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Sample records for binary mixed non-aqueous

  1. Study of complexation process between 4'-nitrobenzo-15-crown-5 and yttrium(III) cation in binary mixed non-aqueous solvents using conductometric method

    Science.gov (United States)

    Habibi, N.; Rounaghi, G. H.; Mohajeri, M.

    2012-12-01

    The complexation reaction of macrocyclic ligand (4'-nitrobenzo-15C5) with Y3+ cation was studied in acetonitrile-methanol (AN-MeOH), acetonitrile-ethanol (AN-EtOH), acetonitrile-dimethylformamide (AN-DMF) and ethylacetate-methanol (EtOAc-MeOH) binary mixtures at different temperatures using conductometry method. The conductivity data show that in all solvent systems, the stoichiometry of the complex formed between 4'-nitrobenzo-15C5 and Y3+ cation is 1: 1 (ML). The stability order of (4'-nitrobenzo-15C5). Y3+ complex in pure non-aqueous solvents at 25°C was found to be: EtOAc > EtOH > AN ≈ DMF > MeOH, and in the case of most compositions of the binary mixed solvents at 25°C it was: AN≈MeOH ≈ AN-EtOH > AN-DMF > EtOAc-MeOH. But the results indicate that the sequence of the stability of the complex in the binary mixed solutions changes with temperature. A non-linear behavior was observed for changes of log K f of (4'-nitrobenzo-15C5 · Y3+) complex versus the composition of the binary mixed solvents, which was explained in terms of solvent-solvent interactions and also the hetero-selective solvation of the species involved in the complexation reaction. The values of thermodynamic parameters (Δ H {c/ℴ} and Δ S {c/ℴ}) for formation of the complex were obtained from temperature dependent of the stability constant using the van't Hoff plots. The results represent that in most cases, the complex is both enthalpy and entropy stabilized and the values and also the sign of thermodynamic parameters are influenced by the nature and composition of the mixed solvents.

  2. Study of complex formation between C18H36N2O6 and UO22+ cation in some binary mixed non-aqueous solutions

    Directory of Open Access Journals (Sweden)

    G.H. Rounaghi

    2017-02-01

    Full Text Available The complexation reaction between UO22+ cation and the macrobicyclic ligand C18H36N2O6 was studied in acetonitrile–dimethylformamide (AN–DMF, acetonitrile–tetrahydrofuran (AN–THF, acetonitrile–dichloromethane (AN–DCM binary solvent solutions at different temperatures using the coductometric method. In most cases, C18H36N2O6 forms a 1:1 [M:L] complex with the UO22+ cation. But in some of the studied solvent systems, in addition to formation of a 1:1 complex, a 1:2 [M:L2] complex is formed in solution. A non-linear behavior was observed for changes of logKf of the (C18H36N2O6·UO22+ complex versus the composition of the binary mixed solvents. The sequence of the stability of the (C18H36N2O6·UO22+ complex in pure solvent systems at 25 °C decreases in the order: AN > THF > DMF. In the case of binary solvent solutions, the stability constant of the complex at 25 °C was found to be: AN–DCM > AN–THF > AN–DMF. The values of thermodynamic quantities (ΔSc°,ΔHc°, for the formation of the complex were obtained from temperature dependence of the stability constant of the complex using the van't Hoff plots. The results show that in all cases, the complex is both entropy and enthalpy stabilized and both of these parameters are affected by the nature and composition of the mixed solvent systems.

  3. Study of complex formation process between 4′-nitrobenzo-18-crown-6 and yttrium(III cation in some binary mixed non-aqueous solvents using the conductometry method

    Directory of Open Access Journals (Sweden)

    Mahboobeh Vafi

    2017-07-01

    Full Text Available The complexation reaction between Y3+ cation and macrocyclic ligand, 4′-nitrobenzo-18-crown-6 (4′NB18C6, was studied in acetonitrile–methanol (AN–MeOH, acetonitrile–1,2-dichloroethane (AN–DCE, acetonitrile–dimethylformamide (AN–DMF and acetonitrile–ethylacetate (AN–EtOAc binary mixed solvent solutions at different temperatures using the conductometric method. The conductance data show that in most cases, the stoichiometry of the complex formed between 4′NB18C6 and Y3+ cation is 1:1 [M:L], but in the case of AN-DCE binary solution (mol% DCE = 50 at 15, 25 and 35 °C, a 2:1 [M2:L] and also a 2:2 [M2:L2] complexes are formed in solution. The results show that the stoichiometry of the complex formed between 4′NB18C6 and Y3+ cation changes with the composition of the mixed solvents and even with temperature. The stability constant of the 1:1 complex was determined using a computer program, GENPLOT. The stability order of (4′NB18C6.Y3+ complex in pure studied solvents at 25 °C was found to be: EtOAc > AN > MeOH > DMF and in the case of the mixed solvent solutions with 25 mol percent of AN at 25 °C was: AN-DCE > AN-EtOAc > AN-MeOH ∼ AN-DMF. The values of stability constant (logKf of (4′NB18C6.Y3+ complex which were obtained from conductometric data, show that the stability of the complex is not only affected by the nature and composition of the solvent system, but it is also influenced by the temperature. In all cases, a non-linear behavior is observed for changes of logKf of the (4′NB18C6.Y3+ complex versus the composition of the binary mixed solvents. The values of standard thermodynamic quantities (ΔH°c and ΔS°c for the complexation process which were obtained from temperature dependence of the stability constant of (4′NB18C6.Y3+ complex, show that depending on the solvent system, in most cases, the complex is enthalpy and also entropy stabilized, but in some cases, it is stabilized or

  4. Structure of binary mixed polymer Langmuir layers

    NARCIS (Netherlands)

    Bernardini, C.

    2012-01-01

    The possibility of preparing 2D stable emulsions through mixing of homopolymers in a Langmuir monolayer is the core topic of this thesis. While colloid science has achieved well established results in the study of bulk dispersed systems, accounts on properties of mixed monomolecular films are

  5. Presence of mixed modes in red giants in binary systems

    Directory of Open Access Journals (Sweden)

    Themeßl Nathalie

    2017-01-01

    Full Text Available The frequencies of oscillation modes in stars contain valueable information about the stellar properties. In red giants the frequency spectrum also contains mixed modes, with both pressure (p and gravity (g as restoring force, which are key to understanding the physical conditions in the stellar core. We observe a high fraction of red giants in binary systems, for which g-dominated mixed modes are not pronounced. This trend leads us to investigate whether this is specific for binary systems or a more general feature. We do so by comparing the fraction of stars with only p-dominated mixed modes in binaries and in a larger set of stars from the APOKASC sample. We find only p-dominated mixed modes in about 50% of red giants in detached eclipsing binaries compared to about 4% in the large sample. This could indicate that this phenomenon is tightly related to binarity and that the binary fraction in the APOKASC sample is about 8%.

  6. Energetics of binary mixed culture of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Bioenergetic analysis of the growth of the binary mixed culture (Pseudomonas aeruginosa and Pseudomonas fluorescence) on phenol chemostat culture was carried out. The data were checked for consistency using carbon and available electron balances. When more than the minimum number of variables are measured, ...

  7. Non-aqueous pigmented inkjet inks

    NARCIS (Netherlands)

    DEROOVER, GEERT; Bernaerts, Katrien; HOOGMARTENS, IVAN

    2009-01-01

    A non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents theA non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to

  8. NON-AQUEOUS PIGMENTED INKJET INKS

    NARCIS (Netherlands)

    DEROOVER, GEERT; Bernaerts, Katrien; HOOGMARTENS, IVAN

    2010-01-01

    A non-aqueous inkjet ink includes a benzimidazolone pigment and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents the residue of polyethyleneimine having a number-average molecular weight of at least 100; A represents

  9. Non-aqueous pigmented inkjet inks

    NARCIS (Netherlands)

    HOOGMARTENS, IVAN; Bernaerts, Katrien; DEROOVER, GEERT

    2008-01-01

    A non-aqueous inkjet ink comprising C.I. Pigment Yellow 150 and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents the residue of polyethyleneimine having a number-average molecular weight of at least 100; A represents

  10. Numerical modeling of two-phase binary fluid mixing using mixed finite elements

    KAUST Repository

    Sun, Shuyu

    2012-07-27

    Diffusion coefficients of dense gases in liquids can be measured by considering two-phase binary nonequilibrium fluid mixing in a closed cell with a fixed volume. This process is based on convection and diffusion in each phase. Numerical simulation of the mixing often requires accurate algorithms. In this paper, we design two efficient numerical methods for simulating the mixing of two-phase binary fluids in one-dimensional, highly permeable media. Mathematical model for isothermal compositional two-phase flow in porous media is established based on Darcy\\'s law, material balance, local thermodynamic equilibrium for the phases, and diffusion across the phases. The time-lag and operator-splitting techniques are used to decompose each convection-diffusion equation into two steps: diffusion step and convection step. The Mixed finite element (MFE) method is used for diffusion equation because it can achieve a high-order and stable approximation of both the scalar variable and the diffusive fluxes across grid-cell interfaces. We employ the characteristic finite element method with moving mesh to track the liquid-gas interface. Based on the above schemes, we propose two methods: single-domain and two-domain methods. The main difference between two methods is that the two-domain method utilizes the assumption of sharp interface between two fluid phases, while the single-domain method allows fractional saturation level. Two-domain method treats the gas domain and the liquid domain separately. Because liquid-gas interface moves with time, the two-domain method needs work with a moving mesh. On the other hand, the single-domain method allows the use of a fixed mesh. We derive the formulas to compute the diffusive flux for MFE in both methods. The single-domain method is extended to multiple dimensions. Numerical results indicate that both methods can accurately describe the evolution of the pressure and liquid level. © 2012 Springer Science+Business Media B.V.

  11. Non-aqueous titration of hydroxamic acids.

    Science.gov (United States)

    Stamey, T W; Christian, R

    1966-01-01

    Benzohydroxamic acid is titrated with 0.1M tetrabutyl-anunonium hydroxide in nine non-aqueous solvents with three different indicating electrodes. The best results are obtained using dimethylformamide as solvent and platinum-platinum electrodes. Four monoprotic and three diprotic hydroxamie acids and iron(III) benzohydroxamate have been successfully titrated with this system. The effect of quantitative additions of carbon dioxide to the titrant on its apparent molarity are found to be dependent on the amount added, the strength and sample size of acid titrated and the solvent used.

  12. Non-aqueous slurries used as thickeners

    Energy Technology Data Exchange (ETDEWEB)

    Hatfield, J C

    1982-04-07

    A non-aqueous slurry is described that is suitable for use as a thickener or viscosifier in oil or gas drilling, fracturing, flow diversion completion or workover fluids. The slurry comprises a water-soluble cellulose ether polymer, a water-insoluble liquid hydrocarbon, a non-ionic surfactant having an HLB of from 7 to 14, and an organo modified clay. There also is described a process for thickening or viscosifying a drilling, fracturing, flow diversion, completion or workover fluid. The use of the slurry prevents bumping during addition to aqueous fluids. (27 claims)

  13. Thermodynamics of Binary Mixed Crystals in the Sub-quasi-chemical/Debye Approximation

    Science.gov (United States)

    van der Kemp, W. J. M.; Verdonk, M. L.

    1995-03-01

    A new statistical model for the description of the thermodynamic properties of binary mixed crystals is discussed. The model is based on an asymmetrical analogue of the quasi-chemical approximation and the Debye model of a solid. With two interchange -energy parameters and two interchange-Debye-temperature parameters, all important thermodynamic functions, at constant volume, of the binary mixed crystal can be calculated as a function of temperature and composition. The binary system {( 1 - x)Nai + xKI}(s) is used for illustration of the model.

  14. PREDICTION OF THE MIXING ENTHALPIES OF BINARY LIQUID ALLOYS BY MOLECULAR INTERACTION VOLUME MODEL

    Institute of Scientific and Technical Information of China (English)

    H.W.Yang; D.P.Tao; Z.H.Zhou

    2008-01-01

    The mixing enthalpies of 23 binary liquid alloys are calculated by molecular interaction volume model (MIVM), which is a two-parameter model with the partial molar infinite dilute mixing enthalpies. The predicted values are in agreement with the experimental data and then indicate that the model is reliable and convenient.

  15. Breaking from binaries - using a sequential mixed methods design.

    Science.gov (United States)

    Larkin, Patricia Mary; Begley, Cecily Marion; Devane, Declan

    2014-03-01

    To outline the traditional worldviews of healthcare research and discuss the benefits and challenges of using mixed methods approaches in contributing to the development of nursing and midwifery knowledge. There has been much debate about the contribution of mixed methods research to nursing and midwifery knowledge in recent years. A sequential exploratory design is used as an exemplar of a mixed methods approach. The study discussed used a combination of focus-group interviews and a quantitative instrument to obtain a fuller understanding of women's experiences of childbirth. In the mixed methods study example, qualitative data were analysed using thematic analysis and quantitative data using regression analysis. Polarised debates about the veracity, philosophical integrity and motivation for conducting mixed methods research have largely abated. A mixed methods approach can contribute to a deeper, more contextual understanding of a variety of subjects and experiences; as a result, it furthers knowledge that can be used in clinical practice. The purpose of the research study should be the main instigator when choosing from an array of mixed methods research designs. Mixed methods research offers a variety of models that can augment investigative capabilities and provide richer data than can a discrete method alone. This paper offers an example of an exploratory, sequential approach to investigating women's childbirth experiences. A clear framework for the conduct and integration of the different phases of the mixed methods research process is provided. This approach can be used by practitioners and policy makers to improve practice.

  16. Mixing process of a binary gas in a density stratified layer

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Tetsuaki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1997-09-01

    This study is to investigate the effect of natural convection on the mixing process by molecular diffusion in a vertical stratified layer of a binary fluid. There are many experimental and analytical studies on natural convection in the vertical fluid layer. However, there are few studies on natural convection with molecular diffusion in the vertical stratified layer of a binary gas. Experimental study has been performed on the combined phenomena of molecular diffusion and natural convection in a binary gas system to investigate the mixing process of the binary gas in a vertical slot consisting of one side heated and the other side cooled. The range of Rayleigh number based on the slot width was about 0 < Ra{sub d} < 7.5 x 10{sup 4}. The density change of the gas mixture and the temperature distribution in the slot was obtained and the mixing process when the heavier gas ingress into the vertical slot filled with the lighter gas from the bottom side of the slot was discussed. The experimental results showed that the mixing process due to molecular diffusion was affected significantly by the natural convection induced by the slightly temperature difference between both vertical walls even if a density difference by the binary gas is larger than that by the temperature difference. (author). 81 refs.

  17. Application of refractive index mixing rules in binary systems of ...

    Indian Academy of Sciences (India)

    Unknown

    expressed in terms of average percentage deviation. The performance ... of these mixing rules is their inability to account for changes in volume and refractivity ..... symmetrical shape and it proposes volume additivity which is the reason for the.

  18. Substrate inhibition kinetics of phenol degradation by binary mixed ...

    African Journals Online (AJOL)

    Steady states of a continuous culture with an inhibitory substrate were used to estimate kinetic parameters under substrate limitation (chemo stat operation). Mixed cultures of an indigenous Pseudomonas fluorescence and Pseudomonas aeruginosa were grown in continuous culture on phenol as the sole source of carbon ...

  19. Application of refractive index mixing rules in binary systems of ...

    Indian Academy of Sciences (India)

    ... entire mole fraction range of hexadecane and heptadecane at the three temperatures. Comparison of various mixing rules has been expressed in terms of average percentage deviation. The performance of the Lorentz- Lorenz and Heller relations is relatively better than that of the Weiner and Gladstone-Dale relations.

  20. Phase behaviour in binary mixed Langmuir-Blodgett monolayers of triglycerides

    NARCIS (Netherlands)

    Zdravkova, A.N.; van der Eerden, J.P.J.M.

    2007-01-01

    Binary mixed monolayers of the triglycerides (TAGs)-tripalmitin (PPP), tristearin (SSS) and triarachidin (AAA) at the air–water interface are investigated with the Langmuir method. Langmuir–Blodgett (LB) layers obtained by deposition on mica are investigated by Atomic Force Microscopy. Combining

  1. The mean ''size'' of polyatomic boxes for a binary mixing

    International Nuclear Information System (INIS)

    Mejdani, R.

    1991-06-01

    In the present work we have studied in detail the problem of the mean ''size'' of mixing of chain-propagating atoms and chain-terminating atoms on a one-dimensional lattice, with respect to the temperature and the interaction constants. Some comparisons of the average chain length of a symmetric system to that of an asymmetric one allows us to state that the asymmetry of bonds play an important role in determining the mean chain length or the mean ''size'' of boxes. (author). 4 refs, 6 figs

  2. Nanostructured Mn-Fe Binary Mixed Oxide: Synthesis, Characterization and Evaluation for Arsenic Removal.

    Science.gov (United States)

    Pillewan, Pradnya; Mukherjee, Shrabanti; Bansiwal, Amit; Rayalu, Sadhana

    2014-07-01

    Adsorption of arsenic on bimetallic Mn and Fe mixed oxide was carried out using both field as well as simulated water. The material was synthesized using hydrothermal method and characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Langmuir and Freundlich adsorption isotherms were computed using batch adsorption studies to determine the adsorption capacity of Mn-Fe binary mixed oxide for arsenic. Adsorption capacity for MFBMO obtained from Freundlich model was found to be 2.048 mg/g for simulated water and 1.084 mg/g for field water. Mn-Fe binary mixed oxide was found to be effective adsorbent for removal of arsenic from water.

  3. Breaking Binaries? Biomedicine and Serostatus Borderlands among Couples with Mixed HIV Status.

    Science.gov (United States)

    Persson, Asha; Newman, Christy E; Ellard, Jeanne

    2017-01-01

    With recent breakthroughs in HIV treatment and prevention, the meanings of HIV-positivity and HIV-negativity are changing at biomedical and community levels. We explore how binary constructions of HIV serostatus identities are giving way to something more complex that brings both welcome possibilities and potential concerns. We draw on research with couples with mixed HIV status to argue that, in the context of lived experiences, serostatus identities have always been more ambiguous than allowed for in HIV discourse. However, their supposed dichotomous quality seems even more dubious now in view of contemporary biomedical technologies. Invoking the anthropological concept of "borderlands," we consider how biomedicine is generating more diverse serostatus identities, widening the options for how to live with HIV, and eroding the stigmatizing serostatus binary that has haunted the epidemic. But we also ask whether this emerging borderland, and its "normalizing" tendencies, is concomitantly giving rise to new and troubling binaries.

  4. Principles of interactions in non-aqueous electrolyte solutions

    NARCIS (Netherlands)

    Lyklema, J.

    2013-01-01

    In this paper a review is presented on the molecular interactions in non-aqueous media of low dielectric permittivity. Qualitative and quantitative distinctions with aqueous solutions are emphasized. The reviewed themes include dispersion forces, dissociation and association equilibria,

  5. Efficient and robust estimation for longitudinal mixed models for binary data

    DEFF Research Database (Denmark)

    Holst, René

    2009-01-01

    This paper proposes a longitudinal mixed model for binary data. The model extends the classical Poisson trick, in which a binomial regression is fitted by switching to a Poisson framework. A recent estimating equations method for generalized linear longitudinal mixed models, called GEEP, is used...... as a vehicle for fitting the conditional Poisson regressions, given a latent process of serial correlated Tweedie variables. The regression parameters are estimated using a quasi-score method, whereas the dispersion and correlation parameters are estimated by use of bias-corrected Pearson-type estimating...... equations, using second moments only. Random effects are predicted by BLUPs. The method provides a computationally efficient and robust approach to the estimation of longitudinal clustered binary data and accommodates linear and non-linear models. A simulation study is used for validation and finally...

  6. Calculating excess volumes of binary solutions with allowance for structural differences between mixed components

    Science.gov (United States)

    Balankina, E. S.

    2016-06-01

    Analytical dependences of a volume's properties on the differences between the geometric structures of initial monosystems are obtained for binary systems simulated by a grain medium. The effect of microstructural parameter k (the ratio of volumes of molecules of mixed components) on the concentration behavior of the relative excess molar volume of different types of real binary solutions is analyzed. It is established that the contribution due to differences between the volumes of molecules and coefficients of the packing density of mixed components is ~80-100% for mutual solutions of n-alkanes and ~55-80% of the experimental value of the relative excess molar volume for water solutions of n-alcohols.

  7. Exact statistical results for binary mixing and reaction in variable density turbulence

    Science.gov (United States)

    Ristorcelli, J. R.

    2017-02-01

    We report a number of rigorous statistical results on binary active scalar mixing in variable density turbulence. The study is motivated by mixing between pure fluids with very different densities and whose density intensity is of order unity. Our primary focus is the derivation of exact mathematical results for mixing in variable density turbulence and we do point out the potential fields of application of the results. A binary one step reaction is invoked to derive a metric to asses the state of mixing. The mean reaction rate in variable density turbulent mixing can be expressed, in closed form, using the first order Favre mean variables and the Reynolds averaged density variance, ⟨ρ2⟩ . We show that the normalized density variance, ⟨ρ2⟩ , reflects the reduction of the reaction due to mixing and is a mix metric. The result is mathematically rigorous. The result is the variable density analog, the normalized mass fraction variance ⟨c2⟩ used in constant density turbulent mixing. As a consequence, we demonstrate that use of the analogous normalized Favre variance of the mass fraction, c″ ⁣2˜ , as a mix metric is not theoretically justified in variable density turbulence. We additionally derive expressions relating various second order moments of the mass fraction, specific volume, and density fields. The central role of the density specific volume covariance ⟨ρ v ⟩ is highlighted; it is a key quantity with considerable dynamical significance linking various second order statistics. For laboratory experiments, we have developed exact relations between the Reynolds scalar variance ⟨c2⟩ its Favre analog c″ ⁣2˜ , and various second moments including ⟨ρ v ⟩ . For moment closure models that evolve ⟨ρ v ⟩ and not ⟨ρ2⟩ , we provide a novel expression for ⟨ρ2⟩ in terms of a rational function of ⟨ρ v ⟩ that avoids recourse to Taylor series methods (which do not converge for large density differences). We have derived

  8. Organic non-aqueous cation-based redox flow batteries

    Science.gov (United States)

    Zhang, Lu; Huang, Jinhua; Burrell, Anthony

    2018-05-08

    The present invention provides a non-aqueous redox flow battery comprising a negative electrode immersed in a non-aqueous liquid negative electrolyte, a positive electrode immersed in a non-aqueous liquid positive electrolyte, and a cation-permeable separator (e.g., a porous membrane, film, sheet, or panel) between the negative electrolyte from the positive electrolyte. During charging and discharging, the electrolytes are circulated over their respective electrodes. The electrolytes each comprise an electrolyte salt (e.g., a lithium or sodium salt), a transition-metal free redox reactant, and optionally an electrochemically stable organic solvent. Each redox reactant is selected from an organic compound comprising a conjugated unsaturated moiety, a boron cluster compound, and a combination thereof. The organic redox reactant of the positive electrolyte comprises a tetrafluorohydroquinone ether compound or a tetrafluorocatechol ether compound.

  9. Organic non-aqueous cation-based redox flow batteries

    Science.gov (United States)

    Jansen, Andrew N.; Vaughey, John T.; Chen, Zonghai; Zhang, Lu; Brushett, Fikile R.

    2016-03-29

    The present invention provides a non-aqueous redox flow battery comprising a negative electrode immersed in a non-aqueous liquid negative electrolyte, a positive electrode immersed in a non-aqueous liquid positive electrolyte, and a cation-permeable separator (e.g., a porous membrane, film, sheet, or panel) between the negative electrolyte from the positive electrolyte. During charging and discharging, the electrolytes are circulated over their respective electrodes. The electrolytes each comprise an electrolyte salt (e.g., a lithium or sodium salt), a transition-metal free redox reactant, and optionally an electrochemically stable organic solvent. Each redox reactant is selected from an organic compound comprising a conjugated unsaturated moiety, a boron cluster compound, and a combination thereof. The organic redox reactant of the positive electrolyte is selected to have a higher redox potential than the redox reactant of the negative electrolyte.

  10. Solubilization of Polycyclic Aromatic Hydrocarbons by Single and Binary Mixed Rhamnolipid-Sophorolipid Biosurfactants.

    Science.gov (United States)

    Song, Dandan; Liang, Shengkang; Yan, Lele; Shang, Yujun; Wang, Xiuli

    2016-07-01

    Biosurfactants are promising additives for surfactant enhanced remediation (SER) technologies due to their low toxicity and high biodegradability. To develop green and efficient additives for SER, the aqueous solubility enhancements of polycyclic aromatic hydrocarbons (PAHs; naphthalene, phenanthrene, and pyrene) by rhamnolipid (RL) and sophorolipid (SL) biosurfactants were investigated in single and binary mixed systems. The solubilization capacities were quantified in terms of the solubility enhancement factor, molar solubilization ratio (MSR), and micelle-water partition coefficient (). Rughbin's model was applied to evaluate the interaction parameters (β) in the mixed RL-SL micelles. The solubility of the PAHs increased linearly with the glycolipid concentration above the critical micelle concentration (CMC) in both single and mixed systems. Binary RL-SL mixtures exhibited greater solubilization than individual glycolipids. At a SL molar fraction of 0.7 to 0.8, the solubilization capacity was the greatest, and the MSR and reached their maximum values, and β values became positive. These results suggest that the two biosurfactants act synergistically to increase the solubility of the PAHs. The solubilization capacity of the RL-SL mixtures increased with increasing temperature and decreased with increasing salinity. The aqueous solubility of phenanthrene reached a maximum value at pH of 5.5. Moreover, the mixed RL-SL systems exhibited a strong ability to solubilize PAHs, even in the presence of heavy metal ions. These mixed biosurfactant systems have the potential to improve the performance of SER technologies using biosurfactants to solubilize hydrophobic organic contaminants by decreasing the applied biosurfactant concentration, which reduces the costs of remediation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  11. An adjoint-based framework for maximizing mixing in binary fluids

    Science.gov (United States)

    Eggl, Maximilian; Schmid, Peter

    2017-11-01

    Mixing in the inertial, but laminar parameter regime is a common application in a wide range of industries. Enhancing the efficiency of mixing processes thus has a fundamental effect on product quality, material homogeneity and, last but not least, production costs. In this project, we address mixing efficiency in the above mentioned regime (Reynolds number Re = 1000 , Peclet number Pe = 1000) by developing and demonstrating an algorithm based on nonlinear adjoint looping that minimizes the variance of a passive scalar field which models our binary Newtonian fluids. The numerical method is based on the FLUSI code (Engels et al. 2016), a Fourier pseudo-spectral code, which we modified and augmented by scalar transport and adjoint equations. Mixing is accomplished by moving stirrers which are numerically modeled using a penalization approach. In our two-dimensional simulations we consider rotating circular and elliptic stirrers and extract optimal mixing strategies from the iterative scheme. The case of optimizing shape and rotational speed of the stirrers will be demonstrated.

  12. Enthalpies of mixing in binary liquid alloys of lutetium with 3d metals

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Michael; Berezutski, Vadim [National Academy of Sciences, Kyiv (Ukraine). I. Frantsevich Institute for Problems of Materials Science; Usenko, Natalia; Kotova, Natalia [Taras Shevchenko National Univ., Kyiv (Ukraine). Dept. of Chemistry

    2017-01-15

    The enthalpies of mixing in binary liquid alloys of lutetium with chromium, cobalt, nickel and copper were determined at 1 773 - 1 947 K by isoperibolic calorimetry. The enthalpies of mixing in the Lu-Cr melts (measured up to 40 at.% Cr) demonstrate endothermic effects (ΔH = 6.88 ± 0.66 kJ . mol{sup -1} at x{sub Lu} = 0.60), whereas significant exothermic enthalpies of mixing have been established within a wide composition region for the Co-Lu, Ni-Lu and Cu-Lu liquid alloys. Minimum values of the integral enthalpy of mixing are as follows: ΔH{sub min} = -23.57 ± 1.41 kJ . mol{sup -1} at x{sub Lu} = 0.38 for the Co-Lu system; ΔH{sub min} = -48.65 ± 2.83 kJ . mol{sup -1} at x{sub Lu} = 0.40 for the Ni-Lu system; ΔH{sub min} = -24.63 ± 1.52 kJ . mol{sup -1} at x{sub Lu} = 0.37 for the Cu-Lu system.

  13. Non-aqueous heavy oil extraction from oil sand

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, George [National Nuclear Security Administration (United States)

    2011-07-01

    The Kansas City plant operated by Honeywell has a long history of working with DOE NNSA on engineering and manufacturing services supporting national security requirements. The plant has developed a non-aqueous method for heavy oil extraction from oil sands. This method is environmentally friendly as it does not use any external body of water, which would normally be contaminated in the conventional method. It is a 2 phase process consisting of terpene, limonene or alpha pinene, and carbon dioxide. The CO2 and terpene phases are both closed loop systems which minimizes material loss. The limonene and alpha pinene are both naturally derived solvents that come from citrus sources or pine trees respectively. Carbon dioxide is an excellent co-solvent with terpene. There is also a possibility for heat loss recovery during the distillation phase. This process produces clean dry sand. Laboratory tests have concluded that this using non-aqueous liquids process works effectively.

  14. Assembly of DNA Architectures in a Non-Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Thomas J. Proctor

    2012-08-01

    Full Text Available In the present work, the procedures for the creation of self-assembled DNA nanostructures in aqueous and non-aqueous media are described. DNA-Surfactant complex formation renders the DNA soluble in organic solvents offering an exciting way to bridge the transition of DNA origami materials electronics applications. The DNA retains its structural features, and these unique geometries provide an interesting candidate for future electronics and nanofabrication applications with potential for new properties. The DNA architectures were first assembled under aqueous conditions, and then characterized in solution (using circular dichroism (CD spectroscopy and on the surface (using atomic force microscopy (AFM. Following aqueous assembly, the DNA nanostructures were transitioned to a non-aqueous environment, where butanol was chosen for optical compatibility and thermal properties. The retention of DNA hierarchical structure and thermal stability in non-aqueous conditions were confirmed via CD spectroscopy. The formation and characterization of these higher order DNA-surfactant complexes is described in this paper.

  15. ELECTROCHEMICAL BEHAVIOUR OF METHYLENE BLUE IN NON-AQUEOUS SOLVENTS

    International Nuclear Information System (INIS)

    Caram, J.A.; Suárez, J.F. Martínez; Gennaro, A.M.; Mirífico, M.V.

    2015-01-01

    Graphical abstract: Display Omitted - Highlights: • The dye is electro-reduced in two separated monoelectronic charge transfers. • Solvent/supporting electrolyte/acid/base modifies the electrochemical parameters. • A dissociation equilibrium of the dye in non-aqueous solvent is proposed. • The electro-generated and stable dye-radical is also chemically produced in EDA or KOH/DMF. • A new species is reversibly formed in KOH/EtOH or ACN. - Abstract: The electrochemical behaviour of methylene blue in solution of non-aqueous solvents with different supporting electrolytes was studied by cyclic voltammetry. Dye electro-reduction presents two well-defined processes of monoelectronic charge transfer yielding a free radical in the first process and an anion in the second electron transfer. Free radical and anion are long living species in some of the studied media. Effects of supporting electrolyte and solvent on the peak potentials, the peak current functions and the reversibility of the charge transfer processes are reported. A dissociation equilibrium of the dye in solution of non-aqueous solvents and the acid or base added determine markedly the electrochemical responses. In the particular cases of KOH/DMF or EDA basic media the chemical formation of the stable methylene blue radical was detected and it was characterized by EPR spectroscopy. A general reaction scheme is proposed

  16. Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Dan Wendt; Greg Mines

    2011-10-01

    Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients Dan Wendt, Greg Mines Idaho National Laboratory The use of mixed working fluids in binary power plants can provide significant increases in plant performance, provided the heat exchangers are designed to take advantage of these fluids non-isothermal phase changes. In the 1980's testing was conducted at DOE's Heat Cycle Research Facility (HCRF) where mixtures of different compositions were vaporized at supercritical pressures and then condensed. This testing had focused on using the data collected to verify that Heat Transfer Research Incorporated (HTRI) codes were suitable for the design of heat exchangers that could be used with mixtures. The HCRF data includes mixture compositions varying from 0% to 40% isopentane and condenser tube orientations of 15{sup o}, 60{sup o}, and 90{sup o} from horizontal. Testing was performed over a range of working fluid and cooling fluid conditions. Though the condenser used in this testing was water cooled, the working fluid condensation occurred on the tube-side of the heat exchanger. This tube-side condensation is analogous to that in an air-cooled condenser. Tube-side condensing heat transfer coefficient information gleaned from the HCRF testing is used in this study to assess the suitability of air-cooled condenser designs for use with mixtures. Results of an air-cooled binary plant process model performed with Aspen Plus indicate that that the optimal mixture composition (producing the maximum net power for the scenario considered) is within the range of compositions for which data exist. The HCRF data is used to assess the impact of composition, tube orientation, and process parameters on the condensing heat transfer coefficients. The sensitivity of the condensing coefficients to these factors is evaluated and the suitability of air-cooled condenser designs with mixtures is assessed. This paper summarizes the evaluation

  17. Non-aqueous removal of sodium from reactor components

    Energy Technology Data Exchange (ETDEWEB)

    Welch, F H; Steele, O P [Rockwell International, Atomics International Division, Canoga Park (United States)

    1978-08-01

    Reactor components from sodium-cooled systems. whether radioactive or not, must have the sodium removed before they can be safely handled for 1) disposal, 2) examination and test, or 3) decontamination, repair, and requalification. In the latter two cases, the sodium must be removed in a manner which will not harm the component. and prevent future use. Two methods for sodium removal using non-aqueous techniques have been studied extensively in the U.S.A. in the past few years: the Alcohol Process, which uses a fully denatured ethanol to react away the sodium; and the Evaporative Process, which uses heat and vacuum to evaporate the sodium from the component.

  18. Non-aqueous removal of sodium from reactor components

    International Nuclear Information System (INIS)

    Welch, F.H.; Steele, O.P.

    1978-01-01

    Reactor components from sodium-cooled systems. whether radioactive or not, must have the sodium removed before they can be safely handled for 1) disposal, 2) examination and test, or 3) decontamination, repair, and requalification. In the latter two cases, the sodium must be removed in a manner which will not harm the component. and prevent future use. Two methods for sodium removal using non-aqueous techniques have been studied extensively in the U.S.A. in the past few years: the Alcohol Process, which uses a fully denatured ethanol to react away the sodium; and the Evaporative Process, which uses heat and vacuum to evaporate the sodium from the component

  19. Non-aqueous electrolytes for lithium ion batteries

    Science.gov (United States)

    Chen, Zonghai; Amine, Khalil

    2015-11-12

    The present invention is generally related to electrolytes containing anion receptor additives to enhance the power capability of lithium-ion batteries. The anion receptor of the present invention is a Lewis acid that can help to dissolve LiF in the passivation films of lithium-ion batteries. Accordingly, one aspect the invention provides electrolytes comprising a lithium salt; a polar aprotic solvent; and an anion receptor additive; and wherein the electrolyte solution is substantially non-aqueous. Further there are provided electrochemical devices employing the electrolyte and methods of making the electrolyte.

  20. Evaluation of a Non-aqueous Ibuprofen-Phospholipid Complex Formulation in Rats.

    Science.gov (United States)

    Li, Chunhua; Xu, Songlin; Liu, Zhidong; Ding, Lingling; Zhao, Xiaobin; Lee, Robert J

    2016-01-01

    In the present study, a non-aqueous ibuprofen-phospholipid complex was developed to reduce the gastrointestinal (GI) toxicity of ibuprofen. A non-aqueous ibuprofen-phospholipid complex (IBU-PC) was prepared by mixing phosal-35SB and ibuprofen. In vitro release behavior was studied using a dissolution apparatus. Irritation to gastrointestinal (GI) tract and pharmacokinetics of IBU-PC were studied in rats. Rapid release of drug occurred with approximately 85% of ibuprofen released from the composition within the first 30 min. The GI injury in IBU-PC-treated rats was minimal compared to those of Advil Liqui-gels-treated group. There was no significant difference between IBU-PC and Motrin-treated groups. The area under the concentration-time curve (AUC0~24) of IBU-PC and Motrin were 366±115 and 391±105 μg/h/ml, respectively. The relative bioavailability of IBU-PC was 94.2%. IBU-PC can decrease GI adverse reaction induced by ibuprofen. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. Application of a radioactive sourced semi portable X-ray spectrometer to the solution of binary mix compositions

    International Nuclear Information System (INIS)

    Butcher, B.M.

    1988-01-01

    In many cases it is far more economically viable to transport individual constituents to a blending plant and produce a series of custom made products than to manufacture at site. This situation exists in many heavy chemical industries or on large building sites. In the cement industry inter-mixed or interground blends containing slag, fly ash, or limestone are produced. These mixes are designed to enhance certain physical properties and to reduce costs. This paper summarises experience of the application of portable isotope source X-ray analysers in achieving quality control of binary mixes

  2. A binary mixed integer coded genetic algorithm for multi-objective optimization of nuclear research reactor fuel reloading

    International Nuclear Information System (INIS)

    Binh, Do Quang; Huy, Ngo Quang; Hai, Nguyen Hoang

    2014-01-01

    This paper presents a new approach based on a binary mixed integer coded genetic algorithm in conjunction with the weighted sum method for multi-objective optimization of fuel loading patterns for nuclear research reactors. The proposed genetic algorithm works with two types of chromosomes: binary and integer chromosomes, and consists of two types of genetic operators: one working on binary chromosomes and the other working on integer chromosomes. The algorithm automatically searches for the most suitable weighting factors of the weighting function and the optimal fuel loading patterns in the search process. Illustrative calculations are implemented for a research reactor type TRIGA MARK II loaded with the Russian VVR-M2 fuels. Results show that the proposed genetic algorithm can successfully search for both the best weighting factors and a set of approximate optimal loading patterns that maximize the effective multiplication factor and minimize the power peaking factor while satisfying operational and safety constraints for the research reactor.

  3. A binary mixed integer coded genetic algorithm for multi-objective optimization of nuclear research reactor fuel reloading

    Energy Technology Data Exchange (ETDEWEB)

    Binh, Do Quang [University of Technical Education Ho Chi Minh City (Viet Nam); Huy, Ngo Quang [University of Industry Ho Chi Minh City (Viet Nam); Hai, Nguyen Hoang [Centre for Research and Development of Radiation Technology, Ho Chi Minh City (Viet Nam)

    2014-12-15

    This paper presents a new approach based on a binary mixed integer coded genetic algorithm in conjunction with the weighted sum method for multi-objective optimization of fuel loading patterns for nuclear research reactors. The proposed genetic algorithm works with two types of chromosomes: binary and integer chromosomes, and consists of two types of genetic operators: one working on binary chromosomes and the other working on integer chromosomes. The algorithm automatically searches for the most suitable weighting factors of the weighting function and the optimal fuel loading patterns in the search process. Illustrative calculations are implemented for a research reactor type TRIGA MARK II loaded with the Russian VVR-M2 fuels. Results show that the proposed genetic algorithm can successfully search for both the best weighting factors and a set of approximate optimal loading patterns that maximize the effective multiplication factor and minimize the power peaking factor while satisfying operational and safety constraints for the research reactor.

  4. The renaissance of non-aqueous uranium chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Liddle, Stephen T. [School of Chemistry, University of Nottingham (United Kingdom)

    2015-07-20

    Prior to the year 2000, non-aqueous uranium chemistry mainly involved metallocene and classical alkyl, amide, or alkoxide compounds as well as established carbene, imido, and oxo derivatives. Since then, there has been a resurgence of the area, and dramatic developments of supporting ligands and multiply bonded ligand types, small-molecule activation, and magnetism have been reported. This review (1) introduces the reader to some of the specialist theories of the area, (2) covers all-important starting materials, (3) surveys contemporary ligand classes installed at uranium, including alkyl, aryl, arene, carbene, amide, imide, nitride, alkoxide, aryloxide, and oxo compounds, (4) describes advances in the area of single-molecule magnetism, and (5) summarizes the coordination and activation of small molecules, including carbon monoxide, carbon dioxide, nitric oxide, dinitrogen, white phosphorus, and alkanes. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Constraining stellar physics from red-giant stars in binaries – stellar rotation, mixing processes and stellar activity

    Directory of Open Access Journals (Sweden)

    Beck P. G.

    2017-01-01

    Full Text Available The unparalleled photometric data obtained by NASA’s Kepler Space Telescope has led to an improved understanding of stellar structure and evolution - in particular for solar-like oscillators in this context. Binary stars are fascinating objects. Because they were formed together, binary systems provide a set of two stars with very well constrained parameters. Those can be used to study properties and physical processes, such as the stellar rotation, dynamics and rotational mixing of elements and allows us to learn from the differences we find between the two components. In this work, we discussed a detailed study of the binary system KIC 9163796, discovered through Kepler photometry. The ground-based follow-up spectroscopy showed that this system is a double-lined spectroscopic binary, with a mass ratio close to unity. However, the fundamental parameters of the components of this system as well as their lithium abundances differ substantially. Kepler photometry of this system allows to perform a detailed seismic analysis as well as to derive the orbital period and the surface rotation rate of the primary component of the system. Indications of the seismic signature of the secondary are found. The differing parameters are best explained with both components located in the early and the late phase of the first dredge up at the bottom of the red-giant branch. Observed lithium abundances in both components are in good agreement with prediction of stellar models including rotational mixing. By combining observations and theory, a comprehensive picture of the system can be drawn.

  6. On The Validity of the Assumed PDF Method for Modeling Binary Mixing/Reaction of Evaporated Vapor in GAS/Liquid-Droplet Turbulent Shear Flow

    Science.gov (United States)

    Miller, R. S.; Bellan, J.

    1997-01-01

    An Investigation of the statistical description of binary mixing and/or reaction between a carrier gas and an evaporated vapor species in two-phase gas-liquid turbulent flows is perfomed through both theroetical analysis and comparisons with results from direct numerical simulations (DNS) of a two-phase mixing layer.

  7. Solubility determination and thermodynamic modelling of allisartan isoproxil in different binary solvent mixtures from T = (278.15 to 313.15) K and mixing properties of solutions

    International Nuclear Information System (INIS)

    Yang, Yaoyao; Yang, Peng; Du, Shichao; Li, Kangli; Zhao, Kaifei; Xu, Shijie; Hou, Baohong; Gong, Junbo

    2016-01-01

    Highlights: • The solubility of allisartan isoproxil in binary solvent mixtures were determined. • Apelblat, CNIBS/R-K and Jouyban-Acree models were used to correlate the solubility. • Solubility parameter theory was used to explain the co-solvency phenomenon. • Regular mixing rules were used to calculate solubility parameter of binary solvents. • The mixing thermodynamics were calculated and discussed based on NRTL model. - Abstract: In this work, the solubility of allisartan isoproxil in binary solvent mixtures, including (acetone + water), (acetonitrile + water) and (methanol + water), was determined by a gravimetric method with the temperature ranging from (278.15 to 313.15) K at atmospheric pressure (p = 0.1 MPa). The solubility of allisartan isoproxil in three binary solvent mixtures all increased with the rising of temperature at a constant solvent composition. For the binary solvent mixtures of (methanol + water), the solubility increased with the increasing of methanol fraction, while it appeared maximum value at a certain solvent composition in the other two binary solvent mixtures (acetone + water and acetonitrile + water). Based on the theory of solubility parameter, Fedors method and two mixing rules were employed to calculate the solubility parameters, by which the proximity of solubility parameters between allisartan isoproxil and binary solvent mixtures explained the co-solvent phenomenon. Additionally, the modified Apelblat equation, CNIBS/R-K model and Jouyban-Acree model were used to correlate the solubility data in binary solvent mixtures, and it turned out that all the three correlation models could give a satisfactory result. Furthermore, the mixing thermodynamic properties were calculated based on NRTL model, which indicated that the mixing process was spontaneous and exothermic.

  8. Non-aqueous nanoporous gold based supercapacitors with high specific energy

    International Nuclear Information System (INIS)

    Hou, Ying; Chen, Luyang; Hirata, Akihiko; Fujita, Takeshi; Chen, Mingwei

    2016-01-01

    In this study, we report that the supercapacitor performance of polypyrrole (PPy) in non-aqueous electrolytes can be dramatically improved by highly conductive nanoporous gold which acts as both the support of active PPy and the current collector of supercapacitors. The excellent electronic conductivity, rich porous structure and large surface area of the nanoporous electrodes give rise to a high specific capacitance and low internal resistance in non-aqueous electrolytes. Combining with a wide working potential window of ~ 2 V, the non-aqueous PPy-based supercapacitors show an extraordinary energy density and power density.

  9. Excess Enthalpies of Mixing of Binary Mixtures of NaCl, KCl, NaBr ...

    African Journals Online (AJOL)

    NJD

    2004-07-01

    Jul 1, 2004 ... NaBr and KBr in Mixed Ternary Solvent Systems at 298.15 K. Bal Raj Deshwala* ... industrial waters and their thermodynamic properties are of practical interest for .... The enthalpy of mixing (∆Hm) is the difference between the excess enthalpy of the ..... tural (categorized by softness, open- ness, and ...

  10. Synergistic Effect of Binary Mixed-Pluronic Systems on Temperature Dependent Self-assembly Process and Drug Solubility

    Directory of Open Access Journals (Sweden)

    Chin-Fen Lee

    2018-01-01

    Full Text Available Mixed Pluronic micelles from very hydrophobic and very hydrophilic copolymers were selected to scrutinize the synergistic effect on the self-assembly process as well as the solubilization capacity of ibuprofen. The tendency of mixing behavior between parent copolymers was systematically examined from two perspectives: different block chain lengths at same hydrophilicity (L92 + F108, +F98, +F88, and +F68, as well as various hydrophobicities at the same PPO moiety (L92 + F88, +F87, and +P84. Temperature-dependent micellization in these binary systems was clearly inspected by the combined use of high sensitivity differential scanning calorimeter (HSDSC and dynamic light scattering (DLS. Changes in heat capacity and size of aggregates at different temperatures during the whole micellization process were simultaneously observed and examined. While distinction of block chain length between parent copolymers increases, the monodispersity of the binary Pluronic systems decreases. However, parent copolymers with distinct PPO moieties do not affirmatively lead to non-cooperative binding, such as the L92 + P84 system. The addition of ibuprofen promotes micellization as well as stabilizes aggregates in the solution. The partial replacement of the hydrophilic Pluronic by a more hydrophobic Pluronic L92 would increase the total hydrophobicity of mixed Pluronics used in the system to substantially enhance the solubility of ibuprofen. The solubility of ibuprofen in the 0.5 wt % L92 + 0.368 wt % P84 system is as high as 4.29 mg/mL, which is 1.4 times more than that of the 0.868 wt % P84 system and 147 times more than that in pure water at 37 °C.

  11. Phase-field modeling of mixing/demixing of regular binary mixtures with a composition-dependent viscosity

    Science.gov (United States)

    Lamorgese, A.; Mauri, R.

    2017-04-01

    We simulate the mixing (demixing) process of a quiescent binary liquid mixture with a composition-dependent viscosity which is instantaneously brought from the two-phase (one-phase) to the one-phase (two-phase) region of its phase diagram. Our theoretical approach follows a standard diffuse-interface model of partially miscible regular binary mixtures wherein convection and diffusion are coupled via a nonequilibrium capillary force, expressing the tendency of the phase-separating system to minimize its free energy. Based on 2D simulation results, we discuss the influence of viscosity ratio on basic statistics of the mixing (segregation) process triggered by a rapid heating (quench), assuming that the ratio of capillary to viscous forces (a.k.a. the fluidity coefficient) is large. We show that, for a phase-separating system, at a fixed value of the fluidity coefficient (with the continuous phase viscosity taken as a reference), the separation depth and the characteristic length of single-phase microdomains decrease monotonically for increasing values of the viscosity of the dispersed phase. This variation, however, is quite small, in agreement with experimental results. On the other hand, as one might expect, at a fixed viscosity of the dispersed phase both of the above statistics increase monotonically as the viscosity of the continuous phase decreases. Finally, we show that for a mixing system the attainment of a single-phase equilibrium state by coalescence and diffusion is retarded by an increase in the viscosity ratio at a fixed fluidity for the dispersed phase. In fact, for large enough values of the viscosity ratio, a thin film of the continuous phase becomes apparent when two drops of the minority phase approach each other, which further retards coalescence.

  12. Dielectric properties of binary solutions a data handbook

    CERN Document Server

    Akhadov, Y Y

    1980-01-01

    Dielectric Properties of Binary Solutions focuses on the investigation of the dielectric properties of solutions, as well as the molecular interactions and mechanisms of molecular processes that occur in liquids. The book first discusses the fundamental formulas describing the dielectric properties of liquids and dielectric data for binary systems of non-aqueous solutions. Topics include permittivity and dielectric dispersion parameters of non-aqueous solutions of organic and inorganic compounds. The text also tackles dielectric data for binary systems of aqueous solutions, including permittiv

  13. Efficacy of bi-component cocrystals and simple binary eutectics screening using heat of mixing estimated under super cooled conditions.

    Science.gov (United States)

    Cysewski, Piotr

    2016-07-01

    The values of excess heat characterizing sets of 493 simple binary eutectic mixtures and 965 cocrystals were estimated under super cooled liquid condition. The application of a confusion matrix as a predictive analytical tool was applied for distinguishing between the two subsets. Among seven considered levels of computations the BP-TZVPD-FINE approach was found to be the most precise in terms of the lowest percentage of misclassified positive cases. Also much less computationally demanding AM1 and PM7 semiempirical quantum chemistry methods are likewise worth considering for estimation of the heat of mixing values. Despite intrinsic limitations of the approach of modeling miscibility in the solid state, based on components affinities in liquids under super cooled conditions, it is possible to define adequate criterions for classification of coformers pairs as simple binary eutectics or cocrystals. The predicted precision has been found as 12.8% what is quite accepted, bearing in mind simplicity of the approach. However, tuning theoretical screening to such precision implies the exclusion of many positive cases and this wastage exceeds 31% of cocrystals classified as false negatives. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. A note on the entropy of mixing of liquid sodium-caesium and other binary alkali alloys

    International Nuclear Information System (INIS)

    Alonso, J.A.; Gallego, L.J.

    1985-01-01

    The entropy of formation of Na-Cs liquid alloys. ΔS, is nearly ideal. This is surprising considering that the ratio between the pure metal volumes is about 3.0. In this Letter it is shown by means of a density functional calculation that the ratio between the effective volumes in the liquid alloy changes to nearly 1.5. This ratio, used in conjunction with Flory's formula for the entropy of mixing, allows quite accurate reproduction of the ideal behaviour of ΔS. It is also shown that this feature of the ratios of atomic volumes is not exclusive to Na-Cs but is common to all the family of binary liquid alkali alloys. (author)

  15. Recoil implantation reactions in binary mixtures of catcher complexes and in mixed ligand catchers

    International Nuclear Information System (INIS)

    Sekine, Tsutomu; Sano, Masaaki; Yoshihara, Kenji

    1989-01-01

    Recoil implantation reactions were studied in binary mixtures of catcher complexes of tris(β-diketonato)metal(III) and in single-component catcher complexes of Cr(acac) n (dbm) 3-n where n=1 and 2. For the mixtures of M(acac) 3 and M(dbm) 3 , the products of 51 Cr(acac) 3 and 51 Cr(dbm) 3 were obtained as major components while 51 Cr(acac) 2 (dbm) and 51 Cr(acac)(dbm) 2 were seen as minor components. For the single component catcher complexes, predominant chemical species were parent retention type compounds. In addition to retentions there were product distributions which indicated a strong preference for acac pickup. The results were interpreted by a model which involves displacement reaction as a main process and ligand pickup reactions as side processes. (orig.)

  16. The transition model test for serial dependence in mixed-effects models for binary data

    DEFF Research Database (Denmark)

    Breinegaard, Nina; Rabe-Hesketh, Sophia; Skrondal, Anders

    2017-01-01

    Generalized linear mixed models for longitudinal data assume that responses at different occasions are conditionally independent, given the random effects and covariates. Although this assumption is pivotal for consistent estimation, violation due to serial dependence is hard to assess by model...

  17. Enzyme Stability and Activity in Non-Aqueous Reaction Systems: A Mini Review

    Directory of Open Access Journals (Sweden)

    Shihui Wang

    2016-02-01

    Full Text Available Enormous interest in biocatalysis in non-aqueous phase has recently been triggered due to the merits of good enantioselectivity, reverse thermodynamic equilibrium, and no water-dependent side reactions. It has been demonstrated that enzyme has high activity and stability in non-aqueous media, and the variation of enzyme activity is attributed to its conformational modifications. This review comprehensively addresses the stability and activity of the intact enzymes in various non-aqueous systems, such as organic solvents, ionic liquids, sub-/super-critical fluids and their combined mixtures. It has been revealed that critical factors such as Log P, functional groups and the molecular structures of the solvents define the microenvironment surrounding the enzyme molecule and affect enzyme tertiary and secondary structure, influencing enzyme catalytic properties. Therefore, it is of high importance for biocatalysis in non-aqueous media to elucidate the links between the microenvironment surrounding enzyme surface and its stability and activity. In fact, a better understanding of the correlation between different non-aqueous environments and enzyme structure, stability and activity can contribute to identifying the most suitable reaction medium for a given biotransformation.

  18. Asteroseismology of Red-Giant Stars: Mixed Modes, Differential Rotation, and Eccentric Binaries

    Science.gov (United States)

    Beck, Paul G.

    2013-12-01

    Astronomers are aware of rotation in stars since Galileo Galilei attributed the movement of sunspots to rotation of the Sun in 1613. In contrast to the Sun, whose surface can be resolved by small telescopes or even the (protected) eye, we detect stars as point sources with no spatial information. Numerous techniques have been developed to derive information about stellar rotation. Unfortunately, most observational data allow only for the surface rotational rate to be inferred. The internal rotational profile, which has a great effect on the stellar structure and evolution, remains hidden below the top layers of the star - the essential is hidden to the eyes. Asteroseismology allows us to "sense" indirectly deep below the stellar surface. Oscillations that propagate through the star provide information about the deep stellar interiors while they also distort the stellar surface in characteristic patterns leading to detectable brightness or velocity variations. Also, certain oscillation modes are sensitive to internal rotation and carry information on how the star is spinning deep inside. Thanks to the unprecedented quality of NASA's space telescope Kepler, numerous detailed observations of stars in various evolutionary stages are available. Such high quality data allow that for many stars, rotation can not only be constrained from surface rotation, but also investigated through seismic studies. The work presented in this thesis focuses on the oscillations and internal rotational gradient of evolved single and binary stars. It is shown that the seismic analysis can reach the cores of oscillating red-giant stars and that these cores are rapidly rotating, while nested in a slowly rotating convective envelope.

  19. Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + ethyl pentanoate + ethyl ethanoate

    International Nuclear Information System (INIS)

    Pérez, Noelia; Fernández, Luís; Ortega, Juan; Toledo, Francisco J.; Wisniak, Jaime

    2012-01-01

    Highlights: ► Excess enthalpies and volumes were measured for ester–ester–alkane. ► Mixing behaviour for ester–ester, ester–alkane and ester–ester–alkane are analyzed. ► Correlations with a new polynomial model reproduce well the mixing properties. ► UNIFAC predictions for h E result acceptable excluding the ester–ester mixtures. - Abstract: Excess thermodynamic properties V m E and H m E , have been measured for the ternary mixture dodecane + ethyl pentanoate + ethyl ethanoate and for the corresponding binaries dodecane + ethyl pentanoate, dodecane + ethyl ethanoate, ethyl pentanoate + ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H m E yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.

  20. Rheology and microstructure of binary mixed gel of rice bran protein-whey: effect of heating rate and whey addition.

    Science.gov (United States)

    Rafe, Ali; Vahedi, Elnaz; Hasan-Sarei, Azadeh Ghorbani

    2016-08-01

    Rice bran protein (RBP) is a valuable plant protein which has unique nutritional and hypoallergenic properties. Whey proteins have wide applications in the food industry, such as in dairy, meat and bakery products. Whey protein concentrate (WPC), RBP and their mixtures at different ratios (1:1, 1:2, 1:5 and 1:10 w/w) were heated from 20 to 90 °C at different heating rates (0.5, 1, 5 and 10 °C min(-1) ). The storage modulus (G') and gelling point (Tgel ) of WPC were higher than those of RBP, indicating the good ability of WPC to develop stiffer networks. By increasing the proportion of WPC in mixed systems, G' was increased and Tgel was reduced. Nevertheless, the elasticity of all binary mixtures was lower than that of WPC alone. Tgel and the final G' of RBP-WPC blends were increased by raising the heating rate. The RBP-WPC mixtures developed more elastic gels than RBP alone at different heating rates. RBP had a fibrillar and lentil-like structure whose fibril assembly had smaller structures than those of WPC. The gelling structure of the mixed gel of WPC-RBP was improved by adding WPC. Indeed, by adding WPC, gels tended to show syneresis and had lower water-holding capacity. Furthermore, the gel structure was produced by adding WPC to the non-gelling RBP, which is compatible with whey and can be applied as a functional food for infants and/or adults. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  1. Generalized linear mixed model for binary outcomes when covariates are subject to measurement errors and detection limits.

    Science.gov (United States)

    Xie, Xianhong; Xue, Xiaonan; Strickler, Howard D

    2018-01-15

    Longitudinal measurement of biomarkers is important in determining risk factors for binary endpoints such as infection or disease. However, biomarkers are subject to measurement error, and some are also subject to left-censoring due to a lower limit of detection. Statistical methods to address these issues are few. We herein propose a generalized linear mixed model and estimate the model parameters using the Monte Carlo Newton-Raphson (MCNR) method. Inferences regarding the parameters are made by applying Louis's method and the delta method. Simulation studies were conducted to compare the proposed MCNR method with existing methods including the maximum likelihood (ML) method and the ad hoc approach of replacing the left-censored values with half of the detection limit (HDL). The results showed that the performance of the MCNR method is superior to ML and HDL with respect to the empirical standard error, as well as the coverage probability for the 95% confidence interval. The HDL method uses an incorrect imputation method, and the computation is constrained by the number of quadrature points; while the ML method also suffers from the constrain for the number of quadrature points, the MCNR method does not have this limitation and approximates the likelihood function better than the other methods. The improvement of the MCNR method is further illustrated with real-world data from a longitudinal study of local cervicovaginal HIV viral load and its effects on oncogenic HPV detection in HIV-positive women. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Thermometric titration of some monoprotic and diprotic acids in aqueous and non-aqueous media.

    Science.gov (United States)

    Harries, R J

    1968-12-01

    Some mono- and diprotic acids have been titrated thermometrically with strong alkalis in aqueous and non-aqueous media. Thermograms with sharp arrest points were obtained, from which heats of neutralization were measured. Heats of neutralization in the media used were compared and an effect attributable to hydrogen bonding was found.

  3. Carbon dioxide assist for non-aqueous sodium–oxygen batteries

    KAUST Repository

    Das, Shyamal K.; Xu, Shaomao; Archer, Lynden A.

    2013-01-01

    We report a novel non-aqueous Na-air battery that utilizes a gas mixture of CO2 and O2. The battery exhibits a high specific energy of 6500-7000 Whkg- 1 (based on the carbon mass) over a range of CO2 feed compositions. The energy density achieved

  4. Enzymes from solvent-tolerant microbes: useful biocatalysts for non-aqueous enzymology.

    Science.gov (United States)

    Gupta, Anshu; Khare, S K

    2009-01-01

    Solvent-tolerant microbes are a newly emerging class that possesses the unique ability to thrive in the presence of organic solvents. Their enzymes adapted to mediate cellular and metabolic processes in a solvent-rich environment and are logically stable in the presence of organic solvents. Enzyme catalysis in non-aqueous/low-water media is finding increasing applications for the synthesis of industrially important products, namely peptides, esters, and other trans-esterification products. Solvent stability, however, remains a prerequisite for employing enzymes in non-aqueous systems. Enzymes, in general, get inactivated or give very low rates of reaction in non-aqueous media. Thus, early efforts, and even some recent ones, have aimed at stabilization of enzymes in organic media by immobilization, surface modifications, mutagenesis, and protein engineering. Enzymes from solvent-tolerant microbes appear to be the choicest source for studying solvent-stable enzymes because of their unique ability to survive in the presence of a range of organic solvents. These bacteria circumvent the solvent's toxic effects by virtue of various adaptations, e.g. at the level of the cytoplasmic membrane, by degradation and transformation of solvents, and by active excretion of solvents. The recent screening of these exotic microbes has generated some naturally solvent-stable proteases, lipases, cholesterol oxidase, cholesterol esterase, cyclodextrin glucanotransferase, and other important enzymes. The unique properties of these novel biocatalysts have great potential for applications in non-aqueous enzymology for a range of industrial processes.

  5. Sedimentation behaviour and colloidal properties of porous, chemically modified silicas in non-aqueous solvents

    NARCIS (Netherlands)

    Vissers, J.P.C.; Laven, J.; Claessens, H.A.; Cramers, C.A.M.G.; Agterof, W.G.M.

    1997-01-01

    The sedimentation behaviour and colloidal properties of porous, chemically modified silicas dispersed in non-aqueous solvents have been studied. The free settling behaviour of non-aggregated silica suspensions could effectively be described with a modified Stokes equation that takes into account the

  6. Non-aqueous metathesis as a general approach to prepare nanodispersed materials: Case study of scheelites

    International Nuclear Information System (INIS)

    Afanasiev, Pavel

    2015-01-01

    A general approach to the preparation of inorganic nanoparticles is proposed, using metathesis of precursor salts in non-aqueous liquids. Nanoparticles of scheelites AMO 4 (A=Ba, Sr, Ca; M=Mo, W), were obtained with a quantitative yield. Precipitations in formamide, N-methylformamide, propylene carbonate, DMSO and polyols often provide narrow particle size distributions. Advantageous morphology was explained by strong ionic association in non-aqueous solvents, leading to slow nucleation and negligible Ostwald ripening. Mean particle size below 10 nm and high specific surface areas were obtained for several Ca(Sr)Mo(W)O 4 materials, making them promising for applications as adsorbents or catalysts. Zeta-potential of scheelites in aqueous suspensions showed negative values in a wide range of pH. Systematic study of optical properties demonstrated variation of optical gap in the sequences W>Mo and Ba>Sr>Ca. The observed trends were reproduced by DFT calculations. No quantum confinement effect was observed for small particles, though the surface states induce low-energy features in the optical spectra. - Graphical abstract: Scheelites AMO 4 (A=Ca, Sr, Ba; M=Mo, W) were prepared in various non-aqueous liquids with high specific surface areas and narrow size distributions. The optical gap of scheelites changes in the series Canon-aqueous liquids. • Narrow size distributions explained by ionic association in non-aqueous media. • Nanoparticles of less than 10 nm size and highest ever specific surface areas were obtained. • Optical gap of scheelites changes in the series Ca

  7. Equation of state modeling of the phase equilibria of asymmetric CO2+n-alkane binary systems using mixing rules cubic with respect to mole fraction

    DEFF Research Database (Denmark)

    Cismondi, Martin; Mollerup, Jørgen M.; Zabaloy, Marcelo S.

