued loss of water, the more-soluble, shorter alkyl chain component preferentially partitions into the droplet bulk with the evaporation coefficient tending towards that through a single component film formed simply from the less-soluble, longer chain alcohol. We also show that the addition of a long chain alcohol to an aqueous-sucrose droplet can facilitate control over the degree of dehydration achieved during evaporation. After undergoing rapid gas-phase diffusion limited water evaporation, binary aqueous-sucrose droplets show a continued slow evaporative flux that is limited by slow diffusional mass transport within the particle bulk due to the rapidly increasing particle viscosity and strong concentration gradients that are established. The addition of a long chain alcohol to the droplet is shown to slow the initial rate of water loss, leading to a droplet composition that remains more homogeneous for a longer period of time. When the sucrose concentration has achieved a sufficiently high value, and the diffusion constant of water has decreased accordingly so that bulk phase diffusion arrest occurs in the monolayer

  1. Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high-resolution mass spectrometry

    KAUST Repository

    Sioud, Salim

    2012-05-04

    RATIONALE To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water-soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored. METHODS A multicomponent mixed dopant for non-targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high-resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated. RESULTS Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2- to 10-fold for the tested PAHs compared to those obtained with pure chlorobenzene. CONCLUSIONS A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high-resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/;μL levels within a 5 min run time with high mass accuracy a;circ4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.

  2. Quark mass and mixing in the 3-3-1 model with neutral leptons based on $D_4$ flavor symmetr

    CERN Document Server

    Vien, V V

    2014-01-01

    The $D_4$ flavor model based on $\\mathrm{SU}(3)_C \\otimes \\mathrm{SU}(3)_L \\otimes \\mathrm{U}(1)_X$ gauge symmetry is updated in which the quark mixing matrix is concentrated. After spontaneous breaking of flavor symmetry, with the constraint on Higgs VEVs in the Yukawa couplings, all of quarks have consistent masses and a small deviation from the unity is obtained at the tree-level. To obtain the quark mixing matrix consistent with experimental data in 2012, the violation terms with $\\underline{1}'$ under $D_4$ are introduced. The realistic quark mass and mixing are derived.

  3. Selective mixed-bed solid phase extraction of atrazine herbicide from environmental water samples using molecularly imprinted polymer.

    Science.gov (United States)

    Zarejousheghani, Mashaalah; Fiedler, Petra; Möder, Monika; Borsdorf, Helko

    2014-11-01

    A novel approach for the selective extraction of organic target compounds from water samples has been developed using a mixed-bed solid phase extraction (mixed-bed SPE) technique. The molecularly imprinted polymer (MIP) particles are embedded in a network of silica gel to form a stable uniform porous bed. The capabilities of this method are demonstrated using atrazine as a model compound. In comparison to conventional molecularly imprinted-solid phase extraction (MISPE), the proposed mixed-bed MISPE method in combination with gas chromatography-mass spectrometry (GC-MS) analysis enables more reproducible and efficient extraction performance. After optimization of operational parameters (polymerization conditions, bed matrix ingredients, polymer to silica gel ratio, pH of the sample solution, breakthrough volume plus washing and elution conditions), improved LODs (1.34 µg L(-1) in comparison to 2.25 µg L(-1) obtained using MISPE) and limits of quantification (4.5 µg L(-1) for mixed-bed MISPE and 7.5 µg L(-1) for MISPE) were observed for the analysis of atrazine. Furthermore, the relative standard deviations (RSDs) for atrazine at concentrations between 5 and 200 µg L(-1) ranged between 1.8% and 6.3% compared to MISPE (3.5-12.1%). Additionally, the column-to-column reproducibility for the mixed-bed MISPE was significantly improved to 16.1%, compared with 53% that was observed for MISPE. Due to the reduced bed-mass sorbent and at optimized conditions, the total amount of organic solvents required for conditioning, washing and elution steps reduced from more than 25 mL for conventional MISPE to less than 2 mL for mixed-bed MISPE. Besides reduced organic solvent consumption, total sample preparation time of the mixed-bed MISPE method relative to the conventional MISPE was reduced from more than 20 min to less than 10 min. The amount of organic solvent required for complete elution diminished from 3 mL (conventional MISPE) to less than 0.4 mL with the mixed

  4. Experimental testing and modeling analysis of solute mixing at water distribution pipe junctions.

    Science.gov (United States)

    Shao, Yu; Jeffrey Yang, Y; Jiang, Lijie; Yu, Tingchao; Shen, Cheng

    2014-06-01

    Flow dynamics at a pipe junction controls particle trajectories, solute mixing and concentrations in downstream pipes. The effect can lead to different outcomes of water quality modeling and, hence, drinking water management in a distribution network. Here we have investigated solute mixing behavior in pipe junctions of five hydraulic types, for which flow distribution factors and analytical equations for network modeling are proposed. First, based on experiments, the degree of mixing at a cross is found to be a function of flow momentum ratio that defines a junction flow distribution pattern and the degree of departure from complete mixing. Corresponding analytical solutions are also validated using computational-fluid-dynamics (CFD) simulations. Second, the analytical mixing model is further extended to double-Tee junctions. Correspondingly the flow distribution factor is modified to account for hydraulic departure from a cross configuration. For a double-Tee(A) junction, CFD simulations show that the solute mixing depends on flow momentum ratio and connection pipe length, whereas the mixing at double-Tee(B) is well represented by two independent single-Tee junctions with a potential water stagnation zone in between. Notably, double-Tee junctions differ significantly from a cross in solute mixing and transport. However, it is noted that these pipe connections are widely, but incorrectly, simplified as cross junctions of assumed complete solute mixing in network skeletonization and water quality modeling. For the studied pipe junction types, analytical solutions are proposed to characterize the incomplete mixing and hence may allow better water quality simulation in a distribution network. Published by Elsevier Ltd.

  5. Sneutrino Mixing

    OpenAIRE

    Grossman, Yuval

    1997-01-01

    In supersymmetric models with nonvanishing Majorana neutrino masses, the sneutrino and antisneutrino mix. The conditions under which this mixing is experimentally observable are studied, and mass-splitting of the sneutrino mass eigenstates and sneutrino oscillation phenomena are analyzed.

  6. Numerical study of surface water waves generated by mass movement

    Energy Technology Data Exchange (ETDEWEB)

    Ghozlani, Belgacem; Hafsia, Zouhaier; Maalel, Khlifa, E-mail: ghozlanib@yahoo.fr [Ecole Nationale d' Ingenieurs de Tunis, Laboratoire de Modelisation en ' Hydraulique et Environnement, BP 37, Le Belvedere, 1002 Tunis (Tunisia)

    2013-10-01

    In this paper waves generated by two-dimensional mass movement are simulated using a numerical model based on the full hydrodynamic coupling between rigid-body motion and ambient fluid flow. This approach has the capability to represent the dynamics of the moving rigid body, which avoids the need to prescribe the body velocity based on the data measurements. This model is implemented in the CFX code and uses the Reynolds average Navier-Stokes equations solver coupled to the recently developed immersed solid technique. The latter technique allows us to follow implicitly the motion of the solid block based on the rigid body solver. The volume-of-fluid method is used to track the free surface locations. The accuracy of the present model is firstly examined against the simple physical case of a freely falling rigid body into water reproducing Scott Russell's solitary waves. More complex and realistic simulations of aerial and submarine mass-movement, simulated by a rigid wedge sliding into water along a 45 Degree-Sign slope, are then performed. Simulated results of the aerial mass movement show the complex flow patterns in terms of the velocity fields and free surface profiles. Results are in good agreement with the available experimental data. In addition, the physical processes associated with the generation of water wave by two-dimensional submarine mass-movement are explored. The effects of the initial submergence and specific gravity on the slide mass kinematics and maximum wave amplitude are investigated. The terminal velocity and initial acceleration of the slide mass are well predicted when compared to experimental results. It is found that the initial submergence did not have a significant effect on the initial acceleration of the slide block centre of mass. However, it depends nonlinearly on the specific gravity. The maximum wave amplitude and the time at which it occurred are also presented as a function of the initial submergence and specific gravity

  7. Numerical study of surface water waves generated by mass movement

    Science.gov (United States)

    Ghozlani, Belgacem; Hafsia, Zouhaier; Maalel, Khlifa

    2013-10-01

    In this paper waves generated by two-dimensional mass movement are simulated using a numerical model based on the full hydrodynamic coupling between rigid-body motion and ambient fluid flow. This approach has the capability to represent the dynamics of the moving rigid body, which avoids the need to prescribe the body velocity based on the data measurements. This model is implemented in the CFX code and uses the Reynolds average Navier-Stokes equations solver coupled to the recently developed immersed solid technique. The latter technique allows us to follow implicitly the motion of the solid block based on the rigid body solver. The volume-of-fluid method is used to track the free surface locations. The accuracy of the present model is firstly examined against the simple physical case of a freely falling rigid body into water reproducing Scott Russell's solitary waves. More complex and realistic simulations of aerial and submarine mass-movement, simulated by a rigid wedge sliding into water along a 45° slope, are then performed. Simulated results of the aerial mass movement show the complex flow patterns in terms of the velocity fields and free surface profiles. Results are in good agreement with the available experimental data. In addition, the physical processes associated with the generation of water wave by two-dimensional submarine mass-movement are explored. The effects of the initial submergence and specific gravity on the slide mass kinematics and maximum wave amplitude are investigated. The terminal velocity and initial acceleration of the slide mass are well predicted when compared to experimental results. It is found that the initial submergence did not have a significant effect on the initial acceleration of the slide block centre of mass. However, it depends nonlinearly\\vadjust{\

  8. Structure and dynamics of water in mixed solutions including laponite and PEO

    Science.gov (United States)

    Morikubo, Satoshi; Sekine, Yurina; Ikeda-Fukazawa, Tomoko

    2011-01-01

    To investigate the structure and dynamics of water in mixed solutions including laponite clay particles and poly(ethylene oxide) (PEO), we measured the Raman spectra of the mixed solutions in the temperature range 283-313 K. The results show that the vibrational energies of the O-H stretching modes in the mixed solutions depend on the water content and temperature. The energy shifts of the O-H stretching modes are attributed to changes in the water structure. By applying a structural model of bulk water to the spectra in the O-H stretching region, the local structures of water in the solutions were analyzed. The result shows that the formation probability of hydrogen bonds in the solutions decreases as the water content decreases. Laponite and PEO have effects to disrupt the network structure of hydrogen bonds between water molecules. Further, it was found that laponite and PEO cause increase in the strength of hydrogen bonds of surrounding water,although the strength of the hydrogen bonds increases with the order water-laponite laponite-PEO mixed solutions has a less-networked structure with strong hydrogen bonds compared with bulk water.

  9. Mixing water ice into regolith in low-velocity impact experiments

    Science.gov (United States)

    Brisset, J.; Colwell, J. E.; Dove, A.; Rascon, A. N.; Mohammed, N.; Cox, C.

    2016-12-01

    Collisions between dust and ice grains of different sizes lead to particle growth both in Saturn's rings and in the protoplanetary disk (PPD). Low-velocity collisions (a few m/s or less) among ring or PPD particles produce ejecta and play an important role in this growth process as ejected particles accrete on larger grains. We report on the results of a series of experiments to study the ejecta mass-velocity distribution from impacts of cm-scale particles into granular media at speeds below 3 m/s. These experiments were performed using the lunar regolith simulant JSC-1 in both microgravity and 1-g conditions, under vacuum and at room temperature. As most planetesimal formation occurred beyond the frost line and as Satrun's rings particles are mostly composed of water ice, we proceeded to perform impact experiments at 1-g into JSC-1 lunar regolith simulant mixed with water ice particles at low temperatures (ring particle collisions as well as planetesimal formation.

  10. Power Consumption, Mixing Time, and Oxygen Mass Transfer in a Gas-Liquid Contactor Stirred with a Dual Impeller for Different Spacing

    Directory of Open Access Journals (Sweden)

    Hayder Mohammed Issa

    2016-01-01

    Full Text Available Multiple or dual impellers are widely implemented in stirred contactors used in various biological processes like fermentation, water treatment, and pharmaceutical production. The spacing between impellers is considered as a crucial factor in designing of these types of contactors resulting in variation of oxygen mass transfer, mixing time, or power consumption for such biological system. A study of three parts was conducted to characterize the effect of the spacing between impellers on the most important parameters that related to biological contactor performance: oxygen mass transfer coefficient kla from the gas phase (air to the liquid phase (water, mixing time, and power consumption for different operating rotational speeds (1.67–3.33 rps and for three different spacing positions. The used impellers system in the study is a dual impeller system which consists of an inverted and bladed rotated cone (IBRC and a pitched-blade up-flow propeller (PBPU. The experimental results showed that the shorter spacing (the lower PBPU in a higher position is more convenient, as the achieved oxygen mass transfer coefficient has showed an improvement in its values with lower mixing time and with a slight alteration in power consumption.

  11. Numerical simulations of lab-scale brine-water mixing experiments.

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, Imane; Webb, Stephen Walter

    2006-10-01

    Laboratory-scale experiments simulating the injection of fresh water into brine in a Strategic Petroleum Reserve (SPR) cavern were performed at Sandia National Laboratories for various conditions of injection rate and small and large injection tube diameters. The computational fluid dynamic (CFD) code FLUENT was used to simulate these experiments to evaluate the predictive capability of FLUENT for brine-water mixing in an SPR cavern. The data-model comparisons show that FLUENT simulations predict the mixing plume depth reasonably well. Predictions of the near-wall brine concentrations compare very well with the experimental data. The simulated time for the mixing plume to reach the vessel wall was underpredicted for the small injection tubes but reasonable for the large injection tubes. The difference in the time to reach the wall is probably due to the three-dimensional nature of the mixing plume as it spreads out at the air-brine or oil-brine interface. The depth of the mixing plume as it spreads out along the interface was within a factor of 2 of the experimental data. The FLUENT simulation results predict the plume mixing accurately, especially the water concentration when the mixing plume reaches the wall. This parameter value is the most significant feature of the mixing process because it will determine the amount of enhanced leaching at the oil-brine interface.

  12. Modeling water emission from low-mass protostellar envelopes

    CERN Document Server

    van Kempen, T A; Van Dishoeck, E F; Hogerheijde, M R; Jørgensen, J K

    2008-01-01

    Within low-mass star formation, water vapor plays a key role in the chemistry and energy balance of the circumstellar material. The Herschel Space Observatory will open up the possibility to observe water lines originating from a wide range of excitation energies.Our aim is to simulate the emission of rotational water lines from envelopes characteristic of embedded low-mass protostars. A large number of parameters that influence the water line emission are explored: luminosity, density,density slope and water abundances.Both dust and water emission are modelled using full radiative transfer in spherical symmetry. The temperature profile is calculated for a given density profile. The H2O level populations and emission profiles are in turn computed with a non-LTE line code. The results are analyzed to determine the diagnostic value of different lines, and are compared with existing observations. Lines can be categorized in: (i) optically thick lines, including ground-state lines, mostly sensitive to the cold ou...

  13. Terrestrial planets and water delivery around low-mass stars

    Science.gov (United States)

    Dugaro, A.; de Elía, G. C.; Brunini, A.; Guilera, O. M.

    2016-11-01

    Context. Theoretical and observational studies suggest that protoplanetary disks with a wide range of masses could be found around low-mass stars. Aims: We analyze planetary formation processes in systems without gas giants around M3- and M0-type stars of 0.29 M⊙ and 0.5 M⊙, respectively. In particular, we assume disks with masses of 5% and 10% of the mass of the star. Our study focuses on the formation of terrestrial-like planets and water delivery in the habitable zone (HZ). Methods: First, we use a semi-analytical model to describe the evolution of embryos and planetesimals during the gaseous phase. Then, a N-body code is used to analyze the last giant impact phase after the gas dissipation. Results: For M3-type stars, five planets with different properties are formed in the HZ. These planets have masses of 0.072 M⊕, 0.13 M⊕ (two of them), and 1.03 M⊕, and have water contents of 5.9%, 16.7%, 28.6%, and 60.6% by mass, respectively. Then, the fifth planet formed in the HZ is a dry world with 0.138 M⊕. For M0-type stars, four planets are produced in the HZ with masses of 0.28 M⊕, 0.51 M⊕, 0.72 M⊕, and 1.42 M⊕, and they have water contents of 26.7%, 45.8%, 68%, and 50.5% by mass, respectively. Conclusions: M3- and M0-type stars represent targets of interest for the search of exoplanets in the HZ. In fact, the Mars-mass planets formed around M3-type stars could maintain habitable conditions in their early histories. Thus, the search for candidates around young M3-type stars could lead to the detection of planets analogous to early Mars. Moreover, Earth-mass planets should also be discovered around M3-type stars and, sub- and super-Earths should be detected around M0-type stars. Such planets are very interesting since they could maintain habitable conditions for very long.

  14. Source zone remediation by ZVI-clay soil-mixing: Reduction of tetrachloroethene mass and mass discharge at a Danish DNAPL site

    DEFF Research Database (Denmark)

    Fjordbøge, Annika Sidelmann; Lange, Ida Vedel; Binning, Philip John;

    2012-01-01

    and mass discharge is obtained. The technology was tested at a Danish DNAPL site, where the secondary aquifer was heavily contaminated by tetrachloroethene (PCE). ZVI-Clay soil-mixing was tested at a small source zone (~200 m3) with soil concentrations ranging up to 12,000 mg/kg. The objective of the field...... test was to document in situ destruction of the contaminant mass and the down-gradient response in contaminant mass discharge. The field sampling consisted of baseline measurements and a 19-month monitoring program (7 sampling campaigns) subsequent to the implementation of ZVI-Clay soil mixing...... in magnitude) with ethene as the main degradation product. The down-gradient reduction of contaminant mass discharge occurred more slowly; after 19 months a mass discharge reduction of 76 % was obtained for PCE. However, due to a temporary increase in cis-DCE, the overall down-gradient reduction of all...

  15. Charged Fermion Masses and Mixing from a SU(3) Family Symmetry Model

    CERN Document Server

    Hernandez-Galeana, Albino

    2016-01-01

    Within the framework of a Beyond Standard Model (BSM) with a local $SU(3)$ family symmetry, we report an updated fit of parameters which account for the known spectrum of quarks and charged lepton masses and the quark mixing in a $4\\times 4$ non-unitary $V_{CKM}$. In this scenario, ordinary heavy fermions, top and bottom quarks and tau lepton, become massive at tree level from Dirac See-saw mechanisms implemented by the introduction of a new set of $SU(2)_L$ weak singlet vector-like fermions, $U,D,E,N$, with $N$ a sterile neutrino. The $N_{L,R}$ sterile neutrinos allow the implementation of a $8\\times 8$ general See-saw Majorana neutrino mass matrix with four massless eigenvalues at tree level. Hence, light fermions, including neutrinos, obtain masses from loop radiative corrections mediated by the massive $SU(3)$ gauge bosons. $SU(3)$ family symmetry is broken spontaneously in two stages, whose hierarchy of scales yield an approximate $SU(2)$ global symmetry associated with the $Z_1, Y_1^\\pm$ gauge boson mas...

  16. Mixing it up: Corals take an active role in mass transport

    Science.gov (United States)

    Fernandez, Vicente; Shapiro, Orr; Brumley, Douglas; Garren, Melissa; Guasto, Jeffrey; Kramarski-Winter, Esti; Vardi, Assaf; Stocker, Roman

    2014-11-01

    The growth and health of reef-building corals are limited by corals' ability to exchange nutrients and oxygen with the surrounding, sometimes quiescent, seawater. Mass transport in coral systems has long been considered to occur passively as a result of molecular diffusion and the ambient fluid flow over the coral. Through a combination of microscale visualization experiments and numerical modeling, we demonstrate instead that motile cilia densely covering the coral surface - previously thought to serve cleaning and feeding purposes- actively stir the coral boundary layer by generating persistent vortices above the coral surface. This active mixing was observed over a variety of corals with differing surface geometries. We have quantified the contribution of ciliary surface vortices to mass transport, finding oxygen flux enhancements of 2 to 3 orders of magnitude under environmentally relevant ambient flow conditions. These results reveal a new, active role of the coral animal in regulating its mass transport by engineering its local hydrodynamic environment, an ability that may have an important role in the evolutionary success of reef corals.

  17. Robust automated mass spectra interpretation and chemical formula calculation using mixed integer linear programming.

    Science.gov (United States)

    Baran, Richard; Northen, Trent R

    2013-10-15

    Untargeted metabolite profiling using liquid chromatography and mass spectrometry coupled via electrospray ionization is a powerful tool for the discovery of novel natural products, metabolic capabilities, and biomarkers. However, the elucidation of the identities of uncharacterized metabolites from spectral features remains challenging. A critical step in the metabolite identification workflow is the assignment of redundant spectral features (adducts, fragments, multimers) and calculation of the underlying chemical formula. Inspection of the data by experts using computational tools solving partial problems (e.g., chemical formula calculation for individual ions) can be performed to disambiguate alternative solutions and provide reliable results. However, manual curation is tedious and not readily scalable or standardized. Here we describe an automated procedure for the robust automated mass spectra interpretation and chemical formula calculation using mixed integer linear programming optimization (RAMSI). Chemical rules among related ions are expressed as linear constraints and both the spectra interpretation and chemical formula calculation are performed in a single optimization step. This approach is unbiased in that it does not require predefined sets of neutral losses and positive and negative polarity spectra can be combined in a single optimization. The procedure was evaluated with 30 experimental mass spectra and was found to effectively identify the protonated or deprotonated molecule ([M + H](+) or [M - H](-)) while being robust to the presence of background ions. RAMSI provides a much-needed standardized tool for interpreting ions for subsequent identification in untargeted metabolomics workflows.

  18. Groundwater-Surface Water Mixing Shifts Ecological Assembly Processes and Stimulates Organic Carbon Turnover

    Science.gov (United States)

    Stegen, J.; Fredrickson, J.; Wilkins, M.; Konopka, A.; Nelson, W.; Arntzen, E.; Chrisler, W.; Chu, R. K.; Danczak, B.; Fansler, S.; Kennedy, D.; Resch, T.; Tfaily, M. M.

    2015-12-01

    Environmental transitions often result in resource mixtures that overcome limitations to microbial metabolism, resulting in biogeochemical hot spots and moments. Riverine systems where groundwater mixes with surface water (the hyporheic zone) are spatially complex and temporally dynamic, making development of predictive models challenging. Spatial and temporal variations in hyporheic zone microbial communities are a key, but understudied, component of riverine biogeochemical function. To investigate the coupling among groundwater-surface water mixing, microbial communities, and biogeochemistry we applied ecological theory, aqueous biogeochemistry, DNA sequencing, and ultra-high resolution organic carbon profiling to field samples collected across times and locations representing a broad range of mixing conditions. Our results indicate that groundwater-surface water mixing in the hyporheic zone simultaneously (i) stimulated heterotrophic respiration, (ii) altered organic carbon composition, (iii) caused ecological processes to shift from stochastic to deterministic, and (iv) selected for microbial taxa capable of degrading a broad suite of organic compounds.

  19. MIXED FINITE ELEMENT METHODS FOR THE SHALLOW WATER EQUATIONS INCLUDING CURRENT AND SILT SEDIMENTATION ( Ⅱ )-THE DISCRETE-TIME CASE ALONG CHARACTERISTICS

    Institute of Scientific and Technical Information of China (English)

    罗振东; 朱江; 曾庆存; 谢正辉

    2004-01-01

    The mixed finite element (MFE) methods for a shallow water equation system consisting of water dynamics equations, silt transport equation, and the equation of bottom topography change were derived. A fully discrete MFE scheme for the discrete-time along characteristics is presented and error estimates are established. The existence and convergence of MFE solution of the discrete current velocity, elevation of the bottom topography, thickness of fluid column, and mass rate of sediment is demonstrated.

  20. Decadal acidification in the water masses of the Atlantic Ocean.

    Science.gov (United States)

    Ríos, Aida F; Resplandy, Laure; García-Ibáñez, Maribel I; Fajar, Noelia M; Velo, Anton; Padin, Xose A; Wanninkhof, Rik; Steinfeldt, Reiner; Rosón, Gabriel; Pérez, Fiz F

    2015-08-11

    Global ocean acidification is caused primarily by the ocean's uptake of CO2 as a consequence of increasing atmospheric CO2 levels. We present observations of the oceanic decrease in pH at the basin scale (50 °S-36 °N) for the Atlantic Ocean over two decades (1993-2013). Changes in pH associated with the uptake of anthropogenic CO2 (ΔpHCant) and with variations caused by biological activity and ocean circulation (ΔpHNat) are evaluated for different water masses. Output from an Institut Pierre Simon Laplace climate model is used to place the results into a longer-term perspective and to elucidate the mechanisms responsible for pH change. The largest decreases in pH (∆pH) were observed in central, mode, and intermediate waters, with a maximum ΔpH value in South Atlantic Central Waters of -0.042 ± 0.003. The ΔpH trended toward zero in deep and bottom waters. Observations and model results show that pH changes generally are dominated by the anthropogenic component, which accounts for rates between -0.0015 and -0.0020/y in the central waters. The anthropogenic and natural components are of the same order of magnitude and reinforce one another in mode and intermediate waters over the time period. Large negative ΔpHNat values observed in mode and intermediate waters are driven primarily by changes in CO2 content and are consistent with (i) a poleward shift of the formation region during the positive phase of the Southern Annular Mode in the South Atlantic and (ii) an increase in the rate of the water mass formation in the North Atlantic.

  1. Dianeutral mixing, transformation and transport of the deep water of the Indian Ocean

    Science.gov (United States)

    You, Yuzhu

    1999-01-01

    The realization of North Atlantic Deep Water (NADW) replacement in the deep northern Indian Ocean is crucial to the "conveyor belt" scheme. This was investigated with the updated 1994 Levitus climatological atlas. The study was performed on four selected neutral surfaces, encompassing the Indian deep water from 2000 to 3500 m. The Indian deep water comprises three major water masses: NADW, Circumpolar Deep Water (CDW) and North Indian Deep Water (NIDW). Since NADW flowing into the southwest Indian Ocean is largely blocked by the ridges (the Madagascar Ridge in the east and Davie Ridge in the north in the Mozambique Channel) and NIDW is the only source in the northern Indian Ocean that cannot provide a large amount of volume transport, CDW has to be a major source for the Indian deep circulation and ventilation in the north. Thus the question of NADW replacement becomes that of how the advective flows of CDW from the south are changed to be upwelled flows in the north—a water-mass transformation scenario. This study considered various processes causing motion across neutral surfaces. It is found that dianeutral mixing is vital to achieve CDW transformation. Basin-wide uniform dianeutral upwelling is detected in the entire Indian deep water north of 32°S, somewhat concentrated in the eastern Indian Ocean on the lowest surface. However, the integrated dianeutral transport is quite low, about a net of 0.2 Sv (1 Sv=10 6 m 3 s -1) across the lowermost neutral surface upward and 0.4 Sv across the uppermost surface upward north of 32°S with an error band of about 10-20% when an uncertainty of half-order change in diffusivities is assumed. Given about 10-15% of rough ridge area where dianeutral diffusivity could be about one order of magnitude higher (10 -4 m 2 s -1) due to internal-wave breaking, the additional amount of increased net dianeutral transport across the lowest neutral surface is still within that error band. The averaged net upward transport in the north

  2. Measurement of the neutrino mass splitting and flavor mixing by MINOS

    CERN Document Server

    Adamson, P; Armstrong, R; Auty, D J; Ayres, D S; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Boehnlein, D J; Bogert, D; Cavanaugh, S; Cherdack, D; Childress, S; Choudhary, B C; Coelho, J A B; Coleman, S J; Corwin, L; Cronin-Hennessy, D; Danko, I Z; de Jong, J K; Devenish, N E; Diwan, M V; Dorman, M; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grant, N; Grzelak, K; Habig, A; Harris, D; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Huang, X; Hylen, J; Ilic, J; Irwin, G M; Isvan, Z; Jaffe, D E; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kopp, S; Kordosky, M; Kreymer, A; Lang, K; Lefeuvre, G; Ling, J; Litchfield, P J; Litchfield, R P; Loiacono, L; Lucas, P; Mann, W A; Marshak, M L; Mayer, N; McGowan, A M; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Mitchell, J; Moore, C D; Morfín, J; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Oliver, W P; Orchanian, M; Ospanov, R; Paley, J; Patterson, R B; Pawloski, G; Pearce, G F; Petyt, D A; Phan-Budd, S; Plunkett, R K; Qiu, X; Ratchford, J; Raufer, T M; Rebel, B; Rodrigues, P A; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreiner, P; Shanahan, P; Smith, C; Sousa, A; Stamoulis, P; Strait, M; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tinti, G; Toner, R; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Yang, T; Zwaska, R

    2011-01-01

    Measurements of neutrino oscillations using the disappearance of muon neutrinos from the Fermilab NuMI neutrino beam as observed by the two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample from an exposure of $7.25 \\times 10^{20}$ protons on target. A fit to neutrino oscillations yields values of $|\\Delta m^2| = (2.32^{+0.12}_{-0.08})\\times10^{-3}$\\,eV$^2$ for the atmospheric mass splitting and $\\rm \\sin^2\\!(2\\theta) > 0.90$ (90%\\,C.L.) for the mixing angle. Pure neutrino decay and quantum decoherence hypotheses are excluded at 7 and 9 standard deviations, respectively.

  3. Measurement of the neutrino mass splitting and flavor mixing by MINOS.

    Science.gov (United States)

    Adamson, P; Andreopoulos, C; Armstrong, R; Auty, D J; Ayres, D S; Backhouse, C; Barr, G; Bishai, M; Blake, A; Bock, G J; Boehnlein, D J; Bogert, D; Cavanaugh, S; Cherdack, D; Childress, S; Choudhary, B C; Coelho, J A B; Coleman, S J; Corwin, L; Cronin-Hennessy, D; Danko, I Z; de Jong, J K; Devenish, N E; Diwan, M V; Dorman, M; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grant, N; Grzelak, K; Habig, A; Harris, D; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Huang, X; Hylen, J; Ilic, J; Irwin, G M; Isvan, Z; Jaffe, D E; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kopp, S; Kordosky, M; Kreymer, A; Lang, K; Lefeuvre, G; Ling, J; Litchfield, P J; Litchfield, R P; Loiacono, L; Lucas, P; Mann, W A; Marshak, M L; Mayer, N; McGowan, A M; Mehdiyev, R; Meier, J R; Messier, M D; Michael, D G; Miller, W H; Mishra, S R; Mitchell, J; Moore, C D; Morfín, J; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Oliver, W P; Orchanian, M; Ospanov, R; Paley, J; Patterson, R B; Pawloski, G; Pearce, G F; Petyt, D A; Phan-Budd, S; Plunkett, R K; Qiu, X; Ratchford, J; Raufer, T M; Rebel, B; Rodrigues, P A; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreiner, P; Shanahan, P; Smith, C; Sousa, A; Stamoulis, P; Strait, M; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tinti, G; Toner, R; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Yang, T; Zwaska, R

    2011-05-01

    Measurements of neutrino oscillations using the disappearance of muon neutrinos from the Fermilab NuMI neutrino beam as observed by the two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample from an exposure of 7.25×10(20) protons on target. A fit to neutrino oscillations yields values of |Δm(2)|=(2.32(-0.08)(+0.12))×10(-3) eV(2) for the atmospheric mass splitting and sin(2)(2θ)>0.90 (90% C.L.) for the mixing angle. Pure neutrino decay and quantum decoherence hypotheses are excluded at 7 and 9 standard deviations, respectively.

  4. Neutrino mixing matrix and masses from a generalized Friedberg-Lee model

    Science.gov (United States)

    Razzaghi, N.; Gousheh, S. S.

    2014-02-01

    The overall characteristics of the solar and atmospheric neutrino oscillation are approximately consistent with a tribimaximal form of the mixing matrix U of the lepton sector. Exact tribimaximal mixing leads to θ13=0. However, recent results from the Daya Bay and RENO experiments have established a nonzero value for θ13. Keeping the leading behavior of U as tribimaximal, we use a generalized Friedberg-Lee neutrino mass model along with a complementary ansatz to incorporate a nonzero θ13 along with CP violation. We generalize this model in two stages: In the first stage, we assume μ -τ symmetry and add imaginary components which leads to nonzero phases. In the second stage, we add a perturbation with real components which breaks the μ-τ symmetry, and this leads to a nonzero value for θ13. The combination of these two generalizations leads to CP violation. Using only two sets of the experimental data, we can fix all of the parameters of our model and predict not only values for the other experimental data, which agree well with the available data, but also the masses of neutrinos and the CP-violating phases and parameters. These predictions include the following: ⟨mνe⟩≈(0.033-0.037) eV, ⟨mνμ⟩≈(0.043-0.048) eV, ⟨mντ⟩≈(0.046-0.051) eV, and 59.21°≲δ ≲59.34°.

  5. Deviation from tri-bimaximal mixings through flavour twisters in inverted and normal hierarchical neutrino mass models

    Indian Academy of Sciences (India)

    N Nimai Singh; Monisa Rajkhowa; Abhijit Borah

    2007-10-01

    We explore a novel possibility for lowering the solar mixing angle (12) from tri-bimaximal mixings, without sacrificing the predictions of maximal atmospheric mixing angle (23 = 45°) and zero reactor angle (13 = 0°) in the inverted and normal hierarchical neutrino mass models having 2-3 symmetry. This can be done through the identification of a flavour twister term in the texture of neutrino mass matrix and the variation of such term leads to lowering of solar mixing angle. For the observed ranges of $ m_{21}^{2}$ and $ m_{23}^{2}$, we calculate the predictions on tan2 12 = 0.5, 0.45, 0.35 for different input values of the parameters in the neutrino mass matrix. We also observe a possible transition from inverted hierarchical model having even CP parity (Type-IHA) to inverted hierarchical model having odd CP parity (Type-IHB) in the first two mass eigenvalues, when there is a change in input values of parameters in the same mass matrix. The present work differs from the conventional approaches for the deviations from tri-bimaximal mixing, where the 2-3 symmetry is broken, leading to 23 ≠ 45° and 13 ≠ 0°.

  6. Acoustic metamaterial with negative mass density in water

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Huaijun; Zhai, Shilong; Ding, Changlin; Luo, Chunrong; Zhao, Xiaopeng, E-mail: xpzhao@nwpu.edu.cn [Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710129 (China)

    2015-09-07

    A two-dimensional (2D) acoustic metamaterial (AM) with negative effective mass density in water is designed by periodically arranging hollow tube “meta-atoms.” Experimental and simulated results demonstrate that transmission dips accompanied with inverse phases are presented in the transmission spectra of the 2D AM at the ultrasonic frequency band. Effective parameters extracted from the experimental measured transmission and reflection coefficients of the 2D AM show that the effective mass density and refractive index are negative near the dip frequency range of 35.31–35.94 kHz. The simulation also shows the negative response in the 2D AM. Due to the excellent properties, the 2D AM is appealing for the potential applications in areas such as subwavelength imaging, ultrasonic cloaking in water, and so on.

  7. Stable Isotope Analysis of Water Indicates that Mixing Occurs between Mobile and Tightly-Bound Soil Water

    Science.gov (United States)

    Vargas, A. I.; Schaffer, B.; Yuhong, L.; Sternberg, L. O.

    2016-12-01

    Stable oxygen (δ18O) and hydrogen (δ2H) isotope composition of precipitation, soil and plants have been studied over the years to understand the mechanism of soil water movement and the depth of plant water uptake in the soil water profile. Recent studies have suggested that in soil during the wet season, tightly bound water does not mix with mobile water but is retained in the soil until the dry season when it is taken up by plants via the force of transpiration. To test this, we sampled δ18O and δ2H in plant stems as a proxy for wet season mobile water and dry season bound water in two types of soils to determine if mixing occurs between mobile and tightly bound soil water. Plastic pots were filled with clay or very gravelly loam soil and a Persea americana tree was planted in each pot. Soil in each pot was first saturated with tap water to fully label the bound water with the isotopic identity of tap water and then fully saturated with either tap water (T) or isotopically-enriched pool water (P) and covered with white polyethylene to prevent evaporation. After saturating the soil, δ18O and δ2H of water draining from each pot were similar to those of water added to each pot for both the T and P treatments. For each treatment, δ18O and δ2H in plant stems were sampled 2-3 days after soil was initially saturated (simulated wet season; soil tension 80.0 kPa). During the "dry season", there was a significant difference between T and P treatments for δ18O and δ2H in plant stems, indicating that bound water accessed by plants in the P treatment did not retain the tap water label and mixing occurred between mobile and bound water in the soil. Comparing P-T in the wet season with P-T in the dry season indicated that as much as 95% of water freely exchanged between the mobile and bound components of the soil. This is contrary to recent studies suggesting that no mixing occurs.

  8. Circulation and mixing of Mediterranean water west of the Iberian Peninsula

    Science.gov (United States)

    Daniault, N.; Mazé, J. P.; Arhan, M.

    1994-11-01

    The spreading of water of Mediterranean origin west of the Iberian Peninsula was studied with hydrographic data from several recent cruises and current measurements from the BORD-EST programme. The vertical breakdown of the "Mediterranean salt" content reveals the dominant contribution of the so-called lower core of the outflow (60%), and the significant fraction (22%) brought downward to levels below 1500 m by diffusion. Intense salinity maxima in the upper core (18%) are only encountered south of 38°N in the vein flowing northward along the continental slope, and at a few stations in the deep ocean. Apart from the coastally trapped vein, other preferred paths of the water mass are revealed by the horizontal distributions of salinity maximum and Mediterranean Water percentage. One is southward, west of the Gorringe Bank, and two northwestward ones lie around 40°N and west of the Galicia Bank. Year-long velocity measurements in the Tagus Basin show westward mean values of 7 × 10 -2 m s -1 at 1000 m associated with a very intense mesoscale variability. This variability is related to the pronounced dynamical signature of the outflow which favours instability in any branch having detached from the slope current. From a mixing point of view, the strong interleaving activity occurring near Cape St-Vincent is illustrated, but its contribution to the downstream salinity decrease in the coastally trapped vein is weak. Current and meddy detachment play the dominant role, with a scaling estimate of their associated lateral diffusivity of order 500 m 2 s -1. The statistical distribution of the density ratio parameter, which governs double-diffusion at the base of the Mediterranean Water, was found to be very tight around Rπ = 1.3 in the temperature range of 5°C< φ < 8°C. North of 40°N, the presence of a fraction of Labrador Sea Water in the underlying water is shown to decrease that parameter and should favour the formation of salt fingers.

  9. A Model of Fermion Masses and Flavor Mixings with Family Symmetry SU(3) U(1)

    Institute of Scientific and Technical Information of China (English)

    杨为民; 王琦; 钟金金

    2012-01-01

    The family symmetry SU(3) U(1) is proposed to solve flavor problems about fermion masses and flavor mixings. It is breaking is implemented by some flavon fields at the high-energy scale. In addition a discrete group Z2 is introduced to generate tiny neutrino masses, which is broken by a real singlet scalar field at the middle-energy scale. The low-energy effective theory is elegantly obtained after all of super-heavy fermions are integrated out and decoupling. All the fermion mass matrices are regularly characterized by four fundamental matrices and thirteen parameters. The model can perfectly fit and account for all the current experimental data about the fermion masses and flavor mixings, in particular, it finely predicts the first generation quark masses and the values of θ13and JCp in neutrino physics. All of the results are promising to be tested in the future experiments.

  10. Integrated impacts of future electricity mix scenarios on select southeastern US water resources

    Science.gov (United States)

    Yates, D.; Meldrum, J.; Flores-Lopez, F.; Davis, Michelle

    2013-09-01

    Recent studies on the relationship between thermoelectric cooling and water resources have been made at coarse geographic resolution and do not adequately evaluate the localized water impacts on specific rivers and water bodies. We present the application of an integrated electricity generation-water resources planning model of the Apalachicola/Chattahoochee/Flint (ACF) and Alabama-Coosa-Tallapoosa (ACT) rivers based on the regional energy deployment system (ReEDS) and the water evaluation and planning (WEAP) system. A future scenario that includes a growing population and warmer, drier regional climate shows that benefits from a low-carbon, electricity fuel-mix could help maintain river temperatures below once-through coal-plants. These impacts are shown to be localized, as the cumulative impacts of different electric fuel-mix scenarios are muted in this relatively water-rich region, even in a warmer and drier future climate.

  11. Gelatin increases the coarseness of whey protein gels and impairs water exudation from the mixed gel at low temperatures

    NARCIS (Netherlands)

    Martin, A.H.; Bakhuizen, E.; Ersch, C.; Urbonaite, V.; Jongh, H.H.J. de; Pouvreau, L.

    2016-01-01

    To understand the origin of water holding of mixed protein gels, a study was performed on water exudation from mixed whey protein (WP)-gelatin gels upon applied pressure. Mixed gels were prepared with varying WP and gelatin concentration and gelatin type to obtain gels with a wide range of gel

  12. S{sub 3} discrete group as a source of the quark mass and mixing pattern in 331 models

    Energy Technology Data Exchange (ETDEWEB)

    Carcamo Hernandez, A.E. [Universidad Tecnica Federico Santa Maria and Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile); Martinez, R.; Nisperuza, Jorge [Universidad Nacional de Colombia, Ciudad Universitaria, Departamento de Fisica, Bogota D.C. (Colombia)

    2015-02-01

    We propose a model based on the SU(3){sub C} x SU(3){sub L} x U(1){sub X} gauge symmetry with an extra S{sub 3} x Z{sub 2} x Z{sub 4} x Z{sub 12} discrete group, which successfully accounts for the SM quark mass and mixing pattern. The observed hierarchy of the SM quark masses and quark mixing matrix elements arises from the Z{sub 4} and Z{sub 12} symmetries, which are broken at a very high scale by the SU(3){sub L} scalar singlets (σ,ζ) and τ, charged under these symmetries, respectively. The Cabbibo mixing arises from the down-type quark sector whereas the up quark sector generates the remaining quark mixing angles. The obtained magnitudes of the CKM matrix elements, the CP violating phase, and the Jarlskog invariant are in agreement with the experimental data. (orig.)

  13. Can four-zero-texture mass matrix model reproduce the quark and lepton mixing angles and CP violating phases?

    CERN Document Server

    Matsuda, K; Matsuda, Koichi; Nishiura, Hiroyuki

    2006-01-01

    We reconsider an universal mass matrix model which has a seesaw-invariant structure with four-zero texture common to all quarks and leptons. The CKM quark and MNS lepton mixing matrices of the model are analyzed analytically.We show that the model can be consistent with all the experimental data of neutrino oscillation and quark mixings by tuning free parameters of the model. It is also shown that the model predicts a relatively large value for (1,3) element of the MNS lepton mixing matrix, |(U_{MNS})_{13}|^2 \\simeq 2.6 \\times 10^{-2}. Using the seesaw mechanism, we also discuss the conditions for the components of the Dirac and the right-handed Majorana neutrino mass matrices which lead to the neutrino mass matrix consistent with the experimental data.

  14. Lepton mass and mixing in a simple extension of the Standard Model based on T7 flavor symmetry

    CERN Document Server

    Vien, V V

    2016-01-01

    A simple Standard Model Extension based on $T_7$ flavor symmetry which accommodates lepton mass and mixing with non-zero $\\theta_{13}$ and CP violation phase is proposed. At the tree- level, the realistic lepton mass and mixing pattern is derived through the spontaneous symmetry breaking by just one vacuum expectation value ($v$) which is the same as in the Standard Model. Neutrinos get small masses from one $SU(2)_L$ doublet and two $SU(2)_L$ singlets in which one being in $\\underline{1}$ and the two others in $\\underline{3}$ and $\\underline{3}^*$ under $T_7$ , respectively. The model also gives a remarkable prediction of Dirac CP violation $\\delta_{CP}=172.598^\\circ$ in both normal and inverted hierarchies which is still missing in the neutrino mixing matrix.

  15. Biofuels spills in surface waters - a laboratory investigation of mixing and interfacial dynamics

    Science.gov (United States)

    Wang, Xiaoxiang; Cotel, Aline

    2016-11-01

    There are increasing risks of spills of ethanol-based biofuels in aquatic environments, however the environmental impact of such accidents is poorly understood and no adequate mitigation strategies are in place today. The interaction of water and biofuels is a complex dynamical problem and we aim to quantify the physical processes involved in such dynamics. A solution of ethanol and glycol is used to represent a typical ethanol-based fuel. A small-scale Plexiglas tank has been designed to investigate the effect of natural conditions on the mixing of water and biofuels, e.g. slope angle, flow rate, wave amplitude and frequency in wind driven conditions. Our previous work showed that the existence of two distinct mixing regimes; a first turbulence-driven fast mixing regime and a second regime driven by interface instabilities. We investigate these mixing regimes under an extended range of physical parameters representing more natural configurations. Funded by NSF.

  16. Using the Mass-Independent Signature of Atmospheric O2 as a Tracer for Biological Productivity and for Ocean Mixing

    Science.gov (United States)

    Hendricks, M. B.; Bender, M.; Barnett, B.

