Sample records for holomorphically separable complex

  1. Holomorphic embedding of complex curves in spaces of constant holomorphic curvature. (United States)

    Chavel, I; Rauch, H E


    A special case of Wirtinger's theorem asserts that a complex curve (two-dimensional) holomorphically embedded in a Kaehler manifold is a minimal surface. The converse is not necessarily true. Guided by considerations from the theory of moduli of Riemann surfaces, we discover (among other results) sufficient topological and differential-geometric conditions for a minimal (Riemannian) immersion of a 2-manifold in complex projective space with the Fubini-Study metric to be holomorphic.

  2. Holomorphic two-spheres in the complex Grassmann manifold G(k, n)

    Indian Academy of Sciences (India)

    Abstract. In this paper, we study the non-degenerate holomorphic S2 in the complex. Grassmann manifold G(k, n), 2k ≤ n, by the method of moving frame. For a non- degenerate holomorphic one, there exists globally defined positive functions λ1,...,λk on S2. We first show that the holomorphic S2 in G(k, 2k) is totally ...

  3. Holomorphic Dynamical Systems in the Complex Plane: An Introduction

    DEFF Research Database (Denmark)

    Branner, Bodil


    The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points. The paper is the first one in a series of three papers about Holomorphic Dynamics in the Proceedings...

  4. Holomorphic Superspace

    CERN Document Server

    Baulieu, Laurent


    We give a twisted holomorphic superspace description for the super-Yang--Mills theory, using holomophic and antiholomorphic decompositions of twisted spinors. We consider the case of the $\\N=1$ super-Yang--Mills theory in four dimensions. We solve the constraints in two different manners, without and with a prepotential. This might have further application for an holomorphic superspace description of $\\N=1,d=10$ theory. We also explain how the $\\N=1$ and $\\N=2$ holomorphic superspaces are related.

  5. Holomorphic Dynamical Systems

    CERN Document Server

    Guenot, Jacques; Patrizio, Giorgio


    The theory of holomorphic dynamical systems is a subject of increasing interest in mathematics, both for its challenging problems and for its connections with other branches of pure and applied mathematics. This volume collects the Lectures held at the 2008 CIME session on "Holomorphic Dynamical Systems" held in Cetraro, Italy. This CIME Course focused on a number of important topics in the study of discrete and continuous dynamical systems, including both local and global aspects, providing a fascinating introduction to many key problems in current research. The contributions provide an ample description of the phenomena occurring in central themes of holomorphic dynamics such as automorphisms and meromorphic self-maps of projective spaces, of entire maps on complex spaces and holomorphic foliations in surfaces and higher dimensional manifolds, elaborating on the different techniques used and familiarizing readers with the latest findings on current research topics.

  6. Stein manifolds and holomorphic mappings the homotopy principle in complex analysis

    CERN Document Server

    Forstnerič, Franc


    This book, now in a carefully revised second edition, provides an up-to-date account of Oka theory, including the classical Oka-Grauert theory and the wide array of applications to the geometry of Stein manifolds. Oka theory is the field of complex analysis dealing with global problems on Stein manifolds which admit analytic solutions in the absence of topological obstructions. The exposition in the present volume focuses on the notion of an Oka manifold introduced by the author in 2009. It explores connections with elliptic complex geometry initiated by Gromov in 1989, with the Andersén-Lempert theory of holomorphic automorphisms of complex Euclidean spaces and of Stein manifolds with the density property, and with topological methods such as homotopy theory and the Seiberg-Witten theory. Researchers and graduate students interested in the homotopy principle in complex analysis will find this book particularly useful. It is currently the only work that offers a comprehensive introduction to both the Oka t...

  7. Stein Manifolds and Holomorphic Mappings

    CERN Document Server

    Forstneric, Franc


    The main theme of this book is the homotopy principle for holomorphic mappings from Stein manifolds to the newly introduced class of Oka manifolds. This book contains the first complete account of Oka-Grauert theory and its modern extensions, initiated by Mikhail Gromov and developed in the last decade by the author and his collaborators. Included is the first systematic presentation of the theory of holomorphic automorphisms of complex Euclidean spaces, a survey on Stein neighborhoods, connections between the geometry of Stein surfaces and Seiberg-Witten theory, and a wide variety of applicat

  8. Holomorphic curves in loop groups

    Energy Technology Data Exchange (ETDEWEB)

    Guest, M.A.; Pressley, A.N.


    It was observed by Atiyah that there is a correspondence between based gauge equivalence classes of SU/sub n/-instantons over S/sup 4/ of charge d on the one hand, and based holomorphic curves of genus zero in ..cap omega..SU/sub n/ of degree d on the other hand. In this paper we study the parameter space of such holomorphic curves which have the additional property that they lie entirely in the subgroup ..cap omega../sub alg/SU/sub n/ of algebraic loops. We describe a cell decomposition of this parameter space, and compute its complex dimension to be (2n-1)d.

  9. Holomorphic Dynamics and Herman Rings

    DEFF Research Database (Denmark)

    Henriksen, Christian


    Existence theorem for Herman Rings of holomorphic mappings in a certain holomorphic family is given, using quasiconformal mappings. Proofs of topological properties of these Herman rings are given.......Existence theorem for Herman Rings of holomorphic mappings in a certain holomorphic family is given, using quasiconformal mappings. Proofs of topological properties of these Herman rings are given....

  10. Holomorphic Q classes

    CERN Document Server


    The space Q p consists of all holomorphic functions f on the unit disk for which the L^2 area integrals of its derivative against the p-th power of the Green function of the unit disk are uniformly bounded in the variable that survives the integration. It turns out that Q 1 coincides with BMOA, while, for p>1, Q p are just the Bloch space. For p/in (0,1) the Q p furnish an increasing sequence of spaces, each invariant under conformal mappings of the unit disk onto itself, which interpolate between the Dirichlet space and BMOA. This monograph covers a number of important aspects in complex, functional and harmonic analysis. The primary focus is Q p, p/in (0,1), and their equivalent characterizations. Based on the up-to-date results obtained by experts in their respective fields, each of the eight chapters unfolds from the basics to the more complex. The exposition here is rapid-paced and efficient, with proofs and examples.

  11. On 2d TQFTs whose values are holomorphic symplectic varieties


    Moore, Gregory W.; Tachikawa, Yuji


    For simple and simply-connected complex algebraic group G, we conjecture the existence of a functor eta_G from the category of 2-bordisms to the category of holomorphic symplectic varieties with Hamiltonian action, such that gluing of boundaries corresponds to the holomorphic symplectic quotient with respect to the diagonal action of G. We describe various properties of eta_G obtained via string-theoretic analysis. Mathematicians are urged to construct eta_G rigorously.

  12. Resolving curvature singularities in holomorphic gravity

    NARCIS (Netherlands)

    Mantz, C.L.M.; Prokopec, T.|info:eu-repo/dai/nl/326113398


    We formulate a holomorphic theory of gravity and study how the holomorphy symmetry alters the two most important singular solutions of general relativity: black holes and cosmology. We show that typical observers (freely) falling into a holomorphic black hole do not encounter a curvature

  13. Holomorphic blocks in three dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Beem, Christopher [Simons Center for Geometry and Physics, Stony Brook University,Stony Brook, NY 11794-3636 (United States); Dimofte, Tudor [Institute for Advanced Study,Einstein Dr., Princeton, NJ 08540 (United States); Trinity College,Cambridge CB2 1TQ (United Kingdom); Pasquetti, Sara [Department of Mathematics, University of Surrey,Guildford, Surrey, GU2 7XH (United Kingdom)


    We decompose sphere partition functions and indices of three-dimensional N=2 gauge theories into a sum of products involving a universal set of “holomorphic blocks”. The blocks count BPS states and are in one-to-one correspondence with the theory’s massive vacua. We also propose a new, effective technique for calculating the holomorphic blocks, inspired by a reduction to supersymmetric quantum mechanics. The blocks turn out to possess a wealth of surprising properties, such as a Stokes phenomenon that integrates nicely with actions of three-dimensional mirror symmetry. The blocks also have interesting dual interpretations. For theories arising from the compactification of the six-dimensional (2,0) theory on a three-manifold M, the blocks belong to a basis of wavefunctions in analytically continued Chern-Simons theory on M. For theories engineered on branes in Calabi-Yau geometries, the blocks offer a non-perturbative perspective on open topological string partition functions.

  14. Holomorphic anomaly and quantum mechanics (United States)

    Codesido, Santiago; Mariño, Marcos


    We show that the all-orders WKB periods of one-dimensional quantum mechanical oscillators are governed by the refined holomorphic anomaly equations of topological string theory. We analyze in detail the double-well potential and the cubic and quartic oscillators, and we calculate the WKB expansion of their quantum free energies by using the direct integration of the anomaly equations. We reproduce in this way all known results about the quantum periods of these models, which we express in terms of modular forms on the WKB curve. As an application of our results, we study the large order behavior of the WKB expansion in the case of the double well, which displays the double factorial growth typical of string theory.

  15. Lattice-motivated holomorphic nearly perturbative QCD (United States)

    Ayala, César; Cvetič, Gorazd; Kögerler, Reinhart


    Newer lattice results indicate that, in the Landau gauge at low spacelike momenta, the gluon propagator and the ghost dressing function are finite nonzero. This leads to a definition of the QCD running coupling, in a specific scheme, that goes to zero at low spacelike momenta. We construct a running coupling which fulfills these conditions, and at the same time reproduces to a high precision the perturbative behavior at high momenta. The coupling is constructed in such a way that it reflects qualitatively correctly the holomorphic (analytic) behavior of spacelike observables in the complex plane of the squared momenta, as dictated by the general principles of quantum field theories. Further, we require the coupling to reproduce correctly the nonstrange semihadronic decay rate of tau lepton which is the best measured low-momentum QCD observable with small higher-twist effects. Subsequent application of the Borel sum rules to the V + A spectral functions of tau lepton decays, as measured by OPAL Collaboration, determines the values of the gluon condensate and of the V + A six-dimensional condensate, and reproduces the data to a significantly higher precision than the usual \\overline{{MS}} running coupling.

  16. Algebras of holomorphic functions and control theory

    CERN Document Server

    Sasane, Amol


    This accessible, undergraduate-level text illustrates the role of algebras of holomorphic functions in the solution of an important engineering problem: the stabilization of a linear control system. Its concise and self-contained treatment avoids the use of higher mathematics and forms a bridge to more advanced treatments. The treatment consists of two components: the algebraic framework, which serves as the abstract language for posing and solving the problem of stabilization; and the analysis component, which examines properties of specific rings of holomorphic functions. Elementary, self-co

  17. Simultaneous linearization of holomorphic germs in presence of resonances (United States)

    Raissy, Jasmin

    Let f_{1}, ..., f_{m} be m≥ 2 germs of biholomorphisms of C^{n} , fixing the origin, with (df_{1})_{O} diagonalizable and such that f_{1} commutes with f_{h} for any h=2,..., m . We prove that, under certain arithmetic conditions on the eigenvalues of (df_{1})_{O} and some restrictions on their resonances, f_{1}, ..., f_{m} are simultaneously holomorphically linearizable if and only if there exists a particular complex manifold invariant under f_{1}, ..., f_{m} .

  18. Holomorphic Spaces in the Unit Ball of

    Directory of Open Access Journals (Sweden)

    Augusto Guadalupe Miss Paredes


    Full Text Available We introduce the and vector spaces of holomorphic functions defined in the unit ball of , generalizing previous work like Ouyang et al. (1998, Stroethoff (1989, and Choa et al. (1992. Likewise, we characterize those spaces in terms of harmonic majorants as a generalization of Arellano et al. (2000.

  19. Holomorphic Dynamical Systems in the Complex Plane

    DEFF Research Database (Denmark)

    Branner, Bodil


    The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarity between Juliasets of certain quadratic polynomials and the Mandelbrot set....

  20. Holomorphic dynamical systems in the complex plane

    DEFF Research Database (Denmark)

    Branner, Bodil


    The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarities between Julia sets of certain quadratic polynomials and the Madelbrot...

  1. Low Complexity Bayesian Single Channel Source Separation

    DEFF Research Database (Denmark)

    Beierholm, Thomas; Pedersen, Brian Dam; Winther, Ole


    . Simulations with separation of a male and a female speaker using priors trained on the same speakers show comparable performance with the blind separation approach of G.-J. Jang and T.-W. Lee (see NIPS, vol.15, 2003) with a SNR improvement of 4.9 dB for both the male and female speaker. Mixing coefficients...... keeping the complexity low using machine learning and CASA (computational auditory scene analysis) approaches (Jang and Lee, 2003; Roweis, S.T., 2001; Wang, D.L. and Brown, G.J., 1999; Hu, G. and Wang, D., 2003)....

  2. J-holomorphic curves and symplectic topology

    CERN Document Server

    McDuff, Dusa


    The theory of J-holomorphic curves has been of great importance since its introduction by Gromov in 1985. In mathematics, its applications include many key results in symplectic topology. It was also one of the main inspirations for the creation of Floer homology. In mathematical physics, it provides a natural context in which to define Gromov-Witten invariants and quantum cohomology, two important ingredients of the mirror symmetry conjecture. The main goal of this book is to establish the fundamental theorems of the subject in full and rigorous detail. In particular, the book contains comple

  3. Holomorphic Corrections from Wrapped Euclidean Branes

    CERN Document Server

    Petersson, Christoffer


    We discuss how non-perturbative corrections to the four-dimensional effective superpotential are generated by wrapped Euclidean D-branes. It is shown how such terms can be computed and we give a few examples of holomorphic couplings that arise from a D-brane instanton effect in string theory. Some of these instanton configurations give rise to phenomenologically desirable couplings although they do not admit an obvious interpretation in terms of standard gauge theory. This note is based on [R. Argurio, M. Bertolini, G. Ferretti, A. Lerda and C. Petersson, JHEP 0706, 067 (2007) [arXiv:0704.0262 [hep-th

  4. Quantization and non-holomorphic modular forms

    CERN Document Server

    Unterberger, André


    This is a new approach to the theory of non-holomorphic modular forms, based on ideas from quantization theory or pseudodifferential analysis. Extending the Rankin-Selberg method so as to apply it to the calculation of the Roelcke-Selberg decomposition of the product of two Eisenstein series, one lets Maass cusp-forms appear as residues of simple, Eisenstein-like, series. Other results, based on quantization theory, include a reinterpretation of the Lax-Phillips scattering theory for the automorphic wave equation, in terms of distributions on R2 automorphic with respect to the linear action of SL(2,Z).

  5. Holomorphic classification of four-dimensional surfaces in C{sup 3}

    Energy Technology Data Exchange (ETDEWEB)

    Beloshapka, V K [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation); Ezhov, V V [University of Adelaide (Australia); Schmalz, G [University of New England, Armidale (Australia)


    We use the method of model surfaces to study real four-dimensional submanifolds of C{sup 3}. We prove that the dimension of the holomorphic symmetry group of any germ of an analytic four-dimensional manifold does not exceed 5 if this dimension is finite. (There are only two exceptional cases of infinite dimension.) The envelope of holomorphy of the model surface is calculated. We construct a normal form for arbitrary germs and use it to give a holomorphic classification of completely non-degenerate germs. It is shown that the existence of a completely non-degenerate CR-structure imposes strong restrictions on the topological structure of the manifold. In particular, the four-sphere S{sup 4} admits no completely non-degenerate embedding into a three-dimensional complex manifold.

  6. String operator formalism and functional integral in holomorphic representation

    Energy Technology Data Exchange (ETDEWEB)

    Losev, A.; Morozov, A.; Rosly, A.; Shatashvili, S.


    We discuss the relation between the functional integral over open Riemann surfaces and the operator formalism on closed Riemann surfaces. The states in the latter formalism arise in the holomorphic representation of the functional integral.

  7. Holomorphic Embedded Load Flow for autonomous spacecraft power systems Project (United States)

    National Aeronautics and Space Administration — The Holomorphic Embedding Load Flow Method (HELM) is a breakthrough that brings significant advances to the field of power systems. It provides a non-iterative...

  8. Multilevel Atomic Coherent States and Atomic Holomorphic Representation (United States)

    Cao, Chang-Qi; Haake, Fritz


    The notion of atomic coherent states is extended to the case of multilevel atom collective. Based on atomic coherent states, a holomorphic representation for atom collective states and operators is defined. An example is given to illustrate its application.

  9. Spinodal phase separation in complex fluids (United States)

    Schmid, F.; Blossey, R.


    We study the early stages of the phase separation of an amphiphilic system into two fluids, one structured and the other not, in the context of a one-component order-parameter model. A generalization of the Langer — Bar-on — Miller approximation permits the calculation of the time evolution of the structure function in the mixture. Near the structured-fluid side of the coexistence, we find that the spinodal is much more clearly observable and is closer to the binodal than on the unstructured side.

  10. Using Ion Exchange Chromatography to Separate and Quantify Complex Ions (United States)

    Johnson, Brian J.


    Ion exchange chromatography is an important technique in the separation of charged species, particularly in biological, inorganic, and environmental samples. In this experiment, students are supplied with a mixture of two substitution-inert complex ions. They separate the complexes by ion exchange chromatography using a "flash"…

  11. The Schroedinger representation and its relation to the holomorphic representation in linear and affine field theory

    Energy Technology Data Exchange (ETDEWEB)

    Oeckl, Robert [Centro de Ciencias Matematicas, Universidad Nacional Autonoma de Mexico, Campus Morelia, C.P. 58190, Morelia, Michoacan (Mexico)


    We establish a precise isomorphism between the Schroedinger representation and the holomorphic representation in linear and affine field theory. In the linear case, this isomorphism is induced by a one-to-one correspondence between complex structures and Schroedinger vacua. In the affine case we obtain similar results, with the role of the vacuum now taken by a whole family of coherent states. In order to establish these results we exhibit a rigorous construction of the Schroedinger representation and use a suitable generalization of the Segal-Bargmann transform. Our construction is based on geometric quantization and applies to any real polarization and its pairing with any Kaehler polarization.

  12. Remote Voltage Control Using the Holomorphic Embedding Load Flow Method

    DEFF Research Database (Denmark)

    Liu, Chengxi; Qin, Nan; Sun, Kai


    This paper proposes a new remote voltage control approach based on the non-iterative holomorphic embedding load flow method (HELM). A participation factor matrix is applied together with the HELM to distribute reactive power injections among multiple remote reactive power resources such that the ......This paper proposes a new remote voltage control approach based on the non-iterative holomorphic embedding load flow method (HELM). A participation factor matrix is applied together with the HELM to distribute reactive power injections among multiple remote reactive power resources...... such that the approach can remotely control the voltage magnitudes of desired buses. The proposed approach is compared with a conventional Newton-Raphson approach by study cases on the IEEE New England 39-bus system. The results show that the proposed approach achieves a larger convergence region....

  13. Multiplicative Isometries on F-Algebras of Holomorphic Functions

    Directory of Open Access Journals (Sweden)

    Osamu Hatori


    Full Text Available We study multiplicative isometries on the following F-algebras of holomorphic functions: Smirnov class N*(X, Privalov class Np(X, Bergman-Privalov class ANαp(X, and Zygmund F-algebra NlogβN(X, where X is the open unit ball 𝔹n or the open unit polydisk 𝔻n in ℂn.

  14. Holomorphic Hartree-Fock Theory: The Nature of Two-Electron Problems. (United States)

    Burton, Hugh G A; Gross, Mark; Thom, Alex J W


    We explore the existence and behavior of holomorphic restricted Hartree-Fock (h-RHF) solutions for two-electron problems. Through algebraic geometry, the exact number of solutions with n basis functions is rigorously identified as 1/2(3n - 1), proving that states must exist for all molecular geometries. A detailed study on the h-RHF states of HZ (STO-3G) then demonstrates both the conservation of holomorphic solutions as geometry or atomic charges are varied and the emergence of complex h-RHF solutions at coalescence points. Using catastrophe theory, the nature of these coalescence points is described, highlighting the influence of molecular symmetry. The h-RHF states of HHeH2+ and HHeH (STO-3G) are then compared, illustrating the isomorphism between systems with two electrons and two electron holes. Finally, we explore the h-RHF states of ethene (STO-3G) by considering the π electrons as a two-electron problem and employ NOCI to identify a crossing of the lowest energy singlet and triplet states at the perpendicular geometry.

  15. Improved Method of Blind Speech Separation with Low Computational Complexity

    Directory of Open Access Journals (Sweden)

    Kazunobu Kondo


    a frame-wise spectral soft mask method based on an interchannel power ratio of tentative separated signals in the frequency domain. The soft mask cancels the transfer function between sources and separated signals. A theoretical analysis of selection criteria and the soft mask is given. Performance and effectiveness are evaluated via source separation simulations and a computational estimate, and experimental results show the significantly improved performance of the proposed method. The segmental signal-to-noise ratio achieves 7 [dB] and 3 [dB], and the cepstral distortion achieves 1 [dB] and 2.5 [dB], in anechoic and reverberant conditions, respectively. Moreover, computational complexity is reduced by more than 80% compared with unmodified FDICA.

  16. Bicomplex holomorphic functions the algebra, geometry and analysis of bicomplex numbers

    CERN Document Server

    Luna-Elizarrarás, M Elena; Struppa, Daniele C; Vajiac, Adrian


    The purpose of this book is to develop the foundations of the theory of holomorphicity on the ring of bicomplex numbers. Accordingly, the main focus is on expressing the similarities with, and differences from, the classical theory of one complex variable. The result is an elementary yet comprehensive introduction to the algebra, geometry and analysis of bicomplex numbers. Around the middle of the nineteenth century, several mathematicians (the best known being Sir William Hamilton and Arthur Cayley) became interested in studying number systems that extended the field of complex numbers. Hamilton famously introduced the quaternions, a skew field in real-dimension four, while almost simultaneously James Cockle introduced a commutative four-dimensional real algebra, which was rediscovered in 1892 by Corrado Segre, who referred to his elements as bicomplex numbers. The advantages of commutativity were accompanied by the introduction of zero divisors, something that for a while dampened interest in this subject. ...

  17. analytic sets and extension of holomorphic maps of positive ...

    Indian Academy of Sciences (India)


    For all (w, w′) ∈ graph(F) ∩ (U1 × U′. 1), F(Qw) ⊂ Q′ w′ . This means that any branch of F maps any point from Qw to Q′ w′ for any point w′ ∈ F(w). Recall that if f : Ω → CN is a holomorphic mapping and M ⊂ ∂Ω, then the cluster set of f at p ∈ M is the set of accumulation points of (f(zj))j, where (zj)j is a sequence ...

  18. Normal forms and linearization of holomorphic dilation type semigroups in several variables


    Bracci, Filippo; Elin, Mark; Shoikhet, David


    In this paper we study commuting families of holomorphic mappings in $\\mathbb{C}^n$ which form abelian semigroups with respect to their real parameter. Linearization models for holomorphic mappings are been used in the spirit of Schr\\"oder's classical functional equation.

  19. Topological and Functional Properties of Some F-Algebras of Holomorphic Functions

    Directory of Open Access Journals (Sweden)

    Romeo Meštrović


    Full Text Available Let Np  (11, we also consider the countably normed Fréchet algebra Fp of holomorphic functions on D which is the Fréchet envelope of the space Np. Notice that the spaces Fp and Np have the same topological duals. In this paper, we give a characterization of bounded subsets of the spaces Fp and weakly bounded subsets of the spaces Np with p>1. If (Fp∗ denotes the strong dual space of Fp and Npw∗ denotes the space Sp of complex sequences γ={γn}n satisfying the condition γn=Oexp-cn1/(p+1, equipped with the topology of uniform convergence on weakly bounded subsets of Np, then we prove that Fp∗=Npw∗ both set theoretically and topologically. We prove that for each p>1  Fp is a Montel space and that both spaces Fp and (Fp∗ are reflexive.

  20. Separating Random Oracle Proofs from Complexity Theoretic Proofs

    DEFF Research Database (Denmark)

    Nielsen, Jesper Buus


    We show that there exists a natural protocol problem which has a simple solution in the random-oracle (RO) model and which has no solution in the complexity-theoretic (CT) model, namely the problem of constructing a non-interactive communication protocol secure against adaptive adversaries a.......k.a. non-interactive non-committing encryption. This separation between the models is due to the so-called programability of the random oracle. We show this by providing a formulation of the RO model in which the oracle is not programmable, and showing that in this model, there does not exist non...

  1. Generalized N=2 Topological Amplitudes and Holomorphic Anomaly Equation

    CERN Document Server

    Antoniadis, I; Narain, K S; Sokatchev, E


    In arXiv:0905.3629 we described a new class of N=2 topological amplitudes that depends both on vector and hypermultiplet moduli. Here we find that this class is actually a particular case of much more general topological amplitudes which appear at higher loops in heterotic string theory compactified on K3 x T^2. We analyze their effective field theory interpretation and derive particular (first order) differential equations as a consequence of supersymmetry Ward identities and the 1/2-BPS nature of the corresponding effective action terms. In string theory the latter get modified due to anomalous world-sheet boundary contributions, generalizing in a non-trivial way the familiar holomorphic and harmonicity anomalies studied in the past. We prove by direct computation that the subclass of topological amplitudes studied in arXiv:0905.3629 forms a closed set under these anomaly equations and that these equations are integrable.

  2. Holomorphic variables in magnetized brane models with continuous Wilson lines

    CERN Document Server

    Camara, Pablo G; Dudas, Emilian


    We analyze the action of the target-space modular group in toroidal type IIB orientifold compactifications with magnetized D-branes and continuous Wilson lines. The transformation of matter fields agree with that of twisted fields in heterotic compactifications, constituting a check of type I/heterotic duality. We identify the holomorphic N = 1 variables for these compactifications. Matter fields and closed string moduli are both redefined by open string moduli. The redefinition of matter fields can be read directly from the perturbative Yukawa couplings, whereas closed string moduli redefinitions are obtained from D-brane instanton superpotential couplings. The resulting expressions reproduce and generalize, in the presence of internal magnetic fields, previous results in the literature.

  3. Isomorphisms on Weighed Banach Spaces of Harmonic and Holomorphic Functions

    Directory of Open Access Journals (Sweden)

    Enrique Jordá


    Full Text Available For an arbitrary open subset U⊂ℝd or U⊆ℂd and a continuous function v:U→]0,∞[ we show that the space hv0(U of weighed harmonic functions is almost isometric to a (closed subspace of c0, thus extending a theorem due to Bonet and Wolf for spaces of holomorphic functions Hv0(U on open sets U⊂ℂd. Inspired by recent work of Boyd and Rueda, we characterize in terms of the extremal points of the dual of hv0(U when hv0(U is isometric to a subspace of c0. Some geometric conditions on an open set U⊆ℂd and convexity conditions on a weight v on U are given to ensure that neither Hv0(U nor hv0(U are rotund.

  4. Fifteen papers in complex analysis

    CERN Document Server

    Aizenberg, L A; Degtyar', P V; Gindikin, S G; Gaidis, Ya Yu


    The papers in this volume range over a variety of topics in complex analysis, including holomorphic and entire functions, integral representations, the local theory of residues, complex manifolds, singularities, and CR structures.

  5. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  6. Nonlinear holomorphic supersymmetry, Dolan-Grady relations and Onsager algebra

    Energy Technology Data Exchange (ETDEWEB)

    Klishevich, Sergey M. E-mail:; Plyushchay, Mikhail S. E-mail:


    Recently, it was noticed by us that the nonlinear holomorphic supersymmetry of order n is contained in N, n>1 (n-HSUSY) has an algebraic origin. We show that the Onsager algebra underlies n-HSUSY and investigate the structure of the former in the context of the latter. A new infinite set of mutually commuting charges is found which, unlike those from the Dolan-Grady set, include the terms quadratic in the Onsager algebra generators. This allows us to find the general form of the superalgebra of n-HSUSY and fix it explicitly for the cases of n=2,3,4,5,6. The similar results are obtained for a new, contracted form of the Onsager algebra generated via the contracted Dolan-Grady relations. As an application, the algebraic structure of the known 1D and 2D systems with n-HSUSY is clarified and a generalization of the construction to the case of nonlinear pseudo-supersymmetry is proposed. Such a generalization is discussed in application to some integrable spin models and with its help we obtain a family of quasi-exactly solvable systems appearing in the PT-symmetric quantum mechanics.

  7. On F-Algebras Mp  (1Holomorphic Functions

    Directory of Open Access Journals (Sweden)

    Romeo Meštrović


    Full Text Available We consider the classes Mp (1holomorphic functions on the open unit disk in the complex plane. These classes are in fact generalizations of the class M introduced by Kim (1986. The space Mp equipped with the topology given by the metric ρp defined by ρp(f,g=f-gp=∫02π‍logp1+Mf-gθdθ/2π1/p, with f,g∈Mp and Mfθ=sup0⩽r<1⁡f(reiθ, becomes an F-space. By a result of Stoll (1977, the Privalov space Np (1

  8. Holomorphic couplings in non-perturbative string compactifications

    Energy Technology Data Exchange (ETDEWEB)

    Klevers, Denis Marco


    In this thesis we present an analysis of several aspects of four-dimensional, non-perturbative N = 1 compactifications of string theory. Our focus is on the study of brane dynamics and their effective physics as encoded in the holomorphic couplings of the low-energy N=1 effective action, most prominently the superpotential W. The thesis is divided into three parts. In part one we derive the effective action of a spacetime-filling D5-brane in generic Type IIB Calabi-Yau orientifold compactifications. In the second part we invoke tools from string dualities, namely from F-theory, heterotic/F-theory duality and mirror symmetry, for a more elaborate study of the dynamics of (p, q) 7-branes and heterotic five-branes. In this context we demonstrate exact computations of the complete perturbative effective superpotential, both due to branes and background fluxes. Finally, in the third part we present a novel geometric description of five-branes in Type IIB and heterotic M-theory Calabi-Yau compactifications via a non-Calabi-Yau threefold Z{sub 3}, that is canonically constructed from the original five-brane and Calabi-Yau threefold Z{sub 3} via a blow-up. We exploit the use of the blow-up threefold Z{sub 3} as a tool to derive open-closed Picard-Fuchs differential equations, that govern the complete effective brane and flux superpotential. In addition, we present first evidence to interpret Z{sub 3} as a flux compactification dual to the original five-brane by defining an SU(3)-structure on Z{sub 3}, that is generated dynamically by the five-brane backreaction. (orig.)

  9. Resurgent Transseries and the Holomorphic Anomaly: Nonperturbative Closed Strings in Local CP2

    CERN Document Server

    Couso-Santamaría, Ricardo; Schiappa, Ricardo; Vonk, Marcel


    The holomorphic anomaly equations describe B-model closed topological strings in Calabi-Yau geometries. Having been used to construct perturbative expansions, it was recently shown that they can also be extended past perturbation theory by making use of resurgent transseries. These yield formal nonperturbative solutions, showing integrability of the holomorphic anomaly equations at the nonperturbative level. This paper takes such constructions one step further by working out in great detail the specific example of topological strings in the mirror of the local CP2 toric Calabi-Yau background, and by addressing the associated (resurgent) large-order analysis of both perturbative and multi-instanton sectors. In particular, analyzing the asymptotic growth of the perturbative free energies, one finds contributions from three different instanton actions related by Z_3 symmetry, alongside another action related to the Kahler parameter. Resurgent transseries methods then compute, from the extended holomorphic anomal...

  10. BPS state counting using wall-crossing, holomorphic anomalies and modularity

    Energy Technology Data Exchange (ETDEWEB)

    Wotschke, Thomas


    In this thesis we examine the counting of BPS states using wall-crossing, holomorphic anomalies and modularity. We count BPS states that arise in two setups: multiple M5-branes wrapping P x T{sup 2}, where P denotes a divisor inside a Calabi-Yau threefold and topological string theory on elliptic Calabi-Yau threefolds. The first setup has a dual description as type IIA string theory via a D4-D2-D0 brane system. Furthermore it leads to two descriptions depending on the size of P and T{sup 2} relative to each other. For the case of a small divisor P this setup is described by the (0,4) Maldacena-Strominger-Witten conformal field theory of a black hole in M-theory and for the case of small T{sup 2} the setup can by described by N=4 topological Yang-Mills theory on P. The BPS states are counted by the modified elliptic genus, which can be decomposed into a vector-valued modular form that provides the generating function for the BPS invariants and a Siegel-Narain theta function. In the first part we discuss the holomorphic anomaly of the modified elliptic genus for the case of two M5-branes and divisors with b{sup +}{sub 2}(P)=1. Due to the wall-crossing effect the change in the generating function is captured by an indefinite theta function, which is a mock modular form. We use the Kontsevich-Soibelman wall-crossing formula to determine the jumps in the modified elliptic genus. Using the regularisation procedure for mock modular forms of Zwegers, modularity can be restored at the cost of holomorphicity. We show that the non-holomorphic completion is due to bound states of single M5-branes. At the attractor point in the moduli space we prove the holomorphic anomaly equation, which is compatible with the holomorphic anomaly equations observed in the context of N=4 Yang-Mills theory on P{sup 2} and E-strings on a del Pezzo surface. We calculate the generating functions of BPS invariants for the divisors P{sup 2}, F{sub 0}, F{sub 1} and the del Pezzo surface dP{sub 8} and

  11. Holomorphic Hartree-Fock Theory: The Nature of Two-Electron Problems


    Burton, Hugh G. A.; Gross, Mark; Thom, Alex J. W.


    We explore the existence and behaviour of holomorphic restricted Hartree-Fock (h-RHF) solutions for two-electron problems. Through algebraic geometry, the exact number of solutions with $n$ basis functions is rigorously identified as $\\frac{1}{2}(3^n - 1)$, proving that states must exist for all molecular geometries. A detailed study on the h-RHF states of HZ (STO-3G) then demonstrates both the conservation of holomorphic solutions as geometry or atomic charges are varied and the emergence of...

  12. Oracle separation of complexity classes and lower bounds for perceptrons solving separation problems (United States)

    Vereshchagin, N. K.


    In the first part of the paper we prove that, relative to a random oracle, the class NP contains infinite sets having no infinite Co-NP-subsets (Co-NP-immune sets). In the second part we prove that perceptrons separating Boolean matrices in which each row contains at least one 1 from matrices in which many rows (say 99% of them) have no 1's must have either large size or large order. This result partially strengthens the "one-in-a-box"' theorem of Minsky and Papert [16] which states that perceptrons of small order cannot decide if every row of a given Boolean matrix has a 1. As a corollary, we prove that AM {}\\cap{}Co-AM {}\

  13. Actinides(3)/lanthanides(3) separation by nano-filtration assisted by complexation; Separation actinides(3)lanthanides(3) par nanofiltration assistee par complexation

    Energy Technology Data Exchange (ETDEWEB)

    Sorin, A


    In France, one of the research trend concerning the reprocessing of spent nuclear fuel consists to separate selectively the very radio-toxic elements with a long life to be recycled (Pu) or transmuted (Am, Cm, Np). The aim of this thesis concerns the last theme about actinides(III)/lanthanides(III) separation by a process of nano-filtration assisted by complexation. Thus, a pilot of tangential membrane filtration was designed and established in a glove box at the ATALANTE place of CEA-Marcoule. Physico-chemical characterisation of the Desal GH membrane (OSMONICS), selected to carry out actinides(III)/lanthanides(III) separation, was realized to determine the zeta potential of the active layer and its resistance to ionizing radiations. Moreover, a parametric study was also carried out to optimize the selectivity of complexation, and the operating conditions of complex retention (influences of the transmembrane pressure, solute concentration, tangential velocity and temperature). Finally, the separation of traces of Am(III) contained in a mixture of lanthanides(III), simulating the real load coming from a reprocessing cycle, was evaluated with several chelating agents such as poly-amino-carboxylic acids according to the solution acidity and the [Ligand]/[Cation(III)] ratio. (author)

  14. Exploring charge and color breaking vacuum in non-holomorphic MSSM (United States)

    Beuria, Jyotiranjan; Dey, Abhishek


    Non-Holomorphic MSSM (NHSSM) shows various promising features that are not easily obtained in MSSM. However, the additional Non-Holomorphic (NH) trilinear interactions that attribute to the interesting phenomenological features, also modify the effective scalar potential of the model significantly. We derive analytic constraints involving trilinear parameters A t ' and A b ' that exclude global charge and color breaking minima (CCB). Since the analytic constraints are obtained considering specific directions in the multi-dimensional field space, we further probe the applicability of these constraints by exhaustive scan over NH parameter space with two different regimes of tan β and delineate the nature of metastability by considering vacuum expectation values for third generation squarks. We adhere to a natural scenario by fixing Higgsino mass parameter ( μ) to a low value and estimate the allowed ranges of NH trilinear parameters by considering vacuum stability and observed properties of Higgs as the determining criteria.

  15. Equivariant Holomorphic Morse Inequalities; 2, Torus and Non-Abelian Group Actions

    CERN Document Server

    Wu, S


    We extend the equivariant holomorphic Morse inequalities of circle actions to cases with torus and non-Abelian group actions on holomorphic vector bundles over Kahler manifolds and show the necessity of the Kahler condition. For torus actions, there is a set of inequalities for each choice of action chambers specifying directions in the Lie algebra of the torus. We apply the results to invariant line bundles over toric manifolds. If the group is non-Abelian, there is in addition an action of the Weyl group on the fixed-point set of its maximal torus. The sum over the fixed points can be rearranged into sums over the Weyl group (having incorporated the character of the isotropy representation on the fiber) and over its orbits.

  16. Influence of DNA-dye complex stability on separation resolution in microchip electrophoresis. (United States)

    Lo, Roger C; Joffe, Aaron M


    Different markers have been used to label DNA for sample detection in gel electrophoresis. Intercalating dyes, (e.g., YOYO) have been widely used to label DNA for sample detection, because they do not require the use of radioisotopes, covalent attachment or enzyme reactions. The labeling of DNA fragments can be achieved by simply mixing solutions of the intercalating dye and DNA sample. However, the separation quality of DNA labeled with intercalating dyes is greatly influenced by the buffer used, which affects the DNA-dye complex stability. In this study, we investigated the effects of DNA-dye complex stability on separation resolution of dsDNA migrating in a photopolymerized polyacrylamide gel by measuring mobility and dispersion coefficients on a microfluidic chip and comparing predicted separation resolution under different dye and buffer conditions. We found that a buffer containing tetrapentylammonium (NPe(4)(+)) yielded better separation resolution than the frequently used TBE buffer on our microchip electrophoresis system.

  17. Physicochemical basis of the ion-exchange separation of gold cyanide complexes (United States)

    Kononova, O. N.; Kononov, Yu. S.


    The mechanism of the separation of gold cyanide complexes is discussed, along with ion exchanger selection, selectivity, elution, and industrial applications. The ion-exchange mechanism for the sorption of gold cyanide complexes is established, and a criterion is suggested for selecting the anion exchanger for their extraction (specifically, the p K a of the anion exchanger). The selectivity of the sorption of gold cyanide complexes by anion exchangers with rarely distributed ionogenic groups is demonstrated. A procedure for the elution of gold cyanide complexes using alkaline solutions is developed.

  18. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation (United States)

    Lilga, Michael A.; Hallen, Richard T.


    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the produce gas from coal gasification processes.

  19. Enantiomeric separation of iridium (III) complexes using HPLC chiral stationary phases based on amylose derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hee Eun; Seo, Na Hyeon; Hyun, Myung Ho [Dept. of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan (Korea, Republic of)


    Cyclometalated iridium (III) complexes formed with three identical cyclometalating (C-N) ligands (homoleptic) or formed with two cyclometalating (C-N) ligands and one ancillary (LX) ligand (heteroleptic) have been known as highly phosphorescent materials and, thus, they have been utilized as efficient phosphorescent dopants in organic light emitting diodes (OLEDs) 1–3 or as effective phosphorescent chemosensors. 4–7 Cylometalated iridium (III) complexes are chiral compounds consisting of lambda (Λ, left-handed) and delta (Δ, right-handed) isomers. Racemic cyclometa- lated iridium (III) complexes emit light with no net polarization, but optically active cyclometalated iridium (III) complexes emit circularly polarized light. 8,9 Circularly polarized light can be used in various fields including highly efficient three dimensional electronic devices, photo nic devices for optical data storage, biological assays, and others. 8,9 In order to obtain optically active cylometalated iridium (III) complexes and to determine the enantiomeric composition of optically active cylometalated iridium (III) complexes, liquid chromatogr aphic enantiomer separation method on chiral stationary phases (CSPs) has been used. For example, Okamoto and coworkers first reported the high performance liquid chromatographic (HPLC) direct enantiomeric separation of two homoleptic cylometalated iridium (III) complexes on immobilized amylose tris(3,5- dimethylphenylcarbamate) (Chiralpak IA), coated cellulose tris(3,5-dimethylphenylcarbamate) (Chiralc el OD), and coated cellulose tris(4-methylbenzoate) (Chiralce l OJ). 10 Supercritical fluid chromatography (SFC) was also used by Bernhard and coworkers for the enantiomeric separation of cylometalated iridium (III) complexes on coated amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak AD-H). 8 However, the general use of the HPLC method for the direct enantiomeric separation of homoleptic.

  20. Separation of trap-collected adults of Anopheles atropos from species of the quadrimaculatus complex. (United States)

    Reinert, J F


    The presence of a moderate- to large-sized patch of dark scales on the anterior surface of the fore coxa of Anopheles atropos can be used to separate this species from species of the Quadrimaculatus Complex collected in coastal areas of the United States. Identification of specimens is possible even if they have been collected in traps and are rubbed and faded.

  1. Separation of gas mixtures by supported complexes. Final report, 1 October 1982-30 September 1984

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, D.A.; Hallen, R.T.; Lilga, M.A.


    This final report covers research performed to identify and demonstrate advantageous procedures for the chemical separation of gases, such as CO, CO/sub 2/, and H/sub 2/, from medium-Btu gas mixtures by use of supported complexes. Three complexes were chosen for rapid gas uptake and selectivity at 25/sup 0/C from among a group of 22 coordination complexes synthesized during this program. The three complexes showed considerable selectivity toward individual gases. For instance, Pd/sub 2/(dpm)/sub 2/Cl/sub 2/ or (Pd-Pd), rapidly bound carbon monoxide from solution. This complex could be regenerated, with the carbon monoxide reversibly removed, by warming to 40/sup 0/C. The presence of other gases, such as carbon dioxide, oxygen, nitrogen, hydrogen, ethylene, or acetylene, had no effect upon the rapid uptake of carbon monoxide or its removal. Such selectivity was also noted with Ru(CO)/sub 2/(PPh/sub 3/)/sub 3/, biscarbonyltris(triphenylphosphine)ruthenium. Although this complex bound hydrogen, carbon monoxide, and oxygen in solution, the hydrogen was taken up twice as fast as carbon monoxide and seven times faster than oxygen. These gases could be removed from the complex with mild heat or decreased pressure. Crystalline Rh(OH)(CO)(PPh/sub 3/)/sub 2/, hydroxocarbonylbis(triphenylphosphine)rhodium, rapidly bound carbon dioxide; the complex was regenerated at 50/sup 0/C under reduced pressure. The rapid uptake of carbon dioxide by this complex was not changed in the presence of oxygen. In general the three selected crystalline or solvent dissolved complexes performed well in the absence of polymeric support. The stability and favorable kinetics of the three complexes suggest that they could be utilized in a solution system for gas separation (Conceptual Analyses and Preliminary Economics). Further, these complexes appear to be superb candidates as transport agents for facilitated-transport, membrane systems

  2. Separation and characterization of nanoparticles in complex food and environmental samples by field-flow fractionation

    DEFF Research Database (Denmark)

    Kammer, Frank von der; Legros, Samuel; Hofmann, Thilo


    has been applied for separation of various types of NP (e.g., organic macromolecules, and carbonaceous or inorganic NPs) in different types of media (e.g., natural waters, soil extracts or food samples).FFF can be coupled to different types of detectors that offer additional information...... sample preparation, field-flow fractionation (FFF) is one of the most promising techniques to achieve relevant characterization.The objective of this review is to present the current status of FFF as an analytical separation technique for the study of NPs in complex food and environmental samples. FFF...... constituents in the samples require contradictory separation conditions. The potential of FFF analysis should always be evaluated bearing in mind the impact of the necessary sample preparation, the information that can be retrieved from the chosen detection systems and the influence of the chosen separation...

  3. Separation of glycols from dilute aqueous solutions via complexation with boronic acids

    Energy Technology Data Exchange (ETDEWEB)

    Randel, L.A.; King, C.J.


    This work examines methods of separating low molecular weight glycols from dilute aqueous solution. Extraction into conventional solvents is generally not economical, since, in the literature reviewed, distribution ratios for the two- to four-carbon glycols are all less than one. Distribution ratios can be increased, however, by incorporating into the organic phase an extracting agent that will complex with the solute of interest. The extracting agent investigated in this work is 3-nitrophenylboronic acid (NPBA). NPBA, a boric acid derivative, reversibly complexes with many glycols. The literature on complexation of borate and related compounds with glycols, including mechanistic data, measurement techniques, and applications to separation processes, provides information valuable for designing experiments with NPBA and is reviewed herein. 88 refs., 15 figs., 24 tabs.

  4. New water soluble phosphonate and polycarboxylate complexants for enhanced f element separations

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L.; Rickert, P.G.; Lessmann, E.P.; Mendoza, M.D.; Feil, J.F.; Sullivan, J.C.


    While lipophilic extractant molecules and ion exchange polymeric materials are clearly essential to efficient separation of metal ions by solvent extraction or ion exchange, the most difficult separations often could not be accomplished without the use of water soluble complexants. This report focuses on recent developments in design, synthesis and characterization of phosphonic acid and polycarboxylic acid ligands for enhanced f element separations. Emphasis is on the basic solution chemistry and crystal structures of complexes of the f elements with selected amino-derivatives of methanediphosphonic acid and with tetrahydrofuran-2,3,4,5-tetracarboxylic acid. The former series of compounds exhibit high affinity for lanthanides and actinides in acidic solutions. The latter ligand exhibits an unusual (and very useful) ``anti-selectivity`` for uranyl ion in a solvent extraction process, which permits efficient separation of uranyl from more radioactive components of nuclear wastes. Most of the observed effects can be explained through examination of the structure of the ligand, and comparison of the spectroscopic and thermodynamic parameters for complexation of various metal ions.

  5. Application of holomorphic functions in two and higher dimensions

    CERN Document Server

    Gürlebeck, Klaus; Sprößig, Wolfgang


    This book presents applications of hypercomplex analysis to boundary value and initial-boundary value problems from various areas of mathematical physics. Given that quaternion and Clifford analysis offer natural and intelligent ways to enter into higher dimensions, it starts with quaternion and Clifford versions of complex function theory including series expansions with Appell polynomials, as well as Taylor and Laurent series. Several necessary function spaces are introduced, and an operator calculus based on modifications of the Dirac, Cauchy-Fueter, and Teodorescu operators and different decompositions of quaternion Hilbert spaces are proved. Finally, hypercomplex Fourier transforms are studied in detail. All this is then applied to first-order partial differential equations such as the Maxwell equations, the Carleman-Bers-Vekua system, the Schrödinger equation, and the Beltrami equation. The higher-order equations start with Riccati-type equations. Further topics include spatial fluid flow problems, ima...

  6. Large N expansion of convergent matrix integrals, holomorphic anomalies, and background independence (United States)

    Eynard, B.


    We propose an asymptotic expansion formula for matrix integrals, including oscillatory terms (derivatives of theta-functions) to all orders. This formula is heuristically derived from the analogy between matrix integrals, and formal matrix models (combinatorics of discrete surfaces), after summing over filling fractions. The whole oscillatory series can also be resummed into a single theta function. We also remark that the coefficients of the theta derivatives, are the same as those which appear in holomorphic anomaly equations in string theory, i.e. they are related to degeneracies of Riemann surfaces. Moreover, the expansion presented here, happens to be independent of the choice of a background filling fraction.

  7. Characterization of silver nanoparticles-alginate complexes by combined size separation and size measurement techniques. (United States)

    António, Diana C; Cascio, Claudia; Gilliland, Douglas; Nogueira, António J A; Rossi, François; Calzolai, Luigi


    The detection and quantification of nanoparticles is a complex issue due to the need to combine "classical" identification and quantification of the constituent material, with the accurate determination of the size of submicrometer objects, usually well below the optical diffraction limit. In this work, the authors show that one of the most used analytical methods for silver nanoparticles, asymmetric flow field-flow fractionation, can be strongly influenced by the presence of dissolved organic matter (such as alginate) and lead to potentially misleading results. The authors explain the anomalies in the separation process and show a very general way forward based on the combination of size separation and size measurement techniques. This combination of techniques results in more robust AF4-based methods for the sizing of silver nanoparticles in environmental conditions and could be generally applied to the sizing of nanoparticles in complex matrices.

  8. Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Tina Kuo Fung [Univ. of California, Berkeley, CA (United States)


    The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25°C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB-, with all complexes containing only one NPB- per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation with B(OH)4- (aq.), i.e. the complexation constants increase with increasing number of -OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB-) at higher concentrations. The -OH group on the NPB- which is left uncomplexed after one solute molecule had bound to the other two -OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA+ can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB-. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.

  9. Long-lived photoinduced charge separation for solar cell applications in supramolecular complexes of multi-metalloporphyrins and fullerenes. (United States)

    Fukuzumi, Shunichi; Ohkubo, Kei


    Monomers, dimers, trimers, dendrimers and oligomers of metalloporphyrins form supramolecular complexes with fullerene derivatives via electrostatic interactions, π-π interactions and coordination bonds. Photoexcitation of the supramolecular complexes resulted in photoinduced electron transfer from the porphyrin moiety to the fullerene moiety to produce the charge-separated states as revealed by laser flash photolysis measurements. The rate constants of photoinduced charge separation and charge recombination in supramolecular complexes of multi-metalloporphyrins and fullerenes were also determined by laser flash photolysis measurements and the results depending on the number of porphyrins in the supramolecular complexes are discussed in terms of efficiency of photoinduced energy transfer and charge separation as well as the lifetimes of charge-separated states. The photoelectrochemical performances of solar cells composed of supramolecular complexes of monomers, dimers, dendrimers and oligomers of metalloporphyrins with fullerenes are compared in relation to the rate constants of photoinduced charge separation and charge recombination.