    2010-01-01

    for a great diversity of mixtures. Nevertheless, the models for representing phase equilibria and physico-chemical properties of asymmetric systems may require more flexible mixing rules than the classical quadratic van der Waals (vdW) mixing rules or their equivalent (with regard to the number of available...... interaction parameters) in modern equations of state.In particular, the phase equilibria of binary mixtures containing CO2 and heavy n-alkanes have been studied by an important number of authors and using different types of models, achieving only partially accurate results and realizing the difficulties...

  8. Thermodynamic Study of the Complexation of p-Isopropylcalix[6]arene with Cs+ Cation in Dimethylsulfoxide-Acetonitrile Binary Media

    Directory of Open Access Journals (Sweden)

    Gholam Hossein Rounaghi

    2011-09-01

    Full Text Available The complexation reactions between the macrocyclic ionophore, p-isopropylcalix[6]arene and Cs+ cation were studied in dimethylsulfoxide–acetonitrile (DMSO-AN binary non-aqueous solvents at different temperatures using a conductometry method. The conductance data show that the stoichiometry of the (p-isopropylcalix[6]-arene·Cs+ complex in all binary mixed solvents is 1:1. The stability of the complexes is affected by the composition of the binary solvent media and a non-linear behavior was observed for changes of log Kf of the complex versus the composition of the binary mixed solvents. The thermodynamic parameters (DH°c and DS°c for formation of (p-isopropyl-calix[6]arene·Cs+ complex were obtained from temperature dependence of the stability constant and the obtained results show that the (p-isopropylcalix[6]arene·Cs+ complex is enthalpy destabilized, but entropy stabilized, and the values of the mentioned parameters are affected strongly by the nature and composition of the binary mixed solvents.

  9. DFT Study On Effects of CO2 Contamination in Non-Aqueous Li-Air Batteries

    DEFF Research Database (Denmark)

    Mekonnen, Yedilfana Setarge; Mýrdal, Jón Steinar Garðarsson; Vegge, Tejs

    2013-01-01

    Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials are investig...... and result in an increased battery capacity. However, CO2 contamination on the Li2O2 surface confirms an asymmetric increase in the overpotentials; particularly the charging overvoltage exhibits sustantial increase, which would reduce the efficiency of the Li-air battery.......Density Functional Theory (DFT) studies on the effects of carbon dioxide (CO2) contamination at the cathode of rechargeable non-aqueous Li-O2 batteries, where the insulating material Lithium peroxide (Li2O2) is the main discharge product. The Li2O2 growth mechanism and overpotentials...

  10. NABTIT-a computer program for non-aqueous acid-base titration.

    Science.gov (United States)

    Budevsky, O; Zikolova, T; Tencheva, J

    1988-11-01

    A program NABTIT written in BASIC has been developed for the treatment of data (ml/mV) obtained from potentiometric acid-base titrations in non-aqueous solvents. No preliminary information on equilibrium constants is required for the input. The treatment of the data is based on known equations and uses least-squares procedures. The essence of the method is to determine the equivalence volume (V(e)) accurately, and to use the data acquired by adding titrant after V(e) for the pH*-calibration of the non-aqueous potentiometric cell. As a by-product or the calculations, the pK* value of the substance titrated is also obtained, and in some cases the autoprotolysis constant of the medium (pK*(s)). Good agreement between experiment and theory was found in the treatment of data obtained for water and methanol-water mixtures.

  11. Influence of clay and surfactant content in non-aqueous fluid rheology

    International Nuclear Information System (INIS)

    Guedes, I.C.; Gomes, N.L.; Menezes, R.R.; Campos, L.F.A.; Ferreira, H.S.

    2012-01-01

    The bentonite clay used as viscosity agent in the production of non-aqueous fluids cannot be used without organic treatment for their surfaces to become hydrophobic. These clays are called organophilic clays, and are generally obtained by adding, in an aqueous way, ionic or a nonionic surfactant. Recent studies of the variables involved in the dispersion of bentonite clays and in the process of organophilization, showed their lack of influence. This work aims to study the influence of clay content and surfactants on the rheology of nonaqueous fluids. To this end, the clays were treats and characterized, evidencing the incorporation of the surfactant, and then formulated non-aqueous fluids, following PETROBRAS standards, being possible to verify the influence of clay content and surfactant both from the point of view as the characterizing and rheological behavior. (author)

  12. A critical overview of non-aqueous capillary electrophoresis. Part II: separation efficiency and analysis time.

    Science.gov (United States)

    Kenndler, Ernst

    2014-03-28

    A survey of the literature on non-aqueous capillary zone electrophoresis leaves one with the impression of a prevailing notion that non-aqueous conditions are principally more favorable than conventional aqueous media. Specifically, the application of organic solvents in capillary zone electrophoresis (CZE) is believed to provide the general advantages of superior separation efficiency, higher applicable electric field strength, and shorter analysis time. These advantages, however, are often claimed without providing any experimental evidence, or based on rather uncritical comparisons of limited sets of arbitrarily selected separation results. Therefore, the performance characteristics of non-aqueous vs. aqueous CZE certainly deserve closer scrutiny. The primary intention of Part II of this review is to give a critical survey of the literature on non-aqueous capillary electrophoresis (NACE) that has emerged over the last five years. Emphasis is mainly placed on those studies that are concerned with the aspects of plate height, plate number, and the crucial mechanisms contributing to zone broadening, both in organic and aqueous conditions. To facilitate a deeper understanding, this treatment covers also the theoretical fundamentals of peak dispersion phenomena arising from wall adsorption; concentration overload (electromigration dispersion); longitudinal diffusion; and thermal gradients. Theoretically achievable plate numbers are discussed, both under limiting (at zero ionic strength) and application-relevant conditions (at finite ionic strength). In addition, the impact of the superimposed electroosmotic flow contributions to overall CZE performance is addressed, both for aqueous and non-aqueous media. It was concluded that for peak dispersion due to wall adsorption and due to concentration overload (electromigration dispersion, leading to peak triangulation) no general conjunction with the solvent can be deduced. This is in contrast to longitudinal diffusion: the

  13. Studies on ultrasonic velocity and electrical conductivity of samarium soaps in non-aqueous medium

    International Nuclear Information System (INIS)

    Mehrotra, K.N.; Chauhan, M.; Shukla, R.K.

    1990-01-01

    The ultrasonic velocity of solutions of samarium soaps in non-aqueous medium has been measured at a constant temperature and the results have been used to evaluate the various acoustic parameters. The pre-micellar association and the formation of micelles in samarium soap solutions have been determined by conductometric measurements. The molar conductance at infinite dilution, degree of ionisation and ionisation constant have been evaluated. The results show that samarium soaps behave as weak electrolyte in dilute solutions. (Authors)

  14. Prevalence of pure versus mixed snow cover pixels across spatial resolutions in alpine environments: implications for binary and fractional remote sensing approaches

    Science.gov (United States)

    Selkowitz, David J.; Forster, Richard; Caldwell, Megan K.

    2014-01-01

    Remote sensing of snow-covered area (SCA) can be binary (indicating the presence/absence of snow cover at each pixel) or fractional (indicating the fraction of each pixel covered by snow). Fractional SCA mapping provides more information than binary SCA, but is more difficult to implement and may not be feasible with all types of remote sensing data. The utility of fractional SCA mapping relative to binary SCA mapping varies with the intended application as well as by spatial resolution, temporal resolution and period of interest, and climate. We quantified the frequency of occurrence of partially snow-covered (mixed) pixels at spatial resolutions between 1 m and 500 m over five dates at two study areas in the western U.S., using 0.5 m binary SCA maps derived from high spatial resolution imagery aggregated to fractional SCA at coarser spatial resolutions. In addition, we used in situ monitoring to estimate the frequency of partially snow-covered conditions for the period September 2013–August 2014 at 10 60-m grid cell footprints at two study areas with continental snow climates. Results from the image analysis indicate that at 40 m, slightly above the nominal spatial resolution of Landsat, mixed pixels accounted for 25%–93% of total pixels, while at 500 m, the nominal spatial resolution of MODIS bands used for snow cover mapping, mixed pixels accounted for 67%–100% of total pixels. Mixed pixels occurred more commonly at the continental snow climate site than at the maritime snow climate site. The in situ data indicate that some snow cover was present between 186 and 303 days, and partial snow cover conditions occurred on 10%–98% of days with snow cover. Four sites remained partially snow-free throughout most of the winter and spring, while six sites were entirely snow covered throughout most or all of the winter and spring. Within 60 m grid cells, the late spring/summer transition from snow-covered to snow-free conditions lasted 17–56 days and averaged 37

  15. Performance and cost characteristics of multi-electron transfer, common ion exchange non-aqueous redox flow batteries

    Science.gov (United States)

    Laramie, Sydney M.; Milshtein, Jarrod D.; Breault, Tanya M.; Brushett, Fikile R.; Thompson, Levi T.

    2016-09-01

    Non-aqueous redox flow batteries (NAqRFBs) have recently received considerable attention as promising high energy density, low cost grid-level energy storage technologies. Despite these attractive features, NAqRFBs are still at an early stage of development and innovative design techniques are necessary to improve performance and decrease costs. In this work, we investigate multi-electron transfer, common ion exchange NAqRFBs. Common ion systems decrease the supporting electrolyte requirement, which subsequently improves active material solubility and decreases electrolyte cost. Voltammetric and electrolytic techniques are used to study the electrochemical performance and chemical compatibility of model redox active materials, iron (II) tris(2,2‧-bipyridine) tetrafluoroborate (Fe(bpy)3(BF4)2) and ferrocenylmethyl dimethyl ethyl ammonium tetrafluoroborate (Fc1N112-BF4). These results help disentangle complex cycling behavior observed in flow cell experiments. Further, a simple techno-economic model demonstrates the cost benefits of employing common ion exchange NAqRFBs, afforded by decreasing the salt and solvent contributions to total chemical cost. This study highlights two new concepts, common ion exchange and multi-electron transfer, for NAqRFBs through a demonstration flow cell employing model active species. In addition, the compatibility analysis developed for asymmetric chemistries can apply to other promising species, including organics, metal coordination complexes (MCCs) and mixed MCC/organic systems, enabling the design of low cost NAqRFBs.

  16. Improving the treatment of non-aqueous phase TCE in low permeability zones with permanganate.

    Science.gov (United States)

    Chokejaroenrat, Chanat; Comfort, Steve; Sakulthaew, Chainarong; Dvorak, Bruce

    2014-03-15

    Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is a particularly challenging issue for injection-based remedial treatments. Our objective was to improve the sweeping efficiency of permanganate (MnO4(-)) into LPZs to treat high concentrations of TCE. This was accomplished by conducting transport experiments that quantified the penetration of various permanganate flooding solutions into a LPZ that was spiked with non-aqueous phase (14)C-TCE. The treatments we evaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilization aids that minimized MnO2 rind formation and (iii) a phase-transfer catalyst. In addition, we quantified the ability of these flooding solutions to improve TCE destruction under batch conditions by developing miniature LPZ cylinders that were spiked with (14)C-TCE. Transport experiments showed that MnO4(-) alone was inefficient in penetrating the LPZ and reacting with non-aqueous phase TCE, due to a distinct and large MnO2 rind that inhibited the TCE from further oxidant contact. By including xanthan with MnO4(-), the sweeping efficiency increased (90%) but rind formation was still evident. By including the stabilization aid, sodium hexametaphosphate (SHMP) with xanthan, permanganate penetrated 100% of the LPZ, no rind was observed, and the percentage of TCE oxidized increased. Batch experiments using LPZ cylinders allowed longer contact times between the flooding solutions and the DNAPL and results showed that SHMP+MnO4(-) improved TCE destruction by ∼16% over MnO4(-) alone (56.5% vs. 40.1%). These results support combining permanganate with SHMP or SHMP and xanthan as a means of treating high concentrations of TCE in low permeable zones. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Prediction of the theoretical capacity of non-aqueous lithium-air batteries

    International Nuclear Information System (INIS)

    Tan, Peng; Wei, Zhaohuan; Shyy, W.; Zhao, T.S.

    2013-01-01

    Highlights: • The theoretical capacity of non-aqueous lithium-air batteries is predicted. • Key battery design parameters are defined and considered. • The theoretical battery capacity is about 10% of the lithium capacity. • The battery mass and volume changes after discharge are also studied. - Abstract: In attempt to realistically assess the high-capacity feature of emerging lithium-air batteries, a model is developed for predicting the theoretical capacity of non-aqueous lithium-air batteries. Unlike previous models that were formulated by assuming that the active materials and electrolyte are perfectly balanced according to the electrochemical reaction, the present model takes account of the fraction of the reaction products (Li 2 O 2 and Li 2 O), the utilization of the onboard lithium metal, the utilization of the void volume of the porous cathode, and the onboard excess electrolyte. Results show that the gravimetric capacity increases from 1033 to 1334 mA h/g when the reaction product varies from pure Li 2 O 2 to pure Li 2 O. It is further demonstrated that the capacity declines drastically from 1080 to 307 mA h/g when the case of full utilization of the onboard lithium is altered to that only 10% of the metal is utilized. Similarly, the capacity declines from 1080 to 144 mA h/g when the case of full occupation of the cathode void volume by the reaction products is varied to that only 10% of the void volume is occupied. In general, the theoretical gravimetric capacity of typical non-aqueous lithium-air batteries falls in the range of 380–450 mA h/g, which is about 10–12% of the gravimetric capacity calculated based on the energy density of the lithium metal. The present model also facilitates the study of the effects of different parameters on the mass and volume change of non-aqueous lithium-air batteries

  18. High voltage rechargeable magnesium batteries having a non-aqueous electrolyte

    Science.gov (United States)

    Doe, Robert Ellis; Lane, George Hamilton; Jilek, Robert E.; Hwang, Jaehee

    2016-03-22

    A rechargable magnesium battery having an non-aqueous electrolyte is provided. The properties of the electrolyte include high conductivity, high Coulombic efficiency, and an electrochemical window that can exceed 3.5 V vs. Mg/Mg.sup.+2. The use of the electrolyte promotes the electrochemical deposition and dissolution of Mg without the use of any Grignard reagents, other organometallic materials, tetraphenyl borate, or tetrachloroaluminate derived anions. Other Mg-containing electrolyte systems that are expected to be suitable for use in secondary batteries are also described.

  19. Electrochemical deposition of coatings of highly entropic alloys from non-aqueous solutions

    Directory of Open Access Journals (Sweden)

    Jeníček V.

    2016-03-01

    Full Text Available The paper deals with electrochemical deposition of coatings of highly entropic alloys. These relatively new materials have been recently intensively studied. The paper describes the first results of electrochemical coating with highly entropic alloys by deposition from non-aqueous solutions. An electrochemical device was designed and coatings were deposited. The coatings were characterised with electronic microscopy scanning, atomic absorption spectrometry and X-ray diffraction methods and the combination of methods of thermic analysis of differential scanning calorimetry and thermogravimetry.

  20. A thermodynamic study of complexation process between N, N'-dipyridoxylidene(1,4-butanediamine) and Cd2+ in some binary mixed solvents using conductometry

    Science.gov (United States)

    Ebrahimpoor, Sonia; Khoshnood, Razieh Sanavi; Beyramabadi, S. Ali

    2016-12-01

    Complexation of the Cd2+ ion with N, N'-dipyridoxylidene(1,4-butanediamine) Schiff base was studied in pure solvents including acetonitrile (AN), ethanol (EtOH), methanol (MeOH), tetrahydrofuran (THF), dimethylformamide (DMF), water (H2O), and various binary solvent mixtures of acetonitrile-ethanol (AN-EtOH), acetonitrile-methanol (AN-MeOH), acetonitrile-tetrahydrofuran (AN-THF), acetonitrile-dimethylformamide (AN-DMF), and acetonitrile-water (AN-H2O) systems at different temperatures using the conductometric method. The conductance data show that the stoichiometry of complex is 1: 1 [ML] in all solvent systems. A non-linear behavior was observed for changes of log K f of [Cd( N, N'-dipyridoxylidene(1,4-butanediamine)] complex versus the composition of the binary mixed solvents, which was explained in terms of solvent-solvent interactions. The results show that the thermodynamics of complexation reaction is affected by the nature and composition of the mixed solvents.

  1. Non-aqueous energy storage devices using graphene nanosheets synthesized by green route

    Directory of Open Access Journals (Sweden)

    Dattakumar Mhamane

    2013-04-01

    Full Text Available In this paper we report the use of triethylene glycol reduced graphene oxide (TRGO as an electrode material for non-aqueous energy storage devices such as supercapacitors and Li-ion batteries. TRGO based non–aqueous symmetric supercapacitor is constructed and shown to deliver maximum energy and power densities of 60.4 Wh kg–1 and 0.15 kW kg–1, respectively. More importantly, symmetric supercapacitor shows an extraordinary cycleability (5000 cycles with over 80% of capacitance retention. In addition, Li-storage properties of TRGO are also evaluated in half-cell configuration (Li/TRGO and shown to deliver a reversible capacity of ∼705 mAh g–1 with good cycleability at constant current density of 37 mA g–1. This result clearly suggests that green-synthesized graphene can be effectively used as a prospective electrode material for non-aqueous energy storage systems such as Li-ion batteries and supercapacitors.

  2. Basicity comparison for di-substituted 4-nitropyridine derivatives in polar non-aqueous media

    International Nuclear Information System (INIS)

    Gurzynski, Lukasz; Puszko, Aniela; Chmurzynski, Lech

    2007-01-01

    Acid dissociation, as well as cationic homoconjugation equilibria have been studied potentiometrically in systems involving four di-substituted 4-nitropyridines and conjugate cationic acids in the polar non-aqueous solvents - aprotic protophobic acetonitrile (AN) and propylene carbonate (PC), the amphiprotic methanol (MeOH), and in the aprotic protophilic dimethyl sulfoxide (DMSO). The influence of solvent effect on the obtained acidity constants has been discussed. The acidity constants (expressed as pK a values) were compared with those previously determined in another polar protophobic aprotic solvent - acetone (AC), and obtained for the unsubstituted pyridine (Py). A comparison of the acid dissociation constants determined in all media studied has proved that the strength of the cationic acids increases on going from acetonitrile through propylene carbonate, acetone, and methanol to dimethyl sulfoxide. Furthermore, the values of acidity constants in the non-aqueous media have shown that in all the solvents studied they change according to the substituent effects. It has been also found that substituted 4-nitropyridine derivatives studied exhibit no tendency towards cationic homoconjugation in acetonitrile, propylene carbonate, and methanol and dimethyl sulfoxide. Moreover, it has been demonstrated that the acid dissociation constants determined by potentiometric titration method in all the solutions investigated correlate well with the calculated energy parameters of the protonation reactions in the gaseous phase

  3. Basicity comparison for di-substituted 4-nitropyridine derivatives in polar non-aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Gurzynski, Lukasz [Department of General and Inorganic Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Puszko, Aniela [Department of Organic Chemistry, School of Economics, Wroclaw (Poland); Chmurzynski, Lech [Department of General and Inorganic Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland)], E-mail: lech@chemik.chem.univ.gda.pl

    2007-12-15

    Acid dissociation, as well as cationic homoconjugation equilibria have been studied potentiometrically in systems involving four di-substituted 4-nitropyridines and conjugate cationic acids in the polar non-aqueous solvents - aprotic protophobic acetonitrile (AN) and propylene carbonate (PC), the amphiprotic methanol (MeOH), and in the aprotic protophilic dimethyl sulfoxide (DMSO). The influence of solvent effect on the obtained acidity constants has been discussed. The acidity constants (expressed as pK{sub a} values) were compared with those previously determined in another polar protophobic aprotic solvent - acetone (AC), and obtained for the unsubstituted pyridine (Py). A comparison of the acid dissociation constants determined in all media studied has proved that the strength of the cationic acids increases on going from acetonitrile through propylene carbonate, acetone, and methanol to dimethyl sulfoxide. Furthermore, the values of acidity constants in the non-aqueous media have shown that in all the solvents studied they change according to the substituent effects. It has been also found that substituted 4-nitropyridine derivatives studied exhibit no tendency towards cationic homoconjugation in acetonitrile, propylene carbonate, and methanol and dimethyl sulfoxide. Moreover, it has been demonstrated that the acid dissociation constants determined by potentiometric titration method in all the solutions investigated correlate well with the calculated energy parameters of the protonation reactions in the gaseous phase.

  4. A non-aqueous all-copper redox flow battery with highly soluble active species

    International Nuclear Information System (INIS)

    Li, Yun; Sniekers, Jeroen; Malaquias, João; Li, Xianfeng; Schaltin, Stijn; Stappers, Linda; Binnemans, Koen; Fransaer, Jan; Vankelecom, Ivo F.J.

    2017-01-01

    A metal-based redox pair with acetonitrile as ligand [Cu(MeCN)_4][Tf_2N] is described for use in non-aqueous redox flow battery (RFB). The electrode kinetics of the anode and cathode are studied using cyclic voltammetry. The Cu"2"+/Cu"+ and Cu"+/Cu couples in this system yield a cell potential of 1.24 V. The diffusion coefficient for [Cu(MeCN)_4][Tf_2N] in acetonitrile is estimated to be 6.8 × 10"−"6 cm"2 s"−"1 at room temperature. The copper-acetonitrile complex has a very high solubility of 1.68 M in acetonitrile, the most widely used organic solvent for non-aqueous electrochemical applications. Hence, a maximum theoretical energy density around 28 Wh L"−"1 can be reached with the reported system. The RFB with this electrolyte shows a promising performance, with coulombic efficiencies of 87% and energy efficiencies of 44% (5 mA cm"−"2).

  5. EFFECTS OF ROTATIONALLY INDUCED MIXING IN COMPACT BINARY SYSTEMS WITH LOW-MASS SECONDARIES AND IN SINGLE SOLAR-TYPE STARS

    International Nuclear Information System (INIS)

    Chatzopoulos, E.; Robinson, Edward L.; Wheeler, J. Craig

    2012-01-01

    Many population synthesis and stellar evolution studies have addressed the evolution of close binary systems in which the primary is a compact remnant and the secondary is filling its Roche lobe, thus triggering mass transfer. Although tidal locking is expected in such systems, most studies have neglected the rotationally induced mixing that may occur. Here we study the possible effects of mixing in mass-losing stars for a range of secondary star masses and metallicities. We find that tidal locking can induce rotational mixing prior to contact and thus affect the evolution of the secondary star if the effects of the Spruit-Tayler dynamo are included both for angular momentum and chemical transport. Once contact is made, the effect of mass transfer tends to be more rapid than the evolutionary timescale, so the effects of mixing are no longer directly important, but the mass-transfer strips matter to inner layers that may have been affected by the mixing. These effects are enhanced for secondaries of 1-1.2 M ☉ and for lower metallicities. We discuss the possible implications for the paucity of carbon in the secondaries of the cataclysmic variable SS Cyg and the black hole candidate XTE J1118+480 and for the progenitor evolution of Type Ia supernovae. We also address the issue of the origin of blue straggler stars in globular and open clusters. We find that for models that include rotation consistent with that observed for some blue straggler stars, evolution is chemically homogeneous. This leads to tracks in the H-R diagram that are brighter and bluer than the non-rotating main-sequence turn-off point. Rotational mixing could thus be one of the factors that contribute to the formation of blue stragglers.

  6. Improving the treatment of non-aqueous phase TCE in low permeability zones with permanganate

    Energy Technology Data Exchange (ETDEWEB)

    Chokejaroenrat, Chanat, E-mail: chanat@sut.ac.th [Department of Civil Engineering, University of Nebraska, Lincoln, NE 68588-0531 (United States); School of Environmental Engineering, Institute of Engineering, Suranaree University of Technology, Nakhon Ratchasima 30000 (Thailand); Comfort, Steve, E-mail: scomfort1@unl.edu [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Sakulthaew, Chainarong, E-mail: cvtcns@ku.ac.th [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Department of Veterinary Technology, Kasetsart University, Bangkok 10900 (Thailand); Dvorak, Bruce, E-mail: bdvorak1@unl.edu [Department of Civil Engineering, University of Nebraska, Lincoln, NE 68588-0531 (United States)

    2014-03-01

    Graphical abstract: - Highlights: • Transport experiments used transmissive and low permeability zones (LPZs). • {sup 14}C-labeled TCE was used to quantify oxidation of DNAPL in LPZs by permanganate. • Stabilization aids prevented MnO{sub 2} rind formation. • DNAPL oxidation improved when xanthan and stabilization aids were used. - Abstract: Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is a particularly challenging issue for injection-based remedial treatments. Our objective was to improve the sweeping efficiency of permanganate (MnO{sub 4}{sup −}) into LPZs to treat high concentrations of TCE. This was accomplished by conducting transport experiments that quantified the penetration of various permanganate flooding solutions into a LPZ that was spiked with non-aqueous phase {sup 14}C-TCE. The treatments we evaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilization aids that minimized MnO{sub 2} rind formation and (iii) a phase-transfer catalyst. In addition, we quantified the ability of these flooding solutions to improve TCE destruction under batch conditions by developing miniature LPZ cylinders that were spiked with {sup 14}C-TCE. Transport experiments showed that MnO{sub 4}{sup −} alone was inefficient in penetrating the LPZ and reacting with non-aqueous phase TCE, due to a distinct and large MnO{sub 2} rind that inhibited the TCE from further oxidant contact. By including xanthan with MnO{sub 4}{sup −}, the sweeping efficiency increased (90%) but rind formation was still evident. By including the stabilization aid, sodium hexametaphosphate (SHMP) with xanthan, permanganate penetrated 100% of the LPZ, no rind was observed, and the percentage of TCE oxidized increased. Batch experiments using LPZ cylinders allowed longer contact times between the flooding solutions and the DNAPL and results showed that SHMP + MnO{sub 4}{sup −} improved TCE destruction by

  7. Improving the treatment of non-aqueous phase TCE in low permeability zones with permanganate

    International Nuclear Information System (INIS)

    Chokejaroenrat, Chanat; Comfort, Steve; Sakulthaew, Chainarong; Dvorak, Bruce

    2014-01-01

    Graphical abstract: - Highlights: • Transport experiments used transmissive and low permeability zones (LPZs). • 14 C-labeled TCE was used to quantify oxidation of DNAPL in LPZs by permanganate. • Stabilization aids prevented MnO 2 rind formation. • DNAPL oxidation improved when xanthan and stabilization aids were used. - Abstract: Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is a particularly challenging issue for injection-based remedial treatments. Our objective was to improve the sweeping efficiency of permanganate (MnO 4 − ) into LPZs to treat high concentrations of TCE. This was accomplished by conducting transport experiments that quantified the penetration of various permanganate flooding solutions into a LPZ that was spiked with non-aqueous phase 14 C-TCE. The treatments we evaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilization aids that minimized MnO 2 rind formation and (iii) a phase-transfer catalyst. In addition, we quantified the ability of these flooding solutions to improve TCE destruction under batch conditions by developing miniature LPZ cylinders that were spiked with 14 C-TCE. Transport experiments showed that MnO 4 − alone was inefficient in penetrating the LPZ and reacting with non-aqueous phase TCE, due to a distinct and large MnO 2 rind that inhibited the TCE from further oxidant contact. By including xanthan with MnO 4 − , the sweeping efficiency increased (90%) but rind formation was still evident. By including the stabilization aid, sodium hexametaphosphate (SHMP) with xanthan, permanganate penetrated 100% of the LPZ, no rind was observed, and the percentage of TCE oxidized increased. Batch experiments using LPZ cylinders allowed longer contact times between the flooding solutions and the DNAPL and results showed that SHMP + MnO 4 − improved TCE destruction by ∼16% over MnO 4 − alone (56.5% vs. 40.1%). These results support

  8. Development of technology and equipment for manufacturing fluorides rare-earths via non-aqueous method

    International Nuclear Information System (INIS)

    Chatalov, V.V.; Kozlov, O.I.; Machirev, V.P.; Zvonarev, E.N.

    1998-01-01

    Full text: The works on technology and equipment for rare earths (RE) fluorides are very scarce. Presently RE-fluorides are manufactured by various methods. Conventionally they can be divided into two main groups. The first group comprises methods based on precipitation of fluorides from soluble salts of corresponding metals by fluohydric acid (aqueous methods) with following thermal decomposition of aquatic fluorides obtained until anhydric state is reached. The second group (called dry, gaseous or non-aqueous) comprises methods based on direct fluorizating (by fluorine hydride, fluor or other fluorating agents) have several important advantages compared to the aqueous methods: the fluorides obtained are anhydrous; the operations of fluoride precipitation, washing, decantation, filtration are excluded as well as their drying and calcination. The process of calcination is, as a rule, accompanied by pyrohydrolysis. The products manufactured by precipitation are inferior to those obtained by the non-aqueous technique. The world production practice uses both groups of methods. Nevertheless, the method of gaseous hydrofluorination is preferable. In all non-aqueous processes the initial materials are oxides RE which interact with gaseous fluorine hydride. The initial materials - oxides are obtained by thermal decomposition of carbonates, hydroxides, oxalates and so on. One of the best type of apparatus for thermal decomposition processes is a horizontal ring shaped vibrating apparatus with direct heating. The RE - fluorides is synthesized by way of RE-oxide interacting with hydrogen fluoride at 200-550 deg C in single continuous operation: (RE) 2 O 3 + 6 HF → 2 (RE)F 3 + 3 H 2 0 The apparatus consists of a nickel horizontal two tube screw. Reaction time is varied from 2 to 6 hours; the productivity of reactor is defined by feed screw rotation and initial material bulk density. Hydrogen fluoride was passing the reactor opposite to the solid phase. The degree

  9. Improved oral bioavailability and therapeutic efficacy of dabigatran etexilate via Soluplus-TPGS binary mixed micelles system.

    Science.gov (United States)

    Hu, Mei; Zhang, Jinjie; Ding, Rui; Fu, Yao; Gong, Tao; Zhang, Zhirong

    2017-04-01

    The clinical use of dabigatran etexilate (DABE) is limited by its poor absorption and relatively low bioavailability. Our study aimed to explore the potential of a mixed micelle system composed of Soluplus ® and D-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) to improve the oral absorption and bioavailability of DBAE. DBAE was first encapsulated into Soluplus/TPGS mixed micelles by a simple thin film hydration method. The DBAE loaded micelles displayed an average size distribution of around 83.13 nm. The cellular uptake of DBAE loaded micelles in Caco-2 cell monolayer was significantly enhanced by 2-2.6 fold over time as compared with DBAE suspension. Both lipid raft/caveolae and macropinocytosis-mediated the cell uptake of DBAE loaded micelles through P-glycoprotein (P-gp)-independent pathway. Compared with the DBAE suspension, the intestinal absorption of DBAE from DBAE mixed micelles in rats was significantly improved by 8 and 5-fold in ileum at 2 h and 4 h, respectively. Moreover, DBAE mixed micelles were absorbed into systemic circulation via both portal vein and lymphatic pathway. The oral bioavailability of DBAE mixed micelles in rats was 3.37 fold higher than that of DBAE suspension. DBAE mixed micelles exhibited a comparable anti-thrombolytic activity with a thrombosis inhibition rate of 63.18% compared with DBAE suspension in vivo. Thus, our study provides a promising drug delivery system to enhance the oral bioavailability and therapeutic efficacy of DBAE.

  10. Quantifying sediment-associated metal dispersal using Pb isotopes: Application of binary and multivariate mixing models at the catchment-scale

    International Nuclear Information System (INIS)

    Bird, Graham; Brewer, Paul A.; Macklin, Mark G.; Nikolova, Mariyana; Kotsev, Tsvetan; Mollov, Mihail; Swain, Catherine

    2010-01-01

    In this study Pb isotope signatures were used to identify the provenance of contaminant metals and establish patterns of downstream sediment dispersal within the River Maritsa catchment, which is impacted by the mining of polymetallic ores. A two-fold modelling approach was undertaken to quantify sediment-associated metal delivery to the Maritsa catchment; employing binary mixing models in tributary systems and a composite fingerprinting and mixing model approach in the wider Maritsa catchment. Composite fingerprints were determined using Pb isotopic and multi-element geochemical data to characterize sediments delivered from tributary catchments. Application of a mixing model allowed a quantification of the percentage contribution of tributary catchments to the sediment load of the River Maritsa. Sediment delivery from tributaries directly affected by mining activity contributes 42-63% to the sediment load of the River Maritsa, with best-fit regression relationships indicating that sediments originating from mining-affected tributaries are being dispersed over 200 km downstream. - Pb isotopic evidence used to quantify sediment-associated metal delivery within a mining-affected river catchment.

  11. Carbon dioxide assist for non-aqueous sodium–oxygen batteries

    KAUST Repository

    Das, Shyamal K.

    2013-02-01

    We report a novel non-aqueous Na-air battery that utilizes a gas mixture of CO2 and O2. The battery exhibits a high specific energy of 6500-7000 Whkg- 1 (based on the carbon mass) over a range of CO2 feed compositions. The energy density achieved is higher, by 200% to 300%, than that obtained in pure oxygen. Ex-situ FTIR and XRD analysis reveal that Na2O2, Na2C2O 4 and Na2CO3 are the principal discharge products. The Na-CO2/O2 and Mg-CO2/O 2 battery platforms provide a promising, new approach for CO 2 capture and generation of electrical energy. © 2012 Elsevier B.V. All rights reserved.

  12. Cross-linked PAN-based thin-film composite membranes for non-aqueous nanofiltration

    KAUST Repository

    Pérez-Manríquez, Liliana

    2015-01-01

    A new approach on the development of cross-linked PAN based thin film composite (TFC) membranes for non-aqueous application is presented in this work. Polypropylene backed neat PAN membranes fabricated by phase inversion process were cross-linked with hydrazine to get excellent solvent stability toward dimethylformamide (DMF). By interfacial polymerization a selective polyamide active layer was coated over the cross-linked PAN using N,N′-diamino piperazine (DAP) and trimesoyl chloride (TMC) as monomers. Permeation and molecular weight cut off (MWCO) experiments using various dyes were done to evaluate the performance of the membranes. Membranes developed by such method show excellent solvent stability toward DMF with a permeance of 1.7 L/m2 h bar and a molecular weight cut-off of less than 600 Da.

  13. Radiation-induced changes of liposomes and lecithin in non-aqueous media

    International Nuclear Information System (INIS)

    Nakazawa, T.; Nagatsuka, S.; Sakurai, T.

    1981-01-01

    Radiation-induced changes of lipids in non-aqueous media were studied to elucidate the process of radiation damage in biological membranes. The lipid peroxidation progressed linearly with increasing dose and decreasing dose rate of γ-irradiation in soyabean lecithin in chloroform. The fatty acid composition of lecithin also changed, especially in linoleic and linolenic acids. Lower dose rate radiation enhanced these changes in oxic condition. Lipid peroxidation was also shown in lipids extracted from irradiated liposomes or in liposomes prepared from irradiated lecithin in chloroform. The dose-dependent glucose efflux was seen in liposomes prepared from irradiated lecithin in chloroform. These results indicate that the peroxidation of lipid molecules might cause radiation damage to the membrane conformation. (author)

  14. Studies of the reactions of uranium pentabromide and hexabromouranate(V) in non-aqueous solvents

    International Nuclear Information System (INIS)

    Dehos, R.F.

    1984-01-01

    With the help of IR and electron spectra, the behaviour of uranium pentabromide and hexabromo uranate in non-aqueous nitromethane, nitroethane, bromine, dichlormethane, dibromomethane and acetonitrile was studied. By comparison of the spectra of the solutions in nitromethane with the solutions using other solvents on one side, and on the other side with the solids spectra of the end products, the redox reactions of the uranium V in nitromethane solutions could be more than clarified. Studies were also carried out on the time-dependency of the uranium IV and uranium V contents of the solutions at room temperature and at -20 0 C. The existence of the HUBr 6 which probably appears as an intermediate product was tested in another experiment. First evidence for the existence of UBr 6 as a disproportionation product of UBr 5 were achieved by tests in solutions of acetonitrile at -47 0 C. (RB) [de

  15. The effect of non-aqueous solvents on spectrophotometric analysis of lead (II)

    International Nuclear Information System (INIS)

    Ramadan, A.A.; Bahbouh, M.; Kamuah, M.

    1992-01-01

    The effect of the following non-aqueous solvents: Methanol, Ethanol, Propanol, iso-propanol, dimethylsulfoxide, dimethylformamide and acetonitrile on spectrophotometric analysis of lead (II) was studied. One absorption peak at range 220-340 nm was observed. The values of maximum wave length (λ max ) and maximum molar absorptivity coefficient (ε max ) vary in accordance with the above solvents and the concentration of HC1. the analytical curves, A=f(C Pb 2+ ), for the determination of lead (II) in presence 5 M HC1 (in methanol) and 7 M HC1 (in other solvents) showed linear proportionality over the concentration range 2.5x10 -5 - 2.0x10 -4 M Pb 2+ . (author). 16 Refs., 4 figs., 2 Tabs

  16. A chromatographic determination of water in non-aqueous phases of solvent extraction systems

    International Nuclear Information System (INIS)

    Lyle, S.J.; Smith, D.B.

    1975-01-01

    The disadvantages of the Karl Fischer method for the determination of water in the non-aqueous phases of solvent extraction systems are pointed out, and a gas chromatographic method is described which is claimed to be potentially capable of overcoming these disadvantages. The method, as described, was developed to satisfy conditions relevant to measurement of the transfer rate of water from an aqueous phase into tri-n-butylphosphate in toluene, but it can be used for water determination in other solvent extraction systems. The apparatus used is described in detail. The concentration of water in water-saturated TBP was found to be 3.56 mol/litre, compared with a value of 3.55 obtained by Karl Fischer titration and previous literature values of 3.59 and 3.57. Measurements of water content in benzene solutions of long chain alkylamines were also sucessfully carried out. (U.K.)

  17. Alkaline and non-aqueous proton-conducting pouch-cell batteries

    Science.gov (United States)

    Young, Kwo-hsiung; Nei, Jean; Meng, Tiejun

    2018-01-02

    Provided are sealed pouch-cell batteries that are alkaline batteries or non-aqueous proton-conducing batteries. A pouch cell includes a flexible housing such as is used for pouch cell construction where the housing is in the form of a pouch, a cathode comprising a cathode active material suitable for use in an alkaline battery, an anode comprising an anode active material suitable for use in an alkaline battery, an electrolyte that is optionally an alkaline or proton-conducting electrolyte, and wherein the pouch does not include or require a safety vent or other gas absorbing or releasing system as the anode active material and the cathode active material do not increase the internal atmospheric pressure any more than 2 psig during cycling. The batteries provided function contrary to the art recognized belief that such battery systems were impossible due to unacceptable gas production during cycling.

  18. Influence of clay, surfactant and presence of dispersant in the non-aqueous fluids rheology

    International Nuclear Information System (INIS)

    Gomes, N.L.; Guedes, I.C.; Menezes, R.R.; Campos, L.F.A.; Ferreira, H.S.

    2012-01-01

    The bentonite clay used as a thickening agent in production of non-aqueous fluids and can not be used without a prior treatment to their organic surfaces become hydrophobic. These treated clays are called organoclays, and are usually obtained by adding, in aqueous solution, a quaternary ammonium salt. This work makes a detailed study of the variables involved in the dispersion of the bentonite clays in organophilization process, as well, the type of clay, type of surfactant and the presence of dispersant. It was observed this study that the process variables involved in the dispersion of the clays and organophilization, observed through characterization, have low influence on the peaks related to interplanar basal distance caused by the incorporation of the surfactant and bentonite clays been influential the type of clay and surfactant and the presence of sodium as dispersant agent, on the rheological properties. (author)

  19. Enhancing the stability and performance of a battery cathode using a non-aqueous electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Yeol [Division of Engineering, Brown University, Providence, RI 02912 (United States); Sen, Sujat [Department of Chemistry, Brown University, Providence, RI 02912 (United States); Song, Hyun-Kon [Interdisciplinary School of Green Energy and School of Nano-Biotechnology and Chemical Engineering, Ulsan National Institute of Science and Technology, Banyeon-ri 100, Ulju-gun, Ulsan 689-798 (Korea); Palmore, G. Tayhas R. [Division of Biology and Medicine, Brown University, Providence, RI 02912 (United States)

    2010-06-15

    For conductive polymers to be considered materials for energy storage, both their electroactivity and stability must be optimized. In this study, a non-aqueous electrolyte (0.2 M LiClO{sub 4} in acetonitrile) was studied for its effect on the charge storage capacity and stability of two materials used in batteries developed in our laboratory, polypyrrole (pPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) doped with 2,2'-azino-bis(3-ethylbenzothiaxoline-6-sulfonic acid (ABTS)). The results are compared to the performance of these materials in an aqueous electrolyte (0.2 M HCl/aq). Loss of ABTS dopant was eliminated principally due to the low solubility of ABTS in acetonitrile, resulting in cathode materials with improved stability in terms of load cycling and performance. (author)

  20. Ion Movement in Polypyrrole/Dodecylbenzenesulphonate Films in aqueous and non-aqueous electrolytes

    DEFF Research Database (Denmark)

    Vidanapathirana, K.; Careem, M.A.; Skaarup, Steen

    2002-01-01

    The electrochemical characteristics during the redox process of polypyrrole (PPy) films, prepared using dodecylbenzenesulphonate (DBS-) dopant species, have been investigated using a combination of cyclic voltammetry and Electrochemical Quartz Crystal Microbalance (EQCM) measurements. Investigati......The electrochemical characteristics during the redox process of polypyrrole (PPy) films, prepared using dodecylbenzenesulphonate (DBS-) dopant species, have been investigated using a combination of cyclic voltammetry and Electrochemical Quartz Crystal Microbalance (EQCM) measurements....... Investigations were carried out using aqueous and non-aqueous electrolytes to study the effect of solvent on the ion movement during redox processes. When PPy films are cycled in aqueous electrolytes transport of both anion and cation occurs during oxidation and reduction. However, when cycled in the nonaqueous...

  1. Molecular dynamics investigation of carbon nanotube junctions in non-aqueous solutions

    KAUST Repository

    Gkionis, Konstantinos

    2014-07-23

    The properties of liquids in a confined environment are known to differ from those in the bulk. Extending this knowledge to geometries defined by two metallic layers in contact with the ends of a carbon nanotube is important for describing a large class of nanodevices that operate in non-aqueous environments. Here we report a series of classical molecular dynamics simulations for gold-electrode junctions in acetone, cyclohexane and N,N-dimethylformamide solutions and analyze the structure and the dynamics of the solvents in different regions of the nanojunction. The presence of the nanotube has little effect on the ordering of the solvents along its axis, while in the transversal direction deviations are observed. Importantly, the orientational dynamics of the solvents at the electrode-nanotube interface differ dramatically from that found when only the electrodes are present.

  2. High frequency titration in non-aqueous solvents. Application to HF and UF6

    International Nuclear Information System (INIS)

    Neveu, Claude

    1965-01-01

    In this research thesis, the author first presents the main theoretical notions regarding high frequency titration, notably by studying characteristic curves, i.e. the titration meter indication with respect to conductibility. He reports the use of this method for the study of various reactions in non-aqueous medium: reaction of AlCl 3 with pyridine in acetonitrile, of AlCl 3 with HCl in tetrachloroethane and in nitromethane. He also reports the attempt of application of this method to the titration of HF in presence of UF 6 in CCl 4 as solvent, or by using F acceptors like BF 3 , PF 5 or ClF 3 as reactants [fr

  3. Ferrocene and cobaltocene derivatives for non-aqueous redox flow batteries.

    Science.gov (United States)

    Hwang, Byunghyun; Park, Min-Sik; Kim, Ketack

    2015-01-01

    Ferrocene and cobaltocene and their derivatives are studied as new redox materials for redox flow cells. Their high reaction rates and moderate solubility are attractive properties for their use as active materials. The cyclability experiments are carried out in a static cell; the results showed that these materials exhibit stable capacity retention and predictable discharge potentials, which agree with the potential values from the cyclic voltammograms. The diffusion coefficients of these materials are 2 to 7 times higher than those of other non-aqueous materials such as vanadium acetylacetonate, iron tris(2,2'-bipyridine) complexes, and an organic benzene derivative. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Mixed-symmetry localized modes and breathers in binary mixtures of Bose-Einstein condensates in optical lattices

    International Nuclear Information System (INIS)

    Cruz, H. A.; Brazhnyi, V. A.; Konotop, V. V.; Alfimov, G. L.; Salerno, M.

    2007-01-01

    We study localized modes in binary mixtures of Bose-Einstein condensates embedded in one-dimensional optical lattices. We report a diversity of asymmetric modes and investigate their dynamics. We concentrate on the cases where one of the components is dominant, i.e., has a much larger number of atoms than the other one, and where both components have the numbers of atoms of the same order but different symmetries. In the first case we propose a method of systematically obtaining the modes, considering the ''small'' component as bifurcating from the continuum spectrum. A generalization of this approach combined with the use of the symmetry of the coupled Gross-Pitaevskii equations allows for obtaining breather modes, which are also presented

  5. Formation of self-assembled quantum dots of iron oxide thin films by spray pyrolysis from non-aqueous medium

    International Nuclear Information System (INIS)

    Desai, J.D.; Pathan, H.M.; Min, Sun-Ki; Jung, Kwang-Deog; Joo, Oh-Shim

    2006-01-01

    Quantum dots (QDs) of iron oxide have been deposited onto ITO coated glass substrates by spray pyrolysis technique, using ferric chloride (FeCl 3 .7H 2 O) in non-aqueous medium as a starting material. The non-aqueous solvents namely methanol, ethanol, propanol, butanol and pentanol were used as solvents. The effect of solvents on the film structure and morphology was studied. The structural, morphological, compositional and optical properties were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), and optical absorption measurement techniques

  6. Interacting binaries

    International Nuclear Information System (INIS)

    Eggleton, P.P.; Pringle, J.E.

    1985-01-01

    This volume contains 15 review articles in the field of binary stars. The subjects reviewed span considerably, from the shortest period of interacting binaries to the longest, symbiotic stars. Also included are articles on Algols, X-ray binaries and Wolf-Rayet stars (single and binary). Contents: Preface. List of Participants. Activity of Contact Binary Systems. Wolf-Rayet Stars and Binarity. Symbiotic Stars. Massive X-ray Binaries. Stars that go Hump in the Night: The SU UMa Stars. Interacting Binaries - Summing Up

  7. High-activity MgO-supported CoMo Hydrodesulfurization Catalysts Prepared by Non-aqueous Impregnation

    Czech Academy of Sciences Publication Activity Database

    Kaluža, Luděk; Gulková, Daniela; Vít, Zdeněk; Zdražil, Miroslav

    2015-01-01

    Roč. 162, JAN 2015 (2015), s. 430-436 ISSN 0926-3373 R&D Projects: GA ČR GAP106/11/0902 Institutional support: RVO:67985858 Keywords : CoMo/MgO * benzothiophene hydrodesulfurization * non-aqueous impregnation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 8.328, year: 2015

  8. Potential of mean force for ion pairs in non-aqueous solvents. Comparison of polarizable and non-polarizable MD simulations

    Science.gov (United States)

    Odinokov, A. V.; Leontyev, I. V.; Basilevsky, M. V.; Petrov, N. Ch.

    2011-01-01

    Potentials of mean force (PMF) are calculated for two model ion pairs in two non-aqueous solvents. Standard non-polarizable molecular dynamics simulation (NPMD) and approximate polarizable simulation (PMD) are implemented and compared as tools for monitoring PMF profiles. For the polar solvent (dimethylsulfoxide, DMSO) the PMF generated in terms of the NPMD reproduces fairly well the refined PMD-PMF profile. For the non-polar solvent (benzene) the conventional NPMD computation proves to be deficient. The validity of the correction found in terms of the approximate PMD approach is verified by its comparison with the result of the explicit PMD computation in benzene. The shapes of the PMF profiles in DMSO and in benzene are quite different. In DMSO, owing to dielectric screening, the PMF presents a flat plot with a shallow minimum positioned in the vicinity of the van der Waals contact of the ion pair. For the benzene case, the observed minimum proves to be unexpectedly deep, which manifests the formation of a tightly-binded contact ion pair. This remarkable effect arises owing to the strong electrostatic interaction that is incompletely screened by a non-polar medium. The PMFs for the binary benzene/DMSO mixtures display intermediate behaviour depending on the DMSO content.

  9. pKa values of hyodeoxycholic and cholic acids in the binary mixed micelles sodium-hyodeoxycholate-Tween 40 and sodium-cholate-Tween 40: Thermodynamic stability of the micelle and the cooperative hydrogen bond formation with the steroid skeleton.

    Science.gov (United States)

    Poša, Mihalj; Pilipović, Ana; Bećarević, Mirjana; Farkaš, Zita

    2017-01-01

    Due to a relatively small size of bile acid salts, their mixed micelles with nonionic surfactants are analysed. Of the special interests are real binary mixed micelles that are thermodynamically more stable than ideal mixed micelles. Thermodynamic stability is expressed with an excess Gibbs energy (G E ) or over an interaction parameter (β ij ). In this paper sodium salts of cholic (C) and hyodeoxycholic acid (HD) in their mixed micelles with Tween 40 (T40) are analysed by potentiometric titration and their pKa values are determined. Examined bile acids in mixed micelles with T40 have higher pKa values than free bile acids. The increase of ΔpKa acid constant of micellary bound C and HD is in a correlation with absolute values of an interaction parameter. According to an interaction parameter and an excess Gibbs energy, mixed micelle HD-T40 are thermodynamically more stable than mixed micelles C-T40. ΔpKa values are higher for mixed micelles with Tween 40 whose second building unit is HD, related to the building unit C. In both micellar systems, ΔpKa increases with the rise of a molar fraction of Tween 40 in binary mixtures of surfactants with sodium salts of bile acids. This suggests that, ΔpKa can be a measure of a thermodynamic stabilization of analysed binary mixed micelles as well as an interaction parameter. ΔpKa values are confirmed by determination of a distribution coefficient of HD and C in systems: water phase with Tween 40 in a micellar concentration and 1-octanol, with a change of a pH value of a water phase. Conformational analyses suggests that synergistic interactions between building units of analysed binary micelles originates from formation of hydrogen bonds between steroid OH groups and polyoxyethylene groups of the T40. Relative similarity and spatial orientation of C 3 and C 6 OH group allows cooperative formation of hydrogen bonds between T40 and HD - excess entropy in formation of mixed micelle. If a water solution of analysed binary

  10. Infiltration characteristics of non-aqueous phase liquids in undisturbed loessal soil cores

    Institute of Scientific and Technical Information of China (English)

    WANG Yunqiang; SHAO Ming'an

    2009-01-01

    The widespread contamination of soils and aquifers by non-aqueous phase liquids (NAPL), such as crude oil, poses serious environmental and health hazards globally. Understanding the infiltration characteristics of NAPL in soil is crucial in mitigating or remediating soil contamination. The infiltration characteristics of crude and diesel oils into undisturbed loessal soil cores, collected in polymethyl methacrylate cylindrical columns, were investigated under a constant fluid head (3 cm) of either crude oil or diesel oil. The infiltration rate of both crude and diesel oils decreased exponentially as wetting depth increased with time. Soil core size and bulk density both had a significant effect on NAPL infiltration through the undisturbed soil cores; a smaller core size or a greater bulk density both reduced oil penetration to depth. Compacting soil in areas susceptible to oil spills may be an effective way to reduce contamination. The infiltration of NAPL into soil cores was spatially anisotropic and heterogeneous, thus recording the data at four points on the soil core is a good way to improve the accuracy of experimental results. Our results provided information about crude and diesel oils, rather than their components, and may have practical value for remediation of contaminated loessal soils.

  11. Molecular dynamics simulation of cyclodextrin aggregation and extraction of Anthracene from non-aqueous liquid phase

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xinzhe [Shenzhen Key Laboratory for Coastal Ocean Dynamic and Environment, Division of Ocean Science and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); School of Environment, Tsinghua University, Beijing 100084 (China); Wu, Guozhong [Shenzhen Key Laboratory for Coastal Ocean Dynamic and Environment, Division of Ocean Science and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Chen, Daoyi, E-mail: chen.daoyi@sz.tsinghua.edu.cn [Shenzhen Key Laboratory for Coastal Ocean Dynamic and Environment, Division of Ocean Science and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China)

    2016-12-15

    Cyclodextrin (CD) extraction is widely used for the remediation of polycyclic aromatic hydrocarbons (PAH) pollution, but it remains unclear about the influence of CD aggregation on the PAH transport from non-aqueous liquid phase to water. The atomistic adsorption and complexation of PAHs (32 anthracenes) by CD aggregates (48 β-cyclodextrins) were studied by molecular dynamics simulations at hundreds of nanoseconds time scale. Results indicated that high temperature promoted the βCD aggregation in bulk oil, which was not found in bulk water. Nevertheless, the fractions of anthracenes entrapped inside the βCDs cavity in both scenarios were significantly increased when temperature increased from 298 to 328 K. Free energy calculation for the sub-steps of CD extraction demonstrated that the anthracenes could be extracted when the βCDs arrived at the water-oil interface or after the βCDs entered the bulk oil. The former was kinetic-controlled while the latter was thermodynamic-limited process. Results also highlighted the formation of porous structures by CD aggregates in water, which was able to sequestrate PAH clusters with the size obviously larger than the cavity diameter of individual CD. This provided an opportunity for the extraction of recalcitrant PAHs with molecular size larger than anthracenes by cyclodextrins.

  12. of radioconjugated DOTA-1-Nal3-octreotide labeled with gallium-68 using non-aqueous solvents

    International Nuclear Information System (INIS)

    Pérez-Malo Cruz, Marylaine; Leyva Montaña, René

    2016-01-01

    Neuroendocrine tumors specifically over-expressing somatostatin receptors. Diagnosis has expanded due to radiolabelling of DOTA-peptides such as somatostatin analogue DOTA-1-Nal 3 -Octreotide (DOTA-NOC) conjugated to β+ emitting radionuclides such as 68 Ga, which has very favorable physics-nuclear properties. This paper describes the radiolabeling procedures of DOTA-NOC with 68 Ga, in pure aqueous medium and in presence of non-aqueous solvents as well as the methods used for quality control where a formulation is obtained with a radiochemical yield exceeding 95%. The addition of ethanol (30% - v / v) to reaction mixture allowed to increase the specific activity of 68 Ga-DOTA-NOC radioconjugate, reaching a value of 182 MBq / nmol, higher than reported in the literature (50 MBq / nmol ) for labeling in pure aqueous medium. Stability studies are also presented (in presence of saline solution and saline phosphate buffer, transmetallation studies in Fe 3+ , Ca 2+ , Mg 2+ and Zn 2+ solutions, challenges competition against EDTA and DTPA chelators and in vitro stability in human transferrin) performed to 68Ga-DOTA-NOC radioconjugated, showing its high stability (> 95%). (author)

  13. Containment and recovery of a light non-aqueous phase liquid plume at a woodtreating facility

    International Nuclear Information System (INIS)

    Crouse, D.; Powell, G.; Hawthorn, S.; Weinstock, S.

    1997-01-01

    A woodtreating site in Montana used a formulation (product) of 5 percent pentachlorophenol and 95 percent diesel fuel as a carrier liquid to pressure treat lumber. Through years of operations approximately 378,500 liters of this light non-aqueous phase liquid (LNAPL) product spilled onto the ground and soaked into the groundwater. A plume of this LNAPL product flowed in a northerly direction toward a stream located approximately 410 meters from the pressure treatment building. A 271-meter long high density polyethylene (HDPE) containment cutoff barrier wall was installed 15 meters from the stream to capture, contain, and prevent the product from migrating off site. This barrier was extended to a depth of 3.7 meters below ground surface and allowed the groundwater to flow beneath it. Ten product recovery wells, each with a dual-phase pumping system, were installed within the plume, and a groundwater model was completed to indicate how the plume would be contained by generating a cone of influence at each recovery well. The model indicated that the recovery wells and cutoff barrier wall would contain the plume and prevent further migration. To date, nearly 3 1/2 year's later, approximately 106,000 liters of product have been recovered

  14. Non-Aqueous Titration Method for Determining Suppressor Concentration in the MCU Next Generation Solvent (NGS)

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jones, Daniel H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-10-23

    A non-aqueous titration method has been used for quantifying the suppressor concentration in the MCU solvent hold tank (SHT) monthly samples since the Next Generation Solvent (NGS) was implemented in 2013. The titration method measures the concentration of the NGS suppressor (TiDG) as well as the residual tri-n-octylamine (TOA) that is a carryover from the previous solvent. As the TOA concentration has decreased over time, it has become difficult to resolve the TiDG equivalence point as the TOA equivalence point has moved closer. In recent samples, the TiDG equivalence point could not be resolved, and therefore, the TiDG concentration was determined by subtracting the TOA concentration as measured by semi-volatile organic analysis (SVOA) from the total base concentration as measured by titration. In order to improve the titration method so that the TiDG concentration can be measured directly, without the need for the SVOA data, a new method has been developed that involves spiking of the sample with additional TOA to further separate the two equivalence points in the titration. This method has been demonstrated on four recent SHT samples and comparison to results obtained using the SVOA TOA subtraction method shows good agreement. Therefore, it is recommended that the titration procedure be revised to include the TOA spike addition, and this to become the primary method for quantifying the TiDG.

  15. Nanoscale carbon materials from hydrocarbons pyrolysis: Structure, chemical behavior, utilisation for non-aqueous supercapacitors

    International Nuclear Information System (INIS)

    Savilov, Serguei V.; Strokova, Natalia E.; Ivanov, Anton S.; Arkhipova, Ekaterina A.; Desyatov, Andrey V.; Hui, Xia; Aldoshin, Serguei M.; Lunin, Valery V.

    2015-01-01

    Highlights: • N-doped and regular carbon nanomaterials were obtained by pyrolitic technique. • Dynamic vapor sorption of different solvents reveals smaller S BET values. • Steric hindrance and specific chemical interactions are the reasons for this. • Nitrogen doping leads to raise of capacitance and coulombic efficiency with non-aqueous N-containing electrolyte. - Abstract: This work systematically studies adsorption properties of carbon nanomaterials that are synthesized through hydrocarbons that is a powerful technique to fabricate different kinds of carbon materials, e.g., nanotubes, nanoshells, onions, including nitrogen substituted. The adsorption properties of the as-synthesized carbons are achieved by low temperature nitrogen adsorption and organic vapors sorption. Heptane, acetonitrile, water, ethanol, benzene and 1-methylimidazole, which are of great importance for development of supercapacitors, are used as substrates. It is discovered that while nitrogen adsorption reveals a high specific surface area, this parameter for most of organic compounds is rather small depending not only on the size of its molecule but also on chemical interactions for a pair adsorbent–adsorbate. The experimental values of heat of adsorption for carbon and N-substituted structures, when Coulomb cross-coupling of nitrogen atoms in adsorbent and adsorbate takes place, confirms this supposition

  16. Highly Quantitative Electrochemical Characterization of Non-Aqueous Electrolytes & Solid Electrolyte Interphases

    Energy Technology Data Exchange (ETDEWEB)

    Sergiy V. Sazhin; Kevin L. Gering; Mason K. Harrup; Harry W. Rollins

    2012-10-01

    The methods to measure solid electrolyte interphase (SEI) electrochemical properties and SEI formation capability of non-aqueous electrolyte solutions are not adequately addressed in the literature. And yet, there is a strong demand in new electrolyte generations that promote stabilized SEIs and have an influence to resolve safety, calendar life and other limitations of Li-ion batteries. To fill this gap, in situ electrochemical approach with new descriptive criteria for highly quantitative characterization of SEI and electrolytes is proposed. These criteria are: SEI formation capacity, SEI corrosion rate, SEI maintenance rate, and SEI kinetic stability. These criteria are associated with battery parameters like irreversible capacity, self-discharge, shelf-life, power, etc. Therefore, they are especially useful for electrolyte development and standard fast screening, allowing a skillful approach to narrow down the search for the best electrolyte. The characterization protocol also allows retrieving information on interfacial resistance for SEI layers and the electrochemical window of electrolytes, the other important metrics of characterization. The method validation was done on electrolyte blends containing phosphazenes, developed at Idaho National Laboratory, as 1.2M LiPF6 [80 % EC-MEC (2:8) (v/v) + 20% Phosphazene variety] (v/v), which were targeted for safer electrolyte variations.

  17. Non-Aqueous Titration Method for Determining Suppressor Concentration in the MCU Next Generation Solvent (NGS)

    International Nuclear Information System (INIS)

    Taylor-Pashow, Kathryn M. L.; Jones, Daniel H.

    2017-01-01

    A non-aqueous titration method has been used for quantifying the suppressor concentration in the MCU solvent hold tank (SHT) monthly samples since the Next Generation Solvent (NGS) was implemented in 2013. The titration method measures the concentration of the NGS suppressor (TiDG) as well as the residual tri-n-octylamine (TOA) that is a carryover from the previous solvent. As the TOA concentration has decreased over time, it has become difficult to resolve the TiDG equivalence point as the TOA equivalence point has moved closer. In recent samples, the TiDG equivalence point could not be resolved, and therefore, the TiDG concentration was determined by subtracting the TOA concentration as measured by semi-volatile organic analysis (SVOA) from the total base concentration as measured by titration. In order to improve the titration method so that the TiDG concentration can be measured directly, without the need for the SVOA data, a new method has been developed that involves spiking of the sample with additional TOA to further separate the two equivalence points in the titration. This method has been demonstrated on four recent SHT samples and comparison to results obtained using the SVOA TOA subtraction method shows good agreement. Therefore, it is recommended that the titration procedure be revised to include the TOA spike addition, and this to become the primary method for quantifying the TiDG.