    2002-12-01

    We have measured O2:Ar ratios and the O2 triple isotope composition (16O/17O/18O) along six meridional lines in the equatorial Pacific (8°N to 8°S at 95°W, 110°W, 125°W, 140°W, 155°W and 170°W). The results constrain biological productivity in the mixed layer and demonstrate the utility of O2 and its isotopes as tracers of biology and of mixing in the underlying water column. Stratospheric processing of O3 creates a mass independent fractionation in atmospheric O2 and lowers Ln17Δ of O2 in air. Ln17Δ is defined as ln(δ17O/1000+1) - 0.518xln(δ18O/1000+1), and is approximately equal to δ17O - 0.518xδ18O. Ln17Δ of dissolved O2 is thus a measure of the fraction of dissolved O2 derived from dissolution of atmospheric O2 (Ln17Δ = 0.015‰ ) rather than photosynthesis (Ln17Δ = 0.249‰ ). Respiration consumes 16O preferentially and fractionates dissolved O2 in a mass dependent manner, leaving Ln17Δ unchanged and increasing δ18O of O2. We examine the expected behavior of O2 in four simple closed systems and show δ18O and Ln17Δ of dissolved O2 covary with O2:Ar ratios in a way that conforms to these cases. 1) In the steady-state mixed layer, O2:Ar ratios are close to saturation, δ18O of O2 is low and Ln17Δ is variable, as photosynthesis, respiration and gas exchange all contribute to the O2 pool. 2) Deeper aphotic zone waters that have never entered the euphotic zone have low O2:Ar ratios, high δ18O, and low Ln17Δ, reflecting respiration in the absence of photosynthesis. 3) Waters of the sunlit thermocline, which are net-heterotrophic, also have low O2:Ar ratios and high δ18O, but elevated Ln17Δ, as respiration and photosynthesis proceed in the absence of gas exchange. 4) Equatorial undercurrent waters that recently upwelled into the euphotic zone have low O2:Ar ratios, reduced δ18O values (recent addition of photosynthetic O2 cancels the earlier respiratory enrichment), and elevated Ln17Δ from photosynthesis. By adding oxygen isotopes to the

  17. Tracers confirm downward mixing of Tyrrhenian Sea upper waters associated with the Eastern Mediterranean Transient

    Directory of Open Access Journals (Sweden)

    W. Roether

    2011-01-01

    Full Text Available Observations of tritium and 3He in the Tyrrhenian Sea, 1987–2009, confirm the enhanced vertical mixing of intermediate waters into the deep waters that has been noted and associated with the Eastern Mediterranean Transient in previous studies. Our evidence for the mixing rests on increasing tracer concentrations in the Tyrrhenian deep waters, accompanied by decreases in the upper waters, which are supplied from the Eastern Mediterranean. The downward transfer is particularly evident between 1987 and 1997. Later on, information partly rests on increasing tritium-3He ages; here we correct the observed 3He for contributions released from the ocean floor. The Tyrrhenian tracer distributions are fully compatible with data upstream of the Sicily Strait and in the Western Mediterranean. The tracer data show that mixing reached to the bottom and confirm a cyclonic nature of the deep water circulation in the Tyrrhenian. They furthermore indicate that horizontal homogenization of the deep waters occurs on a time scale of roughly 5 years. Various features point to a reduced impact of Western Mediterranean Deep Water (WMDW in the Tyrrhenian during the enhanced-mixing period. This is an important finding because it implies less upward mixing of WMDW, which has been named a major process to enable the WMDW to leave the Mediterranean via the Gibraltar Strait. On the other hand, the TDW outflow for several years represented a major influx of enhanced salinity and density waters into the deep-water range of the Western Mediterranean.

  18. Outdoor mass culture of Spirulina maxima in sea-water

    Energy Technology Data Exchange (ETDEWEB)

    Tredici, M.R.; Papuzzo, T.; Tomaselli, L.

    1986-04-01

    The results of a whole year experiment on the outdoor mass culture of Spirulina maxima strain 4Mx on fertilized sea-water are reported. Carbonate and phosphate precipitation in the seawater media was prevented by maintaining a low concentration of phosphate and by controlling the pH in the range of 8.0-8.3. The mean annual yield of biomass on sea-water plus urea as nitrogen source was 7.35 g(dry weight)m/sup -2/.day/sup -1/, a value slightly lower than that obtained on the standard bicarbonate medium (8.14 g.m/sup -2/.day/sup -1/). On sea-water plus nitrate the yield was only 5.2 g.m/sup -2/.day/sup -1/. The nitrogen content of the biomass was higher in summer and lower in winter. The seasonal effect was more evident when nitrate was the nitrogen source.

  19. Numerical study on the impact of the 18.6-year period nodal tidal cycle on water masses in the subarctic North Pacific

    Science.gov (United States)

    Osafune, S.; Yasuda, I.

    2012-05-01

    A series of numerical experiments is performed to test the hypothesis that temporal variations in localized strong tidal mixing related to the 18.6-year period nodal tidal cycle induce water mass variations. It is suggested that enhanced mixing around the Bering Sea, as that around the Okhotsk Sea, have an impact on water masses broadly in the North Pacific including the Bering Sea and the Okhotsk Sea. Oscillatory tidal mixing with a 18.6-year period reproduces water mass variations in salinity and isopycnal potential temperature around the subarctic North Pacific that are qualitatively consistent with observed variations. When the amplitude of oscillatory vertical diffusivity is 15% of the long-term mean (and even when the amplitude is as small as 3 cm2/s, as obtained for a long-term mean of 20 cm2/s), the amplitude of the salinity variation near regions of strong mixing is smaller than but on the same order of magnitude as that observed. The induced salinity anomaly spreads broadly, over a distance of several hundreds of kilometers, by mean currents with a short lag time of less than 3 years, and is suggested to influence the model winter mixed layer over broad regions. These results support the hypothesis stated above and suggest that it is necessary to clarify spatial and temporal variations in tidal mixing to reproduce both the mean states of and temporal variations in water masses of the subarctic North Pacific.

  20. Water model experiments of multiphase mixing in the top-blown smelting process of copper concentrate

    Institute of Scientific and Technical Information of China (English)

    Hong-liang Zhao; Pan Yin; Li-feng Zhang; and Sen Wang

    2016-01-01

    We constructed a 1:10 cold water experimental model by geometrically scaling down an Isa smelting furnace. The mixing proc-esses at different liquid heights, lance diameters, lance submersion depths, and gas flow rates were subsequently measured using the conduc-tivity method. A new criterion was proposed to determine the mixing time. On this basis, the quasi-equations of the mixing time as a function of different parameters were established. The parameters of the top-blown smelting process were optimized using high-speed photography. An excessively high gas flow rate or excessively low liquid height would enhance the fluctuation and splashing of liquid in the bath, which is unfavorable for material mixing. Simultaneously increasing the lance diameter and the lance submersion depth would promote the mixing in the bath, thereby improving the smelting efficiency.

  1. Water model experiments of multiphase mixing in the top-blown smelting process of copper concentrate

    Science.gov (United States)

    Zhao, Hong-liang; Yin, Pan; Zhang, Li-feng; Wang, Sen

    2016-12-01

    We constructed a 1:10 cold water experimental model by geometrically scaling down an Isa smelting furnace. The mixing processes at different liquid heights, lance diameters, lance submersion depths, and gas flow rates were subsequently measured using the conductivity method. A new criterion was proposed to determine the mixing time. On this basis, the quasi-equations of the mixing time as a function of different parameters were established. The parameters of the top-blown smelting process were optimized using high-speed photography. An excessively high gas flow rate or excessively low liquid height would enhance the fluctuation and splashing of liquid in the bath, which is unfavorable for material mixing. Simultaneously increasing the lance diameter and the lance submersion depth would promote the mixing in the bath, thereby improving the smelting efficiency.

  2. Insights on Clusters Formation Mechanism by Time of Flight Mass Spectrometry. 2. The Case of Acetone-Water Clusters

    Science.gov (United States)

    Apicella, B.; Li, X.; Passaro, M.; Russo, C.

    2016-11-01

    This paper is the second of a series dealing with clusters formation mechanism. In part 1, water clusters with the addition of an electrophilic molecule such as ethanol were studied by Time Of Flight Mass Spectrometry (TOFMS). Mass distributions of molecular clusters of ethanol, water and ethanol-water mixed clusters, were obtained by means of two different ionization methods: Electron Ionization (EI) and picosecond laser Photo-Ionization (PI) at a wavelength of 355 nm. In part 2, the same experimental approach was employed to obtain mass spectra of clusters generated by acetone-water binary mixtures with a different composition. Strong dependence of the mass spectra of clusters with EI and PI on the acetone-water mixing ratio was observed. It was shown that the spectral pattern changes gradually and water-rich cluster signals become fainter while acetone-rich cluster signals become more intensive with increasing acetone concentrations from 0.3% to 40%. Owing to the hydrogen bond acceptor character of acetone, its self-association is discouraged with respect to ethanol. The autocorrelation function (AF) was used to analyze the variation of the water clusters composition with the increase of the acetone concentration in terms of fundamental periodicities. However, although acetone and ethanol present a very different hydrogen-bonding ability, similarly to ethanol-water system, in acetone-water system the formation of water-rich clusters and subsequent metastable fragmentation are the dominant process that determine the clusters distribution, irrespective of the ionization process, while the ionization process significantly affects the acetone-rich clusters distribution.

  3. Selecting water-alcohol mixed solvent for synthesis of polydopamine nano-spheres using solubility parameter

    OpenAIRE

    Jiang, Xiaoli; Wang, Yinling; Li, Maoguo

    2014-01-01

    The solvent plays an important role in a given chemical reaction. Since most reaction in nature occur in the mixed-solvent systems, a comprehensive principle for solvent optimization was required. By calculating the Hansen solubility parameters (HSP) distance Ra , we designed a model experiment to explore the influence of mixed solvents on the chemical synthesis. The synthesis of polydopamine (PDA) in the water-alcohol system was chosen as model. As predicted, the well-dispersed PDA spheres w...

  4. Mixed convective heat and mass transfer analysis for peristaltic transport in an asymmetric channel with Soret and Dufour effects

    Institute of Scientific and Technical Information of China (English)

    F M Abbasi; A Alsaedi; T Hayat

    2014-01-01

    The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number.

  5. The Gell-Mann - Okubo Mass Relation among Baryons from Fully-Dynamical, Mixed-Action Lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Konstantinos Orginos; Silas Beane; Martin Savage

    2007-10-01

    We explore the Gell-Mann - Okubo mass relation among the octet baryons using fully-dynamical, mixed-action (domain-wall on rooted-staggered) lattice QCD calculations at a lattice spacing of b {approx} 0.125 fm and pion masses of m{sub pi} {approx} 290 MeV, 350 MeV, 490 MeV and 590 MeV. Deviations from the Gell-Mann - Okubo mass relation are found to be small at each quark mass.

  6. Water solubility enhancements of pyrene by single and mixed surfactant solutions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water solubility enhancements of pyrene by both single-surfactant and mixed-surfactant solutions were compared andevaluated. The solubility of pyrene in water was greatly enhanced by each of Triton X-100 (TX100), Triton X-405 (TX405), Brij 35 and SDS, in which the water solubility enhancements increased with increasing surfactant concentrations. The extent of solubility enhancements at surfactant concentrations below the CMC is the order of TX100 > Brij 35 > TX405 > SDS; the sequence at surfactantconcentrations above the CMC is TX100 > Brij 35 > SDS > TX405. Pyrene was solubilized synergistically by anionic-nonionic mixed surfactant solutions, especially at low surfactant concentrations. The synergistic power of the mixed surfactants is SDS-TX405 > SDS-Brij 35 > SDS-TX100. The synergism as noted is attributed to increasing Kmc and/or decreasing the CMC of the mixed surfactan solution. For SDS-TX405 and SDS-Brij 35 mixed surfactant solutions, an increase in Kmc is coupled with a decrease in the CMC; for SDS-TX100, only a decreased in the CMC value is noted. Mixed-surfactant solutions may improve the performance of the surfactant-enhanced remediation (SER) of soils by increasing the bioavailability and biodegradation of non-aqueous-phase organic pollutants and reducing the level of surfactant pollution and remediation expenses.

  7. Fluid Flow and Mixing in Non-Isothermal Water Model of Continuous Casting Tundish

    Institute of Scientific and Technical Information of China (English)

    Mehdi ALIZADEH; Hossein EDRIS; Ali SHAFYEI

    2008-01-01

    Fluid flow and mixing of molten steel in a twin-slab-strand continuous casting tundish were investigated using a mixing model under non-isothermal conditions. This model led to a set of ordinary differential equations that were solved with a Runge-Kutta algorithm. Steady state water modeling was carried out under non-isothermal conditions. Experimental data obtained from the water model were used to calibrate the mixing model. Owing to the presence of a mixed convection in the non-isothermal conditions, a channelizing flow would be created in the fluid inside the tundish. A mixing model was designed that was capable of predicting RTD (residence time distribution) curves for different cases in non-isothermal conditions. The relationship between RTD parameters and the Tu (tundish Richardson number) was obtained for various cases under non-isothermal conditions. The results show that the RTD parameters were completely different under isothermal and non-isothermal conditions. The comparison of the RTD curves between the isothermal and non-isothermal conditions presents that the extent of mixing in the tundish in nonisothermal conditions is lower than the mixing extent in isothermal conditions.

  8. Study on Mixed Solvency Concept in Formulation Development of Aqueous Injection of Poorly Water Soluble Drug

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Solanki

    2013-01-01

    Full Text Available In the present investigation, mixed-solvency approach has been applied for the enhancement of aqueous solubility of a poorly water- soluble drug, zaltoprofen (selected as a model drug, by making blends (keeping total concentrations 40% w/v, constant of selected water-soluble substances from among the hydrotropes (urea, sodium benzoate, sodium citrate, nicotinamide; water-soluble solids (PEG-4000, PEG-6000; and co-solvents (propylene glycol, glycerine, PEG-200, PEG-400, PEG-600. Aqueous solubility of drug in case of selected blends (12 blends ranged from 9.091 ± 0.011 mg/ml–43.055 ± 0.14 mg/ml (as compared to the solubility in distilled water 0.072 ± 0.012 mg/ml. The enhancement in the solubility of drug in a mixed solvent containing 10% sodium citrate, 5% sodium benzoate and 25 % S cosolvent (25% S cosolvent contains PEG200, PEG 400, PEG600, Glycerine and Propylene glycol was more than 600 fold. This proved a synergistic enhancement in solubility of a poorly water-soluble drug due to mixed cosolvent effect. Each solubilized product was characterized by ultraviolet and infrared techniques. Various properties of solution such as pH, viscosity, specific gravity and surface tension were studied. The developed formulation was studied for physical and chemical stability. This mixed solvency shall prove definitely a boon for pharmaceutical industries for the development of dosage form of poorly water soluble drugs.

  9. Assessment of condensation of water vapor in the mixing chamber by CFD method

    Directory of Open Access Journals (Sweden)

    Vojkůvková Petra

    2015-01-01

    Full Text Available The analyzed topic belongs to the field of design and operation of HVAC systems, focusing mainly on mixing chambers. The paper deals with problems of condensation and freezing of water vapour on walls of mixing chambers in a special case, when the partial pressure of the final resulting state of the mixture of warm moist air and colder air is located above the saturation limit. Experimental in situ methods and computer computational fluid dynamics (CFD modelling method were used for processing. The main contribution of this work is the finding that partial condensation and freezing of water vapour may occur in local parts of the mixing chamber. It causes problems in terms of hygienic safety and service life of these devices. In particular it has been found that condensation and freezing of water vapour may occur even if relative humidity of the resulting mixture is about 70 %.

  10. Extraction of Lithium from Lepidolite Using Mixed Grinding with Sodium Sulfide Followed by Water Leaching

    Directory of Open Access Journals (Sweden)

    Jaeryeong Lee

    2015-11-01

    Full Text Available Mixed grinding with Na2S followed by water leaching was performed to extract Li from lepidolite. The leachability of Li increases dramatically in the ground mixture, regardless of the mixing ratio over the range of 1:1 to 3:1, while only 4.53% of Li was extracted in lepidolite ground without Na2S. The leachability increased with an increase of the grinding time, and ultimately, 93% of the Li was leached by water from the ground mixture with a weight ratio of 3:1 (Na2S:Lepidolite. In the process of the mixed grinding, the Li-contained lepidolite was destructured crystallographically, and it might have changed to different compounds. This process enables us to extract Li from lepidolite via a water leaching treatment.

  11. Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum

    CERN Document Server

    Aab, A; Aglietta, M; Ahn, E J; Samarai, I Al; Albuquerque, I F M; Allekotte, I; Allison, P; Almela, A; Castillo, J Alvarez; Alvarez-Muñiz, J; Ambrosio, M; Anastasi, G A; Anchordoqui, L; Andrada, B; Andringa, S; Aramo, C; Arqueros, F; Arsene, N; Asorey, H; Assis, P; Aublin, J; Avila, G; Badescu, A M; Balaceanu, A; Baus, C; Beatty, J J; Becker, K H; Bellido, J A; Berat, C; Bertaina, M E; Bertou, X; Biermann, P L; Billoir, P; Biteau, J; Blaess, S G; Blanco, A; Blazek, J; Bleve, C; Boháčová, M; Boncioli, D; Bonifazi, C; Borodai, N; Botti, A M; Brack, J; Brancus, I; Bretz, T; Bridgeman, A; Briechle, F L; Buchholz, P; Bueno, A; Buitink, S; Buscemi, M; Caballero-Mora, K S; Caccianiga, B; Caccianiga, L; Cancio, A; Canfora, F; Caramete, L; Caruso, R; Castellina, A; Cataldi, G; Cazon, L; Cester, R; Chavez, A G; Chiavassa, A; Chinellato, J A; Chudoba, J; Clay, R W; Colalillo, R; Coleman, A; Collica, L; Coluccia, M R; Conceição, R; Contreras, F; Cooper, M J; Coutu, S; Covault, C E; Cronin, J; Dallier, R; D'Amico, S; Daniel, B; Dasso, S; Daumiller, K; Dawson, B R; de Almeida, R M; de Jong, S J; De Mauro, G; Neto, J R T de Mello; De Mitri, I; de Oliveira, J; de Souza, V; Debatin, J; del Peral, L; Deligny, O; Di Giulio, C; Di Matteo, A; Castro, M L Díaz; Diogo, F; Dobrigkeit, C; D'Olivo, J C; Dorofeev, A; Anjos, R C dos; Dova, M T; Dundovic, A; Ebr, J; Engel, R; Erdmann, M; Erfani, M; Escobar, C O; Espadanal, J; Etchegoyen, A; Falcke, H; Fang, K; Farrar, G; Fauth, A C; Fazzini, N; Fick, B; Figueira, J M; Filevich, A; Filipčič, A; Fratu, O; Freire, M M; Fujii, T; Fuster, A; García, B; Garcia-Pinto, D; Gaté, F; Gemmeke, H; Gherghel-Lascu, A; Ghia, P L; Giaccari, U; Giammarchi, M; Giller, M; Głas, D; Glaser, C; Glass, H; Golup, G; Berisso, M Gómez; Vitale, P F Gómez; González, N; Gookin, B; Gordon, J; Gorgi, A; Gorham, P; Gouffon, P; Grillo, A F; Grubb, T D; Guarino, F; Guedes, G P; Hampel, M R; Hansen, P; Harari, D; Harrison, T A; Harton, J L; Hasankiadeh, Q; Haungs, A; Hebbeker, T; Heck, D; Heimann, P; Herve, A E; Hill, G C; Hojvat, C; Holt, E; Homola, P; Hörandel, J R; Horvath, P; Hrabovský, M; Huege, T; Hulsman, J; Insolia, A; Isar, P G; Jandt, I; Jansen, S; Johnsen, J A; Josebachuili, M; Kääpä, A; Kambeitz, O; Kampert, K H; Kasper, P; Katkov, I; Keilhauer, B; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Krause, R; Krohm, N; Kuempel, D; Mezek, G Kukec; Kunka, N; Awad, A Kuotb; LaHurd, D; Latronico, L; Lauscher, M; Lautridou, P; Lebrun, P; Legumina, R; de Oliveira, M A Leigui; Letessier-Selvon, A; Lhenry-Yvon, I; Link, K; Lopes, L; López, R; Casado, A López; Luce, Q; Lucero, A; Malacari, M; Mallamaci, M; Mandat, D; Mantsch, P; Mariazzi, A G; Mariş, I C; Marsella, G; Martello, D; Martinez, H; Bravo, O Martínez; Meza, J J Masías; Mathes, H J; Mathys, S; Matthews, J; Matthews, J A J; Matthiae, G; Mayotte, E; Mazur, P O; Medina, C; Medina-Tanco, G; Melo, D; Menshikov, A; Messina, S; Micheletti, M I; Middendorf, L; Minaya, I A; Miramonti, L; Mitrica, B; Mockler, D; Molina-Bueno, L; Mollerach, S; Montanet, F; Morello, C; Mostafá, M; Müller, G; Muller, M A; Müller, S; Naranjo, I; Navas, S; Nellen, L; Neuser, J; Nguyen, P H; Niculescu-Oglinzanu, M; Niechciol, M; Niemietz, L; Niggemann, T; Nitz, D; Nosek, D; Novotny, V; Nožka, H; Núñez, L A; Ochilo, L; Oikonomou, F; Olinto, A; Selmi-Dei, D Pakk; Palatka, M; Pallotta, J; Papenbreer, P; Parente, G; Parra, A; Paul, T; Pech, M; Pedreira, F; Pękala, J; Pelayo, R; Peña-Rodriguez, J; Pereira, L A S; Perrone, L; Peters, C; Petrera, S; Phuntsok, J; Piegaia, R; Pierog, T; Pieroni, P; Pimenta, M; Pirronello, V; Platino, M; Plum, M; Porowski, C; Prado, R R; Privitera, P; Prouza, M; Quel, E J; Querchfeld, S; Quinn, S; Ramos-Pollant, R; Rautenberg, J; Ravel, O; Ravignani, D; Reinert, D; Revenu, B; Ridky, J; Risse, M; Ristori, P; Rizi, V; de Carvalho, W Rodrigues; Fernandez, G Rodriguez; Rojo, J Rodriguez; Rodríguez-Frías, M D; Rogozin, D; Rosado, J; Roth, M; Roulet, E; Rovero, A C; Saffi, S J; Saftoiu, A; Salazar, H; Saleh, A; Greus, F Salesa; Salina, G; Gomez, J D Sanabria; Sánchez, F; Sanchez-Lucas, P; Santos, E M; Santos, E; Sarazin, F; Sarkar, B; Sarmento, R; Sarmiento-Cano, C; Sato, R; Scarso, C; Schauer, M; Scherini, V; Schieler, H; Schmidt, D; Scholten, O; Schovánek, P; Schröder, F G; Schulz, A; Schulz, J; Schumacher, J; Sciutto, S J; Segreto, A; Settimo, M; Shadkam, A; Shellard, R C; Sigl, G; Silli, G; Sima, O; Śmiałkowski, A; Šmída, R; Snow, G R; Sommers, P; Sonntag, S; Sorokin, J; Squartini, R; Stanca, D; Stanič, S; Stasielak, J; Strafella, F; Suarez, F; Durán, M Suarez; Sudholz, T; Suomijärvi, T; Supanitsky, A D; Sutherland, M S; Swain, J; Szadkowski, Z; Taborda, O A; Tapia, A; Tepe, A; Theodoro, V M; Timmermans, C; Peixoto, C J Todero; Tomankova, L; Tomé, B; Tonachini, A; Elipe, G Torralba; Machado, D Torres; Torri, M; Travnicek, P; Trini, M; Ulrich, R; Unger, M; Urban, M; Valbuena-Delgado, A; Galicia, J F Valdés; Valiño, I; Valore, L; van Aar, G; van Bodegom, P; Berg, A M van den; van Vliet, A; Varela, E; Cárdenas, B Vargas; Varner, G; Vázquez, J R; Vázquez, R A; Veberič, D; Verzi, V; Vicha, J; Villaseñor, L; Vorobiov, S; Wahlberg, H; Wainberg, O; Walz, D; Watson, A A; Weber, M; Weindl, A; Wiencke, L; Wilczyński, H; Winchen, T; Wittkowski, D; Wundheiler, B; Wykes, S; Yang, L; Yelos, D; Younk, P; Yushkov, A; Zas, E; Zavrtanik, D; Zavrtanik, M; Zepeda, A; Zimmermann, B; Ziolkowski, M; Zong, Z; Zuccarello, F

    2016-01-01

    We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors of the Pierre Auger Observatory. Such a correlation measurement is a unique feature of a hybrid air-shower observatory with sensitivity to both the electromagnetic and muonic components. It allows an accurate determination of the spread of primary masses in the cosmic-ray flux. Up till now, constraints on the spread of primary masses have been dominated by systematic uncertainties. The present correlation measurement is not affected by systematics in the measurement of the depth of shower maximum or the signal in the water Cherenkov stations. The analysis relies on general characteristics of air showers and is thus robust also with respect to uncertainties in hadronic event generators. The observed correlation in the energy range around the `ankle' at $\\lg(E/{\\...

  12. Neutrino mass and mixing in the 3-3-1 model and S3 flavor symmetry with minimal Higgs content

    CERN Document Server

    Vien, V V

    2014-01-01

    A new S3 flavor model based on $\\mathrm{SU}(3)_C \\otimes \\mathrm{SU}(3)_L \\otimes \\mathrm{U}(1)_X$ gauge symmetry responsible for fermion masses and mixings different from our previous work is constructed. The new feature is a two - dimensional representation of a Higgs anti-sextet under $S_3$ which responsible for neutrino masses and mixings. The neutrinos acquire small masses from only an anti-sextet of $\\mathrm{SU(3)}$ which is in a doublet under $S_3$. If the difference of components of the anti-sextet is regarded as a small perturbation, S3 is equivalently broken into identity, the corresponding neutrino mass mixing matrix acquires the most general form and the model can fit the latest data on neutrino oscillation. This way of the symmetry breaking helps us to reduce a content in the Higgs sector, only one an anti-sextet instead of two as in our previous work. Our results show that the neutrino masses are naturally small and a small deviation from the tri-bimaximal neutrino mixing form can be realized. T...

  13. Determination of fungicides in wine by mixed-mode solid phase extraction and liquid chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Carpinteiro, I; Ramil, M; Rodríguez, I; Cela, R

    2010-11-26

    A novel procedure for the determination of nine selected fungicides (metalaxyl-M, azoxystrobin, myclobutanil, flusilazole, penconazole, tebuconazole, propiconazole, diniconazole and difenoconazole) in wine samples is presented. Sample enrichment and purification is simultaneously performed using mixed-mode, anion exchange and reversed-phase, OASIS MAX solid-phase extraction (SPE) cartridges. Analytes were determined by liquid chromatography coupled to tandem mass spectrometry using atmospheric pressure electrospray ionization (LC-ESI-MS/MS). Parameters affecting the chromatographic determination and the extraction-purification processes were thoroughly investigated. Under optimized conditions, 10 mL of wine were firstly diluted 1:1 with ultrapure water and then passed through the mixed-mode SPE cartridge at a flow of ca. 5 mLmin(-1). After a washing step with 5 mL of an aqueous NH(4)OH solution (5%, w:v), analytes were recovered with just 1 mL of methanol and injected in the LC-MS/MS system without any additional purification. The selective extraction process avoided significant changes in the ionization efficiency for red and white wine extracts in comparison with pure standards in methanol. Performance of the method was good in terms of precision (RSDs72%, determined against pure standards in methanol) reporting method LOQs in the range of 0.01-0.79 ngmL(-1) for target compounds, which are far below the EU maxima residue levels (MRLs) for fungicides in vinification grapes and wine. Several commercial wines from different geographic areas in Spain were analyzed. In most samples, metalaxyl-M and azoxystrobin were found at concentrations up to several ngmL(-1). Copyright © 2010 Elsevier B.V. All rights reserved.

  14. The Barents Sea frontal zones and water masses variability (1980-2011)

    Science.gov (United States)

    Oziel, L.; Sirven, J.; Gascard, J.-C.

    2016-01-01

    The polar front separates the warm and saline Atlantic Water entering the southern Barents Sea from the cold and fresh Arctic Water located in the north. These water masses can mix together (mainly in the center of the Barents Sea), be cooled by the atmosphere and receive salt because of brine release; these processes generate dense water in winter, which then cascades into the Arctic Ocean to form the Arctic Intermediate Water. To study the interannual variability and evolution of the frontal zones and the corresponding variations of the water masses, we have merged data from the International Council for the Exploration of the Sea and the Arctic and Antarctic Research Institute and have built a new database, which covers the 1980-2011 period. The summer data were interpolated on a regular grid. A probability density function is used to show that the polar front splits into two branches east of 32° E where the topographic constraint weakens. Two fronts can then be identified: the Northern Front is associated with strong salinity gradients and the Southern Front with temperature gradients. Both fronts enclose the denser Barents Sea Water. The interannual variability of the water masses is apparent in the observed data and is linked to that of the ice cover. The frontal zones variability is found by using data from a general circulation model. The link with the atmospheric variability, represented here by the Arctic Oscillation, is not clear. However, model results suggest that such a link could be validated if winter data were taken into account. A strong trend appears: the Atlantic Water (Arctic Water) occupies a larger (smaller) volume of the Barents Sea. This trend amplifies during the last decade and the model study suggests that this could be accompanied by a northwards displacement of the Southern Front in the eastern part of the Barents Sea. The results are less clear for the Northern Front. The observations show that the volume of the Barents Sea Water

  15. The water masses between Mindanao and New Guinea

    Science.gov (United States)

    Kashino, Yuji; Aoyama, Michio; Kawano, Takeshi; Hendiarti, Nani; Syaefudin; Anantasena, Yudi; Muneyama, Kei; Watanabe, Hidetoshi

    1996-05-01

    Water masses between Mindanao and New Guinea are investigated, using hydrographic data, during two R/V Kaiyo World Ocean Circulation Experiment cruises conducted in October 1992 and February 1994. The analysis of this data indicates that the South Pacific Tropical Water (SPTW), which is formed in the southern hemisphere, reached the area of Morotai Island in 1992 and farther north in 1994. The Antarctic Intermediate Water (AAIW) exists in the southwestern area of the southernmost Philippine Sea. There is northeastward flow between Talaud Islands and Morotai Island, which is probably a part of the retroflection of the Mindanao Current. The remnant of the North Pacific Intermediate Water, advected by the flow from the Celebes Sea, was found in 1992. The New Guinea Coastal Undercurrent, transporting SPTW and AAIW from the southern hemisphere, is divided into at least two parts because the retroflection of the Mindanao Current prevents its shallow part from reaching farther north; the shallow part of SPTW turns eastward as a source water of North Equatorial Countercurrent and retroflects toward the southeast. AAIW and the lower part of SPTW flow northward and seem to be linked with the Mindanao Undercurrent.

  16. Mass size distribution of particle-bound water

    Science.gov (United States)

    Canepari, S.; Simonetti, G.; Perrino, C.

    2017-09-01

    The thermal-ramp Karl-Fisher method (tr-KF) for the determination of PM-bound water has been applied to size-segregated PM samples collected in areas subjected to different environmental conditions (protracted atmospheric stability, desert dust intrusion, urban atmosphere). This method, based on the use of a thermal ramp for the desorption of water from PM samples and the subsequent analysis by the coulometric KF technique, had been previously shown to differentiate water contributes retained with different strength and associated to different chemical components in the atmospheric aerosol. The application of the method to size-segregated samples has revealed that water showed a typical mass size distribution in each one of the three environmental situations that were taken into consideration. A very similar size distribution was shown by the chemical PM components that prevailed during each event: ammonium nitrate in the case of atmospheric stability, crustal species in the case of desert dust, road-dust components in the case of urban sites. The shape of the tr-KF curve varied according to the size of the collected particles. Considering the size ranges that better characterize the event (fine fraction for atmospheric stability, coarse fraction for dust intrusion, bi-modal distribution for urban dust), this shape is coherent with the typical tr-KF shape shown by water bound to the chemical species that predominate in the same PM size range (ammonium nitrate, crustal species, secondary/combustion species - road dust components).

  17. Effects of the Water in Mixed Solvent on the Epoxidation Reaction of Propylene with TS-1 Catalyst

    Institute of Scientific and Technical Information of China (English)

    苏泉声; 王彪; 张玉梅; 王华平

    2001-01-01

    The epoxidation reaction of propylene and hydrogen peroxide with zeolite catalyst containing titaniumsilicalite (TS-1)has been studied, and the reaction in the mixed solvent of water/methanol has been discussed. It is shown that the selective of epoxidation propylene decreases while the selective of propylene glycol increases, when the water content increases in the mixed solvent of methanol/water.

  18. Neutrino masses and tribimaximal mixing in Minimal renormalizable SUSY SU(5) Grand Unified Model with A4 Flavor symmetry

    CERN Document Server

    Ciafaloni, Paolo; Torrente-Lujan, Emilio; Urbano, Alfredo

    2009-01-01

    We analyze all possible extensions of the recently proposed minimal renormalizable SUSY SU(5) grand unified model with the inclusion of an additional A4 flavor symmetry. We find that there are 5 possible Cases but only one of them is phenomenologically interesting. We develop in detail such Case and we show how the fermion masses and mixing angles come out. As prediction we obtain the neutrino masses of order of 0.1 eV with an inverted hierarchy.

  19. Convective Mixing in Distal Pipes Exacerbates Legionella pneumophila Growth in Hot Water Plumbing

    Directory of Open Access Journals (Sweden)

    William J. Rhoads

    2016-03-01

    Full Text Available Legionella pneumophila is known to proliferate in hot water plumbing systems, but little is known about the specific physicochemical factors that contribute to its regrowth. Here, L. pneumophila trends were examined in controlled, replicated pilot-scale hot water systems with continuous recirculation lines subject to two water heater settings (40 °C and 58 °C and three distal tap water use frequencies (high, medium, and low with two pipe configurations (oriented upward to promote convective mixing with the recirculating line and downward to prevent it. Water heater temperature setting determined where L. pneumophila regrowth occurred in each system, with an increase of up to 4.4 log gene copies/mL in the 40 °C system tank and recirculating line relative to influent water compared to only 2.5 log gene copies/mL regrowth in the 58 °C system. Distal pipes without convective mixing cooled to room temperature (23–24 °C during periods of no water use, but pipes with convective mixing equilibrated to 30.5 °C in the 40 °C system and 38.8 °C in the 58 °C system. Corresponding with known temperature effects on L. pneumophila growth and enhanced delivery of nutrients, distal pipes with convective mixing had on average 0.2 log more gene copies/mL in the 40 °C system and 0.8 log more gene copies/mL in the 58 °C system. Importantly, this work demonstrated the potential for thermal control strategies to be undermined by distal taps in general, and convective mixing in particular.

  20. Nitrogen patterns in subsurface waters of the Yzeron stream: effect of combined sewer overflows and subsurface-surface water mixing.

    Science.gov (United States)

    Aucour, A M; Bariac, T; Breil, P; Namour, P; Schmitt, L; Gnouma, R; Zuddas, P

    2013-01-01

    Urbanization subjects streams to increased nitrogen loads. Therefore studying nitrogen forms at the interface between urban stream and groundwater is important for water resource management. In this study we report results on water δ(18)O and nitrogen forms in subsurface waters of a stream (Yzeron, France). The sites studied were located upstream and downstream of combined sewer overflows (CSO) in a rural area and a periurban area, respectively. Water δ(18)O allowed us to follow the mixing of subsurface water with surface water. Dissolved organic nitrogen and organic carbon of fine sediment increased by 20-30% between rural and periurban subsurface waters in the cold season, under high flow. The highest nitrate levels were observed in rural subsurface waters in the cold season. The lowest nitrate levels were found in periurban subsurface waters in the warm season, under low flow. They corresponded to slow exchange of subsurface waters with channel water. Thus reduced exchange between surface and subsurface waters and organic-matter-rich input seemed to favor nitrate reduction in the downstream, periurban, subsurface waters impacted by CSO.

  1. The water footprint of biofuel produced from forest wood residue via a mixed alcohol gasification process

    Science.gov (United States)

    Chiu, Yi-Wen; Wu, May

    2013-09-01

    Forest residue has been proposed as a feasible candidate for cellulosic biofuels. However, the number of studies assessing its water use remains limited. This work aims to analyze the impacts of forest-based biofuel on water resources and quality by using a water footprint approach. A method established here is tailored to the production system, which includes softwood, hardwood, and short-rotation woody crops. The method is then applied to selected areas in the southeastern region of the United States to quantify the county-level water footprint of the biofuel produced via a mixed alcohol gasification process, under several logistic systems, and at various refinery scales. The results indicate that the blue water sourced from surface or groundwater is minimal, at 2.4 liters per liter of biofuel (l/l). The regional-average green water (rainfall) footprint falls between 400 and 443 l/l. The biofuel pathway appears to have a low nitrogen grey water footprint averaging 25 l/l at the regional level, indicating minimal impacts on water quality. Feedstock mix plays a key role in determining the magnitude and the spatial distribution of the water footprint in these regions. Compared with other potential feedstock, forest wood residue shows promise with its low blue and grey water footprint.

  2. Forage mass and the nutritive value of pastures mixed with forage peanut and red clover

    Directory of Open Access Journals (Sweden)

    Ricardo Lima de Azevedo Junior

    2012-04-01

    Full Text Available The objective of this research was to estimate three pasture-based systems mixed with elephantgrass + spontaneous growth species, annual ryegrass, for pasture-based system 1; elephantgrass + spontaneous growth species + forage peanut, for pasture-based system 2; and elephantgrass + spontaneous growth species + annual ryegrass + red clover, for pasture-based system 3. Elephantgrass was planted in rows 4 m apart from each other. During the cool-season, annual ryegrass was sown in the alleys between the rows of elephantgrass; forage peanut and red clover were sown in the alleys between the elephantgrass according to the respective treatment. The experimental design was totally randomized in the three treatments (pasture-based systems, two replicates (paddocks in completely split-plot time (grazing cycles. Holstein cows receiving 5.5 kg-daily complementary concentrate feed were used in the evaluation. Pre-grazing forage mass, botanical composition and stocking rate were evaluated. Samples of simulated grazing were collected to analyze organic matter (OM, neutral detergent fiber (NDF, crude protein (CP and organic matter in situ digestibility (OMISD. Nine grazing cycles were performed during the experimental period (341 days. The average dry matter values for pre-grazing and stocking rate were 3.34; 3.46; 3.79 t/ha, and 3.28; 3.34; 3.60 AU/ha for each respective pasture-based system. Similar results were observed between the pasture-based systems for OM, NDF, CP and OMISD. Considering forage mass, stocking rate and nutritive value, the pasture-based system intercropped with forage legumes presented better performance.

  3. Interannual variability of the southern Yellow Sea Cold Water Mass

    Institute of Scientific and Technical Information of China (English)

    胡敦欣; 王庆业

    2004-01-01

    Temperature data collected in the sections of 34°N, 35°N and 36°N in August from 1975 through2003 were analyzed using Empirical Orthogonal Function (EOF) to investigate interannual variability of the southern Yellow Sea Cold Water Mass (YSCWM). The first mode (EOF1) reveals variations of basin-wide thermocline depth, which is mainly caused by surface heating. The second mode (EOF2) presents fluctuations of vertical circulation, resulting mainly from interannual variability of cold front intensity. In addition, it is found that the upward extent of upwelling in the cold front is basically determined by wind stress curl and the zonal position of the warm water center in the southern Yellow Sea is correlated with spatial difference of net heat flux.

  4. Multiple scattering of light by water cloud droplets with external and internal mixing of black carbon aerosols

    Institute of Scientific and Technical Information of China (English)

    Wang Hai-Hua; Sun Xian-Ming

    2012-01-01

    The mixture of water cloud droplets with black carbon impurities is modeled by external and internal mixing models.The internal mixing model is modeled with a two-layered sphere(water cloud droplets containing black carbon(BC)inclusions),and tihe single scattering and absorption characteristics are calculated at the visible wavelength of 0.55 μm by using the Lorenz Mie theory.The external mixing model is developed assuming that the same amount of BC particles are mixed with the water droplets externally.The multiple scattering characteristics we computed by using the Monte Carlo method.The results show that when the size of the BC aerosol is small,the reflection intensity of the internal mixing model is bigger than that of the external mixing model.However,if the size of the BC aerosol is big,the absorption of the internal mixing model will be larger than that of the external mixing model.

  5. Dynamics of water evaporation from saline porous media with mixed wettability

    Science.gov (United States)

    Bergstad, Mina; Shokri, Nima

    2016-04-01

    Understanding of the dynamics of salt transport and precipitation in porous media during evaporation is of crucial concern in various environmental and hydrological applications such as soil salinization, rock weathering, terrestrial ecosystem functioning, microbiological activities and biodiversity in vadose zone. Vegetation, plant growth and soil organisms can be severely limited in salt-affected land. This process is influenced by the complex interaction among atmospheric conditions, transport properties of porous media and properties of the evaporating solution (1-5). We investigated effects of mixed wettability conditions on salt precipitation during evaporation from saline porous media. To do so, we conducted a series of evaporation experiments with sand mixtures containing different fractions of hydrophobic grains saturated with NaCl solutions. The dynamics of salt precipitation at the surface of sand columns (mounted on digital balances to record the evaporation curves) as well as the displacement of the receding drying front (the interface between wet and partially wet zone) were recorded using an automatic imaging system at well-defined time intervals. The experiments were conducted with sand packs containing 0, 25, 40, 50, 65, and 80% fraction of hydrophobic grains. All experiments were conducted in an environmental chamber in which the relative humidity and ambient temperature were kept constant at 30% and 30 C, respectively. Our results show that partial wettability conditions had minor impacts on the evaporative mass losses from saline sand packs due to the presence of salt. This is significantly different than what is normally observed during evaporation from mixed wettability porous media saturated with pure water (6). In our experiments, increasing the fraction of hydrophobic grains did not result in any notable reduction of the evaporative mass losses from saline porous media. Our results show that the presence of hydrophobic grains on the surface

  6. On the role of mass diffusion and fluid dynamics in the dissipation of chunk mix

    Energy Technology Data Exchange (ETDEWEB)

    Cloutman, L D

    1999-03-01

    When numerically simulating multicomponent turbulent flows, subgrid-scale diffusion of chemical species requires closure. This mixing of chemical species at the molecular level dissipates concentration uctuations, which limits possible demixing and affects other pro- cesses such as energy transport and reaction rates at the subgrid level. We discuss some of the physical processes that reduce small chunks of a heavy material in a light gas or plasma to a mixture at the atomic level. Preliminary direct numerical simulations of these processes are presented using the dissipation of small spheres of heavy gas in a light gas as an archetypal process in turbulent micromixing in multicomponent ows, including classical uid instabilities and shock ejecta. We use a detailed approach for the diffusion process, directly solving the Stefan-Maxwell equations for the mass fluxes. We discuss the dissipa- tion of a 24µm sphere of xenon in helium in three different flow regimes, and we present suggestions for future work intended as input to improved subgrid-scale turbulence models.

  7. The Higgs boson mass constraint and the CP even-CP odd Higgs boson mixing in an MSSM extension

    CERN Document Server

    Ibrahim, Tarek; Zorik, Anas

    2016-01-01

    One loop contributions to the CP even-CP odd Higgs boson mixings arising from contributions due to exchange of a vectorlike multiplet are computed under the Higgs boson mass constraint. The vectorlike multiplet consists of a fourth generation of quarks and a mirror generation. This sector brings in new CP phases which can be large consistent with EDM constraints. In this work we compute the contributions from the exchange of quarks and mirror quarks $t_{4L}, t_{4R}, T_{L}, T_{R}$, and their scalar partners, the squarks and the mirror squarks. The effect of their contributions to the Higgs boson masses and mixings are computed and analyzed. The possibility of measuring the effects of mixing of CP even and CP odd Higgs in experiment is discussed. It is shown that the branching ratios of the Higgs bosons into fermion pairs are sensitive to new physics and specifically to CP phases.

  8. Understanding Flow Pathways, Mixing and Transit Times for Water Quality Modelling

    Science.gov (United States)

    Dunn, S. M.; Bacon, J. R.; Soulsby, C.; Tetzlaff, D.

    2007-12-01

    Water quality modelling requires representation of the physical processes controlling the movement of solutes and particulates at an appropriate level of detail to address the objective of the model simulations. To understand and develop mitigation strategies for diffuse pollution at catchment scales, it is necessary for models to be able to represent the sources and age of water reaching rivers at different times. Experimental and modelling studies undertaken on several catchments in the north east of Scotland have used natural hydrochemical and isotopic tracers as a means of obtaining spatially integrated information about mixing processes. Methods for obtaining and integrating appropriate data are considered together with the implications of neglecting it. The tracer data have been incorporated in a conceptual hydrological model to study the sensitivity of the modelled tracer response to factors that may not affect runoff simulations but do affect mixing and transit times of the water. Results from the studies have shown how model structural and parameter uncertainties can lead to errors in the representation of: the flow pathways of water; the degree to which these flow pathways have mixed and the length of time for which water has been stored within the soil / groundwater system. It has been found to be difficult to eliminate structural uncertainty regarding the mechanisms of mixing, and parameter uncertainty regarding the role of groundwater. Simulations of nitrate pollution, resulting from the application of agricultural fertilisers, have been undertaken to demonstrate the sensitivity of water quality simulations to the potential errors in physical transport mechanisms, inherent in models that fail to account correctly for flow pathways, mixing and transit times.

  9. The Role of Mixing in the Mechanisms of Water Bloom by Microcystis spp.

    OpenAIRE

    SIHOTANG, CLEMENS; Okino, Tokio

    1985-01-01

    Studies on the role of water mixing in the mechanisms of water bloom by Microcystis spp., which were composed from the three species, M. aeruginosa, M. viridis and M. wesenbergii, were conducted during the summer of 1983. Microcystis spp. are a species of blue-green algae that appears regularly in the summer in Lake Suwa, Japan. Centrifugation was used in order to separate Microcystis spp. from other phytoplankton. Thus, the floating part of the centrifugal tube was occupied by Microcystis sp...

  10. Retained gas sampler extractor mixing and mass transfer rate study: Experimental and simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Recknagle, K.P.; Bates, J.M.; Shekarriz, A.