  10. Optimal synthesis and design of extractive distillation systems for bioethanol separation: From simple to complex columns

    DEFF Research Database (Denmark)

    Errico, M.; Rong, B. G.; Tola, G.


    separation techniques are today available, distillation is up to now the frontrunner technology in most of the plants. In particular extractive distillation is considered as an energy efficient method to produce pure ethanol overcoming the purity limitations imposed by the water-ethanol azeotrope...... considering the total condenser and reboiler duty as energy index. The capital costs and the solvent consumption are also taken into account in the final selection. Among all the complex configurations considered the two-column sequence can reduce the capital cost above 10% compared to the best simple column......Bioethanol has been considered as a green fuel and a valid alternative to reduce the dependence on fossil distillates. The development of an optimal separation process is considered as a key element in the design of an efficient process able to be cost effective and competitive. Despite many...

  11. Holomorphic Dynamics

    DEFF Research Database (Denmark)

    Willumsen, Pia B.N.

    In this thesis we study the structure of the boundary of the cubic connectedness locus viewed from the escape locus; i.e. the limiting behaviour of stretching rays.We prove that the stretching ray through a polynomial P with no parabolic fixed point of multiplier one accumulates a cubic polynomia...... with a parabolic cycle. We give an example of a non-vanishing cubic ground wind. It follows that the wring operator is discontinuous in degree three.......In this thesis we study the structure of the boundary of the cubic connectedness locus viewed from the escape locus; i.e. the limiting behaviour of stretching rays.We prove that the stretching ray through a polynomial P with no parabolic fixed point of multiplier one accumulates a cubic polynomial...... with one parabolic fixed point of multiplier one, the other fixed point repelling, and each critical point in the parabolic basin or in a (super)-attracting basin only if a critical point of P belongs to a fixed ray of the filled Julia set of P. This applies to the locus of cubic polynomials with both...

  12. Separation of Alkyne Enantiomers by Chiral Column HPLC Analysis of Their Cobalt-Complexes

    Directory of Open Access Journals (Sweden)

    Qiaoyun Liu


    Full Text Available Separation of the enantiomers of new chiral alkynes in strategic syntheses and bioorthogonal studies is always problematic. The chiral column high-performance liquid chromatography (HPLC method in general could not be directly used to resolve such substrates, since the differentiation of the alkyne segment with the other alkane/alkene segment is not significant in the stationary phase, and the alkyne group is not a good UV chromophore. Usually, a pre-column derivatization reaction with a tedious workup procedure is needed. Making use of easily-prepared stable alkyne-cobalt-complexes, we developed a simple and general method by analyzing the in situ generated cobalt-complex of chiral alkynes using chiral column HPLC. This new method is especially suitable for the alkynes without chromophores and other derivable groups.

  13. Phase separation induced by ladder-like polymer-polymer complexation. (United States)

    Nakamura, Issei; Shi, An-Chang


    Polymer-polymer complexation in solvent is studied using an extension of the self-consistent field theory. The model polymers are capable of forming ladder-like duplex structures. The duplex formation occurs with an abrupt change of entropy, resulting in a first-order transition. Moreover, the complexation can be stabilized by solvent-polymer interactions, instead of the usual specific binding interactions. Various types of unconventional phase diagrams are predicted. For example, phase separation with decreasing χ-parameter between duplex polymer and solvent can be induced, leading to a lower critical solution temperature (LCST) behavior. Multiphase coexistence points at which two, three, or four phases coexist are also obtained. Under certain conditions a homogeneous phase becomes unstable when the polymer chain length is decreased, in contrast to the standard Flory-Huggins theory.

  14. Software and hardware complex for research and management of the separation process (United States)

    Borisov, A. P.


    The article is devoted to the development of a program for studying the operation of an asynchronous electric drive using vector-algorithmic switching of windings, as well as the development of a hardware-software complex for controlling parameters and controlling the speed of rotation of an asynchronous electric drive for investigating the operation of a cyclone. To study the operation of an asynchronous electric drive, a method was used in which the average value of flux linkage is found and a method for vector-algorithmic calculation of the power and electromagnetic moment of an asynchronous electric drive feeding from a single-phase network is developed, with vector-algorithmic commutation, and software for calculating parameters. The software part of the complex allows to regulate the speed of rotation of the motor by vector-algorithmic switching of transistors or, using pulse-width modulation (PWM), set any engine speed. Also sensors are connected to the hardware-software complex at the inlet and outlet of the cyclone. The developed cyclone with an inserted complex allows to receive high efficiency of product separation at various entrance speeds. At an inlet air speed of 18 m / s, the cyclone’s maximum efficiency is achieved. For this, it is necessary to provide the rotational speed of an asynchronous electric drive with a frequency of 45 Hz.

  15. Extraction chromatographic separations of tantalum and tungsten from hafnium and complex matrix constituents. (United States)

    Snow, Mathew S; Finck, Martha R; Carney, Kevin P; Morrison, Samuel S


    Tantalum (Ta), hafnium (Hf), and tungsten (W) analyses from complex matrices require high purification of these analytes from each other and major/trace matrix constituents, however, current state-of-the-art Ta/Hf/W separations rely on traditional anion exchange approaches that show relatively similar distribution coefficient (Kd) values for each element. This work reports an assessment of three commercially available extraction chromatographic resins (TEVA, TRU, and UTEVA) for Ta/Hf/W separations. Batch contact studies show differences in Ta/Hf and Ta/W Kd values of up to 106 and 104 (respectively), representing an improvement of a factor of 100 and 300 in Ta/Hf and Ta/W Kd values (respectively) over AG1×4 resin. Variations in the Kd values as a function of HCl concentration for TRU resin show that this resin is well suited for Ta/Hf/W separations, with Ta/Hf, Ta/W, and W/Hf Kd value improvements of 10, 200, and 30 (respectively) over AG1×4 resin. Analyses of digested soil samples (NIST 2710a) using TRU resin and tandem TEVA-TRU columns demonstrate the ability to achieve extremely high purification (>99%) of Ta and W from each other and Hf, as well as enabling very high purification of Ta and W from the major and trace elemental constituents present in soils using a single chromatographic step. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Extraction chromatographic separations of tantalum and tungsten from hafnium and complex matrix constituents

    Energy Technology Data Exchange (ETDEWEB)

    Snow, Mathew S.; Finck, Martha R.; Carney, Kevin P.; Morrison, Samuel S.


    Ta, Hf, and W analyses from complex matrices (including environmental samples) require high purification of these analytes from each other and major/trace matrix constituents, however, current state-of-the-art Ta/Hf/W separations rely on traditional anion exchange approaches that suffer from relatively similar distribution coefficient (Kd) values for these analytes. This work reports assessment of three commercially available extraction chromatographic resins (TEVA, TRU, and UTEVA) for Ta/Hf/W separations. Batch contact studies show differences in Ta/W,Hf Kd values of up to 106, representing an improvement of a factor of 100 and 300 in Ta/Hf and Ta/W Kd values (respectively) over AG1x4 resin. Variations in the Kd values as a function of HCl concentration for TRU resin show that this resin is well suited for Ta/Hf/W separations, with Ta/Hf, Ta/W, and W/Hf Kd value improvements of 10, 200, and 30 (respectively) over AG1x4 resin. Finally, analyses of digested soil samples (NIST 2710a) using TRU resin and tandem TEVA-TRU columns demonstrate the ability to achieve extremely high purification (>99%) of Ta and W from each other and Hf, as well as enabling very high purification of Ta and W from the major and trace elemental constituents present in soils, using a single chromatographic step.

  17. Microfluidic separation coupled to mass spectrometry for quantification of peanut allergens in a complex food matrix. (United States)

    Sayers, Rebekah L; Gethings, Lee A; Lee, Victoria; Balasundaram, Anuradha; Johnson, Philip J; Marsh, Justin A; Wallace, Antonietta; Brown, Helen; Rogers, Adrian; Langridge, James I; Mills, E N Clare


    Peanut is an important food allergen but cannot currently be reliably detected and quantified in processed foods at low levels. Three mg protein/Kg is increasingly being used as a reference dose above which precautionary allergen labeling (PAL) is applied to food products. Two exemplar matrices (chocolate dessert and chocolate bar) were prepared and incurred at 0, 3, 10 or 50 mg/Kg peanut protein using a commercially available lightly roasted peanut flour ingredient. After simple buffer extraction employing an acid labile detergent, multiple reaction monitoring (MRM) experiments were used to assess matrix effects on detection of a set of seven peptide targets derived from peanut allergens using either conventional or microfluidic chromatographic separation prior to mass spectrometry. Microfluidic separation provided greater sensitivity and increased ionisation efficiency at low levels. Individual monitored transitions were detected in consistent ratios across the dilution series performed, independent of matrix. The peanut protein content of each sample was then determined using ELISA and the optimised MRM method. Whilst other peptide targets were detected with three transitions at the 50 mg/Kg peanut protein level in both matrices, only Arah2(Q6PSU2)147-155 could quantify reliably, and only in the chocolate dessert at 10 mg/Kg peanut protein. Recoveries were consistent with ELISA analysis returning around 30-50% of the incurred dose. MS coupled with microfluidic separation shows great promise as a complementary analytical tool for allergen detection and quantification in complex foods using simple extraction methodology.

  18. Online Voltage Stability Assessment for Load Areas Based on the Holomorphic Embedding Method

    DEFF Research Database (Denmark)

    Liu, Chengxi; Wang, Bin; Hu, Fengkai


    be calculated based on online state estimation on the entire load area and a measurement-based equivalent for the external system. The HEM employs a power series to calculate an accurate Power-Voltage (P-V) curve at each load bus and accordingly evaluates the voltage stability margin considering load variations......This paper proposes an online steady-state voltage stability assessment scheme to evaluate the proximity to voltage collapse at each bus of a load area. Using a non-iterative holomorphic embedding method (HEM) with a proposed physical germ solution, an accurate loading limit at each load bus can...... and then demonstrated on a load area of the Northeast Power Coordinating Council (NPCC) 48-generator, 140-bus power system....

  19. Rational points, rational curves, and entire holomorphic curves on projective varieties

    CERN Document Server

    Gasbarri, Carlo; Roth, Mike; Tschinkel, Yuri


    This volume contains papers from the Short Thematic Program on Rational Points, Rational Curves, and Entire Holomorphic Curves and Algebraic Varieties, held from June 3-28, 2013, at the Centre de Recherches Mathématiques, Université de Montréal, Québec, Canada. The program was dedicated to the study of subtle interconnections between geometric and arithmetic properties of higher-dimensional algebraic varieties. The main areas of the program were, among others, proving density of rational points in Zariski or analytic topology on special varieties, understanding global geometric properties of rationally connected varieties, as well as connections between geometry and algebraic dynamics exploring new geometric techniques in Diophantine approximation.

  20. Localisation on Sasaki-Einstein manifolds from holomorphic functions on the cone

    Energy Technology Data Exchange (ETDEWEB)

    Schmude, Johannes [Department of Physics, Universidad de Oviedo, Avda. Calvo Sotelo 18, 33007, Oviedo (Spain)


    We study super Yang-Mills theories on five-dimensional Sasaki-Einstein manifolds. Using localisation techniques, we find that the contribution from the vector multiplet to the perturbative partition function can be calculated by counting holomorphic functions on the associated Calabi-Yau cone. This observation allows us to use standard techniques developed in the context of quiver gauge theories to obtain explicit results for a number of examples; namely S{sup 5}, T{sup 1,1}, Y{sup 7,3}, Y{sup 2,1}, Y{sup 2,0}, and Y{sup 4,0}. We find complete agreement with previous results obtained by Qiu and Zabzine using equivariant indices except for the orbifold limits Y{sup p,0} with p>1.

  1. Final summarizing report on Grant DE-SC0001014 "Separation of Highly Complex Mixtures by Two-dimension Liquid Chromatography"

    Energy Technology Data Exchange (ETDEWEB)

    Guiochon, Georges [Univ. of Tennessee, Knoxville, TN (United States)


    The goal of our research was a fundamental investigation of methods available for the coupling of two separate chromatographic separations that would considerably enhance the individual separation power of each of these two separations. This gain arises from the combination of two independent retention mechanisms, one of them separating the components that coelute on the other column, making possible the separation of many more compounds in a given time. The two separation mechanisms used must be very different. This is possible because many retention mechanisms are available, using different kinds of molecular interactions, hydrophobic or hydrophilic interactions, polar interactions, hydrogen bonding, complex formation, ionic interactions, steric exclusion. Two methods can be used, allowing separations to be performed in space (spreading the bands of sample components on a plate covered with stationary phase layer) or in time (eluting the sample components through a column and detecting the bands leaving the column). Both offer a wide variety of possible combinations and were studied.

  2. Violation of the rectus complex is not a contraindication to component separation for abdominal wall reconstruction. (United States)

    Garvey, Patrick B; Bailey, Chad M; Baumann, Donald P; Liu, Jun; Butler, Charles E


    Component separation (CS) is an effective technique for reconstructing complex abdominal wall defects. Violation of the rectus abdominis complex is considered a contraindication for CS, but we hypothesized that patients have similar outcomes with or without rectus complex violation. We retrospectively studied all consecutive patients who underwent CS for abdominal wall reconstruction during 8 years and compared outcomes of patients with and without rectus violation. Primary outcomes measures included complications and hernia recurrence. Logistic regression analysis identified potential associations between patient, defect, and reconstructive characteristics and surgical outcomes. One hundred sixty-nine patients were included: 115 (68%) with and 54 (32%) without rectus violation. Mean follow-up was 21.3 ± 14.5 months. Patient and defect characteristics were similar, except for the rectus violation group having a higher body mass index. Overall complication rates were similar in the violation (24.3%) and nonviolation (24.0%) groups, as were the respective rates of recurrent hernia (7.8% vs 9.2%; p = 0.79), abdominal bulge (3.5% vs 5.6%; p = 0.71), skin dehiscence (20.0% vs 22.2%; p = 0.74), skin necrosis (6.1% vs 3.7%; p = 0.72), cellulitis (7.8% vs 9.2%; p = 0.75), and abscess (12.3% vs 9.2%; p = 0.58). Regression analysis demonstrated body mass index to be the only factor predictive of complications. CS surgical outcomes were similar whether or not the rectus complex was violated. To our knowledge, this study is the first to evaluate the effects of rectus violation on surgical outcomes in CS patients. Surgeons should not routinely avoid CS when the rectus complex is violated. Copyright © 2012 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Efficient charge separation in Li(+) @C60 supramolecular complexes with electron donors. (United States)

    Kawashima, Yuki; Ohkubo, Kei; Fukuzumi, Shunichi


    Lithium-ion-encapsulated fullerene (Li(+) @C60 ) exhibits greatly enhanced reactivity in photoinduced electron-transfer reduction with electron donors compared with pristine C60 . The enhanced reactivity of Li(+) @C60 results from the more positive one-electron reduction potential of Li(+) @C60 (+0.14 V versus a standard calomel electrode (SCE)) than that of C60 (-0.43 V versus SCE), whereas the reorganization energy of electron transfer of Li(+) @C60 (1.01 eV) becomes larger than that of C60 (0.73 eV) because of the change in electrostatic interactions of encapsulated Li(+) upon electron transfer. Li(+) @C60 can form strong supramolecular complexes with various anionic electron donors through electrostatic interactions. Li(+) @C60 can also form strong supramolecular π complexes with various electron donors, such as cyclic porphyrin dimers, corannulene, and crown ether fused monopyrrolotetrathiafulvalenes. Photoinduced electron transfer from electron donors to Li(+) @C60 afforded long-lived charge-separated states of supramolecular complexes between electron donors and Li(+) @C60 . A photoelectrochemical solar cell composed of supramolecular nanoclusters of Li(+) @C60 and zinc sulfonated meso-tetraphenylporphyrin exhibits significant enhancement in the photoelectrochemical performance than that of the reference system containing only a single component. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Low complexity underdetermined blind source separation system architecture for emerging remote healthcare applications. (United States)

    Mopuri, Suresh; Reddy, P Sreenivasa; Ch, Karthik; Prasad, A Siva; Acharyya, Amit; Ramakrishna, V Siva


    In this paper, we have proposed a low complexity architecture for the Under-determined Blind Source Separation (UBSS) algorithm targeting remote healthcare applications. UBSS algorithm, departing from the typical BSS convention-equal number of the sources and sensors present, which is of tremendous interest in the field of Biomedical signal processing especially for remote health care applications. Since such applications are constrained by the on-chip area and power consumption limitation due to the battery backup, a low complexity architecture needs to be formulated. In this paper, firstly we have introduced UBSS architecture, followed by the identification of the most computationally intensive module N-point Discrete Hilbert Transform (DHT) and finally proposed a low complexity DHT architecture design to make the entire UBSS architecture suitable for such resource constrained applications. The proposed DHT architecture implementation and experimental comparison results show that the proposed design saves 50.28%, 48.40% and 46.27% on-chip area and 53.25%, 48.01% and 45.95% power consumption when compared to the state of the art method for N = 32, 64 and 128 respectively. Furthermore the proposed DHT architecture works for N = 2m point, but the state of art architecture works for N = 4m point, where m is an integer.

  5. Holomorphic two-spheres in complex Grassmann manifold G(2,4)

    Indian Academy of Sciences (India)

    is still denoted by {ωAB}). They are skew-Hermitian, i.e.. ωAB + ¯ωBA ... function defined on U, and θ the unitary co-frame field restricted on U. Suppose that g satisfies dg ≡ gϕ mod θ,. (2.13) where ϕ is ... where ξ, η are positive functions, ξ2 + η2 = 1, and θ is the unitary co-frame with respect to the induced metric. Taking the ...

  6. Modified components separation technique: experience treating large, complex ventral hernias at a University Hospital. (United States)

    Torregrosa-Gallud, A; Sancho Muriel, J; Bueno-Lledó, J; García Pastor, P; Iserte-Hernandez, J; Bonafé-Diana, S; Carreño-Sáenz, O; Carbonell-Tatay, F


    An increasing number of patients have large or complex abdominal wall defects. Component separation technique (CST) is a very effective method for reconstructing complex midline abdominal wall defects in a manner that restores innervated muscle function without excessive tension. Our goal is to show our results by a modified CST for treating large ventral hernias. A total of 351 patients with complex ventral hernias have been treated over a 10-year period. Pre- and postoperative CT scans were performed in all patients. All ventral hernias were W3, according to the EHS classification 1. We analyzed demographic variables, co-morbidities, hernia characteristics, operative, and postoperative variables. One hundred and seventy patients (48.4%) were men; the average age of the study population was 51.6 ± 23.2 years with an average BMI of 32.3 ± 1.3. The hernia was located in the midline in 321 cases (91.5%) versus the flank in 30 (8.5%). In 45 patients, preoperative botulinum toxin (BT) and progressive pneumoperitoneum (PPP) were needed due to giant hernia defects when the VIH/VAC ratio was >20%. Postoperative complications related to the surgical site were seroma (35.1%), hematoma (9.1%), infection (7.2%), and wound necrosis (8.8%). Complications related to the repair were evisceration in 3 patients (1.1%), small bowel fistula in 4 patients (1.5%), 11 cases of mesh infection (2.9%), and abdominal compartment syndrome (ACS) in 2 patients. There were 29 hernia recurrences (8.2%) with a mean follow-up of 31.6 ± 8.1 months. The modified CST is an effective strategy for managing complex ventral hernias that enables primary fascial closure with low rates of morbidity and hernia recurrence.

  7. Copper Recovery from Yulong Complex Copper Oxide Ore by Flotation and Magnetic Separation (United States)

    Han, Junwei; Xiao, Jun; Qin, Wenqing; Chen, Daixiong; Liu, Wei


    A combined process of flotation and high-gradient magnetic separation was proposed to utilize Yulong complex copper oxide ore. The effects of particle size, activators, Na2S dosage, LA (a mixture of ammonium sulfate and ethylenediamine) dosage, activating time, collectors, COC (a combination collector of modified hydroxyl oxime acid and xanthate) dosage, and magnetic intensity on the copper recovery were investigated. The results showed that 74.08% Cu was recovered by flotation, while the average grade of the copper concentrates was 21.68%. Another 17.34% Cu was further recovered from the flotation tailing by magnetic separation at 0.8 T. The cumulative recovery of copper reached 91.42%. The modifier LA played a positive role in facilitating the sulfidation of copper oxide with Na2S, and the combined collector COC was better than other collectors for the copper flotation. This technology has been successfully applied to industrial production, and the results are consistent with the laboratory data.

  8. Global skin friction diagnostics: The GLOF technique and measurements of complex separated flows (United States)

    Woodiga, Sudesh A.

    This work describes the application of the global luminescent oil film skin friction meter to quantitative global skin friction diagnostics of complex separated flows. The development of this technique is based on the relationship between the oil film thickness and luminescent intensity of a luminescent oil film. The projected thin oil film equation is given to relate the normalized luminescent intensity with skin friction. The variational formulation with a smoothness constraint on skin friction is proposed to obtain a snap shot solution from two consecutive images for a relative skin friction field. A complete skin friction field is reconstructed through superposition of a sequence of snap shot solutions. A refinement is implemented for this technique focused on data reduction simplification and robustness, luminescent oil formulation, UV excitation and oil film application. This is complemented by a systematic study with emphasis on parametric analysis of data reduction variables such as spatial resolution, time step, Lagrange multiplier, image file format and image filtering. A number of separated flows were also investigated---a low aspect ratio NACA0012 rectangular wing at different angles of attack, wing-body junction flow and delta wings at different angles of attack, yaw and roll. Detailed analysis of the complex skin friction topology of each test case was carried out along with topological constraint analysis using the Poincare-Bendixson index formula. The conservation law given by the Poincare-Bendixson index formula for the number of isolated singular points and boundary switch points in a region enclosed by a penetrable boundary is utilized as a general approach in analyzing the topological features of the skin friction fields. A systematic approach was developed to map skin friction vectors from the two dimensional image plane to a three dimensional model surface in the object space. Combined surface pressure and global skin friction measurements

  9. Separation of drug stereoisomers by the formation of. beta. -cyclodextrin inclusion complexes

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, D.W.; Ward, T.J.; Armstrong, R.D.; Beesley, T.E.


    For many drugs, only racemic mixtures are available for clinical use. Because different stereoisomers of drugs often cause different physiological responses, the use of pure isomers could elicit more exact therapeutic effects. Differential complexation of a variety of drug stereoisomers by immobilized ..beta..-cyclodextrin was investigated. Chiral recognition and racemic resolution were observed with a number of compounds from such clinically useful classes as ..beta..-blockers, calcium-channel blockers, sedative hypnotics, antihistamines, anticonvulsants, diuretics, and synthetic opiates. Separation of the diastereomers of the cardioactive and antimalarial cinchona alkaloids and of two antiestrogens was demonstrated as well. Three dimensional projections of ..beta..-cyclodextrin complexes of propanol, which is resolved by this technique, and warfarin, which is not, are compared. These studies have improved the understanding and application of the chiral interactions of ..beta..-cyclodextrin, and they have demonstrated a means to measure optical purity and to isolate or produce pure enantiomers of drugs. In addition, this highly specific technique could also be used in the pharmacological evaluation of enantiometric drugs. 27 references, 3 figures, 2 tables.

  10. Complex macrophase-separated nanostructure induced by microphase separation in binary blends of lamellar diblock copolymer thin films. (United States)

    Zhang, Jianqi; Posselt, Dorthe; Smilgies, Detlef-M; Perlich, Jan; Kyriakos, Konstantinos; Jaksch, Sebastian; Papadakis, Christine M


    The nanostructures of thin films spin-coated from binary blends of compositionally symmetric polystyrene-b-polybutadiene (PS-b-PB) diblock copolymer having different molar masses are investigated by means of atomic force microscopy (AFM) and grazing-incidence small-angle X-ray scattering (GISAXS) after spin-coating and after subsequent solvent vapor annealing (SVA). In thin films of the pure diblock copolymers having high or low molar mass, the lamellae are perpendicular or parallel to the substrate, respectively. The as-prepared binary blend thin films feature mainly perpendicular lamellae in a one-phase state, indicating that the higher molar mass diblock copolymer dominates the lamellar orientation. The lamellar thickness decreases linearly with increasing volume fraction of the low molar mass diblock copolymer. After SVA, well-defined macrophase-separated nanostructures appear, which feature parallel lamellae near the film surface and perpendicular ones in the bulk. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Complex Analysis

    CERN Document Server

    Stein, Elias M


    With this second volume, we enter the intriguing world of complex analysis. From the first theorems on, the elegance and sweep of the results is evident. The starting point is the simple idea of extending a function initially given for real values of the argument to one that is defined when the argument is complex. From there, one proceeds to the main properties of holomorphic functions, whose proofs are generally short and quite illuminating: the Cauchy theorems, residues, analytic continuation, the argument principle.With this background, the reader is ready to learn a wealth of additional m

  12. In situ magnetic separation of antibody fragments from Escherichia coli in complex media (United States)


    Background In situ magnetic separation (ISMS) has emerged as a powerful tool to overcome process constraints such as product degradation or inhibition of target production. In the present work, an integrated ISMS process was established for the production of his-tagged single chain fragment variable (scFv) D1.3 antibodies (“D1.3”) produced by E. coli in complex media. This study investigates the impact of ISMS on the overall product yield as well as its biocompatibility with the bioprocess when metal-chelate and triazine-functionalized magnetic beads were used. Results Both particle systems are well suited for separation of D1.3 during cultivation. While the triazine beads did not negatively impact the bioprocess, the application of metal-chelate particles caused leakage of divalent copper ions in the medium. After the ISMS step, elevated copper concentrations above 120 mg/L in the medium negatively influenced D1.3 production. Due to the stable nature of the model protein scFv D1.3 in the biosuspension, the application of ISMS could not increase the overall D1.3 yield as was shown by simulation and experiments. Conclusions We could demonstrate that triazine-functionalized beads are a suitable low-cost alternative to selectively adsorb D1.3 fragments, and measured maximum loads of 0.08 g D1.3 per g of beads. Although copper-loaded metal-chelate beads did adsorb his-tagged D1.3 well during cultivation, this particle system must be optimized by minimizing metal leakage from the beads in order to avoid negative inhibitory effects on growth of the microorganisms and target production. Hereby, other types of metal chelate complexes should be tested to demonstrate biocompatibility. Such optimized particle systems can be regarded as ISMS platform technology, especially for the production of antibodies and their fragments with low stability in the medium. The proposed model can be applied to design future ISMS experiments in order to maximize the overall product yield

  13. Research on magnetic separation for complex nickel deep removal and magnetic seed recycling. (United States)

    Qiu, Yiqin; Xiao, Xiao; Ye, Ziwei; Guan, Zhijie; Sun, Shuiyu; Ren, Jie; Yan, Pingfan


    This study investigated the deep removal of complex nickel from simulated wastewater using magnetic separation and magnetic seed recycling. Nano-magnetite (Fe 3 O 4 ) was used as the magnetic seed. The flocculant applied was N,N-bis-(dithiocarboxy) ethanediamine (EDTC), a highly efficient heavy metal chelating agent included in dithiocarbamate (DTC). Important investigated parameters included hydraulic retention time, magnetic seed dosage, and magnetic field strength. The study also explored the magnetic flocculation mechanism involved in the reaction. The result indicated that the residual Ni concentration was reduced to less than 0.1 mg/L from the initial concentration of 50 mg/L under optimal conditions. Magnetic seed recovery reached 76.42% after a 3-h stirring period; recycled magnetic seeds were analyzed using scanning electron microscope (SEM) and X-ray diffraction (XRD). The zeta potential results illustrated that magnetic seeds firmly combined with flocs when the pH ranged from 6.5 to 7.5 due to the electrostatic attraction. When the pH was less than 7, magnetic seeds and EDTC were also combined due to electrostatic attraction. Particle size did affect microfloc size; it decreased microfloc size and increased floc volume through magnetic seed loading. The effective binding sites between flocs and magnetic seeds increased when adding the magnetic seeds. This led the majority of magnetic flocs to be integrated with the magnetic seeds, which served as a nucleus to enhance the flocculation property and ultimately improve the nickel complex removal rate.

  14. Holomorphic field realization of SH{sup c} and quantum geometry of quiver gauge theories

    Energy Technology Data Exchange (ETDEWEB)

    Bourgine, Jean-Emile [INFN Bologna, Università di Bologna,Via Irnerio 46, 40126 Bologna (Italy); Matsuo, Yutaka [Department of Physics, The University of Tokyo,Hongo 7-3-1, Bunkyo-ku, Tokyo (Japan); Zhang, Hong [Department of Physics and Center for Quantum Spacetime (CQUeST),Sogang University,35 Baekbeom-ro, Mapo-gu, Seoul 04107 (Korea, Republic of)


    In the context of 4D/2D dualities, SH{sup c} algebra, introduced by Schiffmann and Vasserot, provides a systematic method to analyse the instanton partition functions of N=2 supersymmetric gauge theories. In this paper, we rewrite the SH{sup c} algebra in terms of three holomorphic fields D{sub 0}(z), D{sub ±1}(z) with which the algebra and its representations are simplified. The instanton partition functions for arbitrary N=2 super Yang-Mills theories with A{sub n} and A{sub n}{sup (1)} type quiver diagrams are compactly expressed as a product of four building blocks, Gaiotto state, dilatation, flavor vertex operator and intertwiner which are written in terms of SH{sup c} and the orthogonal basis introduced by Alba, Fateev, Litvinov and Tarnopolskiy. These building blocks are characterized by new conditions which generalize the known ones on the Gaiotto state and the Carlsson-Okounkov vertex. Consistency conditions of the inner product give algebraic relations for the chiral ring generating functions defined by Nekrasov, Pestun and Shatashvili. In particular we show the polynomiality of the qq-characters which have been introduced as a deformation of the Yangian characters. These relations define a second quantization of the Seiberg-Witten geometry, and, accordingly, reduce to a Baxter TQ-equation in the Nekrasov-Shatashvili limit of the Omega-background.

  15. Complex variables a physical approach with applications and Matlab

    CERN Document Server

    Krantz, Steven G


    PREFACEBASIC IDEAS Complex ArithmeticAlgebraic and Geometric PropertiesThe Exponential and ApplicationsHOLOMORPHIC AND HARMONIC FUNCTIONS Holomorphic FunctionsHolomorphic and Harmonic Functions Real and Complex Line Integrals Complex DifferentiabilityThe LogarithmTHE CAUCHY THEORY The Cauchy Integral TheoremVariants of the Cauchy Formula The Limitations of the Cauchy FormulaAPPLICATIONS OF THE CAUCHY THEORY The Derivatives of a Holomorphic FunctionThe Zeros of a Holomorphic FunctionISOLATED SINGULARITIES Behavior near an Isolated SingularityExpansion around Singular PointsExamples of Laurent ExpansionsThe Calculus of ResiduesApplications to the Calculation of IntegralsMeromorphic FunctionsTHE ARGUMENT PRINCIPLE Counting Zeros and PolesLocal Geometry of Functions Further Results on Zeros The Maximum PrincipleThe Schwarz LemmaTHE GEOMETRIC THEORY The Idea of a Conformal Mapping Mappings of the DiscLinear Fractional Transformations The Riemann Mapping Theorem Conformal Mappings of AnnuliA Compendium of Useful Co...

  16. Separation of Highly Complex Mixtures by Two-Dimension Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Georges Guiochon


    This report summarizes the progress made on the title project during the grant period. We developed a new classification of two-dimensional separations based on the observation that separations can be made in time or in space. Thus, two-dimensional separations can be made in time×time, space×space, space×time, or time×space. The two successive separations must use two different modes of chromatography that afford uncorrelated or weakly correlated patterns of retention factors for the components of the samples analyzed. Our attention was mainly focused on the separation of protein digests, particularly, on those of the digests of myoglobin and bovine serum albumin as model systems and extremely efficient temporal separations were developed. We also designed and constructed new instruments to carry out space×space separations (True Bidimensional Chromatography, HPLC2 or spacial separations) and time×space separations (a new hybrid combination of a temporal and a spacial separation that we designed).

  17. Exponential Separations for One-Way Quantum Communication Complexity, with Applications to Cryptography

    NARCIS (Netherlands)

    D. Gavinsky; J. Kempe; I. Kerenidis; R. Raz; R. M. de Wolf (Ronald); D.S. Johnson; U. Feige


    textabstractWe give an exponential separation between one-way quantum and classical communication protocols for two partial Boolean functions, both of which are variants of the Boolean Hidden Matching Problem of Bar-Yossef et al. Earlier such an exponential separation was known only for a

  18. Separation of complex mixtures of amino acids for biorefinery applications using electrodialysis

    NARCIS (Netherlands)

    Kattan Readi, O.M.; Girones nogue, Miriam; Nijmeijer, Dorothea C.


    The potential of electrodialysis (ED) for the separation of amino acids (zwitterionic molecules that exhibit a specific charge behavior dependent on pH) has been demonstrated in the past. However, even though successful for the separation of specific amino acids, ED is not applicable for the

  19. L² approaches in several complex variables development of Oka–Cartan theory by L² estimates for the d-bar operator

    CERN Document Server

    Ohsawa, Takeo


    The purpose of this monograph is to present the current status of a rapidly developing part of several complex variables, motivated by the applicability of effective results to algebraic geometry and differential geometry. Highlighted are the new precise results on the L² extension of holomorphic functions. In Chapter 1, the classical questions of several complex variables motivating the development of this field are reviewed after necessary preparations from the basic notions of those variables and of complex manifolds such as holomorphic functions, pseudoconvexity, differential forms, and cohomology. In Chapter 2, the L² method of solving the d-bar equation is presented emphasizing its differential geometric aspect. In Chapter 3, a refinement of the Oka–Cartan theory is given by this method. The L² extension theorem with an optimal constant is included, obtained recently by Z. Błocki and by Q.-A. Guan and X.-Y. Zhou separately. In Chapter 4, various results on the Bergman kernel are presented, includi...

  20. Complexation-Induced Phase Separation: Preparation of Metal-Rich Polymeric Membranes

    KAUST Repository

    Villalobos Vazquez de la Parra, Luis Francisco


    The majority of state-of-the-art polymeric membranes for industrial or medical applications are fabricated by phase inversion. Complexation induced phase separation (CIPS)—a surprising variation of this well-known process—allows direct fabrication of hybrid membranes in existing facilities. In the CIPS process, a first step forms the thin metal-rich selective layer of the membrane, and a succeeding step the porous support. Precipitation of the selective layer takes place in the same solvent used to dissolve the polymer and is induced by a small concentration of metal ions. These ions form metal-coordination-based crosslinks leading to the formation of a solid skin floating on top of the liquid polymer film. A subsequent precipitation in a nonsolvent bath leads to the formation of the porous support structure. Forming the dense layer and porous support by different mechanisms while maintaining the simplicity of a phase inversion process, results in unprecedented control over the final structure of the membrane. The thickness and morphology of the dense layer as well as the porosity of the support can be controlled over a wide range by manipulating simple process parameters. CIPS facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. The nature of the CIPS process facilitates a precise loading of a high concentration of metal ions that are located in only the top layer of the membrane. Moreover, these metal ions can be converted—during the membrane fabrication process—to nanoparticles or crystals. This simple method opens up fascinating possibilities for the fabrication of metal-rich polymeric membranes with a new set of properties. This dissertation describes the process in depth and explores promising

  1. Angles in Complex Vector Spaces


    Scharnhorst, K.


    The article reviews some of the (fairly scattered) information available in the mathematical literature on the subject of angles in complex vector spaces. The following angles and their relations are considered: Euclidean, complex, and Hermitian angles, (Kasner's) pseudo-angle, the Kaehler angle (synonyms for the latter used in the literature are: angle of inclination, characteristic deviation, holomorphic deviation, holomorphy angle, Wirtinger angle, slant angle).

  2. Separation of petroleum residues by complex-formation with TiCl/sub 4/

    Energy Technology Data Exchange (ETDEWEB)

    Khokhlova, G.P.; Plyusnin, A.N.


    Titanium tetrachloride can be used for the quantitative separation of asphaltenes from residual oil products, for the concentration of hetero-atomic compounds of lower molecular weight, for the complete separation of nitrogen compounds of basic character and also for fractionation of resin-asphaltene substances. The action of TiCl/sub 4/ on residual oil products liberates asphaltenes as well as basic nitrogen compounds. The asphaltene recovery reaches 100%, and basic nitrogen compounds, 90-98%. Hexane is a more satisfactory solvent then benzene in this process.

  3. Plutonium(IV) complexation by diglycolamide ligands - coordination chemistry insight into TODGA-based actinide separations

    NARCIS (Netherlands)

    Reilly, S.D.; Gaunt, A.J.; Scott, B.L.; Modolo, G.; Iqbal, M.; Verboom, Willem; Sarsfield, M.J.


    Complexation of Pu(IV) with TMDGA, TEDGA, and TODGA diglycolamide ligands was followed by vis-NIR spectroscopy. A crystal structure determination reveals that TMDGA forms a 1:3 homoleptic Pu(IV) complex with the nitrate anions forced into the outer coordination sphere

  4. Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate. [1,2-propanediol

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Tina Kuo Fung.


    The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25{degree}C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB{sup {minus}}, with all complexes containing only one NPB{sup {minus}} per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation with B(OH){sub 4}{sup {minus}} (aq.), i.e. the complexation constants increase with increasing number of {minus}OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB{sup {minus}}) at higher concentrations. The {minus}OH group on the NPB{sup {minus}} which is left uncomplexed after one solute molecule had bound to the other two {minus}OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA{sup +} can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB{sup {minus}}. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.

  5. Separation of Strontium from Calcium by Ion-Exchange in the Presence of Complex III - USSR . (United States)


    height of_the cationite was 100 mm. In order to convert" the resin into tbe BEL-form an ammoniacal solution of 0.02 M M)TA at a pH of 10 was run...exists the danger of the elution of strontium. ÄW,ÖTV, Studies were carried out in a series of experi~_ ments on the separation of calcium and

  6. Filtration device for rapid separation of biological particles from complex matrices

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sangil; Naraghi-Arani, Pejman; Liou, Megan


    Methods and systems for filtering of biological particles are disclosed. Filtering membranes separate adjacent chambers. Through osmotic or electrokinetic processes, flow of particles is carried out through the filtering membranes. Cells, viruses and cell waste can be filtered depending on the size of the pores of the membrane. A polymer brush can be applied to a surface of the membrane to enhance filtering and prevent fouling.

  7. Type XVII collagen (BP180) and LAD-1 are present as separate trimeric complexes

    NARCIS (Netherlands)

    Pas, HH; Kloosterhuis, GJ; Nijenhuis, Albertine; de Jong, MCJM; van der Meer, JB; Jonkman, MF

    This study characterized the high molecular mass BP180 complex that is observed when unheated sodium dodecyl sulfate extracts of human skin or keratinocytes are subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. In heated extracts BP180 is present as a monomer

  8. Facile fabrication of hydrophilic nanofibrous membranes with an immobilized metal-chelate affinity complex for selective protein separation. (United States)

    Zhu, Jing; Sun, Gang


    In this study, we report a facile approach to fabricate functionalized poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofibrous membranes as immobilized metal affinity membranes for selective protein separation. Hydrophilic PVA-co-PE nanofibrous membranes with controlled fiber sizes were prepared via a melt extrusion process. A chelating group, iminodiacetic acid (IDA), was covalently attached to cyanuric acid activated membrane surfaces to form coordinative complexes with metal ions. The prepared membranes were applied to recover a model protein, lysozyme, under various conditions, and a high lysozyme adsorption capacity of 199 mg/g membrane was found under the defined optimum conditions. Smaller fiber size with a higher immobilized metal ion density on membrane surfaces showed greater lysozyme adsorption capacity. The lysozyme adsorption capacity remained consistent during five repeated cycles of adsorption-elution operations, and up to 95% of adsorbed lysozyme was efficiently eluted by using a phosphate buffer containing 0.5 M NaCl and 0.5 M imidazole as an elution media. The successful separation of lysozyme with high purity from fresh chicken egg white was achieved by using the present affinity membrane. These remarkable features, such as high capacity and selectivity, easy regeneration, as well as reliable reusability, demonstrated the great potential of the metal-chelate affinity complex immobilized nanofibrous membranes for selective protein separation.

  9. Facilitated assembly of the preinitiation complex by separated tail and head/middle modules of the mediator. (United States)

    Galdieri, Luciano; Desai, Parima; Vancura, Ales


    Mediator is a general coactivator of RNA polymerase II (RNA pol II) bridging enhancer-bound transcriptional factors with RNA pol II. Mediator is organized in three distinct subcomplexes: head, middle, and tail modules. The head and middle modules interact with RNA pol II, and the tail module interacts with transcriptional activators. Deletion of one of the tail subunits SIN4 results in derepression of a subset of genes, including FLR1, by a largely unknown mechanism. Here we show that derepression of FLR1 transcription in sin4Δ cells occurs by enhanced recruitment of the mediator as well as Swi/Snf and SAGA complexes. The tail and head/middle modules of the mediator behave as separate complexes at the induced FLR1 promoter. While the tail module remains anchored to the promoter, the head/middle modules are also found in the coding region. The separation of the tail and head/middle modules in sin4Δ cells is also supported by the altered stoichiometry of the tail and head/middle modules at several tested promoters. Deletion of another subunit of the tail module MED2 in sin4Δ cells results in significantly decreased transcription of FLR1, pointing to the importance of the integrity of the separated tail module in derepression. All tested genes exhibited increased recruitment of the tail domain; however, only genes with increased occupancy of the head/middle modules also displayed increased transcription. The separated tail module thus represents a promiscuous transcriptional factor that binds to many different promoters and is necessary for derepression of FLR1 in sin4Δ cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Korean Conference on Several Complex Variables

    CERN Document Server

    Byun, Jisoo; Gaussier, Hervé; Hirachi, Kengo; Kim, Kang-Tae; Shcherbina, Nikolay


    This volume includes 28 chapters by authors who are leading researchers of the world describing many of the up-to-date aspects in the field of several complex variables (SCV). These contributions are based upon their presentations at the 10th Korean Conference on Several Complex Variables (KSCV10), held as a satellite conference to the International Congress of Mathematicians (ICM) 2014 in Seoul, Korea. SCV has been the term for multidimensional complex analysis, one of the central research areas in mathematics. Studies over time have revealed a variety of rich, intriguing, new knowledge in complex analysis and geometry of analytic spaces and holomorphic functions which were "hidden" in the case of complex dimension one. These new theories have significant intersections with algebraic geometry, differential geometry, partial differential equations, dynamics, functional analysis and operator theory, and sheaves and cohomology, as well as the traditional analysis of holomorphic functions in all dimensions. This...

  11. Invited commentary: residential segregation and health--the complexity of modeling separate social contexts. (United States)

    Acevedo-Garcia, Dolores; Osypuk, Theresa L


    When researching racial disparities in health, residential segregation cannot be ignored. Because of segregation, contextual differences by race are so pronounced that ignoring them may lead to mis-estimating the effect of individual-level factors. However, given the stark racial separation of social contexts, researching how residential segregation and neighborhood inequality contribute to racial health disparities remains methodologically challenging. Estimating the contribution of neighborhood effects to health disparities would require overlap in the racial distributions of neighborhood environment, for example, in the distributions of neighborhood poverty. Because of segregation, though, the extent of such overlap is extremely restricted. Previous analyses of the 2000 US Census found, on average, only a 24% overlap between the distribution of neighborhood poverty for black children and that for white children in metropolitan areas. Propensity score methods may be 1 useful tool for addressing limited overlap or exchangeability. However, as shown by their application to the segregation and health relation, their use should be informed by a sound conceptualization of the scale of the social exposure of interest, the hypothesized pathways between the exposure and the health outcome, and possible unmeasured confounders.

  12. Light-harvesting complex 1 stabilizes P+QB- charge separation in reaction centers of Rhodobacter sphaeroides. (United States)

    Francia, Francesco; Dezi, Manuela; Rebecchi, Alberto; Mallardi, Antonia; Palazzo, Gerardo; Melandri, Bruno Andrea; Venturoli, Giovanni


    The kinetics of charge recombination following photoexcitation by a laser pulse have been analyzed in the reaction center-light harvesting complex 1 (RC-LH1) purified from the photosynthetic bacterium Rhodobacter sphaeroides. In RC-LH1 core complexes isolated from photosynthetically grown cells P(+)Q(B)(-) recombines with an average rate constant, k approximately 0.3 s(-1), more than three times smaller than that measured in RC deprived of the LH1 (k approximately 1 s(-1)). A comparable, slowed recombination kinetics is observed in RC-LH1 complexes purified from a pufX-deleted strain. Slowing of the charge recombination kinetics is even more pronounced in RC-LH1 complexes isolated from wild-type semiaerobically grown cells (k approximately 0.2 s(-1)). Since the kinetics of P(+)Q(A)(-) recombination is unaffected by the presence of the antenna, the P(+)Q(B)(-) state appears to be energetically stabilized in core complexes. Determinations of the ubiquinone-10 (UQ(10)) complement associated with the purified RC-LH1 complexes always yield UQ(10)/RC ratios larger than 10. These quinone molecules are functionally coupled to the RC-LH1 complex, as judged from the extent of exogenous cytochrome c(2) rapidly oxidized under continuous light excitation. Analysis of P(+)Q(B)(-) recombination, based on a kinetic model which considers fast quinone equilibrium at the Q(B) binding site, indicates that the slowing down of charge recombination kinetics observed in RC-LH1 complexes cannot be explained solely by a quinone concentration effect and suggests that stabilization of the light-induced charge separation is predominantly due to interaction of the Q(B) site with the LH1 complex. The high UQ(10) complements detected in RC-LH1 core complexes, but not in purified light-harvesting complex 2 and in RC, are proposed to reflect an in vivo heterogeneity in the distribution of the quinone pool within the chromatophore bilayer.

  13. Separation and preconcentration of copper in environmental samples on Amberlite XAD-8 resin after complexation with a carbothioamide derivative

    Directory of Open Access Journals (Sweden)

    Hamide Elvan


    Full Text Available A new solid phase extraction (SPE method has been developed for the selective separation and preconcentration of Cu (II ions in food and water samples prior to its flame atomic absorption spectrometry determination. The method is based on the adsorption of the Cu(II - 2-{[4-Amino-3-(4-methylphenyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl]acetyl}-N-phenyl hydrazinecarbothioamide complex on Amberlite XAD-8 resin. The metal complex retained on the resin was eluted with 7.5 mL of 2.0 mol L-1 HCl in acetone. The optimum conditions for the SPE of Cu(II ions were investigated, and the method was subsequently applied to sea water, stream water, rice, tea, and tobacco samples for the determination of Cu(II levels.

  14. Separation of proteins from complex bio-matrix samples using a double-functionalized polymer monolithic column. (United States)

    Zhang, Doudou; Lan, Dandan; Pang, Xiaomin; Cui, Beijiao; Bai, Ligai; Liu, Haiyan; Yan, Hongyuan


    A double-functionalized polymer monolithic column was fabricated within the confines of a stainless-steel column (50 mm × 4.6 mm i.d.) via a facile method using iron porphyrin, ionic liquid (1-allyl-3-methylimidazolium chloride) and 1,10-decanediol dimethacrylate as tri-monomers; ethylene dimethacrylate as a crosslinker; polyethylene glycol 400 and N,N-dimethylformamide as co-porogens; benzoyl peroxide and N,N-dimethyl aniline as the redox initiation system. Results obtained from scanning electron microscopy, nitrogen adsorption-desorption, and mercury intrusion porosimetry confirmed the uniform pore structure and the pore size distribution of macro-pores. The home-made monolith was further characterized by elemental analysis to investigate the elemental composition of Fe supplied by iron porphyrin, confirming the synthetic process. The resulting optimized monolithic column was used as the stationary phase in high performance liquid chromatography for separating proteins, such as mixture of standard proteins, egg white, and human plasma, exhibiting good selectivity and high performance. It is worth noting that the home-made double-functionalized polymer monolithic column shows excellent selectivity for fractionation separation of human plasma proteins, and it is a promising separation tool for complex bio-samples in proteomic research.

  15. Complexes of Magnetic Nanoparticles with Cellulose Nanocrystals as Regenerable, Highly Efficient, and Selective Platform for Protein Separation. (United States)

    Guo, Jiaqi; Filpponen, Ilari; Johansson, Leena-Sisko; Mohammadi, Pezhman; Latikka, Mika; Linder, Markus B; Ras, Robin H A; Rojas, Orlando J


    We present an efficient approach to develop cellulose nanocrystal (CNC) hybrids with magnetically responsive Fe3O4 nanoparticles that were synthesized using the (Fe(3+)/Fe(2+)) coprecipitation. After 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-catalyzed oxidation of CNC, carbodiimide (EDC/NHS) was used for coupling amine-containing iron oxide nanoparticles that were achieved by dopamine ligand exchange (NH2-Fe3O4 NPs). The as-prepared hybrids (Fe3O4@CNC) were further complexed with Cu(II) ions to produce specific protein binding sites. The performance of magnetically responsive Cu-Fe3O4@CNC hybrids was assessed by selectively separating lysozyme from aqueous media. The hybrid system displayed a remarkable binding capacity with lysozyme of 860.6 ± 14.6 mg/g while near full protein recovery (∼98%) was achieved by simple elution. Moreover, the regeneration of Fe3O4@CNC hybrids and efficient reutilization for protein separation was demonstrated. Finally, lysozyme separation from matrices containing egg white was achieved, thus revealing the specificity and potential of the presented method.

  16. Transition Metal Polypyridine Complexes: Studies of Mediation in Dye-Sensitized Solar Cells and Charge Separation

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, C. Michael [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry; Prieto, Amy L. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry


    The Elliott group has long been supported by DOE for studies of cobalt(II/III) trisbypiridine (DTB) mediator complexes in dye sensitized solar cells. Previous work demonstrated that Co(II/III) chemistry is sensitive to the environment, showing unprecedented electrode-surface and electrolyte dependant voltammetry. In electrolytes that have large lipophilic cations, voltammetry of the [Co(DTB)3]2+/3+ couple is nearly Nernstian in appearance on nominally oxide-free metal surfaces. In contrast, on semiconductor electrodes in electrolytes with small, hard cations such as Li+, the electron transfer rates are so slow that it is difficult to measure any Faradaic current even at overpotentials of ±1 V. These studies are of direct relevance to the operation of cobalt-based mediators in solar cells. The research has also shown that these mediators are compatible with copper phenantroline based dyes, in contrast to I- due to the insolubility of CuI.