  18. Infiltration characteristics of non-aqueous phase liquids in undisturbed loessal soil cores.

    Science.gov (United States)

    Wang, Yunqiang; Shao, Ming'an

    2009-01-01

    The widespread contamination of soils and aquifers by non-aqueous phase liquids (NAPL), such as crude oil, poses serious environmental and health hazards globally. Understanding the infiltration characteristics of NAPL in soil is crucial in mitigating or remediating soil contamination. The infiltration characteristics of crude and diesel oils into undisturbed loessal soil cores, collected in polymethyl methacrylate cylindrical columns, were investigated under a constant fluid head (3 cm) of either crude oil or diesel oil. The infiltration rate of both crude and diesel oils decreased exponentially as wetting depth increased with time. Soil core size and bulk density both had significant effects on NAPL infiltration through the undisturbed soil cores; a smaller core size or a greater bulk density could reduce oil penetration to depth. Compacting soil in areas susceptible to oil spills may be an effective stratage to reduce contamination. The infiltration of NAPL into soil cores was spatially anisotropic and heterogeneous, thus recording the data at four points on the soil core is a good stratage to improve the accuracy of experimental results. Our results revealed that crude and diesel oils, rather than their components, have a practical value for remediation of contaminated loessal soils.

  19. Expanded separation technique for chlorophyll metabolites in Oriental tobacco leaf using non aqueous reversed phase chromatography.

    Science.gov (United States)

    Ishida, Naoyuki

    2011-08-26

    An improved separation method for chlorophyll metabolites in Oriental tobacco leaf was developed. While Oriental leaf still gives the green color even after the curing process, little attention has been paid to the detailed composition of the remaining green pigments. This study aimed to identify the green pigments using non aqueous reversed phase chromatography (NARPC). To this end, liquid chromatograph (LC) equipped with a photo diode array detector (DAD) and an atmospheric pressure chemical ionization/mass spectrometer (APCI/MSD) was selected, because it is useful for detecting low polar non-volatile compounds giving green color such as pheophytin a. Identification was based on the wavelength spectrum, mass spectrum and retention time, comparing the analytes in Oriental leaf with the commercially available and synthesized components. Consequently, several chlorophyll metabolites such as hydroxypheophytin a, solanesyl pheophorbide a and solanesyl hydroxypheophorbide a were newly identified, in addition to typical green pigments such as chlorophyll a and pheophytin a. Chlorophyll metabolites bound to solanesol were considered the tobacco specific components. NARPC expanded the number of detectable low polar chlorophyll metabolites in Oriental tobacco leaf. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Isolation of whiskers from natural sources and their dispersed in a non-aqueous medium

    Energy Technology Data Exchange (ETDEWEB)

    Vestena, Mauro; Gross, Idejan Padilha; Pires, Alfredo Tiburcio Nunes; Muller, Carmen Maria Olivera, E-mail: mauro@utfpr.edu.br [Universidade Federal Santa Catarina (UFSC), Florianopolis, SC (Brazil)

    2016-10-15

    Whiskers have been used as a nano material dispersed in polymer matrices to modify the microscopic and macroscopic properties of the polymer. These nanomaterials can be isolated from cellulose, one of the most abundant natural renewable sources of biodegradable polymer. In this study, whiskers were isolated from sugarcane bagasse and corn cob straw fibers. Initially, the cellulose fiber was treated through an alkaline/oxidative process followed by acid hydrolysis. Dimethylformamide and dimethyl sulfoxide were used to replace the aqueous medium for the dispersion of the whiskers. For the solvent exchange, dimethylformamide or dimethyl sulfoxide was added to the aqueous dispersion and the water was then removed by fractional distillation. FTIR, TGA, XRD, TEM, Zeta and DLS techniques were used to evaluate the efficiency of the isolation process as well as the morphology and dimensions of the whiskers. The dimensions of the whiskers are comparable with values reported in the literature, maintaining the uniformity and homogeneity in both aqueous and non-aqueous solvents. (author)

  1. Isolation of whiskers from natural sources and their dispersed in a non-aqueous medium

    Directory of Open Access Journals (Sweden)

    Mauro Vestena

    Full Text Available Abstract Whiskers have been used as a nanomaterial dispersed in polymer matrices to modify the microscopic and macroscopic properties of the polymer. These nanomaterials can be isolated from cellulose, one of the most abundant natural renewable sources of biodegradable polymer. In this study, whiskers were isolated from sugarcane bagasse and corn cob straw fibers. Initially, the cellulose fiber was treated through an alkaline/oxidative process followed by acid hydrolysis. Dimethylformamide and dimethyl sulfoxide were used to replace the aqueous medium for the dispersion of the whiskers. For the solvent exchange, dimethylformamide or dimethyl sulfoxide was added to the aqueous dispersion and the water was then removed by fractional distillation. FTIR, TGA, XRD, TEM, Zeta and DLS techniques were used to evaluate the efficiency of the isolation process as well as the morphology and dimensions of the whiskers. The dimensions of the whiskers are comparable with values reported in the literature, maintaining the uniformity and homogeneity in both aqueous and non-aqueous solvents.

  2. Non-aqueous electrochemical deposition of lead zirconate titanate films for flexible sensor applications

    Science.gov (United States)

    Joseph, Sherin; Kumar, A. V. Ramesh; John, Reji

    2017-11-01

    Lead zirconate titanate (PZT) is one of the most important piezoelectric materials widely used for underwater sensors. However, PZTs are hard and non-compliant and hence there is an overwhelming attention devoted toward making it flexible by preparing films on flexible substrates by different routes. In this work, the electrochemical deposition of composition controlled PZT films over flexible stainless steel (SS) foil substrates using non-aqueous electrolyte dimethyl sulphoxide (DMSO) was carried out. Effects of various key parameters involved in electrochemical deposition process such as current density and time of deposition were studied. It was found that a current density of 25 mA/cm2 for 5 min gave a good film. The morphology and topography evaluation of the films was carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively, which showed a uniform morphology with a surface roughness of 2 nm. The PZT phase formation was studied using X-ray diffraction (XRD) and corroborated with Raman spectroscopic studies. The dielectric constant, dielectric loss, hysteresis and I-V characteristics of the film was evaluated.

  3. Nanoscale carbon materials from hydrocarbons pyrolysis: Structure, chemical behavior, utilisation for non-aqueous supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Savilov, Serguei V., E-mail: savilov@chem.msu.ru [Lomonosov Moscow State University, Chemistry Department (Russian Federation); Strokova, Natalia E.; Ivanov, Anton S.; Arkhipova, Ekaterina A. [Lomonosov Moscow State University, Chemistry Department (Russian Federation); Desyatov, Andrey V. [D. Mendeleyev University of Chemical Technology of Russia (Russian Federation); Hui, Xia [Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology (China); Aldoshin, Serguei M. [Lomonosov Moscow State University, Faculty of Fundamental Physical and Chemical Engineering (Russian Federation); Lunin, Valery V. [Lomonosov Moscow State University, Chemistry Department (Russian Federation)

    2015-09-15

    Highlights: • N-doped and regular carbon nanomaterials were obtained by pyrolitic technique. • Dynamic vapor sorption of different solvents reveals smaller S{sub BET} values. • Steric hindrance and specific chemical interactions are the reasons for this. • Nitrogen doping leads to raise of capacitance and coulombic efficiency with non-aqueous N-containing electrolyte. - Abstract: This work systematically studies adsorption properties of carbon nanomaterials that are synthesized through hydrocarbons that is a powerful technique to fabricate different kinds of carbon materials, e.g., nanotubes, nanoshells, onions, including nitrogen substituted. The adsorption properties of the as-synthesized carbons are achieved by low temperature nitrogen adsorption and organic vapors sorption. Heptane, acetonitrile, water, ethanol, benzene and 1-methylimidazole, which are of great importance for development of supercapacitors, are used as substrates. It is discovered that while nitrogen adsorption reveals a high specific surface area, this parameter for most of organic compounds is rather small depending not only on the size of its molecule but also on chemical interactions for a pair adsorbent–adsorbate. The experimental values of heat of adsorption for carbon and N-substituted structures, when Coulomb cross-coupling of nitrogen atoms in adsorbent and adsorbate takes place, confirms this supposition.

  4. Microtitrimetric determination of a drug content of pharmaceuticals containing olanzapine in non-aqueous medium

    Directory of Open Access Journals (Sweden)

    KANAKAPURA BASAVAIAH

    2009-05-01

    Full Text Available Two simple, rapid, reliable and cost-effective methods based on titrimetry in non-aqueous medium are described for the determination of olanzapine in pharmaceuticals. In these methods, the drug dissolved in the glacial acetic acid was titrated with the acetous perchloric acid with visual and potentiometric end point detection, crystal violet being used as the indicator for visual titration. The methods are applicable over 1-15 mg range of olanzapine. The procedures were applied to determine olanzapine in pharmaceutical products and the results were found to be in a good agreement with those obtained by the reference method. Associated pharmaceutical materials did not interfere. The precision results, expressed by inter-day and intra-day relative standard deviation values, were satisfactory, higher than 2%. The accuracy was satisfactory as well. The methods proved to be suitable for the analysis of olanzapine in bulk drug and in tablets. The accuracy and reliability of the methods were further ascertained by recovery studies via a standard addition technique with percent recoveries in the range 97.51-103.7% with a standard deviation of less than 2%.

  5. Thermodynamic constrains for life based on non-aqueous polar solvents on free-floating planets.

    Science.gov (United States)

    Badescu, Viorel

    2011-02-01

    Free-floating planets (FFPs) might originate either around a star or in solitary fashion. These bodies can retain molecular gases atmospheres which, upon cooling, have basal pressures of tens of bars or more. Pressure-induced opacity of these gases prevents such a body from eliminating its internal radioactive heat and its surface temperature can exceed for a long term the melting temperature of a life-supporting solvent. In this paper two non-aqueous but still polar solvents are considered: hydrogen sulfide and ammonia. Thermodynamic requirements to be fulfilled by a hypothetic gas constituent of a life-supporting FFP's atmosphere are studied. The three gases analyzed here (nitrogen, methane and ethane) are candidates. We show that bodies with ammonia oceans are possible in interstellar space. This may happen on FFPs of (significantly) smaller or larger mass than the Earth. Generally, in case of FFP smaller in size than the Earth, the atmosphere exhibits a convective layer near the surface and a radiative layer at higher altitudes while the atmosphere of FFPs larger in size than Earth does not exhibit a convective layer. The atmosphere mass of a life-hosting FFP of Earth size is two or three orders of magnitude larger than the mass of Earth atmosphere. For FFPs larger than the Earth and specific values of surface pressure and temperature, there are conditions for condensation (in the ethane atmosphere). Some arguments induce the conclusion than the associated surface pressures and temperatures should be treated with caution as appropriate life conditions.

  6. Simulating the ballistic effects of ion irradiation in the binary collision approximation: A first step toward the ion mixing framework

    International Nuclear Information System (INIS)

    Demange, G.; Antoshchenkova, E.; Hayoun, M.; Lunéville, L.; Simeone, D.

    2017-01-01

    Understanding ballistic effects induced by ion beam irradiation can be a key point for controlling and predicting the microstructure of irradiated materials. Meanwhile, the ion mixing framework suggests an average description of displacement cascades may be sufficient to estimate the influence of ballistic relocations on the microstructure. In this work, the BCA code MARLOWE was chosen for its ability to account for the crystal structure of irradiated materials. A first set of simulations was performed on pure copper for energies ranging from 0.5 keV to 20 keV. These simulations were validated using molecular dynamics (MD). A second set of simulations on AgCu irradiated by 1 MeV krypton ions was then carried out using MARLOWE only, as such energy is beyond reach for molecular dynamics. MARLOWE simulations are found to be in good agreement with experimental results, which suggests the predictive potential of the method.

  7. Simulating the ballistic effects of ion irradiation in the binary collision approximation: A first step toward the ion mixing framework

    Energy Technology Data Exchange (ETDEWEB)

    Demange, G., E-mail: gilles.demange@univ-rouen.fr [DEN/MDN/SRMA/LA2M, CEA Saclay, F-91191 Gif-sur-Yvette (France); Antoshchenkova, E. [DEN/MDN/SRMA/LA2M, CEA Saclay, F-91191 Gif-sur-Yvette (France); Hayoun, M. [LSI, École Polytechnique, CNRS, CEA Saclay, Université Paris-Saclay, F-91128 Palaiseau (France); Lunéville, L. [DEN/SERMA/LLPR, CEA Saclay, F-91191 Gif sur Yvette (France); Simeone, D. [DEN/MDN/SRMA/LA2M, CEA Saclay, F-91191 Gif-sur-Yvette (France)

    2017-04-01

    Understanding ballistic effects induced by ion beam irradiation can be a key point for controlling and predicting the microstructure of irradiated materials. Meanwhile, the ion mixing framework suggests an average description of displacement cascades may be sufficient to estimate the influence of ballistic relocations on the microstructure. In this work, the BCA code MARLOWE was chosen for its ability to account for the crystal structure of irradiated materials. A first set of simulations was performed on pure copper for energies ranging from 0.5 keV to 20 keV. These simulations were validated using molecular dynamics (MD). A second set of simulations on AgCu irradiated by 1 MeV krypton ions was then carried out using MARLOWE only, as such energy is beyond reach for molecular dynamics. MARLOWE simulations are found to be in good agreement with experimental results, which suggests the predictive potential of the method.

  8. Network structure control of binary mixed langmuir monolayers of homo-PS and PS-b-P2VP.

    Science.gov (United States)

    Wen, Gangyao

    2010-03-25

    Our recent work showed there existed a composition window for mixed Langmuir monolayers of homopolystyrene (h-PS) and a symmetric diblock copolymer polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) to form necklace-network structures at the air/water interface. In order to study further the possible mechanism and control the network structure (i.e., surface coverage and nanoaggregate diameter), effects of spreading solution concentration and volume, subphase temperature, and transfer pressure on the network structure were studied by the Langmuir monolayer technique and tapping mode atomic force microscopy. With the increase of transfer pressure, there existed a novel nonlinear behavior for the nanoaggregate diameter first to increase, then to decrease, and finally to increase again, while the surface coverage tended to increase step by step. Moreover, with the elevation of temperature, chain motion between the adjoining nanoaggregates tended to be improved and thus the nanoaggregate diameter tended to be more uniform.

  9. Sample size adjustments for varying cluster sizes in cluster randomized trials with binary outcomes analyzed with second-order PQL mixed logistic regression.

    Science.gov (United States)

    Candel, Math J J M; Van Breukelen, Gerard J P

    2010-06-30

    Adjustments of sample size formulas are given for varying cluster sizes in cluster randomized trials with a binary outcome when testing the treatment effect with mixed effects logistic regression using second-order penalized quasi-likelihood estimation (PQL). Starting from first-order marginal quasi-likelihood (MQL) estimation of the treatment effect, the asymptotic relative efficiency of unequal versus equal cluster sizes is derived. A Monte Carlo simulation study shows this asymptotic relative efficiency to be rather accurate for realistic sample sizes, when employing second-order PQL. An approximate, simpler formula is presented to estimate the efficiency loss due to varying cluster sizes when planning a trial. In many cases sampling 14 per cent more clusters is sufficient to repair the efficiency loss due to varying cluster sizes. Since current closed-form formulas for sample size calculation are based on first-order MQL, planning a trial also requires a conversion factor to obtain the variance of the second-order PQL estimator. In a second Monte Carlo study, this conversion factor turned out to be 1.25 at most. (c) 2010 John Wiley & Sons, Ltd.

  10. Luminescence study on solvation of americium(III), curium(III) and several lanthanide(III) ions in nonaqueous and binary mixed solvents

    International Nuclear Information System (INIS)

    Kimura, T.; Nagaishi, R.; Kato, Y.; Yoshida, Z.

    2001-01-01

    The luminescence lifetimes of An(III) and Ln(III) ions [An=Am and Cm; Ln=Nd, Sm, Eu, Tb and Dy] were measured in dimethyl sulfoxide(DMSO), N,N-dimethylformamide(DMF), methanol(MeOH), water and their perdeuterated solvents. Nonradiative decay rates of the ions were in the order of H 2 O > MeOH > DMF > DMSO, indicating that O-H vibration is more effective quencher than C-H, C=O, and S=O vibrations in the solvent molecules. Maximal lifetime ratios τ D /τ H were observed for Eu(III) in H 2 O, for Sm(III) in MeOH and DMF, and for Sm(III) and Dy(III) in DMSO. The solvent composition in the first coordination sphere of Cm(III) and Ln(III) in binary mixed solvents was also studied by measuring the luminescence lifetime. Cm(III) and Ln(III) were preferentially solvated by DMSO in DMSO-H 2 O, by DMF in DMF-H 2 O, and by H 2 O in MeOH-H 2 O over the whole range of the solvent composition. The order of the preferential solvation, i.e., DMSO > DMF > H 2 O > MeOH, correlates with the relative basicity of these solvents. The Gibbs free energy of transfer of ions from water to nonaqueous solvents was further estimated from the degree of the preferential solvation. (orig.)

  11. Electrodeposition of tantalum on carbon black in non-aqueous solution and its electrocatalytic properties

    International Nuclear Information System (INIS)

    Jo, Ara; Lee, Youngmi; Lee, Chongmok

    2016-01-01

    In this work, we synthesized tantalum (Ta) nanoclusters on carbon black (Ta/CB) via simple electrodeposition in non-aqueous solvent, acetonitrile (ACN) at ambient temperature. Transmission electron microscopy (TEM) images showed that the electrodeposited Ta nanoclusters consisted of tiny Ta nanoparticles. X-ray photoelectron spectroscopy (XPS) result represented that the outermost Ta formed the native oxide on Ta/CB due to its ambient exposure to air. Electrochemical catalytic properties of prepared Ta/CB on glassy carbon electrode (Ta/CB/GC) were investigated toward reductions of oxygen and hydrogen peroxide, and oxidations of ascorbic acid and dopamine. For oxygen reduction reaction (ORR) in acid, Ta/CB/GC represented a decent electrocatalytic performance which was better or comparable to bare Pt. The operational stability in acidic condition was maintained up to 500 repetitive potential cycles presumably due to the protective native Ta oxide layer. Ta/CB/GC also showed high amperometric sensitivity (4.5 (±0.1_6) mA mM"−"1 cm"−"2, n = 5) for reduction of hydrogen peroxide in 0.1 M phosphate buffer solution (PBS, pH 7.4). In addition, Ta/CB/GC was demonstrated for the possibility of simultaneous detection of ascorbic acid and dopamine using differential pulse voltammetry (DPV). - Highlights: • We electrodeposited Ta nanoclusters (Ta/CB/GC) in acetonitrile at room temperature. • The Ta/CB/GC showed better or comparable performance to bare Pt for ORR. • The Ta/CB/GC showed high sensitivity for reduction of hydrogen peroxide at pH 7.4. • The Ta/CB/GC showed possible simultaneous detection of ascorbic acid and dopamine. • We extended the applicability of Ta electrode material for various electrocatalytic reactions.

  12. Enhanced mobility of non aqueous phase liquid (NAPL) during drying of wet sand

    Science.gov (United States)

    Govindarajan, Dhivakar; Deshpande, Abhijit P.; Raghunathan, Ravikrishna

    2018-02-01

    Enhanced upward mobility of a non aqueous phase liquid (NAPL) present in wet sand during natural drying, and in the absence of any external pressure gradients, is reported for the first time. This mobility was significantly higher than that expected from capillary rise. Experiments were performed in a glass column with a small layer of NAPL-saturated sand trapped between two layers of water-saturated sand. Drying of the wet sand was induced by flow of air across the top surface of the wet sand. The upward movement of the NAPL, in the direction of water transport, commenced when the drying effect reached the location of the NAPL and continued as long as there was significant water evaporation in the vicinity of NAPL, indicating a clear correlation between the NAPL rise and water evaporation. The magnitude and the rate of NAPL rise was measured at different water evaporation rates, different initial locations of the NAPL, different grain size of the sand and the type of NAPL (on the basis of different NAPL-glass contact angle, viscosity and density). A positive correlation was observed between average rate of NAPL rise and the water evaporation while a negative correlation was obtained between the average NAPL rise rate and the NAPL properties of contact angle, viscosity and density. There was no significant correlation of average NAPL rise rate with variation of sand grain size between 0.1 to 0.5 mm. Based on these observations and on previous studies reported in the literature, two possible mechanisms are hypothesized -a) the effect of the spreading coefficient resulting in the wetting of NAPL on the water films created and b) a moving water film due to evaporation that "drags" the NAPL upwards. The NAPL rise reported in this paper has implications in fate and transport of chemicals in NAPL contaminated porous media such as soils and exposed dredged sediment material, which are subjected to varying water saturation levels due to drying and rewetting.

  13. Synthesis and NMR characterization of SAPO-35 from non-aqueous systems using hexamethyleneimine template

    International Nuclear Information System (INIS)

    Venkatathri, N.

    2005-01-01

    SAPO-35 was synthesized using hexamethyleneimine template in non-aqueous systems. X-ray diffraction and scanning electron micrograph analysis shows the synthesized sample is pure and well crystalline. Presence of four stages (1.6%, 0.8%, 7.8% and 8.4%) of weight loss is observed by TG/DTA analysis. FT-IR analysis in the framework region shows the presence of tetrahedral T-O-T vibrations is similar to the other known aluminophosphate molecular sieves. FT-IR spectrum in the -OH region shows stretching vibrations at 3631, 3604 and 3580 cm -1 can be assigned to OH groups in bigger cages near S6R, in bigger cages near D6R and those actually confined inside the D6R, respectively. The spectra for the as-synthesized sample show a single symmetrical 27 Al MAS NMR line at δ = 36.26 indicating the presence of a single tetrahedral aluminium species. Where as 29 Si and 31 P MAS NMR shows the presence of two peaks in both at (-89.9 and -95.15 ppm) and (-34.01 and -40.45 ppm) due to the Si substitution of P present in two different locations in double 6 ring (D6R) and in single 6 ring (S6R). 27 Al 3Q-MAS NMR shows two peaks for environmentally different tetrahedral aluminium atoms. This is the first time we are showing such a fact which is not observable using ordinary MAS NMR

  14. Electrodeposition of tantalum on carbon black in non-aqueous solution and its electrocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Ara; Lee, Youngmi, E-mail: youngmilee@ewha.ac.kr; Lee, Chongmok, E-mail: cmlee@ewha.ac.kr

    2016-08-24

    In this work, we synthesized tantalum (Ta) nanoclusters on carbon black (Ta/CB) via simple electrodeposition in non-aqueous solvent, acetonitrile (ACN) at ambient temperature. Transmission electron microscopy (TEM) images showed that the electrodeposited Ta nanoclusters consisted of tiny Ta nanoparticles. X-ray photoelectron spectroscopy (XPS) result represented that the outermost Ta formed the native oxide on Ta/CB due to its ambient exposure to air. Electrochemical catalytic properties of prepared Ta/CB on glassy carbon electrode (Ta/CB/GC) were investigated toward reductions of oxygen and hydrogen peroxide, and oxidations of ascorbic acid and dopamine. For oxygen reduction reaction (ORR) in acid, Ta/CB/GC represented a decent electrocatalytic performance which was better or comparable to bare Pt. The operational stability in acidic condition was maintained up to 500 repetitive potential cycles presumably due to the protective native Ta oxide layer. Ta/CB/GC also showed high amperometric sensitivity (4.5 (±0.1{sub 6}) mA mM{sup −1} cm{sup −2}, n = 5) for reduction of hydrogen peroxide in 0.1 M phosphate buffer solution (PBS, pH 7.4). In addition, Ta/CB/GC was demonstrated for the possibility of simultaneous detection of ascorbic acid and dopamine using differential pulse voltammetry (DPV). - Highlights: • We electrodeposited Ta nanoclusters (Ta/CB/GC) in acetonitrile at room temperature. • The Ta/CB/GC showed better or comparable performance to bare Pt for ORR. • The Ta/CB/GC showed high sensitivity for reduction of hydrogen peroxide at pH 7.4. • The Ta/CB/GC showed possible simultaneous detection of ascorbic acid and dopamine. • We extended the applicability of Ta electrode material for various electrocatalytic reactions.

  15. Mass spectrometric detection of proteins in non-aqueous media : the case of prion proteins in biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Douma, M.D.; Kerr, G.M.; Brown, R.S.; Keller, B.O.; Oleschuk, R.D. [Queen' s Univ., Kingston, ON (Canada). Dept. of Chemistry

    2008-08-15

    This paper presented a filtration method for detecting protein traces in non-aqueous media. The extraction technique used a mixture of acetonitrile, non-ionic detergent and water along with filter disks with embedded C{sub 8}-modified silica particles to capture the proteins from non-aqueous samples. The extraction process was then followed by an elution of the protein from the filter disk and direct mass spectrometric detection and tryptic digestion with peptide mapping and MS/MS fragmentation of protein-specific peptides. The method was used to detect prion proteins in spiked biodiesel samples. A tryptic peptide with the sequence YGQGSPGGNR was used for unambiguous identification. Results of the study showed that the method is suitable for the large-scale testing of protein impurities in tallow-based biodiesel production processes. 33 refs., 6 figs.

  16. Partially Fluorinated Solvent as a co-solvent for the Non-aqueous Electrolyte of Li/air Battery

    Science.gov (United States)

    2010-11-11

    ether ( MFE ) and tris(2,2,2-trifluoroethyl) phosphite (TTFP), respectively, as a co-solvent for the non-aqueous electrolyte of Li–air battery. Results...fluorinated solvents on the discharge performance of Li–air bat- tery. For this purpose, we here selectmethyl nonafluorobutyl ether ( MFE ) and tris...196, (2011) pgs. 2867-2870 14. ABSTRACT In this workwestudy methyl nonafluorobutyl ether ( MFE ) and tris(2,2,2-trifluoroethyl) phosphite (TTFP

  17. 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.

  18. Rapid Synthesis of Gold Nano-Particles Using Pulse Waved Potential in a Non-Aqueous Electrolyte

    Directory of Open Access Journals (Sweden)

    Jang J.G.

    2017-06-01

    Full Text Available Rapid synthesis of gold nanoparticles (AuNPs by pulsed electrodeposition was investigated in the non-aqueous electrolyte, 1-ethyl-3-methyl-imidazoliumbis(trifluoro-methanesulfonylimide ([EMIM]TFSI with gold trichloride (AuCl3. To aid the dissolution of AuCl3, 1-ethyl-3-methyl-imidazolium chloride ([EMIM]Cl was used as a supporting electrolyte in [EMIM]TFSI. Cyclic voltammetry experiments revealed a cathodic reaction corresponding to the reduction of gold at −0.4 V vs. Pt-QRE. To confirm the electrodeposition process, potentiostatic electrodeposition of gold in the non-aqueous electrolyte was conducted at −0.4 V for 1 h at room temperature. To synthesize AuNPs, pulsed electrodeposition was conducted with controlled duty factor, pulse duration, and overpotential. The composition, particle-size distribution, and morphology of the AuNPs were confirmed by field-emission scanning electron microscopy (FE-SEM, energy-dispersive spectroscopy (EDS, and transmission electron microscopy (TEM. The electrodeposited AuNPs were uniformly distributed on the platinum electrode surface without any impurities arising from the non-aqueous electrolyte. The size distribution of AuNPs could be also controlled by the electrodeposition conditions.

  19. Semi-empirical correlation for binary interaction parameters of the Peng–Robinson equation of state with the van der Waals mixing rules for the prediction of high-pressure vapor–liquid equilibrium

    Directory of Open Access Journals (Sweden)

    Seif-Eddeen K. Fateen

    2013-03-01

    Full Text Available Peng–Robinson equation of state is widely used with the classical van der Waals mixing rules to predict vapor liquid equilibria for systems containing hydrocarbons and related compounds. This model requires good values of the binary interaction parameter kij. In this work, we developed a semi-empirical correlation for kij partly based on the Huron–Vidal mixing rules. We obtained values for the adjustable parameters of the developed formula for over 60 binary systems and over 10 categories of components. The predictions of the new equation system were slightly better than the constant-kij model in most cases, except for 10 systems whose predictions were considerably improved with the new correlation.

  20. Semi-empirical correlation for binary interaction parameters of the Peng-Robinson equation of state with the van der Waals mixing rules for the prediction of high-pressure vapor-liquid equilibrium.

    Science.gov (United States)

    Fateen, Seif-Eddeen K; Khalil, Menna M; Elnabawy, Ahmed O

    2013-03-01

    Peng-Robinson equation of state is widely used with the classical van der Waals mixing rules to predict vapor liquid equilibria for systems containing hydrocarbons and related compounds. This model requires good values of the binary interaction parameter kij . In this work, we developed a semi-empirical correlation for kij partly based on the Huron-Vidal mixing rules. We obtained values for the adjustable parameters of the developed formula for over 60 binary systems and over 10 categories of components. The predictions of the new equation system were slightly better than the constant-kij model in most cases, except for 10 systems whose predictions were considerably improved with the new correlation.

  1. Electrical resistivity for detecting subsurface non-aqueous phase liquids: A progress report

    International Nuclear Information System (INIS)

    Lee, K.H.; Shan, C.; Javandel, I.

    1995-06-01

    Soils and groundwater have been contaminated by hazardous substances at many places in the United States and many other countries. The contaminants are commonly either petroleum products or industrial solvents with very low solubility in water. These contaminants are usually called non-aqueous phase liquids (NAPLs). The cost of cleaning up the affected sites in the United States is estimated to be of the order of 100 billion dollars. In spite of the expenditure of several billion dollars during the last 15 years, to date, very few, if any major contaminated site has been restored. The presence of NAPL pools in the subsurface is believed to be the main cause for the failure of previous cleanup activities. Due to their relatively low water solubility, and depending on their volume, it takes tens or even hundreds of years to deplete the NAPL sources if they are not removed from the subsurface. The intrinsic electrical resistivity of most NAPLs is typically in the range of 10 7 to 10 12 Ω-m, which is several orders of magnitude higher than that of groundwater containing dissolved solids (usually in the range of a few Ω-m to a few thousand Ω-m). Although a dry soil is very resistive, the electrical resistivity of a wet soil is on the order of 100 Ω-m and is dependent on the extent of water saturation. For a given soil, the electrical resistivity increases with decrease of water saturation. Therefore, if part of the pore water is replaced by a NAPL, the electrical resistivity will increase. At many NAPL sites, both the vadose and phreatic zones can be partially occupied by NAPL pools. It is the great contrast in electrical resistivity between the NAPLs and groundwater that may render the method to be effective in detecting subsurface NAPLs at contaminated sites. The following experiments were conducted to investigate the change of the electrical resistivity of porous media when diesel fuel (NAPL) replaces part of the water

  2. Investigations of oxygen reduction reactions in non-aqueous electrolytes and the lithium-air battery

    Science.gov (United States)

    O'Laoire, Cormac Micheal

    Unlocking the true energy capabilities of the lithium metal negative electrode in a lithium battery has until now been limited by the low capacity intercalation and conversion reactions at the positive electrodes. This is overcome by removing these electrodes and allowing lithium to react directly with oxygen in the atmosphere forming the Li-air battery. Chapter 2 discusses the intimate role of electrolyte, in particular the role of ion conducting salts on the mechanism and kinetics of oxygen reduction in non-aqueous electrolytes designed for such applications and in determining the reversibility of the electrode reactions. Such fundamental understanding of this high energy density battery is crucial to harnessing its full energy potential. The kinetics and mechanisms of O2 reduction in solutions of hexafluorophosphate salts of the general formula X+ PF6-, where, X = tetra butyl ammonium (TBA), K, Na and Li, in acetonitrile have been studied on glassy carbon electrodes using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. Our results show that cation choice strongly influences the reduction mechanism of O2. Electrochemical data supports the view that alkali metal oxides formed via electrochemical and chemical reactions passivate the electrode surface inhibiting the kinetics and reversibility of the processes. The O2 reduction mechanisms in the presence of the different cations have been supplemented by kinetic parameters determined from detailed analyses of the CV and RDE data. The organic solvent present in the Li+-conducting electrolyte has a major role on the reversibility of each of the O2 reduction products as found from the work discussed in the next chapter. A fundamental study of the influence of solvents on the oxygen reduction reaction (ORR) in a variety of non-aqueous electrolytes was conducted in chapter 4. In this work special attention was paid to elucidate the mechanism of the oxygen electrode processes in the rechargeable Li

  3. Interacting binaries

    CERN Document Server

    Shore, S N; van den Heuvel, EPJ

    1994-01-01

    This volume contains lecture notes presented at the 22nd Advanced Course of the Swiss Society for Astrophysics and Astronomy. The contributors deal with symbiotic stars, cataclysmic variables, massive binaries and X-ray binaries, in an attempt to provide a better understanding of stellar evolution.

  4. Photoluminescent properties of Y2O3:Eu3+ phosphors prepared via urea precipitation in non-aqueous solution

    International Nuclear Information System (INIS)

    Sun, Y.; Qi, L.; Lee, M.; Lee, B.I.; Samuels, W.D.; Exarhos, G.J.

    2004-01-01

    Europium-doped yttrium oxide phosphors were obtained by firing precursors prepared by urea precipitation in ethanol and ethylenediamine. The precipitation in non-aqueous solution was carried out in an autoclave at 150 deg. C to allow the decomposition of urea. The photoluminescent intensities of the phosphors prepared in ethanol and ethylenediamine increased by about 30% compared to that of the phosphor prepared by the conventional urea homogeneous precipitation in aqueous solution. Amorphous carbonates and amorphous hydroxides/carbonates mixtures were identified as precursors from ethanol and ethylenediamine, respectively. The morphology and particle size were studied by SEM and dynamic laser scattering method

  5. Determination of heavy polycyclic aromatic hydrocarbons by non-aqueous reversed phase liquid chromatography: Application and limitation in refining streams.

    Science.gov (United States)

    Panda, Saroj K; Muller, Hendrik; Al-Qunaysi, Thunayyan A; Koseoglu, Omer R

    2018-01-19

    The heavy polycyclic aromatic hydrocarbons (HPAHs) cause detrimental effects to hydrocracker operations by deactivating the catalysts and depositing in the downstream of the reactor/ exchangers. Therefore, it is essential to continuously monitor the accumulation of HPAHs in a hydrocracker unit. To accurately measure the concentration of HPAHs, the development of a fast and reliable analytical method is inevitable. In this work, an analytical method based on non-aqueous reversed phase chromatography in combination with high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was developed. As a first step, five different types of stationary phases were evaluated for the separation of HPAHs in non-aqueous mode and the best suited phase was further used for the fractionation of HPAHs in a fractionator bottom sample obtained from a refinery hydrocracker unit. The eight major fractions or peaks obtained from the separation were further characterized by UV spectroscopy and FT-ICR MS and the compounds in the fractions were tentatively confirmed as benzoperylene, coronene, methylcoronene, naphthenocoronene, benzocoronene, dibenzoperylene, naphthocoronene and ovalene. The developed liquid chromatography method can be easily adapted in a refinery laboratory for the quantitation of HPAHs in hydrocracking products. The method was further tested to check the interference of sulfur aromatics and/or large alkylated aromatic hydrocarbons on the determination of HPAHs in hydrocracking products. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Homogeneous dispersion of gadolinium oxide nanoparticles into a non-aqueous-based polymer by two surface treatments

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Jorice, E-mail: jorice.samuel@gmail.com [AREVA T and D UK Ltd, AREVA T and D Research and Technology Centre (United Kingdom); Raccurt, Olivier [NanoChemistry and Nanosafety Laboratory (DRT/LITEN/DTNM/LCSN), CEA Grenoble, Department of NanoMaterials (France); Mancini, Cedric; Dujardin, Christophe; Amans, David; Ledoux, Gilles [Universite de Lyon, Laboratoire de Physico Chimie des Materiaux Luminescents (LPCML) (France); Poncelet, Olivier [NanoChemistry and Nanosafety Laboratory (DRT/LITEN/DTNM/LCSN), CEA Grenoble, Department of NanoMaterials (France); Tillement, Olivier [Universite de Lyon, Laboratoire de Physico Chimie des Materiaux Luminescents (LPCML) (France)

    2011-06-15

    Gadolinium oxide nanoparticles are more and more used. They can notably provide interesting fluorescence properties. Herein they are incorporated into a non-aqueous-based polymer, the poly(methyl methacrylate). Their dispersion within the polymer matrix is the key to improve the composite properties. As-received gadolinium oxide nanopowders cannot be homogeneously dispersed in such a polymer matrix. Two surface treatments are, therefore, detailed and compared to achieve a good stability of the nanoparticles in a non-aqueous solvent such as the 2-butanone. Then, once the liquid suspensions have been stabilized, they are used to prepare nanocomposites with homogeneous particles dispersion. The two approaches proposed are an hybrid approach based on the growth of a silica shell around the gadolinium oxide nanoparticles, and followed by a suitable silane functionalization; and a non-hybrid approach based on the use of surfactants. The surface treatments and formulations involved in both methods are detailed, adjusted and compared. Thanks to optical methods and in particular to the use of a 'home made' confocal microscope, the dispersion homogeneity within the polymer can be assessed. Both methods provide promising and conclusive results.

  7. Cathodic behaviours of a CrO sub 3 -graphite intercalation compound in non-aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, M.; Miura, T.; Kishi, T. (Keio University, Tokyo (Japan). Faculty of Science)

    1991-08-05

    CrO{sub 3}-graphite intercalation compound (GIC) specimen was prepared by solvent method using acetic acid as a solvent and potassium permanganate as a catalyst, and its cathodic behavior in a lithium cell was studied in non-aqueous solutions (1 mol/dm{sup 3} LiClO{sub 4} in propylene carbonate (PC) or dimethylsulfoxide (DMSO)). Changes in electronic and layered lattice structures induced by cathodic reduction were measured by electron spin resonance method and X-ray diffraction one, respectively. As a result, electrochemical insertion of Li into CrO{sub 3}-GIC proceeded only in DMSO solution where reduction of Cr components was followed by that of graphite units. The amount of discharge electricity for CrO{sub 3}-GIC in DMSO solution was three times as large as that for graphite. Although the effect of non-aqueous solutions on the lithiation reaction was not yet clear fundamentally, it was expected that another electrolyte solutions are probably found out based on this experiments from which Li is inserted into CrO{sub 3}-GIC at higher discharge potentials. 22 refs., 9 figs., 1 tab.

  8. Electrochemical reactions of uranyl(VI) complexes in aqueous solution, non-aqueous solvents, and ionic liquids

    International Nuclear Information System (INIS)

    Ikeda, Yasuhisa

    2006-01-01

    Author's recent experimental results on the chemistry of U(V) in aqueous solution, non-aqueous solvents, and ionic solvents by cyclic voltametry are described. The U(V) was produced by electrochemical reduction of uranyl U(VI) ions or complexes such as carbonates, DMF(N, N-dimethylformamide), DMSO(dimethylsulfoxide), acetylacetonato, and other organic polydental ligands. The produced U(V) complexes were studied by spectrophotometry using optical-transmission thin-layer electrode. The U(V) complexes in non-aqueous solvents were found to be rather stable, they undergo ligand-dissociation reaction but not disproportionation reaction. The structure and electronic spectra as well as IR spectra of the complexes were studied. The present method was further developed to study the behavior of U(V) complexes in ionic liquids as molten salts, e.g., alkaline metals chlorides. Thus, the present research contributes to understanding the chemistry of 5fl system. Application to such nuclear technology as spent fuel reprocessing is discussed. (S. Ohno)

  9. The IUPAC aqueous and non-aqueous experimental pKa data repositories of organic acids and bases.

    Science.gov (United States)

    Slater, Anthony Michael

    2014-10-01

    Accurate and well-curated experimental pKa data of organic acids and bases in both aqueous and non-aqueous media are invaluable in many areas of chemical research, including pharmaceutical, agrochemical, specialty chemical and property prediction research. In pharmaceutical research, pKa data are relevant in ligand design, protein binding, absorption, distribution, metabolism, elimination as well as solubility and dissolution rate. The pKa data compilations of the International Union of Pure and Applied Chemistry, originally in book form, have been carefully converted into computer-readable form, with value being added in the process, in the form of ionisation assignments and tautomer enumeration. These compilations offer a broad range of chemistry in both aqueous and non-aqueous media and the experimental conditions and original reference for all pKa determinations are supplied. The statistics for these compilations are presented and the utility of the computer-readable form of these compilations is examined in comparison to other pKa compilations. Finally, information is provided about how to access these databases.

  10. Properties of Eco-friendly Acrylic Resin/Clay Nanocomposites Prepared by Non-aqueous Dispersion (NAD) Polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeongho; Lee, Minho; Jeon, Hyeon Yeol; Min, Byong Hun; Kim, Jeong Ho [Univ. of Suwon, Hwaseong (Korea, Republic of); Lee, Young Chul [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)

    2016-02-15

    Eco-friendly acrylic resin/clay nanocomposites containing pristine montmorillonite (PM) or modified clays (30B and 25A) were prepared from acrylic and styrenic monomers using non-aqueous dispersion (NAD) polymerization. Effect of nanoclays on physical properties of polymerization product and resulting nanocomposites was investigated. In view of NAD particle stability, addition of nanoclay at the beginning of polymerization is proved to be good. Results of gel fraction, acid value and viscosity of the NAD product showed that nanocomposites containing clay 25A showed better physical properties than the ones with other clays. GPC results exhibit the increase in molecular weight and decrease in polydispersity index for the 25A nanocomposite. Increase in layer distance confirmed from XRD analysis showed good dispersion of 25A in the nanocomposite. Thermal and dynamic mechanical analysis showed that highest glass transition temperature and storage modulus for 25A nanocomposites. These results indicate that 25A nanoclay gives the best properties in the process of non-aqueous dispersion polymerization of acrylic resin/nanoclay nanocomposites.

  11. Templated growth of cadmium zinc telluride (CZT) nanowires using pulsed-potentials in hot non-aqueous solution

    International Nuclear Information System (INIS)

    Gandhi, T.; Raja, K.S.; Misra, M.

    2006-01-01

    A single step non-aqueous electrodeposition of cadmium zinc telluride (CZT) nanowires on nanoporous TiO 2 substrate was investigated under pulsed-potential conditions. Propylene carbonate was used as the non-aqueous medium. Cyclic voltammogram studies were carried out to understand the growth mechanism of CZT. EDAX and XRD measurements indicated formation of a compound semiconductor with a stoichiometry of Cd 1-x Zn x Te, where x varied between 0.04 and 0.2. Variation of the pulsed-cathodic potentials could modulate the composition of the CZT. More negative cathodic potentials resulted in increased Zn content. The nanowires showed an electronic band gap of about 1.6 eV. Mott-Schottky analyses indicated p-type semiconductor properties of both as-deposited and annealed CZT materials. Increase in Zn content increased the charge carrier density. Annealing of the deposits resulted in lower charge carrier densities, in the order of 10 15 cm -3

  12. Properties of Eco-friendly Acrylic Resin/Clay Nanocomposites Prepared by Non-aqueous Dispersion (NAD) Polymerization

    International Nuclear Information System (INIS)

    Kim, Yeongho; Lee, Minho; Jeon, Hyeon Yeol; Min, Byong Hun; Kim, Jeong Ho; Lee, Young Chul

    2016-01-01

    Eco-friendly acrylic resin/clay nanocomposites containing pristine montmorillonite (PM) or modified clays (30B and 25A) were prepared from acrylic and styrenic monomers using non-aqueous dispersion (NAD) polymerization. Effect of nanoclays on physical properties of polymerization product and resulting nanocomposites was investigated. In view of NAD particle stability, addition of nanoclay at the beginning of polymerization is proved to be good. Results of gel fraction, acid value and viscosity of the NAD product showed that nanocomposites containing clay 25A showed better physical properties than the ones with other clays. GPC results exhibit the increase in molecular weight and decrease in polydispersity index for the 25A nanocomposite. Increase in layer distance confirmed from XRD analysis showed good dispersion of 25A in the nanocomposite. Thermal and dynamic mechanical analysis showed that highest glass transition temperature and storage modulus for 25A nanocomposites. These results indicate that 25A nanoclay gives the best properties in the process of non-aqueous dispersion polymerization of acrylic resin/nanoclay nanocomposites

  13. Polyoxovanadate-alkoxide clusters as multi-electron charge carriers for symmetric non-aqueous redox flow batteries.

    Science.gov (United States)

    VanGelder, L E; Kosswattaarachchi, A M; Forrestel, P L; Cook, T R; Matson, E M

    2018-02-14

    Non-aqueous redox flow batteries have emerged as promising systems for large-capacity, reversible energy storage, capable of meeting the variable demands of the electrical grid. Here, we investigate the potential for a series of Lindqvist polyoxovanadate-alkoxide (POV-alkoxide) clusters, [V 6 O 7 (OR) 12 ] (R = CH 3 , C 2 H 5 ), to serve as the electroactive species for a symmetric, non-aqueous redox flow battery. We demonstrate that the physical and electrochemical properties of these POV-alkoxides make them suitable for applications in redox flow batteries, as well as the ability for ligand modification at the bridging alkoxide moieties to yield significant improvements in cluster stability during charge-discharge cycling. Indeed, the metal-oxide core remains intact upon deep charge-discharge cycling, enabling extremely high coulombic efficiencies (∼97%) with minimal overpotential losses (∼0.3 V). Furthermore, the bulky POV-alkoxide demonstrates significant resistance to deleterious crossover, which will lead to improved lifetime and efficiency in a redox flow battery.

  14. Macromolecular Design Strategies for Preventing Active-Material Crossover in Non-Aqueous All-Organic Redox-Flow Batteries.

    Science.gov (United States)

    Doris, Sean E; Ward, Ashleigh L; Baskin, Artem; Frischmann, Peter D; Gavvalapalli, Nagarjuna; Chénard, Etienne; Sevov, Christo S; Prendergast, David; Moore, Jeffrey S; Helms, Brett A

    2017-02-01

    Intermittent energy sources, including solar and wind, require scalable, low-cost, multi-hour energy storage solutions in order to be effectively incorporated into the grid. All-Organic non-aqueous redox-flow batteries offer a solution, but suffer from rapid capacity fade and low Coulombic efficiency due to the high permeability of redox-active species across the battery's membrane. Here we show that active-species crossover is arrested by scaling the membrane's pore size to molecular dimensions and in turn increasing the size of the active material above the membrane's pore-size exclusion limit. When oligomeric redox-active organics (RAOs) were paired with microporous polymer membranes, the rate of active-material crossover was reduced more than 9000-fold compared to traditional separators at minimal cost to ionic conductivity. This corresponds to an absolute rate of RAO crossover of less than 3 μmol cm -2  day -1 (for a 1.0 m concentration gradient), which exceeds performance targets recently set forth by the battery industry. This strategy was generalizable to both high and low-potential RAOs in a variety of non-aqueous electrolytes, highlighting the versatility of macromolecular design in implementing next-generation redox-flow batteries. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. High Performance Redox Flow Batteries: An Analysis of the Upper Performance Limits of Flow Batteries Using Non-aqueous Solvents

    International Nuclear Information System (INIS)

    Sun, C.-N.; Mench, M.M.; Zawodzinski, T.A.

    2017-01-01

    Redox Flow Batteries (RFBs) are a promising technology for grid-scale electrochemical energy storage. In this work, we use a recently achieved high-performance flow battery performance curve as a basis to assess the maximum achievable performance of a RFB employing non-aqueous solutions as active materials. First we show high performance in a vanadium redox flow battery (VRFB), specifically a limiting situation in which the cell losses are ohmic in nature and derive from electrolyte conductance. Based on that case, we analyze the analogous limiting behavior of non-aqueous (NA) systems using a series of calculations assuming similar ohmic losses, scaled by the relative electrolyte resistances, with a higher voltage redox couple assumed for the NA battery. The results indicate that the NA battery performance is limited by the low electrolyte conductivity to a fraction of the performance of the VRFB. Given the narrow window in which the NARFB offers advantages, even for the most generous limiting assumptions related to performance while ignoring the numerous other disadvantageous aspects of these systems, we conclude that this technology is unlikely under present circumstances to provide practical large-scale energy storage solutions.

  16. Thermodynamic and analytical studies of drugs binary systems of paracetamol mixed with pseudoephedrine.HCl, dextropropoxyphene.HCl and tramadol.HCl

    International Nuclear Information System (INIS)

    Boumrah, Yacine; Bouzahia, Imane; Bouanani, Sabrina; Khimeche, Kamel; Dahmani, Abdallah

    2016-01-01

    Highlights: • Solid–liquid equilibria of binary drug mixtures were investigated by DSC. • The study revealed a simple eutectic behavior of the investigated drug binary systems. • DSC results have been exploited for quantification purpose. • DSC quantification results were in good agreement with those obtained by HPTLC. - Abstract: In this paper, we report a DSC investigation of solid–liquid equilibria in three binary mixtures of paracetamol, namely with pseudoephedrine, dextropropoxyphene and tramadol, resulting in a temperature-composition phase diagrams with eutectic equilibrium. Eutectic mole fractions, temperatures and enthalpies were determined and reported for each system. The study reports also a direct exploitation of the DSC results for the quantification purpose, which were in good agreement with those obtained by a standard analytical method namely high performance thin layer chromatography (HPTLC), used in this work for comparison purpose.

  17. Thermodynamic and analytical studies of drugs binary systems of paracetamol mixed with pseudoephedrine.HCl, dextropropoxyphene.HCl and tramadol.HCl

    Energy Technology Data Exchange (ETDEWEB)

    Boumrah, Yacine [Laboratoire de thermodynamique et modélisation moléculaire, Faculté de chimie, USTHB, BP 32 El-Alia, 16111, Bab-Ezzouar, Alger (Algeria); Institut National de Criminalistique et de Criminologie (INCC-GN), Bouchaoui, Alger (Algeria); Bouzahia, Imane; Bouanani, Sabrina [Institut National de Criminalistique et de Criminologie (INCC-GN), Bouchaoui, Alger (Algeria); Khimeche, Kamel [Ecole Militaire Polytechnique EMP, BP 17 Bordj-El-Bahri, Alger (Algeria); Dahmani, Abdallah, E-mail: adahmani@yahoo.fr [Laboratoire de thermodynamique et modélisation moléculaire, Faculté de chimie, USTHB, BP 32 El-Alia, 16111, Bab-Ezzouar, Alger (Algeria)

    2016-06-20

    Highlights: • Solid–liquid equilibria of binary drug mixtures were investigated by DSC. • The study revealed a simple eutectic behavior of the investigated drug binary systems. • DSC results have been exploited for quantification purpose. • DSC quantification results were in good agreement with those obtained by HPTLC. - Abstract: In this paper, we report a DSC investigation of solid–liquid equilibria in three binary mixtures of paracetamol, namely with pseudoephedrine, dextropropoxyphene and tramadol, resulting in a temperature-composition phase diagrams with eutectic equilibrium. Eutectic mole fractions, temperatures and enthalpies were determined and reported for each system. The study reports also a direct exploitation of the DSC results for the quantification purpose, which were in good agreement with those obtained by a standard analytical method namely high performance thin layer chromatography (HPTLC), used in this work for comparison purpose.

  18. Trojan Binaries

    Science.gov (United States)

    Noll, K. S.

    2017-12-01

    The Jupiter Trojans, in the context of giant planet migration models, can be thought of as an extension of the small body populations found beyond Neptune in the Kuiper Belt. Binaries are a distinctive feature of small body populations in the Kuiper Belt with an especially high fraction apparent among the brightest Cold Classicals. The binary fraction, relative sizes, and separations in the dynamically excited populations (Scattered, Resonant) reflects processes that may have eroded a more abundant initial population. This trend continues in the Centaurs and Trojans where few binaries have been found. We review new evidence including a third resolved Trojan binary and lightcurve studies to understand how the Trojans are related to the small body populations that originated in the outer protoplanetary disk.

  19. Acoustic, volumetric and osmotic properties of binary mixtures containing the ionic liquid 1-butyl-3-methylimidazolium dicyanamide mixed with primary and secondary alcohols

    International Nuclear Information System (INIS)

    Calvar, Noelia; González, Emilio J.; Domínguez, Ángeles; Macedo, Eugénia A.

    2012-01-01

    Highlights: ► Physical and osmotic properties of binary mixtures {alcohol + [BMim][dca]} were measured. ► From experimental data, apparent molar properties and osmotic coefficients were calculated. ► The apparent properties were fitted using a Redlich–Meyer type equation. ► The osmotic coefficients were correlated using the Extended Pitzer and the MNRTL models. - Abstract: In this paper, densities and speeds of sound for five binary systems {alcohol + 1-butyl-3-methylimidazolium dicyanamide} were measured from T = (293.15 to 323.15) K and atmospheric pressure. From these experimental data, apparent molar volume and apparent molar isentropic compression have been calculated and fitted to a Redlich–Meyer type equation. This fit was also used to calculate the apparent molar volume and apparent molar isentropic compression at infinite dilution for the studied binary mixtures. Moreover, the osmotic and activity coefficients and vapor pressures of these binary mixtures were also determined at T = 323.15 K using the vapor pressure osmometry technique. The experimental osmotic coefficients were correlated using the Extended Pitzer model of Archer. The mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated from the parameters obtained in the correlation.

  20. Products of prime powers in binary recurrence sequences : part II. The elliptic case, with an application to a mixed quadratic-exponential equation

    NARCIS (Netherlands)

    Weger, de B.M.M.

    1986-01-01

    In Part I the diophantine equation [formula] was studied, where [formula] is a linear binary recurrence sequence with positive discriminant. In this second part we extend this to negative discriminants. We use the p-adic and complex Gelfond-Baker theory to find explicit upper bounds for the

  1. Recent developments in thermodynamics and thermophysics of non-aqueous mixtures containing ionic liquids. A review

    International Nuclear Information System (INIS)

    Heintz, Andreas

    2005-01-01

    Mixtures of ionic liquids with organic solvents exhibit a most interesting research area in thermodynamics. The increasing utilization of ionic liquids in chemical processes and separation processes requires reliable and systematic data of thermodynamic and thermophysical properties such as activity coefficients, VLE and LLE data, heats of mixing as well as gas solubility data, densities and transport properties like viscosity, electric conductivity and mutual diffusion coefficients. This review presents an survey of the most recent data material including current developments and aspects of research activities needed in the future

  2. Interaction of amines with native aluminium oxide layers in non-aqueous environment: Application to the understanding of the formation of epoxy-amine/metal interphases

    International Nuclear Information System (INIS)

    Mercier, D.; Rouchaud, J.-C.; Barthes-Labrousse, M.-G.

    2008-01-01

    Interaction of propylamine (PA), 1,2-diaminoethane (DAE) or 3-aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine, IPDA) with native aluminium oxide layers in non-aqueous environment has been studied using time-resolved inductively coupled plasma optical emission spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS). The formation of several surface complexes has been evidenced. Monodentate and bidentate metal-bond surface complexes (MBSC) result from interactions between the amine terminations of the molecule and aluminium cations by donation of the N lone electron pair to the metal ion (Lewis-like mechanism leading to O-Al...N bonds). Monodentate and bidentate hydrogen-bond surface complexes (HBSC) are due to interaction of the amino group with surface hydroxyl groups by protonation of the amine termination (Bronsted-like mechanism leading to the formation of Al-OH...N bonds) or interaction with carbonaceous contamination (C x O y H z ...N bonds). Diamines can also form mixed complexes with one amino group forming an O-Al...N bond and the other group forming an Al-OH...N or C x O y H z ...N bond. Al-OH...N and C x O y H z ...N bonds are less stable under vacuum than O-Al...N bonds, leading to partial desorption of the DAE molecules in vacuum and modification of the interaction modes. Only DAE and IPDA can lead to partial dissolution of the aluminium native (hydr)oxide films. A detailed mechanism of dissolution has been proposed based on the formation of mononuclear bidentate (chelate) MBSC by ligand exchange between the terminal η 1 -OH and bridged μ 2 -OH surface sites and the amino terminations of the molecule. The detachment of this complex from the surface is likely to be the precursor step to the formation of the interphase in epoxy-amine/metal systems

  3. Effects of non-aqueous fluids-associated drill cuttings discharge on shelf break macrobenthic communities in the Campos Basin, Brazil.

    Science.gov (United States)

    Santos, Maria Fernanda L; Silva, Janete; Fachel, Jandyra M G; Pulgati, Fernando H

    2010-08-01

    This paper assesses the effects of non-aqueous fluids (NAF)-associated drill cuttings discharge on shelf break macrobenthic communities in the Campos Basin, off the southeast Brazilian coast, Rio de Janeiro State. Samples were taken with a 0.25-m2 box corer from surrounding two oil and gas wells on three monitoring cruises: before drilling, three months after drilling, and 22 months after drilling. Statistical methodologies used Bayesian geostatistical and analysis of variance models to evaluate the effects of the NAF-associated drill cuttings discharge and to define the impact area. The results indicated that marked variations were not observed in the number of families between cruises, though there were changes in the fauna composition. The changes seen in biological descriptors in both control and background situation areas were not considered significant, showing a temporal homogeneity in means. The impact area presented changes in biological descriptors of communities and trophic structure during the three cruises and such changes were correlated to chemical and physical variables related to the drilling activities, as a result of the mix of drill cuttings and sediment and the anoxic conditions established in the substrate. In that area, three months after drilling, a decrease in diversity and an increase in density, motile deposit-feeders and Pol/Crp ratio, and dominance of opportunistic organisms, such as the capitellid Capitella sp., were observed and, 22 months after drilling, an increase of diversity, reduction of dominance of capitellid polychaete, changes in the fauna composition, and a dominance of opportunistic burrowing and tube-building organisms were observed, indicating an ecological succession process.

  4. Structure and Optical Properties of Titania-PDMS Hybrid Nanocomposites Prepared by In Situ Non-Aqueous Synthesis

    Directory of Open Access Journals (Sweden)

    Antoine R. M. Dalod

    2017-12-01

    Full Text Available Organic-inorganic hybrid materials are attractive due to the combination of properties from the two distinct types of materials. In this work, transparent titania-polydimethylsiloxane hybrid materials with up to 15.5 vol. % TiO2 content were prepared by an in situ non-aqueous method using titanium (IV isopropoxide and hydroxy-terminated polydimethylsiloxane as precursors. Spectroscopy (Fourier transform infrared, Raman, Ultraviolet-visible, ellipsometry and small-angle X-ray scattering analysis allowed to describe in detail the structure and the optical properties of the nanocomposites. Titanium alkoxide was successfully used as a cross-linker and titania-like nanodomains with an average size of approximately 4 nm were shown to form during the process. The resulting hybrid nanocomposites exhibit high transparency and tunable refractive index from 1.42 up to 1.56, depending on the titania content.

  5. Kinetics of the decomposition and the estimation of the stability of 10% aqueous and non-aqueous hydrogen peroxide solutions

    Directory of Open Access Journals (Sweden)

    Zun Maria

    2014-12-01

    Full Text Available In this study, the stability of 10% hydrogen peroxide aqueous and non-aqueous solutions with the addition of 6% (w/w of urea was evaluated. The solutions were stored at 20°C, 30°C and 40°C, and the decomposition of hydrogen peroxide proceeded according to first-order kinetics. With the addition of the urea in the solutions, the decomposition rate constant increased and the activation energy decreased. The temperature of storage also affected the decomposition of substance, however, 10% hydrogen peroxide solutions prepared in PEG-300, and stabilized with the addition of 6% (w/w of urea had the best constancy.

  6. Crosslinked anion exchange membranes prepared from poly(phenylene oxide) (PPO) for non-aqueous redox flow batteries

    Science.gov (United States)

    Li, Yun; Sniekers, Jeroen; Malaquias, João C.; Van Goethem, Cedric; Binnemans, Koen; Fransaer, Jan; Vankelecom, Ivo F. J.

    2018-02-01

    A stable and eco-friendly anion-exchange membrane (AEM) was prepared and applied in a non-aqueous all-copper redox flow battery (RFB). The AEM was prepared via a simple procedure, leading to a cross-linked structure containing quaternary ammonium groups without involvement of harmful trimethylamine. A network was thus constructed which ensured both ion transport and solvent resistance. The ion exchange capacity (IEC) of the membrane was tuned from 0.49 to 1.03 meq g-1 by varying the content of the 4, 4‧-bipyridine crosslinking agent. The membrane showed a good anion conductivity and retention of copper ions. As a proof of principle, a RFB single cell with this crosslinked membrane yielded a coulombic efficiency of 89%, a voltage efficiency of 61% and an energy efficiency of 54% at 7.5 mA cm-2.

  7. Synthesis of iron oxide nanoparticles under oxidizing environment and their stabilization in aqueous and non-aqueous media

    International Nuclear Information System (INIS)

    Maity, D.; Agrawal, D.C.

    2007-01-01

    Synthesis of magnetite (Fe 3 O 4 ) nanoparticles under oxidizing environment by precipitation from aqueous media is not straightforward because Fe 2+ gets oxidized to Fe 3+ and thus the ratio of Fe 3+ :Fe 2+ =2:1 is not maintained during the precipitation. A molar ratio of Fe 3+ :Fe 2+ smaller than 2:1 has been used by many to compensate for the oxidation of Fe 2+ during the preparation. In this work, we have prepared iron oxide nanoparticles in air environment by the precipitation technique using initial molar ratios Fe 3+ :Fe 2+ ≤2:1. The phases of the resulting powders have been determined by several techniques. It is found that the particles consist mainly of maghemite with little or no magnetite phase. The particles have been suspended in non-aqueous and aqueous media by coating the particles with a single layer and a bilayer of oleic acid, respectively. The particle sizes, morphology and the magnetic properties of the particles and the ferrofulids prepared from these particles are reported. The average particle sizes obtained from the TEM micrographs are 14, 10 and 9 nm for the water, kerosene and dodecane-based ferrofluids, respectively, indicating a better dispersion in the non-aqueous media. The specific saturation magnetization (σ s ) value of the oleic-acid-coated particles (∼53 emu/g) is found to be lower than that for the uncoated particles (∼63 emu/g). Magnetization σ s of the dodecane-based ferrofluid is found to be 10.1 emu/g for a volume fraction of particles φ=0.019. Zero coercivity and zero remanance on the magnetization curves indicate that the particles are superparamagnetic (SPM) in nature

  8. Acoustical, volumetric and osmotic properties of binary mixtures containing the ionic liquid 1-butyl-3-metylimidazolium dicyanamide mixed with primary and secondary alcohols

    OpenAIRE

    Noélia Calvar; Emilio J. González; Ángeles Domínguez; Eugénia A. Macedo

    2012-01-01

    In this paper, densities and speeds of sound for five binary systems {alcohol + 1-butyl-3-methylimidazolium dicyanamide} were measured from T = (293.15 to 323.15) K and atmospheric pressure. From these experimental data, apparent molar volume and apparent molar isentropic compression have been calculated and fitted to a Redlich-Meyer type equation. This fit was also used to calculate the apparent molar volume and apparent molar isentropic compression at infinite dilution for the studied binar...