    1997-11-01

    Research staff at Pacific Northwest National Laboratory conducted experimental testing and computer simulations of the impeller-stirred Retained Gas Sampler (RGS) gas extractor system. This work was performed to verify experimentally the effectiveness of the extractor at mixing viscous fluids of both Newtonian and non-Newtonian rheology representative of Hanford single- and double-shell wastes, respectively. Developing the computational models and validating their results by comparing them with experimental results would enable simulations of the mixing process for a range of fluid properties and mixing speeds. Five tests were performed with a full-scale, optically transparent model extractor to provide the data needed to compare mixing times for fluid rheology, mixer rotational direction, and mixing speed variation. The computer model was developed and exercised to simulate the tests. The tests demonstrated that rotational direction of the pitched impeller blades was not as important as fluid rheology in determining mixing time. The Newtonian fluid required at least six hours to mix at the hot cell operating speed of 3 rpm, and the non-Newtonian fluid required at least 46 hours at 3 rpm to become significantly mixed. In the non-Newtonian fluid tests, stagnant regions within the fluid sometimes required days to be fully mixed. Higher-speed (30 rpm) testing showed that the laminar mixing time was correlated to mixing speed. The tests demonstrated that, using the RGS extractor and current procedures, complete mixing of the waste samples in the hot cell should not be expected. The computer simulation of Newtonian fluid mixing gave results comparable to the test while simulation of non-Newtonian fluid mixing would require further development. In light of the laboratory test results, detailed parametric analysis of the mixing process was not performed.

  11. Hurricanes Ingrid and Manuel (2013) and their impact on the salinity of the Meteoric Water Mass, Quintana Roo, Mexico

    Science.gov (United States)

    Coutino, Aaron; Stastna, Marek; Kovacs, Shawn; Reinhardt, Eduard

    2017-08-01

    We report on measurements of the salinity and temperature in the Yax Chen cave system on the Yuacatan peninsula. This paper is submitted together with Kovacs et al. (2017). Kovacs et al. focuses on the salinity levels of the meteoric lens, while this paper uses the observed results to elucidate the hydrodynamics. The cave passages have water depths on the order of 10 m, with flow on the order of ten centimeters a second, and as such is a hydrodynamic, as opposed to a porous, system. The measurements reveal that episodes of significant mixing between the fresh meteoric lens and the underlying salty water are driven by meteorological events (e.g., Hurricane Rina in 2011, and the twin Hurricanes Ingrid and Manuel in 2013). We find evidence that after the hurricanes in 2013, the water column remains unstable for several months. Through wavelet analysis, we find that the marine Water Mass (WM) exhibits much less low period activity compared to the meteoric WM. We hypothesize that the open cenotes are locations of high mixing intensity, with turbulent fronts propagating away from the sites of direct mixing into the cave network. We perform laboratory experiments and numerical simulations to explore this phenomenon, and find that mixing preferentially occurs on the flanks of regions of strong, stable density stratification (i.e., on the periphery of pycnoclines), and leads to entrainment of fluid into the turbulent region. Using high resolution direct numerical simulation, we explore the detailed manner in which turbulent entrainment can drive flow toward the mixing region, and lead to mixing of passive tracers. Finally, we discuss the implications of these results for the mixing of passive tracers, such as suspended chemicals.

  12. Interaction between seabed morphology and water masses around the seamounts on the Motril Marginal Plateau (Alboran Sea, Western Mediterranean)

    Science.gov (United States)

    Palomino, Desirée; Vázquez, Juan-Tomás; Ercilla, Gemma; Alonso, Belén; López-González, Nieves; Díaz-Del-Río, Víctor

    2011-12-01

    The seabed morphology in the vicinity of the seamounts on the Motril Marginal Plateau (northern Alboran Sea) was investigated using high-resolution (sparker) and very high-resolution (TOPAS) seismic reflection profiles and multibeam bathymetry. The aim of the study was to determine the recent geological processes, and in particular those that control the contourite depositional system associated with the intermediate and deep Mediterranean water masses. Six groups of morphological features were identified: structural features (seamount tops, tectonic depressions), fluid escape-related features (pockmarks), mass-movement features (gullies, slides), bottom-current features (moats, scour marks, terraces, elongated and separated drifts, plastered drifts, confined drifts, sheeted drifts), mixed features (ridges) and biogenic features (including evidence of (dead) cold water corals such as Lophelia pertusa and Madrepora oculata). The main processes controlling the formation of these features are recent tectonic activity and the interaction of Mediterranean water masses with the seafloor topography. Seamounts act as topographic barriers that affect the pathway and velocity of the deep Mediterranean water masses, which are divided into strands that interact with the surrounding seafloor. The influence of the intermediate Mediterranean water mass, by contrast, is restricted mainly to the tops of the seamounts. Sediment instability and fluid-escape processes play a minor role, their occurrence being probably related to seismicity.

  13. Factors affecting alcohol-water pervaporation performance of hydrophobic zeolite-silicone rubber mixed matrix membranes

    Science.gov (United States)

    Mixed matrix membranes (MMMs) consisting of ZSM-5 zeolite particles dispersed in silicone rubber exhibited ethanol-water pervaporation permselectivities up to 5 times that of silicone rubber alone and 3 times higher than simple vapor-liquid equilibrium (VLE). A number of conditi...

  14. Modeling rapid mass movements using the shallow water equations

    Directory of Open Access Journals (Sweden)

    S. Hergarten

    2014-11-01

    Full Text Available We propose a new method to model rapid mass movements on complex topography using the shallow water equations in Cartesian coordinates. These equations are the widely used standard approximation for the flow of water in rivers and shallow lakes, but the main prerequisite for their application – an almost horizontal fluid table – is in general not satisfied for avalanches and debris flows in steep terrain. Therefore, we have developed appropriate correction terms for large topographic gradients. In this study we present the mathematical formulation of these correction terms and their implementation in the open source flow solver GERRIS. This novel approach is evaluated by simulating avalanches on synthetic and finally natural topographies and the widely used Voellmy flow resistance law. The results are tested against analytical solutions and the commercial avalanche model RAMMS. The overall results are in excellent agreement with the reference system RAMMS, and the deviations between the different models are far below the uncertainties in the determination of the relevant fluid parameters and involved avalanche volumes in reality. As this code is freely available and open source, it can be easily extended by additional fluid models or source areas, making this model suitable for simulating several types of rapid mass movements. It therefore provides a valuable tool assisting regional scale natural hazard studies.

  15. Numerical Evaluation of Fluid Mixing Phenomena in Boiling Water Reactor Using Advanced Interface Tracking Method

    Science.gov (United States)

    Yoshida, Hiroyuki; Takase, Kazuyuki

    Thermal-hydraulic design of the current boiling water reactor (BWR) is performed with the subchannel analysis codes which incorporated the correlations based on empirical results including actual-size tests. Then, for the Innovative Water Reactor for Flexible Fuel Cycle (FLWR) core, an actual size test of an embodiment of its design is required to confirm or modify such correlations. In this situation, development of a method that enables the thermal-hydraulic design of nuclear reactors without these actual size tests is desired, because these tests take a long time and entail great cost. For this reason, we developed an advanced thermal-hydraulic design method for FLWRs using innovative two-phase flow simulation technology. In this study, a detailed Two-Phase Flow simulation code using advanced Interface Tracking method: TPFIT is developed to calculate the detailed information of the two-phase flow. In this paper, firstly, we tried to verify the TPFIT code by comparing it with the existing 2-channel air-water mixing experimental results. Secondary, the TPFIT code was applied to simulation of steam-water two-phase flow in a model of two subchannels of a current BWRs and FLWRs rod bundle. The fluid mixing was observed at a gap between the subchannels. The existing two-phase flow correlation for fluid mixing is evaluated using detailed numerical simulation data. This data indicates that pressure difference between fluid channels is responsible for the fluid mixing, and thus the effects of the time average pressure difference and fluctuations must be incorporated in the two-phase flow correlation for fluid mixing. When inlet quality ratio of subchannels is relatively large, it is understood that evaluation precision of the existing two-phase flow correlations for fluid mixing are relatively low.

  16. Mixing Cell Model: A One-Dimensional Numerical Model for Assessment of Water Flow and Contaminant Transport in the Unsaturated Zone

    Energy Technology Data Exchange (ETDEWEB)

    A. S. Rood

    2010-10-01

    This report describes the Mixing Cell Model code, a one-dimensional model for water flow and solute transport in the unsaturated zone under steady-state or transient flow conditions. The model is based on the principles and assumptions underlying mixing cell model formulations. The unsaturated zone is discretized into a series of independent mixing cells. Each cell may have unique hydrologic, lithologic, and sorptive properties. Ordinary differential equations describe the material (water and solute) balance within each cell. Water flow equations are derived from the continuity equation assuming that unit-gradient conditions exist at all times in each cell. Pressure gradients are considered implicitly through model discretization. Unsaturated hydraulic conductivity and moisture contents are determined by the material-specific moisture characteristic curves. Solute transport processes include explicit treatment of advective processes, first-order chain decay, and linear sorption reactions. Dispersion is addressed through implicit and explicit dispersion. Implicit dispersion is an inherent feature of all mixing cell models and originates from the formulation of the problem in terms of mass balance around fully mixed volume elements. Expressions are provided that relate implicit dispersion to the physical dispersion of the system. Two FORTRAN codes were developed to solve the water flow and solute transport equations: (1) the Mixing-Cell Model for Flow (MCMF) solves transient water flow problems and (2) the Mixing Cell Model for Transport (MCMT) solves the solute transport problem. The transient water flow problem is typically solved first by estimating the water flux through each cell in the model domain as a function of time using the MCMF code. These data are stored in either ASCII or binary files that are later read by the solute transport code (MCMT). Code output includes solute pore water concentrations, water and solute inventories in each cell and at each

  17. Mixing Cell Model: A One-Dimensional Numerical Model for Assessment of Water Flow and Contaminant Transport in the Unsaturated Zone

    Energy Technology Data Exchange (ETDEWEB)

    A. S. Rood

    2009-04-01

    This report describes the Mixing Cell Model code, a one-dimensional model for water flow and solute transport in the unsaturated zone under steady-state or transient flow conditions. The model is based on the principles and assumptions underlying mixing cell model formulations. The unsaturated zone is discretized into a series of independent mixing cells. Each cell may have unique hydrologic, lithologic, and sorptive properties. Ordinary differential equations describe the material (water and solute) balance within each cell. Water flow equations are derived from the continuity equation assuming that unit-gradient conditions exist at all times in each cell. Pressure gradients are considered implicitly through model discretization. Unsaturated hydraulic conductivity and moisture contents are determined by the material-specific moisture characteristic curves. Solute transport processes include explicit treatment of advective processes, first-order chain decay, and linear sorption reactions. Dispersion is addressed through implicit and explicit dispersion. Implicit dispersion is an inherent feature of all mixing cell models and originates from the formulation of the problem in terms of mass balance around fully mixed volume elements. Expressions are provided that relate implicit dispersion to the physical dispersion of the system. Two FORTRAN codes were developed to solve the water flow and solute transport equations: (1) the Mixing-Cell Model for Flow (MCMF) solves transient water flow problems and (2) the Mixing Cell Model for Transport (MCMT) solves the solute transport problem. The transient water flow problem is typically solved first by estimating the water flux through each cell in the model domain as a function of time using the MCMF code. These data are stored in either ASCII or binary files that are later read by the solute transport code (MCMT). Code output includes solute pore water concentrations, water and solute inventories in each cell and at each

  18. Fermion masses and mixing in a 4+1-dimensional SU(5) domain-wall brane model

    CERN Document Server

    Callen, Benjamin D

    2010-01-01

    We study the fermion mass and mixing hierarchy problems within the context of the SU(5) 4+1d domain-wall brane model of Davies, George and Volkas. In this model, the ordinary fermion mass relations of SU(5) grand unified theories are avoided since the masses are proportional to overlap integrals of the profiles of the electroweak Higgs and the chiral components of each fermion, which are split into different 3+1d hyperplanes according to their hypercharges. We show that the fermion mass hierarchy without electroweak mixing can be generated naturally from these splittings, that generation of the CKM matrix looks promising, and that the Cabibbo angle along with the mass hierarchy can be generated for the case of Majorana neutrinos from a more modest hierarchy of parameters. We also show that under some assumptions made on the parameter space, the generation of realistic lepton mixing angles is not possible without fine-tuning, which argues for a flavour symmetry to enforce the required relations.

  19. "Mixed-solvency approach" - Boon for solubilization of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Maheshwari R

    2010-01-01

    Full Text Available Based on a large number of experiments on solubilization of poorly water-soluble drugs, the author is of the opinion that hydrotropy is another type of cosolvency and all water-soluble substances whether liquids, solids, or gases may act as solubilizers for poorly water-soluble drugs. In the present investigation, a mixed-solvency approach has been utilized for solubility enhancement of poorly water-soluble drug, salicylic acid (as a model drug. Sixteen blends (having total 40% w/v strength of solubilizers containing various solubilizers among the commonly used hydrotropes (urea and sodium citrate, cosolvents (glycerin, propylene glycol, PEG 300 and PEG 400, and water-soluble solids (PEG 4000 and PEG 6000 were made to study the influence on solubility of salicylic acid. Twelve blends were found to increase the solubility of salicylic acid, synergistically. This approach shall prove a boon in pharmaceutical field to develop various formulations of poorly water-soluble drugs by combining various water-soluble excipients in safe concentrations to give a strong solution (say 25% w/v or so to produce a desirable aqueous solubility of poorly water-soluble drugs. In the present investigation, the mixed-solvency approach has been employed to analyze salicylic acid in the bulk drug sample (using six blends precluding the use of organic solvents (a way to green chemistry.

  20. Mixing height over water and its role on the correlation between temperature and humidity fluctuations in the unstable surface layer

    DEFF Research Database (Denmark)

    Sempreviva, A.M.; Gryning, Sven-Erik

    2000-01-01

    Results from an experimental investigation of the mixing height over inner Danish waters carried out from September 1990 to October 1992, are discussed. The statistical analysis of the mixed-layer height (z(i)) over the sea does not exhibit the daily variation that is characteristic of the mixed ...

  1. Sensitive detection of n-alkanes using a mixed ionization mode proton-transfer-reaction mass spectrometer

    Science.gov (United States)

    Amador-Muñoz, Omar; Misztal, Pawel K.; Weber, Robin; Worton, David R.; Zhang, Haofei; Drozd, Greg; Goldstein, Allen H.

    2016-11-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) is a technique that is widely used to detect volatile organic compounds (VOCs) with proton affinities higher than water. However, n-alkanes generally have a lower proton affinity than water and therefore proton transfer (PT) by reaction with H3O+ is not an effective mechanism for their detection. In this study, we developed a method using a conventional PTR-MS to detect n-alkanes by optimizing ion source and drift tube conditions to vary the relative amounts of different primary ions (H3O+, O2+, NO+) in the reaction chamber (drift tube). There are very few studies on O2+ detection of alkanes and the mixed mode has never been proposed before. We determined the optimum conditions and the resulting reaction mechanisms, allowing detection of n-alkanes from n-pentane to n-tridecane. These compounds are mostly emitted by evaporative/combustion process from fossil fuel use. The charge transfer (CT) mechanism observed with O2+ was the main reaction channel for n-heptane and longer n-alkanes, while for n-pentane and n-hexane the main reaction channel was hydride abstraction (HA). Maximum sensitivities were obtained at low E / N ratios (83 Td), low water flow (2 sccm) and high O2+ / NO+ ratios (Uso = 180 V). Isotopic 13C contribution was taken into account by subtracting fractions of the preceding 12C ion signal based on the number of carbon atoms and the natural abundance of 13C (i.e., 5.6 % for n-pentane and 14.5 % for n-tridecane). After accounting for isotopic distributions, we found that PT cannot be observed for n-alkanes smaller than n-decane. Instead, protonated water clusters of n-alkanes (M ṡ H3O+) species were observed with higher abundance using lower O2+ and higher water cluster fractions. M ṡ H3O+ species are probably the source for the M + H+ species observed from n-decane to n-tridecane. Normalized sensitivities to O2+ or to the sum of O2++ NO+ were determined to be a good metric with which to

  2. Effective Momentum and heat flux models for simulation of stratification and mixing in a large pool of water

    Energy Technology Data Exchange (ETDEWEB)

    Hua Li; Villanueva, W.; Kudinov, P. [Royal Institute of Technology (KTH). Div. of Nuclear Power Safety, Stockholm (Sweden)

    2012-06-15

    Performance of a boiling water reactor (BWR) containment is mostly determined by reliable operation of pressure suppression pool which serves as a heat sink to cool and condense steam released from the core vessel. Thermal stratification in the pool can significantly impede the pool's pressure suppression capacity. A source of momentum is required in order to break stratification and mix the pool. It is important to have reliable prediction of transient development of stratification and mixing in the pool in different regimes of steam injection. Previously, we have proposed to model the effect of steam injection on the mixing and stratification with the Effective Heat Source (EHS) and the Effective Momentum Source (EMS) models. The EHS model is used to provide thermal effect of steam injection on the pool, preserving heat and mass balance. The EMS model is used to simulate momentum induced by steam injection in different flow regimes. The EMS model is based on the combination of (1) synthetic jet theory, which predicts effective momentum if amplitude and frequency of flow oscillations in the pipe are given, and (2) model proposed by Aya and Nariai for prediction of the amplitude and frequency of oscillations at a given pool temperature and steam mass flux. The complete EHS/EMS models only require the steam mass flux, initial pool bulk temperature, and design-specific parameters, to predict thermal stratification and mixing in a pressure suppression pool. In this work we use EHS/EMS models implemented in containment thermal hydraulic code GOTHIC. The POOLEX/PPOOLEX experiments (Lappeenranta University of Technology, Finland) are utilized, to (a) quantify errors due to GOTHIC's physical models and numerical schemes, (b) propose necessary improvements in GOTHIC sub-grid scale modeling, and (c) validate our proposed models. Specifically the data from POOLEX STB-21 and PPOOLEX STR-03 and STR-04 tests are used for validation of the EHS and EMS models in this

  3. Spatial distribution and intra-annual variability of water masses on the Eastern Gulf of Cadiz seabed

    Science.gov (United States)

    Bellanco, M. J.; Sánchez-Leal, R. F.

    2016-10-01

    This paper presents the spatial distribution and intra-annual variability of seabed hydrography in the Eastern Gulf of Cadiz based on more than 10 years of near-bottom CTD observations. Well-defined water masses and a variety of mixing products are persistently sorted along three bathymetric areas occupying particular depth intervals: (i) inner shelf waters (Gibraltar driven both by an elevated MOW and a less stratified ENACW could explain the winter salinification of most of the grounds deeper than 250 m.

  4. Natural COnvective Heat and Mass Transfer on a Vertical Heated Plate for Water Flow Containing Metal Corrosion Particles

    Institute of Scientific and Technical Information of China (English)

    Pei-xueJiang; Ze-peiRen; 等

    1992-01-01

    Corrosion products of structural materials when contained in water usually are in two states:soluble state and colloidal particles with dimeter about 10-3-10-1um,Deposits of such corrosion products on tube surfaces under high pressure will jeopardize the operating economy of power plant equipment and even esult in accidents.A numerical study is reported in this paper of the natural convective heat and mass transfer on a vertical heated plate subject to the flrst or mixed kind of boundary conditions for high-pressure water(P=17MPa) containing metal corrosion products with consideration of varialbe thermophysical properties.

  5. Optics of Water Cloud Droplets Mixed with Black-Carbon Aerosols

    Science.gov (United States)

    Mishchenko, Michael I.; Liu, Li; Cairns, Brian; Mackowski, Daniel W.

    2014-01-01

    We use the recently extended superposition T-matrix method to calculate scattering and absorption properties of micrometer-sized water droplets contaminated by black carbon. Our numerically exact results reveal that, depending on the mode of soot-water mixing, the soot specific absorption can vary by a factor exceeding 6.5. The specific absorption is maximized when the soot material is quasi-uniformly distributed throughout the droplet interior in the form of numerous small monomers. The range of mixing scenarios captured by our computations implies a wide range of remote sensing and radiation budget implications of the presence of black carbon in liquid-water clouds. We show that the popular Maxwell-Garnett effective-medium approximation can be used to calculate the optical cross sections, single-scattering albedo, and asymmetry parameter for the quasi-uniform mixing scenario, but is likely to fail in application to other mixing scenarios and in computations of the elements of the scattering matrix.

  6. The nepheloid bottom layer and water masses at the shelf break of the western Ross Sea

    Science.gov (United States)

    Capello, Marco; Budillon, Giorgio; Cutroneo, Laura; Tucci, Sergio

    2009-06-01

    In the austral summers of 2000/2001 and 2002/2003 the Italian CLIMA Project carried out two oceanographic cruises along the northwestern margin of the Ross Sea, where the Antarctic Bottom Water forms. Here there is an interaction between the water masses on the sea floor of the outer shelf and slope with a consequent evolution of benthic nepheloid layers and an increase in total particulate matter. We observed three different situations: (a) the presence of triads (bottom structures characterized by a concomitant jump in turbidity, temperature, and salinity data) and high re-suspension phenomena related to the presence of the Circumpolar Deep Water and its mixing with cold, salty shelf waters associated with gravity currents; (b) the absence of triads with high re-suspension, implying that when the gravity currents are no longer active the benthic nepheloid layer may persist until the suspended particles settle to the sea floor, suggesting that the turbidity data can be used to study recent gravity current events; and (c) the absence of turbidity and sediment re-suspension phenomena supports the theory that a steady situation had been re-established and the current interaction no longer occurred or had finished sometime before.

  7. Modeling of condensation, stratification, and mixing phenomena in a pool of water

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.; Kudinov, P.; Villanueva, W. (Royal Institute of Technology (KTH). Div. of Nuclear Power Safety, Stockholm (Sweden))

    2010-12-15

    This work pertains to the research program on Containment Thermal-Hydraulics at KTH. The objective is to evaluate and improve performance of methods, which are used to analyze thermal-hydraulics of steam suppression pools in a BWR plant under different abnormal transient and accident conditions. As a passive safety system, the function of steam pressure suppression pools is paramount to the containment performance. In the present work, the focus is on apparently-benign but intricate and potentially risk-significant scenarios in which thermal stratification could significantly impede the pool's pressure suppression capacity. For the case of small flow rates of steam influx, the steam condenses rapidly in the pool and the hot condensate rises in a narrow plume above the steam injection plane and spreads into a thin layer at the pool's free surface. When the steam flow rate increases significantly, momentum introduced by the steam injection and/or periodic expansion and shrink of large steam bubbles due to direct contact condensation can cause breakdown of the stratified layers and lead to mixing of the pool water. Accurate prediction of the pool thermal-hydraulics in such scenarios presents a computational challenge. Lumped-parameter models have no capability to predict temperature distribution of water pool during thermal stratification development. While high-order-accurate CFD (RANS, LES) methods are not practical due to excessive computing power needed to calculate 3D high-Rayleighnumber natural circulation flow in long transients. In the present work, a middleground approach is used, namely CFD-like model of the general purpose thermalhydraulic code GOTHIC. Each cell of 3D GOTHIC grid uses lumped parameter volume type closures for modeling of various heat and mass transfer processes at subgrid scale. We use GOTHIC to simulate POOLEX/PPOOLEX experiment, in order to (a) quantify errors due to GOTHIC's physical models and numerical schemes, and (b

  8. On the deep water masses outflow in the Aegean Sea: a pre- and post-EMT analysis

    Science.gov (United States)

    Bellacicco, Marco; Falcini, Federico; Salusti, Ettore

    2017-04-01

    In the last decades, the Aegean Sea (AS) has drawn attention and interest from the oceanographic community about the role that this sea has played in the Eastern Mediterranean Transient (EMT), with the key result of a "new" deep-water formation site in the eastern Mediterranean basin. This deep-water formation was due to different reasons: i) water budget anomalies that increased salinity of the surface and intermediate water masses; ii) the enters of these waters in the AS from Eastern Mediterranean Sea thought the Cretan Straits, and iii) episodes of strong winter cooling. Here, we explore the importance of deep water masses outflow from Aegean Sea throughout the Cretan Sea into the oriental basin of the Mediterranean Sea, in relation to last recent studies, focusing on the EMT event and its time table. To such goal we use all available, in situ, hydrologic data collected in the period 1985-1999, by trying to describe the outflow of the deep-water masses in the Levantine basin. Preliminary results revealed that the main source of dense water was beween Samarcande and its northern coast while the entrance of dense water in the Cyclades Plateau was essentially a flow between the Islands of Euboea and Andros, confirming what found by Bellacicco et al. (2016) from numerical results and marine geological evidences. The new analysis, moreover, points out the presence of a dense water mass debouching in the Levantine from the Cretean Sea during the spring time (i.e., maximum mixing period)of 1986-1988.Our results may allow to open new research question on the actual EMT timing and triggering, also considering theoretical model analyses (Smith 1975, Bellacicco et al., 2016).

  9. The unique chemistry of Eastern Mediterranean water masses selects for distinct microbial communities by depth.

    Directory of Open Access Journals (Sweden)

    Stephen M Techtmann

    Full Text Available The waters of the Eastern Mediterranean are characterized by unique physical and chemical properties within separate water masses occupying different depths. Distinct water masses are present throughout the oceans, which drive thermohaline circulation. These water masses may contain specific microbial assemblages. The goal of this study was to examine the effect of physical and geological phenomena on the microbial community of the Eastern Mediterranean water column. Chemical measurements were combined with phospholipid fatty acid (PLFA analysis and high-throughput 16S rRNA sequencing to characterize the microbial community in the water column at five sites. We demonstrate that the chemistry and microbial community of the water column were stratified into three distinct water masses. The salinity and nutrient concentrations vary between these water masses. Nutrient concentrations increased with depth, and salinity was highest in the intermediate water mass. Our PLFA analysis indicated different lipid classes were abundant in each water mass, suggesting that distinct groups of microbes inhabit these water masses. 16S rRNA gene sequencing confirmed the presence of distinct microbial communities in each water mass. Taxa involved in autotrophic nitrogen cycling were enriched in the intermediate water mass suggesting that microbes in this water mass may be important to the nitrogen cycle of the Eastern Mediterranean. The Eastern Mediterranean also contains numerous active hydrocarbon seeps. We sampled above the North Alex Mud Volcano, in order to test the effect of these geological features on the microbial community in the adjacent water column. The community in the waters overlaying the mud volcano was distinct from other communities collected at similar depths and was enriched in known hydrocarbon degrading taxa. Our results demonstrate that physical phenomena such stratification as well as geological phenomena such as mud volcanoes strongly

  10. Constraint on Right-Handed Squark Mixings from B_s - B_sbar Mass Difference

    CERN Document Server

    Endo, M; Endo, Motoi; Mishima, Satoshi

    2006-01-01

    We point out that the right-handed squark mixings can sizably enhance SUSY contributions to Delta M_s by taking into account renormalization group effects via the CKM matrix. The recent result of Delta M_s from the D0 experiment at the Tevatron thus implies a strong constraint on the right-handed mixings.

  11. Experimental and Computational Studies of Turbulent Mass Transfer in a Mixing Channel

    DEFF Research Database (Denmark)

    Hjertager, Lene Kristin; Hjertager, Bjørn H.; Solberg, Tron

    2008-01-01

    Experiments are carried out for passive mixing in order to obtain local mean and turbulent velocities and concentrations. The mixing takes place in a square channel with two inlets separated by a block. A combined PIV/PLIF technique is used to obtain instantaneous velocity and concentration field...

  12. Experiments and CFD Modelling of Turbulent Mass Transfer in a Mixing Channel

    DEFF Research Database (Denmark)

    Hjertager Osenbroch, Lene Kristin; Hjertager, Bjørn H.; Solberg, Tron

    2006-01-01

    Experiments are carried out for passive mixing in order to obtain local mean and turbulent velocities and concentrations. The mixing takes place in a square channel with two inlets separated by a block. A combined PIV/PLIF technique is used to obtain instantaneous velocity and concentration field...

  13. Integration of water footprint accounting and costs for optimal pulp supply mix in paper industry

    DEFF Research Database (Denmark)

    Manzardo, Alessandro; Ren, Jingzheng; Piantella, Antonio

    2014-01-01

    studies have focused on these aspects, but there have been no previous reports on the integrated application of raw material water footprint accounting and costs in the definition of the optimal supply mix of chemical pulps from different countries. The current models that have been applied specifically...... that minimizes the water footprint accounting results and costs of chemical pulp, thereby facilitating the assessment of the water footprint by accounting for different chemical pulps purchased from various suppliers, with a focus on the efficiency of the production process. Water footprint accounting......Chemical pulp is one of the most important raw materials used in the paper industry. This material is known to make a significant contribution to the water footprint and cost of final paper products; therefore, chemical pulp is crucial in determining the competitiveness of final products'. Several...

  14. Mixing of water in a carbonate aquifer, southern Italy, analysed through stable isotope investigations

    Directory of Open Access Journals (Sweden)

    Petrella Emma

    2013-01-01

    Full Text Available Mixing of water was analysed in a carbonate aquifer, southern Italy, through stable isotope investigations (18O,δ2H. The input signal (rainwater was compared with the isotopic content of a 35-meter groundwater vertical prof ile, over a 1-year period. Within the studied aquifer, recharge and f low are diffuse in a well-connected f issure network.At the test site, the comparison between input and groundwater isotopic signals illustrates that no eff icient mixing takes place in the whole unsaturated zone, between the fresh inf iltration water and the stored water.When analysing the stable isotope composition of groundwater, signif icant variations were observed above the threshold elevation of 1062 m asl, while a nearly constant composition was observed below the same threshold. Thus, temporal variations in stable isotope composition of rainwater are completely attenuated just in the deeper phreatic zone.On the whole, taking into consideration also the results of previous studies in the same area, the investigations showed that physical characteristics of the carbonate bedrock, as well as aquifer heterogeneity, are factors of utmost importance in inf luencing the complete mixing of water. These f indings suggest a more complex scenario at catchment scale.

  15. Phase separated anionic domains in ternary mixed lipid monolayers at the air-water interface.

    Science.gov (United States)

    Maloney, K M; Grainger, D W

    1993-04-01

    A series of ternary mixed monolayers containing varying amounts of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and equimolar additions of 1-palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine (LYSO-PC) and palmitic acid (PA) were studied at the air-water interface. These mixed monolayers were used to model phospholipid biomembrane interfaces resulting from phospholipase A2 (PLA2) hydrolysis. Recent work [D.W. Grainger A. Reichert, H. Ringsdorf and C. Salesse (1989) Biochim. Biophys. Acta. 1023, 365-379] has shown that PLA2 hydrolysis of pure phospholipid monolayers results in formation of large PLA2 domains at the air-water interface. These domains are proposed to result from PLA2 adsorption to phase separated regions in the hydrolyzed monolayer. To elucidate the phase behaviour in these monolayer systems, surface pressure-area isotherms were measured for the ternary mixtures on pure water and buffered subphases. Fluorescence microscopy at the air-water interface was used to image fluorescent probe-doped monolayer mixtures during isothermal compressions. A water-soluble cationic carbocyanine dye was used to probe the interfacial properties of the mixed monolayers. Isotherm data do not provide unambiguous evidence for either phase separation or ideal mixing of monolayer components. Fluorescence microscopy is more revealing, showing that lateral phase separation of microstructures containing palmitic acid occurred only when monolayer subphases contained Ca2+ ions at alkaline pH. At either low pH or on Ca(2+)-free subphases, phase separation was not observed.

  16. A Fast GPU-accelerated Mixed-precision Strategy for Fully NonlinearWater Wave Computations

    DEFF Research Database (Denmark)

    Glimberg, Stefan Lemvig; Engsig-Karup, Allan Peter; Madsen, Morten G.

    2011-01-01

    We present performance results of a mixed-precision strategy developed to improve a recently developed massively parallel GPU-accelerated tool for fast and scalable simulation of unsteady fully nonlinear free surface water waves over uneven depths (Engsig-Karup et.al. 2011). The underlying wave...... model is based on a potential flow formulation, which requires efficient solution of a Laplace problem at large-scales. We report recent results on a new mixed-precision strategy for efficient iterative high-order accurate and scalable solution of the Laplace problem using a multigrid......-preconditioned defect correction method. The improved strategy improves the performance by exploiting architectural features of modern GPUs for mixed precision computations and is tested in a recently developed generic library for fast prototyping of PDE solvers. The new wave tool is applicable to solve and analyze...

  17. Determination of the external mass transfer coefficient and influence of mixing intensity in moving bed biofilm reactors for wastewater treatment.

    Science.gov (United States)

    Nogueira, Bruno L; Pérez, Julio; van Loosdrecht, Mark C M; Secchi, Argimiro R; Dezotti, Márcia; Biscaia, Evaristo C

    2015-09-01

    In moving bed biofilm reactors (MBBR), the removal of pollutants from wastewater is due to the substrate consumption by bacteria attached on suspended carriers. As a biofilm process, the substrates are transported from the bulk phase to the biofilm passing through a mass transfer resistance layer. This study proposes a methodology to determine the external mass transfer coefficient and identify the influence of the mixing intensity on the conversion process in-situ in MBBR systems. The method allows the determination of the external mass transfer coefficient in the reactor, which is a major advantage when compared to the previous methods that require mimicking hydrodynamics of the reactor in a flow chamber or in a separate vessel. The proposed methodology was evaluated in an aerobic lab-scale system operating with COD removal and nitrification. The impact of the mixing intensity on the conversion rates for ammonium and COD was tested individually. When comparing the effect of mixing intensity on the removal rates of COD and ammonium, a higher apparent external mass transfer resistance was found for ammonium. For the used aeration intensities, the external mass transfer coefficient for ammonium oxidation was ranging from 0.68 to 13.50 m d(-1) and for COD removal 2.9 to 22.4 m d(-1). The lower coefficient range for ammonium oxidation is likely related to the location of nitrifiers deeper in the biofilm. The measurement of external mass transfer rates in MBBR will help in better design and evaluation of MBBR system-based technologies.

  18. Technical Tools for Studying Structure and Dynamics of Water Masses

    Directory of Open Access Journals (Sweden)

    V.Z. Dykman

    2016-12-01

    Full Text Available The article gives a review of the technical tools designed to study structure and dynamics of water masses in the surface, bottom and deep-water sea layers, where the acting processes are not connected with wind waves. The process of adapting the measuring equipment to the requirements resulting from the expanding notions on physics of the marine environment phenomena is shown. Almost all the major designs are patented in the USSR, Ukraine and Russia. The experience in the development of different instruments enable adequately respond to the need for new methods and technical means intended for the organization of operational observations of the marine environment and land and sea interface zone. CTD-system experimental samples having a high degree of miniaturization and extremely low power consumption have already been created. They possess the necessary metrological characteristics and are intended for use in the drifters and lost (disposable probes. According to its metrological and operating characteristics, the autonomous electromagnetic current meter is able to provide reliable data in a variety of conditions (including collapse area of wind waves both being installed on a fixed base and hung on buoy stations. For wide manufacture of the new measurement tools it is necessary to create a complete set of design documentation on the basis of existing sketches, as well as to find the production base, equipped with machine tools of the corresponding class.

  19. An experimental study of hydromagmatic fragmentation through energetic, non-explosive magma-water mixing

    Science.gov (United States)

    Mastin, L.G.; Spieler, O.; Downey, W.S.

    2009-01-01

    In this paper we report the first experimental investigation of non-explosive hydromagmatic fragmentation during energetic mixing with water. We mix magma and water by two methods: (1) pouring a basaltic melt between two converging water sprays; and (2) jetting basaltic melt at high pressure (3??MPa) through a nozzle into a tank of stagnant water. These experiments involved shear at relative velocities of ~ 5-16??m/s and vigorous mixing for less than a second, providing sufficient time for glassy rinds to grow but insufficient time for clot interiors to cool. In resulting fragments, we examined the gross morphology, which reflects fluid deformation during mixing, and surface textures, which reflect the growth and disruption of glassy rinds. We find major differences in both fragment morphology and surface texture between experiments. Water-spray experiments produced Pele's hair, thin bubble shards, melt droplets, and angular, fracture-bound droplet pieces. Melt-jet experiments produced mostly coarse (> 1??mm diameter), wavy fluidal fragments with broken ends. Fluidal surfaces of fragments produced by water-spray experiments were generally shiny under reflected light and, in microscopic examination, smooth down to micron scale, implying no disruption of glassy rinds, except for (a) rare flaking on Pele's hair that was bent prior to solidification; or (b) cracking and alligator-skin textures on segments of melt balls that had expanded before complete cooling. In contrast, textures of fluidal surfaces on fragments produced by melt-jet experiments are dull in reflected light and, in scanning electron images, exhibit ubiquitous discontinuous skins ("rinds") that are flaked, peeled, or smeared away in stripes. Adhering to these surfaces are flakes, blocks, and blobs of detached material microns to tens of microns in diameter. In the water-spray fragments, we interpret the scarcity of disrupted surface rinds to result from lack of bending after surfaces formed. In the

  20. The valuation of water quality: Effects of mixing different drinking water qualities

    DEFF Research Database (Denmark)

    Rygaard, Martin; Arvin, Erik; Binning, Philip John

    2009-01-01

    impacts are cardiovascular diseases, dental caries, atopic eczema, lifetime of dish and clothes washing machines, heat exchangers, distribution systems, bottled water consumption and soap usage. The method includes an uncertainty assessment that ranks the imacts having the hi hest influence on the result......As water supplies increasingly turn to use desalination technologies it becomes relevant to consider the options for remineralization and blending with mineral rich water resources. We present a method for analyzing economic consequences due to changes in drinking water mineral content. Included...... and associated uncertainty. Effects are calculated for a scenario where 50% of Copenhagen's water supply is substituted by desalinated water. Without remineralization the total impact is expected to be negative ((sic) -0.44 +/- 0.2/m(3)) and individual impacts expected in the range of (sic)0.01-0.51/m(3...

  1. Measurements of mass flux and concentration in supersonic air/helium mixing by hot-wire anemometry

    OpenAIRE

    KONDO, Akira; Sakaue, Shoji; Arai, Takakage; 近藤 暁; 坂上 昇史; 新井 隆景

    2008-01-01

    In the present study we made efforts to realize a measurement method of mass flux and concentration in supersonic air/helium flow in order to clarify the mixing process. The measuring equipment, which was used for measuring the fluctuations of mass flux and concentration, is consisted of a double-hot-wire probe and CVA (Constant Voltage Anemometer) circuit with 500 kHz bandwidth. The distance between two wires of double-hot-wire probe was 0.16 mm. By using the same material as the hot wire, t...

  2. Spontaneous breaking of flavor symmetry and naturalness of nearly degenerate neutrino masses and bi-maximal mixing

    Institute of Scientific and Technical Information of China (English)

    吴岳良

    2000-01-01

    The gauge model with SO(3)F flavor symmetry and three Higgs triplets is studied. We show how the intriguing nearly degenerate neutrino mass and bi-maximal mixing scenario comes out naturally after spontaneous breaking of the symmetry. The hierarchy between the neutrino mass-squared differences, which is needed for reconciling both solar and atmospheric neutrino data, naturally results from an approximate permutation symmetry. The model can also lead to interesting phenomena on lepton-flavor violations via the SO(3)F gauge interactions.

  3. Mixing state of particles with secondary species by single particle aerosol mass spectrometer in an atmospheric pollution event

    Science.gov (United States)

    Xu, Lingling; Chen, Jinsheng

    2016-04-01

    Single particle aerosol mass spectrometer (SPAMS) was used to characterize size distribution, chemical composition, and mixing state of particles in an atmospheric pollution event during 20 Oct. - 5 Nov., 2015 in Xiamen, Southeast China. A total of 533,012 particle mass spectra were obtained and clustered into six groups, comprising of industry metal (4.5%), dust particles (2.6%), carbonaceous species (70.7%), K-Rich particles (20.7%), seasalt (0.6%) and other particles (0.9%). Carbonaceous species were further divided into EC (70.6%), OC (28.5%), and mixed ECOC (0.9%). There were 61.7%, 58.3%, 4.0%, and 14.6% of particles internally mixed with sulfate, nitrate, ammonium and C2H3O, respectively, indicating that these particles had undergone significant aging processing. Sulfate was preferentially mixed with carbonaceous particles, while nitrate tended to mix with metal-containing and dust particles. Compared to clear days, the fractions of EC-, metal- and dust particles remarkably increased, while the fraction of OC-containing particles decreased in pollution days. The mixing state of particles, excepted for OC-containing particles with secondary species was much stronger in pollution days than that in clear days, which revealed the significant influence of secondary particles in atmospheric pollution. The different activity of OC-containing particles might be related to their much smaller aerodynamic diameter. These results could improve our understanding of aerosol characteristics and could be helpful to further investigate the atmospheric process of particles.

  4. Responses of the circulation and water mass in the Beibu Gulf to the seasonal forcing regimes

    Institute of Scientific and Technical Information of China (English)

    GAO Jingsong; SHI Maochong; CHEN Bo; GUO Peifang; ZHAO Dongliang

    2014-01-01

    In the past 20 a, the gulf-scale circulation in the Beibu Gulf has been commonly accepted to be driven by a wind stress or density gradient. However, using three sensitive experiments based on a three-dimensional baroclinic model that was verified by observations, the formation mechanisms were revealed:the circula-tion in the northern Beibu Gulf was triggered by the monsoon wind throughout a year;whereas the southern gulf circulation was driven by the monsoon wind and South China Sea (SCS) circulation in winter and sum-mer, respectively. The force of heat flux and tidal harmonics had a strong effect on the circulation strength and range, as well as the local circulation structures, but these factors did not influence the major circulation structure in the Beibu Gulf. On the other hand, the Beibu Gulf Cold Water Mass (BGCWM) would disappear without the force of heat flux because the seasonal thermocline layer was generated by the input of heat so that the vertical mixing between the upper hot water and lower cold water was blocked. In addition, the wind-induced cyclonic gyre in the northern gulf was favorable to the existence of the BGCWM. However, the coverage area of the BGCWM was increased slightly without the force of the tidal harmonics. When the model was driven by the monthly averaged surface forcing, the circulation structure was changed to some extent, and the coverage area of the BGCWM almost extended outwards 100%, implying the circulation and water mass in the Beibu Gulf had strong responses to the temporal resolution of the surface forces.

  5. Understanding Structure, Metal Distribution, and Water Adsorption in Mixed-Metal MOF-74

    Energy Technology Data Exchange (ETDEWEB)

    Howe, Joshua D.; Morelock, Cody R.; Jiao, Yang; Chapman, Karena W.; Walton, Krista S.; Sholl, David S.

    2017-01-30

    We present a joint computational and experimental study of Mg–Ni-MOF-74 and Mg–Cd-MOF-74 to gain insight into the mixing of metals and understand how metal mixing affects the structure of the undercoordinated open-metal sites. Our calcula tions predict that metal mixing is energetically preferred in these materials. Recent experimental work has demonstrated that Mg–Ni-MOF-74 shows a much greater surface area retention in the presence of water than Mg-MOF-74. To probe this effect, we study H2O adsorption in Mg–Ni-MOF-74, finding that the adsorption en ergetics and electronic structure do not change significantly at the metal sites when compared to Mg-MOF-74 and Ni-MOF-74, respectively. We conclude that the in creased stability of Mg–Ni-MOF-74 is a result of a M–O bond length distortion in mixed-metal MOF-74, consistent with recent work on the stability of MOF-74 under water exposure.

  6. B0-B0bar mixing in the static approximation from the Schroedinger Functional and twisted mass QCD

    OpenAIRE

    Palombi, F.; Papinutto, M.; Pena., C; Wittig, H.

    2005-01-01

    We discuss the renormalisation properties of parity-odd Delta B=2 operators with the heavy quark treated in the static approximation. Via twisted mass QCD (tmQCD), these operators provide the matrix elements relevant for the B0-B0bar mixing amplitude. The layout of a non-perturbative renormalisation programme for the operator basis, using Schroedinger Functional techniques, is described. Finally, we report our results for a one-loop perturbative study of various renormalisation schemes with W...

  7. Experimental and Computational Studies of Turbulent Mass Transfer in a Mixing Channel

    DEFF Research Database (Denmark)

    Hjertager, Lene Kristin; Hjertager, Bjørn H.; Solberg, Tron

    2008-01-01

    Experiments are carried out for passive mixing in order to obtain local mean and turbulent velocities and concentrations. The mixing takes place in a square channel with two inlets separated by a block. A combined PIV/PLIF technique is used to obtain instantaneous velocity and concentration fields....... Three different flow cases are studied. The 2D numerical predictions of the mixing channel show that none of the k- ε turbulence models tested is suitable for the flow cases studied here. The turbulent Schmidt number is reduced to obtain a better agreement between measured and predicted mean...

  8. Applying rotary jet heads for mixing and mass transfer in a forced recirculation tank reactor system

    DEFF Research Database (Denmark)

    Nordkvist, Mikkel; Grotkjær, Thomas; Hummer, J.S.

    2003-01-01

    An approximation to an ideally mixed tank reactor can be obtained by vigorous stirring with mechanical mixers. For an aerated reactor the gas dispersion contributes to the mixing process. Mixing can also be achieved by recirculation of a portion of the liquid through either an internal...... at 1-9 bar gauge pressure into the bulk liquid. Liquid feed can be added to the bulk volume or it may be injected into the pressurized recirculation loop. Gas is always fed to the recirculation loop, and the heat of reaction is removed in a plate-type heat exchanger inserted in the recirculation loop...