  17. Calixarene receptors in the selective separation of alachlor. Characterization of the separated complexes; Receptores calixarenicos en la separacion selectiva de alaclor. Caracterizacion de los complejos separados

    Energy Technology Data Exchange (ETDEWEB)

    Garcia G, M.C


    Pesticides have been necessary in the agriculture since the plagues control have been remedied thanks to them but it has also provoked pollution. Nowadays, there are several methods which help to decrease or remedy such a pollution provoked. Unfortunately, any of them work out the environmental problem totally. Therefore, alternatives have to be found. The organic and tri dimensional characteristics of these macrocycles afford them a high versatility in such a way that these hosts can interact with organic guests selectively. Alachlor is a chlorinated organic herbicide useful in the plagues control of annual grasses and many broad-leave weeds which grow in maize, peanuts and soyabean. The ability of calixarenes to host organic guests with chemical characteristics similar to pesticides let them to be good candidates to compete with others methods which are used presently to separate organic pesticides. In this direction one of the advantages of proposing the use of calixarenes is, its facility of being modified in the lower and/or upper rims, to adapt them to aqueous, organic, gaseous and aqueous-organic media. Once the characteristics of reagents informed in the literature were confirmed and complemented with others found in this work, we studied, in solution, the interaction of the calixarenes with alachlor using 1 x 10{sup -5} to 1 x 10{sup -3} M solutions in acetonitrile for calixarenes fitted with phosphinoyl pendant arms in the lower rim, B{sub n}bL{sup n}, n= 4, 6) and in chloroform for parents calixarenes (H{sub n}bL{sup n} n = 4, 6, 8). Meticulous studies monitored by UV-Vis and luminescence were carried out, and the best stoichiometry to be used in further studies resulted to be 1(host): 1(alachlor). Therefore, we chose the 1 x 10{sup -4} M concentration to find how long the host-guest should be interacting in order to guarantee the formation in solution of the calixarene-alachlor species. It was found 168 h for the alachlor-B{sub n}bL{sup n} interaction

  18. Separation of polythionates and the gold thiosulfate complex in gold thiosulfate leach solutions by ion-interaction chromatography. (United States)

    O'Reilly, John W; Shaw, Matthew J; Dicinoski, Greg W; Grosse, Andrew C; Miura, Yasuyuki; Haddad, Paul R


    A method for the separation of the polythionates (SxO6(2-), x = 3-5) in gold thiosulfate leach solutions using ion-interaction chromatography with conductivity and ultraviolet (UV) detection is described. Polythionates were eluted within 18 min using an eluent comprising an acetonitrile step gradient at 0.0 min from 15% v/v to 28% v/v, 3 mM TBAOH, and 2.5 mM sodium carbonate, operated using a Dionex NS1-5 micron column with guard. The developed method was capable of separating the gold thiosulfate complex ion in standard solutions, but quantification of this species in realistic leach solutions proved impractical due to a self-elution effect that caused the gold peak to be eluted as a broad band. Detection limits for polythionates using a 10 microL injection volume ranged between 1-6 mg L(-1) (5-23 microM) for conductivity and 0.8-13 mg L(-1) (4-68 microM) for UV detection, based on a signal-to-noise ratio of 2. Calibration was linear over the ranges 5-2000, 10-2000 and 25-2500 mg L(-1) for trithionate, tetrathionate and pentathionate, respectively. The technique was applied successfully to leach liquors containing 0.5 M ammonium thiosulfate, 2 M ammonia, 0.05 M copper sulfate and 20 % m/v gold ore.

  19. Gradient elution method in centrifugal partition chromatography for the separation of a complex sophorolipid mixture obtained from Candida bombicola yeasts. (United States)

    Kotland, Alexis; Hadef, Imane; Renault, Jean-Hugues; Hamzaoui, Mahmoud; Martinez, Agathe; Borie, Nicolas; Guilleret, Arnaud; Reynaud, Romain; Hubert, Jane


    Sophorolipids represent an important class of natural surfactants with a variety of environmental, cosmetic, and pharmaceutical applications. Despite their promising physicochemical and biological properties, the use of sophorolipids is hampered by the lack of information regarding their individual structure-activity relationships. The major difficulty in isolating pure sophorolipids arises from the high complexity of crude fermentation media composition and from their strong structural similarities. In this work, a centrifugal partition chromatography method was developed in an original gradient elution mode for the separation of sophorolipids produced by the yeast Candida bombicola. Experiments were realized by using three sets of solvent systems composed of n-heptane, ethyl acetate, n-butanol, methanol, and water in different proportions. The separation was performed at 5 mL/min in the ascending mode by increasing progressively the polarity of the organic mobile phase. In these conditions, more than 80% of the sophorolipids present in the initial crude fermentation extract were eluted successively from the most hydrophobic lactone forms to the most hydrophilic acid forms. The structures of the isolated sophorolipids were further elucidated by HPLC and NMR analyses. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Complex differential geometry

    CERN Document Server

    Zheng, Fangyang


    The theory of complex manifolds overlaps with several branches of mathematics, including differential geometry, algebraic geometry, several complex variables, global analysis, topology, algebraic number theory, and mathematical physics. Complex manifolds provide a rich class of geometric objects, for example the (common) zero locus of any generic set of complex polynomials is always a complex manifold. Yet complex manifolds behave differently than generic smooth manifolds; they are more coherent and fragile. The rich yet restrictive character of complex manifolds makes them a special and interesting object of study. This book is a self-contained graduate textbook that discusses the differential geometric aspects of complex manifolds. The first part contains standard materials from general topology, differentiable manifolds, and basic Riemannian geometry. The second part discusses complex manifolds and analytic varieties, sheaves and holomorphic vector bundles, and gives a brief account of the surface classifi...

  1. A classical Perron method for existence of smooth solutions to boundary value and obstacle problems for degenerate-elliptic operators via holomorphic maps (United States)

    Feehan, Paul M. N.


    We prove existence of solutions to boundary value problems and obstacle problems for degenerate-elliptic, linear, second-order partial differential operators with partial Dirichlet boundary conditions using a new version of the Perron method. The elliptic operators considered have a degeneracy along a portion of the domain boundary which is similar to the degeneracy of a model linear operator identified by Daskalopoulos and Hamilton [9] in their study of the porous medium equation or the degeneracy of the Heston operator [21] in mathematical finance. Existence of a solution to the partial Dirichlet problem on a half-ball, where the operator becomes degenerate on the flat boundary and a Dirichlet condition is only imposed on the spherical boundary, provides the key additional ingredient required for our Perron method. Surprisingly, proving existence of a solution to this partial Dirichlet problem with ;mixed; boundary conditions on a half-ball is more challenging than one might expect. Due to the difficulty in developing a global Schauder estimate and due to compatibility conditions arising where the ;degenerate; and ;non-degenerate boundaries; touch, one cannot directly apply the continuity or approximate solution methods. However, in dimension two, there is a holomorphic map from the half-disk onto the infinite strip in the complex plane and one can extend this definition to higher dimensions to give a diffeomorphism from the half-ball onto the infinite ;slab;. The solution to the partial Dirichlet problem on the half-ball can thus be converted to a partial Dirichlet problem on the slab, albeit for an operator which now has exponentially growing coefficients. The required Schauder regularity theory and existence of a solution to the partial Dirichlet problem on the slab can nevertheless be obtained using previous work of the author and C. Pop [16]. Our Perron method relies on weak and strong maximum principles for degenerate-elliptic operators, concepts of

  2. Near-Infrared Photoelectrochemical Conversion via Photoinduced Charge Separation in Supramolecular Complexes of Anionic Phthalocyanines with Li(+)@C60. (United States)

    Kawashima, Yuki; Ohkubo, Kei; Blas-Ferrando, Vicente Manuel; Sakai, Hayato; Font-Sanchis, Enrique; Ortíz, Javier; Fernández-Lázaro, Fernando; Hasobe, Taku; Sastre-Santos, Ángela; Fukuzumi, Shunichi


    Two phthalocyanines possessing carboxylate groups ((TBA)4H2Pc·1 and (TBA)4H2Pc·2) form 1:2 supramolecular complexes with lithium cation-encapsulated C60 (Li(+)@C60) [H2Pc·1(4-)/(Li(+)@C60)2 and H2Pc·2(4-)/(Li(+)@C60)2] in a polar mixed solvent. From the UV-vis spectral changes, the binding constants (K) were estimated as ca. 10(12) M(-2). Upon the photoexcitation of constructed supramolecular complexes, photoinduced electron transfer occurred to form the charge-separated (CS) state. The lifetime of the CS state was determined to be 1.2 ms for H2Pc·2(4-)/(Li(+)@C60)2, which is the longest CS lifetime among the porphyrinoid/fullerene supramolecular complexes. H2Pc·1(4-)/(Li(+)@C60)2 also afforded the long-lived CS state of 1.0 ms. The spin state of the long-lived CS states was determined to be a triplet, as indicated by the EPR signal at g = 4. The reorganization energy (λ) and the electronic coupling term were determined to be λ = 1.70 eV, V = 0.15 cm(-1) from the temperature dependence of the rate constant for the charge recombination of the CS state of H2Pc·1(4-)/(Li(+)@C60)2. The energy of the CS state (0.49 eV) is much smaller than the reorganization energy, indicating that the back-electron-transfer process is located in the Marcus normal region. The small electronic coupling term results from the spin-forbidden back electron transfer due to the triplet CS state. Supramolecular complexes of anionic zinc phthalocyanines with Li(+)@C60 were also prepared and investigated. The ZnPc·4(4-)/Li(+)@C60 supramolecular nanoclusters were assembled on the optically transparent electrode (OTE) of nanostructured SnO2 (OTE/SnO2) to construct the dye-sensitized solar cell. The IPCE (incident photon-to-photocurrent efficiency) values of OTE/SnO2/(ZnPc·4(4-)/Li(+)@C60)n were much higher than the sum of the two IPCE values of the individual systems OTE/SnO2/(Li(+)@C60)n and OTE/SnO2/(ZnPc·4(4-))n, covering the near-infrared region.

  3. Separation system suitability (3S): a new criterion of chromatogram classification in HPLC based on cross-evaluation of separation capacity/peak symmetry and its application to complex mixtures of anthraquinones. (United States)

    Nowik, Witold; Héron, Sylvie; Bonose, Myriam; Tchapla, Alain


    A comparison of chromatograms obtained in a series of separation conditions for a given complex mixture may be done with a series of chromatographic descriptors. In this study, we used two descriptors: the number of critical pairs and symmetry of peaks, further rescaled and converted to the corresponding critical pairs' coefficient (CPc) and symmetry coefficient (Sc). Considering the difficulty of appreciating global separation quality using CPc and Sc criteria separately, as their respective values are usually uncorrelated, a double-criteria cross-evaluation system was required. For that purpose we tested the commonly used multi-criteria decision-making method - Derringer's desirability function (D) - as well as the recently introduced sum of ranking differences (SRD). To facilitate the graphical comparison of both approaches, the desirability function (D) was used in the inverse form (Dinv). The advantages and drawbacks of both evaluation methods, especially the respective under- or over-evaluation of outliers, caused us to introduce a new ranking approach, separation system suitability (3S). The obtained suitability rankings for the three tested approaches (Dinv, SRD and 3S) are different; nevertheless, 3S appears to be the most balanced and the easiest to interpret as well. The approach developed for selection of suitable systems was applied to the problem of separation of complex mixtures through the analysis of a series of standards of anthraquinone derivatives. To judge the pertinence of this evaluation, a sample containing a number of natural anthraquinones extracted from the bark of Indian mulberry (Morinda citrifolia) was analysed. In conclusion, the proposed methodology for the cross-evaluation of the series of chromatograms using single specific descriptors (CPc and Sc) through a global composite descriptor (3S) significantly simplifies the decision that separation systems are the most suitable for the separation of complex target mixtures of compounds.

  4. Complex ventral hernia repair using components separation with or without biologic mesh: a cost-utility analysis. (United States)

    Chatterjee, Abhishek; Krishnan, Naveen M; Rosen, Joseph M


    A complex ventral hernia requiring abdominal wall reconstruction presents a challenging scenario to the surgeon. The use of biologic mesh in addition to performing a components separation (CS) is controversial. Our goal was to perform the first cost-utility analysis on the use of biologic mesh in addition to performing CS when performing complex ventral hernia repair. A comprehensive literature review was conducted to identify published complication and recurrence rates for ventral hernia repairs requiring CS with or without biologic mesh. The probabilities of the most common complications were combined with Medicare Current Procedural Terminology reimbursement codes, diagnosis related group reimbursement codes, and expert utility estimates to fit into a decision model to evaluate the cost utility of CS with and without biologic mesh in reconstructing ventral hernias. The decision model revealed a baseline cost increase of $775.65 and a 0.0517 increase in the quality-adjusted life-years when using biologic mesh yielding an incremental cost-utility ratio of $15,002.90/quality-adjusted life-year. One-way sensitivity analysis revealed that using biologic mesh was cost-effective using Medicare reimbursement rates but not at retail costs. The maximum price of biologic mesh to be cost-effective was $1813.53. The cost utility of biologic mesh when used with CS in ventral hernia repair is dependent on the financial perspective. It is cost-ineffective for hospitals and physicians paying retail costs but cost-effective for third-party payers providing Medicare reimbursement.

  5. Complexation induced phase separation: preparation of composite membranes with a nanometer thin dense skin loaded with metal ions

    KAUST Repository

    Villalobos Vazquez de la Parra, Luis Francisco


    We present the development of a facile phase-inversion method for forming asymmetric membranes with a precise high metal ion loading capacity in only the dense layer. The approach combines the use of macromolecule-metal intermolecular complexes to form the dense layer of asymmetric membranes with nonsolvent-induced phase separation to form the porous support. This allows the independent optimization of both the dense layer and porous support while maintaining the simplicity of a phase-inversion process. Moreover, it facilitates control over (i) the thickness of the dense layer throughout several orders of magnitude—from less than 15 nm to more than 6 μm, (ii) the type and amount of metal ions loaded in the dense layer, (iii) the morphology of the membrane surface, and (iv) the porosity and structure of the support. This simple and scalable process provides a new platform for building multifunctional membranes with a high loading of well-dispersed metal ions in the dense layer.

  6. Charge separation in donor-C60 complexes with real-time Green's functions: The importance of nonlocal correlations. (United States)

    Bostrom, Emil Vinas; Mikkelsen, Anders; Verdozzi, Claudio; Perfetto, Enrico; Stefanucci, Gianluca


    We use the Nonequilibrium Green's Function (NEGF) method to perform real-time simulations of the ultrafast electron dynamics of photoexcited donor-C60 complexes modeled by a Pariser-Parr-Pople Hamiltonian. The NEGF results are compared to mean-field Hartree-Fock (HF) calculations to disentangle the role of correlations. Initial benchmarking against numerically highly accurate time dependent Density Matrix Renormalization Group calculations verifies the accuracy of NEGF. We then find that charge-transfer (CT) excitons partially decay into charge separated (CS) states if dynamical non-local correlation corrections are included. This CS process occurs in ∼10 fs after photoexcitation. In contrast, the probability of exciton recombination is almost 100% in HF simulations. These results are largely unaffected by nuclear vibrations; the latter become however essential whenever level misalignment hinders the CT process. The robust nature of our findings indicate that ultrafast CS driven by correlation-induced decoherence may occur in many organic nanoscale systems, but it will only be correctly predicted by theoretical treatments that include time-nonlocal correlations.

  7. Ambiguity in the Manifestation of Adult Separation Anxiety Disorder Occurring in Complex Anxiety Presentations: Two Clinical Case Reports (United States)

    Dudaee-Faass, Sigal; Marnane, Claire; Wagner, Renate


    Two case reports are described in which patients presented for the treatment of multiple comorbid anxiety disorders, all of which appeared to derive from prolonged separation anxiety disorder. In particular, these adults had effectively altered their lifestyles to avoid separation, thereby displaying only ambiguous separation anxiety symptoms that…

  8. Selectivity of bis-triazinyl bipyridine ligands for americium(III) in Am/Eu separation by solvent extraction. Part 1. Quantum mechanical study on the structures of BTBP complexes and on the energy of the separation. (United States)

    Narbutt, Jerzy; Oziminski, Wojciech P


    Theoretical studies were carried out on two pairs of americium and europium complexes formed by tetra-N-dentate lipophilic BTBP ligands, neutral [ML(NO(3))(3)] and cationic [ML(2)](3+) where M = Am(III) or Eu(III), and L = 6,6'-bis-(5,6-diethyl-1,2,4-triazin-3-yl)-2,2'-bipyridine (C2-BTBP). Molecular structures of the complexes have been optimized at the B3LYP/6-31G(d) level and total energies of the complexes in various media were estimated using single point calculations performed at the B3LYP/6-311G(d,p) and MP2/6-311G(d,p) levels of theory. In the calculations americium and europium ions were treated using pseudo-relativistic Stuttgart-Dresden effective core potentials and the accompanying basis sets. Selectivity in solvent extraction separation of two metal ions is a co-operative function of contributions from all extractable metal complexes, which depend on physico-chemical properties of each individual complex and on its relative amount in the system. Semi-quantitative analysis of BTBP selectivity in the Am/Eu separation process, based on the contributions from the two pairs of Am(III) and Eu(III) complexes, has been carried out. To calculate the energy of Am/Eu separation, a model of the extraction process was used, consisting of complex formation in water and transfer of the formed complex to the organic phase. Under the assumptions discussed in the paper, this simple two-step model results in reliable values of the calculated differences in the energy changes for each pair of the Am/Eu complexes in both steps of the process. The greater thermodynamic stability (in water) of the Am-BTBP complexes, as compared with the analogous Eu species, caused by greater covalency of the Am-N than Eu-N bonds, is most likely the main reason for BTBP selectivity in the separation of the two metal ions. The other potential reason, i.e. differences in lipophilic properties of the analogous complexes of Am and Eu, is less important with regard to this selectivity.

  9. On the asymptotic behavior of complex earthquakes and Teichmüller disks

    DEFF Research Database (Denmark)

    Gupta, Subhojoy


    Given a hyperbolic surface and a simple closed geodesic on it, complex-twists along the curve produce a holomorphic family of deformations in Teichmuller space, degenerating to the Riemann surface where it is pinched. We show there is a corresponding Teichmuller disk such that the two are strongl...

  10. Elementary theory of analytic functions of one or several complex variables

    CERN Document Server

    Cartan, Henri


    Noted mathematician offers basic treatment of theory of analytic functions of a complex variable, touching on analytic functions of several real or complex variables as well as the existence theorem for solutions of differential systems where data is analytic. Also included is a systematic, though elementary, exposition of theory of abstract complex manifolds of one complex dimension. Topics include power series in one variable, holomorphic functions, Cauchy's integral, more. Exercises. 1973 edition.

  11. Synthesis, Crystal Structure, Gas Absorption, and Separation Properties of a Novel Complex Based on Pr and a Three-Connected Ligand

    Directory of Open Access Journals (Sweden)

    Jie Sun


    Full Text Available A novel Pr complex, constructed from a rigid three-connected H3TMTA and praseodymium(III ion, has been synthesized in a mixed solvent system and characterized by X-ray single crystal diffraction, infrared spectroscopy, a thermogravimetric analysis, an element analysis, and powder X-ray diffraction, which reveals that complex 1 crystallizes in a three-dimensional porous framework. Moreover, the thermal stabilities and the fluorescent and gas adsorption and separation properties of complex 1 were investigated systematically.

  12. Extraction separation of rare-earth ions via competitive ligand complexations between aqueous and ionic-liquid phases. (United States)

    Sun, Xiaoqi; Bell, Jason R; Luo, Huimin; Dai, Sheng


    The extraction separation of rare earth elements is one of the most challenging separation processes in hydrometallurgy and advanced nuclear fuel cycles. The TALSPEAK process (trivalent actinide lanthanide separations by phosphorus-reagent extraction from aqueous komplexes) is a prime example of these separation processes. The objective of this paper is to explore the use of ionic liquids (ILs) for the TALSPEAK-like process, to further enhance its extraction efficiencies for lanthanides, and to investigate the potential of using this modified TALSPEAK process for separation of lanthanides among themselves. Eight imidazolium ILs ([C(n)mim][NTf(2)] and [C(n)mim][BETI], n = 4,6,8,10) and one pyrrolidinium IL ([C(4)mPy][NTf(2)]) were investigated as diluents using di(2-ethylhexyl)phosphoric acid (HDEHP) as an extractant for the separation of lanthanide ions from aqueous solutions of 50 mM glycolic acid or citric acid and 5 mM diethylenetriamine pentaacetic acid (DTPA). The extraction efficiencies were studied in comparison with diisopropylbenzene (DIPB), an organic solvent used as a diluent for the conventional TALSPEAK extraction system. Excellent extraction efficiencies and selectivities were found for a number of lanthanide ions using HDEHP as an extractant in these ILs. The effects of different alkyl chain lengths in the cations of ILs and of different anions on extraction efficiencies and selectivities of lanthanide ions are also presented in this paper. This journal is © The Royal Society of Chemistry 2011

  13. Complexation of Actinide(III) and Lanthanide(III) with H4TPAEN for a Separation of Americium from Curium and Lanthanides. (United States)

    Boubals, Nathalie; Wagner, Christoph; Dumas, Thomas; Chanèac, Léa; Manie, Gabriel; Kaufholz, Peter; Marie, Cécile; Panak, Petra J; Modolo, Giuseppe; Geist, Andreas; Guilbaud, Philippe


    Previous studies have identified the TPAEN ligand as a potentially appropriate complexing agent in solvent extraction processes for the separation of americium (Am(III)) from the fission products including lanthanide (Ln(III)) and curium (Cm(III)) ions, a challenging issue for advanced nuclear fuel recycling. To get insight into the selectivity of this ligand, the complexation of selected trivalent Ln(III) and actinide (An(III)) cations with TPAEN was investigated in solution. First, the structure and stoichiometry of the TPAEN complex with Am(III) were characterized by extended X-ray absorption fine structure spectroscopy (EXAFS). Then complexation constants and thermodynamics data were acquired for the complexes using different methods: microcalorimetry for the Ln(III) cations, time-resolved laser fluorescence spectroscopy (TRLFS) for Eu(III) and Cm(III), and UV-visible spectroscopy for Nd(III) and Am(III).

  14. Plutonium(IV) complexation by diglycolamide ligands--coordination chemistry insight into TODGA-based actinide separations. (United States)

    Reilly, Sean D; Gaunt, Andrew J; Scott, Brian L; Modolo, Giuseppe; Iqbal, Mudassir; Verboom, Willem; Sarsfield, Mark J


    Complexation of Pu(IV) with TMDGA, TEDGA, and TODGA diglycolamide ligands was followed by vis-NIR spectroscopy. A crystal structure determination reveals that TMDGA forms a 1 : 3 homoleptic Pu(IV) complex with the nitrate anions forced into the outer coordination sphere.

  15. Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation

    DEFF Research Database (Denmark)

    Supur, M.; Kawashima, Y.; Larsen, K. R.


    Inclusion complexes of benzo-and dithiabenzocrown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C-60 (1 center dot Li+@C-60 and 2 center dot Li+@C-60). The strong complexation has been quantified by high binding constants that exceed 10(6) (-1)(M) obtai...

  16. The structures of CyMe4-BTBP complexes of americium(iii) and europium(iii) in solvents used in solvent extraction, explaining their separation properties. (United States)

    Ekberg, Christian; Löfström-Engdahl, Elin; Aneheim, Emma; Foreman, Mark R StJ; Geist, Andreas; Lundberg, Daniel; Denecke, Melissa; Persson, Ingmar


    Separation of trivalent actinoid (An(iii)) and lanthanoid (Ln(iii)) ions is extremely challenging due to their similar ionic radii and chemical properties. Poly-aromatic nitrogen compounds acting as tetradentate chelating ligands to the metal ions in the extraction, have the ability to sufficiently separate An(iii) from Ln(iii). One of these compounds, 6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzol[1,2,4]triazin-3-yl)[2,2]bipyridine, CyMe4-BTBP, has proven to be resistant towards acidic environments and strong radiation from radioactive decomposition. EXAFS studies of the dicomplexes of CyMe4-BTBP with americium(iii) and europium(iii) in nitrobenzene, cyclohexanone, 1-hexanol, 1-octanol and malonamide (DMDOHEMA) in 1-octanol have been carried out to get a deeper understanding of the parameters responsible for the separation. The predominating complexes independent of solvent used are [Am(CyMe4-BTBP)2(NO3)](2+) and [Eu(CyMe4-BTBP)2](3+), respectively, which are present as outer-sphere ion-pairs with nitrate ions in the studied solvents with low relative permittivity. The presence of a nitrate ion in the first coordination sphere of the americium(iii) complex compensates the charge density of the complex considerably in comparison when only outer-sphere ion-pairs are formed as for the [Eu(CyMe4-BTBP)2](3+) complex. The stability and solubility of a complex in a solvent with low relative permittivity increase with decreasing charge density. The [Am(CyMe4-BTBP)2(NO3)](2+) complex will therefore be increasingly soluble and stabilized over the [Eu(CyMe4-BTBP)2](3+) complex in solvents with decreasing relative permittivity of the solvent. The separation of americium(iii) from europium(iii) with CyMe4-BTBP as extraction agent will increase with decreasing relative permittivity of the solvent, and thereby also with decreasing solubility of CyMe4-BTBP. The choice of solvent is therefore a balance of a high separation factor and sufficient solubility of the CyMe4-BTBP

  17. Combinations of complex dynamical systems

    CERN Document Server

    Pilgrim, Kevin M


    This work is a research-level monograph whose goal is to develop a general combination, decomposition, and structure theory for branched coverings of the two-sphere to itself, regarded as the combinatorial and topological objects which arise in the classification of certain holomorphic dynamical systems on the Riemann sphere. It is intended for researchers interested in the classification of those complex one-dimensional dynamical systems which are in some loose sense tame. The program is motivated by the dictionary between the theories of iterated rational maps and Kleinian groups.

  18. Numerical simulation of gas flow and droplet motion in a wave-plate eliminator of the separator-steam-generator system in the waste-heat-utilisation complex (United States)

    Artemov, Valerij; Minko, Konstantin; Yankov, Georgij; Ptakhin, Anton; Kondratev, Anton; Milman, Oleg


    This paper studied the droplet transport and deposition in the turbulent flow inside a wave-plate eliminator of the waste-heat utilisation complex (WHUC). The Lagrangian discrete particle approach was used to simulate the process of liquid separation from wet steam flow. Two different models for droplet-eddy interaction were tested using data from the available literature. The tested numerical model was used to predict the WHUC performance.

  19. Towards a selective adsorbent for arsenate and selenite in the presence of phosphate: Assessment of adsorption efficiency, mechanism, and binary separation factors of the chitosan-copper complex. (United States)

    Yamani, Jamila S; Lounsbury, Amanda W; Zimmerman, Julie B


    The potential for a chitosan-copper polymer complex to select for the target contaminants in the presence of their respective competitive ions was evaluated by synthesizing chitosan-copper beads (CCB) for the treatment of (arsenate:phosphate), (selenite:phosphate), and (selenate:sulfate). Based on work by Rhazi et al., copper (II) binds to the amine moiety on the chitosan backbone as a monodentate complex (Type I) and as a bidentate complex crosslinking two polymer chains (Type II), depending on pH and copper loading. In general, the Type I complex exists alone; however, beyond threshold conditions of pH 5.5 during synthesis and a copper loading of 0.25 mol Cu(II)/mol chitosan monomer, the Type I and Type II complexes coexist. Subsequent chelation of this chitosan-copper ligand to oxyanions results in enhanced and selective adsorption of the target contaminants in complex matrices with high background ion concentrations. With differing affinities for arsenate, selenite, and phosphate, the Type I complex favors phosphate chelation while the Type II complex favors arsenate chelation due to electrostatic considerations and selenite chelation due to steric effects. No trend was exhibited for the selenate:sulfate system possibly due to the high Ksp of the corresponding copper salts. Binary separation factors, α12, were calculated for the arsenate-phosphate and selenite-phosphate systems, supporting the mechanistic hypothesis. While, further research is needed to develop a synthesis method for the independent formation of the Type II complexes to select for target contaminants in complex matrices, this work can provide initial steps in the development of a selective adsorbent. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Separate Colors, Separate Minds. (United States)

    Meyers, Michael; Nidiry, John P.


    Explains that racial separation causes cultural separation, and the way to improve race relations is to continue to move toward integration. Discusses the need to debunk race, examining racial issues in education. Highlights the importance of actively supporting integration and opposing separatism, explaining that for there to be social progress,…

  1. Comparison between pervaporation and vapor permeation for separation of water-alcohol mixtures using a polyion complex membrane; Polyion complex maku wo mochiita mizu/alcohol kongoeki bunri ni okeru shinto kikaho to joki tokaho no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, t. [Daicel Chemical Industries, Ltd., Osaka (Japan); Taya, M.; Tone, S. [Osaka University, Osaka (Japan). Faculty of Engineering Science


    A water-alcohol separation experiment based on the pervaporation (in which the membrane touches the feed solution side) and vapor permeation (in which it touches the vapor) methods of water-ethanol and water-2-propanol azeotropic mixtures was conducted using the polyion complex membrane that is a water permselective membrane. In both methods, the total permeation flux was higher in pervaporation than in vapor permeation in the range where the mole fraction of ethanol and 2-propanol in a feed solution is less than 0.9. The separation factor was higher in pervaporation than in vapor permeation in the range where the mole fraction in a feed solution is more than 0.9 in water-ethanol and more than 0.7 in water-2-propanol. The membrane separation efficiency based on a solution-diffusion theory was represented as a separation index that is the product of the total permeation flux and separation factor. The separation index was higher in pervaporation than in vapor permeation in the range where the mole fraction in a feed solution is more than 0.82 in water-ethanol and more than 0.43 in water-2-propanol. 8 refs., 3 figs., 1 tab.

  2. Stereo-complex crystallization of poly(lactic acid)s in block-copolymer phase separation. (United States)

    Uehara, Hiroki; Karaki, Yusuke; Wada, Shizuka; Yamanobe, Takeshi


    Block-copolymer containing a poly(L-lactic acid) (PLLA) segment was blended with pure poly(D-lactic acid) (PDLA) chain in chloroform solution and casted into the dried film. This method could form the stereocomplex (Sc) crystal of PLLA/PDLA within the nanometer-sized phase separation self-assembled by block-copolymer. Differential scanning calorimetry measurements of the prepared and annealed films gave the maximum achievable melting temperature of 245 °C, which was highest among those previously reported for PLA Sc-crystals. Surprisingly, all of added PDLA chains were Sc-crystallized, depending on the blend composition with block-copolymer containing PLLA.

  3. Effects of Direct Instruction Rewards Program Strategies to Teach Separation of Complex Words to Two High School Students with Disabilities (United States)

    Mullaney, Lauren; Baker, Megan; Rutherford, Katie; Neyman, Jennifer; McLaughlin, T. F.; Stookey, Susan


    The purpose of the study was to evaluate the effects of the Direct Instruction REWARDS® program on reading complex words of two fifteen-year-old boys in a reading resource room. Both participants had difficulty in reading and were diagnosed as learning disabled. During baseline, both participants had difficulty in syllabication. The results showed…

  4. Separation of heavy metal from water samples--The study of the synthesis of complex compounds of heavy metal with dithiocarbamates. (United States)

    Kane, Sonila; Lazo, Pranvera; Ylli, Fatos; Stafilov, Trajce; Qarri, Flora; Marku, Elda


    The toxicity and persistence of heavy metal (HM) ions may cause several problems to marine organisms and human beings. For this reason, it is growing the interest in the chemistry of sulphur donor ligands such as dithiocarbamates (DDTC), due to their applications particularly in analytical chemistry sciences. The aim of this work has been the study of heavy metal complexes with DDTC and their application in separation techniques for the preconcentration and/or removing of heavy metals from the water solutions or the water ecosystems prior to their analysis. The HM-DDTC complexes were prepared and characterized by elemental analysis, FTIR and UV-Vis spectroscopic methods. The elemental analysis and the yield of the synthesis (97.5-99.9%) revealed a good purity of the complexes. High values of complex formation yields of HM-DDTC complexes is an important parameter for quantitatively removing/and or preconcentration of heavy metal ions from water solution even at low concentration of heavy metals. Significant differences founded between the characteristic parameters of UV/Vis (λmax and ϵmax) and FTIR absorption spectra of the parent DDTC and HM-DDTC complexes revealed the complex formation. The presence of the peaks at the visible spectral zone is important to M(nd(10-m))-L electron charge transfer of the new complexes. The (C=N) (1450-1500 cm(-1)) and the un-splitting (C-S) band (950-1002 cm(-1)) in HM-DDTC FTIR spectra are important to the identification of their bidentate mode (HM[S2CNC4H10]2). The total CHCl3 extraction of trace level heavy metals from water samples after their complex formation with DDTC is reported in this article.

  5. Fabrication of a novel hemin-based monolithic column and its application in separation of protein from complex bio-matrix. (United States)

    Jiang, Xiaoya; Zhang, Doudou; Li, Xueying; Wang, Xixi; Bai, Ligai; Liu, Haiyan; Yan, Hongyuan


    A novel polymer-based monolithic column was prepared via redox initiation system within the confines of a stainless steel column with 4.6mm i.d. In the processes, hemin and lauryl methacrylate were used as co-monomers; ethylene dimethacrylate as crosslinking agent; n-butyl alcohol, ethanediol, and N, N-dimethylformamide as tri-porogens; benzoyl peroxide and N, N-dimethyl aniline as redox initiation system. The resulting polymer-based monolithic columns were characterized by scanning electron microscopy, nitrogen adsorption-desorption instrument, and mercury intrusion porosimeter, respectively. The results illustrated that the improved monolith had relative uniform porous structure, good permeability, and low back pressure. Aromatic compounds were used to test the chromatographic behavior of the monolith, resulting in highest column efficiency of 19 880 plates per meter with reversed-phase mechanism. Furthermore, the homemade monolith was used as the stationary phase of high performance liquid chromatography to separate proteins from complex bio-matrix, including human plasma, egg white, and snailase. The results showed that the monolithic column occupied good separation ability with these complex bio-samples. Excellent specific character of the homemade hemin-based monolith was that it could simultaneously remove high-abundance proteins (including human serum albumin, immunoglobulin G, and human fibrinogen) from human plasma and separate other proteins to different fractions. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Modified diglycol-amides for actinide separation: solvent extraction and time-resolved laser fluorescence spectroscopy complexation studies

    Energy Technology Data Exchange (ETDEWEB)

    Wilden, A.; Modolo, G.; Lange, S.; Sadowski, F.; Bosbach, D. [Foschungszentrum Juelich GmbH, IEK-6, Juelich (Germany); Beele, B.B.; Panak, P.J. [Ruprecht-Karls-Universitaet Heidelberg, Physikalisch Chemisces Institut - PCI, Heidelberg (Germany); Karlsruher Institut fuer Technologie - INE, Karlsruhe (Germany); Skerencak-Frech, A.; Geist, A. [Karlsruher Institut fuer Technologie - INE, Karlsruhe (Germany); Iqbal, M. [University of Twente, Laboratory of Molecular Nanofabrication, Enschede (Netherlands); Department of Chemistry, University of Sargodha, Sargodha 40100 (Pakistan); Verboom, W. [University of Twente, Laboratory of Molecular Nanofabrication, Enschede (Netherlands)


    In this work, the back-bone of the diglycolamide-structure of the TODGA extractant was modified by adding one or two methyl groups to the central methylene carbon-atoms. The influence of these structural modifications on the extraction behavior of trivalent actinides and lanthanides and other fission products was studied in solvent extraction experiments. The addition of methyl groups to the central methylene carbon atoms leads to reduced distribution ratios, also for Sr(II). This reduced extraction efficiency for Sr(II) is beneficial for process applications, as the co-extraction of Sr(II) can be avoided, resulting in an easier process design. The use of these modified diglycol-amides in solvent extraction processes is discussed. Furthermore, the complexation of Cm(III) and Eu(III) to the ligands was studied using Time-Resolved-Laser-Fluorescence-Spectroscopy (TRLFS). The complexes were characterized by slope analysis and conditional stability constants were determined.

  7. Enantiomeric separation of ornithine in complex mixtures of amino acids by EKC with off-line derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. (United States)

    Martínez-Girón, Ana Belén; Domínguez-Vega, Elena; García-Ruiz, Carmen; Crego, Antonio L; Marina, Maria Luisa


    A new analytical methodology was developed by EKC enabling the fast enantiomeric separation of Ornithine in complex mixtures of amino acids. A previous derivatization step with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) was achieved to enable the sensitive UV detection of amino acids as well as to make possible their interaction with the CDs employed as chiral selectors. A dual CD system containing an anionic and a neutral CD in phosphate buffer at acid pH showed a high resolving power allowing the enantiomeric separation of 18 protein amino acids and Orn. The method was applied to the analysis of fermented foods to investigate the extent of the presence of Orn enantiomers.

  8. Separation of americium by liquid-liquid extraction using diglycol-amides water-soluble complexing agents

    Energy Technology Data Exchange (ETDEWEB)

    Chapron, S.; Marie, C.; Pacary, V.; Duchesne, M.T.; Miguirditchian, M. [CEA, Centre de Marcoule, Nuclear Energy Division, RadioChemistry and Processses Departement, 30207 Bagnols-sur-Ceze (France); Arrachart, G.; Pellet-Rostaing, S. [Institut de Chimie Separative de Marcoule, LTSM, Bat 426, F-30207 Bagnols-sur- Ceze (France)


    Recycling americium (Am) alone from spent nuclear fuels is an important option studied for the future nuclear cycle (Generation IV systems) since Am belongs to the main contributors of the long-term radiotoxicity and heat power of final waste. Since 2008, a liquid-liquid extraction process called EXAm has been developed by the CEA to allow the recovery of Am alone from a PUREX raffinate (a dissolution solution already cleared from U, Np and Pu). A mixture of DMDOHEMA (N,N'-dimethyl-N,N'-dioctyl-2-(2-(hexyloxy)ethyl)-malonamide) and HDEHP (di-2-ethylhexylphosphoric acid) in TPH is used as the solvent and the Am/Cm selectivity is improved using TEDGA (N,N,N',N'-tetraethyl-diglycolamide) as a selective complexing agent to maintain Cm and heavier lanthanides in the acidic aqueous phase (5 M HNO{sub 3}). Americium is then stripped selectively from light lanthanides at low acidity (pH=3) with a poly-aminocarboxylic acid. The feasibility of sole Am recovery was already demonstrated during hot tests in ATALANTE facility and the EXAm process was adapted to a concentrated raffinate to optimize the process compactness. The speciation of TEDGA complexes formed in the aqueous phase with Am, Cm and lanthanides was studied to better understand and model the behavior of TEDGA in the process. Some Ln-TEDGA species are extracted into the organic phase and this specific chemistry might play a role in the Am/Cm selectivity improvement. Hence the hydrophilicity-lipophilicity balance of the complexing agent is an important parameter. In this comprehensive study, new analogues of TEDGA were synthesized and tested in the EXAm process conditions to understand the relationship between their structure and selectivity. New derivatives of TEDGA with different N-alkyl chain lengths and ramifications were synthesized. The impact of lipophilicity on ligand partitioning and Am/Cm selectivity was investigated. (authors)

  9. Nano-scale imaging and spectroscopy of plasmonic systems, thermal near-fields, and phase separation in complex oxides (United States)

    Jones, Andrew C.

    -rods. Strong spatial field variation on lengths scales as short as 20 nm is observed associated with the dipolar and quadrupolar modes of both systems with details sensitively depending on the nanoparticle structure and environment. In light of recent publications predicting distinct spectral characteristics of thermal electromagnetic near-fields, I demonstrate the extension of s-SNOM techniques through the implementation of a heated atomic force microscope (AFM) tip acting as its own intrinsic light source for the characterization of thermal near-fields. Here, I detail the spectrally distinct and orders of magnitude enhanced resonant spectral near-field energy density associated with vibrational, phonon, and phonon-polariton modes. Modeling the thermal light scattering by the AFM, the scattering cross-section for thermal light may be related to the electromagnetic local density of states (EM-LDOS) above a surface. Lastly, the unique capability of s-SNOM techniques to characterize phase separation phenomena in correlated electron systems is discussed. This measurement capability provides new microscopic insight into the underlying mechanisms of the rich phase transition behavior exhibited by these materials. As a specific example, the infrared s-SNOM mapping of the metal-insulator transition and the associated nano-domain formation in individual VO2 micro-crystals subject to substrate stress is presented. Our results have important implications for the interpretation of the investigations of conventional polycrystalline thin films where the mutual interaction of constituent crystallites may affect the nature of phase separation processes.

  10. Spectrophotometric determination of ascorbic acid by the modified CUPRAC method with extractive separation of flavonoids-La(III) complexes. (United States)

    Ozyürek, Mustafa; Güçlü, Kubilay; Bektaşoğlu, Burcu; Apak, Reşat


    The proposed method for ascorbic acid: AA (Vitamin C) determination is based on the oxidation of AA to dehydroascorbic acid with the CUPRAC reagent of total antioxidant capacity assay, i.e., Cu(II)-neocuproine (Nc), in ammonium acetate-containing medium at pH 7, where the absorbance of the formed bis(Nc)-copper(I) chelate is measured at 450 nm. The flavonoids (essentially flavones and flavonols) normally interfering with the CUPRAC procedure were separated with preliminary extraction as their La(III) chelates into ethylacetate (EtAc). The Cu(I)-Nc chelate responsible for color development was formed immediately with AA oxidation. Beer's law was obeyed between 8.0 x 10(-6) and 8.0 x 10(-5) M concentration range, with the equation of the linear calibration curve: A(450 nm)=1.60 x 10(4)C (mol dm(-3))-0.0596. The relative standard deviation (R.S.D.) in the analysis of N=45 synthetic mixtures containing 1.25 x 10(-2) mM AA with flavonoids was 5.3%. The Cu(II)-Nc reagent is a lower redox-potential and therefore more selective oxidant than the Fe(III)-1,10-phenanthroline reagent conventionally used for the same assay. This feature makes the proposed method superior for real samples such as fruit juices containing weak reductants such as citrate, oxalate and tartarate that may otherwise produce positive errors in the Fe(III)-phen method when equilibrium is achieved. The developed method was applied to some commercial fruit juices and pharmaceutical preparations containing Vitamin C+bioflavonoids. The findings of the developed method for fruit juices and pharmaceuticals were statistically alike with those of HPLC. The proposed spectrophotometric method was practical, low-cost, rapid, and could reliably assay AA in the presence of flavonoids without enzymatic procedures open to interferences by enzyme inhibitors.

  11. Interfacial charge separation and recombination in InP and quasi-type II InP/CdS core/shell quantum dot-molecular acceptor complexes. (United States)

    Wu, Kaifeng; Song, Nianhui; Liu, Zheng; Zhu, Haiming; Rodríguez-Córdoba, William; Lian, Tianquan


    Recent studies of group II-VI colloidal semiconductor heterostuctures, such as CdSe/CdS core/shell quantum dots (QDs) or dot-in-rod nanorods, show that type II and quasi-type II band alignment can facilitate electron transfer and slow down charge recombination in QD-molecular electron acceptor complexes. To explore the general applicability of this wave function engineering approach for controlling charge transfer properties, we investigate exciton relaxation and dissociation dynamics in InP (a group III-V semiconductor) and InP/CdS core/shell (a heterostructure beween group III-V and II-VI semiconductors) QDs by transient absorption spectroscopy. We show that InP/CdS QDs exhibit a quasi-type II band alignment with the 1S electron delocalized throughout the core and shell and the 1S hole confined in the InP core. In InP-methylviologen (MV(2+)) complexes, excitons in the QD can be dissociated by ultrafast electron transfer to MV(2+) from the 1S electron level (with an average time constant of 11.4 ps) as well as 1P and higher electron levels (with a time constant of 0.39 ps), which is followed by charge recombination to regenerate the complex in its ground state (with an average time constant of 47.1 ns). In comparison, InP/CdS-MV(2+) complexes show similar ultrafast charge separation and 5-fold slower charge recombination rates, consistent with the quasi-type II band alignment in these heterostructures. This result demonstrates that wave function engineering in nanoheterostructures of group III-V and II-VI semiconductors provides a promising approach for optimizing their light harvesting and charge separation for solar energy conversion applications.

  12. Influence of ionic liquids as electrolyte additives on chiral separation of dansylated amino acids by using Zn(II) complex mediated chiral ligand exchange CE. (United States)

    Zhang, Haizhi; Qi, Li; Mu, Xiaoyu; Zhou, Xiaoping; Li, Dan; Mao, Lanqun


    In this work, investigation of the comparative influence of diverse ionic liquids (ILs) as electrolyte additives on the chiral separation of dansylated amino acids by using Zn(II)-L-arginine complex mediated chiral ligand exchange CE (CLE-CE) was conducted. It has been found that not only the varied substituted group number, but also the alkyl chain length of the substituted group on imidazole ring in the structure of ILs show different influence on chiral separation of the analytes in the CLE-CE system, which could be understood by their direct influence on EOF. Meanwhile, the variation of anion in the structure of ILs displayed remarkably changed performance and the ILs with Cl(-) showed the most obvious promoting effect on the chiral separation performance. Among the investigated seven ILs, 1-butyl-3-methylimidazolium chloride was validated to be the proper electrolyte additive in the CLE-CE system. Moreover, it has been observed that 1-butyl-3-methylimidazolium chloride also has obvious promotive effect on the labeling performance. The results have demonstrated that the ILs with different structures have important relation to their performance in CLE-CE and to their labeling efficiency in dansylation of the analytes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. New reversed phase-high performance liquid chromatographic method for selective separation of yttrium from all rare earth elements employing nitrilotriacetate complexes in anion exchange mode. (United States)

    Dybczyński, Rajmund S; Kulisa, Krzysztof; Pyszynska, Marta; Bojanowska-Czajka, Anna


    Separation of Y from other rare earth elements (REE) is difficult because of similarity of its ionic radius to ionic radii of Tb, Dy and Ho. In the new RP-HPLC system with C18 column, tetra-n-butyl ammonium hydroxide (TBAOH) as an ion interaction reagent (IIR), nitrilotriacetic acid (NTA) as a complexing agent at pH=2.8-3.5, and post column derivatization with Arsenazo III, yttrium is eluted in the region of light REE, between Nd and Sm and is base line separated from Nd and Sm and even from promethium. Simple model employing literature data on complex formation of REE with NTA and based on anion exchange mechanism was developed to foresee the order of elution of individual REE. The model correctly predicted that lanthanides up to Tb will be eluted in the order of increasing Atomic Number (At.No.) but all heavier REE will show smaller retention factors than Tb. Concurrent UV/VIS detection at 658nm and the use of radioactive tracers together with γ-ray spectrometric measurements made possible to establish an unique elution order of elution of REE: La, Ce, Pr, Nd, Pm, Y, Sm, Er, Ho, Tm, Yb, Eu, Lu, Dy+Gd, Tb, Sc. The real place of Y however, in this elution series differs from that predicted by the model (Y between Sm and Eu). The method described in this work enables selective separation of Y from La, Ce, Pr, Nd, Pm, Sm and all heavier REE treated as a group. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Dynamics in one complex variable (AM-160)

    CERN Document Server

    Milnor, John


    This volume studies the dynamics of iterated holomorphic mappings from a Riemann surface to itself, concentrating on the classical case of rational maps of the Riemann sphere. This subject is large and rapidly growing. These lectures are intended to introduce some key ideas in the field, and to form a basis for further study. The reader is assumed to be familiar with the rudiments of complex variable theory and of two-dimensional differential geometry, as well as some basic topics from topology. This third edition contains a number of minor additions and improvements: A historical survey has b

  15. Vector bundles on complex projective spaces

    CERN Document Server

    Okonek, Christian; Spindler, Heinz


    This expository treatment is based on a survey given by one of the authors at the Séminaire Bourbaki in November 1978 and on a subsequent course held at the University of Göttingen. It is intended to serve as an introduction to the topical question of classification of holomorphic vector bundles on complex projective spaces, and can easily be read by students with a basic knowledge of analytic or algebraic geometry. Short supplementary sections describe more advanced topics, further results, and unsolved problems.

  16. Understanding the complexation of Eu3 + with potential ligands used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle: A luminescence investigation (United States)

    Sengupta, Arijit; Kadam, R. M.


    A systematic photoluminescence based investigation was carried out to understand the complexation of Eu3 + with different ligands (TBP: tri-n-butyl phosphate, DHOA: di-n-hexyl octanamide, Cyanex 923: tri-n-alkyl phosphine oxide and Cyanex 272: Bis (2,4,4 trimethyl) pentyl phosphinic acid) used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle. In case of TBP and DHOA complexes, 3 ligand molecules coordinated in monodentate fashion and 3 nitrate ion in bidentate fashion to Eu3 + to satisfy the 9 coordination of Eu. In case of Cyanex 923 and Cyanex 272 complexes, 3 ligand molecules, 3 nitrate ion and 3 water molecules coordinated to Eu3 + in monodentate fashion. The Eu complexes of TBP and DHOA were found to have D3h local symmetry while that for Cyanex 923 and Cyanex 272 were C3h. Judd-Ofelt analysis of these systems revealed that the covalency of Eusbnd O bond followed the trend DHOA > TBP > Cyanex 272 > Cyanex 923. Different photophysical properties like radiative and non-radiative life time, branching ratio for different transitions, magnetic and electric dipole moment transition probabilities and quantum efficiency were also evaluated and compared for these systems. The magnetic dipole transition probability was found to be almost independent of ligand field perturbation while electric dipole transition probability for 5D0-7F2 transition was found to be hypersensitive with ligand field with a trend DHOA > TBP > Cyanex 272 > Cyanex 923. Supplementary Table 2: Determination of inner sphere water molecules from the different empirical formulae reported in the literature.