  9. Acoustic, volumetric and osmotic properties of binary mixtures containing the ionic liquid 1-butyl-3-methylimidazolium dicyanamide mixed with primary and secondary alcohols

    OpenAIRE

    Noélia Calvar; Emilio J. González; Dominguez, A; Maria Eugénia Macedo

    2012-01-01

    In this paper, densities and speeds of sound for five binary systems {alcohol + 1-butyl-3-methylimidazolium dicyanamide} were measured from T = (293.15 to 323.15) K and atmospheric pressure. From these experimental data, apparent molar volume and apparent molar isentropic compression have been calculated and fitted to a Redlich-Meyer type equation. This fit was also used to calculate the apparent molar volume and apparent molar isentropic compression at infinite dilution for the studied binar...

  10. On the role of structure-dynamic relationship in determining the excess entropy of mixing and chemical ordering in binary square-well liquid alloys

    Science.gov (United States)

    Lalneihpuii, R.; Shrivastava, Ruchi; Mishra, Raj Kumar

    2018-05-01

    Using statistical mechanical model with square-well (SW) interatomic potential within the frame work of mean spherical approximation, we determine the composition dependent microscopic correlation functions, interdiffusion coefficients, surface tension and chemical ordering in Ag-Cu melts. Further Dzugutov universal scaling law of normalized diffusion is verified with SW potential in binary mixtures. We find that the excess entropy scaling law is valid for SW binary melts. The partial and total structure factors in the attractive and repulsive regions of the interacting potential are evaluated and then Fourier transformed to get partial and total radial distribution functions. A good agreement between theoretical and experimental values for total structure factor and the reduced radial distribution function are observed, which consolidates our model calculations. The well-known Bhatia-Thornton correlation functions are also computed for Ag-Cu melts. The concentration-concentration correlations in the long wavelength limit in liquid Ag-Cu alloys have been analytically derived through the long wavelength limit of partial correlation functions and apply it to demonstrate the chemical ordering and interdiffusion coefficients in binary liquid alloys. We also investigate the concentration dependent viscosity coefficients and surface tension using the computed diffusion data in these alloys. Our computed results for structure, transport and surface properties of liquid Ag-Cu alloys obtained with square-well interatomic interaction are fully consistent with their corresponding experimental values.

  11. Binary effectivity rules

    DEFF Research Database (Denmark)

    Keiding, Hans; Peleg, Bezalel

    2006-01-01

    is binary if it is rationalized by an acyclic binary relation. The foregoing result motivates our definition of a binary effectivity rule as the effectivity rule of some binary SCR. A binary SCR is regular if it satisfies unanimity, monotonicity, and independence of infeasible alternatives. A binary...

  12. Effects of concentration, temperature and solvent composition on density and apparent molar volume of the binary mixtures of cationic-anionic surfactants in methanol-water mixed solvent media.

    Science.gov (United States)

    Bhattarai, Ajaya; Chatterjee, Sujeet Kumar; Niraula, Tulasi Prasad

    2013-01-01

    The accurate measurements on density of the binary mixtures of cetyltrimethylammonium bromide and sodium dodecyl sulphate in pure water and in methanol(1) + water (2) mixed solvent media containing (0.10, 0.20, and 0.30) volume fractions of methanol at 308.15, 318.15, and 323.15 K are reported. The concentrations are varied from (0.03 to 0.12) mol.l(-1) of sodium dodecyl sulphate in presence of ~ 5.0×10(-4) mol.l(-1) cetyltrimethylammonium bromide. The results showed almost increase in the densities with increasing surfactant mixture concentration, also the densities are found to decrease with increasing temperature over the entire concentration range, investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The concentration dependence of the apparent molar volumes appear to be negligible over the entire concentration range, investigated in a given mixed solvent medium and the apparent molar volumes increase with increasing temperature and are found to decrease with increasing methanol content in the solvent composition.

  13. Analysis of yohimbine alkaloid from Pausinystalia yohimbe by non-aqueous capillary electrophoresis and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Chen, Qinhua; Li, Peng; Zhang, Zhuo; Li, Kaijun; Liu, Jia; Li, Qiang

    2008-07-01

    In the present work, the qualitative and quantitative analysis of Pausinystalia yohimbe-type alkaloids in the barks of Rubiaceae species is presented using different analytical approaches. Extracts of P. yohimbe were first examined by GC-MS and the major alkaloids were identified. The quantitation of yohimbine was then accomplished by non-aqueous CE (NACE) with diode array detection. This approach was selected in order to use a running buffer fully compatible with samples in organic solvent. In particular, a mixture of methanol containing ammonium acetate (20 mM) and glacial acetic acid was used as a BGE. The same analytical sample was subjected to GC-MS and NACE analysis; the different selectivity displayed by these techniques allowed different separation profiles that can be useful in phytochemical characterization of the extracts. The linear calibration ranges were all 10-1000 microg/mL for yohimbine by GC-MS and NACE analysis. The recovery of yohimbine was 91.2-94.0% with RSD 1.4-4.3%. The LOD for yohimbine were 0.6 microg/mL by GC-MS and 1.0 microg/mL by NACE, respectively. The GC-MS and NACE methods were successfully validated and applied to the quantitation of yohimbine.

  14. Multiphase flow and transport caused by spontaneous gas phase growth in the presence of dense non-aqueous phase liquid.

    Science.gov (United States)

    Roy, James W; Smith, James E

    2007-01-30

    Disconnected bubbles or ganglia of trapped gas may occur below the top of the capillary fringe through a number of mechanisms. In the presence of dense non-aqueous phase liquid (DNAPL), the disconnected gas phase experiences mass transfer of dissolved gases, including volatile components from the DNAPL. The properties of the gas phase interface can also change. This work shows for the first time that when seed gas bubbles exist spontaneous gas phase growth can be expected to occur and can significantly affect water-gas-DNAPL distributions, fluid flow, and mass transfer. Source zone behaviour was observed in three different experiments performed in a 2-dimensional flow cell. In each case, a DNAPL pool was created in a zone of larger glass beads over smaller glass beads, which served as a capillary barrier. In one experiment effluent water samples were analyzed to determine the vertical concentration profile of the plume above the pool. The experiments effectively demonstrated a) a cycle of spontaneous gas phase expansion and vertical advective mobilization of gas bubbles and ganglia above the DNAPL source zone, b) DNAPL redistribution caused by gas phase growth and mobilization, and c) that these processes can significantly affect mass transport from a NAPL source zone.

  15. Carbon coated nano-LiTi2(PO4)3 electrodes for non-aqueous hybrid supercapacitors.

    Science.gov (United States)

    Aravindan, V; Chuiling, W; Reddy, M V; Rao, G V Subba; Chowdari, B V R; Madhavi, S

    2012-04-28

    The Pechini type polymerizable complex decomposition method is employed to prepare LiTi(2)(PO(4))(3) at 1000 °C in air. High energy ball milling followed by carbon coating by the glucose-method yielded C-coated nano-LiTi(2)(PO(4))(3) (LTP) with a crystallite size of 80(±5) nm. The phase is characterized by X-ray diffraction, Rietveld refinement, thermogravimetry, SEM, HR-TEM and Raman spectra. Lithium cycling properties of LTP show that 1.75 moles of Li (~121 mA h g(-1) at 15 mA g(-1) current) per formula unit can be reversibly cycled between 2 and 3.4 V vs. Li with 83% capacity retention after 70 cycles. Cyclic voltammograms (CV) reveal the two-phase reaction mechanism during Li insertion/extraction. A hybrid electrochemical supercapacitor (HEC) with LTP as negative electrode and activated carbon (AC) as positive electrode in non-aqueous electrolyte is studied by CV at various scan rates and by galvanostatic cycling at various current rates up to 1000 cycles in the range 0-3 V. Results show that the HEC delivers a maximum energy density of 14 W h kg(-1) and a power density of 180 W kg(-1). This journal is © the Owner Societies 2012

  16. Non-aqueous hybrid supercapacitors fabricated with mesoporous TiO2 microspheres and activated carbon electrodes with superior performance

    Science.gov (United States)

    Cai, Yong; Zhao, Bote; Wang, Jie; Shao, Zongping

    2014-05-01

    Mesoporous TiO2 microspheres, synthesized by a facile template-free solvothermal method and subsequent heat treatment, are exploited as the electrode for hybrid supercapacitors. The effects of the calcination temperature on the phase composition, particulate microstructure and morphology are characterized by XRD, Raman, FE-SEM and N2 adsorption/desorption measurements. Hybrid supercapacitors utilizing the as-prepared TiO2 mesoporous microspheres as the negative electrode and activated carbon (AC) as the positive electrode in a non-aqueous electrolyte are fabricated. The electrochemical performance of these hybrid supercapacitors is studied by galvanostatic charge-discharge and cyclic voltammetry (CV). The hybrid supercapacitor built from TiO2 microspheres calcined at 400 °C shows the best performance, delivering an energy density of 79.3 Wh kg-1 at a power density of 178.1 W kg-1. Even at a power density of 9.45 kW kg-1, an energy density of 31.5 Wh kg-1 is reached. These values are much higher than the AC-AC symmetric supercapacitor. In addition, the hybrid supercapacitor exhibits excellent cycling performance, retaining 98% of the initial energy density after 1000 cycles. Such outstanding electrochemical performance of the hybrid supercapacitor is attributed to the matched reaction kinetics between the two electrodes with different energy storage mechanisms.

  17. Electrochemical characterization of single-walled carbon nanotubes for electrochemical double layer capacitors using non-aqueous electrolyte

    International Nuclear Information System (INIS)

    Ruch, P.W.; Koetz, R.; Wokaun, A.

    2009-01-01

    Single-walled carbon nanotubes (SWCNTs) were investigated by cyclic voltammetry and electrochemical impedance spectroscopy in a non-aqueous electrolyte, 1 M Et 4 NBF 4 in acetonitrile, suitable for supercapacitors. Further, in situ dilatometry and in situ conductance measurements were performed on single electrodes and the results compared to an activated carbon, YP17. Both materials show capacitive behavior characteristic of high surface area electrodes for supercapacitors, with the maximum full cell gravimetric capacitance being 34 F/g for YP17 and 20 F/g for SWCNTs at 2.5 V with respect to the total active electrode mass. The electronic resistance of SWCNTs and activated carbon decreases significantly during charging, showing similarities of the two materials during electrochemical doping. The SWCNT electrode expands irreversibly during the first electrochemical potential sweep as verified by in situ dilatometry, indicative of at least partial debundling of the SWCNTs. A reversible periodic swelling and shrinking during cycling is observed for both materials, with the magnitude of expansion depending on the type of ions forming the double layer.

  18. Cr(VI) adsorption on functionalized amorphous and mesoporous silica from aqueous and non-aqueous media

    International Nuclear Information System (INIS)

    Perez-Quintanilla, Damian; Hierro, Isabel del; Fajardo, Mariano; Sierra, Isabel

    2007-01-01

    A mesoporous silica (SBA-15) and amorphous silica (SG) have been chemically modified with 2-mercaptopyridine using the homogeneous route. This synthetic route involved the reaction of 2-mercaptopyridine with 3-chloropropyltriethoxysilane prior to immobilization on the support. The resulting material has been characterized by powder X-ray diffraction, nitrogen gas sorption, FT-IR and MAS NMR spectroscopy, thermogravimetry and elemental analysis. The solid was employed as a Cr(VI) adsorbent from aqueous and non-aqueous solutions at room temperature. The effect of several variables (stirring time, pH, metal concentration and solvent polarity) has been studied using the batch technique. The results indicate that under the optimum conditions, the maximum adsorption value for Cr(VI) was 1.83 ± 0.03 mmol/g for MP-SBA-15, whereas the adsorption capacity of the MP-SG was 0.86 ± 0.02 mmol/g. On the basis of these results, it can be concluded that it is possible to modify chemically SBA-15 and SG with 2-mercaptopyridine and to use the resulting modified silicas as effective adsorbents for Cr(VI)

  19. Non-aqueous capillary electrophoresis with red light emitting diode absorbance detection for the analysis of basic dyes.

    Science.gov (United States)

    Fakhari, Ali Reza; Breadmore, Michael C; Macka, Miroslav; Haddad, Paul R

    2006-11-24

    Non-aqueous capillary electrophoresis was evaluated for the separation of five hydrophobic basic blue dyes for application in forensic dye analysis. The use of a red light emitting diode as a high intensity, low-noise light source provided sensitive detection of the blue dyes while also allowing the evaluation of solvents that absorb strongly in the UV region. Excellent peak shapes and separation selectivity were obtained in methanol, ethanol, acetonitrile and dimethylsulfoxide, however water, tetrahydrofuran, dimethylformamide and acetone were unsuitable as solvents due to poor peak shapes and a lack of sensitivity, most likely due to adsorption onto the capillary wall. Due to the known compatibility of methanol with capillary electrophoresis-mass spectrometry, this solvent was examined further with the relative acidity/basicity of the electrolyte being optimised with an artificial neural network. The optimised method was examined for the separation of ink samples from 6 fibre tip and 2 ball point blue or black pens and showed that a unique migration time for the main dye component in seven of the eight pens could be obtained.

  20. Evaluation of kinetic parameters of 1, 1'-dibenzoylferrocene in non aqueous methanol solution by cyclic voltammetry (abstract)

    International Nuclear Information System (INIS)

    Parveen, R.; Kirmani, M.Z.; Naqvi, I.I.

    2011-01-01

    The electrochemical Kinetic study of 1, 1/sup '/- Dibenzoylferrocene (DBF) at a platinum working electrode in 0.1 mol dm/sup -3/ NaClO/sub 4/ non aqueous medium has been studied by Cyclic voltammetry. The heterogeneous electron transfer rate constants (ks) and the diffusion coefficients (Do) of DBF were estimated at various temperatures (283 - 323 K) and at different scan rates (0.05 - 0.5 V s/sup -1/). A calibration curve, linear over the range of 1 X 10/sup -3/ - 9 X 10/sup -3/ mol dm/sup -3/ ,was plotted at the scan rate of 0.25 Vs/sup -1/. This plot can be used to analyze an unknown sample of the compound. The kinetic data was also used to evaluate the Activation energy (Ea). The thermodynamic parameters such as enthalpy change of activation (delta H/sup */), Entropy change (delta S/sup */) and Gibbs free energy change (delta GH/sup */) were also investigated during the study. (author)

  1. Solvating additives drive solution-mediated electrochemistry and enhance toroid growth in non-aqueous Li-O2 batteries

    Science.gov (United States)

    Aetukuri, Nagaphani B.; McCloskey, Bryan D.; García, Jeannette M.; Krupp, Leslie E.; Viswanathan, Venkatasubramanian; Luntz, Alan C.

    2015-01-01

    Given their high theoretical specific energy, lithium-oxygen batteries have received enormous attention as possible alternatives to current state-of-the-art rechargeable Li-ion batteries. However, the maximum discharge capacity in non-aqueous lithium-oxygen batteries is limited to a small fraction of its theoretical value due to the build-up of insulating lithium peroxide (Li2O2), the battery’s primary discharge product. The discharge capacity can be increased if Li2O2 forms as large toroidal particles rather than as a thin conformal layer. Here, we show that trace amounts of electrolyte additives, such as H2O, enhance the formation of Li2O2 toroids and result in significant improvements in capacity. Our experimental observations and a growth model show that the solvating properties of the additives prompt a solution-based mechanism that is responsible for the growth of Li2O2 toroids. We present a general formalism describing an additive’s tendency to trigger the solution process, providing a rational design route for electrolytes that afford larger lithium-oxygen battery capacities.

  2. Thermal-hydraulic analysis of graphite tubes for the non-aqueous system of accelerator transmutation of nuclear waste

    International Nuclear Information System (INIS)

    Potter, R.C.; Venneri, F.; Trujillo, D.A.

    1993-01-01

    Accelerator transmutation of nuclear waste offers exciting possibilities for the disposal of nuclear waste by converting it into more benign Species. The non-aqueous system discussed here contains the materials to be transmuted within a lithium-fluoride salt. The system consists of bundles of graphite tubes containing the salt Solution. The tubes are cooled as lithium flows across their exterior. These circular graphite tubes have an inner circular passage and an outer annulus. Natural convection within the tubes causes the salt to circulate. This paper deals with the thermal-hydraulics of the system; it does not consider the neutronics in detail. Heat transfer and fluid flow were modeled using a custom computer program the system behavior of an graphite tube. Different geometries were tried, while keeping the system volume the same, to determine an optimize graphite tube geometry. I considered both the parallel flow and the counterflow of the lithium coolant, and allowed limited boiling to occur to facilitate circulation. I achieved power densities as high as 200 W/cm 3 for the overall blanket

  3. One-step isolation of γ-oryzanol from rice bran oil by non-aqueous hydrostatic countercurrent chromatography.

    Science.gov (United States)

    Angelis, Apostolis; Urbain, Aurélie; Halabalaki, Maria; Aligiannis, Nektarios; Skaltsounis, Alexios-Leandros

    2011-09-01

    The value-added γ-oryzanol was purified in one step from crude rice bran oil (RBO) using a preparative hydrostatic countercurrent chromatography (hydrostatic CCC) method, operating in the dual mode. The fractionation was performed using a non-aqueous biphasic solvent system consisting of heptane-acetonitrile-butanol (1.8:1.4:0.7, v/v/v), leading rapidly to the target compounds. Transfer of the analytical CCC method to large-scale isolation was also carried out yielding a high quantity-high purity fraction of γ-oryzanol. In addition, a fraction of hydroxylated triterpene alcohol ferulates (polar γ-oryzanol) was clearly separated and obtained. Furthermore, a fast HPLC-APCI(±)-HRMS method was developed and applied for the identification of γ-oryzanol as well as the polar γ-oryzanol in RBO and the resulting fractions. The purity of γ-oryzanol fraction was estimated as 97% based on HPLC-APCI-HRMS analysis. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Preparation and evaluation of icariside II-loaded binary mixed micelles using Solutol HS15 and Pluronic F127 as carriers.

    Science.gov (United States)

    Hou, Jian; Wang, Jing; Sun, E; Yang, Lei; Yan, Hong-Mei; Jia, Xiao-Bin; Zhang, Zhen-Hai

    2016-11-01

    An effective anti-cancer drug, icariside II (IS), has been used to treat a variety of cancers in vitro. However, its poor aqueous solubility and permeability lead to low oral bioavailability. The aim of this work was to use Solutol®HS15 and Pluronic F127 as surfactants to develop novel mixed micelles to enhance the oral bioavailability of IS by improving permeability and inhibiting efflux. The IS-loaded mixed micelles were prepared using the method of ethanol thin-film hydration. The physicochemical properties, dissolution property, oral bioavailability of the male SD rats, permeability and efflux of Caco-2 transport models, and gastrointestinal safety of the mixed micelles were evaluated. The optimized IS-loaded mixed micelles showed that at 4:1 ratio of Solutol®HS15 and Pluronic F127, the particle size was 12.88 nm with an acceptable polydispersity index of 0.172. Entrapment efficiency (94.6%) and drug loading (9.7%) contributed to the high solubility (11.7 mg/mL in water) of IS, which increased about 900-fold. The SF-IS mixed micelle release profile showed a better sustained release property than that of IS. In Caco-2 cell monolayer models, the efflux ratio dramatically decreased by 83.5%, and the relative bioavailability of the mixed micelles (AUC 0-∞ ) compared with that of IS (AUC 0-∞ ) was 317%, indicating potential for clinical application. In addition, a gastrointestinal safety assay also provided reliable clinical evidence for the safe use of this micelle.

  5. Mixed hyperfine interaction - a tool to investigate the short range order and the strange magnetic behaviour of amorphous Fe-based binary alloys

    International Nuclear Information System (INIS)

    Fries, S.M.; Crummenauer, J.; Gonser, U.; Schaaf, P.; Chien, C.L.

    1989-01-01

    The Moessbauer study of the mixed magnetic dipole and electric quadrupole interaction in the paramagnetic state of amorphous Fe-Zr and Fe-Hf alloys is presented. Strong evidence for chemical short range order of the iron-pure alloys is found. The hyperfine parameters of the iron-rich alloys are marked by a complex applied field and temperature dependence, suggesting a not negligible spin-correlation well above Tc. (orig.)

  6. Refinement of the Kansas City Plant site conceptual model with respect to dense non-aqueous phase liquids (DNAPL)

    International Nuclear Information System (INIS)

    Korte, N.E.; Hall, S.C.; Baker, J.L.

    1995-01-01

    This document presents a refinement of the site conceptual model with respect to dense non-aqueous phase liquid (DNAPL) at the US Department of Energy Kansas City Plant (KCP). This refinement was prompted by a review of the literature and the results of a limited study that was conducted to evaluate whether pools of DNAPL were present in contaminated locations at the KCP. The field study relied on the micropurge method of sample collection. This method has been demonstrated as a successful approach for obtaining discrete samples within a limited aquifer zone. Samples were collected at five locations across 5-ft well screens located at the base of the alluvial aquifer at the KCP. The hypothesis was that if pools of DNAPL were present, the dissolved concentration would increase with depth. Four wells with highly contaminated groundwater were selected for the test. Three of the wells were located in areas where DNAPL was suspected, and one where no DNAPL was believed to be present. The results demonstrated no discernible pattern with depth for the four wells tested. A review of the data in light of the available technical literature suggests that the fine-grained nature of the aquifer materials precludes the formation of pools. Instead, DNAPL is trapped as discontinuous ganglia that are probably widespread throughout the aquifer. The discontinuous nature of the DNAPL distribution prevents the collection of groundwater samples with concentrations approaching saturation. Furthermore, the results indicate that attempts to remediate the aquifer with conventional approaches will not result in restoration to pristine conditions because the tortuous groundwater flow paths will inhibit the efficiency of fluid-flow-based treatments

  7. Numerical investigation of a non-aqueous lithium-oxygen battery based on lithium superoxide as the discharge product

    International Nuclear Information System (INIS)

    Tan, Peng; Ni, Meng; Shao, Zongping; Chen, Bin; Kong, Wei

    2017-01-01

    Highlights: •A macroscopic model for Li-O 2 batteries based on LiO 2 is developed. •The electrode and electrolyte properties on discharge behaviors are investigated. •A thin cathode with a large porosity is favorable for a high specific capacity. •A high catalytic activity can lead to a high discharge voltage. •The oxygen solubility has larger impacts on the discharge performance. -- Abstract: It is reported lithium superoxide as the discharge product can largely decrease the charge voltage and enable a high round-trip efficiency of lithium-oxygen (Li-O 2 ) batteries. Here, we conduct a numerical investigation of the discharge behaviors of such batteries with LiO 2 as the discharge product. A mathematical model considering the mass transport and electrochemical reaction processes is first developed, which gives good agreement of the simulated discharge voltage with the experimental data. Then, with this model, the effects of electrode and electrolyte properties on the discharge performance are detailedly investigated. It is found that a thin cathode with a large porosity is favorable for a high specific capacity, and a high catalytic activity can lead to a high discharge voltage. For the cathode with different geometrical properties, it is found that the oxygen solubility and diffusivity have similar impacts on discharge capacities, but the oxygen solubility has a larger impact on energy densities. Besides, the limitations and further developments of the present model are also discussed. The results obtained from this work may give useful guidance for the discharge performance improvements of non-aqueous Li-O 2 batteries, and provide implications for other energy storage systems with solid product formation such as Na-O 2 batteries and Li-S batteries.

  8. Evaluation of Skin Penetration of Diclofenac from a Novel Topical Non Aqueous Solution: A Comparative Bioavailability Study.

    Science.gov (United States)

    Nivsarkar, Manish; Maroo, Sanjaykumar H; Patel, Ketan R; Patel, Dixit D

    2015-12-01

    Different topical formulations of diclofenac have varying skin penetration profile. Recent advances in science and technology has led to the development of many new formulations of drugs for topical drug delivery. One such technological development has led to the innovation of Dynapar QPS, a novel, non-aqueous, quick penetrating solution (QPS) of diclofenac diethylamine. This study was aimed to measure the total exposure from the drug penetrating the skin in healthy human subjects and comparing the relative systemic bioavailability of Dynapar QPS(®) with diclofenac emulgel. A 200 mg of diclofenac from either Dynapar QPS(®) (5 ml) or emulgel (20 g) was applied on back of subject as per the randomisation schedule. Blood samples were collected up to 16 hours post drug application. Plasma concentration of diclofenac was measured by pre-validated HPLC method. Pharmacokinetic (PK) parameters like Cmax, Tmax, t1/2, AUC0-t, AUC0-∞, and Kel, of diclofenac were determined for both the formulations. Mean Cmax after administration of Dynapar QPS(®) and diclofenac emulgel were 175.93 and 40.04 ng/ml, respectively. Tmax of diclofenac was almost half with QPS compared to emulgel (5.24 hrs versus 9.53 hrs respectively). The mean AUC0-t and AUC0-∞ after administration of Dynapar QPS(®) was higher as compared to diclofenac emulgel (AUC0-t: 1224.19 versus 289.78 ng.h/ml, respectively; AUC0-∞: 1718.21 versus 513.83 ng.h/ml, respectively). None of the subject experienced any adverse event during the study. The results indicate an enhanced penetration and subsequent absorption of diclofenac from Dynapar QPS(®) as compared to diclofenac emulgel. Higher penetration is likely to translate into better pain relief in patients.

  9. Cobalt and Vanadium Trimetaphosphate Polyanions: Synthesis, Characterization, and Electrochemical Evaluation for Non-aqueous Redox-Flow Battery Applications.

    Science.gov (United States)

    Stauber, Julia M; Zhang, Shiyu; Gvozdik, Nataliya; Jiang, Yanfeng; Avena, Laura; Stevenson, Keith J; Cummins, Christopher C

    2018-01-17

    An electrochemical cell consisting of cobalt ([Co II/III (P 3 O 9 ) 2 ] 4-/3- ) and vanadium ([V III/II (P 3 O 9 ) 2 ] 3-/4- ) bistrimetaphosphate complexes as catholyte and anolyte species, respectively, was constructed with a cell voltage of 2.4 V and Coulombic efficiencies >90% for up to 100 total cycles. The [Co(P 3 O 9 ) 2 ] 4- (1) and [V(P 3 O 9 ) 2 ] 3- (2) complexes have favorable properties for flow-battery applications, including reversible redox chemistry, high stability toward electrochemical cycling, and high solubility in MeCN (1.09 ± 0.02 M, [PPN] 4 [1]·2MeCN; 0.77 ± 0.06 M, [PPN] 3 [2]·DME). The [PPN] 4 [1]·2MeCN and [PPN] 3 [2]·DME salts were isolated as crystalline solids in 82 and 68% yields, respectively, and characterized by 31 P NMR, UV/vis, ESI-MS(-), and IR spectroscopy. The [PPN] 4 [1]·2MeCN salt was also structurally characterized, crystallizing in the monoclinic P2 1 /c space group. Treatment of 1 with [(p-BrC 6 H 4 ) 3 N] + allowed for isolation of the one-electron-oxidized spin-crossover (SCO) complex, [Co(P 3 O 9 ) 2 ] 3- (3), which is the active catholyte species generated during cell charging. The success of the 1-2 cell provides a promising entry point to a potential future class of transition-metal metaphosphate-based all-inorganic non-aqueous redox-flow battery electrolytes.

  10. Bi-functional effects of lengthening aliphatic chain of phthalimide-based negative redox couple and its non-aqueous flow battery performance at stack cell

    Directory of Open Access Journals (Sweden)

    Hyun-seung Kim

    2018-04-01

    Full Text Available Effects of lengthening an aliphatic chain of a phthalimide-based negative redox couple for non-aqueous flow batteries are examined. The working voltage and solubility of N-butylphthalimide are 0.1 V lower and four times greater (2.0 M than those of methyl-substituted phthalimide. These enhanced properties are attributed to a lower packing density. Consequently, the energy density of the proposed redox couple is greatly enhanced from butyl substitution. Furthermore, the results of the stack flow cell test with N,N,N′,N′-tetramethyl-p-phenylenediamine positive redox couple show advantageous features of this non-aqueous flow battery system: a stable Coulombic efficiency and high working voltage.

  11. Bi-functional effects of lengthening aliphatic chain of phthalimide-based negative redox couple and its non-aqueous flow battery performance at stack cell

    Science.gov (United States)

    Kim, Hyun-seung; Hwang, Seunghae; Kim, Youngjin; Ryu, Ji Heon; Oh, Seung M.; Kim, Ki Jae

    2018-04-01

    Effects of lengthening an aliphatic chain of a phthalimide-based negative redox couple for non-aqueous flow batteries are examined. The working voltage and solubility of N-butylphthalimide are 0.1 V lower and four times greater (2.0 M) than those of methyl-substituted phthalimide. These enhanced properties are attributed to a lower packing density. Consequently, the energy density of the proposed redox couple is greatly enhanced from butyl substitution. Furthermore, the results of the stack flow cell test with N,N,N',N'-tetramethyl-p-phenylenediamine positive redox couple show advantageous features of this non-aqueous flow battery system: a stable Coulombic efficiency and high working voltage.

  12. Modeling Learning in Doubly Multilevel Binary Longitudinal Data Using Generalized Linear Mixed Models: An Application to Measuring and Explaining Word Learning.

    Science.gov (United States)

    Cho, Sun-Joo; Goodwin, Amanda P

    2016-04-01

    When word learning is supported by instruction in experimental studies for adolescents, word knowledge outcomes tend to be collected from complex data structure, such as multiple aspects of word knowledge, multilevel reader data, multilevel item data, longitudinal design, and multiple groups. This study illustrates how generalized linear mixed models can be used to measure and explain word learning for data having such complexity. Results from this application provide deeper understanding of word knowledge than could be attained from simpler models and show that word knowledge is multidimensional and depends on word characteristics and instructional contexts.

  13. Determination of Three-Dimensional Morphology and Inner Structure of Second-Phase Inclusions in Metals by Non-Aqueous Solution Electrolytic and Room Temperature Organic Methods

    OpenAIRE

    Jing Guo; Keming Fang; Hanjie Guo; Yiwa Luo; Shengchao Duan; Xiao Shi; Wensheng Yang

    2018-01-01

    The secondary-phase particles in metals, particularly those composed of non-metallic materials, are often detrimental to the mechanical properties of metals; thus, it is crucial to control inclusion formation and growth. One of the challenges is determining the three-dimensional morphology and inner structures of such inclusions. In this study, a non-aqueous solution electrolytic method and a room-temperature organic technique were developed based on the principle of electrochemistry to deter...

  14. Highly-dispersed Ta-oxide catalysts prepared by electrodeposition in a non-aqueous plating bath for polymer electrolyte fuel cell cathodes

    KAUST Repository

    Seo, Jeongsuk; Cha, Dong Kyu; Takanabe, Kazuhiro; Kubota, Jun; Domen, Kazunari

    2012-01-01

    The Ta-oxide cathode catalysts were prepared by electrodeposition in a non-aqueous solution. These catalysts showed excellent catalytic activity and have an onset potential of 0.92 V RHE for the oxygen reduction reaction (ORR). The highly-dispersed Ta species at the nanometer scale on the carbon black was an important contributor to the high activity. © 2012 The Royal Society of Chemistry.

  15. Development and validation of alternative methods by non-aqueous acid-base titration and derivative ultraviolet spectrophotometry for quantification of sildenafil in raw material and tablets

    Directory of Open Access Journals (Sweden)

    Taízia Dutra Silva

    2017-04-01

    Full Text Available Sildenafil citrate (SILC is a potent phosphodiesterase-5 inhibitor used for erectile dysfunction and pulmonary hypertension. This study shows two simple, fast and alternative analytical methods for SILC determination by non-aqueous titration and by derivative ultraviolet spectrophotometry (DUS in active pharmaceutical ingredient and/or dosage forms. The quantitation method of SILC active pharmaceutical ingredient by non-aqueous acid-base titration was developed using methanol as solvent and 0.1 mol/L of perchloric acid in acetic acid as titrant. The endpoint was potentiometrically detected. The non-aqueous titration method shows satisfactory repeatability and intermediate precision (RSD 0.70-1.09%. The neutralization reaction occurred in the stoichiometric ratio 1:1 in methanol. The determination of SILC active pharmaceutical ingredient or dosage forms by DUS was developed in the linear range from 10 to 40 µg/mL, in 0.01 mol/L HCl, using the first order zero-peak method at λ 256 nm. The DUS method shows selectivity toward tablets excipients, appropriate linearity (R2 0.9996, trueness (recovery range 98.86-99.30%, repeatability and intermediate precision in three concentration levels (RSD 1.17-1.28%; 1.29-1.71%, respectively. Therefore, the methods developed are excellent alternatives to sophisticated instrumental methods and can be easily applied in any pharmaceutical laboratory routine due to simple and fast executions.

  16. Passivation behavior of Type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF6 salt

    International Nuclear Information System (INIS)

    Myung, Seung-Taek; Sasaki, Yusuke; Saito, Takamitsu; Sun, Yang-Kook; Yashiro, Hitoshi

    2009-01-01

    Passivation behavior of type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF 6 salt was studied using electrochemical polarization, X-ray photoelectron spectroscopy (XPS) and time of flight-secondary ion mass spectroscopy (ToF-SIMS). Cathodic polarization to 0 V vs. Li/Li + resulted in most but not complete reduction of the air-formed film from oxides to metal on the stainless steel, as confirmed by XPS. For complete elimination of the air-formed film, the surface of the stainless steel was scratched under anodic polarization conditions. At 3 V vs. Li/Li + where an anodic current peak appeared, only an indistinct layer was recognized on the newly scratched surface, according to ToF-SIMS analysis. Above 4 V vs. Li/Li + , substantial passive films were formed, which were composed of oxides and fluorides of iron and chromium. The origin of oxide was due to water contained in the non-aqueous alkyl carbonate solution, and that of fluorides were the result of the decomposition of electrolytic salt, LiPF 6 , especially at higher potential. The resultant passive films were stable in the non-aqueous alkyl carbonate solution containing LiPF 6 salt.

  17. 1,3-Dioxolane, tetrahydrofuran, acetylacetone and dimethyl sulfoxide as solvents for non-aqueous vanadium acetylacetonate redox-flow-batteries

    International Nuclear Information System (INIS)

    Herr, T.; Noack, J.; Fischer, P.; Tübke, J.

    2013-01-01

    Highlights: • Four solvents were employed in a non-aqueous redox flow battery system. • Coulombic efficiencies of 85.9–98.5% and energy efficiencies of 26.6–43.6% were achieved. • Discharge power density was enhanced up to 0.080 mW cm −2 . • Solubility of V(acac) 3 was increased to 0.8 M compared to the acetonitrile system. -- Abstract: A non-aqueous vanadium acetylacetonate redox flow battery with different organic solvents and tetrabutylammonium hexafluorophosphate has been investigated. Cyclic voltammograms show three redox couples in 1,3-dioxolane, tetrahydrofuran, acetylacetone and two redox couples in dimethyl sulfoxide. Cell potentials between 2.21 and 2.61 V are measured, depending on the solvent used. Impedance Spectroscopy has been used to determine rate limiting step in the non-aqueous redox flow battery. Experiments in a charge–discharge test cell yielded coulombic and energy efficiencies of 85.9–98.5% and 26.6–43.6%, respectively

  18. Improved oral bioavailability and anticancer efficacy on breast cancer of paclitaxel via Novel Soluplus(®)-Solutol(®) HS15 binary mixed micelles system.

    Science.gov (United States)

    Hou, Jian; Sun, E; Sun, Congyong; Wang, Jing; Yang, Lei; Jia, Xiao-Bin; Zhang, Zhen-Hai

    2016-10-15

    The aim of this study was to develop a novel drug delivery system using two biocompatible copolymers of Solutol(®)HS15 and Soluplus(®) to improve solubility, oral bioavailability and anticancer activity of paclitaxel (PTX). The PTX-loaded mixed micelles (PTX-M) were prepared by ethanol thin-film hydration method. The optimal PTX-M were provided with small size (164.8±2.0nm) and spherical shape at ratio of 1: 3 (Solutol(®)HS15: Soluplus(®)), thus increasing the solubility to 15.76±0.15mg/mL in water. The entrapment efficiency and drug loading of PTX-M were 98.48±0.91% and 10.59±0.09% respectively. In vitro release study indicated a sustained release of PTX-M. Transcellular transport study showed that the efflux ratio were decreased by 89.72% dramatically in Caco-2 cell transport models, and the pharmacokinetics study of PTX-M compared with PTX, showed a 3.68-fold increase in relative oral bioavailability, indicating the mixed micelles may promote absorption in the gastrointestinal tract. In addition, the MTT assay demonstrated that the IC50 value of PTX-M was reduced by 40.21% (PTX-M: 22.6±2.1μg/mL, PTX: 37.8±1.4μg/mL), and in vivo anti-tumor study (15days' therapy) showed PTX-M achieved higher anti-tumor efficacy (57.66%) compared with PTX (41.13%). Furthermore, a gastrointestinal safety assay also provided the reliability and safety of PTX-M. Collectively, these findings present an oral micelle formulation with increased solubility, oral bioavailability and anticancer activity of PTX. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Reductive dechlorination of chlorinated hydrocarbons as non-aqueous phase liquid (NAPL): Preliminary investigation on effects of cement doses

    Energy Technology Data Exchange (ETDEWEB)

    Do, Si-Hyun, E-mail: sihyun2@hanyang.ac.kr [Department of Chemical Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Batchelor, Bill [Zachry Department of Civil Engineering, Texas A and M University, College Station, TX 77843 (United States)

    2012-07-15

    The reactivities of various types of iron mixtures to degrade chlorinated hydrocarbons (PCE, TCE and 1,1,1-TCA) in the form of non-aqueous phase liquids were investigated. The iron mixtures included a mixture of Fe(II) and Portland cement (Fe(II)-C), a mixture of Fe(II), Fe(III) and Ca(OH){sub 2} (Fe(II/III)-L), and a mixture of Fe(II), Fe(III), Ca(OH){sub 2}, and Portland cement (Fe(II/III)-C). When the same amount of Fe(II) was used, Fe(II)-C was more reactive with chlorinated ethylenes (i.e. PCE and TCE) than Fe(II/III)-L. The reductive pathway for high concentrations of total PCE (i.e. above solubility) with Fe(II)-C was determined to be a combination of two-electron transfer, {beta}-elimination and hydrogenolysis. Increasing the cement dose from 5% to 10% in Fe(II)-C did not affect PCE dechlorination rates, but it did favor the {beta}-elimination pathway. In addition, when Fe(II/III)-C with 5%C was used, PCE dechlorination was similar to that by Fe(II)-C, but this mixture did not effectively degrade TCE. A modified second-order kinetic model was developed and shown to appropriately describe degradation of TCE at high concentrations. Fe(II/III)-L effectively degraded high concentrations of 1,1,1-TCA at rates that were similar to those obtained with Fe(II)-C using 10% C. Moreover, both increasing cement doses and the presence of Fe(III) increased dechlorination rates of 1,1,1-TCA, which was mainly through the hydrogenolysis pathway. The reactivity of Fe(II/III)-L was strongly dependent on the target compound (i.e. less reactivity with TCE, more with 1,1,1-TCA). Therefore, Fe(II/III)-L could be a potential mixture for degrading 1,1,1-TCA, but it should be modified to degrade TCE more effectively. - Highlights: Black-Right-Pointing-Pointer TCE yield indicated that PCE dechlorination was through hydrogenolysis and {beta}-elimination. Black-Right-Pointing-Pointer {beta}-elimination, especially PCE to dichloroacetylene, was favored with the higher cement doses. Black

  20. Mixed micelles of sodium cholate and sodium dodecylsulphate 1:1 binary mixture at different temperatures--experimental and theoretical investigations.

    Directory of Open Access Journals (Sweden)

    Balázs Jójárt

    Full Text Available Micellisation process for sodium dodecyl sulphate and sodium cholate in 1∶1 molar ratio was investigated in a combined approach, including several experimental methods and coarse grained molecular dynamics simulation. The critical micelle concentration (cmc of mixed micelle was determined by spectrofluorimetric and surface tension measurements in the temperature range of 0-50°C and the values obtained agreed with each other within the statistical error of the measurements. In range of 0-25°C the cmc values obtained are temperature independent while cmc values were increased at higher temperature, which can be explained by the intensive motion of the monomers due to increased temperature. The evidence of existing synergistic effect among different constituent units of the micelle is indicated clearly by the interaction parameter (β1,2 calculated from cmc values according to Rubingh. As the results of the conductivity measurements showed the negative surface charges of the SDS-NaCA micelle are not neutralized by counterions. Applying a 10 µs long coarse-grained molecular dynamics simulation for system including 30-30 SDS and CA (with appropriate number of Na+ cations and water molecules we obtained semi-quantitative agreement with the experimental results. Spontaneous aggregation of the surfactant molecules was obtained and the key steps of the micelle formation are identified: First a stable SDS core was formed and thereafter due to the entering CA molecules the size of the micelle increased and the SDS content decreased. In addition the size distribution and composition as well as the shape and structure of micelles are also discussed.

  1. Initial solubility & density evaluation of Non-Aqueous system of amino acid salts for CO2 capture: potassium prolinate blended with ethanol and ethylene glycol

    Science.gov (United States)

    Murshid, Ghulam; Garg, Sahil

    2018-05-01

    Amine scrubbing is the state of the art technology for CO2 capture, and solvent selection can significantly reduce the capital and energy cost of the process. Higher energy requirement for aqueous amine based CO2 removal process is still a most important downside preventive its industrial deployment. Therefore, in this study, novel non-aqueous based amino acid salt system consisting of potassium prolinate, ethanol and ethylene glycol has been studied. This work presents initial CO2 solubility study and important physical properties i.e. density of the studied solvent system. Previous work showed that non-aqueous system of potassium prolinate and ethanol has good absorption rates and requires lower energy for solvent regeneration. However, during regeneration, solvent loss issues were found due to lower boiling point of the ethanol. Therefore, ethylene glycol was added into current studied system for enhancing the overall boiling point of the system. The good initial CO2 solubility and low density of studied solvent system offers several advantages as compared to conventional amine solutions.

  2. A comparative study on the solubility and stability of p-phenylenediamine-based organic redox couples for non-aqueous flow batteries

    Science.gov (United States)

    Kim, Hyun-seung; Lee, Keon-Joon; Han, Young-Kyu; Ryu, Ji Heon; Oh, Seung M.

    2017-04-01

    A methyl-substituted p-phenylenediamine (PD), N,N,N‧,N‧-tetramethyl-p-phenylenediamine (TMPD), is examined as a positive redox couple with high energy density for non-aqueous Li-flow batteries. Methyl substitution affects the solubility of the redox couple, as the solubility is increased by a factor of ten, to a maximum solubility of 5.0 M in 1.0 M lithium tetrafluoroborate-propylene carbonate supporting electrolyte due to elimination of the hydrogen bonding between the solute molecules. The methyl substitution also enhances the chemical stability of the cation radical and di-cation being generated from PD, as the redox center is shielded by the methyl groups. Furthermore, this organic redox couple demonstrate two-electron redox reactions at 3.2 and 3.8 V (vs. Li/Li+); therefore, the volumetric capacity is twice higher compared to conventional one-electron involved redox couples. In a non-flowing Li/TMPD coin-cell, this organic redox couple demonstrates very stable cycleability as a positive redox couple for non-aqueous flow batteries.

  3. Novel composite membrane coated with a poly(diallyldimethylammonium chloride)/urushi semi-interpenetrating polymer network for non-aqueous redox flow battery application

    Science.gov (United States)

    Cho, Eunhae; Won, Jongok

    2016-12-01

    Novel composite membranes of a semi-interpenetrating network (semi-IPN) coated on the surfaces of a porous Celgard 2400 support are prepared and investigate for application in a non-aqueous redox flow battery (RFB). A natural polymer, urushi, is used for the matrix because of its high mechanical robustness, and poly(diallyldimethylammonium chloride) (PDDA) provides anionic exchange sites. The PDDA/urushi (P/U) semi-IPN film is prepared by the photo polymerization of urushiol in the presence of PDDA. The thin layer composed of the P/U semi-IPN on the porous support provides selectivity while maintaining the ion conductivity. The coulombic and energy efficiencies increase with increasing amounts of PDDA in the P/U semi-IPN layer, and the values reach 69.5% and 42.5%, respectively, for the one containing 40 wt% of PDDA. These values are substantially higher than those of the Neosepta AHA membrane and the Celgard membrane, indicating that the selective layer reduces the crossover of the redox active species through the membrane. This result implies that the formation of composite membranes using semi-IPN selective layers on the dimensionally stable porous membrane enable the successful use of a non-aqueous RFB for future energy storage systems.

  4. The radiation-induced inactivation of microorganisms in non-aqueous suspension: The effect of selective alcohols and paraffins on the radiation sensitivity of aerated Bacillus pumilus spores

    International Nuclear Information System (INIS)

    Jacobs, G.P.

    1981-01-01

    The effect of model compounds comprising alcohols and paraffins on the radiation sensitivity of B. pumilus spores has been studied with the aim of understanding the radiation-induced inactivation of microorganisms when suspended in non-aqueous medium. This study is a prerequisite to the undertaking of radiation sterilization of non-aqueous pharmaceuticals. Spores of B. pumilus E601 mounted on kaolin powder were suspended in the appropriate organic agent and gamma irradiated under oxic conditions. Spores suspended in paraffins displayed increased radiation response over that for aerated buffered suspensions. Values of inactivation constant ranged between 2 x and 5 x that for buffer. Less pronounced modification of response was obtained for the alcohols. The results reveal a marked tendency for response to increase with decreasing polarity of the supending fluid. The partial miscibility of the alcohols in water enabled the examining of the transition from the response characteristic of aerated buffered suspensions to those of the spores in pure organic liquids. (orig./MG) [de

  5. Solving a binary puzzle

    NARCIS (Netherlands)

    Utomo, P.H.; Makarim, R.H.

    2017-01-01

    A Binary puzzle is a Sudoku-like puzzle with values in each cell taken from the set {0,1} {0,1}. Let n≥4 be an even integer, a solved binary puzzle is an n×n binary array that satisfies the following conditions: (1) no three consecutive ones and no three consecutive zeros in each row and each

  6. Eclipsing binaries in open clusters

    DEFF Research Database (Denmark)

    Southworth, John; Clausen, J.V.

    2006-01-01

    Stars: fundamental parameters - Stars : binaries : eclipsing - Stars: Binaries: spectroscopic - Open clusters and ass. : general Udgivelsesdato: 5 August......Stars: fundamental parameters - Stars : binaries : eclipsing - Stars: Binaries: spectroscopic - Open clusters and ass. : general Udgivelsesdato: 5 August...

  7. Communication: The influence of CO2 poisoning on overvoltages and discharge capacity in non-aqueous Li-Air batteries

    DEFF Research Database (Denmark)

    Mekonnen, Yedilfana Setarge; Knudsen, Kristian Bastholm; Mýrdal, Jón Steinar Garðarsson

    2014-01-01

    The effects of Li2CO3 like species originating from reactions between CO2 and Li2O2 at the cathode of non-aqueous Li-air batteries were studied by density functional theory (DFT) and galvanostatic charge-discharge measurements. Adsorption energies of CO2 at various nucleation sites on a stepped (1......‾100) Li2O2 surface were determined and even a low concentration of CO2 effectively blocks the step nucleation site and alters the Li2O2 shape due to Li2CO3 formation. Nudged elastic band calculations show that once CO2 is adsorbed on a step valley site, it is effectively unable to diffuse and impacts...

  8. Effects of precursor on the morphology and size of ZrO2 nanoparticles, synthesized by sol-gel method in non-aqueous medium

    International Nuclear Information System (INIS)

    Siddiqui, Mohammed Rafiq Hussain; Al-Wassil, Abdulaziz Ibrahim; Mahfouz, Refaat Mohamad; Al-Otaibi, Abdullah Mohmmed

    2012-01-01

    Pure zirconium oxide (ZrO 2 ) nanoparticles with diameters 10-25 nm were synthesized from ZrOCl 2 .8H 2 O and Zr(SO 4 )2.H 2 O with benzyl alcohol as non-aqueous solvent medium using sol-gel method. Sodium lauryl sulfate was added as surfactants to control the particle size. The synthesized ZrO 2 nanoparticles have a mixture of tetragonal and monoclinic structure. The XRD showed the purity of obtained ZrO 2 nanoparticles with tetragonal and monoclinic phase and the crystallite size for ZrOCl 2 .8H 2 O precursor was estimated to be 18.1 nm and that from Zr(SO 4 )2.H 2 O was 9.7 nm. The transmission electron microscopy and scanning electron microscopic studies also shows different sizes of nanoparticles and different morphology depending on the precursor used for the synthesis of ZrO 2 nanoparticles. (author)

  9. Electrical conductivity in Li2O2 and its role in determining capacity limitations in non-aqueous Li-O2 batteries

    DEFF Research Database (Denmark)

    Viswanathan, V.; Thygesen, Kristian Sommer; Hummelshøj, J.S.

    2011-01-01

    Non-aqueous Li-air or Li-O2 cells show considerable promise as a very high energy density battery couple. Such cells, however, show sudden death at capacities far below their theoretical capacity and this, among other problems, limits their practicality. In this paper, we show that this sudden...... death arises from limited charge transport through the growing Li 2O2 film to the Li2O2-electrolyte interface, and this limitation defines a critical film thickness, above which it is not possible to support electrochemistry at the Li2O 2-electrolyte interface. We report both electrochemical experiments...... using a reversible internal redox couple and a first principles metal-insulator-metal charge transport model to probe the electrical conductivity through Li2O2 films produced during Li-O 2 discharge. Both experiment and theory show a sudden death in charge transport when film thickness is ∼5 to 10 nm...

  10. Bench-Scale Development of a Non-Aqueous Solvent (NAS) CO2 Capture Process for Coal-Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lail, Marty

    2017-09-12

    The project aimed to advance RTI’s non-aqueous amine solvent technology by improving the solvent to reduce volatility, demonstrating long-term continuous operation at lab- (0.5 liters solvent) and bench-scale (~120 liters solvent), showing low reboiler heat duty measured during bench-scale testing, evaluating degradation products, building a rate-based process model, and evaluating the techno-economic performance of the process. The project team (RTI, SINTEF, Linde Engineering) and the technology performed well in each area of advancement. The modifications incorporated throughout the project enabled the attainment of target absorber and regenerator conditions for the process. Reboiler duties below 2,000 kJt/kg CO2 were observed in a bench-scale test unit operated at RTI.

  11. Measurement of underground contamination of non-aqueous phase liquids (NAPLs) on the basis of the radon concentration in ground level air

    International Nuclear Information System (INIS)

    Schubert, M.

    2001-01-01

    It was investigated whether measurements of radon concentrations in ground level air are a suitable method of detecting sub-surface soil contamination with non-aqueous phase liquids (NAPLs). The working postulation was that, due to the very high solubility of radon in NAPLs, and the resulting accumulation of radon in NAPLs, radon exhalation to the ground level air in the proximity of such NAPL contamination should be locally reduced, thus indicating contamination of sub-surface soils with NAPLs. The research work reported was to verify the working theory by way of experiments, and to finally develop a reliable detection method for NAPL contaminations. The investigations comprised theoretical studies, laboratory experiments, experiments in defined soil columns, and extensive field studies [de

  12. Modeling seismic stimulation: Enhanced non-aqueous fluid extraction from saturated porous media under pore-pressure pulsing at low frequencies

    Science.gov (United States)

    Lo, Wei-Cheng; Sposito, Garrison; Huang, Yu-Han

    2012-03-01

    Seismic stimulation, the application of low-frequency stress-pulsing to the boundary of a porous medium containing water and a non-aqueous fluid to enhance the removal of the latter, shows great promise for both contaminated groundwater remediation and enhanced oil recovery, but theory to elucidate the underlying mechanisms lag significantly behind the progress achieved in experimental research. We address this conceptual lacuna by formulating a boundary-value problem to describe pore-pressure pulsing at seismic frequencies that is based on the continuum theory of poroelasticity for an elastic porous medium permeated by two immiscible fluids. An exact analytical solution is presented that is applied numerically using elasticity parameters and hydraulic data relevant to recent proof-of-principle laboratory experiments investigating the stimulation-induced mobilization of trichloroethene (TCE) in water flowing through a compressed sand core. The numerical results indicated that significant stimulation-induced increases of the TCE concentration in effluent can be expected from pore-pressure pulsing in the frequency range of 25-100 Hz, which is in good agreement with what was observed in the laboratory experiments. Sensitivity analysis of our numerical results revealed that the TCE concentration in the effluent increases with the porous medium framework compressibility and the pulsing pressure. Increasing compressibility also leads to an optimal stimulation response at lower frequencies, whereas changing the pulsing pressure does not affect the optimal stimulation frequency. Within the context of our model, the dominant physical cause for enhancement of non-aqueous fluid mobility by seismic stimulation is the dilatory motion of the porous medium in which the solid and fluid phases undergo opposite displacements, resulting in stress-induced changes of the pore volume.

  13. MnO2-x nanosheets on stainless steel felt as a carbon- and binder-free cathode for non-aqueous lithium-oxygen batteries

    Science.gov (United States)

    Wei, Z. H.; Zhao, T. S.; Zhu, X. B.; Tan, P.

    2016-02-01

    Manganese dioxide (MnO2) has been recognized as an effective catalyst for the oxygen reduction and oxygen evolution reactions in non-aqueous lithium-oxygen batteries. However, a further improvement in battery performance with the MnO2 catalyst is limited by its low electronic conductivity and catalytic activity, which strongly depend on the morphology and composition. In this work, we develop a carbon- and binder-free MnO2-x nanosheets/stainless steel (SS) cathode via a simple and effective electrodeposition-solvothermal route. The created Mn(III) and oxygen vacancy in MnO2-x nanosheets allows an significant increase in the electronic conductivity and catalytic activity. It is experimentally shown that the use of the present nanostructure MnO2-x/SS cathode in a non-aqueous lithium-oxygen battery results in a rechargeable specific capacity of 7300 mAh g-1 at a current density of 200 mA g-1, which is 39% higher than that with the MnO2/SS cathode. In addition, the specific capacities at 400 mA g-1 and 800 mA g-1 reach 5249 mAh g-1 and 2813 mAh g-1, respectively, which are over 30% higher than that with the MnO2/SS cathode. Furthermore, the discharge/charge cycle test shows no degradation for 120 cycles. All the results show that the present nanostructure MnO2-x/SS cathode is a promising candidate for high-performance lithium-oxygen batteries.

  14. Mesopore- and Macropore-Dominant Nitrogen-Doped Hierarchically Porous Carbons for High-Energy and Ultrafast Supercapacitors in Non-Aqueous Electrolytes.

    Science.gov (United States)

    Shao, Rong; Niu, Jin; Liang, Jingjing; Liu, Mengyue; Zhang, Zhengping; Dou, Meiling; Huang, Yaqin; Wang, Feng

    2017-12-13

    Non-aqueous electrolytes (e.g., organic and ionic liquid electrolytes) can undergo high working voltage to improve the energy densities of supercapacitors. However, the large ion sizes, high viscosities, and low ionic conductivities of organic and ionic liquid electrolytes tend to cause the low specific capacitances, poor rate, and cycling performance of supercapacitors based on conventional micropore-dominant activated carbon electrodes, limiting their practical applications. Herein, we propose an effective strategy to simultaneously obtain high power and energy densities in non-aqueous electrolytes via using a cattle bone-derived porous carbon as an electrode material. Because of the unique co-activation of KOH and hydroxyapatite (HA) within the cattle bone, nitrogen-doped hierarchically porous carbon (referred to as NHPC-HA/KOH) is obtained and possesses a mesopore- and macropore-dominant porosity with an ultrahigh specific surface area (2203 m 2 g -1 ) of meso- and macropores. The NHPC-HA/KOH electrodes exhibit superior performance with specific capacitances of 224 and 240 F g -1 at 5 A g -1 in 1.0 M TEABF 4 /AN and neat EMIMBF 4 electrolyte, respectively. The symmetric supercapacitor using NHPC-HA/KOH electrodes can deliver integrated high energy and power properties (48.6 W h kg -1 at 3.13 kW kg -1 in 1.0 M TEABF 4 /AN and 75 W h kg -1 at 3.75 kW kg -1 in neat EMIMBF 4 ), as well as superior cycling performance (over 89% of the initial capacitance after 10 000 cycles at 10 A g -1 ).

  15. Binary Masking & Speech Intelligibility

    DEFF Research Database (Denmark)

    Boldt, Jesper

    The purpose of this thesis is to examine how binary masking can be used to increase intelligibility in situations where hearing impaired listeners have difficulties understanding what is being said. The major part of the experiments carried out in this thesis can be categorized as either experime......The purpose of this thesis is to examine how binary masking can be used to increase intelligibility in situations where hearing impaired listeners have difficulties understanding what is being said. The major part of the experiments carried out in this thesis can be categorized as either...... experiments under ideal conditions or as experiments under more realistic conditions useful for real-life applications such as hearing aids. In the experiments under ideal conditions, the previously defined ideal binary mask is evaluated using hearing impaired listeners, and a novel binary mask -- the target...... binary mask -- is introduced. The target binary mask shows the same substantial increase in intelligibility as the ideal binary mask and is proposed as a new reference for binary masking. In the category of real-life applications, two new methods are proposed: a method for estimation of the ideal binary...

  16. Interacting binary stars

    CERN Document Server

    Sahade, Jorge; Ter Haar, D

    1978-01-01

    Interacting Binary Stars deals with the development, ideas, and problems in the study of interacting binary stars. The book consolidates the information that is scattered over many publications and papers and gives an account of important discoveries with relevant historical background. Chapters are devoted to the presentation and discussion of the different facets of the field, such as historical account of the development in the field of study of binary stars; the Roche equipotential surfaces; methods and techniques in space astronomy; and enumeration of binary star systems that are studied

  17. Mining frequent binary expressions

    NARCIS (Netherlands)

    Calders, T.; Paredaens, J.; Kambayashi, Y.; Mohania, M.K.; Tjoa, A.M.

    2000-01-01

    In data mining, searching for frequent patterns is a common basic operation. It forms the basis of many interesting decision support processes. In this paper we present a new type of patterns, binary expressions. Based on the properties of a specified binary test, such as reflexivity, transitivity

  18. Characterization of fatty acid and triacylglycerol composition in animal fats using silver-ion and non-aqueous reversed-phase high-performance liquid chromatography/mass spectrometry and gas chromatography/flame ionization detection

    Czech Academy of Sciences Publication Activity Database

    Lísa, M.; Netušilová, K.; Franěk, L.; Dvořáková, H.; Vrkoslav, Vladimír; Holčapek, M.

    2011-01-01

    Roč. 1218, č. 42 (2011), s. 7499-7510 ISSN 0021-9673 R&D Projects: GA ČR GA203/09/0139 Institutional research plan: CEZ:AV0Z40550506 Keywords : silver-ion HPLC * non-aqueous reversed-phase HPLC * triacylglycerol Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.531, year: 2011

  19. Effects of precursor on the morphology and size of ZrO{sub 2} nanoparticles, synthesized by sol-gel method in non-aqueous medium

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Mohammed Rafiq Hussain; Al-Wassil, Abdulaziz Ibrahim; Mahfouz, Refaat Mohamad [King Saud University, Riyadh (Saudi Arabia). Department of Chemistry, College of Science; Al-Otaibi, Abdullah Mohmmed [King Abdulaziz City for Science and Technology (Saudi Arabia). The NationalProgram for Advanced Materials and Building Systems

    2012-11-15

    Pure zirconium oxide (ZrO{sub 2}) nanoparticles with diameters 10-25 nm were synthesized from ZrOCl{sub 2}.8H{sub 2}O and Zr(SO{sub 4})2.H{sub 2}O with benzyl alcohol as non-aqueous solvent medium using sol-gel method. Sodium lauryl sulfate was added as surfactants to control the particle size. The synthesized ZrO{sub 2} nanoparticles have a mixture of tetragonal and monoclinic structure. The XRD showed the purity of obtained ZrO{sub 2} nanoparticles with tetragonal and monoclinic phase and the crystallite size for ZrOCl{sub 2}.8H{sub 2}O precursor was estimated to be 18.1 nm and that from Zr(SO{sub 4})2.H{sub 2}O was 9.7 nm. The transmission electron microscopy and scanning electron microscopic studies also shows different sizes of nanoparticles and different morphology depending on the precursor used for the synthesis of ZrO{sub 2} nanoparticles. (author)

  20. Effects of precursor on the morphology and size of ZrO2 nanoparticles, synthesized by sol-gel method in non-aqueous medium

    Directory of Open Access Journals (Sweden)

    Mohammed Rafiq Hussain Siddiqui

    2012-12-01

    Full Text Available Pure zirconium oxide (ZrO2 nanoparticles with diameters 10-25 nm were synthesized from ZrOCl2.8H2O and Zr(SO42.H2O with benzyl alcohol as non-aqueous solvent medium using sol-gel method. Sodium lauryl sulfate was added as surfactants to control the particle size. The synthesized ZrO2 nanoparticles have a mixture of tetragonal and monoclinic structure. The XRD showed the purity of obtained ZrO2 nanoparticles with tetragonal and monoclinic phase and the crystallite size for ZrOCl2.8H2O precursor was estimated to be 18.1 nm and that from Zr(SO42.H2O was 9.7 nm. The transmission electron microscopy and scanning electron microscopic studies also shows different sizes of nanoparticles and different morphology depending on the precursor used for the synthesis of ZrO2 nanoparticles

  1. Comparison of a wellpoint vacuum pump system to dual pump recovery system effectiveness for the extraction of light non-aqueous phase liquids

    International Nuclear Information System (INIS)

    Koll, C.S.; Palmerton, D.L. Jr.; Kunzel, R.G.