  9. Use of a mixing model to investigate groundwater-surface water mixing and nitrogen biogeochemistry in the bed of a groundwater-fed river

    Science.gov (United States)

    Lansdown, Katrina; Heppell, Kate; Ullah, Sami; Heathwaite, A. Louise; Trimmer, Mark; Binley, Andrew; Heaton, Tim; Zhang, Hao

    2010-05-01

    The dynamics of groundwater and surface water mixing and associated nitrogen transformations in the hyporheic zone have been investigated within a gaining reach of a groundwater-fed river (River Leith, Cumbria, UK). The regional aquifer consists of Permo-Triassic sandstone, which is overlain by varying depths of glaciofluvial sediments (~15 to 50 cm) to form the river bed. The reach investigated (~250m long) consists of a series of riffle and pool sequences (Käser et al. 2009), with other geomorphic features such as vegetated islands and marginal bars also present. A network of 17 piezometers, each with six depth-distributed pore water samplers based on the design of Rivett et al. (2008), was installed in the river bed in June 2009. An additional 18 piezometers with a single pore water sampler were installed in the riparian zone along the study reach. Water samples were collected from the pore water samplers on three occasions during summer 2009, a period of low flow. The zone of groundwater-surface water mixing within the river bed sediments was inferred from depth profiles (0 to 100 cm) of conservative chemical species and isotopes of water with the collected samples. Sediment cores collected during piezometer installation also enabled characterisation of grain size within the hyporheic zone. A multi-component mixing model was developed to quantify the relative contributions of different water sources (surface water, groundwater and bank exfiltration) to the hyporheic zone. Depth profiles of ‘predicted' nitrate concentration were constructed using the relative contribution of each water source to the hyporheic and the nitrate concentration of the end members. This approach assumes that the mixing of different sources of water is the only factor controlling the nitrate concentration of pore water in the river bed sediments. Comparison of predicted nitrate concentrations (which assume only mixing of waters with different nitrate concentrations) with actual

  10. NUMERICAL STUDY ON THE STABILITY AND MIXING OF VERTICAL ROUNE BUOYANT JET IN SHALLOW WATER

    Institute of Scientific and Technical Information of China (English)

    曾玉红; 槐文信

    2005-01-01

    The k-epsilon model was applied to establish the mathematical model of vertical round buoyant jet discharging into confined depth, and it was solved using the Hybrid Finite Analytic Method ( HFAM ). The numerical predictions demonstrate two generic flow patterns for different jet discharge and environmental parameters: ( i ) a stable buoyant flow discharge with the mixed fluid leaving the near-field warm in a surface warm water layer;( ii ) an unstable buoyant flow discharge with recirculation and re-entrainment of warm water in the near field. Furthermore, the mixing characters of vertical round buoyant jet were numerically predicted. Both the stability criterion and numerical predictions of bulk dilutions are in excellent agreement with Lee and Jirka ' s experiments and theory.

  11. A mathematical model for unsteady mixed flows in closed water pipes

    Institute of Scientific and Technical Information of China (English)

    BOURDARIAS; Christian; ERSOY; Mehmet; GERBI; Stéphane

    2012-01-01

    We present the formal derivation of a new unidirectional model for unsteady mixed flows in nonuniform closed water pipes.In the case of free surface incompressible flows,the FS-model is formally obtained,using formal asymptotic analysis,which is an extension to more classical shallow water models.In the same way,when the pipe is full,we propose the P-model,which describes the evolution of a compressible inviscid flow,close to gas dynamics equations in a nozzle.In order to cope with the transition between a free surface state and a pressured(i.e.,compressible) state,we propose a mixed model,the PFS-model,taking into account changes of section and slope variation.

  12. A mathematical model for unsteady mixed flows in closed water pipes

    CERN Document Server

    Bourdarias, Christian; Gerbi, Stéphane

    2011-01-01

    We present the formal derivation of a new unidirectional model for unsteady mixed flows in non uniform closed water pipe. In the case of free surface incompressible flows, the \\FS-model is formally obtained, using formal asymptotic analysis, which is an extension to more classical shallow water models. In the same way, when the pipe is full, we propose the \\Pres-model, which describes the evolution of a compressible inviscid flow, close to gas dynamics equations in a nozzle. In order to cope the transition between a free surface state and a pressured (i.e. compressible) state, we propose a mixed model, the \\PFS-model, taking into account changes of section and slope variation.

  13. Unsteady mixed flows in non uniform closed water pipes: a Full Kinetic Appraoch

    CERN Document Server

    Bourdarias, Christian; Gerbi, Stéphane

    2011-01-01

    We recall the \\PFS} model constructed for the modeling of unsteady mixed flows in closed water pipes where transition points between the free surface and pressurized flow are treated as a free boundary associated to a discontinuity of the gradient of pressure. Then we present a numerical kinetic scheme for the computations of unsteady mixed flows in closed water pipes. This kinetic method that we call FKA for "Full Kinetic Approach" is an easy and mathematically elegant way to deal with multiple transition points when the changes of state between free surface and pressurized flow occur. We use two approaches namely the "ghost waves approach" and the "Full Kinetic Approach" to treat these transition points. We show that this kinetic numerical scheme has the following properties: it is wet area conservative, under a CFL condition it preserves the wet area positive, it treats "naturally" the drying and flooding area and most of all it preserves every stationary flow. Finally numerical experiment versus laborator...

  14. The Mixed Mechanism in the Management of Water Resources in China

    Institute of Scientific and Technical Information of China (English)

    Chen Ming

    2005-01-01

    It is a challenge for China to address its serious water resource problems, and inefficient water use. Improving water use efficiency is the key solution to dealing with this issue. There are two basic mechanisms practiced in the world aiming to pursue water conservation, i.e. administrative and market-based management pattern. Water as an irreplaceable resource with many attributes, either public or market-based management mechanism has its disadvantages. In order to avoid the inherent "administrative failure" or "market failure", this paper emphasizes the importance of changing traditional water resource management mechanism to establish a mixed mechanism of public and market water management based on China's conditions and experiences from developed countries. Three key aspects of this combined mechanism are identified in this paper, i.e. recognizing and managing water rights to promote efficiency, strengthening effectiveness of government management to lower transaction cost and encouraging water user participation to increase flexibility. Detailed information on implementing of this combined mechanism in China is given in the end.

  15. Polybenzimidazole-based mixed membranes with exceptional high water vapor permeability and selectivity

    KAUST Repository

    Akhtar, Faheem Hassan

    2017-09-13

    Polybenzimidazole (PBI), a thermal and chemically stable polymer, is commonly used to fabricate membranes for applications like hydrogen recovery at temperatures of more than 300 °C, fuel cells working in a highly acidic environment, and nanofiltration in aggressive solvents. This report shows for the first time use of PBI dense membranes for water vapor/gas separation applications. They showed an excellent selectivity and high water vapor permeability. Incorporation of inorganic hydrophilic titanium-based nano-fillers into the PBI matrix further increased the water vapor permeability and water vapor/N2 selectivity. The most selective mixed matrix membrane with 0.5 wt% loading of TiO2 nanotubes yielded a water vapor permeability of 6.8×104 Barrer and a H2O/N2 selectivity of 3.9×106. The most permeable membrane with 1 wt% loading of carboxylated TiO2 nanoparticles had a 7.1×104 Barrer water vapor permeability and a H2O/N2 selectivity of 3.1×106. The performance of these membranes in terms of water vapor transport and selectivity is among the highest reported ones. The remarkable ability of PBI to efficiently permeate water versus other gases opens the possibility to fabricate membranes for dehumidification of streams in harsh environments. This includes the removal of water from high temperature reaction mixtures to shift the equilibrium towards products.

  16. Mesoscale variability of water masses in the Arabian Sea as revealed by ARGO floats

    Directory of Open Access Journals (Sweden)

    X. Carton

    2012-03-01

    Full Text Available By analysing ARGO float data over the last four years, a few aspects of the mesoscale variability of water masses in the Arabian Sea are described.

    The Red Sea Outflow Water (RSOW is concentrated in the Southwestern Gulf of Aden, in particular when a cyclonic gyre predominates in this region. Salinities of 36.5 and temperatures of 16 °C are found in this area at depths between 600 and 1000 m. RSOW is more dilute in the eastern part of the Gulf, where intense and relatively barotropic gyres mix it with Indian ocean Central Water. RSOW is also detected along the northeastern coast of Socotra, and fragments of RSOW are found between one and three degrees of latitude north of this island. In the whole Gulf of Aden, the correlation between the deep motions of the floats and the sea-level anomaly measured by altimetry is strong, at regional scale. The finer scale details of the float trajectories are not sampled by altimetry and are often related to the anomalous water masses that the floats encounter.

    The Persian Gulf Water (PGW is found in the float profiles near Ras ash Sharbatat (near 57° E, 18° N, again with 36.5 in salinity and about 18–19 °C in temperature. These observations were achieved in winter when the southwestward monsoon currents can advect PGW along the South Arabian coast. Fragments of PGW were also observed in the Arabian Sea between 18 and 20° N and 63 and 65° E in summer, showing that this water mass can escape the Gulf of Oman southeastward, during that season.

    Kinetic energy distributions of floats with respect to distance or angle share common features between the two regions (Gulf of Aden and Arabian Sea, in particular peaks at 30, 50 and 150 km scales and along the axis of monsoon currents. Hydrological measurements by floats are also influenced by the seasonal variations of PGW and RSOW in these regions.

  17. [Chemicohydrographic characteristics and the seasonal variations of nutrients at 35 degrees N transect in the cold water mass of the Southern Yellow Sea].

    Science.gov (United States)

    Wei, Qin-Sheng; Fu, Ming-Zhu; Ge, Ren-Feng; Zang, Jia-Ye

    2010-09-01

    Based on the four cruises during 2006-2007, the chemicohydrographic characteristics and the seasonal variations of nutrients at 35 degrees N transect in the cold water mass of the Southern Yellow Sea were analyzed. The results showed that: In Winter, hydrological conditions in the eastern part of the section was significantly influenced by the Yellow Sea Warm Current, and the vertical mixing in the deep water had not reached the bottom, which led to the different distribution of the elements in the eastern and western part of the section, the vertically uniform distribution was presented in the west and the upper water of the east, while the stratification structure was found in the bottom water of the east. In Spring, the Yellow Sea warm current residual water and the Qingdao cold water mass were the most obviously hydrological characteristics, and because of the increasing of the temperature in the upper water and the weakening of the vertical mixing, the stability of the water column increased gradually; compared with winter, the contour trend of DO, pH and nutrients in deep water transferred to the more horizontal direction, and with the arrival of spring blooming, the nutrient concentrations in the upper water decreased significantly, besides, the subsurface chlorophyll maximum (SCM) phenomena also began to emerge. In Summer, the section was influenced by the thermocline and the Yellow Sea cold water mass, which was accompanied with the maximum value phenomenon of DO and pH, in addition, the nutrient concentrations were low in upper water and high in bottom water, and compared with spring, the further reduction of the nutrient concentrations existed in upper water, but the nutrient concentrations were increasing dominantly in the water below the thermocline. In Autumn, with the decreasing of the temperature in the upper water and the enhancing of the vertical mixing, the stability of the water column decreased, but the vertical mixing in the deep water was

  18. Monetite formed in mixed solvents of water and ethylene glycol and its transformation to hydroxyapatite.

    Science.gov (United States)

    Ma, Ming-Guo; Zhu, Ying-Jie; Chang, Jiang

    2006-07-27

    Agglomerated nanorods of hydroxyapatite have been synthesized using monetite as a precursor in a NaOH solution. Monetite consisting of nanosheets has been successfully synthesized by a one-step microwave-assisted method using CaCl(2).2.5H(2)O, NaH(2)PO(4), and sodium dodecyl sulfate (SDS) in water/ethylene glycol (EG) mixed solvents. The effects of the molar ratio of water to EG and the reaction time on the products were investigated. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectrometry (FTIR).

  19. STABILITY AND MIXING CHARACTER FOR BUOYANT JETS IN QUIESCENT SHALLOW WATER

    Institute of Scientific and Technical Information of China (English)

    ZENG Yu-hong

    2005-01-01

    The near field stability and mixing characteristics of buoyant jets produced by thermal diffuse in quiescent shallow water are investigated numerically to predict under what combinations of discharge and ambient characteristics the near field will be stable or unstable.Analyses for different discharging types show that the discharge stability is purely dependent on the near-field behavior of the jets, or the dynamic interaction of the buoyant jet region, the surface impingement region and the internal hydraulic jump region, and is independent of the far-field geometry of the receiving water.The stability criterion is a function of the relative submerged depth, and source densimetric Froude number.

  20. Enhancement of nitrate removal at the sediment-water interface by carbon addition plus vertical mixing.

    Science.gov (United States)

    Chen, Xuechu; He, Shengbing; Zhang, Yueping; Huang, Xiaobo; Huang, Yingying; Chen, Danyue; Huang, Xiaochen; Tang, Jianwu

    2015-10-01

    Wetlands and ponds are frequently used to remove nitrate from effluents or runoffs. However, the efficiency of this approach is limited. Based on the assumption that introducing vertical mixing to water column plus carbon addition would benefit the diffusion across the sediment-water interface, we conducted simulation experiments to identify a method for enhancing nitrate removal. The results suggested that the sediment-water interface has a great potential for nitrate removal, and the potential can be activated after several days of acclimation. Adding additional carbon plus mixing significantly increases the nitrate removal capacity, and the removal of total nitrogen (TN) and nitrate-nitrogen (NO3(-)-N) is well fitted to a first-order reaction model. Adding Hydrilla verticillata debris as a carbon source increased nitrate removal, whereas adding Eichhornia crassipe decreased it. Adding ethanol plus mixing greatly improved the removal performance, with the removal rate of NO3(-)-N and TN reaching 15.0-16.5 g m(-2) d(-1). The feasibility of this enhancement method was further confirmed with a wetland microcosm, and the NO3(-)-N removal rate maintained at 10.0-12.0 g m(-2) d(-1) at a hydraulic loading rate of 0.5 m d(-1).

  1. Distribution of intermediate water masses in the subtropical northeast Atlantic

    Directory of Open Access Journals (Sweden)

    I. Bashmachnikov

    2015-05-01

    Full Text Available This work presents the quantitative study of climatological distributions of mid-depth Source Water Types in the NE Atlantic by the Optimum Multiparameter analysis (OMP, merging a~number of regional results from particular synoptic sections. The cores of the Mediterranean Water (MW, the modified Antarctic Intermediate Water (mAAIW and the Subarctic Intermediate Water (SAIW are detected and spatial variations of their depth/density are obtained: as expected, spreading of the source water types is predominantly isopycnic and follows the major mid-depth circulation patterns. In some areas the turbulent transport should also be considered. The MW in the Atlantic spreads as 3 cores of different density: the upper MW core (northwest of the first transition line between 28° W, 35° N and 14° W, 44° N is found in the neutral density range of 27.65–27.70 kg m−3 and depths of 900–1000 m; the main MW core (northwest of the second transition line between 35° W, 28° N and 10° W, 37° N has neutral density around 27.75 kg m−3 and is found at 1000–1100 m; the lower MW core (southeast of the second transition has neutral density around 27.80 kg m−3 and is found at 1250–1350 m. The upper MW core has comparatively low MW contents (below 30% and is speculated to be transported by the mean flow from the northern Iberian Peninsula and the Bay of Biscay to the northern Azores. The main MW core contains the most of the MW. It primarily originates from the MUC between Cape St. Vincent and Estremadura Promontory, where the strongest local decrease of the topographic β-effect is detected and is transported west by a flow at around 39° N. The lower MW core originates in the Gulf of Cadiz and is translated southwestwards by dominating flows. The SAIW (the core between 27.70 and 27.75 kg m−3 is found to spread south along both slopes of the MAR. The SAIW east of the MAR mixes with the upper and the main MW cores and re-circulates in a cyclonic gyre

  2. Modeling surface and ground water mixing in the hyporheic zone using MODFLOW and MT3D

    Science.gov (United States)

    Lautz, Laura K.; Siegel, Donald I.

    2006-11-01

    We used a three-dimensional MODFLOW model, paired with MT3D, to simulate hyporheic zones around debris dams and meanders along a semi-arid stream. MT3D simulates both advective transport and sink/source mixing of solutes, in contrast to particle tracking (e.g. MODPATH), which only considers advection. We delineated the hydrochemically active hyporheic zone based on a new definition, specifically as near-stream subsurface zones receiving a minimum of 10% surface water within a 10-day travel time. Modeling results indicate that movement of surface water into the hyporheic zone is predominantly an advective process. We show that debris dams are a key driver of surface water into the subsurface along the experimental reach, causing the largest flux rates of water across the streambed and creating hyporheic zones with up to twice the cross-sectional area of other hyporheic zones. Hyporheic exchange was also found in highly sinuous segments of the experimental reach, but flux rates are lower and the cross-sectional areas of these zones are generally smaller. Our modeling approach simulated surface and ground water mixing in the hyporheic zone, and thus provides numerical approximations that are more comparable to field-based observations of surface-groundwater exchange than standard particle-tracking simulations.

  3. Potential of mixed microalgae to harness biodiesel from ecological water-bodies with simultaneous treatment.

    Science.gov (United States)

    Mohan, S Venkata; Devi, M Prathima; Mohanakrishna, G; Amarnath, N; Babu, M Lenin; Sarma, P N

    2011-01-01

    Biodiesel as an eco-friendly fuel is gaining much acceptance in recent years. This communication provides an overview on the possibility of using mixed microalgae existing in ecological water-bodies for harnessing biodiesel. Microalgal cultures from five water-bodies are cultivated in domestic wastewater in open-ponds and the harvested algal-biomass was processed through acid-catalyzed transesterification. Experiments evidenced the potential of using mixed microalgae for harnessing biodiesel. Presence of palmitic acid (C16:0) in higher fraction and physical properties of algal oil correlated well with the biodiesel properties. Functional characteristics of water-bodies showed to influence both species diversity and lipid accumulation. Microalgae from stagnant water-bodies receiving domestic discharges documented higher lipid accumulation. Algal-oil showed to consist 33 types of saturated and unsaturated fatty acids having wide food and fuel characteristics. Simultaneous wastewater treatment was also noticed due to the syntrophic association in the water-body microenvironment. Diversity studies visualized the composition of algae species known to accumulate higher lipids.

  4. Algal growth and community structure in a mixed-culture system using coal seam gas water as the water source.

    Science.gov (United States)

    Buchanan, Jessica J; Slater, Frances R; Bai, Xue; Pratt, Steven

    2013-01-01

    Coal seam gas (CSG) is being touted as a transition fuel as the world moves towards low-carbon economies. However, the development of CSG reserves will generate enormous volumes of saline water. In this work, we investigate the potential of using this saline water to support mass algae production. Water and brine from a CSG water treatment facility (1.6 and 11.6 g total dissolved solids per litre (TDS L(-1)) respectively) were inoculated with algal biomass from freshwater and seawater environments and supplemented with nutrients in open, fed-batch reactors. Significant algal growth was recorded, with maximum specific growth rates in CSG water and CSG brine of 0.20 +/- 0.05 d(-1) and 0.26 +/- 0.04 d(-1) respectively. These maximum specific growth rates were equal to or greater than specific growth rates in deionized water and seawater diluted to the same salinity. However, algal growth lag time in CSG brine was between 7 and 9 times longer than in other waters. Microscopy and terminal-restriction fragment length polymorphism (T-RFLP) were used to monitor community structure in the reactors. The same few algal species dominated all of the reactors, except for the CSG brine reactor at day 15. This result indicates that conditions in CSG brine select for different species of algae compared to seawater of the same salinity and other waters tested. The findings suggest that mass algae production in CSG water is feasible but algae community composition may be a function of CSG water chemistry. This has implications for the downstream use of algae.

  5. Mass-based hygroscopicity parameter interaction model and measurement of atmospheric aerosol water uptake

    Directory of Open Access Journals (Sweden)

    E. Mikhailov

    2013-01-01

    Full Text Available In this study we derive and apply a mass-based hygroscopicity parameter interaction model for efficient description of concentration-dependent water uptake by atmospheric aerosol particles with complex chemical composition. The model approach builds on the single hygroscopicity parameter model of Petters and Kreidenweis (2007. We introduce an observable mass-based hygroscopicity parameter κm which can be deconvoluted into a dilute hygroscopicity parameter (κm0 and additional self- and cross-interaction parameters describing non-ideal solution behavior and concentration dependencies of single- and multi-component systems.

    For reference aerosol samples of sodium chloride and ammonium sulfate, the κm-interaction model (KIM captures the experimentally observed concentration and humidity dependence of the hygroscopicity parameter and is in good agreement with an accurate reference model based on the Pitzer ion-interaction approach (Aerosol Inorganic Model, AIM. Experimental results for pure organic particles (malonic acid, levoglucosan and for mixed organic-inorganic particles (malonic acid – ammonium sulfate are also well reproduced by KIM, taking into account apparent or equilibrium solubilities for stepwise or gradual deliquescence and efflorescence transitions.

    The mixed organic-inorganic particles as well as atmospheric aerosol samples exhibit three distinctly different regimes of hygroscopicity: (I a quasi-eutonic deliquescence & efflorescence regime at low-humidity where substances are just partly dissolved and exist also in a non-dissolved phase, (II a gradual deliquescence & efflorescence regime at intermediate humidity where different solutes undergo gradual dissolution or solidification in the aqueous phase; and (III a dilute regime at high humidity where the solutes are fully dissolved approaching their dilute hygroscopicity.

    For atmospheric aerosol samples

  6. Southwest Atlantic water mass evolution during the last deglaciation

    Science.gov (United States)

    Lund, D. C.; Tessin, A. C.; Hoffman, J. L.; Schmittner, A.

    2015-05-01

    The rise in atmospheric CO2 during Heinrich Stadial 1 (HS1; 14.5-17.5 kyr B.P.) may have been driven by the release of carbon from the abyssal ocean. Model simulations suggest that wind-driven upwelling in the Southern Ocean can liberate 13C-depleted carbon from the abyss, causing atmospheric CO2 to increase and the δ13C of CO2 to decrease. One prediction of the Southern Ocean hypothesis is that water mass tracers in the deep South Atlantic should register a circulation response early in the deglaciation. Here we test this idea using a depth transect of 12 cores from the Brazil Margin. We show that records below 2300 m remained 13C-depleted until 15 kyr B.P. or later, indicating that the abyssal South Atlantic was an unlikely source of light carbon to the atmosphere during HS1. Benthic δ18O results are consistent with abyssal South Atlantic isolation until 15 kyr B.P., in contrast to shallower sites. The depth dependent timing of the δ18O signal suggests that correcting δ18O for ice volume is problematic on glacial terminations. New data from 2700 to 3000 m show that the deep SW Atlantic was isotopically distinct from the abyss during HS1. As a result, we find that mid-depth δ13C minima were most likely driven by an abrupt drop in δ13C of northern component water. Low δ13C at the Brazil Margin also coincided with an ~80‰ decrease in Δ14C. Our results are consistent with a weakening of the Atlantic meridional overturning circulation and point toward a northern hemisphere trigger for the initial rise in atmospheric CO2 during HS1.

  7. Dispersive Mixing? Mass Transfer? Microbial Dynamics? Potential Controls of Bioreactive Transport

    Science.gov (United States)

    Cirpka, O. A.; Loschko, M.; Eckert, D.; Mellage, A.

    2016-12-01

    Mixing-controlled reactive transport, in which compounds A and B must come together to react, has gained significant attention in the past years. The goal is to formulate upscaled, effective equations of reactive transport in physically and chemically heterogeneous media without fully resolving the heterogeneity. Towards this end, it is important to analyze which processes control the overall reactive behavior. The presentation classifies potential controls of (bio)reactive transport into several categories, for which different effective transport equations may be derived. The replacement scenario (solution of B replaces the solution of A) has become a popular target to study fundamental aspects of dispersive mixing. In most cases, it s assumed that neither A nor B sorb. Under such conditions, the reaction is controlled by macroscopic longitudinal dispersive mixing, which is controlled by variability of velocity and micro-scale transverse mixing. However, in most practical applications, at least one of the two compounds sorbs. If A sorbs more strongly than B, chromatographic mixing will always dominate over dispersive mixing at late times. A second popular scenario is a continuously released plume of A, reacting with B provided by ambient flow. This system is controlled by macroscopic transverse dispersion, which increases much less than longitudinal mixing in heterogeneous domains. Transient flow leads to some additional enhancement, but not very much. If the compounds sorb differently, transient flow causes alternating chromatographic mixing and separation. Many contaminants react with the aquifer matrix. In these cases, dispersive mixing is merely a nuisance, and the controling factor is the release of the reaction partner from the matrix. Here, travel-time based approaches work if chemical heterogeneity can be excluded. To account for the latter, one can integrate the time of exposure to reactive materials, eventually scaled by the intensity of the reaction, to

  8. Numerical investigation of cavitation-vortex interaction in a mixed-flow water jet pump

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Renfang; Lou, Xianwu [Tsinghua University, Beijing (China); Ji, Bin [Wuhan University, Hubei (China); Zhai, Zhihong; Zhou, Jiajian [Marine Design and Research Institute of China, Shanghai (China)

    2015-09-15

    Turbulent cavitating flows in a mixed-flow waterjet pump were numerically investigated using the k-w SST turbulence model and the mass transfer cavitation model based on the Rayleigh-Plesset equation to provide a comprehensive understanding of the cavitation-vortex interaction mechanism. The predicted hydraulic performance, as well as the cavitation performance, exhibits a reasonable agreement with the experimental results. The vorticity distributions under three operation conditions were illustrated together. Based on the illustration, cavitation development enhances vorticity production and flow unsteadiness in a mixed-flow waterjet pump. Vortices are basically located at the cavity interface, particularly at the downstream interface, during cavitation. Further analyses using the relative vorticity transport equation in cavitating turbulent flows indicate that vortex dilation and baroclinic torque exhibit a steep jump as cavitation occurs. In addition, vortex stretching contributes mainly to large-scale vortex generation.

  9. Operational simulation of continental water masses consistent with atmospheric and oceanic data.

    OpenAIRE

    Robert Dill; Walter, C.;  

    2008-01-01

    Operational global mass transport data of the atmosphere and the oceans are widely used for studies of earth rotation excitation and gravity field simulations and are essential for GRACE dealising purposes, too. Seasonal and short periodic variations are also caused by continental water mass redistributions. In order to account for the continental hydrology processes as well and to close the global water cycle, continental water mass storage fields and fluxes are needed in the same operationa...

  10. Veterinary pharmaceutical contamination in mixed land use watersheds: from agricultural headwater to water monitoring watershed.

    Science.gov (United States)

    Jaffrézic, A; Jardé, E; Soulier, A; Carrera, L; Marengue, E; Cailleau, A; Le Bot, B

    2017-12-31

    Veterinary pharmaceuticals, widely used in intensive livestock production, may contaminate surface waters. Identifying their sources and pathways in watersheds is difficult because i) most veterinary pharmaceuticals are used in human medicine as well and ii) septic or sewer wastewater treatment plants (WWTP) can release pharmaceuticals into surface water, even in agricultural headwater watersheds. This study aimed to analyze the spatiotemporal variability of animal-specific, mixed-use, and human-specific pharmaceuticals, from agricultural headwaters with intensive livestock production and a WWTP to a watershed used for Water Framework Directive monitoring. Grab sampling was performed during one hydrological year upstream and downstream from a WWTP and at three dates in seven nested watersheds with areas of 1.9-84.1km(2). Twenty pharmaceuticals were analyzed. Animal-specific pharmaceuticals were detected at all sampling dates upstream and downstream from the WWTP and at concentrations higher than those of human-specific pharmaceuticals. The predominance of animal-specific and mixed-use pharmaceuticals vs. human-specific pharmaceuticals observed at these sampling points was confirmed at the other sampling points. Animal-specific pharmaceuticals were detected mainly during runoff events and periods of manure spreading. A large percentage of mixed-use pharmaceuticals could come from animal sources, but it was difficult to determine. Mixed-use and human-specific pharmaceuticals predominated in the largest watersheds when runoff decreased. In areas of intensive livestock production, mitigation actions should focus on agricultural headwater watersheds to decrease the number of pathways and the transfer volume of veterinary pharmaceuticals, which can be the main contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The hydromedusae and water masses of the Indian Ocean

    Directory of Open Access Journals (Sweden)

    D. Navas-Pereira

    1991-01-01

    Full Text Available This analysis of distribution and abundance of species of Hydromedusae completes a report (Vannucci & Navas, 1973b on the ecology of Indian Ocean Hydromedusae based on the zooplankton collected during the International Indian Ocean Expedition (IIOE. Distribution and abundance are taken here to be the ecological expression of variability of species in space and time. The aim was to identify the biological signature of below surface water masses that cannot be identified by remote sensing techniques. Selected species were taken as biological units, the oceanic water masses as defined by their T-S and T-O2 diagrammes were taken as the non biological units. Taken together they define different ecosystems of the Indian Ocean. About 45,000 specimens of hydromedusae taken at 480 stations were sorted from 900 plankton samples and all specimens were determined and counted. Several hauls, mostly stratified, were taken with closing nets, but not all contained hydromedusae. The distribution of each species was studied in relation to water salinity, temperature and dissolved oxygen; the limits of ecological tolerance and preference were defined by the environmental characteristics of the layers sampled by the nets and are given for each species. These can be grouped as follows: 1. Deep water species, cold tolerant, often eurytopic; 2. Antarctic species, cold loving, usually stenothermal with preference for low salinity; 3. Indian Ocean Central Water species, with preference for temperature lower than 19ºC and salinity not much higher than 35%o, usually found at sub-surface or intermediate depths, they may spread into the Arabian Sea and Bay of Bengal in surface layers; 4. Indian Ocean Equatorial System species, warm tolerant, usually prefer comparatively low salinity, high temperature and high oxygen content; 5. Bay of Bengal Surface Water species, found in surface layers of the Bay, with preference for low salinity, high temperature and high oxygen content

  12. A realistic pattern of lepton mixing and masses from S4 and CP

    DEFF Research Database (Denmark)

    Feruglio, Ferruccio; Hagedorn, Claudia; Ziegler, Robert

    2014-01-01

    We present a supersymmetric model with the flavour symmetry S4 × Z3 and a CP symmetry which are broken to a Z3 subgroup of the flavour symmetry in the charged lepton sector and to Z2×CP (×Z3) in the neutrino one at leading order. This model implements an approach capable of predicting lepton mixing...... angles and Dirac as well as Majorana phases in terms of one free parameter. This parameter, directly related to the size of the reactor mixing angle θ13, can be naturally of the correct order in our model. Atmospheric mixing is maximal, while sin2 θ12 ≳ 1/3. All three phases are predicted: the Dirac...

  13. Inward Radial Mixing of Interstellar Water Ices in the Solar Protoplanetary Disk

    Science.gov (United States)

    Vacher, Lionel G.; Marrocchi, Yves; Verdier-Paoletti, Maximilien J.; Villeneuve, Johan; Gounelle, Matthieu

    2016-08-01

    The very wide diversity of asteroid compositions in the main belt suggests significant material transport in the solar protoplanetary disk and hints at the presence of interstellar ices in hydrated bodies. However, only a few quantitative estimations of the contribution of interstellar ice in the inner solar system have been reported, leading to considerable uncertainty about the extent of radial inward mixing in the solar protoplanetary disk 4.56 Ga ago. We show that the pristine CM chondrite Paris contains primary Ca-carbonates whose O-isotopic compositions require an 8%–35% contribution from interstellar water. The presence of interstellar water in Paris is confirmed by its bulk D/H isotopic composition that shows significant D enrichment (D/H = (167 ± 0.2) × 10‑6) relative to the mean D/H of CM chondrites ((145 ± 3) × 10‑6) and the putative D/H of local CM water ((82 ± 1.5) × 10‑6). These results imply that (i) efficient radial mixing of interstellar ices occurred from the outer zone of the solar protoplanetary disk inward and that (ii) chondrites accreted water ice grains from increasing heliocentric distances in the solar protoplanetary disk.

  14. Effect of $^{12}C+$ $^{12}C$ Reaction & Convective Mixing on the Progenitor Mass of ONe White Dwarfs

    CERN Document Server

    Halabi, Ghina M

    2014-01-01

    Stars in the mass range ~8 - 12 $M_{\\odot }$ are the most numerous massive stars. This mass range is critical because it may lead to supernova (SN) explosion, so it is important for the production of heavy elements and the chemical evolution of the galaxy. We investigate the critical transition mass ($M_{up}$), which is the minimum initial stellar mass that attains the conditions for hydrostatic carbon burning. Stars of masses < $M_{up}$ evolve to the Asymptotic Giant Branch and then develop CO White Dwarfs, while stars of masses $\\geqslant $ $M_{up}$ ignite carbon in a partially degenerate CO core and form electron degenerate ONe cores. These stars evolve to the Super AGB (SAGB) phase and either become progenitors of ONe White Dwarfs or eventually explode as electron-capture SN (EC-SN). We study the sensitivity of $M_{up}$ to the C-burning reaction rate and to the treatment of convective mixing. In particular, we show the effect of a recent determination of the $^{12}C+$ $^{12}C$ fusion rate, as well as t...

  15. Angular momentum redistribution by mixed modes in evolved low-mass stars. II. Spin-down of the core of red giants induced by mixed modes

    CERN Document Server

    Belkacem, K; Goupil, M J; Mosser, B; Sonoi, T; Ouazzani, R M; Dupret, M A; Mathis, S; Grosjean, M

    2015-01-01

    The detection of mixed modes in subgiants and red giants by the CoRoT and \\emph{Kepler} space-borne missions allows us to investigate the internal structure of evolved low-mass stars. In particular, the measurement of the mean core rotation rate as a function of the evolution places stringent constraints on the physical mechanisms responsible for the angular momentum redistribution in stars. It showed that the current stellar evolution codes including the modelling of rotation fail to reproduce the observations. An additional physical process that efficiently extracts angular momentum from the core is thus necessary. Our aim is to assess the ability of mixed modes to do this. To this end, we developed a formalism that provides a modelling of the wave fluxes in both the mean angular momentum and the mean energy equations in a companion paper. In this article, mode amplitudes are modelled based on recent asteroseismic observations, and a quantitative estimate of the angular momentum transfer is obtained. This i...

  16. Evaluation of mixing and mass transfer in a stirred pilot scale bioreactor utilizing CFD

    DEFF Research Database (Denmark)

    Bach, Christian; Yang, Jifeng; Larsson, Hilde Kristina

    2017-01-01

    transfer coefficients were determined from six Trichoderma reesei fermentations at different well-defined process conditions. Similarly the mass transfer was predicted by Higbie’s penetration model from two-phase CFD simulations using a correlation of bubble size and power input, and the overall mass...

  17. Masses and mixing matrices of quarks within the spin-charge-family theory

    CERN Document Server

    Bregar, Gregor

    2012-01-01

    The spin-charge-family theory predicts the number of families. There are four massless families of quarks and leptons before the electroweak break. There are two kinds of charges in this theory, connected with two kinds of the Clifford objects. The Dirac like kind explains the spin and the standard model charges, the second kind explains the existence of families. Correspondingly there are two kinds of scalar fields, determining masses of vector bosons and mass matrices of fermions. The first kind distinguishes only among family members, the second kind only among families. Mass matrices exhibit correspondingly very particular symmetries. In this contribution we take matrix elements as free parameters, which we determine by requiring that mass matrices keep by the spin-charge-family theory determined symmetries and that properties of fermions agree with the experimental data. Very preliminary results show that matrix elements of one of the two quark mass matrices are surprisingly close (within a factor of les...

  18. Application of environmental tracers to mixing, evolution, and nitrate contamination of ground water in Jeju Island, Korea

    Science.gov (United States)

    Koh, D.-C.; Niel, Plummer L.; Kip, Solomon D.; Busenberg, E.; Kim, Y.-J.; Chang, H.-W.

    2006-01-01

    Tritium/helium-3 (3H/3He) and chlorofluorocarbons (CFCs) were investigated as environmental tracers in ground water from Jeju Island (Republic of Korea), a basaltic volcanic island. Ground-water mixing was evaluated by comparing 3H and CFC-12 concentrations with lumped-parameter dispersion models, which distinguished old water recharged before the 1950s with negligible 3H and CFC-12 from younger water. Low 3H levels in a considerable number of samples cannot be explained by the mixing models, and were interpreted as binary mixing of old and younger water; a process also identified in alkalinity and pH of ground water. The ground-water CFC-12 age is much older in water from wells completed in confined zones of the hydro-volcanic Seogwipo Formation in coastal areas than in water from the basaltic aquifer. Major cation concentrations are much higher in young water with high nitrate than those in uncontaminated old water. Chemical evolution of ground water resulting from silicate weathering in basaltic rocks reaches the zeolite-smectite phase boundary. The calcite saturation state of ground water increases with the CFC-12 apparent (piston flow) age. In agricultural areas, the temporal trend of nitrate concentration in ground water is consistent with the known history of chemical fertilizer use on the island, but increase of nitrate concentration in ground water is more abrupt after the late 1970s compared with the exponential growth of nitrogen inputs. ?? 2005 Elsevier B.V. All rights reserved.

  19. Water Droplet Impingement on Simulated Glaze, Mixed, and Rime Ice Accretions

    Science.gov (United States)

    Papadakis, Michael; Rachman, Arief; Wong, See-Cheuk; Yeong, Hsiung-Wei; Hung, Kuohsing E.; Vu, Giao T.; Bidwell, Colin S.

    2007-01-01

    Water droplet impingement data were obtained at the NASA Glenn Icing Research Tunnel (IRT) for a 36-in. chord NACA 23012 airfoil with and without simulated ice using a dye-tracer method. The simulated ice shapes were defined with the NASA Glenn LEWICE 2.2 ice accretion program and including one rime, four mixed and five glaze ice shapes. The impingement experiments were performed with spray clouds having median volumetric diameters of 20, 52, 111, 154, and 236 micron. Comparisons to the experimental data were generated which showed good agreement for the rime and mixed shapes at lower drop sizes. For larger drops sizes LEWICE 2.2 over predicted the collection efficiencies due to droplet splashing effects which were not modeled in the program. Also for the more complex glaze ice shapes interpolation errors resulted in the over prediction of collection efficiencies in cove or shadow regions of ice shapes.

  20. A Novel Ion Exchange System to Purify Mixed ISS Waste Water Brines for Chemical Production and Enhanced Water Recovery

    Science.gov (United States)

    Lunn, Griffin; Spencer, LaShelle; Ruby, Anna-Maria; McCaskill, Andrew

    2014-01-01

    Current International Space Station water recovery regimes produce a sizable portion of waste water brine. This brine is highly toxic and water recovery is poor: a highly wasteful proposition. With new biological techniques that do not require waste water chemical pretreatment, the resulting brine would be chromium-free and nitrate rich which can allow possible fertilizer recovery for future plant systems. Using a system of ion exchange resins we can remove hardness, sulfate, phosphate and nitrate from these brines to leave only sodium and potassium chloride. At this point modern chlor-alkali cells can be utilized to produce a low salt stream as well as an acid and base stream. The first stream can be used to gain higher water recovery through recycle to the water separation stage while the last two streams can be used to regenerate the ion exchange beds used here, as well as other ion exchange beds in the ISS. Conveniently these waste products from ion exchange regeneration would be suitable as plant fertilizer. In this report we go over the performance of state of the art resins designed for high selectivity of target ions under brine conditions. Using ersatz ISS waste water we can evaluate the performance of specific resins and calculate mass balances to determine resin effectiveness and process viability. If this system is feasible then we will be one step closer to closed loop environmental control and life support systems (ECLSS) for current or future applications.

  1. Mixing regime of the residual water basins of the Aral Sea

    Science.gov (United States)

    Izhitskiy, Alexander; Zavialov, Peter; Kirillin, Georgiy

    2017-04-01

    The Aral Sea, a terminal salt lake in western Central Asia situated at the border between Uzbekistan and Kazakhstan, was ranked as the fourth largest inland water body in the mid-20th century. However, in the early 1960s, the lake's volume started to decrease rapidly due to severe changes in the Aral's water balance. Thus, the present-day Aral Sea can be considered as a system of separate water bodies with a common origin but very different physical, chemical and biological features. Our previous studies showed that the Large Aral Sea and Lake Tshchebas transformed into hyperhaline water bodies, while the Small Aral Sea was a brackish basin with rather similar to the pre-desiccation environment. On the other hand, the Small Aral Sea and Lake Tshchebas exhibited a mixed vertical structure, whereas the Western Large Aral Sea (especially the Chernyshev Bay) was strongly stratified. The presented study is focused on the seasonal mixing regimes of the residual basins. Isolation of deep waters from the atmosphere together with low rates of photosynthesis produce deep anoxia observed in the Chernyshev Bay and in the Large Aral. The high amount of organic matter provides a rich source of nutrients for anoxic microorganisms favoring methanogenesis in the bottom layer of the basins. In the Small Aral, the water column remains well-oxygenated down to the bottom throughout most of the year and development of anoxia is unlikely. The mixing regimes of the recently formed residual lakes of the former Aral Sea will provide manifold effect on the ongoing development of the aquatic system in the following decades. The study is based on a field data collected during two surveys of Shirshov Institute of Oceanology to the Aral Sea, which took place in October, 2015 and June, 2016. In situ measurements including CTD profiling and water sampling were carried out in the northern extremity of the western Large Aral (the Chernyshev Bay), in Lake Tshchebas, and in the Small Aral Sea

  2. $T_7$ flavor symmetry scheme for understanding neutrino mass and mixing in 3-3-1 model with neutral leptons

    CERN Document Server

    Vien, V V

    2015-01-01

    We construct a new version for the 3-3-1 model based on $T_7$ flavor symmetry where the left-handed leptons under $T_7$ differ from those of our previous work while the $\\mathrm{SU}(3)_C \\otimes \\mathrm{SU}(3)_L \\otimes \\mathrm{U}(1)_X$ gauge symmetry is retain. The flavor mixing patterns and mass splitting are obtained without perturbation. The realistic lepton mixing can be obtained if both the direction of breakings $T_7 \\rightarrow Z_3$ and $Z_3 \\rightarrow \\{\\mathrm{Identity}\\}$ are taken place in neutrino sector. Maximal CP violation is predicted and CKM matrix is the identity matrix at the tree-level.

  3. Water masses in Kangerlussuaq, a large fjord in West Greenland: the processes of formation and the associated foraminiferal fauna

    DEFF Research Database (Denmark)

    Nielsen, Morten Holtegaard; Erbs-Hansen, Dorthe Reng; Knudsen, Karen Luise

    2010-01-01

    The water masses in Kangerlussuaq (Søndre Strømfjord) in West Greenland were studied during both a summer and a winter field survey. In order to obtain an improved understanding of the relationship between the physical oceanography and modern foraminiferal assemblage distributions, conductivity...... dissolution. A monospecific, calcareous assemblage (Elphidium excavatum forma clavata) occurs in the innermost, shallow part, which is strongly influenced by sediment-loaded meltwater during the summer. The outer, shallow part of the fjord is dominated by strong tidal mixing, and in summer the density...

  4. Toxicity of Water and Sediment Samples Collected in the Vicinity of the Mixed Waste Management Facility, 1995 and 1996

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1996-07-01

    Three rounds of toxicity tests were conducted on water collected from eleven locations in the vicinity of the Mixed Waste Management Facility and four reference locations between January 1995 and April 1996.

  5. Bovine insulin-phosphatidylcholine mixed Langmuir monolayers: behavior at the air-water interface.

    Science.gov (United States)

    Pérez-López, S; Blanco-Vila, N M; Vila-Romeu, N

    2011-08-04

    The behavior of the binary mixed Langmuir monolayers of bovine insulin (INS) and phosphatidylcholine (PC) spread at the air-water interface was investigated under various subphase conditions. Pure and mixed monolayers were spread on water, on NaOH and phosphate-buffered solutions of pH 7.4, and on Zn(2+)-containing solutions. Miscibility and interactions between the components were studied on the basis of the analysis of the surface pressure (π)-mean molecular area (A) isotherms, surface compression modulus (C(s)(-1))-π curves, and plots of A versus mole fraction of INS (X(INS)). Our results indicate that intermolecular interactions between INS and PC depend on both the monolayer state and the structural characteristics of INS at the interface, which are strongly influenced by the subphase pH and salt content. Brewster angle microscopy (BAM) was applied to investigate the peptide aggregation pattern at the air-water interface in the presence of the studied lipid under any experimental condition investigated. The influence of the lipid on the INS behavior at the interface strongly depends on the subphase conditions.

  6. Mixed-layer water oscillations in tropical Pacific for ENSO cycle

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The main modes of interannal variabilities of thermocline and sea surface wind stress in the tropical Pacific and their interactions are investigated, which show the following results. (1) The thermocline anomalies in the tropical Pacific have a zonal dipole pattern with 160°W as its axis and a meridional seesaw pattern with 6-8°N as its transverse axis. The meridional oscillation has a phase lag of about 90° to the zonal oscillation, both oscillations get together to form the El Ni(n)o/La Ni(n)a cycle, which behaves as a mixed layer water oscillates anticlockwise within the tropical Pacific basin between equator and 12°N. (2) There are two main patterns of wind stress anomalies in the tropical Pacific, of which the first component caused by trade wind anomaly is characterized by the zonal wind stress anomalies and its corresponding divergences field in the equatorial Pacific, and the abnormal cross-equatorial flow wind stress and its corresponding divergence field, which has a sign opposite to that of the equatorial region, in the off-equator of the tropical North Pacific, and the second component represents the wind stress anomalies and corresponding divergences caused by the ITCZ anomaly. (3) The trade winds anomaly plays a decisive role in the strength and phase transition of the ENSO cycle, which results in the sea level tilting, provides an initial potential energy to the mixed layer water oscillation, and causes the opposite thermocline displacement between the west side and east side of the equator and also between the equator and 12°N of the North Pacific basin, therefore determines the amplitude and route for ENSO cycle. The ITCZ anomaly has some effects on the phase transition. (4) The thermal anomaly of the tropical western Pacific causes the wind stress anomaly and extends eastward along the equator accompanied with the mixed layer water oscillation in the equatorial Pacific, which causes the trade winds anomaly and produces the anomalous wind

  7. Analysis of seasonal variation of water masses in East China Sea

    Science.gov (United States)

    Qi, Jifeng; Yin, Baoshu; Zhang, Qilong; Yang, Dezhou; Xu, Zhenhua

    2014-07-01

    Seasonal variations of water masses in the East China Sea (ECS) and adjacent areas are investigated, based on historical data of temperature and salinity ( T-S). Dynamic and thermodynamic mechanisms that affect seasonal variations of some dominant water masses are discussed, with reference to meteorological data. In the ECS above depth 600 m, there are eight water masses in summer but only five in winter. Among these, Kuroshio Surface Water (KSW), Kuroshio Intermediate Water (KIW), ECS Surface Water (ECSSW), Continental Coastal Water (CCW), and Yellow Sea Surface Water (YSSW) exist throughout the year. Kuroshio Subsurface Water (KSSW), ECS Deep Water (ECSDW), and Yellow Sea Bottom Water (YSBW) are all seasonal water masses, occurring from May through October. The CCW, ECSSW and KSW all have significant seasonal variations, both in their horizontal and vertical extents and their T-S properties. Wind stress, the Kuroshio and its branch currents, and coastal currents are dynamic factors for seasonal variation in spatial extent of the CCW, KSW, and ECSSW, whereas sea surface heat and freshwater fluxes are thermodynamic factors for seasonal variations of T-S properties and thickness of these water masses. In addition, the CCW is affected by river runoff and ECSSW by the CCW and KSW.