  17. [Chiral separation of five beta-blockers using di-n-hexyl L-tartrate-boric acid complex as mobile phase additive by reversed-phase liquid chromatography]. (United States)

    Yang, Juan; Wang, Lijuan; Guo, Qiaoling; Yang, Gengliang


    A reversed-phase high performance liquid chromatographic (HPLC) method using the di-n-hexyl L-tartrate-boric acid complex as a chiral mobile phase additive was developed for the enantioseparation of five beta-blockers including propranolol, esmolol, metoprolol, bisoprolol and sotalol. In order to obtain a better enantioseparation, the influences of concentrations of di-n-butyl L-tartrate and boric acid, the type, concentration and pH of the buffer, methanol content as well as the molecular structure of analytes were extensively investigated. The separation of the analytes was performed on a Venusil MP-C18 column (250 mm x 4.6 mm, 5 microm). The mobile phase was 15 mmol/L ammonium acetate-methanol containing 60 mmol/L boric acid, 70 mmol/L di-n-hexyl L-tartrate (pH 6.00). The volume ratios of 15 mmol/L ammonium acetate to methanol were 20: 80 for propranolol, esmolol, metoprolol, bisoprolol and 30: 70 for sotalol. The flow rate was 0.5 mL/min and the detection wavelength was set at 214 nm. Under the optimized conditions, baseline enantioseparation was obtained separately for the five pairs of analytes.

  18. Separation and determination of abused drugs clenbuterol and salbutamol from complex extractants in swine feed by capillary zone electrophoresis with simple pretreatment. (United States)

    Chen, Qian; Fan, Liu-Yin; Zhang, Wei; Cao, Cheng-Xi


    A simple but efficient capillary zone electrophoresis (CZE) method was developed for the fast separation and determination of two misused beta2-agonists clenbuterol (CLB) and salbutamol (SAL) from complex background extractants existing in swine feed samples. The proper experimental conditions were achieved as 20.0 mmol/l pH 10.5 Na(2)HPO(4)-NaOH buffer, 20 kV applied voltage, fused-silica capillary of 60.5 cm x 75 microm i.d. (50 cm to detector). Under the proper conditions, the two abused drugs can be online isolated from the complex extractants and the separation between CLB and SAL is good, all of the target analytes can be detected within 4.5 min. The linear response of CLB and SAL concentration ranges from 2.0 to 100.0 microg/ml with high correlation coefficient (R(2)=0.9990) and (R(2)=0.9986), respectively. Limit of detection (LOD) and limit of quantification (LOQ) was calculated to be 0.95 and 3.17 microg/ml for CLB, 1.07 and 3.57 microg/ml for SAL. The precision values (expressed as R.S.D.) of intra- and inter-day were 1.24-2.36% and 0.90-3.85% for CLB, 0.47-1.64% and 0.91-3.46% for SAL. Recoveries spiked at levels 5.0, 25.0, 80.0 microg/ml ranged between 93.30% and 104.33% with R.S.D. less than 5%. Finally, the developed method has been applied to the analysis of real swine feed samples and has achieved satisfactory results.

  19. Complex phase separation in poly(acrylonitrile-butadiene-styrene)-modified epoxy/4,4'-diaminodiphenyl sulfone blends: generation of new micro- and nanosubstructures. (United States)

    Jyotishkumar, P; Koetz, Joachim; Tiersch, Brigitte; Strehmel, Veronika; Ozdilek, Ceren; Moldenaers, Paula; Hässler, Rudiger; Thomas, Sabu


    The epoxy system containing diglycidyl ether of bisphenol A and 4,4'-diaminodiphenyl sulfone is modified with poly(acrylonitrile-butadiene-styrene) (ABS) to explore the effects of the ABS content on the phase morphology, mechanism of phase separation, and viscoelastic properties. The amount of ABS in the blends was 5, 10, 15, and 20 parts per hundred of epoxy resin (phr). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were employed to investigate the final morphology of ABS-modified epoxy blends. Scanning electron microscopic studies of 15 phr ABS-modified epoxy blends reveal a bicontinuous structure in which both epoxy and ABS are continuous, with substructures of the ABS phase dispersed in the continuous epoxy phase and substructures of the epoxy phase dispersed in the continuous ABS phase. TEM micrographs of 15 phr ABS-modified epoxy blends confirm the results observed by SEM. TEM micrographs reveal the existence of nanosubstructures of ABS in 20 phr ABS-modified epoxy blends. To the best of our knowledge, to date, nanosubstructures have never been reported in any epoxy/thermoplastic blends. The influence of the concentration of the thermoplastic on the generated morphology as analyzed by SEM and TEM was explained in detail. The evolution and mechanism of phase separation was investigated in detail by optical microscopy (OM) and small-angle laser light scattering (SALLS). At concentrations lower than 10 phr the system phase separates through nucleation and growth (NG). However, at higher concentrations, 15 and 20 phr, the blends phase separate through both NG and spinodal decomposition mechanisms. On the basis of OM and SALLS, we conclude that the phenomenon of complex substructure formation in dynamic asymmetric blends is due to the combined effect of hydrodynamics and viscoelasticity. Additionally, dynamic mechanical analysis was carried out to evaluate the viscoelastic behavior of the cross-linked epoxy/ABS blends. Finally

  20. Low support for separate species within the redpoll complex (Carduelis flammea-hornemanni-cabaret) from analyses of mtDNA and microsatellite markers. (United States)

    Marthinsen, Gunnhild; Wennerberg, Liv; Lifjeld, Jan T


    The redpoll complex, consisting of three currently recognized species (Carduelis flammea, C. hornemanni and C. cabaret), is polytypic in biometry, morphology, physiology and behaviour. However, previous genetic work has not revealed any indications of genetic differentiation. We analysed sequence variation in the mtDNA control region, and allele frequencies of supposedly faster evolving microsatellites (n=10), in an attempt to detect molecular genetic support for the three species, as well as two subspecies of C. flammea (ssp. flammea and rostrata), within this complex. We used samples from two subspecies of the twite (Carduelis flavirostris, ssp. flavirostris and rufostrigata) as outgroup. We found no structure among redpoll individuals in mtDNA haplotypes or microsatellite allele frequencies, and only marginal differences between redpoll taxa in analyses of molecular variance (AMOVAs) of predefined groups. In contrast, the two twite subspecies constituted two well-supported monophyletic groups. Our study thus strengthens previous indications of low genetic support for current redpoll taxa. Two major alternative interpretations exist. Either redpolls form a single gene pool with geographical polymorphisms possibly explained by Bergmann's and Gloger's rules, or there are separate gene pools of recent origin but with too little time elapsed for genetic differentiation to have evolved in the investigated markers. Future studies should therefore examine whether reproductive isolation mechanisms and barriers to gene flow exist in areas with sympatric breeding.

  1. Enantiomeric separation of seven β-agonists by NACE-Study of chiral selectivity with diacetone-d-mannitol-boric acid complex. (United States)

    Lv, Lili; Wang, Lijuan; Li, Jun; Jiao, Yajun; Gao, Shengnan; Wang, Jiachang; Yan, Hongyuan


    A rapid and effective nonaqueous capillary electrophoresis (NACE)-ultraviolet (UV) method was developed for the enantiomeric separation of seven β-agonists. Diacetone-d-mannitol-boric acid complex was used as a new chiral selector. It was in situ synthesized by the reaction of diacetone-d-mannitol and boric acid in methanol medium containing triethylamine. The effects of diacetone-d-mannitol, boric acid, and triethylamine concentrations on the enantioseparation were carefully investigated. Under the optimized conditions, baseline enantioseparation could be obtained for six of the tested β-agonists within 12min. These results were better than that obtained with d-mannitol-boric acid complex in previous work. 11B nuclear magnetic resonance (11B NMR) was applied to determine the fraction of boron species and confirm the formation of diacetone-d-mannitol-boric acid complex. Validation of the established NACE method was also carried out according to ICH guidelines. Calibration curves showed good linearity with correlation coefficients (r)≥0.9992 over a certain concentration range for each enantiomer of the tested five β-agonists. The relative standard deviations (RSDs) of intra-day precisions and inter-day precisions of migration times were ≤1.4% (n=6), and ≤6.3% (n=10), respectively. That of peak areas were ≤3.7% (n=6), and ≤5.6% (n=10), respectively. The limits of detection (LODs) and the limits of quantitation (LOQs) based on the signal-to-noise ratios of 3 and 10 were found below 1.25μgmL-1 and 5.00μgmL-1, respectively. The proposed method was successfully applied to the determination of clenbuterol enantiomers in a multi-component pharmaceutical dosage form called "Ambroxol Hydrochloride and Clenbuterol Hydrochloride Oral Solution". Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Complexity

    Indian Academy of Sciences (India)

    Rahul Pandit


    Oct 31, 2008 ... ”The more complex a thing is, the more you can talk about it.” - attributed to Giorgio Parisi. ▻ ”C'est magnifique, mais ce n'est pas de la science.” (It is magnificent, but not all of it is science.) - attributed ... Earliest examples: theoretical computer science, algorithmic complexity, etc. ▻ Rapid progress after the ...

  3. PVDF-ErGO-GRC electrode: A single setup electrochemical system for separation, pre-concentration and detection of lead ions in complex aqueous samples. (United States)

    Hamsawahini, Kunashegaran; Sathishkumar, Palanivel; Ahamad, Rahmalan; Yusoff, Abdull Rahim Mohd


    An effective electrode was developed based on electromembrane extraction (EME) and square wave voltammetry (SWV) for simultaneous separation, pre-concentration and determination of lead (II) (Pb(II)) ions in complex aqueous samples. Electrochemically reduced graphene oxide-graphite reinforced carbon (ErGO-GRC) was utilized in conjunction with the SWV. Pb(II) ions were extracted from an aqueous sample solution into an acidic acceptor phase (1M HCl) in the lumen of the polyvinylidene fluoride (PVDF) membrane bag by the application of voltage of maximum 6 V across the supported liquid membrane (SLM), consisting of organic solvent and di-(2-ethylhexyl)phosphoric acid (D2EHPA). The parameters affecting the EME were optimized for Pb(II) ions. The optimum EME conditions were found to be 20% D2EHPA in 1-octanol impregnated in the wall of PVDF membrane (PVDF17) as the SLM, extraction time of 20 min, pH of sample solution of 8 and a voltage of 5 V. The PVDF-ErGO-GRC electrode system attained enrichment factors of 40 times and 80% of extraction with relative standard deviations (n=5) of 8.3%. Good linearity ranging from 0.25 to 2 nM with coefficients correlation of 0.999 was obtained. The Pb(II) ions detection limit of PVDF-ErGO-GRC electrode was found to be 0.09 nM. The newly developed single setup electrochemical system was applied to complex aqueous samples such as tap, river and sea water to evaluate the feasibility of the method for applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Complete Monitoring of Coherent and Incoherent Spin Flip Domains in the Recombination of Charge-Separated States of Donor-Iridium Complex-Acceptor Triads. (United States)

    Klein, Johannes H; Schmidt, David; Steiner, Ulrich E; Lambert, Christoph


    The spin chemistry of photoinduced charge-separated (CS) states of three triads comprising one or two triarylamine donors, a cyclometalated iridium complex sensitizer and a naphthalene diimide (NDI) acceptor, was investigated by transient absorption spectroscopy in the ns-μs time regime. Strong magnetic-field effects (MFE) were observed for two triads with a phenylene bridge between iridium complex sensitizer and NDI acceptor. For these triads, the lifetimes of the CS states increased from 0.6 μs at zero field to 40 μs at about 2 T. Substituting the phenylene by a biphenyl bridge causes the lifetime of the CS state at zero field to increase by more than 2 orders of magnitude (τ = 79 μs) and the MFE to disappear almost completely. The kinetic MFE was analyzed in the framework of a generalized Hayashi-Nagakura scheme describing coherent (S, T0 ↔ T±) as well as incoherent (S, T0 ⇌ T±) processes by a single rate constant k±. The magnetic-field dependence of k± of the triads with phenylene bridge spans 2 orders of magnitude and exhibits a biphasic behavior characterized by a superposition of two Lorentzians. This biphasic MFE is observed for the first time and is clearly attributable to the coherent (B < 10 mT) and incoherent (10 mT < B < 2 T) domains of spin motion induced by isotropic and anisotropic hyperfine coupling. The parameters of both domains are well understood in terms of the structural properties of the two triads, including the effect of electron hopping in the triad with two donor moieties. The kinetic model also accounts for the reduction of the MFE on reducing the rate constant of charge recombination in the triad with the biphenyl bridge.

  5. Separated Shoulder (United States)

    ... an injury to the ligaments that hold your collarbone (clavicle) to your shoulder blade. In a mild separated ... tenderness or pain near the end of your collarbone. Causes The most common cause of a separated ...


    Skarstrom, C.


    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  7. Quest for Environmentally-Benign Ligands for Actinide Separations: Thermodynamic, Spectroscopic, and Structural Characterization of U(VI) Complexes with Oxa-Diamide and Related Ligands

    Energy Technology Data Exchange (ETDEWEB)

    Advanced Light Source; Tian, Guoxin; Rao, Linfeng; Teat, Simon J.; Liu, Guokui


    Complexation of U(VI) with N,N,N{prime},N{prime}-tetramethyl-3-oxa-glutaramide (TMOGA) and N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) was studied in comparison with their dicarboxylate analog, oxydiacetic acid (ODA). Thermodynamic parameters, including stability constants, enthalpy and entropy of complexation, were determined by spectrophotometry, potentiometry and calorimetry. Single-crystal X-ray diffractometry, EXAFS spectroscopy, FT-IR absorption and laser-induced luminescence spectroscopy were used to obtain structural information on the U(VI) complexes. Like ODA, TMOGA and DMOGA form tridentate U(VI) complexes, with three oxygen atoms (the amide, ether and/or carboxylate oxygen) coordinating to the linear UO{sub 2}{sup 2+} cation via the equatorial plane. The stability constants, enthalpy and entropy of complexation all decrease in the order ODA > DMOGA > TMOGA, showing that the complexation is entropy driven and the substitution of a carboxylate group with an amide group reduces the strength of complexation with U(VI) due to the decrease in the entropy of complexation. The trend in the thermodynamic stability of the complexes correlates very well with the structural and spectroscopic data obtained by single crystal XRD, FT-IR and laser-induced luminescence spectroscopy.

  8. Separation-of-function mutation in HPC2, a member of the HIR complex in S. cerevisiae, results in derepression of the histone genes but does not confer cryptic TATA phenotypes. (United States)

    Vishnoi, Nidhi; Flaherty, Kacie; Hancock, Leandria C; Ferreira, Monica E; Amin, Amit Dipak; Prochasson, Philippe


    The HIR complex, which is comprised of the four proteins Hir1, Hir2, Hir3 and Hpc2, was first characterized as a repressor of three of the four histone gene loci in Saccharomyces cerevisiae. Using a bioinformatical approach, previous studies have identified a region of Hpc2 that is conserved in Schizosaccharomyces pombe and humans. Using a similar approach, we identified two additional domains, CDI and CDII, of the Hpc2 protein that are conserved among yeast species related to S. cerevisiae. We showed that the N terminal CDI domain (spanning amino acids 63-79) is dispensable for HIR complex assembly, but plays an essential role in the repression of the histone genes by recruiting the HIR complex to the HIR-dependent histone gene loci. The second conserved domain, CDII (spanning amino acids 452-480), is required for the stability of the Hpc2 protein itself as well as for the assembly of the HIR complex. In addition, we report a novel separation-of-function mutation within CDI of Hpc2, which causes derepression of the histone genes but does not confer other reported hir/hpc- phenotypes (such as Spt phenotypes, heterochromatin silencing defects and repression of cryptic promoters). This is the first direct demonstration that a separation-of-function mutation exists within the HIR complex. 2011 Elsevier B.V. All rights reserved.

  9. Isotope separation (United States)

    Bartlett, Rodney J.; Morrey, John R.


    A method and apparatus is described for separating gas molecules containing one isotope of an element from gas molecules containing other isotopes of the same element in which all of the molecules of the gas are at the same electronic state in their ground state. Gas molecules in a gas stream containing one of the isotopes are selectively excited to a different electronic state while leaving the other gas molecules in their original ground state. Gas molecules containing one of the isotopes are then deflected from the other gas molecules in the stream and thus physically separated.

  10. ISOTOPE SEPARATORS (United States)

    Bacon, C.G.


    An improvement is presented in the structure of an isotope separation apparatus and, in particular, is concerned with a magnetically operated shutter associated with a window which is provided for the purpose of enabling the operator to view the processes going on within the interior of the apparatus. The shutier is mounted to close under the force of gravity in the absence of any other force. By closing an electrical circuit to a coil mouated on the shutter the magnetic field of the isotope separating apparatus coacts with the magnetic field of the coil to force the shutter to the open position.

  11. Dinuclear manganese(II) complexes of hexaazamacrocycles bearing N-benzoylated pendant separated by aromatic spacers: Antibacterial, DNA interaction, cytotoxic and molecular docking studies. (United States)

    Arthi, P; Shobana, S; Srinivasan, P; Prabhu, D; Arulvasu, C; Kalilur Rahiman, A


    Three new homodinuclear manganese(II) complexes of the type [Mn2L(1-3)(ClO4)(H2O)](ClO4)3 (1-3) have been synthesized via cyclocondensation of terephthalaldehyde with three different benzoylated pendants in the presence of manganese(II) perchlorate and characterized by spectroscopic methods. Cyclic voltammetric investigation of complexes (1-3) depict two quasi-reversible one electron reduction processes in the cathodic potential region (E(1)pc=-0.73 to-0.83 V, E(2)pc=-1.31 to -1.40 V) and two quasi-reversible one electron oxidation processes in the anodic potential region (E(1)pa=1.03 to 1.10 V, E(2)pa=1.69 to 1.77 V). Electronic absorption spectra of the complexes suggested tetrahedral geometry around the central metal ion. The observed low magnetic moment values (μeff, 5.60-5.68 B.M.) of the complexes indicate the presence of an antiferromagnetic spin-exchange interaction between two metal centers, which was also supported by the broad EPR signal. All the compounds were tested for antibacterial activity against Gram (-ve) and Gram (+ve) bacterial strains. The binding studies of complexes with CT-DNA suggested minor-groove mode of interaction. Molecular docking studies were carried out in order to find the binding affinity of complexes with DNA and protein EGFR Kinase. The complexes are stabilized by additional electrostatic and van der Waals interaction with the DNA, and support minor groove mode of binding. The cleavage activity of complexes on pBR322 plasmid DNA displays efficient activity through a mechanistic pathway involving hydroxyl radicals. The cytotoxicity of complexes 2 and 3 have been tested against human liver adenocarcinoma (HepG2) cell line. Nuclear-chromatin cleavage has also been observed with propidium iodide (PI) staining and alkaline single-cell gel electrophoresis (comet assay) techniques. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Separation of Gd-humic complexes and Gd-based magnetic resonance imaging contrast agent in river water with QAE-Sephadex A-25 for the fractionation analysis. (United States)

    Matsumiya, Hiroaki; Inoue, Hiroto; Hiraide, Masataka


    Gadolinium complexed with naturally occurring, negatively charged humic substances (humic and fulvic acids) was collected from 500 mL of sample solution onto a column packed with 150 mg of a strongly basic anion-exchanger (QAE-Sephadex A-25). A Gd-based magnetic resonance imaging contrast agent (diethylenetriamine-N,N,N',N″,N″-pentaacetato aquo gadolinium(III), Gd-DTPA(2-)) was simultaneously collected on the same column. The Gd-DTPA complex was desorbed by anion-exchange with 50mM tetramethylammonium sulfate, leaving the Gd-humic complexes on the column. The Gd-humic complexes were subsequently dissociated with 1M nitric acid to desorb the humic fraction of Gd. The two-step desorption with small volumes of the eluting agents allowed the 100-fold preconcentration for the fractionation analysis of Gd at low ng L(-1) levels by inductively coupled plasma-mass spectrometry (ICP-MS). On the other hand, Gd(III) neither complexed with humic substances nor DTPA, i.e., free species, was not sorbed on the column. The free Gd in the effluent was preconcentrated 100-fold by a conventional solid-phase extraction with an iminodiacetic acid-type chelating resin and determined by ICP-MS. The proposed analytical fractionation method was applied to river water samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. HRS Separator

    CERN Multimedia


    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  14. GPS Separator

    CERN Multimedia


    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  15. Separation system (United States)

    Rubin, Leslie S.


    A separation system for dewatering radioactive waste materials includes a disposal container, drive structure for receiving the container, and means for releasably attaching the container to the drive structure. Separation structure disposed in the container adjacent the inner surface of the side wall structure retains solids while allowing passage of liquids. Inlet port structure in the container top wall is normally closed by first valve structure that is centrifugally actuated to open the inlet port and discharge port structure at the container periphery receives liquid that passes through the separation structure and is normally closed by second valve structure that is centrifugally actuated to open the discharge ports. The container also includes coupling structure for releasable engagement with the centrifugal drive structure. Centrifugal force produced when the container is driven in rotation by the drive structure opens the valve structures, and radioactive waste material introduced into the container through the open inlet port is dewatered, and the waste is compacted. The ports are automatically closed by the valves when the container drum is not subjected to centrifugal force such that containment effectiveness is enhanced and exposure of personnel to radioactive materials is minimized.

  16. Gas separating (United States)

    Gollan, A.


    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing. 3 figs.

  17. Flow Separation (United States)


    perfomanoas que oette oirconstance peut entrainer, soit encore, d’un point de vue plus fondamental par la recherche dM phenomknas qui caracterisent 1M...dtfoolleoent, dont le m^canlsme de formation eat en tout point sen- blable h celui qui a etc döcrit § 2.2. XL se caracterise par la presence d’une onde...during orbital maneuvers with the Reaction Control System (RCS) and later plume induced separation leading to aerodynamic heating and control problems

  18. Lectures on several complex variables

    CERN Document Server

    Gauthier, Paul M


    This monograph provides a concise, accessible snapshot of key topics in several complex variables, including the Cauchy Integral Formula, sequences of holomorphic functions, plurisubharmonic functions, the Dirichlet problem, and meromorphic functions.  Based on a course given at Université de Montréal, this brief introduction covers areas of contemporary importance that are not mentioned in most treatments of the subject, such as modular forms, which are essential for Wiles' theorem and the unification of quantum theory and general relativity.   Also covered is the Riemann manifold of a function, which generalizes the Riemann surface of a function of a single complex variable and is a topic that is well-known in one complex variable, but rarely treated in several variables.  Many details, which are intentionally left out, as well as many theorems are stated as problems, providing students with carefully structured instructive exercises.   Prerequisites for use of this book are functions of one complex ...

  19. A nuclear single-nucleotide polymorphism (SNP) potentially useful for the separation of Rhodnius prolixus from members of the Rhodnius robustus cryptic species complex (Hemiptera: Reduviidae) (United States)

    Pavan, Márcio G.; Mesquita, Rafael D.; Lawrence, Gena G.; Lazoski, Cristiano; Dotson, Ellen M.; Abubucker, Sahar; Mitreva, Makedonka; Randall-Maher, Jennifer; Monteiro, Fernando A.


    The design and application of rational strategies that rely on accurate species identification are pivotal for effective vector control. When morphological identification of the target vector species is impractical, the use of molecular markers is required. Here we describe a non-coding, single-copy nuclear DNA fragment that contains a single-nucleotide polymorphism (SNP) with the potential to distinguish the important domestic Chagas disease vector, Rhodnius prolixus, from members of the four sylvatic Rhodnius robustus cryptic species complex. A total of 96 primer pairs obtained from whole genome shotgun sequencing of the R. prolixus genome (12,626 random reads) were tested on 43 R. prolixus and R. robustus s.l. samples. One of the seven amplicons selected (AmpG) presented a SNP, potentially diagnostic for R. prolixus, on the 280th site. The diagnostic nature of this SNP was then performed on 154 R. prolixus and R. robustus s.l. samples aimed at achieving the widest possible geographic coverage. The results of a 60% majority rule Bayesian consensus tree and a median-joining network constructed based on the genetic variability observed reveal the paraphyletic nature of the R. robustus species complex, with respect to R. prolixus. AmpG region is located in the fourth intron of the Transmembrane protein 165 gene, which seems to be in the R. prolixus X chromosome. Other possible chromosomal locations of the AmpG region in the R. prolixus genome are also presented and discussed. PMID:23219914

  20. Differentiation in stag beetles, Neolucanus swinhoei complex (Coleoptera: Lucanidae): four major lineages caused by periodical Pleistocene glaciations and separation by a mountain range. (United States)

    Tsai, Cheng-Lung; Wan, Xia; Yeh, Wen-Bin


    Taxonomic debates on Neolucanus swinhoei complex consisting of N. swinhoei, N. doro doro, N. doro horaguchii, and N. euganiae, distributed exclusively in Taiwan, have been ongoing for several decades because of their overlapping morphological characters. To clarify their taxonomic status and phylogeographical history, we analyzed nine morphological characteristics and four molecular amplicons. Phylogenetic inferences based on COI+16S rDNA+wingless showed one eastern and three western lineages, with the latter consisting of one low-hill and two montane lineages. Intermingled DNA sequences from different populations within each lineage, many low FST values, and a high variance component between lineages indicate the possibility of gene flow among populations. However, positive relationships were observed between the genetic divergences of 16S rDNA and its FST values with geographic distance. A divergence estimation based on COI+16S revealed that these beetles might have originated from Asian mainland and differentiated into western and eastern lineages ca. 1Mya, with the differentiation of the western lineages occurring approximately 0.50-0.75Mya. Isolation by mountain ranges and limited flying capability of these beetles as well as populations retreat to and expansion from refugia in response to glaciation cycles have resulted in the current distribution of N. swinhoei complex. Although most morphological characters are variable and undistinguishable, multi-dimensional scaling analysis based on measurable characteristics could recognize hill N. swinhoei as a cluster distinct from the others. However, based on the realities of genetic admixture, shared phylogeographical history and overlapping characteristics, all of these stag beetles should be regarded as Neolucanus swinhoei Bates, 1866. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Learning Separable Filters. (United States)

    Sironi, Amos; Tekin, Bugra; Rigamonti, Roberto; Lepetit, Vincent; Fua, Pascal


    Learning filters to produce sparse image representations in terms of over-complete dictionaries has emerged as a powerful way to create image features for many different purposes. Unfortunately, these filters are usually both numerous and non-separable, making their use computationally expensive. In this paper, we show that such filters can be computed as linear combinations of a smaller number of separable ones, thus greatly reducing the computational complexity at no cost in terms of performance. This makes filter learning approaches practical even for large images or 3D volumes, and we show that we significantly outperform state-of-the-art methods on the curvilinear structure extraction task, in terms of both accuracy and speed. Moreover, our approach is general and can be used on generic convolutional filter banks to reduce the complexity of the feature extraction step.

  2. Generic Separations and Leaf Languages


    Matthias Galota; Sven Kosub (Hrsg.); Heribert Vollmer


    In the early nineties of the previous century, leaf languages were introduced as a means for the uniform characterization of many complexity classes, mainly in the range between P (polynomial time) and PSPACE (polynomial space). It was shown that the separability of two complexity classes can be reduced to a combinatorial property of the corresponding defining leaf languages. In the present paper, it is shown that every separation obtained in this way holds for every generic oracle in the sen...

  3. Kodaira-Spencer deformation of complex structures and Lagrangian field theory (United States)

    Bandelloni, Giuseppe; Lazzarini, Serge


    Similar to the Beltrami parametrization of complex structures on a (compact) Riemann surface, we use in this paper the Kodaira-Spencer deformation theory of complex structures on a (compact) complex manifold of higher dimension. According to the Newlander-Nirenberg theorem, a smooth change of local complex coordinates is implemented with respect to an integrable complex structure parametrize by a Beltrami differential. The question of constructing a local field theory on a complex compact manifold is addressed and the action of smooth diffeomorphisms is studied in the BRS algebraic approach. The BRS cohomology for the diffeomorphisms gives generalized Gel'fand-Fuchs cocycles provided that the Kodaira-Spencer integrability condition is satisfied. The diffeomorphism anomaly is computed and turns out to be holomorphically split as in the bidimensional Lagrangian conformal models. Moreover, its algebraic structure is much more complicated than the one proposed in a recent paper [Losev et al. Nuc. Phys. B 484, 196 (1997)].

  4. Equations hessiennes complexes sur des variétés kählériennes compactes


    Jbilou, Asma


    On a compact connected 2m-dimensional Kähler manifold with Kähler form !, given a volume form ­ 2 [!]m and an integer 1 < k < m, we want to solve uniquely in [!] the equation ˜ !k ^!m−k = ­, relying on the notion of k-positivity for ˜ ! 2 [!] (the extreme cases are solved : k = m by Yau, k = 1 trivially). We solve by the continuity method the corresponding complex elliptic k-th Hessian equation under the assumption that the holomorphic bisectional curvature of the manifold is non-negative, re...

  5. Separable programming theory and methods

    CERN Document Server

    Stefanov, Stefan M


    In this book, the author considers separable programming and, in particular, one of its important cases - convex separable programming Some general results are presented, techniques of approximating the separable problem by linear programming and dynamic programming are considered Convex separable programs subject to inequality equality constraint(s) and bounds on variables are also studied and iterative algorithms of polynomial complexity are proposed As an application, these algorithms are used in the implementation of stochastic quasigradient methods to some separable stochastic programs Numerical approximation with respect to I1 and I4 norms, as a convex separable nonsmooth unconstrained minimization problem, is considered as well Audience Advanced undergraduate and graduate students, mathematical programming operations research specialists

  6. Bio-nano complexes of ZVFeNPs/Fe-s-M13 and Cd (II)/Cd-s-M13 accelerate Cd (II) reduction by FeNPs through dual dispersing and separate deposition (United States)

    Zhang, Shuai; Nakano, Kazuhiko; Yu, Huimin; Shen, Zhongyao


    Reduction of Cd (II) in liquor by solid zero valent Fe nanoparticles (ZVFeNPs) is a liquid-solid biphasic reaction in which the reduction efficiency was often lowered by either aggregation of ZVFeNPs or coating of the generated ZVCd. In light of the filamentous nanostructure of bacteriophage M13 with ˜2700 copies of pVIII protein in delicate distribution at the coat, a novel dual dispersing reduction route was designed by introducing two different kinds of M13 with Fe-binding specificity (Fe-s-M13) and Cd-binding specificity (Cd-s-M13) to disperse ZVFeNPs and Cd (II) ions, respectively. The Fe-s-M13 was used for synthesis of the ZVFeNPs/Fe-s-M13 complex, where ZVFeNPs were uniformly dispersed into small nanoparticles (5-10 nm) on Fe-s-M13. The engineered Cd-s-M13, constructed by genetic recombination of pVIII through inserting the gene of a biopanned 7-mer Cd-specific peptide (SCPICPG) into the N-terminus of pVIII gene, was used for Cd (II) dispersion before reduction. The dispersed complex of Cd(II)/Cd-s-M13 was rapidly reduced by complex of ZVFeNPs/Fe-s-M13. Kinetics results showed that the initial reduction rate and final reduction ratio of Cd (II) increased by 35.7% and 16.4%, respectively, through dispersion of ZVFeNPs by Fe-s-M13; they improved again by 53.6% and 37.0%, respectively, through further dispersion of Cd (II) by Cd-s-M13. TEM and EDS results revealed that the acceleration effect of the dual dispersing reduction was arising from uniform dispersion of the small ZVFeNPs and separate deposition of the reduced ZVCd on the two different M13 phages.

  7. Efficient separations & processing crosscutting program

    Energy Technology Data Exchange (ETDEWEB)



    The Efficient Separations and Processing Crosscutting Program (ESP) was created in 1991 to identify, develop, and perfect chemical and physical separations technologies and chemical processes which treat wastes and address environmental problems throughout the DOE complex. The ESP funds several multiyear tasks that address high-priority waste remediation problems involving high-level, low-level, transuranic, hazardous, and mixed (radioactive and hazardous) wastes. The ESP supports applied research and development (R & D) leading to the demonstration or use of these separations technologies by other organizations within the Department of Energy (DOE), Office of Environmental Management.

  8. Virus separation using membranes. (United States)

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter


    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies).

  9. New insight from noble gas and stable isotopes of geothermal/hydrothermal fluids at Caviahue-Copahue Volcanic Complex: Boiling steam separation and water-rock interaction at shallow depth (United States)

    Roulleau, Emilie; Tardani, Daniele; Sano, Yuji; Takahata, Naoto; Vinet, Nicolas; Bravo, Francisco; Muñoz, Carlos; Sanchez, Juan


    We measured noble gas and stable isotopes of the geothermal and hydrothermal fluids of the Caviahue-Copahue Volcanic Complex (CCVC), one of the most important geothermal systems in Argentina/Chile, in order to provide new insights into fluid circulation and origin. With the exception of Anfiteatro and Chancho-co geothermal systems, mantle-derived helium dominates in the CCVC fluids, with measured 3He/4He ratios up to 7.86Ra in 2015. Their positive δ15N is an evidence for subducted sediment-derived nitrogen, which is commonly observed in subduction settings. Both He-N2-Ar composition and positive correlation between δD-H2O and δ18O-H2O suggest that the fluids from Anfiteatro and Chancho-co (and partly from Pucon-Mahuida as well, on the southern flank of Copahue volcano) represent a meteoric water composition with a minor magmatic contribution. The Ne, Kr and Xe isotopic compositions are entirely of atmospheric origin, but processes of boiling and steam separation have led to fractionation of their elemental abundances. We modeled the CCVC fluid evolution using Rayleigh distillation curves, considering an initial air saturated geothermal water (ASGW) end-member at 250 and 300 °C, followed by boiling and steam separation at lower temperatures (from 200 °C to 150 °C). Between 2014 and 2015, the CCVC hydrogen and oxygen isotopes shifted from local meteoric water-dominated to andesitic water-dominated signature. This shift is associated with an increase of δ13C values and Stotal, HCl and He contents. These characteristics are consistent with a change in the gas ascent pathway between 2014 and 2015, which in turn induced higher magmatic-hydrothermal contribution in the fluid signature. The composition of the magmatic source of the CCVC fluids is: 3He/4He = 7.7Ra, δ15N = + 6‰, and δ13C = - 6.5‰. Mixing models between air-corrected He and N suggest the involvement of 0.5% to 5% of subducted sediments in the magmatic source. The magmatic sulfur isotopic

  10. Printed Spacecraft Separation System

    Energy Technology Data Exchange (ETDEWEB)

    Dehoff, Ryan R [ORNL; Holmans, Walter [Planetary Systems Corporation


    In this project Planetary Systems Corporation proposed utilizing additive manufacturing (3D printing) to manufacture a titanium spacecraft separation system for commercial and US government customers to realize a 90% reduction in the cost and energy. These savings were demonstrated via “printing-in” many of the parts and sub-assemblies into one part, thus greatly reducing the labor associated with design, procurement, assembly and calibration of mechanisms. Planetary Systems Corporation redesigned several of the components of the separation system based on additive manufacturing principles including geometric flexibility and the ability to fabricate complex designs, ability to combine multiple parts of an assembly into a single component, and the ability to optimize design for specific mechanical property targets. Shock absorption was specifically targeted and requirements were established to attenuate damage to the Lightband system from shock of initiation. Planetary Systems Corporation redesigned components based on these requirements and sent the designs to Oak Ridge National Laboratory to be printed. ORNL printed the parts using the Arcam electron beam melting technology based on the desire for the parts to be fabricated from Ti-6Al-4V based on the weight and mechanical performance of the material. A second set of components was fabricated from stainless steel material on the Renishaw laser powder bed technology due to the improved geometric accuracy, surface finish, and wear resistance of the material. Planetary Systems Corporation evaluated these components and determined that 3D printing is potentially a viable method for achieving significant cost and savings metrics.

  11. Fictional Separation Logic

    DEFF Research Database (Denmark)

    Jensen, Jonas Buhrkal; Birkedal, Lars


    , separation means physical separation. In this paper, we introduce \\emph{fictional separation logic}, which includes more general forms of fictional separating conjunctions P * Q, where "*" does not require physical separation, but may also be used in situations where the memory resources described by P and Q...... overlap. We demonstrate, via a range of examples, how fictional separation logic can be used to reason locally and modularly about mutable abstract data types, possibly implemented using sophisticated sharing. Fictional separation logic is defined on top of standard separation logic, and both the meta...

  12. Separating biological cells (United States)

    Brooks, D. E.


    Technique utilizing electric field to promote biological cell separation from suspending medium in zero gravity increases speed, reduces sedimentation, and improves efficiency of separation in normal gravity.

  13. Controlling Separation in Turbomachines (United States)

    Evans, Simon; Himmel, Christoph; Power, Bronwyn; Wakelam, Christian; Xu, Liping; Hynes, Tom; Hodson, Howard


    Four examples of flow control: 1) Passive control of LP turbine blades (Laminar separation control). 2) Aspiration of a conventional axial compressor blade (Turbulent separation control). 3) Compressor blade designed for aspiration (Turbulent separation control). 4.Control of intakes in crosswinds (Turbulent separation control).

  14. Mg2+-modulated KMnO4 reactivity of thymines in the open transcription complex reflects variation in the negative electrostatic potential along the separated DNA strands. Footprinting of Escherichia coli RNA polymerase complex at the lambdaP(R) promoter revisited. (United States)

    Łoziński, Tomasz; Wierzchowski, Kazimierz L


    There is still a controversy over the mechanism of promoter DNA strand separation upon open transcription complex (RPo) formation by Escherichia coli RNA polymerase: is it a single or a stepwise process controlled by Mg2+ ions and temperature? To resolve this question, the kinetics of pseudo-first-order oxidation of thymine residues by KMnO4 in the -11 ... +2 DNA region of RPo at the lambdaP(R) promoter was examined under single-hit conditions as a function of temperature (13-37 degrees C) in the absence or presence of 10 mm MgCl2. The reaction was also studied with respect to thymidine and its nucleotides (TMP, TTP and TpT) as a function of temperature and [MgCl2]. The kinetic parameters, (ox)k and (ox)E(a), and Mg-induced enhancement of (ox)k proved to be of the same order of magnitude for RPo-lambdaP(R) and the nucleotides. Unlike the complex, (ox)E(a) for the nucleotides was found to be Mg-independent. The isothermal increase in (ox)k with increasing [Mg2+] was thus interpreted in terms of a simple model of screening of the negative charges on phosphate groups by Mg2+ ions, lowering the electrostatic barrier to the diffusion of MnO4- anions to the reactive double bond of thymine. Similar screening isotherms were determined for the oxidation of two groups of thymines in RPo at a consensus-like Pa promoter, differing in the magnitude of the Mg effect. Together, the findings show that: (a) the two DNA strands in the -11...+2 region of RPo-lambdaP(R) are completely separated over the whole range of temperatures investigated (13-37 degrees C) in the absence of Mg2+ (b) Mg2+ ions induce an increase in the rate of the oxidation reaction by screening negatively charged phosphate and carboxylate groups; and (c) the observed thymine reactivity and the magnitude of the Mg effect reflect variation in the strength of the electrostatic potential along the separated DNA strands, in agreement with the current structural model of RPo.

  15. Development of Radiochemical Separation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eil Hee; Kim, K. W.; Yang, H. B. (and others)


    This project of the second phase was aimed at the development of basic unit technologies for advanced partitioning, and the application tests of pre-developed partitioning technologies for separation of actinides by using a simulated multi-component radioactive waste containing Am, Np, Tc, U and so on. The goals for recovery yield of TRU, and for purity of Tc are high than 99% and about 99%, respectively. The work scopes and contents were as follows. 1). For the development of basic unit technologies for advanced partitioning. 1. Development of technologies for co-removal of TRU and for mutual separation of U and TRU with a reduction-complexation reaction. 2. Development of extraction system for high-acidity co-separation of An(+3) and Ln(+3) and its radiolytic evaluation. 3. Synthesis of extractants for the selective separation of An(+3) and its relevant extraction system development. 4. Development of a hybrid system for the recovery of noble metals and its continuous separation tests. 5. Development of electrolytic system for the decompositions of N-NO3 and N-NH3 compounds to nitrogen gas. 2). For the application test of pre-developed partitioning technologies for the separation of actinide elements in a simulated multi-component solution equivalent to HLW level. 1. Co-separation of Tc, Np and U by a (TBP-TOA)/NDD system. 2. Mutual-separation of Am, Cm and RE elements by a (Zr-DEHPA)/NDD system. All results will be used as the fundamental data for the development of advanced partitioning process in the future.

  16. Separation of Concerns and Then What?

    DEFF Research Database (Denmark)

    Ernst, Erik


    Separation of concerns by explicit aspectualization is but one tool in a more complex toolbox. In particular, integration of separately expressed aspects must also be considered, and this integration may be so tight that the aspects cannot be expressed fully independently in the rst place. This g...

  17. Magnetic separation of algae (United States)

    Nath, Pulak; Twary, Scott N.


    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  18. Separation anxiety in children (United States)

    ... page: // Separation anxiety in children To use the sharing features on this page, please enable JavaScript. Separation anxiety in children is a developmental stage in which ...

  19. Separators for electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert


    Provided are separators for use in an electrochemical cell comprising (a) an inorganic oxide and (b) an organic polymer, wherein the inorganic oxide comprises organic substituents. Also provided are electrochemical cells comprising such separators.

  20. Meniscus Membranes For Separation (United States)

    Dye, Robert C.; Jorgensen, Betty; Pesiri, David R.


    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  1. Membrane manufacture for peptide separations

    KAUST Repository

    Kim, Dooli


    Nanostructured polymeric membranes are key tools in biomedical applications such as hemodialysis, protein separations, in the food industry, and drinking water supply from seawater. Despite of the success in different separation processes, membrane manufacture itself is at risk, since the most used solvents are about to be banned in many countries due to environmental and health issues. We propose for the first time the preparation of polyethersulfone membranes based on dissolution in the ionic liquid 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM]DEP). We obtained a series of membranes tailored for separation of solutes with molecular weight of 30, 5, 1.3, and 1.25 kg mol-1 with respective water permeances of 140, 65, 30 and 20 Lm-2h-1bar-1. We demonstrate their superior efficiency in the separation of complex mixtures of peptides with molecular weights in the range of 800 to 3500 gmol-1. Furthermore, the thermodynamics and kinetics of phase separation leading to the pore formation in the membranes were investigated. The rheology of the solutions and the morphology of the prepared membranes were examed and compared to those of polyethersulfone in organic solvents currently used for membrane manufacture.

  2. Tableaus and their use in Holomorphic Dynamics

    DEFF Research Database (Denmark)

    Branner, Bodil

    rules, classification of critical tableaus, the Fibonacci critical tableau. TITLE of class III: Points are points. ABSTRACT: Combining the geometrical, analytical and combinatorial parts to conclude either local connectivity of the Julia set of a polynomial in the Yoccoz-class or total disconnectivity...

  3. Multiple point spaces of finite holomorphic maps


    Peñafort Sanchis, Guillermo


    Esta tesis trata sobre espacios múltiples de aplicaciones holomorfas finitas entre variedades complejas. Nuestro enfoque es el de la teoría de singularidades, y las aplicaciones serán consideradas bajo la relación de A-equivalencia, es decir, salvo cambios de coordenadas en partida y llegada. Nos centramos en relacionar propiedades de los espacios de puntos múltiples con propiedades como la A-estabilidad y la A-determinación finita. En generaEl trabajo está organizado de la siguiente manera:...

  4. Safety shutdown separators (United States)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert


    The present invention pertains to electrochemical cells which comprise (a) an anode; (b) a cathode; (c) a solid porous separator, such as a polyolefin, xerogel, or inorganic oxide separator; and (d) a nonaqueous electrolyte, wherein the separator comprises a porous membrane having a microporous coating comprising polymer particles which have not coalesced to form a continuous film. This microporous coating on the separator acts as a safety shutdown layer that rapidly increases the internal resistivity and shuts the cell down upon heating to an elevated temperature, such as C. Also provided are methods for increasing the safety of an electrochemical cell by utilizing such separators with a safety shutdown layer.

  5. Acoustofluidic bacteria separation (United States)

    Li, Sixing; Ma, Fen; Bachman, Hunter; Cameron, Craig E.; Zeng, Xiangqun; Huang, Tony Jun


    Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device for label-free bacterial separation from human blood samples. In particular, we exploit the acoustic radiation force generated from a tilted-angle standing surface acoustic wave (taSSAW) field to separate Escherichia coli from human blood cells based on their size difference. Flow cytometry analysis of the E. coli separated from red blood cells shows a purity of more than 96%. Moreover, the label-free electrochemical detection of the separated E. coli displays reduced non-specific signals due to the removal of blood cells. Our acoustofluidic bacterial separation platform has advantages such as label-free separation, high biocompatibility, flexibility, low cost, miniaturization, automation, and ease of in-line integration. The platform can be incorporated with an on-chip sensor to realize a point-of-care sepsis diagnostic device.

  6. Rapid chemical separations

    CERN Document Server

    Trautmann, N


    A survey is given on the progress of fast chemical separation procedures during the last few years. Fast, discontinuous separation techniques are illustrated by a procedure for niobium. The use of such techniques for the chemical characterization of the heaviest known elements is described. Other rapid separation methods from aqueous solutions are summarized. The application of the high speed liquid chromatography to the separation of chemically similar elements is outlined. The use of the gas jet recoil transport method for nuclear reaction products and its combination with a continuous solvent extraction technique and with a thermochromatographic separation is presented. Different separation methods in the gas phase are briefly discussed and the attachment of a thermochromatographic technique to an on-line mass separator is shown. (45 refs).

  7. Magnetic separation for environmental remediation

    Energy Technology Data Exchange (ETDEWEB)

    Schake, A.R.; Avens, L.R.; Hill, D.D.; Padilla, D.D.; Prenger, F.C.; Romero, D.A.; Worl, L.A. [Los Alamos National Lab., NM (United States); Tolt, T.L. [Lockheed Environmental Systems and Technologies Co., Las Vegas, NV (United States)


    High Gradient Magnetic Separation (HGMS) is a form of magnetic separation used to separate solids from other solids, liquids or gases. HGMS uses large magnetic field gradients to separate ferromagnetic and paramagnetic particles from diamagnetic host materials. The technology relies only on physical properties, and therefore separations can be achieved while producing a minimum of secondary waste. Actinide and fission product wastes within the DOE weapons complex pose challenging problems for environmental remediation. Because the majority of actinide complexes and many fission products are paramagnetic, while most host materials are diamagnetic, HGMS can be used to concentrate the contaminants into a low volume waste stream. The authors are currently developing HGMS for applications to soil decontamination, liquid waste treatment, underground storage tank waste treatment, and actinide chemical processing residue concentration. Application of HGMS usually involves passing a slurry of the contaminated mixture through a magnetized volume. Field gradients are produced in the magnetized volume by a ferromagnetic matrix material, such as steel wool, expanded metal, iron shot, or nickel foam. The matrix fibers become trapping sites for ferromagnetic and paramagnetic particles in the host material. The particles with a positive susceptibility are attracted toward an increasing magnetic field gradient and can be extracted from diamagnetic particles, which react in the opposite direction, moving away from the areas of high field gradients. The extracted paramagnetic contaminants are flushed from the matrix fibers when the magnetic field is reduced to zero or when the matrix canister is removed from the magnetic field. Results are discussed for the removal of uranium trioxide from water, PuO{sub 2}, U, and Pu from various soils (Fernald, Nevada Test Site), and the waste water treatment of Pu and Am isotopes using HGMS.

  8. Flow injection and sequential injection: The optimal solutions for executing appropriate on-line separation and preconcentration schemes for detection of trace-level concentrations of metals in complex matrices by ICPMS

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    , or because the analyte material, in addition to suitable separations, needs to be subjected to preconcentration. Such pretreatments schemes are advantageously performed in flow injection (FI) or sequential injection (SI) manifolds, where all unit operations can be effected on-line and under enclosed...... and strictly controlled conditions. Various separation/preconcentration procedures are feasible, such as liquid-liquid extraction encompassing back-extraction into an aqueous solution, (co)precipitation with collection in knotted reactors, adsorption on columns packed with hydrophophilic or hydrophobic...... as these adversely will impair its performance. In the lecture, selected examples of separation/preconcentration FI/SI-procedures for the determination of trace levels of metals will be presented, particular emphasis being placed on the use of the novel “lab-on-valve” (LOV) concept....

  9. Compactifications of heterotic theory on non-Kaehler complex manifolds, I

    CERN Document Server

    Becker, K; Das-Gupta, K; Green, P S


    We study new compactifications of the SO(32) heterotic string theory on compact complex non-Kaehler manifolds. These manifolds have many interesting features like fewer moduli, torsional constraints, vanishing Euler character and vanishing first Chern class, which make the four-dimensional theory phenomenologically attractive. We take a particular compact example studied earlier and determine various geometrical properties of it. In particular we calculate the warp factor and study the sigma model description of strings propagating on these backgrounds. The anomaly cancellation condition and enhanced gauge symmetry are shown to arise naturally in this framework, if one considers the effect of singularities carefully. We then give a detailed mathematical analysis of these manifolds and construct a large class of them. The existence of a holomorphic (3,0) form is important for the construction. We clarify some of the topological properties of these manifolds and evaluate the Betti numbers. We also determine the...

  10. The ADvanced SEParation (ADSEP) (United States)


    The ADvanced SEParation (ADSEP) commercial payload is making use of major advances in separation technology: The Phase Partitioning Experiment (PPE); the Micorencapsulation experiment; and the Hemoglobin Separation Experiment (HSE). Using ADSEP, commercial researchers will attempt to determine the partition coefficients for model particles in a two-phase system. With this information, researchers can develop a higher resolution, more effective cell isolation procedure that can be used for many different types of research and for improved health care. The advanced separation technology is already being made available for use in ground-based laboratories.

  11. Separation of flow

    CERN Document Server

    Chang, Paul K


    Interdisciplinary and Advanced Topics in Science and Engineering, Volume 3: Separation of Flow presents the problem of the separation of fluid flow. This book provides information covering the fields of basic physical processes, analyses, and experiments concerning flow separation.Organized into 12 chapters, this volume begins with an overview of the flow separation on the body surface as discusses in various classical examples. This text then examines the analytical and experimental results of the laminar boundary layer of steady, two-dimensional flows in the subsonic speed range. Other chapt

  12. A strong steric hindrance effect on ground state, excited state, and charge separated state properties of a CuI-diimine complex captured by X-ray transient absorption spectroscopy

    DEFF Research Database (Denmark)

    Huang, J.; Mara, M.W.; Stickrath, A.B.