    1994-01-01

    The effectiveness of two light non-aqueous phase liquid (LNAPL) extraction systems is compared at a site in the Mid-New Jersey Atlantic Coastal Plains Region: an existing dual pump recovery system and a wellpoint vacuum pump system. Home heating oil was released to a shallow sand and gravel aquifer by a leaky underground distribution system in the early 1970s. Eight-inch-diameter dual pump recovery wells were used for the last nine years, to lower the water table and extract LNAPL at several spill sites located throughout a residential community of 1,500 homes. Several small LNAPL plumes still exist today with surface areas ranging from 400 ft 2 to over 28,000 ft 2 . LNAPL recovery peaked in 1985 using dual pump recovery systems, averaging 33 gallons per day (gpd). In 1987, four 24-inch wells were replaced by 11 8-inch-diameter recovery wells at six sites, and LNAPL recovery rates averaged 5 gpd. In recent years, the recovery of LNAPL has declined and when graphed, is asymptotic. In 1993, dual pump recovery of LNAPL averaged 0.3 gpd for all six sites

  2. Adsorption of non-ionic ABC triblock copolymers: Surface modification of TiO2 suspensions in aqueous and non-aqueous medium

    Science.gov (United States)

    Lerch, Jean-Philippe; Atanase, Leonard Ionut; Riess, Gérard

    2017-10-01

    A series of non-ionic ABC triblock copolymers, such as poly(butadiene)-b-poly(2-vinylpyrridine)-b-poly(ethylene oxide) (PB-P2VP-PEO) were synthesized by sequential anionic polymerizations. For these copolymers comprising an organo-soluble PB and a water-soluble PEO block, their P2VP middle block has been selected for its anchoring capacity on solid surfaces. The adsorption isotherms on TiO2 were obtained in heptane and in aqueous medium, as selective solvents. In both of these cases, the P2VP middle block provides the surface anchoring, whereas PB and PEO sequences are acting as stabilizing moieties in heptane and water respectively. By extension to ABC triblock copolymers of the scaling theory developed for diblock copolymers, the density of adsorbed chains could be correlated with the molecular characteristics of the PB-P2VP-PEO triblock copolymers. From a practical point a view, it could be demonstrated that these copolymers are efficient dispersing agents for the TiO2 pigments in both aqueous and non-aqueous medium.

  3. Electrochemical behavior of current collectors for lithium batteries in non-aqueous alkyl carbonate solution and surface analysis by ToF-SIMS

    International Nuclear Information System (INIS)

    Myung, Seung-Taek; Sasaki, Yusuke; Sakurada, Shuhei; Sun, Yang-Kook; Yashiro, Hitoshi

    2009-01-01

    Several metals (Cu, Fe, Al, Ti, and Cr) as current collector for lithium-ion battery were investigated to understand their electrochemical behavior and passivation process in a non-aqueous alkyl carbonate solution containing LiPF 6 salt. From cyclic voltammetric study, it was found that Cu and Fe metals were dissolved into the electrolyte below 4 V vs. Li/Li + . Alternatively, Al and Ti were stable up to 5 V vs. Li/Li + . Their scratched surfaces at 5 V vs. Li/Li + were polarized in a transient mode and it was found that the surfaces were passivated during the polarization test. Formed passive film was composed of two hybrid layers: outer layer by metal (Al and Ti) fluoride and inner by metal oxide, as confirmed by time-of-flight secondary ion mass spectroscopy. Presence of HF in the electrolyte was indispensible to form the metal fluoride layer on the oxide layer. The outer fluoride layer would protect the inner oxide layer and metal substrate from HF attack, bringing about satisfactory corrosion resistance under lithium-ion battery environment.

  4. Electrical conductivity in Li2O2 and its role in determining capacity limitations in non-aqueous Li-O2 batteries.

    Science.gov (United States)

    Viswanathan, V; Thygesen, K S; Hummelshøj, J S; Nørskov, J K; Girishkumar, G; McCloskey, B D; Luntz, A C

    2011-12-07

    Non-aqueous Li-air or Li-O(2) cells show considerable promise as a very high energy density battery couple. Such cells, however, show sudden death at capacities far below their theoretical capacity and this, among other problems, limits their practicality. In this paper, we show that this sudden death arises from limited charge transport through the growing Li(2)O(2) film to the Li(2)O(2)-electrolyte interface, and this limitation defines a critical film thickness, above which it is not possible to support electrochemistry at the Li(2)O(2)-electrolyte interface. We report both electrochemical experiments using a reversible internal redox couple and a first principles metal-insulator-metal charge transport model to probe the electrical conductivity through Li(2)O(2) films produced during Li-O(2) discharge. Both experiment and theory show a "sudden death" in charge transport when film thickness is ~5 to 10 nm. The theoretical model shows that this occurs when the tunneling current through the film can no longer support the electrochemical current. Thus, engineering charge transport through Li(2)O(2) is a serious challenge if Li-O(2) batteries are ever to reach their potential. © 2011 American Institute of Physics

  5. Influence of solvents on species crossover and capacity decay in non-aqueous vanadium redox flow batteries: Characterization of acetonitrile and 1, 3 dioxolane solvent mixture

    Science.gov (United States)

    Bamgbopa, Musbaudeen O.; Almheiri, Saif

    2017-02-01

    The importance of the choice of solvent in a non-aqueous redox flow battery (NARFB) cannot be overemphasized. Several studies demonstrated the influence of the solvent on electrolyte performance in terms of reaction rates, energy/power densities, and efficiencies. In this work, we investigate capacity decay as a direct consequence of varying reactant crossover rates through membranes in different solvent environments. Specifically, we demonstrate the superiority of an 84/16 vol% acetonitrile/1,3 dioxolane solvent mixture over pure acetonitrile in terms of energy efficiency (up to 89%) and capacity retention for vanadium NARFBs - while incorporating a Nafion 115 membrane. The permeability of Nafion to the vanadium acetylacetonate active species is an order of magnitude lower when pure acetonitrile is replaced by the solvent mixture. A method to estimate relative membrane permeability is formulated from numerical analysis of self-discharge experimental data. Furthermore, tests on a modified Nafion/SiO2 membrane, which generally offered low species permeability, also show that different solvents alter membrane permeability. Elemental and morphological analyses of cycled Nafion and NafionSi membranes in different solvent environments indicate that different crossover rates induced by the choice of solvent during cycling are due to changes in the membrane microstructure, intrinsic permeability, swelling rates, and chemical stability.

  6. Cobalt(II) complexes with azole-pyridine type ligands for non-aqueous redox-flow batteries: Tunable electrochemistry via structural modification

    Science.gov (United States)

    Armstrong, Craig G.; Toghill, Kathryn E.

    2017-05-01

    A single species redox flow battery employing a new class of cobalt(II) complexes with 'tunable' tridentate azole-pyridine type ligands is reported. Four structures were synthesised and their electrochemical, physical and battery characteristics were investigated as a function of successive substitution of the ligand terminal pyridyl donors. The Co(II/I) and Co(III/II) couples are stable and quasi-reversible on gold and glassy carbon electrodes, however redox potentials are tunable allowing the cobalt potential difference to be preferentially increased from 1.07 to 1.91 V via pyridine substitution with weaker σ-donating/π-accepting 3,5-dimethylpyrazole groups. The charge-discharge properties of the system were evaluated using an H-type glass cell and graphite rod electrodes. The complexes delivered high Coulombic efficiencies of 89.7-99.8% and very good voltaic efficiencies of 70.3-81.0%. Consequently, energy efficiencies are high at 63.1-80.8%, marking an improvement on other similar non-aqueous systems. Modification of the ligands also improved solubility from 0.18 M to 0.50 M via pyridyl substitution with 3,5-dimethylpyrazole, though the low solubility of the complexes limits the overall energy capacity to between 2.58 and 12.80 W h L-1. Preliminary flow cell studies in a prototype flow cell are also demonstrated.

  7. Highly enhanced electrochemical activity of Ni foam electrodes decorated with nitrogen-doped carbon nanotubes for non-aqueous redox flow batteries

    Science.gov (United States)

    Lee, Jungkuk; Park, Min-Sik; Kim, Ki Jae

    2017-02-01

    Nitrogen-doped carbon nanotubes (NCNTs) are directly grown on the surface of a three-dimensional (3D) Ni foam substrate by floating catalytic chemical vapor deposition (FCCVD). The electrochemical properties of the 3D NCNT-Ni foam are thoroughly examined as a potential electrode for non-aqueous redox flow batteries (RFBs). During synthesis, nitrogen atoms can be successfully doped onto the carbon nanotube (CNT) lattices by forming an abundance of nitrogen-based functional groups. The 3D NCNT-Ni foam electrode exhibits excellent electrochemical activities toward the redox reactions of [Fe (bpy)3]2+/3+ (in anolyte) and [Co(bpy)3]+/2+ (in catholyte), which are mainly attributed to the hierarchical 3D structure of the NCNT-Ni foam electrode and the catalytic effect of nitrogen atoms doped onto the CNTs; this leads to faster mass transfer and charge transfer during operation. As a result, the RFB cell assembled with 3D NCNT-Ni foam electrodes exhibits a high energy efficiency of 80.4% in the first cycle; this performance is maintained up to the 50th cycle without efficiency loss.

  8. Compatibility of a Conventional Non-aqueous Magnesium Electrolyte with a High Voltage V2O5 Cathode and Mg Anode

    Energy Technology Data Exchange (ETDEWEB)

    Sa, Niya [Argonne National Lab. (ANL), Argonne, IL (United States); Proffit, Danielle L. [Argonne National Lab. (ANL), Argonne, IL (United States); Lipson, Albert L. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, Miao [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gautam, Gopalakrishnan Sai [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Hahn, Nathan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Feng, Zhenxing [Argonne National Lab. (ANL), Argonne, IL (United States); Fister, Timothy T. [Argonne National Lab. (ANL), Argonne, IL (United States); Ren, Yang [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Cheng-Jun [Argonne National Lab. (ANL), Argonne, IL (United States); Vaughey, John T. [Argonne National Lab. (ANL), Argonne, IL (United States); Liao, Chen [Argonne National Lab. (ANL), Argonne, IL (United States); Fenter, Paul A. [Argonne National Lab. (ANL), Argonne, IL (United States); Ceder, Gerbrand [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Zavadil, Kevin R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Burrell, Anthony K. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-08-01

    A major roadblock for magnesium ion battery development is the availability of an electrolyte that can deposit Mg reversibly and at the same time is compatible with a high voltage cathode. We report a prospective full magnesium cell utilizing a simple, non-aqueous electrolyte composed of high concentration magnesium bis(trifluoromethane sulfonyl)imide in diglyme, which is compatible with a high voltage vanadium pentoxide (V2O5) cathode and a Mg metal anode. For this system, plating and stripping of Mg metal can be achieved with magnesium bis(trifluoromethane sulfonyl)imide in diglyme electrolyte over a wide concentration range, however, reversible insertion of Mg into V2O5 cathode can only be attained at high electrolyte concentrations. Reversible intercalation of Mg into V2O5 is characterized and confirmed by X-ray diffraction, X-ray absorption near edge spectroscopy and energy dispersive spectroscopy.

  9. Close binary stars

    International Nuclear Information System (INIS)

    Larsson-Leander, G.

    1979-01-01

    Studies of close binary stars are being persued more vigorously than ever, with about 3000 research papers and notes pertaining to the field being published during the triennium 1976-1978. Many major advances and spectacular discoveries were made, mostly due to increased observational efficiency and precision, especially in the X-ray, radio, and ultraviolet domains. Progress reports are presented in the following areas: observational techniques, methods of analyzing light curves, observational data, physical data, structure and models of close binaries, statistical investigations, and origin and evolution of close binaries. Reports from the Coordinates Programs Committee, the Committee for Extra-Terrestrial Observations and the Working Group on RS CVn binaries are included. (Auth./C.F.)

  10. Binary and ternary systems

    International Nuclear Information System (INIS)

    Petrov, D.A.

    1986-01-01

    Conditions for thermodynamical equilibrium in binary and ternary systems are considered. Main types of binary and ternary system phase diagrams are sequently constructed on the basis of general regularities on the character of transition from one equilibria to others. New statements on equilibrium line direction in the diagram triple points and their isothermal cross sections are developed. New represenations on equilibria in case of monovariant curve minimum and maximum on three-phase equilibrium formation in ternary system are introduced

  11. Planet formation in Binaries

    OpenAIRE

    Thebault, Ph.; Haghighipour, N.

    2014-01-01

    Spurred by the discovery of numerous exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation research. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain aspects of the planet formation scenario by submitting them to extreme environments. We review her...

  12. Composition profile determination in isomorphous binary alloys

    International Nuclear Information System (INIS)

    An, C.Y.; Bandeira, I.N.

    1983-07-01

    The inhomogeneity along the growth axis of the pseudo-binary alloys is due to the segregation of the solute which will be mixed in the melt due to convective and diffusive flows. A process for determination of the exact composition profile by measurements of the crystal density, for alloys of the type A sub(1-x) B sub(x), is shown. (Author) [pt

  13. A method for simultaneous analysis of phytosterols and phytosterol esters in tobacco leaves using non aqueous reversed phase chromatography and atmospheric pressure chemical ionization mass spectrometry detector.

    Science.gov (United States)

    Ishida, Naoyuki

    2014-05-02

    While numerous analytical methods for phytosterols have been reported, the similar polarity and large molecules of phytosterol esters have made the methods lengthy and complicated. For this reason, an analytical method that could completely separate phytosterol esters including the higher fatty acids such as palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid in addition to phytosterols without preliminary separation was developed. The separation was accomplished by non-aqueous reversed phase chromatography technique using only acetone and acetonitrile. An atmospheric pressure chemical ionization/mass spectrometry detector configured at selected ion monitoring mode was hyphenated with the separation system to detect phytosterols and phytosterol esters. Twenty-four types of these were consequently separated and then identified with their authentic components. The calibration curve was drawn in the range of about 5 to 25,000 ng/mL with a regression coefficient over 0.999. The limit of detection and limit of quantification, respectively, ranged from 0.9 to 3.0 ng/mL and from 3.0 to 11.0 ng/mL. Recovery rates ranged from 80 to 120%. The quantification results were subjected to statistical analysis and hierarchical clustering analysis, and were used to determine the differences in the amounts of phytosterols and phytosterol esters across tobacco leaves. The newly developed method succeeded in clarifying the whole composition of phytosterols and phytosterol esters in tobacco leaves and in explaining compositional differences across the variety of tobacco leaves. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Determination of Three-Dimensional Morphology and Inner Structure of Second-Phase Inclusions in Metals by Non-Aqueous Solution Electrolytic and Room Temperature Organic Methods

    Directory of Open Access Journals (Sweden)

    Jing Guo

    2018-01-01

    Full Text Available The secondary-phase particles in metals, particularly those composed of non-metallic materials, are often detrimental to the mechanical properties of metals; thus, it is crucial to control inclusion formation and growth. One of the challenges is determining the three-dimensional morphology and inner structures of such inclusions. In this study, a non-aqueous solution electrolytic method and a room-temperature organic technique were developed based on the principle of electrochemistry to determine the three-dimensional morphologies and inner structures of non-metallic inclusions in Al-killed steel, Si-killed steel, and ductile cast iron. The inclusions were first extracted without any damage to the inclusions, and then the collected inclusions were wrapped and cut through Cu ion deposition. The results revealed that the inclusions in Al-killed steel had an irregular morphology, that those in the Si-killed steel were mainly spherical, and that almost all the spheroidal graphite in the ductile cast iron featured a uniform globular morphology. In addition, nucleation was not observed in the inner structures of the inclusions in the Al-killed steel, while some dendritic or rod-like MnS phase precipitates appeared on the silicate inclusion surfaces, and some silicate-rich phases were detected in their inner matrix. For spheroidal graphite, rare-earth oxides (one particle or more were observed as nuclei in the center of almost every graphite particle. The formation and evolution of inclusions in these types of metals can be better understood by means of the two developed methods.

  15. Skewed Binary Search Trees

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Moruz, Gabriel

    2006-01-01

    It is well-known that to minimize the number of comparisons a binary search tree should be perfectly balanced. Previous work has shown that a dominating factor over the running time for a search is the number of cache faults performed, and that an appropriate memory layout of a binary search tree...... can reduce the number of cache faults by several hundred percent. Motivated by the fact that during a search branching to the left or right at a node does not necessarily have the same cost, e.g. because of branch prediction schemes, we in this paper study the class of skewed binary search trees....... For all nodes in a skewed binary search tree the ratio between the size of the left subtree and the size of the tree is a fixed constant (a ratio of 1/2 gives perfect balanced trees). In this paper we present an experimental study of various memory layouts of static skewed binary search trees, where each...

  16. Modelling binary data

    CERN Document Server

    Collett, David

    2002-01-01

    INTRODUCTION Some Examples The Scope of this Book Use of Statistical Software STATISTICAL INFERENCE FOR BINARY DATA The Binomial Distribution Inference about the Success Probability Comparison of Two Proportions Comparison of Two or More Proportions MODELS FOR BINARY AND BINOMIAL DATA Statistical Modelling Linear Models Methods of Estimation Fitting Linear Models to Binomial Data Models for Binomial Response Data The Linear Logistic Model Fitting the Linear Logistic Model to Binomial Data Goodness of Fit of a Linear Logistic Model Comparing Linear Logistic Models Linear Trend in Proportions Comparing Stimulus-Response Relationships Non-Convergence and Overfitting Some other Goodness of Fit Statistics Strategy for Model Selection Predicting a Binary Response Probability BIOASSAY AND SOME OTHER APPLICATIONS The Tolerance Distribution Estimating an Effective Dose Relative Potency Natural Response Non-Linear Logistic Regression Models Applications of the Complementary Log-Log Model MODEL CHECKING Definition of Re...

  17. Evolution of dwarf binaries

    International Nuclear Information System (INIS)

    Tutukov, A.V.; Fedorova, A.V.; Yungel'son, L.R.

    1982-01-01

    The conditions of mass exchange in close binary systems with masses of components less or equal to one solar mass have been analysed for the case, when the system radiates gravitational waves. It has been shown that the mass exchange rate depends in a certain way on the mass ratio of components and on the mass of component that fills its inner critical lobe. The comparison of observed periods, masses of contact components, and mass exchange rates of observed cataclysmic binaries have led to the conclusion that the evolution of close binaries WZ Sge, OY Car, Z Cha, TT Ari, 2A 0311-227, and G 61-29 may be driven by the emission of gravitational waves [ru

  18. Binary catalogue of exoplanets

    Science.gov (United States)

    Schwarz, Richard; Bazso, Akos; Zechner, Renate; Funk, Barbara

    2016-02-01

    Since 1995 there is a database which list most of the known exoplanets (The Extrasolar Planets Encyclopaedia at http://exoplanet.eu/). With the growing number of detected exoplanets in binary and multiple star systems it became more important to mark and to separate them into a new database, which is not available in the Extrasolar Planets Encyclopaedia. Therefore we established an online database (which can be found at: http://www.univie.ac.at/adg/schwarz/multiple.html) for all known exoplanets in binary star systems and in addition for multiple star systems, which will be updated regularly and linked to the Extrasolar Planets Encyclopaedia. The binary catalogue of exoplanets is available online as data file and can be used for statistical purposes. Our database is divided into two parts: the data of the stars and the planets, given in a separate list. We describe also the different parameters of the exoplanetary systems and present some applications.

  19. Binary and Millisecond Pulsars.

    Science.gov (United States)

    Lorimer, Duncan R

    2008-01-01

    We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1800. There are now 83 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 140 pulsars in 26 of the Galactic globular clusters. Recent highlights include the discovery of the young relativistic binary system PSR J1906+0746, a rejuvination in globular cluster pulsar research including growing numbers of pulsars with masses in excess of 1.5 M ⊙ , a precise measurement of relativistic spin precession in the double pulsar system and a Galactic millisecond pulsar in an eccentric ( e = 0.44) orbit around an unevolved companion. Supplementary material is available for this article at 10.12942/lrr-2008-8.

  20. Binary and Millisecond Pulsars

    Directory of Open Access Journals (Sweden)

    Lorimer Duncan R.

    2008-11-01

    Full Text Available We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1800. There are now 83 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 140 pulsars in 26 of the Galactic globular clusters. Recent highlights include the discovery of the young relativistic binary system PSR J1906+0746, a rejuvination in globular cluster pulsar research including growing numbers of pulsars with masses in excess of 1.5M_⊙, a precise measurement of relativistic spin precession in the double pulsar system and a Galactic millisecond pulsar in an eccentric (e = 0.44 orbit around an unevolved companion.

  1. Dissipative binary collisions

    International Nuclear Information System (INIS)

    Aboufirassi, M; Angelique, J.C.; Bizard, G.; Bougault, R.; Brou, R.; Buta, A.; Colin, J.; Cussol, D.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Kerambrun, A.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lefebvres, F.; Lopez, O.; Louvel, M.; Meslin, C.; Metivier, V.; Nakagawa, T.; Peter, J.; Popescu, R.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Wieloch, A.; Yuasa-Nakagawa, K.

    1998-01-01

    The binary character of the heavy ion collisions at intermediate energies in the exit channel has been observed under 30 MeV/n in medium and heavy systems. Measurements in light systems at energies approaching ∼ 100 MeV/nucleon as well as in very heavy systems have allowed to extend considerably the investigations of this binary process. Thus, the study of the Pb + Au system showed that the complete charge events indicated two distinct sources: the quasi-projectile and the quasi-target. The characteristics of these two sources are rather well reproduced by a trajectory computation which takes into account the Coulomb and nuclear forces and the friction appearing from the projectile-target interaction. The Wilczynski diagram is used to probe the correlation between the kinetic energy quenching and the deflecting angle. In case of the system Pb + Au at 29 MeV/nucleon the diagram indicate dissipative binary collisions typical for low energies. This binary aspect was also detected in the systems Xe + Ag at 44 MeV/nucleon, 36 Ar + 27 Al and 64 Zn + nat Ti. Thus, it was possible to reconstruct the quasi-projectile and to study its mass and excitation energy evolution as a function of the impact parameter. The dissipative binary collisions represent for the systems and energies under considerations the main contribution to the cross section. This does not implies that there are not other processes; particularly, the more or less complete fusion is also observed but with a low cross section which decreases with the increase of bombardment energy. More exclusive measurements with the INDRA detector on quasi-symmetric systems as Ar + KCl and Xe + Sn seem to confirm the importance of the binary collisions. The two source reconstruction of the Xe + Sn data at 50 MeV/nucleon reproduces the same behaviour as that observed in the system Pb + Au at 29 MeV/nucleon

  2. Binary and Millisecond Pulsars

    Directory of Open Access Journals (Sweden)

    Lorimer Duncan R.

    2005-11-01

    Full Text Available We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1700. There are now 80 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 103 pulsars in 24 of the Galactic globular clusters. Recent highlights have been the discovery of the first ever double pulsar system and a recent flurry of discoveries in globular clusters, in particular Terzan 5.

  3. Equational binary decision diagrams

    NARCIS (Netherlands)

    J.F. Groote (Jan Friso); J.C. van de Pol (Jaco)

    2000-01-01

    textabstractWe incorporate equations in binary decision diagrams (BDD). The resulting objects are called EQ-BDDs. A straightforward notion of ordered EQ-BDDs (EQ-OBDD) is defined, and it is proved that each EQ-BDD is logically equivalent to an EQ-OBDD. Moreover, on EQ-OBDDs satisfiability and

  4. Binary tense and modality

    NARCIS (Netherlands)

    Broekhuis, H.; Verkuyl, H.J

    2014-01-01

    The present paper adopts as its point of departure the claim by Te Winkel (1866) and Verkuyl (2008) that mental temporal representations are built on the basis of three binary oppositions: Present/Past, Synchronous/Posterior and Imperfect/Perfect. Te Winkel took the second opposition in terms of the

  5. N-Bit Binary Resistor

    Science.gov (United States)

    Tcheng, Ping

    1989-01-01

    Binary resistors in series tailored to precise value of resistance. Desired value of resistance obtained by cutting appropriate traces across resistors. Multibit, binary-based, adjustable resistor with high resolution used in many applications where precise resistance required.

  6. The True Ultracool Binary Fraction Using Spectral Binaries

    Science.gov (United States)

    Bardalez Gagliuffi, Daniella; Burgasser, Adam J.; Schmidt, Sarah J.; Gagné, Jonathan; Faherty, Jacqueline K.; Cruz, Kelle; Gelino, Chris

    2018-01-01

    Brown dwarfs bridge the gap between stars and giant planets. While the essential mechanisms governing their formation are not well constrained, binary statistics are a direct outcome of the formation process, and thus provide a means to test formation theories. Observational constraints on the brown dwarf binary fraction place it at 10 ‑ 20%, dominated by imaging studies (85% of systems) with the most common separation at 4 AU. This coincides with the resolution limit of state-of-the-art imaging techniques, suggesting that the binary fraction is underestimated. We have developed a separation-independent method to identify and characterize tightly-separated (dwarfs as spectral binaries by identifying traces of methane in the spectra of late-M and early-L dwarfs. Imaging follow-up of 17 spectral binaries yielded 3 (18%) resolved systems, corroborating the observed binary fraction, but 5 (29%) known binaries were missed, reinforcing the hypothesis that the short-separation systems are undercounted. In order to find the true binary fraction of brown dwarfs, we have compiled a volume-limited, spectroscopic sample of M7-L5 dwarfs and searched for T dwarf companions. In the 25 pc volume, 4 candidates were found, three of which are already confirmed, leading to a spectral binary fraction of 0.95 ± 0.50%, albeit for a specific combination of spectral types. To extract the true binary fraction and determine the biases of the spectral binary method, we have produced a binary population simulation based on different assumptions of the mass function, age distribution, evolutionary models and mass ratio distribution. Applying the correction fraction resulting from this method to the observed spectral binary fraction yields a true binary fraction of 27 ± 4%, which is roughly within 1σ of the binary fraction obtained from high resolution imaging studies, radial velocity and astrometric monitoring. This method can be extended to identify giant planet companions to young brown

  7. Black holes in binary stars

    NARCIS (Netherlands)

    Wijers, R.A.M.J.

    1996-01-01

    Introduction Distinguishing neutron stars and black holes Optical companions and dynamical masses X-ray signatures of the nature of a compact object Structure and evolution of black-hole binaries High-mass black-hole binaries Low-mass black-hole binaries Low-mass black holes Formation of black holes

  8. Learning to assign binary weights to binary descriptor

    Science.gov (United States)

    Huang, Zhoudi; Wei, Zhenzhong; Zhang, Guangjun

    2016-10-01

    Constructing robust binary local feature descriptors are receiving increasing interest due to their binary nature, which can enable fast processing while requiring significantly less memory than their floating-point competitors. To bridge the performance gap between the binary and floating-point descriptors without increasing the computational cost of computing and matching, optimal binary weights are learning to assign to binary descriptor for considering each bit might contribute differently to the distinctiveness and robustness. Technically, a large-scale regularized optimization method is applied to learn float weights for each bit of the binary descriptor. Furthermore, binary approximation for the float weights is performed by utilizing an efficient alternatively greedy strategy, which can significantly improve the discriminative power while preserve fast matching advantage. Extensive experimental results on two challenging datasets (Brown dataset and Oxford dataset) demonstrate the effectiveness and efficiency of the proposed method.

  9. Processing Of Binary Images

    Science.gov (United States)

    Hou, H. S.

    1985-07-01

    An overview of the recent progress in the area of digital processing of binary images in the context of document processing is presented here. The topics covered include input scan, adaptive thresholding, halftoning, scaling and resolution conversion, data compression, character recognition, electronic mail, digital typography, and output scan. Emphasis has been placed on illustrating the basic principles rather than descriptions of a particular system. Recent technology advances and research in this field are also mentioned.

  10. Marginal and Random Intercepts Models for Longitudinal Binary Data with Examples from Criminology

    Science.gov (United States)

    Long, Jeffrey D.; Loeber, Rolf; Farrington, David P.

    2009-01-01

    Two models for the analysis of longitudinal binary data are discussed: the marginal model and the random intercepts model. In contrast to the linear mixed model (LMM), the two models for binary data are not subsumed under a single hierarchical model. The marginal model provides group-level information whereas the random intercepts model provides…

  11. [Analysis of binary classification repeated measurement data with GEE and GLMMs using SPSS software].

    Science.gov (United States)

    An, Shengli; Zhang, Yanhong; Chen, Zheng

    2012-12-01

    To analyze binary classification repeated measurement data with generalized estimating equations (GEE) and generalized linear mixed models (GLMMs) using SPSS19.0. GEE and GLMMs models were tested using binary classification repeated measurement data sample using SPSS19.0. Compared with SAS, SPSS19.0 allowed convenient analysis of categorical repeated measurement data using GEE and GLMMs.

  12. Robust Bayes Forecasting For Grouped Binary Data With Known Distortion Interval

    OpenAIRE

    Pashkevich, M.

    2004-01-01

    The paper is devoted the problem of robust forecasting for the beta-mixed hierarchical models of grouped binary data in the case of stochastic additive distortions of binary observations. In the case of known lower and upper bounds of the distortion intervals, a new robust minimax Bayes predictor is developed. The performance of the proposed forecasting technique is validated by computer simulationtadata.

  13. A new approach of the understanding of sulfur dioxide reduction in non-aqueous solvent; Une nouvelle approche de la comprehension de la reduction du dioxyde de soufre en solvant non aqueux

    Energy Technology Data Exchange (ETDEWEB)

    Potteau, E.; Levillain, E.; Lelieur, J.P. [Laboratoire de Spectrochimie Infrarouge et Raman (LASIR, UPR 2631 CNRS) Haute Etudes Industrielles (HEI), 59 - Lille (France)

    1996-12-31

    The study of SO{sub 2} reduction in non-aqueous solvent can help to understand the functioning of Li/SO{sub 2} batteries and to find a simpler way for the synthesis of Li{sub 2}S{sub 2}O{sub 4} dithionite. This paper presents the results of electrochemical studies (cycle volt-amperometry in semi-infinite and thin film diffusion conditions, visible spectro-electrochemistry) and spectroscopic studies (UV, visible and RPE) performed on SO{sub 2} solutions. A mechanism of SO{sub 2} reduction is proposed and discussed. (J.S.) 18 refs.

  14. A new approach of the understanding of sulfur dioxide reduction in non-aqueous solvent; Une nouvelle approche de la comprehension de la reduction du dioxyde de soufre en solvant non aqueux

    Energy Technology Data Exchange (ETDEWEB)

    Potteau, E; Levillain, E; Lelieur, J P [Laboratoire de Spectrochimie Infrarouge et Raman (LASIR, UPR 2631 CNRS) Haute Etudes Industrielles (HEI), 59 - Lille (France)

    1997-12-31

    The study of SO{sub 2} reduction in non-aqueous solvent can help to understand the functioning of Li/SO{sub 2} batteries and to find a simpler way for the synthesis of Li{sub 2}S{sub 2}O{sub 4} dithionite. This paper presents the results of electrochemical studies (cycle volt-amperometry in semi-infinite and thin film diffusion conditions, visible spectro-electrochemistry) and spectroscopic studies (UV, visible and RPE) performed on SO{sub 2} solutions. A mechanism of SO{sub 2} reduction is proposed and discussed. (J.S.) 18 refs.

  15. Massive Black Hole Binary Evolution

    Directory of Open Access Journals (Sweden)

    Merritt David

    2005-11-01

    Full Text Available Coalescence of binary supermassive black holes (SBHs would constitute the strongest sources of gravitational waves to be observed by LISA. While the formation of binary SBHs during galaxy mergers is almost inevitable, coalescence requires that the separation between binary components first drop by a few orders of magnitude, due presumably to interaction of the binary with stars and gas in a galactic nucleus. This article reviews the observational evidence for binary SBHs and discusses how they would evolve. No completely convincing case of a bound, binary SBH has yet been found, although a handful of systems (e.g. interacting galaxies; remnants of galaxy mergers are now believed to contain two SBHs at projected separations of <~ 1kpc. N-body studies of binary evolution in gas-free galaxies have reached large enough particle numbers to reproduce the slow, “diffusive” refilling of the binary’s loss cone that is believed to characterize binary evolution in real galactic nuclei. While some of the results of these simulations - e.g. the binary hardening rate and eccentricity evolution - are strongly N-dependent, others - e.g. the “damage” inflicted by the binary on the nucleus - are not. Luminous early-type galaxies often exhibit depleted cores with masses of ~ 1-2 times the mass of their nuclear SBHs, consistent with the predictions of the binary model. Studies of the interaction of massive binaries with gas are still in their infancy, although much progress is expected in the near future. Binary coalescence has a large influence on the spins of SBHs, even for mass ratios as extreme as 10:1, and evidence of spin-flips may have been observed.

  16. Binary optics: Trends and limitations

    Science.gov (United States)

    Farn, Michael W.; Veldkamp, Wilfrid B.

    1993-01-01

    We describe the current state of binary optics, addressing both the technology and the industry (i.e., marketplace). With respect to the technology, the two dominant aspects are optical design methods and fabrication capabilities, with the optical design problem being limited by human innovation in the search for new applications and the fabrication issue being limited by the availability of resources required to improve fabrication capabilities. With respect to the industry, the current marketplace does not favor binary optics as a separate product line and so we expect that companies whose primary purpose is the production of binary optics will not represent the bulk of binary optics production. Rather, binary optics' more natural role is as an enabling technology - a technology which will directly result in a competitive advantage in a company's other business areas - and so we expect that the majority of binary optics will be produced for internal use.

  17. Particle acceleration in binaries

    Directory of Open Access Journals (Sweden)

    Sinitsyna V.G.

    2017-01-01

    Full Text Available Cygnus X-3 massive binary system is one of the powerful sources of radio and X-ray emission consisting of an accreting compact object, probably a black hole, with a Wolf-Rayet star companion. Based on the detections of ultra high energy gamma-rays by Kiel and Havera Park, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of long-term observations of the Cyg X-3 binary at energies 800 GeV–85 TeV detected by SHALON in 1995 are presented with images, integral spectra and spectral energy distribution. The identification of source with Cygnus X-3 detected by SHALON was secured by the detection of its 4.8 hour orbital period in TeV gamma-rays. During the whole observation period of Cyg X-3 with SHALON significant flux increases were detected at energies above 0.8 TeV. These TeV flux increases are correlated with flaring activity at a lower energy range of X-ray and/or at observations of Fermi LAT as well as with radio emission from the relativistic jets of Cygnus X-3. The variability of very high-energy gamma-radiation and correlation of radiation activity in the wide energy range can provide essential information on particle mechanism production up to very high energies. Whereas, modulation of very high energy emission connected to the orbital motion of the binary system, provides an understanding of the emission processes, nature and location of particle acceleration.

  18. Magnetic binary nanofillers

    International Nuclear Information System (INIS)

    Morales Mendoza, N.; Goyanes, S.; Chiliotte, C.; Bekeris, V.; Rubiolo, G.; Candal, R.

    2012-01-01

    Magnetic binary nanofillers containing multiwall carbon nanotubes (MWCNT) and hercynite were synthesized by Chemical Vapor Deposition (CVD) on Fe/AlOOH prepared by the sol-gel method. The catalyst precursor was fired at 450 °C, ground and sifted through different meshes. Two powders were obtained with different particle sizes: sample A (50-75 μm) and sample B (smaller than 50 μm). These powders are composed of iron oxide particles widely dispersed in the non-crystalline matrix of aluminum oxide and they are not ferromagnetic. After reduction process the powders are composed of α-Fe nanoparticles inside hercynite matrix. These nanofillers are composed of hercynite containing α-Fe nanoparticles and MWCNT. The binary magnetic nanofillers were slightly ferromagnetic. The saturation magnetization of the nanofillers depended on the powder particle size. The nanofiller obtained from powder particles in the range 50-75 μm showed a saturation magnetization 36% higher than the one formed from powder particles smaller than 50 μm. The phenomenon is explained in terms of changes in the magnetic environment of the particles as consequence of the presence of MWCNT.

  19. Magnetic binary nanofillers

    Energy Technology Data Exchange (ETDEWEB)

    Morales Mendoza, N. [INQUIMAE, CONICET-UBA, Ciudad Universitaria, Pab2, (C1428EHA) Bs As (Argentina); LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Goyanes, S. [LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Chiliotte, C.; Bekeris, V. [LBT, Dep. De Fisica, FCEN-UBA. Ciudad Universitaria, Pab1, C1428EGA CABA (Argentina); Rubiolo, G. [LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Unidad de Actividad Materiales, CNEA, Av Gral. Paz 1499, San Martin (1650), Prov. de Bs As (Argentina); Candal, R., E-mail: candal@qi.fcen.uba.ar [INQUIMAE, CONICET-UBA, Ciudad Universitaria, Pab2, (C1428EHA) Bs As (Argentina); Escuela de Ciencia y Tecnologia, 3iA, Universidad de Gral. San Martin, San Martin, Prov. Bs As (Argentina)

    2012-08-15

    Magnetic binary nanofillers containing multiwall carbon nanotubes (MWCNT) and hercynite were synthesized by Chemical Vapor Deposition (CVD) on Fe/AlOOH prepared by the sol-gel method. The catalyst precursor was fired at 450 Degree-Sign C, ground and sifted through different meshes. Two powders were obtained with different particle sizes: sample A (50-75 {mu}m) and sample B (smaller than 50 {mu}m). These powders are composed of iron oxide particles widely dispersed in the non-crystalline matrix of aluminum oxide and they are not ferromagnetic. After reduction process the powders are composed of {alpha}-Fe nanoparticles inside hercynite matrix. These nanofillers are composed of hercynite containing {alpha}-Fe nanoparticles and MWCNT. The binary magnetic nanofillers were slightly ferromagnetic. The saturation magnetization of the nanofillers depended on the powder particle size. The nanofiller obtained from powder particles in the range 50-75 {mu}m showed a saturation magnetization 36% higher than the one formed from powder particles smaller than 50 {mu}m. The phenomenon is explained in terms of changes in the magnetic environment of the particles as consequence of the presence of MWCNT.

  20. EXIT Chart Analysis of Binary Message-Passing Decoders

    DEFF Research Database (Denmark)

    Lechner, Gottfried; Pedersen, Troels; Kramer, Gerhard

    2007-01-01

    Binary message-passing decoders for LDPC codes are analyzed using EXIT charts. For the analysis, the variable node decoder performs all computations in the L-value domain. For the special case of a hard decision channel, this leads to the well know Gallager B algorithm, while the analysis can...... be extended to channels with larger output alphabets. By increasing the output alphabet from hard decisions to four symbols, a gain of more than 1.0 dB is achieved using optimized codes. For this code optimization, the mixing property of EXIT functions has to be modified to the case of binary message......-passing decoders....

  1. Relativistic Binaries in Globular Clusters

    Directory of Open Access Journals (Sweden)

    Matthew J. Benacquista

    2013-03-01

    Full Text Available Galactic globular clusters are old, dense star systems typically containing 10^4 – 10^6 stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution that leads to relativistic binaries, and current and possible future observational evidence for this population. Our discussion of globular cluster evolution will focus on the processes that boost the production of tight binary systems and the subsequent interaction of these binaries that can alter the properties of both bodies and can lead to exotic objects. Direct N-body integrations and Fokker–Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.

  2. Spectral properties of binary asteroids

    Science.gov (United States)

    Pajuelo, Myriam; Birlan, Mirel; Carry, Benoît; DeMeo, Francesca E.; Binzel, Richard P.; Berthier, Jérôme

    2018-04-01

    We present the first attempt to characterize the distribution of taxonomic class among the population of binary asteroids (15% of all small asteroids). For that, an analysis of 0.8-2.5{μ m} near-infrared spectra obtained with the SpeX instrument on the NASA/IRTF is presented. Taxonomic class and meteorite analog is determined for each target, increasing the sample of binary asteroids with known taxonomy by 21%. Most binary systems are bound in the S-, X-, and C- classes, followed by Q and V-types. The rate of binary systems in each taxonomic class agrees within uncertainty with the background population of small near-Earth objects and inner main belt asteroids, but for the C-types which are under-represented among binaries.

  3. Planets in Binary Star Systems

    CERN Document Server

    Haghighipour, Nader

    2010-01-01

    The discovery of extrasolar planets over the past decade has had major impacts on our understanding of the formation and dynamical evolution of planetary systems. There are features and characteristics unseen in our solar system and unexplainable by the current theories of planet formation and dynamics. Among these new surprises is the discovery of planets in binary and multiple-star systems. The discovery of such "binary-planetary" systems has confronted astrodynamicists with many new challenges, and has led them to re-examine the theories of planet formation and dynamics. Among these challenges are: How are planets formed in binary star systems? What would be the notion of habitability in such systems? Under what conditions can binary star systems have habitable planets? How will volatiles necessary for life appear on such planets? This volume seeks to gather the current research in the area of planets in binary and multistar systems and to familiarize readers with its associated theoretical and observation...

  4. RS CVn binary systems

    International Nuclear Information System (INIS)

    Linsky, J.L.

    1984-01-01

    The author attempts to place in context the vast amount of data obtained in the last few years as a result of X-ray, ultraviolet, optical, and microwave observations of RS CVn and similar spectroscopic binary systems. He concentrates on the RS CVn systems and their long-period analogs, and restricts the scope by attempting to answer on the basis of the recent data and theory following questions: (1) Are the original defining characteristics still valid and still adequate? (2) What is the evidence for discrete active regions? (3) Have we derived any meaningful physical properties for the atmospheres of RS CVn systems? (4) What are the flare observations telling us about magnetic fields in the RS CVn systems? (5) Is there evidence for systematic trends in RS CVn systems with spectral type?

  5. Open Circuit Potential Changes upon Protonation/Deprotonation of ω-Functionalized Alkanethiols on Au: Determination of Surface pK {sub 1/2} in Aqueous and Non-Aqueous System

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seung Ryul; Park, Kyung Soon; Jang, Jae Won; Hwang, Seong Pil [Korea Univ., Sejong (Korea, Republic of)

    2016-09-15

    The controlled assembly of functional nanomaterials has been drawing significant interest for making devices by integration of nanomaterials. The building blocks of functional nanomaterials might be confined spatially on the chemically patterned surface through both covalent and non-covalent bonds. Potentiometric measurement is affordable technique for various researchers because it requires only voltmeter and reference electrode. Moreover, it can be applied to various polar solvent such as methanol and ethanol. The open circuit potential (OCP) is measured indicating the potential difference between reference electrode and working electrode. The potential of working electrode might be affected by redox chemical reaction and charge state/separation. Our results provide the simple and affordable method to investigate pK {sub 1/2} of thin film both in aqueous phase and in non-aqueous phase, which has significant role in colloidal chemistry, nanochemistry, surface chemistry, electrochemistry, and others.

  6. Increasing the energy density of the non-aqueous vanadium redox flow battery with new electrolytes; Neue Elektrolyte zur Steigerung der Energiedichte einer nicht-waessrigen Vanadium-Acetylacetonat-Redox-Flow-Batterie

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Tatjana

    2015-07-01

    Redox flow battery (RFB) is a promising energy storage technology which is similar to a polymer electrolyte membrane fuel cell. Currently, this electrochemical energy conversion device is used as a storage system for renewable energies or as uninterruptable power source. All-Vanadium-RFB (VRFB) and Zinc-Bromine-RFB are most well-known types of the aqueous RFB for these applications. But also the non-aqueous RFB is becoming more and more famous, because non-aqueous electrolytes offer wider operating temperature ranges, wider stable potential windows and a potentially higher energy density. However, current research studies show that the solubility of the most used redox active species is not sufficient. Therefore, present study aims to show concepts in order to solve this problem. Vanadium(III)acetylacetonate (V(acac){sub 3}) is used as active species, supported by tetrabutylammonium hexafluorophosphate. In acetonitrile it shows two quasi-reversible redox couples and a cell potential ∝2.2 V. The maximum solubility is ∝0.6 M. In this work other solvents and solvent mixtures were examined with the objective of increasing the solubility of V(acac){sub 3}. In 1,3-dioxolane the solubility was e.g. 0.8 M, dimethyl sulfoxide showed good battery performance with the highest energy efficiency ∝44 %. Acetylacetone is able to regenerate V(acac){sub 3} from the side product that is formed by reaction with water. The new electrolyte solution consisting of acetonitrile, 1,3-dioxolane and dimethyl sulfoxide nearly doubled the solubility of V(acac){sub 3}. In galvanostatic charge-discharge tests, single cell V(acac){sub 3} RFB exhibited energy efficiency between 25-50 % depending an test conditions. Also, the influence of water and oxygen addition an electrolyte was investigated. Finally, experiments with different ambient temperatures show that V(acac){sub 3} RFB is able to operate at temperatures such as 0 C and -25 C.

  7. A rationally designed self-standing V2O5 electrode for high voltage non-aqueous all-solid-state symmetric (2.0 V) and asymmetric (2.8 V) supercapacitors.

    Science.gov (United States)

    Ghosh, Meena; Vijayakumar, Vidyanand; Soni, Roby; Kurungot, Sreekumar

    2018-05-10

    The maximum capacitive potential window of certain pseudocapacitive materials cannot be accessed in aqueous electrolytes owing to the low dissociation potential of 1.2 V possessed by water molecules. However, the inferior pseudocapacitance exhibited by the commonly used electrode materials when integrated with non-aqueous electrolytes still remains a challenge in the development of supercapacitors (SC). Proper selection of materials for the electrode and a rational design process are indeed important to overcome these practical intricacies so that such systems can perform well with non-aqueous electrolytes. We address this challenge by fabricating a prototype all-solid-state device designed with high-capacitive V2O5 as the electrode material along with a Li-ion conducting organic electrolyte. V2O5 is synthesized on a pre-treated carbon-fibre paper by adopting an electrochemical deposition technique that effects an improved contact resistance. A judicious electrode preparation strategy makes it possible to overcome the constraints of the low ionic and electrical conductivities imposed by the electrolyte and electrode material, respectively. The device, assembled in a symmetrical fashion, achieves a high specific capacitance of 406 F g-1 (at 1 A g-1). The profitable aspect of using an organic electrolyte is also demonstrated with an asymmetric configuration by using activated carbon as the positive and V2O5 as the negative electrode materials, respectively. The asymmetric device displays a wide working-voltage window of 2.8 V and delivers a high energy density of 102.68 W h kg-1 at a power density of 1.49 kW kg-1. Moreover, the low equivalent series resistance of 9.9 Ω and negligible charge transfer resistance are observed in the impedance spectra, which is a key factor that accounts for such an exemplary performance.

  8. Non-aqueous electrolytes for isotachophoresis of weak bases and its application to the comprehensive preconcentration of the 20 proteinogenic amino acids in column-coupling ITP/CE-MS.

    Science.gov (United States)

    Kler, Pablo A; Huhn, Carolin

    2014-11-01

    Isotachophoresis (ITP) has long been used alone but also as a preconcentration technique for capillary electrophoresis (CE). Unfortunately, up to now, its application is restricted to relatively strong acids and bases as either the degree of (de)protonation is too low or the water dissociation is too high, evoking zone electrophoresis. With the comprehensive ITP analysis of all 20 proteinogenic amino acids as model analytes, we, here, show that non-aqueous ITP using dimethylsulfoxide as a solvent solves this ITP shortcoming. Dimethylsulfoxide changes the pH regime of analytes and electrolytes but, more importantly, strongly reduces the proton mobility by prohibiting hydrogen bonds and thus, the so-called Zundel-Eigen-Zundel electrical conduction mechanism of flipping hydrogen bonds. The effects are demonstrated in an electrolyte system with taurine or H(+) as terminator, and imidazole as leader together with strong acids such as oxalic and even trifluoroacetic acid as counterions, both impossible to use in aqueous solution. Mass spectrometric as well as capacitively coupled contactless conductivity detection (C(4)D) are used to follow the ITP processes. To demonstrate the preconcentration capabilities of ITP in a two-dimensional set-up, we, here, also demonstrate that our non-aqueous ITP method can be combined with capillary electrophoresis-mass spectrometry in a column-coupling system using a hybrid approach of capillaries coupled to a microfluidic interface. For this, C(4)D was optimized for on-chip detection with the electrodes aligned on top of a thin glass lid of the microfluidic chip.

  9. Optimally cloned binary coherent states

    Science.gov (United States)

    Müller, C. R.; Leuchs, G.; Marquardt, Ch.; Andersen, U. L.

    2017-10-01

    Binary coherent state alphabets can be represented in a two-dimensional Hilbert space. We capitalize this formal connection between the otherwise distinct domains of qubits and continuous variable states to map binary phase-shift keyed coherent states onto the Bloch sphere and to derive their quantum-optimal clones. We analyze the Wigner function and the cumulants of the clones, and we conclude that optimal cloning of binary coherent states requires a nonlinearity above second order. We propose several practical and near-optimal cloning schemes and compare their cloning fidelity to the optimal cloner.

  10. Micellar solubilization in strongly interacting binary surfactant systems. [Binary surfactant systems of: dodecyltrimethylammonium chloride + sodium dodecyl sulfate; benzyldimethyltetradecylammonium chloride + tetradecyltrimethylammonium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Treiner, C. (Universite Pierre et Marie Curie, Paris (France)); Nortz, M.; Vaution, C. (Faculte de Pharmacie de Paris-sud, Chatenay-Malabry (France))

    1990-07-01

    The apparent partition coefficient P of barbituric acids between micelles and water has been determined in mixed binary surfactant solutions from solubility measurements in the whole micellar composition range. The binary systems chosen ranged from the strongly interacting system dodecyltrimethylammonium chloride + sodium dodecyl sulfate to weakly interacting systems such as benzyldimethyltetradecylammonium chloride + tetradecyltrimethyammonium chloride. In all cases studied, mixed micelle formation is unfavorable to micellar solubilization. A correlation is found between the unlike surfactants interaction energy, as measured by the regular solution parameter {beta} and the solute partition coefficient change upon surfactant mixing. By use of literature data on micellar solubilization in binary surfactant solutions, it is shown that the change of P for solutes which are solubilized by surface adsorption is generally governed by the sign and amplitude of the interaction parameter {beta}.

  11. Separation in 5 Msun Binaries

    Science.gov (United States)

    Evans, Nancy R.; Bond, H. E.; Schaefer, G.; Mason, B. D.; Karovska, M.; Tingle, E.

    2013-01-01

    Cepheids (5 Msun stars) provide an excellent sample for determining the binary properties of fairly massive stars. International Ultraviolet Explorer (IUE) observations of Cepheids brighter than 8th magnitude resulted in a list of ALL companions more massive than 2.0 Msun uniformly sensitive to all separations. Hubble Space Telescope Wide Field Camera 3 (WFC3) has resolved three of these binaries (Eta Aql, S Nor, and V659 Cen). Combining these separations with orbital data in the literature, we derive an unbiased distribution of binary separations for a sample of 18 Cepheids, and also a distribution of mass ratios. The distribution of orbital periods shows that the 5 Msun binaries prefer shorter periods than 1 Msun stars, reflecting differences in star formation processes.

  12. Mesoscopic model for binary fluids

    Science.gov (United States)

    Echeverria, C.; Tucci, K.; Alvarez-Llamoza, O.; Orozco-Guillén, E. E.; Morales, M.; Cosenza, M. G.

    2017-10-01

    We propose a model for studying binary fluids based on the mesoscopic molecular simulation technique known as multiparticle collision, where the space and state variables are continuous, and time is discrete. We include a repulsion rule to simulate segregation processes that does not require calculation of the interaction forces between particles, so binary fluids can be described on a mesoscopic scale. The model is conceptually simple and computationally efficient; it maintains Galilean invariance and conserves the mass and energy in the system at the micro- and macro-scale, whereas momentum is conserved globally. For a wide range of temperatures and densities, the model yields results in good agreement with the known properties of binary fluids, such as the density profile, interface width, phase separation, and phase growth. We also apply the model to the study of binary fluids in crowded environments with consistent results.

  13. Some properties of spectral binary stars

    International Nuclear Information System (INIS)

    Krajcheva, Z.T.; Popova, E.I.; Tutukov, A.V.; Yungel'son, L.R.; AN SSSR, Moscow. Astronomicheskij Sovet)

    1978-01-01

    Statistical investigations of spectra binary stars are carried out. Binary systems consisting of main sequence stars are considered. For 826 binary stars masses of components, ratios of component masses, semiaxes of orbits and orbital angular momenta are calculated. The distributions of these parameters and their correlations are analyzed. The dependences of statistical properties of spectral binary stars on their origin and evolution are discussed

  14. Gravitational redshift from a binary system

    Energy Technology Data Exchange (ETDEWEB)

    Steklain, Andre [Universidade Tecnologica Federal do Parana (UTFPR), PR (Brazil)

    2011-07-01

    Full text: In this work we study the gravitational redshift of a binary system in general relativity. We employ a mixed metric obtained from the matching of a 1PN metric with two perturbed Schwarzschild metrics, based on previous works [Alvi, Phys. Rev. D, 61, 124013 (2000)]. This metric is well known, and has been considered for several applications [Steklain et al, Phys. Lett. A, 373, 188, (2009)]. We consider a massless observer in a timelike geodesic of this metric measuring the redshift of the system. The observer concentrates the redshift measurements in one of the massive bodies and is influenced by the mass of the second body. We find that there is a substantial contribution of the second mass in some cases. We compare with experimental data obtained for real binary systems of white dwarfs [Vennes et al, Astroph. J., L37 (1991)]. We also discuss these results for more massive systems, and make some predictions for very massive systems, like black holes, although it extrapolates the limit of the 1PN approximation used. Is well known that the major contribution of the observed redshift is from the universe expansion, but these results indicate that the influence of the gravitational redshift may be underestimated at some systems. (author)

  15. Multilevel Cross-Dependent Binary Longitudinal Data

    KAUST Repository

    Serban, Nicoleta

    2013-10-16

    We provide insights into new methodology for the analysis of multilevel binary data observed longitudinally, when the repeated longitudinal measurements are correlated. The proposed model is logistic functional regression conditioned on three latent processes describing the within- and between-variability, and describing the cross-dependence of the repeated longitudinal measurements. We estimate the model components without employing mixed-effects modeling but assuming an approximation to the logistic link function. The primary objectives of this article are to highlight the challenges in the estimation of the model components, to compare two approximations to the logistic regression function, linear and exponential, and to discuss their advantages and limitations. The linear approximation is computationally efficient whereas the exponential approximation applies for rare events functional data. Our methods are inspired by and applied to a scientific experiment on spectral backscatter from long range infrared light detection and ranging (LIDAR) data. The models are general and relevant to many new binary functional data sets, with or without dependence between repeated functional measurements.

  16. Modeling and analysis of advanced binary cycles

    Energy Technology Data Exchange (ETDEWEB)

    Gawlik, K.

    1997-12-31

    A computer model (Cycle Analysis Simulation Tool, CAST) and a methodology have been developed to perform value analysis for small, low- to moderate-temperature binary geothermal power plants. The value analysis method allows for incremental changes in the levelized electricity cost (LEC) to be determined between a baseline plant and a modified plant. Thermodynamic cycle analyses and component sizing are carried out in the model followed by economic analysis which provides LEC results. The emphasis of the present work is on evaluating the effect of mixed working fluids instead of pure fluids on the LEC of a geothermal binary plant that uses a simple Organic Rankine Cycle. Four resources were studied spanning the range of 265{degrees}F to 375{degrees}F. A variety of isobutane and propane based mixtures, in addition to pure fluids, were used as working fluids. This study shows that the use of propane mixtures at a 265{degrees}F resource can reduce the LEC by 24% when compared to a base case value that utilizes commercial isobutane as its working fluid. The cost savings drop to 6% for a 375{degrees}F resource, where an isobutane mixture is favored. Supercritical cycles were found to have the lowest cost at all resources.

  17. Mixing effects in the crystallization of supercooled quantum binary liquids

    International Nuclear Information System (INIS)

    Kühnel, M.; Kalinin, A.; Fernández, J. M.; Tejeda, G.; Moreno, E.; Montero, S.; Tramonto, F.; Galli, D. E.; Nava, M.; Grisenti, R. E.

    2015-01-01

    By means of Raman spectroscopy of liquid microjets, we have investigated the crystallization process of supercooled quantum liquid mixtures composed of parahydrogen (pH 2 ) or orthodeuterium (oD 2 ) diluted with small amounts of neon. We show that the introduction of the Ne impurities affects the crystallization kinetics in terms of a significant reduction of the measured pH 2 and oD 2 crystal growth rates, similarly to what found in our previous work on supercooled pH 2 -oD 2 liquid mixtures [Kühnel et al., Phys. Rev. B 89, 180201(R) (2014)]. Our experimental results, in combination with path-integral simulations of the supercooled liquid mixtures, suggest in particular a correlation between the measured growth rates and the ratio of the effective particle sizes originating from quantum delocalization effects. We further show that the crystalline structure of the mixtures is also affected to a large extent by the presence of the Ne impurities, which likely initiate the freezing process through the formation of Ne-rich crystallites

  18. Energetics of binary mixed culture of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Jane

    2010-12-20

    Dec 20, 2010 ... 1Biochemical Engineering Research Laboratory, Department of Chemical Engineering, Ladoke Akintola University of. Technology, Ogbomoso .... of the organic substrate (phenol in this case) and biomass, respec- tively. The carbon and .... Solomon et al., 1994). It has been shown that in this approach as S.

  19. Mixing effects in the crystallization of supercooled quantum binary liquids

    Energy Technology Data Exchange (ETDEWEB)

    Kühnel, M.; Kalinin, A. [Institut für Kernphysik, J. W. Goethe-Universität, Max-von-Laue-Str. 1, 60438 Frankfurt am Main (Germany); Fernández, J. M.; Tejeda, G.; Moreno, E.; Montero, S. [Laboratory of Molecular Fluid Dynamics, Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid (Spain); Tramonto, F.; Galli, D. E. [Laboratorio di Calcolo Parallelo e di Simulazioni di Materia Condensata, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Nava, M. [Laboratorio di Calcolo Parallelo e di Simulazioni di Materia Condensata, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Computational Science, Department of Chemistry and Applied Biosciences, ETH Zurich, USI Campus, Via Giuseppe Buffi 13, CH-6900 Lugano (Switzerland); Grisenti, R. E. [Institut für Kernphysik, J. W. Goethe-Universität, Max-von-Laue-Str. 1, 60438 Frankfurt am Main (Germany); GSI - Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany)

    2015-08-14

    By means of Raman spectroscopy of liquid microjets, we have investigated the crystallization process of supercooled quantum liquid mixtures composed of parahydrogen (pH{sub 2}) or orthodeuterium (oD{sub 2}) diluted with small amounts of neon. We show that the introduction of the Ne impurities affects the crystallization kinetics in terms of a significant reduction of the measured pH{sub 2} and oD{sub 2} crystal growth rates, similarly to what found in our previous work on supercooled pH{sub 2}-oD{sub 2} liquid mixtures [Kühnel et al., Phys. Rev. B 89, 180201(R) (2014)]. Our experimental results, in combination with path-integral simulations of the supercooled liquid mixtures, suggest in particular a correlation between the measured growth rates and the ratio of the effective particle sizes originating from quantum delocalization effects. We further show that the crystalline structure of the mixtures is also affected to a large extent by the presence of the Ne impurities, which likely initiate the freezing process through the formation of Ne-rich crystallites.

  20. Binary Systems and the Initial Mass Function

    Science.gov (United States)

    Malkov, O. Yu.

    2017-07-01

    In the present paper we discuss advantages and disadvantages of binary stars, which are important for star formation history determination. We show that to make definite conclusions of the initial mass function shape, it is necessary to study binary population well enough to correct the luminosity function for unresolved binaries; to construct the mass-luminosity relation based on wide binaries data, and to separate observational mass functions of primaries, of secondaries, and of unresolved binaries.

  1. Enthalpies of a binary alloy during solidification

    Science.gov (United States)

    Poirier, D. R.; Nandapurkar, P.

    1988-01-01

    The purpose of the paper is to present a method of calculating the enthalpy of a dendritic alloy during solidification. The enthalpies of the dendritic solid and interdendritic liquid of alloys of the Pb-Sn system are evaluated, but the method could be applied to other binaries, as well. The enthalpies are consistent with a recent evaluation of the thermodynamics of Pb-Sn alloys and with the redistribution of solute in the same during dendritic solidification. Because of the heat of mixing in Pb-Sn alloys, the interdendritic liquid of hypoeutectic alloys (Pb-rich) of less than 50 wt pct Sn has enthalpies that increase as temperature decreases during solidification.

  2. Asymptotic Limits for Transport in Binary Stochastic Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Prinja, A. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-05-01

    The Karhunen-Loeve stochastic spectral expansion of a random binary mixture of immiscible fluids in planar geometry is used to explore asymptotic limits of radiation transport in such mixtures. Under appropriate scalings of mixing parameters - correlation length, volume fraction, and material cross sections - and employing multiple- scale expansion of the angular flux, previously established atomic mix and diffusion limits are reproduced. When applied to highly contrasting material properties in the small cor- relation length limit, the methodology yields a nonstandard reflective medium transport equation that merits further investigation. Finally, a hybrid closure is proposed that produces both small and large correlation length limits of the closure condition for the material averaged equations.

  3. Thermodynamic modeling of saturated liquid compositions and densities for asymmetric binary systems composed of carbon dioxide, alkanes and alkanols

    International Nuclear Information System (INIS)

    Bayestehparvin, Bita; Nourozieh, Hossein; Kariznovi, Mohammad; Abedi, Jalal

    2015-01-01

    Highlights: • Phase behavior of the binary systems containing largely different components. • Equation of state modeling of binary polar and non-polar systems by utilizing different mixing rules. • Three different mixing rules (one-parameter, two-parameters and Wong–Sandler) coupled with Peng–Robinson equation of state. • Two-parameter mixing rule shows promoting results compared to one-parameter mixing rule. • Wong–Sandler mixing rule is unable to predict saturated liquid densities with sufficient accuracy. - Abstract: The present study mainly focuses on the phase behavior modeling of asymmetric binary mixtures. Capability of different mixing rules and volume shift in the prediction of solubility and saturated liquid density has been investigated. Different binary systems of (alkane + alkanol), (alkane + alkane), (carbon dioxide + alkanol), and (carbon dioxide + alkane) are considered. The composition and the density of saturated liquid phase at equilibrium condition are the properties of interest. Considering composition and saturated liquid density of different binary systems, three main objectives are investigated. First, three different mixing rules (one-parameter, two parameters and Wong–Sandler) coupled with Peng–Robinson equation of state were used to predict the equilibrium properties. The Wong–Sandler mixing rule was utilized with the non-random two-liquid (NRTL) model. Binary interaction coefficients and NRTL model parameters were optimized using the Levenberg–Marquardt algorithm. Second, to improve the density prediction, the volume translation technique was applied. Finally, Two different approaches were considered to tune the equation of state; regression of experimental equilibrium compositions and densities separately and spontaneously. The modeling results show that there is no superior mixing rule which can predict the equilibrium properties for different systems. Two-parameter and Wong–Sandler mixing rule show promoting

  4. Determination and correlation of solubility and thermodynamic properties of pyraclostrobin in pure and binary solvents

    International Nuclear Information System (INIS)

    Yang, Peng; Du, Shichao; Qin, Yujia; Zhao, Kaifei; Li, Kangli; Hou, Baohong; Gong, Junbo

    2016-01-01

    Highlights: • The solubility data of pyraclostrobin in pure and binary solvents were determined and correlated. • The theory of solubility parameter was used to explain the cosolvency in binary solvents. • A modified mixing rule was proposed to calculate the solubility parameter of binary solvents. • The dissolution thermodynamic properties were calculated and discussed. - Abstract: The solubility of pyraclostrobin in five pure solvents and two binary solvent mixtures was measured from 283.15 K to 308.15 K using a static analytical method. Solubility in five pure solvents was well correlated by the modified Apelblat equation and Wilson model. While the CNIBS/R–K model was applied to correlate the solubility in two binary solvent mixtures, the correlation showed good agreement with experimental results. The solubility of pyraclostrobin reaches its maximum value at a certain cyclohexane mole fraction in the two binary solvent mixtures. The solubility parameter of pyraclostrobin was calculated by the Fedors method and a new modified mixing rule with preferable applicability was proposed to determine the solubility parameter of solvents. Then the co-solvency in the binary solvent mixtures can be explained based on the obtained solubility parameters. In a addition, the dissolution thermodynamic properties were calculated from the experimental values using the Wilson model.