  8. High-Resolution Electrospray Ionization Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle into Liquid Sampler

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

    2010-10-01

    This work demonstrates the utility of a particle-into-liquid sampler (PILS) a technique traditionally used for identification of inorganic ions present in ambient or laboratory aerosols for the analysis of water soluble organic aerosol (OA) using high resolution electrospray ionization mass spectrometry (HR ESI-MS). Secondary organic aerosol (SOA) was produced from 0.5 ppm mixing ratios of limonene and ozone in a 5 m3 Teflon chamber. SOA was collected simultaneously using a traditional filter sampler and a PILS. The filter samples were later extracted with either water or acetonitrile, while the aqueous PILS samples were analyzed directly. In terms of peak intensities, types of detectable compounds, average O:C ratios, and organic mass to organic carbon ratios, the resulting high resolution mass spectra were essentially identical for the PILS and filter based samples. SOA compounds extracted from both filter/acetonitrile extraction and PILS/water extraction accounted for >95% of the total ion current in ESI mass spectra. This similarity was attributed to high solubility of limonene SOA in water. In contrast, significant differences in detected ions and peak abundances were observed for pine needle biomass burning organic aerosol (BBOA) collected with PILS and filter sampling. The water soluble fraction of BBOA is considerably smaller than for SOA, and a number of unique peaks were detectable only by the filter/acetonitrile method. The combination of PILS collection with HR-ESI-MS analysis offers a new approach for molecular analysis of the water-soluble organic fraction in biogenic SOA, aged photochemical smog, and BBOA.

  9. B0 - anti-B0 mixing in the static approximation from the Schrodinger functional and twisted mass QCD

    CERN Document Server

    Palombi, Filippo; Peña, C; Wittig, H

    2005-01-01

    We discuss the renormalisation properties of parity-odd Delta B=2 operators with the heavy quark treated in the static approximation. Via twisted mass QCD (tmQCD), these operators provide the matrix elements relevant for the B0-B0bar mixing amplitude. The layout of a non-perturbative renormalisation programme for the operator basis, using Schroedinger Functional techniques, is described. Finally, we report our results for a one-loop perturbative study of various renormalisation schemes with Wilson-type lattice regularisations, which allows, in particular, to compute the NLO anomalous dimensions of the operators in the SF schemes of interest.

  10. Mixed convection effects on heat and mass transfer in a non Newtonian fluid with chemical reaction over a vertical plate

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper studies mixed convection,double dispersion and chemical reaction effects on heat and mass transfer in a non-Darcy non-Newtonian fluid over a vertical surface in a porous medium under the constant temperature and concentration.The governing boundary layer equations,namely,momentum,energy and concentration,are converted to ordinary differential equations by introducing similarity variables and then are solved numerically by means of fourth-order Runge-Kutta method coupled with double-shooting techn...

  11. A clinoptilolite-PDMS mixed-matrix membrane for high temperature water softening.

    Science.gov (United States)

    Yazdanbakhsh, Farzad; Alizadehgiashi, Moien; Sawada, James A; Kuznicki, Steven M

    2016-01-01

    A mixed-matrix membrane composed of polydimethylsiloxane (PDMS) as the continuous phase and clinoptilolite, a naturally occurring zeolite, as the active phase has been used to decrease the conductivity of water by more than 80% across the membrane. Testing was carried out using a cross-flow configuration at temperatures as high as 160 °C using a constant transmembrane pressure of 8 bar. The simple fabrication method for the membrane, the durability of the system under the test conditions, and a suitable flux rate make such membranes promising candidates for industrial wastewater treatment.

  12. Influence of the addition sequence of PVA-fibers and water on mixing and rheological behavior of mortars

    Directory of Open Access Journals (Sweden)

    M. S. de França

    Full Text Available ABSTRACT The mixing process of fiber-containing cementitious suspensions is a crucial factor to obtaining a good dispersion of fibers and guarantee adequate mechanical performance of the hardened products. The addition of fibers into the suspension causes reduction of the fluidity of the system due to factors inherent to the fibers, the matrix and their interaction. During mixing, these interactions make dispersion and homogenization processes more difficult due to the formation of fibers - particles agglomerates. Conventional techniques to assess workability of mortars are inadequate to evaluate the rheological behavior of fiber-reinforced systems, in which parameters like viscosity and yield stress are not completely taken into account. Therefore, this work employs rotational rheometry to evaluate the influence of fiber and water addition sequences on mixing and rheological behavior of mortars containing Polyvinyl Alcohol (PVA fibers. Constant test parameters were: mixing time of 317s; impeller velocity 126.5 rpm; water flow 128g/s. A constant mix design was used with a water content of 16%wt, and a 0.2%vol of fibers were added to the reference composition. Four mixing sequences were studied: S1 and S2 are based on the addition of fibers at different stages of the mixing process; while in S3 and S4 not only the fibers are added at different stages, but also the water addition is performed in two steps (25% first and 75% latter.Results showed that it is possible to optimize the mixing step of fiber-containing systems by changing the moment of fiber addition into the mixture. The introduction of fibers after mixing the dry mortar with water, when it already had achieved its fluidity point, demanded a lower mixing effort and produced a more flowable material.

  13. Soil water storage, mixing dynamics and resulting travel times through the critical zone in northern latitudes

    Science.gov (United States)

    Sprenger, Matthias; Tetzlaff, Doerthe; Weiler, Markus; Soulsby, Chris

    2017-04-01

    Water partitioning in the unsaturated zone into groundwater recharge, plant transpiration, and evaporation is fundamental for estimating storages and travel times. How water is mixed and routed through the soil is of broad interest to understand plant available water, contamination transport and weathering rates in the critical zone. Earlier work has shown how seasonal changes in hydroclimate influence the time variant character of travel times. A strong seasonality characterizes the northern latitudes which are particularly sensitive to climate and land use changes. It is crucial to understand how variation and change in hydroclimate and vegetation phenology impact time variant storage dynamics and flow path partitioning in the unsaturated zone. To better understand the influence of these ecohydrological processes on travel times of evaporative, transpiration and recharge fluxes in northern latitudes, we characterized soil physical properties, hydrometric conditions and soil water isotopic composition in the upper soil profile in two different land scape units in the long term experimental catchment, Bruntland Burn in the Scottish Highlands. Our two sampling locations are characterized by podzol soils with high organic matter content but they differ with regard to their vegetation cover with either Scots Pine (Pinus sylvestris) or heather (Calluna sp. and Erica Sp). To assess storage and mixing dynamics in the vadose zone, we parameterized a numerical 1-D flow model using the soil textural information along with soil moisture and soil water stable isotopes (δ2H and δ18O). The water flow and transport were simulated based on the Richards and the advection dispersion equation. Differences between water flows of mobile and tightly bound soil waters and the mixing between the two pore spaces were considered. Isotopic fractionation due to evaporation from soil and interception storage was taken into account, while plant water uptake did not alter the isotopic

  14. Black sea annual and inter-annual water mass variations from space

    DEFF Research Database (Denmark)

    Yildiz, H.; Andersen, Ole Baltazar; Simav, M.;

    2011-01-01

    This study evaluates the performance of two widely used GRACE solutions (CNES/GRGS RL02 and CSR RL04) in deriving annual and inter-annual water mass variations in the Black Sea for the period 2003–2007. It is demonstrated that the GRACE derived water mass variations in the Black Sea are heavily i...

  15. 33 CFR 334.70 - Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations.

    Science.gov (United States)

    2010-07-01

    ..., Mass.; danger zones for naval operations. 334.70 Section 334.70 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.70 Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations. (a)...

  16. Mixed gas water vapor/N2 transport in poly(ethylene oxide) poly(butylene terephthalate) block copolymers

    NARCIS (Netherlands)

    Metz, S.J.; van de Ven, W.J.C.; Mulder, M.H.V.; Wessling, Matthias

    2005-01-01

    This paper studies the mass transport properties for water vapor and nitrogen for a series of poly(ethylene oxide) (PEO) poly(butylene terephthalate) (PBT) multi-block copolymers via: (a) the permeation of a water vapor/N2 mixture (b) the sorption of water vapor, (c) the diffusion of water vapor, (d

  17. Features of mixing micellar muds with oil and water in their influence on efficiency of oil displacement

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Y.; Lu, G.

    1982-01-01

    An experimental study was made of the process of mixing micellar muds (MM) and different composition with oil and water (a total of 150 samples), and also the influence of this mixing on the efficient displacement of oil with the use of MM to increase oil output. It has been indicated that the process of mixing MM with oil and water can be examined as a process of diffusion. It is described by the second law of Fick. In this case the coefficient of diffusion depends on the concentration of salt in water: with an increase in concentration of salt in water, the coefficient of diffusion of MM in water is diminished, and in oil increases. In addition, the coefficient of diffusion depends on the viscosity of MM, and is higher if the initial concentration of the diffused substance is high. It was found that in the process of mixing MM with oil in water, emulsification of dilution and selected emulsification and MM of different compositions can be divided into four types: does not emulsify in oil and water; does not emulsify in oil, but emulsifies in water; emulsifies in oil but does not emulsify in water, and emulsifies in oil and water. It was established that of the aforementioned four types of MM, type one has the highest effective displacement of oil. Injection initially of MM of type two, and then type 3 results in even higher efficiency of oil displacement.

  18. MiRTE: Mixed Reality Triage and Evacuation game for Mass Casualty information systems design, testing and training.

    Science.gov (United States)

    Yu, Xunyi; Ganz, Aura

    2011-01-01

    In this paper we introduce a Mixed Reality Triage and Evacuation game, MiRTE, that is used in the development, testing and training of Mass Casualty Incident (MCI) information systems for first responders. Using the Source game engine from Valve software, MiRTE creates immersive virtual environments to simulate various incident scenarios, and enables interactions between multiple players/first responders. What distinguishes it from a pure computer simulation game is that it can interface with external mass casualty incident management systems, such as DIORAMA. The game will enable system developers to specify technical requirements of underlying technology, and test different alternatives of design. After the information system hardware and software are completed, the game can simulate various algorithms such as localization technologies, and interface with an actual user interface on PCs and Smartphones. We implemented and tested the game with the DIORAMA system.

  19. Mobile lidar system for measurement of water vapor mixing ratio and ozone number density

    Science.gov (United States)

    Whiteman, D.

    1988-01-01

    The Water Vapor Lidar was modified and extended to make differential absorption measurements of ozone. Water vapor measurements make use of a weak molecular scattering process known as Raman scattering. It is characterized by a shift in wavelength of the scattered beam of light relative to the incident one. Some of the energy of the incident photon is converted to vibrational or rotational energy within the molecule leaving the scattered photon shifted to a slightly longer wavelength. When performing water vapor measurements, profiles are acquired of water vapor mixing ratio from near the ground to beyond 7 km every 2 minutes. By forming a color composite image of the individual profiles, the spatial and temporal evolution of water vapor is visible with vertical resolution of 75 to 150m and temporal resolution of 2 minutes. The ozone lidar is intended for use as a cross calibration facility for other stationary ozone lidar systems. The ozone measurement employs the technique known as differential absorption. The backscattered laser radiation from two different wavelengths is measured. Successful measurements of 308 nm returns were made from 80 km with an averaging period of 6 hours. Using these data and a standard atmosphere density curve, an ozone number density profile was made which agrees very well with the standard ozone curve between 20 and 40 km.

  20. Radium isotopes assess water mixing processes and its application in the Zhujiang River estuary

    Science.gov (United States)

    Guo, Xiaoyi; Xu, Bochao; Yu, Zhigang; Li, Xiuqin; Nan, Haiming; Jian, Huimin; Jiang, Xueyan; Diao, Shaobo; Gao, Maosheng

    2017-09-01

    Radium (Ra) isotopes are useful for tracing water mass transport and examining estuarine hydrological dynamics. In this study, several hydrological parameters, nutrients, chlorophyll- a (chl- a), suspended particulate matter (SPM) and Ra isotopes (223Ra, 224Ra and 226Ra) of surface waters of the Zhujiang (Pearl) River estuary (ZRE) were measured. This was done for both winter (December) and summer (July) seasons, to quantitatively understand the seasonal characteristics of river plume flow rate and trajectories, as well as the ecological response. The results show that Ra concentrations in summer were higher than in winter, especially 224Ra (about 2-5 times higher). The spatial distribution of three Ra isotopes and relative Ra water ages indicated that river water mainly flushed out of ZRE through the western side in winter, where the water transport was about 5 days faster than in the eastern zone. In summer, diluted river water expended to the east side, resulting in fairly similar water ages for both sides of the river mouth. Although nutrients were higher during the summer season, lower chl- a concentrations indicated that reduced primary production might be caused by high SPM (low light penetration). The results obtained from this study will provide knowledge needed for effectively developing and managing the ZRE.

  1. Synthesis of nanoiron by microemulsion with Span/Tween as mixed surfactants for reduction of nitrate in water

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yunxia; LI Tielong; JIN Zhaohui; WANG Wei; WANG Shuaima

    2007-01-01

    Denitrification of nitrate in groundwater using iron nanoparticles has received increasing interest in recent years.In order to fabricate iron nanoparticles with homogeneously spherical shape and narrow size distribution,a simple and"green"method was developed to synthesize iron nanoparticles.The conventional microemulsion methods were modified by applying Span 80 and Tween 60 as mixed surfactants.The maximum content of water in the Water-in-oil(W/O) microemulsion and its appropriate forming conditions were found,and then the microemulsion system consisting of saturated Fe2+ solution was used to synthesize α-Fe ultrafine particles by redox reaction.The nanoparticles were characterized by using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM).The results show that the average diameter of the particle is about 80-90 nm.The chemical activity of the obtained iron nanoparticles was studied by the denitrification experiment of nitrate.The results show that under the experimental conditions,iron removed most of the 80 mg/L nitrate within 30 min.The mass balance of nitrate reduction with nanoscale Fe indicates that endproducts are mainly ammonia.Two possible reaction pathways for nitrate reduction by nanoscale iron particles have been proposed in this work.

  2. Point processes statistics of stable isotopes: analysing water uptake patterns in a mixed stand of Aleppo pine and Holm oak

    OpenAIRE

    Carles Comas; Jorge del Castillo,; Jordi Voltas; Juan Pedro Ferrio

    2015-01-01

    Aim of study: Understanding inter- and intra-specific competition for water is crucial in drought-prone environments. However, little is known about the spatial interdependencies for water uptake among individuals in mixed stands. The aim of this work was to compare water uptake patterns during a drought episode in two common Mediterranean tree species, Quercus ilex L. and Pinus halepensis Mill., using the isotope composition of xylem water (δ18O, δ2 H) as hydrological marker. ...

  3. Identifying water mass depletion in Northern Iraq observed by GRACE

    Directory of Open Access Journals (Sweden)

    G. Mulder

    2014-10-01

    Full Text Available Observations acquired by Gravity Recovery And Climate Experiment (GRACE mission indicate a mass loss of 31 ± 3 km3 or 130 ± 14 mm in Northern Iraq between 2007 and 2009. This data is used as an independent validation of a hydrologic model of the region including lake mass variations. We developed a rainfall–runoff model for five tributaries of the Tigris River, based on local geology and climate conditions. Model inputs are precipitation from Tropical Rainfall Measurement Mission (TRMM observations, and potential evaporation from GLDAS model parameters. Our model includes a representation of the karstified aquifers that cause large natural groundwater variations in this region. Observed river discharges were used to calibrate our model. In order to get the total mass variations, we corrected for lake mass variations derived from Moderate Resolution Imaging Spectroradiometer (MODIS in combination with satellite altimetry and some in-situ data. Our rainfall–runoff model confirms that Northern Iraq suffered a drought between 2007 and 2009 and is consistent with the mass loss observed by GRACE over that period. Also, GRACE observed the annual cycle predicted by the rainfall–runoff model. The total mass depletion seen by GRACE between 2007 and 2009 is mainly explained by a lake mass depletion of 74 ± 4 mm and a natural groundwater depletion of 37 ± 6 mm. Our findings indicate that man-made groundwater extraction has a minor influence in this region while depletion of lake mass and geology play a key role.

  4. Vector-like fields, messenger mixing and the Higgs mass in gauge mediation

    Energy Technology Data Exchange (ETDEWEB)

    Fischler, Willy; Tangarife, Walter [Department of Physics and Texas Cosmology Center,The University of Texas at Austin,TX 78712 (United States)

    2014-05-30

    In order to generate, in the context of gauge mediation, a Higgs mass around 126 GeV that avoids the little hierarchy problem, we explore a set of models where the messengers are directly coupled to new vector-like fields at the TeV scale in addition to the usual low energy degrees of freedom. We find that in this context, stop masses lighter than 2 TeV and large A-terms are generated, thereby improving issues of fine tuning.

  5. Neutrino masses and mixing parameters in a left-right model with mirror fermions

    CERN Document Server

    Gaitan, R; Rivera-Rebolledo, J M; de C'ordoba, P F

    2006-01-01

    In this work we consider a left-right model containing mirror fermions with gauge group SU(3)$_{C} \\otimes SU(2)_{L} \\otimes SU(2)_{R} \\otimes U(1)_{Y^\\prime}$. The model has several free parameters which here we have calculated by using the recent values for the squared-neutrino mass differences. Lower bound for the mirror vacuum expectation value helped us to obtain crude estimations for some of these parameters. Also we estimate the order of magnitude of the masses of the standard and mirror neutrinos.

  6. Vector-like Fields, Messenger Mixing and the Higgs mass in Gauge Mediation

    CERN Document Server

    Fischler, Willy

    2014-01-01

    In order to generate, in the context of gauge mediation, a Higgs mass around 126 GeV that avoids the little hierarchy problem, we explore a set of models where the messengers are directly coupled to new vector-like fields at the TeV scale in addition to the usual low energy degrees of freedom. We find that in this context, stop masses lighter than 2 TeV and large $A$-terms are generated, thereby improving issues of fine tuning.

  7. Using a biological aerated filter to treat mixed water-borne volatile organic compounds and assessing its emissions

    Institute of Scientific and Technical Information of China (English)

    CHENG Wen-Hsi

    2009-01-01

    A biological aerated filter (BAF) was evaluated as a fixed-biofilm processes to remove water-borne volatile organic compounds (VOCs) from a multiple layer ceramic capacitor (MLCC) manufacturing plant in southern Taiwan.The components of VOC were identified to be toluene,1,2,4-trimethylbenzene,1,3,5-trimethylbenzene,bromodichloromethane and isopropanol (IPA).The full-scale BAF was constructed of two separate reactors in series,respectively using 10-cm and 15-cm diameter polypropylene balls as the packing materials and a successful preliminary bench-scale experiment was performed to feasibility.Performance results show that the BAF removed over 90% chemical oxygen demand (COD) from the influent with (1188 ± 605) mg/L of COD.A total organic loading of 2.76 kg biochemical oxygen demand (BOD)/(m~3 packing·d) was determined for the packed bed,in which the flow pattern approached that of a mixed flow.A limited VOC concentration of (0.97 ± 0.29) ppmv (as methane) was emitted from the BAF system.Moreover,the emission rate of VOC was calculated using the proposed formula,based on an air-water mass equilibrium relationship,and compared to the simulated results obtained using the Water 9 model.Both estimation approaches of calculation and model simulation using Water 9 evaluating VOC emissions reveal that 0.1% IPA (0.0031-0.0037 kg/d) was aerated into a gaseous phase,and 30% to 40% (0.006-0.008 kg/d) of the toluene was aerated.

  8. Biopolymers Production by Mixed Culture and Their Applications in Water and Wastewater Treatment.

    Science.gov (United States)

    More, Tanaji T; Yan, Song; Tyagi, Rajeshwar Dayal; Surampalli, Rao Y

    2015-06-01

    Thirteen extracellular polymeric substances (EPS) producing bacterial strains were cultivated (as pure/mixed culture) in sterilized sludge (suspended solids: 25 g/L). The mixed culture produced higher concentrations of EPS (4.9 g/L) as compared to that of the pure culture (2.7-3.7 g/L). The harvested EPS were examined for their flocculation performance (turbidity removal and dewatering) in jar tests using kaolin suspensions with Ca2+. Broth (B-EPS) revealed high kaolin flocculating activity (91.2%) at very low concentrations (0.8 mg B-EPS/g kaolin) and it was comparable to the chemical polymer, Magnafloc-155 (90.4% at 0.2 mg/g kaolin). B-EPS also exhibited very good flocculation performance (turbidity removal %) in river water (93.5%), municipal wastewater (91.7%) and brewery wastewater (81.8%). The study revealed that the mixed culture consortium could be used for the production of highly efficient flocculants.

  9. Sustainable treatment potential of mixed algal consortia for domestic waste water: Growth and mixotrophy

    Directory of Open Access Journals (Sweden)

    Priyanka Murthy

    2015-04-01

    Full Text Available The increasing levels of generation of nutrient-rich waste water pose serious challenge. Conventional biological and chemical methods of waste water treatment have failed in meeting sustainability challenges. Naturally occurring mixed algal species reared in mixotrophic growth modes have been deployed to recover nutrients (N and P from domestic wastewater after anaerobic digestion. In this paper, we present the results pertaining to growth and mixotrophy. Pilot-scale operation shows that the cultivation methods adopted and the use of naturally selected species lead to a tendency among these species to clump at certain stages of growth that in turn float or settle rapidly making algal harvest and thereby the nutrient recovery processes energy efficient. The highest settling rate was found to be 6.37 ± 1.6 g/m2/d. Mixotrophy was seen to contribute 15 – 24 % across the various algal consortia in wastewater (polyculture.

  10. Plio-Pleistocene evolution of water mass exchange and erosional input at the Atlantic-Arctic gateway

    Science.gov (United States)

    Teschner, Claudia; Frank, Martin; Haley, Brian A.; Knies, Jochen

    2016-05-01

    Water mass exchange between the Arctic Ocean and the Norwegian-Greenland Seas has played an important role for the Atlantic thermohaline circulation and Northern Hemisphere climate. We reconstruct past water mass mixing and erosional inputs from the radiogenic isotope compositions of neodymium (Nd), lead (Pb), and strontium (Sr) at Ocean Drilling Program site 911 (leg 151) from 906 m water depth on Yermak Plateau in the Fram Strait over the past 5.2 Myr. The isotopic compositions of past bottom waters were extracted from authigenic oxyhydroxide coatings of the bulk sediments. Neodymium isotope signatures obtained from surface sediments agree well with present-day deepwater ɛNd signature of -11.0 ± 0.2. Prior to 2.7 Ma the Nd and Pb isotope compositions of the bottom waters only show small variations indicative of a consistent influence of Atlantic waters. Since the major intensification of the Northern Hemisphere Glaciation at 2.7 Ma the seawater Nd isotope composition has varied more pronouncedly due to changes in weathering inputs related to the waxing and waning of the ice sheets on Svalbard, the Barents Sea, and the Eurasian shelf, due to changes in water mass exchange and due to the increasing supply of ice-rafted debris (IRD) originating from the Arctic Ocean. The seawater Pb isotope record also exhibits a higher short-term variability after 2.7 Ma, but there is also a trend toward more radiogenic values, which reflects a combination of changes in input sources and enhanced incongruent weathering inputs of Pb released from freshly eroded old continental rocks.

  11. Application of the Regional Water Mass Variations from GRACE Satellite Gravimetry to Large-Scale Water Management in Africa

    Directory of Open Access Journals (Sweden)

    Guillaume Ramillien

    2014-08-01

    Full Text Available Time series of regional 2° × 2° Gravity Recovery and Climate Experiment (GRACE solutions of surface water mass change have been computed over Africa from 2003 to 2012 with a 10-day resolution by using a new regional approach. These regional maps are used to describe and quantify water mass change. The contribution of African hydrology to actual sea level rise is negative and small in magnitude (i.e., −0.1 mm/y of equivalent sea level (ESL mainly explained by the water retained in the Zambezi River basin. Analysis of the regional water mass maps is used to distinguish different zones of important water mass variations, with the exception of the dominant seasonal cycle of the African monsoon in the Sahel and Central Africa. The analysis of the regional solutions reveals the accumulation in the Okavango swamp and South Niger. It confirms the continuous depletion of water in the North Sahara aquifer at the rate of −2.3 km3/y, with a decrease in early 2008. Synergistic use of altimetry-based lake water volume with total water storage (TWS from GRACE permits a continuous monitoring of sub-surface water storage for large lake drainage areas. These different applications demonstrate the potential of the GRACE mission for the management of water resources at the regional scale.

  12. Recycling of fresh concrete exceeding and wash water in concrete mixing plants

    Directory of Open Access Journals (Sweden)

    Férriz Papí, J. A.

    2014-03-01

    Full Text Available The exceeding concrete and washing equipment water are a matter to solve in concrete production. This paper explains several possibilities for recycling and analyses the products obtained with one recycling equipment. The objective of this work is to study the possibility to increase the percentage of recycling in new mixes. The developed study relates wash water density and fine particles content. Besides, mortar and concrete samples were tested introducing different quantities of these fine particles, substituting cement, sand or only as an addition. Consistency, compressive strength, setting time, absorption, and capillarity were tested. The results indicated an improvement of the studied properties in some percentages when substituting sand. It confirms the possibility to introduce larger quantities of wash water in new concrete mixes, with corrections in sand quantity depending on water density.Los hormigones frescos sobrantes y aguas procedentes de la limpieza de equipos son un inconveniente a resolver en las plantas de hormigón. Este artículo explica varias posibilidades de reciclado y analiza los productos obtenidos en un equipo reciclador concreto, con el objetivo de estudiar el incremento del porcentaje de reciclaje en nuevas amasadas. El estudio realizado relaciona la densidad del agua de lavado y el contenido de partículas finas. Además, ensaya muestras de mortero y hormigón realizando sustituciones de estas partículas finas por cemento, arena o simplemente como adición. Determina consistencia, resistencia a compresión, principio y fin de fraguado, absorción y capilaridad. Los resultados indicaron un incremento general de las propiedades estudiadas en algunos porcentajes de sustitución por arena. Ello confirma la posibilidad de introducir mayores cantidades de agua de lavado en nuevas amasadas de hormigón, mediante correcciones en la dosificación de arena en función de la densidad del agua.

  13. Identification of Unknown Contaminants in Water Samples from ISS Employing Liquid Chromatography/Mass Spectrometry/Mass Spectrometry

    Science.gov (United States)

    Rutz, Jeffrey A.; Schultz, John R.

    2008-01-01

    Mass Spectrometry/Mass Spectrometry (MS/MS) is a powerful technique for identifying unknown organic compounds. For non-volatile or thermally unstable unknowns dissolved in liquids, liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) is often the variety of MS/MS used for the identification. One type of LC/MS/MS that is rapidly becoming popular is time-of-flight (TOF) mass spectrometry. This technique is now in use at the Johnson Space Center for identification of unknown nonvolatile organics in water samples from the space program. An example of the successful identification of one unknown is reviewed in detail in this paper. The advantages of time-of-flight instrumentation are demonstrated through this example as well as the strategy employed in using time-of-flight data to identify unknowns.

  14. Constraints on neutralino masses and mixings from cosmology and collider physics

    Energy Technology Data Exchange (ETDEWEB)

    Langenfeld, U.

    2007-07-15

    Bounds on cross section measurements of chargino pair production at LEP yield a bound on the chargino mass. If the GUT relation is assumed, the lightest neutralino must be heavier than {approx}45-50 GeV. If no GUT relation is assumed, no lower bound on the neutralino mass exists. I derive mass bounds on the lightest neutralino from relic density measurements for relativistic and non-relativistic neutralinos and I derive bounds on the selectron mass from the observed limits on the cross section of the neutralino pair production process e{sup +}e{sup -}{yields} {chi}{sup 0}{sub 1} {chi}{sup 0}{sub 2} at LEP, if the lightest neutralino is massless. I further discuss radiative neutralino production and its background at the future ILC. Finally, I present a method to determine the neutralino couplings to right and left handed selectrons and Z bosons from cross section measurements of radiative neutralino pair production at the ILC. (orig.)

  15. Constraints on neutralino masses and mixings from cosmology and collider physics

    Energy Technology Data Exchange (ETDEWEB)

    Langenfeld, U.

    2007-07-15

    Bounds on cross section measurements of chargino pair production at LEP yield a bound on the chargino mass. If the GUT relation is assumed, the lightest neutralino must be heavier than {approx}45-50 GeV. If no GUT relation is assumed, no lower bound on the neutralino mass exists. I derive mass bounds on the lightest neutralino from relic density measurements for relativistic and non-relativistic neutralinos and I derive bounds on the selectron mass from the observed limits on the cross section of the neutralino pair production process e{sup +}e{sup -}{yields} {chi}{sup 0}{sub 1} {chi}{sup 0}{sub 2} at LEP, if the lightest neutralino is massless. I further discuss radiative neutralino production and its background at the future ILC. Finally, I present a method to determine the neutralino couplings to right and left handed selectrons and Z bosons from cross section measurements of radiative neutralino pair production at the ILC. (orig.)

  16. Models of low-mass helium white dwarfs including gravitational settling, thermal and chemical diffusion, and rotational mixing

    CERN Document Server

    Istrate, Alina; Tauris, Thomas M; Langer, Norbert; Stancliffe, Richard J; Grassitelli, Luca

    2016-01-01

    A large number of extremely low-mass helium white dwarfs (ELM WDs) have been discovered in recent years. The majority of them are found in close binary systems suggesting they are formed either through a common-envelope phase or via stable mass transfer in a low-mass X-ray binary (LMXB) or a cataclysmic variable (CV) system. Here, we investigate the formation of these objects through the LMXB channel with emphasis on the proto-WD evolution in environments with different metallicities. We study, for the first time, the combined effects of rotational mixing and element diffusion (e.g. gravitational settling, thermal and chemical diffusion) on the evolution of proto-WDs and on the cooling properties of the resulting WDs. We present state-of-the-art binary stellar evolution models computed with MESA for metallicities between Z=0.0002 and Z=0.02, producing WDs with masses between 0.16-0.45 M$_{\\odot}$. Our results confirm that element diffusion plays a significant role in the evolution of proto-WDs that experience...

  17. Partitioning of soil water among canopy trees during a soil desiccation period in a temperate mixed forest

    Directory of Open Access Journals (Sweden)

    M. Meißner

    2012-08-01

    Full Text Available Complementary resource use is considered an important mechanism in the study of biodiversity effects. Here we explore how species identity, species mixture and tree size influence the vertical partitioning of soil water among canopy trees during a soil desiccation period. In the Hainich Forest, Germany, the species Fagus sylvatica, Tilia sp. and Fraxinus excelsior were studied in single- and three-species mixed clusters, each consisting of three co-dominant trees situated within a larger mixed forest stand. Vertical soil water uptake depth was assessed by analyzing the hydrogen stable isotope composition (deuterium, δD of water from depth intervals throughout the soil profile and in tree xylem water. For single species clusters, a mixing model suggested that Fagus distinctively drew water from soil depths of 0.3–0.5 m, Tilia from 0.3–0.5 m and 0.5–0.7 m and Fraxinus mainly used water from 0.5–0.7 m. In mixed clusters, the uptake patterns of Fagus and Tilia were similar to those of the single-species clusters (mainly uptake form 0.3–0.5 m, but Fraxinus showed a different uptake pattern. Fraxinus in mixture had a somewhat homogenously distributed uptake over the soil depths 0.2–0.7 m. For single species clusters, there was no correlation between main soil water uptake depth and tree diameter, irrespective of variations in tree size. In contrast, for mixed clusters there was a significant decrease in the main uptake depth with increasing tree size (P<0.001, R2adj = 0.73, irrespective of species mix. In consequence, soil water partitioning was strongest where species were mixed and tree size varied. We further analyzed whether single and mixed-species clusters differed in the level of water uptake, e.g. due to complementarity, but our soil water budgeting did not indicate any such differences. A possible explanation might be

  18. Partitioning of soil water among canopy trees during a soil desiccation period in a temperate mixed forest

    Directory of Open Access Journals (Sweden)

    M. Meißner

    2012-05-01

    Full Text Available Complementary resource use is considered an important mechanism in the study of biodiversity effects. Here we explore how species identity, species mixture and tree size influence the vertical partitioning of soil water among canopy trees during a soil desiccation period. In the Hainich forest, Germany, the species Fagus sylvatica, Tilia sp. and Fraxinus excelsior were studied in single- and three-species mixed clusters, each consisting of three co-dominant trees situated within a larger mixed forest stand. Vertical soil water uptake depth was assessed by analyzing the hydrogen stable isotope composition (deuterium, δ D of water from depth intervals throughout the soil profile and in tree xylem water. For single species clusters, a mixing model suggested that Fagus distinctively drew water from soil depths of 0.3–0.5 m, Tilia from 0.3–0.5 m and 0.5–0.7 m and Fraxinus mainly used water from 0.5–0.7 m. In mixed clusters, the uptake patterns of Fagus and Tilia were similar to those of the single-species clusters (mainly uptake form 0.3–0.5 m, but Fraxinus showed a different uptake pattern. Fraxinus in mixture had a somewhat homogenously distributed uptake over the soil depths 0.2–0.7 m. For single species clusters, there was no correlation between main soil water uptake depth and tree diameter, irrespective of variations in tree size. In contrast, for mixed clusters there was a significant decrease in the main uptake depth with increasing tree size (P<0.001, R2adj = 0.73, irrespective of species mix. In consequence, soil water partitioning was strongest where species were mixed and tree size varied. We further analyzed whether single and mixed-species clusters differed in the level of water uptake, e.g. due to complementarity, but our soil water budgeting did not indicate any such differences. A possible explanation might be that the

  19. Towards a complete theory of fermion masses and mixings with SO(3) Family Symmetry and 5d SO(10) unification

    Energy Technology Data Exchange (ETDEWEB)

    King, Stephen F.; Malinsky, Michal [School of Physics and Astronomy, University of Southampton, Southampton SO16 1BJ (United Kingdom)

    2006-11-15

    We construct a complete 4d model of fermion masses and mixings in the Pati-Salam SU(4)xSU(2){sub L}xSU(2){sub R} framework governed by an SO(3) gauged Family Symmetry. The relevant low energy effective Yukawa operators are constructed so that the SO(3) flavons enter at the simplest possible one-flavon level, with couplings enforced by an additional U(1) x Z{sub 2} symmetry. The simplicity of the flavon sector allows the messenger sector to be fully specified, allowing the ultraviolet completion of the model at the 4d renormalizable level. The model predicts approximate tri-bimaximal lepton mixing via the see-saw mechanism with sequential dominance, and vacuum alignment of flavons, with calculable deviations described by the neutrino sum rule. We perform a numerical analysis of the emerging charged fermion spectra and mixings. The 4d model is shown to result from a 5d orbifold GUT model based on SO(3) x SO(10), where small flavon vacuum expectation values (VEVs) originate from bulk volume suppression.

  20. Supramolecular solvent-based vortex-mixed microextraction: determination of glucocorticoids in water samples.

    Science.gov (United States)

    Qin, Hui; Qiu, Xiaoyan; Zhao, Jiao; Liu, Mousheng; Yang, Yaling

    2013-10-11

    Glucocorticoids contamination has become a big environmental issue in China and other developing countries, due to increasing needs in medical prescription and farming. However, no highly sensitive and precise methods have been reported to quantify glucocorticoids so far. In the past several years, supramolecular solvent-based vortex-mixed microextraction (SS-BVMME) has been shown to be effective. However, the mechanism of SS-BVMME is still unknown. In this report, a novel method has been proposed for rapid quantification of trace amount of glucocorticoids, beclomethasone dipropionate (BD), hydrocortisone butyrate (HB) and nandrolone phenylpropionate (NPP) in water samples from the Green Lake. This method is simple, safe and cost effective. It contains two steps: supramolecular solvent-based vortex-mixed microextraction (SS-BVMME) technique and high performance liquid chromatography (HPLC) analysis. First, ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and n-butanol were mixed to form the supramolecular solvent. After mixing the supramolecular solvent with an aqueous sample to test, a homogenous mixture was formed immediately. BD, HB and NPP were then extracted based on their binding interactions, particularly hydrogen bond formed between their hydroxyl group and the supramolecular solvent. The overall process of sample preparation took only 20min and more than 5 samples could be simultaneously prepared. The minimum detectable concentrations of samples in this method were 0.09925, 0.5429 and 2.428ngmL(-1) for BD, HB and NPP, respectively. Product recoveries ranged from 88% to 103% with relative standard deviations from 0.6% to 4%. For the first time, we report that hydrogen bond plays a key role in SS-BVMME. We also improve the sensitivity significantly to quantify glucocorticoids, which may greatly benefit environmental safety management in China.

  1. THE USE OF DI WATER TO MITIGATE DUSTING FOR ADDITION OF DWPF FRIT TO THE SLURRY MIX EVAPORATOR

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E.

    2010-07-21

    The Defense Waste Processing Facility (DPWF) presently is in the process to determine means to reduce water utilization in the Slurry Mix Evaporator (SME) process, thus reducing effluent and processing times. The frit slurry addition system mixes the dry frit with water, yielding approximately a 50 weight percent slurry containing frit and the other fraction water. This slurry is discharged into the SME and excess water is removed via boiling. To reduce this water load to the SME, DWPF has proposed using a pneumatic system in conveying the frit to the SME, in essence a dry delivery system. The problem associated with utilizing a dry delivery system with the existing frit is the generation of dust when discharged into the SME. The use of water has been shown to be effective in the mining industry as well in the DOE complex to mitigate dusting. The method employed by SRNL to determine the quantity of water to mitigate dusting in dry powders was effective, between a lab and bench scale tests. In those tests, it was shown that as high as five weight percent (wt%) of water addition was required to mitigate dust from batches of glass forming minerals used by the Waste Treatment Plant at Hanford, Washington. The same method used to determine the quantity of water to mitigate dusting was used in this task to determine the quantity of water to mitigate this dusting using as-received frit. The ability for water to mitigate dusting is due to its adhesive properties as shown in Figure 1-1. Wetting the frit particles allows for the smaller frit particles (including dust) to adhere to the larger frit particles or to agglomerate into large particles. Fluids other than water can also be used, but their adhesive properties are different than water and the quantity required to mitigate dusting is different, as was observed in reference 1. Excessive water, a few weight percentages greater than that required to mitigate dusting can cause the resulting material not to flow. The primary

  2. The Mixed-Alkali Effect on The Resistance of Glass to Water

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the composition of float glass, the resistance of glass to water, in which a small amount of K2O (0—1.0 wt%) was substituted for equivalent amount of Na2O, was investigated by means of glass grains testing. The components extracted from the glass and total alkalinities in extraction solution were determined by atomic absorption spectroscopy and neutralizing method, respectively. The composition of the glass was 14.4 K2O+Na2O, 4.0MgO, 8.2CaO, 1.4Al2O3, 72.0 SiO2, and the minimum extraction ratio of oxides (maximum durability) occurred at a K2O/Na2O ratio of 0.051(by weight) due to the presence of the mixed-alkali effect. The relative extraction ratio of alkali oxides (R2O) was greater than that of alkaline earth oxides (RO). By means of mixed-alkali effect and lowing relative contents of R2O in the glass, the resistance of float glass to water was improved and its mildew-proof ability was therefore increased.

  3. Spectrophotometric determination of the acidity constants of calcon in water and mixed water–organic solvents

    Directory of Open Access Journals (Sweden)

    MOHAMMAD MAZLOUM-ARDAKANI

    2009-02-01

    Full Text Available The acid–base properties of calcon (1-(2-hydroxy-1-naphthylazo-2-naphthol-4-sulfonic acid in water and mixed water–organic solvents at 25 °C at an ionic strength of 0.10 M are studied by a multiwavelength spectrophotometric method. The organic solvents used were the amphiprotic (methanol, dipolar aprotic (dimethylsulfoxide, and low basic aprotic (acetonitrile. To evaluate the pH absorbance data, a resolution method based on the combination of soft- and hard-modeling was applied. The acidity constants of all related equilibria were estimated using the whole spectral fitting of the collected data to an established factor analysis model. The data analysis program Datan was applied for determination of the acidity constants. The corresponding pKa values were determined in water and mixed water–organic solvents. Linear relationship between the acidity constants and the mole fraction of the different sol-vents in the mixtures exist. The effect of solvent properties on acid–base behavior is discussed.

  4. Land cover and water yield: inference problems when comparing catchments with mixed land cover

    Directory of Open Access Journals (Sweden)

    A. I. J. M. van Dijk

    2012-09-01

    Full Text Available Controlled experiments provide strong evidence that changing land cover (e.g. deforestation or afforestation can affect mean catchment streamflow (Q. By contrast, a similarly strong influence has not been found in studies that interpret Q from multiple catchments with mixed land cover. One possible reason is that there are methodological issues with the way in which the Budyko framework was used in the latter type studies. We examined this using Q data observed in 278 Australian catchments and by making inferences from synthetic Q data simulated by a hydrological process model (the Australian Water Resources Assessment system Landscape model. The previous contrasting findings could be reproduced. In the synthetic experiment, the land cover influence was still present but not accurately detected with the Budyko- framework. Likely sources of interpretation bias demonstrated include: (i noise in land cover, precipitation and Q data; (ii additional catchment climate characteristics more important than land cover; and (iii covariance between Q and catchment attributes. These methodological issues caution against the use of a Budyko framework to quantify a land cover influence in Q data from mixed land-cover catchments. Importantly, however, our findings do not rule out that there may also be physical processes that modify the influence of land cover in mixed land-cover catchments. Process model simulations suggested that lateral water redistribution between vegetation types and recirculation of intercepted rainfall may be important.

  5. Lepton Flavor Mixing Pattern and Neutrino Mass Matrix after the Daya Bay Experiment

    CERN Document Server

    Zhou, Shun

    2012-01-01

    The Daya Bay Collaboration has recently observed neutrino oscillations in the nu_e-bar -> nu_e-bar disappearance channel, indicating that sin^2 theta_13 = 0.024 +(-) 0.005 (1 sigma) and theta_13 = 0 is already excluded at the 5.2 sigma confidence level. Now three neutrino mixing angles have been measured to a good degree of accuracy (theta_12 ~ 34^\\circ, theta_23 ~ 45^\\circ and theta_13 ~ 9^\\circ). Motivated by these experimental results, we propose a novel lepton flavor mixing pattern, which predicts sin^2 theta_23 = 1/2, sin^2 theta_12 = (2+\\sqrt{3})/(10+\\sqrt{3}) ~ 0.318 and sin^2 theta_13 = (2-\\sqrt{3})/12 ~ 0.022, together with a maximal CP-violating phase delta = 90^\\circ. The leptonic CP violation characterized by the Jarlskog invariant {\\cal J} = \\sqrt{6}/72 ~ 3.4 % is promising to be measured in the future long-baseline neutrino oscillation experiments. Furthermore, we point out that a generalized version of mu-tau symmetry may exist in the neutrino sector and can give rise to the aforementioned mixi...

  6. Determination of seven pyrethroids and six pyrethrins in water by liquid chromatography/mass spectrometry

    Science.gov (United States)

    ccanccapa, alexander; Masia, Ana; Pico, Yolanda

    2016-04-01

    Pyrethroids are the synthetic analogues of pyrethrins which were developed as pesticides from the extracts of dried and powdered flower heads of Chrysanthemum cinerariaefolium. They are increasingly used in agriculture due to their broad biological activity and slow development of pest resistance. Contamination of fresh-water ecosystems appears either because of the direct discharge of industrial and agricultural effluents or as a result of effluents from sewage treatment works; residues can thus accumulate in the surrounding biosphere [1, 2]. These substances, mostly determined by gas chromatography mass spectrometry (GC-MS) can be difficult to analyse due to their volatility and degradability. The purpose of this study is, as an alternative, to develop a fast and sensitive multi-residue method for the target analysis of 7 pyrethroids and the 6 natural pyrethrins currently used in water samples by liquid chromatography tandem mass spectrometry (LC-MS/MS). The compounds included in the study were acrinathrin, etofenprox, cyfluthrin, esfenvalerate, cyhalothrin, cypermethrin and flumethrin as pyrethroids and a commercial mix of pyrethrins containing Cinerin I, Jasmolin I, pyrethrin I, cinerin II, jasmolin II, pyrethrins II in different percentages. As a preliminary step, the ionization and fragmentation of the compounds were optimized injecting individual solutions of each analyte at 10 ppm in the system, using a gradient elution profile of water-methanol both with 10 mM ammonium formate. The ESI conditions were: capillary voltage 4000 V, nebulizer15 psi, source temperature 300◦C and gas flow 10 L min-1. [M+H]+, [M+Na]+ ,[M+NH3]+ ,[M+NH4+]+ were tested as precursor ions. The most intense signal was for ammonium adduct for all compounds. The optimal fragmentor range for product ions were between 20 to 80 ev and the collision energy ranged between 5 to 86 ev. The efficiency of the method was tested in water samples from Turia River without any known exposure to

  7. Experimental and Numerical Studies of Controlling Thermal Cracks in Mass Concrete Foundation by Circulating Water

    OpenAIRE

    Wenchao Liu; Wanlin Cao; Huiqing Yan; Tianxiang Ye; Wang Jia

    2016-01-01

    This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China), as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and the atmospheric environment. The temperature gradient between the surface and the core of the mass con...