    Photophysical and structural properties of a CuI diimine complex with very strong steric hindrance, [CuI(dppS)2]+ (dppS = 2,9-diphenyl-1,10-phenanthroline disulfonic acid disodium salt), are investigated by optical and X-ray transient absorption (OTA and XTA) spectroscopy. The bulky phenylsulfoni...... of metal complex/semiconductor NP hybrids but also provide guidance for designing efficient CuI diimine complexes with optimized structures for application in solar-to-electricity conversion. This journal is...

  13. Nonterminal Separating Macro Grammars

    NARCIS (Netherlands)

    Hogendorp, Jan Anne


    We extend the concept of nonterminal separating (or NTS) context-free grammar to nonterminal separating $m$-macro grammar where the mode of derivation $m$ is equal to "unrestricted". "outside-in' or "inside-out". Then we show some (partial) characterization results for these NTS $m$-macro grammars.

  14. Working with Separation (United States)

    Krugman, Dorothy C.


    Discusses the role of the caseworker in providing support to children experiencing separation from their families and emphasizes the need to recognize that there are differences between those separation experiences dictated by the needs of children and those dictated by arbitrary or noncasework factors. (AJ)

  15. Separation anxiety disorder

    NARCIS (Netherlands)

    Nauta, M.H.; Emmelkamp, P.M.G.; Sturmey, P.; Hersen, M.


    Separation anxiety disorder (SAD) is the only anxiety disorder that is specific to childhood; however, SAD has hardly ever been addressed as a separate disorder in clinical trials investigating treatment outcome. So far, only parent training has been developed specifically for SAD. This particular

  16. Social Separation in Monkeys. (United States)

    Mineka, Susan; Suomi, Stephen J.


    Reviews phenomena associated with social separation from attachment objects in nonhuman primates. Evaluates four theoretical treatments of separation in light of existing data: Bowlby's attachment-object-loss theory, Kaufman's conservation-withdrawal theory, Seligman's learned helplessness theory, and Solomon and Corbit's opponent-process theory.…

  17. Complex chemistry with complex compounds

    Directory of Open Access Journals (Sweden)

    Eichler Robert


    Full Text Available In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the investigation of fragile single molecular species by gas-phase chromatography. The latest success with the heaviest group 6 transactinide seaborgium is highlighted. The formation of a very volatile hexacarbonyl compound Sg(CO6 was observed similarly to its lighter homologues molybdenum and tungsten. The interactions of these gaseous carbonyl complex compounds with quartz surfaces were investigated by thermochromatography. Second-generation experiments are under way to investigate the intramolecular bond between the central metal atom of the complexes and the ligands addressing the influence of relativistic effects in the heaviest compounds. Our contribution comprises some aspects of the ongoing challenging experiments as well as an outlook towards other interesting compounds related to volatile complex compounds in the gas phase.

  18. Complexation of trivalent actinides and lanthanides with hydrophilic N-donor ligands for Am(III)/Cm(III) and An(III)/Ln(III) separation; Komplexierung von trivalenten Actiniden und Lanthaniden mit hydrophilen N-Donorliganden zur Am(III)/Cm(III)- bzw. An(III)/Ln(III)-Trennung

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Christoph


    The implementation of actinide recycling processes is considered in several countries, aiming at the reduction of long-term radiotoxicity and heat load of used nuclear fuel. This requires the separation of the actinides from the fission and corrosion products. The separation of the trivalent actinides (An(III)) Am(III) and Cm(III), however, is complicated by the presence of the chemically similar fission lanthanides (Ln(III)). Hydrophilic N-donor ligands are employed as An(III) or Am(III) selective complexing agents in solvent extraction to strip An(III) or Am(III) from an organic phase loaded with An(III) and Ln(III). Though they exhibit excellent selectivity, the complexation chemistry of these ligands and the complexes formed during solvent extraction are not sufficiently characterized. In the present thesis the complexation of An(III) and Ln(III) with hydrophilic N-donor ligands is studied by time resolved laser fluorescence spectroscopy (TRLFS), UV/Vis, vibronic sideband spectroscopy and solvent extraction. TRLFS studies on the complexation of Cm(III) and Eu(III) with the Am(III) selective complexing agent SO{sub 3}-Ph-BTBP (tetrasodium 3,3{sup '},3'',3{sup '''}-([2,2{sup '}-bipyridine]-6,6{sup '}-diylbis(1,2,4-triazine-3,5,6-triyl)) tetrabenzenesulfonate) revealed the formation of [M(SO{sub 3}-Ph-BTBP){sub n}]{sup (4n-3)-} complexes (M = Cm(III), Eu(III); n = 1, 2). The conditional stability constants were determined in different media yielding two orders of magnitude larger β{sub 2}-values for the Cm(III) complexes, independently from the applied medium. A strong impact of ionic strength on the stability and stoichiometry of the formed complexes was identified, resulting from the stabilization of the pentaanionic [M(SO{sub 3}-Ph-BTBP){sub 2}]{sup 5-} complex with increasing ionic strength. Thermodynamic studies of Cm(III)-SO{sub 3}-Ph-BTBP complexation showed that the proton concentration of the applied medium impacts

  19. Enhanced separation of rare earth elements

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Herbst, R. S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Welty, A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Soderstrom, M. D. [Cytec Solvay Group, Tempe, AZ (United States); Jakovljevic, B. [Cytec Solvay Group, Niagara Falls, ON (Canada)


    Industrial rare earth separation processes utilize PC88A, a phosphonic acid ligand, for solvent extraction separations. The separation factors of the individual rare earths, the equipment requirements, and chemical usage for these flowsheets are well characterized. Alternative ligands such as Cyanex® 572 and the associated flowsheets are being investigated at the pilot scale level to determine if significant improvements to the current separation processes can be realized. These improvements are identified as higher separation factors, reduced stage requirements, or reduced chemical consumption. Any of these improvements can significantly affect the costs associated with these challenging separation proccesses. A mid/heavy rare earth element (REE) separations flowsheet was developed and tested for each ligand in a 30 stage mixer-settler circuit to compare the separation performance of PC88A and Cyanex® 572. The ligand-metal complex strength of Cyanex® 572 provides efficient extraction of REE while significantly reducing the strip acid requirements. Reductions in chemical consumption have a significant impact on process economics for REE separations. Partitioning results summarized Table 1 indicate that Cyanex® 572 offers the same separation performance as PC88A while reducing acid consumption by 30% in the strip section for the mid/heavy REE separation. Flowsheet Effluent Compositions PC88A Cyanex® 572 Raffinate Mid REE Heavy REE 99.40% 0.60% 99.40% 0.60% Rich Mid REE Heavy REE 2.20% 97.80% 0.80% 99.20% Liquor Strip Acid Required 3.4 M 2.3 M Table 1 – Flowsheet results comparing separation performance of PC88A and Cyanex® 572 for a mid/heavy REE separation.

  20. Chromatographic hydrogen isotope separation (United States)

    Aldridge, Frederick T.


    Intermetallic compounds with the CaCu.sub.5 type of crystal structure, particularly LaNiCo.sub.4 and CaNi.sub.5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors.

  1. Rotary drum separator system (United States)

    Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)


    A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.

  2. Radiochemical separation of Cobalt

    NARCIS (Netherlands)

    Erkelens, P.C. van


    A method is described for the radiochemical separation of cobalt based on the extraordinary stability of cobalt diethyldithiocarbamate. Interferences are few; only very small amounts of zinc and iron accompany cobalt, which is important in neutron-activation analysis.

  3. Separation Anxiety (For Parents) (United States)

    ... older child, there might be another problem, like bullying or abuse. Separation anxiety is different from the normal feelings older kids have when they don't want a parent to leave (which can usually be overcome if ...

  4. Separation by solvent extraction (United States)

    Holt, Jr., Charles H.


    17. A process for separating fission product values from uranium and plutonium values contained in an aqueous solution, comprising adding an oxidizing agent to said solution to secure uranium and plutonium in their hexavalent state; contacting said aqueous solution with a substantially water-immiscible organic solvent while agitating and maintaining the temperature at from to C. until the major part of the water present is frozen; continuously separating a solid ice phase as it is formed; separating a remaining aqueous liquid phase containing fission product values and a solvent phase containing plutonium and uranium values from each other; melting at least the last obtained part of said ice phase and adding it to said separated liquid phase; and treating the resulting liquid with a new supply of solvent whereby it is practically depleted of uranium and plutonium.

  5. Separable Arrowhead Microneedles (United States)

    Chu, Leonard Y.; Prausnitz, Mark R.


    Hypodermic needles cause pain and bleeding, produce biohazardous sharp waste and require trained personnel. To address these issues, we introduce separable arrowhead microneedles that rapidly and painlessly deliver drugs and vaccines to the skin. These needles are featured by micron-size sharp tips mounted on blunt shafts. Upon insertion in the skin, the sharp-tipped polymer arrowheads encapsulating drug separate from their metal shafts and remain embedded in the skin for subsequent dissolution and drug release. The blunt metal shafts can then be discarded. Due to rapid separation of the arrowhead tips from the shafts within seconds, administration using arrowhead microneedles can be carried out rapidly, while drug release kinetics can be independently controlled based on separable arrowhead formulation. Thus, drug and vaccine delivery using arrowhead microneedles are designed to offer a quick, convenient, safe and potentially self-administered method of drug delivery as an alternative to hypodermic needles. PMID:21047538

  6. Hydrogen separation process (United States)

    Mundschau, Michael [Longmont, CO; Xie, Xiaobing [Foster City, CA; Evenson, IV, Carl; Grimmer, Paul [Longmont, CO; Wright, Harold [Longmont, CO


    A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

  7. Binodal Compositions of Polyelectrolyte Complexes

    NARCIS (Netherlands)

    Spruijt, E.; Westphal, A.H.; Borst, J.W.; Cohen Stuart, M.A.; Gucht, van der J.


    When oppositely charged polyelectrolytes are mixed below a critical salt concentration, their mixtures show macroscopic phase separation into a dilute and a dense, polyelectrolyte complex phase. Binodal compositions of the polyelectrolyte complexes have been measured experimentally using

  8. Gulf stream separation dynamics (United States)

    Schoonover, Joseph

    Climate models currently struggle with the more traditional, coarse ( O(100 km) ) representation of the ocean. In these coarse ocean simulations, western boundary currents are notoriously difficult to model accurately. The modeled Gulf Stream is typically seen exhibiting a mean pathway that is north of observations, and is linked to a warm sea-surface temperature bias in the Mid-Atlantic Bight. Although increased resolution ( O(10 km) ) improves the modeled Gulf Stream position, there is no clean recipe for obtaining the proper pathway. The 70 year history of literature on the Gulf Stream separation suggests that we have not reached a resolution on the dynamics that control the current's pathway just south of the Mid-Atlantic Bight. Without a concrete knowledge on the separation dynamics, we cannot provide a clean recipe for accurately modeling the Gulf Stream at increased resolutions. Further, any reliable parameterization that yields a realistic Gulf Stream path must express the proper physics of separation. The goal of this dissertation is to determine what controls the Gulf Stream separation. To do so, we examine the results of a model intercomparison study and a set of numerical regional terraforming experiments. It is argued that the separation is governed by local dynamics that are most sensitive to the steepening of the continental shelf, consistent with the topographic wave arrest hypothesis of Stern (1998). A linear extension of Stern's theory is provided, which illustrates that wave arrest is possible for a continuously stratified fluid.

  9. Employment of methyl 2-pyridyl ketone oxime in 3d/4f-metal chemistry: dinuclear nickel(II)/lanthanide(III) species and complexes containing the metals in separate ions. (United States)

    Polyzou, Christina D; Nikolaou, Helen; Papatriantafyllopoulou, Constantina; Psycharis, Vassilis; Terzis, Aris; Raptopoulou, Catherine P; Escuer, Albert; Perlepes, Spyros P


    The use of methyl 2-pyridyl ketone oxime (mpkoH) for the synthesis of Ni(II)/Ln(III) (Ln = lanthanide) complexes, using "one-pot" reactions in the absence of an external base, is described. Depending on the reaction and crystallization conditions employed, two families of complexes have been obtained. The first family consists of true heterometallic species and involves complexes [NiLn(mpko)(3)(mpkoH)(3)](ClO(4))(2), where Ln = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er. The second family contains the pseudo heterometallic complexes [Ni(mpkoH)(3)](2)[Ln(NO(3))(6)](ClO(4)), where Ln = La, Ce, Pr, Nd and Sm. The crystal structures of [NiCe(mpko)(3)(mpkoH)(3)](ClO(4))(2) (1), [NiDy(mpko)(3)(mpkoH)(3)](ClO(4))(2) (8) and [Ni(mpkoH)(3)](2)[La(NO(3))(6)](ClO(4)) (11) have been determined by single-crystal, X-ray crystallography. Complexes 1·1.2MeOH·0.6H(2)O and 8·1.2MeOH·0.6H(2)O crystallise in the monoclinic space group P2(1)/a and are isomorphous; there are two crystallographically independent cations in the unit cell, but their interatomic distances and angles differ little. The Ni(II) and Ln(III) ions are bridged by three oximate groups belonging to the η(1):η(1):η(1):μ mpko(-) ligands. The Ni(II) centre is octahedrally coordinated by the six nitrogen atoms of the mpko(-) ligands in a facial arrangement. The Ln(III) centre is bound to an (O(oximate))(3)N(6) set of donor atoms, the nitrogen atoms belonging to the three N,N'-bidentate chelating mpkoH ligands. The stereochemistry of the Ln(III) atoms has been evaluated by means of continuous shape measures (CShM). The two crystallographically independent Ce(III) atoms in 1 have tricapped trigonal prismatic and capped square antiprismatic coordination geometries, while the polyhedra of the Dy(III) atoms in 8 are both close to a tricapped trigonal prism. The octahedral Ni(II) atoms in 11 are both facially bound to a N(6) set of donor atoms from three N,N'-bidentate chelating mpkoH ligands, while the 12-coordinate

  10. Mass Separation by Metamaterials (United States)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin


    Being able to manipulate mass flow is critically important in a variety of physical processes in chemical and biomolecular science. For example, separation and catalytic systems, which requires precise control of mass diffusion, are crucial in the manufacturing of chemicals, crystal growth of semiconductors, waste recovery of biological solutes or chemicals, and production of artificial kidneys. Coordinate transformations and metamaterials are powerful methods to achieve precise manipulation of molecular diffusion. Here, we introduce a novel approach to obtain mass separation based on metamaterials that can sort chemical and biomolecular species by cloaking one compound while concentrating the other. A design strategy to realize such metamaterial using homogeneous isotropic materials is proposed. We present a practical case where a mixture of oxygen and nitrogen is manipulated using a metamaterial that cloaks nitrogen and concentrates oxygen. This work lays the foundation for molecular mass separation in biophysical and chemical systems through metamaterial devices.

  11. Unity Through Separation

    DEFF Research Database (Denmark)

    Dabelsteen, Hans B.

    This PhD thesis asks how we can conceptualize the current separation doctrine of religion and politics in a country like Denmark, where the structure of the established church and peoplehood overlap. In order to answer this question, Hans Bruun Dabelsteen maps the current discussion of secularism...... into the principle of treating everybody equally (with religious freedom, equality and Danish peoplehood as the most important principles adjacent to secularism). In a study of the historical roots of the separation doctrine and two current policy cases (same-sex marriage and reforms of church governance...

  12. Gas separation membranes (United States)

    Schell, William J.


    A dry, fabric supported, polymeric gas separation membrane, such as cellulose acetate, is prepared by casting a solution of the polymer onto a shrinkable fabric preferably formed of synthetic polymers such as polyester or polyamide filaments before washing, stretching or calendering (so called griege goods). The supported membrane is then subjected to gelling, annealing, and drying by solvent exchange. During the processing steps, both the fabric support and the membrane shrink a preselected, controlled amount which prevents curling, wrinkling or cracking of the membrane in flat form or when spirally wound into a gas separation element.

  13. Separation membrane development

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.W. [Savannah River Technology Center, Aiken, SC (United States)


    A ceramic membrane has been developed to separate hydrogen from other gases. The method used is a sol-gel process. A thin layer of dense ceramic material is coated on a coarse ceramic filter substrate. The pore size distribution in the thin layer is controlled by a densification of the coating materials by heat treatment. The membrane has been tested by permeation measurement of the hydrogen and other gases. Selectivity of the membrane has been achieved to separate hydrogen from carbon monoxide. The permeation rate of hydrogen through the ceramic membrane was about 20 times larger than Pd-Ag membrane.

  14. Spiral Flow Separator (United States)

    Robertson, Glen A.


    Proposed liquid-separating device relies on centrifugal force in liquid/liquid or liquid/solid mixture in spiral path. Operates in continuous flow at relatively high rates. Spiral tubes joined in sequence, with outlet tubes connected to joints. Cross-sectional areas of successive spiral tubes decreases by cross-sectional areas of outlet tubes. Centrifugal force pushes denser particles or liquids to outer edge of spiral, where removed from flow. Principle exploited to separate solids from wastewater, oil from fresh or salt water, or contaminants from salt water before evaporation. Also used to extract such valuable materials as precious metals from slurries.

  15. Separation techniques: Chromatography (United States)

    Coskun, Ozlem


    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorption, partition, and size exclusion. Other chromatography techniques are based on the stationary bed, including column, thin layer, and paper chromatography. Column chromatography is one of the most common methods of protein purification. PMID:28058406

  16. diffusive phase separation

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kenmochi


    w is constrained to have double obstacles σ*≤w≤σ* (i.e., σ* and σ* are the threshold values of w. The objective of this paper is to discuss the semigroup {S(t} associated with the phase separation model, and construct its global attractor.

  17. Fathering After Marital Separation (United States)

    Keshet, Harry Finkelstein; Rosenthal, Kristine M.


    Deals with experiences of a group of separated or divorced fathers who chose to remain fully involved in the upbringing of their children. As they underwent transition from married parenthood to single fatherhood, these men learned that meeting demands of child care contributed to personal stability and growth. (Author)

  18. Separation of Concerns

    DEFF Research Database (Denmark)

    Ernst, Erik


    Separation of concerns is a crucial concept in discussions about software engineering consequences of programming language design decisions, especially in AOSD. This paper proposes a way to formalize this concept, and argues that the given formalization is useful even if it is used primarily...


    African Journals Online (AJOL)

    B. S. Chandravanshi

    The developed coprecipitation procedure has been applied to road dust, anodic slime, industrial electronic waste materials and water samples to determine their Pd(II) levels. KEY WORDS: Palladium, Separation, Preconcentration, Carrier element free coprecipitation. INTRODUCTION. Palladium, a precious metal, is widely ...

  20. Polymide gas separation membranes (United States)

    Ding, Yong; Bikson, Benjamin; Nelson, Joyce Katz


    Soluble polyamic acid salt (PAAS) precursors comprised of tertiary and quaternary amines, ammonium cations, sulfonium cations, or phosphonium cations, are prepared and fabricated into membranes that are subsequently imidized and converted into rigid-rod polyimide articles, such as membranes with desirable gas separation properties. A method of enhancing solubility of PAAS polymers in alcohols is also disclosed.

  1. In Situ Synthesis of γ-AlOOH and Synchronous Adsorption Separation of V(V) from Highly Concentrated Cr(VI) Multiplex Complex solutions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hailin [National; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District,; Li, Ping [National; Wang, Zheming [Physcial; Zhang, Xin [Physcial; Zheng, Shili [National; Zhang, Yi [National


    Boehmite (γ-AlOOH) was synthesized to selectively adsorb V(V) from K2CrO4-KVO3-H2O solutions with highly concentrated Cr(VI) and low concentration V(V). The synthesized γ-AlOOH has a BET surface area of 433.2 m2/g and an average pore size of 3.5 nm. It possesses a maximum adsorption capacity of V(V) of 1.53 mmol/g from K2CrO4-KVO3-H2O solutions. The adsorption of V(V) onto γ-AlOOH follows the Langmuir isotherm model and pseudo-second-order kinetics equation by forming innersphere complexes while the Cr(VI) adsorption forms both inner-sphere and outer-sphere chromate complexes depending on solution pH. The γ-AlOOH was further synthesized in situ by adding HNO3 into the K2CrO4-KAlO2- KVO3-H2O solutions and then used for synchronous adsorption of V(V) and Cr(VI), resulting in increased adsorption capacity of V(V) of 2.88 mmol/g and decreased adsorption capacity of Cr(VI) to 0.073 mmol/g, respectively. In the latter process, adsorption pH values were adjustable, and adsorption reached equilibrium instantaneously, supporting a novel in situ synthesis and adsorption integration strategy with adjustable surface charge of adsorbent and disappearance of diffusion effect.

  2. Tooth separation potential problems. (United States)

    Vishwanath, A E; Sharmada, B K; Pai, Sandesh S; Nandini, Nelvigi; Roopa, Tubaki


    A displaced orthodontic elastic separator was proposed as being the source of a gingival abscess that progresses to severe bone loss and exfoliation in a healthy adolescent patient with sound periodontal status prior to commencement of orthodontic treatment. After one year of undergoing orthodontic treatment, the patient presented with dull pain and mobility in the left upper permanent molar for which there was no apparent etiology. On clinical examination the patient had gingival inflammation, associated with a deep pocket and severe mobility (Grade III) in relation to the same teeth. Radiographic examination ofan Orthopantomogram (OPG) and IntraOral Periapical Radiograph (IOPAR) revealed a chronic periodontal abscess with severe necrosis of the periodontal ligament and severe alveolar bone loss. On curettage it was found that there was orthodontic elastic separator which was displaced sub gingivally. Active orthodontic forces were temporarily removed and splinting was done. 6 month follow up showed no mobility and significant improvement of alveolar bone height.

  3. HRS Separator HD

    CERN Multimedia


    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  4. Separation of Climate Signals

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, C; Fodor, I


    Understanding changes in global climate is a challenging scientific problem. Simulated and observed data include signals from many sources, and untangling their respective effects is difficult. In order to make meaningful comparisons between different models, and to understand human effects on global climate, we need to isolate the effects of different sources. Recent eruptions of the El Chichon and Mt. Pinatubo volcanoes coincided with large El Nino and Southern Oscillation (ENSO) events, which complicates the separation of their contributions on global temperatures. Current approaches for separating volcano and ENSO signals in global mean data involve parametric models and iterative techniques [3]. We investigate alternative methods based on principal component analysis (PCA) [2] and independent component analysis (ICA) [1]. Our goal is to determine if such techniques can automatically identify the signals corresponding to the different sources, without relying on parametric models.

  5. Nylon separators. [thermal degradation (United States)

    Lim, H. S.


    A nylon separator was placed in a flooded condition in K0H solution and heated at various high temperatures ranging from 60 C to 110 C. The weight decrease was measured and the molecular weight and decomposition product were analyzed to determine: (1) the effect of K0H concentration on the hydrolysis rate; (2) the effect of K0H concentration on nylon degradation; (3) the activation energy at different K0H concentrations; and (4) the effect of oxygen on nylon degradation. The nylon hydrolysis rate is shown to increase as K0H concentration is decreased 34%, giving a maximum rate at about 16%. Separator hydrolysis is confirmed by molecular weight decrease in age of the batteries, and the reaction of nylon with molecular oxygen is probably negligible, compared to hydrolysis. The extrapolated rate value from the high temperature experiment correlates well with experimental values at 35 degrees.

  6. GPS Separator HD

    CERN Multimedia


    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  7. Medical Separation Among Careerists (United States)


    within their MOS to augment to the career fleet. These selection rates could drop as low as 10% (Lamothe, 2009). Starting in 2009, the program ...regressions, he found that women were 20% more likely to attrite during the Delayed Entry Program , 34% more likely to attrite during Basic Combat Training...such as sexism and tokenism, but these were not specifically applied to separations. 3. Women Serving in Combat Would Strengthen America’s

  8. Innovative Separations Technologies

    Energy Technology Data Exchange (ETDEWEB)

    J. Tripp; N. Soelberg; R. Wigeland


    Reprocessing used nuclear fuel (UNF) is a multi-faceted problem involving chemistry, material properties, and engineering. Technology options are available to meet a variety of processing goals. A decision about which reprocessing method is best depends significantly on the process attributes considered to be a priority. New methods of reprocessing that could provide advantages over the aqueous Plutonium Uranium Reduction Extraction (PUREX) and Uranium Extraction + (UREX+) processes, electrochemical, and other approaches are under investigation in the Fuel Cycle Research and Development (FCR&D) Separations Campaign. In an attempt to develop a revolutionary approach to UNF recycle that may have more favorable characteristics than existing technologies, five innovative separations projects have been initiated. These include: (1) Nitrogen Trifluoride for UNF Processing; (2) Reactive Fluoride Gas (SF6) for UNF Processing; (3) Dry Head-end Nitration Processing; (4) Chlorination Processing of UNF; and (5) Enhanced Oxidation/Chlorination Processing of UNF. This report provides a description of the proposed processes, explores how they fit into the Modified Open Cycle (MOC) and Full Recycle (FR) fuel cycles, and identifies performance differences when compared to 'reference' advanced aqueous and fluoride volatility separations cases. To be able to highlight the key changes to the reference case, general background on advanced aqueous solvent extraction, advanced oxidative processes (e.g., volumetric oxidation, or 'voloxidation,' which is high temperature reaction of oxide UNF with oxygen, or modified using other oxidizing and reducing gases), and fluorination and chlorination processes is provided.

  9. Colour Separation and Aversion

    Directory of Open Access Journals (Sweden)

    Sarah M Haigh


    Full Text Available Aversion to achromatic patterns is well documented but relatively little is known about discomfort from chromatic patterns. Large colour differences are uncommon in the natural environment and deviation from natural statistics makes images uncomfortable (Fernandez and Wilkins 2008, Perception, 37(7, 1098–113; Juricevic et al 2010, Perception, 39(7, 884–899. We report twelve studies documenting a linear increase in aversion to chromatic square-wave gratings as a function of the separation in UCS chromaticity between the component bars, independent of their luminance contrast. Two possible explanations for the aversion were investigated: (1 accommodative response, or (2 cortical metabolic demand. We found no correlation between chromaticity separation and accommodative lag or variance in lag, measured using an open-field autorefractor. However, near infrared spectroscopy of the occipital cortex revealed a larger oxyhaemoglobin response to patterns with large chromaticity separation. The aversion may be cortical in origin and does not appear to be due to accommodation.

  10. The Investigation of Separability of Particles Smaller Than 5 mm by Eddy Current Separation Technology. Part I : Rotating Type Eddy Current Separators

    NARCIS (Netherlands)

    Zhang, S.; Rem, P.C.; Forssberg, E.


    Owing to the growing emergence of the end-of-life electrical and electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal

  11. Glycosaminoglycan blotting and detection after electrophoresis separation. (United States)

    Volpi, Nicola; Maccari, Francesca


    Separation of glycosaminoglycans (GAGs) by electrophoresis and their characterization to the microgram level are integral parts of biochemical research. Their blotting on membranes after electrophoresis offers the advantage to perform further analysis on single separated species such as identification with antibodies and/or recovery of single band. A method for the blotting and immobilizing of several nonsulfated and sulfated complex GAGs on membranes made hydrophilic and positively charged by cationic detergent after their separation by conventional agarose-gel electrophoresis is illustrated. This approach to the study of these complex macromolecules utilizes the capacity of agarose-gel electrophoresis to separate single species of polysaccharides from mixtures and the membrane technology for further preparative and analytical uses. Nitrocellulose membranes are derivatized with the cationic detergent cetylpyridinium chloride (CPC) and mixtures of GAGs are capillary blotted after their separation in agarose-gel electrophoresis. Single purified species of variously sulfated polysaccharides are transferred on derivatized membranes with an efficiency of 100 % and stained with alcian blue (irreversible staining) and toluidine blue (reversible staining). This enables a lower amount limit of detection of 0.1 μg. Nonsulfated polyanions, for example hyaluronic acid (HA), may also be transferred to membranes with a limit of detection of approximately 0.1-0.5 μg after irreversible or reversible staining. The membranes may be stained with reversible staining and the same lanes used for immunological detection or other applications.


    Wilhelm, H.A.; Foos, R.A.


    The usual method for the separation of tantalum and niobium consists of a selective solvent extraction from an aqueous hydrofluoric acid solution of the metals. A difficulty encountered in this process is the fact that the corrosion problems associated with hydrofluoric acid are serious. It has been found that the corrosion caused by the hydrofluoric acid may be substantially reduced by adding to the acidic solution an amine, such as phenyl diethanolamine or aniline, and adjusting pH value to between 4 and 6.


    Maddock, A.G.; Smith, F.


    A method is described for separating plutonium from uranium and fission products by treating a nitrate solution of fission products, uranium, and hexavalent plutonium with a relatively water-insoluble fluoride to adsorb fission products on the fluoride, treating the residual solution with a reducing agent for plutonium to reduce its valence to four and less, treating the reduced plutonium solution with a relatively insoluble fluoride to adsorb the plutonium on the fluoride, removing the solution, and subsequently treating the fluoride with its adsorbed plutonium with a concentrated aqueous solution of at least one of a group consisting of aluminum nitrate, ferric nitrate, and manganous nitrate to remove the plutonium from the fluoride.

  14. Advances in microscale separations towards nanoproteomics applications

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Lian; Piehowski, Paul D.; Shi, Tujin; Smith, Richard D.; Qian, Wei-Jun


    Microscale separations (e.g., liquid chromatography or capillary electrophoresis) coupled with mass spectrometry (MS) has become the primary tool for advanced proteomics, an indispensable technology for gaining understanding of complex biological processes. While significant advances have been achieved in MS-based proteomics, the current platforms still face a significant challenge in overall sensitivity towards nanoproteomics (i.e., with less than 1 g total amount of proteins available) applications such as cellular heterogeneity in tissue pathologies. Herein, we review recent advances in microscale separation techniques and integrated sample processing systems that improve the overall sensitivity and coverage of the proteomics workflow, and their contributions towards nanoproteomics applications.

  15. A Core Language for Separate Variability Modeling

    DEFF Research Database (Denmark)

    Iosif-Lazăr, Alexandru Florin; Wasowski, Andrzej; Schaefer, Ina


    models. Our language, Featherweight VML, has several distinctive features. Its architecture and operations are inspired by the recently proposed Common Variability Language (CVL). Its semantics is considerably simpler than that of CVL, while remaining confluent (unlike CVL). We simplify complex......Separate variability modeling adds variability to a modeling language without requiring modifications of the language or the supporting tools. We define a core language for separate variability modeling using a single kind of variation point to define transformations of software artifacts in object......, this is the first attempt to comprehensively formalize variant derivation, encompassing feature models, variation points, implementation artifacts and transformations....

  16. FY 1999 report on the results of the contract project 'The model project for facilities for effective utilization of industrial waste at the industrial complex in Thailand.' Separate Volume 4 - FY 1999 project; 1999 nendo seika hokokusho. Tai ni okeru kogyo danchi sangyo haikibutsu yuko riyo setsubi moderu jigyo - 4

    Energy Technology Data Exchange (ETDEWEB)



    For the purpose of reducing the consumption of fossil fuel by recycling industrial waste for effective use as petroleum substituting energy in Thailand where the amount of industrial waste is expected to increase, a model project on facilities for effective use of industrial waste at the industrial complex was carried out, and the FY 1999 results were reported. Concretely, the industrial waste generated from each plant at the industrial complex owned by IEAT is to be incinerated in fluidized bed incinerator, and the process steam is to be generated by recovering waste heat by waste heat recovery boiler and to be supplied to plants within the complex. In this fiscal year, the first year of the project, the attachment to the agreement was prepared in terms of the allotment of the project work between Japan and Thailand, various kinds of gist, schedules, etc. and signed. After that, the following were conducted at the Japan side according to the attachment to the agreement: determination of the basic specifications for facilities, basic design, detailed design, manufacture of a part of the equipment, etc. Separate Volume 4 included the results of the inspection of the tank, pump, blower, etc. (NEDO)

  17. Physical Separation in the Workplace

    DEFF Research Database (Denmark)

    Stea, Diego; Foss, Nicolai Juul; Holdt Christensen, Peter


    Physical separation is pervasive in organizations, and has powerful effects on employee motivation and organizational behaviors. However, research shows that workplace separation is characterized by a variety of tradeoffs, tensions, and challenges that lead to both positive and negative outcomes....

  18. Selectivity in capillary electrokinetic separations

    NARCIS (Netherlands)

    de Zeeuw, R.A; de Jong, G.J.; Ensing, K


    This review gives a survey of selectivity modes in capillary electrophoresis separations in pharmaceutical analysis and bioanalysis. Despite the high efficiencies of these separation techniques, good selectivity is required to allow quantitation or identification of a Chemistry and Toxicology,

  19. Determine separations process strategy decision

    Energy Technology Data Exchange (ETDEWEB)

    Slaathaug, E.J.


    This study provides a summary level comparative analysis of selected, top-level, waste treatment strategies. These strategies include No Separations, Separations (high-level/low-level separations), and Deferred Separations of the tank waste. These three strategies encompass the full range of viable processing alternatives based upon full retrieval of the tank wastes. The assumption of full retrieval of the tank wastes is a predecessor decision and will not be revisited in this study.


    Directory of Open Access Journals (Sweden)

    Zaid A. Abdulrahman


    Full Text Available Simulated column performance curves were constructed for existing paraffin separation vacuum distillation column in LAB plant (Arab Detergent Company/Baiji-Iraq. The variables considered in this study are the thermodynamic model option, top vacuum pressure, top and bottom temperatures, feed temperature, feed composition & reflux ratio. Also simulated columns profiles for the temperature, vapor & liquid flow rates composition were constructed. Four different thermodynamic model options (SRK, TSRK, PR, and ESSO were used, affecting the results within 1-25% variation for the most cases.The simulated results show that about 2% to 8 % of paraffin (C10, C11, C12, & C13 present at the bottom stream which may cause a problem in the LAB plant. The major variations were noticed for the top temperature & the  paraffin weight fractions at bottom section with top vacuum pressure. The bottom temperature above 240 oC is not recommended because the total bottom flow rate decreases sharply, where as  the weight fraction of paraffins decrease slightly. The study gives evidence about a successful simulation with CHEMCAD

  1. Separators - Technology review: Ceramic based separators for secondary batteries (United States)

    Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram; Bazhenov, Vasilii; Schilm, Jochen; Leisegang, Tilmann; Meyer, Dirk C.


    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ("Energiewende") was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators

  2. Wastewater treatment with acoustic separator (United States)

    Kambayashi, Takuya; Saeki, Tomonori; Buchanan, Ian


    Acoustic separation is a filter-free wastewater treatment method based on the forces generated in ultrasonic standing waves. In this report, a batch-system separator based on acoustic separation was demonstrated using a small-scale prototype acoustic separator to remove suspended solids from oil sand process-affected water (OSPW). By applying an acoustic separator to the batch use OSPW treatment, the required settling time, which was the time that the chemical oxygen demand (COD) decreased to the environmental criterion (<200 mg/L), could be shortened from 10 to 1 min. Moreover, for a 10 min settling time, the acoustic separator could reduce the FeCl3 dose as coagulant in OSPW treatment from 500 to 160 mg/L.

  3. Separation process using microchannel technology (United States)

    Tonkovich, Anna Lee [Dublin, OH; Perry, Steven T [Galloway, OH; Arora, Ravi [Dublin, OH; Qiu, Dongming [Bothell, WA; Lamont, Michael Jay [Hilliard, OH; Burwell, Deanna [Cleveland Heights, OH; Dritz, Terence Andrew [Worthington, OH; McDaniel, Jeffrey S [Columbus, OH; Rogers, Jr; William, A [Marysville, OH; Silva, Laura J [Dublin, OH; Weidert, Daniel J [Lewis Center, OH; Simmons, Wayne W [Dublin, OH; Chadwell, G Bradley [Reynoldsburg, OH


    The disclosed invention relates to a process and apparatus for separating a first fluid from a fluid mixture comprising the first fluid. The process comprises: (A) flowing the fluid mixture into a microchannel separator in contact with a sorption medium, the fluid mixture being maintained in the microchannel separator until at least part of the first fluid is sorbed by the sorption medium, removing non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing first fluid from the sorption medium and removing desorbed first fluid from the microchannel separator. The process and apparatus are suitable for separating nitrogen or methane from a fluid mixture comprising nitrogen and methane. The process and apparatus may be used for rejecting nitrogen in the upgrading of sub-quality methane.

  4. Hereditary separability in Hausdorff continua

    Directory of Open Access Journals (Sweden)

    D. Daniel


    Full Text Available We consider those Hausdorff continua S such that each separable subspace of S is hereditarily separable. Due to results of Ostaszewski and Rudin, respectively, all monotonically normal spaces and therefore all continuous Hausdorff images of ordered compacta also have this property. Our study focuses on the structure of such spaces that also possess one of various rim properties, with emphasis given to rim-separability. In so doing we obtain analogues of results of M. Tuncali and I. Loncar, respectively.

  5. Gas separation membrane module assembly (United States)

    Wynn, Nicholas P [Palo Alto, CA; Fulton, Donald A [Fairfield, CA


    A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membranes, arranged within a housing. The housing contains a tube sheet that divides the space within the housing into two gas-tight spaces. A permeate collection system within the housing gathers permeate gas from the tubes for discharge from the housing.

  6. Noise source separation of diesel engine by combining binaural sound localization method and blind source separation method (United States)

    Yao, Jiachi; Xiang, Yang; Qian, Sichong; Li, Shengyang; Wu, Shaowei


    In order to separate and identify the combustion noise and the piston slap noise of a diesel engine, a noise source separation and identification method that combines a binaural sound localization method and blind source separation method is proposed. During a diesel engine noise and vibration test, because a diesel engine has many complex noise sources, a lead covering method was carried out on a diesel engine to isolate other interference noise from the No. 1-5 cylinders. Only the No. 6 cylinder parts were left bare. Two microphones that simulated the human ears were utilized to measure the radiated noise signals 1 m away from the diesel engine. First, a binaural sound localization method was adopted to separate the noise sources that are in different places. Then, for noise sources that are in the same place, a blind source separation method is utilized to further separate and identify the noise sources. Finally, a coherence function method, continuous wavelet time-frequency analysis method, and prior knowledge of the diesel engine are combined to further identify the separation results. The results show that the proposed method can effectively separate and identify the combustion noise and the piston slap noise of a diesel engine. The frequency of the combustion noise and the piston slap noise are respectively concentrated at 4350 Hz and 1988 Hz. Compared with the blind source separation method, the proposed method has superior separation and identification effects, and the separation results have fewer interference components from other noise.

  7. Conceptual design of distillation-based hybrid separation processes. (United States)

    Skiborowski, Mirko; Harwardt, Andreas; Marquardt, Wolfgang


    Hybrid separation processes combine different separation principles and constitute a promising design option for the separation of complex mixtures. Particularly, the integration of distillation with other unit operations can significantly improve the separation of close-boiling or azeotropic mixtures. Although the design of single-unit operations is well understood and supported by computational methods, the optimal design of flowsheets of hybrid separation processes is still a challenging task. The large number of operational and design degrees of freedom requires a systematic and optimization-based design approach. To this end, a structured approach, the so-called process synthesis framework, is proposed. This article reviews available computational methods for the conceptual design of distillation-based hybrid processes for the separation of liquid mixtures. Open problems are identified that must be addressed to finally establish a structured process synthesis framework for such processes.

  8. Advanced Aqueous Separation Systems for Actinide Partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Ken [Washington State Univ., Pullman, WA (United States); Martin, Leigh [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lumetta, Gregg [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    One of the most challenging aspects of advanced processing of used nuclear fuel is the separation of transplutonium actinides from fission product lanthanides. This separation is essential if actinide transmutation options are to be pursued in advanced fuel cycles, as lanthanides compete with actinides for neutrons in both thermal and fast reactors, thus limiting efficiency. The separation is difficult because the chemistry of Am3+ and Cm3+ is nearly identical to that of the trivalent lanthanides (Ln3+). The prior literature teaches that two approaches offer the greatest probability of devising a successful group separation process based on aqueous processes: 1) the application of complexing agents containing ligand donor atoms that are softer than oxygen (N, S, Cl-) or 2) changing the oxidation state of Am to the IV, V, or VI state to increase the essential differences between Am and lanthanide chemistry (an approach utilized in the PUREX process to selectively remove Pu4+ and UO22+ from fission products). The latter approach offers the additional benefit of enabling a separation of Am from Cm, as Cm(III) is resistant to oxidation and so can easily be made to follow the lanthanides. The fundamental limitations of these approaches are that 1) the soft(er) donor atoms that interact more strongly with actinide cations than lanthanides form substantially weaker bonds than oxygen atoms, thus necessitating modification of extraction conditions for adequate phase transfer efficiency, 2) soft donor reagents have been seen to suffer slow phase transfer kinetics and hydro-/radiolytic stability limitations and 3) the upper oxidation states of Am are all moderately strong oxidants, hence of only transient stability in media representative of conventional aqueous separations systems. There are examples in the literature of both approaches having been described. However, it is not clear at present that any extant process is sufficiently robust for application at the scale

  9. Complexity explained

    CERN Document Server

    Erdi, Peter


    This book explains why complex systems research is important in understanding the structure, function and dynamics of complex natural and social phenomena. Readers will learn the basic concepts and methods of complex system research.

  10. Molecular separation by thermosensitive hydrogelmembranes

    NARCIS (Netherlands)

    Feil, H.; Feil, Herman; Bae, You Han; Feijen, Jan; Kim, Sung Wan


    A new method for separation of molecules of different size is presented. The method is a useful addition to conventional separation methods which depend mainly on gel permeation chromatography using size exclusion. In the new method, hydrogel membranes are used which swelling level can be thermally

  11. Self Separation Support for UAS

    NARCIS (Netherlands)

    Tadema, J.; Theinissen, E.; Kirk, K.M.


    Recent guidance from the U.S. Federal Aviation Administration suggests that self separation needs to be a component of an Unmanned Aircraft System Sense and Avoid solution. The greater time horizon associated with self separation allows for pilot-in-the-loop operation, and, in fact, the nature of

  12. Parental separation and pediatric cancer

    DEFF Research Database (Denmark)

    Grant, Sally; Carlsen, Kathrine; Bidstrup, Pernille Envold Hansen


    The purpose of this study was to determine the risk for separation (ending cohabitation) of the parents of a child with a diagnosis of cancer.......The purpose of this study was to determine the risk for separation (ending cohabitation) of the parents of a child with a diagnosis of cancer....

  13. Family Separations in the Army (United States)


    assessment of readapting after last extended separation ......... ............. 68 14. Extent to which soldler/spouse needed time to readjust after separation...soldiers’ return ..... ....... ................... .... 71 16. Final model: Factors affecting time to readapt for spouses...anticipate that their own roles will have changed (Hunter, 1982). During the soldier’s absence, however, spouses have shouldered the responsibility of

  14. Vision 2020: 2000 Separations Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Adler, Stephen [Center for Waster Reduction Technologies; Beaver, Earl [Practical Sustainability; Bryan, Paul [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Robinson, Sharon [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watson, Jack [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)


    This report documents the results of four workshops on the technology barriers, research needs, and priorities of the chemical, agricultural, petroleum, and pharmaceutical industries as they relate to separation technologies utilizing adsorbents, crystallization, distillation, extraction, membranes, separative reactors, ion exchange, bioseparations, and dilute solutions.

  15. Separable metrics and radiating stars

    Indian Academy of Sciences (India)


    Dec 14, 2016 ... and expanding spherically symmetric radiating star. We transform the junction condition to an ordinary differ- ential equation by making a separability assumption on the metric functions in the space–time variables. The condition of separability on the metric functions yields several new exact solutions.

  16. Fast Monaural Separation of Speech

    DEFF Research Database (Denmark)

    Pontoppidan, Niels Henrik; Dyrholm, Mads


    a Factorial Hidden Markov Model, with non-stationary assumptions on the source autocorrelations modelled through the Factorial Hidden Markov Model, leads to separation in the monaural case. By extending Hansens work we find that Roweis' assumptions are necessary for monaural speech separation. Furthermore we...

  17. Magnetic separation in microfluidic systems

    DEFF Research Database (Denmark)

    Smistrup, Kristian


    , and it is argued that it is a good measure, when comparing the performance of magnetic bead separators. It is described how numeric modelling is used to aid the design of microfluidic magnetic separation systems. An example of a design optimization study is given. A robust fabrication scheme has been developed...... for fabrication of silicon based systems. This fabrication scheme is explained, and it is shown how, it is applied with variations for several designs of magnetic separators. An experimental setup for magnetic separation experiments has been developed. It has been coupled with an image analysis program......This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined...

  18. Separating Underdetermined Convolutive Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan


    A limitation in many source separation tasks is that the number of source signals has to be known in advance. Further, in order to achieve good performance, the number of sources cannot exceed the number of sensors. In many real-world applications these limitations are too restrictive. We propose...... a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...... techniques with binary time-frequency masking. In the proposed method, the number of source signals is not assumed to be known in advance and the number of sources is not limited to the number of microphones. Our approach needs only two microphones and the separated sounds are maintained as stereo signals....


    Directory of Open Access Journals (Sweden)

    Branimir Fuk


    Full Text Available Printed circuit boards from electronic waste are very important source of precious metals by recycling. The biggest challenge is liberation and separation of useful components; thin film which contains copper, zinc, tin, lead and precious metals like silver, gold and palladium from non useful components; polymers, ceramics and glass fibbers. The paper presents results for separation of shredded printed circuit boards from TV sets in electrostatic separator. Testing where conducted with material class 2/1 and 1/0.5 mm in laboratory on equipment for mineral processing. Results showed influence from independent variable; separation knife gradient, drum rotation speed and voltage on concentrate quality and recovery (the paper is published in Croatian.

  20. Pseudo-stationary separation materials for highly parallel separations.

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Anup K.; Palmer, Christopher (University of Montana, Missoula, MT)


    Goal of this study was to develop and characterize novel polymeric materials as pseudostationary phases in electrokinetic chromatography. Fundamental studies have characterized the chromatographic selectivity of the materials as a function of chemical structure and molecular conformation. The selectivities of the polymers has been studied extensively, resulting in a large body of fundamental knowledge regarding the performance and selectivity of polymeric pseudostationary phases. Two polymers have also been used for amino acid and peptide separations, and with laser induced fluorescence detection. The polymers performed well for the separation of derivatized amino acids, and provided some significant differences in selectivity relative to a commonly used micellar pseudostationary phase. The polymers did not perform well for peptide separations. The polymers were compatible with laser induced fluorescence detection, indicating that they should also be compatible with chip-based separations.

  1. On conformal minimal 2-spheres in complex Grassmann manifold G ...

    Indian Academy of Sciences (India)

    They classified the minimal two-spheres immersed in CPn and proved the rigidity theorems of conformal minimal two-spheres in CPn, but some of these properties are not inherited when the ambient space is G(k, n), k ≥ 2. The pseudo- holomorphic two-spheres in G(k, n) were studied by Jiao and Peng [10], Jiao [11] and.


    Pressly, R.E.


    Promethium-147 is separated from americium in acidic aqueous solution by adding fluosilicic acid to the solution, heating the solution to form a promethium precipitate and separating the precipitate from solution. The precipitate is then re-dissolved by ihe addition of boric acid and nitric acid, and re-precipitated by the addition of fluosilicic acid. This procedure is repeated six or more times to obtain a relatively americium-free promeihium precipitate. Americium may be separately recovered from the supernatant liquids. This process is applicable to the recovery of promethium from fission-product solutions which have been allowed to decay for a period of two to four years.

  3. Lunar Soil Particle Separator Project (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS improves ISRU oxygen...

  4. Lunar Soil Particle Separator Project (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS can improve ISRU oxygen...

  5. Continuous magnetic separator and process (United States)

    Oder, Robin R.; Jamison, Russell E.


    A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the discharge of a thickened slurry stream. Magnetic particles in the slurry are attracted to, and slide down, magnetic rods within the container. The slurry is thus separated into magnetic concentrate and clarified slurry. Flow control means can be used to control the ratio of the rate of magnetic concentrate to the rate of clarified slurry. Feed control means can be used to control the rate of slurry feed to the slurry inlet.

  6. Hydrodynamic separator sediment retention testing. (United States)


    Hydrodynamic separators are widely used in urban areas for removal of suspended sediments and floatables from : stormwater due to limited land availability for the installation of above ground stormwater best management : practices (BMPs). Hydrodynam...

  7. Gas separations using inorganic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Egan, B.Z.; Singh, S.P.N. [Oak Ridge National Lab., TN (United States); Fain, D.E.; Roettger, G.E.; White, D.E. [Oak Ridge K-25 Site, TN (United States)


    This report summarizes the results from a research and development program to develop, fabricate, and evaluate inorganic membranes for separating gases at high temperatures and pressures in hostile process environments encountered in fossil energy conversion processes such as coal gasification. The primary emphasis of the research was on the separation and recovery of hydrogen from synthesis gas. Major aspects of the program included assessment of the worldwide research and development activity related to gas separations using inorganic membranes, identification and selection of candidate membrane materials, fabrication and characterization of membranes using porous membrane technology developed at the Oak Ridge K-25 Site, and evaluation of the separations capability of the fabricated membranes in terms of permeabilities and fluxes of gases.

  8. Selective Photoinitiated Electrophoretic Separator Project (United States)

    National Aeronautics and Space Administration — To address NASA Johnson Space Center needs for gas separation and collection technology for lunar in-situ resource utilization, Physical Optics Corporation (POC)...

  9. Mathematical modelling of membrane separation

    DEFF Research Database (Denmark)

    Vinther, Frank

    This thesis concerns mathematical modelling of membrane separation. The thesis consists of introductory theory on membrane separation, equations of motion, and properties of dextran, which will be the solute species throughout the thesis. Furthermore, the thesis consist of three separate...... mathematical models, each with a different approach to membrane separation. The first model is a statistical model investigating the interplay between solute shape and the probability of entering the membrane. More specific the transition of solute particles from being spherical to becoming more elongated...... as prolate ellipsoids with the same volume. The porous membrane is assumed isotropic such that the model reduces to a two dimensional model. With this assumption ellipsoids with the same volume reduces to ellipses with the same area. The model finds the probability of entering the pore of the membrane...