  5. Hidden slow pulsars in binaries

    Science.gov (United States)

    Tavani, Marco; Brookshaw, Leigh

    1993-01-01

    The recent discovery of the binary containing the slow pulsar PSR 1718-19 orbiting around a low-mass companion star adds new light on the characteristics of binary pulsars. The properties of the radio eclipses of PSR 1718-19 are the most striking observational characteristics of this system. The surface of the companion star produces a mass outflow which leaves only a small 'window' in orbital phase for the detection of PSR 1718-19 around 400 MHz. At this observing frequency, PSR 1718-19 is clearly observable only for about 1 hr out of the total 6.2 hr orbital period. The aim of this Letter is twofold: (1) to model the hydrodynamical behavior of the eclipsing material from the companion star of PSR 1718-19 and (2) to argue that a population of binary slow pulsars might have escaped detection in pulsar surveys carried out at 400 MHz. The possible existence of a population of partially or totally hidden slow pulsars in binaries will have a strong impact on current theories of binary evolution of neutron stars.

  6. Sneutrino mixing

    International Nuclear Information System (INIS)

    Grossman, Y.

    1997-10-01

    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

  7. The Young Visual Binary Survey

    Science.gov (United States)

    Prato, Lisa; Avilez, Ian; Lindstrom, Kyle; Graham, Sean; Sullivan, Kendall; Biddle, Lauren; Skiff, Brian; Nofi, Larissa; Schaefer, Gail; Simon, Michal

    2018-01-01

    Differences in the stellar and circumstellar properties of the components of young binaries provide key information about star and disk formation and evolution processes. Because objects with separations of a few to a few hundred astronomical units share a common environment and composition, multiple systems allow us to control for some of the factors which play into star formation. We are completing analysis of a rich sample of about 100 pre-main sequence binaries and higher order multiples, primarily located in the Taurus and Ophiuchus star forming regions. This poster will highlight some of out recent, exciting results. All reduced spectra and the results of our analysis will be publicly available to the community at http://jumar.lowell.edu/BinaryStars/. Support for this research was provided in part by NSF award AST-1313399 and by NASA Keck KPDA funding.

  8. Evolution in close binary systems

    International Nuclear Information System (INIS)

    Yungel'son, L.R.; Masevich, A.G.

    1983-01-01

    Duality is the property most typical of stars. If one investigates how prevalent double stars are, making due allowance for selection effects, one finds that as many as 90 percent of all stars are paired. Contrary to tradition it is single stars that are out of the ordinary, and as will be shown presently even some of these may have been formed by coalescence of the members of binary systems. This review deals with the evolution of close binaries, defined as double-star systems whose evolution entails exchange of material between the two components

  9. Highly stable bilayer of LiPON and B2O3 added Li1.5Al0.5Ge1.5(PO4) solid electrolytes for non-aqueous rechargeable Li-O2 batteries

    International Nuclear Information System (INIS)

    Jadhav, Harsharaj S.; Kalubarme, Ramchandra S.; Jadhav, Arvind H.; Seo, Jeong Gil

    2016-01-01

    Highlights: • LiPON thin film deposited by RF-sputtering technique. • The effect of deposition temperature on ionic conductivity was investigated. • The LiPON/B-LAGP composite was successfully employed in Li-O 2 battery. • LiPON interlayer enhances stability of B-LAGP in contact with Li-metal. - Abstract: Lithium ion conducting membranes are barely studied, although they are essentially indispensable for building Li-air batteries composed of aqueous and non-aqueous electrolytes for long-term operation. Lithium phosphorous oxynitride (LiPON) thin films were deposited by RF-sputtering technique on B 2 O 3 -added lithium aluminum germanium phosphate (B-LAGP). Compact thin amorphous LiPON layer could act as a protective interlayer for B-LAGP by separating it from Li metal electrode and mitigate the reaction between them. Large electrochemical stability window (0–5 V) of LiPON/B-LAGP solid electrolyte shows promising feasibility for applications in all lithium based batteries. The aprotic Li-O 2 cell with protected lithium electrode configuration employing LiPON/B-LAGP solid electrolyte has exhibited reasonable cycling stability with long-life of 52 cycles at a limited capacity of 1000 mA h g −1 .

  10. Synthesis and Determination of pKa Values of Some New 3,4-Disubstituted-4,5-Dihydro-1H-1,2,4-triazol-5-one Derivatives in Non-aqueous Solvents

    Directory of Open Access Journals (Sweden)

    Mustafa Özdemir

    2004-03-01

    Full Text Available 3-Alkyl(Aryl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2 reacted with 2-furoyl chloride and thiophene-2-carbonyl chloride to afford the corresponding 3- alkyl(aryl-4-(2-furoylamino-4,5-dihydro-1H-1,2,4-triazol-5-ones (3 and 3-alkyl(aryl- 4-(2-thienylcarbonylamino-4,5-dihydro-1H-1,2,4-triazol-5-ones (4, respectively. The new compounds synthesized were characterized by using IR, 1H-NMR, 13C-NMR and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 3 and 4 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide and acetonitrile. The half-neutralization potential values and the corresponding pKa values were determined for all cases.

  11. The Binary Ties that Bind

    Science.gov (United States)

    Rose, Mike

    2008-01-01

    As any reader of "About Campus" knows, binary oppositions contribute to the definitions of institutional types--the trade school versus the liberal arts college, for example. They help define disciplines and subdisciplines and the status differentials among them: consider the difference in intellectual cachet as one moves from linguistics to…

  12. Optimally cloned binary coherent states

    DEFF Research Database (Denmark)

    Mueller, C. R.; Leuchs, G.; Marquardt, Ch

    2017-01-01

    their quantum-optimal clones. We analyze the Wigner function and the cumulants of the clones, and we conclude that optimal cloning of binary coherent states requires a nonlinearity above second order. We propose several practical and near-optimal cloning schemes and compare their cloning fidelity to the optimal...

  13. Subluminous X-ray binaries

    NARCIS (Netherlands)

    Armas Padilla, M.

    2013-01-01

    The discovery of the first X-ray binary, Scorpius X-1, by Giacconi et al. (1962), marked the birth of X-ray astronomy. Following that discovery, many additional X-ray sources where found with the first generation of X-ray rockets and observatories (e.g., UHURU and Einstein). The short-timescale

  14. Misclassification in binary choice models

    Czech Academy of Sciences Publication Activity Database

    Meyer, B. D.; Mittag, Nikolas

    2017-01-01

    Roč. 200, č. 2 (2017), s. 295-311 ISSN 0304-4076 R&D Projects: GA ČR(CZ) GJ16-07603Y Institutional support: Progres-Q24 Keywords : measurement error * binary choice models * program take-up Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 1.633, year: 2016

  15. Misclassification in binary choice models

    Czech Academy of Sciences Publication Activity Database

    Meyer, B. D.; Mittag, Nikolas

    2017-01-01

    Roč. 200, č. 2 (2017), s. 295-311 ISSN 0304-4076 Institutional support: RVO:67985998 Keywords : measurement error * binary choice models * program take-up Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 1.633, year: 2016

  16. Binary logic is rich enough

    International Nuclear Information System (INIS)

    Zapatrin, R.R.

    1992-01-01

    Given a finite ortholattice L, the *-semigroup is explicitly built whose annihilator ortholattice is isomorphic to L. Thus, it is shown that any finite quantum logic is the additive part of a binary logic. Some areas of possible applications are outlined. 7 refs

  17. Thermodynamic properties of some gallium-based binary alloys

    International Nuclear Information System (INIS)

    Awe, O.E.; Odusote, Y.A.; Akinlade, O.; Hussain, L.A.

    2008-01-01

    We have studied the concentration dependence of the free energy of mixing, concentration-concentration fluctuations in the long-wavelength limit, the chemical short-range order parameter, the enthalpy and entropy of mixing of Ga-Zn, Ga-Mg and Al-Ga binary alloys at different temperatures using a quasi-chemical approximation for compound forming binary alloys and that for simple regular alloys. From the study of the thermodynamic quantities, we observed that thermodynamic properties of Ga-Zn and Al-Ga exhibit positive deviations from Raoultian behaviour, while Ga-Mg exhibits negative deviation. Hence, this study reveals that both Ga-Zn and Al-Ga are segregating systems, while chemical order exists in Ga-Mg alloy in the whole concentration range. Furthermore, our investigation indicate that Al-Ga binary alloy have a tendency to exhibit ideal mixture behaviour in the concentration range 0≤c Al ≤0.30 and 0.7≤c Al ≤1

  18. Astronomy of binary and multiple stars

    International Nuclear Information System (INIS)

    Tokovinin, A.A.

    1984-01-01

    Various types of binary stars and methods for their observation are described in a popular form. Some models of formation and evolution of binary and multiple star systems are presented. It is concluded that formation of binary and multiple stars is a regular stage in the process of star production

  19. Coevolution of Binaries and Circumbinary Gaseous Disks

    Science.gov (United States)

    Fleming, David; Quinn, Thomas R.

    2018-04-01

    The recent discoveries of circumbinary planets by Kepler raise questions for contemporary planet formation models. Understanding how these planets form requires characterizing their formation environment, the circumbinary protoplanetary disk, and how the disk and binary interact. The central binary excites resonances in the surrounding protoplanetary disk that drive evolution in both the binary orbital elements and in the disk. To probe how these interactions impact both binary eccentricity and disk structure evolution, we ran N-body smooth particle hydrodynamics (SPH) simulations of gaseous protoplanetary disks surrounding binaries based on Kepler 38 for 10^4 binary orbital periods for several initial binary eccentricities. We find that nearly circular binaries weakly couple to the disk via a parametric instability and excite disk eccentricity growth. Eccentric binaries strongly couple to the disk causing eccentricity growth for both the disk and binary. Disks around sufficiently eccentric binaries strongly couple to the disk and develop an m = 1 spiral wave launched from the 1:3 eccentric outer Lindblad resonance (EOLR). This wave corresponds to an alignment of gas particle longitude of periastrons. We find that in all simulations, the binary semi-major axis decays due to dissipation from the viscous disk.

  20. Formation and evolution of compact binaries

    NARCIS (Netherlands)

    Sluijs, Marcel Vincent van der

    2006-01-01

    In this thesis we investigate the formation and evolution of compact binaries. Chapters 2 through 4 deal with the formation of luminous, ultra-compact X-ray binaries in globular clusters. We show that the proposed scenario of magnetic capture produces too few ultra-compact X-ray binaries to explain

  1. Non-aqueous titration of benzotrifuroxan (BTF)

    Energy Technology Data Exchange (ETDEWEB)

    Selig, W.

    1978-01-01

    This compound can be titrated potentiometrically as an acid with tetrabutylammonium hydroxide in dimethylformamide, dimethylsulfoxide, acetone, pyridine, tetramethylguanidine. The solvent of choice is dimethylformamide which yields the steepest titration curve and the lowest standard deviation. The equivalent weight of benzotrifuroxan is dependent on the solvent used indicating a strong interaction with the solvent. In dimethylformamide, the equivalent weight of benzotrifuroxan is 151.3, corresponding to 1.67 equivalents per mole.

  2. Lyoluminescence in a non-aqueous medium

    International Nuclear Information System (INIS)

    Dixon, S.M.; Ettinger, K.V.

    1990-01-01

    Lyoluminescence of mannose in water has been compared with that in water-methanol mixtures and in pure methanol. The light yield is larger in methanol by a factor, dependent upon the dose, which can reach 20 times. The yield in methanol increases with the temperature of the solvent. The nature of the dose response curve and the onset of saturation are the same. The fading on storage is faster for readout in methanol. (author)

  3. Binary Linear-Time Erasure Decoding for Non-Binary LDPC codes

    OpenAIRE

    Savin, Valentin

    2009-01-01

    In this paper, we first introduce the extended binary representation of non-binary codes, which corresponds to a covering graph of the bipartite graph associated with the non-binary code. Then we show that non-binary codewords correspond to binary codewords of the extended representation that further satisfy some simplex-constraint: that is, bits lying over the same symbol-node of the non-binary graph must form a codeword of a simplex code. Applied to the binary erasure channel, this descript...

  4. Solid/liquid interfacial free energies in binary systems

    Science.gov (United States)

    Nason, D.; Tiller, W. A.

    1973-01-01

    Description of a semiquantitative technique for predicting the segregation characteristics of smooth interfaces between binary solid and liquid solutions in terms of readily available thermodynamic parameters of the bulk solutions. A lattice-liquid interfacial model and a pair-bonded regular solution model are employed in the treatment with an accommodation for liquid interfacial entropy. The method is used to calculate the interfacial segregation and the free energy of segregation for solid-liquid interfaces between binary solutions for the (111) boundary of fcc crystals. The zone of compositional transition across the interface is shown to be on the order of a few atomic layers in width, being moderately narrower for ideal solutions. The free energy of the segregated interface depends primarily upon the solid composition and the heats of fusion of the component atoms, the composition difference of the solutions, and the difference of the heats of mixing of the solutions.

  5. Composition measurements of binary mixture droplets by rainbow refractometry.

    Science.gov (United States)

    Wilms, J; Weigand, B

    2007-04-10

    So far, refractive index measurements by rainbow refractometry have been used to determine the temperature of single droplets and ensembles of droplets. Rainbow refractometry is, for the first time, to the best of our knowledge, applied to measure composition histories of evaporating, binary mixture droplets. An evaluation method is presented that makes use of Airy theory and the simultaneous size measurement by Mie scattering imaging. The method further includes an empirical correction function for a certain diameter and refractive index range. The measurement uncertainty was investigated by numerical simulations with Lorenz-Mie theory. For the experiments, an optical levitation setup was used allowing for long measurement periods. Temperature measurements of single-component droplets at different temperature levels are shown to demonstrate the accuracy of rainbow refractometry. Measurements of size and composition histories of binary mixture droplets are presented for two different mixtures. Experimental results show good agreement with numerical results using a rapid-mixing model.

  6. Composition measurements of binary mixture droplets by rainbow refractometry

    International Nuclear Information System (INIS)

    Wilms, J.; Weigand, B.

    2007-01-01

    So far, refractive index measurements by rainbow refractometry have been used to determine the temperature of single droplets and ensembles of droplets. Rainbow refractometry is, for the first time, to the best of our knowledge, applied to measure composition histories of evaporating, binary mixture droplets. An evaluation method is presented that makes use of Airy theory and the simultaneous size measurement by Mie scattering imaging. The method further includes an empirical correction function for a certain diameter and refractive index range. The measurement uncertainty was investigated by numerical simulations with Lorenz-Mie theory. For the experiments, an optical levitation setup was used allowing for long measurement periods. Temperature measurements of single-component droplets at different temperature levels are shown to demonstrate the accuracy of rainbow refractometry. Measurements of size and composition histories of binary mixture droplets are presented for two different mixtures. Experimental results show good agreement with numerical results using a rapid-mixing model

  7. Analysis and Design of Binary Message-Passing Decoders

    DEFF Research Database (Denmark)

    Lechner, Gottfried; Pedersen, Troels; Kramer, Gerhard

    2012-01-01

    Binary message-passing decoders for low-density parity-check (LDPC) codes are studied by using extrinsic information transfer (EXIT) charts. The channel delivers hard or soft decisions and the variable node decoder performs all computations in the L-value domain. A hard decision channel results...... message-passing decoders. Finally, it is shown that errors on cycles consisting only of degree two and three variable nodes cannot be corrected and a necessary and sufficient condition for the existence of a cycle-free subgraph is derived....... in the well-know Gallager B algorithm, and increasing the output alphabet from hard decisions to two bits yields a gain of more than 1.0 dB in the required signal to noise ratio when using optimized codes. The code optimization requires adapting the mixing property of EXIT functions to the case of binary...

  8. The use of continuous data versus binary data in MTC models: a case study in rheumatoid arthritis.

    Science.gov (United States)

    Schmitz, Susanne; Adams, Roisin; Walsh, Cathal

    2012-11-06

    Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. When sufficient head to head evidence is not available Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates. While models can be fit to a broad range of efficacy measures, this paper illustrates the advantages of using continuous outcome measures compared to binary outcome measures. Using a case study in rheumatoid arthritis a Bayesian mixed treatment comparison model is fit to estimate the relative efficacy of five anti-TNF agents currently licensed in Europe. The model is fit for the continuous HAQ improvement outcome measure and a binary version thereof as well as for the binary ACR response measure and the underlying continuous effect. Results are compared regarding their power to detect differences between treatments. Sixteen randomized controlled trials were included for the analysis. For both analyses, based on the HAQ improvement as well as based on the ACR response, differences between treatments detected by the binary outcome measures are subsets of the differences detected by the underlying continuous effects. The information lost when transforming continuous data into a binary response measure translates into a loss of power to detect differences between treatments in mixed treatment comparison models. Binary outcome measures are therefore less sensitive to change than continuous measures. Furthermore the choice of cut-off point to construct the binary measure also impacts the relative efficacy estimates.

  9. The use of continuous data versus binary data in MTC models: A case study in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Schmitz Susanne

    2012-11-01

    Full Text Available Abstract Background Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. When sufficient head to head evidence is not available Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates. While models can be fit to a broad range of efficacy measures, this paper illustrates the advantages of using continuous outcome measures compared to binary outcome measures. Methods Using a case study in rheumatoid arthritis a Bayesian mixed treatment comparison model is fit to estimate the relative efficacy of five anti-TNF agents currently licensed in Europe. The model is fit for the continuous HAQ improvement outcome measure and a binary version thereof as well as for the binary ACR response measure and the underlying continuous effect. Results are compared regarding their power to detect differences between treatments. Results Sixteen randomized controlled trials were included for the analysis. For both analyses, based on the HAQ improvement as well as based on the ACR response, differences between treatments detected by the binary outcome measures are subsets of the differences detected by the underlying continuous effects. Conclusions The information lost when transforming continuous data into a binary response measure translates into a loss of power to detect differences between treatments in mixed treatment comparison models. Binary outcome measures are therefore less sensitive to change than continuous measures. Furthermore the choice of cut-off point to construct the binary measure also impacts the relative efficacy estimates.

  10. Detecting Malicious Code by Binary File Checking

    Directory of Open Access Journals (Sweden)

    Marius POPA

    2014-01-01

    Full Text Available The object, library and executable code is stored in binary files. Functionality of a binary file is altered when its content or program source code is changed, causing undesired effects. A direct content change is possible when the intruder knows the structural information of the binary file. The paper describes the structural properties of the binary object files, how the content can be controlled by a possible intruder and what the ways to identify malicious code in such kind of files. Because the object files are inputs in linking processes, early detection of the malicious content is crucial to avoid infection of the binary executable files.

  11. Permutation Entropy for Random Binary Sequences

    Directory of Open Access Journals (Sweden)

    Lingfeng Liu

    2015-12-01

    Full Text Available In this paper, we generalize the permutation entropy (PE measure to binary sequences, which is based on Shannon’s entropy, and theoretically analyze this measure for random binary sequences. We deduce the theoretical value of PE for random binary sequences, which can be used to measure the randomness of binary sequences. We also reveal the relationship between this PE measure with other randomness measures, such as Shannon’s entropy and Lempel–Ziv complexity. The results show that PE is consistent with these two measures. Furthermore, we use PE as one of the randomness measures to evaluate the randomness of chaotic binary sequences.

  12. A template bank to search for gravitational waves from inspiralling compact binaries: I. Physical models

    International Nuclear Information System (INIS)

    Babak, S; Balasubramanian, R; Churches, D; Cokelaer, T; Sathyaprakash, B S

    2006-01-01

    Gravitational waves from coalescing compact binaries are searched for using the matched filtering technique. As the model waveform depends on a number of parameters, it is necessary to filter the data through a template bank covering the astrophysically interesting region of the parameter space. The choice of templates is defined by the maximum allowed drop in signal-to-noise ratio due to the discreteness of the template bank. In this paper we describe the template-bank algorithm that was used in the analysis of data from the Laser Interferometer Gravitational Wave Observatory (LIGO) and GEO 600 detectors to search for signals from binaries consisting of non-spinning compact objects. Using Monte Carlo simulations, we study the efficiency of the bank and show that its performance is satisfactory for the design sensitivity curves of ground-based interferometric gravitational wave detectors GEO 600, initial LIGO, advanced LIGO and Virgo. The bank is efficient in searching for various compact binaries such as binary primordial black holes, binary neutron stars, binary black holes, as well as a mixed binary consisting of a non-spinning black hole and a neutron star

  13. Mixing Ventilation

    DEFF Research Database (Denmark)

    Kandzia, Claudia; Kosonen, Risto; Melikov, Arsen Krikor

    In this guidebook most of the known and used in practice methods for achieving mixing air distribution are discussed. Mixing ventilation has been applied to many different spaces providing fresh air and thermal comfort to the occupants. Today, a design engineer can choose from large selection...

  14. Binary Effect of Fly Ash and Palm Oil Fuel Ash on Heat of Hydration Aerated Concrete

    Science.gov (United States)

    Mehmannavaz, Taha; Ismail, Mohammad; Radin Sumadi, Salihuddin; Rafique Bhutta, Muhammad Aamer; Samadi, Mostafa

    2014-01-01

    The binary effect of pulverized fuel ash (PFA) and palm oil fuel ash (POFA) on heat of hydration of aerated concrete was studied. Three aerated concrete mixes were prepared, namely, concrete containing 100% ordinary Portland cement (control sample or Type I), binary concrete made from 50% POFA (Type II), and ternary concrete containing 30% POFA and 20% PFA (Type III). It is found that the temperature increases due to heat of hydration through all the concrete specimens especially in the control sample. However, the total temperature rises caused by the heat of hydration through both of the new binary and ternary concrete were significantly lower than the control sample. The obtained results reveal that the replacement of Portland cement with binary and ternary materials is beneficial, particularly for mass concrete where thermal cracking due to extreme heat rise is of great concern. PMID:24696646

  15. What is the fundamental ion-specific series for anions and cations? Ion specificity in standard partial molar volumes of electrolytes and electrostriction in water and non-aqueous solvents.

    Science.gov (United States)

    Mazzini, Virginia; Craig, Vincent S J

    2017-10-01

    The importance of electrolyte solutions cannot be overstated. Beyond the ionic strength of electrolyte solutions the specific nature of the ions present is vital in controlling a host of properties. Therefore ion specificity is fundamentally important in physical chemistry, engineering and biology. The observation that the strengths of the effect of ions often follows well established series suggests that a single predictive and quantitative description of specific-ion effects covering a wide range of systems is possible. Such a theory would revolutionise applications of physical chemistry from polymer precipitation to drug design. Current approaches to understanding specific-ion effects involve consideration of the ions themselves, the solvent and relevant interfaces and the interactions between them. Here we investigate the specific-ion effects trends of standard partial molar volumes and electrostrictive volumes of electrolytes in water and eleven non-aqueous solvents. We choose these measures as they relate to bulk properties at infinite dilution, therefore they are the simplest electrolyte systems. This is done to test the hypothesis that the ions alone exhibit a specific-ion effect series that is independent of the solvent and unrelated to surface properties. The specific-ion effects trends of standard partial molar volumes and normalised electrostrictive volumes examined in this work show a fundamental ion-specific series that is reproduced across the solvents, which is the Hofmeister series for anions and the reverse lyotropic series for cations, supporting the hypothesis. This outcome is important in demonstrating that ion specificity is observed at infinite dilution and demonstrates that the complexity observed in the manifestation of specific-ion effects in a very wide range of systems is due to perturbations of solvent, surfaces and concentration on the underlying fundamental series. This knowledge will guide a general understanding of specific

  16. Development and validation of an analytical method for the separation and determination of major bioactive curcuminoids in Curcuma longa rhizomes and herbal products using non-aqueous capillary electrophoresis.

    Science.gov (United States)

    Anubala, S; Sekar, R; Nagaiah, K

    2014-06-01

    A simple, fast and efficient non-aqueous capillary electrophoresis method (NACE) was developed for the simultaneous determination of three major bioactive curcuminoids (CMNs) in Curcuma longa rhizomes and its herbal products. Good separation, resolution and reproducibility were achieved with the background electrolyte (BGE) consisting a mixture of 15.0 mM sodium tetraborate and 7.4 mM sodium hydroxide (NaOH) in 2:10:15 (v/v/v) of water, 1-propanol, and methanol. The influences of background electrolyte, sodium hydroxide, water, sodium dodecyl sulfate and hydroxylpropyl-β-cyclodextrin on separations were investigated. The separation was carried out in a fused-silica capillary tube with reverse polarity. Hydrodynamic injection of 25mbar for 12s was used for injecting samples and a voltage of 28 kV was applied for separation. The ultrasonication method was used for the extraction of CMNs from the turmeric herbal products and the extract was filtered and directly injected without any further treatments. The limits of detection and quantification were less than 5.0 and 14.6 µg/ml respectively for all CMNs. The percentage recoveries for CMNs were >97.2% (%RSD, <2.62). The results obtained by the method were compared with existing spectrophotometric and HPLC methods. The related compounds in the extract did not interfere in the determination of CMNs. The proposed NACE method is better than existing chromatographic and electrophoretic methods in terms of simple electrophoretic medium, fast analysis and good resolution. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A ROSAT Survey of Contact Binary Stars

    Science.gov (United States)

    Geske, M. T.; Gettel, S. J.; McKay, T. A.

    2006-01-01

    Contact binary stars are common variable stars that are all believed to emit relatively large fluxes of X-rays. In this work we combine a large new sample of contact binary stars derived from the ROTSE-I telescope with X-ray data from the ROSAT All Sky Survey (RASS) to estimate the X-ray volume emissivity of contact binary stars in the Galaxy. We obtained X-ray fluxes for 140 contact binaries from the RASS, as well as two additional stars observed by the XMM-Newton observatory. From these data we confirm the emission of X-rays from all contact binary systems, with typical luminosities of approximately 1.0×1030 ergs s-1. Combining calculated luminosities with an estimated contact binary space density, we find that contact binaries do not have strong enough X-ray emission to account for a significant portion of the Galactic X-ray background.

  18. Development of a new continuous process for mixing of complex non-Newtonian fluids

    Science.gov (United States)

    Migliozzi, Simona; Mazzei, Luca; Sochon, Bob; Angeli, Panagiota; Thames Multiphase Team; Coral Project Collaboration

    2017-11-01

    Design of new continuous mixing operations poses many challenges, especially when dealing with highly viscous non-Newtonian fluids. Knowledge of complex rheological behaviour of the working mixture is crucial for development of an efficient process. In this work, we investigate the mixing performance of two different static mixers and the effects of the mixture rheology on the manufacturing of novel non-aqueous-based oral care products using experimental and computational fluid dynamic methods. The two liquid phases employed, i.e. a carbomer suspension in polyethylene glycol and glycerol, start to form a gel when they mix. We studied the structure evolution of the liquid mixture using time-resolved rheometry and we obtained viscosity rheograms at different phase ratios from pressure drop measurements in a customized mini-channel. The numerical results and rheological model were validated with experimental measurements carried out in a specifically designed setup. EPSRS-CORAL.

  19. Binary evolution and observational constraints

    International Nuclear Information System (INIS)

    Loore, C. de

    1984-01-01

    The evolution of close binaries is discussed in connection with problems concerning mass and angular momentum losses. Theoretical and observational evidence for outflow of matter, leaving the system during evolution is given: statistics on total masses and mass ratios, effects of the accretion of the mass gaining component, the presence of streams, disks, rings, circumstellar envelopes, period changes, abundance changes in the atmosphere. The effects of outflowing matter on the evolution is outlined, and estimates of the fraction of matter expelled by the loser, and leaving the system, are given. The various time scales involved with evolution and observation are compared. Examples of non conservative evolution are discussed. Problems related to contact phases, on mass and energy losses, in connection with entropy changes are briefly analysed. For advanced stages the disruption probabilities for supernova explosions are examined. A global picture is given for the evolution of massive close binaries, from ZAMS, through WR phases, X-ray phases, leading to runaway pulsars or to a binary pulsar and later to a millisecond pulsar. (Auth.)

  20. X rays from radio binaries

    International Nuclear Information System (INIS)

    Apparao, K.M.V.

    1977-01-01

    Reference is made to the radio binary systems CC Cas, AR Lac, β Per (Algol), β Lyr, b Per and Cyg X-1. It is stated that a thermal interpretation of the radiation from Algol requires a much larger x-ray flux than the observed value of 3.8 x 10 -11 erg/cm 2 /sec/keV in the 2 to 6 keV energy range. Observations of some non-thermal flares, together with the small size of the radio source in Algol, indicate that the radio emission is non-thermal in nature. The radio emission is interpreted as synchrotron radiation and it is suggested that the observed x-ray emission is due to inverse Compton scattering of the light of the primary star by the radio electrons. The x-ray emission from other radio binaries is also calculated using this model. The energy for the radio electrons can arise from annihilation of magnetic lines connecting the binary stars, twisted by the rotation of the stars. (U.K.)

  1. Heat of mixing and morphological stability

    Science.gov (United States)

    Nandapurkar, P.; Poirier, D. R.

    1988-01-01

    A mathematical model, which incorporates heat of mixing in the energy balance, has been developed to analyze the morphological stability of a planar solid-liquid interface during the directional solidification of a binary alloy. It is observed that the stability behavior is almost that predicted by the analysis of Mullins and Sekerka (1963) at low growth velocities, while deviations in the critical concentration of about 20-25 percent are observed under rapid solidification conditions for certain systems. The calculations indicate that a positive heat of mixing makes the planar interface more unstable, whereas a negative heat of mixing makes it more stable, in terms of the critical concentration.

  2. Global symplectic structure-preserving integrators for spinning compact binaries

    Science.gov (United States)

    Zhong, Shuang-Ying; Wu, Xin; Liu, San-Qiu; Deng, Xin-Fa

    2010-12-01

    This paper deals mainly with the application of the second-order symplectic implicit midpoint rule and its symmetric compositions to a post-Newtonian Hamiltonian formulation with canonical spin variables in relativistic compact binaries. The midpoint rule, as a basic algorithm, is directly used to integrate the completely canonical Hamiltonian system. On the other hand, there are symmetric composite methods based on a splitting of the Hamiltonian into two parts: the Newtonian part associated with a Kepler motion, and a perturbation part involving the orbital post-Newtonian and spin contributions, where the Kepler flow has an analytic solution and the perturbation can be calculated by the midpoint rule. An example is the second-order mixed leapfrog symplectic integrator with one stage integration of the perturbation flow and two semistage computations of the Kepler flow at every integration step. Also, higher-order composite methods such as the Forest-Ruth fourth-order symplectic integrator and its optimized algorithm are applicable. Various numerical tests including simulations of chaotic orbits show that the mixed leapfrog integrator is always superior to the midpoint rule in energy accuracy, while both of them are almost equivalent in computational efficiency. Particularly, the optimized fourth-order algorithm compared with the mixed leapfrog scheme provides good precision and needs no expensive additional computational time. As a result, it is worth performing a more detailed and careful examination of the dynamical structure of chaos and order in the parameter windows and phase space of the binary system.

  3. Structuring effects in binary nucleation : Molecular dynamics simulatons and coarse-grained nucleation theory

    NARCIS (Netherlands)

    Braun, S.; Kraska, T.; Kalikmanov, V.I.

    2013-01-01

    Binary clusters formed by vapor-liquid nucleation are frequently nonhomogeneous objects in which components are not well mixed. The structure of a cluster plays an important role in nucleation and cluster growth. We demonstrate structuring effects by studying high-pressure nucleation and cluster

  4. GALAXY ROTATION AND RAPID SUPERMASSIVE BINARY COALESCENCE

    Energy Technology Data Exchange (ETDEWEB)

    Holley-Bockelmann, Kelly [Vanderbilt University, Nashville, TN (United States); Khan, Fazeel Mahmood, E-mail: k.holley@vanderbilt.edu [Institute of Space Technology (IST), Islamabad (Pakistan)

    2015-09-10

    Galaxy mergers usher the supermassive black hole (SMBH) in each galaxy to the center of the potential, where they form an SMBH binary. The binary orbit shrinks by ejecting stars via three-body scattering, but ample work has shown that in spherical galaxy models, the binary separation stalls after ejecting all the stars in its loss cone—this is the well-known final parsec problem. However, it has been shown that SMBH binaries in non-spherical galactic nuclei harden at a nearly constant rate until reaching the gravitational wave regime. Here we use a suite of direct N-body simulations to follow SMBH binary evolution in both corotating and counterrotating flattened galaxy models. For N > 500 K, we find that the evolution of the SMBH binary is convergent and is independent of the particle number. Rotation in general increases the hardening rate of SMBH binaries even more effectively than galaxy geometry alone. SMBH binary hardening rates are similar for co- and counterrotating galaxies. In the corotating case, the center of mass of the SMBH binary settles into an orbit that is in corotation resonance with the background rotating model, and the coalescence time is roughly a few 100 Myr faster than a non-rotating flattened model. We find that counterrotation drives SMBHs to coalesce on a nearly radial orbit promptly after forming a hard binary. We discuss the implications for gravitational wave astronomy, hypervelocity star production, and the effect on the structure of the host galaxy.

  5. GALAXY ROTATION AND RAPID SUPERMASSIVE BINARY COALESCENCE

    International Nuclear Information System (INIS)

    Holley-Bockelmann, Kelly; Khan, Fazeel Mahmood

    2015-01-01

    Galaxy mergers usher the supermassive black hole (SMBH) in each galaxy to the center of the potential, where they form an SMBH binary. The binary orbit shrinks by ejecting stars via three-body scattering, but ample work has shown that in spherical galaxy models, the binary separation stalls after ejecting all the stars in its loss cone—this is the well-known final parsec problem. However, it has been shown that SMBH binaries in non-spherical galactic nuclei harden at a nearly constant rate until reaching the gravitational wave regime. Here we use a suite of direct N-body simulations to follow SMBH binary evolution in both corotating and counterrotating flattened galaxy models. For N > 500 K, we find that the evolution of the SMBH binary is convergent and is independent of the particle number. Rotation in general increases the hardening rate of SMBH binaries even more effectively than galaxy geometry alone. SMBH binary hardening rates are similar for co- and counterrotating galaxies. In the corotating case, the center of mass of the SMBH binary settles into an orbit that is in corotation resonance with the background rotating model, and the coalescence time is roughly a few 100 Myr faster than a non-rotating flattened model. We find that counterrotation drives SMBHs to coalesce on a nearly radial orbit promptly after forming a hard binary. We discuss the implications for gravitational wave astronomy, hypervelocity star production, and the effect on the structure of the host galaxy

  6. Binary mixtures of condensates in generic confining potentials

    Energy Technology Data Exchange (ETDEWEB)

    Facchi, P [Dipartimento di Matematica and MECENAS, Universita di Bari, I-70125 Bari (Italy); Florio, G; Pascazio, S; Pepe, F V, E-mail: Francesco.Pepe@ba.infn.it [INFN, Sezione di Bari, I-70126 Bari (Italy)

    2011-12-16

    We study a binary mixture of Bose-Einstein condensates, confined in a generic potential, in the Thomas-Fermi approximation. We search for the zero-temperature ground state of the system, both in the case of fixed numbers of particles and fixed chemical potentials. For generic potentials, we analyze the transition from mixed to separated ground-state configurations as the inter-species interaction increases. We derive a simple formula that enables one to determine the location of the domain walls. Finally, we find criteria for the energetic stability of separated configurations, depending on the number and the position of the domain walls separating the two species. (paper)

  7. Binary mixtures of condensates in generic confining potentials

    Science.gov (United States)

    Facchi, P.; Florio, G.; Pascazio, S.; Pepe, F. V.

    2011-12-01

    We study a binary mixture of Bose-Einstein condensates, confined in a generic potential, in the Thomas-Fermi approximation. We search for the zero-temperature ground state of the system, both in the case of fixed numbers of particles and fixed chemical potentials. For generic potentials, we analyze the transition from mixed to separated ground-state configurations as the inter-species interaction increases. We derive a simple formula that enables one to determine the location of the domain walls. Finally, we find criteria for the energetic stability of separated configurations, depending on the number and the position of the domain walls separating the two species.

  8. Binary mixtures of condensates in generic confining potentials

    International Nuclear Information System (INIS)

    Facchi, P; Florio, G; Pascazio, S; Pepe, F V

    2011-01-01

    We study a binary mixture of Bose–Einstein condensates, confined in a generic potential, in the Thomas–Fermi approximation. We search for the zero-temperature ground state of the system, both in the case of fixed numbers of particles and fixed chemical potentials. For generic potentials, we analyze the transition from mixed to separated ground-state configurations as the inter-species interaction increases. We derive a simple formula that enables one to determine the location of the domain walls. Finally, we find criteria for the energetic stability of separated configurations, depending on the number and the position of the domain walls separating the two species. (paper)

  9. Numerical modeling of two-phase binary fluid mixing using mixed finite elements

    KAUST Repository

    Sun, Shuyu; Firoozabadi, Abbas; Kou, Jisheng

    2012-01-01

    -phase flow in porous media is established based on Darcy's law, material balance, local thermodynamic equilibrium for the phases, and diffusion across the phases. The time-lag and operator-splitting techniques are used to decompose each convection

  10. Entropic Behavior of Binary Carbonaceous Mesophases

    Directory of Open Access Journals (Sweden)

    Alejandro D. Rey

    2008-08-01

    Full Text Available The Maier-Saupe model for binary mixtures of uniaxial discotic nematogens, formulated in a previous study [1], is used to compute and characterize orientational entropy [2] and orientational specific heat. These thermodynamic quantities are used to determine mixture type (ideal or non-ideal which arise due to their different intrinsic properties, determined by the molecular weight asymmetry ΔMw and the molecular interaction parameter β. These molecular properties are also used to characterize the critical concentration where the mixture behaves like a single component system and exhibits the minimum nematic to isotropic (NI transition temperature (pseudo-pure mixture. A transition within the nematic phase takes place at this specific concentration. According to the Maier-Saupe model, in a single mesogen, entropy at NI transition is a universal value; in this work we quantify the mixing effect on this universal property. The results and analysis provide a new tool to characterize molecular interaction and molecular weight differences in mesogenic mixtures using standard calorimetric measurements.

  11. Activity coefficients of solutes in binary solvents

    International Nuclear Information System (INIS)

    Gokcen, N.A.

    1982-01-01

    The activity coefficients in dilute ternary systems are discussed in detail by using the Margules equations. Analyses of some relevant data at high temperatures show that the sparingly dissolved solutes in binary solvents follow complex behavior even when the binary solvents are very nearly ideal. It is shown that the activity data on the solute or the binary system cannot permit computation of the remaining activities except for the regular solutions. It is also shown that a fourth-order equation is usually adequate in expressing the activity coefficient of a solute in binary solvents at high temperatures. When the activity data for a binary solvent are difficult to obtain in a certain range of composition, the activity data for a sparingly dissolved solute can be used to supplement determination of the binary activities

  12. The Binary System Laboratory Activities Based on Students Mental Model

    Science.gov (United States)

    Albaiti, A.; Liliasari, S.; Sumarna, O.; Martoprawiro, M. A.

    2017-09-01

    Generic science skills (GSS) are required to develop student conception in learning binary system. The aim of this research was to know the improvement of students GSS through the binary system labotoratory activities based on their mental model using hypothetical-deductive learning cycle. It was a mixed methods embedded experimental model research design. This research involved 15 students of a university in Papua, Indonesia. Essay test of 7 items was used to analyze the improvement of students GSS. Each items was designed to interconnect macroscopic, sub-microscopic and symbolic levels. Students worksheet was used to explore students mental model during investigation in laboratory. The increase of students GSS could be seen in their N-Gain of each GSS indicators. The results were then analyzed descriptively. Students mental model and GSS have been improved from this study. They were interconnect macroscopic and symbolic levels to explain binary systems phenomena. Furthermore, they reconstructed their mental model with interconnecting the three levels of representation in Physical Chemistry. It necessary to integrate the Physical Chemistry Laboratory into a Physical Chemistry course for effectiveness and efficiency.

  13. Asteroseismology of KIC 7107778: a binary comprising almost identical subgiants

    Science.gov (United States)

    Li, Yaguang; Bedding, Timothy R.; Li, Tanda; Bi, Shaolan; Murphy, Simon J.; Corsaro, Enrico; Chen, Li; Tian, Zhijia

    2018-05-01

    We analyse an asteroseismic binary system: KIC 7107778, a non-eclipsing, unresolved target, with solar-like oscillations in both components. We used Kepler short cadence time series spanning nearly 2 yr to obtain the power spectrum. Oscillation mode parameters were determined using Bayesian inference and a nested sampling Monte Carlo algorithm with the DIAMONDS package. The power profiles of the two components fully overlap, indicating their close similarity. We modelled the two stars with MESA and calculated oscillation frequencies with GYRE. Stellar fundamental parameters (mass, radius, and age) were estimated by grid modelling with atmospheric parameters and the oscillation frequencies of l = 0, 2 modes as constraints. Most l = 1 mixed modes were identified with models searched using a bisection method. Stellar parameters for the two sub-giant stars are MA = 1.42 ± 0.06 M⊙, MB = 1.39 ± 0.03 M⊙, RA = 2.93 ± 0.05 R⊙, RB = 2.76 ± 0.04 R⊙, tA = 3.32 ± 0.54 Gyr and tB = 3.51 ± 0.33 Gyr. The mass difference of the system is ˜1 per cent. The results confirm their simultaneous birth and evolution, as is expected from binary formation. KIC 7107778 comprises almost identical twins, and is the first asteroseismic sub-giant binary to be detected.

  14. Mixed-ligand complexes of zirconium (IV) and uranium with salicylaldehyde and some heterocyclic azopyrazolones

    International Nuclear Information System (INIS)

    Amrallahi, A.H.

    1994-01-01

    Mixed-ligand complexes of Zr(IV) and U(IV) with salicylaldehyde (SA) and some heterocyclic azopyrazolenes have been studied spectrophotometrically. All formed chelates have ratio 1:1:1. The stoichiometry and stability of the binary mixed chelates been evaluated. Elemental analysis, molar conductance and IR spectra have been used for identification of solid mixed complexes. (author)

  15. Pulsar magnetospheres in binary systems

    Science.gov (United States)

    Ershkovich, A. I.; Dolan, J. F.

    1985-01-01

    The criterion for stability of a tangential discontinuity interface in a magnetized, perfectly conducting inviscid plasma is investigated by deriving the dispersion equation including the effects of both gravitational and centrifugal acceleration. The results are applied to neutron star magnetospheres in X-ray binaries. The Kelvin-Helmholtz instability appears to be important in determining whether MHD waves of large amplitude generated by instability may intermix the plasma effectively, resulting in accretion onto the whole star as suggested by Arons and Lea and leading to no X-ray pulsar behavior.

  16. The structures of binary compounds

    CERN Document Server

    Hafner, J; Jensen, WB; Majewski, JA; Mathis, K; Villars, P; Vogl, P; de Boer, FR

    1990-01-01

    - Up-to-date compilation of the experimental data on the structures of binary compounds by Villars and colleagues. - Coloured structure maps which order the compounds into their respective structural domains and present for the first time the local co-ordination polyhedra for the 150 most frequently occurring structure types, pedagogically very helpful and useful in the search for new materials with a required crystal structure. - Crystal co-ordination formulas: a flexible notation for the interpretation of solid-state structures by chemist Bill Jensen. - Recent important advances in unders

  17. Tomographic reconstruction of binary fields

    International Nuclear Information System (INIS)

    Roux, Stéphane; Leclerc, Hugo; Hild, François

    2012-01-01

    A novel algorithm is proposed for reconstructing binary images from their projection along a set of different orientations. Based on a nonlinear transformation of the projection data, classical back-projection procedures can be used iteratively to converge to the sought image. A multiscale implementation allows for a faster convergence. The algorithm is tested on images up to 1 Mb definition, and an error free reconstruction is achieved with a very limited number of projection data, saving a factor of about 100 on the number of projections required for classical reconstruction algorithms.

  18. Young and Waltzing Binary Stars

    Science.gov (United States)

    2001-10-01

    ADONIS Observes Low-mass Eclipsing System in Orion Summary A series of very detailed images of a binary system of two young stars have been combined into a movie . In merely 3 days, the stars swing around each other. As seen from the earth, they pass in front of each other twice during a full revolution, producing eclipses during which their combined brightness diminishes . A careful analysis of the orbital motions has now made it possible to deduce the masses of the two dancing stars . Both turn out to be about as heavy as our Sun. But while the Sun is about 4500 million years old, these two stars are still in their infancy. They are located some 1500 light-years away in the Orion star-forming region and they probably formed just 10 million years ago . This is the first time such an accurate determination of the stellar masses could be achieved for a young binary system of low-mass stars . The new result provides an important piece of information for our current understanding of how young stars evolve. The observations were obtained by a team of astronomers from Italy and ESO [1] using the ADaptive Optics Near Infrared System (ADONIS) on the 3.6-m telescope at the ESO La Silla Observatory. PR Photo 29a/01 : The RXJ 0529.4+0041 system before primary eclipse PR Photo 29b/01 : The RXJ 0529.4+0041 system at mid-primary eclipse PR Photo 29c/01 : The RXJ 0529.4+0041 system after primary eclipse PR Photo 29d/01 : The RXJ 0529.4+0041 system before secondary eclipse PR Photo 29e/01 : The RXJ 0529.4+0041 system at mid-secondary eclipse PR Photo 29f/01 : The RXJ 0529.4+0041 system after secondary eclipse PR Video Clip 06/01 : Video of the RXJ 0529.4+0041 system Binary stars and stellar masses Since some time, astronomers have noted that most stars seem to form in binary or multiple systems. This is quite fortunate, as the study of binary stars is the only way in which it is possible to measure directly one of the most fundamental quantities of a star, its mass. The mass of a

  19. Microlensing Signature of Binary Black Holes

    Science.gov (United States)

    Schnittman, Jeremy; Sahu, Kailash; Littenberg, Tyson

    2012-01-01

    We calculate the light curves of galactic bulge stars magnified via microlensing by stellar-mass binary black holes along the line-of-sight. We show the sensitivity to measuring various lens parameters for a range of survey cadences and photometric precision. Using public data from the OGLE collaboration, we identify two candidates for massive binary systems, and discuss implications for theories of star formation and binary evolution.

  20. Survival of planets around shrinking stellar binaries.

    Science.gov (United States)

    Muñoz, Diego J; Lai, Dong

    2015-07-28

    The discovery of transiting circumbinary planets by the Kepler mission suggests that planets can form efficiently around binary stars. None of the stellar binaries currently known to host planets has a period shorter than 7 d, despite the large number of eclipsing binaries found in the Kepler target list with periods shorter than a few days. These compact binaries are believed to have evolved from wider orbits into their current configurations via the so-called Lidov-Kozai migration mechanism, in which gravitational perturbations from a distant tertiary companion induce large-amplitude eccentricity oscillations in the binary, followed by orbital decay and circularization due to tidal dissipation in the stars. Here we explore the orbital evolution of planets around binaries undergoing orbital decay by this mechanism. We show that planets may survive and become misaligned from their host binary, or may develop erratic behavior in eccentricity, resulting in their consumption by the stars or ejection from the system as the binary decays. Our results suggest that circumbinary planets around compact binaries could still exist, and we offer predictions as to what their orbital configurations should be like.

  1. Contact Binaries on Their Way Towards Merging

    Science.gov (United States)

    Gazeas, K.

    2015-07-01

    Contact binaries are the most frequently observed type of eclipsing star system. They are small, cool, low-mass binaries belonging to a relatively old stellar population. They follow certain empirical relationships that closely connect a number of physical parameters with each other, largely because of constraints coming from the Roche geometry. As a result, contact binaries provide an excellent test of stellar evolution, specifically for stellar merger scenarios. Observing campaigns by many authors have led to the cataloging of thousands of contact binaries and enabled statistical studies of many of their properties. A large number of contact binaries have been found to exhibit extraordinary behavior, requiring follow-up observations to study their peculiarities in detail. For example, a doubly-eclipsing quadruple system consisting of a contact binary and a detached binary is a highly constrained system offering an excellent laboratory to test evolutionary theories for binaries. A new observing project was initiated at the University of Athens in 2012 in order to investigate the possible lower limit for the orbital period of binary systems before coalescence, prior to merging.

  2. Thermodynamic equilibrium of hydroxyacetic acid in pure and binary solvent systems

    International Nuclear Information System (INIS)

    Huang, Qiaoyin; Xie, Chuang; Li, Yang; Su, Nannan; Lou, Yajing; Hu, Xiaoxue; Wang, Yongli; Bao, Ying; Hou, Baohong

    2017-01-01

    Highlights: • Solubility of hydroxyacetic acid in mono-solvents and binary solvent mixtures was measured. • Modified Apelblat, NRTL and Wilson model were used to correlate the solubility data in pure solvents. • CNIBS/R-K and Jouyban-Acree model were used to correlate the solubility in binary solvent mixtures. • The mixing properties were calculated based on the NRTL model. - Abstract: The solubility of hydroxyacetic acid in five pure organic solvents and two binary solvent mixtures were experimentally measured from 273.15 K to 313.15 K at atmospheric pressure (p = 0.1 MPa) by using a dynamic method. The order of solubility in pure organic solvents is ethanol > isopropanol > n-butanol > acetonitrile > ethyl acetate within the investigated temperature range, except for temperature lower than 278 K where the solubility of HA in ethyl acetate is slightly larger than that in acetonitrile. Furthermore, the solubility data in pure solvents were correlated with the modified Apelblat model, NRTL model, and Wilson model and that in the binary solvents mixtures were fitted to the CNIBS/R-K model and Jouyban-Acree model. Finally, the mixing thermodynamic properties of hydroxyacetic acid in pure and binary solvent systems were calculated and discussed.

  3. Mixing processes in galaxy mergers

    International Nuclear Information System (INIS)

    White, S.D.M.

    1980-01-01

    Previously published simulations of mergers between galaxies are used to examine the degree to which population gradients are weakened during the coalescence of two or more stellar systems. Although substantial mixing occurs during a merger, its effect on such gradients is quite moderate and can be overwhelmed by the effect of changes in structure. Experiment suggests that the centre-to-edge population difference in a merger remnant will be 20 per cent smaller than that in its progenitor galaxies if these are identical centrally concentrated systems. A sequence of three binary mergers is thus required to reduce such differences by a factor of 2. Because of changes in radial structure, population gradients are, in general, reduced more rapidly than is suggested by these numbers. Mixing is more efficient in mergers between less concentrated systems. In real merger remnants any weakening of gradients may often be masked by star-formation in residual interstellar gas. (author)

  4. Mixed parentage

    DEFF Research Database (Denmark)

    Bang Appel, Helene; Singla, Rashmi

    2016-01-01

    Despite an increase in cross border intimate relationships and children of mixed parentage, there is little mention or scholarship about them in the area of childhood and migrancy in the Nordic countries. The international literature implies historical pathologisation, contestation and current...... of identity formation in the . They position themselves as having an “in-between” identity or “ just Danes” in their every day lives among friends, family, and during leisure activities. Thus a new paradigm is evolving away- from the pathologisation of mixed children, simplified one-sided categories...

  5. Fabricating binary optics: An overview of binary optics process technology

    Science.gov (United States)

    Stern, Margaret B.

    1993-01-01

    A review of binary optics processing technology is presented. Pattern replication techniques have been optimized to generate high-quality efficient microoptics in visible and infrared materials. High resolution optical photolithography and precision alignment is used to fabricate maximally efficient fused silica diffractive microlenses at lambda = 633 nm. The degradation in optical efficiency of four-phase-level fused silica microlenses resulting from an intentional 0.35 micron translational error has been systematically measured as a function of lens speed (F/2 - F/60). Novel processes necessary for high sag refractive IR microoptics arrays, including deep anisotropic Si-etching, planarization of deep topography and multilayer resist techniques, are described. Initial results are presented for monolithic integration of photonic and microoptic systems.

  6. Mixed Movements

    DEFF Research Database (Denmark)

    Brabrand, Helle

    2010-01-01

    levels than those related to building, and this exploration is a special challenge and competence implicit artistic development work. The project Mixed Movements generates drawing-material, not primary as representation, but as a performance-based media, making the body being-in-the-media felt and appear...... as possible operational moves....

  7. Lateral Mixing

    Science.gov (United States)

    2014-09-30

    negative (right panel c) and the kinetic energy dissipation is larger than that expected from meterological forcing alone (right panel a). This is...10.1002/grl.50919. Shcherbina, A. et al., 2014, The LatMix Summer Campaign: Submesoscale Stirring in the Upper Ocean., Bull. American Meterological

  8. Application of the Fokker-Planck molecular mixing model to turbulent scalar mixing using moment methods

    Science.gov (United States)

    Madadi-Kandjani, E.; Fox, R. O.; Passalacqua, A.

    2017-06-01

    An extended quadrature method of moments using the β kernel density function (β -EQMOM) is used to approximate solutions to the evolution equation for univariate and bivariate composition probability distribution functions (PDFs) of a passive scalar for binary and ternary mixing. The key element of interest is the molecular mixing term, which is described using the Fokker-Planck (FP) molecular mixing model. The direct numerical simulations (DNSs) of Eswaran and Pope ["Direct numerical simulations of the turbulent mixing of a passive scalar," Phys. Fluids 31, 506 (1988)] and the amplitude mapping closure (AMC) of Pope ["Mapping closures for turbulent mixing and reaction," Theor. Comput. Fluid Dyn. 2, 255 (1991)] are taken as reference solutions to establish the accuracy of the FP model in the case of binary mixing. The DNSs of Juneja and Pope ["A DNS study of turbulent mixing of two passive scalars," Phys. Fluids 8, 2161 (1996)] are used to validate the results obtained for ternary mixing. Simulations are performed with both the conditional scalar dissipation rate (CSDR) proposed by Fox [Computational Methods for Turbulent Reacting Flows (Cambridge University Press, 2003)] and the CSDR from AMC, with the scalar dissipation rate provided as input and obtained from the DNS. Using scalar moments up to fourth order, the ability of the FP model to capture the evolution of the shape of the PDF, important in turbulent mixing problems, is demonstrated. Compared to the widely used assumed β -PDF model [S. S. Girimaji, "Assumed β-pdf model for turbulent mixing: Validation and extension to multiple scalar mixing," Combust. Sci. Technol. 78, 177 (1991)], the β -EQMOM solution to the FP model more accurately describes the initial mixing process with a relatively small increase in computational cost.

  9. High-pressure viscosity measurements for the ethanol plus toluene binary system

    DEFF Research Database (Denmark)

    Zeberg-Mikkelsen, Claus Kjær; Baylaucq, A.; Watson, G.

    2005-01-01

    measured with a classical capillary viscometer (Ubbelohde) with an uncertainty of 1%. A total of 209 experimental measurements have been obtained for this binary system, which reveals a non-monotonic behavior of the viscosity as a function of the composition, with a minimum. The viscosity behavior...... interacting system showing a negative deviation from ideality. The viscosity of this binary system is represented by the Grunberg-Nissan and the Katti-Chaudhri mixing laws with an overall uncertainty of 12% and 8%, respectively. The viscosity of methanol (23 point) has also been measured in order to verify...

  10. Radial Velocities of 41 Kepler Eclipsing Binaries

    Science.gov (United States)

    Matson, Rachel A.; Gies, Douglas R.; Guo, Zhao; Williams, Stephen J.

    2017-12-01

    Eclipsing binaries are vital for directly determining stellar parameters without reliance on models or scaling relations. Spectroscopically derived parameters of detached and semi-detached binaries allow us to determine component masses that can inform theories of stellar and binary evolution. Here we present moderate resolution ground-based spectra of stars in close binary systems with and without (detected) tertiary companions observed by NASA’s Kepler mission and analyzed for eclipse timing variations. We obtain radial velocities and spectroscopic orbits for five single-lined and 35 double-lined systems, and confirm one false positive eclipsing binary. For the double-lined spectroscopic binaries, we also determine individual component masses and examine the mass ratio {M}2/{M}1 distribution, which is dominated by binaries with like-mass pairs and semi-detached classical Algol systems that have undergone mass transfer. Finally, we constrain the mass of the tertiary component for five double-lined binaries with previously detected companions.

  11. BHDD: Primordial black hole binaries code

    Science.gov (United States)

    Kavanagh, Bradley J.; Gaggero, Daniele; Bertone, Gianfranco

    2018-06-01

    BHDD (BlackHolesDarkDress) simulates primordial black hole (PBH) binaries that are clothed in dark matter (DM) halos. The software uses N-body simulations and analytical estimates to follow the evolution of PBH binaries formed in the early Universe.

  12. Main Memory Implementations for Binary Grouping

    OpenAIRE

    May, Norman; Moerkotte, Guido

    2005-01-01

    An increasing number of applications depend on efficient storage and analysis features for XML data. Hence, query optimization and efficient evaluation techniques for the emerging XQuery standard become more and more important. Many XQuery queries require nested expressions. Unnesting them often introduces binary grouping. We introduce several algorithms implementing binary grouping and analyze their time and space complexity. Experiments demonstrate their performance.

  13. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    objective probabilities. Drawing a sample from the same subject population, we find evidence that the binary lottery procedure induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation...

  14. Bondi-Hoyle-Lyttleton Accretion onto Binaries

    Science.gov (United States)

    Antoni, Andrea; MacLeod, Morgan; Ramírez-Ruiz, Enrico

    2018-01-01

    Binary stars are not rare. While only close binary stars will eventually interact with one another, even the widest binary systems interact with their gaseous surroundings. The rates of accretion and the gaseous drag forces arising in these interactions are the key to understanding how these systems evolve. This poster examines accretion flows around a binary system moving supersonically through a background gas. We perform three-dimensional hydrodynamic simulations of Bondi-Hoyle-Lyttleton accretion using the adaptive mesh refinement code FLASH. We simulate a range of values of semi-major axis of the orbit relative to the gravitational focusing impact parameter of the pair. On large scales, gas is gravitationally focused by the center-of-mass of the binary, leading to dynamical friction drag and to the accretion of mass and momentum. On smaller scales, the orbital motion imprints itself on the gas. Notably, the magnitude and direction of the forces acting on the binary inherit this orbital dependence. The long-term evolution of the binary is determined by the timescales for accretion, slow down of the center-of-mass, and decay of the orbit. We use our simulations to measure these timescales and to establish a hierarchy between them. In general, our simulations indicate that binaries moving through gaseous media will slow down before the orbit decays.

  15. Binary Relations as a Foundation of Mathematics

    NARCIS (Netherlands)

    Kuper, Jan; Barendsen, E.; Capretta, V.; Geuvers, H.; Niqui, M.

    2007-01-01

    We describe a theory for binary relations in the Zermelo-Fraenkel style. We choose for ZFCU, a variant of ZFC Set theory in which the Axiom of Foundation is replaced by an axiom allowing for non-wellfounded sets. The theory of binary relations is shown to be equi-consistent ZFCU by constructing a

  16. RELATIONSHIP BETWEEN FLASH POINTS OF SOME BINARY ...

    African Journals Online (AJOL)

    B. S. Chandravanshi

    Miscellaneous binary blends containing solvent neutral-150 (SN-150), ... viscosity, the flash point test has always been a standard part of a lubricant's specification. ... between structure and flash points of organic compounds [5-12] and fuels [13, 14]. ... in binary mixtures, the gaps between flash points would be high enough.

  17. The origin of the RS CVn binaries

    International Nuclear Information System (INIS)

    Biermann, P.

    1976-01-01

    Six possible origins for the RS CVn binaries are considered based on the following possibilities. RS CVn binaries might now be either pre-main-sequence or post-main-sequence. A pre-main-sequence binary might not always have been a binary but might have resulted from fission of a rapidly rotating single pre-main-sequence star. The main-sequence counterparts might be either single stars or binaries. To decide which of the six origins is possible, the following observed data for the RS CVn binaries are considered: total mass, total angular momentum, lack of observed connection with regions of star formation, large space density, kinematical age, and the visual companion of WW Dra. In addition lifetimes and space densities of single stars and other types of binaries are considered. The only origin possible is that the RS CVn binaries are in a thermal phase following fission of a main-sequence single star. In this explanation the single star had a rapidly rotating core which became unstable due to the core contraction which made it begin to evolve off the main sequence. The present Be stars might be examples of such parent single stars. (Auth.)

  18. Mass Transfer in Mira-Type Binaries

    Directory of Open Access Journals (Sweden)

    Mohamed S.

    2012-06-01

    Full Text Available Detached, symbiotic binaries are generally assumed to interact via Bondi-Hoyle-Littleton (BHL wind accretion. However, the accretion rates and outflow geometries that result from this mass-transfer mechanism cannot adequately explain the observations of the nearest and best studied symbiotic binary, Mira, or the formation of some post-AGB binaries, e.g. barium stars. We propose a new mass-transfer mode for Mira-type binaries, which we call ‘wind Roche-lobe overflow’ (WRLOF, and which we demonstrate with 3D hydrodynamic simulations. Importantly, we show that the circumstellar outflows which result from WRLOF tend to be highly aspherical and strongly focused towards the binary orbital plane. Furthermore, the subsequent mass-transfer rates are at least an order of magnitude greater than the analogous BHL values. We discuss the implications of these results for the shaping of bipolar (proto-planetary nebulae and other related systems.

  19. Logistic chaotic maps for binary numbers generations

    International Nuclear Information System (INIS)

    Kanso, Ali; Smaoui, Nejib

    2009-01-01

    Two pseudorandom binary sequence generators, based on logistic chaotic maps intended for stream cipher applications, are proposed. The first is based on a single one-dimensional logistic map which exhibits random, noise-like properties at given certain parameter values, and the second is based on a combination of two logistic maps. The encryption step proposed in both algorithms consists of a simple bitwise XOR operation of the plaintext binary sequence with the keystream binary sequence to produce the ciphertext binary sequence. A threshold function is applied to convert the floating-point iterates into binary form. Experimental results show that the produced sequences possess high linear complexity and very good statistical properties. The systems are put forward for security evaluation by the cryptographic committees.

  20. Phonons in fcc binary alloys

    International Nuclear Information System (INIS)

    Sharma, Amita; Rathore, R.P.S.

    1992-01-01

    Born-Mayer potential has been modified to account for the unpaired (three body) forces among the common nearest neighbours of the ordered binary fcc alloys i.e. Ni 3 Fe 7 , Ni 5 Fe 5 and Ni 75 Fe 25 . The three body potential is added to the two body form of Morse to formalize the total interaction potential. Measured inverse ionic compressibility, cohesive energy, lattice constant and one measured phonon frequency are used to evaluate the defining parameters of the potential. The potential seeks to bring about the binding among 140 and 132 atoms though pair wise (two body) and non-pair wise (three body) forces respectively. The phonon-dispersion relations obtained by solving the secular equation are compared with the experimental findings on the aforesaid alloys. (author). 19 refs., 3 figs

  1. Parity mixing

    International Nuclear Information System (INIS)

    Adelberger, E.G.

    1975-01-01

    The field of parity mixing in light nuclei bears upon one of the exciting and active problems of physics--the nature of the fundamental weak interaction. It is also a subject where polarization techniques play a very important role. Weak interaction theory is first reviewed to motivate the parity mixing experiments. Two very attractive systems are discussed where the nuclear physics is so beautifully simple that the experimental observation of tiny effects directly measures parity violating (PV) nuclear matrix elements which are quite sensitive to the form of the basic weak interaction. Since the measurement of very small analyzing powers and polarizations may be of general interest to this conference, some discussion is devoted to experimental techniques

  2. Study on preparation and thermal property of binary fatty acid and the binary fatty acids/diatomite composite phase change materials

    International Nuclear Information System (INIS)

    Li, Min; Kao, Hongtao; Wu, Zhishen; Tan, Jinmiao

    2011-01-01

    This study prepared a series of binary phase change materials by mixing decanoic acid, dodecanoic acid, hexadecanoic acid and octadecanoic acid each other. The phase-transition temperature of binary fatty acid and its corresponding mixing proportion are calculated with phase diagram thermodynamic method. The results are verified by the experimental result of the heat absorption curve and the Differential Scanning Calorimetry (DSC) analysis curve. The results show that the calculation method of phase diagram thermodynamic calculation can be taken as a basis for mixing proportion of binary fatty acid phase change materials. In addition, the decanoic-dodecanoic acid/diatomite composite phase change material (PCM) are prepared and its microstructure, thermal property and thermal reliability are characterized. The result shows that the decanoic-dodecanoic acid is uniformly adsorbed into diatomite and the form-stable PCM are formed. The phase-transition temperature and the latent heat of the decanoic-dodecanoic acid/diatomite composite PCMs is 16.74 o C and 66.8114 J/g, respectively.

  3. PERIODIC SIGNALS IN BINARY MICROLENSING EVENTS

    International Nuclear Information System (INIS)

    Guo, Xinyi; Stefano, Rosanne Di; Esin, Ann; Taylor, Jeffrey

    2015-01-01

    Gravitational microlensing events are powerful tools for the study of stellar populations. In particular, they can be used to discover and study a variety of binary systems. A large number of binary lenses have already been found through microlensing surveys and a few of these systems show strong evidence of orbital motion on the timescale of the lensing event. We expect that more binary lenses of this kind will be detected in the future. For binaries whose orbital period is comparable to the event duration, the orbital motion can cause the lensing signal to deviate drastically from that of a static binary lens. The most striking property of such light curves is the presence of quasi-periodic features, which are produced as the source traverses the same regions in the rotating lens plane. These repeating features contain information about the orbital period of the lens. If this period can be extracted, then much can be learned about the lensing system even without performing time-consuming, detailed light-curve modeling. However, the relative transverse motion between the source and the lens significantly complicates the problem of period extraction. To resolve this difficulty, we present a modification of the standard Lomb–Scargle periodogram analysis. We test our method for four representative binary lens systems and demonstrate its efficiency in correctly extracting binary orbital periods

  4. Topological and categorical properties of binary trees

    Directory of Open Access Journals (Sweden)

    H. Pajoohesh

    2008-04-01

    Full Text Available Binary trees are very useful tools in computer science for estimating the running time of so-called comparison based algorithms, algorithms in which every action is ultimately based on a prior comparison between two elements. For two given algorithms A and B where the decision tree of A is more balanced than that of B, it is known that the average and worst case times of A will be better than those of B, i.e., ₸A(n ≤₸B(n and TWA (n≤TWB (n. Thus the most balanced and the most imbalanced binary trees play a main role. Here we consider them as semilattices and characterize the most balanced and the most imbalanced binary trees by topological and categorical properties. Also we define the composition of binary trees as a commutative binary operation, *, such that for binary trees A and B, A * B is the binary tree obtained by attaching a copy of B to any leaf of A. We show that (T,* is a commutative po-monoid and investigate its properties.

  5. Avaliação do desempenho de surfactantes para a solubilização de fases líquidas não aquosas em meio aquoso Evaluating surfactant performance as solubilizer of non-aqueous phase liquids within aqueous media

    Directory of Open Access Journals (Sweden)

    Elizabeth Fátima de Souza

    2010-01-01

    Full Text Available The presence of non-aqueous phase liquids (NAPLs in the subsurface is a threat to public health as well as a serious environmental issue. NAPLs may remain adsorbed or form lenses floating on aquifers causing long-term contaminations. Surfactants may increase NAPLs solubility, enhancing the pump-and-treatment performance. Size, shape, hydration and ionization degree of the micelles define the affinity and the space available for the solubilization of a particular contaminating agent. The tests carried out at laboratory scale, taking into account the NAPL to be removed and the medium characteristics were useful to select surfactants and evaluate their efficiency as NAPLs solubilizers.

  6. Theoretical studies of binaries in astrophysics

    Science.gov (United States)

    Dischler, Johann Sebastian

    This thesis introduces and summarizes four papers dealing with computer simulations of astrophysical processes involving binaries. The first part gives the rational and theoretical background to these papers. In paper I and II a statistical approach to studying eclipsing binaries is described. By using population synthesis models for binaries the probabilities for eclipses are calculated for different luminosity classes of binaries. These are compared with Hipparcos data and they agree well if one uses a standard input distribution for the orbit sizes. If one uses a random pairing model, where both companions are independently picked from an IMF, one finds too feclipsing binaries by an order of magnitude. In paper III we investigate a possible scenario for the origin of the stars observed close to the centre of our galaxy, called S stars. We propose that a cluster falls radially cowards the central black hole. The binaries within the cluster can then, if they have small impact parameters, be broken up by the black hole's tidal held and one of the components of the binary will be captured by the black hole. Paper IV investigates how the onset of mass transfer in eccentric binaries depends on the eccentricity. To do this we have developed a new two-phase SPH scheme where very light particles are at tire outer edge of our simulated star. This enables us to get a much better resolution of the very small mass that is transferred in close binaries. Our simulations show that the minimum required distance between the stars to have mass transfer decreases with the eccentricity.

  7. On the optimity of separation cascade for a binary and a multi-component case

    International Nuclear Information System (INIS)

    Song, T.M.; Zeng, S.

    2006-01-01

    The optimity discussed in this article means minimum total interstage flow which is studied for two cases, a binary and a multi-component case, using direct numerical optimizations for countercurrent symmetric cascades with the concentrations of the target component specified in the .feed flow, the product and waste withdrawals In binary separation, the ideal cascade in which there are no mixing losses and whose stages are working under symmetric separation is the optimum cascade that has the minimum total flow However when the separation factor is large, there may not exist an ideal cascade for certain prescribed external parameters. Cascades are optimized numerically to minimize mixing losses and total flows, respectively The results are compared for the minimum mixing losses and the minimum total flow, and analyzed with theoretically derived formulas. For the multi-component case, satisfying the non-mixing condition is impossible. There is a counterpart of the binary ideal cascade named MARC which matches the abundance ratio at mixing points. An optimization example for a four-cornponent mixture separation cascade is analyzed with the first and the last components as the targets, respectively. The results show that MARC is not the optimum cascade for the separation of one certain isotope. The separation power of each stage in the optimized cascades is calculated using several different definitions, and the rationality of these definitions is discussed. The Q-iteration method is used to calculate the concentration distribution in both the binary and the multi-component cases. Ns-2 stage cuts out of the Ns stages of the cascade are the optimization variables in the optimization process and a combination of the simulated annealing and the Hooke-Jeeves method is applied as the optimization technique to find the minimum. (authors)

  8. Binary neutron star merger simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bruegmann, Bernd [Jena Univ. (Germany)

    2016-11-01

    Our research focuses on the numerical tools necessary to solve Einstein's equations. In recent years we have been particularly interested in spacetimes consisting of two neutron stars in the final stages of their evolution. Because of the emission of gravitational radiation, the objects are driven together to merge; the emitted gravitational wave signal is visualized. This emitted gravitational radiation carries energy and momentum away from the system and contains information about the system. Late last year the Laser Interferometer Gravitational-wave Observatory (LIGO) began searches for these gravitational wave signals at a sensitivity at which detections are expected. Although such systems can radiate a significant amount of their total mass-energy in gravitational waves, the gravitational wave signals one expects to receive on Earth are not strong, since sources of gravitational waves are often many millions of light years away. Therefore one needs accurate templates for the radiation one expects from such systems in order to be able to extract them out of the detector's noise. Although analytical models exist for compact binary systems when the constituents are well separated, we need numerical simulation to investigate the last orbits before merger to obtain accurate templates and validate analytical approximations. Due to the strong nonlinearity of the equations and the large separation of length scales, these simulations are computationally demanding and need to be run on large supercomputers. When matter is present the computational cost as compared to pure black hole (vacuum) simulations increases even more due to the additional matter fields. But also more interesting astrophysical phenomena can happen. In fact, there is the possibility for a strong electromagnetic signal from the merger (e.g., a short gamma-ray burst or lower-energy electromagnetic signatures from the ejecta) and significant neutrino emission. Additionally, we can expect that

  9. Instabilities in Interacting Binary Stars

    Science.gov (United States)

    Andronov, I. L.; Andrych, K. D.; Antoniuk, K. A.; Baklanov, A. V.; Beringer, P.; Breus, V. V.; Burwitz, V.; Chinarova, L. L.; Chochol, D.; Cook, L. M.; Cook, M.; Dubovský, P.; Godlowski, W.; Hegedüs, T.; Hoňková, K.; Hric, L.; Jeon, Y.-B.; Juryšek, J.; Kim, C.-H.; Kim, Y.; Kim, Y.-H.; Kolesnikov, S. V.; Kudashkina, L. S.; Kusakin, A. V.; Marsakova, V. I.; Mason, P. A.; Mašek, M.; Mishevskiy, N.; Nelson, R. H.; Oksanen, A.; Parimucha, S.; Park, J.-W.; Petrík, K.; Quiñones, C.; Reinsch, K.; Robertson, J. W.; Sergey, I. M.; Szpanko, M.; Tkachenko, M. G.; Tkachuk, L. G.; Traulsen, I.; Tremko, J.; Tsehmeystrenko, V. S.; Yoon, J.-N.; Zola, S.; Shakhovskoy, N. M.

    2017-07-01

    The types of instability in the interacting binary stars are briefly reviewed. The project “Inter-Longitude Astronomy” is a series of smaller projects on concrete stars or groups of stars. It has no special funds, and is supported from resources and grants of participating organizations, when informal working groups are created. This “ILA” project is in some kind similar and complementary to other projects like WET, CBA, UkrVO, VSOLJ, BRNO, MEDUZA, AstroStatistics, where many of us collaborate. Totally we studied 1900+ variable stars of different types, including newly discovered variables. The characteristic timescale is from seconds to decades and (extrapolating) even more. The monitoring of the first star of our sample AM Her was initiated by Prof. V.P. Tsesevich (1907-1983). Since more than 358 ADS papers were published. In this short review, we present some highlights of our photometric and photo-polarimetric monitoring and mathematical modeling of interacting binary stars of different types: classical (AM Her, QQ Vul, V808 Aur = CSS 081231:071126+440405, FL Cet), asynchronous (BY Cam, V1432 Aql), intermediate (V405 Aql, BG CMi, MU Cam, V1343 Her, FO Aqr, AO Psc, RXJ 2123, 2133, 0636, 0704) polars and magnetic dwarf novae (DO Dra) with 25 timescales corresponding to different physical mechanisms and their combinations (part “Polar”); negative and positive superhumpers in nova-like (TT Ari, MV Lyr, V603 Aql, V795 Her) and many dwarf novae stars (“Superhumper”); eclipsing “non-magnetic” cataclysmic variables(BH Lyn, DW UMa, EM Cyg; PX And); symbiotic systems (“Symbiosis”); super-soft sources (SSS, QR And); spotted (and not spotted) eclipsing variables with (and without) evidence for a current mass transfer (“Eclipser”) with a special emphasis on systems with a direct impact of the stream into the gainer star's atmosphere, which we propose to call “Impactor” (short from “Extreme Direct Impactor”), or V361 Lyr-type stars. Other

  10. Variance in binary stellar population synthesis

    Science.gov (United States)

    Breivik, Katelyn; Larson, Shane L.

    2016-03-01

    In the years preceding LISA, Milky Way compact binary population simulations can be used to inform the science capabilities of the mission. Galactic population simulation efforts generally focus on high fidelity models that require extensive computational power to produce a single simulated population for each model. Each simulated population represents an incomplete sample of the functions governing compact binary evolution, thus introducing variance from one simulation to another. We present a rapid Monte Carlo population simulation technique that can simulate thousands of populations in less than a week, thus allowing a full exploration of the variance associated with a binary stellar evolution model.

  11. Proposed experiment to test fundamentally binary theories

    Science.gov (United States)

    Kleinmann, Matthias; Vértesi, Tamás; Cabello, Adán

    2017-09-01

    Fundamentally binary theories are nonsignaling theories in which measurements of many outcomes are constructed by selecting from binary measurements. They constitute a sensible alternative to quantum theory and have never been directly falsified by any experiment. Here we show that fundamentally binary theories are experimentally testable with current technology. For that, we identify a feasible Bell-type experiment on pairs of entangled qutrits. In addition, we prove that, for any n , quantum n -ary correlations are not fundamentally (n -1 ) -ary. For that, we introduce a family of inequalities that hold for fundamentally (n -1 ) -ary theories but are violated by quantum n -ary correlations.

  12. Galactic binaries with eLISA

    OpenAIRE

    Nelemans, G.

    2013-01-01

    I review what eLISA will see from Galactic binaries -- double stars with orbital periods less than a few hours and white dwarf (or neutron star/black hole) components. I discuss the currently known binaries that are guaranteed (or verification) sources and explain why the expected total number of eLISA Galactic binaries is several thousand, even though there are large uncertainties in our knowledge of this population, in particular that of the interacting AM CVn systems. I very briefly sketch...

  13. Dixie Valley Bottoming Binary Unit

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Dale [Terra-Gen Sierra Holdings, LLC, Reno, NV (United States)

    2014-12-21

    This binary plant is the first air cooled, high-output refrigeration based waste heat recovery cycle in the industry. Its working fluid is environmentally friendly and as such, the permits that would be required with a hydrocarbon based cycle are not necessary. The unit is largely modularized, meaning that the unit’s individual skids were assembled in another location and were shipped via truck to the plant site. The Air Cooled Condensers (ACC), equipment piping, and Balance of Plant (BOP) piping were constructed at site. This project further demonstrates the technical feasibility of using low temperature brine for geothermal power utilization. The development of the unit led to the realization of low temperature, high output, and environmentally friendly heat recovery systems through domestic research and engineering. The project generates additional renewable energy, resulting in cleaner air and reduced carbon dioxide emissions. Royalty and tax payments to governmental agencies will increase, resulting in reduced financial pressure on local entities. The major components of the unit were sourced from American companies, resulting in increased economic activity throughout the country.

  14. The symbiotics as binary stars

    International Nuclear Information System (INIS)

    Plavec, M.J.

    1982-01-01

    The author envisages at least three models that can give a symbiotic object: He has called them, respectively, the PN symbiotic, the Algol symbiotic, and the novalike symbiotic. Their properties are briefly discussed. The most promising model is one of a binary system in the second stage of mass transfer, actually at the beginning of it: The cool component is a red giant ascending the asymptotic branch, expanding but not yet filling its critical lobe. The hot star is a subdwarf located in the same region of the Hertzsprung-Russell diagram as the central stars of planetary nebulae. It may be closely related to them, or it may be a helium star, actually a remnant of an Algol primary which underwent the first stage of mass transfer. In these cases, accretion on this star may not play a significant role (PN symbiotic). Perhaps more often, the subdwarf is a ''rejuvenated'' degenerate dwarf whose nuclear burning shells were ignited and are maintained by accretion of material coming from the red giant in the form of a stellar wind. Eruptions are often inevitable: this is the novalike symbiotic. A third alternative is a system in the first stage of mass transfer, where the photons needed for ionization of the nebula come from an accretion disk surrounding a main sequence star: an Algol symbiotic. In spite of considerable observational effort, the symbiotics are known so poorly that it is hard to decide between the models, or even decide if all three can actually exist. (Auth.)

  15. Pulsars in binary systems: probing binary stellar evolution and general relativity.

    Science.gov (United States)

    Stairs, Ingrid H

    2004-04-23

    Radio pulsars in binary orbits often have short millisecond spin periods as a result of mass transfer from their companion stars. They therefore act as very precise, stable, moving clocks that allow us to investigate a large set of otherwise inaccessible astrophysical problems. The orbital parameters derived from high-precision binary pulsar timing provide constraints on binary evolution, characteristics of the binary pulsar population, and the masses of neutron stars with different mass-transfer histories. These binary systems also test gravitational theories, setting strong limits on deviations from general relativity. Surveys for new pulsars yield new binary systems that increase our understanding of all these fields and may open up whole new areas of physics, as most spectacularly evidenced by the recent discovery of an extremely relativistic double-pulsar system.

  16. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. II. P-TYPE BINARIES

    International Nuclear Information System (INIS)

    Haghighipour, Nader; Kaltenegger, Lisa

    2013-01-01

    We have developed a comprehensive methodology for calculating the circumbinary habitable zone (HZ) in planet-hosting P-type binary star systems. We present a general formalism for determining the contribution of each star of the binary to the total flux received at the top of the atmosphere of an Earth-like planet and use the Sun's HZ to calculate the inner and outer boundaries of the HZ around a binary star system. We apply our calculations to the Kepler's currently known circumbinary planetary systems and show the combined stellar flux that determines the boundaries of their HZs. We also show that the HZ in P-type systems is dynamic and, depending on the luminosity of the binary stars, their spectral types, and the binary eccentricity, its boundaries vary as the stars of the binary undergo their orbital motion. We present the details of our calculations and discuss the implications of the results

  17. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. II. P-TYPE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Haghighipour, Nader [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii-Manoa, Honolulu, HI 96822 (United States); Kaltenegger, Lisa [MPIA, Koenigstuhl 17, Heidelberg, D-69117 (Germany)

    2013-11-10

    We have developed a comprehensive methodology for calculating the circumbinary habitable zone (HZ) in planet-hosting P-type binary star systems. We present a general formalism for determining the contribution of each star of the binary to the total flux received at the top of the atmosphere of an Earth-like planet and use the Sun's HZ to calculate the inner and outer boundaries of the HZ around a binary star system. We apply our calculations to the Kepler's currently known circumbinary planetary systems and show the combined stellar flux that determines the boundaries of their HZs. We also show that the HZ in P-type systems is dynamic and, depending on the luminosity of the binary stars, their spectral types, and the binary eccentricity, its boundaries vary as the stars of the binary undergo their orbital motion. We present the details of our calculations and discuss the implications of the results.

  18. Computation of infinite dilute activity coefficients of binary liquid alloys using complex formation model

    Energy Technology Data Exchange (ETDEWEB)

    Awe, O.E., E-mail: draweoe2004@yahoo.com; Oshakuade, O.M.

    2016-04-15

    A new method for calculating Infinite Dilute Activity Coefficients (γ{sup ∞}s) of binary liquid alloys has been developed. This method is basically computing γ{sup ∞}s from experimental thermodynamic integral free energy of mixing data using Complex formation model. The new method was first used to theoretically compute the γ{sup ∞}s of 10 binary alloys whose γ{sup ∞}s have been determined by experiments. The significant agreement between the computed values and the available experimental values served as impetus for applying the new method to 22 selected binary liquid alloys whose γ{sup ∞}s are either nonexistent or incomplete. In order to verify the reliability of the computed γ{sup ∞}s of the 22 selected alloys, we recomputed the γ{sup ∞}s using three other existing methods of computing or estimating γ{sup ∞}s and then used the γ{sup ∞}s obtained from each of the four methods (the new method inclusive) to compute thermodynamic activities of components of each of the binary systems. The computed activities were compared with available experimental activities. It is observed that the results from the method being proposed, in most of the selected alloys, showed better agreement with experimental activity data. Thus, the new method is an alternative and in certain instances, more reliable approach of computing γ{sup ∞}s of binary liquid alloys.

  19. Measurement and correlation of solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures

    International Nuclear Information System (INIS)

    Wang, Jinxiu; Xie, Chuang; Yin, Qiuxiang; Tao, Linggang; Lv, Jun; Wang, Yongli; He, Fang; Hao, Hongxun

    2016-01-01

    Highlights: • Solubility of cefmenoxime hydrochloride in pure and binary solvents was determined. • The experimental solubility data were correlated by thermodynamic models. • A model was employed to calculate the melting temperature of cefmenoxime hydrochloride. • Mixing thermodynamic properties of cefmenoxime hydrochloride were calculated. - Abstract: The solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures was measured at temperatures from (283.15 to 313.15) K by using the UV spectroscopic method. The results reveal that the solubility of cefmenoxime hydrochloride increases with increasing temperature in all solvent selected. The solubility of cefmenoxime hydrochloride reaches its maximum value when the mole fraction of isopropanol is 0.2 in the binary solvent mixtures of (isopropanol + water). The modified Apelblat equation and the NRTL model were successfully used to correlate the experimental solubility in pure solvents while the modified Apelblat equation, the CNIBS/R–K model and the Jouyban–Acree model were applied to correlate the solubility in binary solvent mixtures. In addition, the mixing thermodynamic properties of cefmenoxime hydrochloride in different solvents were also calculated based on the NRTL model and experimental solubility data.

  20. General simulation algorithm for autocorrelated binary processes.

    Science.gov (United States)

    Serinaldi, Francesco; Lombardo, Federico

    2017-02-01

    The apparent ubiquity of binary random processes in physics and many other fields has attracted considerable attention from the modeling community. However, generation of binary sequences with prescribed autocorrelation is a challenging task owing to the discrete nature of the marginal distributions, which makes the application of classical spectral techniques problematic. We show that such methods can effectively be used if we focus on the parent continuous process of beta distributed transition probabilities rather than on the target binary process. This change of paradigm results in a simulation procedure effectively embedding a spectrum-based iterative amplitude-adjusted Fourier transform method devised for continuous processes. The proposed algorithm is fully general, requires minimal assumptions, and can easily simulate binary signals with power-law and exponentially decaying autocorrelation functions corresponding, for instance, to Hurst-Kolmogorov and Markov processes. An application to rainfall intermittency shows that the proposed algorithm can also simulate surrogate data preserving the empirical autocorrelation.

  1. General simulation algorithm for autocorrelated binary processes

    Science.gov (United States)

    Serinaldi, Francesco; Lombardo, Federico

    2017-02-01

    The apparent ubiquity of binary random processes in physics and many other fields has attracted considerable attention from the modeling community. However, generation of binary sequences with prescribed autocorrelation is a challenging task owing to the discrete nature of the marginal distributions, which makes the application of classical spectral techniques problematic. We show that such methods can effectively be used if we focus on the parent continuous process of beta distributed transition probabilities rather than on the target binary process. This change of paradigm results in a simulation procedure effectively embedding a spectrum-based iterative amplitude-adjusted Fourier transform method devised for continuous processes. The proposed algorithm is fully general, requires minimal assumptions, and can easily simulate binary signals with power-law and exponentially decaying autocorrelation functions corresponding, for instance, to Hurst-Kolmogorov and Markov processes. An application to rainfall intermittency shows that the proposed algorithm can also simulate surrogate data preserving the empirical autocorrelation.

  2. Observations of new Wolf-Rayet binaries

    International Nuclear Information System (INIS)

    Niemela, V.S.

    1982-01-01

    The author reports here preliminary results of spectrographic observations for three southern WR stars, whose binary nature had not been previously verified: HDE 320102, CD -45 0 4482, HD 62910. The observations were carried out at the Cerro Tololo Inter-American Observatory, Chile, mostly with the Cassegrain spectrograph with IT attached to the 1-m reflector. These spectrograms were secured on Kodak IIIaJ emulsion, and have a dispersion of 45 A/mm. The results suggest that HDE 320102 must be a double-lined 05-7 + WN3 spectroscopic binary, that CD -45 0 4482 appears to be a single-lined spectroscopic binary and that HD 62910 may be a binary. (Auth.)

  3. Carbon-enhanced metal-poor stars and thermohaline mixing

    NARCIS (Netherlands)

    Stancliffe, R.J.; Glebbeek, E.; Izzard, R.G.; Pols, O.R.

    2007-01-01

    One possible scenario for the formation of carbon-enhanced metal-poor stars is the accretion of carbon-rich material from a binary companion which may no longer visible. It is generally assumed that the accreted material remains on the surface of the star and does not mix with the interior until

  4. Thorium/uranium mixed oxide nano-crystals: Synthesis, structural characterization and magnetic properties

    International Nuclear Information System (INIS)

    Hudry, Damien; Griveau, Jean-Christophe; Apostolidis, Christos; Colineau, Eric; Rasmussen, Gert; Walter, Olaf; Wang, Di; Venkata Sai Kiran Chakravadhaluna; Courtois, Eglantine; Kubel, Christian

    2014-01-01

    One of the primary aims of the actinide community within nano-science is to develop a good understanding similar to what is currently the case for stable elements. As a consequence, efficient, reliable and versatile synthesis techniques dedicated to the formation of new actinide-based nano-objects (e.g., nano-crystals) are necessary. Hence, a 'library' dedicated to the preparation of various actinide based nano-scale building blocks is currently being developed. Nano-scale building blocks with tunable sizes, shapes and compositions are of prime importance. So far, the non-aqueous synthesis method in highly coordinating organic media is the only approach which has demonstrated the capability to provide size and shape control of actinide-based nano-crystals (both for thorium and uranium, and recently extended to neptunium and plutonium). In this paper, we demonstrate that the non-aqueous approach is also well adapted to control the chemical composition of the nano-crystals obtained when mixing two different actinides. Indeed, the controlled hot co-injection of thorium acetylacetonate and uranyl acetate (together with additional capping agents) into benzyl ether can be used to synthesize thorium/uranium mixed oxide nano-crystals covering the full compositional spectrum. Additionally, we found that both size and shape are modified as a function of the thorium/uranium ratio. Finally, the magnetic properties of the different thorium/uranium mixed oxide nano-crystals were investigated. Contrary to several reports, we did not observe any ferromagnetic behavior. As a consequence, ferromagnetism cannot be described as a universal feature of nano-crystals of non-magnetic oxides as recently claimed in the literature. (authors)

  5. Diffusion in ordered binary solid systems

    International Nuclear Information System (INIS)

    Stolwijk, N.A.

    1980-01-01

    This thesis contains contributions to the field of diffusion in ordered binary solid systems. An extensive experimental investigation of the self diffusion in CoGa is presented. The results of these diffusion measurements strongly suggest that a substantial part of the atomic migration is caused by a new type of defect. A quantitative description of the atomic displacements via this defect is given. Finally computer simulations are presented of diffusion and ordering in binary solid systems. (Auth.)

  6. An Introduction to Binary Decision Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif

    1996-01-01

    This note is a short introduction to Binary Decision Diagrams (BDDs). It provides some background knowledge and describes the core algorithms. It is used in the course "C4340 Advanced Algorithms" at the Technical University of Denmark, autumn 1996.......This note is a short introduction to Binary Decision Diagrams (BDDs). It provides some background knowledge and describes the core algorithms. It is used in the course "C4340 Advanced Algorithms" at the Technical University of Denmark, autumn 1996....

  7. Asteroseismic effects in close binary stars

    Science.gov (United States)

    Springer, Ofer M.; Shaviv, Nir J.

    2013-09-01

    Turbulent processes in the convective envelopes of the Sun and stars have been shown to be a source of internal acoustic excitations. In single stars, acoustic waves having frequencies below a certain cut-off frequency propagate nearly adiabatically and are effectively trapped below the photosphere where they are internally reflected. This reflection essentially occurs where the local wavelength becomes comparable to the pressure scale height. In close binary stars, the sound speed is a constant on equipotentials, while the pressure scale height, which depends on the local effective gravity, varies on equipotentials and may be much greater near the inner Lagrangian point (L1). As a result, waves reaching the vicinity of L1 may propagate unimpeded into low-density regions, where they tend to dissipate quickly due to non-linear and radiative effects. We study the three-dimensional propagation and enhanced damping of such waves inside a set of close binary stellar models using a WKB approximation of the acoustic field. We find that these waves can have much higher damping rates in close binaries, compared to their non-binary counterparts. We also find that the relative distribution of acoustic energy density at the visible surface of close binaries develops a ring-like feature at specific acoustic frequencies and binary separations.

  8. Texture classification by texton: statistical versus binary.

    Directory of Open Access Journals (Sweden)

    Zhenhua Guo

    Full Text Available Using statistical textons for texture classification has shown great success recently. The maximal response 8 (Statistical_MR8, image patch (Statistical_Joint and locally invariant fractal (Statistical_Fractal are typical statistical texton algorithms and state-of-the-art texture classification methods. However, there are two limitations when using these methods. First, it needs a training stage to build a texton library, thus the recognition accuracy will be highly depended on the training samples; second, during feature extraction, local feature is assigned to a texton by searching for the nearest texton in the whole library, which is time consuming when the library size is big and the dimension of feature is high. To address the above two issues, in this paper, three binary texton counterpart methods were proposed, Binary_MR8, Binary_Joint, and Binary_Fractal. These methods do not require any training step but encode local feature into binary representation directly. The experimental results on the CUReT, UIUC and KTH-TIPS databases show that binary texton could get sound results with fast feature extraction, especially when the image size is not big and the quality of image is not poor.

  9. Origin of very-short orbital-period binary systems

    International Nuclear Information System (INIS)

    Miyaji, S.

    1983-01-01

    Recent observations of four close binaries have established that there is a group of very-short orbital-period (VSOP) binaries whose orbital periods are less than 60 minutes. The VSOP binaries consist of both X-ray close binaries and cataclysmic variables. Their orbital periods are too short to have a main-sequence companion. However, four binaries, none of which belongs to any globular cluster, are too abundant to be explained by the capturing mechanism of a white dwarf. Therefore it seemed to be worthwhile to present an evolutionary scenario from an original binary system which can be applied for all VSOP binaries. (Auth.)

  10. Gas dynamics of semidetached binaries

    International Nuclear Information System (INIS)

    Lubow, S.H.; Shu, F.H.

    1975-01-01

    We analyze the gas dynamics of semidetached binary systems within the context of the Rohce model. With the adoption of the assumptions that the contact component rotates synchronously and that the flow occurs isothermally with the thermal speed being a small fraction epsilon of the relative orbital speed, Ωd, of the two stars, we show that the steady flow can be formulated in terms of a problem with multiple length scales. Using this concept, we demonstrate the following by semianalytical methods. (1) The escape of material from the surface of the contact component is accomplished by a highly nonisotropic stellar wind which reaches sonic velocities in a neighborhood of the inner Lagrangian point, L1, of size epsilon in comparison with the orbit separation d. (2) This wind throttles into a narrow stram of material which makes a prescribed angle with respect to the line joining the stellar centers ranging from 19 0 5 to 28 0 4 for the full range of possible stellar mass ratios. (3) The width of the stream scales epsilond while its density scales with epsilon -2 M-dot/Ωd 3 , where M-dot is the mass transfer rate. (4) The stream width remains nearly constant over the part of the stream which is nearly straight, and narrows somewhat as the stream curves toward the detached component. (5) If the detached component is smaller than a certain specified size, the stream results in the formation of a disk of material of prescribed size orbiting the detached component in a direct sense. A subsidi []ry issue examined briefly in this paper is the flow mechanism responsible for moving material to the equator of the contact component, and from there to the L1 region where it is lost by the directed stellar wind. Comparisons of our work are made with previous theoretical studies, and some applications are indicated

  11. Density and atomic volume in liquid Al-Fe and Al-Ni binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Plevachuk, Yu. [Ivan Franko National Univ., Lviv (Ukraine). Dept. of Metal Physics; Egry, I.; Brillo, J.; Holland-Moritz, D. [Deutsches Zentrum fuer Luft- und Raumfahrt, Koeln (Germany). Inst. fuer Raumsimulation; Kaban, I. [Chemnitz Univ. of Technolgy (Germany). Inst. of Physics

    2007-02-15

    The density of liquid Al-Fe and Al-Ni binary alloys have been determined over a wide temperature range by a noncontact technique combining electromagnetic levitation and optical dilatometry. The temperature and composition dependences of the density are analysed. A negative excess volume correlates with the negative enthalpy of mixing, compound forming ability and chemical short-range ordering in liquid Al-Fe and Al-Ni alloys. (orig.)

  12. Binaries and triples among asteroid pairs

    Science.gov (United States)

    Pravec, Petr; Scheirich, Peter; Kušnirák, Peter; Hornoch, Kamil; Galád, Adrián

    2015-08-01

    Despite major achievements obtained during the past two decades, our knowledge of the population and properties of small binary and multiple asteroid systems is still far from advanced. There is a numerous indirect evidence for that most small asteroid systems were formed by rotational fission of cohesionless parent asteroids that were spun up to the critical frequency presumably by YORP, but details of the process are lacking. Furthermore, as we proceed with observations of more and more binary and paired asteroids, we reveal new facts that substantially refine and sometimes change our understanding of the asteroid systems. One significant new finding we have recently obtained is that primaries of many asteroid pairs are actually binary or triple systems. The first such case found is (3749) Balam (Vokrouhlický, ApJL 706, L37, 2009). We have found 9 more binary systems among asteroid pairs within our ongoing NEOSource photometric project since October 2012. They are (6369) 1983 UC, (8306) Shoko, (9783) Tensho-kan, (10123) Fideoja, (21436) Chaoyichi, (43008) 1999 UD31, (44620) 1999 RS43, (46829) 1998 OS14 and (80218) 1999 VO123. We will review their characteristics. These paired binaries as we call them are mostly similar to binaries in the general ("background") population (of unpaired asteroids), but there are a few trends. The paired binaries tend to have larger secondaries with D_2/D_1 = 0.3 to 0.5 and they also tend to be wider systems with 8 of the 10 having orbital periods between 30 and 81 hours, than average among binaries in the general population. There may be also a larger fraction of triples; (3749) Balam is a confirmed triple, having a larger close and a smaller distant satellite, and (8306) Shoko and (10123) Fideoja are suspect triples as they show additional rotational lightcurve components with periods of 61 and 38.8 h that differ from the orbital period of 36.2 and 56.5 h, respectively. The unbound secondaries tend to be of the same size or

  13. Close-binary central stars of planetary nebulae

    International Nuclear Information System (INIS)

    Bond, H.E.; Grauer, A.D.

    1987-01-01

    Recent observations of PN central stars identified as binary systems are reviewed. The theoretical significance of binary central stars is discussed, and the characteristics of UU Sge, V 477 Lyr, MT Ser, LSS 2018, VW Pyx, and the central star of HFG 1 are briefly summarized. All of these binaries are shown to have periods less than 1 day, and it is estimated that about 10 percent of all binary central stars are close binaries. 27 references

  14. Magnetospheres of accreting compact objects in binary systems

    International Nuclear Information System (INIS)

    Aly, J.J.

    1985-09-01

    Bright pulsating X-ray sources (X-ray pulsars, AM Her stars,...) have been identified as strongly magnetized compact objects accreting matter from a binary companion. We give here a summary of some of the work which has been recently done to try to understand the interaction between the magnetic field of the compact object and the matter around. We examine in turn the models describing the interaction of the field with: i) a spherically symmetric accretion flow; ii) a thin keplerian accretion disk; iii) the companion itself. In all these cases, we pay particular attention to the following problems: i) how the external plasma interacting with the magnetosphere can get mixed with the field; ii) by which mechanism the magnetic field controls the mass-momentum-energy exchanges between the two stars. In conclusion, we compare the magnetosphere of an accreting compact object with that one of a planet [fr

  15. Helicity coherence in binary neutron star mergers and nonlinear feedback

    Science.gov (United States)

    Chatelain, Amélie; Volpe, Cristina

    2017-02-01

    Neutrino flavor conversion studies based on astrophysical environments usually implement neutrino mixings, neutrino interactions with matter, and neutrino self-interactions. In anisotropic media, the most general mean-field treatment includes neutrino mass contributions as well, which introduce a coupling between neutrinos and antineutrinos termed helicity or spin coherence. We discuss resonance conditions for helicity coherence for Dirac and Majorana neutrinos. We explore the role of these mean-field contributions on flavor evolution in the context of a binary neutron star merger remnant. We find that resonance conditions can be satisfied in neutron star merger scenarios while adiabaticity is not sufficient for efficient flavor conversion. We analyze our numerical findings by discussing general conditions to have multiple Mikheyev-Smirnov-Wolfenstein-like resonances, in the presence of nonlinear feedback, in astrophysical environments.

  16. Study of complex formation of 5,5'-(2 E, 2' E)-2,2'-(ethane-1,2-diylidene)bis(hydrazine-1-yl-2-ylidene)bis(4-amino-4H-1,2,4-triazole-3-thiol) (HYT) macrocyclic ligand with Cd2+ cation in non-aqueous solution by spectroscopic and conductometric methods

    Science.gov (United States)

    Mallaekeh, Hassan; Shams, Alireza; Shaker, Mohammad; Bahramzadeh, Ehsan; Arefi, Donya

    2014-12-01

    In this paper the complexation reaction of the 5,5'-(2 E,2' E)-2,2'-(ethane-1,2-diylidene)bis(hydrazine-1-yl-2-ylidene)bis(4-amino-4H-1,2,4-triazole-3-thiol) ligand (HYT) with Cd2+ education was studied in some binary mixtures of methanol (MeOH), n-propanol (PrOH) and dimethyl-formamide (DMF) at different temperatures using the conductometry and spectrophotometry. The stability constants of the complex was determined using a GENPLOT computer program. The conductance data and absorbance-mole ratio plots show that in all solvent systems, the stoichiometry of the complex formed between (HYT) and Cd2+ cation is 1: 1. The obtained results show that the stability of (HYT)-Cd complex is sensitive to the mixed solvents composition. The values of thermodynamic parameters (Δ G ∘, Δ H ∘, and Δ S ∘) for formation of (HYT)-Cd complex were obtained from temperature dependence of the stability constant using the van't Hoff plots. The results show that in most cases, the complex are enthalpy destabilized but entropy stabilized and the complex formation is affected by pH, time, temperature and the nature of the solvent.

  17. A numerical analysis of an anisotropic phase-field model for binary-fluid mixtures in the presence of magnetic-field

    OpenAIRE

    Belmiloudi , Aziz; Rasheed , Amer

    2015-01-01

    In this paper we propose a numerical scheme and perform its numerical analysis devoted to an anisotropic phase-field model with convection under the influence of magnetic field for the isother-mal solidification of binary mixtures in two-dimensional geometry. Precisely, the numerical stability and error analysis of this approximation scheme which is based on mixed finite-element method are performed. The particular application of a nickelcopper (NiCu) binary alloy, with real physical paramete...

  18. Evaluation of mixing rules for VLE calculations

    International Nuclear Information System (INIS)

    Adachi, Y.; Chung, W.K.; Lu, B.C.Y.; Yu, J.M.

    1983-01-01

    This chapter calculates vapor-liquid equilibrium (VLE) values for a number of binary systems of cryogenic interest, including hydrogen- and helium-containing mixtures, by means of several selected cubic equations of state using different sets of mixing rules. The aim is to test the capabilities of these equations for representing VLE values for the selected mixtures, and to identify and recommend the most suitable equation of state together with its compatible mixing rules for the desired data representation. It is determined that the conventional mixing rules together with the modified van der Waals equation, or the four-parameter equation, are suitable for calculating VLE values for the selected systems at cryogenic conditions. The Peng-Robinson and four-parameter equations may yield slightly better results for helium-containing systems

  19. Do stellar clusters form fewer binaries? Using moderate separation binaries to distinguish between nature and nurture

    Science.gov (United States)

    Reiter, Megan

    2017-08-01

    Fewer wide-separation binaries are found in dense stellar clusters than in looser stellar associations. It is therefore unclear whether feedback in clusters prevents the formation of multiple systems or dynamical interactions destroy them. Measuring the prevalence of close, bound binary systems provide a key test to distinguish between these possibilities. Systems with separations of 10-50 AU will survive interactions in the cluster environment, and therefore are more representative of the natal population of multiple systems. By fitting a double-star PSF, we will identify visual binaries in the Orion Nebula with separations as small as 0.03. At the distance of Orion, this corresponds to a physical separation of 12 AU, effectively closing the observational gap in the binary separation distribution left between known visual and spectroscopic binaries (>65 AU or PhD thesis.

  20. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  1. Serial binary interval ratios improve rhythm reproduction

    Directory of Open Access Journals (Sweden)

    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  2. Beyond binaries : a way forward for comparativeeducation

    Directory of Open Access Journals (Sweden)

    Marianne Larsen

    2012-09-01

    Full Text Available Binary discourses shape and produce the stories we construct about the field of comparative education. In the first part of this article, I review a set of binary discourses that have characterized social science research since the Enlightenment, including: quantitative-qualitative, nomotheticidiographic, inductive-deductive, and practice-theory. We can think of each of these binaries at opposite ends of a set of spectrums. In the second section of the paper, I show some of the ways in which these binaries have influenced the ways that we write and talk about research within the field of comparative education. I refer to the notion of binary discourses and the productive capacity of these discourses to shape our field. I then outline some critiques of these binaries to demonstrate the inherent limitations of binary discourses, and why we need to move beyond binaries in our research, and in the histories about our field. Finally, I present some tentative conclusions on ways to get ourselves out of the trap of binary thinking.Los discursos binarios moldean y producen los argumentos que construimos sobre la disciplina de la Educación Comparada. En la primera parte de este artículo, analizo un conjunto de discursos binarios que han caracterizado la investigación en Ciencias Sociales desde la Ilustración, incluyendo la cuantitativa-cualitativa, nomotética-idiográfica, inductivadeductiva, y la práctica-teoría. Podemos pensar sobre cada uno de estos discursos binarios como argumentos en los polos de un conjunto de posibilidades. En la segunda sección del artículo, revelo algunos modos en los que estos discursos binarios han influenciado las formas a través de las cuales escribimos y analizamos la investigación en el ámbito de la Educación Comparada. Analizo la noción de discursos binarios y la capacidad productiva de estos discursos de impactar nuestra ciencia. Seguidamente expongo algunas críticas de estos discursos binarios con el

  3. The binary white dwarf LHS 3236

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Hugh C.; Dahn, Conard C.; Canzian, Blaise; Guetter, Harry H.; Levine, Stephen E.; Luginbuhl, Christian B.; Monet, Alice K. B.; Stone, Ronald C.; Subasavage, John P.; Tilleman, Trudy; Walker, Richard L. [US Naval Observatory, 10391 West Naval Observatory Road, Flagstaff, AZ 86001-8521 (United States); Dupuy, Trent J.; Liu, Michael C. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Hartkopf, William I. [US Naval Observatory, 3450 Massachusetts Avenue, N.W., Washington, DC 20392-5420 (United States); Ireland, Michael J. [Department of Physics and Astronomy, Macquarie University, New South Wales, NSW 2109 (Australia); Leggett, S. K., E-mail: hch@nofs.navy.mil [Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720 (United States)

    2013-12-10

    The white dwarf LHS 3236 (WD1639+153) is shown to be a double-degenerate binary, with each component having a high mass. Astrometry at the U.S. Naval Observatory gives a parallax and distance of 30.86 ± 0.25 pc and a tangential velocity of 98 km s{sup –1}, and reveals binary orbital motion. The orbital parameters are determined from astrometry of the photocenter over more than three orbits of the 4.0 yr period. High-resolution imaging at the Keck Observatory resolves the pair with a separation of 31 and 124 mas at two epochs. Optical and near-IR photometry give a set of possible binary components. Consistency of all data indicates that the binary is a pair of DA stars with temperatures near 8000 and 7400 K and with masses of 0.93 and 0.91 M {sub ☉}; also possible is a DA primary and a helium DC secondary with temperatures near 8800 and 6000 K and with masses of 0.98 and 0.69 M {sub ☉}. In either case, the cooling ages of the stars are ∼3 Gyr and the total ages are <4 Gyr. The combined mass of the binary (1.66-1.84 M {sub ☉}) is well above the Chandrasekhar limit; however, the timescale for coalescence is long.

  4. Investigating Dark Energy with Black Hole Binaries

    International Nuclear Information System (INIS)

    Mersini-Houghton, Laura; Kelleher, Adam

    2009-01-01

    The accelerated expansion of the universe is ascribed to the existence of dark energy. Black holes accrete dark energy. The accretion induces a mass change proportional to the energy density and pressure of the background dark energy fluid. The time scale during which the mass of black holes changes considerably is long relative to the age of the universe, thus beyond detection possibilities. We propose to take advantage of the modified black hole masses for exploring the equation of state w[z] of dark energy, by investigating the evolution of supermassive black hole binaries on a dark energy background. Deriving the signatures of dark energy accretion on the evolution of binaries, we find that dark energy imprints on the emitted gravitational radiation and on the changes in the orbital radius of the binary can be within detection limits for certain supermassive black hole binaries. This talk describes how binaries can provide a useful tool in obtaining complementary information on the nature of dark energy.

  5. Star formation history: Modeling of visual binaries

    Science.gov (United States)

    Gebrehiwot, Y. M.; Tessema, S. B.; Malkov, O. Yu.; Kovaleva, D. A.; Sytov, A. Yu.; Tutukov, A. V.

    2018-05-01

    Most stars form in binary or multiple systems. Their evolution is defined by masses of components, orbital separation and eccentricity. In order to understand star formation and evolutionary processes, it is vital to find distributions of physical parameters of binaries. We have carried out Monte Carlo simulations in which we simulate different pairing scenarios: random pairing, primary-constrained pairing, split-core pairing, and total and primary pairing in order to get distributions of binaries over physical parameters at birth. Next, for comparison with observations, we account for stellar evolution and selection effects. Brightness, radius, temperature, and other parameters of components are assigned or calculated according to approximate relations for stars in different evolutionary stages (main-sequence stars, red giants, white dwarfs, relativistic objects). Evolutionary stage is defined as a function of system age and component masses. We compare our results with the observed IMF, binarity rate, and binary mass-ratio distributions for field visual binaries to find initial distributions and pairing scenarios that produce observed distributions.

  6. Determination and correlation of pyridoxine hydrochloride solubility in different binary mixtures at temperatures from (278.15 to 313.15) K

    International Nuclear Information System (INIS)

    Han, Dandan; Li, Xiaona; Wang, Haisheng; Wang, Yan; Du, Shichao; Yu, Bo; Liu, Yumin; Xu, Shijie; Gong, Junbo

    2016-01-01

    Highlights: • Solubility of pyridoxine hydrochloride in three binary mixtures was determined. • Experimental solubility of pyridoxine hydrochloride was correlated by four models. • Mixing thermodynamics of pyridoxine hydrochloride were calculated and discussed. - Abstract: The solubility of pyridoxine hydrochloride in binary solvent mixtures, including (acetone + water), (methanol + water) and (ethanol + water), was measured over temperature range from (278.15 to 313.15) K by a gravimetric method at atmospheric pressure (P = 0.1 MPa). The solubility increased with increasing temperature in binary solvent mixtures at constant solvent composition. Besides, the dissolving capacity of pyridoxine hydrochloride in the three binary solvent mixtures at constant temperature ranked as (methanol + water > ethanol + water > acetone + water) in general, partly depending on the polarity of the solvents. Additionally, the modified Apelblat equation, van’t Hoff equation, CNIBS/R–K model and Jouyban–Acree model were used to correlate the solubility data in binary mixtures, it turned out that all the selected thermodynamic models could give satisfactory results. Furthermore, the mixing thermodynamic properties of pyridoxine hydrochloride in different binary solvent mixtures were also calculated and discussed. The results indicate that the mixing process of pyridoxine hydrochloride in the selected solvents is exothermic.

  7. EVOLUTION OF THE BINARY FRACTION IN DENSE STELLAR SYSTEMS

    International Nuclear Information System (INIS)

    Fregeau, John M.; Ivanova, Natalia; Rasio, Frederic A.

    2009-01-01

    Using our recently improved Monte Carlo evolution code, we study the evolution of the binary fraction in globular clusters. In agreement with previous N-body simulations, we find generally that the hard binary fraction in the core tends to increase with time over a range of initial cluster central densities for initial binary fractions ∼<90%. The dominant processes driving the evolution of the core binary fraction are mass segregation of binaries into the cluster core and preferential destruction of binaries there. On a global scale, these effects and the preferential tidal stripping of single stars tend to roughly balance, leading to overall cluster binary fractions that are roughly constant with time. Our findings suggest that the current hard binary fraction near the half-mass radius is a good indicator of the hard primordial binary fraction. However, the relationship between the true binary fraction and the fraction of main-sequence stars in binaries (which is typically what observers measure) is nonlinear and rather complicated. We also consider the importance of soft binaries, which not only modify the evolution of the binary fraction, but can also drastically change the evolution of the cluster as a whole. Finally, we briefly describe the recent addition of single and binary stellar evolution to our cluster evolution code.

  8. Measurement and correlation of critical properties for binary mixtures and ternary mixtures containing gasoline additives

    International Nuclear Information System (INIS)

    Wang, Lipu; Han, Kewei; Xia, Shuqian; Ma, Peisheng; Yan, Fangyou

    2014-01-01

    Highlights: • A high-pressure view cell was used to measure the critical properties of mixtures. • Three binary mixtures’ and three ternary mixtures’ critical properties were reported. • The experimental data of each system covered the whole mole fraction range. • The critical properties of the ternary mixtures were predicted with the PR–WS model. • Empirical equations were used to correlate the experimental results. - Abstract: The critical properties of three binary mixtures and three ternary mixtures containing gasoline additives (including methanol + 1-propanol, heptane + ethanol, heptane + 1-propanol, methanol + 1-propanol + heptane, methanol + 1-propanol + methyl tert-butyl ether (MTBE), and ethanol + heptane + MTBE) were determined by a high-pressure cell. All the critical lines of binary mixtures belong to the type I described by Scott and van Konynenburg. The system of methanol + 1-propanol showed little non-ideal behavior due to their similar molecular structures. The heptane + ethanol and heptane + 1-propanol systems showed visible non-ideal behavior for their great differences in molecular structure. The Peng–Robinson equation of state combined with the Wong–Sandler mixing rule (PR–WS) was applied to correlate the critical properties of binary mixtures. The critical points of the three ternary mixtures were predicted by the PR–WS model with the binary interaction parameters using the procedure proposed by Heidemann and Khalil. The predicted critical temperatures were in good agreement with the experimental values, while the predicted critical pressures differed from the measured values. The experimental values of binary mixtures were fitted well with the Redlich–Kister equation. The critical properties of ternary mixtures were correlated with the Cibulka’s equation, and the critical surfaces were plotted using the Cibulka’s equations

  9. Hybrid Black-Hole Binary Initial Data

    Science.gov (United States)

    Mundim, Bruno C.; Kelly, Bernard J.; Nakano, Hiroyuki; Zlochower, Yosef; Campanelli, Manuela

    2010-01-01

    "Traditional black-hole binary puncture initial data is conformally flat. This unphysical assumption is coupled with a lack of radiation signature from the binary's past life. As a result, waveforms extracted from evolutions of this data display an abrupt jump. In Kelly et al. [Class. Quantum Grav. 27:114005 (2010)], a new binary black-hole initial data with radiation contents derived in the post-Newtonian (PN) calculations was adapted to puncture evolutions in numerical relativity. This data satisfies the constraint equations to the 2.5PN order, and contains a transverse-traceless "wavy" metric contribution, violating the standard assumption of conformal flatness. Although the evolution contained less spurious radiation, there were undesired features; the unphysical horizon mass loss and the large initial orbital eccentricity. Introducing a hybrid approach to the initial data evaluation, we significantly reduce these undesired features."

  10. Optimized reversible binary-coded decimal adders

    DEFF Research Database (Denmark)

    Thomsen, Michael Kirkedal; Glück, Robert

    2008-01-01

    Abstract Babu and Chowdhury [H.M.H. Babu, A.R. Chowdhury, Design of a compact reversible binary coded decimal adder circuit, Journal of Systems Architecture 52 (5) (2006) 272-282] recently proposed, in this journal, a reversible adder for binary-coded decimals. This paper corrects and optimizes...... their design. The optimized 1-decimal BCD full-adder, a 13 × 13 reversible logic circuit, is faster, and has lower circuit cost and less garbage bits. It can be used to build a fast reversible m-decimal BCD full-adder that has a delay of only m + 17 low-power reversible CMOS gates. For a 32-decimal (128-bit....... Keywords: Reversible logic circuit; Full-adder; Half-adder; Parallel adder; Binary-coded decimal; Application of reversible logic synthesis...

  11. A binary mixture operated heat pump

    International Nuclear Information System (INIS)

    Hihara, E.; Saito, T.

    1991-01-01

    This paper evaluates the performance of possible binary mixtures as working fluids in high- temperature heat pump applications. The binary mixtures, which are potential alternatives of fully halogenated hydrocarbons, include HCFC142b/HCFC22, HFC152a/HCFC22, HFC134a/HCFC22. The performance of the mixtures is estimated by a thermodynamic model and a practical model in which the heat transfer is considered in heat exchangers. One of the advantages of binary mixtures is a higher coefficient of performance, which is caused by the small temperature difference between the heat-sink/-source fluid and the refrigerant. The mixture HCFC142b/HCFC22 is promising from the stand point of thermodynamic performance

  12. TIDAL NOVAE IN COMPACT BINARY WHITE DWARFS

    International Nuclear Information System (INIS)

    Fuller, Jim; Lai Dong

    2012-01-01

    Compact binary white dwarfs (WDs) undergoing orbital decay due to gravitational radiation can experience significant tidal heating prior to merger. In these WDs, the dominant tidal effect involves the excitation of outgoing gravity waves in the inner stellar envelope and the dissipation of these waves in the outer envelope. As the binary orbit decays, the WDs are synchronized from outside in (with the envelope synchronized first, followed by the core). We examine the deposition of tidal heat in the envelope of a carbon-oxygen WD and study how such tidal heating affects the structure and evolution of the WD. We show that significant tidal heating can occur in the star's degenerate hydrogen layer. This layer heats up faster than it cools, triggering runaway nuclear fusion. Such 'tidal novae' may occur in all WD binaries containing a CO WD, at orbital periods between 5 minutes and 20 minutes, and precede the final merger by 10 5 -10 6 years.

  13. Compact binary hashing for music retrieval

    Science.gov (United States)

    Seo, Jin S.

    2014-03-01

    With the huge volume of music clips available for protection, browsing, and indexing, there is an increased attention to retrieve the information contents of the music archives. Music-similarity computation is an essential building block for browsing, retrieval, and indexing of digital music archives. In practice, as the number of songs available for searching and indexing is increased, so the storage cost in retrieval systems is becoming a serious problem. This paper deals with the storage problem by extending the supervector concept with the binary hashing. We utilize the similarity-preserving binary embedding in generating a hash code from the supervector of each music clip. Especially we compare the performance of the various binary hashing methods for music retrieval tasks on the widely-used genre dataset and the in-house singer dataset. Through the evaluation, we find an effective way of generating hash codes for music similarity estimation which improves the retrieval performance.

  14. Reconciliation with non-binary species trees.

    Science.gov (United States)

    Vernot, Benjamin; Stolzer, Maureen; Goldman, Aiton; Durand, Dannie

    2008-10-01

    Reconciliation extracts information from the topological incongruence between gene and species trees to infer duplications and losses in the history of a gene family. The inferred duplication-loss histories provide valuable information for a broad range of biological applications, including ortholog identification, estimating gene duplication times, and rooting and correcting gene trees. While reconciliation for binary trees is a tractable and well studied problem, there are no algorithms for reconciliation with non-binary species trees. Yet a striking proportion of species trees are non-binary. For example, 64% of branch points in the NCBI taxonomy have three or more children. When applied to non-binary species trees, current algorithms overestimate the number of duplications because they cannot distinguish between duplication and incomplete lineage sorting. We present the first algorithms for reconciling binary gene trees with non-binary species trees under a duplication-loss parsimony model. Our algorithms utilize an efficient mapping from gene to species trees to infer the minimum number of duplications in O(|V(G) | x (k(S) + h(S))) time, where |V(G)| is the number of nodes in the gene tree, h(S) is the height of the species tree and k(S) is the size of its largest polytomy. We present a dynamic programming algorithm which also minimizes the total number of losses. Although this algorithm is exponential in the size of the largest polytomy, it performs well in practice for polytomies with outdegree of 12 or less. We also present a heuristic which estimates the minimal number of losses in polynomial time. In empirical tests, this algorithm finds an optimal loss history 99% of the time. Our algorithms have been implemented in NOTUNG, a robust, production quality, tree-fitting program, which provides a graphical user interface for exploratory analysis and also supports automated, high-throughput analysis of large data sets.

  15. Microlensing Binaries Discovered through High-magnification Channel

    DEFF Research Database (Denmark)

    Shin, I.-G.; Choi, J.-Y.; Park, S.-Y.

    2012-01-01

    Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010. The perturba......Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010...

  16. Inducing Risk Neutral Preferences with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    2013-01-01

    validity of any strategic equilibrium behavior, or even the customary independence axiom. We show that subjects sampled from our population are generally risk averse when lotteries are defined over monetary outcomes, and that the binary lottery procedure does indeed induce a statistically significant shift......We evaluate the binary lottery procedure for inducing risk neutral behavior. We strip the experimental implementation down to bare bones, taking care to avoid any potentially confounding assumptions about behavior having to be made. In particular, our evaluation does not rely on the assumed...... toward risk neutrality. This striking result generalizes to the case in which subjects make several lottery choices and one is selected for payment....

  17. A simple model for binary star evolution

    International Nuclear Information System (INIS)

    Whyte, C.A.; Eggleton, P.P.

    1985-01-01

    A simple model for calculating the evolution of binary stars is presented. Detailed stellar evolution calculations of stars undergoing mass and energy transfer at various rates are reported and used to identify the dominant physical processes which determine the type of evolution. These detailed calculations are used to calibrate the simple model and a comparison of calculations using the detailed stellar evolution equations and the simple model is made. Results of the evolution of a few binary systems are reported and compared with previously published calculations using normal stellar evolution programs. (author)

  18. Non-binary or genderqueer genders

    OpenAIRE

    Richards, Christina; Bouman, Walter Pierre; Seal, Leighton; Barker, Meg John; Nieder, Timo O; T'Sjoen, Guy

    2016-01-01

    Some people have a gender which is neither male nor female and may identify as both male and female at one time, as different genders at different times, as no gender at all, or dispute the very idea of only two genders. The umbrella terms for such genders are genderqueer' or non-binary' genders. Such gender identities outside of the binary of female and male are increasingly being recognized in legal, medical and psychological systems and diagnostic classifications in line with the emerging ...

  19. Applications Of Binary Image Analysis Techniques

    Science.gov (United States)

    Tropf, H.; Enderle, E.; Kammerer, H. P.

    1983-10-01

    After discussing the conditions where binary image analysis techniques can be used, three new applications of the fast binary image analysis system S.A.M. (Sensorsystem for Automation and Measurement) are reported: (1) The human view direction is measured at TV frame rate while the subject's head is free movable. (2) Industrial parts hanging on a moving conveyor are classified prior to spray painting by robot. (3) In automotive wheel assembly, the eccentricity of the wheel is minimized by turning the tyre relative to the rim in order to balance the eccentricity of the components.

  20. Sputtering yield calculation for binary target

    International Nuclear Information System (INIS)

    Jimenez-Rodriguez, J.J.; Rodriguez-Vidal, M.; Valles-Abarca, J.A.

    1979-01-01

    The generalization for binary targets, of the ideas proposed by Sigmund for monoatomic targets, leads to a set of coupled intergrodifferential equations for the sputtering functions. After moment decomposition, the final formulae are obtained by the standard method based on the Laplace Transform, where the inverse transform is made with the aid of asymptotic expansions in the limit of very high projectile energy as compared to the surface binding energy. The possible loss of stoichiometry for binary targets is analyzed. Comparison of computed values of sputtering yield for normal incidence, with experimental results shows good agreement. (author)

  1. Binary Sparse Phase Retrieval via Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Wei Peng

    2016-01-01

    Full Text Available This paper presents the Simulated Annealing Sparse PhAse Recovery (SASPAR algorithm for reconstructing sparse binary signals from their phaseless magnitudes of the Fourier transform. The greedy strategy version is also proposed for a comparison, which is a parameter-free algorithm. Sufficient numeric simulations indicate that our method is quite effective and suggest the binary model is robust. The SASPAR algorithm seems competitive to the existing methods for its efficiency and high recovery rate even with fewer Fourier measurements.

  2. Testing the Binary Black Hole Nature of a Compact Binary Coalescence.

    Science.gov (United States)

    Krishnendu, N V; Arun, K G; Mishra, Chandra Kant

    2017-09-01

    We propose a novel method to test the binary black hole nature of compact binaries detectable by gravitational wave (GW) interferometers and, hence, constrain the parameter space of other exotic compact objects. The spirit of the test lies in the "no-hair" conjecture for black holes where all properties of a Kerr black hole are characterized by its mass and spin. The method relies on observationally measuring the quadrupole moments of the compact binary constituents induced due to their spins. If the compact object is a Kerr black hole (BH), its quadrupole moment is expressible solely in terms of its mass and spin. Otherwise, the quadrupole moment can depend on additional parameters (such as the equation of state of the object). The higher order spin effects in phase and amplitude of a gravitational waveform, which explicitly contains the spin-induced quadrupole moments of compact objects, hence, uniquely encode the nature of the compact binary. Thus, we argue that an independent measurement of the spin-induced quadrupole moment of the compact binaries from GW observations can provide a unique way to distinguish binary BH systems from binaries consisting of exotic compact objects.

  3. The fate of close encounters between binary stars and binary supermassive black holes

    Science.gov (United States)

    Wang, Yi-Han; Leigh, Nathan; Yuan, Ye-Fei; Perna, Rosalba

    2018-04-01

    The evolution of main-sequence binaries that reside in the Galactic Centre can be heavily influenced by the central supermassive black hole (SMBH). Due to these perturbative effects, the stellar binaries in dense environments are likely to experience mergers, collisions, or ejections through secular and/or non-secular interactions. More direct interactions with the central SMBH are thought to produce hypervelocity stars (HVSs) and tidal disruption events (TDEs). In this paper, we use N-body simulations to study the dynamics of stellar binaries orbiting a central SMBH primary with an outer SMBH secondary orbiting this inner triple. The effects of the secondary SMBH on the event rates of HVSs, TDEs, and stellar mergers are investigated, as a function of the SMBH-SMBH binary mass ratio. Our numerical experiments reveal that, relative to the isolated SMBH case, the TDE and HVS rates are enhanced for, respectively, the smallest and largest mass ratio SMBH-SMBH binaries. This suggests that the observed event rates of TDEs and HVSs have the potential to serve as a diagnostic of the mass ratio of a central SMBH-SMBH binary. The presence of a secondary SMBH also allows for the creation of hypervelocity binaries. Observations of these systems could thus constrain the presence of a secondary SMBH in the Galactic Centre.

  4. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. I. S-TYPE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Kaltenegger, Lisa [MPIA, Koenigstuhl 17, D-69117 Heidelberg (Germany); Haghighipour, Nader, E-mail: kaltenegger@mpia.de [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii-Manoa, Honolulu, HI 96822 (United States)

    2013-11-10

    We have developed a comprehensive methodology for calculating the boundaries of the habitable zone (HZ) of planet-hosting S-type binary star systems. Our approach is general and takes into account the contribution of both stars to the location and extent of the binary HZ with different stellar spectral types. We have studied how the binary eccentricity and stellar energy distribution affect the extent of the HZ. Results indicate that in binaries where the combination of mass-ratio and orbital eccentricity allows planet formation around a star of the system to proceed successfully, the effect of a less luminous secondary on the location of the primary's HZ is generally negligible. However, when the secondary is more luminous, it can influence the extent of the HZ. We present the details of the derivations of our methodology and discuss its application to the binary HZ around the primary and secondary main-sequence stars of an FF, MM, and FM binary, as well as two known planet-hosting binaries α Cen AB and HD 196886.

  5. CALCULATING THE HABITABLE ZONE OF BINARY STAR SYSTEMS. I. S-TYPE BINARIES

    International Nuclear Information System (INIS)

    Kaltenegger, Lisa; Haghighipour, Nader

    2013-01-01

    We have developed a comprehensive methodology for calculating the boundaries of the habitable zone (HZ) of planet-hosting S-type binary star systems. Our approach is general and takes into account the contribution of both stars to the location and extent of the binary HZ with different stellar spectral types. We have studied how the binary eccentricity and stellar energy distribution affect the extent of the HZ. Results indicate that in binaries where the combination of mass-ratio and orbital eccentricity allows planet formation around a star of the system to proceed successfully, the effect of a less luminous secondary on the location of the primary's HZ is generally negligible. However, when the secondary is more luminous, it can influence the extent of the HZ. We present the details of the derivations of our methodology and discuss its application to the binary HZ around the primary and secondary main-sequence stars of an FF, MM, and FM binary, as well as two known planet-hosting binaries α Cen AB and HD 196886

  6. BROWN DWARF BINARIES FROM DISINTEGRATING TRIPLE SYSTEMS

    International Nuclear Information System (INIS)

    Reipurth, Bo; Mikkola, Seppo

    2015-01-01

    Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to

  7. BROWN DWARF BINARIES FROM DISINTEGRATING TRIPLE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Reipurth, Bo [Institute for Astronomy and NASA Astrobiology Institute University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Mikkola, Seppo, E-mail: reipurth@ifa.hawaii.edu, E-mail: Seppo.Mikkola@utu.fi [Tuorla Observatory, University of Turku, Väisäläntie 20, Piikkiö (Finland)

    2015-04-15

    Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to

  8. Estimation of the viscosities of liquid binary alloys

    Science.gov (United States)

    Wu, Min; Su, Xiang-Yu

    2018-01-01

    As one of the most important physical and chemical properties, viscosity plays a critical role in physics and materials as a key parameter to quantitatively understanding the fluid transport process and reaction kinetics in metallurgical process design. Experimental and theoretical studies on liquid metals are problematic. Today, there are many empirical and semi-empirical models available with which to evaluate the viscosity of liquid metals and alloys. However, the parameter of mixed energy in these models is not easily determined, and most predictive models have been poorly applied. In the present study, a new thermodynamic parameter Δ G is proposed to predict liquid alloy viscosity. The prediction equation depends on basic physical and thermodynamic parameters, namely density, melting temperature, absolute atomic mass, electro-negativity, electron density, molar volume, Pauling radius, and mixing enthalpy. Our results show that the liquid alloy viscosity predicted using the proposed model is closely in line with the experimental values. In addition, if the component radius difference is greater than 0.03 nm at a certain temperature, the atomic size factor has a significant effect on the interaction of the binary liquid metal atoms. The proposed thermodynamic parameter Δ G also facilitates the study of other physical properties of liquid metals.

  9. A Variational approach to thin film hydrodynamics of binary mixtures

    KAUST Repository

    Xu, Xinpeng

    2015-02-04

    In order to model the dynamics of thin films of mixtures, solutions, and suspensions, a thermodynamically consistent formulation is needed such that various coexisting dissipative processes with cross couplings can be correctly described in the presence of capillarity, wettability, and mixing effects. In the present work, we apply Onsager\\'s variational principle to the formulation of thin film hydrodynamics for binary fluid mixtures. We first derive the dynamic equations in two spatial dimensions, one along the substrate and the other normal to the substrate. Then, using long-wave asymptotics, we derive the thin film equations in one spatial dimension along the substrate. This enables us to establish the connection between the present variational approach and the gradient dynamics formulation for thin films. It is shown that for the mobility matrix in the gradient dynamics description, Onsager\\'s reciprocal symmetry is automatically preserved by the variational derivation. Furthermore, using local hydrodynamic variables, our variational approach is capable of introducing diffusive dissipation beyond the limit of dilute solute. Supplemented with a Flory-Huggins-type mixing free energy, our variational approach leads to a thin film model that treats solvent and solute in a symmetric manner. Our approach can be further generalized to include more complicated free energy and additional dissipative processes.

  10. Comparative study of binary and ternary complexes of some rare earths

    International Nuclear Information System (INIS)

    Makhijani, S.D.; Sangal, S.P.

    1978-01-01

    Modified form of Irving and Rossotti's pH titration technique has been used to evaluate and compare the stability constants of the binary and ternary complexes of Sc(III), Y(III), La(III), Pr(III), Nd(III) and Sm(III) at 30 0 at an ionic strength of 0.2M NaClO 4 . For the study of ternary complexes, nitrilotriacetic acid has been used as a primary ligand and polyhydroxy phenols i.e. pyrocatechol (PYC), pyrogallol (PYG) and gallic acid (GA) as secondary ligands. The stability constants of the binary complexes were found to be more than those of the corresponding ternary complexes which can reasonably be explained on the basis of electrostatic force between primary complex (metal in the case of binary complex) and secondary ligand, and space available to accommodate the secondary ligand. The stability decreases with the increase in ionic radii, i.e. Sc(III)>Y(III)>Sm(III)>Nd(III)>Pr(III)>La(III). In terms of secondary ligand, it follows the order PYC>GA>PYG. Rare earths form only 1:1 binary complex, and 1:1:1 mixed ligand complex in all the cases. (author)

  11. Experimental study on thermal storage performance of binary mixtures of fatty acids

    Science.gov (United States)

    Yan, Quanying; Zhang, Jing; Liu, Chao; Liu, Sha; Sun, Xiangyu

    2018-02-01

    We selected five kinds of fatty acids including the capric acid, stearic acid, lauric acid, palmitic acid and myristic acid and mixed them to prepare10 kinds of binary mixtures of fatty acids according to the predetermined proportion,tested the phase change temperature and latent heat of mixtures by differential scanning calorimetry(DSC). In order to find the fatty acid mixture which has suitable phase change temperature, the larger phase change latent heat and can be used for phase change wall. The results showed that the phase change temperature and latent heats of the binary mixtures of fatty acids decreased compared with the single component;The phase change temperature of the binary mixtures of fatty acids containing capric acid were lower, the range was roughly 20∼30°C,and latent heat is large,which are ideal phase change materials for phase change wall energy storage;The phase change temperature of the binary mixtures consisting of other fatty acids were still high,didn’t meet the temperature requirements of the wall energy storage.

  12. Experimental vapor-liquid equilibria data for binary mixtures of xylene isomers

    Directory of Open Access Journals (Sweden)

    W.L. Rodrigues

    2005-09-01

    Full Text Available Separation of aromatic C8 compounds by distillation is a difficult task due to the low relative volatilities of the compounds and to the high degree of purity required of the final commercial products. For rigorous simulation and optimization of this separation, the use of a model capable of describing vapor-liquid equilibria accurately is necessary. Nevertheless, experimental data are not available for all binaries at atmospheric pressure. Vapor-liquid equilibria data for binary mixtures were isobarically obtained with a modified Fischer cell at 100.65 kPa. The vapor and liquid phase compositions were analyzed with a gas chromatograph. The methodology was initially tested for cyclo-hexane+n-heptane data; results obtained are similar to other data in the literature. Data for xylene binary mixtures were then obtained, and after testing, were considered to be thermodynamically consistent. Experimental data were regressed with Aspen Plus® 10.1 and binary interaction parameters were reported for the most frequently used activity coefficient models and for the classic mixing rules of two cubic equations of state.

  13. A new design method for fluidized bed conversion of largely heterogeneous binary fuels

    Directory of Open Access Journals (Sweden)

    Szentannai Pal

    2017-01-01

    Full Text Available Binary fuels of a fluidized bed combustor or gasifier are solids composed of two groups of particles. Their optimal handling in the same bed becomes rather difficult if their hydrodynamic properties differ by two orders of magnitude or more. Both of these fuel classes are directly fed into the reactor in most cases but the rather homogeneous fuel originally fed switches into a binary character inside the reactor in some others. A typical example of the latter case is the thermal utilization of rubber wastes. A novel design is proposed in the present paper by setting up a non-mixing, non-elutriated binary bed. Design criteria and procedure are formulated as well. One of the known calculation methods is proposed to be applied for assuring a segregated bed by means of choosing the bed components, geometry, and gas velocity conveniently. Cold model experiments are proposed to be applied for assuring no elutriation of the fine fuel particles and no sinking of the coarse fuel particles in the same time. A simple experiment is proposed for determining the common minimum fluidization velocity of the binary bed because known calculation methods can not be applied here.

  14. Electrostatic and capillary force directed tunable 3D binary micro- and nanoparticle assemblies on surfaces

    International Nuclear Information System (INIS)

    Singh, G; Pillai, S; Arpanaei, A; Kingshott, P

    2011-01-01

    We report a simple, rapid and cost-effective method based on evaporation induced assembly to grow 3D binary colloidal assemblies on a hydrophobic/hydrophilic substrate by simple drop casting. The evaporation of a mixed colloidal drop results in ring-like or uniform area deposition depending on the concentration of particles, and thus assembly occurs at the periphery of a ring or uniformly all over the drop area. Binary colloidal assemblies of different crystal structure are successfully prepared over a wide range of size ratios (γ = small/large) from 0.06 to 0.30 by tuning the γ of the micro- and nanoparticles used during assembly. The growth mechanism of 3D binary colloidal assemblies is investigated and it is found that electrostatic forces facilitate assembly formation until the end of the evaporation process, with capillary forces also playing a role. In addition, the effects of solvent type, humidity, and salt concentration on crystal formation and ordering behaviour are also examined. Furthermore, long range, highly ordered binary colloidal assemblies can be fabricated by the choice of a low conducting solvent combined with evaporation induced assembly.

  15. Phase behaviour, interactions, and structural studies of (amines+ionic liquids) binary mixtures.

    Science.gov (United States)

    Jacquemin, Johan; Bendová, Magdalena; Sedláková, Zuzana; Blesic, Marijana; Holbrey, John D; Mullan, Claire L; Youngs, Tristan G A; Pison, Laure; Wagner, Zdeněk; Aim, Karel; Costa Gomes, Margarida F; Hardacre, Christopher

    2012-05-14

    We present a study on the phase equilibrium behaviour of binary mixtures containing two 1-alkyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide-based ionic liquids, [C(n)mim] [NTf(2)] (n=2 and 4), mixed with diethylamine or triethylamine as a function of temperature and composition using different experimental techniques. Based on this work, two systems showing an LCST and one system with a possible hourglass shape are measured. Their phase behaviours are then correlated and predicted by using Flory-Huggins equations and the UNIQUAC method implemented in Aspen. The potential of the COSMO-RS methodology to predict the phase equilibria was also tested for the binary systems studied. However, this methodology is unable to predict the trends obtained experimentally, limiting its use for systems involving amines in ionic liquids. The liquid-state structure of the binary mixture ([C(2)mim] [NTf(2)]+diethylamine) is also investigated by molecular dynamics simulation and neutron diffraction. Finally, the absorption of gaseous ethane by the ([C(2)mim][NTf(2)]+diethylamine) binary mixture is determined and compared with that observed in the pure solvents. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. A mixed model framework for teratology studies.

    Science.gov (United States)

    Braeken, Johan; Tuerlinckx, Francis

    2009-10-01

    A mixed model framework is presented to model the characteristic multivariate binary anomaly data as provided in some teratology studies. The key features of the model are the incorporation of covariate effects, a flexible random effects distribution by means of a finite mixture, and the application of copula functions to better account for the relation structure of the anomalies. The framework is motivated by data of the Boston Anticonvulsant Teratogenesis study and offers an integrated approach to investigate substantive questions, concerning general and anomaly-specific exposure effects of covariates, interrelations between anomalies, and objective diagnostic measurement.

  17. Ultracompact X-ray binary stars

    NARCIS (Netherlands)

    Haaften, L.M. van

    2013-01-01

    Ultracompact X-ray binary stars usually consist of a neutron star and a white dwarf, two stars bound together by their strong gravity and orbiting each other very rapidly, completing one orbit in less than one hour. Neutron stars are extremely compact remnants of the collapsed cores of massive stars

  18. Jet precession in binary black holes

    Science.gov (United States)

    Abraham, Zulema

    2018-06-01

    Supermassive binary black holes are thought to lie at the centres of merging galaxies. The blazar OJ 287 is the poster child of such systems, showing strong and periodic variability across the electromagnetic spectrum. A new study questions the physical origin of this variability.

  19. Mesoscopic electrohydrodynamic simulations of binary colloidal suspensions

    NARCIS (Netherlands)

    Rivas, Nicolas; Frijters, Stefan; Pagonabarraga, Ignacio; Harting, Jens

    2018-01-01

    A model is presented for the solution of electrokinetic phenomena of colloidal suspensions in fluid mixtures. We solve the discrete Boltzmann equation with a Bhatnagar-Gross-Krook collision operator using the lattice Boltzmann method to simulate binary fluid flows. Solvent-solvent and solvent-solute

  20. Smoothed analysis of binary search trees

    NARCIS (Netherlands)

    Manthey, Bodo; Reischuk, Rüdiger

    2007-01-01

    Binary search trees are one of the most fundamental data structures. While the height of such a tree may be linear in the worst case, the average height with respect to the uniform distribution is only logarithmic. The exact value is one of the best studied problems in average-case complexity. We

  1. A coinductive calculus of binary trees

    NARCIS (Netherlands)

    A.M. Silva (Alexandra); J.J.M.M. Rutten (Jan)

    2007-01-01

    htmlabstractWe study the set T_A of infinite binary trees with nodes labelled in a semiring A from a coalgebraic perspective. We present coinductive definition and proof principles based on the fact that T_A carries a final coalgebra structure. By viewing trees as formal power series, we develop a

  2. Binary palmprint representation for feature template protection

    NARCIS (Netherlands)

    Mu, Meiru; Ruan, Qiuqi; Shao, X.; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

    2012-01-01

    The major challenge of biometric template protection comes from the intraclass variations of biometric data. The helper data scheme aims to solve this problem by employing the Error Correction Codes (ECC). However, many reported biometric binary features from the same user reach bit error rate (BER)

  3. The average size of ordered binary subgraphs

    NARCIS (Netherlands)

    van Leeuwen, J.; Hartel, Pieter H.

    To analyse the demands made on the garbage collector in a graph reduction system, the change in size of an average graph is studied when an arbitrary edge is removed. In ordered binary trees the average number of deleted nodes as a result of cutting a single edge is equal to the average size of a

  4. Short-timescale variability in cataclysmic binaries

    International Nuclear Information System (INIS)

    Cordova, F.A.; Mason, K.O.

    1982-01-01

    Rapid variability, including flickering and pulsations, has been detected in cataclysmic binaries at optical and x-ray frequencies. In the case of the novalike variable TT Arietis, simultaneous observations reveal that the x-ray and optical flickering activity is strongly correlated, while short period pulsations are observed that occur at the same frequencies in both wavelength bands

  5. Non-binary or genderqueer genders.

    Science.gov (United States)

    Richards, Christina; Bouman, Walter Pierre; Seal, Leighton; Barker, Meg John; Nieder, Timo O; T'Sjoen, Guy

    2016-01-01

    Some people have a gender which is neither male nor female and may identify as both male and female at one time, as different genders at different times, as no gender at all, or dispute the very idea of only two genders. The umbrella terms for such genders are 'genderqueer' or 'non-binary' genders. Such gender identities outside of the binary of female and male are increasingly being recognized in legal, medical and psychological systems and diagnostic classifications in line with the emerging presence and advocacy of these groups of people. Population-based studies show a small percentage--but a sizable proportion in terms of raw numbers--of people who identify as non-binary. While such genders have been extant historically and globally, they remain marginalized, and as such--while not being disorders or pathological in themselves--people with such genders remain at risk of victimization and of minority or marginalization stress as a result of discrimination. This paper therefore reviews the limited literature on this field and considers ways in which (mental) health professionals may assist the people with genderqueer and non-binary gender identities and/or expressions they may see in their practice. Treatment options and associated risks are discussed.

  6. Some thoughts on interacting binary systems

    International Nuclear Information System (INIS)

    Ulrich, R.K.

    1980-01-01

    The author presents some thoughts on the theory and observation of interacting binary systems. The complex physical processes possible in these systems make our present understanding inconclusive. New types of observation (X-ray, EUV, radio) present new challenges to the theoretician. The author discusses those problems which seem to hold the most promise for future progress. (Auth.)

  7. Mass loss from interacting close binary systems

    Science.gov (United States)

    Plavec, M. J.

    1981-01-01

    The three well-defined classes of evolved binary systems that show evidence of present and/or past mass loss are the cataclysmic variables, the Algols, and Wolf-Rayet stars. It is thought that the transformation of supergiant binary systems into the very short-period cataclysmic variables must have been a complex process. The new evidence that has recently been obtained from the far ultraviolet spectra that a certain subclass of the Algols (the Serpentids) are undergoing fairly rapid evolution is discussed. It is thought probable that the remarkable mass outflow observed in them is connected with a strong wind powered by accretion. The origin of the circumbinary clouds or flat disks that probably surround many strongly interacting binaries is not clear. Attention is also given to binary systems with hot white dwarf or subdwarf components, such as the symbiotic objects and the BQ stars; it is noted that in them both components may be prone to an enhanced stellar wind.

  8. Stretchable Binary Fresnel Lens for Focus Tuning

    NARCIS (Netherlands)

    Li, X.; Wei, L.; Poelma, R.H.; Vollebregt, S.; Wei, J.; Urbach, Paul; Sarro, P.M.; Zhang, G.Q.

    2016-01-01

    This paper presents a tuneable binary amplitude Fresnel lens produced by wafer-level microfabrication. The Fresnel lens is fabricated by encapsulating lithographically defined vertically aligned carbon nanotube (CNT) bundles inside a polydimethyl-siloxane (PDMS) layer. The composite lens material

  9. Flip-flopping binary black holes.

    Science.gov (United States)

    Lousto, Carlos O; Healy, James

    2015-04-10

    We study binary spinning black holes to display the long term individual spin dynamics. We perform a full numerical simulation starting at an initial proper separation of d≈25M between equal mass holes and evolve them down to merger for nearly 48 orbits, 3 precession cycles, and half of a flip-flop cycle. The simulation lasts for t=20 000M and displays a total change in the orientation of the spin of one of the black holes from an initial alignment with the orbital angular momentum to a complete antialignment after half of a flip-flop cycle. We compare this evolution with an integration of the 3.5 post-Newtonian equations of motion and spin evolution to show that this process continuously flip flops the spin during the lifetime of the binary until merger. We also provide lower order analytic expressions for the maximum flip-flop angle and frequency. We discuss the effects this dynamics may have on spin growth in accreting binaries and on the observational consequences for galactic and supermassive binary black holes.

  10. Compiler-Agnostic Function Detection in Binaries

    NARCIS (Netherlands)

    Andriesse, D.A.; Slowinska, J.M.; Bos, H.J.

    2017-01-01

    We propose Nucleus, a novel function detection algorithm for binaries. In contrast to prior work, Nucleus is compiler-agnostic, and does not require any learning phase or signature information. Instead of scanning for signatures, Nucleus detects functions at the Control Flow Graph-level, making it

  11. Photometric survey of asynchronous binary asteroids

    Czech Academy of Sciences Publication Activity Database

    Pravec, Petr; Scheirich, Peter; Kušnirák, Peter; Kotková, Lenka; Mottola, S.; Hahn, G.; Brown, P.; Esquerdo, G.; Kaiser, K.; Krzeminski, Z.; Pray, D. P.; Warner, B. D.; Harris, A. W.; Nolan, M. C.; Howell, E. S.; Benner, L. A. M.; Margot, J. L.; Galád, Adrián; Holliday, W.; Hicks, M. D.; Krugly, Yu. N.; Tholen, D.; Whiteley, R.; Marchis, F.; DeGraff, D. R.; Grauer, A.; Larson, S. M.; Velichko, F. P.; Cooney, W.R.; Stephens, R.; Zhu, J.; Kirsch, K.; Dyvig, R.; Snyder, L.; Reddy, V.; Moore, S.; Gajdoš, Š.; Világi, J.; Masi, G.; Higgins, D.; Funkhouser, G. M.; Knight, B.; Slivan, S. M.; Behrend, R.; Grenon, M.; Burki, G.; Roy, R.; Demeautis, C.; Matter, D.; Waelchli, N.; Revaz, Y.; Klotz, A.; Rieugné, M.; Thieri, P.; Cotrez, V.; Brunetto, L.; Kober, G.

    2006-01-01

    Roč. 181, č. 1 (2006), s. 63-93 ISSN 0019-1035 R&D Projects: GA ČR GA205/05/0604; GA AV ČR IAA3003204 Institutional research plan: CEZ:AV0Z10030501 Keywords : asteroids * binary * photometry Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.151, year: 2006

  12. Planar quark diagrams and binary spin processes

    International Nuclear Information System (INIS)

    Grigoryan, A.A.; Ivanov, N.Ya.

    1986-01-01

    Contributions of planar diagrams to the binary scattering processes are analyzed. The analysis is based on the predictions of quark-gluon picture of strong interactions for the coupling of reggeons with quarks as well as on the SU(6)-classification of hadrons. The dependence of contributions of nonplanar corrections on spins and quark composition of interacting particles is discussed

  13. Binary translation using peephole translation rules

    Science.gov (United States)

    Bansal, Sorav; Aiken, Alex

    2010-05-04

    An efficient binary translator uses peephole translation rules to directly translate executable code from one instruction set to another. In a preferred embodiment, the translation rules are generated using superoptimization techniques that enable the translator to automatically learn translation rules for translating code from the source to target instruction set architecture.

  14. Predicting Social Trust with Binary Logistic Regression

    Science.gov (United States)

    Adwere-Boamah, Joseph; Hufstedler, Shirley

    2015-01-01

    This study used binary logistic regression to predict social trust with five demographic variables from a national sample of adult individuals who participated in The General Social Survey (GSS) in 2012. The five predictor variables were respondents' highest degree earned, race, sex, general happiness and the importance of personally assisting…

  15. Face Alignment via Regressing Local Binary Features.

    Science.gov (United States)

    Ren, Shaoqing; Cao, Xudong; Wei, Yichen; Sun, Jian

    2016-03-01

    This paper presents a highly efficient and accurate regression approach for face alignment. Our approach has two novel components: 1) a set of local binary features and 2) a locality principle for learning those features. The locality principle guides us to learn a set of highly discriminative local binary features for each facial landmark independently. The obtained local binary features are used to jointly learn a linear regression for the final output. This approach achieves the state-of-the-art results when tested on the most challenging benchmarks to date. Furthermore, because extracting and regressing local binary features are computationally very cheap, our system is much faster than previous methods. It achieves over 3000 frames per second (FPS) on a desktop or 300 FPS on a mobile phone for locating a few dozens of landmarks. We also study a key issue that is important but has received little attention in the previous research, which is the face detector used to initialize alignment. We investigate several face detectors and perform quantitative evaluation on how they affect alignment accuracy. We find that an alignment friendly detector can further greatly boost the accuracy of our alignment method, reducing the error up to 16% relatively. To facilitate practical usage of face detection/alignment methods, we also propose a convenient metric to measure how good a detector is for alignment initialization.

  16. Structure Map for Embedded Binary Alloy Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, C.W.; Shin, S.J.; Liao, C.Y.; Guzman, J.; Stone, P.R.; Watanabe, M.; Ager III, J.W.; Haller, E.E.; Chrzan, D.C.

    2008-09-20

    The equilibrium structure of embedded nanocrystals formed from strongly segregating binary-alloys is considered within a simple thermodynamic model. The model identifies two dimensionlessinterface energies that dictate the structure, and allows prediction of the stable structure for anychoice of these parameters. The resulting structure map includes three distinct nanocrystal mor-phologies: core/shell, lobe/lobe, and completely separated spheres.

  17. ANGULAR-MOMENTUM IN BINARY SPIRAL GALAXIES

    NARCIS (Netherlands)

    OOSTERLOO, T

    In order to investigate the relative orientations of spiral galaxies in pairs, the distribution of the angle between the spin-vectors for a new sample of 40 binary spiral galaxies is determined. From this distribution it is found, contrary to an earlier result obtained by Helou (1984), that there is

  18. Gravitational waves from binary black holes

    Indian Academy of Sciences (India)

    Raman Research Institute, C.V. Raman Avenue, Sadashivanagar, Bangalore ... In the 1916 paper exploring the physical implications of GR, Einstein .... Thus, for a neutron star binary in the Virgo cluster (D = 18 Mpc; 5.6×1020 km) the strain.

  19. The Binary Pulsar: Gravity Waves Exist.

    Science.gov (United States)

    Will, Clifford

    1987-01-01

    Reviews the history of pulsars generally and the 1974 discovery of the binary pulsar by Joe Taylor and Russell Hulse specifically. Details the data collection and analysis used by Taylor and Hulse. Uses this discussion as support for Albert Einstein's theory of gravitational waves. (CW)

  20. Receptive fields selection for binary feature description.

    Science.gov (United States)

    Fan, Bin; Kong, Qingqun; Trzcinski, Tomasz; Wang, Zhiheng; Pan, Chunhong; Fua, Pascal

    2014-06-01

    Feature description for local image patch is widely used in computer vision. While the conventional way to design local descriptor is based on expert experience and knowledge, learning-based methods for designing local descriptor become more and more popular because of their good performance and data-driven property. This paper proposes a novel data-driven method for designing binary feature descriptor, which we call receptive fields descriptor (RFD). Technically, RFD is constructed by thresholding responses of a set of receptive fields, which are selected from a large number of candidates according to their distinctiveness and correlations in a greedy way. Using two different kinds of receptive fields (namely rectangular pooling area and Gaussian pooling area) for selection, we obtain two binary descriptors RFDR and RFDG .accordingly. Image matching experiments on the well-known patch data set and Oxford data set demonstrate that RFD significantly outperforms the state-of-the-art binary descriptors, and is comparable with the best float-valued descriptors at a fraction of processing time. Finally, experiments on object recognition tasks confirm that both RFDR and RFDG successfully bridge the performance gap between binary descriptors and their floating-point competitors.

  1. Binary nucleation of water and sodium chloride

    Czech Academy of Sciences Publication Activity Database

    Němec, Tomáš; Maršík, František; Palmer, A.

    2006-01-01

    Roč. 124, č. 4 (2006), 0445091-0445096 ISSN 0021-9606 R&D Projects: GA ČR(CZ) GA101/05/2536 Institutional research plan: CEZ:AV0Z20760514 Keywords : binary nucleation * sodium chloride * water Subject RIV: BJ - Thermodynamics Impact factor: 3.166, year: 2006

  2. The Benchmark Eclipsing Binary V530 Ori

    DEFF Research Database (Denmark)

    Torres, Guillermo; Lacy, Claud H. Sandberg; Pavlovski, Kresimir

    2015-01-01

    We report accurate measurements of the physical properties (mass, radius, temperature) of components of the G+M eclipsing binary V530 On. The M-type secondary shows a larger radius and a cooler temperature than predicted by standard stellar evolution models, as has been found for many other low...

  3. Void formation in irradiated binary nickel alloys

    International Nuclear Information System (INIS)

    Shaikh, M.A.; Ahmed, M.; Akhter, J.I.

    1994-01-01

    In this work a computer program has been used to compute void radius, void density and swelling parameter for nickel and binary nickel-carbon alloys irradiated with nickel ions of 100 keV. The aim is to compare the computed results with experimental results already reported

  4. The mixing effects for real gases and their mixtures

    Science.gov (United States)

    Gong, M. Q.; Luo, E. C.; Wu, J. F.

    2004-10-01

    The definitions of the adiabatic and isothermal mixing effects in the mixing processes of real gases were presented in this paper. Eight substances with boiling-point temperatures from cryogenic temperature to the ambient temperature were selected from the interest of low temperature refrigeration to study their binary and multicomponent mixing effects. Detailed analyses were made on the parameters of the mixing process to know their influences on mixing effects. Those parameters include the temperatures, pressures, and mole fraction ratios of pure substances before mixing. The results show that the maximum temperature variation occurs at the saturation state of each component in the mixing process. Those components with higher boiling-point temperatures have higher isothermal mixing effects. The maximum temperature variation which is defined as the adiabatic mixing effect can even reach up to 50 K, and the isothermal mixing effect can reach about 20 kJ/mol. The possible applications of the mixing cooling effect in both open cycle and closed cycle refrigeration systems were also discussed.

  5. Estimation of the minimum Prandtl number for binary gas mixtures formed with light helium and certain heavier gases: Application to thermoacoustic refrigerators

    International Nuclear Information System (INIS)

    Campo, Antonio; Papari, Mohammad M.; Abu-Nada, Eiyad

    2011-01-01

    This paper addresses a detailed procedure for the accurate estimation of low Prandtl numbers of selected binary gas mixtures. In this context, helium (He) is the light primary gas and the heavier secondary gases are nitrogen (N 2 ), oxygen (O 2 ), xenon (Xe), carbon dioxide (CO 2 ), methane (CH 4 ), tetrafluoromethane or carbon tetrafluoride (CF 4 ) and sulfur hexafluoride (SF 6 ). The three thermophysical properties forming the Prandtl number of binary gas mixtures Pr mix are heat capacity at constant pressure C p,mix (thermodynamic property), viscosity η mix (transport property) and thermal conductivity λ mix (transport property), which in general depend on temperature T and molar gas composition w. The precise formulas for the calculation of the trio C p,mix , η mix , and λ mix are gathered from various dependable sources. When the set of computed Pr mix values for the seven binary gas mixtures He + N 2 , He + O 2 , He + Xe, He + CO 2 , He + CH 4 , He + CF 4 , He + SF 6 at atmospheric conditions T = 300 K, p = 1 atm is plotted against the molar gas composition w on the w-domain [0,1], the family of Pr mix (w) curves exhibited distinctive concave shapes. In the curves format, all Pr mix (w) curves initiate with Pr ∼ 0.7 at w = 0 (associated with light primary He). Forthwith, each Pr mix (w) curve descends to a unique minimum and thereafter ascend back to Pr ∼ 0.7 at the terminal point w = 1 (connected to heavier secondary gases). Overall, it was found that among the seven binary gas mixtures tested, the He + Xe gas mixture delivered the absolute minimum Prandtl number Pr mix,min = 0.12 at the optimal molar gas composition w opt = 0.975. - Highlights: →Accurate estimation of low Prandtl numbers for some helium-based binary gas mixtures. →The thermophysical properties of the gases are calculated with precise formulas. →The absolute minimum Prandtl number is delivered by the He + Xe binary gas mixture. →Application to experimental thermoacoustic

  6. Mixed Connective Tissue Disease

    Science.gov (United States)

    Mixed connective tissue disease Overview Mixed connective tissue disease has signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis. For this reason, mixed connective tissue disease ...

  7. Fluid mixing III

    International Nuclear Information System (INIS)

    Harnby, N.

    1988-01-01

    Covering all aspects of mixing, this work presents research and developments in industrial applications, flow patterns and mixture analysis, mixing of solids into liquids, and mixing of gases into liquids

  8. Evolution of binaries with compact objects in globular clusters

    OpenAIRE

    Ivanova, Natalia

    2017-01-01

    Dynamical interactions that take place between objects in dense stellar systems lead to frequent formation of exotic stellar objects, unusual binaries, and systems of higher multiplicity. They are most important for the formation of binaries with neutron stars and black holes, which are usually observationally revealed in mass-transferring binaries. Here we review the current understanding of compact object's retention, of the metallicity dependence on the formation of low-mass X-ray binaries...

  9. Influence of non-binary effects on intranuclear cascade method

    International Nuclear Information System (INIS)

    Gomes, E.H.C.

    1985-01-01

    The importance of non binary process effects in the intranuclear cascade method is analysed. It is shown that, in the higher density steps, the non binary collisions lead to baryon density distribution and rapidity differents from the one obtained using the usual intranuclear cascade method (limited to purely binary collisions). The validity of the applications of binary intranuclear cascade method to the simulation of the thermal equilibrium, nuclear transparency and particle production, is discussed. (M.C.K.) [pt

  10. Gravitational waves from spinning eccentric binaries

    Science.gov (United States)

    Csizmadia, Péter; Debreczeni, Gergely; Rácz, István; Vasúth, Mátyás

    2012-12-01

    This paper is to introduce a new software called CBwaves which provides a fast and accurate computational tool to determine the gravitational waveforms yielded by generic spinning binaries of neutron stars and/or black holes on eccentric orbits. This is done within the post-Newtonian (PN) framework by integrating the equations of motion and the spin precession equations, while the radiation field is determined by a simultaneous evaluation of the analytic waveforms. In applying CBwaves various physically interesting scenarios have been investigated. In particular, we have studied the appropriateness of the adiabatic approximation, and justified that the energy balance relation is indeed insensitive to the specific form of the applied radiation reaction term. By studying eccentric binary systems, it is demonstrated that circular template banks are very ineffective in identifying binaries even if they possess tiny residual orbital eccentricity, thus confirming a similar result obtained by Brown and Zimmerman (2010 Phys. Rev. D 81 024007). In addition, by investigating the validity of the energy balance relation we show that, contrary to the general expectations, the PN approximation should not be applied once the PN parameter gets beyond the critical value ˜0.08 - 0.1. Finally, by studying the early phase of the gravitational waves emitted by strongly eccentric binary systems—which could be formed e.g. in various many-body interactions in the galactic halo—we have found that they possess very specific characteristics which may be used to identify these type of binary systems. This paper is dedicated to the memory of our colleague and friend Péter Csizmadia a young physicist, computer expert and one of the best Hungarian mountaineers who disappeared in China’s Sichuan near the Ren Zhong Feng peak of the Himalayas on 23 Oct. 2009. We started to develop CBwaves jointly with Péter a couple of months before he left for China.

  11. Probabilistic seismic history matching using binary images

    Science.gov (United States)

    Davolio, Alessandra; Schiozer, Denis Jose

    2018-02-01

    Currently, the goal of history-matching procedures is not only to provide a model matching any observed data but also to generate multiple matched models to properly handle uncertainties. One such approach is a probabilistic history-matching methodology based on the discrete Latin Hypercube sampling algorithm, proposed in previous works, which was particularly efficient for matching well data (production rates and pressure). 4D seismic (4DS) data have been increasingly included into history-matching procedures. A key issue in seismic history matching (SHM) is to transfer data into a common domain: impedance, amplitude or pressure, and saturation. In any case, seismic inversions and/or modeling are required, which can be time consuming. An alternative to avoid these procedures is using binary images in SHM as they allow the shape, rather than the physical values, of observed anomalies to be matched. This work presents the incorporation of binary images in SHM within the aforementioned probabilistic history matching. The application was performed with real data from a segment of the Norne benchmark case that presents strong 4D anomalies, including softening signals due to pressure build up. The binary images are used to match the pressurized zones observed in time-lapse data. Three history matchings were conducted using: only well data, well and 4DS data, and only 4DS. The methodology is very flexible and successfully utilized the addition of binary images for seismic objective functions. Results proved the good convergence of the method in few iterations for all three cases. The matched models of the first two cases provided the best results, with similar well matching quality. The second case provided models presenting pore pressure changes according to the expected dynamic behavior (pressurized zones) observed on 4DS data. The use of binary images in SHM is relatively new with few examples in the literature. This work enriches this discussion by presenting a new

  12. Full Ionisation In Binary-Binary Encounters With Small Positive Energies

    Science.gov (United States)

    Sweatman, W. L.

    2006-08-01

    Interactions between binary stars and single stars and binary stars and other binary stars play a key role in the dynamics of a dense stellar system. Energy can be transferred between the internal dynamics of a binary and the larger scale dynamics of the interacting objects. Binaries can be destroyed and created by the interaction. In a binary-binary encounter, full ionisation occurs when both of the binary stars are destroyed in the interaction to create four single stars. This is only possible when the total energy of the system is positive. For very small energies the probability of this occurring is very low and it tends towards zero as the total energy tends towards zero. Here the case is considered for which all the stars have equal masses. An asymptotic power law is predicted relating the probability of full ionisation with the total energy when this latter quantity is small. The exponent, which is approximately 2.31, is compared with the results from numerical scattering experiments. The theoretical approach taken is similar to one used previously in the three-body problem. It makes use of the fact that the most dramatic changes in scale and energies of a few-body system occur when its components pass near to a central configuration. The position, and number, of these configurations is not known for the general four-body problem, however, with equal masses there are known to be exactly five different cases. Separate consideration and comparison of the properties of orbits close to each of these five central configurations enables the prediction of the form of the cross-section for full ionisation for the case of small positive total energy. This is the relation between total energy and the probability of total ionisation described above.

  13. Planetary Formation and Dynamics in Binary Systems

    Science.gov (United States)

    Xie, J. W.

    2013-01-01

    As of today, over 500 exoplanets have been detected since the first exoplanet was discovered around a solar-like star in 1995. The planets in binaries could be common as stars are usually born in binary or multiple star systems. Although current observations show that the planet host rate in multiple star systems is around 17%, this fraction should be considered as a lower limit because of noticeable selection effects against binaries in planet searches. Most of the current known planet-bearing binary systems are S-types, meaning the companion star acts as a distant satellite, typically orbiting the inner star-planet system over 100 AU away. Nevertheless, there are four systems with a smaller separation of 20 AU, including the Gamma Cephei, GJ 86, HD 41004, and HD 196885. In addition to the planets in circumprimary (S-type) orbits discussed above, planets in circumbinary (P-type) orbits have been found in only two systems. In this thesis, we mainly study the planet formation in the S-type binary systems. In chapter 1, we first summarize current observational facts of exoplanets both in single-star and binary systems, then review the theoretical models of planet formation, with special attention to the application in binary systems. Perturbative effects from stellar companions render the planet formation process in binary systems even more complex than that in single-star systems. The perturbations from a binary companion can excite planetesimal orbits, and increase their mutual impact velocities to the values that might exceed their escape velocity or even the critical velocity for the onset of eroding collisions. The intermediate stage of the formation process---from planetesimals to planetary embryos---is thus the most problematic. In the following chapters, we investigate whether and how the planet formation goes through such a problematic stage. In chapter 2, we study the effects of gas dissipation on the planetesimals' mutual accretion. We find that in a

  14. Mixed plastics recycling technology

    CERN Document Server

    Hegberg, Bruce

    1995-01-01

    Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.

  15. Compact stars and the evolution of binary systems

    NARCIS (Netherlands)

    van den Heuvel, E.P.J.

    2011-01-01

    The Chandrasekhar limit is of key importance for the evolution of white dwarfs in binary systems and for the formation of neutron stars and black holes in binaries. Mass transfer can drive a white dwarf in a binary over the Chandrasekhar limit, which may lead to a Type Ia supernova (in case of a CO

  16. Mixed ligand chelates of rare earths in aqueous solution

    International Nuclear Information System (INIS)

    Lakhani, S.U.; Thakur, G.S.; Sangal, S.P.

    1981-01-01

    Mixed ligand chelates of the 1:1 trivalent lanthanoids-EDTA, HEDTA and NTA chelates-1, 2-Dihydroxybenzene (Pyrocatechol) have been investigated at 35degC and 0.2 M ionic strength maintained by NaC10 4 . The formation of mixed ligand chelates has been found in all cases. The formation of mixed ligand chelates with EDTA shows the coordination number of lanthanoids to be eight, while the mixed ligand chelates with HEDTA and NTA shows the coordination number to be seven and six respectively. The stability constants of mixed ligand chelates are smaller than the binary complexes. The order of stability constants with respect to primary ligands follows the order NTA>HEDTA>EDTA. With respect to metal ions the stability constants increases with the decrease in ionic radii such as Gd< Er< Yb. (author)

  17. Mixing ratio sensor of alcohol mixed fuel

    Energy Technology Data Exchange (ETDEWEB)

    Miyata, Shigeru; Matsubara, Yoshihiro

    1987-08-07

    In order to improve combustion efficiency of an internal combustion engine using gasoline-alcohol mixed fuel and to reduce harmful substance in its exhaust gas, it is necessary to control strictly the air-fuel ratio to be supplied and the ignition timing and change the condition of control depending upon the mixing ratio of the mixed fuel. In order to detect the mixing ratio of the mixed fuel, the above mixing ratio has so far been detected by casting a ray of light to the mixed fuel and utilizing a change of critical angle associated with the change of the composition of the fluid of the mixed fuel. However, in case when a light emitting diode is used for the light source above, two kinds of sensors are further needed. Concerning the two kinds of sensors above, this invention offers a mixing ratio sensor for the alcohol mixed fuel which can abolish a temperature sensor to detect the environmental temperature by making a single compensatory light receiving element deal with the compensation of the amount of light emission of the light emitting element due to the temperature change and the compensation of the critical angle caused by the temperature change. (6 figs)

  18. Continuous mixing of solids

    NARCIS (Netherlands)

    Raouf, M.S.

    1963-01-01

    The most important literature on theoretical aspects of mixing solids was reviewed.

    Only when the mixed materials showed no segregation it was possible to analyse the mixing process quantitatively. In this case the mixture could be described by the 'χ' Square test. Longitudinal mixing could be

  19. Performance analysis and binary working fluid selection of combined flash-binary geothermal cycle

    International Nuclear Information System (INIS)

    Zeyghami, Mehdi

    2015-01-01

    Performance of the combined flash-binary geothermal power cycle for geofluid temperatures between 150 and 250 °C is studied. A thermodynamic model is developed, and the suitable binary working fluids for different geofluid temperatures are identified from a list of thirty working fluid candidates, consisting environmental friendly refrigerants and hydrocarbons. The overall system exergy destruction and Vapor Expansion Ratio across the binary cycle turbine are selected as key performance indicators. The results show that for low-temperature heat sources using refrigerants as binary working fluids result in higher overall cycle efficiency and for medium and high-temperature resources, hydrocarbons are more suitable. For combined flash-binary cycle, secondary working fluids; R-152a, Butane and Cis-butane show the best performances at geofluid temperatures 150, 200 and 250 °C respectively. The overall second law efficiency is calculated as high as 0.48, 0.55 and 0.58 for geofluid temperatures equal 150, 200 and 250 °C respectively. The flash separator pressure found to has important effects on cycle operation and performance. Separator pressure dictates the work production share of steam and binary parts of the system. And there is an optimal separator pressure at which overall exergy destruction of the cycle achieves its minimum value. - Highlights: • Performance of the combined flash-binary geothermal cycle is investigated. • Thirty different fluids are screened to find the most suitable ORC working fluid. • Optimum cycle operation conditions presented for geofluids between 150 °C and 250 °C. • Refrigerants are more suitable for the ORC at geothermal sources temperature ≤200 °C. • Hydrocarbons are more suitable for the ORC at geothermal sources temperature >200 °C

  20. WHITE-LIGHT FLARES ON CLOSE BINARIES OBSERVED WITH KEPLER

    International Nuclear Information System (INIS)

    Gao, Qing; Xin, Yu; Liu, Ji-Feng; Zhang, Xiao-Bin; Gao, Shuang

    2016-01-01

    Based on Kepler data, we present the results of a search for white light flares on 1049 close binaries. We identify 234 flare binaries, of which 6818 flares are detected. We compare the flare-binary fraction in different binary morphologies (“detachedness”). The result shows that the fractions in over-contact and ellipsoidal binaries are approximately 10%–20% lower than those in detached and semi-detached systems. We calculate the binary flare activity level (AL) of all the flare binaries, and discuss its variations along the orbital period ( P orb ) and rotation period ( P rot , calculated for only detached binaries). We find that the AL increases with decreasing P orb or P rot , up to the critical values at P orb ∼ 3 days or P rot ∼ 1.5 days, and thereafter the AL starts decreasing no matter how fast the stars rotate. We examine the flaring rate as a function of orbital phase in two eclipsing binaries on which a large number of flares are detected. It appears that there is no correlation between flaring rate and orbital phase in these two binaries. In contrast, when we examine the function with 203 flares on 20 non-eclipse ellipsoidal binaries, bimodal distribution of amplitude-weighted flare numbers shows up at orbital phases 0.25 and 0.75. Such variation could be larger than what is expected from the cross section modification.

  1. Tidal effects in twin-degenerate binaries

    International Nuclear Information System (INIS)

    Campbell, C.G.

    1984-01-01

    The tidal velocity field is calculated for an initially non-rotating low mass white dwarf secondary in a twin-degenerate binary. These motions are used to find the tidal torque on the secondary, to first order in the orbital frequency, and an expression is derived for the synchronization time. For a lobe-filling secondary the synchronization time has a weak dependence on the mass and luminosity of the star, and for the binary G61-29 is found to be of the same order as the estimated lifetime of the system. It is emphasized, however, that tidal excitation of non-radial oscillatory modes in the secondary may significantly shorten the synchronization time. (author)

  2. Image Steganalysis with Binary Similarity Measures

    Directory of Open Access Journals (Sweden)

    Kharrazi Mehdi

    2005-01-01

    Full Text Available We present a novel technique for steganalysis of images that have been subjected to embedding by steganographic algorithms. The seventh and eighth bit planes in an image are used for the computation of several binary similarity measures. The basic idea is that the correlation between the bit planes as well as the binary texture characteristics within the bit planes will differ between a stego image and a cover image. These telltale marks are used to construct a classifier that can distinguish between stego and cover images. We also provide experimental results using some of the latest steganographic algorithms. The proposed scheme is found to have complementary performance vis-à-vis Farid's scheme in that they outperform each other in alternate embedding techniques.

  3. EXOSAT and IUE observations of contact binaries

    International Nuclear Information System (INIS)

    Vilhu, O.; Heise, J.; Laboratorium voor Ruimteonderzoek, Utrecht, Netherlands)

    1986-01-01

    EXOSAT observations are reported of the contact binaries W UMa, VW Cep, 44t Boo, XY Leo, and V566 Oph and the detached short-period RS CVn stars ER Vul and HD 209943. Complete X-ray light curves were obtained for W UMa, VW Cep and 44t Boo. Nearly simultaneous IUE observations of VW Cep provide important comparisons of the Mg II emission, the UV continuum, and the FES light curve, pointing to extra hot gas at phase 0.75. The observations indicate that contact binaries have highly structured (in temperature and geometry) and highly variable coronae, not preferentially connected with either of the component stars. The observed dips can be interpreted as due to cool absorbing clouds above localized X-ray emitting regions. For VW Cep, 44t Boo, and XY Leo there is evidence that the neck regions are sites for X-ray-emitting hot gas. 66 references

  4. On the dynamics of binary galaxies

    International Nuclear Information System (INIS)

    Verner, D.A.; Chernin, A.D.

    1987-01-01

    The dynamics of close noncontact binary galaxies is investigated. It is demonsrated that the tidal interaction is ineffective for circularization of galaxy orbits. Nonsphericity of galaxies develops a torque in a binary system. For a pair of elliptical galaxies this torque leads to swinging of the galaxies with respect to the orbital plane (which can be observed as a rotation about the minor axis) and to the excitation of internal degrees of freedom. Besides, this pendulum effect may be effective for elliptical galaxies in clusters due to the presence of the torque produced by a cluster as a whole. In the case of spiral galaxies the torque leads to the precession of their rotational axes. However this effect seems to be too weak to be observable

  5. Memory Vulnerability Diagnosis for Binary Program

    Directory of Open Access Journals (Sweden)

    Tang Feng-Yi

    2016-01-01

    Full Text Available Vulnerability diagnosis is important for program security analysis. It is a further step to understand the vulnerability after it is detected, as well as a preparatory step for vulnerability repair or exploitation. This paper mainly analyses the inner theories of major memory vulnerabilities and the threats of them. And then suggests some methods to diagnose several types of memory vulnerabilities for the binary programs, which is a difficult task due to the lack of source code. The diagnosis methods target at buffer overflow, use after free (UAF and format string vulnerabilities. We carried out some tests on the Linux platform to validate the effectiveness of the diagnosis methods. It is proved that the methods can judge the type of the vulnerability given a binary program.

  6. THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES

    International Nuclear Information System (INIS)

    Brown, Warren R.; Kenyon, Scott J.; Kilic, Mukremin; Gianninas, A.; Allende Prieto, Carlos

    2013-01-01

    We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P ≤ 1 day) binaries. Our sample includes four objects with remarkable log g ≅ 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times 0.9 M ☉ companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.

  7. Detectability of Gravitational Waves from High-Redshift Binaries.

    Science.gov (United States)

    Rosado, Pablo A; Lasky, Paul D; Thrane, Eric; Zhu, Xingjiang; Mandel, Ilya; Sesana, Alberto

    2016-03-11

    Recent nondetection of gravitational-wave backgrounds from pulsar timing arrays casts further uncertainty on the evolution of supermassive black hole binaries. We study the capabilities of current gravitational-wave observatories to detect individual binaries and demonstrate that, contrary to conventional wisdom, some are, in principle, detectable throughout the Universe. In particular, a binary with rest-frame mass ≳10^{10}M_{⊙} can be detected by current timing arrays at arbitrarily high redshifts. The same claim will apply for less massive binaries with more sensitive future arrays. As a consequence, future searches for nanohertz gravitational waves could be expanded to target evolving high-redshift binaries. We calculate the maximum distance at which binaries can be observed with pulsar timing arrays and other detectors, properly accounting for redshift and using realistic binary waveforms.

  8. THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St, Cambridge, MA 02138 (United States); Kilic, Mukremin; Gianninas, A. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019 (United States); Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)

    2013-05-20

    We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P {<=} 1 day) binaries. Our sample includes four objects with remarkable log g {approx_equal} 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have {approx}>0.9 M{sub Sun} companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.

  9. European mixed forests

    DEFF Research Database (Denmark)

    Bravo-Oviedo, Andres; Pretzsch, Hans; Ammer, Christian

    2014-01-01

    Aim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material...... and Methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any...... density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields...

  10. Stochastic simulation of nucleation in binary alloys

    Science.gov (United States)

    L’vov, P. E.; Svetukhin, V. V.

    2018-06-01

    In this study, we simulate nucleation in binary alloys with respect to thermal fluctuations of the alloy composition. The simulation is based on the Cahn–Hilliard–Cook equation. We have considered the influence of some fluctuation parameters (wave vector cutoff and noise amplitude) on the kinetics of nucleation and growth of minority phase precipitates. The obtained results are validated by the example of iron–chromium alloys.

  11. Evaporative lithographic patterning of binary colloidal films.

    Science.gov (United States)

    Harris, Daniel J; Conrad, Jacinta C; Lewis, Jennifer A

    2009-12-28

    Evaporative lithography offers a promising new route for patterning a broad array of soft materials. In this approach, a mask is placed above a drying film to create regions of free and hindered evaporation, which drive fluid convection and entrained particles to regions of highest evaporative flux. We show that binary colloidal films exhibit remarkable pattern formation when subjected to a periodic evaporative landscape during drying.

  12. Digitizing Villanova University's Eclipsing Binary Card Catalogue

    Science.gov (United States)

    Guzman, Giannina; Dalton, Briana; Conroy, Kyle; Prsa, Andrej

    2018-01-01

    Villanova University’s Department of Astrophysics and Planetary Science has years of hand-written archival data on Eclipsing Binaries at its disposal. This card catalog began at Princeton in the 1930’s with notable contributions from scientists such as Henry Norris Russel. During World War II, the archive was moved to the University of Pennsylvania, which was one of the world centers for Eclipsing Binary research, consequently, the contributions to the catalog during this time were immense. It was then moved to University of Florida at Gainesville before being accepted by Villanova in the 1990’s. The catalog has been kept in storage since then. The objective of this project is to digitize this archive and create a fully functional online catalog that contains the information available on the cards, along with the scan of the actual cards. Our group has built a database using a python-powered infrastructure to contain the collected data. The team also built a prototype web-based searchable interface as a front-end to the catalog. Following the data-entry process, information like the Right Ascension and Declination will be run against SIMBAD and any differences between values will be noted as part of the catalog. Information published online from the card catalog and even discrepancies in information for a star, could be a catalyst for new studies on these Eclipsing Binaries. Once completed, the database-driven interface will be made available to astronomers worldwide. The group will also acquire, from the database, a list of referenced articles that have yet to be found online in order to further pursue their digitization. This list will be comprised of references in the cards that were neither found on ADS nor online during the data-entry process. Pursuing the integration of these references to online queries such as ADS will be an ongoing process that will contribute and further facilitate studies on Eclipsing Binaries.

  13. A Bayesian model for binary Markov chains

    Directory of Open Access Journals (Sweden)

    Belkheir Essebbar

    2004-02-01

    Full Text Available This note is concerned with Bayesian estimation of the transition probabilities of a binary Markov chain observed from heterogeneous individuals. The model is founded on the Jeffreys' prior which allows for transition probabilities to be correlated. The Bayesian estimator is approximated by means of Monte Carlo Markov chain (MCMC techniques. The performance of the Bayesian estimates is illustrated by analyzing a small simulated data set.

  14. Unstable mass outflow from a binary system

    Energy Technology Data Exchange (ETDEWEB)

    Nariai, K [Tokyo Univ., Mitaka (Japan). Tokyo Astronomical Observatory; Sugimoto, D

    1976-12-01

    A contact binary system which fills the outer Lagrangian lobe is unstable against the mass loss from the second Lagrangian point. The effect of the mass loss on the remaining system is studied for several typical cases. It is shown that the separation between the components at the periastron decreases with a high rate in most cases; therefore, the system continues to lose mass once gas begins to flow out from the second Lagrangian point.

  15. Minimum degree and density of binary sequences

    DEFF Research Database (Denmark)

    Brandt, Stephan; Müttel, J.; Rautenbach, D.

    2010-01-01

    For d,k∈N with k ≤ 2d, let g(d,k) denote the infimum density of binary sequences (x)∈{0,1} which satisfy the minimum degree condition σ(x+) ≥ k for all i∈Z with xi=1. We reduce the problem of computing g(d,k) to a combinatorial problem related to the generalized k-girth of a graph G which...

  16. Relativistic apsidal motion in eccentric eclipsing binaries

    Czech Academy of Sciences Publication Activity Database

    Wolf, M.; Claret, L.; Kotková, Lenka; Kučáková, Hana; Kocián, R.; Brát, L.; Svoboda, P.; Šmelcer, L.

    2010-01-01

    Roč. 509, January (2010), A18/1-A18/14 ISSN 0004-6361 Grant - others:GA ČR(CZ) GA205/04/2063; GA ČR(CZ) GA205/06/0217 Institutional research plan: CEZ:AV0Z10030501 Keywords : binaries eclipsing Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.410, year: 2010

  17. Guidance for the utility of linear models in meta-analysis of genetic association studies of binary phenotypes.

    Science.gov (United States)

    Cook, James P; Mahajan, Anubha; Morris, Andrew P

    2017-02-01

    Linear mixed models are increasingly used for the analysis of genome-wide association studies (GWAS) of binary phenotypes because they can efficiently and robustly account for population stratification and relatedness through inclusion of random effects for a genetic relationship matrix. However, the utility of linear (mixed) models in the context of meta-analysis of GWAS of binary phenotypes has not been previously explored. In this investigation, we present simulations to compare the performance of linear and logistic regression models under alternative weighting schemes in a fixed-effects meta-analysis framework, considering designs that incorporate variable case-control imbalance, confounding factors and population stratification. Our results demonstrate that linear models can be used for meta-analysis of GWAS of binary phenotypes, without loss of power, even in the presence of extreme case-control imbalance, provided that one of the following schemes is used: (i) effective sample size weighting of Z-scores or (ii) inverse-variance weighting of allelic effect sizes after conversion onto the log-odds scale. Our conclusions thus provide essential recommendations for the development of robust protocols for meta-analysis of binary phenotypes with linear models.

  18. Formation and Evolution of Contact Binaries

    Directory of Open Access Journals (Sweden)

    Peter P. Eggleton

    2012-06-01

    Full Text Available describe a series of processes, including hierarchical fragmentation, gravitational scattering, Kozai cycles within triple systems, tidal friction and magnetic braking, that I believe are responsible for producing the modest but significant fraction of stars that are observed as contact binaries. I also discuss further processes, namely heat transport, mass transport, nuclear evolution, thermal relaxation oscillations, and further magnetic braking with tidal friction, that influence the evolution during contact. The endpoint, for contact, is that the two components merge into a single star, as recently was observed in the remarkable system V1309 Sco. The single star probably throws off some mass and rotates rapidly at first, and then slows by magnetic braking to become a rather inconspicuous but normal dwarf or subgiant. If however the contact binary was part of a triple system originally–as I suggested above was rather likely–then the result could be a widish binary with apparently non-coeval components. There are several such known.

  19. ORBITAL EVOLUTION OF COMPACT WHITE DWARF BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, David L. [Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Bildsten, Lars [Kavli Institute for Theoretical Physics and Department of Physics, Kohn Hall, University of California, Santa Barbara, CA 93106 (United States); Steinfadt, Justin D. R., E-mail: kaplan@uwm.edu, E-mail: bildsten@kitp.ucsb.edu, E-mail: jdrsteinfadt@gmail.com [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106 (United States)

    2012-10-10

    The newfound prevalence of extremely low mass (ELM, M{sub He} < 0.2 M{sub Sun }) helium white dwarfs (WDs) in tight binaries with more massive WDs has raised our interest in understanding the nature of their mass transfer. Possessing small (M{sub env} {approx} 10{sup -3} M{sub Sun }) but thick hydrogen envelopes, these objects have larger radii than cold WDs and so initiate mass transfer of H-rich material at orbital periods of 6-10 minutes. Building on the original work of D'Antona et al., we confirm the 10{sup 6} yr period of continued inspiral with mass transfer of H-rich matter and highlight the fact that the inspiraling direct-impact double WD binary HM Cancri likely has an ELM WD donor. The ELM WDs have less of a radius expansion under mass loss, thus enabling a larger range of donor masses that can stably transfer matter and become a He mass transferring AM CVn binary. Even once in the long-lived AM CVn mass transferring stage, these He WDs have larger radii due to their higher entropy from the prolonged H-burning stage.

  20. Constraining the Statistics of Population III Binaries

    Science.gov (United States)

    Stacy, Athena; Bromm, Volker

    2012-01-01

    We perform a cosmological simulation in order to model the growth and evolution of Population III (Pop III) stellar systems in a range of host minihalo environments. A Pop III multiple system forms in each of the ten minihaloes, and the overall mass function is top-heavy compared to the currently observed initial mass function in the Milky Way. Using a sink particle to represent each growing protostar, we examine the binary characteristics of the multiple systems, resolving orbits on scales as small as 20 AU. We find a binary fraction of approx. 36, with semi-major axes as large as 3000 AU. The distribution of orbital periods is slightly peaked at approx. < 900 yr, while the distribution of mass ratios is relatively flat. Of all sink particles formed within the ten minihaloes, approx. 50 are lost to mergers with larger sinks, and 50 of the remaining sinks are ejected from their star-forming disks. The large binary fraction may have important implications for Pop III evolution and nucleosynthesis, as well as the final fate of the first stars.