  8. Carbonized mix kerosene and water with cavitation method as an alternative energy

    Science.gov (United States)

    Casnan, Irzaman

    2017-03-01

    The world's population continuously grows at a quarter million people per day. This fast-growing population had raised the world energy consumption up to 474 × 1018 J per year with 80 to 90 percent derived from the combustion of fossil fuels. It is estimated that the fossil energy will be lasted in 42 years. Rice husk is an alternative of non-fossil energy that may be utilized in traditional way of cooking (burning it in a traditional stove). However, burning the husk produces some carbon gasses that may pollute the air. In order to reduce the gas pollution, the gas may be mixed with kerosene and water using sonochemical technique to produce dry steam. This steam is a good fuel for a traditional stove. It is confirmed that 1 liter of water can be boiled in 11 minutes when the temperature of the water is 95°C while the stove is 264°C. the sonochemical technique had successfully increased the efficiency of the energy consumption of the stove up to 17%. The carbonized fuel is also not expensive since its cost is only around 6 C (IDR 570) for boiling 1 liter of water.

  9. Hammerhead ribozyme activity and oligonucleotide duplex stability in mixed solutions of water and organic compounds

    Directory of Open Access Journals (Sweden)

    Shu-ichi Nakano

    2014-01-01

    Full Text Available Nucleic acids are useful for biomedical targeting and sensing applications in which the molecular environment is different from that of a dilute aqueous solution. In this study, the influence of various types of mixed solutions of water and water-soluble organic compounds on RNA was investigated by measuring the catalytic activity of the hammerhead ribozyme and the thermodynamic stability of an oligonucleotide duplex. The compounds with a net neutral charge, such as poly(ethylene glycol, small primary alcohols, amide compounds, and aprotic solvent molecules, added at high concentrations changed the ribozyme-catalyzed RNA cleavage rate, with the magnitude of the effect dependent on the NaCl concentration. These compounds also changed the thermodynamic stability of RNA base pairs of an oligonucleotide duplex and its dependence on the NaCl concentration. Specific interactions with RNA molecules and reduced water activity could account for the inhibiting effects on the ribozyme catalysis and destabilizing effects on the duplex stability. The salt concentration dependence data correlated with the dielectric constant, but not with water activity, viscosity, and the size of organic compounds. This observation suggests the significance of the dielectric constant effects on the RNA reactions under molecular crowding conditions created by organic compounds.

  10. Development of a nucleotide sugar purification method using a mixed mode column & mass spectrometry detection.

    Science.gov (United States)

    Eastwood, Heather; Xia, Fang; Lo, Mei-Chu; Zhou, Jing; Jordan, John B; McCarter, John; Barnhart, Wesley W; Gahm, Kyung-Hyun

    2015-11-10

    Analysis of nucleotide sugars, nucleoside di- and triphosphates and sugar-phosphates is an essential step in the process of understanding enzymatic pathways. A facile and rapid separation method was developed to analyze these compounds present in an enzymatic reaction mixture utilized to produce nucleotide sugars. The Primesep SB column explored in this study utilizes hydrophobic interactions as well as electrostatic interactions with the phosphoric portion of the nucleotide sugars. Ammonium formate buffer was selected due to its compatibility with mass spectrometry. Negative ion mode mass spectrometry was adopted for detection of the sugar phosphate (fucose-1-phophate), as the compound is not amenable to UV detection. Various mobile phase conditions such as pH, buffer concentration and organic modifier were explored. The semi-preparative separation method was developed to prepare 30mg of the nucleotide sugar. (19)F NMR was utilized to determine purity of the purified fluorinated nucleotide sugar. The collected nucleotide sugar was found to be 99% pure.

  11. Evaluation of a mass-balance approach to determine consumptive water use in northeastern Illinois

    Science.gov (United States)

    Mills, Patrick C.; Duncker, James J.; Over, Thomas M.; Marian Domanski,; ,; Engel, Frank

    2014-01-01

    A principal component of evaluating and managing water use is consumptive use. This is the portion of water withdrawn for a particular use, such as residential, which is evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. The amount of consumptive use may be estimated by a water (mass)-balance approach; however, because of the difficulty of obtaining necessary data, its application typically is restricted to the facility scale. The general governing mass-balance equation is: Consumptive use = Water supplied - Return flows.

  12. Impact of Chemical Reaction on MHD Mixed Convection Heat and Mass Transfer Flow with Thermophoresis

    Directory of Open Access Journals (Sweden)

    Prabir Kumar KUNDU

    2014-02-01

    Full Text Available A mathematical model is analyzed in order to study the effects of chemical reaction and thermophoresis on MHD mixed convection boundary layer flow of an incompressible, electrically conducting fluid past a heated vertical permeable flat plate embedded in a uniform porous medium, by taking into account the radiative heat flux and variable suction. The governing partial differential equations are transformed into a set of coupled ordinary differential equations which are solved analytically using the regular perturbation technique. Numerical results for dimensionless velocity, temperature, concentration as well as the skin friction coefficient, Nusselt number and Sherwood number are presented through graphs and a table for pertinent parameters to show interesting aspects of the solution.doi:10.14456/WJST.2014.35

  13. Water masses and zonal current in the Western Tropical Atlantic in October 2007 and January 2008 (AMANDES project

    Directory of Open Access Journals (Sweden)

    A. C. Silva

    2010-11-01

    Full Text Available The properties and circulation of water masses are examined using data collected from a hydrographic and Acoustic Doppler Current profiler in the Western Tropical Atlantic during two cruises of the GEOTRACES process study "AMANDES" (AMazon-ANDEans: AMANDES I (October–November 2007 and AMANDES II (January 2008. In the upper layer (from the sea surface to 150 m means of vertical sections of velocity are showing the structure of the Current (NBC and North Equatorial Countercurrent. In the lower layer (below 150 m the subsurface velocity core of the North Brazil UnderCurrent, Western Boundary Undercurrent (WBUC and northern branch of the South Equatorial Current (nSEC could be observed. In October the WBUC flows southeastward with a velocity of about 0.3 m s−1. In the studied area during October 2007, the NBUC and nSEC are transporting South Atlantic Central Water (SACW from the Southern Hemisphere whereas the WBUC transports North Atlantic Central Water (NACW southeastward. In the deep layers, the North Atlantic Deep Water (NADW is composed of three components: the Upper North Atlantic Deep Water – UNADW (between 1310 and 1650 m, the Middle North Atlantic Deep Water (between 1930 and 2400 m, the Lower North Atlantic Deep Water (centered around 3430 m.

    Off Guyana, the Antartic Intermediate Water (AAIW changes of composition between October 2007 (45.2% ACW, 32.2% AAIWsource and 22.6% UNADW and January 2008 (62.4% ACW, 23.5% AAIWsource and 14.1% UNADW.

    These intermediate waters are significantly warmer, less oxygenated and saltier than their southern source, reflecting both oxygen consumption and mixing with the Atlantic Central Water (ACW and the Upper North Atlantic Deep Water during their northward transit.

  14. Influence of runoff, high frequency atmospheric forcing and model resolution on deep water mass formation regions and Atlantic Meridional Overturning Circulation, from a numerical model.

    Science.gov (United States)

    Garcia Quintana, Yarisbel; Courtois, Peggy; Hu, Xianmin; Pennelly, Clark; Myers, Paul G.

    2016-04-01

    Water mass formation regions act as windows to the deep ocean where surface waters are transformed to intermediate and deep waters. Within the North Atlantic, Labrador Sea Water (LSW) is convectively produced in the Labrador Sea while in the Nordic Seas the source waters for Denmark Strait Overflow Water (DSOW) and Iceland-Scotland Overflow Water (NEADW) are formed. They are the main components of the North Atlantic Deep Water (NADW) which forms the lower limb of the Atlantic Meridional Overturning Circulation (AMOC). We explore the changes of the LSW formation rates and in AMOC strength as consequence of runoff glacial melt, high frequency atmospheric forcing influence and variations in model's resolution. We use 1/4° resolution Arctic and Northern Hemisphere Atlantic (ANHA4) configuration from the Nucleus for European Modelling of the Ocean (NEMO) model. A nest using ANHA4 and the Adaptive Grid Refinement in FORTRAN (AGRIF) package was used to increase the resolution to 1/12° in the sub-polar gyre. The formation rate is calculated based upon a kinematic subduction approach where the exchange through the dynamic mixed layer base is calculated based on shallowing and deepening in the mixed layer, and convergence of horizontal transport into or out of the mixed layer. Lastly we use a Lagrangian tool (Ariane) to track the path of the DSOW and the NEADW from their formation source.

  15. Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA

    Science.gov (United States)

    Crandall, Christy A.; Katz, Brian G.; Hirten, Joshua J.

    Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88m above mean sea level in April 1996 and discharge peaked at 360m3/s. During these high-flow conditions, water from the Suwannee River migrated directly into the karstic Upper Floridan aquifer, the main source of water supply for the area. Changes in the chemical composition of groundwater were quantified using naturally occurring geochemical tracers and mass-balance modeling techniques. Mixing of river water with groundwater was indicated by a decrease in the concentrations of calcium, silica, and 222Rn; and by an increase in dissolved organic carbon (DOC), tannic acid, and chloride, compared to low-flow conditions in water from a nearby monitoring well, Wingate Sink, and Little River Springs. The proportion (fraction) of river water in groundwater ranged from 0.13 to 0.65 at Wingate Sink and from 0.5 to 0.99 at well W-17258, based on binary mixing models using various tracers. The effectiveness of a natural tracer in quantifying mixing of river water and groundwater was related to differences in tracer concentration of the two end members and how conservatively the tracer reacted in the mixed water. Solutes with similar concentrations in the two end-member waters (Na, Mg, K, Cl, SO4, SiO2) were not as effective tracers for quantifying mixing of river water and groundwater as those with larger differences in end-member concentrations (Ca, tannic acid, DOC, 222Rn, HCO3). Résumé Les aquifères karstiques sont particulièrement sensibles à l'infiltration rapide d'eau de rivières, spécialement pendant les périodes de hautes eaux. A la suite d'une période de pluies soutenues sur le bassin de la rivière Suwannee (Floride, États-Unis), le niveau de cette rivière est monté de 3,0 à 5,88m au-dessus du niveau

  16. Ocean Circulation and Water Mass Characteristics around the Galápagos Archipelago Simulated by a Multiscale Nested Ocean Circulation Model

    Directory of Open Access Journals (Sweden)

    Yanyun Liu

    2014-01-01

    Full Text Available Ocean circulation and water mass characteristics around the Galápagos Archipelago are studied using a four-level nested-domain ocean system (HYCOM. The model sensitivity to atmospheric forcing frequency and spatial resolution is examined. Results show, that with prescribed atmospheric forcing, HYCOM can generally simulate the major El Niño events especially the strong 1997-1998 events. Waters surrounding the archipelago show a large range of temperature and salinity in association with four different current systems. West zones of Isabella and Fernandina Islands are the largest upwelling zones, resulting from the collision of the Equatorial Undercurrent (EUC with the islands, bringing relatively colder, salty waters to the surface and marking the location of the highest biological production. Model results, which agree well with observations, show a seasonal cycle in the transport of the EUC, reaching a maximum during the late spring/early summer and minimum in the late fall. The far northern region is characterized by warmer, fresher water with the greatest mixed layer depth as a result of Panama Current waters entering from the northeast. Water masses over the remainder of the region result from mixing of cool Peru Current waters and upwelled Cold Tongue waters entering from the east.

  17. Assessing the contribution of water to the mass closure of PM10

    Science.gov (United States)

    Perrino, C.; Catrambone, M.; Farao, C.; Canepari, S.

    2016-09-01

    The data obtained during a number of field studies aimed at determining the chemical composition of atmospheric particulate matter (PM) have shown that the measurement of the main PM components (main elements, ions, elemental carbon, organic carbon) was generally sufficient to obtain a reasonable mass closure. Notwithstanding, a wide gap between PM mass concentration and reconstructed mass was observed in two peculiar environmental conditions: desert dust intrusion and severe atmospheric stability episodes characterized by very high ammonium nitrate concentration. In these two cases, the mass closure improved significantly by adding the concentration of PM-bound water. Water was determined by using a coulometric Karl-Fisher system equipped with a controlled heating device; the method was able to separate different water contributions released in different temperature ranges from 50 to 250 °C. In our field studies the amount of water associated to ammonium salts in winter stability conditions was mostly dependent on ammonium nitrate concentration and constituted up to 22% of the total PM10 mass; the specific water contribution linked to ammonium salts (released in the temperature range 180-250 °C) constituted up to 30% of the ammonium nitrate mass. It was confirmed that in these extreme conditions quartz and Teflon filters behave differently: when measured on quartz filters, PM concentration was lower than on Teflon, the mass closure was satisfactory and the concentration of water was presumably very low. In the case of desert dust episodes, water was up to 10% of total PM10 mass; the specific water contribution linked to desert dust (released in the temperature range 100-180 °C) constituted about 5% of the mass of soil components. In other environmental situations, such as urban environments, marine atmosphere and rural areas, the concentration of PM-bound water was below 2-3 μg/m3.

  18. Influence of thermal radiation on mixed convection heat and mass transfer stagnation-point flow in nanofluids over stretching/shrinking sheet in a porous medium with chemical reaction

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Dulal, E-mail: dulalp123@rediffmail.com [Department of Mathematics, Visva-Bharati University, Siksha-Bhavana, Santiniketan, West Bengal 731 235 (India); Mandal, Gopinath [Siksha-Satra, Visva-Bharati, Sriniketan, West Bengal 731 236 (India)

    2014-07-01

    Highlights: • Concentration increases with Schmidt number for stretching and shrinking sheets. • Copper–water nanofluid has higher skin-friction coefficient and mass transfer rate. • Sherwood number decreases for higher values of nanoparticle volume fraction. • Cu–water has lower heat transfer rate compared to Al{sub 2}O{sub 3}–water and TiO{sub 2}–water. • Skin-friction increases with porous parameter and nanoparticle volume fraction. - Abstract: We have investigated the mixed convection boundary layer flow of nanofluids on a stagnation-point flow over a permeable stretching/shrinking sheet subject to thermal radiation, heat source/sink, viscous dissipation and chemical reaction by using numerical method. Three types of nanofluids namely copper–water, alumina–water, titanium dioxide–water were considered in the present study. The governing boundary layer equations are transformed into a system of nonlinear ordinary differential equations by using similarity transformation which are then solved numerically using fifth-order Runge–Kutta–Fehlberg method with shooting technique. The effects of various physical parameters are analyzed and discussed in graphical and tabular form. The effects of some physical parameters such as mixed convection parameter, radiation parameter, Schimdt number, porous parameter, Eckert number, chemical reaction parameter are analyzed on velocity, temperature and concentration profiles as well as on skin-friction coefficient, local Nusselt number and Sherwood number. It is found that copper–water exhibits higher mass transfer rates compared to alumina–water and titanium dioxide–water nanofluids for stretching and shrinking sheets.

  19. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2009-01-15

    , hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 at Laxemar (November 30 2007). The data interpretation was carried out during November 2007 to September 2008. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. The original works by the ChemNet modellers are presented in four level III reports containing complementary information for the bedrock hydrogeochemistry Laxemar Site Descriptive Model (SDM-Site Laxemar, R-08-93) level II report. There is also a fifth level III report: Fracture mineralogy of the Laxemar area (R-08-99). This report presents the modelling work performed by the UZ (Univ. of Zaragoza) group as part of the work plan for Laxemar-Simpevarp 2.2 and 2.3. The main processes determining the global geochemical evolution of the Laxemar-Simpevarp groundwaters system are mixing and reaction processes. Mixing has taken place between different types of waters (end members) over time, making the discrimination of the main influences not always straightforward. Several lines of evidence suggest the input of dilute waters (cold or warm), at different stages, into a bedrock with pre-existing very saline groundwaters. Subsequently, marine water entered the system over the Littorina period (when the topography and the distance to the coast allowed it) and mixed with pre-existent groundwaters of variable salinity. In the Laxemar subarea mainland, the Littorina input occurred only locally and it has mostly been flushed out by the subsequent input of warm meteoric waters with a distinctive modern isotopic signature. In addition to mixing processes and superimposed to their

  20. Mixing It Up With MT2: Unbiased Mass Measurements at Hadron Colliders

    CERN Document Server

    Curtin, David

    2011-01-01

    Recently, much progress has been made on techniques to measure the masses of new particles with partially-invisible decays at a hadron collider. We examine for the first time the realistic application of MT2-based measurement methods to a fully hadronic final state from a symmetric two-step decay chain with maximal combinatorial uncertainty. Several problems arise in such an analysis: the MT2 variables are powerful but fragile, with shallow edges that are easily washed out or faked by ubiquitous combinatorics background. Traditional methods of both cleaning up the distribution and determining edge position can fail badly. To perform successful mass measurements we introduce several new techniques: the Edge-to-Bump method of extracting an edge from a distribution by analyzing a distribution of fits rather than a single fit; a very simple yet high-yield method for determining decay-chain assignments event-by-event; and a systematic procedure to obtain MT2 edge measurements in the presence of heavy combinatorics...

  1. The Physiological Response to Cold Water Immersion Following a Mixed Martial Arts Training Session.

    Science.gov (United States)

    Lindsay, Angus; Carr, Sam; Cross, Sean; Petersen, Carl; Lewis, John G; Gieseg, Steven P

    2017-01-17

    Combative sport is one of the most physically intense forms of exercise, yet the effect of recovery interventions has been largely unexplored. We investigated the effect of cold water immersion on structural, inflammatory and physiological stress biomarkers following a mixed martial arts contest preparation training session in comparison to passive recovery. Semi-professional MMA competitors (n=15) were randomly assigned to a cold water immersion (15 min at 10°C) or passive recovery protocol (ambient air) completed immediately following a contest preparation training session. Markers of muscle damage (urinary myoglobin), inflammation/oxidative stress (urinary neopterin + total neopterin (neopterin + 7,8-dihydroneopterin)) and hypothalamic-pituitary axis activation (saliva cortisol) were determined before, immediately post and one, two and 24 hours post-session. Ratings of perceived soreness and fatigue, counter movement jump and gastrointestinal temperature were also measured. Concentrations of all biomarkers increased significantly (p<0.05) post-session. Cold water immersion attenuated increases in urinary neopterin (p<0.05, d = 0.58), total neopterin (p<0.05, d = 0.89) and saliva cortisol after two hours (p<0.05, d = 0.68) and urinary neopterin again at 24 hours (p<0.01, d = 0.57) in comparison to passive recovery. Perceived soreness, fatigue and gastrointestinal temperatures were also lower for the cold water immersion group at several time points post-session whilst counter movement jump did not differ. Combative sport athletes who are subjected to impact-induced stress may benefit from immediate cold water immersion as a simple recovery intervention that reduces delayed onset muscle soreness as well as macrophage and HPA activation whilst not impairing functional performance.

  2. Extension of the QUASAR river water quality model to incorporate dead-zone mixing

    Directory of Open Access Journals (Sweden)

    M. J. Lees

    1998-01-01

    Full Text Available A modification to the well-known water quality model 'Quality Simulation Along River Systems' (QUASAR is presented, extending its utility to real-time forecasting applications such as the management and control of pollution incidents. Two aggregated dead-zone (ADZ parameters, namely time delay and dispersive fraction, are incorporated into the existing model formulation, extending the current continuously stirred tank reactor based model processes to account for advective and active mixing volume dispersive processes. The resulting river water quality model combines the strengths of the QUASAR model, which has proven non-conservative pollutant modelling capabilities, with the accurate advection and dispersion characterisation of the ADZ model. A discrete-time mathematical representation of the governing equations is developed that enables efficient system identification methods of parameter estimation to be utilised. The enhanced water quality model and associated methods of parameter estimation are validated using data from tracer experiments conducted on the River Mimram. The revised model produces accurate predictions of observed concentration-time curves for conservative substances.

  3. Extension of the QUASAR river water quality model to incorporate dead-zone mixing

    Science.gov (United States)

    Lees, M. J.; Camacho, L.; Whitehead, P.

    A modification to the well-known water quality model "Quality Simulation Along River Systems" (QUASAR) is presented, extending its utility to real-time forecasting applications such as the management and control of pollution incidents. Two aggregated dead-zone (ADZ) parameters, namely time delay and dispersive fraction, are incorporated into the existing model formulation, extending the current continuously stirred tank reactor based model processes to account for advective and active mixing volume dispersive processes. The resulting river water quality model combines the strengths of the QUASAR model, which has proven non-conservative pollutant modelling capabilities, with the accurate advection and dispersion characterisation of the ADZ model. A discrete-time mathematical representation of the governing equations is developed that enables efficient system identification methods of parameter estimation to be utilised. The enhanced water quality model and associated methods of parameter estimation are validated using data from tracer experiments conducted on the River Mimram. The revised model produces accurate predictions of observed concentration-time curves for conservative substances.

  4. LABORATORY SIMULATION OF POROUS ASPHALT PARKING LOT SYSTEM AND MIX DESIGN FOR STORM WATER MANAGEMENT

    Directory of Open Access Journals (Sweden)

    M. O. HAMZAH

    2013-04-01

    Full Text Available Porous asphalt pavement was initially developed for the purpose of improving road safety, best candidate material for quiet pavement and to avoid aquaplaning and skidding in wet weather. However, from previous studies, porous asphalt is able to mitigate surface runoff. Porous asphalt parking lots with underlying reservoir course perform as additional temporary water storage matrix that enables reduction of flash flood. This paper elaborates the development of a new porous asphalt aggregate grading design for storm water mitigation using the Nominal Maximum Aggregate Size (NMAS 20 mm. The properties of the mixes were quantified and evaluated in terms of air voids, permeability, abrasion loss and indirect tensile strength. It was found that the proposed gradation has the best permeability and Indirect Tensile Strength (ITS values when compacted at 50 blows per face with a standard Marshal compactor. The porous asphalt slab was prepared using a slab compactor to simulate porous parking lot paving at site. The porous asphalt slab was finally placed inside a locally fabricated water flow simulator to simulate a porous asphalt pavement system for parking lots.

  5. Influence of rapid mix, flocculation and decantation parameters on the treatment of the Ponta Grossa/PR water treatment plant affluent water

    Directory of Open Access Journals (Sweden)

    Fabiano Icker Oroski

    2009-08-01

    Full Text Available Brazilian regulations, NBR 12216 (1992, admit that, in the absence of laboratory and pilot plant data, rapid mix, flocculation, decantation or dissolved air flotation parameters be adopted. The present work demonstrates that this is a dangerous practice, which can compromise or difficult the water treatment plant operation, and can leave to a serious damages on the treated water quality; as well can conduct to a bigger operational costs. Therefore, in this work it was evaluated the influence of rapid mix, flocculation and decantation parameters on the treatment of the raw water affluent to the water treatment plant of Ponta Grossa City, Parana State, Brazil. As coagulant agents it was applied aluminium sulfate, PACI (polyaluminium chloride, ferric chloride and Fenton reagent. It was observed that the mentioned parameters must not be adopted because exert a big influence on turbidity removal efficiency.Keywords: rapid mix; flocculation; decantation; alum; fenton reagent.

  6. Modeling the improvement of ultrafiltration membrane mass transfer when using biofiltration pretreatment in surface water applications.

    Science.gov (United States)

    Netcher, Andrea C; Duranceau, Steven J

    2016-03-01

    In surface water treatment, ultrafiltration (UF) membranes are widely used because of their ability to supply safe drinking water. Although UF membranes produce high-quality water, their efficiency is limited by fouling. Improving UF filtrate productivity is economically desirable and has been attempted by incorporating sustainable biofiltration processes as pretreatment to UF with varying success. The availability of models that can be applied to describe the effectiveness of biofiltration on membrane mass transfer are lacking. In this work, UF water productivity was empirically modeled as a function of biofilter feed water quality using either a quadratic or Gaussian relationship. UF membrane mass transfer variability was found to be governed by the dimensionless mass ratio between the alkalinity (ALK) and dissolved organic carbon (DOC). UF membrane productivity was optimized when the biofilter feed water ALK to DOC ratio fell between 10 and 14. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Increase of Total Body Water with Decrease of Body Mass while Running 100 km Nonstop--Formation of Edema?

    Science.gov (United States)

    Knechtle, Beat; Wirth, Andrea; Knechtle, Patrizia; Rosemann, Thomas

    2009-01-01

    We investigated whether ultraendurance runners in a 100-km run suffer a decrease of body mass and whether this loss consists of fat mass, skeletal muscle mass, or total body water. Male ultrarunners were measured pre- and postrace to determine body mass, fat mass, and skeletal muscle mass by using the anthropometric method. In addition,…

  8. Increase of Total Body Water with Decrease of Body Mass while Running 100 km Nonstop--Formation of Edema?

    Science.gov (United States)

    Knechtle, Beat; Wirth, Andrea; Knechtle, Patrizia; Rosemann, Thomas

    2009-01-01

    We investigated whether ultraendurance runners in a 100-km run suffer a decrease of body mass and whether this loss consists of fat mass, skeletal muscle mass, or total body water. Male ultrarunners were measured pre- and postrace to determine body mass, fat mass, and skeletal muscle mass by using the anthropometric method. In addition,…

  9. Livestock and feed water productivity in the mixed crop-livestock system.

    Science.gov (United States)

    Bekele, M; Mengistu, A; Tamir, B

    2017-02-22

    Recently with limited information from intensified grain-based farming systems in developed countries, livestock production is challenged as being huge consumer of freshwater. The smallholder mixed crop-livestock (MCL) system which is predominant in developing countries like Ethiopia, is maintained with considerable contributions of crop residues (CR) to livestock feeding. Inclusion of CR is expected to reduce the water requirement for feed production resulting improvement in livestock water productivity (LWP). This study was conducted to determine feed water productivity (FWP) and LWP in the MCL system. A multistage sampling procedure was followed to select farmers from different wealth status. Wealth status dictated by ownership of key farm resources such as size of cropland and livestock influenced the magnitude of livestock outputs, FWP and LWP. Significant difference in feed collected, freshwater evapotranspired, livestock outputs and water productivity (WP) were observed between wealth groups, where wealthier are relatively more advantaged. Water productivity of CR and grazing land (GL) analyzed separately showed contrasting differences where better-off gained more on CR, whereas vice versa on GL. These counterbalancing of variations may justify the non-significant difference in total FWP between wealth groups. Despite observed differences, low WP on GL indicates the need of interventions at all levels. The variation in WP of CR is attributed to availability of production factors which restrained the capacity of poor farmers most. A linear relationship between the proportion of CR in livestock feed and FWP was evident, but the relationship with LWP was not likely linear. As CR are inherently low in digestibility and nutritive values which have an effect on feed conversion into valuable livestock products and services, increasing share of CR beyond an optimum level is not a viable option to bring improvements in livestock productivity as expressed in terms of

  10. Mixing regime as a key factor to determine DON formation in drinking water biological treatment.

    Science.gov (United States)

    Lu, Changqing; Li, Shuai; Gong, Song; Yuan, Shoujun; Yu, Xin

    2015-11-01

    Dissolved organic nitrogen (DON) can act as precursor of nitrogenous disinfection by-products formed during chlorination disinfection. The performances of biological fluidized bed (continuous stirred tank reactor, CSTR) and bio-ceramic filters (plug flow reactor, PFR) were compared in this study to investigate the influence of mixing regime on DON formation in drinking water treatment. In the shared influent, DON ranged from 0.71mgL(-1) to 1.20mgL(-1). The two biological fluidized bed reactors, named BFB1 (mechanical stirring) and BFB2 (air agitation), contained 0.12 and 0.19mgL(-1) DON in their effluents, respectively. Meanwhile, the bio-ceramic reactors, labeled as BCF1 (no aeration) and BCF2 (with aeration), had 1.02 and 0.81mgL(-1) DON in their effluents, respectively. Comparative results showed that the CSTR mixing regime significantly reduced DON formation. This particular reduction was further investigated in this study. The viable/total microbial biomass was determined with propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) and qPCR, respectively. The results of the investigation demonstrated that the microbes in BFB2 had higher viability than those in BCF2. The viable bacteria decreased more sharply than the total bacteria along the media depth in BCF2, and DON in BCF2 accumulated in the deeper media. These phenomena suggested that mixing regime determined DON formation by influencing the distribution of viable, total biomass, and ratio of viable biomass to total biomass.

  11. Prediction of Solid-Liquid Equilibrium for KCl in Mixed Water-Ethanol Solutions Using the LIQUAC Model

    Institute of Scientific and Technical Information of China (English)

    LIN Yangzheng; LI Jiding; ZENG Chuyi; CHEN Cuixian

    2005-01-01

    The LIQUAC model is often used to predict vapor-liquid equilibria, osmotic coefficients, and mean ion activity coefficients for electrolyte systems. This paper describes a thermodynamic method to analyze solid-liquid equilibrium for electrolytes in mixed solvents solutions using the LIQUAC model. The KCl solubilities in mixed water-ethanol solutions are predicted with the LIQUAC model and its original interaction parameters. This method is also used to obtain new K+-ethanol interaction parameters in the LIQUAC model from the solubility data. The new interaction parameters accurately predict the vapor-liquid equilibrium data of K+ salts (including KCl, KBr, and KCOOCH3) in mixed water-ethanol solutions. The results illustrate the flexibility of the LIQUAC model which can predict not only vapor-liquid equilibrium but also solid-liquid equilibrium in mixed solvent systems.

  12. Nitrite toxicity of Litopenaeus vannamei in water containing low concentrations of sea salt or mixed salts

    Science.gov (United States)

    Sowers, A.; Young, S.P.; Isely, J.J.; Browdy, C.L.; Tomasso, J.R.

    2004-01-01

    The uptake, depuration and toxicity of environmental nitrite was characterized in Litopenaeus vannamei exposed in water containing low concentrations of artificial sea salt or mixed salts. In 2 g/L artificial sea salts, nitrite was concentrated in the hemolymph in a dose-dependent and rapid manner (steady-state in about 2 d). When exposed to nitrite in 2 g/L artificial sea salts for 4 d and then moved to a similar environment without added nitrite, complete depuration occurred within a day. Increasing salinity up to 10 g/L decreased uptake of environmental nitrite. Nitrite uptake in environments containing 2 g/L mixed salts (combination of sodium, potassium, calcium and magnesium chlorides) was similar to or lower than rates in 2 g/L artificial sea salt. Toxicity was inversely related to total dissolved salt and chloride concentrations and was highest in 2 g/L artificial sea salt (96-h medial lethal concentration = 8.4 mg/L nitrite-N). Animals that molted during the experiments did not appear to be more susceptible to nitrite than animals that did not molt. The shallow slope of the curve describing the relationship between toxicity and salinity suggests that management of nitrite toxicity in low-salinity shrimp ponds by addition of more salts may not be practical. ?? Copyright by the World Aquaculture Society 2004.

  13. Gravimetric analysis, ionic composition, and associated water mass of the marine aerosol

    Science.gov (United States)

    McInnes, L. M.; Quinn, P. K.; Covert, D. S.; Anderson, T. L.

    Measurements of the total aerosol mass and ionic composition were obtained for submicrometer ( Dp ⩽ 1.0 μm) aerosol particles from the remote Pacific boundary layer by gravimetric and ion chromatography analysis. Discrepancies were found to exist between the absolute mass determined by the separate techniques suggesting aerosol components in addition to sea salt and sulfate particles exist at significant mass concentrations. The gravimetric mass was equal to or significantly larger than the sum of the ionic masses, suggesting additional aerosol components contribute between 0 and 75% of the submicrometer aerosol mass. Measurements of the elemental composition of individual particles by electron microscopy confirmed the presence of mineral and carbonaceous particles which contributed 0-86% of the total number concentration for the particle-size range of interest. The relative number of submicrometer sulfate particles with respect to the total was low during periods with the largest discrepancy between the gravimetric and ionic mass. The amount of water associated with the submicrometer aerosol at 47% relative humidity made up 29% of the total aerosol mass collected on the filters (and 9% of the total mass at 35%). Laboratory studies determined the relative amount of water associated with sea salt, sulfate, and sodium chloride particles on a filter substrate, with sea-salt particles containing 27% water and ammonium sulfate particles containing only 4% water at 40% r.h.

  14. Managing mixed fisheries in the European western waters: application of Fcube methodology

    DEFF Research Database (Denmark)

    Iriondo, Ane; García, Dorleta; Santurtún, Marina

    2012-01-01

    Fisheries management is moving towards ecosystem based management instead of traditional single species based advice. To progress towards an ecosystem approach, a new methodology called “Fleet and Fisheries Forecast” (Fcube) has been proposed. In the application of the method, a precise initial f...... the lowest. In this analysis, Western Waters fleet management results show consistency between stocks and their respective TACs. The study highlights that it is possible to deliver advice within the context of mixed fisheries using the Fcube method......Fisheries management is moving towards ecosystem based management instead of traditional single species based advice. To progress towards an ecosystem approach, a new methodology called “Fleet and Fisheries Forecast” (Fcube) has been proposed. In the application of the method, a precise initial...

  15. A hybrid water-splitting cycle using copper sulfate and mixed copper oxides

    Science.gov (United States)

    Schreiber, J. D.; Remick, R. J.; Foh, S. E.; Mazumder, M. M.

    1980-01-01

    The Institute of Gas Technology has derived and developed a hybrid thermochemical water-splitting cycle based on mixed copper oxides and copper sulfate. Similar to other metal oxide-metal sulfate cycles that use a metal oxide to 'concentrate' electrolytically produced sulfuric acid, this cycle offers the advantage of producing oxygen (to be vented) and sulfur dioxide (to be recycled) in separate steps, thereby eliminating the need of another step to separate these gases. The conceptual process flow-sheet efficiency of the cycle promises to exceed 50%. It has been completely demonstrated in the laboratory with recycled materials. Research in the electrochemical oxidation of sulfur dioxide to produce sulfuric acid and hydrogen performed at IGT indicates that the cell performance goals of 200 mA/sq cm at 0.5 V will be attainable using relatively inexpensive electrode materials.

  16. Studies on Recast-layer in EDM using Aluminium Powder Mixed Distilled Water Dielectric Fluid

    Directory of Open Access Journals (Sweden)

    Khalid Hussain Syed

    2013-04-01

    Full Text Available In this paper, an attempt has been made to study the effect of aluminium powder when mixed in the distilled water dielectric fluid. The work and tool electrode materials used are W300 diesteel and electrolytic copper respectively. Pulse peak current, pulse on-time and concentration of aluminium powder are taken as the process parameters. The output response considered is white layer thickness (WLT. The experiments are planned using face centered central composite design procedure. Empirical model is developed for WLT using response surface methodology (RSM to study the effect ofprocess parameters. Optical microscopy results show that low thickness of white-layer 17.14 μm is obtained at high concentration of powder of 4 g/l and low peak current of 6 A.

  17. Ionothermal synthesis process for aluminophosphate molecular sieves in the mixed water/ionic liquid system.

    Science.gov (United States)

    Zhao, Zhenchao; Zhang, Weiping; Xu, Renshun; Han, Xiuwen; Tian, Zhijian; Bao, Xinhe

    2012-01-21

    The synthesis process of aluminophosphate AlPO(4)-11 molecular sieve in the mixed water/1-butyl- 3-methylimidazolium bromide ([bmim]Br) ionic liquid was investigated by XRD, multinuclear solid-state NMR, scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS). It was observed that a tablet phase, named SIZ-2, was formed at the early stage of crystallization. During crystallization metastable SIZ-2 with an incompletely condensed framework phosphorus disappeared gradually, and the phosphorous species became fully condensed through hydroxyl reaction with tetrahedral aluminum to form thermodynamically stable AlPO(4)-11 in the final product. It was found that [bmim]Br, acting as the structure-directing agent, was occluded into the AlPO(4)-11 channel.

  18. Thermohaline structure and water masses in the north of Antarctic Peninsula from data collected in situ by southern elephant seals (Mirounga leonina

    Directory of Open Access Journals (Sweden)

    Ilana E. K. C. Wainer

    2013-04-01

    Full Text Available The Western Antarctic Peninsula is rapidly warming and exhibits high indices of biodiversity concentrated mostly along its continental shelf. This region has great importance due to the the mixing caused by the interaction of waters from Weddell Sea (MW, Bransfield Strait (EB and the Antarctic Circumpolar Current (CCA transmits thermohaline characteristics and nutrients of different sites and finally connects with all the world’s oceans. However, studies focusing on the temporal variability of the region’s oceanographic conditions that finally determine the water mass formation are sparse due to the logistical difficulties of conducting oceanographic surveys and traditional monitoring during the winter. For this study, variations of the thermohaline structure and water masses in the vicinity and below the sea ice in the North of the Antarctic Peninsula (AP and Scotia Sea (SS were recorded between February and November 2008 by two female southern elephant seals (SES, Mirounga leonina tagged with Conductivity–Temperature–Depth/Satellite-Relay Data Logger (CTD–SRDL. One thousand three hundred and thirty vertical profiles of temperature and salinity were collected by seals which were tagged by the MEOP-BR Project team at the Elephant Island, South Shetlands. These profiles, together with spread state diagrams allowed the identification of water masses and their variances in the ocean’s vertical structure. Among the set of identified water masses we cite: Antarctic Surface Water (AASW, Winter Water (WW, Warm Deep Water (WDW, Modified Warm Deep Water (MWDW, Circumpolar Deep Water (CDW, Upper Circumpolar Deep Water (UCDW, Lower Circumpolar Deep Water (LCDW and Ice Shelf Water (ISW. Our results show that the oceanic vertical structure undergoes changes that cannot be traditionally monitored, particularly during the Austral winter and that SES are important and modern oceanographic data collection platforms allowing for the improvement of our

  19. Modeling the Thermodynamics of Mixed Organic-Inorganic Aerosols to Predict Water Activities and Phase Equilibria

    Science.gov (United States)

    Zuend, A.; Marcolli, C.; Luo, B.; Peter, T.

    2008-12-01

    Tropospheric aerosol particles contain mixtures of inorganic salts, acids, water, and a large variety of organic compounds. Interactions between these substances in liquid mixtures lead to discrepancies from ideal thermodynamic behavior. While the thermodynamics of aqueous inorganic systems at atmospheric temperatures are well established, little is known about the physicochemistry of mixed organic-inorganic particles. Salting-out and salting-in effects result from organic-inorganic interactions and are used to improve industrial separation processes. In the atmosphere, they may influence the aerosol phases. Liquid-liquid phase separations into a mainly polar (aqueous) and a less polar organic phase may considerably influence the gas/particle partitioning of semi-volatile substances compared to a single phase estimation. Moreover, the phases present in the aerosol define the reaction medium for heterogeneous and multiphase chemistry occurring in aerosol particles. A correct description of these phases is needed when gas- or cloud-phase reaction schemes are adapted to aerosols. Non-ideal thermodynamic behavior in mixtures is usually described by an expression for the excess Gibbs energy. We present the group-contribution model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients), which explicitly accounts for molecular interactions between solution constituents, both organic and inorganic, to calculate activities, chemical potentials and the total Gibbs energy of mixed systems. This model allows to compute vapor-liquid (VLE), liquid-liquid (LLE) and solid-liquid (SLE) equilibria within one framework. Focusing on atmospheric applications we considered eight different cations, five anions and a wide range of alcohols/polyols as organic compounds. With AIOMFAC, the activities of the components within an aqueous electrolyte solution are very well represented up to high ionic strength. We show that the semiempirical middle

  20. Thorium-based mixed oxide fuel in a pressurized water reactor: A feasibility analysis with MCNP

    Science.gov (United States)

    Tucker, Lucas Powelson

    This dissertation investigates techniques for spent fuel monitoring, and assesses the feasibility of using a thorium-based mixed oxide fuel in a conventional pressurized water reactor for plutonium disposition. Both non-paralyzing and paralyzing dead-time calculations were performed for the Portable Spectroscopic Fast Neutron Probe (N-Probe), which can be used for spent fuel interrogation. Also, a Canberra 3He neutron detector's dead-time was estimated using a combination of subcritical assembly measurements and MCNP simulations. Next, a multitude of fission products were identified as candidates for burnup and spent fuel analysis of irradiated mixed oxide fuel. The best isotopes for these applications were identified by investigating half-life, photon energy, fission yield, branching ratios, production modes, thermal neutron absorption cross section and fuel matrix diffusivity. 132I and 97Nb were identified as good candidates for MOX fuel on-line burnup analysis. In the second, and most important, part of this work, the feasibility of utilizing ThMOX fuel in a pressurized water reactor (PWR) was first examined under steady-state, beginning of life conditions. Using a three-dimensional MCNP model of a Westinghouse-type 17x17 PWR, several fuel compositions and configurations of a one-third ThMOX core were compared to a 100% UO2 core. A blanket-type arrangement of 5.5 wt% PuO2 was determined to be the best candidate for further analysis. Next, the safety of the ThMOX configuration was evaluated through three cycles of burnup at several using the following metrics: axial and radial nuclear hot channel factors, moderator and fuel temperature coefficients, delayed neutron fraction, and shutdown margin. Additionally, the performance of the ThMOX configuration was assessed by tracking cycle length, plutonium destroyed, and fission product poison concentration.

  1. Evaluation of Aerosol Mixing State Classes in the GISS Modele-matrix Climate Model Using Single-particle Mass Spectrometry Measurements

    Science.gov (United States)

    Bauer, Susanne E.; Ault, Andrew; Prather, Kimberly A.

    2013-01-01

    Aerosol particles in the atmosphere are composed of multiple chemical species. The aerosol mixing state, which describes how chemical species are mixed at the single-particle level, provides critical information on microphysical characteristics that determine the interaction of aerosols with the climate system. The evaluation of mixing state has become the next challenge. This study uses aerosol time-of-flight mass spectrometry (ATOFMS) data and compares the results to those of the Goddard Institute for Space Studies modelE-MATRIX (Multiconfiguration Aerosol TRacker of mIXing state) model, a global climate model that includes a detailed aerosol microphysical scheme. We use data from field campaigns that examine a variety of air mass regimens (urban, rural, and maritime). At all locations, polluted areas in California (Riverside, La Jolla, and Long Beach), a remote location in the Sierra Nevada Mountains (Sugar Pine) and observations from Jeju (South Korea), the majority of aerosol species are internally mixed. Coarse aerosol particles, those above 1 micron, are typically aged, such as coated dust or reacted sea-salt particles. Particles below 1 micron contain large fractions of organic material, internally-mixed with sulfate and black carbon, and few external mixtures. We conclude that observations taken over multiple weeks characterize typical air mass types at a given location well; however, due to the instrumentation, we could not evaluate mass budgets. These results represent the first detailed comparison of single-particle mixing states in a global climate model with real-time single-particle mass spectrometry data, an important step in improving the representation of mixing state in global climate models.

  2. Seasonal evolution of the Yellow Sea Cold Water Mass and its interactions with ambient hydrodynamic system

    Science.gov (United States)

    Li, Jianchao; Li, Guangxue; Xu, Jishang; Dong, Ping; Qiao, Lulu; Liu, Shidong; Sun, Pingkuo; Fan, Zhisong

    2016-09-01

    The Yellow Sea Cold Water Mass (YSCWM) is an important component of the hydrodynamic system in the South Yellow Sea (SYS). However, its intricate interactions with the ambient flows over long time scales are not fully understood. This paper presents the analysis of the data set obtained from a seabed-mounted Acoustic Doppler Current Profiler (ADCP) deployed for nearly 1 year in the western SYS. It allowed us to study the evolution of YSCWM, including the seasonal changes of tidal currents, near-inertial oscillations (NIOs), and the wind-driven currents due to typhoons and winter storms. Strong NIOs were found near the bottom of mixed layer and in the pycnocline with nearly opposite current directions, with maximum velocity of nearly 20 cm·s-1 in summer. The YSCWM can also inhibit the direct downward energy transport in the water column due to typhoons. Conversely, the hydrodynamic system also feeds back to influence the change of YSCWM. A large current shear (S) of 20 cm·s-1·m-1 is generated near the top of pycnocline. Generally, the intensity and depth of the pycnocline determine S's magnitude and vertical location, respectively. Based on the monthly averaged density profile data, the Richardson number and wavelet analysis, the NIOs are considered to be capable of inducing predominant shear instability around the pycnocline. However, the NIOs are not strong enough to influence the lower YSCWM. In addition, in autumn, each fortnightly spring tide corresponds with a bottom temperature increase of nearly 2°C, indicating that tidal currents are the leading hydrodynamic driving force to decline the YSCWM.

  3. Field-testing of a Passive Surface Water Flux Meter for the Direct Measurement of Water and Solute Mass Fluxes

    Science.gov (United States)

    Atkinson, E. C.; Jawitz, J. W.; Annable, M. D.; Klammler, H.; Hatfield, K.

    2007-05-01

    The measurement of water and solute mass discharges in surface water flow systems is a fundamental hydrologic task for ecological and economic decision making. However, due to the extensive monetary, labor, and time costs of traditional monitoring devices and methods, many water quality monitoring programs lack the resources necessary to provide comprehensive descriptions of surface water impairments. The Passive Surface Water Flux Meter (PSFM) is a recently developed passive sampling device that measures water and solute fluxes within flowing surface water bodies. Devoid of mechanical components and power supply requirements, the relatively low-maintenance, low-cost design of the PSFM gives it considerable potential as a tool for extensive, large-scale surface water quality characterization and monitoring. The novelty of the PSFM extends to its direct mass-based approach to solute flux measurement, as compared to conventional, indirect concentration-based approaches. During this field-testing campaign, the PSFM was deployed in flowing surface water bodies of north- central Florida. The device contained a dual-packed porous media cartridge that performed simultaneous ion exchange to determine phosphate mass flux and equilibrium tracer desorption to determine water flux within the stream. The PSFM demonstrated accurate measurement of steady-state water and phosphate mass fluxes to within 15% over a range of stream velocities, solute concentrations, and deployment durations. The PSFM design described here was found to perform well in steady-flow conditions. The device was also shown to be effective under transient conditions of limited variability, but full transient testing remains for future work.