  10. Recent Development in Flow Separation. (United States)


    with Cylinder and 375 Cone 3.2.3 Interference of Tilted Cylinder 377 iv -J. ..-- ’ ’ - - .o, . 3.2.4 Jet Interference 378 3.2.5 Interference of Sharp... overexpands first, then is recompressed by the lip shocks, and this is caused essentially by a viscous separation effect similar to the separation shock...Heating Involving Protuberance cecentlv, in the USSR, by mounting the simply shaped bodies such as a strai;7ht and tilted cylinder, a triangular wing

  11. Optics of mass separator I

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, S.J.


    The ion optics of an existing mass separator are documented. The elctrostatic and magnetic stages are analyzed theoretically, both separately and in combination, by paying particular attention to the ion trajectories, the linear and angular magnifications, and the dispersion. The possibility of converting the magnet into a tunable unit by means of current-carrying elements in the gap is demonstrated. The feasibility of correction coils constructed from printed circuit board is shown.

  12. Fuel-Cell Water Separator (United States)

    Burke, Kenneth Alan; Fisher, Caleb; Newman, Paul


    The main product of a typical fuel cell is water, and many fuel-cell configurations use the flow of excess gases (i.e., gases not consumed by the reaction) to drive the resultant water out of the cell. This two-phase mixture then exits through an exhaust port where the two fluids must again be separated to prevent the fuel cell from flooding and to facilitate the reutilization of both fluids. The Glenn Research Center (GRC) has designed, built, and tested an innovative fuel-cell water separator that not only removes liquid water from a fuel cell s exhaust ports, but does so with no moving parts or other power-consuming components. Instead it employs the potential and kinetic energies already present in the moving exhaust flow. In addition, the geometry of the separator is explicitly intended to be integrated into a fuel-cell stack, providing a direct mate with the fuel cell s existing flow ports. The separator is also fully scalable, allowing it to accommodate a wide range of water removal requirements. Multiple separators can simply be "stacked" in series or parallel to adapt to the water production/removal rate. GRC s separator accomplishes the task of water removal by coupling a high aspect- ratio flow chamber with a highly hydrophilic, polyethersulfone membrane. The hydrophilic membrane readily absorbs and transports the liquid water away from the mixture while simultaneously resisting gas penetration. The expansive flow path maximizes the interaction of the water particles with the membrane while minimizing the overall gas flow restriction. In essence, each fluid takes its corresponding path of least resistance, and the two fluids are effectively separated. The GRC fuel-cell water separator has a broad range of applications, including commercial hydrogen-air fuel cells currently being considered for power generation in automobiles.

  13. Magnetic separation of antibiotics by electrochemical magnetic seeding

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, I; Toyoda, K [Department of Agricultural Engineering and Socio Economics, Kobe University, Nada, Kobe 657-8501 (Japan); Beneragama, N; Umetsu, K [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555 (Japan)], E-mail:


    Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.

  14. Launch Vehicle Ascent Stage Separation Wind Tunnel Test (United States)

    Bordelon, Wayne; Frost, Alonzo; Pritchett, Victor


    The Aerodynamic Research Facility (ARF) LGBB (Liquid Glide-back Booster) Stage Separation Test is part of the Multi-Center Second Generation In-House Tool Development Task. The ARF LGBB Stage Separation Test has been completed at MSFC (Marshall Space Flight Center). It includes the following: PSP (Project Study Plan) Feasibility Test; Isolated Force/Moment Data; Bimese Configuration Force/Moment Data; Schlieren Video. The LGBB Bimese Reference Configuration Analyses and Test Results In-Work to Develop Tools and Database. Preliminary results showed qualitative agreement with CFD (computational fluid dynamics) aerodynamic predictions. The preliminary results exhibit the complex nature of the stage separation aerothermal problem.

  15. Pigment-protein complexes

    Energy Technology Data Exchange (ETDEWEB)

    Siegelman, H W


    The photosynthetically-active pigment protein complexes of procaryotes and eucaryotes include chlorophyll proteins, carotenochlorophyll proteins, and biliproteins. They are either integral components or attached to photosynthetic membranes. Detergents are frequently required to solubilize the pigment-protein complexes. The membrane localization and detergent solubilization strongly suggest that the pigment-protein complexes are bound to the membranes by hydrophobic interactions. Hydrophobic interactions of proteins are characterized by an increase in entropy. Their bonding energy is directly related to temperature and ionic strength. Hydrophobic-interaction chromatography, a relatively new separation procedure, can furnish an important method for the purification of pigment-protein complexes. Phycobilisome purification and properties provide an example of the need to maintain hydrophobic interactions to preserve structure and function.

  16. Vector bundles on complex projective spaces with an appendix by S. I. Gelfand

    CERN Document Server

    Okonek, Christian; Spindler, Heinz


    This expository treatment is based on a survey given by one of the authors at the Séminaire Bourbaki in November 1978 and on a subsequent course held at the University of Göttingen. It is intended to serve as an introduction to the topical question of classification of holomorphic vector bundles on complex projective spaces, and can easily be read by students with a basic knowledge of analytic or algebraic geometry. Short supplementary sections describe more advanced topics, further results, and unsolved problems. This is a corrected third printing with an Appendix by S. I. Gelfand.  ------   The present book is the first one, within the extensive literature on algebraic vector bundles, to give both a self-contained introduction to the basic methods and an exposition of the current state of the classification theory of algebraic vector bundles over Pn(C). (…) The reviewer thinks that readers should be grateful to the authors for presenting the first detailed, self-contained and systematic textbook on ve...

  17. Molten carbonate fuel cell separator (United States)

    Nickols, R.C.


    In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

  18. Separation of attractors in 1-modulus quantum corrected special geometry

    CERN Document Server

    Bellucci, S; Marrani, A; Shcherbakov, A


    We study the solutions to the N=2, d=4 Attractor Equations in a dyonic, extremal, static, spherically symmetric and asymptotically flat black hole background, in the simplest case of perturbative quantum corrected cubic Special Kahler geometry consistent with continuous axion-shift symmetry, namely in the 1-modulus Special Kahler geometry described (in a suitable special symplectic coordinate) by the holomorphic Kahler gauge-invariant prepotential F=t^3+i*lambda, with lambda real. By performing computations in the ``magnetic'' charge configuration, we find evidence for interesting phenomena (absent in the classical limit of vanishing lambda). Namely, for a certain range of the quantum parameter lambda we find a ``splitting'' of attractors, i.e. the existence of multiple solutions to the Attractor Equations for fixed supporting charge configuration. This corresponds to the existence of ``area codes'' in the radial evolution of the scalar t, determined by the various disconnected regions of the moduli space, wh...

  19. Complex Narratives

    NARCIS (Netherlands)

    Simons, J.; Buckland, W.


    In the opening chapter, "Complex Narratives," Jan Simons brings together narratology, game theory, and complexity theory to untangle the intricate nature of complex narratives in contemporary cinema. He presents an overview of the different concepts - forking path narratives, mind-game films,

  20. (II) complexes

    African Journals Online (AJOL)

    activities of Schiff base tin (II) complexes. Neelofar1 ... Conclusion: All synthesized Schiff bases and their Tin (II) complexes showed high antimicrobial and ...... Singh HL. Synthesis and characterization of tin (II) complexes of fluorinated Schiff bases derived from amino acids. Spectrochim Acta Part A: Molec Biomolec.

  1. Separable and Inseparable Quantum Trajectories (United States)

    Sperling, J.; Walmsley, I. A.


    The dynamical behavior of interacting systems plays a fundamental role for determining quantum correlations, such as entanglement. In this Letter, we describe temporal quantum effects of the inseparable evolution of composite quantum states by comparing the trajectories to their classically correlated counterparts. For this reason, we introduce equations of motions describing the separable propagation of any interacting quantum system, which are derived by requiring separability for all times. The resulting Schrödinger-type equations allow for comparing the trajectories in a separable configuration with the actual behavior of the system and, thereby, identifying inseparable and time-dependent quantum properties. As an example, we study bipartite discrete- and continuous-variable interacting systems. The generalization of our developed technique to multipartite scenarios is also provided.

  2. Continuous-flow sheathless diamagnetic particle separation in ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yilong [Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921 (United States); Song, Le [School of Instrument Science and Opto-electronic Engineering, Hefei University of Technology, Hefei 230009 (China); Yu, Liandong, E-mail: [School of Instrument Science and Opto-electronic Engineering, Hefei University of Technology, Hefei 230009 (China); Xuan, Xiangchun, E-mail: [Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921 (United States)


    Separating particles from a complex mixture is often necessary in many chemical and biomedical applications. This work presents a continuous-flow sheathless diamagnetic particle separation in ferrofluids through U-shaped microchannels. Due to the action of a size-dependent magnetic force, diamagnetic particles are focused into a single stream in the inlet branch of the U-turn and then continuously separated into two streams in its outlet branch. A 3D numerical model is developed to predict and understand the diamagnetic particle transport during this separation process. The numerical predictions are found to agree well with the experimental observations in a systematic study of the effects of multiple parameters including ferrofluid flow rate, concentration and magnet-channel distance. Additional numerical studies of the geometric effects of the U-turn reveal that increasing the outlet-branch width of the U-turn can significantly enhance the diamagnetic particle separation in ferrofluids. - Highlights: • Particles are focused and separated in the two branches of a U-shaped microchannel. • Negative magnetophoretic motion in ferrofluids causes the particle deflection. • A 3D numerical model is developed to simulate the particle separation. • Multiple parametric effects are studied both experimentally and numerically. • Increasing the outlet-branch width significantly enhances the particle separation.

  3. Rotatingwall Technique and Centrifugal Separation (United States)

    Anderegg, François

    This chapter describes the "rotating wall" technique which enables essentially unlimited confinement time of 109-1010 charged particles in a Penning trap. The applied rotating wall electric field provides a positive torque that counteracts background drags, resulting in radial compression or steady-state confinement in near-thermal equilibrium states. The last part of the chapter discusses centrifugal separation in a rotating multi-species non-neutral plasma. Separation occurs when the centrifugal energy is larger than the mixing due to thermal energy.

  4. Chiral separation by capillary electrochromatography. (United States)

    Gübitz, G; Schmid, M G


    The state of art in chiral capillary electrochromatography is reviewed. Chiral separations by capillary electrochromatography were carried out using capillaries packed with chiral stationary phases or achiral stationary phases in combination with a chiral selector added to the mobile phase. Furthermore, the use of open tubular capillaries containing the chiral selector coated to the capillary wall was also reported. Among other separation principles moleculary imprinted polymers represent a challenging approach for chiral capillary electrochromatography. A recent trend is the use of polymeric continuous beds with a chiral selector incorporated.

  5. Coleman automorphisms of holomorphs of completely reducible and ...

    Indian Academy of Sciences (India)


    for the Doctoral Program of Higher Education of China (20133706110002), Natural Science Founda- tion of Shandong Province ... Province (201602035) and Project of Shandong Province Higher Educational Science and Technology. Program (J14LI10). Manuscript ... First we fix some notation. Let K ≤ G and σ ∈ Aut(G).

  6. Determinantal Point Processes Associated with Hilbert Spaces of Holomorphic Functions (United States)

    Bufetov, Alexander I.; Qiu, Yanqi


    We study determinantal point processes on C induced by the reproducing kernels of generalized Fock spaces as well as those on the unit disc D induced by the reproducing kernels of generalized Bergman spaces. In the first case, we show that all reduced Palm measures of the same order are equivalent. The Radon-Nikodym derivatives are computed explicitly using regularized multiplicative functionals. We also show that these determinantal point processes are rigid in the sense of Ghosh and Peres, hence reduced Palm measures of different orders are singular. In the second case, we show that all reduced Palm measures, of all orders, are equivalent. The Radon-Nikodym derivatives are computed using regularized multiplicative functionals associated with certain Blaschke products. The quasi-invariance of these determinantal point processes under the group of diffeomorphisms with compact supports follows as a corollary.

  7. Immobile Complex Verbs in Germanic

    DEFF Research Database (Denmark)

    Vikner, Sten


    Certain complex verbs in Dutch, German, and Swiss German do not undergo verb movement. The suggestion to be made in this article is that these ‘‘immobile'' verbs have to fulfill both the requirements imposed on complex verbs of the V° type (=verbs with non-separable prefixes) and the requirements...... imposed on complex verbs of the V* type (=verbs with separable prefixes). This results in such verbs being morphologically unexceptional, i.e., having a full set of forms but syntactically peculiar (‘‘immobile''), i.e., they can only occur in their base position. Any movement is incompatible with either...... (and why this single prefix-like part may NOT be a particle), - why immobile verbs even include verbs with two prefix-like parts, where each of these are separable particles (as in, e.g., German voranmelden ‘preregister'), - why there is such a great amount of speaker variation as to which verbs...

  8. Pediatric Disability and Caregiver Separation (United States)

    McCoyd, Judith L. M.; Akincigil, Ayse; Paek, Eun Kwang


    The evidence that the birth of a child with a disability leads to divorce or separation is equivocal, with the majority of recent research suggesting that such a birth and childrearing may be stressful, but not necessarily toxic, to the caregiver relationship. Such research has been limited by small sample sizes and nonrepresentative samples and…

  9. Separation technology 2005; Separasjonsteknologi 2005

    Energy Technology Data Exchange (ETDEWEB)



    The conference comprises 13 presentations on the topics of separation technology aspects with emphasis on technology assessment. Some topics of particular interest are emulsion stabilization, sand technology and handling, water handling and reservoir injection, technical equipment and compression and pressure aspects.

  10. Experimentally accessible geometrical separability criteria

    Energy Technology Data Exchange (ETDEWEB)

    Badziag, Piotr [Alba Nova Fysikum, University of Stockholm, S-106 91 Stockholm (Sweden); Brukner, Caslav; Paterek, Tomasz [Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna (Austria); Laskowski, Wieslaw; Zukowski, Marek [Institute of Theoretical Physics and Astrophysics, University of Gdansk, ul.Wita Stwosza 57, PL-80-952 Gdansk (Poland)], E-mail:


    We present an intuitive geometrical approach to entanglement detection. It allows one to formulate simple and experimentally feasible sufficient conditions for entanglement. Within the approach we derive the necessary and sufficient condition for separability and discuss its relation with entanglement witnesses and positive maps.

  11. Continuous-Flow Centrifugal Separator (United States)

    Waldron, Robert D.


    Apparatus combines principles of centrifugal and cyclone separators to control movement of solid or liquid particles suspended in flowing gas. Spinning disk contains radial channels, width varys as function of distance from center. Gas flows from outer ring around disk toward center. Particles in gas collected at periphery, center or both.

  12. Working inside an electrostatic separator

    CERN Multimedia


    This type of separators with electrodes of a length of 2 m and a field of 100 kV/cm were still in use for secondary beams in the East Hall at the PS. Michel Zahnd is on foreground, left, and Pierre Simon on background, right.

  13. Separating Device for solid Particles

    NARCIS (Netherlands)

    De Jong, T.P.R.; Kattentidt, H.U.R.; Schokker, E.A.


    The invention relates to a separating device for solid fragments, comprising a conveyor belt for supplying the fragments, at least one sensor for detecting the fragments, and an ejector for dislodging the fragments from the belt. The ejector is embodied as mechanical impulse-transmitting organ

  14. 33rd Actinide Separations Conference

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, L M; Wilk, P A


    Welcome to the 33rd Actinide Separations Conference hosted this year by the Lawrence Livermore National Laboratory. This annual conference is centered on the idea of networking and communication with scientists from throughout the United States, Britain, France and Japan who have expertise in nuclear material processing. This conference forum provides an excellent opportunity for bringing together experts in the fields of chemistry, nuclear and chemical engineering, and actinide processing to present and discuss experiences, research results, testing and application of actinide separation processes. The exchange of information that will take place between you, and other subject matter experts from around the nation and across the international boundaries, is a critical tool to assist in solving both national and international problems associated with the processing of nuclear materials used for both defense and energy purposes, as well as for the safe disposition of excess nuclear material. Granlibakken is a dedicated conference facility and training campus that is set up to provide the venue that supports communication between scientists and engineers attending the 33rd Actinide Separations Conference. We believe that you will find that Granlibakken and the Lake Tahoe views provide an atmosphere that is stimulating for fruitful discussions between participants from both government and private industry. We thank the Lawrence Livermore National Laboratory and the United States Department of Energy for their support of this conference. We especially thank you, the participants and subject matter experts, for your involvement in the 33rd Actinide Separations Conference.

  15. Explaining outliers by subspace separability

    DEFF Research Database (Denmark)

    Micenková, Barbora; Ng, Raymond T.; Dang, Xuan-Hong


    for the outlier. These explanations are expressed in the form of subspaces in which the given outlier shows separability from the inliers. In this manner, our proposed method complements existing outlier detection algorithms by providing additional information about the outliers. Our method is designed to work...

  16. Convolutive Blind Source Separation Methods

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Larsen, Jan; Kjems, Ulrik


    During the past decades, much attention has been given to the separation of mixed sources, in particular for the blind case where both the sources and the mixing process are unknown and only recordings of the mixtures are available. In several situations it is desirable to recover all sources fro...

  17. Gas Separations using Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Paul KT Liu


    This project has been oriented toward the development of a commercially viable ceramic membrane for high temperature gas separations. A technically and commercially viable high temperature gas separation membrane and process has been developed under this project. The lab and field tests have demonstrated the operational stability, both performance and material, of the gas separation thin film, deposited upon the ceramic membrane developed. This performance reliability is built upon the ceramic membrane developed under this project as a substrate for elevated temperature operation. A comprehensive product development approach has been taken to produce an economically viable ceramic substrate, gas selective thin film and the module required to house the innovative membranes for the elevated temperature operation. Field tests have been performed to demonstrate the technical and commercial viability for (i) energy and water recovery from boiler flue gases, and (ii) hydrogen recovery from refinery waste streams using the membrane/module product developed under this project. Active commercializations effort teaming with key industrial OEMs and end users is currently underway for these applications. In addition, the gas separation membrane developed under this project has demonstrated its economical viability for the CO2 removal from subquality natural gas and landfill gas, although performance stability at the elevated temperature remains to be confirmed in the field.

  18. Separable metrics and radiating stars

    Indian Academy of Sciences (India)

    We study the junction condition relating the pressure to heat flux at the boundary of an accelerating and expanding spherically symmetric radiating star. We transform the junction condition to an ordinary differential equation by making a separability assumption on the metric functions in the space–time variables.

  19. Development of Separator for Soybeans

    NARCIS (Netherlands)

    Vries, de H.C.P.; Rijpma, P.J.; Owaa, J.S.E.


    A simple and effective separator for soybeans was developed for small-scale farmers in Uganda, to clean the seeds from foreign material, chaff, broken beans etc. as demanded by local and world markets. It will help to avoid losses during post-harvest time and to reduce human drudgery of cleaning the

  20. Separability by piecewise testable languages is PTime-complete

    Czech Academy of Sciences Publication Activity Database

    Masopust, Tomáš


    Roč. 711, February 8 (2018), s. 109-114 ISSN 0304-3975 Institutional support: RVO:67985840 Keywords : separability * piecewise testable languages * complexity Subject RIV: BA - General Mathematics Impact factor: 0.698, year: 2016

  1. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator (United States)

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.


    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  2. Complexity Plots

    KAUST Repository

    Thiyagalingam, Jeyarajan


    In this paper, we present a novel visualization technique for assisting the observation and analysis of algorithmic complexity. In comparison with conventional line graphs, this new technique is not sensitive to the units of measurement, allowing multivariate data series of different physical qualities (e.g., time, space and energy) to be juxtaposed together conveniently and consistently. It supports multivariate visualization as well as uncertainty visualization. It enables users to focus on algorithm categorization by complexity classes, while reducing visual impact caused by constants and algorithmic components that are insignificant to complexity analysis. It provides an effective means for observing the algorithmic complexity of programs with a mixture of algorithms and black-box software through visualization. Through two case studies, we demonstrate the effectiveness of complexity plots in complexity analysis in research, education and application. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  3. carbene complexes

    Indian Academy of Sciences (India)


    Abstract. Reaction of oligomeric Cu(I) complexes [Cu{µ-S-C(=NR)(O–Ar–CH3)}]n with Lewis acids gave Cu(I) carbene complexes, which were characterized by 1H and 13C NMR spectroscopy. Cu(I) car- bene complexes could be directly generated from RNCS, Cu(I)–OAr and Lewis acids; this method can be used to ...

  4. Tramp ship routing and scheduling with voyage separation requirements

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte; Lusby, Richard Martin; Larsen, Jesper


    in time. We have developed a new and exact branch-and-price procedure for this problem. We use a dynamic programming algorithm to generate columns and describe a time window branching scheme used to enforce the voyage separation requirements which we relax in the master problem. Computational results show...... in the spot market. Routing and scheduling a tramp fleet to best utilise fleet capacity according to current demand is therefore an ongoing and complicated problem. Here we add further complexity to the routing and scheduling problem by incorporating voyage separation requirements that enforce a minimum time...... spread between some voyages. The incorporation of these separation requirements helps balance the conflicting objectives of maximising profit for the tramp operator and minimising inventory costs for the charterer, since these costs increase if similar voyages are not performed with some separation...

  5. Teaching Separations: Why, What, When, and How? (United States)

    Wankat, Phillip C.


    Describes how and when to teach separation science to chemical engineering students. Separation science is important for industrial businesses involving the manufacture of adsorption systems, distillation columns, extractors, and other separation equipment and techniques. (Contains 13 references.) (YDS)

  6. Adsorption Model for Off-Gas Separation

    Energy Technology Data Exchange (ETDEWEB)

    Veronica J. Rutledge


    The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed in gPROMS software. Inputs include gas stream constituents, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. It models dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions for a multiple component gas stream. The simulation outputs component concentrations along the column length as a function of time from which the breakthrough data is obtained. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data will be input into the adsorption model to develop a model specific for iodine adsorption on silver mordenite as well as model(s) specific for krypton and xenon adsorption. The model will be validated with experimental breakthrough curves. Another future off-gas modeling goal is to develop a model for the unit operation absorption. The off-gas models will be made available via the server or web for evaluation by customers.

  7. Magnetic Separator Enhances Treatment Possibilities (United States)


    Since the earliest missions in space, NASA specialists have performed experiments in low gravity. Protein crystal growth, cell and tissue cultures, and separation technologies such as electrophoresis and magnetophoresis have been studied on Apollo 14, Apollo 16, STS-107, and many other missions. Electrophoresis and magnetophoresis, respectively, are processes that separate substances based on the electrical charge and magnetic field of a molecule or particle. Electrophoresis has been studied on over a dozen space shuttle flights, leading to developments in electrokinetics, which analyzes the effects of electric fields on mass transport (atoms, molecules, and particles) in fluids. Further studies in microgravity will continue to improve these techniques, which researchers use to extract cells for various medical treatments and research.

  8. Separation-individuation and cognition. (United States)

    Lester, E P


    Through direct observation of infants and mothers in an "experimental" nursery, Mahler and her associates have accumulated data which when analyzed point to distinct phases (stages) during the long process of the development of the concepts of self and object. These phases, autism, symbiosis, and separation-individuation (itself subdivided into four subphases, differentiation, practicing, rapprochement, and consolidation of individuation) correspond well with the stages described by Piaget as constituting the period of cognitive growth described as sensorimotor intelligence. The intercorrelation of the phasic development along these two separate lines (objectal-affective and cognitive), expectable as it may be, is of considerable interest as it underlines the intrinsic strength of the psychoanalytic concept of the object. Furthermore, this intercorrelation enhances and enlarges our understanding of the process of consolidation of self and object during the first years of life.

  9. Fragment separator momentum compression schemes

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, Laura, E-mail: [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); National Superconducting Cyclotron Lab, Michigan State University, 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Erdelyi, Bela [Argonne National Laboratory, Argonne, IL 60439 (United States); Northern Illinois University, DeKalb, IL 60115 (United States); Hausmann, Marc [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Kubo, Toshiyuki [RIKEN Nishina Center, RIKEN, Wako (Japan); Nolen, Jerry [Argonne National Laboratory, Argonne, IL 60439 (United States); Portillo, Mauricio [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Sherrill, Bradley M. [National Superconducting Cyclotron Lab, Michigan State University, 1 Cyclotron, East Lansing, MI 48824-1321 (United States)


    We present a scheme to use a fragment separator and profiled energy degraders to transfer longitudinal phase space into transverse phase space while maintaining achromatic beam transport. The first order beam optics theory of the method is presented and the consequent enlargement of the transverse phase space is discussed. An interesting consequence of the technique is that the first order mass resolving power of the system is determined by the first dispersive section up to the energy degrader, independent of whether or not momentum compression is used. The fragment separator at the Facility for Rare Isotope Beams is a specific application of this technique and is described along with simulations by the code COSY INFINITY.

  10. Fragment separator momentum compression schemes.

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, L.; Erdelyi, B.; Hausmann, M.; Kubo, T.; Nolen, J.; Portillo, M.; Sherrill, B.M. (Physics); (MSU); (Northern Illinois Univ.); (RIKEN)


    We present a scheme to use a fragment separator and profiled energy degraders to transfer longitudinal phase space into transverse phase space while maintaining achromatic beam transport. The first order beam optics theory of the method is presented and the consequent enlargement of the transverse phase space is discussed. An interesting consequence of the technique is that the first order mass resolving power of the system is determined by the first dispersive section up to the energy degrader, independent of whether or not momentum compression is used. The fragment separator at the Facility for Rare Isotope Beams is a specific application of this technique and is described along with simulations by the code COSY INFINITY.

  11. Fragment separator momentum compression schemes (United States)

    Bandura, Laura; Erdelyi, Bela; Hausmann, Marc; Kubo, Toshiyuki; Nolen, Jerry; Portillo, Mauricio; Sherrill, Bradley M.


    We present a scheme to use a fragment separator and profiled energy degraders to transfer longitudinal phase space into transverse phase space while maintaining achromatic beam transport. The first order beam optics theory of the method is presented and the consequent enlargement of the transverse phase space is discussed. An interesting consequence of the technique is that the first order mass resolving power of the system is determined by the first dispersive section up to the energy degrader, independent of whether or not momentum compression is used. The fragment separator at the Facility for Rare Isotope Beams is a specific application of this technique and is described along with simulations by the code COSY INFINITY.

  12. Causal and causally separable processes (United States)

    Oreshkov, Ognyan; Giarmatzi, Christina


    The idea that events are equipped with a partial causal order is central to our understanding of physics in the tested regimes: given two pointlike events A and B, either A is in the causal past of B, B is in the causal past of A, or A and B are space-like separated. Operationally, the meaning of these order relations corresponds to constraints on the possible correlations between experiments performed in the vicinities of the respective events: if A is in the causal past of B, an experimenter at A could signal to an experimenter at B but not the other way around, while if A and B are space-like separated, no signaling is possible in either direction. In the context of a concrete physical theory, the correlations compatible with a given causal configuration may obey further constraints. For instance, space-like correlations in quantum mechanics arise from local measurements on joint quantum states, while time-like correlations are established via quantum channels. Similarly to other variables, however, the causal order of a set of events could be random, and little is understood about the constraints that causality implies in this case. A main difficulty concerns the fact that the order of events can now generally depend on the operations performed at the locations of these events, since, for instance, an operation at A could influence the order in which B and C occur in A’s future. So far, no formal theory of causality compatible with such dynamical causal order has been developed. Apart from being of fundamental interest in the context of inferring causal relations, such a theory is imperative for understanding recent suggestions that the causal order of events in quantum mechanics can be indefinite. Here, we develop such a theory in the general multipartite case. Starting from a background-independent definition of causality, we derive an iteratively formulated canonical decomposition of multipartite causal correlations. For a fixed number of settings and

  13. Separations innovative concepts: Project summary

    Energy Technology Data Exchange (ETDEWEB)

    Lee, V.E. (ed.)


    This project summary includes the results of 10 innovations that were funded under the US Department's Innovative Concept Programs. The concepts address innovations that can substantially reduce the energy used in industrial separations. Each paper describes the proposed concept, and discusses the concept's potential energy savings, market applications, technical feasibility, prior work and state of the art, and future development needs.

  14. Selective Photo-Initiated Electrophoretic Separator Project (United States)

    National Aeronautics and Space Administration — Physical Optics Corporation (POC) proposes to develop a Selective Photoinitiated Electrophoretic Separator (SPIES) System to address NASA's volatile gas separation...

  15. Computational Complexity

    Directory of Open Access Journals (Sweden)

    J. A. Tenreiro Machado


    Full Text Available Complex systems (CS involve many elements that interact at different scales in time and space. The challenges in modeling CS led to the development of novel computational tools with applications in a wide range of scientific areas. The computational problems posed by CS exhibit intrinsic difficulties that are a major concern in Computational Complexity Theory. [...

  16. Complex narratives

    NARCIS (Netherlands)

    Simons, J.


    This paper brings together narratology, game theory, and complexity theory to untangle the intricate nature of complex narratives in contemporary cinema. It interrogates the different terms - forking-path narratives, mind-game films, modular narratives, multiple-draft films, database narratives,

  17. Communication Complexity

    Indian Academy of Sciences (India)

    Jaikumar Radhakrishnan

    Communication complexity. Strategy I. Alice x ∈ {0, 1}n. ⇒. ⇐. Bob y ∈ {0, 1}n. Naive strategy. Alice sends x to Bob. Bob tells Alice if x = y. Cost. Requires n + 1 bits of communication. Jaikumar Radhakrishnan. Communication Complexity ...

  18. Complexity Theory (United States)

    Lee, William H K.


    A complex system consists of many interacting parts, generates new collective behavior through self organization, and adaptively evolves through time. Many theories have been developed to study complex systems, including chaos, fractals, cellular automata, self organization, stochastic processes, turbulence, and genetic algorithms.

  19. Complex derivatives (United States)

    Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph


    The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

  20. Complex variables

    CERN Document Server

    Fisher, Stephen D


    The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

  1. Center for Advanced Separation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, Rick


    The U.S. is the largest producer of mining products in the world. In 2011, U.S. mining operations contributed a total of $232 billion to the nation’s GDP plus $138 billion in labor income. Of this the coal mining industry contributed a total of $97.5 billion to GDP plus $53 billion in labor income. Despite these contributions, the industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations. Originally set up by Virginia Tech and West Virginia University, CAST is now a five-university consortium – Virginia Tech, West Virginia University, University of Kentucky, University of Utah and Montana Tech, - that is supported through U.S. DOE Cooperative Agreement No. DE-FE0000699, Center for Advanced Separation Technology. Much of the research to be conducted with Cooperative Agreement funds will be longer term, high-risk, basic research and will be carried out in two broad areas: Advanced Pre-Combustion Clean Coal Technologies and Gas-Gas Separations. Distribution of funds is handled via competitive solicitation of research proposals through Site Coordinators at the five member universities. These were reviewed and the selected proposals were forwarded these to the DOE/NETL Project Officer for final review and approval. The successful projects are listed below by category, along with abstracts from their final reports.

  2. Ceramic membranes for gas separation

    Energy Technology Data Exchange (ETDEWEB)

    Vincente-Mingarro, I.M. de; Pitarch, J.A. [Tecnologia y Gestion de la Innovacion, Madrid (Spain)


    The project is being carried out jointly by TGI, S.A., CIEMAT and CSIC-ICM to develop and evaluate new inorganic membranes of a ceramic type, with nanometric pore size for separation of contaminants and fuel enrichment, in gas mixtures from coal gasification. In order to achieve both the highest active and selective surface, a candle (150 mm length and 60 mm in diameter), with 30-40 % porosity and pore sizes of {lt}1 {mu}m was developed. The processing steps include the slip-casting of the first layer (porous support) in a way than after thermal treatment (1400-1600{degree}C) the desirable shape dimensions, strength, porosity and pore size were obtained. Then the support was dipped successively (colloidal filtration over the casting porous piece) in an appropriate suspension of alumina with lower grain size. The top layer was obtained by the sol-gel process so that through successive setting and heat treatment the pores were reduced to the nanometre size. CVD and CVI techniques were set up to develop membranes for gas separation with a high selectivity level. Experimental chemical infiltration `Membranes Development` on porous substrates has been achieved on disk and candle-shaped materials. Characterisation was by spectrophotometry (IRS). Kinetic studies of coating in order to find out reproducible conditions at low temperature were also carried out. Uniform recovery over the whole membrane surface is wanted. The CIEMAT`s Hot Gas Separation Plant (HGSP) works with gas mixtures at a maximum design temperature 773 K and pressures up to 50 bar. It comprises: a gas supply unit equipped with flow, temperature and pressure measuring and control systems; a heating system within the membrane which must be leak proof for high pressures; and an in-line gas chromatography system thus allowing the chemical composition of the gas entering, permeated and retained to be measured. 7 figs.

  3. Revisiting separation properties of convex fuzzy sets (United States)

    Separation of convex sets by hyperplanes has been extensively studied on crisp sets. In a seminal paper separability and convexity are investigated, however there is a flaw on the definition of degree of separation. We revisited separation on convex fuzzy sets that have level-wise (crisp) disjointne...

  4. Materials for carbon dioxide separation

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Qingqing


    The CO{sub 2} adsorption capacities at room temperature have been investigated by comparing carbon nanotubes, fullerene, graphenes, graphite and granular activated carbons. It turned out that the amount of the micropore surface area was dominating the CO{sub 2} adsorption ability. Another promising class of materials for CO{sub 2} capture and separation are CaO derived from the eggshells. Two aspects were studied in present work: a new hybrid materials synthesized by doping the CaTiO{sub 3} and the relationship between physisorption and chemisorption properties of CaO-based materials.

  5. Separations method for polar molecules (United States)

    Thoma, Steven G.; Bonhomme, Francois R.


    A method for separating at least one compound from a liquid mixture containing different compounds where anew crystalline manganese phosphate composition with the formula Mn.sub.3 (PO.sub.4).sub.4.2(H.sub.3 NCH.sub.2 CH.sub.2).sub.3 N.6(H.sub.2 O) is dispersed in the liquid mixture, selectively intercalating one or more compounds into the crystalline structure of the Mn.sub.3 (PO.sub.4).sub.4.2(H.sub.3 NCH.sub.2 CH.sub.2).sub.3 N.6(H.sub.2 O).

  6. Carney Complex (United States)

    ... at least one of the features listed. Major diagnostic features for Carney Complex Spotty skin pigmentation with ... called large cell calcifying Sertoli cell tumor (LCCST) Thyroid cancer Psammomatous melanotic schwannoma, meaning tumors that grow on ...

  7. Complex Covariance

    Directory of Open Access Journals (Sweden)

    Frieder Kleefeld


    Full Text Available According to some generalized correspondence principle the classical limit of a non-Hermitian quantum theory describing quantum degrees of freedom is expected to be the well known classical mechanics of classical degrees of freedom in the complex phase space, i.e., some phase space spanned by complex-valued space and momentum coordinates. As special relativity was developed by Einstein merely for real-valued space-time and four-momentum, we will try to understand how special relativity and covariance can be extended to complex-valued space-time and four-momentum. Our considerations will lead us not only to some unconventional derivation of Lorentz transformations for complex-valued velocities, but also to the non-Hermitian Klein-Gordon and Dirac equations, which are to lay the foundations of a non-Hermitian quantum theory.

  8. Improved single-channel speech separation using sinusoidal modeling

    DEFF Research Database (Denmark)

    Mowlaee, Pejman; Christensen, Mads Græsbøll; Jensen, Søren Holdt


    We present a novel single-channel separation approach to improve the separation performance while recovering the signals from a mixture. The key idea in this research is to employ a mixture estimator based on unconstrained modified sinusoidal parameters. Compared to the mixmax (binary mask......) and Wiener filter (softmask) approaches, the proposed approach works independently of pitch estimates. Furthermore, it is observed that it can achieve acceptable perceptual speech quality with less cross-talk at different signal-tosignal ratios while bringing down the complexity by replacing STFT...

  9. New Results on Single-Channel Speech Separation Using Sinusoidal Modeling

    DEFF Research Database (Denmark)

    Mowlaee, Pejman; Christensen, Mads Græsbøll; Jensen, Søren Holdt


    We present new results on single-channel speech separation and suggest a new separation approach to improve the speech quality of separated signals from an observed mix- ture. The key idea is to derive a mixture estimator based on sinusoidal parameters. The proposed estimator is aimed at finding...... complexity of the separation by replacing the short-time Fourier transform (STFT) feature vectors of high dimensionality with sinusoidal feature vectors. We report separation results for the proposed method and compare them with respect to other benchmark methods. The improvements made by applying...

  10. CO{sub 2} separation

    Energy Technology Data Exchange (ETDEWEB)

    Hakuta, Toshikatu [National Inst. of Materials and Chemical Research, Ibaraki (Japan)


    The climate change induced by CO{sub 2} and other greenhouse gases is probably the most serious environmental threat that mankind has ever experienced. Nowadays fossil fuels occupy the majority of the world commercial energy supply. Most nations will be dependent on fossil fuels even in the first half of the next century. Around 30 % of CO{sub 2} in the world is emitted from thermal power plants. Recovering CO{sub 2} from energy conversion processes and storing it outside the atmosphere is a promising option for the mitigation of global warming. CO{sub 2} fixation and storage include CO{sub 2} disposal into oceans and underground, and utilization of CO{sub 2}. CO{sub 2} separation process will be used in any CO{sub 2} storage system, and is estimated to consume almost half the energy of the total system. Research and development of highly efficient CO{sub 2} separation process is most important from the viewpoint of practical application of CO{sub 2} fixation system.

  11. Cell separation using electric fields (United States)

    Mangano, Joseph (Inventor); Eppich, Henry (Inventor)


    The present invention involves methods and devices which enable discrete objects having a conducting inner core, surrounded by a dielectric membrane to be selectively inactivated by electric fields via irreversible breakdown of their dielectric membrane. One important application of the invention is in the selection, purification, and/or purging of desired or undesired biological cells from cell suspensions. According to the invention, electric fields can be utilized to selectively inactivate and render non-viable particular subpopulations of cells in a suspension, while not adversely affecting other desired subpopulations. According to the inventive methods, the cells can be selected on the basis of intrinsic or induced differences in a characteristic electroporation threshold, which can depend, for example, on a difference in cell size and/or critical dielectric membrane breakdown voltage. The invention enables effective cell separation without the need to employ undesirable exogenous agents, such as toxins or antibodies. The inventive method also enables relatively rapid cell separation involving a relatively low degree of trauma or modification to the selected, desired cells. The inventive method has a variety of potential applications in clinical medicine, research, etc., with two of the more important foreseeable applications being stem cell enrichment/isolation, and cancer cell purging.

  12. Membrane separation system and process

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, M.J.; Smolarek, J.: Van Lente, T.S.


    This patent describes an improved air separation process. It comprises compressing a feed air stream containing condensible water vapor to a desired feed air pressure; cooling the compressed feed air stream to below the design operating temperature level of the air separation process, thereby supersaturating the feed air so that the feed air stream comprises feed air saturated with condensible water vapor together with free water droplets; removing the free water droplets from the feed air stream; passing the compressed, cooled feed air stream, free of water droplets, into an insulated enclosure adapted to control and/or minimize the lose of heat therefrom, without superheat of the feed air stream prior to its passage into the insulated enclosure and without predrying the feed air stream to a temperature dew point lower than the design operating temperature prior to the passage of the feed air stream into the insulated enclosure; supplying sufficient heat within the insulated enclosure so as to superheat the feed air stream therein to a temperature where the saturation temperature thereof at the feed air pressure.

  13. The role of carboxylic acids in TALSQueak separations

    Energy Technology Data Exchange (ETDEWEB)

    Braley, Jenifer C.; Carter, Jennifer C.; Sinkov, Sergey I.; Nash, Ken L.; Lumetta, Gregg J.


    Recent reports have indicated TALSPEAK-type separations chemistry can be improved through the replacement of bis-2-ethyl(hexyl) phosphoric acid (HDEHP) and diethylenetriamine-N,N,N,N,N-pentaacetic acid (DTPA) with the weaker reagents 2-ethyl(hexyl) phosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) and N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), respectively. This modified TALSPEAK has been provided with an adjusted acronym of TALSQueak (Trivalent Actinide Lanthanide Separation using Quicker Extractants and Aqueous Komplexes). Among several benefits, TALSQueak chemistry provides more rapid phase transfer kinetics, is less reliant on carboxylic acids to mediate lanthanide extraction and allows a simplified thermodynamic description of the separations process that generally requires only parameters available in the literature to describe metal transfer. This manuscript focuses on the role of carboxylic acids in aqueous ternary (M-HEDTA-carboxylate) complexes, americium/lanthanide separations, and extraction kinetics. Spectrophotometry (UV-vis) of the Nd hypersensitive band indicates the presence of aqueous ternary species (K111 = 1.83 {+-} 0.01 at 1.0 M ionic strength, Nd(HEDTA) + Lac <-> Nd(HEDTA)Lac). Varying the carboxylic acid does not have a significant impact on Ln/Am separations or extraction kinetics. TALSqueak separations come to equilibrium in five minutes at the conventional operational pH of 3.6 using only 0.1 M total lactate or citrate.

  14. Improving Separation Assurance Stability Through Trajectory Flexibility Preservation (United States)

    Idris, Husni; Shen, Ni; Wing, David J.


    New information and automation technologies are enabling the distribution of tasks and decisions from the service providers to the users of the air traffic system, with potential capacity and cost benefits. This distribution of tasks and decisions raises the concern that independent user actions will decrease the predictability and increase the complexity of the traffic system, hence inhibiting and possibly reversing any potential benefits. One such concern is the adverse impact of uncoordinated actions by individual aircraft on the stability of separation assurance. For example, individual aircraft performing self-separation may resolve predicted losses of separation or conflicts with some traffic, only to result in secondary conflicts with other traffic or with the same traffic later in time. In answer to this concern, this paper proposes metrics for preserving user trajectory flexibility to be used in self-separation along with other objectives. The hypothesis is that preserving trajectory flexibility will naturally reduce the creation of secondary conflicts by bringing about implicit coordination between aircraft. The impact of using these metrics on improving self-separation stability is investigated by measuring the impact on secondary conflicts. The scenarios analyzed include aircraft in en route airspace with each aircraft meeting a required time of arrival in a twenty minute time horizon while maintaining separation from the surrounding traffic and using trajectory flexibility metrics to mitigate the risk of secondary conflicts. Preliminary experiments showed promising results in that the trajectory flexibility preservation reduced the potential for secondary conflicts.

  15. Numerical investigation of flow separation behavior in an over-expanded annular conical aerospike nozzle

    Directory of Open Access Journals (Sweden)

    He Miaosheng


    Full Text Available A three-part numerical investigation has been conducted in order to identify the flow separation behavior—the progression of the shock structure, the flow separation pattern with an increase in the nozzle pressure ratio (NPR, the prediction of the separation data on the nozzle wall, and the influence of the gas density effect on the flow separation behavior are included. The computational results reveal that the annular conical aerospike nozzle is dominated by shock/shock and shock/boundary layer interactions at all calculated NPRs, and the shock physics and associated flow separation behavior are quite complex. An abnormal flow separation behavior as well as a transition process from no flow separation at highly over-expanded conditions to a restricted shock separation and finally to a free shock separation even at the deign condition can be observed. The complex shock physics has further influence on the separation data on both the spike and cowl walls, and separation criteria suggested by literatures developed from separation data in conical or bell-type rocket nozzles fail at the prediction of flow separation behavior in the present asymmetric supersonic nozzle. Correlation of flow separation with the gas density is distinct for highly over-expanded conditions. Decreasing the gas density or reducing mass flow results in a smaller adverse pressure gradient across the separation shock or a weaker shock system, and this is strongly coupled with the flow separation behavior. The computational results agree well with the experimental data in both shock physics and static wall pressure distribution at the specific NPRs, indicating that the computational methodology here is advisable to accurately predict the flow physics.

  16. Polystochastic Models for Complexity

    CERN Document Server

    Iordache, Octavian


    This book is devoted to complexity understanding and management, considered as the main source of efficiency and prosperity for the next decades. Divided into six chapters, the book begins with a presentation of basic concepts as complexity, emergence and closure. The second chapter looks to methods and introduces polystochastic models, the wave equation, possibilities and entropy. The third chapter focusing on physical and chemical systems analyzes flow-sheet synthesis, cyclic operations of separation, drug delivery systems and entropy production. Biomimetic systems represent the main objective of the fourth chapter. Case studies refer to bio-inspired calculation methods, to the role of artificial genetic codes, neural networks and neural codes for evolutionary calculus and for evolvable circuits as biomimetic devices. The fifth chapter, taking its inspiration from systems sciences and cognitive sciences looks to engineering design, case base reasoning methods, failure analysis, and multi-agent manufacturing...

  17. Determination of metal ions by high-performance liquid chromatographic separation of their hydroxamic acid chelates

    Energy Technology Data Exchange (ETDEWEB)

    Palmieri, M.D.; Fritz, J.S.


    Metal ions are determined by adding N-methylfurohydroxamic acid to an aqueous sample and then separating the metal chelates by direct injection onto a liquid chromatographic column. Separations on a C/sub 8/ silica column and a polystyrene-divinylbenzene column are compared, with better separations seen on the polymeric column. The complexes formed at low pH values are cationic and are separated by an ion pairing mechanism. Retention times and selectivity of the metal complexes can be varied by changing the pH. Several metal ions can be separated and quantified; separation conditions, linear calibration curve ranges, and detection limits are presented for Zr(IV), Hf(IV), Fe(III), Nb(V), Al(III), and Sb(III). Interferences due to the presence of other ions in solution are investigated. Finally, an antiperspirant sample is analyzed for zirconium by high-performance liquid chromatography.

  18. Melting, solidification, remelting, and separation of glass and metal

    Energy Technology Data Exchange (ETDEWEB)

    Ebadian, M.A.; Xin, R.C.; Liu, Y.Z.


    Several high-temperature vitrification technologies have been developed for the treatment of a wide range of mixed waste types in both the low-level waste and transuranic (TRU) mixed waste categories currently in storage at DOE sites throughout the nation. The products of these processes are an oxide slag phase and a reduced metal phase. The metal phase has the potential to be recycled within the DOE Complex. Enhanced slag/metal separation methods are needed to support these processes. This research project involves an experimental investigation of the melting, solidification, remelting, and separation of glass and metal and the development of an efficient separation technology. The ultimate goal of this project is to find an efficient way to separate the slag phase from the metal phase in the molten state. This two-year project commenced in October 1995 (FY96). In the first fiscal year, the following tasks were accomplished: (1) A literature review and an assessment of the baseline glass and metal separation technologies were performed. The results indicated that the baseline technology yields a high percentage of glass in the metal phase, requiring further separation. (2) The main melting and solidification system setup was established. A number of melting and solidification tests were conducted. (3) Temperature distribution, solidification patterns, and flow field in the molten metal pool were simulated numerically for the solidification processes of molten aluminum and iron steel. (4) Initial designs of the laboratory-scale DCS and CS technologies were also completed. The principal demonstration separation units were constructed. (5) An application for a patent for an innovative liquid-liquid separation technology was submitted and is pending.


    Overholser, L.B.; Barton, C.J. Sr.; Ramsey, J.W.


    The separation of hafnium impurities from zirconium can be accomplished by means of organic solvent extraction. The hafnium-containing zirconium feed material is dissolved in an aqueous chloride solution and the resulting solution is contacted with an organic hexone phase, with at least one of the phases containing thiocyanate. The hafnium is extracted into the organic phase while zirconium remains in the aqueous phase. Further recovery of zirconium is effected by stripping the onganic phase with a hydrochloric acid solution and commingling the resulting strip solution with the aqueous feed solution. Hexone is recovered and recycled by means of scrubbing the onganic phase with a sulfuric acid solution to remove the hafnium, and thiocyanate is recovered and recycled by means of neutralizing the effluent streams to obtain ammonium thiocyanate.

  20. SOFC and Gas Separation Membranes

    DEFF Research Database (Denmark)

    Hagen, Anke; Hendriksen, Peter Vang; Søgaard, Martin


    , increase the efficiency of power production processes from fossil fuels and also to consider carbon capture and sequestration (CCS). Solid oxide fuel cells (SOFCs) convert the chemical energy bound in a fuel directly into electrical energy at temperatures ranging from 600 to 1000 oC, depending...... as SOFCs. Such membranes can potentially be used in Oxyfuel processes as well as in IGCC (Integrated Gasification Combined Cycle) power plants for supply of process oxygen, which may reduce cost of carbon capture and storage as dilution of the flue gas with nitrogen is avoided. Both technologies are very...... on the materials used in the SOFCs. Due to the high efficiencies, the amount of CO2 emitted from carbon containing fuels is smaller compared to conventional energy production technologies based on fuel combustion. Furthermore, CO2 is formed at the anode side of the fuel cell together with steam, and thus separated...

  1. Complex chimerism (United States)

    Ma, Kimberly K.; Petroff, Margaret G.; Coscia, Lisa A.; Armenti, Vincent T.; Adams Waldorf, Kristina M.


    Thousands of women with organ transplantation have undergone successful pregnancies, however little is known about how the profound immunologic changes associated with pregnancy might influence tolerance or rejection of the allograft. Pregnant women with a solid organ transplant are complex chimeras with multiple foreign cell populations from the donor organ, fetus, and mother of the pregnant woman. We consider the impact of complex chimerism and pregnancy-associated immunologic changes on tolerance of the allograft both during pregnancy and the postpartum period. Mechanisms of allograft tolerance are likely dynamic during pregnancy and affected by the influx of fetal microchimeric cells, HLA relationships (between the fetus, pregnant woman and/or donor), peripheral T cell tolerance to fetal cells, and fetal minor histocompatibility antigens. Further research is necessary to understand the complex immunology during pregnancy and the postpartum period of women with a solid organ transplant. PMID:23974274

  2. Complex analysis

    CERN Document Server

    Freitag, Eberhard


    The guiding principle of this presentation of ``Classical Complex Analysis'' is to proceed as quickly as possible to the central results while using a small number of notions and concepts from other fields. Thus the prerequisites for understanding this book are minimal; only elementary facts of calculus and algebra are required. The first four chapters cover the essential core of complex analysis: - differentiation in C (including elementary facts about conformal mappings) - integration in C (including complex line integrals, Cauchy's Integral Theorem, and the Integral Formulas) - sequences and series of analytic functions, (isolated) singularities, Laurent series, calculus of residues - construction of analytic functions: the gamma function, Weierstrass' Factorization Theorem, Mittag-Leffler Partial Fraction Decomposition, and -as a particular highlight- the Riemann Mapping Theorem, which characterizes the simply connected domains in C. Further topics included are: - the theory of elliptic functions based on...

  3. Complex manifolds

    CERN Document Server

    Morrow, James


    This book, a revision and organization of lectures given by Kodaira at Stanford University in 1965-66, is an excellent, well-written introduction to the study of abstract complex (analytic) manifolds-a subject that began in the late 1940's and early 1950's. It is largely self-contained, except for some standard results about elliptic partial differential equations, for which complete references are given. -D. C. Spencer, MathSciNet The book under review is the faithful reprint of the original edition of one of the most influential textbooks in modern complex analysis and geometry. The classic

  4. Separating conjoined twins: a medical and criminal law dilemma. (United States)

    Davis, Colleen


    Surgical separation of conjoined twins that results in the death of one of the twins raises complex moral, ethical and legal issues. Of particular concern is the potential for homicide charges against doctors. In two recent cases, one in England and one in Queensland, judges declared the surgery to be lawful but the legal reasoning employed is problematical and may be difficult to apply to future conjoined twins cases, such as infant twins where one is not fully developed, or where it is proposed to separate adult twins. A determination of the threshold issue of whether there are two individual persons capable of being killed may require a reconsideration of existing legal definitions and statutory provisions. Similarly, the excuses and justifications for homicide may need to be clarified or reviewed in the context of separation of conjoined twins.

  5. Pretreatment/Radionuclide Separations of Cs/Tc from Supernates

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, M.C. [Westinghouse Savannah River Company, AIKEN, SC (United States)


    Significant improvements have been made in ion exchange and solvent extraction materials and processes available for separation of the radionuclides cesium and technetium from both acid and alkaline waste solutions. New ion exchange materials and solvent extraction reagents are more selective for Cs over sodium and potassium than previous materials. The higher selectivity gives higher Cs capacity and improved separation processes. Technetium removal has been improved by new ion exchange resins, which have either improved capacity or easier elution. Several different crown ethers have been shown to extract pertechnetate ion selectively over other anions. Organic complexants in some waste solutions reduce pertechnetate ion and stabilize the reduced species. Selective oxidation allows conversion to pertechnetate without oxidation of the organic complexants.

  6. Platinum metals-solution chemistry and separation methods (ion-exchange and solvent extraction)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Bazi, S.J.; Chow, A. (Manitoba Univ., Winnipeg (Canada). Dept. of Chemistry)


    The effects of knowledge of the solution chemistry of the platinum metals on their separation by solvent extraction and ion-exchange methods are reviewed, for the period 1950 to 1983. The review concentrates on the chloro-complexes of these metals and indicates those areas which need more investigation or interpretation to provide adequate separational methods.

  7. Managing Complexity

    DEFF Research Database (Denmark)

    Maylath, Bruce; Vandepitte, Sonia; Minacori, Patricia


    This article discusses the largest and most complex international learning-by-doing project to date- a project involving translation from Danish and Dutch into English and editing into American English alongside a project involving writing, usability testing, and translation from English into Dutch...

  8. phenanthroline complexes

    Indian Academy of Sciences (India)

    structural analyses. Mass spectral studies of the complexes indicate both the compounds to produce identical cationic species viz., [Co(phen)2Cl2]+ in methanol solution. ... Cobalt(III); X-ray structure; Catecholase activity; DNA cleavage; Anti-cancer activity. 1. ..... necrotic as judged by the staining, nuclear morphology.

  9. Lecithin Complex

    African Journals Online (AJOL)

    China). Lecithin from soya bean was a product of. Sangon (Shanghai, China). Methanol of HPLC grade was purchased from Tedia (USA). Other chemicals used were of analytical grade. Preparation of polydatin-lecithin complex. Polydatin (200 mg) and lecithin (400 mg) were dissolved in 50 mL of tetrahydrofuran and stirred.

  10. Complex Criminality

    NARCIS (Netherlands)

    Bruin, D.; Abels, D.; van der Wilt, H.


    This book presents a collection of essays on the wide diversity of meanings of complex criminality. These essays were written to commemorate a national gathering of PhD candidates, from criminal law departments of different universities, at the University of Amsterdam on the 6th of June 2014.

  11. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta


    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  12. peroxo complexes

    Indian Academy of Sciences (India)


    The investigation of dioxygen binding and activation in dinuclear iron complexes has attracted recent interest because of the presence of carboxylate bridged dinuclear iron sites in several biologically important proteins, such as the R2 protein of ribonucleotide reductase, the hydroxylase component of methane ...

  13. carbohydrate complexes

    Indian Academy of Sciences (India)

    ferrocene-carbohydrate conjugates38,39 have lead to the design and study of the cytotoxic activity of metal com- plexes containing carbohydrate ligands. Hence, here we present the detailed synthesis and characteriza- tion of the carbohydrate triazole ligands and their Pd- complexes together with the crystal structures of ...

  14. Ntem Complex

    African Journals Online (AJOL)


    New ages were obtained from charnockites and tonalites collected in the So'o Group in the Ntem Complex. The rocks were analyzed for their petrography, tectonics and 207Pb/206Pb zircon minimum ages of their zircons as well as .... Owona, Department of Earth Sciences, Faculty of Science, University of Douala, P.O. Box.

  15. What`s Wrong with Primary Separators?

    Energy Technology Data Exchange (ETDEWEB)

    Nilsen, F.P.; Davies, G.A.


    Primary separators are used to separate multiphase mixtures to produce bulk flows of gas/oil/water and to remove separate solids. This paper reviews the main process design criteria used in present design practice. The separators rely on gravity separation of the various phases. The mixtures to be separated do not always form readily separable systems, which can lead to malfunction, cross-entrainment and poor separation quality. Recent design methodologies are reviewed with a focus on reduced cross-entrainment and increased capacity (separation fluxes). Various equipment designs are discussed and an approach to system design is presented. When a primary separator is designed, it is essential that a full process specification and characterization data for the process fluids are available. It is important to select and design an effective inlet distributor accounting for the expected structure of the inlet flow. The use of internals to promote separation of gas/liquid and liquid/liquid mixtures are essential if maximum separation rates are to be achieved. Finally, a careful review of the use of chemicals must be carried out particularly with regard to the type, concentration and position of introduction. The paper was presented at The 3rd Major Conference on Current Developments in Production Separation Systems, 23 and 24 April 1996. 2 refs., 14 figs., 1 table

  16. Optimization via separated representations and the canonical tensor decomposition (United States)

    Reynolds, Matthew J.; Beylkin, Gregory; Doostan, Alireza


    We introduce a new, quadratically convergent algorithm for finding maximum absolute value entries of tensors represented in the canonical format. The computational complexity of the algorithm is linear in the dimension of the tensor. We show how to use this algorithm to find global maxima of non-convex multivariate functions in separated form. We demonstrate the performance of the new algorithms on several examples.

  17. Bregman Clustering for Separable Instances (United States)

    Ackermann, Marcel R.; Blömer, Johannes

    The Bregman k-median problem is defined as follows. Given a Bregman divergence D φ and a finite set P subseteq { R}^d of size n, our goal is to find a set C of size k such that the sum of errors cost(P,C) = ∑ p ∈ P min c ∈ C D φ (p,c) is minimized. The Bregman k-median problem plays an important role in many applications, e.g., information theory, statistics, text classification, and speech processing. We study a generalization of the kmeans++ seeding of Arthur and Vassilvitskii (SODA '07). We prove for an almost arbitrary Bregman divergence that if the input set consists of k well separated clusters, then with probability 2^{-{O}(k)} this seeding step alone finds an {O}(1)-approximate solution. Thereby, we generalize an earlier result of Ostrovsky et al. (FOCS '06) from the case of the Euclidean k-means problem to the Bregman k-median problem. Additionally, this result leads to a constant factor approximation algorithm for the Bregman k-median problem using at most 2^{{O}(k)}n arithmetic operations, including evaluations of Bregman divergence D φ .

  18. Accuracy assessment with complex sampling designs (United States)

    Raymond L. Czaplewski


    A reliable accuracy assessment of remotely sensed geospatial data requires a sufficiently large probability sample of expensive reference data. Complex sampling designs reduce cost or increase precision, especially with regional, continental and global projects. The General Restriction (GR) Estimator and the Recursive Restriction (RR) Estimator separate a complex...

  19. Separation and quantification of microalgal carbohydrates. (United States)

    Templeton, David W; Quinn, Matthew; Van Wychen, Stefanie; Hyman, Deborah; Laurens, Lieve M L


    Structural carbohydrates can constitute a large fraction of the dry weight of algal biomass and thus accurate identification and quantification is important for summative mass closure. Two limitations to the accurate characterization of microalgal carbohydrates are the lack of a robust analytical procedure to hydrolyze polymeric carbohydrates to their respective monomers and the subsequent identification and quantification of those monosaccharides. We address the second limitation, chromatographic separation of monosaccharides, here by identifying optimum conditions for the resolution of a synthetic mixture of 13 microalgae-specific monosaccharides, comprised of 8 neutral, 2 amino sugars, 2 uronic acids and 1 alditol (myo-inositol as an internal standard). The synthetic 13-carbohydrate mix showed incomplete resolution across 11 traditional high performance liquid chromatography (HPLC) methods, but showed improved resolution and accurate quantification using anion exchange chromatography (HPAEC) as well as alditol acetate derivatization followed by gas chromatography (for the neutral- and amino-sugars only). We demonstrate the application of monosaccharide quantification using optimized chromatography conditions after sulfuric acid analytical hydrolysis for three model algae strains and compare the quantification and complexity of monosaccharides in analytical hydrolysates relative to a typical terrestrial feedstock, sugarcane bagasse. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Isogeometric shape optimization of magnetic density separators

    NARCIS (Netherlands)

    Dang Manh, N.; Evgrafov, A.; Gravesen, J.; Lahaye, D.


    Purpose: The waste recycling industry increasingly relies on magnetic density separators. These devices generate an upward magnetic force in ferro-fluids allowing to separate the immersed particles according to their mass density. Recently a new separator design that significantly reduces the

  1. FCC riser quick separation system: a review

    Directory of Open Access Journals (Sweden)

    Zhi Li


    Full Text Available Abstract The riser reactor is the key unit in the fluid catalytic cracking (FCC process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future.

  2. Atomic lithium vapor laser isotope separation

    CERN Document Server

    Olivares, I E


    An atomic vapor laser isotope separation in lithium was performed using tunable diode lasers. The method permits also the separation of the isotopes between the sup 6 LiD sub 2 and the sup 7 LiD sub 1 lines using a self-made mass separator which includes a magnetic sector and an ion beam designed for lithium. (Author)

  3. Absolutely separating quantum maps and channels (United States)

    Filippov, S. N.; Magadov, K. Yu; Jivulescu, M. A.


    Absolutely separable states ϱ remain separable under arbitrary unitary transformations U\\varrho {U}\\dagger . By example of a three qubit system we show that in a multipartite scenario neither full separability implies bipartite absolute separability nor the reverse statement holds. The main goal of the paper is to analyze quantum maps resulting in absolutely separable output states. Such absolutely separating maps affect the states in a way, when no Hamiltonian dynamics can make them entangled afterwards. We study the general properties of absolutely separating maps and channels with respect to bipartitions and multipartitions and show that absolutely separating maps are not necessarily entanglement breaking. We examine the stability of absolutely separating maps under a tensor product and show that {{{Φ }}}\\otimes N is absolutely separating for any N if and only if Φ is the tracing map. Particular results are obtained for families of local unital multiqubit channels, global generalized Pauli channels, and combination of identity, transposition, and tracing maps acting on states of arbitrary dimension. We also study the interplay between local and global noise components in absolutely separating bipartite depolarizing maps and discuss the input states with high resistance to absolute separability.


    Directory of Open Access Journals (Sweden)

    Emilian CIONGARU


    Full Text Available The principle of ensuring the legal bases of the State functioning is the fundamental principle of law which actually settles down the principle of separation of powers: legislative, executive and judicial power. Over the time, the principle of separation of powers, although in practice its enforcement experienced more than two centuries, it hasn’t expressed itself in a pure form, not even in the most advanced democracies. Whether it is approached the thesis of a more flexible or more rigid separation of powers or the thesis on certain exceptions to those two situations specific to certain political regimes, the principle of separation of powers is the fundamental mechanism in ensuring a balance of powers and preventing the establishment of a dictatorial or authoritarian regime. The complex content of the rule of law consists of: the rule of law regency; the capitalization on the actual size of the fundamental rights and freedoms; the achievement of the balance/mutual cooperation of public authorities and the performance of free access to justice. If the form of State organization of the political power of the people is done by several groups or categories of State bodies with functions and features clearly defined and characterized by organizational and functional autonomy, as well as mutual balance and collaboration, it is emerging the principle of separation of the State powers balance.

  5. Efficient Separations and Processing Crosscutting Program. Technology summary

    Energy Technology Data Exchange (ETDEWEB)



    The Efficient Separations and Processing (ESP) Crosscutting Program was created in 1991 to identify, develop, and perfect separations technologies and processes to treat wastes and address environmental problems throughout the DOE Complex. The ESP funds several multi-year tasks that address high-priority waste remediation problems involving high-level, low-level, transuranic, hazardous, and mixed (radioactive and hazardous) wastes. The ESP supports applied research and development (R and D) leading to demonstration or use of these separations technologies by other organizations within DOE-EM. Treating essentially all DOE defense wastes requires separation methods that concentrate the contaminants and/or purify waste streams for release to the environment or for downgrading to a waste form less difficult and expensive to dispose of. Initially, ESP R and D efforts focused on treatment of high-level waste (HLW) from underground storage tanks (USTs) because of the potential for large reductions in disposal costs and hazards. As further separations needs emerge and as waste management and environmental restoration priorities change, the program has evolved to encompass the breadth of waste management and environmental remediation problems.

  6. Ares I Stage Separation System Design Certification Testing (United States)

    Mayers, Stephen L.; Beard, Bernard B.; Smith, R. Kenneth; Patterson, Alan


    NASA is committed to the development of a new crew launch vehicle, the Ares I, that can support human missions to low Earth orbit (LEO) and the moon with unprecedented safety and reliability. NASA's Constellation program comprises the Ares I and Ares V launch vehicles, the Orion crew vehicle, and the Altair lunar lander. Based on historical precedent, stage separation is one of the most significant technical and systems engineering challenges that must be addressed in order to achieve this commitment. This paper surveys historical separation system tests that have been completed in order to ensure staging of other launch vehicles. Key separation system design trades evaluated for Ares I include single vs. dual separation plane options, retro-rockets vs. pneumatic gas actuators, small solid motor quantity/placement/timing, and continuous vs. clamshell interstage configuration options. Both subscale and full-scale tests are required to address the prediction of complex dynamic loading scenarios present during staging events. Test objectives such as separation system functionality, and pyroshock and debris field measurements for the full-scale tests are described. Discussion about the test article, support infrastructure and instrumentation are provided.

  7. Dynamical phase separation using a microfluidic device: experiments and modeling (United States)

    Aymard, Benjamin; Vaes, Urbain; Radhakrishnan, Anand; Pradas, Marc; Gavriilidis, Asterios; Kalliadasis, Serafim; Complex Multiscale Systems Team


    We study the dynamical phase separation of a binary fluid by a microfluidic device both from the experimental and from the modeling points of view. The experimental device consists of a main channel (600 μm wide) leading into an array of 276 trapezoidal capillaries of 5 μm width arranged on both sides and separating the lateral channels from the main channel. Due to geometrical effects as well as wetting properties of the substrate, and under well chosen pressure boundary conditions, a multiphase flow introduced into the main channel gets separated at the capillaries. Understanding this dynamics via modeling and numerical simulation is a crucial step in designing future efficient micro-separators. We propose a diffuse-interface model, based on the classical Cahn-Hilliard-Navier-Stokes system, with a new nonlinear mobility and new wetting boundary conditions. We also propose a novel numerical method using a finite-element approach, together with an adaptive mesh refinement strategy. The complex geometry is captured using the same computer-aided design files as the ones adopted in the fabrication of the actual device. Numerical simulations reveal a very good qualitative agreement between model and experiments, demonstrating also a clear separation of phases.

  8. Cation-enhanced capillary electrophoresis separation of atropoisomer anions. (United States)

    Na, Yun-Cheol; Berthod, Alain; Armstrong, Daniel W


    CE was used to study the separation of the atropoisomers of four phosphoric acids and two sulfonic acids and the enantiomers of two phosphoric acids. All solutes are in their anionic forms in aqueous electrolytes. The chiral additives were two hydroxypropyl cyclodextrins (CDs) and cyclofructan 6 (CF6). The CDs were able to separate four solutes and the CF6 additive could separate only one: 1,1'-binaphthyl-2,2'-diyl hydrogenphosphate (BHP). Since CF6 is able to bind with cations, nitrate of alkaline metals, Ba(2+) , and Pb(2+) were added, greatly improving the BHP separation at the expense of longer migration times. There seems to be a link between CF6-cation-binding constants and BHP resolution factors. Cation additions were also performed with CD selectors that are less prone to form complexes with cations. Significant improvements of enantiomer or atropoisomer separations were observed also associated with longer migration times. It is speculated that the anionic solutes associate with the added cations forming larger entities better differentiated by CDs. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Managing Complexity

    Energy Technology Data Exchange (ETDEWEB)

    Chassin, David P.; Posse, Christian; Malard, Joel M.


    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  10. Complex Questions Promote Complex Thinking (United States)

    Degener, Sophie; Berne, Jennifer


    Intermediate-grade teachers often express concerns about meeting the Common Core State Standards for Reading, primarily because of the emphasis on deep understanding of complex texts. No matter how difficult the text, if teachers demand little of the reading, student meaning making is not challenged. This article offers a tool for teachers to…

  11. Supercritical fluid reverse micelle separation (United States)

    Fulton, J.L.; Smith, R.D.


    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W[sub o] that determines the maximum size of the reverse micelles. The maximum ratio W[sub o] of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions. 27 figures.

  12. Separate spheres and indirect benefits

    Directory of Open Access Journals (Sweden)

    Brock Dan W


    Full Text Available Abstract On any plausible account of the basis for health care resource prioritization, the benefits and costs of different alternative resource uses are relevant considerations in the prioritization process. Consequentialists hold that the maximization of benefits with available resources is the only relevant consideration. Non-consequentialists do not reject the relevance of consequences of benefits and costs, but insist that other considerations, and in particular the distribution of benefits and costs, are morally important as well. Whatever one's particular account of morally justified standards for the prioritization of different health interventions, we must be able to measure those interventions' benefits and costs. There are many theoretical and practical difficulties in that measurement, such as how to weigh extending life against improving health and quality of life as well as how different quality of life improvements should be valued, but they are not my concern here. This paper addresses two related issues in assessing benefits and costs for health resource prioritization. First, should benefits be restricted only to health benefits, or include as well other non health benefits such as economic benefits to employers from reducing the lost work time due to illness of their employees? I shall call this the Separate Spheres problem. Second, should only the direct benefits, such as extending life or reducing disability, and direct costs, such as costs of medical personnel and supplies, of health interventions be counted, or should other indirect benefits and costs be counted as well? I shall call this the Indirect Benefits problem. These two issues can have great importance for a ranking of different health interventions by either a cost/benefit or cost effectiveness analysis (CEA standard.

  13. Complex Macrophase-Separated Nanostructure Induced by Microphase Separation in Binary Blends of Lamellar Diblock Copolymer Thin Films

    DEFF Research Database (Denmark)

    Zhang, Jianqi; Posselt, Dorthe; Smilgies, Detlef-M.


    The nanostructures of thin films spin-coated from binary blends of compositionally symmetric polystyrene-b-polybutadiene (PS-b-PB) diblock copolymer having different molar masses are investigated by means of atomic force microscopy (AFM) and grazing-incidence small-angle X-ray scattering (GISAXS)...

  14. Centrifugal separator devices, systems and related methods (United States)

    Meikrantz, David H [Idaho Falls, ID; Law, Jack D [Pocatello, ID; Garn, Troy G [Idaho Falls, ID; Todd, Terry A [Aberdeen, ID; Macaluso, Lawrence L [Carson City, NV


    Centrifugal separator devices, systems and related methods are described. More particularly, fluid transfer connections for a centrifugal separator system having support assemblies with a movable member coupled to a connection tube and coupled to a fixed member, such that the movable member is constrained to movement along a fixed path relative to the fixed member are described. Also, centrifugal separator systems including such fluid transfer connections are described. Additionally, methods of installing, removing and/or replacing centrifugal separators from centrifugal separator systems are described.

  15. Conventional and Advanced Separations in Mass Spectrometry-Based Metabolomics: Methodologies and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Heyman, Heino M.; Zhang, Xing; Tang, Keqi; Baker, Erin Shammel; Metz, Thomas O.


    Metabolomics is the quantitative analysis of all metabolites in a given sample. Due to the chemical complexity of the metabolome, optimal separations are required for comprehensive identification and quantification of sample constituents. This chapter provides an overview of both conventional and advanced separations methods in practice for reducing the complexity of metabolite extracts delivered to the mass spectrometer detector, and covers gas chromatography (GC), liquid chromatography (LC), capillary electrophoresis (CE), supercritical fluid chromatography (SFC) and ion mobility spectrometry (IMS) separation techniques coupled with mass spectrometry (MS) as both uni-dimensional and as multi-dimensional approaches.

  16. Innovative SANEX process for trivalent actinides separation from PUREX raffinate

    Energy Technology Data Exchange (ETDEWEB)

    Sypula, Michal


    Recycling of nuclear spent fuel and reduction of its radiotoxicity by separation of long-lived radionuclides would definitely help to close the nuclear fuel cycle ensuring sustainability of the nuclear energy. Partitioning of the main radiotoxicity contributors followed by their conversion into short-lived radioisotopes is known as partitioning and transmutation strategy. To ensure efficient transmutation of the separated elements (minor actinides) the content of lanthanides in the irradiation targets has to be minimised. This objective can be attained by solvent extraction using highly selective ligands that are able to separate these two groups of elements from each other. The objective of this study was to develop a novel process allowing co-separation of minor actinides and lanthanides from a high active acidic feed solution with subsequent actinide recovery using just one cycle, so-called innovative SANEX process. The conditions of each step of the process were optimised to ensure high actinide separation efficiency. Additionally, screening tests of several novel lipophilic and hydrophilic ligands provided by University of Twente were performed. These tests were aiming in better understanding the influence of the extractant structural modifications onto An(III)/Ln(III) selectivity and complexation properties. Optimal conditions for minor actinides separation were found and a flow-sheet of a new innovative SANEX process was proposed. Tests using a single centrifugal contactor confirmed high Eu(III)/Am(III) separation factor of 15 while the lowest SF{sub Ln/Am} obtained was 6,5 (for neodymium). In addition, a new masking agent for zirconium was found as a substitution for oxalic acid. This new masking agent (CDTA) was also able to mask palladium without any negative influence on An(III)/Ln(III). Additional tests showed no influence of CDTA on plutonium present in the feed solution unlike oxalic acid which causes Pu precipitation. Therefore, CDTA was proposed as

  17. Key factors of eddy current separation for recovering aluminum from crushed e-waste. (United States)

    Ruan, Jujun; Dong, Lipeng; Zheng, Jie; Zhang, Tao; Huang, Mingzhi; Xu, Zhenming


    Recovery of e-waste in China had caused serious pollutions. Eddy current separation is an environment-friendly technology of separating nonferrous metallic particles from crushed e-waste. However, due to complex particle characters, separation efficiency of traditional eddy current separator was low. In production, controllable operation factors of eddy current separation are feeding speed, (ωR-v), and S p . There is little special information about influencing mechanism and critical parameters of these factors in eddy current separation. This paper provided the special information of these key factors in eddy current separation of recovering aluminum particles from crushed waste refrigerator cabinets. Detachment angles increased as the increase of (ωR-v). Separation efficiency increased with the growing of detachment angles. Aluminum particles were completely separated from plastic particles in critical parameters of feeding speed 0.5m/s and detachment angles greater than 6.61deg. S p /S m of aluminum particles in crushed waste refrigerators ranged from 0.08 to 0.51. Separation efficiency increased as the increase of S p /S m . This enlightened us to develop new separator to separate smaller nonferrous metallic particles in e-waste recovery. High feeding speed destroyed separation efficiency. However, greater S p of aluminum particles brought positive impact on separation efficiency. Greater S p could increase critical feeding speed to offer greater throughput of eddy current separation. This paper will guide eddy current separation in production of recovering nonferrous metals from crushed e-waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Children's separation anxiety scale (CSAS: psychometric properties.

    Directory of Open Access Journals (Sweden)

    Xavier Méndez

    Full Text Available This study describes the psychometric properties of the Children's Separation Anxiety Scale (CSAS, which assesses separation anxiety symptoms in childhood. Participants in Study 1 were 1,908 schoolchildren aged between 8 and 11. Exploratory factor analysis identified four factors: worry about separation, distress from separation, opposition to separation, and calm at separation, which explained 46.91% of the variance. In Study 2, 6,016 children aged 8-11 participated. The factor model in Study 1 was validated by confirmatory factor analysis. The internal consistency (α = 0.82 and temporal stability (r = 0.83 of the instrument were good. The convergent and discriminant validity were evaluated by means of correlations with other measures of separation anxiety, childhood anxiety, depression and anger. Sensitivity of the scale was 85% and its specificity, 95%. The results support the reliability and validity of the CSAS.

  19. [Complex posttraumatic stress disorder]. (United States)

    Green, Tamar; Kotler, Moshe


    The characteristic symptoms resulting from exposure to an extreme trauma include three clusters of symptoms: persistent experience of the traumatic event, persistent avoidance of stimuli associated with the trauma and persistent symptoms of increased arousal. Beyond the accepted clusters of symptoms for posttraumatic stress disorder exists a formation of symptoms related to exposure to extreme or prolonged stress e.g. childhood abuse, physical violence, rape, and confinement within a concentration camp. With accumulated evidence of the existence of these symptoms began a trail to classify a more complex syndrome, which included, but was not confined to the symptoms of posttraumatic stress disorder. This review addresses several subjects for study in complex posttraumatic stress disorder, which is a complicated and controversial topic. Firstly, the concept of complex posttraumatic stress disorder is presented. Secondly, the professional literature relevant to this disturbance is reviewed and finally, the authors present the polemic being conducted between the researchers of posttraumatic disturbances regarding validity, reliability and the need for separate diagnosis for these symptoms.

  20. Separable representation of multichannel nucleon-nucleus optical potentials (United States)

    Hlophe, L.; Elster, Ch.


    Background: One important ingredient for many applications of nuclear physics to astrophysics, nuclear energy, and stockpile stewardship is cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not feasible, indirect methods, e.g., (d ,p ) reactions, should be used. Those (d ,p ) reactions may be viewed as three-body reactions and described with Faddeev techniques. Purpose: Faddeev equations in momentum space have a long tradition of utilizing separable interactions in order to arrive at sets of coupled integral equations in one variable. Optical potentials representing the effective interactions in the neutron (proton) nucleus subsystem are usually non-Hermitian as well as energy dependent. Including excitations of the nucleus in the calculation requires a multichannel optical potential. The purpose of this paper is to introduce a separable, energy-dependent multichannel representation of complex, energy-dependent optical potentials that contain excitations of the nucleus and that fulfill reciprocity exactly. Methods: Momentum space Lippmann-Schwinger integral equations are solved with standard techniques to obtain the form factors for the separable representation. Results: Starting from energy-dependent multichannel optical potentials for neutron and proton scattering from 12C, separable representations based on a generalization of the Ernst-Shakin-Thaler (EST) scheme are constructed which fulfill reciprocity exactly. Applications to n +12C and p +12C scattering are investigated for energies from 0 to 50 MeV. Conclusions: We find that the energy-dependent separable representation of complex, energy-dependent phenomenological multichannel optical potentials describes scattering data with the same quality as the original potential.

  1. Complex variables

    CERN Document Server

    Flanigan, Francis J


    A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion

  2. Complex variables

    CERN Document Server

    Taylor, Joseph L


    The text covers a broad spectrum between basic and advanced complex variables on the one hand and between theoretical and applied or computational material on the other hand. With careful selection of the emphasis put on the various sections, examples, and exercises, the book can be used in a one- or two-semester course for undergraduate mathematics majors, a one-semester course for engineering or physics majors, or a one-semester course for first-year mathematics graduate students. It has been tested in all three settings at the University of Utah. The exposition is clear, concise, and lively

  3. Separating common from distinctive variation. (United States)

    van der Kloet, Frans M; Sebastián-León, Patricia; Conesa, Ana; Smilde, Age K; Westerhuis, Johan A


    Joint and individual variation explained (JIVE), distinct and common simultaneous component analysis (DISCO) and O2-PLS, a two-block (X-Y) latent variable regression method with an integral OSC filter can all be used for the integrated analysis of multiple data sets and decompose them in three terms: a low(er)-rank approximation capturing common variation across data sets, low(er)-rank approximations for structured variation distinctive for each data set, and residual noise. In this paper these three methods are compared with respect to their mathematical properties and their respective ways of defining common and distinctive variation. The methods are all applied on simulated data and mRNA and miRNA data-sets from GlioBlastoma Multiform (GBM) brain tumors to examine their overlap and differences. When the common variation is abundant, all methods are able to find the correct solution. With real data however, complexities in the data are treated differently by the three methods. All three methods have their own approach to estimate common and distinctive variation with their specific strength and weaknesses. Due to their orthogonality properties and their used algorithms their view on the data is slightly different. By assuming orthogonality between common and distinctive, true natural or biological phenomena that may not be orthogonal at all might be misinterpreted.

  4. Complex dynamics

    CERN Document Server

    Carleson, Lennart


    Complex dynamics is today very much a focus of interest. Though several fine expository articles were available, by P. Blanchard and by M. Yu. Lyubich in particular, until recently there was no single source where students could find the material with proofs. For anyone in our position, gathering and organizing the material required a great deal of work going through preprints and papers and in some cases even finding a proof. We hope that the results of our efforts will be of help to others who plan to learn about complex dynamics and perhaps even lecture. Meanwhile books in the field a. re beginning to appear. The Stony Brook course notes of J. Milnor were particularly welcome and useful. Still we hope that our special emphasis on the analytic side will satisfy a need. This book is a revised and expanded version of notes based on lectures of the first author at UCLA over several \\Vinter Quarters, particularly 1986 and 1990. We owe Chris Bishop a great deal of gratitude for supervising the production of cour...

  5. and complex

    Directory of Open Access Journals (Sweden)

    Kamrin Ken


    Full Text Available Granular materials have a strange propensity to behave as either a complex media or a simple media depending on the precise question being asked. This review paper offers a summary of granular flow rheologies for well-developed or steady-state motion, and seeks to explain this dichotomy through the vast range of complexity intrinsic to these models. A key observation is that to achieve accuracy in predicting flow fields in general geometries, one requires a model that accounts for a number of subtleties, most notably a nonlocal effect to account for cooperativity in the flow as induced by the finite size of grains. On the other hand, forces and tractions that develop on macro-scale, submerged boundaries appear to be minimally affected by grain size and, barring very rapid motions, are well represented by simple rate-independent frictional plasticity models. A major simplification observed in experiments of granular intrusion, which we refer to as the ‘resistive force hypothesis’ of granular Resistive Force Theory, can be shown to arise directly from rate-independent plasticity. Because such plasticity models have so few parameters, and the major rheological parameter is a dimensionless internal friction coefficient, some of these simplifications can be seen as consequences of scaling.

  6. Gauge cooling for the singular-drift problem in the complex Langevin method — a test in Random Matrix Theory for finite density QCD (United States)

    Nagata, Keitaro; Nishimura, Jun; Shimasaki, Shinji


    Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a generalized Banks-Casher relation as we confirm explicitly.

  7. Gauge cooling for the singular-drift problem in the complex Langevin method — a test in Random Matrix Theory for finite density QCD

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Keitaro [KEK Theory Center, High Energy Accelerator Research Organization,1-1 Oho, Tsukuba 305-0801 (Japan); Nishimura, Jun [KEK Theory Center, High Energy Accelerator Research Organization,1-1 Oho, Tsukuba 305-0801 (Japan); Department of Particle and Nuclear Physics, School of High Energy Accelerator Science,Graduate University for Advanced Studies (SOKENDAI), 1-1 Oho, Tsukuba 305-0801 (Japan); Shimasaki, Shinji [KEK Theory Center, High Energy Accelerator Research Organization,1-1 Oho, Tsukuba 305-0801 (Japan); Research and Education Center for Natural Sciences, Keio University,Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521 (Japan)


    Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a generalized Banks-Casher relation as we confirm explicitly.

  8. Fixation of Soil Using PEC and Separation of Fixed Soil

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Suk; Yang, Hee-Man; Lee, Kune Woo; Seo, Bum-Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)


    Radioactive cesium (Cs-137) is the most apprehensive element due to its long half-lives, high solubility in water, and strong radiation emission in the form of gamma rays. Because the radioactivity is localized within topsoil, soil surface on topsoil should be fixed to prevent the spreading of the contaminated soils by wind and water erosion. Many methods have been developing for soil fixation to remove radioactive contaminants in soil and prevent to diffuse radioactive materials. Various materials have been used as fixatives such as clays, molecular sieves, polymer, and petroleum based products. One of the methods is a soil fixation or solidification using polyelectrolyte. Polyelectrolytes have many ionic groups and form the polyelectrolyte complex (PEC) due to electrostatic interaction of anion and cation in an aqueous solution. polyelectrolyte complex can fix soil particles by flocculation and formation of crust between soil. The method can prevent a spread of radioactive material by floating on a soil surface. The decontamination efficiency of the surface soils reached about 90%, and dust release was effectively suppressed during the removal of surface soils. However it has a problem that the removed soil must separate soil and polymer to treat as the waste. In this study, the fixation of soil by polyelectrolyte complex to suppress the spread of contaminant and the separation method of soil and polymer was investigated. The properties of polyelectrolyte complex solution and the stability of fixed soil by polyelectrolyte complex were investigated. The concentration of salt in the polyelectrolyte complex solution is a very important parameter for the soil fixation.

  9. Cosmic Complexity (United States)

    Mather, John C.


    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  10. Passive blood plasma separation at the microscale: a review of design principles and microdevices (United States)

    Tripathi, Siddhartha; Bala Varun Kumar, Y. V.; Prabhakar, Amit; Joshi, Suhas S.; Agrawal, Amit


    Blood plasma separation is vital in the field of diagnostics and health care. Due to the inherent advantages obtained in the transition to microscale, the recent trend in these fields is a rapid shift towards the miniaturization of complex macro processes. Plasma separation in microdevices is one such process which has received extensive attention from researchers globally. Blood plasma separation techniques based on microfluidic platforms can be broadly classified into two categories. While active techniques utilize external force fields for separation, the passive techniques are dependent on biophysical effects, cell behavior, hydrodynamic forces and channel geometry for blood plasma separation. In general, passive separation methods are favored in comparison to active methods because they tend to avoid design complexities and are relatively easy to integrate with biosensors; additionally they are cost effective. Here we review passive separation techniques demonstrating separation and blood behavior at microscale. We present an extensive review of relevant biophysical laws, along with experimental details of various passive separation techniques and devices exploiting these physical effects. The relative performances, and the advantages and disadvantages of microdevices discussed in the literature, are compared and future challenges are brought about.

  11. Citrate based ``TALSPEAK`` lanthanide-actinide separation process

    Energy Technology Data Exchange (ETDEWEB)

    Del Cul, G.D.; Bond, W.D.; Toth, L.M.; Davis, G.D.; Dai, S.; Metcalf, D.H.


    The potential hazard posed to future generations by long-lived radionuclides such as the transuranic elements (TRU) is perceived as a major problem associated with the use of nuclear power. TRU wastes have to remain isolated from the environment for ``geological`` periods of time. The costs of building, maintaining, and operating a ``geological TRU repository`` can be very high. Therefore, there are significant economical advantages in segregating the relatively low volume of TRU wastes from other nuclear wastes. The chemical behavior of lanthanides and actinides, 4f and 5f elements respectively, is rather similar. As a consequence, the separation of these two groups is difficult. The ``TALSPEAK`` process (Trivalent Actinide Lanthanide Separations by Phosphorus-reagent Extraction from Aqueous Complexes) is one of the few means available to separate the trivalent actinides from the lanthanides. The method is based on the preferential complexation of the trivalent actinides by an aminopolyacetic acid. Cold experiments showed that by using citric acid the deleterious effects produced by impurities such as zirconium are greatly reduced.

  12. Mathematical Modeling of Nonstationary Separation Processes in Gas Centrifuge Cascade for Separation of Multicomponent Isotope Mixtures

    Directory of Open Access Journals (Sweden)

    Orlov Alexey


    Full Text Available This article presents results of development of the mathematical model of nonstationary separation processes occurring in gas centrifuge cascades for separation of multicomponent isotope mixtures. This model was used for the calculation parameters of gas centrifuge cascade for separation of germanium isotopes. Comparison of obtained values with results of other authors revealed that developed mathematical model is adequate to describe nonstationary separation processes in gas centrifuge cascades for separation of multicomponent isotope mixtures.

  13. Function spaces and d -separability | Tkachuk | Quaestiones ...

    African Journals Online (AJOL)

    The object of this paper is to study when a function space is d-separable, i.e., has a dense σ-discrete subspace. Several sufficient conditions are obtained for Cp(X) to be d-separable; as an application it is proved that Cp(X) is d-separable for any Corson compact space X. We give a characterization for Cp(X) × Cp(X) to be ...


    Marshall, L.


    An apparatus and method are described for separating charged, high energy particles of equal momentum forming a beam where the particles differ slightly in masses. Magnetic lenses are utilized to focus the beam and maintain that condition while electrostatic fields located between magnetic lenses are utilized to cause transverse separation of the particles into two beams separated by a sufficient amount to permit an aperture to block one beam. (AEC)

  15. Centrifugal Separation of Antiprotons and Electrons

    CERN Document Server

    Gabrielse, G; McConnell, R; Richerme, P; Wrubel, J; Kalra, R; Novitski, E; Grzonka, D; Oelert, W; Sefzick, T; Zielinski, M; Borbely, J S; Fitzakerley, D; George, M C; Hessels, E A; Storry, C H; Weel, M; Mullers, A; Walz, J; Speck, A


    Centrifugal separation of antiprotons and electrons is observed, the first such demonstration with particles that cannot be laser cooled or optically imaged. The spatial separation takes place during the electron cooling of trapped antiprotons, the only method available to produce cryogenic antiprotons for precision tests of fundamental symmetries and for cold antihydrogen studies. The centrifugal separation suggests a new approach for isolating low energy antiprotons and for producing a controlled mixture of antiprotons and electrons.

  16. Isotope separation in a "seeded beam%". (United States)

    Anderson, J B; Davidovits, P


    A new method of separating isotopes in a gaseous mixture is described. The method takes advantage of the differences in velocities of isotopic species in a molecular beam formed by expansion of the mixture with a light gas from a nozzle source. For the separation of the hexafluorides of uranium-235 and uranium-238 the technique has an estimated separative work factor about 500 times higher than the gaseous diffusion process and 100 times higher than the curved-jet method.

  17. Sessions and Separability in Security Protocols

    DEFF Research Database (Denmark)

    Carbone, Marco; Guttman, Joshua


    uncompromised subset of the participants are still guar- anteed that their interaction will respect sessions. A protocol transfor- mation turns any protocol into a session-respecting protocol. We do this via a general theory of separability. Our main theorem ap- plies to different separability requirements......, and characterizes when we can separate protocol executions sufficiently to meet a particular require- ment. This theorem also gives direct proofs of some old and new protocol composition results. Thus, our theory of separability appears to cover protocol composition and session-like behavior within a uniform frame...

  18. Rare earth separations by selective borate crystallization

    National Research Council Canada - National Science Library

    Xuemiao Yin; Yaxing Wang; Xiaojing Bai; Yumin Wang; Lanhua Chen; Chengliang Xiao; Juan Diwu; Shiyu Du; Zhifang Chai; Thomas E Albrecht-schmitt; Shuao Wang


      Lanthanides possess similar chemical properties rendering their separation from one another a challenge of fundamental chemical and global importance given their incorporation into many advanced technologies...

  19. Measuring Laminar-Separation Bubbles On Airfoils (United States)

    Stack, John P.; Mangalam, Sivaramakrishnan M.


    Nonintrusive multielement heat-transfer sensor overcomes limitations of previous methods. New technique determines simultaneously extent of laminar boundary layer and locations of laminar separation, transition in separated layer, and turbulent reattachment. In tests, only small amounts of heat introduced, and heated thin films caused little disturbance to shear layer or to each other. Promising tool for measurements of stability of laminar boundary layers, separated shear layers, and transitional separation bubbles. Simple and capable of providing comprehensive picture of state of shear flow along entire surface. Significant savings in tunnel (or flight) test time with corresponding savings in cost.

  20. Separation science and technology: an ORNL perspective

    Energy Technology Data Exchange (ETDEWEB)

    Pruett, D.J.


    This report was prepared as a summary of a fourfold effort: (1) to examine schemes for defining and categorizing the field of separation science and technology; (2) to review several of the major categories of separation techniques in order to determine the most recent developments and future research needs; (3) to consider selected problems and programs that require advances in separation science and technology as a part of their solution; and (4) to propose suggestions for new directions in separation research at Oak Ridge National Laboratory (ORNL).

  1. Size separation of analytes using monomeric surfactants (United States)

    Yeung, Edward S.; Wei, Wei


    A sieving medium for use in the separation of analytes in a sample containing at least one such analyte comprises a monomeric non-ionic surfactant of the of the general formula, B-A, wherein A is a hydrophilic moiety and B is a hydrophobic moiety, present in a solvent at a concentration forming a self-assembled micelle configuration under selected conditions and having an aggregation number providing an equivalent weight capable of effecting the size separation of the sample solution so as to resolve a target analyte(s) in a solution containing the same, the size separation taking place in a chromatography or electrophoresis separation system.

  2. Coexistence of Strategic Vertical Separation and Integration

    DEFF Research Database (Denmark)

    Jansen, Jos


    This paper gives conditions under which vertical separation is chosen by some upstream firms, while vertical integration is chosen by others in the equilibrium of a symmetric model. A vertically separating firm trades off fixed contracting costs against the strategic benefit of writing a (two......-part tariff, exclusive dealing) contract with its retailer. Coexistence emerges when more than two vertical Cournot oligopolists supply close substitutes. When vertical integration and separation coexist, welfare could be improved by reducing the number of vertically separating firms. The scope...

  3. Centrifugal separators and related devices and methods

    Energy Technology Data Exchange (ETDEWEB)

    Meikrantz, David H [Idaho Falls, ID; Law, Jack D [Pocatello, ID; Garn, Troy G [Idaho Falls, ID; Macaluso, Lawrence L [Carson City, NV; Todd, Terry A [Aberdeen, ID


    Centrifugal separators and related methods and devices are described. More particularly, centrifugal separators comprising a first fluid supply fitting configured to deliver fluid into a longitudinal fluid passage of a rotor shaft and a second fluid supply fitting sized and configured to sealingly couple with the first fluid supply fitting are described. Also, centrifugal separator systems comprising a manifold having a drain fitting and a cleaning fluid supply fitting are described, wherein the manifold is coupled to a movable member of a support assembly. Additionally, methods of cleaning centrifugal separators are described.

  4. Separation of water through gas hydrate formation

    DEFF Research Database (Denmark)

    Boch Andersen, Torben; Thomsen, Kaj


    Gas hydrate is normally recognized as a troublemaker in the oil and gas industry. However, gas hydrate has some interesting possibilities when used in connection with separation of water. Nordic Sugar has investigated the possibility of using gas hydrates for concentration of sugar juice. The goal...... of the project was to formulate an alternative separation concept, which can replace the traditional water evaporation process in the sugar production. Work with the separation concept showed that gas hydrates can be used for water separation. The process is not suitable for sugar production because of large...

  5. Simultaneous separation and determination of Tl(I) and Tl(III) by IC ...

    African Journals Online (AJOL)

    Simultaneous separation and determination of Tl(I) and Tl(III) by IC-ICP-OES and IC-ICP-MS. PP Coetzee, JL Fischer, M Hu. Abstract. A new hyphenated method was developed for the speciation of Tl. In this method, Tl(III) was complexed with DTPA to form a Tl(III)-DTPA anionic complex. Tl(I) did not form a complex with ...

  6. Evaluation of a silicon oxynitride hydrophilic interaction liquid chromatography column in saccharide and glycoside separations. (United States)

    Wan, Huihui; Sheng, Qianying; Zhong, Hongmin; Guo, Xiujie; Fu, Qing; Liu, Yanfang; Xue, Xingya; Liang, Xinmiao


    The retention characteristics of a silicon oxynitride stationary phase for carbohydrate separation were studied in hydrophilic interaction chromatography mode. Four saccharides including mono-, di-, and trisaccharides were employed to investigate the effects of water content and buffer concentration in the mobile phase on hydrophilic interaction liquid chromatography retention. For the tested saccharides, the silicon oxynitride column demonstrated excellent performance in terms of separation efficiency, hydrophilicity, and interesting separation selectivity for carbohydrates compared to the bare silica stationary phase. Finally, the silicon oxynitride hydrophilic interaction liquid chromatography column was employed in the separation of complex samples of fructooligosaccharides, saponins, and steviol glycoside from natural products. The resulting chromatograms demonstrated good separation efficiency and longer retention compared with silica, which further confirmed the advantages and potential application of silicon oxynitride stationary phase for hydrophilic interaction liquid chromatography separation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. An Aircraft Separation Algorithm with Feedback and Perturbation (United States)

    White, Allan L.


    A separation algorithm is a set of rules that tell aircraft how to maneuver in order to maintain a minimum distance between them. This paper investigates demonstrating that separation algorithms satisfy the FAA requirement for the occurrence of incidents by means of simulation. Any demonstration that a separation algorithm, or any other aspect of flight, satisfies the FAA requirement is a challenge because of the stringent nature of the requirement and the complexity of airspace operations. The paper begins with a probability and statistical analysis of both the FAA requirement and demonstrating meeting it by a Monte Carlo approach. It considers the geometry of maintaining separation when one plane must change its flight path. It then develops a simple feedback control law that guides the planes on their paths. The presence of feedback control permits the introduction of perturbations, and the stochastic nature of the chosen perturbation is examined. The simulation program is described. This paper is an early effort in the realistic demonstration of a stringent requirement. Much remains to be done.

  8. Mars Atmospheric Capture and Gas Separation (United States)

    Muscatello, Anthony; Santiago-Maldonado, Edgardo; Gibson, Tracy; Devor, Robert; Captain, James


    The Mars atmospheric capture and gas separation project is selecting, developing, and demonstrating techniques to capture and purify Martian atmospheric gases for their utilization for the production of hydrocarbons, oxygen, and water in ISRU systems. Trace gases will be required to be separated from Martian atmospheric gases to provide pure C02 to processing elements. In addition, other Martian gases, such as nitrogen and argon, occur in concentrations high enough to be useful as buffer gas and should be captured as welL To achieve these goals, highly efficient gas separation processes will be required. These gas separation techniques are also required across various areas within the ISRU project to support various consumable production processes. The development of innovative gas separation techniques will evaluate the current state-of-the-art for the gas separation required, with the objective to demonstrate and develop light-weight, low-power methods for gas separation. Gas separation requirements include, but are not limited to the selective separation of: (1) methane and water from un-reacted carbon oxides (C02- CO) and hydrogen typical of a Sabatier-type process, (2) carbon oxides and water from unreacted hydrogen from a Reverse Water-Gas Shift process, (3) carbon oxides from oxygen from a trash/waste processing reaction, and (4) helium from hydrogen or oxygen from a propellant scavenging process. Potential technologies for the separations include freezers, selective membranes, selective solvents, polymeric sorbents, zeolites, and new technologies. This paper and presentation will summarize the results of an extensive literature review and laboratory evaluations of candidate technologies for the capture and separation of C02 and other relevant gases.

  9. Ceramic membranes for high temperature hydrogen separation

    Energy Technology Data Exchange (ETDEWEB)

    Fain, D.E.; Roettger, G.E. [Oak Ridge K-25 Site, TN (United States)


    Ceramic gas separation membranes can provide very high separation factors if the pore size is sufficiently small to separate gas molecules by molecular sieving and if oversized pores are adequately limited. Ceramic membranes typically have some pores that are substantially larger than the mean pore size and that should be regarded as defects. To assess the effects of such defects on the performance of ceramic membranes, a simple mathematical model has been developed to describe flow through a gas separation membrane that has a primary mode of flow through very small pores but that has a secondary mode of flow through undesirably large pores. This model permits separation factors to be calculated for a specified gas pair as a function of the molecular weights and molecular diameters of the gases, the membrane pore diameter, and the diameter and number of defects. This model will be described, and key results from the model will be presented. The separation factors of the authors membranes continue to be determined using a permeance test system that measures flows of pure gases through a membrane at temperatures up to 275{degrees}C. A primary goal of this project for FY 1996 is to develop a mixed gas separation system for measuring the separation efficiency of membranes at higher temperatures. Performance criteria have been established for the planned mixed gas separation system and design of the system has been completed. The test system is designed to measure the separation efficiency of membranes at temperatures up to 600{degrees}C and pressures up to 100 psi by separating the constituents of a gas mixture containing hydrogen. The system will accommodate the authors typical experimental membrane that is tubular and has a diameter of about 9 mm and a length of about 23 cm. The design of the new test system and its expected performance will be discussed.

  10. Finger prick blood plasma separation using a standard lab equipment

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Pfreundt, Andrea

    Blood is a complex biological matrix that has a huge potential for diagnostics as it contains various analytes and biomarkers. Traditionally the analysis is performed on plasma and white blood cells separated from venous blood. However, the collection of venous blood samples is painful and requires...... present a device for analysis of minute blood volumes using a standard laboratory tabletop spinner. The microfabricated polymer device fits in a 1.5 mL eppendorf tube and takes between 10-20 μl of whole blood. The blood is layered over a pre-loaded Ficoll paque® that is used to separate the plasma...... a few milliliters of blood. It has been demonstrated that the blood taken from finger prick contains the same analytes as venous blood in sufficient abundance and could therefore be used for diagnosis as an alternative in many cases. Various approaches towards analysis of finger prick blood with plasma...

  11. Liquid-liquid separation using steady-state bed coalescer

    Directory of Open Access Journals (Sweden)

    Šećerov-Sokolović Radmila M.


    Full Text Available This paper presents a literature review on the current understanding of liquid-liquid separation that is immensely widespread in practice, highlighting the steady-state bed coalescer being a good solution in various engineering application. Generally, the fibre bed coalescence has proven to be very effective separation method in the industry. Due to the complexity of bed coalescence phenomenon coalescer design and sizing procedure relies on experimental test. This review provides a research overview of the key phenomena essential for the efficient bed coalescence, such as mechanisms of droplet coalescence and emulsion flow through the fibre bed. In addition to this provides an overview of the current knowledge about coalescer´s design properties and variables such as: fluid velocity, fluid flow orientation/flow mode, fibre bed geometry, and bed length. [[Projekat Ministarstva nauke Republike Srbije, br. 172022

  12. Separation of carbohydrates using hydrophilic interaction liquid chromatography. (United States)

    Fu, Qing; Liang, Tu; Li, Zhenyu; Xu, Xiaoyong; Ke, Yanxiong; Jin, Yu; Liang, Xinmiao


    A strategy was developed to rapidly evaluate chromatographic properties of hydrophilic interaction chromatography (HILIC) columns for separating carbohydrates. Seven HILIC columns (Silica, Diol, TSK Amide-80, XAmide, Click Maltose, Click β-CD, and Click TE-Cys columns) were evaluated by using three monosaccharide and seven disaccharides as probes. The influence of column temperature on the peak shape and tautomerization of carbohydrates, as well as column selectivity were investigated. The influence of surface charge property on the retention was also studied by using glucose, glucuronic acid, and glucosamine, which indicated that buffer salt concentration and pH value in mobile phase was necessary to control the ionic interactions between ionic carbohydrates and HILIC columns. According to evaluation results, the XAmide column was selected as an example to establish experimental schemes for separation of complex mixtures of oligosaccharide. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Phase Separation Dynamics in Isotropic Ion-Intercalation Particles

    CERN Document Server

    Zeng, Yi


    Lithium-ion batteries exhibit complex nonlinear dynamics, resulting from diffusion and phase transformations coupled to ion intercalation reactions. Using the recently developed Cahn-Hilliard reaction (CHR) theory, we investigate a simple mathematical model of ion intercalation in a spherical solid nanoparticle, which predicts transitions from solid-solution radial diffusion to two-phase shrinking-core dynamics. This general approach extends previous Li-ion battery models, which either neglect phase separation or postulate a spherical shrinking-core phase boundary, by predicting phase separation only under appropriate circumstances. The effect of the applied current is captured by generalized Butler-Volmer kinetics, formulated in terms of diffusional chemical potentials, and the model consistently links the evolving concentration profile to the battery voltage. We examine sources of charge/discharge asymmetry, such as asymmetric charge transfer and surface "wetting" by ions within the solid, which can lead to...

  14. Separate DOD and DOA Estimation for Bistatic MIMO Radar

    Directory of Open Access Journals (Sweden)

    Lin Li


    Full Text Available A novel MUSIC-type algorithm is derived in this paper for the direction of departure (DOD and direction of arrival (DOA estimation in a bistatic MIMO radar. Through rearranging the received signal matrix, we illustrate that the DOD and the DOA can be separately estimated. Compared with conventional MUSIC-type algorithms, the proposed separate MUSIC algorithm can avoid the interference between DOD and DOA estimations effectively. Therefore, it is expected to give a better angle estimation performance and have a much lower computational complexity. Meanwhile, we demonstrate that our method is also effective for coherent targets in MIMO radar. Simulation results verify the efficiency of the proposed method, particularly when the signal-to-noise ratio (SNR is low and/or the number of snapshots is small.

  15. Surveillance Range and Interference Impacts on Self-Separation Performance (United States)

    Idris, Husni; Consiglio, Maria C.; Wing, David J.


    Self-separation is a concept of flight operations that aims to provide user benefits and increase airspace capacity by transferring traffic separation responsibility from ground-based controllers to the flight crew. Self-separation is enabled by cooperative airborne surveillance, such as that provided by the Automatic Dependent Surveillance-Broadcast (ADSB) system and airborne separation assistance technologies. This paper describes an assessment of the impact of ADS-B system performance on the performance of self-separation as a step towards establishing far-term ADS-B performance requirements. Specifically, the impacts of ADS-B surveillance range and interference limitations were analyzed under different traffic density levels. The analysis was performed using a batch simulation of aircraft performing self-separation assisted by NASA s Autonomous Operations Planner prototype flight-deck tool, in two-dimensional airspace. An aircraft detected conflicts within a look-ahead time of ten minutes and resolved them using strategic closed trajectories or tactical open maneuvers if the time to loss of separation was below a threshold. While a complex interaction was observed between the impacts of surveillance range and interference, as both factors are physically coupled, self-separation performance followed expected trends. An increase in surveillance range resulted in a decrease in the number of conflict detections, an increase in the average conflict detection lead time, and an increase in the percentage of conflict resolutions that were strategic. The majority of the benefit was observed when surveillance range was increased to a value corresponding to the conflict detection look-ahead time. The benefits were attenuated at higher interference levels. Increase in traffic density resulted in a significant increase in the number of conflict detections, as expected, but had no effect on the conflict detection lead time and the percentage of conflict resolutions that were

  16. Bacteriophage-based nanoprobes for rapid bacteria separation (United States)

    Chen, Juhong; Duncan, Bradley; Wang, Ziyuan; Wang, Li-Sheng; Rotello, Vincent M.; Nugen, Sam R.


    The lack of practical methods for bacterial separation remains a hindrance for the low-cost and successful development of rapid detection methods from complex samples. Antibody-tagged magnetic particles are commonly used to pull analytes from a liquid sample. While this method is well-established, improvements in capture efficiencies would result in an increase of the overall detection assay performance. Bacteriophages represent a low-cost and more consistent biorecognition element as compared to antibodies. We have developed nanoscale bacteriophage-tagged magnetic probes, where T7 bacteriophages were bound to magnetic nanoparticles. The nanoprobe allowed the specific recognition and attachment to E. coli cells. The phage magnetic nanprobes were directly compared to antibody-conjugated magnetic nanoprobes. The capture efficiencies of bacteriophages and antibodies on nanoparticles for the separation of E. coli K12 at varying concentrations were determined. The results indicated a similar bacteria capture efficiency between the two nanoprobes.The lack of practical methods for bacterial separation remains a hindrance for the low-cost and successful development of rapid detection methods from complex samples. Antibody-tagged magnetic particles are commonly used to pull analytes from a liquid sample. While this method is well-established, improvements in capture efficiencies would result in an increase of the overall detection assay performance. Bacteriophages represent a low-cost and more consistent biorecognition element as compared to antibodies. We have developed nanoscale bacteriophage-tagged magnetic probes, where T7 bacteriophages were bound to magnetic nanoparticles. The nanoprobe allowed the specific recognition and attachment to E. coli cells. The phage magnetic nanprobes were directly compared to antibody-conjugated magnetic nanoprobes. The capture efficiencies of bacteriophages and antibodies on nanoparticles for the separation of E. coli K12 at varying

  17. Fundamental aspects of phase separation microfabrication

    NARCIS (Netherlands)

    Bikel, M.


    In the research featured in this PhD thesis, the fundamental aspects of Phase Separation MicroFabrication (PSµF) were studied. PSµF is a technique through which polymeric porous films with defined structures on their surfaces can be created. This is achieved by phase separation of polymer solutions

  18. Convex Sets Strict Separation in Hilbert Spaces


    Ferreira, Manuel Alberto M.; Filipe, José António


    Convex sets separation is very important in convex programming, a very powerful mathematical tool for operations research, management and economics, for example. The target of this work is to present Theorem 3.1 that gives sufficient conditions for the strict separation of convex sets.

  19. Ethanol-water separation by pervaporation

    NARCIS (Netherlands)

    Mulder, M.H.V.; Oude Hendrickman, J.; Hegeman, H.; Smolders, C.A.


    The separation of ethanol-water mixtures is of great importance for the production of ethanol from biomass. Both ultrafiltration and pervaporation processes can be used for the continuous processing of fermentation and separation, The removal of ethanol from the ultrafiltration permeate can be

  20. Hydrodynamic blood plasma separation in microfluidic channels

    DEFF Research Database (Denmark)

    Jouvet, Lionel


    The separation of red blood cells from plasma flowing in microchannels is possible by biophysical effects such as the Zweifach–Fung bifurcation law. In the present study, daughter channels are placed alongside a main channel such that cells and plasma are collected separately. The device is aimed...

  1. Apparatus for separating solids from a liquid

    NARCIS (Netherlands)

    Rem, P.C.; Berkhout, S.P.M.


    The invention relates to an apparatus and a method for separating a material stream consisting of several materials. The materials to be separated have different densities or density ranges, so that the material of the highest density can be discharged through a screen of the apparatus, while the

  2. Passive gas separator and accumulator device (United States)

    Choe, H.; Fallas, T.T.


    A separation device employing a gas separation filter and swirler vanes for separating gas from a gas-liquid mixture is provided. The cylindrical filter utilizes the principle that surface tension in the pores of the filter prevents gas bubbles from passing through. As a result, the gas collects in the interior region of the filter and coalesces to form larger bubbles in the center of the device. The device is particularly suited for use in microgravity conditions since the swirlers induce a centrifugal force which causes liquid to move from the inner region of the filter, pass the pores, and flow through the outlet of the device while the entrained gas is trapped by the filter. The device includes a cylindrical gas storage screen which is enclosed by the cylindrical gas separation filter. The screen has pores that are larger than those of the filters. The screen prevents larger bubbles that have been formed from reaching and interfering with the pores of the gas separation filter. The device is initially filled with a gas other than that which is to be separated. This technique results in separation of the gas even before gas bubbles are present in the mixture. Initially filling the device with the dissimilar gas and preventing the gas from escaping before operation can be accomplished by sealing the dissimilar gas in the inner region of the separation device with a ruptured disc which can be ruptured when the device is activated for use. 3 figs.

  3. Separation mechanisms in a plasma centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Timchenko, N.N.; Khripunov, B.I.


    The separation of elements and isotopes is studied in a fully ionized plasma with crossed E and H fields. Two separation mechanisms, the centrifuge mechanism and polarization, are discussed. The parameter ranges in which each of these mechanisms is important are found. The mechanisms are compared in terms of relative efficiency.

  4. Early repeated maternal separation induces alterations of ...

    Indian Academy of Sciences (India)

    The long-term effects of repeated maternal separation (MS) during early postnatal life on reelin expression in the hippocampus of developing rats were investigated in the present study. MS was carried out by separating Wistar rat pups singly from their mothers for 3 h a day during postnatal days (PND) 2–14. Reelin mRNA ...

  5. Mothers' Mobility after Separation : Do Grandmothers Matter?

    NARCIS (Netherlands)

    Das, Marjolijn; de Valk, Helga; Merz, Eva-Maria


    Starting from a life course perspective, this study aims to gain more insight into mobility patterns of recently separated mothers, focusing especially on moves to the location of their own mother: the maternal grandmother. Separated mothers, having linked lives with their own mothers, may benefit

  6. Mothers' Mobility after Separation: Do Grandmothers Matter?

    NARCIS (Netherlands)

    Das, M.; de Valk, H.A.G.; Merz, E.-M.


    Starting from a life course perspective, this study aims to gain more insight into mobility patterns of recently separated mothers, focusing especially on moves to the location of their own mother: the maternal grandmother. Separated mothers, having linked lives with their own mothers, may benefit

  7. Recycling of WEEE by magnetic density separation

    NARCIS (Netherlands)

    Hu, B.; Giacometti, L.; Di Maio, F.; Rem, P.C.


    The paper introduces a new recycling method of WEEE: Magnetic Density Separation. By using this technology, both grade and recovery rate of recycled products are over 90%. Good separations are not only observed in relatively big WEEE samples, but also in samples with smaller sizes or electrical

  8. 7 CFR 201.47 - Separation. (United States)


    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Separation. 201.47 Section 201.47 Agriculture... REGULATIONS Purity Analysis in the Administration of the Act § 201.47 Separation. (a) The working sample shall... percentage of each part shall be determined to two decimal places. (b) Aids for the classification of pure...

  9. Laminar separation bubbles: Dynamics and control

    Indian Academy of Sciences (India)

    it thus are essential prerequisites for efficient design of these aerodynamic devices. Gaster. (1967) was the first to systematically explore the stability characteristics associated with the transition taking place in separation bubble. Many recent studies have been directed towards exploring the dynamics of separation bubbles ...

  10. Laminar separation bubbles: Dynamics and control

    Indian Academy of Sciences (India)

    This work is an experimental investigation of the dynamics and control of the laminar separation bubbles which are typically present on the suction surface of an aerofoil at a large angle of attack. A separation bubble is produced on the upper surface of a flat plate by appropriately contouring the top wall of the wind tunnel.

  11. Removal of micropollutants in source separated sanitation

    NARCIS (Netherlands)

    Butkovskyi, A.


    Source separated sanitation is an innovative sanitation method designed for minimizing use of energy and clean drinking water, and maximizing reuse of water, organics and nutrients from waste water. This approach is based on separate collection and treatment of toilet wastewater (black water) and

  12. Optimization of the Separation Parameters and Indicators of Separation Efficiency of Buckwheat Seeds

    Directory of Open Access Journals (Sweden)

    Stanisław Konopka


    Full Text Available The separation parameters and the indicators of separation efficiency for buckwheat seeds and impurities that are difficult to separate were optimized with the use of self-designed software based on genetic algorithms. The results of the calculations differed significantly from the suboptimal values determined in previous studies. The optimal values of the indicator of separation efficiency were higher; whereas the values of the indicator of buckwheat seed loss were significantly lower. The optimal working parameters for a seed separator in order to promote separation efficiency were determined.

  13. Bio-/Photo-Chemical Separation and Recovery of Uranium

    Energy Technology Data Exchange (ETDEWEB)

    Francis,A.J.; Dodge, C.J.


    Citric acid forms bidentate, tridentate, binuclear or polynuclear species with transition metals and actinides. Biodegradation of metal citrate complexes is influenced by the type of complex formed with metal ions. While bidentate complexes are readily biodegraded, tridentate, binuclear and polynuclear species are recalcitrant. Likewise certain transition metals and actinides are photochemically active in the presence of organic acids. Although the uranyl citrate complex is not biodegraded, in the presence of visible light it undergoes photochemical oxidation/reduction reactions which result in the precipitation of uranium as UO{sub 3} {center_dot} H{sub 2}O. Consequently, we developed a process where uranium is extracted from contaminated soils and wastes by citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, whereas uranyl citrate which is recalcitrant remains in solution. Photochemical degradation of the uranium citrate complex resulted in the precipitation of uranium. Thus the toxic metals and uranium in mixed waste are recovered in separate fractions for recycling or for disposal. The use of naturally-occurring compounds and the combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in cost.

  14. Quenching Phase Separation by Vapor Deposition Polymerization (United States)

    Tao, Ran; Anthamatten, Mitchell


    Initiated chemical vapor deposition (iCVD) is a solventless, free radical technique predominately used to deposit homogeneous films of linear and crosslinked polymers directly from gas phase feeds. We report a template-free method to fabricate continuous-phase porous polymer films by simultaneous phase separation during iCVD. Phase separation during film growth is achieved by condensing an inert porogen, along with initiator, monomer, and crosslinker. When the vapor mixture transports to the cooled substrate, phase separation occurs along with polymerization and crosslinking, which quench the state of phase separation. The kinetics of spontaneously phase separation can be qualitatively understood on the basis of Cahn-Hilliard theory. A series of films were grown by varying monomer and porogen's degree of saturation. Deposited films were studied by electron microscopy and spectroscopic techniques.

  15. Advanced Aqueous Separation Systems for Actinide Partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Kenneth L.; Clark, Sue; Meier, G Patrick; Alexandratos, Spiro; Paine, Robert; Hancock, Robert; Ensor, Dale


    One of the most challenging aspects of advanced processing of spent nuclear fuel is the need to isolate transuranium elements from fission product lanthanides. This project expanded the scope of earlier investigations of americium (Am) partitioning from the lanthanides with the synthesis of new separations materials and a centralized focus on radiochemical characterization of the separation systems that could be developed based on these new materials. The primary objective of this program was to explore alternative materials for actinide separations and to link the design of new reagents for actinide separations to characterizations based on actinide chemistry. In the predominant trivalent oxidation state, the chemistry of lanthanides overlaps substantially with that of the trivalent actinides and their mutual separation is quite challenging.

  16. Gas-filled separators - An overview

    CERN Document Server

    Leino, M


    Gas-filled recoil separators have been used in nuclear physics studies since the early fifties. Most notably, they have found use in the separation of evaporation residues of heavy and very heavy elements from unwanted background. Gas-filled separators, alone or coupled to a detector array, offer an efficient, fast, compact and relatively inexpensive solution for nuclear structure studies. A new application is the use of a gas-filled device as a pre-separator in the study of chemical properties of the heaviest elements. Other uses include systematic study of fusion evaporation cross sections and accelerator mass spectrometry. In this contribution, an overview on gas-filled recoil separators, their characteristics, fields of application and possible future developments is given.

  17. Molecular design of materials for cell separation. (United States)

    Kataoka, K


    There has been a strong demand in biomedical sciences to isolate viable cell populations with high yield and purity. An important facet of this work was to develop new polymeric adsorbent for the separation of lymphocyte subpopulations. Based on our strategy of separating cells through their differential ionic affinity toward multiphase-structured adsorbent with ionically derivatized microdomains, a series of poly(2-hydroxyethyl methacrylate)/polyamine graft copolymers (HA copolymers) was prepared. HA copolymer columns were found to show specific adsorption affinity toward B lymphocytes, and allows for separation of B and T lymphocytes in high yield and purity with a short operating time. Separation mechanism involved in the resolution of B and T lymphocytes by HA copolymer column is discussed in this paper. Further, photo-induced desorption of cells from the adsorbent derivatized with photo-responsive functional group (azobenzene group) was demonstrated to emphasize the feasibility of photo-regulated chromatography as a novel tool in cell separation technology.

  18. Runge approximation on convex sets implies the Oka property


    Forstneric, Franc


    We prove that the classical Oka property of a complex manifold Y, concerning the existence and homotopy classification of holomorphic mappings from Stein manifolds to Y, is equivalent to a Runge approximation property for holomorphic maps from compact convex sets in Euclidean spaces to Y.

  19. Stable cohomology of the universal Picard varieties and the extended mapping class group

    DEFF Research Database (Denmark)

    Ebert, Johannes; Randal-Williams, Oscar


    these spaces to (a generalisation of) Kawazumi's extended mapping class groups, and hence deduce cohomological information about these. Finally, we relate these results to complex algebraic geometry. We construct a holomorphic stack classifying families of Riemann surfaces equipped with a fibrewise holomorphic...

  20. Ceramic membranes for high temperature hydrogen separation

    Energy Technology Data Exchange (ETDEWEB)

    Adcock, K.D.; Fain, D.E.; James, D.L.; Powell, L.E.; Raj, T.; Roettger, G.E.; Sutton, T.G. [East Tennessee Technology Park, Oak Ridge, TN (United States)


    The separative performance of the authors` ceramic membranes has been determined in the past using a permeance test system that measured flows of pure gases through a membrane at temperatures up to 275 C. From these data, the separation factor was determined for a particular gas pair from the ratio of the pure gas specific flows. An important project goal this year has been to build a Mixed Gas Separation System (MGSS) for measuring the separation efficiencies of membranes at higher temperatures and using mixed gases. The MGSS test system has been built, and initial operation has been achieved. The MGSS is capable of measuring the separation efficiency of membranes at temperatures up to 600 C and pressures up to 100 psi using a binary gas mixture such as hydrogen/methane. The mixed gas is fed into a tubular membrane at pressures up to 100 psi, and the membrane separates the feed gas mixture into a permeate stream and a raffinate stream. The test membrane is sealed in a stainless steel holder that is mounted in a split tube furnace to permit membrane separations to be evaluated at temperatures up to 600 C. The compositions of the three gas streams are measured by a gas chromatograph equipped with thermal conductivity detectors. The test system also measures the temperatures and pressures of all three gas streams as well as the flow rate of the feed stream. These data taken over a range of flows and pressures permit the separation efficiency to be determined as a function of the operating conditions. A mathematical model of the separation has been developed that permits the data to be reduced and the separation factor for the membrane to be determined.

  1. Application of dry separative methods for decreasing content the residues unburned coal and separation Fe from black coal flies ash

    Directory of Open Access Journals (Sweden)

    František Kaľavský


    Full Text Available Main obstacle using of fly ashes in building, that is its main consumer, is the residue of unburned coal; it is expressed of loss onignition - LOI. In present, the valid STN and EU standard limits the content of LOI to 3 – 5 %, in national conditions maximum 7 %.Application of processing technologies also has to assure utilization of fly ash that provides a possibility of complex utilizationof individual products obtained by modification.By means of corona separation, based on different conductivity of individual fly ash elements, it is possible to separate unburnedcoal particles. The fly ash sample from black coal burning in melting boiler that was deposited on fly ash deposit, content of LOIof dielectric particle 6,45 % at 61 % weight yield was achieved. In the samples taken from dry taking of fly ash the non-conductingproduct contained 7,72 % of LOI at 73 % of weight yield.

  2. Extraction and Separation of Fucoidan from Laminaria japonica with Chitosan as Extractant

    Directory of Open Access Journals (Sweden)

    Ronge Xing


    Full Text Available Herein the extraction method of fucoidan from Laminaria japonica is reported. Firstly, chitosan, chitosan-N-2-hydroxypropyl trimethyl ammonium chloride (HACC, and hexadecyltrimethylammonium bromide (CPAB were used to extract the fucoidan. The results showed that chitosan was the optimal extractant compared with the other two extractants. After extraction, different aqueous solutions, including NaCl, KCl, and HCl (pH2, were used to separate fucoidan from chitosan-fucoidan complex. The results showed that the separation ability of NaCl was slightly higher than that of KCl. Moreover, the price of NaCl is lower than that of KCl. Given the quality-price rate, NaCl solution was chosen as the separation solution. Thirdly, the concentration and ratio of NaCl solution : sediment influence the separation of fucoidan from chitosan-fucoidan complex. The results showed that the optimal separation conditions include 4 mol/L NaCl solution with the ratio of NaCl solution to sediment at 30 : 1. Fucoidan content was found to be affected by different separation time. Fucoidan content increased with the increase of separation time, and the optimal separation time was 6 h. Compared with traditional alkali extraction method, this method not only reduces the usage of alkali and acid and alleviate environment pollution, but also has the comparable extraction yield of fucoidan. It is a potential method for extraction of fucoidan.

  3. Separation of lanthanides through hydroxyapatite; Separacion de lantanidos mediante hidroxiapatita

    Energy Technology Data Exchange (ETDEWEB)

    Garcia M, F.G


    With the objective of obtaining from an independent way to each one of the lanthanides {sup 151} Pm, {sup 161} Tb, {sup 166} Ho and {sup 177} Lu free of carrier and with high specific activities starting from the indirect irradiation via, it intends in this work to determine the viability of separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu, by means of ion exchange column chromatography, using hydroxyapatite (HAp) and fluorite like absorbent material in complexing media. It is important to mention that have registered separation studies among lanthanides of the heavy group with those of the slight group, using the same mass and, in comparison with this work, quantities different from the father were used and of the son, also, that the separation studies were carried out among neighboring lanthanides. In this investigation, it was determined the effect that its have the complexing media: KSCN, sodium tartrate, sodium citrate, EDTA and aluminon, their pH and concentration, in the adsorption of the lanthanides in both minerals, in order to determine the chromatographic conditions for separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu. The work consists of five chapters, in the first one they are presented a theoretical introduction of the characteristics more important of the lanthanides, the hydroxyapatite and the fluorite; in the second, it is deepened in the ion exchange, as well as the two techniques (XRD and High Vacuum Electron Microscopy) to make the characterization of LnCI{sub 3} (Ln = Nd, Gd, Dy or Yb) synthesized. The third chapter, it describes the methodology continued in our experimental work; in the room, its are presented the obtained results of the static and dynamic method to determine the viability of separation of neighboring lanthanides; and finally, the five chapter shows the conclusions. In this study, it is concludes that the separation among neighboring lanthanides cannot be carried out in the minerals and used media; because

  4. Cadmium complexation by solid waste leachates

    DEFF Research Database (Denmark)

    Xu Ze Lun; Christensen, Thomas H.


    A previously reported method for determination of Cd species in solid waste leachates has been applied to ten leachate samples representing five different types of solid waste: refuse compost, flyash from coal combustion, sewage sludge, refuse incineration residues and landfilled municipal waste....... The leachates were spiked with Cd (separated into labile complexes......, slowly labile complexes and stable complexes. Leachates originating from the same type of solid waste showed different fractions of Cd, in particular with respect to free divalent Cd and stable Cd complexes. Only coal flyash showed almost identical fractions of Cd in the two leachates. The latter is due...

  5. Issues of separation and reunification in immigrant Latina youth. (United States)

    Schapiro, Naomi A


    Latinos make up 12.5% of the total U.S. population, and the largest source of migration to the United States is from Mexico. The intersection of acculturation and risk for Latino immigrant youth is complex, with recent arrivals being protected in the context of strong family ties. Youth, and particularly young women who have been separated from their parents during migration and later reunited, face particular problems that have not been well studied. This article discusses possible stresses facing reunified families, with implications for nursing practice and suggestions for future research.

  6. Extracting and conducting solids for the separation of actinides

    Energy Technology Data Exchange (ETDEWEB)

    Racimor, David; Picart, Sebastien; Thouvenot, Rene; Bidan, Gerard; Jobelin, Isabelle


    The preparation of both extracting and conducting materials for chromatography is of great interest for the separation of actinides [1,2]. Indeed, most of actinides are relatively stable in aqueous media at different oxidation states and their affinity for extracting group is dependant of this oxidation state. Thus, the possibility to perform an extraction on a solid support at a controlled potential could favour a specific interaction between an actinide at a precise oxidation state and a grafted ligand. This study then concerns the synthesis of conductive materials incorporating complexing poly-oxo-metallates in their structure.

  7. Thermodynamic Studies to Support Actinide/Lanthanide Separations

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Linfeng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    This milestone report summarizes the data obtained in FY15 on the complexation of HEDTA with Np(V) and U(VI) in a temperature range from 25 to 70°C. The results show the effect of temperature on the chemical speciation of Np(V) and U(VI) in the modified TALSPEAK Process, and help to evaluate the effectiveness of the process when the operation envelope (e.g., temperature) varies. Eventually, the results from this study will help to achieve a better control of the separation process based on the HEDTA/HEH[EHP] combination.

  8. Cesium and Strontium Separation Technologies Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst


    Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

  9. Trajectories of adjustment to couple relationship separation. (United States)

    Halford, W Kim; Sweeper, Susie


    To test a stress-diathesis model of adjustment to separation, the current study describes the trajectories of different aspects of separation adjustment in people formerly married or cohabiting, and moderators of those trajectories. A convenience sample of 303 recently separated individuals (169 women; 134 men) completed assessments of their emotional attachment to the former partner, loneliness, psychological distress, and coparenting conflict at two time points 6 months apart. Multilevel modeling of the overlapping multicohort design was used to estimate the trajectories of these different aspects of adjustment as a function of time since separation, marital status, gender, presence of children from the relationship, who initiated separation, social support, and anxious attachment. Attachment to the former partner, loneliness, and psychological distress were initially high but improved markedly across the 2 years after separation, but coparenting conflict was high and stable. Adjustment problems were similar in men and women, and in those formerly married or cohabiting, except that reported coparenting conflict was higher in men than women. Low social support and high anxious attachment predicted persistent attachment to the former partner, loneliness, and psychological distress. Coparenting conflict is a common, chronic problem for many separated individuals, and individuals with certain psychological vulnerabilities also experience chronic personal distress. © FPI, Inc.

  10. Two-microphone separation of speech mixtures. (United States)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan; Kjems, Ulrik


    Separation of speech mixtures, often referred to as the cocktail party problem, has been studied for decades. In many source separation tasks, the separation method is limited by the assumption of at least as many sensors as sources. Further, many methods require that the number of signals within the recorded mixtures be known in advance. In many real-world applications, these limitations are too restrictive. We propose a novel method for underdetermined blind source separation using an instantaneous mixing model which assumes closely spaced microphones. Two source separation techniques have been combined, independent component analysis (ICA) and binary time - frequency (T-F) masking. By estimating binary masks from the outputs of an ICA algorithm, it is possible in an iterative way to extract basis speech signals from a convolutive mixture. The basis signals are afterwards improved by grouping similar signals. Using two microphones, we can separate, in principle, an arbitrary number of mixed speech signals. We show separation results for mixtures with as many as seven speech signals under instantaneous conditions. We also show that the proposed method is applicable to segregate speech signals under reverberant conditions, and we compare our proposed method to another state-of-the-art algorithm. The number of source signals is not assumed to be known in advance and it is possible to maintain the extracted signals as stereo signals.

  11. Investigation of bacteremia after separator placement

    Directory of Open Access Journals (Sweden)

    Anjuman Preet Kaur Dua


    Full Text Available Background: Simple orthodontic procedure such as separator placement can be associated with the occurrence of transient bacteraemia. Use of clorhexidine before separator placement has been recommended as a measure to decrease the bacteraemia. Aim: The purpose of this study was to detect the presence of transient bacteremia after separator placement following use of 0.2% chlorhexidine gluconate mouthwash. Methodology: The study group consisted of 27 adult patients who reported for orthodontic treatment (18 males and 9 females. The patients were asked to rinse their mouth for 60 sec with 15 mL of 0.2% chlorhexidine gluconate mouthwash before the separator placement. An aseptic technique was used to draw out 5 ml of blood was from either the left or right antecubital fossa immediately before orthodontic separator placement (as control group, and the second 5 ml sample was taken 1–2 min after the placement of separators mesial and distal to all the first molars. All the blood samples were inoculated into culture bottles containing Brain Heart Infusion and incubated aerobically for 7 days. Media used for bacterial growth is chocolate agar and MacConkey agar. Results: From a total of 27 patients and 54 samples, none of the sample was found positive for bacteremia. Conclusion: This study demonstrated that there is no bacteremia after the placement of separators following the use of chlorhexidine mouthwash.

  12. The separation of pygopagus conjoined twins with fused spinal cords and imperforate anus

    Directory of Open Access Journals (Sweden)

    Barrett P. Cromeens


    Full Text Available Each set of conjoined twins has specific anatomic features dictating unique challenges to separation. Overcoming these challenges requires creative solutions that necessitate interdisciplinary collaboration. We present a unique case of pygopagus conjoined twins with fused spinal cords, imperforate anus without fistula, and a single anal sphincter complex. Separation included the use of novel applications of 3D printing and neurophysiologic monitoring. The 3D print helped to clarify the complex anatomy and facilitate communication during planning sessions. The neurophysiologic monitoring helped to distinguish a plane of separation for the spinal cords as well as the shared anal sphincter. Implementing these technologies and thus successfully separating these twins safely required a multidisciplinary team that extended beyond clinical specialties.

  13. Separation as a suicide risk factor. (United States)

    Wyder, Marianne; Ward, Patrick; De Leo, Diego


    Marital separation (as distinct from divorce) is rarely researched in the suicidological literature. Studies usually report on the statuses of 'separated' and 'divorced' as a combined category, possibly because demographic registries are not able to identify separation reliably. However, in most countries divorce only happens once the process of separation has settled which, in most cases, occurs a long time after the initial break-up. It has been hypothesised that separation might carry a far greater risk of suicide than divorce. The present study investigates the impact of separation on suicide risk by taking into account the effects of age and gender. The incidence of suicide associated with marital status, age and gender was determined by comparing the Queensland Suicide Register (a large dataset of all suicides in Queensland from 1994 to 2004) with the QLD population through two different census datasets: the Registered Marital Status and the Social Marital Status. These two registries permit the isolation of the variable 'separated' with great reliability. During the examined period, 6062 persons died by suicide in QLD (an average of 551 cases per year), with males outnumbering females by four to one. For both males and females separation created a risk of suicide at least 4 times higher than any other marital status. The risk was particularly high for males aged 15 to 24 (RR 91.62). This study highlights a great variation in the incidence of suicide by marital status, age and gender, which suggests that these variables should not be studied in isolation. Furthermore, particularly in younger males, separation appears to be strongly associated with the risk of suicide.

  14. New anion-exchange polymers for improved separations

    Energy Technology Data Exchange (ETDEWEB)

    Jarvinen, G.D.; Barr, M.E.; Marsh, S.F.


    Objective is to improve the understanding of how the structure of a new class of anion-exchange polymers controls the binding of anionic actinide complexes from solution. This is needed to develop practical separation systems that will reduce the cost of actinide processing operations within the DOE complex. In addition anion exchange is widely used in industry. Several new series of bifunctional anion- exchange polymers have been designed, synthesized, and tested for removing Pu(IV), Am(III), and U(VI) from nitric acid. The polymers contain a pyridinium site derived from the host poly(4-vinylpyridine) and a second cationic site attached through a chain of 2 to 6 methylene groups. The new polymers removed Pu four to ten times more efficiently than the best commercial materials.

  15. Post-separation families: Residential arrangements and everyday life of separated parents and their children

    NARCIS (Netherlands)

    Bakker, W.


    This dissertation is about post-separation families, their residential arrangements and the organization and practising of their everyday post-separation (family) life. Divorce and separation are common life events in most Western countries. In the Netherlands, 30% of all children under age 18

  16. Study Of Phase Separation In Glass (United States)

    Neilson, George F.; Weinberg, Michael C.; Smith, Gary L.


    Report describes an experimental study of effect of hydroxide content on phase separation in soda/silica glasses. Ordinary and gel glasses melted at 1,565 degree C, and melts stirred periodically. "Wet" glasses produced by passing bubbles of N2 saturated with water through melts; "dry" glasses prepared in similar manner, except N2 dried before passage through melts. Analyses of compositions of glasses performed by atomic-absorption and index-of-refraction measurements. Authors conclude hydroxide speeds up phase separation, regardless of method (gel or ordinary) by which glass prepared. Eventually helps material scientists to find ways to control morphology of phase separation.

  17. A Vortex Contactor for Carbon Dioxide Separations

    Energy Technology Data Exchange (ETDEWEB)

    Raterman, Kevin Thomas; Mc Kellar, Michael George; Turner, Terry Donald; Podgorney, Anna Kristine; Stacey, Douglas Edwin; Stokes, B.; Vranicar, J.


    Many analysts identify carbon dioxide (CO2) capture and separation as a major roadblock in efforts to cost effectively mitigate greenhouse gas emissions via sequestration. An assessment 4 conducted by the International Energy Agency (IEA) Greenhouse Gas Research and Development Programme cited separation costs from $35 to $264 per tonne of CO2 avoided for a conventional coal fired power plant utilizing existing capture technologies. Because these costs equate to a greater than 40% increase in current power generation rates, it appears obvious that a significant improvement in CO2 separation technology is required if a negative impact on the world economy is to be avoided.

  18. Marital Separation and Lethal Male Partner Violence. (United States)

    Ellis, Desmond


    Findings reported by many researchers indicate that the association between marital separation and intimate partner femicide has achieved the status of a sociological empirical generalization. The primary objective of this article is to contribute toward the cumulative development of a conflict theoretic explanation of separation- associated femicide by creating and testing a deductive conflict resolution theory that explains the empirical generalization. The causal mechanism identified in the theory is the intensity of conflict that increases with participation in adversarial and separation and divorce proceedings. Interventions logically derived from the theory are presented in the penultimate segment. Limitations are identified in the concluding segment. © The Author(s) 2016.

  19. Phase separator safety valve blow-off.

    CERN Multimedia

    G. Perinic


    The fast discharge of the CMS solenoid leads to a pressure rise in the phase separator. On August 28th, a fast discharge was triggered at a current level of 19.1 kA. The pressure in the phase separator increased up to the set pressure of the safety valve and some helium was discharged. In consequence of this and prevoious similar observations the liquid helium level in the phase separator has been reduced from 60% to 50% and later to 45% in order to reduce the helium inventory in the magnet.

  20. Transform domain steganography with blind source separation (United States)

    Jouny, Ismail


    This paper applies blind source separation or independent component analysis for images that may contain mixtures of text, audio, or other images for steganography purposes. The paper focuses on separating mixtures in the transform domain such as Fourier domain or the Wavelet domain. The study addresses the effectiveness of steganography when using linear mixtures of multimedia components and the ability of standard blind sources separation techniques to discern hidden multimedia messages. Mixing in the space, frequency, and wavelet (scale) domains is compared. Effectiveness is measured using mean square error rate between original and recovered images.

  1. Numerical simulation of multiphase flow in ventilation mill and channel with louvers and centrifugal separator


    Kozic Mirko S.; Ristic Slavica S.; Puharic Mirjana A.; Katavic Boris T.


    This paper presents the results of numerical flow simulation in ventilation mill of Kostolac B power plant, where louvers and centrifugal separator with adjustable blade angle are used. Numerical simulations of multiphase flow were performed using the Euler-Euler and Euler-Lagrange approach of ANSYS FLUENT software package. The results of numerical simulations are compared with measurements in the mill for both types of separators. Due to very complex geometry and large number of the gr...

  2. Wet separation processes as method to separate limestone and oil shale (United States)

    Nurme, Martin; Karu, Veiko


    Biggest oil shale industry is located in Estonia. Oil shale usage is mainly for electricity generation, shale oil generation and cement production. All these processes need certain quality oil shale. Oil shale seam have interlayer limestone layers. To use oil shale in production, it is needed to separate oil shale and limestone. A key challenge is find separation process when we can get the best quality for all product types. In oil shale separation typically has been used heavy media separation process. There are tested also different types of separation processes before: wet separation, pneumatic separation. Now oil shale industry moves more to oil production and this needs innovation methods for separation to ensure fuel quality and the changes in quality. The pilot unit test with Allmineral ALLJIG have pointed out that the suitable new innovation way for oil shale separation can be wet separation with gravity, where material by pulsating water forming layers of grains according to their density and subsequently separates the heavy material (limestone) from the stratified material (oil shale)bed. Main aim of this research is to find the suitable separation process for oil shale, that the products have highest quality. The expected results can be used also for developing separation processes for phosphorite rock or all others, where traditional separation processes doesn't work property. This research is part of the study Sustainable and environmentally acceptable Oil shale mining No. 3.2.0501.11-0025 and the project B36 Extraction and processing of rock with selective methods -;

  3. Towards Formal Verification of a Separation Microkernel (United States)

    Butterfield, Andrew; Sanan, David; Hinchey, Mike


    The best approach to verifying an IMA separation kernel is to use a (fixed) time-space partitioning kernel with a multiple independent levels of separation (MILS) architecture. We describe an activity that explores the cost and feasibility of doing a formal verification of such a kernel to the Common Criteria (CC) levels mandated by the Separation Kernel Protection Profile (SKPP). We are developing a Reference Specification of such a kernel, and are using higher-order logic (HOL) to construct formal models of this specification and key separation properties. We then plan to do a dry run of part of a formal proof of those properties using the Isabelle/HOL theorem prover.

  4. Method and apparatus for separating materials magnetically (United States)

    Hise, Jr., Eugene C.; Holman, Allen S.


    Magnetic and non-magnetic materials are separated by passing stream thereof past coaxial current-carrying coils which produce a magnetic field wherein intensity varies sharply with distance radially of the axis of the coils.


    Watt, G.W.


    An tmproved method is described for separating plutonium hydroxide from bismuth hydroxide. The end product of the bismuth phosphate processes for the separation amd concentration of plutonium is a inixture of bismuth hydroxide amd plutonium hydroxide. It has been found that these compounds can be advantageously separated by treatment with a reducing agent having a potential sufficient to reduce bismuth hydroxide to metalltc bisinuth but not sufficient to reduce the plutonium present. The resulting mixture of metallic bismuth and plutonium hydroxide can then be separated by treatment with a material which will dissolve plutonium hydroxide but not metallic bismuth. Sodiunn stannite is mentioned as a preferred reducing agent, and dilute nitric acid may be used as the separatory solvent.

  6. On the Maximum Separation of Visual Binaries

    Indian Academy of Sciences (India)


    minimum) angular separation ρmax(ρmin), the corresponding apparent position angles (|ρmax , |ρmin) and the individual masses of visual binary systems. The algorithm uses Reed's formulae (1984) for the masses, and a ...

  7. Dielectrophoretic separation of platelets for medical application (United States)

    Ismail, N. S.; Ong, N. R.; Aziz, M. H. A.; Alcai, J. B.; Sauli, Z.


    The need for efficient cell separation in many biological and medical application, has led to the recent development of numerous microscale separation. This paper described the dielectrophoresis in microfluidic-based cell separation technique which is used to separate platelets from red blood cells (RBCs) applied in medical application. COMSOL software was used to perform the simulations. Based on the results of the simulation obtained, it was deduced that the four parameters (electric potential, velocity, pressure and particle trajectories) influenced the DEP process. Velocity and pressure were two inter-related parameters whereby when the velocity increased at the inlet, the pressure decreased and vice versa. Most important, without dielectrophoretic force present, the whole process would be a failure.

  8. Residential mobility and migration of the separated

    Directory of Open Access Journals (Sweden)

    Maarten van Ham


    Full Text Available Separation is known to have a disruptive effect on the housing careers of those involved, mainly because a decrease in resources causes (temporary downward moves on the housing ladder. Little is known about the geographies of the residential mobility behaviour of the separated. Applying a hazard analysis to retrospective life-course data for the Netherlands, we investigate three hypotheses: individuals who experienced separation move more often than do steady singles and people in intact couple relationships, they are less likely to move over long distances, and they move more often to cities than people in intact couple relationships. The results show that separation leads to an increase in mobility, to moves over short distance for men with children, and to a prevalence of the city as a destination of moves.

  9. Robust Polymer Composite Membranes for Hydrogen Separation

    Energy Technology Data Exchange (ETDEWEB)



    This factsheet describes a research project whose primary goal is to achieve a major improvement in the combined economics and performance of polymenzimidazole-based (PBI) membrane technology in the application of hydrogen separation from a syngas stream.

  10. Tunable molecular separation by nanoporous membranes (United States)

    Wang, Zhengbang; Knebel, Alexander; Grosjean, Sylvain; Wagner, Danny; Bräse, Stefan; Wöll, Christof; Caro, Jürgen; Heinke, Lars


    Metal-organic frameworks offer tremendous potential for efficient separation of molecular mixtures. Different pore sizes and suitable functionalizations of the framework allow for an adjustment of the static selectivity. Here we report membranes which offer dynamic control of the selectivity by remote signals, thus enabling a continuous adjustment of the permeate flux. This is realized by assembling linkers containing photoresponsive azobenzene-side-groups into monolithic, crystalline membranes of metal-organic frameworks. The azobenzene moieties can be switched from the trans to the cis configuration and vice versa by irradiation with ultraviolet or visible light, resulting in a substantial modification of the membrane permeability and separation factor. The precise control of the cis:trans azobenzene ratio, for example, by controlled irradiation times or by simultaneous irradiation with ultraviolet and visible light, enables the continuous tuning of the separation. For hydrogen:carbon-dioxide, the separation factor of this smart membrane can be steplessly adjusted between 3 and 8.

  11. Electron beam control for barely separated beams (United States)

    Douglas, David R.; Ament, Lucas J. P.


    A method for achieving independent control of multiple beams in close proximity to one another, such as in a multi-pass accelerator where coaxial beams are at different energies, but moving on a common axis, and need to be split into spatially separated beams for efficient recirculation transport. The method for independent control includes placing a magnet arrangement in the path of the barely separated beams with the magnet arrangement including at least two multipole magnets spaced closely together and having a multipole distribution including at least one odd multipole and one even multipole. The magnetic fields are then tuned to cancel out for a first of the barely separated beams to allow independent control of the second beam with common magnets. The magnetic fields may be tuned to cancel out either the dipole component or tuned to cancel out the quadrupole component in order to independently control the separate beams.

  12. Two-Microphone Separation of Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan


    the recorded mixtures be known in advance. In many real-world applications, these limitations are too restrictive. We propose a novel method for underdetermined blind source separation using an instantaneous mixing model which assumes closely spaced microphones. Two source separation techniques have been...... combined, independent component analysis (ICA) and binary time–frequency (T–F) masking. By estimating binary masks from the outputs of an ICA algorithm, it is possible in an iterative way to extract basis speech signals from a convolutive mixture. The basis signals are afterwards improved by grouping...... similar signals. Using two microphones, we can separate, in principle, an arbitrary number of mixed speech signals. We show separation results for mixtures with as many as seven speech signals under instantaneous conditions. We also show that the proposed method is applicable to segregate speech signals...


    Energy Technology Data Exchange (ETDEWEB)

    Salih Ersayin


    A magnetic separator was designed to selectively separate fine-liberated magnetite. The conceptual design was simulated using CFD techniques. A separator tank was fabricated and a magnetic drum was used to capture magnetic particles. The initial tank design was modified to eliminate application oriented problems. The new separator was able to produce a fine product as a concentrate at relatively high feed rates. A plant simulation showed that such a device could lower circulating loads around ball mills by 16%, thereby creating room for a 5-8% increase in throughput at the same energy level. However, it was concluded that further improvements in terms of both size and mineral selectivity are needed to have a marketable product.

  14. Separation of Dalbergia stevensonii from Dalbergia tucurensis (United States)

    Micheal C. Wiemann; Flavio Ruffinatto


    Belize is home to two commercially important species of Dalbergia, D. stevensonii and D. tucurensis, whose overall appearance and wood anatomy are similar. D. stevensonii is protected from commercial harvesting, whereas D. tucurensis is not. Therefore, reliable methods for separating...

  15. Separation, identification and quantification of photosynthetic ...

    African Journals Online (AJOL)

    Thirty one photosynthetic pigments (chlorophylls, carotenoids and degradation products) from the seaweeds, Codium dwarkense, (Chlorophyta), , Laurencia obtusa , (Rhodophyta) and , Lobophora variegata, (Phaeophyta), were separated in a single-step procedure by reversed phase high-performance liquid ...

  16. Blind speech separation system for humanoid robot with FastICA for audio filtering and separation (United States)

    Budiharto, Widodo; Santoso Gunawan, Alexander Agung


    Nowadays, there are many developments in building intelligent humanoid robot, mainly in order to handle voice and image. In this research, we propose blind speech separation system using FastICA for audio filtering and separation that can be used in education or entertainment. Our main problem is to separate the multi speech sources and also to filter irrelevant noises. After speech separation step, the results will be integrated with our previous speech and face recognition system which is based on Bioloid GP robot and Raspberry Pi 2 as controller. The experimental results show the accuracy of our blind speech separation system is about 88% in command and query recognition cases.

  17. Recovery of ferrous and nonferrous metal from ASR by physical separation (United States)

    Kim, Min-gyu; Han, Oh-hyung; Park, Chul-hyun


    A recycle ratio of waste automobiles in Korea is low, compared to that of the advanced countries. Especially in its recycle, separation of automotive shredder residue (ASR), the residual fraction of approximate 25% obtained after dismantling and shredding from waste car, is needed. However ASR is cannot be effectively separated due to its heterogeneous materials and coated or laminated complexes and then is largely deposited in land-fill sites as waste. In this study ASR was separated by a series of physical processing operations such as comminution, air classification and magnetic separation and electrostatic separations. In particular it focuses on estimating the optimal conditions of magnetic and electrostatic separations for improving the separation efficiency of valuable ferrous and non-ferrous metals such as iron (Fe), aluminum, copper and etc. In magnetic separation, 91.5% Fe grade and 91% recovery could be obtained at conditions of particle size under 10mm and magnetic intensity of 400 gauss. In corona electrostatic separation for recovering nonferrous metals, a grade of 79.2% and recovery of 90.7% could be successfully achieved under conditions of -6mm particle size, 50kV electrode potential, 35rpm drum speed and 20 degree splitter position, respectively. Acknowledgments This study was supported by the R&D Center for Valuable Recycling (Global-Top R&BD Program) of the Ministry of Environment. (Project No. 2016002250001)

  18. Superconducting RF separator for Omega Spectrometer

    CERN Multimedia


    The photo shows an Nb-deflector for the superconducting RF separator ready for installation in its cryostat (visible at the back). Each deflector was about 3 m long. L. Husson and P. Skacel (Karlsruhe) stand on the left, A. Scharding (CERN) stands on the right. This particle separator, the result of a collaboration between the Gesellshaft für Kernforschung, Karlsruhe, and CERN was installed in the S1 beam line to Omega spectrometer. (See Annual Report 1977.)

  19. Waste Separations and Pretreatment Workshop report

    Energy Technology Data Exchange (ETDEWEB)

    Cruse, J.M. [Westinghouse Hanford Co., Richland, WA (United States); Harrington, R.A. [Kaiser Engineers Hanford Co., Richland, WA (United States); Quadrel, M.J. [Battelle Pacific Northwest Lab., Richland, WA (United States)


    This document provides the minutes from the Waste Separations and Pretreatment Workshop sponsored by the Underground Storage Tank-Integrated Demonstration in Salt Lake City, Utah, February 3--5, 1993. The Efficient Separations and Processing-Integrated Program and the Hanford Site Tank Waste Remediation System were joint participants. This document provides the detailed minutes, including responses to questions asked, an attendance list, reproductions of the workshop presentations, and a revised chart showing technology development activities.

  20. Electrolytic cell. [For separating anolyte and catholyte (United States)

    Bullock, J.S.; Hale, B.D.


    An apparatus is described for the separation of the anolyte and the catholyte during electrolysis. The electrolyte flows through an electrolytic cell between the oppositely charged electrodes. The cell is equipped with a wedge-shaped device, the tapered end being located between the electrodes on the effluent side of the cell. The wedge diverts the flow of the electrolyte to either side of the wedge, substantially separating the anolyte and the catholyte.