  4. Rapid screening of mixed edible oils and gutter oils by matrix-assisted laser desorption/ionization mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Tsz-Tsun; So, Pui-Kin; Zheng, Bo [Food Safety and Technology Research Centre, State Key Laboratory of Chirosciences and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom Kowloon, Hong Kong Special Administrative Region (China); Shenzhen Key Laboratory of Food Biological Safety Control and State Key Laboratory of Chinese Medicine and Molecular Pharmacology (Incubation), Shenzhen Research Institute of The Hong Kong Polytechnic University, Shenzhen (China); Yao, Zhong-Ping, E-mail: zhongping.yao@polyu.edu.hk [Food Safety and Technology Research Centre, State Key Laboratory of Chirosciences and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom Kowloon, Hong Kong Special Administrative Region (China); Shenzhen Key Laboratory of Food Biological Safety Control and State Key Laboratory of Chinese Medicine and Molecular Pharmacology (Incubation), Shenzhen Research Institute of The Hong Kong Polytechnic University, Shenzhen (China)

    2015-07-16

    Highlights: • Simplified sample preparation method for direct analysis of edible oils by MALDI-MS. • Establishment of a preliminary MALDI-MS spectral database of edible oils. • Rapid screening of mixed edible oils and gutter oils. - Abstract: Authentication of edible oils is a long-term issue in food safety, and becomes particularly important with the emergence and wide spread of gutter oils in recent years. Due to the very high analytical demand and diversity of gutter oils, a high throughput analytical method and a versatile strategy for authentication of mixed edible oils and gutter oils are highly desirable. In this study, an improved matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) method has been developed for direct analysis of edible oils. This method involved on-target sample loading, automatic data acquisition and simple data processing. MALDI-MS spectra with high quality and high reproducibility have been obtained using this method, and a preliminary spectral database of edible oils has been set up. The authenticity of an edible oil sample can be determined by comparing its MALDI-MS spectrum and principal component analysis (PCA) results with those of its labeled oil in the database. This method is simple and the whole process only takes several minutes for analysis of one oil sample. We demonstrated that the method was sensitive to change in oil compositions and can be used for measuring compositions of mixed oils. The capability of the method for determining mislabeling enables it for rapid screening of gutter oils since fraudulent mislabeling is a common feature of gutter oils.

  5. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2008-08-15

    in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. This report presents the modelling work performed by the University of Zaragoza group as part of the work planned for Forsmark during stages 2.2 and 2.3. The chemical characteristics of the groundwaters in the Forsmark and Laxemar areas are the result of a complex mixing process driven by the input of different recharge waters since the last glaciation. The successive penetration at different depths of dilute glacial melt-waters, Littorina Sea waters and dilute meteoric waters has triggered complex density and hydraulically driven flows that have mixed them with long residence time, highly saline waters present in the fractures and in the rock matrix. A general description of the main characteristics and processes controlling the hydrogeochemical evolution with depth in the Forsmark groundwater system is presented in this report: The hydrochemical characteristics and evolution of the Near surface waters (up to 20 m depth) is mainly determined by weathering reactions and especially affected by the presence of limestones. The biogenic CO{sub 2} input (derived from decay of organic matter and root respiration) and the associated weathering of carbonates control the pH and the concentrations of Ca and HCO{sub 3}- in the near-surface environment. Current seasonal variability of CO{sub 2} input produces variable but high calcium and bicarbonate contents in the Forsmark near-surface waters: up to 240 mg/L Ca and 150 to

  6. A microdevice for the mixing of a highly viscous biosample with water/membrane protein solution using microchannel and centrifugation.

    Science.gov (United States)

    Yuan, Liang; Zheng, Yuan F

    2011-02-01

    A mechanism for controlling the mixing of highly viscous biosamples at the microliter scale is presented. Existing methods for mixing biosamples using microstirrers or shaking microwells are only effective for non-highly viscous materials. The proposed mechanism mixes monoolein, a highly viscous biosample, with water/membrane protein solution in a microdevice called microcapsule using a microchannel and centrifugation. To achieve effective mixing, the design of the microcapsule along with the microchannel is presented and so is the hydrodynamic model describing the flow of viscous materials in the microchannel. The mixing process is analyzed according to the Reynolds number of the biosamples using computer simulation, which is observed during the experiment using digital images for further analysis. Finally, the new approach is verified by X-ray diffraction experiments with water and the Rh membrane protein solution, which are used to evaluate the effectiveness of mixing. Experimental results not only validate the proposed method but also determine the flow oscillation time in the microchannel to achieve effective and efficient mixing.

  7. Improving Water Quality in Construction Site Runoff: Optimal Mixing Time and Dose for Flocculating Suspended Sediment with Polyacrylamide

    Science.gov (United States)

    Zare, A. H.

    2015-12-01

    Sediment, a major water pollutant, can harm ecosystems and water resources. Sediment in construction site runoff can be controlled through flocculation using anionic, linear polyacrylamide (PAM), but there is little information on optimizing these applications. We conducted laboratory experiments to determine the optimal mixing times for varying concentrations of two types of polyacrylamide, APS 705 and FA 920, which are blends of polymers with a range of molecular weights that are anionic and neutral, respectively. These were selected from a variety of PAMs previously screened for flocculation potential. Soil from three active construction sites in the Piedmont region of North Carolina were used in the testing. A mixing speed of 300 revolutions per minute (RPM), the maximum available for the paddle mixer we used, was the most effective at reducing turbidity with PAM. Turbidity was reduced with increased mixing times up to a point, after which little additional benefit was evident. For all three soils tested, turbidity decreased as mixing time reached 1-2 minutes at polymer doses of 1, 5 and 10 mg L-1, with no substantial reduction with further mixing. At a polymer dose of 0.5 mg L-1, however, turbidity tended to increase beyond 5 minutes of mixing time, possibly because excessive shear forces destroyed sparsely linked floc. For both PAMs, 1 mg L-1 and a mixing time of 2-3 min appeared to be sufficient to achieve the most effective turbidity reduction.

  8. On the implications of aerosol liquid water and phase separation for organic aerosol mass

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains data presented in the figures of the paper "On the implications of aerosol liquid water and phase separation for organic aerosol mass"...

  9. Biomarker Pigment Divinyl Chlorophyll a as a Tracer of Water Masses?

    Science.gov (United States)

    Mejdandzic, Maja; Mihanovic, Hrvoje; Silovic, Tina; Henderiks, Jorijntje; Supraha, Luka; Polovic, Dorotea; Bosak, Suncica; Bosnjak, Ivana; Cetinic, Ivona; Olujic, Goran; Ljubesic, Zrinka

    2015-01-01

    The ecological preferences of different Phytoplankton types drive their temporal and spatial distributions, reflecting their dependence on certain temperature ranges, light levels, nutrient availability and other environmental gradients. Hence, some phytoplankton taxa can be used as water mass tracers (biotracers).

  10. A semiconductor/mixed ion and electron conductor heterojunction for elevated-temperature water splitting.

    Science.gov (United States)

    Ye, Xiaofei; Melas-Kyriazi, John; Feng, Zhuoluo A; Melosh, Nicholas A; Chueh, William C

    2013-10-01

    Photoelectrochemical cells (PECs) have been studied extensively for dissociating water into hydrogen and oxygen. Key bottlenecks for achieving high solar-to-hydrogen efficiency in PECs include increasing solar spectrum utilization, surmounting overpotential losses, and aligning the absorber/electrochemical redox levels. We propose a new class of solid-state PECs based on mixed ionic and electronic conducting (MIEC) oxides that operates at temperatures significantly above ambient and utilizes both the light and thermal energy available from concentrated sunlight to dissociate water vapor. Unlike thermochemical and hybrid photo-thermochemical water-splitting routes, the elevated-temperature PEC is a single-step approach operating isothermally. At the heart of the solid-state PEC is a semiconductor light absorber coated with a thin MIEC layer for improved catalytic activity, electrochemical stability, and ionic conduction. The MIEC, placed between the gas phase and the semiconductor light absorber, provides a facile path for minority carriers to reach the water vapor as well as a path for the ionic carriers to reach the solid electrolyte. Elevated temperature operation allows reasonable band misalignments at the interfaces to be overcome, reduces the required overpotential, and facilitates rapid product diffusion away from the surface. In this work, we simulate the behavior of an oxygen-ion-conducting photocathode in 1-D. Using the detailed-balance approach, in conjunction with recombination and electrochemical reaction rates, the practical efficiency is calculated as a function of temperature, solar flux, and select material properties. For a non-degenerate light absorber with a 2.0 eV band-gap and an uphill band offset of 0.3 eV, an efficiency of 17% and 11% is predicted at 723 and 873 K, respectively.

  11. Exploring Localized Mixing Dynamics during Wet Weather in a Tidal Fresh Water System

    Directory of Open Access Journals (Sweden)

    Ramona Stammermann

    2014-04-01

    Full Text Available A recently validated 3-dimensional implementation of the Environmental Fluid Dynamic Code (EFDC for the tidal-fresh portions of the Delaware Estuary was exercised against the results of a dye release from a sewer outfall during a storm. The influence on dye distribution in the estuary resulting from variations in wind and local storm water discharges in an urban area is investigated. The modeled domain stretches 116 km from the head of tide and includes hydrologic input from 33 streams and a number of municipal and industrial discharges. Bottom roughness was parameterized from sedimentological and geophysical surveys. Model validation to-date relies upon field observations and tidal harmonics for sea level and currents derived from the NOAA-NOS 1984–1985 circulation survey and a current survey conducted by the Philadelphia Water Department (PWD. Model representation of dye distribution compared favorably for observations of concentrations in the dye plume from 10 cross-sections spanning the extent of the plume over seven tidal cycles. The dye distribution was characterized by an initial period of high local storm water and stream inflows with low wind conditions, lasting for several tidal cycles, followed by a period of reduced fresh water input and increasing wind stress. The dye experiment provided a unique opportunity to observe the performance of the model through the transition between these two very different meteorological periods, and to explore the physical conditions driving the hydrodynamics through both observations and numerical experiments. The influences of local meteorological forcing and channel morphology on lateral mixing, dispersion and longitudinal dynamics are characterized.

  12. Concrete Durability. Influence of chloride ions concentrations in mixing water and dissolution

    Directory of Open Access Journals (Sweden)

    López Villarino, Begoña

    1995-03-01

    Full Text Available The most aggressive situation which is responsible for most of the cases of steel reinforcement corrosion in concrete, takes place when chlorides are present in the environment. These chlorides destroy the passivating film of steel and promote the denominated pitting corrosion. In order to study the demonstrated corrosive action of chloride ions on concrete structures, a number of experiments have been designed, to quantify the effect of different amounts of this ion in concrete. Several mixes have been prepared with portland cement type II-C-35 to which it has been added, as an additive in mixing water, NaCl in increasing concentrations. The samples obtained were submerged in different dissolutions of NaCl. From the results obtained it is clear that the chloride content in mixing water does not affect the flux of calcium ions; however, its influence on the flux of chloride ions is significant. Likewise, it is confirmed that the existence of chloride ions in dissolution influences the migration of calcium and chloride ions.

    La situación más agresiva, y la responsable del mayor número de casos de corrosión de armaduras en el hormigón, se da cuando en el ambiente hay presencia de cloruros, pues éstos destruyen de forma puntual la capa pasivante del acero, lo que provoca la denominada corrosión por picaduras. Con objeto de estudiar la demostrada acción perniciosa de los cloruros sobre las estructuras de hormigón, se ha diseñado un conjunto de ensayos con el fin de cuantificar el efecto de las distintas cantidades de este ion en la masa de hormigón. Se han realizado diversas amasadas con cemento tipo II-C-35 a las que se añadió, como aditivo en el agua de amasado, NaCl en concentraciones crecientes. Las probetas obtenidas se sumergieron en disoluciones de NaCl de distintas concentraciones. De los resultados obtenidos se deduce que la presencia de cloruros en el agua de amasado no afecta al flujo de iones cálcicos, mientras

  13. An Assessment of Southern Ocean Water Masses and Sea Ice During 1988-2007 in a Suite of Interannual CORE-II Simulations

    Science.gov (United States)

    Downes, Stephanie M.; Farneti, Riccardo; Uotila, Petteri; Griffies, Stephen M.; Marsland, Simon J.; Bailey, David; Behrens, Erik; Bentsen, Mats; Bi, Daohua; Biastoch, Arne; Canuto, Vittorio M.; Howard, Armando; Kelley, Maxwell; Leboissetier, Anthony

    2015-01-01

    We characterise the representation of the Southern Ocean water mass structure and sea ice within a suite of 15 global ocean-ice models run with the Coordinated Ocean-ice Reference Experiment Phase II (CORE-II) protocol. The main focus is the representation of the present (1988-2007) mode and intermediate waters, thus framing an analysis of winter and summer mixed layer depths; temperature, salinity, and potential vorticity structure; and temporal variability of sea ice distributions. We also consider the interannual variability over the same 20 year period. Comparisons are made between models as well as to observation-based analyses where available. The CORE-II models exhibit several biases relative to Southern Ocean observations, including an underestimation of the model mean mixed layer depths of mode and intermediate water masses in March (associated with greater ocean surface heat gain), and an overestimation in September (associated with greater high latitude ocean heat loss and a more northward winter sea-ice extent). In addition, the models have cold and fresh/warm and salty water column biases centred near 50 deg S. Over the 1988-2007 period, the CORE-II models consistently simulate spatially variable trends in sea-ice concentration, surface freshwater fluxes, mixed layer depths, and 200-700 m ocean heat content. In particular, sea-ice coverage around most of the Antarctic continental shelf is reduced, leading to a cooling and freshening of the near surface waters. The shoaling of the mixed layer is associated with increased surface buoyancy gain, except in the Pacific where sea ice is also influential. The models are in disagreement, despite the common CORE-II atmospheric state, in their spatial pattern of the 20-year trends in the mixed layer depth and sea-ice.

  14. Effects of water stress and seed mass on germination and ...

    African Journals Online (AJOL)

    enoh

    2012-03-01

    Mar 1, 2012 ... important restriction factors to seed germination because of the delay in its initiation or ... has little rain, resulting in water as a limiting factor to plant growth. ..... The influence of seed size, shape and treatment on inbred seed ...

  15. Volatile Delivery to Planets from Water-rich Planetesimals around Low Mass Stars

    CERN Document Server

    Ciesla, Fred J; Pascucci, Ilaria; Apai, Daniel

    2015-01-01

    Most models of volatile delivery to accreting terrestrial planets assume that the carriers for water are similar in water content to the carbonaceous chondrites in our Solar System. Here we suggest that the water content of primitive bodies in many planetary systems may actually be much higher, as carbonaceous chondrites have lost some of their original water due to heating from short-lived radioisotopes that drove parent body alteration. Using N-body simulations, we explore how planetary accretion would be different if bodies beyond the water line contained a water mass fraction consistent with chemical equilibrium calculations, and more similar to comets, as opposed to the more traditional water-depleted values. We apply this model to consider planet formation around stars of different masses and identify trends in the properties of Habitable Zone planets and planetary system architecture which could be tested by ongoing exoplanet census data collection. Comparison of such data with the model predicted tren...

  16. Model description of dibenzothiophene mass transfer in oil/water dispersions with respect to biodesulfurization

    NARCIS (Netherlands)

    Marcelis, C.L.M.; Leeuwen, van M.; Polderman, H.G.; Janssen, A.J.H.; Lettinga, G.

    2003-01-01

    A mathematical model was developed in order to describe the mass transfer rate of dibenzothiophene within the oil droplet to the oil/water interface of droplets created in a stirred tank reactor. The mass transfer rate of dibenzothiophene was calculated for various complex hydrocarbon distillates an

  17. Solute mass exchange between water phase and biofilm for a single pore

    NARCIS (Netherlands)

    Qin, C. Z.; Hassanizadeh, S. M.

    2015-01-01

    Currently, there are no tractable approaches available for modeling non-equilibrium mass exchange of a solute between water phase and biofilm in porous media. The present work contributes to a quantitative description of the mass exchange of a solute over a single pore domain under a wide range of p

  18. Hydrography and water masses in the southeastern Arabian Sea during March-June 2003

    Indian Academy of Sciences (India)

    S S C Shenoi; D Shankar; G S Michael; J Kurian; K K Varma; M R Ramesh Kumar; A M Almeida; A S Unnikrishnan; W Fernandes; N Barreto; C Gnanaseelan; R Mathew; K V Praju; V Mahale

    2005-10-01

    This paper describes the hydrographic observations in the southeastern Arabian Sea (SEAS)during two cruises carried out in March –June 2003 as part of the Arabian Sea Monsoon Experiment.The surface hydrography during March –April was dominated by the intrusion of low-salinity waters from the south;during May –June,the low-salinity waters were beginning to be replaced by the high- salinity waters from the north.There was considerable mixing at the bottom of the surface mixed layer,leading to interleaving of low-salinity and high-salinity layers.The flow paths constructed following the spatial patterns of salinity along the sections mimic those inferred from numerical models.Time-series measurements showed the presence of Persian Gulf and Red Sea Waters in the SEAS to be intermittent during both cruises:they appeared and disappeared during both the fortnight-long time series.

  19. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2009-01-15

    , hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on available primary data from the extended data freeze L2.3 at Laxemar (November 30 2007). The data interpretation was carried out during November 2007 to September 2008. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. The original works by the ChemNet modellers are presented in four level III reports containing complementary information for the bedrock hydrogeochemistry Laxemar Site Descriptive Model (SDM-Site Laxemar, R-08-93) level II report. There is also a fifth level III report: Fracture mineralogy of the Laxemar area (R-08-99). This report presents the modelling work performed by the UZ (Univ. of Zaragoza) group as part of the work plan for Laxemar-Simpevarp 2.2 and 2.3. The main processes determining the global geochemical evolution of the Laxemar-Simpevarp groundwaters system are mixing and reaction processes. Mixing has taken place between different types of waters (end members) over time, making the discrimination of the main influences not always straightforward. Several lines of evidence suggest the input of dilute waters (cold or warm), at different stages, into a bedrock with pre-existing very saline groundwaters. Subsequently, marine water entered the system over the Littorina period (when the topography and the distance to the coast allowed it) and mixed with pre-existent groundwaters of variable salinity. In the Laxemar subarea mainland, the Littorina input occurred only locally and it has mostly been flushed out by the subsequent input of warm meteoric waters with a distinctive modern isotopic signature. In addition to mixing processes and superimposed to their

  20. Water and Electricity Do Mix: Studying Plates, Petroleum, and Permafrost using Marine Electromagnetism

    Science.gov (United States)

    Constable, S.

    2015-12-01

    Marine magnetotelluric (MT) and controlled-source electromagnetic (CSEM) sounding methods were developed in the early 1980's as deep-water academic tools to study the oceanic lithosphere and mantle. Electrical conductivity is a strong function of porosity, temperature, melting, and volatile content, and so marine MT and CSEM data can be used to address a variety of geological questions related to plate tectonics. These include the distribution of melt at mid-ocean ridges, the fate of fluids in subduction zones, and the nature of the lithosphere-asthenosphere boundary. With the advent of deepwater oil and gas drilling in the late 1990's, marine EM methods were embraced by the exploration community, and are now routinely used to assist in exploration and make drilling decisions for wells costing $100M or more. For countries without conventional hydrocarbon resources, gas hydrate offers the potential for energy production, and marine CSEM methods may be the only effective way to explore for and characterize this resource. The use of EM methods to map geothermal, groundwater, and mineral resources also has application in the marine environment. Water and electricity has proved to be a very successful mix!

  1. Portable mixed abrasive water jet equipment for rescue in high gas mine shaft

    Institute of Scientific and Technical Information of China (English)

    ZENG Rui; DU Chang-long; XU Rui; ZHAO Jing

    2011-01-01

    In order to rescue a trapped miner and clean out roadways quickly in a high gas mine shaft after a mining mishap, a special portable cold-cutting equipment is needed, the main technology parameters were calculated according to the advanced cold-cutting technology of high pressure abrasive water jet and the portable mixed abrasive water jet equipment (PAWE) was designed to meet the needs of emergency rescue in high gas mine shafts. Tested the PAWE in a high gas environment, and the result shows that the maximum cutting depth of solid iron pipe is 18 mm and the recoilforce of the sprayer is 28.9 N under the conditions that actual cutting pressure is 29 MPa, starting target distance is 10 mm, cutting speed is 180 mm/min and concentration of abrasive is 32%. The course of the experiment in the high gas environment was smooth and continuous, without any explosion. The PAWE is easy to move and operate, but the nozzle which was worn badly in the sprayer should be changed every 8 minutes.

  2. Evaporative assembly of MEH-PPV rings using mixed solvents at the air/water interface.

    Science.gov (United States)

    Chao, Kung-Po; Biswal, Sibani L

    2014-04-22

    Controlling the morphology of conjugated polymers has recently attracted considerable attention because of their applications in photovoltaic (PV) devices and organic light-emitting diodes (OLEDs). Here, we describe the self-assembly of a common conjugated polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), into ringlike structures via solvent evaporation on an air/water interface. The films are monitored using Brewster angle microscopy (BAM) and transferred onto a solid substrate by either the Langmuir-Blodgett (LB) or the Langmuir-Schaefer (LS) method and further characterized by atomic force microscopy (AFM). The morphology of the MEH-PPV thin film at the air/water interface can be controlled by the spreading solvent. By mixing solvents of varying spreading coefficients and evaporation rates, such as chloroform and chlorobenzene, MEH-PPV can be assembled into micrometer-sized ring structures. The optical properties of these MEH-PPV ring structures are also characterized. Lastly, MEH-PPV can be used as a soft template to organize microscale structures of nanoparticles.

  3. Structural varieties of selectively mixed G- and C-rich short DNA sequences studied with electrospray ionization mass spectrometry.

    Science.gov (United States)

    Cao, Yanwei; Gao, Shang; Li, Caijin; Yan, Yuting; Wang, Bing; Guo, Xinhua

    2016-10-01

    Short guanine(G)-repeat and cytosine(C)-repeat DNA strands can self-assemble to form four-stranded G-quadruplexes and i-motifs, respectively. Herein, G-rich and C-rich strands with non-G or non-C terminal bases and different lengths of G- or C-repeats are mixed selectively in pH 4.5 and 6.7 ammonium acetate buffer solutions and studied by electrospray ionization mass spectrometry (ESI-MS). Various strand associations corresponding to bi-, tri- and tetramolecular ions are observed in mass spectra, indicating that the formation of quadruplex structures is a random strand by strand association process. However, with increasing incubation time for the mixtures, initially associated hybrid tetramers will transform into self-assembled conformations, which is mainly driven by the structural stability. The melting temperature values of self-assembled quadruplexes suggest that the length of G-repeats or C-repeats shows more significant effect on the stability of quadruplex structures than that of terminal residues. Accordingly, we can obtain the self-associated tetrameric species generated from the mixtures of various homologous G- or C-strands efficiently by altering the length of G- or C-repeats. Our studies demonstrate that ESI-MS is a very direct, fast and sensitive tool to provide significant information on DNA strand associations and stoichiometric transitions, particularly for complex mixtures. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Effective body water and body mass changes during summer ultra-endurance road cycling.

    Science.gov (United States)

    Armstrong, Lawrence E; Johnson, Evan C; Ganio, Matthew S; Judelson, Daniel A; Vingren, Jakob L; Kupchak, Brian R; Kunces, Laura J; Muñoz, Colleen X; McKenzie, Amy L; Williamson, Keith H

    2015-01-01

    Because body mass change (ΔMb) does not represent all water losses and gains, the present field investigation determined if (a) ΔMb equalled the net effective body water change during ultra-endurance exercise and (b) ground speed and exercise duration influenced these variables. Thirty-two male cyclists (age range, 35-52 years) completed a 164-km event in a hot environment, were retrospectively triplet matched and placed into one of three groups based on exercise duration (4.8, 6.3, 9.6 h). Net effective body water loss was computed from measurements (body mass, total fluid intake and urine excreted) and calculations (water evolved and mass loss due to substrate oxidation, solid food mass and sweat loss), including (ΔEBWgly) and excluding (ΔEBW) water bound to glycogen. With all cyclists combined, the mean ΔMb (i.e. loss) was greater than that of ΔEBWgly by 1200 ± 200 g (P = 1.4 × 10(-18)), was similar to ΔEBW (difference, 0 ± 200 g; P = .21) and was strongly correlated with both (R(2) = .98). Analysis of equivalence indicated that ΔMb was not equivalent to ΔEBWgly, but was equivalent to ΔEBW. Due to measurement complexity, we concluded that (a) athletes will not calculate the effective body water calculations routinely and (b) body mass change remains a useful field-expedient estimate of net effective body water change.

  5. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (University of Zaragoza (Spain))

    2011-10-15

    the major geochemical processes controlling the behaviour of variables such as pH and Eh and, in general, all the parameters controlled by microbial or water-rock interaction processes. Thus, an integration of the mineralogical and microbiological data has also been performed. The other aim is to characterise the mixing processes that have affected the groundwaters over time. Thus, a statistical analysis has been performed with M3 in order to obtain a more quantitative approach to the mixing processes in the system, as well as to provide a mathematical basis to take into account all the variability of the system and to evaluate the reliability of the categorised groundwater types which are based on expert judgement (Nilsson et al. 2010). Therefore, this report should be considered as a supporting document to the final hydrogeochemical site description version 1.0 (Nilsson et al. 2011). Most of the main geochemical characters and trends observed in the SFR groundwaters are similar to those observed at Forsmark, especially if only groundwaters with marine contributions are compared. This applies to the carbonate, sulphate, silica and fluoride systems. No clear pH trend with depth has been found in these waters which may reflect the lateral heterogeneity of the groundwater system. The high and variable HCO{sub 3}{sup -} values found in groundwaters with a marine signature seem to be the result of the biological activity during infiltration of marine waters through seabed sediments. Calcite equilibrium is the main pH controlling process, and its presence has been detected at all depths. Marine waters are the main source of sulphur, and neither heterogeneous reactions with sulphate minerals (undersaturated, in the case of gypsum or in equilibrium in the case of barite), nor sulphate reducing microbial activity have played an important role on the control of dissolved sulphate concentrations (conditioned, therefore, mainly by mixing). Dissolved silica and fluoride

  6. Finescale Water-Mass Variability from ARGO Profiling Floats

    Science.gov (United States)

    2015-09-30

    researcher Dr. Cimarron Wortham arrived in September 2013 after completing a PhD under Carl Wunsch’s supervision at MIT to take the lead on the eddy... Schmitt 1990) or double-diffusively-driven thermohaline interleaving. The coarse temporal and vertical sampling of the data are unlikely to allow...equator. J. Phys. Oceanogr., 21, 933-938. Schmitt , R.W., 1990: On the density ratio balance in the Central Water. J. Phys. Oceanogr., 20, 900- 906

  7. Mass transfer and carbon isotope evolution in natural water systems

    Science.gov (United States)

    Wigley, T.M.L.; Plummer, L.N.; Pearson, F.J.

    1978-01-01

    This paper presents a theoretical treatment of the evolution of the carbon isotopes C13 and C14 in natural waters and in precipitates which derive from such waters. The effects of an arbitrary number of sources (such as dissolution of carbonate minerals and oxidation of organic material) and sinks (such as mineral precipitation, CO2 degassing and production of methane), and of equilibrium fractionation between solid, gas and aqueous phases are considered. The results are expressed as equations relating changes in isotopic composition to changes in conventional carbonate chemistry. One implication of the equations is that the isotopic composition of an aqueous phase may approach a limiting value whenever there are simultaneous inputs and outputs of carbonate. In order to unambiguously interpret isotopic data from carbonate precipitates and identify reactants and products in reacting natural waters, it is essential that isotopic changes are determined chiefly by reactant and product stoichiometry, independent of reaction path. We demonstrate that this is so by means of quantitative examples. The evolution equations are applied to: 1. (1) carbon-14 dating of groundwaters; 2. (2) interpretation of the isotopic composition of carbonate precipitates, carbonate cements and diagenetically altered carbonates; and 3. (3) the identification of chemical reaction stoichiometry. These applications are illustrated by examples which show the variation of ??C13 in solutions and in precipitates formed under a variety of conditions involving incongruent dissolution, CO2 degassing, methane production and mineral precipitation. ?? 1978.

  8. Effects of Flavour-Dependent qq Annihilation on the Mixing Angle of the Isoscalar Octet-Singlet and Schwinger's Nonet Mass Formula

    Institute of Scientific and Technical Information of China (English)

    LI De-Min; YU Hong; SHEN Qi-Xing

    2001-01-01

    By incorporating the flavour-dependent quark-antiquark annihilation amplitude into the mass-squared matrix describing the mixing of the isoscalar states of a meson nonet, the new version of Schwinger's nonet mass formula,N which holds with a high accuracy for the 0-+, 1--, 2++, 2-+ and 3-- nonets, is derived and the mixing angle of theisoscalar octet-singlet for these honets is obtained. In particular, the mixing angle of the isoscalar octet singlet for the pseudoscalar nonet is determined to take the value of-12.92°, which is in agreement with the value range fiom -13° to -17° deduced fiom a rather exhaustive and up-to-date analysis of data. It is also pointed out that the omission of the flavour-dependent qq annihilation effect might be a factor resulting in the invalidity of Schwinger's original honet mass formula for the pseudoscalar nonet.

  9. Influence of the Mixing State of tert- Butyl Alcohol-water Mixtures on the Conformation of Bovine Serum Albumin

    Institute of Scientific and Technical Information of China (English)

    MA,Lin; WANG,Xu; XU,Li; HE,Wei-Ren; WEI,Zhi-Qiang; LIN,Rui-Sen

    2008-01-01

    The hydrodynamic radii of bovine serum albumin (BSA) in TBA-water mixtures were determined by dynamic light scattering measurements and utilized to investigate the conformational change of BSA in TBA-water mixtures, together with the analysis of the fluorescence spectra and UV-vis absorption spectra of BSA. Meanwhile, static light scattering measurements were used to probe the mixing state of the binary mixtures of TBA-water and the ternary mixtures of BSA-TBA-water and its influence on the conformation of the protein. A close relationship between the mixing state of TBA-water mixtures and the conformation of BSA was observed. The mixing state of TBA-water mixture at a low concentration was characterized by the clathrate hydrate of TBA caged by water molecules and it was found that hydrophobic binding of TBA to nonpolar groups of BSA in general destabilized the native structure of the protein, however, addition of a small amount of TBA attenuated the hydrophobic interactions among nonpolar groups of the protein and promoted a more ordered conformation. The results clearly showed that clustering of TBA at a high concentration reduced the effectiveness on destabilization of the compact conformation of proteins.

  10. Enzymatic hydrolysis of penicillin in mixed ionic liquids/water two-phase system.

    Science.gov (United States)

    Jiang, Yangyang; Xia, Hansong; Guo, Chen; Mahmood, Iram; Liu, Huizhou

    2007-01-01

    In this paper, an integrated process involving the mixed ionic liquids/water two-phase system (MILWS) is proposed to improve the efficiency for enzymatic hydrolysis of penicillin G. First, hydrophilic [C4mim]BF4 (1-butyl-3-methylimidazolium tetrafluoraborate) and NaH2PO4 salt form an ionic liquids aqueous two-phase system (ILATPS), which could extract penicillin from its fermentation broth efficiently. Second, a hydrophobic [C4mim]PF6 (1-butyl-3-methylimidazolium hexafluoraphosphate) is introduced into the ionic liquids-rich phase of ILATPS containing penicillin and converses it into MILWS. Penicillin is hydrolyzed by penicillin acylase in the water phase of MILWS at pH 5. The byproduct phenylacetic acid (PAA) is partitioned into the ionic liquids mixture phase, while the intended product 6-aminopenicillanic acid (6-APA) is precipitated at this pH. In comparison with a similar butyl acetate/water system (BAWS) at pH 4, MILWS exhibits two advantages. (1) The selectivity between PAA and penicillin is greatly optimized at pH 5 by varying the mole ratio of [C4mim]PF6/[C4mim]BF4 in MILWS, whereas in BAWS the unalterable nature of the organic solvent restricts the optimized pH for maximum selectivity between PAA and penicillin at pH 4. (2) The pH for 6-APA precipitation in BAWS is 4, whereas it shifts to pH 5 in MILWS due to the complexation between negatively charged 6-APA and the cationic surface of the ionic liquids micelle. As a result, the removal of the two products from the enzyme sphere at relatively high pH is permitted in MILWS, which is beneficial for enzymatic activity and stability in comparison with the acidic pH 4 environment in BAWS.

  11. Characterization of oil sands process-affected waters by liquid chromatography orbitrap mass spectrometry.

    Science.gov (United States)

    Pereira, Alberto S; Bhattacharjee, Subir; Martin, Jonathan W

    2013-05-21

    Recovery of bitumen from oil sands in northern Alberta, Canada, occurs by surface mining or in situ thermal recovery, and both methods produce toxic oil sands process-affected water (OSPW). A new characterization strategy for surface mining OSPW (sm-OSPW) and in situ OSPW (is-OSPW) was achieved by combining liquid chromatography with orbitrap mass spectrometry (MS). In electrospray positive and negative ionization modes (ESI(+)/ESI(-)), mass spectral data were acquired with high resolving power (RP > 100,000-190,000) and mass accuracy (method should be further applied to environmental forensic analysis of water in the region.

  12. Radiation and Dufour Effects on Unsteady MHD Mixed Convective Flow in an Accelerated Vertical Wavy Plate with Varying Temperature and Mass Diffusion

    Directory of Open Access Journals (Sweden)

    Jagdish PRAKASH

    2014-01-01

    Full Text Available This paper studies flow, heat, and mass transfer characteristics of unsteady mixed convective magnetohydrodynamic (MHD flow of a heat absorbing fluid in an accelerated vertical wavy plate, subject to varying temperature and mass diffusion, with the influence of buoyancy, thermal radiation and Dufour effect. The momentum, energy and mass diffusion equations are coupled non-linear partial differential equations, which are solved by perturbation technique. The features of the fluid flow, heat and mass transfer characteristics are analyzed by plotting graphs, and the physical aspects are discussed in detail to interpret the effects of significant parameters of the problem.doi:10.14456/WJST.2014.69

  13. Circulation of water masses in the Baltic Proper revealed through iodine isotopes

    DEFF Research Database (Denmark)

    Yi, P.; Chen, X.G.; Aldahan, A.

    2013-01-01

    : (1) inflow water masses through the Drogden Sill that may reach as far as the SW of the Arkona Sea, (2) a portion of North Atlantic water in the bottom of Arkona basin, (3) cyclonic upwelling which breaks through the halocline in a pattern similar to the Baltic haline conveyor belt and (4) more...

  14. Water masses and general hydrography along the west coast of India during early March

    Digital Repository Service at National Institute of Oceanography (India)

    RameshBabu, V.; Varkey, M.J.; Das, V.K.; Gouveia, A.D.

    Structure of water masses along the west coast of India from Bombay to Trivandrum has been studied through vertical sections of temperature, salinity and density during 3-17 March 1977. The Arabian Sea high salinity water spreads south as a core...

  15. Effect of water storage on ultimate tensile strength and mass changes of universal adhesives.

    Science.gov (United States)

    Bahrololumi, Nazanin; Beglou, Amirreza; Najafi-Abrandabadi, Ahmad; Sadr, Alireza; Sheikh-Al-Eslamian, Seyedeh-Mahsa; Ghasemi, Amir

    2017-01-01

    The aim of the present study was to evaluate the influence of water storage on micro tensile strength (µTS) and mass changes (MC) of two universal adhesives. 10 disk-shaped specimens were prepared for each adhesive; Scotchbond Universal (SCU) All-Bond Universal (ABU) and Adper Single Bond 2 (SB2). At the baseline and after 1 day and 28 days of water storage, their mass were measured and compared to estimate water sorption and solubility. For µTS test, 20 dumbbell shaped specimens were also prepared for each adhesive in two subgroups of 1 day and 28 days water storage. MC was significantly lower for SCU and ABU than SB2 (P water; both universal adhesives showed less water sorption and higher values of µTS than the control group. Key words:Absorption, dental adhesives, dentin-bonding agents, solubility, tensile strength.

  16. Tree specific traits vs. stand level characteristics - assessing the source depths of plant water uptake in a mixed forest stand

    Science.gov (United States)

    Seeger, Stefan; Brinkmann, Nadine; Kahmen, Ansgar; Weiler, Markus

    2017-04-01

    Due to differences in fine root distributions, physiological root characteristics and plant plasticity, the spatial and temporal characteristics of plant water uptake are expected to vary between different tree species. This has implications on the overall water budget of a forest stand as well as on the drought sensitivity of particular trees. A four-year time series of climate data, soil moisture, and stable water isotopes in soil and tree xylem was used to investigate plant water uptake dynamics of four tree species (beech - Fagus sylvatica, spruce - Picea abies, ash - Fraxinus excelsior and maple - Acer pseudoplatanus) in a mixed forest stand. Modeling with a modified version of the soil hydrological model Hydrus-1D allowed us to simulate continuous time series of stable water isotopes in plant water uptake, which were compared to the measured values in tree xylem water and soil water. We found that different estimated species specific fine root distributions and root water uptake parameters lead to very similar simulated water balances and soil water isotope depth profiles for all four species. According to our simulations, differences in evaporative demand (i.e. LAI) had the biggest influence on water uptake and soil water distributions. Comparing the isotopic signatures of simulated root water uptake and measured xylem water, the simulations for beech were most suited to predict the observed signatures of all four species. This indicates that isolated, tree specific parametrized 1-D simulations are not suited to predict actual water uptake of different trees in a mixed stand. Due to overlapping root spaces dominant trees (in our case beeches with an LAI of around 5.5) may influence the soil water storage below accompanying trees (spruces, ashes and maples with LAIs between 1.8 and 3.1) in a degree that their actual water uptake cannot be predicted with 1-D simulations based on their smaller LAI values. Consequently, for a mixed forest stand the interplay of

  17. Mixing in Visakhapatnam harbour and nutrient inputs to nearshore waters, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    RamaRaju, V.S.; Sarma, V.V.; Raju, G.R.K.; Rao, V.S.

    The flushing time (t) and replacement time CD are computed for different seasons to understand mixing in Visakhapatnam harbour. Replacement times are higher than the flushing times indicating that the transverse mixing in the tidal flow...

  18. Mixing at double-Tee junctions with unequal pipe sizes in water distribution systems

    Data.gov (United States)

    U.S. Environmental Protection Agency — Pipe flow mixing with various solute concentrations and flow rates at pipe junctions is investigated. The degree of mixing affects the spread of contaminants in a...

  19. Experimental and Numerical Studies of Controlling Thermal Cracks in Mass Concrete Foundation by Circulating Water

    Directory of Open Access Journals (Sweden)

    Wenchao Liu

    2016-04-01

    Full Text Available This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China, as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and the atmospheric environment. The temperature gradient between the surface and the core of the mass concrete is controlled at a relatively stable state. Water collected from the well-points used for dewatering and from rainfall is used as the source for circulating water. Mass concrete of a foundation slab is experimentally investigated through field temperature monitoring. Numerical analyses are performed by developing a finite element model of the foundation with and without water circulation. The calculation parameters are proposed based on the experiment, and finite element analysis software MIDAS/CIVIL is used to calculate the 3D temperature field of the mass concrete during the entire process of heat of hydration. The numerical results are in good agreement with the measured results. The proposed method provides an alternative practical basis for preventing thermal cracks in mass concrete.

  20. Turbulent heat and mass transfers across a thermally stratified air-water interface

    Science.gov (United States)

    Papadimitrakis, Y. A.; Hsu, Y.-H. L.; Wu, J.

    1986-01-01

    Rates of heat and mass transfer across an air-water interface were measured in a wind-wave research facility, under various wind and thermal stability conditions (unless otherwise noted, mass refers to water vapor). Heat fluxes were obtained from both the eddy correlation and the profile method, under unstable, neutral, and stable conditions. Mass fluxes were obtained only under unstable stratification from the profile and global method. Under unstable conditions the turbulent Prandtl and Schmidt numbers remain fairly constant and equal to 0.74, whereas the rate of mass transfer varies linearly with bulk Richardson number. Under stable conditions the turbulent Prandtl number rises steadily to a value of 1.4 for a bulk Richardson number of about 0.016. Results of heat and mass transfer, expressed in the form of bulk aerodynamic coefficients with friction velocity as a parameter, are also compared with field data.

  1. Effect of liquid distribution on gas-water phase mass transfer in an unsaturated sand during infiltration

    Science.gov (United States)

    Imhoff, Paul T.; Jaffé, Peter R.

    1994-09-01

    Gas-water phase mass transfer was examined in a homogeneous sand with both the gas and water phase mobile: water was infiltrated from the top of the sand column while benzene-laden air flowed upward from the bottom. Mass-transfer limitations for this situation may be important for applications of bioventing, where water and nutrients are added at the ground surface simultaneously with induced air movement to carry oxygen and volatile organics to microbial populations. Gas- and water-phase samples indicate that gas-water phase mass transfer was sufficiently fast that equilibrium between gas and water phases was achieved at all sampling locations within the porous medium. Lower-bound estimates for the gas-water mass-transfer rate coefficient show that mass transfer was at least 10-40 times larger than predictions made from an empirical model developed for gas-water phase mass transfer in an identical porous medium. A water-phase tracer test demonstrates that water flow was much more uniform in this study than in those earlier experiments, which is a likely explanation for the differing rates of gas-water phase mass transfer. It is hypothesized that the liquid distribution in previous laboratory experiments was less uniform because of preferential flow paths due to wetting front instabilities. Gas-water phase mass-transfer rate coefficients reported in this investigation are for an ideal situation of uniform water infiltration: mass-transfer rates in field soils are expected to be significantly smaller.

  2. Effects of water-mass changes on Quaternary biostratigraphy, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Denne, R.A. (Exxon Co., USA, Houston, TX (United States)); Sen Gupta, B.K. (Louisiana State Univ., Baton Rouge (United States))

    1991-03-01

    The quantitative record of benthic foraminifera in 61 cores from the northwestern Gulf of Mexico slope (283-1,341 m; 90-95{degree}W) indicates a strong relationship between the distribution of benthic foraminifera and that of water masses during the last 15,000 years, producing potentially useful biostratigraphic datums. In the extreme case, the effect of water-mass changes may be reflected in the local stratigraphic limits of a species. More commonly, such changes may significantly affect abundance variations of species in the stratigraphic column. During the last deglaciation (13-11 Ka), several common species of the Subantarctic Intermediate Water (e.g., Bulimina alazanesis, Osangularia culter) reappeared in the gulf with the reentry of this water mass, whereas Valvulineria 'A' disappeared because of a drastic reduction in the production of the Glacial North Atlantic Intermediate Water. Thus, within the depth range of these species coeval oceanographic events produced a biostratigraphic datum that is isochronous throughout the gulf. At the same time, at a water depth of about 800 m, the relative abundances of Bolivina albatrossi, Bolivina ordinaria, and Epistominella exigua increased, while those of Gavelinopsis translucens, Neocrosbyia minuta, and 'Valvulineria opima' decreased. The data also show that numerous species, including some recognized depth indicators, underwent changes in their depth adaptations during the deglaciation because of shifts of particular water-mass boundaries; these changes have to be taken into account in paleobathymetric interpretations of species occurrences or abundances.

  3. Reverse electrodialysis : Performance of a stack with 50 cells on the mixing of sea and river water

    NARCIS (Netherlands)

    Veerman, J.; Saakes, M.; Metz, S. J.; Harmsen, G. J.

    2009-01-01

    The purpose of reverse electrodialysis (RED) is to produce electricity upon the mixing of two solutions. We studied the power density (W/m(2)) and the energy efficiency (the amount of energy produced from specified volumes of river and sea water in relation to the thermodynamic maximum). With a

  4. Reverse electrodialysis : Performance of a stack with 50 cells on the mixing of sea and river water

    NARCIS (Netherlands)

    Veerman, J.; Saakes, M.; Metz, S. J.; Harmsen, G. J.

    2009-01-01

    The purpose of reverse electrodialysis (RED) is to produce electricity upon the mixing of two solutions. We studied the power density (W/m(2)) and the energy efficiency (the amount of energy produced from specified volumes of river and sea water in relation to the thermodynamic maximum). With a stac

  5. Reverse electrodialysis : Performance of a stack with 50 cells on the mixing of sea and river water

    NARCIS (Netherlands)

    Veerman, J.; Saakes, M.; Metz, S. J.; Harmsen, G. J.

    2009-01-01

    The purpose of reverse electrodialysis (RED) is to produce electricity upon the mixing of two solutions. We studied the power density (W/m(2)) and the energy efficiency (the amount of energy produced from specified volumes of river and sea water in relation to the thermodynamic maximum). With a stac

  6. Urban water metabolism indicators derived from a water mass balance - Bridging the gap between visions and performance assessment of urban water resource management.

    Science.gov (United States)

    Renouf, M A; Serrao-Neumann, S; Kenway, S J; Morgan, E A; Low Choy, D

    2017-10-01

    Improving resource management in urban areas has been enshrined in visions for achieving sustainable urban areas, but to date it has been difficult to quantify performance indicators to help identify more sustainable outcomes, especially for water resources. In this work, we advance quantitative indicators for what we refer to as the 'metabolic' features of urban water management: those related to resource efficiency (for water and also water-related energy and nutrients), supply internalisation, urban hydrological performance, sustainable extraction, and recognition of the diverse functions of water. We derived indicators in consultation with stakeholders to bridge this gap between visions and performance indicators. This was done by first reviewing and categorising water-related resource management objectives for city-regions, and then deriving indicators that can gauge performance against them. The ability for these indicators to be quantified using data from an urban water mass balance was also examined. Indicators of water efficiency, supply internalisation, and hydrological performance (relative to a reference case) can be generated using existing urban water mass balance methods. In the future, indicators for water-related energy and nutrient efficiencies could be generated by overlaying the urban water balance with energy and nutrient data. Indicators of sustainable extraction and recognising diverse functions of water will require methods for defining sustainable extraction rates and a water functionality index. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. An argon–nitrogen–hydrogen mixed-gas plasma as a robust ionization source for inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Makonnen, Yoseif; Beauchemin, Diane, E-mail: diane.beauchemin@chem.queensu.ca

    2014-09-01

    Multivariate optimization of an argon–nitrogen–hydrogen mixed-gas plasma for minimum matrix effects, while maintaining analyte sensitivity as much as possible, was carried out in inductively coupled plasma mass spectrometry. In the presence of 0.1 M Na, the 33.9 ± 3.9% (n = 13 elements) analyte signal suppression on average observed in an all-argon plasma was alleviated with the optimized mixed-gas plasma, the average being − 4.0 ± 8.8%, with enhancement in several cases. An addition of 2.3% v/v N{sub 2} in the outer plasma gas, and 0.50% v/v H{sub 2} to the central channel, as a sheath around the nebulizer gas flow, was sufficient for this drastic increase in robustness. It also reduced the background from ArO{sup +} and Ar{sub 2}{sup +} as well as oxide levels by over an order of magnitude. On the other hand, the background from NO{sup +} and ArN{sup +} increased by up to an order of magnitude while the levels of doubly-charged ions increased to 7% (versus 2.7% in an argon plasma optimized for sensitivity). Furthermore, detection limits were generally degraded by 5 to 15 fold when using the mixed-gas plasma versus the argon plasma for matrix-free solution (although they were better for several elements in 0.1 M Na). Nonetheless, the drastically increased robustness allowed the direct quantitative multielement analysis of certified ore reference materials, as well as the determination of Mo and Cd in seawater, without using any matrix-matching or internal standardization. - Highlights: • Addition of N{sub 2} to the plasma gas and H{sub 2} as a sheath gas results in a very robust ICP. • ArO{sup +} and Ar{sub 2}{sup +} background and oxide levels are reduced by over an order of magnitude. • Multielement analysis of rock digests is possible with a simple external calibration. • No internal standardization or matrix-matching is required for accurate analysis. • Cd and Mo were accurately determined in undiluted seawater.

  8. Collection efficiency of the Soot-Particle Aerosol Mass Spectrometer (SP-AMS for internally mixed particulate black carbon

    Directory of Open Access Journals (Sweden)

    M. D. Willis

    2014-05-01

    Full Text Available The soot-particle aerosol mass spectrometer (SP-AMS uses an intra-cavity infrared laser to vaporize refractory black carbon (rBC containing particles, making the particle beam–laser beam overlap critical in determining the collection efficiency (CE for rBC and associated non-refractory particulate matter (NR-PM. This work evaluates the ability of the SP-AMS to quantify rBC and NR-PM mass in internally mixed particles with different thicknesses of organic coating. Using apparent relative ionization efficiencies for uncoated and thickly coated rBC particles, we report measurements of SP-AMS sensitivity to NR-PM and rBC, for Regal Black, the recommended particulate calibration material. Beam width probe (BWP measurements are used to illustrate an increase in sensitivity for highly coated particles due to narrowing of the particle beam, which enhances the CE of the SP-AMS by increasing the laser beam–particle beam overlap. Assuming complete overlap for thick coatings, we estimate CE for bare Regal Black particles of 0.6 ± 0.1, which suggests that previously measured SP-AMS sensitivities to Regal Black were underestimated by up to a factor of two. The efficacy of the BWP measurements is highlighted by studies at a busy road in downtown Toronto and at a non-roadside location, which show particle beam widths similar to, but greater than that of bare Regal Black and coated Regal Black, respectively. Further BWP measurements at field locations will help to constrain the range of CE for fresh and aged rBC-containing particles. The ability of the SP-AMS to quantitatively assess the composition of internally mixed particles is validated through measurements of laboratory-generated organic coated particles, which demonstrate that the SP-AMS can quantify rBC and NR-PM over a wide range of particle compositions and rBC core sizes.

  9. Collection efficiency of the soot-particle aerosol mass spectrometer (SP-AMS for internally mixed particulate black carbon

    Directory of Open Access Journals (Sweden)

    M. D. Willis

    2014-12-01

    Full Text Available The soot-particle aerosol mass spectrometer (SP-AMS uses an intra-cavity infrared laser to vaporize refractory black carbon (rBC containing particles, making the particle beam–laser beam overlap critical in determining the collection efficiency (CE for rBC and associated non-refractory particulate matter (NR-PM. This work evaluates the ability of the SP-AMS to quantify rBC and NR-PM mass in internally mixed particles with different thicknesses of organic coating. Using apparent relative ionization efficiencies for uncoated and thickly coated rBC particles, we report measurements of SP-AMS sensitivity to NR-PM and rBC, for Regal Black, the recommended particulate calibration material. Beam width probe (BWP measurements are used to illustrate an increase in sensitivity for highly coated particles due to narrowing of the particle beam, which enhances the CE of the SP-AMS by increasing the laser beam–particle beam overlap. Assuming complete overlap for thick coatings, we estimate CE for bare Regal Black particles of 0.6 ± 0.1, which suggests that previously measured SP-AMS sensitivities to Regal Black were underestimated by up to a factor of 2. The efficacy of the BWP measurements is highlighted by studies at a busy road in downtown Toronto and at a non-roadside location, which show particle beam widths similar to, but greater than that of bare Regal Black and coated Regal Black, respectively. Further BWP measurements at field locations will help to constrain the range of CE for fresh and aged rBC-containing particles. The ability of the SP-AMS to quantitatively assess the composition of internally mixed particles is validated through measurements of laboratory-generated organic coated particles, which demonstrate that the SP-AMS can quantify rBC and NR-PM over a wide range of particle compositions and rBC core sizes.

  10. Water gas shift reaction over Cu catalyst supported by mixed oxide materials for fuel cell application

    Directory of Open Access Journals (Sweden)

    Tepamatr Pannipa

    2016-01-01

    Full Text Available The water gas shift activities of Cu on ceria and Gd doped ceria have been studied for the further enhancement of hydrogen purity [1] after the steam reforming of ethanol. The catalytic properties of commercial catalysts were also studied to compare with the as-prepared catalysts. Copper-containing cerium oxide materials are shown in this work to be suitable for the high temperature. Copper-ceria is a stable high-temperature shift catalyst, unlike iron-chrome catalysts that deactivate severely in CO2-rich gases. We found that 5%Cu/10%GDC(D has much higher activity than other copper ceria based catalysts. The finely dispersed CuO species is favorable to the higher activity, which explained the activity enhancement of this catalyst. The kinetics of the WGS reaction over Cu catalysts supported by mixed oxide materials were measured in the temperature range 200-400 °C. An independence of the CO conversion rate on CO2 and H2 was found.

  11. SYNTHESIS AND CHARACTERIZATION OF CELLULOSE-SILICA COMPOSITE FIBER IN ETHANOL/WATER MIXED SOLVENTS

    Directory of Open Access Journals (Sweden)

    Ning Jia

    2011-04-01

    Full Text Available Cellulose-silica composite fiber samples have been successfully synthesized using cellulose solution, tetraethoxysilane, and NH3•H2O in ethanol/water mixed solvents at room temperature for 24 h. The cellulose solution was previously prepared by the dissolution of microcrystalline cellulose in a solvent mixture of N,N-dimethylacetamide (DMAc/lithium chloride (LiCl. The effect of the tetraethoxysilane concentration on the product was investigated. The products were characterized by X-ray powder diffraction (XRD, thermogravimetric analysis (TG, differential scanning calorimetric analysis (DSC, scanning electron microscopy (SEM, Fourier transform infrared spectrometry (FT-IR, energy-dispersive X-ray spectrum (EDS, and cross polarization magic angle spinning (CP/MAS solid state 13C-NMR. The morphology of the cellulose-silica composite fiber was investigated by SEM, while their composition was established from EDS measurements combined with the results of FT-IR spectral analysis and XRD patterns. The XRD, FT-IR and EDS results indicated that the obtained product was cellulose-silica composite fiber. The SEM micrographs showed that the silica particles were homogeneously dispersed in the cellulose fiber. The CP/MAS solid state 13C-NMR results indicated that the silica concentration had an influence on the crystallinity of the cellulose. This method is simple for preparation of cellulose-based composites.

  12. Inhibition of positronium formation by nitroso spin trap scavengers in methanol-water mixed solvents

    Energy Technology Data Exchange (ETDEWEB)

    Levay, Bela [Department of Nuclear Chemistry, Eoetvoes Lorand University, Budapest (Hungary)]. E-mail: levay@para.chem.elte.hu; Boros, Marton [Department of Nuclear Chemistry, Eoetvoes Lorand University, Budapest (Hungary)

    2004-10-25

    The positron annihilation lifetime spectroscopy (PALS) is used to study the effect of nitroso spin trap scavengers on the positronium (Ps) yields in methanol-water mixed solvents. Nitrosobenzene (NOB), N,N-dimethyl-4-nitroso-aniline (DMNA) and tert-nitroso-butane (tNOBu) are investigated. These compounds have been found to be good Ps inhibitors. The numerical values of the Ps inhibition coefficients ({sigma}) exhibit similar trend to those of the reaction rate constants of o-Ps (k{sub p}) and solvated electron (k{sub e}) for the same compounds and increase in the same order: tNOBuDMNANOB. Solvent composition dependence of {sigma} for both DMNA and NOB shows strong correlation with that of the reaction of es- with nitrobenzene, that is a scavenger similar to NOB. The Ps inhibition capacity of nitroso compounds decreases with increasing temperature reflecting that the activation energy of the Ps formation reaction is greater than that of the electron scavenging one.

  13. Water-Induced Decoupling of Tracer and Electrochemical Oxygen Exchange Kinetics on Mixed Conducting Electrodes

    Science.gov (United States)

    2016-01-01

    Isotope exchange depth profiling and electrochemical impedance spectroscopy are usually regarded as complementary tools for measuring the surface oxygen exchange activity of mixed conducting oxides, for example used in solid oxide fuel cell (SOFC) electrodes. Only very few studies compared electrical (kq) and tracer (k*) exchange coefficients of solid–gas interfaces measured under identical conditions. The 1:1 correlation between kq and k* often made is thus more an assumption than experimentally verified. In this study it is shown that the measured rates of electrical and tracer exchange of oxygen may strongly differ. Simultaneous acquisition of kq and k* on La0.6Sr0.4FeO3-δ and SrTi0.3Fe0.7O3-δ thin film electrodes revealed that k* > 100 kq in humid oxidizing (16O2 + H218O) and humid reducing (H2 + H218O) atmospheres. These results are explained by fast water adsorption and dissociation on surface oxygen vacancies, forming two surface hydroxyl groups. Hence, interpreting experimentally determined k* values in terms of electrochemically relevant oxygen exchange is not straightforward. PMID:27389420

  14. Large eddy simulation and PIV experiments of air-water mixing tanks

    Science.gov (United States)

    Zamankhan, Piroz

    2010-06-01

    The simulations and experiments of a turbulent bubbly flow are carried out in a cylindrical mixing vessel. Dynamics of the turbulent bubbly flow is visualized using a novel two-phase particle image velocimetry (PIV) with a combination of back lighting, digital masking and fluorescent tracer particles. Using an advanced technique, Mie's scattering at surfaces of bubbles is totally filtered out and, henceforth, images of tracer particles and of bubbles are obtained with high quality. In parallel to the comprehensive experimental studies, numerical results are obtained from large eddy simulations (LES) of the two-phase air-water mixer. The impeller-induced flow at the blade tip radius is modeled by using sliding mesh method. The results demonstrate the existence of large structures such as tip-vortex tips, and also some finer details. In addition, the stability of the jet is found to be connected with the fluctuations of the tip vortices whose dynamics are affected by the presence of bubbles. Numerical results are used to interpret the measurement data and to guide the refinement of consistent theoretical analyses. Such information is invaluable in the development of advanced theories capable of describing bubbly flows in the presence of complex liquid flow. This detailed information is of real significance in facilitating the design and scale-up of practical stirred tanks.

  15. Survey of Worldwide Light Water Reactor Experience with Mixed Uranium-Plutonium Oxide Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cowell, B.S.; Fisher, S.E.

    1999-02-01

    The US and the Former Soviet Union (FSU) have recently declared quantities of weapons materials, including weapons-grade (WG) plutonium, excess to strategic requirements. One of the leading candidates for the disposition of excess WG plutonium is irradiation in light water reactors (LWRs) as mixed uranium-plutonium oxide (MOX) fuel. A description of the MOX fuel fabrication techniques in worldwide use is presented. A comprehensive examination of the domestic MOX experience in US reactors obtained during the 1960s, 1970s, and early 1980s is also presented. This experience is described by manufacturer and is also categorized by the reactor facility that irradiated the MOX fuel. A limited summary of the international experience with MOX fuels is also presented. A review of MOX fuel and its performance is conducted in view of the special considerations associated with the disposition of WG plutonium. Based on the available information, it appears that adoption of foreign commercial MOX technology from one of the successful MOX fuel vendors will minimize the technical risks to the overall mission. The conclusion is made that the existing MOX fuel experience base suggests that disposition of excess weapons plutonium through irradiation in LWRs is a technically attractive option.

  16. Effect of Reynolds and Grashof numbers on mixed convection inside a lid-driven square cavity filled with water-Al2O3 nanofluid

    Science.gov (United States)

    Jaman, Md. Shah; Islam, Showmic; Saha, Sumon; Hasan, Mohammad Nasim; Islam, Md. Quamrul

    2016-07-01

    A numerical analysis is carried out to study the performance of steady laminar mixed convection flow inside a square lid-driven cavity filled with water-Al2O3 nanofluid. The top wall of the cavity is moving at a constant velocity and is heated by an isothermal heat source. Two-dimensional Navier-stokes equations along with the energy equations are solved using Galerkin finite element method. Results are obtained for a range of Reynolds and Grashof numbers by considering with and without the presence of nanoparticles. The parametric studies for a wide range of governing parameters in case of pure mixed convective flow show significant features of the present problem in terms of streamline and isotherm contours, average Nusselt number and average temperature profiles. The computational results indicate that the heat transfer coeffcient is strongly influenced by the above governing parameters at the pure mixed convection regime.

  17. Experimental study on pressure and temperature distributions for low mass flux steam jet in subcooled water

    Institute of Scientific and Technical Information of China (English)

    YAN JunJie; WU XinZhuang; CHONG DaoTong

    2009-01-01

    A low mass flux steam jet in subcooled water was experimentally investigated. The transition of flow pattern from stable jet to condensation oscillation was observed at relatively high water temperature. The axial total pressures, the axial and radial temperature distributions were measured in the jet region. The results indicated that the pressure and temperature distributions were mainly influenced by the water temperature. The correlations corrected with water temperature were given to predict the dimen-sionless axial pressure peak distance and axial temperature distributions in the jet region, the results showed s good agreement between the predictions and experiments. Moreover, the self-similarity property of the radial temperature was obtained, which agreed well with Gauss distribution. In present work, all the dimensionless properties were mainly dependent on the water temperature but weakly on the nozzle size under a certain steam mass flux.

  18. Water-mass evolution in the Cretaceous Western Interior Seaway of North America and equatorial Atlantic

    Directory of Open Access Journals (Sweden)

    J. S. Eldrett

    2017-07-01

    Full Text Available The Late Cretaceous Epoch was characterized by major global perturbations in the carbon cycle, the most prominent occurring near the Cenomanian–Turonian (CT transition marked by Oceanic Anoxic Event 2 (OAE-2 at 94.9–93.7 Ma. The Cretaceous Western Interior Seaway (KWIS was one of several epicontinental seas in which a complex water-mass evolution was recorded in widespread sedimentary successions. This contribution integrates new data on the main components of organic matter, geochemistry, and stable isotopes along a north–south transect from the KWIS to the equatorial western Atlantic and Southern Ocean. In particular, cored sedimentary rocks from the Eagle Ford Group of west Texas (∼ 90–98 Ma demonstrate subtle temporal and spatial variations in palaeoenvironmental conditions and provide an important geographic constraint for interpreting water-mass evolution. High-latitude (boreal–austral, equatorial Atlantic Tethyan and locally sourced Western Interior Seaway water masses are distinguished by distinct palynological assemblages and geochemical signatures. The northward migration of an equatorial Atlantic Tethyan water mass into the KWIS occurred during the early–middle Cenomanian (98–95 Ma followed by a major re-organization during the latest Cenomanian–Turonian (95–94 Ma as a full connection with a northerly boreal water mass was established during peak transgression. This oceanographic change promoted de-stratification of the water column and improved oxygenation throughout the KWIS and as far south as the Demerara Rise off Suriname. In addition, the recorded decline in redox-sensitive trace metals during the onset of OAE-2 likely reflects a genuine oxygenation event related to open water-mass exchange and may have been complicated by variable contribution of organic matter from different sources (e.g. refractory/terrigenous material, requiring further investigation.

  19. Water-mass evolution in the Cretaceous Western Interior Seaway of North America and equatorial Atlantic

    Science.gov (United States)

    Eldrett, James S.; Dodsworth, Paul; Bergman, Steven C.; Wright, Milly; Minisini, Daniel

    2017-07-01

    The Late Cretaceous Epoch was characterized by major global perturbations in the carbon cycle, the most prominent occurring near the Cenomanian-Turonian (CT) transition marked by Oceanic Anoxic Event 2 (OAE-2) at 94.9-93.7 Ma. The Cretaceous Western Interior Seaway (KWIS) was one of several epicontinental seas in which a complex water-mass evolution was recorded in widespread sedimentary successions. This contribution integrates new data on the main components of organic matter, geochemistry, and stable isotopes along a north-south transect from the KWIS to the equatorial western Atlantic and Southern Ocean. In particular, cored sedimentary rocks from the Eagle Ford Group of west Texas (˜ 90-98 Ma) demonstrate subtle temporal and spatial variations in palaeoenvironmental conditions and provide an important geographic constraint for interpreting water-mass evolution. High-latitude (boreal-austral), equatorial Atlantic Tethyan and locally sourced Western Interior Seaway water masses are distinguished by distinct palynological assemblages and geochemical signatures. The northward migration of an equatorial Atlantic Tethyan water mass into the KWIS occurred during the early-middle Cenomanian (98-95 Ma) followed by a major re-organization during the latest Cenomanian-Turonian (95-94 Ma) as a full connection with a northerly boreal water mass was established during peak transgression. This oceanographic change promoted de-stratification of the water column and improved oxygenation throughout the KWIS and as far south as the Demerara Rise off Suriname. In addition, the recorded decline in redox-sensitive trace metals during the onset of OAE-2 likely reflects a genuine oxygenation event related to open water-mass exchange and may have been complicated by variable contribution of organic matter from different sources (e.g. refractory/terrigenous material), requiring further investigation.

  20. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2008-08-15

    in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. Several groups within ChemNet were involved and the evaluation was conducted independently using different approaches ranging from expert knowledge to geochemical and mathematical modelling including transport modelling. During regular ChemNet meetings the results have been presented and discussed. This report presents the modelling work performed by the University of Zaragoza group as part of the work planned for Forsmark during stages 2.2 and 2.3. The chemical characteristics of the groundwaters in the Forsmark and Laxemar areas are the result of a complex mixing process driven by the input of different recharge waters since the last glaciation. The successive penetration at different depths of dilute glacial melt-waters, Littorina Sea waters and dilute meteoric waters has triggered complex density and hydraulically driven flows that have mixed them with long residence time, highly saline waters present in the fractures and in the rock matrix. A general description of the main characteristics and processes controlling the hydrogeochemical evolution with depth in the Forsmark groundwater system is presented in this report: The hydrochemical characteristics and evolution of the Near surface waters (up to 20 m depth) is mainly determined by weathering reactions and especially affected by the presence of limestones. The biogenic CO{sub 2} input (derived from decay of organic matter and root respiration) and the associated weathering of carbonates control the pH and the concentrations of Ca and HCO{sub 3}- in the near-surface environment. Current seasonal variability of CO{sub 2} input produces variable but high calcium and bicarbonate contents in the Forsmark near-surface waters: up to 240 mg/L Ca and 150 to

  1. Size-selected black carbon mass distributions and mixing state in polluted and clean environments of northern India

    Science.gov (United States)

    Raatikainen, Tomi; Brus, David; Hooda, Rakesh K.; Hyvärinen, Antti-Pekka; Asmi, Eija; Sharma, Ved P.; Arola, Antti; Lihavainen, Heikki

    2017-01-01

    We have measured black carbon properties by using a size-selected single-particle soot photometer (SP2). The measurements were conducted in northern India at two sites: Gual Pahari is located at the Indo-Gangetic Plain (IGP) and Mukteshwar at the Himalayan foothills. Northern India is known as one of the absorbing aerosol hot spots, but detailed information about absorbing aerosol mixing state is still largely missing. Previous equivalent black carbon (eBC) mass concentration measurements are available for this region, and these are consistent with our observations showing that refractory black carbon (rBC) concentrations are about 10 times higher in Gual Pahari than those at Mukteshwar. Also, the number fraction of rBC-containing particles is higher in Gual Pahari, but individual rBC-containing particles and their size distributions are fairly similar. These findings indicate that particles at both sites have similar local and regional emission sources, but aerosols are also transported from the main source regions (IGP) to the less polluted regions (Himalayan foothills). Detailed examination of the rBC-containing particle properties revealed that they are most likely irregular particles such as fractal aggregates, but the exact structure remains unknown.

  2. Heat capacity and density of potassium iodide solutions in mixed N-methylpyrrolidone-water solvent at 298.15 K

    Science.gov (United States)

    Novikov, A. N.

    2014-10-01

    The heat capacity and density of potassium iodide solutions in a mixed N-methylpyrrolidone (MP)-water solvent with a low content of the organic component are measured via calorimetry and densimetry at 298.15 K. Standard partial molal heat capacities and volumes of potassium iodide in MP-water mixtures are calculated. Standard heat capacities and volumes of potassium and iodide ions are determined. The character of the changes in heat capacity and volume are discussed on the basis of calculating additivity coefficients δ c and δ v upon the mixing of isomolal binary solutions KI-MP and KI-water, depending on the composition of the MP-H2O mixture and the concentration of the electrolyte.

  3. Numerical Investigations of Mixed Convection of Incompressible Viscous Fluid in LNG Storage with a Various Locations of Input and Output Mass

    Directory of Open Access Journals (Sweden)

    Sklyarenko Kristina A.

    2015-01-01

    Full Text Available The article shows the results of mathematical simulation of mixed convection in the low-temperature storage of liquefied natural gas with a regenerative cooling. The regimes of mixed convection in a closed area with the different arrangement of the input and output sections of the masses are investigated. Two-dimensional nonstationary problem in the model of the Navier-Stokes in dimensionless variables “vorticity - stream function - temperature” was examined. Are obtained distributions of the hydrodynamic parameters and temperatures, characteristic basic laws governing the processes being investigated. Detailed circulating currents and carried out analysis of the mechanism of vortices formation and the temperature distribution in the solution for mixed convection mode with low Reynolds and Grashof numbers (Gr = 106, 100 mass sections and input stream velocity on the structure of liquid flow and temperature in the low temperature LNG storage tanks.

  4. Onset of transition from laminar to chaos in MHD mixed convection of a lid-driven trapezoidal cavity filled with Cu-water nanofluid

    Energy Technology Data Exchange (ETDEWEB)

    Azam, Mohammad, E-mail: azam09mebuet@gmail.com; Hasanuzzaman, Md., E-mail: hasanuzzaman138@gmail.com; Saha, Sumon, E-mail: sumonsaha@me.buet.ac.bd [Department of Mechanical Engineering, Bangladesh University of Engineering and Technology, Dhaka 1000 (Bangladesh)

    2016-07-12

    The present study investigates the thermal mixing scenarios of steady magneto-hydrodynamic (MHD) mixed convection in a two-dimensional lid-driven trapezoidal cavity filled with Cu-water nanofluid. The top wall of the cavity slides with a uniform velocity from left to right direction, while the other walls are fixed. The bottom wall is kept with a constant higher temperature than the top one. The governing mass, momentum and energy equations are expressed in non-dimensional forms and Galerkin finite element method has been employed to solve these equations. Special attention is paid on investigating the onset of transition from laminar to chaos at pure mixed convection case. Hence, the computations are carried out for a wide range of Reynolds numbers (Re = 0.1 − 400) and Grashof numbers (Gr = 10{sup −2} − 1.6 × 10{sup 5}) at unity Richardson number and fixed Hartmann number (Ha = 10). The variation of average Nusselt number of the bottom heated wall indicates the influence of governing parameters (Re and Gr) on heat transfer characteristics. The results are presented and explained through the visualisation of isotherms, streamlines and heatlines.

  5. Onset of transition from laminar to chaos in MHD mixed convection of a lid-driven trapezoidal cavity filled with Cu-water nanofluid

    Science.gov (United States)

    Azam, Mohammad; Hasanuzzaman, Md.; Saha, Sumon

    2016-07-01

    The present study investigates the thermal mixing scenarios of steady magneto-hydrodynamic (MHD) mixed convection in a two-dimensional lid-driven trapezoidal cavity filled with Cu-water nanofluid. The top wall of the cavity slides with a uniform velocity from left to right direction, while the other walls are fixed. The bottom wall is kept with a constant higher temperature than the top one. The governing mass, momentum and energy equations are expressed in non-dimensional forms and Galerkin finite element method has been employed to solve these equations. Special attention is paid on investigating the onset of transition from laminar to chaos at pure mixed convection case. Hence, the computations are carried out for a wide range of Reynolds numbers (Re = 0.1 - 400) and Grashof numbers (Gr = 10-2 - 1.6 × 105) at unity Richardson number and fixed Hartmann number (Ha = 10). The variation of average Nusselt number of the bottom heated wall indicates the influence of governing parameters (Re and Gr) on heat transfer characteristics. The results are presented and explained through the visualisation of isotherms, streamlines and heatlines.

  6. A dilution technique for the direct measurement of viral production: a comparison in stratified and tidally mixed coastal waters.

    Science.gov (United States)

    Wilhelm, S W; Brigden, S M; Suttle, C A

    2002-01-01

    The abundance of heterotrophic bacteria and viruses, as well as rates of viral production and virus-mediated mortality, were measured in Discovery Passage and the Strait of Georgia (British Columbia, Canada) along a gradient of tidal mixing ranging from well mixed to stratified. The abundances of bacteria and viruses were approximately 10(6) and 10(7) mL(-1), respectively, independent of mixing regime. Viral production estimates, monitored by a dilution technique, demonstrated that new viruses were produced at rates of 10(6) and 10(7) mL(-1)h(-1) across the different mixing regimes. Using an estimated burst size of 50 viruses per lytic event, ca. 19 to 27% of the standing stock of bacteria at the stratified stations and 46 to 137% at the deep-mixed stations were removed by viruses. The results suggest that mixing of stratified waters during tidal exchange enhances virus-mediated bacterial lysis. Consequently, viral lysis recycled a greater proportion of the organic carbon required for bacterial growth under non-steady-state compared to steady-state conditions.

  7. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (University of Zaragoza (Spain))

    2011-10-15

    the major geochemical processes controlling the behaviour of variables such as pH and Eh and, in general, all the parameters controlled by microbial or water-rock interaction processes. Thus, an integration of the mineralogical and microbiological data has also been performed. The other aim is to characterise the mixing processes that have affected the groundwaters over time. Thus, a statistical analysis has been performed with M3 in order to obtain a more quantitative approach to the mixing processes in the system, as well as to provide a mathematical basis to take into account all the variability of the system and to evaluate the reliability of the categorised groundwater types which are based on expert judgement (Nilsson et al. 2010). Therefore, this report should be considered as a supporting document to the final hydrogeochemical site description version 1.0 (Nilsson et al. 2011). Most of the main geochemical characters and trends observed in the SFR groundwaters are similar to those observed at Forsmark, especially if only groundwaters with marine contributions are compared. This applies to the carbonate, sulphate, silica and fluoride systems. No clear pH trend with depth has been found in these waters which may reflect the lateral heterogeneity of the groundwater system. The high and variable HCO{sub 3}{sup -} values found in groundwaters with a marine signature seem to be the result of the biological activity during infiltration of marine waters through seabed sediments. Calcite equilibrium is the main pH controlling process, and its presence has been detected at all depths. Marine waters are the main source of sulphur, and neither heterogeneous reactions with sulphate minerals (undersaturated, in the case of gypsum or in equilibrium in the case of barite), nor sulphate reducing microbial activity have played an important role on the control of dissolved sulphate concentrations (conditioned, therefore, mainly by mixing). Dissolved silica and fluoride

  8. Thermocline circulation and ventilation of the East/Japan Sea, part I: Water-mass characteristics and transports

    Science.gov (United States)

    You, Yuzhu; Chang, Kyung-Il; Yun, Jae-Yul; Kim, Kyung-Ryul

    2010-07-01

    The East/Japan Sea (EJS) has unique water-mass characteristics in the western Pacific marginal seas due to limited exchange with the open North Pacific. The major inflow of source water mass is North Pacific Subtropical Water (NPSW) carried by the Kuroshio branching and Tsushima Current. The locally formed cold/fresh waters from the Tatar Strait and Russia coast by winter convection mix with NPSW contributing to water-mass transformation, especially during winter when upper isopycnal surfaces outcrop and thermocline is ventilated. The geographic limit of the Korea/Tsushima Strait (KTS) with a sill depth of about 120-140 dbar confines the inflow of lower NPSW, and so the EJS thermocline layer is somewhat truncated with a rather thin layer for about 100 dbar. This study uses high resolution conductivity-temperature-depth (CTD) and Argo data with a third decimal or higher accuracy for temperature and salinity obtained mainly by Research Institute of Oceanography, Seoul National University through domestic and international collaboration with several Korean ocean research institutes and Russia and USA partners since early 1990s. The basin covered data were divided into summer and winter half-year representing seasonal difference since most CTD surveys were conducted purposely in summer and winter. Analysis is made for the upper layer, about 50-70 dbar, from the surface to the upper main thermocline and the thermocline layer down to about 150-180 dbar south of the subpolar front (SPF). The lower thermocline is defined slightly below the sill depth of the KTS, considering the deepening of NPSW after passing through the KTS. The thermocline layer is encompassed by three selected neutral density surfaces σN=25.8, 26.4 and 27.0 with a distance of about 40 dbar between two neighboring surfaces. The core of thermocline is followed by the σN=25.8 surface characterized by a salinity maximum and a minimum of potential vorticity. Winter convection is discussed and compared with

  9. Determination of membrane degradation products in the product water of polymer electrolyte membrane fuel cells using liquid chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zedda, Marco

    2011-05-12

    The predominant long term failure of polymer electrolyte membranes (PEM) is caused by hydroxyl radicals generated during fuel cell operation. These radicals attack the polymer, leading to chain scission, unzipping and consequently to membrane decomposition products. The present work has investigated decomposition products of novel sulfonated aromatic hydrocarbon membranes on the basis of a product water analysis. Degradation products from the investigated membrane type and the possibility to detect these compounds in the product water for diagnostic purposes have not been discovered yet. This thesis demonstrates the potential of solid phase extraction and liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) for the extraction, separation, characterization, identification and quantification of membrane degradation products in the product water of fuel cells. For this purpose, several polar aromatic hydrocarbons with different functional groups were selected as model compounds for the development of reliable extraction, separation and detection methods. The results of this thesis have shown that mixed mode sorbent materials with both weak anion exchange and reversed phase retention properties are well suited for reproducible extraction of both molecules and ions from the product water. The chromatographic separation of various polar aromatic hydrocarbons was achieved by means of phase optimized liquid chromatography using a solvent gradient and on a C18 stationary phase. Sensitive and selective detection of model compounds could be successfully demonstrated by the analysis of the product water using tandem mass spectrometry. The application of a hybrid mass spectrometer (Q Trap) for the characterization of unknown polar aromatic hydrocarbons has led to the identification and confirmation of 4-hydroxybenzoic acid in the product water. In addition, 4-HBA could be verified as a degradation product resulting from PEM decomposition by hydroxyl radicals using an

  10. Carbonate system in the water masses of the Southeast Atlantic sector of the Southern Ocean during February and March 2008

    Directory of Open Access Journals (Sweden)

    M. González-Dávila

    2011-05-01

    Full Text Available Carbonate system variables were measured in the South Atlantic sector of the Southern Ocean along a transect from South Africa to the southern limit of the Antarctic Circumpolar Current (ACC from February to March 2008. Eddies detached from the retroflection of the Agulhas Current increased the gradients observed along the fronts. Minima in the fugacity of CO2, fCO2, and maxima in pH on either side of the frontal zone were observed, noting that within the frontal zone fCO2 reached maximum values and pH was at a minimum.

    Vertical distributions of water masses were described by their carbonate system properties and their relationship to CFC concentrations. Upper Circumpolar Deep Water (UCDW and Lower Circumpolar Deep Water (LCDW offered pHT,25 values of 7.56 and 7.61, respectively. The UCDW also had higher concentrations of CFC-12 (>0.2 pmol kg−1 as compared to deeper waters, revealing that UCDW was mixed with recently ventilated waters. Calcite and aragonite saturation states (Ω were also affected by the presence of these two water masses with high carbonate concentrations. The aragonite saturation horizon was observed at 1000 m in the subtropical area and north of the Subantarctic Front. At the position of the Polar Front, and under the influence of UCDW and LCDW, the aragonite saturation horizon deepened from 800 m to 1500 m at 50.37° S, and reached 700 m south of 57.5° S. High latitudes proved to be the most sensitive areas to predicted anthropogenic carbon increase. Buffer coefficients related to changes in [CO2], [H+] and Ω with changes in dissolved inorganic carbon (CT and total alkalinity (AT offered minima values in the Antarctic Intermediate Water and UCDW layers. These coefficients suggest that a small increase in CT will sharply decrease the status of pH and carbonate saturation

  11. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides ((U, Pu)O2)

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides, (U, Pu)O2, powders and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Uranium in the Presence of Pu by Potentiometric Titration Plutonium by Controlled-Potential Coulometry Plutonium by Amperometric Titration with Iron (II) Nitrogen by Distillation Spectrophotometry Using Nessler Reagent 7 to 14 Carbon (Total) by Direct Combustion-Thermal Conductivity 15 to 26 Total Chlorine and Fluorine by Pyrohydrolysis 27 to 34 Sulfur by Distillation-Spectrophotometry 35 to 43 Moisture by the Coulometric, Electrolytic Moisture Analyzer 44 to 51 Isotopic Composition by Mass Spectrometry Rare Earths by Copper Spark Spectroscopy 52 to 59 Trace Impurities by Carrier Distillation Spectroscopy 60 to 69 Impurities by Spark-Source Mass Spectrography 70 to 76 Total Gas in Reactor-Grade Mixed Dioxide P...

  12. Tensiometry and dilational rheology of mixed β-lactoglobulin/ionic surfactant adsorption layers at water/air and water/hexane interfaces.

    Science.gov (United States)

    Dan, Abhijit; Gochev, Georgi; Miller, Reinhard

    2015-07-01

    Oscillating drop tensiometry was applied to study adsorbed interfacial layers at water/air and water/hexane interfaces formed from mixed solutions of β-lactoglobulin (BLG, 1 μM in 10 mM buffer, pH 7 - negative net charge) and the anionic surfactant SDS or the cationic DoTAB. The interfacial pressure Π and the dilational viscoelasticity modulus |E| of the mixed layers were measured for mixtures of varying surfactant concentrations. The double capillary technique was employed which enables exchange of the protein solution in the drop bulk by surfactant solution (sequential adsorption) or by pure buffer (washing out). The first protocol allows probing the influence of the surfactant on a pre-adsorbed protein layer thus studying the protein/surfactant interactions at the interface. The second protocol gives access to the residual values of Π and |E| measured after the washing out procedure thus bringing information about the process of protein desorption. The DoTAB/BLG complexes exhibit higher surface activity and higher resistance to desorption in comparison with those for the SDS/BLG complexes due to hydrophobization via electrostatic binding of surfactant molecules. The neutral DoTAB/BLG complexes achieve maximum elastic response of the mixed layer. Mixed BLG/surfactant layers at the water/oil interface are found to reach higher surface pressure and lower maximum dilational elasticity than those at the water/air surface. The sequential adsorption mode experiments and the desorption study reveal that binding of DoTAB to pre-adsorbed BLG globules is somehow restricted at the water/air surface in comparison with the case of complex formation in the solution bulk and subsequently adsorbed at the water/air surface. Maximum elasticity is achieved with washed out layers obtained after simultaneous adsorption, i.e. isolation of the most surface active DoTAB/BLG complex. These specific effects are much less pronounced at the W/H interface.

  13. Diffusive-dispersive mass transfer in the capillary fringe: Impact of water table fluctuations and heterogeneities

    DEFF Research Database (Denmark)

    Grathwohl, Peter; Haberer, Cristina; Ye, Yu;

    Diffusive–dispersive mass transfer in the capillary fringe is important for many groundwater quality issues such as transfer of volatile compounds into (and out of) the groundwater, the supply of oxygen for aerobic degradation of hydrocarbons as well as for precipitation of minerals (e.g. iron...... hydroxides). 2D-laboratory scale experiments were used to investigate the transfer of oxygen into groundwater under non-reactive and reactive conditions, at steady state and with water table fluctuations. Results show that transfer of oxygen is limited by transverse dispersion in the capillary fringe...... and the dispersion coefficients are the same as below the water table. Water table fluctuations cause temporarily increased fluxes of oxygen into groundwater during draining conditions and entrapped air after water table rise. High-permeability inclusions in the capillary fringe enhance mass transfer of oxygen...

  14. Integrated Water Gas Shift Membrane Reactors Utilizing Novel, Non Precious Metal Mixed Matrix Membrane

    Energy Technology Data Exchange (ETDEWEB)

    Ferraris, John

    2013-09-30

    Nanoparticles of zeolitic imidazolate frameworks and other related hybrid materials were prepared by modifying published synthesis procedures by introducing bases, changing stoichiometric ratios, or adjusting reaction conditions. These materials were stable at temperatures >300 °C and were compatible with the polymer matrices used to prepare mixed- matrix membranes (MMMs). MMMs tested at 300 °C exhibited a >30 fold increase in permeability, compared to those measured at 35 °C, while maintaining H{sub 2}/CO{sub 2} selectivity. Measurements at high pressure (up to 30 atm) and high temperature (up to 300 °C) resulted in an increase in gas flux across the membrane with retention of selectivity. No variations in permeability were observed at high pressures at either 35 or 300 °C. CO{sub 2}-induced plasticization was not observed for Matrimid®, VTEC, and PBI polymers or their MMMs at 30 atm and 300 °C. Membrane surface modification by cross-linking with ethanol diamine resulted in an increase in H{sub 2}/CO{sub 2} selectivity at 35 °C. Spectrometric analysis showed that the cross-linking was effective to temperatures <150 °C. At higher temperatures, the cross-linked membranes exhibit a H{sub 2}/CO{sub 2} selectivity similar to the uncross-linked polymer. Performance of the polybenzimidazole (PBI) hollow fibers prepared at Santa Fe Science and Technology (SFST, Inc.) showed increased flux o to a flat PBI membrane. A water-gas shift reactor has been built and currently being optimized for testing under DOE conditions.

  15. Imaging of oil layers, curvature and contact angle in a mixed-wet and a water-wet carbonate rock

    Science.gov (United States)

    Singh, Kamaljit; Bijeljic, Branko; Blunt, Martin J.

    2016-03-01

    We have investigated the effect of wettability of carbonate rocks on the morphologies of remaining oil after sequential oil and brine injection in a capillary-dominated flow regime at elevated pressure. The wettability of Ketton limestone was altered in situ using an oil phase doped with fatty acid which produced mixed-wet conditions (the contact angle where oil contacted the solid surface, measured directly from the images, θ=180°, while brine-filled regions remained water-wet), whereas the untreated rock (without doped oil) was weakly water-wet (θ=47 ± 9°). Using X-ray micro-tomography, we show that the brine displaces oil in larger pores during brine injection in the mixed-wet system, leaving oil layers in the pore corners or sandwiched between two brine interfaces. These oil layers, with an average thickness of 47 ± 17 µm, may provide a conductive flow path for slow oil drainage. In contrast, the oil fragments into isolated oil clusters/ganglia during brine injection under water-wet conditions. Although the remaining oil saturation in a water-wet system is about a factor of two larger than that obtained in the mixed-wet rock, the measured brine-oil interfacial area of the disconnected ganglia is a factor of three smaller than that of oil layers.

  16. Retrieval of water vapor mixing ratio from a multiple channel Raman-scatter lidar using an optimal estimation method.

    Science.gov (United States)

    Sica, R J; Haefele, A

    2016-02-01

    Lidar measurements of the atmospheric water vapor mixing ratio provide an excellent complement to radiosoundings and passive, ground-based remote sensors. Lidars are now routinely used that can make high spatial-temporal resolution measurements of water vapor from the surface to the stratosphere. Many of these systems can operate during the day and night, with operation only limited by clouds thick enough to significantly attenuate the laser beam. To enhance the value of these measurements for weather and climate studies, this paper presents an optimal estimation method (OEM) to retrieve the water vapor mixing ratio, aerosol optical depth profile, Ångstrom exponent, lidar constants, detector dead times, and measurement backgrounds from multichannel vibrational Raman-scatter lidars. The OEM retrieval provides the systematic uncertainties due to the overlap function, calibration factor, air density and Rayleigh-scatter cross sections, in addition to the random uncertainties of the retrieval due to measurement noise. The OEM also gives the vertical resolution of the retrieval as a function of height, as well as the height to which the contribution of the a priori is small. The OEM is applied to measurements made by the Meteoswiss Raman Lidar for Meteorological Observations (RALMO) in the day and night for clear and cloudy conditions. The retrieved water vapor mixing ratio is in excellent agreement with both the traditional lidar retrieval method and coincident radiosoundings.

  17. Mixing whey and soy proteins: Consequences for the gel mechanical response and water holding

    NARCIS (Netherlands)

    Jose, J.; Pouvreau, L.A.M.; Martin, Anneke

    2016-01-01

    To design food products based on mixtures of proteins from animal and plant sources, understanding of how the structural and mechanical properties of mixed protein systems can benefit from selectively mixing is essential. Heat-induced gels were prepared from mixtures of whey proteins (WP) and soy pr

  18. Mixing behaviour of a zero-developed dough compared to a flour-water mixture

    NARCIS (Netherlands)

    Peighambardoust, S.H.; Goot, A.J. van der; Boom, R.M.; Hamer, R.J.

    2006-01-01

    The Z-blade mixing behaviour of zero-developed (ZD) doughs from the flours of two wheat cultivars of different gluten strength was compared to that of conventionally mixed dough made from the same flours. In farinograph experiments, use of ZD dough led to shorter development time (with less energy

  19. Mesoscale variability of water masses in the Arabian Sea as revealed by ARGO floats

    Directory of Open Access Journals (Sweden)

    X. Carton

    2011-06-01

    Full Text Available By analysing ARGO float data over the last four years, some aspects of the mesoscale variability of water masses in the Arabian Sea are described.

    The Red Sea Water outflow is strong in the Southwestern Gulf of Aden, in particular when a cyclonic gyre predominates in this region. Salinities of 36.5 and temperatures of 16 °C are found there between 600 and 1000 m depths. The Red Sea Water is more dilute in the eastern part of the Gulf, and fragments of this water mass can be advected offshore across the gulf or towards its northern coast by the regional gyres. The Red Sea Water outflow is also detected along the northeastern coast of Socotra, and fragments of RSW are found between one and three degrees of latitude north of this island. In the whole Gulf of Aden, the correlation between the deep motions of the floats and the SSH measured by altimetry is strong, at regional scale. The finer scale details of the float trajectories are more often related to the anomalous water masses that they encounter.

    The Persian Gulf Water (PGW is found in the float profiles near Ras ash Sharbatat (near 57° E, 18° N, again with 36.5 in salinity and about 18–19 °C in temperature. These observations were achieved in winter when the southwestward monsoon currents can advect PGW along the South Arabian coast. Fragments of PGW are found in the Arabian Sea between 18 and 20° N and 63 and 65° E, showing that this water mass can escape the Gulf of Oman southeastward, in particular during summer.

  20. Large-Scale Ichthyoplankton and Water Mass Distribution along the South Brazil Shelf

    Science.gov (United States)

    de Macedo-Soares, Luis Carlos Pinto; Garcia, Carlos Alberto Eiras; Freire, Andrea Santarosa; Muelbert, José Henrique

    2014-01-01

    Ichthyoplankton is an essential component of pelagic ecosystems, and environmental factors play an important role in determining its distribution. We have investigated simultaneous latitudinal and cross-shelf gradients in ichthyoplankton abundance to test the hypothesis that the large-scale distribution of fish larvae in the South Brazil Shelf is associated with water mass composition. Vertical plankton tows were collected between 21°27′ and 34°51′S at 107 stations, in austral late spring and early summer seasons. Samples were taken with a conical-cylindrical plankton net from the depth of chlorophyll maxima to the surface in deep stations, or from 10 m from the bottom to the surface in shallow waters. Salinity and temperature were obtained with a CTD/rosette system, which provided seawater for chlorophyll-a and nutrient concentrations. The influence of water mass on larval fish species was studied using Indicator Species Analysis, whereas environmental effects on the distribution of larval fish species were analyzed by Distance-based Redundancy Analysis. Larval fish species were associated with specific water masses: in the north, Sardinella brasiliensis was found in Shelf Water; whereas in the south, Engraulis anchoita inhabited the Plata Plume Water. At the slope, Tropical Water was characterized by the bristlemouth Cyclothone acclinidens. The concurrent analysis showed the importance of both cross-shelf and latitudinal gradients on the large-scale distribution of larval fish species. Our findings reveal that ichthyoplankton composition and large-scale spatial distribution are determined by water mass composition in both latitudinal and cross-shelf gradients. PMID: