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Sample records for soluble organic matrices

  1. Solubility of crystalline organic compounds in high and low molecular weight amorphous matrices above and below the glass transition by zero enthalpy extrapolation.

    Science.gov (United States)

    Amharar, Youness; Curtin, Vincent; Gallagher, Kieran H; Healy, Anne Marie

    2014-09-10

    Pharmaceutical applications which require knowledge of the solubility of a crystalline compound in an amorphous matrix are abundant in the literature. Several methods that allow the determination of such data have been reported, but so far have only been applicable to amorphous polymers above the glass transition of the resulting composites. The current work presents, for the first time, a reliable method for the determination of the solubility of crystalline pharmaceutical compounds in high and low molecular weight amorphous matrices at the glass transition and at room temperature (i.e. below the glass transition temperature), respectively. The solubilities of mannitol and indomethacin in polyvinyl pyrrolidone (PVP) K15 and PVP K25, respectively were measured at different temperatures. Mixtures of undissolved crystalline solute and saturated amorphous phase were obtained by annealing at a given temperature. The solubility at this temperature was then obtained by measuring the melting enthalpy of the crystalline phase, plotting it as a function of composition and extrapolating to zero enthalpy. This new method yielded results in accordance with the predictions reported in the literature. The method was also adapted for the measurement of the solubility of crystalline low molecular weight excipients in amorphous active pharmaceutical ingredients (APIs). The solubility of mannitol, glutaric acid and adipic acid in both indomethacin and sulfadimidine was experimentally determined and successfully compared with the difference between their respective calculated Hildebrand solubility parameters. As expected from the calculations, the dicarboxylic acids exhibited a high solubility in both amorphous indomethacin and sulfadimidine, whereas mannitol was almost insoluble in the same amorphous phases at room temperature. This work constitutes the first report of the methodology for determining an experimentally measured solubility for a low molecular weight crystalline solute

  2. Soluble organic nutrient fluxes

    Science.gov (United States)

    Robert G. Qualls; Bruce L. Haines; Wayne Swank

    2014-01-01

    Our objectives in this study were (i) compare fluxes of the dissolved organic nutrients dissolved organic carbon (DOC), DON, and dissolved organic phosphorus (DOP) in a clearcut area and an adjacent mature reference area. (ii) determine whether concentrations of dissolved organic nutrients or inorganic nutrients were greater in clearcut areas than in reference areas,...

  3. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization

    Energy Technology Data Exchange (ETDEWEB)

    Ren Dongni; Li Zhuo; Gao Yonghua; Feng Qingling, E-mail: biomater@mail.tsinghua.edu.c [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2010-10-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH{sub 2} and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH{sub 2} and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  4. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization

    International Nuclear Information System (INIS)

    Ren Dongni; Li Zhuo; Gao Yonghua; Feng Qingling

    2010-01-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH 2 and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH 2 and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  5. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization.

    Science.gov (United States)

    Ren, Dongni; Li, Zhuo; Gao, Yonghua; Feng, Qingling

    2010-10-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH2 and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH2 and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  6. Two-Stage Crystallizer Design for High Loading of Poorly Water-Soluble Pharmaceuticals in Porous Silica Matrices

    OpenAIRE

    Leia Dwyer; Samir Kulkarni; Luzdary Ruelas; Allan Myerson

    2017-01-01

    While porous silica supports have been previously studied as carriers for nanocrystalline forms of poorly water-soluble active pharmaceutical ingredients (APIs), increasing the loading of API in these matrices is of great importance if these carriers are to be used in drug formulations. A dual-stage mixed-suspension, mixed-product removal (MSMPR) crystallizer was designed in which the poorly soluble API fenofibrate was loaded into the porous matrices of pore sizes 35 nm-300 nm in the first st...

  7. A Colorful Solubility Exercise for Organic Chemistry

    Science.gov (United States)

    Shugrue, Christopher R.; Mentzen, Hans H., II; Linton, Brian R.

    2015-01-01

    A discovery chemistry laboratory has been developed for the introductory organic chemistry student to investigate the concepts of polarity, miscibility, solubility, and density. The simple procedure takes advantage of the solubility of two colored dyes in a series of solvents or solvent mixtures, and the diffusion of colors can be easily…

  8. Soluble organic nanotubes for catalytic systems

    Science.gov (United States)

    Xiong, Linfeng; Yang, Kunran; Zhang, Hui; Liao, Xiaojuan; Huang, Kun

    2016-03-01

    In this paper, we report a novel method for constructing a soluble organic nanotube supported catalyst system based on single-molecule templating of core-shell bottlebrush copolymers. Various organic or metal catalysts, such as sodium prop-2-yne-1-sulfonate (SPS), 1-(2-(prop-2-yn-1-yloxy)ethyl)-1H-imidazole (PEI) and Pd(OAc)2 were anchored onto the tube walls to functionalize the organic nanotubes via copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. Depending on the ‘confined effect’ and the accessible cavity microenvironments of tubular structures, the organic nanotube catalysts showed high catalytic efficiency and site-isolation features. We believe that the soluble organic nanotubes will be very useful for the development of high performance catalyst systems due to their high stability of support, facile functionalization and attractive textural properties.

  9. Soluble organic nanotubes for catalytic systems.

    Science.gov (United States)

    Xiong, Linfeng; Yang, Kunran; Zhang, Hui; Liao, Xiaojuan; Huang, Kun

    2016-03-18

    In this paper, we report a novel method for constructing a soluble organic nanotube supported catalyst system based on single-molecule templating of core–shell bottlebrush copolymers. Various organic or metal catalysts, such as sodium prop-2-yne-1-sulfonate (SPS), 1-(2-(prop-2-yn-1-yloxy)ethyl)-1H-imidazole (PEI) and Pd(OAc)2 were anchored onto the tube walls to functionalize the organic nanotubes via copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. Depending on the 'confined effect' and the accessible cavity microenvironments of tubular structures, the organic nanotube catalysts showed high catalytic efficiency and site-isolation features. We believe that the soluble organic nanotubes will be very useful for the development of high performance catalyst systems due to their high stability of support, facile functionalization and attractive textural properties.

  10. Matrices for Sensors from Inorganic, Organic, and Biological Nanocomposites

    Directory of Open Access Journals (Sweden)

    Eugenia Pechkova

    2011-08-01

    Full Text Available Matrices and sensors resulting from inorganic, organic and biological nanocomposites are presented in this overview. The term nanocomposite designates a solid combination of a matrix and of nanodimensional phases differing in properties from the matrix due to dissimilarities in structure and chemistry. The nanoocomposites chosen for a wide variety of health and environment sensors consist of Anodic Porous Allumina and P450scc, Carbon nanotubes and Conductive Polymers, Langmuir Blodgett Films of Lipases, Laccases, Cytochromes and Rhodopsins, Three-dimensional Nanoporous Materials and Nucleic Acid Programmable Protein Arrays.

  11. Characterization of Soluble Organics in Produced Water

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, D.T.

    2002-01-16

    Soluble organics in produced water and refinery effluents represent treatment problems for the petroleum industry. Neither the chemistry involved in the production of soluble organics nor the impact of these chemicals on total effluent toxicity is well understood. The U.S. Department of Energy provides funding for Oak Ridge National Laboratory (ORNL) to support a collaborative project with Shell, Chevron, Phillips, and Statoil entitled ''Petroleum and Environmental Research Forum project (PERF 9844: Manage Water-Soluble Organics in Produced Water''). The goal of this project, which involves characterization and evaluation of these water-soluble compounds, is aimed at reducing the future production of such contaminants. To determine the effect that various drilling conditions might have on water-soluble organics (WSO) content in produced water, a simulated brine water containing the principal inorganic components normally found in Gulf of Mexico (GOM) brine sources was prepared. The GOM simulant was then contacted with as-received crude oil from a deep well site to study the effects of water cut, produced-water pH, salinity, pressure, temperature, and crude oil sources on the type and content of the WSO in produced water. The identities of individual semivolatile organic compounds (SVOCs) were determined in all as-received crude and actual produced water samples using standard USEPA Method (8270C) protocol. These analyses were supplemented with the more general measurements of total petroleum hydrocarbon (TPH) content in the gas (C{sub 6}-C{sub 10}), diesel (C{sub 10}-C{sub 20}), and oil (C{sub 20}-C{sub 28}) carbon ranges as determined by both gas chromatographic (GC) and infrared (IR) analyses. An open liquid chromatographic procedure was also used to differentiate the saturated hydrocarbon, aromatic hydrocarbon, and polar components within the extractable TPH. Inorganic constituents in the produced water were analyzed by ion

  12. Two-Stage Crystallizer Design for High Loading of Poorly Water-Soluble Pharmaceuticals in Porous Silica Matrices

    Directory of Open Access Journals (Sweden)

    Leia Dwyer

    2017-05-01

    Full Text Available While porous silica supports have been previously studied as carriers for nanocrystalline forms of poorly water-soluble active pharmaceutical ingredients (APIs, increasing the loading of API in these matrices is of great importance if these carriers are to be used in drug formulations. A dual-stage mixed-suspension, mixed-product removal (MSMPR crystallizer was designed in which the poorly soluble API fenofibrate was loaded into the porous matrices of pore sizes 35 nm–300 nm in the first stage, and then fed to a second stage in which the crystals were further grown in the pores. This resulted in high loadings of over 50 wt % while still producing nanocrystals confined to the pores without the formation of bulk-sized crystals on the surface of the porous silica. The principle was extended to another highly insoluble API, griseofulvin, to improve its loading in porous silica in a benchtop procedure. This work demonstrates a multi-step crystallization principle API in porous silica matrices with loadings high enough to produce final dosage forms of these poorly water-soluble APIs.

  13. pH-independent release of propranolol hydrochloride from HPMC-based matrices using organic acids

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available Background and purpose of the study: Propranolol HCl, a widely used drug in the treatment of cardiac arrhythmias and hypertension, is a weak basic drug with pH-dependent solubility that may show release problems from sustained release dosage forms at higher pH of small intestine. This might decrease drug bioavailability and cause variable oral absorption. Preparation of a sustained release matrix system with a pH-independent release profile was the aim of the present study. Methods: Three types of organic acids namely tartaric, citric and fumaric acid in the concentrations of 5, 10 and 15 % were added to the matrices prepared by hydroxypropyl methylcellulose (HPMC and dicalcium phosphate. The drug release studies were carried out at pH 1.2 and pH 6.8 separately and mean dissolution time (MDT as well as similarity factor (¦2 were calculated for all formulations. Results and discussion: It was found that incorporation of 5 and 10 % tartaric acid in tablet formulations with 30 % HPMC resulted in a suitable pH-independent release profiles with significant higher ¦2 values (89.9 and 87.6 respectively compared to acid free tablet (58.03. The other two acids did not show the desirable effects. It seems that lower pKa of tartaric acid accompanied by its higher solubility were the main factors in the achievement of pH-independent release profiles.

  14. Both solubility and chemical stability of curcumin are enhanced by solid dispersion in cellulose derivative matrices.

    Science.gov (United States)

    Li, Bin; Konecke, Stephanie; Wegiel, Lindsay A; Taylor, Lynne S; Edgar, Kevin J

    2013-10-15

    Amorphous solid dispersions (ASD) of curcumin (Cur) in cellulose derivative matrices, hydroxypropylmethylcellulose acetate succinate (HPMCAS), carboxymethylcellulose acetate butyrate (CMCAB), and cellulose acetate adipate propionate (CAAdP) were prepared in order to investigate the structure-property relationship and identify polymer properties necessary to effectively increase Cur aqueous solution concentration. XRD results indicated that all investigated solid dispersions were amorphous, even at a 9:1 Cur:polymer ratio. Both stability against crystallization and Cur solution concentration from these ASDs were significantly higher than those from physical mixtures and crystalline Cur. Remarkably, curcumin was also stabilized against chemical degradation in solution. Chemical stabilization was polymer-dependent, with stabilization in CAAdP>CMCAB>HPMCAS>PVP, while matrices enhanced solution concentration as PVP>HPMCAS>CMCAB≈CAAdP. HPMCAS/Cur dispersions have useful combinations of pH-triggered release profile, chemical stabilization, and strong enhancement of Cur solution concentration. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A new method for the analysis of soluble and insoluble oxalate in pulp and paper matrices

    CSIR Research Space (South Africa)

    Sithole, Bruce

    2013-11-01

    Full Text Available A novel method has been developed for determining soluble and insoluble forms of oxalate in pulp and paper samples by ion chromatography. Methanesulphonic acid is used to dissolve insoluble oxalate, and total oxalate is then determined by ion...

  16. The Development of Novel Nanodiamond Based MALDI Matrices for the Analysis of Small Organic Pharmaceuticals

    Science.gov (United States)

    Chitanda, Jackson M.; Zhang, Haixia; Pahl, Erica; Purves, Randy W.; El-Aneed, Anas

    2016-10-01

    The utility of novel functionalized nanodiamonds (NDs) as matrices for matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) is described herein. MALDI-MS analysis of small organic compounds (<1000 Da) is typically complex because of interferences from numerous cluster ions formed when using conventional matrices. To expand the use of MALDI for the analysis of small molecules, novel matrices were designed by covalently linking conventional matrices (or a lysine moiety) to detonated NDs. Four new functionalized NDs were evaluated for their ionization capabilities using five pharmaceuticals with varying molecular structures. Two ND matrices were able to ionize all tested pharmaceuticals in the negative ion mode, producing the deprotonated ions [M - H]-. Ion intensity for target analytes was generally strong with enhanced signal-to-noise ratios compared with conventional matrices. The negative ion mode is of great importance for biological samples as interference from endogenous compounds is inherently minimized in the negative ion mode. Since the molecular structures of the tested pharmaceuticals did not suggest that negative ion mode would be preferable, this result magnifies the importance of these findings. On the other hand, conventional matrices primarily facilitated the ionization as expected in the positive ion mode, producing either the protonated molecules [M + H]+ or cationic adducts (typically producing complex spectra with numerous adduct peaks). The data presented in this study suggests that these matrices may offer advantages for the analysis of low molecular weight pharmaceuticals/metabolites.

  17. Binary systems solubilities of inorganic and organic compounds

    CERN Document Server

    Stephen, H

    1963-01-01

    Solubilities of Inorganic and Organic Compounds, Volume 1: Binary Systems, Part 1 is part of an approximately 5,500-page manual containing a selection from the International Chemical Literature on the Solubilities of Elements, Inorganic Compounds, Metallo-organic and Organic Compounds in Binary, Ternary and Multi-component Systems. A careful survey of the literature in all languages by a panel of scientists specially appointed for the task by the U.S.S.R. Academy of Sciences, Moscow, has made the compilation of this work possible. The complete English edition in five separately bound volumes w

  18. Simultaneous determination of water-soluble vitamins in selected food matrices by liquid chromatography/electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Gentili, Alessandra; Caretti, Fulvia; D'Ascenzo, Giuseppe; Marchese, Stefano; Perret, Daniela; Di Corcia, Daniele; Rocca, Lucia Mainero

    2008-07-01

    A rapid, simple and sensitive method based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) with an electrospray ionization (ESI) source for the simultaneous analysis of fourteen water-soluble vitamins (B1, B2, two B3 vitamers, B5, five B6 vitamers, B8, B9, B12 and C) in various food matrices, i.e. maize flour, green and golden kiwi and tomato pulp, is presented here. Analytes were separated by ion-suppression reversed-phase liquid chromatography in less than 10 min and detected in positive ion mode. Sensitivity and specificity of this method allowed two important results to be achieved: (i) limits of detection of the analytes at ng g(-1) levels (except for vitamin C); (ii) development of a rapid sample treatment that minimizes analyte exposition to light, air and heat, eliminating any step of extract concentration. Analyte recovery depended on the type of matrix. In particular, recovery of the analytes in maize flour was > or =70%, with the exception of vitamin C, pyridoxal-5'-phosphate and vitamin B9 (ca 40%); with tomato pulp, recovery was > or =64%, except for vitamin C (41%); with kiwi, recovery was > or =73%, except for nicotinamide (ca. 30%).

  19. Subcritical-Water Extraction of Organics from Solid Matrices

    Science.gov (United States)

    Amashukeli, Xenia; Grunthaner, Frank; Patrick, Steven; Kirby, James; Bickler, Donald; Willis, Peter; Pelletier, Christine; Bryson, Charles

    2009-01-01

    An apparatus for extracting organic compounds from soils, sands, and other solid matrix materials utilizes water at subcritical temperature and pressure as a solvent. The apparatus, called subcritical water extractor (SCWE), is a prototype of subsystems of future instrumentation systems to be used in searching for organic compounds as signs of past or present life on Mars. An aqueous solution generated by an apparatus like this one can be analyzed by any of a variety of established chromatographic or spectroscopic means to detect the dissolved organic compound( s). The apparatus can be used on Earth: indeed, in proof-of-concept experiments, SCWE was used to extract amino acids from soils of the Atacama Desert (Chile), which was chosen because the dryness and other relevant soil conditions there approximate those on Mars. The design of the apparatus is based partly on the fact that the relative permittivity (also known as the dielectric constant) of liquid water varies with temperature and pressure. At a temperature of 30 C and a pressure of 0.1 MPa, the relative permittivity of water is 79.6, due to the strong dipole-dipole electrostatic interactions between individual molecular dipoles. As the temperature increases, increasing thermal energy causes increasing disorientation of molecular dipoles, with a consequent decrease in relative permittivity. For example, water at a temperature of 325 C and pressure of 20 MPa has a relative permittivity of 17.5, which is similar to the relative permittivities of such nonpolar organic solvents as 1-butanol (17.8). In the operation of this apparatus, the temperature and pressure of water are adjusted so that the water can be used in place of commonly used organic solvents to extract compounds that have dissimilar physical and chemical properties.

  20. OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER

    Energy Technology Data Exchange (ETDEWEB)

    Klasson, KT

    2002-03-14

    This project was an extension of previous research to improve the applicability of ozonation and will help address the petroleum-industry problem of treating produced water containing soluble organics. The goal of this project was to maximize oxidation of hexane-extractable organics during a single-pass operation. The project investigated: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Several types of methodologies for treatment of soluble organics in synthetic and actual produced waters have been performed. The technologies tested may be categorized as follows: (1) Destruction via sonochemical oxidation at different pH, salt concentration, ultraviolet irradiation, and ferrous iron concentrations. (2) Destruction via ozonation at different pH, salt concentration, hydrogen peroxide concentrations, ultraviolet irradiation, temperature, and reactor configurations.

  1. The effect of pH and ionic strength of dissolution media on in-vitro release of two model drugs of different solubilities from HPMC matrices.

    Science.gov (United States)

    Asare-Addo, Kofi; Conway, Barbara R; Larhrib, Hassan; Levina, Marina; Rajabi-Siahboomi, Ali R; Tetteh, John; Boateng, Joshua; Nokhodchi, Ali

    2013-11-01

    The evaluation of the effects of different media ionic strengths and pH on the release of hydrochlorothiazide, a poorly soluble drug, and diltiazem hydrochloride, a cationic and soluble drug, from a gel forming hydrophilic polymeric matrix was the objective of this study. The drug to polymer ratio of formulated tablets was 4:1. Hydrochlorothiazide or diltiazem HCl extended release (ER) matrices containing hypromellose (hydroxypropyl methylcellulose (HPMC)) were evaluated in media with a pH range of 1.2-7.5, using an automated USP type III, Bio-Dis dissolution apparatus. The ionic strength of the media was varied over a range of 0-0.4M to simulate the gastrointestinal fed and fasted states and various physiological pH conditions. Sodium chloride was used for ionic regulation due to its ability to salt out polymers in the midrange of the lyotropic series. The results showed that the ionic strength had a profound effect on the drug release from the diltiazem HCl K100LV matrices. The K4M, K15M and K100M tablets however withstood the effects of media ionic strength and showed a decrease in drug release to occur with an increase in ionic strength. For example, drug release after the 1h mark for the K100M matrices in water was 36%. Drug release in pH 1.2 after 1h was 30%. An increase of the pH 1.2 ionic strength to 0.4M saw a reduction of drug release to 26%. This was the general trend for the K4M and K15M matrices as well. The similarity factor f2 was calculated using drug release in water as a reference. Despite similarity occurring for all the diltiazem HCl matrices in the pH 1.2 media (f2=64-72), increases of ionic strength at 0.2M and 0.4M brought about dissimilarity. The hydrochlorothiazide tablet matrices showed similarity at all the ionic strength tested for all polymers (f2=56-81). The values of f2 however reduced with increasing ionic strengths. DSC hydration results explained the hydrochlorothiazide release from their HPMC matrices. There was an increase in

  2. Radiation-induced transformations of isolated organic molecules in solid rare gas matrices

    International Nuclear Information System (INIS)

    Feldman, V.I.

    1998-01-01

    Complete text of publication follows. The studies of radiation-chemical behaviour of isolated organic molecules in rigid inert media are of considerable interest for radiation chemistry and general structural chemistry. Previous efforts were limited to the ESR studies of radicals resulting from some small hydrocarbon molecules in frozen rare gas solutions. Recently, we developed an approach to the radiation chemistry of isolated organic molecules using classic matrix isolation procedure for sample preparation and a combination of ESR and IR spectroscopy for characterization of paramagnetic and diamagnetic species resulting form electron irradiation or organic molecules in solid rare gas matrices at 10-15 K. The results obtained reveal high efficiency of energy transfer from rare gas matrix to organic molecules. The total radiation-chemical yields of degradation of organic molecules in argon and xenon matrices were measured directly by IR spectroscopy. The studies of the effect of electron scavengers on the radiolysis of organic molecules in solid rare gases show that the main primary process is positive hole transfer from matrix to additive molecule. ESR spectra of a number of radical cations (alkanes, ethers, arenes) were first characterized in a low-disturbing environment. It was found that the electronic characteristics (IP, polarizability) of the matrix used had crucial effect on trapping and degradation of primary organic radical cations. Using matrices with various IP provides an unique possibility to examine the chemical meaning of excess energy resulting from exothermic positive hole transfer, that is, to follow the fate of excited cations in condensed phase

  3. The Nanomechanics of Biomineralized Soft-Tissues and Organic Matrices

    Science.gov (United States)

    Bezares-Chavez, Jiddu

    The research reported on in this dissertation is concerned with the macro-molecular constitution and geometrical organization of the soft-tissue comprising the matrix of the nacreous portion of the shell of Haliotis rufescens, the Red abalone. Nacre is one of literally legions of intricate biomineralized structures that exist in nature and has long served as a paradigm for elegant and optimized structural de-sign. Biomineralization involves, inter alia, the uptake and synthesis of elements and compounds from the environment and their incorporation into highly optimized functional structures. Nacre has a structure described as a brick wall like with a matrix of biopolymer layers that are preformed and serve as a template into which nanocrystalline tiles of CaCO3 precipitate. The matrix, or what are known as inter-lamellar layers, are of particular interest as they impart both toughness and strength to the composite ceramic nacre structure. The work first involved a histochemical mapping of the macromolecular structure of the interlamellar layers; this revealed the locations of proteins and functional molecular groups that serve as nucleation sites for the ceramic tiles. Parallel studies on the nacre of Nautilus pompilius, the Chambered Nautilus, revealed the generality of the findings. Of particular interest was determining both the content and layout of chitin within these layers. In fact it was determined that chitin was organized as mostly unidirectional architecture of fibrils, with a certain fraction of fibrils laying at cross directions. Most remarkably, it was found that the fibrils possessed a very long range connectivity that spanned many tiles. This was determined by systematic atomic force (afm) and analytical optical histochemical microscopy. These findings were further verified by a unique form of mechanical testing whereby tensile testing was conducted on groups of interlamellar layers extracted from nacre. Mechanical testing led to a quantitative

  4. Design of modified xanthan mini-matrices for monitoring oral discharge of highly soluble Soluplus{sup ®}–glibenclamide dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Bakshi, Paromita; Sadhukhan, Sayantan; Maiti, Sabyasachi, E-mail: sabya245@rediffmail.com

    2015-09-01

    In this work, Soluplus{sup ®} was used as a hydrophilic carrier for the preparation of solid dispersion (SD) of a model BCS class II drug, glibenclamide by applying hot melting process and microwave irradiation in combination. Increasing the concentration of carrier relative to drug significantly increased the drug solubility, which corresponded to a maximum 75 fold increase at a drug:carrier ratio of 1:7. Scanning electron microscopy, differential scanning calorimetry, and x-ray diffraction analyses confirmed complete amorphization of the drug in SD. In animal study, about two fold reductions in hyperglycemic level were achieved by SD compared to pure drug. SD-loaded O-carboxymethyl xanthan mini-matrices controlled the release of drug into gastro-luminal fluid over longer duration. The drug release corroborated with pH-dependent swelling behavior of the matrices and approximated anomalous diffusion mechanism. This study proved the potential of Soluplus{sup ®}-based dispersion in improving the clinical performance of the drug, especially when embedded in modified xanthan mini-matrices. - Highlights: • Microwave-induced solid dispersion of glibenclamide was prepared using Soluplus®. • Solubility of drug corresponded to 75 fold increase at a drug:Soluplus® ratio of 1:7. • Thermal and x-ray analyses suggested amorphization of drug in solid dispersion. • About two fold reductions in hyperglycemic level were achieved by solid dispersion. • Modified xanthan gum showed potential in controlling anomalous transport of drug.

  5. Biochemical Composition and Assembly of Biosilica-associated Insoluble Organic Matrices from the Diatom Thalassiosira pseudonana.

    Science.gov (United States)

    Kotzsch, Alexander; Pawolski, Damian; Milentyev, Alexander; Shevchenko, Anna; Scheffel, André; Poulsen, Nicole; Shevchenko, Andrej; Kröger, Nils

    2016-03-04

    The nano- and micropatterned biosilica cell walls of diatoms are remarkable examples of biological morphogenesis and possess highly interesting material properties. Only recently has it been demonstrated that biosilica-associated organic structures with specific nanopatterns (termed insoluble organic matrices) are general components of diatom biosilica. The model diatom Thalassiosira pseudonana contains three types of insoluble organic matrices: chitin meshworks, organic microrings, and organic microplates, the latter being described in the present study for the first time. To date, little is known about the molecular composition, intracellular assembly, and biological functions of organic matrices. Here we have performed structural and functional analyses of the organic microrings and organic microplates from T. pseudonana. Proteomics analysis yielded seven proteins of unknown function (termed SiMat proteins) together with five known silica biomineralization proteins (four cingulins and one silaffin). The location of SiMat1-GFP in the insoluble organic microrings and the similarity of tyrosine- and lysine-rich functional domains identifies this protein as a new member of the cingulin protein family. Mass spectrometric analysis indicates that most of the lysine residues of cingulins and the other insoluble organic matrix proteins are post-translationally modified by short polyamine groups, which are known to enhance the silica formation activity of proteins. Studies with recombinant cingulins (rCinY2 and rCinW2) demonstrate that acidic conditions (pH 5.5) trigger the assembly of mixed cingulin aggregates that have silica formation activity. Our results suggest an important role for cingulins in the biogenesis of organic microrings and support the hypothesis that this type of insoluble organic matrix functions in biosilica morphogenesis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Melting Behavior of Organic Nanocrystals Grown in Sol-gel Matrices

    International Nuclear Information System (INIS)

    Sanz, N.; Boudet, A.; Ibanez, A.

    2002-01-01

    We have characterized the thermal stability of organic nanocrystals grown in the pores of sol-gel matrices. The structure has been measured with transmission electron microscopy (TEM) analysis. Depending on the nature of organic molecules and sol-gel matrices, we have modified the dye-matrix interactions and the interfacial structure between nanocrystals and gel-glasses. When the dye-matrix interactions are weak (Van der Waals' bonds), the corresponding interfacial structure observed by TEM is sharp and the nanocrystals melt below the bulk melting point. On the other hand, when the dye-matrix interactions are strong (hydrogen bonds), the interfacial structure is fuzzy and a great superheating of organic nanocrystals is observed in comparison to the bulk melting point of the dye

  7. Impact of fog processing on water soluble organic aerosols.

    Science.gov (United States)

    Tripathi, S. N.; Chakraborty, A.; Gupta, T.

    2017-12-01

    Fog is a natural meteorological phenomenon that occurs all around the world, and contains a substantial quantity of liquid water. Fog is generally seen as a natural cleansing agent but can also form secondary organic aerosols (SOA) via aqueous processing of ambient organics. Few field studies have reported elevated O/C ratio and SOA mass during or after fog events. However, mechanism behind aqueous SOA formation and its contribution to total organic aerosols (OA) still remains unclear. In this study we have tried to explore the impact of fog/aqueous processing on the characteristics of water soluble organic aerosols (WSOC), which to our knowledge has not been studied before. To assess this, both online (using HR-ToF-AMS) and offline (using a medium volume PM2.5 sampler and quartz filter) aerosol sampling were carried out at Kanpur, India from 15 December 2014 - 10 February 2015. Further, offline analysis of the aqueous extracts of the collected filters were carried out by AMS to characterize the water soluble OA (WSOA). Several (17) fog events occurred during the campaign and high concentrations of OA (151 ± 68 µg/m3) and WSOA (47 ± 19 µg/m3) were observed. WSOA/OA ratios were similar during fog (0.36 ± 0.14) and nofog (0.34 ± 0.15) periods. WSOA concentrations were also similar (slightly higher) during foggy (49 ± 18 µg/m3) and non-foggy periods (46 ± 20 µg/m3), in spite of fog scavenging. However, WSOA was more oxidized during foggy period (average O/C = 0.81) than non foggy periods (average O/C = 0.70). Like WSOA, OA was also more oxidized during foggy periods (average O/C = 0.64) than non foggy periods (average O/C = 0.53). During fog, WSOA to WIOA (water insoluble OA) ratios were higher (0.65 ± 0.16) compared to non foggy periods (0.56 ± 0.15). These observations clearly showed that WSOA become more dominant and processed during fog events, possibly due to the presence of fog droplets. This study highlights that fog processing of soluble organics

  8. Bismuth solubility through binding by various organic compounds and naturally occurring soil organic matter.

    Science.gov (United States)

    Murata, Tomoyoshi

    2010-01-01

    The present study was performed to examine the effects of soluble organic matter and pH on the solubility of Bi in relation to inference with the behavior of metallic Bi dispersed in soil and water environments using EDTA, citric acid, tartaric acid, L-cysteine, soil humic acids (HA), and dissolved organic matter (DOM) derived from the soil organic horizon. The solubility of Bi by citric acid, tartaric acid, L-cysteine, HA, and DOM showed pH dependence, while that by EDTA did not. Bi solubility by HA seemed to be related to the distribution of pKa (acid dissociation constant) values of acidic functional groups in their molecules. That is, HA extracted at pH 3.2 solubilized Bi preferentially in the acidic range, while HA extracted at pH 8.4 showed preferential solubilization at neutral and alkaline pH. This was related to the dissociation characteristics of functional groups, their binding capacity with Bi, and precipitation of Bi carbonate or hydroxides. In addition to the dissociation characteristics of functional groups, the unique structural configuration of the HA could also contribute to Bi-HA complex formation. The solubility of Bi by naturally occurring DOM derived from the soil organic horizon (Oi) and its pH dependence were different from those associated with HA and varied among tree species.

  9. Hazardous gas production by alpha particles in solid organic transuranic waste matrices. 1998 annual progress report

    International Nuclear Information System (INIS)

    LaVerne, J.A.

    1998-01-01

    'This project uses fundamental radiation chemical techniques to elucidate the basic processes occurring in the heavy-ion radiolysis of solid hydrocarbon matrices such as polymers and organic resins that are associated with many of the transuranic waste deposits or the transportation of these radionuclides. The environmental management of mixed waste containing transuranic radionuclides is difficult because these nuclides are alpha particle emitters and the energy deposited by the alpha particles causes chemical transformations in the matrices accompanying the waste. Most radiolysis programs focus on conventional radiation such as gamma rays, but the chemical changes induced by alpha particles and other heavy ions are typically very different and product yields can vary by more than an order of magnitude. The objective of this research is to measure the production of gases, especially molecular hydrogen, produced in the proton, helium ion, and carbon ion radiolysis of selected solid organic matrices in order to obtain fundamental mechanistic information on the radiolytic decomposition of these materials. This knowledge can also be used to directly give reasonable estimates of explosive or flammability hazards in the storage or transport of transuranic wastes in order to enhance the safety of DOE sites. This report summarizes the work after eight months of a three-year project on determining the production of hazardous gases in transuranic waste. The first stage of the project was to design and build an assembly to irradiate solid organic matrices using accelerated ion beams. It is necessary to measure absolute radiolytic yields, and simulate some of the conditions found in the field. A window assembly was constructed allowing the beam to pass consecutively through a collimator, a vacuum exit window and into the solid sample. The beam is stopped in the sample and the entire end of the assembly is a Faraday cup. Integration of the collected current, in conjunction

  10. Fibroblast Cluster Formation on 3D Collagen Matrices Requires Cell Contraction-Dependent Fibronectin Matrix Organization

    Science.gov (United States)

    da Rocha-Azevedo, Bruno; Ho, Chin-Han; Grinnell, Frederick

    2012-01-01

    Fibroblasts incubated on 3D collagen matrices in serum or lysophosphatidic acid (LPA)-containing medium self-organize into clusters through a mechanism that requires cell contraction. However, in platelet-derived growth factor (PDGF)-containing medium, cells migrate as individuals and do not form clusters even though they constantly encounter each other. Here, we present evidence that a required function of cell contraction in clustering is formation of fibronectin fibrillar matrix. We found that in serum or LPA but not in PDGF or basal medium, cells organized FN (both serum and cellular) into a fibrillar, detergent-insoluble matrix. Cell clusters developed concomitant with FN matrix formation. FN fibrils accumulated beneath cells and along the borders of cell clusters in regions of cell-matrix tension. Blocking Rho kinase or myosin II activity prevented FN matrix assembly and cell clustering. Using siRNA silencing and function-blocking antibodies and peptides, we found that cell clustering and FN matrix assembly required α5β1 integrins and fibronectin. Cells were still able to exert contractile force and compact the collagen matrix under the latter conditions, which showed that contraction was not sufficient for cell clustering to occur. Our findings provide new insights into how procontractile (serum/LPA) and promigratory (PDGF) growth factor environments can differentially regulate FN matrix assembly by fibroblasts interacting with collagen matrices and thereby influence mesenchymal cell morphogenetic behavior under physiologic circumstances such as wound repair, morphogenesis and malignancy. PMID:23117111

  11. Fibroblast cluster formation on 3D collagen matrices requires cell contraction dependent fibronectin matrix organization.

    Science.gov (United States)

    da Rocha-Azevedo, Bruno; Ho, Chin-Han; Grinnell, Frederick

    2013-02-15

    Fibroblasts incubated on 3D collagen matrices in serum or lysophosphatidic acid (LPA)-containing medium self-organize into clusters through a mechanism that requires cell contraction. However, in platelet-derived growth factor (PDGF)-containing medium, cells migrate as individuals and do not form clusters even though they constantly encounter each other. Here, we present evidence that a required function of cell contraction in clustering is formation of fibronectin (FN) fibrillar matrix. We found that in serum or LPA but not in PDGF or basal medium, cells organized FN (both serum and cellular) into a fibrillar, detergent-insoluble matrix. Cell clusters developed concomitant with FN matrix formation. FN fibrils accumulated beneath cells and along the borders of cell clusters in regions of cell-matrix tension. Blocking Rho kinase or myosin II activity prevented FN matrix assembly and cell clustering. Using siRNA silencing and function-blocking antibodies and peptides, we found that cell clustering and FN matrix assembly required α5β1 integrins and fibronectin. Cells were still able to exert contractile force and compact the collagen matrix under the latter conditions, which showed that contraction was not sufficient for cell clustering to occur. Our findings provide new insights into how procontractile (serum/LPA) and promigratory (PDGF) growth factor environments can differentially regulate FN matrix assembly by fibroblasts interacting with collagen matrices and thereby influence mesenchymal cell morphogenetic behavior under physiologic circumstances such as wound repair, morphogenesis and malignancy. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The influence of soluble organic matter on shale reservoir characterization

    Directory of Open Access Journals (Sweden)

    Lei Pan

    2016-06-01

    Full Text Available Shale with a maturity within the “oil window” contains a certain amount of residual soluble organic matter (SOM. This SOM have an important influence on characterization of shale reservoir. In this study, two shale samples were collected from the Upper Permian Dalong Formation in the northwestern boundary of Sichuan Basin. Their geochemistry, mineral composition, and pore structure (surface area and pore volume were investigated before and after removing the SOM by means of extraction via dichloromethane or trichloromethane. The results show that the TOC, S1, S2, and IH of the extracted samples decrease significantly, but the mineral composition has no evident change as compared with their raw samples. Thus, we can infer that the original pore structure is thought to be unaffected from the extraction. The SOM occupies pore volume and hinders pores connectivity. The extraction greatly increases the surface area and pore volume of the samples. The residual SOM in the shale samples occur mainly in the micropores and smaller mesopores, and their occupied pore size range seems being constrained by the maturity. For the lower mature shale samples, the SOM is mainly hosted in organic pores that are less than 5 nm in size. For the middle mature shale samples, the micropores and some mesopores ranging between 2 and 20 nm in size are the main storage space for the SOM.

  13. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part I. Theoretical considerations

    International Nuclear Information System (INIS)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-01-01

    Highlights: • Tutorial review addressed to beginners or more experienced analysts. • Theoretical background of effects caused by organic matrices on ICP techniques. • Spatial distribution of carbon species and analytes in plasma. • Carbon spectroscopic and non-spectroscopic interferences in ICP. - Abstract: Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical “matrix removal” approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the

  14. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part I. Theoretical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Leclercq, Amélie, E-mail: amelie.leclercq@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Nonell, Anthony, E-mail: anthony.nonell@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Todolí Torró, José Luis, E-mail: jose.todoli@ua.es [Universidad de Alicante, Departamento de Quimica Analitica, Nutricion y Bromatología, Ap. de Correos, 99, 03080 Alicante (Spain); Bresson, Carole, E-mail: carole.bresson@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vio, Laurent, E-mail: laurent.vio@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vercouter, Thomas, E-mail: thomas.vercouter@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Chartier, Frédéric, E-mail: frederic.chartier@cea.fr [CEA Saclay, DEN, DANS, DPC, 91191 Gif-sur-Yvette (France)

    2015-07-23

    Highlights: • Tutorial review addressed to beginners or more experienced analysts. • Theoretical background of effects caused by organic matrices on ICP techniques. • Spatial distribution of carbon species and analytes in plasma. • Carbon spectroscopic and non-spectroscopic interferences in ICP. - Abstract: Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical “matrix removal” approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the

  15. QSAR models for the removal of organic micropollutants in four different river water matrices

    KAUST Repository

    Sudhakaran, Sairam

    2012-04-01

    Ozonation is an advanced water treatment process used to remove organic micropollutants (OMPs) such as pharmaceuticals and personal care products (PPCPs). In this study, Quantitative Structure Activity Relationship (QSAR) models, for ozonation and advanced oxidation process (AOP), were developed with percent-removal of OMPs by ozonation as the criterion variable. The models focused on PPCPs and pesticides elimination in bench-scale studies done within natural water matrices: Colorado River, Passaic River, Ohio River and Suwannee synthetic water. The OMPs removal for the different water matrices varied depending on the water quality conditions such as pH, DOC, alkalinity. The molecular descriptors used to define the OMPs physico-chemical properties range from one-dimensional (atom counts) to three-dimensional (quantum-chemical). Based on a statistical modeling approach using more than 40 molecular descriptors as predictors, descriptors influencing ozonation/AOP were chosen for inclusion in the QSAR models. The modeling approach was based on multiple linear regression (MLR). Also, a global model based on neural networks was created, compiling OMPs from all the four river water matrices. The chemically relevant molecular descriptors involved in the QSAR models were: energy difference between lowest unoccupied and highest occupied molecular orbital (E LUMO-E HOMO), electron-affinity (EA), number of halogen atoms (#X), number of ring atoms (#ring atoms), weakly polar component of the solvent accessible surface area (WPSA) and oxygen to carbon ratio (O/C). All the QSAR models resulted in a goodness-of-fit, R 2, greater than 0.8. Internal and external validations were performed on the models. © 2011 Elsevier Ltd.

  16. Configuration of organic dye excimers in nanoporous SiO2 matrices

    International Nuclear Information System (INIS)

    Sorokin, A.V.; Gnap, B.A.; Bespalova, I.I.; Yefimova, S.L.; Malyukin, Yu.V.

    2016-01-01

    The effect of cyanine dye 3,3′-dioctadecyloxacarbocyanine perchlorate (DiO) and benzimidazole dye 4-dimethylamino-1,8-naphthoylene-1′,2′-benzimidazole (DNBI) accumulation in nanoporous silica matrices on the dyes luminescence properties has been studied. For both dyes, ground state dimer formation with perpendicular transition dipoles at high dye concentrations has been considered as a result of restricted geometry of the nanoscale pores. The dimer excitation leads to excimer formation revealing by appearance of new long-wavelength luminescence band and shortening the dye luminescence lifetime. In the excimer luminescence excitation spectra two additional bands have been observed, one of which is bathochromically shifted relatively to the absorption band and another one is hypsocromically shifted. Using the Kasha exciton model it was shown that the excimers possess oblique transition dipoles configuration. - Highlights: • Organic dye molecules are efficiently accumulated in nanoporous silica matrices. • Restricted geometry of SiO 2 nanopores provokes excimerization of both cyanine and benzimidazole dyes. • The excimers reveal configuration of oblique dimers. • The excimers are originated from ground state dimers with a perpendicular arrangement of transition dipoles.

  17. Ceramic membrane ozonator for soluble organics removal from produced water

    Science.gov (United States)

    Siagian, U. W. R.; Dwipramana, A. S.; Perwira, S. B.; Khoiruddin; Wenten, I. G.

    2018-01-01

    In this work, the performance of ozonation for degradation of soluble organic compounds in produced water was investigated. Tubular ceramic membrane diffuser (with and without a static mixer in the lumen side) was used to facilitate contact between ozone and produced water. The ozonation was conducted at ozone flow rate of 8 L.min-1, ozone concentration of 0.4 ppm, original pH of the solution, and pressure of 1.2 bar, while the flow rates of the produced water were varied (192, 378 and 830 mL.min-1). It was found that the reduction of benzene, toluene, ethylbenzene, and xylene were 85%, 99%, 85%, and 95%, respectively. A lower liquid flow rate in a laminar state showed a better component reduction due to the longer contacting time between the liquid and the gas phase. The introduction of the static mixer in the lumen side of the membrane as a turbulence promoter provided a positive effect on the performance of the membrane diffuser. The twisted static mixer exhibited the better removal rate than the spiral static mixer.

  18. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part II. Practical considerations

    International Nuclear Information System (INIS)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-01-01

    Graphical abstract: This tutorial review is dedicated to the analysis of organic/hydro-organic matrices by ICP techniques. A state-of-the-art focusing on sample introduction, relevant operating parameters optimization and analytical strategies for elemental quantification is provided. - Highlights: • Practical considerations to perform analyses in organic/hydro-organic matrices. • Description, benefits and drawbacks of recent introduction devices. • Optimization to improve plasma tolerance towards organic/hydro-organic matrices. • Analytical strategies for elemental quantification in organic/hydro-organic matrices. - Abstract: Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review

  19. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: A tutorial review. Part II. Practical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Leclercq, Amélie, E-mail: amelie.leclercq@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Nonell, Anthony, E-mail: anthony.nonell@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Todolí Torró, José Luis, E-mail: jose.todoli@ua.es [Universidad de Alicante, Departamento de Quimica Analitica, Nutricion y Bromatología, Ap. de Correos, 99, 03080 Alicante (Spain); Bresson, Carole, E-mail: carole.bresson@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vio, Laurent, E-mail: laurent.vio@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Vercouter, Thomas, E-mail: thomas.vercouter@cea.fr [CEA Saclay, DEN, DANS, DPC, SEARS, Laboratoire de développement Analytique Nucléaire Isotopique et Elémentaire, 91191 Gif-sur-Yvette (France); Chartier, Frédéric, E-mail: frederic.chartier@cea.fr [CEA Saclay, DEN, DANS, DPC, 91191 Gif-sur-Yvette (France)

    2015-07-23

    Graphical abstract: This tutorial review is dedicated to the analysis of organic/hydro-organic matrices by ICP techniques. A state-of-the-art focusing on sample introduction, relevant operating parameters optimization and analytical strategies for elemental quantification is provided. - Highlights: • Practical considerations to perform analyses in organic/hydro-organic matrices. • Description, benefits and drawbacks of recent introduction devices. • Optimization to improve plasma tolerance towards organic/hydro-organic matrices. • Analytical strategies for elemental quantification in organic/hydro-organic matrices. - Abstract: Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review

  20. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: a tutorial review. Part I. Theoretical considerations.

    Science.gov (United States)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-07-23

    Due to their outstanding analytical performances, inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are widely used for multi-elemental measurements and also for isotopic characterization in the case of ICP-MS. While most studies are carried out in aqueous matrices, applications involving organic/hydro-organic matrices become increasingly widespread. This kind of matrices is introduced in ICP based instruments when classical "matrix removal" approaches such as acid digestion or extraction procedures cannot be implemented. Due to the physico-chemical properties of organic/hydro-organic matrices and their associated effects on instrumentation and analytical performances, their introduction into ICP sources is particularly challenging and has become a full topic. In this framework, numerous theoretical and phenomenological studies of these effects have been performed in the past, mainly by ICP-OES, while recent literature is more focused on applications and associated instrumental developments. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP-OES and ICP-MS. The present Part I, provides theoretical considerations in connection with the physico-chemical properties of organic/hydro-organic matrices, in order to better understand the induced phenomena. This focal point is divided in four chapters highlighting: (i) the impact of organic/hydro-organic matrices from aerosol generation to atomization/excitation/ionization processes; (ii) the production of carbon molecular constituents and their spatial distribution in the plasma with respect to analytes repartition; (iii) the subsequent modifications of plasma fundamental properties; and (iv) the resulting spectroscopic and non spectroscopic interferences. This first part of this tutorial review is addressed either to beginners or to more experienced scientists who are interested in the

  1. Characterisation of volatile organic compounds (VOCs) released by the composting of different waste matrices.

    Science.gov (United States)

    Schiavon, Marco; Martini, Luca Matteo; Corrà, Cesare; Scapinello, Marco; Coller, Graziano; Tosi, Paolo; Ragazzi, Marco

    2017-12-01

    The complaints arising from the problem of odorants released by composting plants may impede the construction of new composting facilities, preclude the proper activity of existing facilities or even lead to their closure, with negative implications for waste management and local economy. Improving the knowledge on VOC emissions from composting processes is of particular importance since different VOCs imply different odour impacts. To this purpose, three different organic matrices were studied in this work: dewatered sewage sludge (M1), digested organic fraction of municipal solid waste (M2) and untreated food waste (M3). The three matrices were aerobically biodegraded in a bench-scale bioreactor simulating composting conditions. A homemade device sampled the process air from each treatment at defined time intervals. The samples were analysed for VOC detection. The information on the concentrations of the detected VOCs was combined with the VOC-specific odour thresholds to estimate the relative weight of each biodegraded matrix in terms of odour impact. When the odour formation was at its maximum, the waste gas from the composting of M3 showed a total odour concentration about 60 and 15,000 times higher than those resulting from the composting of M1 and M2, respectively. Ethyl isovalerate showed the highest contribution to the total odour concentration (>99%). Terpenes (α-pinene, β-pinene, p-cymene and limonene) were abundantly present in M2 and M3, while sulphides (dimethyl sulphide and dimethyl disulphide) were the dominant components of M1. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Analyzing water soluble soil organics as Trifluoroacetyl derivatives by liquid state proton nuclear magnetic resonance

    Science.gov (United States)

    Felipe Garza Sanchez; Zakiya Holmes Leggett; Sabapathy Sankar

    2005-01-01

    In forested ecosystems, water soluble organics play an important role in soil processes including carbon and nutrient turnover, microbial activity and pedogenesis. The quantity and quality (i.e., chemistry) of these materials is sensitive to land management practices. Monitoring alterations in the chemistry of water soluble organics resulting from land management...

  3. Decorin-transforming growth factor- interaction regulates matrix organization and mechanical characteristics of three-dimensional collagen matrices.

    Science.gov (United States)

    Ferdous, Zannatul; Wei, Victoria Mariko; Iozzo, Renato; Höök, Magnus; Grande-Allen, Kathryn Jane

    2007-12-07

    The small leucine-rich proteoglycan decorin has been demonstrated to be a key regulator of collagen fibrillogenesis; decorin deficiencies lead to irregularly shaped collagen fibrils and weakened material behavior in postnatal murine connective tissues. In an in vitro investigation of the contributions of decorin to tissue organization and material behavior, model tissues were engineered by seeding embryonic fibroblasts, harvested from 12.5-13.5 days gestational aged decorin null (Dcn(-/-)) or wild-type mice, within type I collagen gels. The resulting three-dimensional collagen matrices were cultured for 4 weeks under static tension. The collagen matrices seeded with Dcn(-/-) cells exhibited greater contraction, cell density, ultimate tensile strength, and elastic modulus than those seeded with wild-type cells. Ultrastructurally, the matrices seeded with Dcn(-/-) cells contained a greater density of collagen. The decorin-null tissues contained more biglycan than control tissues, suggesting that this related proteoglycan compensated for the absence of decorin. The effect of transforming growth factor-beta (TGF-beta), which is normally sequestered by decorin, was also investigated in this study. The addition of TGF-beta1 to the matrices seeded with wild-type cells improved their contraction and mechanical strength, whereas blocking TGF-beta1 in the Dcn(-/-) cell-seeded matrices significantly reduced the collagen gel contraction. These results indicate that the inhibitory interaction between decorin and TGF-beta1 significantly influenced the matrix organization and material behavior of these in vitro model tissues.

  4. Water soluble organic aerosols in the Colorado Rocky Mountains, USA: composition, sources and optical properties

    OpenAIRE

    Xie, Mingjie; Mladenov, Natalie; Williams, Mark W.; Neff, Jason C.; Wasswa, Joseph; Hannigan, Michael P.

    2016-01-01

    Atmospheric aerosols have been shown to be an important input of organic carbon and nutrients to alpine watersheds and influence biogeochemical processes in these remote settings. For many remote, high elevation watersheds, direct evidence of the sources of water soluble organic aerosols and their chemical and optical characteristics is lacking. Here, we show that the concentration of water soluble organic carbon (WSOC) in the total suspended particulate (TSP) load at a high elevation site in...

  5. Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

    OpenAIRE

    Kristina Wedege; Emil Dražević; Denes Konya; Anders Bentien

    2016-01-01

    Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined ...

  6. On the solubility of nicotinic acid and isonicotinic acid in water and organic solvents

    International Nuclear Information System (INIS)

    Abraham, Michael H.; Acree, William E.

    2013-01-01

    Highlights: ► Solubilities of nicotinic acid and isonicotinic acids in organicsolvents have been determined. ► Solubilities are used to calculate Abraham descriptors for the two acids. ► These descriptors then yield water-solvent and gas-solvent partitions into numerous solvents. ► The solubility of the neutral acids in water is obtained. ► The method is straightforward and can be applied to any set of compound solubilities. -- Abstract: We have determined the solubility of nicotinic acid in four solvents and the solubility of isonicotinic acid in another four solvents. These results, together with literature data on the solubility of nicotinic acid in five other organic solvents and isonicotinic acid in four other organic solvents, have been analyzed through two linear Gibbs energy relationships in order to extract compound properties, or descriptors, that encode various solute–solvent interactions. The descriptors for nicotinic acid and isonicotinic acid can then be used in known equations for partition of solutes between water and organic solvents to predict partition coefficients and then further solubility in a host of organic solvents, as well as to predict a number of other physicochemical properties

  7. The solubilities of significant organic compounds in HLW tank supernate solutions -- FY 1995 progress report

    International Nuclear Information System (INIS)

    Barney, G.S.

    1996-01-01

    At the Hanford Site organic compounds were measured in tank supernate simulant solutions during FY 1995. This solubility information will be used to determine if these organic salts could exist in solid phases (saltcake or sludges) in the waste where they might react violently with the nitrate or nitrite salts present in the tanks. Solubilities of sodium glycolate, succinate, and caproate salts; iron and aluminum and butylphosphate salts; and aluminum oxalate were measured in simulated waste supernate solutions at 25 degree C, 30 degree C, 40 degree C, and 50 degree C. The organic compounds were selected because they are expected to exist in relatively high concentrations in the tanks. The solubilities of sodium glycolate, succinate, caproate, and butylphosphate in HLW tank supernate solutions were high over the temperature and sodium hydroxide concentration ranges expected in the tanks. High solubilities will prevent solid sodium salts of these organic acids from precipitating from tank supernate solutions. The total organic carbon concentrations (YOC) of actual tank supernates are generally much lower than the TOC ranges for simulated supernate solutions saturated (at the solubility limit) with the organic salts. This is so even if all the dissolved carbon in a given tank and supernate is due to only one of these eight soluble compounds (an unlikely situation). Metal ion complexes of and butylphosphate and oxalate in supernate solutions were not stable in the presence of the hydroxide concentrations expected in most tanks. Iron and aluminum dibutylphosphate compounds reacted with hydroxide to form soluble sodium dibutylphosphate and precipitated iron and aluminum hydroxides. Aluminum oxalate complexes were also not stable in the basic simulated supernate solutions. Solubilities of all the organic salts decrease with increasing sodium hydroxide concentration because of the common ion effect of Na+. Increasing temperatures raised the solubilities of the organic

  8. Solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents

    International Nuclear Information System (INIS)

    Fan, Jie-Ping; Yang, Dan; Xu, Xiao-Kang; Guo, Xiao-Jie; Zhang, Xue-Hong

    2015-01-01

    Highlights: • The solubilities of daidzin were measured in various solvents. • The solubility data were correlated by three models. • The thermodynamic properties of the dissolution process were also determined. - Abstract: The solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents was measured by high performance liquid chromatography (HPLC) analysis method from T = (283.2 to 323.2) K at atmosphere pressure. The results show that at higher temperature more daidzin dissolves, and moreover, the solubility increases with the ethyl alcohol mole fraction increase in the (ethyl alcohol + water) mixed solvents. The experimental solubility values were correlated by a simplified thermodynamic equation, λh equation and modified Apelblat equation. Based on the solubility of daidzin, the enthalpy and entropy of solution were also evaluated by van’t Hoff equation. The results illustrated that the dissolution process of daidzin is endothermic and entropy driven

  9. Metal-inorganic-organic matrices as efficient sorbents for hydrogen storage.

    Science.gov (United States)

    Azzouz, Abdelkrim; Nousir, Saadia; Bouazizi, Nabil; Roy, René

    2015-03-01

    Stabilization of metal nanoparticles (MNPs) without re-aggregation is a major challenge. An unprecedented strategy is developed for achieving high dispersion of copper(0) or palladium(0) on montmorillonite-supported diethanolamine or thioglycerol. This results in novel metal-inorganic-organic matrices (MIOM) that readily capture hydrogen at ambient conditions, with easy release under air stream. Hydrogen retention appears to involve mainly physical interactions, slightly stronger on thioglycerol-based MIOM (S-MIOM). Thermal enhancement of desorption suggests also a contribution of chemical interactions. The increase of hydrogen uptake with prolonged contact times arises from diffusion hindrance, which appears to be beneficial by favoring hydrogen entrapment. Even with compact structures, MIOMs act as efficient sorbents with much higher efficiency factor (1.14-1.17 mmol H 2 m(-2)) than many other sophisticated adsorbents reported in the literature. This opens new prospects for hydrogen storage and potential applications in microfluidic hydrogenation reactions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Effect of molecular structure on fragmentation of isolated organic molecules in solid rare gas matrices

    International Nuclear Information System (INIS)

    Kobzarenko, A.V.; Sukhov, F.F.; Orlov, A.Yu.; Kovalev, G.V.; Baranova, I.A.; Feldman, V.I.

    2012-01-01

    The effect of excess energy on the primary radical cations of bifunctional carbonyl compounds and aliphatic alkynes was simulated by matrix isolation method using rare gas matrices with various ionization potentials. The formation of fragmentation products was monitored by EPR and FTIR spectroscopy. It was shown that the radical cations of bifunctional compounds (CH 3 OCH 2 COCH 3 and CH 3 COCOCH 3 ) dissociated effectively yielding · CH 3 radicals upon irradiation in solid argon matrix at T≤16 K. In addition to isolated methyl radicals, the radical pairs consisting of two methyl radicals separated by two CO molecules were detected in the case of diacetyl. The probability of fragmentation decreases with the decreasing excess energy by switching from Ar to Xe. In general, bifunctional molecules were found to be less stable to “hot” ionic fragmentation in low-temperature solids in comparison with simple prototype compounds. In the case of alkynes of the R--C≡CH type, a noticeable yield of fragmentation products was observed when R=–C(CH 3 ) 3 , but it was negligible for R=–CH 3 . The mechanisms of “hot” reactions and excess energy relaxation are discussed. - Highlights: ► Radiolysis of bifunctional organic compounds and alkynes. ► Dependence of “hot” fragmentation probability from molecular structure. ► Ions of bifunctional compounds are less stable than those of monofunctional ones. ► Alkynes are rather stable to “hot” fragmentation.

  11. Effect of molecular structure on fragmentation of isolated organic molecules in solid rare gas matrices

    International Nuclear Information System (INIS)

    Kobrazenko, A.V.; Sukhov, F.F.; Orlov, A.Yu.; Kovalev, G.V.; Baranova, I.A.; Feldman, V.I.

    2011-01-01

    Complete text of publication follows. Elucidation of high-energy reaction pathways in the condensed phase is an important issue for basic understanding of the radiation stability of complex organic molecules. As was shown previously, organic radical cations (RC) may undergo fragmentation or rearrangement in solid matrices due to excess energy. The probability of this process depends on both ionization potential (IP) of the molecule and molecular structure. In the present work we have studied the role of 'hot' ionic reaction channels for RC of some bifunctional compounds and alkynes. The effect of excess energy was simulated by matrix isolation method as described in detail earlier. The formation of fragmentation products was monitored by EPR and FTIR spectroscopy. In the present work it was shown that the RC of bifunctional compounds (CH 3 OCH 2 COCH 3 , CH 3 CO(CH 2 ) n COCH 3 , n 0/2) dissociated efficiently producing · CH 3 radicals upon irradiation in solid argon matrix at T ≤ 16 K. The probability of fragmentation decreases with decrease of excess energy by switching from Ar to Xe. It is worth noting that acetone RC does not show fragmentation under these conditions. Thus, bifunctional molecules were found to be less stable to 'hot' ionic fragmentation in low-temperature solids in comparison with simple prototype carbonyl compounds. In the case of alkynes of the R-C ≡ CH type, a noticeable yield of fragmentation products was observed when R = -C(CH 3 ) 3 , but it was negligible for R = -CH 3 . It means that the presence of triple bond stabilizes the molecular skeleton of linear alkynes toward 'hot' fragmentation, similarly as it was shown for alkenes. The mechanisms of 'hot' reactions and excess energy relaxation are discussed. This work was supported by the Russian Foundation for Basic Research (project 09-03-00848a).

  12. Diffusion and solubility coefficients determined by permeation and immersion experiments for organic solvents in HDPE geomembrane.

    Science.gov (United States)

    Chao, Keh-Ping; Wang, Ping; Wang, Ya-Ting

    2007-04-02

    The chemical resistance of eight organic solvents in high density polyethylene (HDPE) geomembrane has been investigated using the ASTM F739 permeation method and the immersion test at different temperatures. The diffusion of the experimental organic solvents in HDPE geomembrane was non-Fickian kinetic, and the solubility coefficients can be consistent with the solubility parameter theory. The diffusion coefficients and solubility coefficients determined by the ASTM F739 method were significantly correlated to the immersion tests (pHDPE as barriers in the field.

  13. Evaluation of soluble organic compounds generated by radiological degradation of asphalt

    International Nuclear Information System (INIS)

    Fukumoto, M.; Nishikawa, Y.; Kagawa, A.; Kawamura, K.

    2000-12-01

    The soluble organic compounds generated by radiological degradation of asphalt (γ ray) were confirmed as a part of influence of the bituminized waste degradation in the TRU waste repository. Especially, the influence of the nitrate was focused on. As a result, the concentration of the soluble organic compounds generated by radiological degradation of asphalt (10 MGy, γ ray which is correspond to absorbed dose of asphalt for 1,000,000 years) were lower (each formic acid: about 50 mg/dm 3 , acetic acid: about 30 mg/dm 3 and oxalic acid: about 2 mg/dm 3 ) than that of the formic acid, the acetic acid and the oxalic acid which Valcke et al. had shown (the influence of the organic at the solubility examination which uses Pu and Am). Moreover, the change in the concentration of TOC and the soluble organic compounds (formic acid, acetic acid and oxalic acid) is little under the existence of nitrate ion. That is, the formic acid and acetic acid which can be organic ligands were generated little by oxidative decomposition of asphalt in the process that nitrate ion becomes nitride ion by radiation. The influence of the soluble organic compounds by the radiological degradation of the asphalt (γ ray) on adsorption and solubility by the complexation of radionuclides in the performance assessment can be limited. (author)

  14. An estimation of influence of humic acid and organic matter originated from bentonite on samarium solubility

    International Nuclear Information System (INIS)

    Kanaji, Mariko; Sato, Haruo; Sasahira, Akira

    1999-10-01

    Organic acids in groundwater are considered to form complexes and increase the solubility of radionuclides released from vitrified waste in a high-level radioactive waste (HLW) repository. To investigate whether the solubility of samarium (Sm) is influenced by organic substances, we measured Sm solubility in the presence of different organic substances and compared those values with results from thermodynamic predictions. Humic acid (Aldrich) is commercially available and soluble organic matter originated from bentonite were used as organic substances in this study. Consequently, the solubility of Sm showed a tendency to apparently increase with increasing the concentration of humic acid, but in the presence of carbonate, thermodynamic predictions suggested that the dominant species are carbonate complexes and that the effect of organic substances are less than that of carbonate. Based on total organic carbon (TOC), the increase of Sm solubility measured with humic acid (Aldrich) was more significant than that in the case with soluble organic matter originated from bentonite. Since bentonite is presumed to include also simple organic matters of which stability constant for forming complexes is low, the effect of soluble organic matter originated from bentonite on the solubility of Sm is considered to be less effective than that of humic acid (Aldrich). Experimental values were compared with model prediction, proposed by Kim, based on data measured in a low pH region. Tentatively we calculated the increase in Sm solubility assuming complexation with humic acid. Trial calculations were carried out on the premise that the complexation reaction of metal ion with humic acid is based on neutralization process by 1-1 complexation. In this process, it was assumed that one metal ion coordinates with one unit of complexation sites which number of proton exchange sites is equal to ionic charge. Consequently, Kim's model indicated that carbonate complexes should be dominant

  15. Introduction of organic/hydro-organic matrices in inductively coupled plasma optical emission spectrometry and mass spectrometry: a tutorial review. Part II. Practical considerations.

    Science.gov (United States)

    Leclercq, Amélie; Nonell, Anthony; Todolí Torró, José Luis; Bresson, Carole; Vio, Laurent; Vercouter, Thomas; Chartier, Frédéric

    2015-07-23

    Inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are increasingly used to carry out analyses in organic/hydro-organic matrices. The introduction of such matrices into ICP sources is particularly challenging and can be the cause of numerous drawbacks. This tutorial review, divided in two parts, explores the rich literature related to the introduction of organic/hydro-organic matrices in ICP sources. Part I provided theoretical considerations associated with the physico-chemical properties of such matrices, in an attempt to understand the induced phenomena. Part II of this tutorial review is dedicated to more practical considerations on instrumentation, instrumental and operating parameters, as well as analytical strategies for elemental quantification in such matrices. Two important issues are addressed in this part: the first concerns the instrumentation and optimization of instrumental and operating parameters, pointing out (i) the description, benefits and drawbacks of different kinds of nebulization and desolvation devices and the impact of more specific instrumental parameters such as the injector characteristics and the material used for the cone; and, (ii) the optimization of operating parameters, for both ICP-OES and ICP-MS. Even if it is at the margin of this tutorial review, Electrothermal Vaporization and Laser Ablation will also be shortly described. The second issue is devoted to the analytical strategies for elemental quantification in such matrices, with particular insight into the isotope dilution technique, particularly used in speciation analysis by ICP-coupled separation techniques. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Microscale Solubility Measurements of Matrix-Assisted Laser Desorption-Ionization (MALDI) Matrices Using Attenuated Total Reflection (ATR) Fourier Transform Infrared Spectroscopy (FT-IR) Coupled with Partial Least Squares (PLS) Analysis.

    Science.gov (United States)

    Gorre, Elsa; Owens, Kevin G

    2016-11-01

    In this work an attenuated total reflection Fourier transform infrared (FT-IR) absorption based method is used to measure the solubility of two matrix-assisted laser desorption-ionization (MALDI) matrices in a few pure solvents and mixtures of acetonitrile and water using low microliter amounts of solution. Results from a method that averages the values obtained from multiple calibration curves created by manual peak picking are compared to those predicted using a partial least squares (PLS) chemometrics approach. The PLS method provided solubility values that were in good agreement with the manual method with significantly greater ease of analysis. As a test, the solubility of adipic acid in acetone was measured using the two methods of analysis, and the values are in good agreement with solubility values reported in literature. The solubilities of the MALDI matrices α-cyano-4-hydroxy cinnamic acid (CHCA) and sinapinic acid (SA) were measured in a series of mixtures made from acetonitrile (ACN) and water; surprisingly, the results show a highly nonlinear trend. While both CHCA and SA show solubility values of less than 10 mg/mL in the pure solvents, the solubility value for SA increases to 56.3 mg/mL in a 75:25 v/v ACN:water mixture. This can have a significant effect on the matrix-to-analyte ratios in the MALDI experiment when sample protocols call for preparation of a saturated solution of the matrix in the chosen solvent system. © The Author(s) 2016.

  17. New sample treatment strategies for the determination of organic contaminants in environmental matrices.

    OpenAIRE

    Casas Ferreira, Ana María

    2011-01-01

    [ES] El objeto general de esta memoria consiste en proponer y desarrollar nuevas estrategias de tratamiento de muestra para la determinación de contaminantes orgánicos en matrices medioambientales. En muchos casos, cuando se trabaja con diferentes matrices, tales como aguas o suelos, es necesaria la utilización de técnicas de pretratamiento de muestra previas al análisis instrumental, cuyo objetivo principal es aislar los analitos de interés del resto de componentes presentes en la matriz...

  18. Measurement and correlation of solubility of ciclesonide in seven pure organic solvents

    International Nuclear Information System (INIS)

    Zhou, Lina; Yin, Qiuxiang; Guo, Zhiqiang; Lu, Haijiao; Liu, Mingyan; Chen, Wei; Hou, Baohong

    2017-01-01

    Highlights: • The solubility of ciclesonide in seven pure organic solvents was determined by gravimetric method. • The solubility order was interpreted by virtue of density function theory (DFT). • The experimental solubility of ciclesonide was correlated by four thermodynamic models. • Mixing thermodynamic properties of ciclesonide were calculated and discussed. - Abstract: The solubility of ciclesonide in seven organic solvents (ethanol, 2-propanol, 1-propanol, 1-butanol, acetonitrile, toluene and ethyl acetate) in the temperature range from 278.15 K to 313.15 K was measured by gravimetrical method under atmospheric pressure. The results indicate that the solubility of ciclesonide increases with elevating temperature in all investigated solvents. The solubility order in different solvents was interpreted through comparing interaction force between solute and solvent molecules by virtue of density function theory (DFT). Thermodynamic equations including the modified Apelblat equation, λh equation, Wilson equation and NRTL equation are all suitable to correlate the solubility results. Based on the Wilson equation, the thermodynamic parameters from the mixing process are calculated, and the results indicate the mixing process of ciclesonide in the selected pure solvents is spontaneous and entropy-driven.

  19. Study of N-cinnamoylphenylhydroxylaminate solubility in water and organic solvents

    International Nuclear Information System (INIS)

    Pilipenko, A.T.; Shpak, Eh.A.; Samchuk, A.I.

    1975-01-01

    The composition of complexes of N-cinnamoylphenylhydroxylamine with copper, cadmium, lead, indium, iron, gallium, titanium, zirconium, hafnium, niobium, tantalum, tungsten, molybdenum and vanadium was determined. The solubility products of the N-cinnamoylphenylhydroxylaminates of copper, cadmium, indium, gallium and iron were determined by the method of measuring the solubility of precipitates in acid. The solubility of N-cinnamoylphenylhydroxalaminates of cadmium, indium, iron, titanium, zirconium, hafnium, niobium, tantalum, vanadium, molybdenum and tungsten in organic solvents was studied. Two-phase constants for the stability of the complexes were calculated. (author)

  20. Inkjet Printing of Organic Light-Emitting Diodes Based on Alcohol-Soluble Polyfluorenes

    Science.gov (United States)

    Odod, A. V.; Gadirov, R. M.; Solodova, T. A.; Kurtsevich, A. E.; Il'gach, D. M.; Yakimanskii, A. V.; Burtman, V.; Kopylova, T. N.

    2018-04-01

    Ink compositions for inkjet printing based on poly(9.9-dioctylfluorene) and its alcohol-soluble analog are created. Current-voltage, brightness-voltage, and spectral characteristics are compared for one- and twolayer polymer structures of organic light-emitting diodes. It is shown that the efficiency of the alcohol-soluble polyfluorene analog is higher compared to poly(9.9-dioctylfluorene), and the possibility of viscosity optimization is higher compared to aromatic chlorinated solvents.

  1. Binary systems solubilities of inorganic and organic compounds, v.1 pt.2

    CERN Document Server

    Stephen, H

    2013-01-01

    Solubilities of Inorganic and Organic Compounds, Volume 1: Binary Systems, Part 1 is part of an approximately 5,500-page manual containing a selection from the International Chemical Literature on the Solubilities of Elements, Inorganic Compounds, Metallo-organic and Organic Compounds in Binary, Ternary and Multi-component Systems. A careful survey of the literature in all languages by a panel of scientists specially appointed for the task by the U.S.S.R. Academy of Sciences, Moscow, has made the compilation of this work possible. The complete English edition in five separately bound volumes w

  2. Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

    NARCIS (Netherlands)

    Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

    2013-01-01

    Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

  3. Effect of atmospheric organic complexation on iron-bearing dust solubility

    Directory of Open Access Journals (Sweden)

    R. Paris

    2013-05-01

    Full Text Available Recent studies reported that the effect of organic complexation may be a potentially important process to be considered by models estimating atmospheric iron flux to the ocean. In this study, we investigated this process effect by a series of dissolution experiments on iron-bearing dust in the presence or the absence of various organic compounds (acetate, formate, oxalate, malonate, succinate, glutarate, glycolate, lactate, tartrate and humic acid as an analogue of humic like substances, HULIS typically found in atmospheric waters. Only 4 of tested organic ligands (oxalate, malonate, tartrate and humic acid caused an enhancement of iron solubility which was associated with an increase of dissolved Fe(II concentrations. For all of these organic ligands, a positive linear dependence of iron solubility to organic concentrations was observed and showed that the extent of organic complexation on iron solubility decreased in the following order: oxalate >malonate = tartrate > humic acid. This was attributed to the ability of electron donors of organic ligands and implies a reductive ligand-promoted dissolution. This study confirms that among the known atmospheric organic binding ligands of Fe, oxalate is the most effective ligand promoting dust iron solubility and showed, for the first time, the potential effect of HULIS on iron dissolution under atmospheric conditions.

  4. Protein/ionic liquid/glassy carbon sensors following analyte focusing by ionic liquid micelle collapse for simultaneous determination of water soluble vitamins in plasma matrices.

    Science.gov (United States)

    Abd El-Hady, D; Albishri, H M

    2015-07-01

    Two novel sensors based on human serum albumin (HSA)-ionic liquid (IL) and bovine serum albumin (BSA)-ionic liquid (IL) composites modified glassy carbon electrode (GCE) were produced for simultaneous determination of water soluble vitamins B2, B6 and C in human plasma following analytes focusing by IL micelles collapse (AFILMC). For selective and efficient extraction, vitamins were dissolved in 3.0molL(-1) micellar solution of 1-octyl-3-methyl imidazolium bromide IL. The extracted vitamins were hydrodynamically injected by 25mbar for 20s into a running buffer of 12.5mmolL(-1) phosphate at pH 6.0 followed by electrochemical detection (ECD) on protein/1-octyl-3-methyl imidazolium hexafluorophosphate IL/GC sensors. The chemical stability of proposed sensors was achieved up to 7 days without any decomposition of PF6-based IL/protein and adsorption of interfering ions. In the current work, the sensitivity enhancement factor (SEF) up to 5000-fold was achieved using the AFILMC/ECD setup compared to conventional CE/UV. Under optimal conditions, linear calibration graphs were obtained from 0.5, 0.5 and 1.0 to 1500.0µgmL(-1) of vitamins B2, B6 and C, respectively. Detection limits of analytes were ranged from 180.0 to 520.0ngmL(-1). The proposed AFILMC/ECD setup was successfully applied to the assay of trace level quantification of vitamins in human plasma samples and also their binding constants with HSA and BSA were determined. The concurrent use of IL micelles for the proposed separation and detection processes exhibited some advantages, such as, a reduction of use toxic solvents, an efficient extraction and a direct injection of samples with a short-single run. Furthermore, IL micelles, having variable possibility of interactions, facilitated the successful achievements of AFILMC/ECD setup for the quantification of vitamins in plasma matrices. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. QuEChERS sample preparation for the determination of pesticides and other organic residues in environmental matrices: a critical review.

    Science.gov (United States)

    Bruzzoniti, Maria Concetta; Checchini, Leonardo; De Carlo, Rosa Maria; Orlandini, Serena; Rivoira, Luca; Del Bubba, Massimo

    2014-07-01

    Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) is an extraction and clean-up technique originally developed for recovering pesticide residues from fruits and vegetables. Since its introduction, and until December 2013, about 700 papers have been published using the QuEChERS technique, according to a literature overview carried out using SciFinder, Elsevier SciVerse, and Google search engines. Most of these papers were dedicated to pesticide multiresidue analysis in food matrices, and this topic has been thoroughly reviewed over recent years. The QuEChERS approach is now rapidly developing beyond its original field of application to analytes other than pesticides, and matrices other than food, such as biological fluids and non-edible plants, including Chinese medicinal plants. Recently, the QuEChERS concept has spread to environmental applications by analyzing not only pesticides but also other compounds of environmental concern in soil, sediments, and water. To the best of our knowledge, QuEChERS environmental applications have not been reviewed so far; therefore, in this contribution, after a general discussion on the evolution and changes of the original QuEChERS method, a critical survey of the literature regarding environmental applications of conventional and modified QuEChERS methodology is provided. The overall recoveries obtained with QuEChERS and other extraction approaches (e.g., accelerated solvent extraction, ultrasonic solvent extraction, liquid/solid extraction, and soxhlet extraction) were compared, providing evidence for QuEChERS higher recoveries for various classes of compounds, such as biopesticides, chloroalkanes, phenols, and perfluoroalkyl substances. The role of physicochemical properties of soil (i.e., clay and organic carbon content, as well as cation exchange capacity) and target analytes (i.e., log KOW, water solubility, and vapor pressure) were also evaluated in order to interpret recovery and matrix effect data.

  6. Solubility studies of inorganic–organic hybrid nanoparticle photoresists with different surface functional groups

    KAUST Repository

    Li, Li

    2016-01-01

    © 2016 The Royal Society of Chemistry. The solubility behavior of Hf and Zr based hybrid nanoparticles with different surface ligands in different concentrations of photoacid generator as potential EUV photoresists was investigated in detail. The nanoparticles regardless of core or ligand chemistry have a hydrodynamic diameter of 2-3 nm and a very narrow size distribution in organic solvents. The Hansen solubility parameters for nanoparticles functionalized with IBA and 2MBA have the highest contribution from the dispersion interaction than those with tDMA and MAA, which show more polar character. The nanoparticles functionalized with unsaturated surface ligands showed more apparent solubility changes after exposure to DUV than those with saturated ones. The solubility differences after exposure are more pronounced for films containing a higher amount of photoacid generator. The work reported here provides material selection criteria and processing strategies for the design of high performance EUV photoresists.

  7. Solubility studies of inorganic–organic hybrid nanoparticle photoresists with different surface functional groups

    KAUST Repository

    Li, Li; Chakrabarty, Souvik; Jiang, Jing; Zhang, Ben; Ober, Christopher; Giannelis, Emmanuel P.

    2016-01-01

    . The nanoparticles regardless of core or ligand chemistry have a hydrodynamic diameter of 2-3 nm and a very narrow size distribution in organic solvents. The Hansen solubility parameters for nanoparticles functionalized with IBA and 2MBA have the highest contribution

  8. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

    Energy Technology Data Exchange (ETDEWEB)

    Sortino, Orazio [Dipartimento di Scienze Agronomiche Agrochimiche e delle Produzioni Animali, Universita degli Studi di Catania, Via Valdisavoia 5, 95123 Catania (Italy); Dipasquale, Mauro [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Montoneri, Enzo, E-mail: enzo.montoneri@unito.it [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Tomasso, Lorenzo; Perrone, Daniele G. [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe [Dipartimento di Valorizzazione e Protezione delle Risorse Agroforestali, Universita di Torino, Via L. da Vinci 44, 10095 Grugliasco (Italy)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Municipal bio-wastes are a sustainable source of bio-based products. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics promote chlorophyll synthesis. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. Black-Right-Pointing-Pointer Sustainable chemistry exploiting urban refuse allows sustainable development. Black-Right-Pointing-Pointer Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.

  9. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

    International Nuclear Information System (INIS)

    Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo; Tomasso, Lorenzo; Perrone, Daniele G.; Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe

    2012-01-01

    Highlights: ► Municipal bio-wastes are a sustainable source of bio-based products. ► Refuse derived soluble bio-organics promote chlorophyll synthesis. ► Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. ► Sustainable chemistry exploiting urban refuse allows sustainable development. ► Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.

  10. Complexation with dissolved organic matter and solubility control of heavy metals in sandy soil

    NARCIS (Netherlands)

    Weng, L.; Temminghoff, E.J.M.; Lofts, S.; Tipping, E.; Riemsdijk, van W.H.

    2002-01-01

    The complexation of heavy metals with dissolved organic matter (DOM) in the environment influences the solubility and mobility of these metals. In this paper, we measured the complexation of Cu, Cd, Zn, Ni, and Pb with DOM in the soil solution at pH 3.7-6.1 using a Donnan membrane technique. The

  11. SOLUBILITY OF ORGANIC BIOCIDES IN SUPERCRITICAL CO2 AND CO2+ COSOLVENT MIXTURES

    Science.gov (United States)

    Solubilities of four organic biocides in supercritical carbon dioxide (Sc-CO2) were measured using a dynamic flowr apparatus over a pressure range of 10 to 30 MPa and temperature of 35-80 degrees C. The biocides studied were: Amical-48 (diiodomethyl p-tolyl sulfone), chlorothalo...

  12. The solubilities of significant organic compounds in HLW tank supernate solutions

    International Nuclear Information System (INIS)

    Barney, G.S.

    1994-08-01

    Large quantities of organic chemicals used in reprocessing spent nuclear-fuels at the Hanford Site have accumulated in underground high-level radioactive waste tanks. The organic content of these tanks must he known so that the potential for hazardous reactions between organic components and sodium nitrate/nitrite salts in the waste can he evaluated. The solubilities of organic compounds described in this report will help determine if they are present in the solid phases (salt cake and sludges) as well as the liquid phase (interstitial liquor/supernate) in the tanks. The solubilities of five significant sodium salts of carboxylic acids and aminocarboxylic acids [sodium oxalate, formate, citrate, nitrilotriacetate (NTA) and ethylendiaminetetraacetate (EDTA)] were measured in a simulated supernate solution at 25 degrees C, 30 degrees C, 40 degrees C, and 50 degrees C

  13. Influence of organic matter on the solubility of ThO2 and geochemical modeling

    International Nuclear Information System (INIS)

    Liu Dejun; Luo Tian; Maes, N.; Bruggeman, C.

    2014-01-01

    Thorium (IV) is widely considered in laboratory experiments as a suitable chemical analogue for long-lived tetravalent actinides. Th (IV) is redox-insensitive, as an analogue for U (IV) to study the influence of natural organic matter on the solubility. The solubility of crystalline ThO 2 (cr) has been measured under geochemical conditions representative for the Boom Clay using Real Boom Clay Water containing organic matter to assess its influence on the ThO 2 (cr) solubility. For the purpose of comparison, Aldrich Humic Acid was also investigated. Solubility measurements of ThO 2 (cr) were approached from under-saturation in an anaerobic glove box with a controlled Ar0.4%CO 2 atmosphere. Th concentration is determined after 30000 MWCO, 300000 MWCO, and 0.45 μm filtration to distinguish solid (0.45 μm), larger colloids (300000 MWCO), and small dissolved species(30000 MWCO). X-ray diffraction was carried out to investigate the transformation of ThO 2 (cr) phase during the contact with Boom Clay Water. In Synthetic Boom Clay Water (without organic matter) the concentrations of Th (IV) are 5 × l0 -ll mol/L, 4 × lO -10 mol/L, and 8 × lO -8 mol/L after 30000 MWCO, 300000 MWCO, and 0. 45 μm filtration, respectively. It indicated the existence of inorganic colloids in solution. The increase of the total Th solution concentration with increasing organic matter concentration revealed a complexation-like interaction between Th and organic matter. All the experimental data could be modeled by Tipping humic ion-binding model VI using a combination of solubility calculations and complexation reactions between Th (IV) and organic matter functional groups. Similar to the investigation of Eu 3+ solubility, the affinity of organic matter for Th was higher for Aldrich humic acid compared to Boom Clay organic matter. However, Boom Clay organic matter with different size had the similar complexation affinity with Th (IV). (authors)

  14. Porous Aluminum Oxide and Magnesium Oxide Films Using Organic Hydrogels as Structure Matrices

    Directory of Open Access Journals (Sweden)

    Zimei Chen

    2018-03-01

    Full Text Available We describe the synthesis of mesoporous Al2O3 and MgO layers on silicon wafer substrates by using poly(dimethylacrylamide hydrogels as porogenic matrices. Hydrogel films are prepared by spreading the polymer through spin-coating, followed by photo-cross-linking and anchoring to the substrate surface. The metal oxides are obtained by swelling the hydrogels in the respective metal nitrate solutions and subsequent thermal conversion. Combustion of the hydrogel results in mesoporous metal oxide layers with thicknesses in the μm range and high specific surface areas up to 558 m2∙g−1. Materials are characterized by SEM, FIB ablation, EDX, and Kr physisorption porosimetry.

  15. Environmentally friendly synthesis of organic-soluble silver nanoparticles for printed electronics

    International Nuclear Information System (INIS)

    Lee, Kwi Jong; Jun, Byung Ho; Choi, Junrak; Lee, Young Il; Joung, Jaewoo; Oh, Yong Soo

    2007-01-01

    In this study, we attempted to synthesize organic-soluble silver nanoparticles in the concentrated organic phase with an environmentally friendly method. The fully organic phase system contains silver acetate as a silver precursor, oleic acid as both a medium and a capping molecule, and tin acetate as a reducing agent. Monodisperse silver nanoparticles with average diameters of ca. 5 nm can be easily synthesized at large scale. Only a small usage of tin acetate ( 90%). Also, it was investigated that the residual tin atom does not exist in the synthesized silver nanoparticles. This implied that tin acetate acts as a reducing catalyst

  16. Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

    Science.gov (United States)

    Wedege, Kristina; Dražević, Emil; Konya, Denes; Bentien, Anders

    2016-01-01

    Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined with single cell battery RFB tests on selected redox pairs. Data shows that both the solubility and redox potential are determined by the position of the side groups and only to a small extent by the number of side groups. Additionally, the chemical stability and possible degradation mechanisms leading to capacity loss over time are discussed. The main challenge for the development of all-organic RFBs is to identify a redox pair for the positive side with sufficiently high stability and redox potential that enables battery cell potentials above 1 V. PMID:27966605

  17. Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

    Science.gov (United States)

    Wedege, Kristina; Dražević, Emil; Konya, Denes; Bentien, Anders

    2016-12-01

    Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined with single cell battery RFB tests on selected redox pairs. Data shows that both the solubility and redox potential are determined by the position of the side groups and only to a small extent by the number of side groups. Additionally, the chemical stability and possible degradation mechanisms leading to capacity loss over time are discussed. The main challenge for the development of all-organic RFBs is to identify a redox pair for the positive side with sufficiently high stability and redox potential that enables battery cell potentials above 1 V.

  18. Temperature dependence of electron spin-lattice relaxation of radiation-produced silver atoms in polycrystalline aqueous and glassy organic matrices. Importance of relaxation by tunneling modes in disordered matrices

    International Nuclear Information System (INIS)

    Michalik, J.; Kevan, L.

    1978-01-01

    The electron spin-lattice relaxation of trapped silver atoms in polycrystalline ice matrices and in methanol, ethanol, propylene carbonate, and 2-methyltetrahydrofuran organic glasses has been directly studied as a function of temperature by the saturation-recovery method. Below 40 K the dominant electron spin-lattice relaxation mechanism involves modulation of the electron nuclear dipolar interaction with nuclei in the radical's environment by tunneling of those nuclei between two nearly equal energy configurations. This relaxation mechanism occurs with high efficiency, has a characteristic linear temperature dependence, and is typically found in highly disordered matrices. The efficiency of this relaxation mechanism seems to decrease with decreasing polarity of the matrix. Deuteration experiments show that the tunneling nuclei are protons and in methanol it is shown that the methyl protons have more tunneling modes available than the hydroxyl protons. In polycrystalline ice matrices silver atoms can be stabilized with two different orientations of surrounding water molecules; the efficiency of the tunneling relaxation reflects this difference. From these and previous results on tunneling relaxation of trapped electrons in glassy matrices it appears that tunneling relaxation may be used to distinguish models with different geometrical configurations and to determine the relative rigidity of such configurations around trapped radicals in disordered solids. (author)

  19. Effects of organic matters coming from Chinese tea on soluble copper release from copper teapot

    International Nuclear Information System (INIS)

    Ni Lixiao; Li Shiyin

    2008-01-01

    The morphology and elemental composition of the corrosion products of copper teapot's inner-surface were characterized by the scanning electron microscopy and energy dispersive X-ray surface analysis (SEM/EDS), X-ray powder diffraction (XRD) and X-ray photon spectroscopy (XPS) analysis. It was revealed that Cu, Fe, Ca, P, Si and Al were the main elements of corrosion by-products, and the α-SiO 2 , Cu 2 O and CaCO 3 as the main mineral components on the inner-surface of copper teapot. The effects of organic matters coming from Chinese tea on soluble copper release from copper teapots in tap water were also investigated. The results showed that the doses of organic matter (as TOC), temperate and stagnation time have significant effects on the concentration of soluble copper released from copper teapots in tap water

  20. Water uptake by fresh Indonesian peat burning particles is limited by water-soluble organic matter

    Science.gov (United States)

    Chen, Jing; Hapsari Budisulistiorini, Sri; Itoh, Masayuki; Lee, Wen-Chien; Miyakawa, Takuma; Komazaki, Yuichi; Qing Yang, Liu Dong; Kuwata, Mikinori

    2017-09-01

    The relationship between hygroscopic properties and chemical characteristics of Indonesian biomass burning (BB) particles, which are dominantly generated from peatland fires, was investigated using a humidified tandem differential mobility analyzer. In addition to peat, acacia (a popular species at plantation) and fern (a pioneering species after disturbance by fire) were used for experiments. Fresh Indonesian peat burning particles are almost non-hygroscopic (mean hygroscopicity parameter, κ octanol-water partitioning method. κ values for the water extracts are high, especially for peat burning particles (A0 (a whole part of the water-soluble fraction): κ = 0.18, A1 (highly water-soluble fraction): κ = 0.30). This result stresses the importance of both the WSOC fraction and κ of the water-soluble fraction in determining the hygroscopicity of organic aerosol particles. Values of κ correlate positively (R = 0.89) with the fraction of m/z 44 ion signal quantified using a mass spectrometric technique, demonstrating the importance of highly oxygenated organic compounds to the water uptake by Indonesian BB particles. These results provide an experimentally validated reference for hygroscopicity of organics-dominated particles, thus contributing to more accurate estimation of environmental and climatic impacts driven by Indonesian BB particles on both regional and global scales.

  1. Solubility and solution thermodynamics of 2-methyl-6-nitroaniline in ten organic solvents at elevated temperatures

    International Nuclear Information System (INIS)

    Cong, Yang; Wang, Jian; Du, Cunbin; Han, Shuo; Zhao, Hongkun

    2016-01-01

    Highlights: • Solubility of 2-methyl-6-nitroaniline in ten solvents were determined. • The solubility were correlated with four thermodynamic models. • Standard dissolution enthalpy and excess enthalpy of the solutions were computed. - Abstract: Knowledge of solubility for 2-methyl-6-nitroaniline in different solvents is essential for its purification and further theoretical studies. In this paper, the solid-liquid equilibrium for 2-methyl-6-nitroaniline in ten pure organic solvents (methanol, ethanol, n-propanol, isopropanol, toluene, ethyl acetate, acetonitrile, acetone, cyclohexane and 1,4-dioxane) was established using the isothermal saturation method at temperatures T = (278.15–313.15) K under pressure of 101.2 kPa, and the solubility of 2-methyl-6-nitroaniline in these solvents were determined by a high-performance liquid chromatography (HPLC). In general, the mole fraction solubility followed the following order from high to low in different solvents: 1,4-dioxane (0.1799–0.3390) > acetone (0.1128–0.3010) > ethyl acetate (0.08414–0.2654) > acetonitrile (0.04179–0.2027) > toluene (0.02367–0.1104) > n-propanol (0.01080–0.04514) > ethanol (0.01020–0.04202) > isopropanol (0.008595–0.03763) > methanol (0.007391–0.03198) > cyclohexane (0.001027–0.005617). The modified Apelblat equation, λh equation, Wilson model and NRTL model were employed to correlate the measured solubility data of 2-methyl-6-nitroaniline in the selected solvents. Results indicated that the largest values of RAD and RMSD acquired by the four models were less than 0.76% and 9.13 × 10"−"4, respectively. The modified Apelblat equation provided better results than the other three models. Furthermore, the standard dissolution enthalpy and excess enthalpy of the solutions were computed from the solubility values. The standard dissolution enthalpies vary within the range from (14.88 to 45.57) kJ·mol"−"1 and are all positive, the dissolution process of 2-methyl-6

  2. Water uptake by fresh Indonesian peat burning particles is limited by water-soluble organic matter

    Directory of Open Access Journals (Sweden)

    J. Chen

    2017-09-01

    Full Text Available The relationship between hygroscopic properties and chemical characteristics of Indonesian biomass burning (BB particles, which are dominantly generated from peatland fires, was investigated using a humidified tandem differential mobility analyzer. In addition to peat, acacia (a popular species at plantation and fern (a pioneering species after disturbance by fire were used for experiments. Fresh Indonesian peat burning particles are almost non-hygroscopic (mean hygroscopicity parameter, κ < 0.06 due to predominant contribution of water-insoluble organics. The range of κ spans from 0.02 to 0.04 (dry diameter = 100 nm, hereinafter for Riau peat burning particles, while that for Central Kalimantan ranges from 0.05 to 0.06. Fern combustion particles are more hygroscopic (κ = 0. 08, whereas the acacia burning particles have a mediate κ value (0.04. These results suggest that κ is significantly dependent on biomass types. This variance in κ is partially determined by fractions of water-soluble organic carbon (WSOC, as demonstrated by a correlation analysis (R = 0.65. κ of water-soluble organic matter is also quantified, incorporating the 1-octanol–water partitioning method. κ values for the water extracts are high, especially for peat burning particles (A0 (a whole part of the water-soluble fraction: κ = 0.18, A1 (highly water-soluble fraction: κ = 0.30. This result stresses the importance of both the WSOC fraction and κ of the water-soluble fraction in determining the hygroscopicity of organic aerosol particles. Values of κ correlate positively (R = 0.89 with the fraction of m∕z 44 ion signal quantified using a mass spectrometric technique, demonstrating the importance of highly oxygenated organic compounds to the water uptake by Indonesian BB particles. These results provide an experimentally validated reference for hygroscopicity of organics-dominated particles, thus contributing to more accurate

  3. 3D bioprinting matrices with controlled pore structure and release function guide in vitro self-organization of sweat gland.

    Science.gov (United States)

    Liu, Nanbo; Huang, Sha; Yao, Bin; Xie, Jiangfan; Wu, Xu; Fu, Xiaobing

    2016-10-03

    3D bioprinting matrices are novel platforms for tissue regeneration. Tissue self-organization is a critical process during regeneration that implies the features of organogenesis. However, it is not clear from the current evidences whether 3D printed construct plays a role in guiding tissue self-organization in vitro. Based on our previous study, we bioprinted a 3D matrix as the restrictive niche for direct sweat gland differentiation of epidermal progenitors by different pore structure (300-μm or 400-μm nozzle diameters printed) and reported a long-term gradual transition of differentiated cells into glandular morphogenesis occurs within the 3D construct in vitro. At the initial 14-day culture, an accelerated cell differentiation was achieved with inductive cues released along with gelatin reduction. After protein release completed, the 3D construct guide the self-organized formation of sweat gland tissues, which is similar to that of the natural developmental process. However, glandular morphogenesis was only observed in 300-μm-printed constructs. In the absence of 3D architectural support, glandular morphogenesis was not occurred. This striking finding made us to identify a previously unknown role of the 3D-printed structure in glandular tissue regeneration, and this self-organizing strategy can be applied to forming other tissues in vitro.

  4. QSAR models for the removal of organic micropollutants in four different river water matrices

    KAUST Repository

    Sudhakaran, Sairam; Calvin, James; Amy, Gary L.

    2012-01-01

    Ozonation is an advanced water treatment process used to remove organic micropollutants (OMPs) such as pharmaceuticals and personal care products (PPCPs). In this study, Quantitative Structure Activity Relationship (QSAR) models, for ozonation

  5. Thermodynamic Stability Analysis of Tolbutamide Polymorphs and Solubility in Organic Solvents.

    Science.gov (United States)

    Svärd, Michael; Valavi, Masood; Khamar, Dikshitkumar; Kuhs, Manuel; Rasmuson, Åke C

    2016-06-01

    Melting temperatures and enthalpies of fusion have been determined by differential scanning calorimetry (DSC) for 2 polymorphs of the drug tolbutamide: FI(H) and FV. Heat capacities have been determined by temperature-modulated DSC for 4 polymorphs: FI(L), FI(H), FII, FV, and for the supercooled melt. The enthalpy of fusion of FII at its melting point has been estimated from the enthalpy of transition of FII into FI(H) through a thermodynamic cycle. Calorimetric data have been used to derive a quantitative polymorphic stability relationship between these 4 polymorphs, showing that FII is the stable polymorph below approximately 333 K, above which temperature FI(H) is the stable form up to its melting point. The relative stability of FV is well below the other polymorphs. The previously reported kinetic reversibility of the transformation between FI(L) and FI(H) has been verified using in situ Raman spectroscopy. The solid-liquid solubility of FII has been gravimetrically determined in 5 pure organic solvents (methanol, 1-propanol, ethyl acetate, acetonitrile, and toluene) over the temperature range 278 to 323 K. The ideal solubility has been estimated from calorimetric data, and solution activity coefficients at saturation in the 5 solvents determined. All solutions show positive deviation from Raoult's law, and all van't Hoff plots of solubility data are nonlinear. The solubility in toluene is well below that observed in the other investigated solvents. Solubility data have been correlated and extrapolated to the melting point using a semiempirical regression model. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  6. Charging and exciton-mediated decharging of metal nanoparticles in organic semiconductor matrices

    International Nuclear Information System (INIS)

    Ligorio, Giovanni; Vittorio Nardi, Marco; Christodoulou, Christos; Florea, Ileana; Ersen, Ovidiu; Monteiro, Nicolas-Crespo; Brinkmann, Martin; Koch, Norbert

    2014-01-01

    Gold nanoparticles (Au-NPs) were deposited on the surface of n- and p-type organic semiconductors to form defined model systems for charge storage based electrically addressable memory elements. We used ultraviolet photoelectron spectroscopy to study the electronic properties and found that the Au-NPs become positively charged because of photoelectron emission, evidenced by spectral shifts to higher binding energy. Upon illumination with light that can be absorbed by the organic semiconductors, dynamic charge neutrality of the Au-NPs could be re-established through electron transfer from excitons. The light-controlled charge state of the Au-NPs could add optical addressability to memory elements

  7. High laser-fluence deposition of organic materials in water ice matrices by ''MAPLE''

    DEFF Research Database (Denmark)

    Christensen, Bo Toftmann; Rodrigo, K.; Schou, Jørgen

    2005-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) is a deposition technique for organic material. Water ice was used as a matrix for the biotechnologically important guest material, polyethylene glycol (PEG), for concentrations from 0.5 to 4 wt.%. The target was irradiated with 6 ns laser pulses...

  8. Microstructural control over soluble pentacene deposited by capillary pen printing for organic electronics.

    Science.gov (United States)

    Lee, Wi Hyoung; Min, Honggi; Park, Namwoo; Lee, Junghwi; Seo, Eunsuk; Kang, Boseok; Cho, Kilwon; Lee, Hwa Sung

    2013-08-28

    Research into printing techniques has received special attention for the commercialization of cost-efficient organic electronics. Here, we have developed a capillary pen printing technique to realize a large-area pattern array of organic transistors and systematically investigated self-organization behavior of printed soluble organic semiconductor ink. The capillary pen-printed deposits of organic semiconductor, 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS_PEN), was well-optimized in terms of morphological and microstructural properties by using ink with mixed solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB). Especially, a 1:1 solvent ratio results in the best transistor performances. This result is attributed to the unique evaporation characteristics of the TIPS_PEN deposits where fast evaporation of CB induces a morphological evolution at the initial printed position, and the remaining DCB with slow evaporation rate offers a favorable crystal evolution at the pinned position. Finally, a large-area transistor array was facilely fabricated by drawing organic electrodes and active layers with a versatile capillary pen. Our approach provides an efficient printing technique for fabricating large-area arrays of organic electronics and further suggests a methodology to enhance their performances by microstructural control of the printed organic semiconducting deposits.

  9. New biodegradable organic-soluble chelating agents for simultaneous removal of heavy metals and organic pollutants from contaminated media

    International Nuclear Information System (INIS)

    Ullmann, Amos; Brauner, Neima; Vazana, Shlomi; Katz, Zhanna; Goikhman, Roman; Seemann, Boaz; Marom, Hanit; Gozin, Michael

    2013-01-01

    Highlights: • New soil remediation process using phase transition of partially miscible solvents. • Design and synthesis of new bio-degradable, organic soluble chelating agents. • Feasibility tests of the process on authentically polluted sediments and sludge. • Simultaneous removal of toxic metals and organic pollutants was demonstrated. -- Abstract: Advanced biodegradable and non-toxic organic chelators, which are soluble in organic media, were synthesized on the basis of the S,S-ethylenediamine-disuccinate (S,S-EDDS) ligand. The modifications suggested in this work include attachment of a lipophilic hydrocarbon chain (“tail”) to one or both nitrogen atoms of the S,S-EDDS. The new ligands were designed and evaluated for application in the Sediments Remediation Phase Transition Extraction (SR-PTE) process. This novel process is being developed for the simultaneous removal of both heavy metals and organic pollutants from contaminated soils, sediments or sludge. The new chelators were designed to bind various target metal ions, to promote extraction of these ions into organic solvents. Several variations of attached tails were synthesized and tested. The results for one of them, N,N′-bis-dodecyl-S,S-EDDS (C24-EDDS), showed that the metal-ligand complexes are concentrated in the organic-rich phase in the Phase Transition Extraction process (more than 80%). Preliminary applications of the SR-PTE process with the C24-EDDS ligand were conducted also on actually contaminated sludge (field samples). The extraction of five toxic metals, namely, Cd, Cu, Ni, Pb and Zn was examined. In general, the extraction performance of the new ligand was not less than that of S,S-EDDS when a sufficient ligand-to-extracted ion ratio (about 4:1 was applied

  10. New biodegradable organic-soluble chelating agents for simultaneous removal of heavy metals and organic pollutants from contaminated media

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, Amos, E-mail: Ullmann@eng.tau.ac.il [Faculty of Engineering, School of Mechanical Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Brauner, Neima; Vazana, Shlomi; Katz, Zhanna [Faculty of Engineering, School of Mechanical Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Goikhman, Roman [The Hebrew University of Jerusalem, The Robert H. Smith, Faculty of Agriculture, Food and Environment, Rehovot (Israel); Seemann, Boaz; Marom, Hanit [School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Gozin, Michael, E-mail: cogozin@gmail.com [School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel)

    2013-09-15

    Highlights: • New soil remediation process using phase transition of partially miscible solvents. • Design and synthesis of new bio-degradable, organic soluble chelating agents. • Feasibility tests of the process on authentically polluted sediments and sludge. • Simultaneous removal of toxic metals and organic pollutants was demonstrated. -- Abstract: Advanced biodegradable and non-toxic organic chelators, which are soluble in organic media, were synthesized on the basis of the S,S-ethylenediamine-disuccinate (S,S-EDDS) ligand. The modifications suggested in this work include attachment of a lipophilic hydrocarbon chain (“tail”) to one or both nitrogen atoms of the S,S-EDDS. The new ligands were designed and evaluated for application in the Sediments Remediation Phase Transition Extraction (SR-PTE) process. This novel process is being developed for the simultaneous removal of both heavy metals and organic pollutants from contaminated soils, sediments or sludge. The new chelators were designed to bind various target metal ions, to promote extraction of these ions into organic solvents. Several variations of attached tails were synthesized and tested. The results for one of them, N,N′-bis-dodecyl-S,S-EDDS (C24-EDDS), showed that the metal-ligand complexes are concentrated in the organic-rich phase in the Phase Transition Extraction process (more than 80%). Preliminary applications of the SR-PTE process with the C24-EDDS ligand were conducted also on actually contaminated sludge (field samples). The extraction of five toxic metals, namely, Cd, Cu, Ni, Pb and Zn was examined. In general, the extraction performance of the new ligand was not less than that of S,S-EDDS when a sufficient ligand-to-extracted ion ratio (about 4:1 was applied.

  11. Sorptive and desorptive fractionation of dissolved organic matter by mineral soil matrices.

    Science.gov (United States)

    Oren, Adi; Chefetz, Benny

    2012-01-01

    Interactions of dissolved organic matter (DOM) with soil minerals, such as metal oxides and clays, involve various sorption mechanisms and may lead to sorptive fractionation of certain organic moieties. While sorption of DOM to soil minerals typically involves a degree of irreversibility, it is unclear which structural components of DOM correspond to the irreversibly bound fraction and which factors may be considered determinants. To assist in elucidating that, the current study aimed at investigating fractionation of DOM during sorption and desorption processes in soil. Batch DOM sorption and desorption experiments were conducted with organic matter poor, alkaline soils. Fourier-transform infrared (FTIR) and UV-Vis spectroscopy were used to analyze bulk DOM, sorbed DOM, and desorbed DOM fractions. Sorptive fractionation resulted mainly from the preferential uptake of aromatic, carboxylic, and phenolic moieties of DOM. Soil metal-oxide content positively affected DOM sorption and binding of some specific carboxylate and phenolate functional groups. Desorptive fractionation of DOM was expressed by the irreversible-binding nature of some carboxylic moieties, whereas other bound carboxylic moieties were readily desorbed. Inner-sphere, as opposed to outer-sphere, ligand-exchange complexation mechanisms may be responsible for these irreversible, as opposed to reversible, interactions, respectively. The interaction of aliphatic DOM constituents with soil, presumably through weak van der Waals forces, was minor and increased with increasing proportion of clay minerals in the soil. Revealing the nature of DOM-fractionation processes is of great importance to understanding carbon stabilization mechanisms in soils, as well as the overall fate of contaminants that might be associated with DOM. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Immobilization of low and intermediate level of organic radioactive wastes in cement matrices

    Energy Technology Data Exchange (ETDEWEB)

    Eskander, S.B. [Radioisotopes Department, Atomic Energy Authority, Dokki, Cairo (Egypt); Abdel Aziz, S.M. [Middle Eastern Regional Radioisotope Centre for the Arab Countries, Dokki, Cairo (Egypt); El-Didamony, H. [Faculty of Science, Zagazig University, Zagazig, El-Sharkia (Egypt); Sayed, M.I., E-mail: mois_161272@yahoo.com [Middle Eastern Regional Radioisotope Centre for the Arab Countries, Dokki, Cairo (Egypt)

    2011-06-15

    Highlights: {yields} Solidification/stabilization of liquid scintillation waste. {yields} Resistance to frost attack. {yields} Retarding effect of scintillator waste was overcome by adding clay. {yields} Evaluation of the suitability of cement-clay composite to solidify and stabilize scintillation waste. - Abstract: The adequacy of cement-clay composite, for solidification/stabilization of organic radioactive spent liquid scintillator wastes and its resistance to frost attack were determined by a freezing/thawing (F/T) test. Frost resistance is assessed for the candidate cement-clay composite after 75 cycles of freezing and thawing by evaluating their mass durability index, compressive strength, apparent porosity, volume of open pores, water absorption, and bulk density. Infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) were performed for the final waste form (FWF) before and after the F/T treatment to follow the changes that may take place in its microstructure during the hydration regime. The results were obtained indicate that the candidate composite exhibits acceptable resistance to freeze/thaw treatment and has adequate suitability to solidify and stabilize organic radioactive spent liquid scintillator wastes even at very exaggerating conditions (-50{sup Degree-Sign }C and +60{sup Degree-Sign }C ).

  13. Immobilization of low and intermediate level of organic radioactive wastes in cement matrices

    International Nuclear Information System (INIS)

    Eskander, S.B.; Abdel Aziz, S.M.; El-Didamony, H.; Sayed, M.I.

    2011-01-01

    Highlights: → Solidification/stabilization of liquid scintillation waste. → Resistance to frost attack. → Retarding effect of scintillator waste was overcome by adding clay. → Evaluation of the suitability of cement-clay composite to solidify and stabilize scintillation waste. - Abstract: The adequacy of cement-clay composite, for solidification/stabilization of organic radioactive spent liquid scintillator wastes and its resistance to frost attack were determined by a freezing/thawing (F/T) test. Frost resistance is assessed for the candidate cement-clay composite after 75 cycles of freezing and thawing by evaluating their mass durability index, compressive strength, apparent porosity, volume of open pores, water absorption, and bulk density. Infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM) were performed for the final waste form (FWF) before and after the F/T treatment to follow the changes that may take place in its microstructure during the hydration regime. The results were obtained indicate that the candidate composite exhibits acceptable resistance to freeze/thaw treatment and has adequate suitability to solidify and stabilize organic radioactive spent liquid scintillator wastes even at very exaggerating conditions (-50 ° C and +60 ° C ).

  14. Soluble dendrimers europium(III) β-diketonate complex for organic memory devices

    International Nuclear Information System (INIS)

    Wang Binbin; Fang Junfeng; Li Bin; You Han; Ma Dongge; Hong Ziruo; Li Wenlian; Su Zhongmin

    2008-01-01

    We report the synthesis of a soluble dendrimers europium(III) complex, tris(dibenzoylmethanato)(1,3,5-tris[2-(2'-pyridyl) benzimidazoly]methylbenzene)-europium(III), and its application in organic electrical bistable memory device. Excellent stability that ensured more than 10 6 write-read-erase-reread cycles has been performed in ambient conditions without current-induced degradation. High-density, low-cost memory, good film-firming property, fascinating thermal and morphological stability allow the application of the dendrimers europium(III) complex as an active medium in non-volatile memory devices

  15. Predicting the combinatorial effects of water activity, pH and organic acids on Listeria growth in media and complex food matrices.

    Science.gov (United States)

    Nyhan, L; Begley, M; Mutel, A; Qu, Y; Johnson, N; Callanan, M

    2018-09-01

    The aim of this study was to develop a model to predict growth of Listeria in complex food matrices as a function of pH, water activity and undissociated acetic and propionic acid concentration i.e. common food hurdles. Experimental growth curves of Listeria in food products and broth media were collected from ComBase, the literature and industry sources from which a bespoke secondary gamma model was constructed. Model performance was evaluated by comparing predictions to measured growth rates in growth media (BHI broth) and two adjusted food matrices (zucchini purée and béarnaise sauce). In general, observed growth rates were higher in broth than in the food matrices which resulted in the model over-estimating growth in the adjusted food matrices. In addition, model outputs were more accurate for conditions without acids, indicating that the organic acid component of the model was a source of inaccuracy. In summary, a new predictive growth model for innovating or renovating food products that rely on multi-hurdle technology was created. This study is the first to report on modelling of propionic acid as an inhibitor of Listeria in combination with other hurdles. Our findings provide valuable insights into predictive model design and performance and highlight the importance of experimental validation of models in real food matrices rather than laboratory media alone. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Full evaporation headspace gas chromatography for sensitive determination of high boiling point volatile organic compounds in low boiling matrices.

    Science.gov (United States)

    Mana Kialengila, Didi; Wolfs, Kris; Bugalama, John; Van Schepdael, Ann; Adams, Erwin

    2013-11-08

    Determination of volatile organic components (VOC's) is often done by static headspace gas chromatography as this technique is very robust and combines easy sample preparation with good selectivity and low detection limits. This technique is used nowadays in different applications which have in common that they have a dirty matrix which would be problematic in direct injection approaches. Headspace by nature favors the most volatile compounds, avoiding the less volatile to reach the injector and column. As a consequence, determination of a high boiling solvent in a lower boiling matrix becomes challenging. Determination of VOCs like: xylenes, cumene, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), benzyl alcohol (BA) and anisole in water or water soluble products are an interesting example of the arising problems. In this work, a headspace variant called full evaporation technique is worked out and validated for the mentioned solvents. Detection limits below 0.1 μg/vial are reached with RSD values below 10%. Mean recovery values ranged from 92.5 to 110%. The optimized method was applied to determine residual DMSO in a water based cell culture and DMSO and DMA in tetracycline hydrochloride (a water soluble sample). Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Analytical pyrolysis-based study on intra-skeletal organic matrices from Mediterranean corals.

    Science.gov (United States)

    Adamiano, Alessio; Goffredo, Stefano; Dubinsky, Zvy; Levy, Oren; Fermani, Simona; Fabbri, Daniele; Falini, Giuseppe

    2014-09-01

    Off-line analytical pyrolysis combined with gas chromatography–mass spectroscopy (GC–MS), directly or after trimethylsilylation, along with infrared spectroscopy and amino acid analysis was applied for the first time to the characterization of the intra-skeletal organic matrix (OM) extracted from four Mediterranean hard corals. They were diverse in growth form and trophic strategy namely Balanophyllia europaea and Leptopsammia pruvoti—solitary corals, only the first having zooxanthelle—and Cladocora caespitosa and Astroides calycularis—colonial corals, only the first with zooxanthelle. Pyrolysis products evolved from OM could be assigned to lipid (e.g. fatty acids, fatty alcohols, monoacylglicerols), protein (e.g. 2,5-diketopiperazines, DKPs) and polysaccharide (e.g. anhydrosugars) precursors. Their quantitative distribution showed for all the species a low protein content with respect to lipids and polysaccharides. A chemometric approach using principal component analysis (PCA) and clustering analysis was applied on OM mean amino acidic compositions. The small compositional diversity across coral species was tentatively related with coral growth form. The presence of N-acetyl glucosamine markers suggested a functional link with other calcified tissues containing chitin. The protein fraction was further investigated using novel DKP markers tentatively identified from analytical pyrolysis of model polar linear dipeptides. Again, no correlation was observed in relation to coral ecology. These analytical results revealed that the bulk structure and composition of OMs among studied corals are similar, as it is the textural organization of the skeleton mineralized units. Therefore, they suggest that coral’s biomineralization is governed by similar macromolecules, and probably mechanisms, independently from their ecology.

  18. Micro-scale prediction method for API-solubility in polymeric matrices and process model for forming amorphous solid dispersion by hot-melt extrusion.

    Science.gov (United States)

    Bochmann, Esther S; Neumann, Dirk; Gryczke, Andreas; Wagner, Karl G

    2016-10-01

    A new predictive micro-scale solubility and process model for amorphous solid dispersions (ASDs) by hot-melt extrusion (HME) is presented. It is based on DSC measurements consisting of an annealing step and a subsequent analysis of the glass transition temperature (Tg). The application of a complex mathematical model (BCKV-equation) to describe the dependency of Tg on the active pharmaceutical ingredient (API)/polymer ratio, enables the prediction of API solubility at ambient conditions (25°C). Furthermore, estimation of the minimal processing temperature for forming ASDs during HME trials could be defined and was additionally confirmed by X-ray powder diffraction data. The suitability of the DSC method was confirmed with melt rheological trials (small amplitude oscillatory system). As an example, ball milled physical mixtures of dipyridamole, indomethacin, itraconazole and nifedipine in poly(vinylpyrrolidone-co-vinylacetate) (copovidone) and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus®) were used. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. BODIPY associates in organic matrices: Spectral properties, photostability and evaluation as OLED emitters

    Energy Technology Data Exchange (ETDEWEB)

    Merkushev, D.A.; Usoltsev, S.D. [Ivanovo State University of Chemistry and Technology, Sheremetevskiy Avenue 7, 153000 Ivanovo (Russian Federation); Marfin, Yu.S., E-mail: marfin@isuct.ru [Ivanovo State University of Chemistry and Technology, Sheremetevskiy Avenue 7, 153000 Ivanovo (Russian Federation); Pushkarev, A.P., E-mail: pushkarev@iomc.ras.ru [G.A. Razuvaev Institute of Organometallic Chemistry RAS, Tropinina 49, 603950 Nizhny Novgorod (Russian Federation); Volyniuk, D.; Grazulevicius, J.V. [Department of Polymer Chemistry and Technology, Kaunas University of Technology, Radvilenu pl. 19, LT-50254 Kaunas (Lithuania); Rumyantsev, E.V. [Ivanovo State University of Chemistry and Technology, Sheremetevskiy Avenue 7, 153000 Ivanovo (Russian Federation)

    2017-02-01

    In the present study four BODIPY (boron dipyrromethene: 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) dyes with π-extended substituents in C-8 position were investigated in solvents and polymer mediums. High aggregation degree was observed for the dyes in the solid state. Association and twisted intramolecular charge transfer processes were found to affect the spectral properties of the compounds causing bathochromic shifts in absorption and fluorescence spectra. The extension of substituent π-conjugation gains molecular association evoked presumably by π-π interaction between the substituents of the adjacent molecules. Photostability of the complexes in different forms was analyzed and the distorted form stabilized by polymer matrix was found to be the most stable. The substituent nature did not affect strongly the photostability of dyes. Displacement of monomer-associate equilibrium in hybrid materials with polymethylmethacrylate and poly(9-vinylcarbazole) was exploited for tuning spectral characteristics of the materials. Two dyes readily forming aggregates at the lowest concentrations were applied for the fabrication of organic light-emitting diodes. The fabricated devices exhibited electroluminescence in the appropriate spectral ranges with moderate efficiency. - Highlights: • Four BODIPY dyes with π-extended substituents in 8-position were investigated in solvents and polymers. • Substituent influence on photophysical properties and photostability of the compounds are discussed. • Aggregation induced spectral changes were observed. • Displacement of monomer-aggregate equilibrium was exploited for tuning electroluminescent characteristics of OLED devices.

  20. Organic-soluble lanthanide nuclear magnetic resonance shift reagents for sulfonium and isothiouronium salts

    International Nuclear Information System (INIS)

    Wenzel, T.J.; Zaia, J.

    1987-01-01

    Lanthanide complexes of the formula [Ln(fod) 4 ] - (FOD, 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione) are effective organic-soluble nuclear magnetic resonance shift reagents for sulfonium and isothiouronium salts. The shift reagent is formed in solution from Ln(fod) 3 and Ag(fod) or K(fod). The selection of Ag(fod) or K(fod) in forming the shift reagent is dependent on the anion of the organic salt. Ag(fod) is more effective with halide salts, whereas K(fod) is preferred with tetrafluoroborate salts. Resolution of diastereotopic hydrogen atoms was observed in the shifted spectra of certain substrates. Enantiomeric resolution was obtained in the spectrum of sec-butylisothiouronium chloride with a chiral shift reagent. The reagents can be employed in solvents such as chloroform and benzene

  1. Self-organization in a simple model of adaptive agents playing 2 x 2 games with arbitrary payoff matrices.

    Science.gov (United States)

    Fort, H; Viola, S

    2004-03-01

    We analyze, both analytically and numerically, the self-organization of a system of "selfish" adaptive agents playing an arbitrary iterated pairwise game (defined by a 2 x 2 payoff matrix). Examples of possible games to play are the prisoner's dilemma (PD) game, the chicken game, the hero game, etc. The agents have no memory, use strategies not based on direct reciprocity nor "tags" and are chosen at random, i.e., geographical vicinity is neglected. They can play two possible strategies: cooperate (C) or defect (D). The players measure their success by comparing their utilities with an estimate for the expected benefits and update their strategy following a simple rule. Two versions of the model are studied: (1) the deterministic version (the agents are either in definite states C or D) and (2) the stochastic version (the agents have a probability c of playing C). Using a general master equation we compute the equilibrium states into which the system self-organizes, characterized by their average probability of cooperation c(eq). Depending on the payoff matrix, we show that c(eq) can take five different values. We also consider the mixing of agents using two different payoff matrices and show that any value of c(eq) can be reached by tuning the proportions of agents using each payoff matrix. In particular, this can be used as a way to simulate the effect of a fraction d of "antisocial" individuals--incapable of realizing any value to cooperation--on the cooperative regime hold by a population of neutral or "normal" agents.

  2. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Science.gov (United States)

    Jing, Bo; Wang, Zhen; Tan, Fang; Guo, Yucong; Tong, Shengrui; Wang, Weigang; Zhang, Yunhong; Ge, Maofa

    2018-04-01

    While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO3)2) and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA). The nitrate salt / organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH), the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  3. Hygroscopic behavior of atmospheric aerosols containing nitrate salts and water-soluble organic acids

    Directory of Open Access Journals (Sweden)

    B. Jing

    2018-04-01

    Full Text Available While nitrate salts have critical impacts on environmental effects of atmospheric aerosols, the effects of coexisting species on hygroscopicity of nitrate salts remain uncertain. The hygroscopic behaviors of nitrate salt aerosols (NH4NO3, NaNO3, Ca(NO32 and their internal mixtures with water-soluble organic acids were determined using a hygroscopicity tandem differential mobility analyzer (HTDMA. The nitrate salt ∕ organic acid mixed aerosols exhibit varying phase behavior and hygroscopic growth depending upon the type of components in the particles. Whereas pure nitrate salt particles show continuous water uptake with increasing relative humidity (RH, the deliquescence transition is still observed for ammonium nitrate particles internally mixed with organic acids such as oxalic acid and succinic acid with a high deliquescence point. The hygroscopicity of submicron aerosols containing sodium nitrate and an organic acid is also characterized by continuous growth, indicating that sodium nitrate tends to exist in a liquid-like state under dry conditions. It is observed that in contrast to the pure components, the water uptake is hindered at low and moderate RH for calcium nitrate particles containing malonic acid or phthalic acid, suggesting the potential effects of mass transfer limitation in highly viscous mixed systems. Our findings improve fundamental understanding of the phase behavior and water uptake of nitrate-salt-containing aerosols in the atmospheric environment.

  4. Infrared spectra of complex organic molecules in astronomically relevant ice matrices. I. Acetaldehyde, ethanol, and dimethyl ether

    Science.gov (United States)

    Terwisscha van Scheltinga, J.; Ligterink, N. F. W.; Boogert, A. C. A.; van Dishoeck, E. F.; Linnartz, H.

    2018-03-01

    Context. The number of identified complex organic molecules (COMs) in inter- and circumstellar gas-phase environments is steadily increasing. Recent laboratory studies show that many such species form on icy dust grains. At present only smaller molecular species have been directly identified in space in the solid state. Accurate spectroscopic laboratory data of frozen COMs, embedded in ice matrices containing ingredients related to their formation scheme, are still largely lacking. Aim. This work provides infrared reference spectra of acetaldehyde (CH3CHO), ethanol (CH3CH2OH), and dimethyl ether (CH3OCH3) recorded in a variety of ice environments and for astronomically relevant temperatures, as needed to guide or interpret astronomical observations, specifically for upcoming James Webb Space Telescope observations. Methods: Fourier transform transmission spectroscopy (500-4000 cm-1/20-2.5 μm, 1.0 cm-1 resolution) was used to investigate solid acetaldehyde, ethanol and dimethyl ether, pure or mixed with water, CO, methanol, or CO:methanol. These species were deposited on a cryogenically cooled infrared transmissive window at 15 K. A heating ramp was applied, during which IR spectra were recorded until all ice constituents were thermally desorbed. Results: We present a large number of reference spectra that can be compared with astronomical data. Accurate band positions and band widths are provided for the studied ice mixtures and temperatures. Special efforts have been put into those bands of each molecule that are best suited for identification. For acetaldehyde the 7.427 and 5.803 μm bands are recommended, for ethanol the 11.36 and 7.240 μm bands are good candidates, and for dimethyl ether bands at 9.141 and 8.011 μm can be used. All spectra are publicly available in the Leiden Database for Ice.

  5. Soluble CD30 serum level--an adequate marker for allograft rejection of solid organs?

    Science.gov (United States)

    Schlaf, G; Altermann, W W; Rothhoff, A; Seliger, B

    2007-11-01

    The CD30 molecule, a 120 kDa cell surface glycoprotein, is a member of the tumor necrosis factor receptor (TNF-R) superfamily and was originally identified on the surface of Reed-Sternberg cells and anaplastic large cell lymphomas in Hodgkin's disease patients. In addition to lymphoproliferative disorders the expression of CD30 was found in both activated CD8+ and CD4+ Th2 cells which lead to the activation of B-cells and consequently to the inhibition of the Th1-type cellular immunity. The membrane-bound CD30 molecule can be proteolytically cleaved, thereby generating a soluble form (sCD30) of about 85 kDa. Low serum levels of soluble CD30 were found in healthy humans, whereas increased sCD30 serum concentrations were detected under pathophysiological situations such as systemic lupus erythematosus, rheumatoid arthritis, certain viral infections and adult T cell leukaemia/lymphoma. In addition, it has recently been suggested that pre- or post-transplant levels of sCD30 represent a biomarker for graft rejection associated with an impaired outcome for transplanted patients. We here review (i) the current knowledge of the clinical significance of sCD30 serum levels for solid organ transplantations and (ii) our own novel data regarding inter- and intra-individual variations as well as time-dependent alterations of sCD30 levels in patients. (iii) Based on this information the implementation of sCD30 as predictive pre-transplant or post-transplant parameter for solid organ transplantation is critically discussed.

  6. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Directory of Open Access Journals (Sweden)

    Lei Gao

    Full Text Available Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL 'SW' (in the '203Z' background were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy, sucrose-phosphate synthase (SPSs, insoluble acid invertases (IAI, NAD-dependent malate dehydrogenase (NAD-cyt MDH, aluminum-activated malate transporter (ALMT, and citrate synthase (CS. This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  7. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon.

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling; Liu, Wenge

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar '203Z' and its near-isogenic line (NIL) 'SW' (in the '203Z' background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening.

  8. Comparative transcriptome analysis reveals key genes potentially related to soluble sugar and organic acid accumulation in watermelon

    Science.gov (United States)

    Gao, Lei; Zhao, Shengjie; Lu, Xuqiang; He, Nan; Zhu, Hongju; Dou, Junling

    2018-01-01

    Soluble sugars and organic acids are important components of fruit flavor and have a strong impact on the overall organoleptic quality of watermelon (Citrullus lanatus) fruit. Several studies have analyzed the expression levels of the genes related to soluble sugar accumulation and the dynamic changes in their content during watermelon fruit development and ripening. Nevertheless, to date, there have been no reports on the organic acid content in watermelon or the genes regulating their synthesis. In this study, the soluble sugars and organic acids in watermelon were measured and a comparative transcriptome analysis was performed to identify the key genes involved in the accumulation of these substances during fruit development and ripening. The watermelon cultivar ‘203Z’ and its near-isogenic line (NIL) ‘SW’ (in the ‘203Z’ background) were used as experimental materials. The results suggested that soluble sugar consist of fructose, glucose and sucrose while malic-, citric-, and oxalic acids are the primary organic acids in watermelon fruit. Several differentially expressed genes (DEGs) related to soluble sugar- and organic acid accumulation and metabolism were identified. These include the DEGs encoding raffinose synthase, sucrose synthase (SuSy), sucrose-phosphate synthase (SPSs), insoluble acid invertases (IAI), NAD-dependent malate dehydrogenase (NAD-cyt MDH), aluminum-activated malate transporter (ALMT), and citrate synthase (CS). This is the first report addressing comparative transcriptome analysis via NILs materials in watermelon fruit. These findings provide an important basis for understanding the molecular mechanism that leads to soluble sugar and organic acid accumulation and metabolism during watermelon fruit development and ripening. PMID:29324867

  9. Formal matrices

    CERN Document Server

    Krylov, Piotr

    2017-01-01

    This monograph is a comprehensive account of formal matrices, examining homological properties of modules over formal matrix rings and summarising the interplay between Morita contexts and K theory. While various special types of formal matrix rings have been studied for a long time from several points of view and appear in various textbooks, for instance to examine equivalences of module categories and to illustrate rings with one-sided non-symmetric properties, this particular class of rings has, so far, not been treated systematically. Exploring formal matrix rings of order 2 and introducing the notion of the determinant of a formal matrix over a commutative ring, this monograph further covers the Grothendieck and Whitehead groups of rings. Graduate students and researchers interested in ring theory, module theory and operator algebras will find this book particularly valuable. Containing numerous examples, Formal Matrices is a largely self-contained and accessible introduction to the topic, assuming a sol...

  10. Organic compounds in hot-water-soluble fractions from water repellent soils

    Science.gov (United States)

    Atanassova, Irena; Doerr, Stefan

    2014-05-01

    Water repellency (WR) is a soil property providing hydrophobic protection and preventing rapid microbial decomposition of organic matter entering the soil with litter or plant residues. Global warming can cause changes in WR, thus influencing water storage and plant productivity. Here we assess two different approaches for analysis of organic compounds composition in hot water extracts from accelerated solvent extraction (ASE) of water repellent soils. Extracts were lyophilized, fractionated on SiO2 (sand) and SPE cartridge, and measured by GC/MS. Dominant compounds were aromatic acids, short chain dicarboxylic acids (C4-C9), sugars, short chain fatty acids (C8-C18), and esters of stearic and palmitic acids. Polar compounds (mainly sugars) were adsorbed on applying SPE clean-up procedure, while esters were highly abundant. In addition to the removal of polar compounds, hydrophobic esters and hydrocarbons (alkanes and alkenes particle wettability and C dynamics in soils. Key words: soil water repellency, hot water soluble carbon (HWSC), GC/MS, hydrophobic compounds

  11. Soluble carbon in oxisol under the effect of organic residue rates

    Directory of Open Access Journals (Sweden)

    Gabriela Lúcia Pinheiro

    2014-06-01

    Full Text Available The application of organic residues to the soil can increase soluble organic carbon (SOC and affect the pH and electrolytic conductivity (EC of the soil. However, the magnitude of these changes depends on the type of residue and the applied dose. This study aimed to evaluate the effect of increasing C rates contained in organic residue on the pH, EC, water-extractable total carbon (WETC, water-extractable organic carbon (WEOC, and water-extractable inorganic carbon (WEIC in soil treated with manure (chicken, swine, and quail, sawdust, coffee husk, and sewage sludge. The levels of total C (TC- KH2PO4, organic carbon (OC- KH2PO4, and inorganic C (IC- KH2PO4 extractable by a 0.1 mol L-1 KH2PO4 solution were also quantified in soil under the effect of increasing rates of chicken and quail manures. The following rates of organic residue C were applied to a dystrophic Red Latosol (Oxisol sample: 0, 2,000, 5,000, 10,000, and 20,000 mg kg-1. The addition of organic residues to the soil increased pH, except in the case of sewage sludge, which acidified the soil. The acidity correction potential of chicken and quail manure was highest, dependent on the manure rate applied; regardless of the dose used, sawdust barely alters the soil pH. At all tested rates, the EC of the soil treated with swine manure, coffee husk, and sawdust remained below 2.0 dS m-1, which is a critical level for salinity-sensitive crops. However, the application of chicken or quail manure and sewage sludge at certain rates increased the EC to values above this threshold level. Highest levels of WETC, WEOC, and WEIC were obtained when chicken and quail manure and coffee husk were applied to the Oxisol. The quantities of SOC extracted by KH2PO4 were higher than the quantities extracted by water, demonstrating the ability of soil to adsorb C into its colloids.

  12. Averaging operations on matrices

    Indian Academy of Sciences (India)

    2014-07-03

    Jul 3, 2014 ... Role of Positive Definite Matrices. • Diffusion Tensor Imaging: 3 × 3 pd matrices model water flow at each voxel of brain scan. • Elasticity: 6 × 6 pd matrices model stress tensors. • Machine Learning: n × n pd matrices occur as kernel matrices. Tanvi Jain. Averaging operations on matrices ...

  13. Large contribution of fossil fuel derived secondary organic carbon to water soluble organic aerosols in winter haze in China

    Directory of Open Access Journals (Sweden)

    Y.-L. Zhang

    2018-03-01

    Full Text Available Water-soluble organic carbon (WSOC is a large fraction of organic aerosols (OA globally and has significant impacts on climate and human health. The sources of WSOC remain very uncertain in polluted regions. Here we present a quantitative source apportionment of WSOC, isolated from aerosols in China using radiocarbon (14C and offline high-resolution time-of-flight aerosol mass spectrometer measurements. Fossil emissions on average accounted for 32–47 % of WSOC. Secondary organic carbon (SOC dominated both the non-fossil and fossil derived WSOC, highlighting the importance of secondary formation to WSOC in severe winter haze episodes. Contributions from fossil emissions to SOC were 61 ± 4 and 50 ± 9 % in Shanghai and Beijing, respectively, significantly larger than those in Guangzhou (36 ± 9 % and Xi'an (26 ± 9 %. The most important primary sources were biomass burning emissions, contributing 17–26 % of WSOC. The remaining primary sources such as coal combustion, cooking and traffic were generally very small but not negligible contributors, as coal combustion contribution could exceed 10 %. Taken together with earlier 14C source apportionment studies in urban, rural, semi-urban and background regions in Asia, Europe and the USA, we demonstrated a dominant contribution of non-fossil emissions (i.e., 75 ± 11 % to WSOC aerosols in the Northern Hemisphere; however, the fossil fraction is substantially larger in aerosols from East Asia and the eastern Asian pollution outflow, especially during winter, due to increasing coal combustion. Inclusion of our findings can improve a modelling of effects of WSOC aerosols on climate, atmospheric chemistry and public health.

  14. Large contribution of fossil fuel derived secondary organic carbon to water soluble organic aerosols in winter haze in China

    Science.gov (United States)

    Zhang, Yan-Lin; El-Haddad, Imad; Huang, Ru-Jin; Ho, Kin-Fai; Cao, Jun-Ji; Han, Yongming; Zotter, Peter; Bozzetti, Carlo; Daellenbach, Kaspar R.; Slowik, Jay G.; Salazar, Gary; Prévôt, André S. H.; Szidat, Sönke

    2018-03-01

    Water-soluble organic carbon (WSOC) is a large fraction of organic aerosols (OA) globally and has significant impacts on climate and human health. The sources of WSOC remain very uncertain in polluted regions. Here we present a quantitative source apportionment of WSOC, isolated from aerosols in China using radiocarbon (14C) and offline high-resolution time-of-flight aerosol mass spectrometer measurements. Fossil emissions on average accounted for 32-47 % of WSOC. Secondary organic carbon (SOC) dominated both the non-fossil and fossil derived WSOC, highlighting the importance of secondary formation to WSOC in severe winter haze episodes. Contributions from fossil emissions to SOC were 61 ± 4 and 50 ± 9 % in Shanghai and Beijing, respectively, significantly larger than those in Guangzhou (36 ± 9 %) and Xi'an (26 ± 9 %). The most important primary sources were biomass burning emissions, contributing 17-26 % of WSOC. The remaining primary sources such as coal combustion, cooking and traffic were generally very small but not negligible contributors, as coal combustion contribution could exceed 10 %. Taken together with earlier 14C source apportionment studies in urban, rural, semi-urban and background regions in Asia, Europe and the USA, we demonstrated a dominant contribution of non-fossil emissions (i.e., 75 ± 11 %) to WSOC aerosols in the Northern Hemisphere; however, the fossil fraction is substantially larger in aerosols from East Asia and the eastern Asian pollution outflow, especially during winter, due to increasing coal combustion. Inclusion of our findings can improve a modelling of effects of WSOC aerosols on climate, atmospheric chemistry and public health.

  15. Soluble organic additive effects on stress development during drying of calcium carbonate suspensions.

    Science.gov (United States)

    Wedin, Pär; Lewis, Jennifer A; Bergström, Lennart

    2005-10-01

    The effect of polymer, plasticizer, and surfactant additives on stress development during drying of calcium carbonate particulate coatings was studied using a controlled-environment apparatus that simultaneously monitors drying stress, weight loss, and relative humidity. We found that the calcium carbonate coatings display a drying stress evolution typical of granular films, which is characterized by a sharp capillary-induced stress rise followed by a rapid stress relaxation. The addition of a soluble polymer to the CaCO3 suspension resulted in a two-stage stress evolution process. The initial stress rise stems from capillary-pressure-induced stresses within the film, while the second, larger stress rise occurs due to solidification and shrinkage of the polymeric species. Measurements on the corresponding pure polymer solutions established a clear correlation between the magnitude of residual stress in both the polymer and CaCO3-polymer films to the physical properties of the polymer phase, i.e. its glass transition temperature, T(g), and Young's modulus. The addition of small organic molecules can reduce the residual stress observed in the CaCO3-polymer films; e.g., glycerol, which acts as a plasticizer, reduces the drying stress by lowering T(g), while surfactant additions reduce the surface tension of the liquid phase, and, hence, the magnitude of the capillary pressure within the film.

  16. Linear correlation of interfacial tension at water-solvent interface, solubility of water in organic solvents, and SE* scale parameters

    International Nuclear Information System (INIS)

    Mezhov, E.A.; Khananashvili, N.L.; Shmidt, V.S.

    1988-01-01

    A linear correlation has been established between the solubility of water in water-immiscible organic solvents and the interfacial tension at the water-solvent interface on the one hand and the parameters of the SE* and π* scales for these solvents on the other hand. This allows us, using the known tabulated SE* or π* parameters for each solvent, to predict the values of the interfacial tension and the solubility of water for the corresponding systems. We have shown that the SE* scale allows us to predict these values more accurately than other known solvent scales, since in contrast to other scales it characterizes solvents found in equilibrium with water

  17. Photochemical Degradation of Petroleum-Derived Water-Soluble Organics into the Background Dissolved Organic Carbon Pool

    Science.gov (United States)

    Podgorski, D. C.; Ray, P. Z.; Roland, N. V.; Corilo, Y. E.; Tarr, M. A.; Guillemette, F.; Spencer, R. G.

    2016-02-01

    Water-soluble organic (WSO) photoproducts produced from Macondo crude oil (MC252) and a heavy fuel oil (HFO), a surrogate for that which was spilled into the San Francisco Bay by the M/V Cosco Busan, were isolated and irradiated with simulated sunlight to examine the photochemical fate of the products in aquatic ecosystems. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) reveals marked transformations in the elemental composition of WSOs at specific irradiation periods across a time series that correspond with shifts in bulk properties determined with optical measurements. Blue shifts in EEMs spectra correlate with an increase in formulas classified as unsaturated, high oxygen while the polyphenols and unsaturated, low oxygen compounds decrease. The characteristic A and C humic- and fulvic-like FDOM signatures begin to appear in the EEM spectra of WSOs that were irradiated for as little as 8 to 12 hours, the equivalent of 2 to 3 days of natural sunlight. The presence of the A and C signatures correlate to elemental compositions that exhibit a further decrease in the unsaturated, low oxygen and subsequent increase of unsaturated, high oxygen and highly oxygenated aliphatic compounds. Furthermore, van Krevelen plots reveal a shift toward the compositional space associated with carboxyl-rich aromatic moieties (CRAM) as a function of irradiation period and the appearance of the humic- and fulvic-like FDOM signatures in the EEM spectra. Although the photodegraded WSO products show similarities in FDOM and elemental composition to representative natural dissolved organic matter from their respective pools, persistent petroleum signatures that are not photoactive are still detected. Future studies are required to examine the bioavailability of these photodegraded WSO products to determine if they degrade or persist in the environment.

  18. Fermentation of calcium-fortified soymilk with Lactobacillus: effects on calcium solubility, isoflavone conversion, and production of organic acids.

    Science.gov (United States)

    Tang, A L; Shah, N P; Wilcox, G; Walker, K Z; Stojanovska, L

    2007-11-01

    The objective of this study was to enhance calcium solubility and bioavailability from calcium-fortified soymilk by fermentation with 7 strains of Lactobacillus, namely, L. acidophilus ATCC 4962, ATCC33200, ATCC 4356, ATCC 4461, L. casei ASCC 290, L. plantarum ASCC 276, and L. fermentum VRI-003. The parameters that were used are viability, pH, calcium solubility, organic acid, and biologically active isoflavone aglycone content. Calcium-fortified soymilk made from soy protein isolate was inoculated with these probiotic strains, incubated for 24 h at 37 degrees C, then stored for 14 d at 4 degrees C. Soluble calcium was measured using atomic absorption spectrophotometry (AA). Organic acids and bioactive isoflavone aglycones, including diadzein, genistein, and glycetein, were measured using HPLC. Viability of the strains in the fermented calcium-fortified soymilk was > 8.5 log(10) CFU/g after 24 h fermentation and this was maintained for 14-d storage at 4 degrees C. After 24 h, there was a significant increase (P casei ASCC 290 demonstrated the highest increase with 89.3% and 87.0% soluble calcium after 24 h, respectively. The increase in calcium solubility observed was related to lowered pH associated with production of lactic and acetic acids. Fermentation significantly increased (P < 0.05) the level of conversion of isoflavones into biologically active aglycones, including diadzein, genistein, and glycetein. Our results show that fermenting calcium-fortified soymilk with the selected probiotics can potentially enhance the calcium bioavailability of calcium-fortified soymilk due to increased calcium solubility and bioactive isoflavone aglycone enrichment.

  19. High mobility organic field-effect transistor based on water-soluble deoxyribonucleic acid via spray coating

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wei; Han, Shijiao; Huang, Wei; Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2015-01-26

    High mobility organic field-effect transistors (OFETs) by inserting water-soluble deoxyribonucleic acid (DNA) buffer layer between electrodes and pentacene film through spray coating process were fabricated. Compared with the OFETs incorporated with DNA in the conventional organic solvents of ethanol and methanol: water mixture, the water-soluble DNA based OFET exhibited an over four folds enhancement of field-effect mobility from 0.035 to 0.153 cm{sup 2}/Vs. By characterizing the surface morphology and the crystalline structure of pentacene active layer through atomic force microscope and X-ray diffraction, it was found that the adoption of water solvent in DNA solution, which played a key role in enhancing the field-effect mobility, was ascribed to both the elimination of the irreversible organic solvent-induced bulk-like phase transition of pentacene film and the diminution of a majority of charge trapping at interfaces in OFETs.

  20. Thermodynamic properties of solubility of 2-methyl-5-arylfuran-3-carboxylic acids in organic solvents

    Czech Academy of Sciences Publication Activity Database

    Sobechko, I.; Dibrivnyi, V.; Horak, Y.; Velychkivska, Nadiia; Kochubei, V.; Obushak, M.

    2017-01-01

    Roč. 11, č. 4 (2017), s. 397-404 ISSN 1996-4196 Institutional support: RVO:61389013 Keywords : enthalpy * entropy * Gibbs energy of solubility Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science

  1. Correlations between water-soluble organic aerosol and water vapor: a synergistic effect from biogenic emissions?

    Science.gov (United States)

    Hennigan, Christopher J; Bergin, Michael H; Weber, Rodney J

    2008-12-15

    Ground-based measurements of meteorological parameters and water-soluble organic carbon in the gas(WSOCg) and particle (WSOCp) phases were carried out in Atlanta, Georgia, from May to September 2007. Fourteen separate events were observed throughout the summer in which WSOCp and water vapor concentrations were highly correlated (average WSOCp-water vapor r = 0.92); however, for the entire summer, no well-defined relationship existed between the two. The correlation events, which lasted on average 19 h, were characterized by a wide range of WSOCp and water vapor concentrations. Several hypotheses for the correlation are explored, including heterogeneous liquid phase SOA formation and the co-emission of biogenic VOCs and water vapor. The data provide supporting evidence for contributions from both and suggest the possibility of a synergistic effect between the co-emission of water vapor and VOCs from biogenic sources on SOA formation. Median WSOCp concentrations were also correlated with elemental carbon (EC), although this correlation extended over the entire summer. Despite the emission of water vapor from anthropogenic mobile sources and the WSOCp-EC correlation, mobile sources were not considered a potential cause for the WSOCp-water vapor correlations because of their low contribution to the water vapor budget. Meteorology could perhaps have influenced the WSOCp-EC correlation, but other factors are implicated as well. Overall, the results suggest that the temperature-dependent co-emission of water vapor through evapotranspiration and SOA precursor-VOCs by vegetation may be an important process contributing to SOA in some environments.

  2. An odd–even effect on solubility of dicarboxylic acids in organic solvents

    International Nuclear Information System (INIS)

    Zhang, Hui; Yin, Qiuxiang; Liu, Zengkun; Gong, Junbo; Bao, Ying; Zhang, Meijing; Hao, Hongxun; Hou, Baohong; Xie, Chuang

    2014-01-01

    Highlights: • The solubilities of the homologous series of C2–C10 dicarboxylic acids were determined in four selected solvents. • The experimental data were well correlated with the modified Apelblat equation. • The odd–even effect of solubility was found and explained. • The enthalpy, entropy and the molar Gibbs free energy of solution were predicted. - Abstract: The solubility of the homologous series of dicarboxylic acids, HOOC-(CH 2 ) n−2 -COOH (n = 2 to 10), in ethanol, acetic acid, acetone and ethyl acetate was measured at temperatures ranging from (278.15 to 323.15) K by a static analytic method at atmospheric pressure. Dicarboxylic acids with even number of carbon atoms exhibit lower values of solubility than adjacent homologues with odd carbon numbers. This odd–even effect of solubility is attributed to the twist of molecules and interlayer packing in solid state as explained in our previous work. The alternation varies in different solvents, which is believed to be associated with the properties of solvents. Finally, the dissolution enthalpy, dissolution entropy and the molar Gibbs free energy were calculated using the fitting parameters of the modified Apelblat equation. The molar Gibbs free energy also showed apparent odd–even alternation in keeping with the alternation of solubility

  3. Methods for calculation of engineering parameters for gas separation. [vapor pressure and solubility of gases in organic liquids

    Science.gov (United States)

    Lawson, D. D.

    1979-01-01

    A group additivity method is generated which allows estimation, from the structural formulas alone, of the energy of vaporization and the molar volume at 25 C of many nonpolar organic liquids. Using these two parameters and appropriate thermodynamic relations, the vapor pressure of the liquid phase and the solubility of various gases in nonpolar organic liquids are predicted. It is also possible to use the data to evaluate organic and some inorganic liquids for use in gas separation stages or liquids as heat exchange fluids in prospective thermochemical cycles for hydrogen production.

  4. Effect of radio-oxidative ageing and pH on the release of soluble organic matter from bitumen

    International Nuclear Information System (INIS)

    Libert, M.F.; Walczak, I.

    2000-01-01

    Bitumen is employed as an embedding matrix for low and medium level radioactive wastes. An high impermeability and a great resistance against most of chemicals are two of main bitumen properties. These characteristics of bitumen confinement properties may be modified under environmental parameters during intermediate storage or deep repository such as radiations or the presence of water. The radio-oxidation induces an increase of the quantity of leached organic matter. The evolution of the soluble organic species release seems to be linear with the irradiation dose, as soon as the dose is higher than 20 kGy, and seems to be no dependant of the dose rate. The generation of water-soluble organic complexing agents can affect the integrity of the wasteform due to an increase of the radionuclides solubility. An increase of the quantity of leached organic matter is also observed in presence of alkaline solutions. Identified molecules, by GC/MS analysis, are aromatics like naphthalene, oxidised compounds like alcohols, linear carbonyls, aromatics, glycols and nitrogen compounds. (authors)

  5. Spectroscopic study of the water-soluble organic matter isolated from atmospheric aerosols collected under different atmospheric conditions

    International Nuclear Information System (INIS)

    Duarte, Regina M.B.O.; Pio, Casimiro A.; Duarte, Armando C.

    2005-01-01

    The composition of the water-soluble organic matter from fine aerosols collected in a rural location during two different meteorological conditions (summer and autumn) was investigated by UV-vis, synchronous fluorescence (with Δλ = 20 nm), FT-IR and CPMAS- 13 C NMR spectroscopies. A seasonal variation in the concentration of total carbon, organic carbon and water-soluble organic carbon was confirmed, with higher values during the autumn and lower values during the summer season. The chemical characterisation of the water-soluble organic matter showed that both samples are dominated by a high content of aliphatic structures, carboxyl groups and aliphatic carbons single bonded to one oxygen or nitrogen atom. However, the autumn sample exhibits a higher aromatic content than the summer sample, plus signals due to carbons of phenol, ketones and methoxyl groups. These signals were attributed to lignin breakdown products which are likely to be released during wood combustion processes. The obtained results put into evidence the major contribution of biomass burning processes in domestic fireplaces during low temperature conditions into both the concentration and the bulk chemical properties of the WSOC from fine aerosols

  6. Photoautotrophic Production of Biomass, Laurate, and Soluble Organics by Synechocystis sp. PCC 6803

    Science.gov (United States)

    Nguyen, Binh Thanh

    Photosynthesis converts sunlight to biomass at a global scale. Among the photosynthetic organisms, cyanobacteria provide an excellent model to study how photosynthesis can become a practical platform of large-scale biotechnology. One novel approach involves metabolically engineering the cyanobacterium Synechocystis sp. PCC 6803 to excrete laurate, which is harvested directly. This work begins by defining a working window of light intensity (LI). Wild-type and laurate-excreting Synechocystis required an LI of at least 5 muE/m2-s to sustain themselves, but are photo-inhibited by LI of 346 to 598 muE/m2-s. Fixing electrons into valuable organic products, e.g., biomass and excreted laurate, is critical to success. Wild-type Synechocystis channeled 75% to 84% of its fixed electrons to biomass; laurate-excreting Synechocystis fixed 64 to 69% as biomass and 6.6% to 10% as laurate. This means that 16 to 30% of the electrons were diverted to non-valuable soluble products, and the trend was accentuated with higher LI. How the Ci concentration depended on the pH and the nitrogen source was quantified by the proton condition and experimentally validated. Nitrate increased, ammonium decreased, but ammonium nitrate stabilized alkalinity and Ci. This finding provides a mechanistically sound tool to manage Ci and pH independently. Independent evaluation pH and Ci on the growth kinetics of Synechocystis showed that pH 8.5 supported the fastest maximum specific growth rate (mumax): 2.4/day and 1.7/day, respectively, for the wild type and modified strains with LI of 202 muE/m2-s. Half-maximum-rate concentrations (KCi) were less than 0.1 mM, meaning that Synechocystis should attain its mumax with a modest Ci concentration (≥1.0 mM). Biomass grown with day-night cycles had a night endogenous decay rate of 0.05-1.0/day, with decay being faster with higher LI and the beginning of dark periods. Supplying light at a fraction of daylight reduced dark decay rate and improved overall

  7. Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols.

    Science.gov (United States)

    Yu, Xue-Chun; He, Ke-Bin; Ma, Yong-Liang; Yang, Fu-Mo; Duan, Feng-Kui; Zheng, Ai-Hua; Zhao, Cheng-Yi

    2004-01-01

    A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F- , Cl- , NO2(-), NO3(-), SO3(2-), SO4(2-) , PO4(3-)), and fifteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 microg/m3 to 500 microg/m3 ( r = 0.999-0.9999). The relative standard deviation (RSD) were 0.43%-2.00% and the detection limits were from 2.7 ng/m3 to 88 ng/m3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM2.5 of Beijing.

  8. Effect of anthropogenic organic complexants on the solubility of Ni, Th, U(IV) and U(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Felipe-Sotelo, M., E-mail: m.felipe-sotelo@lboro.ac.uk [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Edgar, M. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Beattie, T. [MCM Consulting. Täfernstrasse 11, CH 5405 Baden-Dättwil (Switzerland); Warwick, P. [Enviras Ltd., LE11 3TU Loughborough, Leicestershire (United Kingdom); Evans, N.D.M.; Read, D. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom)

    2015-12-30

    Highlights: • Citrate increases the solubility of Ni, Th and U between 3 and 4 orders of magnitude. • Theophrastite is the solubility controlling phase of Ni in 95%-saturated Ca(OH){sub 2}. • U(VI) and Ni may form Metal-citrate-OH complexes stabilised by the presence of Ca{sup 2+}. - Abstract: The influence of anthropogenic organic complexants (citrate, EDTA and DTPA from 0.005 to 0.1 M) on the solubility of nickel(II), thorium(IV) and uranium (U(IV) and U(VI)) has been studied. Experiments were carried out in 95%-saturated Ca(OH){sub 2} solutions, representing the high pH conditions anticipated in the near field of a cementitious intermediate level radioactive waste repository. Results showed that Ni(II) solubility increased by 2–4 orders of magnitude in the presence of EDTA and DTPA and from 3 to 4 orders of magnitude in the case of citrate. Citrate had the greatest effect on the solubility of Th(IV) and U(IV)/(VI). XRD and SEM analyses indicate that the precipitates are largely amorphous; only in the case of Ni(II), is there some evidence of incipient crystallinity, in the form of Ni(OH){sub 2} (theophrastite). A study of the effect of calcium suggests that U(VI) and Ni(II) may form metal-citrate-OH complexes stabilised by Ca{sup 2+}. Thermodynamic modelling underestimates the concentrations in solution in the presence of the ligands for all the elements considered here. Further investigation of the behaviour of organic ligands under hyperalkaline conditions is important because of the use of the thermodynamic constants in preparing the safety case for the geological disposal of radioactive wastes.

  9. Inverse m-matrices and ultrametric matrices

    CERN Document Server

    Dellacherie, Claude; San Martin, Jaime

    2014-01-01

    The study of M-matrices, their inverses and discrete potential theory is now a well-established part of linear algebra and the theory of Markov chains. The main focus of this monograph is the so-called inverse M-matrix problem, which asks for a characterization of nonnegative matrices whose inverses are M-matrices. We present an answer in terms of discrete potential theory based on the Choquet-Deny Theorem. A distinguished subclass of inverse M-matrices is ultrametric matrices, which are important in applications such as taxonomy. Ultrametricity is revealed to be a relevant concept in linear algebra and discrete potential theory because of its relation with trees in graph theory and mean expected value matrices in probability theory. Remarkable properties of Hadamard functions and products for the class of inverse M-matrices are developed and probabilistic insights are provided throughout the monograph.

  10. Case study of water-soluble metal containing organic constituents of biomass burning aerosol

    Science.gov (United States)

    Alexandra L. Chang-Graham; Luisa T. M. Profeta; Timothy J. Johnson; Robert J. Yokelson; Alexander Laskin; Julia Laskin

    2011-01-01

    Natural and prescribed biomass fires are a major source of aerosols that may persist in the atmosphere for several weeks. Biomass burning aerosols (BBA) can be associated with long-range transport of water-soluble N-, S-, P-, and metal-containing species. In this study, BBA samples were collected using a particle-into-liquid sampler (PILS) from laboratory burns of...

  11. Solubility and crystal nucleation in organic solvents of two polymorphs of curcumin.

    Science.gov (United States)

    Liu, Jin; Svärd, Michael; Hippen, Perschia; Rasmuson, Åke C

    2015-07-01

    Two crystal polymorphs of 1,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (curcumin) have been obtained by crystallization from ethanol (EtOH) solution. The polymorphs have been characterized by differential scanning calorimetry, infrared spectroscopy, and X-ray powder diffraction and shown to be the previously described forms I and III. The solubility of both polymorphs in EtOH and of one polymorph in ethyl acetate (EA) has been measured between 10°C and 50°C with a gravimetric method. Primary nucleation of curcumin from EtOH solution has been investigated in 520 constant temperature crystallization experiments in sealed, magnetically stirred vials under different conditions of supersaturation, temperature, and agitation rate. By a thermodynamic analysis of the melting data and solubility of form I, the solid-state activity is estimated from 10°C up to the melting point. The solubility is lower in EtOH than in EA, and in both solvents, a positive deviation from Raoult's law is observed. Form I has lower solubility than form III and is accordingly thermodynamically more stable over the investigated temperature interval. Extrapolation of solubility regression models indicates that there should be a low-temperature enantiotropic transition point, below which form I will be metastable. By slurry conversion experiments, it is established that this temperature is below -30°C. All nucleation experiments resulted in the stable form I. The induction time is observed to decrease with increasing agitation rate up to a certain point, and then increase with further increasing agitation rate; a trend previously observed for other compounds. By correlating the induction time data obtained at different supersaturation and temperature, the interfacial energy of form I in EtOH is estimated to be 3.0 mJ/m(2) . © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Determination of the solubility of low volatility liquid organic compounds in water using volatile-tracer assisted headspace gas chromatography.

    Science.gov (United States)

    Zhang, Shu-Xin; Chai, Xin-Sheng; Barnes, Donald G

    2016-02-26

    This study reports a new headspace gas chromatographic method (HS-GC) for the determination of water solubility of low volatility liquid organic compounds (LVLOs). The HS-GC analysis was performed on a set of aqueous solutions containing a range of concentrations of toluene-spiked (as a tracer) LVLOs, from under-saturation to over-saturation. A plot of the toluene tracer GC signal vs. the concentration of the LVLO results in two lines of different slopes that intersect at the concentration corresponding to the compound's solubility in water. The results showed that the HS-GC method has good precision (RSD waters of environmental and biological systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Lectures on matrices

    CERN Document Server

    M Wedderburn, J H

    1934-01-01

    It is the organization and presentation of the material, however, which make the peculiar appeal of the book. This is no mere compendium of results-the subject has been completely reworked and the proofs recast with the skill and elegance which come only from years of devotion. -Bulletin of the American Mathematical Society The very clear and simple presentation gives the reader easy access to the more difficult parts of the theory. -Jahrbuch über die Fortschritte der Mathematik In 1937, the theory of matrices was seventy-five years old. However, many results had only recently evolved from sp

  14. Organic pollutant levels in an agricultural watershed: the importance of analyzing multiple matrices for assessing stream water pollution.

    Science.gov (United States)

    Gonzalez, Mariana; Miglioranza, Karina S B; Grondona, Sebastían I; Silva Barni, Maria Florencia; Martinez, Daniel E; Peña, Aránzazu

    2013-04-01

    This study is aimed at analyzing the occurrence and transport of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the Quequén Grande river basin, as representative of a catchment under diffuse pollution sources. Pollutant levels in soils, river bottom sediments (RBS), streamwater (Sw), suspended particle materials (SPMs), macrophytes and muscle of silverside were determined by GC-ECD. Soil K(d) values for the current-used insecticides, endosulfans and cypermethrin, were established. Total levels (ng g(-1) dry weight) in soil ranged between 0.07–0.9 for OCPs, 0.03–0.37 for PCBs and 0.01–0.05 for PBDEs. Endosulfan insecticide (α- + b- + sulfate metabolite) represented up to 72.5% of OCPs. The low soil retention for α-endosulfan (K(d): 77) and endosulfan sulfate (K(d): 100) allows their transport to Sw, SPM and RBS. Levels of endosulfan in Sw in some cases exceeded the value postulated by international guidelines for aquatic biota protection (3 ng L(-1)). PCB and PBDE pollution was related to harbour, dumping sites and pile tire burning. Tri and hexa PCB congeners predominated in all matrices and exceeded the quality guideline value of 0.04 ng L(-1) in Sw. Considering levels in silverside muscle, none of the oral reference doses were exceeded, however, PCBs accounted for 18.6% of the total daily allowed ingest for a 70 kg individual. Although the levels of PCBs and OCPs in soil and RBS were low and did not go beyond quality guidelines, these compounds could still represent a risk to aquatic biota and humanbeings, and thus actions towards preventing this situation should be undertaken.

  15. Evaluation of proline, chlorophyll, soluble sugar content and uptake of nutrients in the German chamomile (Matricaria chamomilla L. under drought stress and organic fertilizer treatments

    Directory of Open Access Journals (Sweden)

    Amin Salehi

    2016-10-01

    Conclusions: Totally, organic fertilization by vermicompost could partly alleviate the effect of drought stress on chamomile by increasing N, P and K uptake and leaf soluble sugar, especially in stressed treatments.

  16. pH-potentiometric determination of solubility of barely soluble organic extracting agents in water and aqueous solutions of neutral salts

    International Nuclear Information System (INIS)

    Pavlovskaya, E.M.; Charykov, A.K.; Tikhomirov, V.I.

    1977-01-01

    A pH-potentiometric method has been used to estimate the solubility of chloroform, benzene and nitrobenzene in water. The desalting effect is studied of alkali metal chlorides on chloroform solubility to establish the following phenomenological series of alkali metal cations by their desalting action: Li + + + + + . The non-conformity of chloroform solubility values in water-isoactive solutions of different salts is indicative of the high specificity of desalting processes with respect to the chemical nature of the desalting cation. Salt effects also essentially depend on the chemical nature of the desalted substance, particularly on its acid-base properties

  17. Dense tissue-like collagen matrices formed in cell-free conditions.

    Science.gov (United States)

    Mosser, Gervaise; Anglo, Anny; Helary, Christophe; Bouligand, Yves; Giraud-Guille, Marie-Madeleine

    2006-01-01

    A new protocol was developed to produce dense organized collagen matrices hierarchically ordered on a large scale. It consists of a two stage process: (1) the organization of a collagen solution and (2) the stabilization of the organizations by a sol-gel transition that leads to the formation of collagen fibrils. This new protocol relies on the continuous injection of an acid-soluble collagen solution into glass microchambers. It leads to extended concentration gradients of collagen, ranging from 5 to 1000 mg/ml. The self-organization of collagen solutions into a wide array of spatial organizations was investigated. The final matrices obtained by this procedure varied in concentration, structure and density. Changes in the liquid state of the samples were followed by polarized light microscopy, and the final stabilized gel states obtained after fibrillogenesis were analyzed by both light and electron microscopy. Typical organizations extended homogeneously by up to three centimetres in one direction and several hundreds of micrometers in other directions. Fibrillogenesis of collagen solutions of high and low concentrations led to fibrils spatially arranged as has been described in bone and derm, respectively. Moreover, a relationship was revealed between the collagen concentration and the aggregation of and rotational angles between lateral fibrils. These results constitute a strong base from which to further develop highly enriched collagen matrices that could lead to substitutes that mimic connective tissues. The matrices thus obtained may also be good candidates for the study of the three-dimensional migration of cells.

  18. Hygroscopic growth of water soluble organic carbon isolated from atmospheric aerosol collected at US national parks and Storm Peak Laboratory

    Science.gov (United States)

    Taylor, Nathan F.; Collins, Don R.; Lowenthal, Douglas H.; McCubbin, Ian B.; Gannet Hallar, A.; Samburova, Vera; Zielinska, Barbara; Kumar, Naresh; Mazzoleni, Lynn R.

    2017-02-01

    Due to the atmospheric abundance and chemical complexity of water soluble organic carbon (WSOC), its contribution to the hydration behavior of atmospheric aerosol is both significant and difficult to assess. For the present study, the hygroscopicity and CCN activity of isolated atmospheric WSOC particulate matter was measured without the compounding effects of common, soluble inorganic aerosol constituents. WSOC was extracted with high purity water from daily high-volume PM2.5 filter samples and separated from water soluble inorganic constituents using solid-phase extraction. The WSOC filter extracts were concentrated and combined to provide sufficient mass for continuous generation of the WSOC-only aerosol over the combined measurement time of the tandem differential mobility analyzer and coupled scanning mobility particle sizer-CCN counter used for the analysis. Aerosol samples were taken at Great Smoky Mountains National Park during the summer of 2006 and fall-winter of 2007-2008; Mount Rainier National Park during the summer of 2009; Storm Peak Laboratory (SPL) near Steamboat Springs, Colorado, during the summer of 2010; and Acadia National Park during the summer of 2011. Across all sampling locations and seasons, the hygroscopic growth of WSOC samples at 90 % RH, expressed in terms of the hygroscopicity parameter, κ, ranged from 0.05 to 0.15. Comparisons between the hygroscopicity of WSOC and that of samples containing all soluble materials extracted from the filters implied a significant modification of the hydration behavior of inorganic components, including decreased hysteresis separating efflorescence and deliquescence and enhanced water uptake between 30 and 70 % RH.

  19. Improved spectrophotometric analysis of fullerenes C60 and C70 in high-solubility organic solvents.

    Science.gov (United States)

    Törpe, Alexander; Belton, Daniel J

    2015-01-01

    Fullerenes are among a number of recently discovered carbon allotropes that exhibit unique and versatile properties. The analysis of these materials is of great importance and interest. We present previously unreported spectroscopic data for C60 and C70 fullerenes in high-solubility solvents, including error bounds, so as to allow reliable colorimetric analysis of these materials. The Beer-Lambert-Bouguer law is found to be valid at all wavelengths. The measured data were highly reproducible, and yielded high-precision molar absorbance coefficients for C60 and C70 in o-xylene and o-dichlorobenzene, which both exhibit a high solubility for these fullerenes, and offer the prospect of improved extraction efficiency. A photometric method for a C60/C70 mixture analysis was validated with standard mixtures, and subsequently improved for real samples by correcting for light scattering, using a power-law fit. The method was successfully applied to the analysis of C60/C70 mixtures extracted from fullerene soot.

  20. Linear and nonlinear methods in modeling the aqueous solubility of organic compounds.

    Science.gov (United States)

    Catana, Cornel; Gao, Hua; Orrenius, Christian; Stouten, Pieter F W

    2005-01-01

    Solubility data for 930 diverse compounds have been analyzed using linear Partial Least Square (PLS) and nonlinear PLS methods, Continuum Regression (CR), and Neural Networks (NN). 1D and 2D descriptors from MOE package in combination with E-state or ISIS keys have been used. The best model was obtained using linear PLS for a combination between 22 MOE descriptors and 65 ISIS keys. It has a correlation coefficient (r2) of 0.935 and a root-mean-square error (RMSE) of 0.468 log molar solubility (log S(w)). The model validated on a test set of 177 compounds not included in the training set has r2 0.911 and RMSE 0.475 log S(w). The descriptors were ranked according to their importance, and at the top of the list have been found the 22 MOE descriptors. The CR model produced results as good as PLS, and because of the way in which cross-validation has been done it is expected to be a valuable tool in prediction besides PLS model. The statistics obtained using nonlinear methods did not surpass those got with linear ones. The good statistic obtained for linear PLS and CR recommends these models to be used in prediction when it is difficult or impossible to make experimental measurements, for virtual screening, combinatorial library design, and efficient leads optimization.

  1. Photo and thermochemical evolution of astrophysical ice analogues as a source for soluble and insoluble organic materials in Solar system minor bodies

    Science.gov (United States)

    de Marcellus, Pierre; Fresneau, Aurelien; Brunetto, Rosario; Danger, Gregoire; Duvernay, Fabrice; Meinert, Cornelia; Meierhenrich, Uwe J.; Borondics, Ferenc; Chiavassa, Thierry; Le Sergeant d'Hendecourt, Louis

    2017-01-01

    Soluble and insoluble organic matter (IOM) is a key feature of primitive carbonaceous chondrites. We observe the formation of organic materials in the photothermochemical treatment of astrophysical ices in the laboratory. Starting from a low vacuum ultraviolet (VUV) irradiation dose on templates of astrophysical ices at 77 K, we obtain first a totally soluble form of organic matter at room temperature. Once this organic residue is formed, irradiating it further in vacuum results in the production of a thin altered dark crust on top of the initial soluble one. The whole residue is studied here by non-destructive methods inducing no alteration of samples, visible microscopy and mid-infrared (micro-)spectroscopy. After water extraction of the soluble part, an insoluble fraction remains on the sample holder which provides a largely different infrared spectrum when compared to the one of the soluble sample. Therefore, from the same VUV and thermal processing of initial simple ices, we produce first a soluble material from which a much larger irradiation dose leads to an insoluble one. Interestingly, this insoluble fraction shows some spectral similarities with natural samples of IOM extracted from two meteorites (Tagish Lake and Murchison), selected as examples of primitive materials. It suggests that the organic molecular diversity observed in meteorites may partly originate from the photo and thermal processing of interstellar/circum-stellar ices at the final stages of molecular cloud evolution towards the build-up of our Solar system.

  2. Exploratory Project: Rigid nanostructured organic polymer monolith for in situ collection and analysis of plant metabolites from soil matrices

    Energy Technology Data Exchange (ETDEWEB)

    Tharayil, Nishanth [Clemson Univ., SC (United States)

    2016-06-29

    Plant metabolites released from litter leachates and root exudates enable plants to adapt and survive in a wide range of habitats by facilitating resource foraging and plant-organismal interactions, and could influence soil carbon storage. The biological functions of these plant inputs and the organismal interactions they facilitate in soil are strictly governed by their composition and molecular identity. Our current understanding about the molecular identity of exudates is based on physiological studies that are done in soil-less axenic cultures. On the other hand, ecological studies that rely on isotope labeling to track the fluxes of carbon from plants to soil have found the complexities of soil-microbe matrices as an insurmountable barrier to undertake any meaningful molecular level characterization of plant inputs. Although it is constantly advocated to undertake a molecular level identification of the dynamicity of plant metabolites in soils, the complexity of soil system has thus far prevented any such endeavors. We developed polymeric probes through in-situ polymerization of poly(styrene-co-vinylbenzyl chloride-co-divinylbenzene) to elucidate the chemical environment of the soil to which the plant roots are exposed. Hypercrosslinking of the polymeric probes through an in-situ Friedel-Crafts alkylation significantly increased the surface area and the sorption capacity of the probes. Surface functionalization of the probes using a hybrid approach was also attempted. The efficacy of these probes was tested using batch equilibration. Scanning electron microscopy revealed extensive modification of the surface of the probes through hypercrosslinking. The probes exhibited a lower site specific sorption (slope of Freundlich adsorption isotherm close to unity) and percent recovery of the sorbed compounds from the probes were >70, indicating a predominance of reversible sorption. Further we imparted specificity to this copolymer matrix by using molecular

  3. Vaginal Fibroblastic Cells from Women with Pelvic Organ Prolapse Produce Matrices with Increased Stiffness and Collagen Content

    NARCIS (Netherlands)

    Ruiz-Zapata, A.M.Kerkhof, M.H.; Ghazanfari, S.; Zandieh-Doulabi, B.; Stoop, R.; Smit, T.H.; Helder, M.N.

    2016-01-01

    Pelvic organ prolapse (POP) is characterised by the weakening of the pelvic floor support tissues, and often by subsequent prolapse of the bladder outside the body, i.e. cystocele. The bladder is kept in place by the anterior vaginal wall which consists of a dense extracellular matrix rich in

  4. Bis[(lprolinate-N,O]Zn: A water-soluble and recycle catalyst for various organic transformations

    Directory of Open Access Journals (Sweden)

    Roona Poddar

    2017-05-01

    Full Text Available Under the green chemistry perspective, bis[(lprolinate-N,O]Zn (also called zinc–proline or Zn[(l-pro]2 has proven its competence as a promising alternative in a plethora of applications such as catalyst or promoter. Owing to its biodegradable and non-toxic nature of bis[(lprolinate-N,O]Zn, it is being actively investigated as a water soluble green catalyst for synthetic chemistry. Bis[(lprolinate-N,O]Zn are readily utilized under mild conditions and have high selectivity and reactivity with broad range of substrate acceptance to make it better reaction medium for a wide variety of organic transformations. This Review summarizes the till date literature on its synthesis, characterization, and its catalytic role in various organic reactions.

  5. Introduction into Hierarchical Matrices

    KAUST Repository

    Litvinenko, Alexander

    2013-12-05

    Hierarchical matrices allow us to reduce computational storage and cost from cubic to almost linear. This technique can be applied for solving PDEs, integral equations, matrix equations and approximation of large covariance and precision matrices.

  6. Introduction into Hierarchical Matrices

    KAUST Repository

    Litvinenko, Alexander

    2013-01-01

    Hierarchical matrices allow us to reduce computational storage and cost from cubic to almost linear. This technique can be applied for solving PDEs, integral equations, matrix equations and approximation of large covariance and precision matrices.

  7. Characterization of water-soluble organic aerosol in coastal New England: Implications of variations in size distribution

    Science.gov (United States)

    Ziemba, L. D.; Griffin, R. J.; Whitlow, S.; Talbot, R. W.

    2011-12-01

    Size distributions up to 10-micron aerosol diameter ( DP) of organic carbon (OC) and water-soluble organic carbon (WSOC) were measured at two sites in coastal New England, slightly inland at Thompson Farm (TF) and offshore at Isles of Shoals (IOS). Significant OC concentrations were measured across the full size distribution at TF and IOS, respectively. The WSOC fraction (WSOC/OC) was largest in the accumulation mode with values of 0.86 and 0.93 and smallest in the coarse mode with values of 0.61 and 0.79 at TF and IOS, respectively. Dicarboxylic acids containing up to five carbon atoms (C 5) were concentrated in droplet and accumulation mode aerosol with only minor contributions in the coarse mode. C 1-C 3 monocarboxylic acids were generally near or below detection limits. Results from proton nuclear magnetic resonance (H +-NMR) spectroscopy analyses showed that the organic functional group characterized by protons in the alpha position to an unsaturated carbon atoms ([H-C-C dbnd ]) was the dominant WSOC functionality at both TF and IOS, constituting 34 and 43% of carbon-weighted H +-NMR signal, respectively. Size distributions of each H +-NMR-resolved organic functionality are presented. Source apportionment using H +-NMR fingerprints is also presented, and results indicate that nearly all of the WSOC at TF and IOS spectroscopically resembled secondary organic aerosol, regardless of DP.

  8. Hygroscopic properties of internally mixed particles composed of NaCl and water-soluble organic acids.

    Science.gov (United States)

    Ghorai, Suman; Wang, Bingbing; Tivanski, Alexei; Laskin, Alexander

    2014-02-18

    Atmospheric aging of naturally emitted marine aerosol often leads to formation of internally mixed particles composed of sea salts and water-soluble organic compounds of anthropogenic origin. Mixing of sea salt and organic components has profound effects on the evolving chemical composition and hygroscopic properties of the resulted particles, which are poorly understood. Here, we have studied chemical composition and hygroscopic properties of laboratory generated NaCl particles mixed with malonic acid (MA) and glutaric acid (GA) at different molar ratios using micro-FTIR spectroscopy, atomic force microscopy, and X-ray elemental microanalysis. Hygroscopic properties of internally mixed NaCl and organic acid particles were distinctly different from pure components and varied significantly with the type and amount of organic compound present. Experimental results were in a good agreement with the AIM modeling calculations of gas/liquid/solid partitioning in studied systems. X-ray elemental microanalysis of particles showed that Cl/Na ratio decreased with increasing organic acid component in the particles with MA yielding lower ratios relative to GA. We attribute the depletion of chloride to the formation of sodium malonate and sodium glutarate salts resulted by HCl evaporation from dehydrating particles.

  9. Water-soluble Organic Components in Aerosols Associated with Savanna Fires in Southern Africa: Identification, Evolution and Distribution

    Science.gov (United States)

    Gao, Song; Hegg, Dean A.; Hobbs, Peter V.; Kirchstetter, Thomas W.; Magi, Brian I.; Sadilek, Martin

    2003-01-01

    During the SAFARI 2000 field campaign, both smoke aerosols from savanna fires and haze aerosols in the boundary layer and in the free troposphere were collected from an aircraft in southern Africa. These aerosol samples were analyzed for their water-soluble chemical components, particularly the organic species. A novel technique, electrospray ionization-ion trap mass spectrometry, was used concurrently with an ion chromatography system to analyze for carbohydrate species. Seven carbohydrates, seven organic acids, five metallic elements, and three inorganic anions were identified and quantified. On the average, these 22 species comprised 36% and 27% of the total aerosol mass in haze and smoke aerosols, respectively. For the smoke aerosols, levoglucosan was the most abundant carbohydrate species, while gluconic acid was tentatively identified as the most abundant organic acid. The mass abundance and possible source of each class of identified species are discussed, along with their possible formation pathways. The combustion phase of a fire had an impact on the chemical composition of the emitted aerosols. Secondary formation of sulfate, nitrate, levoglucosan, and several organic acids occurred during the initial aging of smoke aerosols. It is likely that under certain conditions, some carbohydrate species in smoke aerosols, such as levoglucosan, were converted to organic acids during upward transport.

  10. Atmospheric water-soluble organic nitrogen (WSON) in the eastern Mediterranean: origin and ramifications regarding marine productivity

    Science.gov (United States)

    Nehir, Münevver; Koçak, Mustafa

    2018-03-01

    Aerosol and rain sampling in two size fractions was carried out at a rural site located on the coast of the eastern Mediterranean, Erdemli, Turkey (36°33'54'' N, 34°15'18'' E). A total of 674 aerosol samples in two size fractions (337 coarse, 337 fine) and 23 rain samples were collected between March 2014 and April 2015. Samples were analyzed for NO3-, NH4+ and ancillary water-soluble ions using ion chromatography and water-soluble total nitrogen (WSTN) by applying a high-temperature combustion method. The mean aerosol water-soluble organic nitrogen (WSON) was 23.8 ± 16.3 nmol N m-3, reaching a maximum of 79 nmol N m-3, with about 66 % being associated with coarse particles. The volume weighted mean (VWM) concentration of WSON in rain was 21.5 µmol N L-1. The WSON contributed 37 and 29 % to the WSTN in aerosol and rainwater, respectively. Aerosol WSON concentrations exhibited large temporal variation, mainly due to meteorology and the origin of air mass flow. The highest mean aerosol WSON concentration was observed in the summer and was attributed to the absence of rain and resuspension of cultivated soil in the region. The mean concentration of WSON during dust events (38.2 ± 17.5 nmol N m-3) was 1.3 times higher than that of non-dust events (29.4 ± 13.9 nmol N m-3). Source apportionment analysis demonstrated that WSON was originated from agricultural activities (43 %), secondary aerosol (20 %), nitrate (22 %), crustal material (10 %) and sea salt (5 %). The dry and wet depositions of WSON were equivalent and amounted to 36 % of the total atmospheric WSTN flux.

  11. Extending the analytical window for water-soluble organic matter in sediments by aqueous Soxhlet extraction

    Science.gov (United States)

    Schmidt, Frauke; Koch, Boris P.; Witt, Matthias; Hinrichs, Kai-Uwe

    2014-09-01

    Dissolved organic matter (DOM) in marine sediments is a complex mixture of thousands of individual constituents that participate in biogeochemical reactions and serve as substrates for benthic microbes. Knowledge of the molecular composition of DOM is a prerequisite for a comprehensive understanding of the biogeochemical processes in sediments. In this study, interstitial water DOM was extracted with Rhizon samplers from a sediment core from the Black Sea and compared to the corresponding water-extractable organic matter fraction (Soxhlet extraction, which mobilizes labile particulate organic matter and DOM. After solid phase extraction (SPE) of DOM, samples were analyzed for the molecular composition by Fourier Transform Ion-Cyclotron Resonance Mass Spectrometry (FT-ICR MS) with electrospray ionization in negative ion mode. The average SPE extraction yield of the dissolved organic carbon (DOC) in interstitial water was 63%, whereas less than 30% of the DOC in Soxhlet-extracted organic matter was recovered. Nevertheless, Soxhlet extraction yielded up to 4.35% of the total sedimentary organic carbon, which is more than 30-times the organic carbon content of the interstitial water. While interstitial water DOM consisted primarily of carbon-, hydrogen- and oxygen-bearing compounds, Soxhlet extracts yielded more complex FT-ICR mass spectra with more peaks and higher abundances of nitrogen- and sulfur-bearing compounds. The molecular composition of both sample types was affected by the geochemical conditions in the sediment; elevated concentrations of HS- promoted the early diagenetic sulfurization of organic matter. The Soxhlet extracts from shallow sediment contained specific three- and four-nitrogen-bearing molecular formulas that were also detected in bacterial cell extracts and presumably represent proteinaceous molecules. These compounds decreased with increasing sediment depth while one- and two-nitrogen-bearing molecules increased, resulting in a higher

  12. Water Soluble Organic Nitrogen (WSON) in Ambient Fine Particles Over a Megacity in South China: Spatiotemporal Variations and Source Apportionment

    Science.gov (United States)

    Yu, Xu; Yu, Qingqing; Zhu, Ming; Tang, Mingjin; Li, Sheng; Yang, Weiqiang; Zhang, Yanli; Deng, Wei; Li, Guanghui; Yu, Yuegang; Huang, Zhonghui; Song, Wei; Ding, Xiang; Hu, Qihou; Li, Jun; Bi, Xinhui; Wang, Xinming

    2017-12-01

    Organic nitrogen aerosols are complex mixtures and important compositions in ambient fine particulate matters (PM2.5), yet their sources and spatiotemporal patterns are not well understood particularly in regions influenced by intensive human activities. In this study, filter-based ambient PM2.5 samples at four stations (one urban, two rural, plus one urban roadside) and PM samples from combustion sources (vehicle exhaust, ship emission, and biomass burning) were collected in the coastal megacity Guangzhou, south China, for determining water soluble organic nitrogen (WSON) along with other organic and inorganic species. The annual average WSON concentrations, as well as the ratios of WSON to water soluble total nitrogen, were all significantly higher at rural sites than urban sites. Average WSON concentrations at the four sites during the wet season were quite near each other, ranging from 0.41 to 0.49 μg/m3; however, they became 2 times higher at the rural sites than at the urban sites during the dry season. Five major sources for WSON were identified through positive matrix factorization analysis. Vehicle emission (29.3%), biomass burning (22.8%), and secondary formation (20.2%) were three dominant sources of WSON at the urban station, while vehicle emission (45.4%) and dust (28.6%) were two dominant sources at the urban roadside station. At the two rural sites biomass burning (51.1% and 34.1%, respectively) and secondary formation (17.8% and 30.5%, respectively) were dominant sources of WSON. Ship emission contributed 8-12% of WSON at the four sites. Natural vegetation seemed to have very minor contribution to WSON.

  13. Effect of atmospheric organic complexation on iron-bearing dust solubility

    OpenAIRE

    Paris , R.; Desboeufs , K. V.

    2013-01-01

    International audience; Recent studies reported that the effect of organic complexation may be a potentially important process to be considered by models estimating atmospheric iron flux to the ocean. In this study, we investigated this process effect by a series of dissolution experiments on iron-bearing dust in the presence or the absence of various organic compounds (acetate, formate, oxalate, malonate, succinate, glutarate, glycolate, lactate, tartrate and humic acid as an analogue of hum...

  14. Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems

    Energy Technology Data Exchange (ETDEWEB)

    Pluth, Michael D.; Raymond, Kenneth N.; Bergman, Robert G.

    2008-02-16

    Inspired by the efficiency and selectivity of enzymes, synthetic chemists have designed and prepared a wide range of host molecules that can bind smaller molecules with their cavities; this area has become known as 'supramolecular' or 'host-guest' chemistry. Pioneered by Lehn, Cram, Pedersen, and Breslow, and followed up by a large number of more recent investigators, it has been found that the chemical environment in each assembly - defined by the size, shape, charge, and functional group availability - greatly influences the guest-binding characteristics of these compounds. In contrast to the large number of binding studies that have been carried out in this area, the exploration of chemistry - especially catalytic chemistry - that can take place inside supramolecular host cavities is still in its infancy. For example, until the work described here was carried out, very few examples of organometallic reactivity inside supramolecular hosts were known, especially in water solution. For that reason, our group and the group directed by Kenneth Raymond decided to take advantage of our complementary expertise and attempt to carry out metal-mediated C-H bond activation reactions in water-soluble supramolecular systems. This article begins by providing background from the Raymond group in supramolecular coordination chemistry and the Bergman group in C-H bond activation. It goes on to report the results of our combined efforts in supramolecular C-H activation reactions, followed by extensions of this work into a wider range of intracavity transformations.

  15. Linear solvation energy relationships: 36. Molecular properties governing solubilities of organic nonelectrolytes in water.

    Science.gov (United States)

    Kamlet, M J; Doherty, R M; Abboud, J L; Abraham, M H; Taft, R W

    1986-04-01

    Molar solubilities of non-hydrogen bond donor and weak hydrogen bond donor liquid aliphatic solutes in water, or the nearly equivalent quantities, Sg/Kgw, where Kgw is the gas-water partition coefficient and Sg is the solute concentration in the solute saturated vapor (Sg = Patm/24.5) are well correlated by the equation: log Sw congruent to log (Sg/Kgw) = 0.54 - 3.32V/100 + 0.46 pi* + 5.17 (beta or beta m) (at 25 degrees C) n = 105, r = 0.9954, SD = 0.137 V is the solute molar volume (the molecular weight divided by the liquid density at 20 degrees C), and pi* and beta are the solvatochromic parameters that are measures of solute dipolarity-polarizability and hydrogen bond acceptor basicity. The equation, which applies to liquid monofunctional aliphatic solutes is used to calculate additional new beta and beta m values. The beta m values, which are intended to apply to self-associated compounds when acting as "monomer" solutes, are: methanol, 0.42; all primary alkanols, 0.45; all secondary alkanols, 0.51; and all tertiary alkanols, 0.57.

  16. Case study of water-soluble metal containing organic constituents of biomass burning aerosol.

    Science.gov (United States)

    Chang-Graham, Alexandra L; Profeta, Luisa T M; Johnson, Timothy J; Yokelson, Robert J; Laskin, Alexander; Laskin, Julia

    2011-02-15

    Natural and prescribed biomass fires are a major source of aerosols that may persist in the atmosphere for several weeks. Biomass burning aerosols (BBA) can be associated with long-range transport of water-soluble N-, S-, P-, and metal-containing species. In this study, BBA samples were collected using a particle-into-liquid sampler (PILS) from laboratory burns of vegetation collected on military bases in the southeastern and southwestern United States. The samples were then analyzed using high resolution electrospray ionization mass spectrometry (ESI/HR-MS) that enabled accurate mass measurements for hundreds of species with m/z values between 70 and 1000 and assignment of elemental formulas. Mg, Al, Ca, Cr, Mn, Fe, Ni, Cu, Zn, and Ba-containing organometallic species were identified. The results suggest that the biomass may have accumulated metal-containing species that were re-emitted during biomass burning. Further research into the sources, dispersion, and persistence of metal-containing aerosols, as well as their environmental effects, is needed.

  17. Impact of tree cutting on water-soluble organic compounds in podzolic soils of the European North-East

    Science.gov (United States)

    Lapteva, Elena; Bondarenko, Natalia; Shamrikova, Elena; Kubik, Olesya; Punegov, Vasili

    2016-04-01

    Water-soluble organic compounds (WOCs) and their single components, i.e. low-molecular organic acids, alcohols, and carbohydrates, attain a great deal of attention among soil scientists. WOCs are an important component of soil organic matter (SOM) and form as a results of different biological and chemical processes in soils. These processes are mainly responsible for formation and development of soils in aboveground ecosystems. The purpose of the work was identifying qualitative and quantitative composition of low-molecular organic substances which form in podzolic loamy soils against natural reforestation after spruce forest cutting. The studies were conducted on the territory of the European North-East of Russia, in the middle taiga subzone (Komi Republic, Ust-Kulom region). The study materials were soil of undisturbed bilberry spruce forest (Sample Plot 1 (SP1)) and soils of different-aged tree stands where cutting activities took place in winter 2001/2002 (SP2) and 1969/1970 (SP3). Description of soils and vegetation cover on the plots is given in [1]. Low-molecular organic compounds in soil water extracts were identified by the method of gas chromatography mass-spectrometry [2, 3]. Finally, reforestationafterspruceforestcutting was found to be accompanied by different changes in soil chemical composition. In contrast with soils under undisturbed spruce forest, organic soil horizons under different-aged cuts decreased in organic carbon reserves and production of low-molecular organic compounds, changed in soil acidity. Within the soil series of SP1→SP2→SP3, the highest content of WOCs was identified for undisturbed spruce forest (738 mg kg-1 soil). In soils of coniferous-deciduous forests on SP1 and SP3, WOC content was 294 and 441 mg kg-1 soil, correspondingly. Soils at cuts decreased in concentration of any water-soluble low-molecular SOM components as low-molecular acids, alcohols, and carbohydrates. Structure of low-molecular WOCs in the study podzolic

  18. Extractability of water-soluble soil organic matter as monitored by spectroscopic and chromatographic analyses.

    Science.gov (United States)

    Nkhili, Ezzhora; Guyot, Ghislain; Vassal, Nathalie; Richard, Claire

    2012-07-01

    Cold and hot water processes have been intensively used to recover soil organic matter, but the effect of extraction conditions on the composition of the extracts were not well investigated. Our objective was to optimize the extraction conditions (time and temperature) to increase the extracted carbon efficiency while minimizing the possible alteration of water extractable organic matter of soil (WEOM). WEOM were extracted at 20°C, 60°C, or 80°C for 24 h, 10-60 min, and 20 min, respectively. The different processes were compared in terms of pH of suspensions, yield of organic carbon, spectroscopic properties (ultraviolet-visible absorption and fluorescence), and by chromatographic analyses. For extraction at 60°C, the time 30 min was optimal in terms of yield of organic carbon extracted and concentration of absorbing and fluorescent species. The comparison of WEOM 20°C, 24 h; 60°C, 30 min; and 80°C, 20 min highlighted significant differences. The content of total organic carbon, the value of specific ultraviolet absorbance (SUVA(254)), the absorbance ratio at 254 and 365 nm (E (2)/E (3)), and the humification index varied in the order: WEOM (20°C, 24 h) < WEOM (80°C, 20 min) < WEOM (60°C, 30 min). The three WEOM contained common fluorophores associated with simple aromatic structures and/or fulvic-like and common peaks of distinct polarity as detected by ultra performance liquid chromatography. For the soil chosen, extraction at 60°C for 30 min is the best procedure for enrichment in organic chemicals and minimal alteration of the organic matter.

  19. Investigation of water-soluble organic matter extracted from shales during leaching experiments

    Science.gov (United States)

    Zhu, Yaling; Vieth-Hillebrand, Andrea; Wilke, Franziska D. H.; Horsfield, Brian

    2017-04-01

    The huge volumes and unknown composition of flowback and produced waters cause major public concerns about the environmental and social compatibility of hydraulic fracturing and the exploitation of gas from unconventional reservoirs. Flowback and produced waters contain not only residues of fracking additives but also chemical species that are dissolved from the shales themselves during fluid-rock interaction. Knowledge of the composition, size and structure of dissolved organic carbon (DOC) as well as the main controls on the release of DOC are a prerequisite for a better understanding of these interactions and its effects on composition of flowback and produced water. Black shales from four different geological settings and covering a maturity range Ro = 0.3-2.6% were extracted with deionized water. The DOC yields were found to decrease rapidly with increasing diagenesis and remain low throughout catagenesis. Four DOC fractions have been qualitatively and quantitatively characterized using size-exclusion chromatography. The concentrations of individual low molecular weight organic acids (LMWOA) decrease with increasing maturity of the samples except for acetate extracted from the overmature Posidonia shale, which was influenced by hydrothermal brines. The oxygen content of the shale organic matter also shows a significant influence on the release of organic acids, which is indicated by the positive trend between oxygen index (OI) and the concentrations of formate and acetate. Based on our experiments, both the properties of the organic matter source and the thermal maturation progress of the shale organic matter significantly influence the amount and quality of extracted organic compounds during the leaching experiments.

  20. Microanalysis of Organic Pigments in Ancient Textiles by Surface-Enhanced Raman Scattering on Agar Gel Matrices

    Directory of Open Access Journals (Sweden)

    Marilena Ricci

    2016-01-01

    Full Text Available We review some new methods based on surface-enhanced Raman scattering (SERS for the nondestructive/minimally invasive identification of organic colorants in objects whose value or function precludes sampling, such as historic and archeological textiles, paintings, and drawing. We discuss in detail the methodology we developed for the selective extraction and identification of anthraquinones and indigoids in the typical concentration used in textiles by means of an ecocompatible homogeneous nanostructured agar matrix. The extraction system was modulated according to the chemical properties of the target analyte by choosing appropriate reagents for the extraction and optimizing the extraction time. The system has been found to be extremely stable, easy to use and produce, easy to store, and at the same time able to be analyzed even after long time intervals, maintaining its enhancement properties unaltered, without the detriment of the extracted compound. Highly structured SERS band intensities have been obtained from the extracted dyes adopting laser light excitations at 514.5 and 785 nm of a micro-Raman setup. This analytical method has been found to be extremely safe for the analyzed substrates, thus being a promising procedure for the selective analysis and detection of molecules at low concentration in the field of artworks conservation.

  1. The speciation, stability, solubility and biodegradation of organic co-contaminant radionuclide complexes: A review

    International Nuclear Information System (INIS)

    Keith-Roach, Miranda J.

    2008-01-01

    The potential migration of radionuclides is of concern at contaminated land sites and, in the long term, waste repositories. Pathways of migration need to be characterised on a predictive level so that management decisions can be made with confidence. A pathway that is relatively poorly understood at present is radionuclide solubilisation due to complexation by organic complexing agents that are present in mixed radioactive wastes, and at radioactively contaminated land sites. Interactions of the complexing agents with radionuclides and the host environment, and the response to changes in the physicochemical conditions make their role far from simple to elucidate. In addition, chemical and biodegradation of the organic materials may be important. In this paper, key co-contaminant organics are reviewed with emphasis on their environmental fate and impact on radionuclide migration

  2. The speciation, stability, solubility and biodegradation of organic co-contaminant radionuclide complexes: A review

    Energy Technology Data Exchange (ETDEWEB)

    Keith-Roach, Miranda J. [Biogeochemistry and Environmental Analytical Chemistry Group/Consolidated Radio-isotope Facility, School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: mkeith-roach@plymouth.ac.uk

    2008-06-15

    The potential migration of radionuclides is of concern at contaminated land sites and, in the long term, waste repositories. Pathways of migration need to be characterised on a predictive level so that management decisions can be made with confidence. A pathway that is relatively poorly understood at present is radionuclide solubilisation due to complexation by organic complexing agents that are present in mixed radioactive wastes, and at radioactively contaminated land sites. Interactions of the complexing agents with radionuclides and the host environment, and the response to changes in the physicochemical conditions make their role far from simple to elucidate. In addition, chemical and biodegradation of the organic materials may be important. In this paper, key co-contaminant organics are reviewed with emphasis on their environmental fate and impact on radionuclide migration.

  3. Multi-layer solid-phase extraction and evaporation-enrichment methods for polar organic chemicals from aqueous matrices.

    Science.gov (United States)

    Köke, Niklas; Zahn, Daniel; Knepper, Thomas P; Frömel, Tobias

    2018-03-01

    Analysis of polar organic chemicals in the aquatic environment is exacerbated by the lack of suitable and widely applicable enrichment methods. In this work, we assessed the suitability of a novel combination of well-known solid-phase extraction (SPE) materials in one cartridge as well as an evaporation method and for the enrichment of 26 polar model substances (predominantly log D evaporation method were investigated for the recovery and matrix effects of the model substances and analyzed with hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS). In total, 65% of the model substances were amenable (> 10% recovery) to the mlSPE method with a mean recovery of 76% while 73% of the model substances were enriched with the evaporation method achieving a mean recovery of 78%. Target and non-target screening comparison of both methods with a frequently used reversed-phase SPE method utilizing "hydrophilic and lipophilic balanced" (HLB) material was performed. Target analysis showed that the mlSPE and evaporation method have pronounced advantages over the HLB method since the HLB material retained only 30% of the model substances. Non-target screening of a ground water sample with the investigated enrichment methods showed that the median retention time of all detected features on a HILIC system decreased in the order mlSPE (3641 features, median t R 9.7 min), evaporation (1391, 9.3 min), HLB (4414, 7.2 min), indicating a higher potential of the described methods to enrich polar analytes from water compared with HLB-SPE. Graphical abstract Schematic of the method evaluation (recovery and matrix effects) and method comparison (target and non-target analysis) of the two investigated enrichment methods for very polar chemicals in aqueousmatrices.

  4. Advanced oxidation of water soluble organics (WSO) from near- and supercritical hydrothermal liquefaction (HTL) of biomass

    DEFF Research Database (Denmark)

    Arturi, Katarzyna Ratajczyk; Nielsen, Rudi Pankratz; Muff, Jens

    plant at Aalborg University, Denmark. The effectiveness of each process was evaluated concerning the organic content (TOC and COD) as well as the detailed composition of the samples (GCMS). Chosen process parameters were varied in the experiments (electric current - EO, concentration of H2O2 - FO...

  5. Solubility measurement and correlation of the form A of ibrutinib in organic solvents from 278.15 to 323.15 K

    International Nuclear Information System (INIS)

    Chen, Zhenzhen; Zhai, Jinghuan; Liu, Xijian; Mao, Shimin; Zhang, Lijuan; Rohani, Sohrab; Lu, Jie

    2016-01-01

    Highlights: • The solubility of ibrutinib (form A) in organic solvents was firstly reported. • Apelblat, λh, empirical polynomial equations were used to correlate the solubility. • The solubility order: MEK > acetone > EA > 1-butanol > acetonitrile ≈ IPA > MTBE. - Abstract: In this work, the solubility of the form A of ibrutinib in isopropanol (IPA), 1-butanol, ethyl acetate (EA), acetonitrile, acetone, methyl ethyl ketone (MEK) and methyl tertiary butyl ether (MTBE) was firstly experimentally determined by a gravimetric method in the temperature range from 278.15 to 323.15 K at atmospheric pressure. The experimental solubility data were correlated by several commonly used models including the modified Apelblat equation, the Buchowski-Ksiazczak λh equation and an empirical quartic polynomial equation. The results showed that, in the temperature range investigated, the solubility of ibrutinib generally increased with the increasing temperature, and the solubility order at the room temperature in the studied solvents was: MEK > acetone > ethyl acetate > 1-butanol > acetonitrile ≈ isopropanol > MTBE. In addition, all the models gave satisfactory correlation results, in which the empirical quartic polynomial equation stood out to be more suitable with a higher accuracy than the other two equations.

  6. Immunological monitoring after organ transplantation: potential role of soluble CD30 blood level measurement.

    Science.gov (United States)

    Truong, Dinh Quang; Darwish, Ahmed A; Gras, Jérémie; Wieërs, Grégoire; Cornet, Anne; Robert, Annie; Mourad, Michel; Malaise, Jacques; de Ville de Goyet, Jean; Reding, Raymond; Latinne, Dominique

    2007-06-01

    Analysing the relevance of soluble CD30 (sCD30) in the bloodstream before and after transplantation may be important for the monitoring of transplant recipients. In this study, 27 patients (15 pediatric liver and 12 adult kidney graft recipients) were investigated. In the liver graft group, the patients who developed acute rejection during the first month (n=9) had a slightly higher sCD30 value on pre-transplantation baseline (day 0) and post-transplantation day 7, when compared to patients with normal graft function (n=6) (day 0: 102(1.6) U/ml versus 118(1.5) U/ml, p=0.52) and (day 7: 69(1.5) U/ml versus 83(1.6) U/ml, p=0.47). Increased serum sCD30 was shown to correlate with increased interleukin-10 circulating levels between day 0 and day 7 (r=0.53; p=0.04), whereas, no correlation could be evidenced between interferon-gamma (IFN-gamma) and sCD30 (r=0.02; p=0.47). Similarly, in the kidney transplantation group, no significant difference was found in sCD30 levels at day 0 in both groups with graft rejection or normal graft function (n=6) (85(1.3) U/ml versus 77(1.6) U/ml, p=0.66), but sCD30 decreased significantly at day 7 post-transplantation from baseline value in the rejection group (n=6) (77(1.6) versus 35(1.4); p=0.02). We conclude that increased serum sCD30 was correlated with increased IL-10 (interleukin-10) circulating levels, but not with IFN-gamma levels in the post-transplantation period. Neither pre-transplantation sCD30 nor sCD30 at day 7 post-transplantation could be correlated with acute rejection in liver graft recipient. The monitoring of sCD30 might constitute a tool to assess the risk of acute rejection in renal transplant but did not appear as a valuable mean for early immunological monitoring in the small group of liver allograft recipients patients analysed in this study.

  7. Nonlinear Transport in Organic Thin Film Transistors with Soluble Small Molecule Semiconductor.

    Science.gov (United States)

    Kim, Hyeok; Song, Dong-Seok; Kwon, Jin-Hyuk; Jung, Ji-Hoon; Kim, Do-Kyung; Kim, SeonMin; Kang, In Man; Park, Jonghoo; Tae, Heung-Sik; Battaglini, Nicolas; Lang, Philippe; Horowitz, Gilles; Bae, Jin-Hyuk

    2016-03-01

    Nonlinear transport is intensively explained through Poole-Frenkel (PF) transport mechanism in organic thin film transistors with solution-processed small molecules, which is, 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene. We outline a detailed electrical study that identifies the source to drain field dependent mobility. Devices with diverse channel lengths enable the extensive exhibition of field dependent mobility due to thermal activation of carriers among traps.

  8. Behavior of soluble and immobilized acid phosphatase in hydro-organic media.

    Science.gov (United States)

    Wan, H; Horvath, C

    1975-11-20

    The hydrolysis of p-nitrophenyl phosphate by wheat germ acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) has been investigated in mixtures of aqueous buffers with acetone, dioxane and acetonitrile. The enzyme was either in free solution or immobilized on a pellicular support which consisted of a porous carbonaceous layer on solid glass beads. The highest enzyme activity was obtained in acetone and acetonitrile mixed with citrate buffer over a wide range of organic solvent concentration. In 50% (v/v) acetone both V and Km of the immobilized enzyme were about half of the values in the neat aqueous buffer, but the Ki for inorganic phosphate was unchanged. In 50% (v/v) mixtures of various solvents and citrate buffers of different pH, the enzymic activity was found to depend on the pH of the aqueous buffer component rather than the pH of the hydro-organic mixture as measured with the glass-calomel electrode. The relatively high rates of p-nitrophenol liberation in the presence of glucose even at high organic solvent concentrations suggest that transphosphorylation is facilitated at low water activity.

  9. Supercritical fluid extraction behaviour of polymer matrices

    International Nuclear Information System (INIS)

    Sujatha, K.; Kumar, R.; Sivaraman, N.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2007-01-01

    Organic compounds present in polymeric matrices such as neoprene, surgical gloves and PVC were co-extracted during the removal of uranium using supercritical fluid extraction (SFE) technique. Hence SFE studies of these matrices were carried out to establish the extracted species using HPLC, IR and mass spectrometry techniques. The initial study indicated that uranium present in the extract could be purified from the co-extracted organic species. (author)

  10. Solubility of Benzo[a]pyrene and Organic Matter of Soil in Subcritical Water

    Directory of Open Access Journals (Sweden)

    Svetlana Sushkova

    2015-12-01

    Full Text Available A dynamic subcritical water extraction method of benzo[a]pyrene from soils is under consideration. The optimum conditions for benzo[a]pyrene extraction from soil are described including the soil treatment by subcritical water at 250 °C and 100 atm for 30 min. The effectiveness of developed method was determined using the matrix spiking recovery technique. A comparative analysis was made to evaluate the results of benzo[a]pyrene extraction from soils using the subcritical water and organic solvents. The advantages of the subcritical water extraction involve the use of ecologically friendly solvent, a shorter time for the analysis and a higher amount of benzo[a]pyrene extracted from soil (96 %. The influence of subcritical water extraction on soil properties was measured the investigation of the processes occurring within soil under the influence the high temperature and pressure. Under appropriate conditions of the experiment there is the destruction of the soil organic matter while the composition of the soil mineral fraction remains practically unchanged.

  11. Matrices and linear transformations

    CERN Document Server

    Cullen, Charles G

    1990-01-01

    ""Comprehensive . . . an excellent introduction to the subject."" - Electronic Engineer's Design Magazine.This introductory textbook, aimed at sophomore- and junior-level undergraduates in mathematics, engineering, and the physical sciences, offers a smooth, in-depth treatment of linear algebra and matrix theory. The major objects of study are matrices over an arbitrary field. Contents include Matrices and Linear Systems; Vector Spaces; Determinants; Linear Transformations; Similarity: Part I and Part II; Polynomials and Polynomial Matrices; Matrix Analysis; and Numerical Methods. The first

  12. Fragmentation analysis of water-soluble atmospheric organic matter using ultrahigh-resolution FT-ICR mass spectrometry.

    Science.gov (United States)

    Leclair, Jeffrey P; Collett, Jeffrey L; Mazzoleni, Lynn R

    2012-04-17

    Isolated water-soluble atmospheric organic matter (AOM) analytes extracted from radiation fogwater samples were analyzed using collision induced dissociation with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Tandem mass analysis was performed on several mass ranges between 100 and 400 Da to characterize the functional groups of AOM species. Compounds containing nitrogen and/or sulfur were targeted because of the high number of oxygen atoms contained in their molecular formulas. Due to the large number of isobaric ions in the precursor isolation ranges, large numbers of product ions resulted from collision induced dissociation. Common neutral losses were assigned by matching the molecular formulas of the expected product ions with the detected product ions within the appropriate mass spectra. Since polar functional groups are expected to affect the hygroscopic properties of aerosols, the losses of H(2)O, CO(2), CH(3)OH, HNO(3), CH(3)NO(3), SO(3), SO(4) and combinations of these were specifically targeted. Among the 421 compounds studied, the most frequently observed neutral losses were CO(2) (54%), H(2)O (43%) and CH(3)OH (40%). HNO(3) losses were observed for 63% of the studied nitrogen containing compounds and 33% of the studied compounds containing both nitrogen and sulfur. SO(3) losses were observed for 85% of the studied sulfur containing compounds and 42% of studied compounds containing both nitrogen and sulfur. A number of molecular formulas matching those of monoterpene ozonolysis SOA were observed; they include organonitrates, organosulfates, and nitroxy-organosulfates. Overall, the results of fragmentation analysis of 400+ individual molecular precursors elucidate the complexity and multifunctional nature of the isolated water-soluble AOM.

  13. 2,6-Bis(benzo[b]thiophen-2-yl-3,7-dipentadecyltetrathienoacene (DBT-TTAR2 as an Alternative of Highly Soluble p-type Organic Semiconductor for Organic Thin Film Transistor (OTFT Application

    Directory of Open Access Journals (Sweden)

    Mery B. Supriadi

    2013-03-01

    Full Text Available A new compound of organic semiconductor based on tetrathienoacene (TTA derivatives, DBT-TTAR2 was synthesized and characterized. The corporation of dibenzo[b,d]thiophene (DBT group and alkyl substituent in both ends of TTA core have a significant effect on their π-π molecular conjugation length, energy gaps value and solubility properties. DBT-TTAR2 is fabricated as p-type organic semiconductor of organic thin film transistor (OTFT by solution process at Industrial Technology Research Institute, Taiwan. A good optical, electrochemical, and thermal properties of DBT-TTAR2 showed that its exhibits a better performance as highly soluble p-type organic semiconductor.

  14. Structural signatures of water-soluble organic aerosols in contrasting environments in South America and Western Europe.

    Science.gov (United States)

    Duarte, Regina M B O; Matos, João T V; Paula, Andreia S; Lopes, Sónia P; Pereira, Guilherme; Vasconcellos, Pérola; Gioda, Adriana; Carreira, Renato; Silva, Artur M S; Duarte, Armando C; Smichowski, Patricia; Rojas, Nestor; Sanchez-Ccoyllo, Odon

    2017-08-01

    This study describes and compares the key structural units present in water-soluble organic carbon (WSOC) fraction of atmospheric aerosols collected in different South American (Colombia - Medellín and Bogotá, Peru - Lima, Argentina - Buenos Aires, and Brazil - Rio de Janeiro, São Paulo, and Porto Velho, during moderate (MBB) and intense (IBB) biomass burning) and Western European (Portugal - Aveiro and Lisbon) locations. Proton nuclear magnetic resonance ( 1 H NMR) spectroscopy was employed to assess the relative distribution of non-exchangeable proton functional groups in aerosol WSOC of diverse origin, for the first time to the authors' knowledge in South America. The relative contribution of the proton functional groups was in the order H-C > H-C-C= > H-C-O > Ar-H, except in Porto Velho during MBB, Medellín, Bogotá, and Buenos Aires, for which the relative contribution of H-C-O was higher than that of H-C-C=. The 1 H NMR source attribution confirmed differences in aging processes or regional sources between the two geographic regions, allowing the differentiation between urban combustion-related aerosol and biological particles. The aerosol WSOC in Aveiro, Lisbon, and Rio de Janeiro during summer are more oxidized than those from the remaining locations, indicating the predominance of secondary organic aerosols. Fresh emissions, namely of smoke particles, becomes important during winter in Aveiro and São Paulo, and in Porto Velho during IBB. The biosphere is an important source altering the chemical composition of aerosol WSOC in South America locations. The source attribution in Medellín, Bogotá, Buenos Aires, and Lima confirmed the mixed contributions of biological material, secondary formation, as well as urban and biomass burning emissions. Overall, the information and knowledge acquired in this study provide important diagnostic tools for future studies aiming at understanding the water-soluble organic aerosol problem, their sources and

  15. Functional characterization of the water-soluble organic carbon of size-fractionated aerosol in the southern Mississippi Valley

    Science.gov (United States)

    Chalbot, M.-C. G.; Brown, J.; Chitranshi, P.; Gamboa da Costa, G.; Pollock, E. D.; Kavouras, I. G.

    2014-06-01

    The chemical content of water-soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for periods when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp magnetic resonance (1H-NMR). The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m-3 for particles with 1.5 fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosols and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from -26.81 ± 0.18‰ for the smallest particles to -25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.

  16. Functional characterization of the water-soluble organic carbon of size fractionated aerosol in the Southern Mississippi Valley

    Science.gov (United States)

    Chalbot, M.-C. G.; Brown, J.; Chitranshi, P.; Gamboa da Costa, G.; Pollock, E. D.; Kavouras, I. G.

    2014-02-01

    The chemical content of the water soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to: (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for the period when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp magnetic resonance. The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m-3 for particles with 0.96 fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosol and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from -26.81 ± 0.18‰ for the smallest particles to -25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.

  17. Effect of Gamma Irradiation and Coagualtion on the Molegular Weight Distribution of Soluble Organic Substances in Paper Mill Effluent

    Energy Technology Data Exchange (ETDEWEB)

    Shijun, He; Jianlong, Wang [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); Jianxin, Wan; Mengmeng, Sun [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070 (China); Longfei, Ye [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)

    2012-07-01

    In order to look into the insights of the influence of gamma irradiation and coagulation on the molecular weight distribution (MWD) of soluble organic substances in real paper mill effluent, various parameters of wastewater samples before and after treated were investigated, including chemical oxygen demand (COD), biochemical oxygen demand (BOD{sub 5}), dissolved organic carbon (DOC) and absorbance at 254 nm wavelength (UV{sub 254}) as well. In addition, the effects of irradiation on oxygen uptake and on acute toxicity were also presented. The results showed that irradiation alone cannot promote the biodegradability and oxygen uptake as originally expected. The whole acute toxicity of samples was reduced after gamma irradiation. On the other side, coagulation can not only effectively eliminate the sectors with high molecular weight (MW>3000 Dalton, in short HMW), but also improve the capacity of ionizing irradiation initiated the transformation of medium molecular weight (1000 Dalton

  18. Effect of Gamma Irradiation and Coagualtion on the Molegular Weight Distribution of Soluble Organic Substances in Paper Mill Effluent

    International Nuclear Information System (INIS)

    He Shijun; Wang Jianlong; Wan Jianxin; Sun Mengmeng; Ye Longfei

    2012-01-01

    In order to look into the insights of the influence of gamma irradiation and coagulation on the molecular weight distribution (MWD) of soluble organic substances in real paper mill effluent, various parameters of wastewater samples before and after treated were investigated, including chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), dissolved organic carbon (DOC) and absorbance at 254 nm wavelength (UV 254 ) as well. In addition, the effects of irradiation on oxygen uptake and on acute toxicity were also presented. The results showed that irradiation alone cannot promote the biodegradability and oxygen uptake as originally expected. The whole acute toxicity of samples was reduced after gamma irradiation. On the other side, coagulation can not only effectively eliminate the sectors with high molecular weight (MW>3000 Dalton, in short HMW), but also improve the capacity of ionizing irradiation initiated the transformation of medium molecular weight (1000 Dalton< MW<3000 Dalton, in short MMW) into low molecular weight (MW<1000 Dalton, in short LWM), which is readily degraded by the subsequently activated sludge process. (author)

  19. Investigating differences in the root to shoot transfer and xylem sap solubility of organic compounds between zucchini, squash and soybean using a pressure chamber method.

    Science.gov (United States)

    Garvin, Naho; Doucette, William J; White, Jason C

    2015-07-01

    A pressure chamber method was used to examine differences in the root to shoot transfer and xylem sap solubility of caffeine (log Kow=-0.07), triclocarban (log Kow=3.5-4.2) and endosulfan (log Kow=3.8-4.8) for zucchini (cucurbita pepo ssp pepo), squash (cucurbita pepo ssp ovifera), and soybean (glycine max L.). Transpiration stream concentration factors (TSCF) for caffeine (TSCF=0.8) were statistically equivalent for all plant species. However, for the more hydrophobic endosulfan and triclocarban, the TSCF values for zucchini (TSCF=0.6 and 0.4, respectively) were 3 and 10 times greater than the soybean and squash (TSCF=0.2 and 0.05, respectively). The difference in TSCF values was examined by comparing the measured solubilities of caffeine, endosulfan and triclocarban in deionized water to those in soybean and zucchini xylem saps using a modified shake flask method. The measured solubility of organic contaminants in xylem sap has not previously been reported. Caffeine solubilities in the xylem saps of soybean and zucchini were statistically equal to deionized water (21500mgL(-1)) while endosulfan and triclocarban solubilities in the zucchini xylem sap were significantly greater (0.43 and 0.21mgL(-1), respectively) than that of the soybean xylem sap (0.31 and 0.11mgL(-1), respectively) and deionized water (0.34 and 0.11mgL(-1), respectively). This suggests that the enhanced root to shoot transfer of hydrophobic organics reported for zucchini is partly due to increased solubility in the xylem sap. Further xylem sap characterization is needed to determine the mechanism of solubility enhancement. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Molecular characterization of water soluble organic nitrogen in marine rainwater by ultra-high resolution electrospray ionization mass spectrometry

    Directory of Open Access Journals (Sweden)

    K. E. Altieri

    2012-04-01

    Full Text Available Atmospheric water soluble organic nitrogen (WSON is a subset of the complex organic matter in aerosols and rainwater, which impacts cloud condensation processes and aerosol chemical and optical properties and may play a significant role in the biogeochemical cycle of N. However, its sources, composition, connections to inorganic N, and variability are largely unknown. Rainwater samples were collected on the island of Bermuda (32.27° N, 64.87° W, which experiences both anthropogenic and marine influenced air masses. Samples were analyzed by ultra-high resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry to chemically characterize the WSON. Elemental compositions of 2281 N containing compounds were determined over the mass range m/z+ 50 to 500. The five compound classes with the largest number of elemental formulas identified, in order from the highest number of formulas to the lowest, contained carbon, hydrogen, oxygen, and nitrogen (CHON+, CHON compounds that contained sulfur (CHONS+, CHON compounds that contained phosphorus (CHONP+, CHON compounds that contained both sulfur and phosphorus (CHONSP+, and compounds that contained only carbon, hydrogen, and nitrogen (CHN+. Compared to rainwater collected in the continental USA, average O:C ratios of all N containing compound classes were lower in the marine samples whereas double bond equivalent values were higher, suggesting a reduced role of secondary formation mechanisms. Despite their prevalence in continental rainwater, no organonitrates or nitrooxy-organosulfates were detected, but there was an increased presence of organic S and organic P containing compounds in the marine rainwater. Cluster analysis showed a clear chemical distinction between samples collected during the cold season (October to March which have anthropogenic air mass origins and samples collected during the warm season (April to September with remote

  1. On linear correlation between interfacial tension of water-solvent interface solubility of water in organic solvents and parameters of diluent effect scale

    International Nuclear Information System (INIS)

    Mezhov, Eh.A.; Khananashvili, N.L.; Shmidt, V.S.

    1988-01-01

    Presence of linear correlation between water solubility in nonmiscible with it organic solvents, interfacial tension of water-solvent interface, on the one hand, and solvent effect scale parameters and these solvents π* - on the other hand, is established. It allows, using certain tabular parameters of solvent effect or each solvent π*, to predict values of interfacial tension and water solubility for corresponding systems. It is shown, that solvent effect scale allows to predict values more accurately, than other known solvent scales, as it in contrast to other scales characterizes solvents, which are in equilibrium with water

  2. Size distributions of hydrophilic and hydrophobic fractions of water-soluble organic carbon in an urban atmosphere in Hong Kong

    Science.gov (United States)

    Wang, Nijing; Yu, Jian Zhen

    2017-10-01

    Water-soluble organic carbon (WSOC) is a significant part of ambient aerosol and plays an active role in contributing to aerosol's effect on visibility degradation and radiation budget through its interactions with atmospheric water. Size-segregated aerosol samples in the range of 0.056-18 μm were collected using a ten-stage impactor sampler at an urban site in Hong Kong over one-year period. The WSOC samples were separated into hydrophilic (termed WSOC_h) and hydrophobic fractions (i.e., the humic-like substances (HULIS) fraction) through solid-phase extraction procedure. Carbon in HULIS accounted for 40 ± 14% of WSOC. The size distribution of HULIS was consistently characterized in all seasons with a dominant droplet mode (46-71%) and minor condensation (9.0-18%) and coarse modes (20-35%). The droplet mode had a mass median aerodynamic diameter in the range of 0.7-0.8 μm. This size mode showed the largest seasonal variation in abundance, lowest in the summer (0.41 μg/m3) and highest in the winter (3.3 μg/m3). WSOC_h also had a dominant droplet mode, but was more evenly distributed among different size modes. Inter-species correlations within the same size mode suggest that the condensation-mode HULIS was partly associated with combustion sources and the droplet-mode was strongly associated with secondary sulfate formation and biomass burning particle aging processes. There is evidence to suggest that the coarse-mode HULIS largely originated from coagulation of condensation-mode HULIS with coarse soil/sea salt particles. The formation process and possible sources of WSOC_h was more complicated and multiple than HULIS and need further investigation. Our measurements indicate that WSOC components contributed a dominant fraction of water-soluble aerosol mass in particles smaller than 0.32 μm while roughly 20-30% in the larger particles.

  3. Enhancement of sensitivity in the determination of organic trace compounds in complex matrices with liquid chromatography-mass spectrometry (LC-MS)

    International Nuclear Information System (INIS)

    Mascher, D.G.

    2002-05-01

    The PhD-thesis deals with 'enhancement of sensitivity in the determination of organic trace compounds in complex matrices with liquid chromatography-mass spectrometry (LC-MS)'. Almost the most important factor is the enhancement of the ionization yield with Atmospheric Pressure Chemical Ionization (APCI) or Electrospray Ionization (ESI) in LC-MS. Ionization yields of different compounds can vary by a factor of 10000. Three ways to solve this problem of little ionization yield were tried: 1) Modification of the mobile phase in HPLC 2) Chemical modification of the analytes 3) A new type of ionization called Atmospheric Pressure Photo Ionization (APPI). ad 1) By using specific additives to mobile phases ion suppression that might derive from an ion pair reagent that was necessary for chromatography could be omitted. General remarks cannot be done. ad 2) Chemical modification or so called derivatization is well known for UV- and fluorescence-detection for a long period of time. As substances containing nitrogene (e.g. primary, secondary or tertiary amines) often have good ionization yields, poor or relatively poor ionizable substances like carboxylic acids, sugars and partially phenolic steroids were used as analytes for derivatization reactions. By using Dansyl as Dansylchlorid or Dansylhydrazine a basic derivatization agent could be found that ionizes very well. A 200 times more sensitive determination of estrogenes is possible after derivatization with Dansylchlorid. Using a tandem-mass-spectrometer a lower limit of quantification of 2 pg/mL plasma could be reached by using 1 mL of plasma. For ketones like carvon and campher an enhancement by a factor of 500 and 4000 could be reached by using Dansylhydrazine as the derivatization agent. For fatty acids DMEQ as derivatization agent enhanced the sensitivity by a factor of 20 to 100. ad 3) APPI as a new ionization mode showed really good results for specific molecules. Relatively unpolar substances as diphenylsulfide

  4. Realm of Matrices

    Indian Academy of Sciences (India)

    IAS Admin

    harmonic analysis and complex analysis, in ... gebra describes not only the study of linear transforma- tions and .... special case of the Jordan canonical form of matrices. ..... Richard Bronson, Schaum's Outline Series Theory And Problems Of.

  5. Profiling contents of water-soluble metabolites and mineral nutrients to evaluate the effects of pesticides and organic and chemical fertilizers on tomato fruit quality.

    Science.gov (United States)

    Watanabe, Masami; Ohta, Yuko; Licang, Sun; Motoyama, Naoki; Kikuchi, Jun

    2015-02-15

    In this study, the contents of water-soluble metabolites and mineral nutrients were measured in tomatoes cultured using organic and chemical fertilizers, with or without pesticides. Mineral nutrients and water-soluble metabolites were determined by inductively coupled plasma-atomic emission spectrometry and (1)H nuclear magnetic resonance spectrometry, respectively, and results were analysed by principal components analysis (PCA). The mineral nutrient and water-soluble metabolite profiles differed between organic and chemical fertilizer applications, which accounted for 88.0% and 55.4%, respectively, of the variation. (1)H-(13)C-hetero-nuclear single quantum coherence experiments identified aliphatic protons that contributed to the discrimination of PCA. Pesticide application had little effect on mineral nutrient content (except Fe and P), but affected the correlation between mineral nutrients and metabolites. Differences in the content of mineral nutrients and water-soluble metabolites resulting from different fertilizer and pesticide applications probably affect tomato quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Comparison of structural features of water-soluble organic matter from atmospheric aerosols with those of aquatic humic substances

    Science.gov (United States)

    Duarte, Regina M. B. O.; Santos, Eduarda B. H.; Pio, Casimiro A.; Duarte, Armando C.

    Elemental analysis, Fourier transform infrared coupled to attenuated total reflectance (FTIR-ATR) and solid-state cross polarization with magic angle spinning- 13C-nuclear magnetic resonance (CPMAS 13C NMR) spectroscopies were used to compare the chemical features of water-soluble organic compounds (WSOC) from atmospheric aerosols with those of aquatic humic and fulvic acids. The influence of different meteorological conditions on the structural composition of aerosol WSOC was also evaluated. Prior to the structural characterisation, the WSOC samples were separated into hydrophobic acids and hydrophilic acids fractions by using a XAD-8/XAD-4 isolation procedure. Results showed that WSOC hydrophobic acids are mostly aliphatic (40-62% of total NMR peak area), followed by oxygenated alkyls (15-21%) and carboxylic acid (5.4-13.4%) functional groups. Moreover, the aromatic content of aerosol WSOC samples collected between autumn and winter seasons is higher (˜18-19%) than that of samples collected during warmer periods (˜6-10%). The presence of aromatic signals typical of lignin-derived structures in samples collected during low-temperature conditions highlights the major contribution of wood burning processes in domestic fireplaces into the bulk chemical properties of WSOC from aerosols. According to our investigations, aerosol WSOC hydrophobic acids and aquatic fulvic and humic acids hold similar carbon functional groups; however, they differ in terms of the relative carbon distribution. Elemental analysis indicates that H and N contents of WSOC hydrophobic acids samples surpass those of aquatic fulvic and humic acids. In general, the obtained results suggest that WSOC hydrophobic acids have a higher aliphatic character and a lower degree of oxidation than those of standard fulvic and humic acids. The study here reported suggests that aquatic fulvic and humic acids may not be good models for WSOC from airborne particulate matter.

  7. Source identification of water-soluble organic aerosols at a roadway site using a positive matrix factorization analysis.

    Science.gov (United States)

    Park, Seungshik; Cho, Sung Yong; Bae, Min-Suk

    2015-11-15

    Daily PM2.5 measurements were carried out at a local roadway every sixth day from May 2011 to August 2013 to obtain seasonal quantitative information on the primary and secondary sources of two water-soluble organic carbon (WSOC) fractions. Filter samples were analyzed for OC, elemental carbon (EC), WSOC, hydrophilic and hydrophobic WSOC fractions (WSOC(HPI) and WSOC(HPO)), and ionic species. An XAD solid phase extraction method and a total organic carbon analyzer were used to isolate the two WSOC fractions and determine their amounts, respectively. The WSOC/OC and WSOC(HPI)/WSOC ratios were 0.62±0.13 and 0.47±0.14, respectively. Similar seasonal profiles in EC, OC, and WSOC concentrations were observed, with higher concentrations occurring in the cold season and lower concentrations in the warm season. However, opposite results were obtained in WSOC/OC and WSOC(HPI)/WSOC ratios, with the higher in the warm season and the lower in the cold season. Correlation analyses indicated that two WSOC fractions in winter were likely attributed to secondary formation processes, biomass burning (BB), and traffic emissions, while WSOC(HPI) observed in other seasons were associated with secondary formation processes similar to those of oxalate and secondary inorganic species. A positive matrix factorization (PMF) model was employed to investigate the sources of two WSOC fractions. PMF indicated that concentrations of WSOC fractions were affected by five sources: secondary NO3(-) related, secondary SO4(2-) and oxalate related, traffic emissions, BB emissions, and sea-salt. Throughout the study period, secondary organic aerosols were estimated to be the most dominant contributor of WSOC fractions, with higher contributions occurring in the warm seasons. The contribution of secondary aerosol formation processes (NO3(-) related+SO4(2-) and oxalate related) to WSOC(HPI) and WSOC(HPO) was on an average 56.2% (45.0-73.8%) and 47.7% (39.6-52.1%), respectively. The seasonal average

  8. Chemiluminescence in cryogenic matrices

    Science.gov (United States)

    Lotnik, S. V.; Kazakov, Valeri P.

    1989-04-01

    The literature data on chemiluminescence (CL) in cryogenic matrices have been classified and correlated for the first time. The role of studies on phosphorescence and CL at low temperatures in the development of cryochemistry is shown. The features of low-temperature CL in matrices of nitrogen and inert gases (fine structure of spectra, matrix effects) and the data on the mobility and reactivity of atoms and radicals at very low temperatures are examined. The trends in the development of studies on CL in cryogenic matrices, such as the search for systems involving polyatomic molecules and extending the forms of CL reactions, are followed. The reactions of active nitrogen with hydrocarbons that are accompanied by light emission and CL in the oxidation of carbenes at T >= 77 K are examined. The bibliography includes 112 references.

  9. Matrices in Engineering Problems

    CERN Document Server

    Tobias, Marvin

    2011-01-01

    This book is intended as an undergraduate text introducing matrix methods as they relate to engineering problems. It begins with the fundamentals of mathematics of matrices and determinants. Matrix inversion is discussed, with an introduction of the well known reduction methods. Equation sets are viewed as vector transformations, and the conditions of their solvability are explored. Orthogonal matrices are introduced with examples showing application to many problems requiring three dimensional thinking. The angular velocity matrix is shown to emerge from the differentiation of the 3-D orthogo

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

    Science.gov (United States)

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

    2017-04-01

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

  11. Self-organizing maps as a chemometric tool for aromatic pattern recognition of soluble coffee - doi: 10.4025/actascitechnol.v34i1.10892

    Directory of Open Access Journals (Sweden)

    Evandro Bona

    2011-11-01

    Full Text Available The electronic nose (EN is an instrument very used for food flavor analysis. However, it is also necessary to integrate the equipment with a multivariable pattern recognition system, and to this end the principal component analysis (PCA is the first choice. Alternatively, self-organizing maps (SOM had been also suggested, since they are a nonlinear and reliable technique. In this study SOM were used to distinguish soluble coffee according to EN data. The proposed methodology had identified all of the seven coffees evaluated; in addition, the groups and relationships detected were similar to those obtained through PCA. Also, the analysis of network weights allowed gathering the e-nose sensors into 4 groups according to the behavior regarding the samples. Results confirm SOM as an efficient tool to EN data pos-processing, and have showed the methodology as a promising choice for the development of new products and quality control of soluble coffee.

  12. Plutonium solubilities

    International Nuclear Information System (INIS)

    Puigdomnech, I.; Bruno, J.

    1991-02-01

    Thermochemical data has been selected for plutonium oxide, hydroxide, carbonate and phosphate equilibria. Equilibrium constants have been evaluated in the temperature range 0 to 300 degrees C at a pressure of 1 bar to T≤100 degrees C and at the steam saturated pressure at higher temperatures. Measured solubilities of plutonium that are reported in the literature for laboratory experiments have been collected. Solubility data on oxides, hydroxides, carbonates and phosphates have been selected. No solubility data were found at temperatures higher than 60 degrees C. The literature solubility data have been compared with plutonium solubilities calculated with the EQ3/6 geochemical modelling programs, using the selected thermodynamic data for plutonium. (authors)

  13. Infinite matrices and sequence spaces

    CERN Document Server

    Cooke, Richard G

    2014-01-01

    This clear and correct summation of basic results from a specialized field focuses on the behavior of infinite matrices in general, rather than on properties of special matrices. Three introductory chapters guide students to the manipulation of infinite matrices, covering definitions and preliminary ideas, reciprocals of infinite matrices, and linear equations involving infinite matrices.From the fourth chapter onward, the author treats the application of infinite matrices to the summability of divergent sequences and series from various points of view. Topics include consistency, mutual consi

  14. Capture Matrices Handbook

    Science.gov (United States)

    2014-04-01

    materials, the affinity ligand would need identification , as well as chemistries that graft the affinity ligand onto the surface of magnetic...ACTIVE CAPTURE MATRICES FOR THE DETECTION/ IDENTIFICATION OF PHARMACEUTICALS...6 As shown in Figure 2.3-1a, the spectra exhibit similar baselines and the spectral peaks lineup . Under these circumstances, the spectral

  15. On the water-soluble organic nitrogen concentration and mass size distribution during the fog season in the Po Valley, Italy.

    Science.gov (United States)

    Montero-Martínez, Guillermo; Rinaldi, Matteo; Gilardoni, Stefania; Giulianelli, Lara; Paglione, Marco; Decesari, Stefano; Fuzzi, Sandro; Facchini, Maria Cristina

    2014-07-01

    The study of organic nitrogen gained importance in recent decades due to its links with acid rain, pollution, and eutrophication. In this study, aerosol and fog water samples collected from two sites in Italy during November 2011 were analyzed to characterize their organic nitrogen content. Organic nitrogen contributed 19-25% of the total soluble nitrogen in the aerosol and around 13% in fog water. The largest water soluble organic nitrogen concentrations in the PM1.2 fraction occurred during the diurnal period with mean values of 2.03 and 2.16 μg-N m(-3) (154 and 145 nmol-N m(-3)) at Bologna and San Pietro Capofiume (SPC), respectively. The mean PM10 WSON concentration during diurnal periods at SPC was 2.30 μg-N m(-3) (164 nmol-N m(-3)) while it was 1.34 and 0.82 μg-N m(-3) (95.7 and 58.5 nmol-N m(-3)) in the night and fog water samples, respectively. Aerosol mass distribution profiles obtained during fog changed significantly with respect to those estimated in periods without fog periods due to fog scavenging, which proved to be over 80% efficient. Linear correlations suggested secondary processes related to combustion and, to a lesser extent, biomass burning, as plausible sources of WSON. Regarding the inorganic nitrogen fraction, the results showed that ammonium was the largest soluble inorganic nitrogen component in the samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Introduction to matrices and vectors

    CERN Document Server

    Schwartz, Jacob T

    2001-01-01

    In this concise undergraduate text, the first three chapters present the basics of matrices - in later chapters the author shows how to use vectors and matrices to solve systems of linear equations. 1961 edition.

  17. The Changes in Color, Soluble Sugars, Organic Acids, Anthocyanins and Aroma Components in “Starkrimson” during the Ripening Period in China

    Directory of Open Access Journals (Sweden)

    Yulian Liu

    2016-06-01

    Full Text Available “Starkrimson” is a traditional apple cultivar that was developed a long time ago and was widely cultivated in the arid region of the northern Wei River of China. However, little information regarding the quality characteristics of “Starkrimson” fruit has been reported in this area. To elucidate these characteristics, the color, soluble sugars, organic acids, anthocyanins and aroma components were measured during the ripening period through the use of high performance liquid chromatography (HPLC and gas chromatography-mass spectrometry (GC-MS. The results indicated that the changes in anthocyanin contents took place later than the changes in the Commission International Eclairage (CIE parameters. Meanwhile, cyanidin 3-galactoside (cy3-gal, fructose, sucrose, glucose and malic acid were the primary organic compounds, and 1-butanol-2-methyl-acetate, 2-hexenal and 1-hexanol were the most abundant aroma components in the skin. Furthermore, rapidly changing soluble sugars and organic acid synchronization took place in the early ripening period, while rapidly changing aroma components occurred later, on the basis of fresh weight. This result suggested that the production of aroma components might be a useful index of apple maturity.

  18. Graphs and matrices

    CERN Document Server

    Bapat, Ravindra B

    2014-01-01

    This new edition illustrates the power of linear algebra in the study of graphs. The emphasis on matrix techniques is greater than in other texts on algebraic graph theory. Important matrices associated with graphs (for example, incidence, adjacency and Laplacian matrices) are treated in detail. Presenting a useful overview of selected topics in algebraic graph theory, early chapters of the text focus on regular graphs, algebraic connectivity, the distance matrix of a tree, and its generalized version for arbitrary graphs, known as the resistance matrix. Coverage of later topics include Laplacian eigenvalues of threshold graphs, the positive definite completion problem and matrix games based on a graph. Such an extensive coverage of the subject area provides a welcome prompt for further exploration. The inclusion of exercises enables practical learning throughout the book. In the new edition, a new chapter is added on the line graph of a tree, while some results in Chapter 6 on Perron-Frobenius theory are reo...

  19. Decreasing DOC trends in soil solution along the hillslopes at two IM sites in southern Sweden--geochemical modeling of organic matter solubility during acidification recovery.

    Science.gov (United States)

    Löfgren, Stefan; Gustafsson, Jon Petter; Bringmark, Lage

    2010-12-01

    Numerous studies report increased concentrations of dissolved organic carbon (DOC) during the last two decades in boreal lakes and streams in Europe and North America. Recently, a hypothesis was presented on how various spatial and temporal factors affect the DOC dynamics. It was concluded that declining sulphur deposition and thereby increased DOC solubility, is the most important driver for the long-term DOC concentration trends in surface waters. If this recovery hypothesis is correct, the DOC levels should increase both in the soil solution as well as in the surrounding surface waters as soil pH rises and the ionic strength declines due to the reduced input of SO(4)(2-) ions. In this project a geochemical model was set up to calculate the net humic charge and DOC solubility trends in soils during the period 1996-2007 at two integrated monitoring sites in southern Sweden, showing clear signs of acidification recovery. The Stockholm Humic Model was used to investigate whether the observed DOC solubility is related to the humic charge and to examine how pH and ionic strength influence it. Soil water data from recharge and discharge areas, covering both podzols and riparian soils, were used. The model exercise showed that the increased net charge following the pH increase was in many cases counteracted by a decreased ionic strength, which acted to decrease the net charge and hence the DOC solubility. Thus, the recovery from acidification does not necessarily have to generate increasing DOC trends in soil solution. Depending on changes in pH, ionic strength and soil Al pools, the trends might be positive, negative or indifferent. Due to the high hydraulic connectivity with the streams, the explanations to the DOC trends in surface waters should be searched for in discharge areas and peat lands. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Hierarchical quark mass matrices

    International Nuclear Information System (INIS)

    Rasin, A.

    1998-02-01

    I define a set of conditions that the most general hierarchical Yukawa mass matrices have to satisfy so that the leading rotations in the diagonalization matrix are a pair of (2,3) and (1,2) rotations. In addition to Fritzsch structures, examples of such hierarchical structures include also matrices with (1,3) elements of the same order or even much larger than the (1,2) elements. Such matrices can be obtained in the framework of a flavor theory. To leading order, the values of the angle in the (2,3) plane (s 23 ) and the angle in the (1,2) plane (s 12 ) do not depend on the order in which they are taken when diagonalizing. We find that any of the Cabbibo-Kobayashi-Maskawa matrix parametrizations that consist of at least one (1,2) and one (2,3) rotation may be suitable. In the particular case when the s 13 diagonalization angles are sufficiently small compared to the product s 12 s 23 , two special CKM parametrizations emerge: the R 12 R 23 R 12 parametrization follows with s 23 taken before the s 12 rotation, and vice versa for the R 23 R 12 R 23 parametrization. (author)

  1. The Solubility of Cr-Organic Produced by Hydrolysis, Bioprocess and Bioremediation and its Effect on Fermented Rate, Digestibility and Rumen Microbe Population (in vitro

    Directory of Open Access Journals (Sweden)

    UH Tanuwiria

    2010-09-01

    Full Text Available The research was conducted to study the production of organic chromium from the leather tanning waste and its effect on in vitro rumen fermentation activities. The research was divided into two phases. The first phase was production of organic chromium by alkali hydrolysis, S cereviceae bioprocess, and duckweed bioremediation that perceived solubility in neutral and acid solution. The second phase was the supplementation of organic-Cr in ration seen from in-vitro fermented rate, digestibility and microbe rumen population. Research was conducted experimentally using 4x4 factorial patterns, on the basis of Completely Randomized Design (CRD with three replications in each experimental unit. The first factor was the type of organic-Cr and the second factor was the supplement in ration at four levels, 1, 2, 3 and 4 ppm. The results of this research indicated that organic chromium can be synthesized by alkali hydrolysis, S cereviseae bioprocess and the activity of duckweed bioremediation. Among the three of processes referred, the highest level of Cr was obtained from S cereviseae bioprocess that was originated from leather-tanning waste. The levels of organic-Cr that was resulted from alkali hydrolysis, bioprocess from Cl3Cr.6H2O, bioprocess from Cr leather-tanning waste, and from duckweed bioremediation were 354, 1011, 3833 and 310 mg/kg, respectively. Organic-Cr characteristic of each product has relatively similar in ferment ability, dry matter and organic matter digestibility and rumen ecosystem. There is an indication that dry matter and organic matter digestibility and rumen microbe population in ration that was added with organic Cr from alkali hydrolysis was higher than other supplements. (Animal Production 12(3: 175-183 (2010Key Words: organic-Cr, rumen fermentation activities, rumen microbe population

  2. Application of different methodologies in the preparation of organic matrices for determination of trace elements by differential pulse anodic stripping voltammetry

    International Nuclear Information System (INIS)

    Sisti, Cristina

    2001-01-01

    The determination of trace elements in food samples is of great importance for the human health, considering the factors of essentiality and toxicity. On the other hand, the chemical analysis is largely affected for the steps of sample preparation; laboratory contamination of the sample and the reagents or still volatilization and losses of the elements. If these parameters are not controlled the achieved precision and accuracy could be low. In this work, the content of zinc, cadmium, lead and copper was determined in adults diet samples collected by duplicate portion technique and bovine liver, applying the differential pulse anodic stripping voltametry - (DP-ASV) technique. In the digestion of the matrices in acid medium, conventional methodologies were used, conductive heating in open recipients and equipment with microwaves source in open and closed vessels. The best procedure was the sample digestion by microwaves, in closed vessels and the other treatments made in controlled atmosphere with hood laminar-airflow class 100. The established methodology was validated with the use of a certified sample as reference (NIST - bovine liver 1577b). (author)

  3. Partitioning of semi-soluble organic compounds between the water phase and oil droplets in produced water

    Energy Technology Data Exchange (ETDEWEB)

    Faksness, Liv-Guri; Grini, Per Gerhard; Daling, Per S

    2004-04-01

    When selecting produced water treatment technologies, one should focus on reducing the major contributors to the total environmental impact. These are dispersed oil and semi-soluble hydrocarbons, alkylated phenols, and added chemicals. Experiments with produced water have been performed offshore on the Statoil operated platforms Gullfaks C and Statfjord B. These experiments were designed to find how much of the environmentally relevant compounds were dissolved in the water phase and not associated to the dispersed oil in the produced water. Results show that the distribution between the dispersed oil and the water phase varies highly for the different components groups. For example the concentration of PAHs and the C6-C9 alkylated phenols is strongly correlated to the content of dispersed oil. Therefore, the technologies enhancing the removal of dispersed oil have a higher potential for reducing the environmental impact of the produced water than previously considered.

  4. Partitioning of semi-soluble organic compounds between the water phase and oil droplets in produced water

    International Nuclear Information System (INIS)

    Faksness, Liv-Guri; Grini, Per Gerhard; Daling, Per S.

    2004-01-01

    When selecting produced water treatment technologies, one should focus on reducing the major contributors to the total environmental impact. These are dispersed oil and semi-soluble hydrocarbons, alkylated phenols, and added chemicals. Experiments with produced water have been performed offshore on the Statoil operated platforms Gullfaks C and Statfjord B. These experiments were designed to find how much of the environmentally relevant compounds were dissolved in the water phase and not associated to the dispersed oil in the produced water. Results show that the distribution between the dispersed oil and the water phase varies highly for the different components groups. For example the concentration of PAHs and the C6-C9 alkylated phenols is strongly correlated to the content of dispersed oil. Therefore, the technologies enhancing the removal of dispersed oil have a higher potential for reducing the environmental impact of the produced water than previously considered

  5. Solubility of lead and copper in biochar-amended small arms range soils: influence of soil organic carbon and pH.

    Science.gov (United States)

    Uchimiya, Minori; Bannon, Desmond I

    2013-08-14

    Biochar is often considered a strong heavy metal stabilizing agent. However, biochar in some cases had no effects on, or increased the soluble concentrations of, heavy metals in soil. The objective of this study was to determine the factors causing some biochars to stabilize and others to dissolve heavy metals in soil. Seven small arms range soils with known total organic carbon (TOC), cation exchange capacity, pH, and total Pb and Cu contents were first screened for soluble Pb and Cu concentrations. Over 2 weeks successive equilibrations using weak acid (pH 4.5 sulfuric acid) and acetate buffer (0.1 M at pH 4.9), Alaska soil containing disproportionately high (31.6%) TOC had nearly 100% residual (insoluble) Pb and Cu. This soil was then compared with sandy soils from Maryland containing significantly lower (0.5-2.0%) TOC in the presence of 10 wt % (i) plant biochar activated to increase the surface-bound carboxyl and phosphate ligands (PS450A), (ii) manure biochar enriched with soluble P (BL700), and (iii) unactivated plant biochars produced at 350 °C (CH350) and 700 °C (CH500) and by flash carbonization (corn). In weak acid, the pH was set by soil and biochar, and the biochars increasingly stabilized Pb with repeated extractions. In pH 4.9 acetate buffer, PS450A and BL700 stabilized Pb, and only PS450A stabilized Cu. Surface ligands of PS450A likely complexed and stabilized Pb and Cu even under acidic pH in the presence of competing acetate ligand. Oppositely, unactivated plant biochars (CH350, CH500, and corn) mobilized Pb and Cu in sandy soils; the putative mechanism is the formation of soluble complexes with biochar-borne dissolved organic carbon. In summary, unactivated plant biochars can inadvertently increase dissolved Pb and Cu concentrations of sandy, low TOC soils when used to stabilize other contaminants.

  6. Matrices and linear algebra

    CERN Document Server

    Schneider, Hans

    1989-01-01

    Linear algebra is one of the central disciplines in mathematics. A student of pure mathematics must know linear algebra if he is to continue with modern algebra or functional analysis. Much of the mathematics now taught to engineers and physicists requires it.This well-known and highly regarded text makes the subject accessible to undergraduates with little mathematical experience. Written mainly for students in physics, engineering, economics, and other fields outside mathematics, the book gives the theory of matrices and applications to systems of linear equations, as well as many related t

  7. Intermittency and random matrices

    Science.gov (United States)

    Sokoloff, Dmitry; Illarionov, E. A.

    2015-08-01

    A spectacular phenomenon of intermittency, i.e. a progressive growth of higher statistical moments of a physical field excited by an instability in a random medium, attracted the attention of Zeldovich in the last years of his life. At that time, the mathematical aspects underlying the physical description of this phenomenon were still under development and relations between various findings in the field remained obscure. Contemporary results from the theory of the product of independent random matrices (the Furstenberg theory) allowed the elaboration of the phenomenon of intermittency in a systematic way. We consider applications of the Furstenberg theory to some problems in cosmology and dynamo theory.

  8. Dimension from covariance matrices.

    Science.gov (United States)

    Carroll, T L; Byers, J M

    2017-02-01

    We describe a method to estimate embedding dimension from a time series. This method includes an estimate of the probability that the dimension estimate is valid. Such validity estimates are not common in algorithms for calculating the properties of dynamical systems. The algorithm described here compares the eigenvalues of covariance matrices created from an embedded signal to the eigenvalues for a covariance matrix of a Gaussian random process with the same dimension and number of points. A statistical test gives the probability that the eigenvalues for the embedded signal did not come from the Gaussian random process.

  9. Vitaminen in rantsoenen voor biologisch melkvee = Fat soluble vitamins in rations for organic dairy cows en goat

    NARCIS (Netherlands)

    Smolders, G.; Eekeren, van N.J.M.; Neijenhuis, F.

    2005-01-01

    On five organic dairy cow farms during the period spring 2004/2005 feedstuffs and blood samples were taken 3 times to analyse beta carotene, vitamin D and vitamin E (tocopherols). On 3 organic dairy goat farms feeds and blood samples were taken only in spring 2005. Within types of feeds there are

  10. Isolation and Identification of Proteins Secreted by Cells Cultured within Synthetic Hydrogel-Based Matrices.

    Science.gov (United States)

    Sawicki, Lisa A; Choe, Leila H; Wiley, Katherine L; Lee, Kelvin H; Kloxin, April M

    2018-03-12

    Cells interact with and remodel their microenvironment, degrading large extracellular matrix (ECM) proteins (e.g., fibronectin, collagens) and secreting new ECM proteins and small soluble factors (e.g., growth factors, cytokines). Synthetic mimics of the ECM have been developed as controlled cell culture platforms for use in both fundamental and applied studies. However, how cells broadly remodel these initially well-defined matrices remains poorly understood and difficult to probe. In this work, we have established methods for widely examining both large and small proteins that are secreted by cells within synthetic matrices. Specifically, human mesenchymal stem cells (hMSCs), a model primary cell type, were cultured within well-defined poly(ethylene glycol) (PEG)-peptide hydrogels, and these cell-matrix constructs were decellularized and degraded for subsequent isolation and analysis of deposited proteins. Shotgun proteomics using liquid chromatography and mass spectrometry identified a variety of proteins, including the large ECM proteins fibronectin and collagen VI. Immunostaining and confocal imaging confirmed these results and provided visualization of protein organization within the synthetic matrices. Additionally, culture medium was collected from the encapsulated hMSCs, and a Luminex assay was performed to identify secreted soluble factors, including vascular endothelial growth factor (VEGF), endothelial growth factor (EGF), basic fibroblast growth factor (FGF-2), interleukin 8 (IL-8), and tumor necrosis factor alpha (TNF-α). Together, these methods provide a unique approach for studying dynamic reciprocity between cells and synthetic microenvironments and have the potential to provide new biological insights into cell responses during three-dimensional (3D) controlled cell culture.

  11. The Changes of P-fractions and Solubility of Phosphate Rock in Ultisol Treated by Organic Matter and Phosphate Rock

    Directory of Open Access Journals (Sweden)

    Heru Bagus Pulunggono

    2012-09-01

    Full Text Available Phosphorus (P is one of the essential elements for plant, however, its availability is mostly very low in acid soils. It is well documented that application of phosphate rock and organic matter are able to change the level of availability of P-form in acid soils. The objective of the research were to evaluate the changes of P-fractions ( resin-P, NaHCO3-Pi, and NaHCO3-Po and phosphate rock dissolution which were induced by application of organic matter (Imperata cylindrica, Pueraria javanica, dan Colopogonium mucunoides and phosphate rock in Utisol Lampung. The experiment was designed in a completely randomized design with three factors and three replications. The first factor was the types of organic matter (I. cylindrica, P. javanica, and C. mucunoides, the second factor was the rate of organic matter (0, 2.5, and 5%, and the third factor was the rate of phosphate rock (0, 40, and 80 mg P kg-1. The results showed that in the rate of 0 and 1% organic matter, the type of organic matter did not affect P-fraction of NaHCO3-Pi, but in the rate of 2.5 and 5%, NaHCO3-Pi due to application of P. javanica, and C. mucunoides higher than due to application of I. cylindrica. However, the increasing rate of organic matter increased NaHCO3-Pi. Then, P-fraction of Resin-Pi was affected by the type of organic matter, the rate of organic matter, and the rate of phosphate rock, respectively. P-fraction of resin-Pi due to application of P. javanica, and C. mucunoides was higher than due to application of I. cylindrica, but the effect of P. javanica, and C. mucunoides was not different. Increasing the rate of organic matter and phosphate rock increased P-fraction of resin-Pi and NaHCO3-Pi, but P-fraction of NaHCO3-Po was not affected by all treatments. Meanwhile, dissolution of phosphate rock was affected by the kind of organic matter and soil reaction. In the rate of 5% organic matter, dissolution of phosphate rock by application of I. cylindrica (70% was higher

  12. Water soluble organic carbon in aerosols (PM1, PM2.5, PM10) and various precipitation forms (rain, snow, mixed) over the southern Baltic Sea station.

    Science.gov (United States)

    Witkowska, Agnieszka; Lewandowska, Anita U

    2016-12-15

    In the urbanized coastal zone of the Southern Baltic, complex measurements of water soluble organic carbon (WSOC) were conducted between 2012 and 2015, involving atmospheric precipitation in its various forms (rain, snow, mixed) and PM1, PM2.5 and PM10 aerosols. WSOC constituted about 60% of the organic carbon mass in aerosols of various sizes. The average concentration of WSOC was equal to 2.6μg∙m -3 in PM1, 3.6μg∙m -3 in PM2.5 and 4.4μg∙m -3 in PM10. The lowest concentration of WSOC was noted in summer as a result of effective removal of this compound with rainfall. The highest WSOC concentrations in PM2.5 and PM10 aerosols were measured in spring, which should be associated with developing vegetation on land and in the sea. On the other hand, the highest WSOC concentrations in PM1 occurred in winter at low air temperatures and greatest atmospheric stability, when there were increased carbon emissions from fuel combustion in the communal-utility sector and from transportation. WSOC concentrations in precipitation were determined by its form. Mixed precipitation turned out to be the richest in soluble organic carbon (5.1mg·dm -3 ), while snow contained the least WSOC (1.7mg·dm -3 ). Snow and rain cleaned carbon compounds from the atmosphere more effectively when precipitation lasted longer than 24h, while in the case of mixed precipitation WSOC was removed most effectively within the first 24h. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Preparation of detergent-lipase complexes utilizing water-soluble amphiphiles in single aqueous phase and catalysis of transesterifications in homogeneous organic solvents.

    Science.gov (United States)

    Mine, Y; Fukunaga, K; Maruoka, N; Nakao, K; Sugimura, Y

    2000-01-01

    A novel method of preparing detergent-enzyme complexes that can be employed in organic media was developed utilizing newly synthesized water-soluble nonionic gemini-type detergents, N,N-bis(3-D-gluconamidopropyl)-3-(dialkyl-L-glutamatecarbonyl)propanamides (BIG2CnCA: n = 10,12,14,16,18) and N,N-bis(3-D-lactonamidopropyl)-3-(dialkyl-L-glutamatecarbonyl)propanamides (BIL2CnCA: n = 16,18), and nonionic twin-headed detergents, N,N-bis(3-D-gluconamidopropyl)alkanamides (BIG1Cn: n = 12,14,16,18,delta9). This method simply entails mixing a selected enzyme with an appropriate detergent in an aqueous solution followed by lyophilization, and it offers the advantages of enhanced enzymatic activity in organic solvents and eliminates both enzyme loss and the necessity for an organic solvent in the preparation stage. Using various modified lipases originating from Aspergillus niger (Lipase A), Candida rugosa (Lipase C), Pseudomonas cepacia (Lipase P), and porcine pancreas (PPL), prepared using the novel method and detergents, including conventional synthesized nonionic detergents such as dialkyl N-D-glucona-L-glutamates (2CnGE: n = 12,18delta9) and octanoyl-N-methylglucamide (MEGA-8), enantioselective transesterifications of 6-methyl-5-hepten-2-ol (sulcatol) and 2,2-dimethyl-1,3-dioxolane-4-methanol (solketal) with a vinyl or isopropenyl carboxylate were carried out in an organic solvent. The modified lipase activity was influenced by both the lipases and the structure of the detergents. The value for the hydrophile-lipophile balance (HLB) of the detergent provided a means of correlating the structure and the obtained modified lipase activity. For detergents of the same class with a HLB value of approximately 9 and 12, the highest activity was obtained for Lipase A and Lipase P, and Lipase C and PPL, respectively. Among detergents of the same HLB value tested, the gemini-type detergents possessing the most bulky head and tail were most effective as a modifier for lipases of all

  14. Chemical characteristics and acidity of soluble organic substances from a northern hardwood forest floor, central Maine, USA

    International Nuclear Information System (INIS)

    Vance, G.F.; David, M.B.

    1991-01-01

    The authors understanding of the chemistry, structure, and reactions of organic substances in forest floor leachates is limited and incomplete. Therefore, the authors examined the organic and inorganic chemistry of forest floor leachates collected from a hardwood forest in central Maine over a two-year period (1987-1989), including detailed study of dissolved organic carbon (DOC). Seasonal variations in NH 4 + , NO 3 - , K + , and total Al were believed due to organic matter decomposition and release. Leaching of other base cations closely followed that of NO 3 - . Total DOC ranged from 2,228 to 7,193 μmol L -1 with an average of 4,835 μmol L -1 . Monosaccharides and polyphenols constituted 3.9% (range of 3.4 to 4.4%) and 3.0% (2.2 to 3.7%) of the DOC, respectively, which suggests DOC may contain partially oxidized products that are possibly of a lignocellulose nature. Fractionation of the forest floor DOC indicated high organic acid contents (hydrophobic and hydrophilic acids) that averaged 92% of the total DOC. Organic acids were isolated and analyzed for elemental content (C, H, N, and S), and determination of UV absorptivity (E 4 /E 6 ) ratios, CuO oxidation products, FT-IR and 13 C-NMR spectra, and acidity by potentiometric titration. Their FT-IR and 13 C-NMR spectra suggest they are primarily carboxylic acids, with aliphatic and aromatic structure. An organic charge contribution model was developed using titration data, DOC fractionation percentages, and the total DOC in the forest floor leachates. Application of the model to all solutions accounted for 97% of the charge balance deficits

  15. Complex Wedge-Shaped Matrices: A Generalization of Jacobi Matrices

    Czech Academy of Sciences Publication Activity Database

    Hnětynková, Iveta; Plešinger, M.

    2015-01-01

    Roč. 487, 15 December (2015), s. 203-219 ISSN 0024-3795 R&D Projects: GA ČR GA13-06684S Keywords : eigenvalues * eigenvector * wedge-shaped matrices * generalized Jacobi matrices * band (or block) Krylov subspace methods Subject RIV: BA - General Mathematics Impact factor: 0.965, year: 2015

  16. The use of solid sorbents for direct accumulation of organic compounds from water matrices : a review of solid-phase extraction techniques

    NARCIS (Netherlands)

    Liska, I.; Krupcik, J.; Leclercq, P.A.

    1989-01-01

    The main principles of solid-phase extraction techniques are reviewed in this paper. Various solid sorbents can be used as a suitable trap for direct accumulation of organic compounds from aqueous solutions. The trapped analytes can be desorbed by elution with suitably chosen liquid phases. These

  17. Generalisations of Fisher Matrices

    Directory of Open Access Journals (Sweden)

    Alan Heavens

    2016-06-01

    Full Text Available Fisher matrices play an important role in experimental design and in data analysis. Their primary role is to make predictions for the inference of model parameters—both their errors and covariances. In this short review, I outline a number of extensions to the simple Fisher matrix formalism, covering a number of recent developments in the field. These are: (a situations where the data (in the form of ( x , y pairs have errors in both x and y; (b modifications to parameter inference in the presence of systematic errors, or through fixing the values of some model parameters; (c Derivative Approximation for LIkelihoods (DALI - higher-order expansions of the likelihood surface, going beyond the Gaussian shape approximation; (d extensions of the Fisher-like formalism, to treat model selection problems with Bayesian evidence.

  18. Random volumes from matrices

    Energy Technology Data Exchange (ETDEWEB)

    Fukuma, Masafumi; Sugishita, Sotaro; Umeda, Naoya [Department of Physics, Kyoto University,Kitashirakawa Oiwake-cho, Kyoto 606-8502 (Japan)

    2015-07-17

    We propose a class of models which generate three-dimensional random volumes, where each configuration consists of triangles glued together along multiple hinges. The models have matrices as the dynamical variables and are characterized by semisimple associative algebras A. Although most of the diagrams represent configurations which are not manifolds, we show that the set of possible diagrams can be drastically reduced such that only (and all of the) three-dimensional manifolds with tetrahedral decompositions appear, by introducing a color structure and taking an appropriate large N limit. We examine the analytic properties when A is a matrix ring or a group ring, and show that the models with matrix ring have a novel strong-weak duality which interchanges the roles of triangles and hinges. We also give a brief comment on the relationship of our models with the colored tensor models.

  19. Thermodynamic functions for solubility of 3-nitro-o-toluic acid in nine organic solvents from T = (283.15 to 318.15) K and apparent thermodynamic properties of solutions

    International Nuclear Information System (INIS)

    Li, Xinbao; Wang, Mingju; Du, Cunbin; Cong, Yang; Zhao, Hongkun

    2017-01-01

    Highlights: • Solubilities of 3-nitro-o-toluic acid in nine organic solvents were determined. • The solubilities were correlated by using four thermodynamic models. • The mixing properties of solution were computed based on Wilson model. - Abstract: Separation of 3-nitro-o-toluic acid from its isomeric mixtures has essential significance in industry. In this work, by using isothermal saturation method, the solid-liquid equilibrium for 3-nitro-o-toluic acid in nine organic solvents (acetonitrile, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, acetone, 1,4-dioxane and 2-butanone) were obtained experimentally within a temperature range from (283.15 to 318.15) K under atmosphere pressure of 101.2 kPa, and the solubility values of 3-nitro-o-toluic acid in these solvents were determined by a high-performance liquid chromatography. Within the studied temperature range, the mole fraction solubility of 3-nitro-o-toluic acid in selected organic solvents increased with increasing temperature. Except for ethyl acetate, the descending order of the mole fraction solubility values were as follow: 1,4-dioxane > acetone > 2-butanone > methanol > ethanol > isopropanol > n-propanol > acetonitrile. The solubility values determined for 3-nitro-o-toluic acid in the selected solvents were correlated and back calculated with the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of RAD and RMSD obtained with the four models were 0.67% and 4.02 × 10 −4 , respectively. In general, the four thermodynamic models were all acceptable for describing the solubility behaviour of 3-nitro-o-toluic acid in these solvents. In addition, the apparent mixing Gibbs energy, mixing enthalpy, mixing entropy, activity coefficient at infinitesimal concentration and reduced excess enthalpy were calculated. The acquired solubility data and thermodynamic studies would be very important in optimizing the separation process of 3-nitro-o-toluic acid from

  20. Heavy metals and organic pollutants in soils. Concentrations - sorption and solubility - effects on micro-organisms; Schwermetalle und organische Schadstoffe in Boeden. Gehalte - Sorption und Loeslichkeit - Wirkung auf Mikroorganismen

    Energy Technology Data Exchange (ETDEWEB)

    Welp, G.

    2000-07-01

    The thesis comprises six manuscripts published in different journals. Soil protection being the main theme the articles deal with different aspects that represent a necessary scientific basis of a risk assessment for polluted soils. The first step is to look at the total contents of different soil contaminants and to decide whether a pollution is given or not. In chapter II the contents of 18 elements in 335 soil samples of North Rhine-Westphalia are analysed, in order to determine groups of soil samples that are characterized by a certain range of element contents in connection with other common features (e.g., parent material, sampling region, specific source of pollution). The study bases on a detailed inspection of frequency distributions which are evaluated with a parametric method (assuming several single lognormal distributions) and with a nonparametric approach (Kemel density estimation). The latter method proved to be a useful tool to derive background concentrations for toxic elements in soils. It is necessary to differentiate between soluble (mobile, available) and insoluble (immobile, strongly adsorbed, precipitated) fractions of pollutants in soil. The sorption and solubility of pollutants in soils, therefore, is a second important parameter for an appropriate risk assessment. Four papers (chapter III-VI) deal with this aspect. In chapter III sorption and solubility of ten metals in four soil samples is studied. The quantity-intensity relations of eight metals [except Cr(III) and Fe(III)] are governed by sorption and complexation procecces and can be fitted by Freundlich isotherms. In three further papers sorption and solubility experiments with inorganic and organic toxicants are combined with microbial tests in order to detect effects on microorganisms in relation to soil properties. The large data set of about 500 dose-response curves was also used to examine the general reaction patterns of heterogeneous microbial populations under chemical stress

  1. VanderLaan Circulant Type Matrices

    Directory of Open Access Journals (Sweden)

    Hongyan Pan

    2015-01-01

    Full Text Available Circulant matrices have become a satisfactory tools in control methods for modern complex systems. In the paper, VanderLaan circulant type matrices are presented, which include VanderLaan circulant, left circulant, and g-circulant matrices. The nonsingularity of these special matrices is discussed by the surprising properties of VanderLaan numbers. The exact determinants of VanderLaan circulant type matrices are given by structuring transformation matrices, determinants of well-known tridiagonal matrices, and tridiagonal-like matrices. The explicit inverse matrices of these special matrices are obtained by structuring transformation matrices, inverses of known tridiagonal matrices, and quasi-tridiagonal matrices. Three kinds of norms and lower bound for the spread of VanderLaan circulant and left circulant matrix are given separately. And we gain the spectral norm of VanderLaan g-circulant matrix.

  2. Diagonalization of the mass matrices

    International Nuclear Information System (INIS)

    Rhee, S.S.

    1984-01-01

    It is possible to make 20 types of 3x3 mass matrices which are hermitian. We have obtained unitary matrices which could diagonalize each mass matrix. Since the three elements of mass matrix can be expressed in terms of the three eigenvalues, msub(i), we can also express the unitary matrix in terms of msub(i). (Author)

  3. Enhancing Understanding of Transformation Matrices

    Science.gov (United States)

    Dick, Jonathan; Childrey, Maria

    2012-01-01

    With the Common Core State Standards' emphasis on transformations, teachers need a variety of approaches to increase student understanding. Teaching matrix transformations by focusing on row vectors gives students tools to create matrices to perform transformations. This empowerment opens many doors: Students are able to create the matrices for…

  4. Profiling of the Contents of Amino Acids, Water-Soluble Vitamins, Minerals, Sugars and Organic Acids in Turkish Hazelnut Varieties

    Directory of Open Access Journals (Sweden)

    Taş Neslihan Göncüoğlu

    2018-09-01

    Full Text Available Proximate composition, profiles of amino acids, sugars, organic acids, vitamins and minerals of fourteen Turkish hazelnut varieties harvested in 2013 and 2014 were investigated. Glutamic acid, arginine and aspartic acid were the most predominant amino acids, representing of about 50% of hazelnut protein. Individual amino acid profiles showed significant differences depending upon the harvest year (p<0.05. Concentration of sucrose was the highest followed by fructose, glucose, stachyose, raffinose and myo-inositol, respectively. Phytic acid was predominant organic acid in all varieties, followed by malic acid. Independent of the variety, hazelnuts were rich in pantothenic acid, nicotinic acid, pyridoxal, biotin, thiamine, nicotinamide. Pantothenic and nicotinic acid were significantly higher in most of the varieties in harvest year 2014. Potassium was the most predominant mineral, followed by magnesium, calcium, sodium, manganese, zinc, iron and copper, respectively.

  5. Hierarchical matrices algorithms and analysis

    CERN Document Server

    Hackbusch, Wolfgang

    2015-01-01

    This self-contained monograph presents matrix algorithms and their analysis. The new technique enables not only the solution of linear systems but also the approximation of matrix functions, e.g., the matrix exponential. Other applications include the solution of matrix equations, e.g., the Lyapunov or Riccati equation. The required mathematical background can be found in the appendix. The numerical treatment of fully populated large-scale matrices is usually rather costly. However, the technique of hierarchical matrices makes it possible to store matrices and to perform matrix operations approximately with almost linear cost and a controllable degree of approximation error. For important classes of matrices, the computational cost increases only logarithmically with the approximation error. The operations provided include the matrix inversion and LU decomposition. Since large-scale linear algebra problems are standard in scientific computing, the subject of hierarchical matrices is of interest to scientists ...

  6. Intrinsic character of Stokes matrices

    Science.gov (United States)

    Gagnon, Jean-François; Rousseau, Christiane

    2017-02-01

    Two germs of linear analytic differential systems x k + 1Y‧ = A (x) Y with a non-resonant irregular singularity are analytically equivalent if and only if they have the same eigenvalues and equivalent collections of Stokes matrices. The Stokes matrices are the transition matrices between sectors on which the system is analytically equivalent to its formal normal form. Each sector contains exactly one separating ray for each pair of eigenvalues. A rotation in S allows supposing that R+ lies in the intersection of two sectors. Reordering of the coordinates of Y allows ordering the real parts of the eigenvalues, thus yielding triangular Stokes matrices. However, the choice of the rotation in x is not canonical. In this paper we establish how the collection of Stokes matrices depends on this rotation, and hence on a chosen order of the projection of the eigenvalues on a line through the origin.

  7. Near-field solubility studies

    International Nuclear Information System (INIS)

    Thomason, H.P.; Williams, S.J.

    1992-02-01

    Experimental determinations of the solubilities of americium, plutonium, neptunium, protactinium, thorium, radium, lead, tin, palladium and zirconium are reported. These elements have radioactive isotopes of concern in assessments of radioactive waste disposal. All measurements were made under the highly alkaline conditions typical of the near field of a radioactive waste repository which uses cementitious materials for many of the immobilisation matrices, the backfill and the engineered structures. Low redox potentials, typical of those resulting from the corrosion of iron and steel, were simulated for those elements having more than one accessible oxidation state. The dissolved concentrations of the elements were defined using ultrafiltration. In addition, the corrosion of iron and stainless steel was shown to generate low redox potentials in solution and the solubility of iron(II) at high pH was measured and found to be sufficient for it to act as a redox buffer with respect to neptunium and plutonium. (author)

  8. Soluble porphyrin polymers

    Science.gov (United States)

    Gust, Jr., John Devens; Liddell, Paul Anthony

    2015-07-07

    Porphyrin polymers of Structure 1, where n is an integer (e.g., 1, 2, 3, 4, 5, or greater) ##STR00001## are synthesized by the method shown in FIGS. 2A and 2B. The porphyrin polymers of Structure 1 are soluble in organic solvents such as 2-MeTHF and the like, and can be synthesized in bulk (i.e., in processes other than electropolymerization). These porphyrin polymers have long excited state lifetimes, making the material suitable as an organic semiconductor for organic electronic devices including transistors and memories, as well as solar cells, sensors, light-emitting devices, and other opto-electronic devices.

  9. Tritium metrology within different media: focus on organically bound tritium (OBT); Metrologie du tritium dans differentes matrices: cas du tritium organiquement lie (TOL)

    Energy Technology Data Exchange (ETDEWEB)

    Baglan, N. [CEA Bruyeres-le-Chatel, DIF, 91 (France); Ansoborlo, E. [CEA Marcoule, DEN/DRCP/CETAMA, 30 (France); Cossonnet, C. [IRSN, DEI/STEME/LMRE, 91 - Orsay (France); Fouhal, L. [CEA Cadarache, DEN/D2S/LANSE, 13 - Saint-Paul-lez-Durance (France); Deniau, I.; Mokili, M. [SUBATECH/IN2P3/CNRS, 44 - Nantes (France); Henry, A. [AREVA-NC/DQSSE/PR - La Hague, 50 - Beaumont-Hague, (France); Fourre, E. [CEA Saclay, DSM/DRECAM/LSCE, 91 - Gif-sur-Yvette (France); Olivier, A. [GEA-Marine nationale, 50 - Cherbourg (France)

    2010-07-15

    The measurement of tritium in its various forms (mainly gas (HT), water (HTO) or solid (hydrides)), is an important key step for evaluating health and environmental risks and finally, dosimetry assessment. In vegetable or animal samples, tritium is often associated with the free water fraction, but may be included in the organic form as organically bound tritium (OBT). In this case, 2 forms exist: (i) a fraction called exchangeable or labile (E-OBT), bound to oxygen and nitrogen atoms, and (ii) a so-called non-exchangeable fraction (NE-OBT) bound to carbon atoms. The main technique for tritium analysis is liquid scintillation, which enables one to measure concentrations in the range of several Bq.L{sup -1}. The standards (AFNOR, ISO) published to date relate only to tritium analysis in water. Only one CETAMA method addresses OBT analysis in biological environments. This method has been tested since 2001 through intercomparison circuits on grass samples collected from the environment. Regarding tritium analysis in water, the strengths are reliability of this analysis at low concentrations (order of Bq.L{sup -1}), robustness and simplicity, and weaknesses are linked to problems of background, conservation and contamination of samples. Concerning OBT analysis, the analysis is reliable for values around 50 Bq.kg{sup -1} of fresh sample. The weaknesses are problems of contamination, reproducibility, analysis time (2 to 6 days) and lack of reference materials. The difficulty to date is the separation between E-OBT and NE-OBT, that will need experimental validation. (authors)

  10. Differences in fluorescence characteristics and bioavailability of water-soluble organic matter (WSOM) in sediments and suspended solids in Lihu Lake, China.

    Science.gov (United States)

    Wang, Wenwen; Wang, Shuhang; Jiang, Xia; Zheng, Binghui; Zhao, Li; Zhang, Bo; Chen, Junyi

    2018-05-01

    The spectral characteristics, spatial distribution, and bioavailability of water-soluble organic matter (WSOM) in suspended solids and surface sediments of Lihu Lake, China, were investigated through excitation-emission matrix spectra and parallel factor analysis. The average content of dissolved organic carbon (DOC) in the sediments reached 643.28 ± 58.34 mg C/kg and that in suspended solids was 714.87 ± 69.24 mg C/kg. The fluorescence intensity of WSOM totaled 90.87 ± 5.65 and 115.42 ± 8.02 RU/g for the sediments and suspended solids, respectively. The DOC and fluorescence intensity of the WSOM showed an increasing trend moving from the west to the east of the lake. The WSOM in sediments and suspended solids contained two humic-like (C1 and C2) and one tryptophan-like (C3) components. These components had different fluorescent peaks and relative proportions. In the sediments, the relative proportions of C1, C2, and C3 were 33.71% ± 0.71, 26.83% ± 0.68, and 39.50% ± 0.71%, respectively. Meanwhile, C1 (35.77 ± 0.84%), C2 (34.07 ± 0.61%), and C3 (30.16 ± 0.75%) had similar relative percentages in suspended solids. The sediments had a lower humification index (3.02 ± 0.08) than the suspended solids (4.04 ± 0.15). Exchangeable nitrogen for the sediments and suspended solids was dominated by exchangeable ammonium nitrogen and soluble organic nitrogen, respectively. WSOM plays an important role in migration and transformation of nitrogen in sediments and suspended solids. The sediment-derived WSOM exhibited higher lability and biological activity than did the suspended solid-derived WSOM. The relative ratio of the intensity of protein-like fluorescent component to that of the humic-like one can be used as a reference index to evaluate the lability and biological activity of WSOM in sediments and suspended solids.

  11. Seasonal variability of carbon in humic-like matter of ambient size-segregated water soluble organic aerosols from urban background environment

    Science.gov (United States)

    Frka, Sanja; Grgić, Irena; Turšič, Janja; Gini, Maria I.; Eleftheriadis, Konstantinos

    2018-01-01

    Long-term measurements of carbon in HUmic-LIke Substances (HULIS-C) of ambient size-segregated water soluble organic aerosols were performed using a ten-stage low-pressure Berner impactor from December 2014 to November 2015 at an urban background environment in Ljubljana, Slovenia. The mass size distribution patterns of measured species (PM - particulate matter, WSOC - water-soluble organic carbon and HULIS-C) for all seasons were generally tri-modal (primarily accumulation mode) but with significant seasonal variability. HULIS-C was found to have similar distributions as WSOC, with nearly the same mass median aerodynamic diameters (MMADs), except for winter when the HULIS-C size distribution was bimodal. In autumn and winter, the dominant accumulation mode with MMAD at ca. 0.65 μm contributed 83 and 97% to the total HULIS-C concentration, respectively. HULIS-C accounted for a large fraction of WSOC, averaging more than 50% in autumn and 40% in winter. Alternatively, during warmer periods the contributions of ultrafine (27% in summer) and coarse mode (27% in spring) were also substantial. Based on mass size distribution characteristics, HULIS-C was found to be of various sources. In colder seasons, wood burning was confirmed as the most important HULIS source; secondary formation in atmospheric liquid water also contributed significantly, as revealed by the MMADs of the accumulation mode shifting to larger sizes. The distinct difference between the spring and summer ratios of HULIS-C/WSOC in fine particles (ca. 50% in spring, but only 10% in summer) indicated different sources and chemical composition of WSOC in summer (e.g., SOA formation from biogenic volatile organic compounds (BVOCs) via photochemistry). The enlarged amount of HULIS-C in the ultrafine mode in summer suggests that the important contribution was most likely from new particle formation during higher emissions of BVOC due to the vicinity of a mixed deciduous forest; the higher contribution of

  12. Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Stanford, Lateefah A; Kim, Sunghwan; Klein, Geoffrey C; Smith, Donald F; Rodgers, Ryan P; Marshall, Alan G

    2007-04-15

    We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2.

  13. Recent advances in transport of water-soluble vitamins in organs of the digestive system: a focus on the colon and the pancreas.

    Science.gov (United States)

    Said, Hamid M

    2013-11-01

    This review focuses on recent advances in our understanding of the mechanisms and regulation of water-soluble vitamin (WSV) transport in the large intestine and pancreas, two important organs of the digestive system that have only recently received their fair share of attention. WSV, a group of structurally unrelated compounds, are essential for normal cell function and development and, thus, for overall health and survival of the organism. Humans cannot synthesize WSV endogenously; rather, WSV are obtained from exogenous sources via intestinal absorption. The intestine is exposed to two sources of WSV: a dietary source and a bacterial source (i.e., WSV generated by the large intestinal microbiota). Contribution of the latter source to human nutrition/health has been a subject of debate and doubt, mostly based on the absence of specialized systems for efficient uptake of WSV in the large intestine. However, recent studies utilizing a variety of human and animal colon preparations clearly demonstrate that such systems do exist in the large intestine. This has provided strong support for the idea that the microbiota-generated WSV are of nutritional value to the host, and especially to the nutritional needs of the local colonocytes and their health. In the pancreas, WSV are essential for normal metabolic activities of all its cell types and for its exocrine and endocrine functions. Significant progress has also been made in understanding the mechanisms involved in the uptake of WSV and the effect of chronic alcohol exposure on the uptake processes.

  14. Introduction to random matrices theory and practice

    CERN Document Server

    Livan, Giacomo; Vivo, Pierpaolo

    2018-01-01

    Modern developments of Random Matrix Theory as well as pedagogical approaches to the standard core of the discipline are surprisingly hard to find in a well-organized, readable and user-friendly fashion. This slim and agile book, written in a pedagogical and hands-on style, without sacrificing formal rigor fills this gap. It brings Ph.D. students in Physics, as well as more senior practitioners, through the standard tools and results on random matrices, with an eye on most recent developments that are not usually covered in introductory texts. The focus is mainly on random matrices with real spectrum. The main guiding threads throughout the book are the Gaussian Ensembles. In particular, Wigner’s semicircle law is derived multiple times to illustrate several techniques  (e.g., Coulomb gas approach, replica theory). Most chapters are accompanied by Matlab codes (stored in an online repository) to guide readers through the numerical check of most analytical results.

  15. Community Detection for Correlation Matrices

    Directory of Open Access Journals (Sweden)

    Mel MacMahon

    2015-04-01

    Full Text Available A challenging problem in the study of complex systems is that of resolving, without prior information, the emergent, mesoscopic organization determined by groups of units whose dynamical activity is more strongly correlated internally than with the rest of the system. The existing techniques to filter correlations are not explicitly oriented towards identifying such modules and can suffer from an unavoidable information loss. A promising alternative is that of employing community detection techniques developed in network theory. Unfortunately, this approach has focused predominantly on replacing network data with correlation matrices, a procedure that we show to be intrinsically biased because of its inconsistency with the null hypotheses underlying the existing algorithms. Here, we introduce, via a consistent redefinition of null models based on random matrix theory, the appropriate correlation-based counterparts of the most popular community detection techniques. Our methods can filter out both unit-specific noise and system-wide dependencies, and the resulting communities are internally correlated and mutually anticorrelated. We also implement multiresolution and multifrequency approaches revealing hierarchically nested subcommunities with “hard” cores and “soft” peripheries. We apply our techniques to several financial time series and identify mesoscopic groups of stocks which are irreducible to a standard, sectorial taxonomy; detect “soft stocks” that alternate between communities; and discuss implications for portfolio optimization and risk management.

  16. Community Detection for Correlation Matrices

    Science.gov (United States)

    MacMahon, Mel; Garlaschelli, Diego

    2015-04-01

    A challenging problem in the study of complex systems is that of resolving, without prior information, the emergent, mesoscopic organization determined by groups of units whose dynamical activity is more strongly correlated internally than with the rest of the system. The existing techniques to filter correlations are not explicitly oriented towards identifying such modules and can suffer from an unavoidable information loss. A promising alternative is that of employing community detection techniques developed in network theory. Unfortunately, this approach has focused predominantly on replacing network data with correlation matrices, a procedure that we show to be intrinsically biased because of its inconsistency with the null hypotheses underlying the existing algorithms. Here, we introduce, via a consistent redefinition of null models based on random matrix theory, the appropriate correlation-based counterparts of the most popular community detection techniques. Our methods can filter out both unit-specific noise and system-wide dependencies, and the resulting communities are internally correlated and mutually anticorrelated. We also implement multiresolution and multifrequency approaches revealing hierarchically nested subcommunities with "hard" cores and "soft" peripheries. We apply our techniques to several financial time series and identify mesoscopic groups of stocks which are irreducible to a standard, sectorial taxonomy; detect "soft stocks" that alternate between communities; and discuss implications for portfolio optimization and risk management.

  17. Special matrices of mathematical physics stochastic, circulant and Bell matrices

    CERN Document Server

    Aldrovandi, R

    2001-01-01

    This book expounds three special kinds of matrices that are of physical interest, centering on physical examples. Stochastic matrices describe dynamical systems of many different types, involving (or not) phenomena like transience, dissipation, ergodicity, nonequilibrium, and hypersensitivity to initial conditions. The main characteristic is growth by agglomeration, as in glass formation. Circulants are the building blocks of elementary Fourier analysis and provide a natural gateway to quantum mechanics and noncommutative geometry. Bell polynomials offer closed expressions for many formulas co

  18. [Characterizing chromophoric dissolved organic matter (CDOM) in Lake Honghu, Lake Donghu and Lake Liangzihu using excitation-emission matrices (EEMs) fluorescence and parallel factor analysis (PARAFAC)].

    Science.gov (United States)

    Zhou, Yong-Qiang; Zhang, Yun-Lin; Niu, Cheng; Wang, Ming-Zhu

    2013-12-01

    Little is known about DOM characteristics in medium to large sized lakes located in the middle and lower reaches of Yangtze River, like Lake Honghu, Lake Donghu and Lake Liangzihu. Absorption, fluorescence and composition characteristics of chromophoric dissolved organic matter (CDOM) are presented using the absorption spectroscopy, the excitation-emission ma trices (EEMs) fluorescence and parallel factor analysis (PARAFAC) model based on the data collected in Sep-Oct. 2007 including 15, 9 and 10 samplings in Lake Honghu, Lake Donghu and Lake Liangzihu, respectively. CDOM absorption coefficient at 350 nm a(350) coefficient in Lake Honghu was significantly higher than those in Lake Donghu and Lake Liangzihu (t-test, pCDOM spectral slope in the wavelength range of 280-500 nm (S280-500) and a(350) (R2 =0. 781, p<0. 001). The mean value of S280-500 in Lake Honghu was significantly lower than those in Lake Donghu (t-test, p

  19. New pyrolytic and spectroscopic data on Orgueil and Murchison insoluble organic matter: A different origin than soluble?

    Science.gov (United States)

    Remusat, Laurent; Derenne, Sylvie; Robert, François; Knicker, Heike

    2005-08-01

    Pyrolysis with and without tetramethylammonium hydroxide (TMAH), vacuum pyrolysis, and solid state 15N nuclear magnetic resonance (NMR) were used to examine the macromolecular insoluble organic matter (IOM) from the Orgueil and Murchison meteorites. Conventional pyrolysis reveals a set of poorly functionalized aromatic compounds, ranging from one to four rings and with random methyl substitutions. These compounds are in agreement with spectroscopic and pyrolytic results previously reported. For the first time, TMAH thermochemolysis was used to study extraterrestrial material. The detection of aromatics bearing methyl esters and methoxy groups reveals the occurrence of ester and ether bridges between aromatic units in the macromolecular network. No nitrogen-containing compounds were detected with TMAH thermochemolysis, although they are a common feature in terrestrial samples. Along with vacuum pyrolysis results, thermochemolysis shows that nitrogen is probably sequestered in condensed structures like heterocyclic aromatic rings, unlike oxygen, which is mainly located within linkages between aromatic units. This is confirmed by solid state 15N NMR performed on IOM from Orgueil, showing that nitrogen is present in pyrrole, indole, and carbazole moieties. These data show that amino acids are neither derived from the hydrolysis of IOM nor from a common precursor. In order to reconcile the literature isotopic data and the present molecular results, it is proposed that aldehydes and ketones (1) originated during irradiation of ice in space and (2) were then mobilized during the planetesimal hydrothermalism, yielding the formation of amino acids. If correct, prebiotic molecules are the products of the subsurface chemistry of planetesimals and are thus undetectable through astronomical probes.

  20. The invariant theory of matrices

    CERN Document Server

    Concini, Corrado De

    2017-01-01

    This book gives a unified, complete, and self-contained exposition of the main algebraic theorems of invariant theory for matrices in a characteristic free approach. More precisely, it contains the description of polynomial functions in several variables on the set of m\\times m matrices with coefficients in an infinite field or even the ring of integers, invariant under simultaneous conjugation. Following Hermann Weyl's classical approach, the ring of invariants is described by formulating and proving the first fundamental theorem that describes a set of generators in the ring of invariants, and the second fundamental theorem that describes relations between these generators. The authors study both the case of matrices over a field of characteristic 0 and the case of matrices over a field of positive characteristic. While the case of characteristic 0 can be treated following a classical approach, the case of positive characteristic (developed by Donkin and Zubkov) is much harder. A presentation of this case...

  1. Quantum matrices in two dimensions

    International Nuclear Information System (INIS)

    Ewen, H.; Ogievetsky, O.; Wess, J.

    1991-01-01

    Quantum matrices in two-dimensions, admitting left and right quantum spaces, are classified: they fall into two families, the 2-parametric family GL p,q (2) and a 1-parametric family GL α J (2). Phenomena previously found for GL p,q (2) hold in this general situation: (a) powers of quantum matrices are again quantum and (b) entries of the logarithm of a two-dimensional quantum matrix form a Lie algebra. (orig.)

  2. Designer matrices for intestinal stem cell and organoid culture

    NARCIS (Netherlands)

    Gjorevski, Nikolce; Sachs, Norman; Manfrin, Andrea; Giger, Sonja; Bragina, Maiia E.; Ordóñez-Morán, Paloma; Clevers, Hans; Lutolf, Matthias P.

    2016-01-01

    Epithelial organoids recapitulate multiple aspects of real organs, making them promising models of organ development, function and disease. However, the full potential of organoids in research and therapy has remained unrealized, owing to the poorly defined animal-derived matrices in which they are

  3. Manin matrices and Talalaev's formula

    International Nuclear Information System (INIS)

    Chervov, A; Falqui, G

    2008-01-01

    In this paper we study properties of Lax and transfer matrices associated with quantum integrable systems. Our point of view stems from the fact that their elements satisfy special commutation properties, considered by Yu I Manin some 20 years ago at the beginning of quantum group theory. These are the commutation properties of matrix elements of linear homomorphisms between polynomial rings; more explicitly these read: (1) elements of the same column commute; (2) commutators of the cross terms are equal: [M ij , M kl ] [M kj , M il ] (e.g. [M 11 , M 22 ] = [M 21 , M 12 ]). The main aim of this paper is twofold: on the one hand we observe and prove that such matrices (which we call Manin matrices in short) behave almost as well as matrices with commutative elements. Namely, the theorems of linear algebra (e.g., a natural definition of the determinant, the Cayley-Hamilton theorem, the Newton identities and so on and so forth) have a straightforward counterpart in the case of Manin matrices. On the other hand, we remark that such matrices are somewhat ubiquitous in the theory of quantum integrability. For instance, Manin matrices (and their q-analogs) include matrices satisfying the Yang-Baxter relation 'RTT=TTR' and the so-called Cartier-Foata matrices. Also, they enter Talalaev's remarkable formulae: det(∂ z -L gaudin (z)), det(1-e -∂z T Yangian (z)) for the 'quantum spectral curve', and appear in the separation of variables problem and Capelli identities. We show that theorems of linear algebra, after being established for such matrices, have various applications to quantum integrable systems and Lie algebras, e.g. in the construction of new generators in Z(U crit (gl-hat n )) (and, in general, in the construction of quantum conservation laws), in the Knizhnik-Zamolodchikov equation, and in the problem of Wick ordering. We propose, in the appendix, a construction of quantum separated variables for the XXX-Heisenberg system

  4. Technical Note: Molecular characterization of aerosol-derived water soluble organic carbon using ultrahigh resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

    Directory of Open Access Journals (Sweden)

    R. M. Dickhut

    2008-09-01

    Full Text Available Despite the acknowledged relevance of aerosol-derived water-soluble organic carbon (WSOC to climate and biogeochemical cycling, characterization of aerosol WSOC has been limited. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS was utilized in this study to provide detailed molecular level characterization of the high molecular weight (HMW; m/z>223 component of aerosol-derived WSOC collected from rural sites in Virginia and New York, USA. More than 3000 peaks were detected by ESI FT-ICR MS within a m/z range of 223–600 for each sample. Approximately 86% (Virginia and 78% (New York of these peaks were assigned molecular formulas using only carbon (C, hydrogen (H, oxygen (O, nitrogen (N, and sulfur (S as elemental constituents. H/C and O/C molar ratios were plotted on van Krevelen diagrams and indicated a strong contribution of lignin-like and lipid-like compounds to the aerosol-derived WSOC samples. Approximately 1–4% of the peaks in the aerosol-derived WSOC mass spectra were classified as black carbon (BC on the basis of double bond equivalents calculated from the assigned molecular formulas. In addition, several high-magnitude peaks in the mass spectra of samples from both sites corresponded to molecular formulas proposed in previous secondary organic aerosol (SOA laboratory investigations indicating that SOAs are important constituents of the WSOC. Overall, ESI FT-ICR MS provides a level of resolution adequate for detailed compositional and source information of the HMW constituents of aerosol-derived WSOC.

  5. On reflectionless equi-transmitting matrices

    Directory of Open Access Journals (Sweden)

    Pavel Kurasov

    2014-01-01

    Full Text Available Reflectionless equi-transmitting unitary matrices are studied in connection to matching conditions in quantum graphs. All possible such matrices of size 6 are described explicitly. It is shown that such matrices form 30 six-parameter families intersected along 12 five-parameter families closely connected to conference matrices.

  6. Spectra of sparse random matrices

    International Nuclear Information System (INIS)

    Kuehn, Reimer

    2008-01-01

    We compute the spectral density for ensembles of sparse symmetric random matrices using replica. Our formulation of the replica-symmetric ansatz shares the symmetries of that suggested in a seminal paper by Rodgers and Bray (symmetry with respect to permutation of replica and rotation symmetry in the space of replica), but uses a different representation in terms of superpositions of Gaussians. It gives rise to a pair of integral equations which can be solved by a stochastic population-dynamics algorithm. Remarkably our representation allows us to identify pure-point contributions to the spectral density related to the existence of normalizable eigenstates. Our approach is not restricted to matrices defined on graphs with Poissonian degree distribution. Matrices defined on regular random graphs or on scale-free graphs, are easily handled. We also look at matrices with row constraints such as discrete graph Laplacians. Our approach naturally allows us to unfold the total density of states into contributions coming from vertices of different local coordinations and an example of such an unfolding is presented. Our results are well corroborated by numerical diagonalization studies of large finite random matrices

  7. Free probability and random matrices

    CERN Document Server

    Mingo, James A

    2017-01-01

    This volume opens the world of free probability to a wide variety of readers. From its roots in the theory of operator algebras, free probability has intertwined with non-crossing partitions, random matrices, applications in wireless communications, representation theory of large groups, quantum groups, the invariant subspace problem, large deviations, subfactors, and beyond. This book puts a special emphasis on the relation of free probability to random matrices, but also touches upon the operator algebraic, combinatorial, and analytic aspects of the theory. The book serves as a combination textbook/research monograph, with self-contained chapters, exercises scattered throughout the text, and coverage of important ongoing progress of the theory. It will appeal to graduate students and all mathematicians interested in random matrices and free probability from the point of view of operator algebras, combinatorics, analytic functions, or applications in engineering and statistical physics.

  8. Chequered surfaces and complex matrices

    International Nuclear Information System (INIS)

    Morris, T.R.; Southampton Univ.

    1991-01-01

    We investigate a large-N matrix model involving general complex matrices. It can be reinterpreted as a model of two hermitian matrices with specific couplings, and as a model of positive definite hermitian matrices. Large-N perturbation theory generates dynamical triangulations in which the triangles can be chequered (i.e. coloured so that neighbours are opposite colours). On a sphere there is a simple relation between such triangulations and those generated by the single hermitian matrix model. For the torus (and a quartic potential) we solve the counting problem for the number of triangulations that cannot be quechered. The critical physics of chequered triangulations is the same as that of the hermitian matrix model. We show this explicitly by solving non-perturbatively pure two-dimensional ''chequered'' gravity. The interpretative framework given here applies to a number of other generalisations of the hermitian matrix model. (orig.)

  9. [Soil soluble organic matter, microbial biomass, and enzyme activities in forest plantations in degraded red soil region of Jiangxi Province, China].

    Science.gov (United States)

    Jiang, Yu-mei; Chen, Cheng-long; Xu, Zhi-hong; Liu, Yuan-qiu; Ouyang, Jing; Wang, Fang

    2010-09-01

    Taking the adjacent 18-year-old pure Pinus massoniana pure forest (I), P. massoniana, Liquidamber fomosana, and Schima superba mixed forest (II), S. superba pure forest (III), L. fomosana (IV) pure forest, and natural restoration fallow land (CK) in Taihe County of Jiangxi Province as test sites, a comparative study was made on their soil soluble organic carbon (SOC) and nitrogen (SON), soil microbial biomass C (MBC) and N (MBN), and soil urease and asparaginase activities. In 0-10 cm soil layer, the pool sizes of SOC, SON, MBC, and MBN at test sites ranged in 354-1007 mg x kg(-1), 24-73 mg x kg(-1), 203-488 mg x kg(-1), and 24-65 mg x kg(-1), and the soil urease and asparaginase activities were 95-133 mg x kg(-1) x d(-1) and 58-113 mg x kg(-1) x d(-1), respectively. There were significant differences in the pool sizes of SOC, SON, MBC, and MBN and the asparaginase activity among the test sites, but no significant difference was observed in the urease activity. The pool sizes of SOC and SON were in the order of IV > CK > III > I > II, those of MBC and MBN were in the order of CK > IV > III > I > II, and asparaginase activity followed the order of IV > CK > III > II > I. With the increase of soil depth, the pool sizes of SOC, SON, MBC, and MBN and the activities of soil asparaginase and urease decreased. In 0-20 cm soil layer, the SOC, SON, MBC, MBN, total C, and total N were highly correlated with each other, soil asparaginase activity was highly correlated with SOC, SON, TSN, total C, total N, MBC, and MBN, and soil urease activity was highly correlated with SON, TSN, total C, MBC and MBN.

  10. Loop diagrams without γ matrices

    International Nuclear Information System (INIS)

    McKeon, D.G.C.; Rebhan, A.

    1993-01-01

    By using a quantum-mechanical path integral to compute matrix elements of the form left-angle x|exp(-iHt)|y right-angle, radiative corrections in quantum-field theory can be evaluated without encountering loop-momentum integrals. In this paper we demonstrate how Dirac γ matrices that occur in the proper-time ''Hamiltonian'' H lead to the introduction of a quantum-mechanical path integral corresponding to a superparticle analogous to one proposed recently by Fradkin and Gitman. Direct evaluation of this path integral circumvents many of the usual algebraic manipulations of γ matrices in the computation of quantum-field-theoretical Green's functions involving fermions

  11. Immanant Conversion on Symmetric Matrices

    Directory of Open Access Journals (Sweden)

    Purificação Coelho M.

    2014-01-01

    Full Text Available Letr Σn(C denote the space of all n χ n symmetric matrices over the complex field C. The main objective of this paper is to prove that the maps Φ : Σn(C -> Σn (C satisfying for any fixed irre- ducible characters X, X' -SC the condition dx(A +aB = dχ·(Φ(Α + αΦ(Β for all matrices A,В ε Σ„(С and all scalars a ε C are automatically linear and bijective. As a corollary of the above result we characterize all such maps Φ acting on ΣИ(С.

  12. Spectroscopy, modeling and computation of metal chelate solubility in supercritical CO2

    International Nuclear Information System (INIS)

    Brennecke, J.F.; Stadtherr, M.A.

    1999-01-01

    The overall objectives of this project were to gain a fundamental understanding of the solubility and phase behavior of metal chelates in supercritical CO 2 . Extraction with CO 2 is an excellent way to remove organic compounds from soils, sludges and aqueous solutions, and recent research has demonstrated that, together with chelating agents, it is a viable way to remove metals, as well. In this project the authors sought to gain fundamental knowledge that is vital to computing phase behavior, and modeling and designing processes using CO 2 to separate organics and metal compounds from DOE mixed wastes. The overall program was a comprehensive one to measure, model and compute the solubility of metal chelate complexes in supercritical CO 2 and CO 2 /cosolvent mixtures. Through a combination of phase behavior measurements, spectroscopy and the development of a new computational technique, the authors have achieved a completely reliable way to model metal chelate solubility in supercritical CO 2 and CO 2 /co-contaminant mixtures. Thus, they can now design and optimize processes to extract metals from solid matrices using supercritical CO 2 , as an alternative to hazardous organic solvents that create their own environmental problems, even while helping in metals decontamination

  13. A Combined Study Investigating the Insoluble and Soluble Organic Compounds in Category 3 Carbonaceous Itokawa Particles Recovered by the Hayabusa Mission

    Science.gov (United States)

    Chan, Q. H. S.; Zolensky, M.; Burton, A.; Clemett, S.; Fries, M.; Kebukawa, Y.

    2015-01-01

    At the 3rd International Announcement of Opportunity (AO), we have been approved for five Category 3 carbonaceous Itokawa particles (RA-QD02-0012, RA-QD02-0078, RB-CV-0029, RB-CV-0080 and RB-QD04-0052) recovered by the first Hayabusa mission of JAXA. In this investigation, we aim to provide a comprehensive study to characterize and account for the presence of carbon-bearing phases as suggested by the initial Scanning Electron Microscopy (SEM) analysis carried out by JAXA at the curation facility, and to describe the mineralogical components of the particles. The insoluble organic content of Itokawa particle has been investigated with the use of micro-Raman spectroscopy by Kitajima and co-workers [1]. The Raman spectra of Itokawa particles show broad G- and D-bands typical of low temperature material which offers an interesting contrast to the high metamorphic grade (LL4-6) of the Itokawa parent body. Amino acid analysis has been conducted by Naraoka et al. [2] to study the soluble organic component of Itokawa particles, but since it was a preliminary study and thus did not have the opportunity to target on Category 3 carbonaceous particles, only terrestrial contaminants were identified. The investigation will be carried out in the following order prioritized according to the progressive damage the analytical techniques can induce: (1) micro-Raman spectrometry, (2) two-step laser mass spectrometry (micro-L2MS), (3) ultra-high performance liquid chromatography with fluorescence detection and time-of-flight mass spectrometry (LC-FD/ToF-MS), and optimally if we can recover the particles after wet chemistry analysis, we will mount the samples and perform (4) electron beam microscopy (SEM, electron back-scattered diffraction [EBSD]) and (5) carbon X-ray absorption near edge structure spectroscopy (C-XANES). We will begin the analytical procedures upon receiving the samples in September/October. This work will provide us with an understanding of the variety and origins of

  14. The search for reliable aqueous solubility (Sw) and octanol-water partition coefficient (Kow) data for hydrophobic organic compounds; DDT and DDE as a case study

    Science.gov (United States)

    Pontolillo, James; Eganhouse, R.P.

    2001-01-01

    The accurate determination of an organic contaminant?s physico-chemical properties is essential for predicting its environmental impact and fate. Approximately 700 publications (1944?2001) were reviewed and all known aqueous solubilities (Sw) and octanol-water partition coefficients (Kow) for the organochlorine pesticide, DDT, and its persistent metabolite, DDE were compiled and examined. Two problems are evident with the available database: 1) egregious errors in reporting data and references, and 2) poor data quality and/or inadequate documentation of procedures. The published literature (particularly the collative literature such as compilation articles and handbooks) is characterized by a preponderance of unnecessary data duplication. Numerous data and citation errors are also present in the literature. The percentage of original Sw and Kow data in compilations has decreased with time, and in the most recent publications (1994?97) it composes only 6?26 percent of the reported data. The variability of original DDT/DDE Sw and Kow data spans 2?4 orders of magnitude, and there is little indication that the uncertainty in these properties has declined over the last 5 decades. A criteria-based evaluation of DDT/DDE Sw and Kow data sources shows that 95?100 percent of the database literature is of poor or unevaluatable quality. The accuracy and reliability of the vast majority of the data are unknown due to inadequate documentation of the methods of determination used by the authors. [For example, estimates of precision have been reported for only 20 percent of experimental Sw data and 10 percent of experimental Kow data.] Computational methods for estimating these parameters have been increasingly substituted for direct or indirect experimental determination despite the fact that the data used for model development and validation may be of unknown reliability. Because of the prevalence of errors, the lack of methodological documentation, and unsatisfactory data

  15. Innovative Immobilization Matrices.

    Science.gov (United States)

    Alvarez, Gisela S; Echazu, Maria I A; Bertinatto, Jessica A; Catalano, Paolo N; Copello, Guillermo J; Foglia, Maria L; Gonzalez, Joaquin A; Giorgieri, Sergio A; Iglesias, Silvia L; Mebert, Andrea M; Santo-Orihuela, Pablo L; Tuttolomondo, Maria V; Villanueva, Emilia E; Desimone, Martín F

    2016-01-01

    We present a brief survey of some of the recent work of Professor Luis E. Díaz, performed together with his students and collaborators at the University of Buenos Aires. Dr Luis E. Díaz has been involved in research on biochemical and pharmaceutical sciences solving scientific and industry problems for over 40 years until he passed away. Prof. Díaz scientific interests included various topics from NMR spectroscopy to biomedicine but fundamentally he focused in various aspects of chemistry (analytical, organic, inorganic and environmental). This is not a complete survey but a sampling of prominent projects related to sol-gel chemistry with a focus on some of his recent publications.

  16. On families of anticommuting matrices

    Czech Academy of Sciences Publication Activity Database

    Hrubeš, Pavel

    2016-01-01

    Roč. 493, March 15 (2016), s. 494-507 ISSN 0024-3795 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : anticommuting matrices * sum-of-squares formulas Subject RIV: BA - General Mathematics Impact factor: 0.973, year: 2016 http://www.sciencedirect.com/science/article/pii/S0024379515007296

  17. On families of anticommuting matrices

    Czech Academy of Sciences Publication Activity Database

    Hrubeš, Pavel

    2016-01-01

    Roč. 493, March 15 (2016), s. 494-507 ISSN 0024-3795 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : anticommuting matrices * sum -of-squares formulas Subject RIV: BA - General Mathematics Impact factor: 0.973, year: 2016 http://www.sciencedirect.com/science/article/pii/S0024379515007296

  18. MALDI matrices for low molecular weight compounds: an endless story?

    Science.gov (United States)

    Calvano, Cosima Damiana; Monopoli, Antonio; Cataldi, Tommaso R I; Palmisano, Francesco

    2018-04-23

    Since its introduction in the 1980s, matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) has gained a prominent role in the analysis of high molecular weight biomolecules such as proteins, peptides, oligonucleotides, and polysaccharides. Its application to low molecular weight compounds has remained for long time challenging due to the spectral interferences produced by conventional organic matrices in the low m/z window. To overcome this problem, specific sample preparation such as analyte/matrix derivatization, addition of dopants, or sophisticated deposition technique especially useful for imaging experiments, have been proposed. Alternative approaches based on second generation (rationally designed) organic matrices, ionic liquids, and inorganic matrices, including metallic nanoparticles, have been the object of intense and continuous research efforts. Definite evidences are now provided that MALDI MS represents a powerful and invaluable analytical tool also for small molecules, including their quantification, thus opening new, exciting applications in metabolomics and imaging mass spectrometry. This review is intended to offer a concise critical overview of the most recent achievements about MALDI matrices capable of specifically address the challenging issue of small molecules analysis. Graphical abstract An ideal Book of matrices for MALDI MS of small molecules.

  19. Water soluble two-photon fluorescent organic probes for long-term imaging of lysosomes in live cells and tumor spheroids.

    Science.gov (United States)

    Kumari, Pratibha; Verma, Sanjay K; Mobin, Shaikh M

    2018-01-11

    The morphological alteration of lysosomes is a powerful indicator of various pathological disorders. In this regard, we have designed and synthesized a new water soluble fluorescent Schiff-base ligand (L-lyso) containing two hydroxyl groups. L-lyso exhibits excellent two-photon properties with tracking of lysosomes in live cells as well as in 3D tumor spheroids. Furthermore, it can label lysosomes for more than 3 days. Thus, L-lyso has an edge over the commercially available expensive LysoTracker probes and also over other reported probes in terms of its long-term imaging, water solubility and facile synthesis.

  20. The modified Gauss diagonalization of polynomial matrices

    International Nuclear Information System (INIS)

    Saeed, K.

    1982-10-01

    The Gauss algorithm for diagonalization of constant matrices is modified for application to polynomial matrices. Due to this modification the diagonal elements become pure polynomials rather than rational functions. (author)

  1. Double stochastic matrices in quantum mechanics

    International Nuclear Information System (INIS)

    Louck, J.D.

    1997-01-01

    The general set of doubly stochastic matrices of order n corresponding to ordinary nonrelativistic quantum mechanical transition probability matrices is given. Lande's discussion of the nonquantal origin of such matrices is noted. Several concrete examples are presented for elementary and composite angular momentum systems with the focus on the unitary symmetry associated with such systems in the spirit of the recent work of Bohr and Ulfbeck. Birkhoff's theorem on doubly stochastic matrices of order n is reformulated in a geometrical language suitable for application to the subset of quantum mechanical doubly stochastic matrices. Specifically, it is shown that the set of points on the unit sphere in cartesian n'-space is subjective with the set of doubly stochastic matrices of order n. The question is raised, but not answered, as to what is the subset of points of this unit sphere that correspond to the quantum mechanical transition probability matrices, and what is the symmetry group of this subset of matrices

  2. Virial expansion for almost diagonal random matrices

    Science.gov (United States)

    Yevtushenko, Oleg; Kravtsov, Vladimir E.

    2003-08-01

    Energy level statistics of Hermitian random matrices hat H with Gaussian independent random entries Higeqj is studied for a generic ensemble of almost diagonal random matrices with langle|Hii|2rangle ~ 1 and langle|Hi\

  3. Phenomenological mass matrices with a democratic warp

    International Nuclear Information System (INIS)

    Kleppe, A.

    2018-01-01

    Taking into account all available data on the mass sector, we obtain unitary rotation matrices that diagonalize the quark matrices by using a specific parametrization of the Cabibbo-Kobayashi-Maskawa mixing matrix. In this way, we find mass matrices for the up- and down-quark sectors of a specific, symmetric form, with traces of a democratic texture.

  4. Aluminum solubility and mobility in relation to organic carbon in surface soils affected by six tree species of the northeastern United States

    NARCIS (Netherlands)

    Dijkstra, F.A.; Fitzhugh, R.D.

    2003-01-01

    We compared Al solubility and mobility in surface soils among six tree species (sugar maple [Acer saccharum], white ash [Fraxinus americana], red maple [Acer rubrum, L.], American beech [Fagus grandifolia, Ehrh.], red oak [Quercus rubra, L.], and hemlock [Tsuga canadensis, Carr.]) in a mixed

  5. Effect of corn processing and wet distiller’s grains with solubles on odorous volatile organic compound emissions from urine and feces of beef cattle

    Science.gov (United States)

    Wet distiller’s grains with solubles (WDGS) are a common feed ingredient in beef feedlot diets, but the excess nitrogen in these diets creates air quality issues, primarily due to the aromatic compounds emitted during fermentation of excreted protein. Use of high-moisture corn (HMC) instead of dry-r...

  6. S-matrices and integrability

    International Nuclear Information System (INIS)

    Bombardelli, Diego

    2016-01-01

    In these notes we review the S-matrix theory in (1+1)-dimensional integrable models, focusing mainly on the relativistic case. Once the main definitions and physical properties are introduced, we discuss the factorization of scattering processes due to integrability. We then focus on the analytic properties of the two-particle scattering amplitude and illustrate the derivation of the S-matrices for all the possible bound states using the so-called bootstrap principle. General algebraic structures underlying the S-matrix theory and its relation with the form factors axioms are briefly mentioned. Finally, we discuss the S-matrices of sine-Gordon and SU (2), SU (3) chiral Gross–Neveu models. (topical review)

  7. Thermodynamic models for determination of the solubility of omeprazole in pure and mixture organic solvents from T = (278.15 to 333.15) K

    International Nuclear Information System (INIS)

    Hu, Yonghong; Wu, Gang; Gu, Pengfei; Yang, Wenge; Wang, Chunxiao; Ding, Zhiwen; Cao, Yang

    2016-01-01

    Highlights: • The solubility increased with increasing temperature. • The data were fitted using the modified Apelblat equation and other models. • The Gibbs energy, enthalpy and entropy were calculated by the van’t Hoff analysis. - Abstract: Data on corresponding (solid + liquid) equilibrium of omeprazole in different solvents are essential for a preliminary study of industrial applications. In this paper, the (solid + liquid) equilibrium of omeprazole in water, methanol, ethanol, 1-butanol, acetonitrile, acetone, ethyl acetate, tetrahydrofuran pure solvents and (tetrahydrofuran + ethyl acetate) mixture solvents were explored within the temperatures from 278.15 K to 333.15 K under atmosphere pressure. For the temperature range investigated, the solubility of omeprazole in the solvents increased with increasing temperature. From (278.15 to 333.15) K, the solubility of omeprazole in tetrahydrofuran is superior to other selected pure solvents. The modified Apelblat model, the Buchowski–Ksiazaczak λh model, and the ideal model were adopted to describe and predict the change tendency of solubility. Computational results showed that the modified Apelblat model has advantages than the other two models. Numerical values of the solubility were fitted using a modified Apelblat equation, a variant of the combined nearly ideal binary solvent/Redich–Kister (CNIBS/R–K) model and Jouyban–Acree model in (tetrahydrofuran + ethyl acetate) binary solvent mixture. Computational results showed that the CNIBS/R–K model is superior to the other equations. In addition, the calculated thermodynamic parameters indicate that in each solvent studied the dissolution of omeprazole is endothermic, non-spontaneous and is an entropy-driven process.

  8. Synthesised standards in natural matrices

    International Nuclear Information System (INIS)

    Olsen, D.G.

    1980-01-01

    The problem of securing the most reliable standards for the accurate analysis of radionuclides is discussed in the paper and in the comment on the paper. It is contended in the paper that the best standards can be created by quantitative addition of accurately known spiking solutions into carefully selected natural matrices. On the other hand it is argued that many natural materials can be successfully standardized for numerous trace constituents. Both points of view are supported with examples. (U.K.)

  9. Gas solubilities widespread applications

    CERN Document Server

    Gerrard, William

    1980-01-01

    Gas Solubilities: Widespread Applications discusses several topics concerning the various applications of gas solubilities. The first chapter of the book reviews Henr's law, while the second chapter covers the effect of temperature on gas solubility. The third chapter discusses the various gases used by Horiuti, and the following chapters evaluate the data on sulfur dioxide, chlorine data, and solubility data for hydrogen sulfide. Chapter 7 concerns itself with solubility of radon, thoron, and actinon. Chapter 8 tackles the solubilities of diborane and the gaseous hydrides of groups IV, V, and

  10. Effect of organic matrices on the determination of the trace element chemistry (Mg, Sr, Mg/Ca, Sr/Ca) of aragonitic bivalve shells (Arctica islandica). Comparison of ICP-OES and LA-ICP-MS data

    International Nuclear Information System (INIS)

    Schoene, Bernd R.; Zhang, Zengjie; Jacob, Dorrit; Soldate, Analia; Gillikin, David P.; Tuetken, Thomas; Garbe-Shoenberg, Dieter; McConnaughey, Ted

    2010-01-01

    The element chemistry of biogenic carbonates can provide important data on past environments. However, the Sr/Ca and Mg/Ca ratios as well as the Mg and Sr concentrations of biological carbonates, especially aragonitic bivalves often depart from apparent thermodynamic equilibrium. When measured in situ by means of LA-ICP-MS, the Mg concentration is often substantially enriched (two- to threefold) near the organic-rich, annual growth lines. To test the hypothesis that some organic components exert a major influence on the skeletal metal content, the element chemistry of different shell components (insoluble organic matrix, IOM; dissolved CaCO 3 and soluble organics, SOM) of Arctica islandica was measured by means of ICP-OES and LA-ICP-MS. The ICP-OES data indicate that the IOM is strongly enriched in Mg (130 ppm) and depleted in Sr and Ca (10 ppm and 0.22 wt%, respectively) when compared to the whole biomineral (Mg: 68 to 99 ppm, Sr: 860 to 1,060 ppm, Ca: ∼35.72 wt%). Although the average relative abundance of the IOM barely exceeds 0.46 wt%, its chemical composition in combination with its heterogeneous distribution across the shell can significantly increase estimates of the Mg concentration if measured in situ by LA-ICP-MS. Depending on the distribution of the IOM, the Ca concentration may be significantly lower locally than the average Ca concentration of the whole shell (35.72 wt%). If this remains undetected, the Mg concentration of shell portions with higher than average IOM content is overestimated by LA-ICP-MS and, conversely, the Mg concentration is underestimated in shell portions with lower than average IOM content. Removal of the IOM prior to the chemical analysis by LA-ICP-MS or mathematical correction for the IOM-derived magnesium concentrations is therefore strongly advised. The different chemistry of the IOM may also exert a major control on the trace element to calcium ratios. Shell portions enriched in IOM will show up to 200 times higher Mg

  11. Evaluating the effectiveness of mulch application to store carbon belowground: Short-term effects of mulch application on soluble soil and microbial C and N in agricultural soils with low and high organic matter

    Science.gov (United States)

    Chen, Janet; Heiling, Maria; Resch, Christian; Gruber, Roman; Dercon, Gerd

    2017-04-01

    Agricultural soils have the potential to contain a large pool of carbon and, depending on the farming techniques applied, can either effectively store carbon belowground, or further release carbon, in the form of CO2, into the atmosphere. Farming techniques, such as mulch application, are frequently proposed to increase carbon content belowground and improve soil quality and can be used in efforts to reduce greenhouse gas levels, such as in the "4 per 1000" Initiative. To test the effectiveness of mulch application to store carbon belowground in the short term and improve soil nutrient quality, we maintained agricultural soils with low and high organic carbon content (disturbed top soil from local Cambisols and Chernozems) in greenhouse mesocosms (70 cm deep with a radius of 25 cm) with controlled moisture for 4 years. Over the 4 years, maize and soybean were grown yearly in rotation and mulch was removed or applied to soils once plant material was harvested at 2 ton/ha dry matter. In addition, soil disturbance was kept to a minimum, with only surface disturbance of a few centimeters to keep soil free from weeds. After 4 years, we measured effects of mulch application on soluble soil and microbial carbon and nitrogen in the mesocosms and compared effects of mulch application versus no mulch on soils from 0-5 cm and 5-15 cm with low and high organic matter. We predicted that mulch would increase soil carbon and nitrogen content and mulch application would have a greater effect on soils with low organic matter than soils with high organic matter. In soils with low organic carbon content and larger predicted potential to increase soil carbon, mulch application did not increase soluble soil or microbial carbon or nitrogen compared to the treatments without mulch application. However, mulch application significantly increased the δ13C of both microbial and soluble soil carbon in these soils by 1 ‰ each, indicating a shift in belowground processes, such as increased

  12. Sparse Matrices in Frame Theory

    DEFF Research Database (Denmark)

    Lemvig, Jakob; Krahmer, Felix; Kutyniok, Gitta

    2014-01-01

    Frame theory is closely intertwined with signal processing through a canon of methodologies for the analysis of signals using (redundant) linear measurements. The canonical dual frame associated with a frame provides a means for reconstruction by a least squares approach, but other dual frames...... yield alternative reconstruction procedures. The novel paradigm of sparsity has recently entered the area of frame theory in various ways. Of those different sparsity perspectives, we will focus on the situations where frames and (not necessarily canonical) dual frames can be written as sparse matrices...

  13. The Inverse of Banded Matrices

    Science.gov (United States)

    2013-01-01

    indexed entries all zeros. In this paper, generalizing a method of Mallik (1999) [5], we give the LU factorization and the inverse of the matrix Br,n (if it...r ≤ i ≤ r, 1 ≤ j ≤ r, with the remaining un-indexed entries all zeros. In this paper generalizing a method of Mallik (1999) [5...matrices and applications to piecewise cubic approximation, J. Comput. Appl. Math. 8 (4) (1982) 285–288. [5] R.K. Mallik , The inverse of a lower

  14. Fusion algebra and fusing matrices

    International Nuclear Information System (INIS)

    Gao Yihong; Li Miao; Yu Ming.

    1989-09-01

    We show that the Wilson line operators in topological field theories form a fusion algebra. In general, the fusion algebra is a relation among the fusing (F) matrices. In the case of the SU(2) WZW model, some special F matrix elements are found in this way, and the remaining F matrix elements are then determined up to a sign. In addition, the S(j) modular transformation of the one point blocks on the torus is worked out. Our results are found to agree with those obtained from the quantum group method. (author). 24 refs

  15. Transfer matrices for multilayer structures

    International Nuclear Information System (INIS)

    Baquero, R.

    1988-08-01

    We consider four of the transfer matrices defined to deal with multilayer structures. We deduce algorithms to calculate them numerically, in a simple and neat way. We illustrate their application to semi-infinite systems using SGFM formulae. These algorithms are of fast convergence and allow a calculation of bulk-, surface- and inner-layers band structure in good agreement with much more sophisticated calculations. Supermatrices, interfaces and multilayer structures can be calculated in this way with a small computational effort. (author). 10 refs

  16. Orthogonal polynomials and random matrices

    CERN Document Server

    Deift, Percy

    2000-01-01

    This volume expands on a set of lectures held at the Courant Institute on Riemann-Hilbert problems, orthogonal polynomials, and random matrix theory. The goal of the course was to prove universality for a variety of statistical quantities arising in the theory of random matrix models. The central question was the following: Why do very general ensembles of random n {\\times} n matrices exhibit universal behavior as n {\\rightarrow} {\\infty}? The main ingredient in the proof is the steepest descent method for oscillatory Riemann-Hilbert problems.

  17. Interactions between Food Additive Silica Nanoparticles and Food Matrices

    Directory of Open Access Journals (Sweden)

    Mi-Ran Go

    2017-06-01

    Full Text Available Nanoparticles (NPs have been widely utilized in the food industry as additives with their beneficial characteristics, such as improving sensory property and processing suitability, enhancing functional and nutritional values, and extending shelf-life of foods. Silica is used as an anti-caking agent to improve flow property of powered ingredients and as a carrier for flavors or active compounds in food. Along with the rapid development of nanotechnology, the sizes of silica fall into nanoscale, thereby raising concerns about the potential toxicity of nano-sized silica materials. There have been a number of studies carried out to investigate possible adverse effects of NPs on the gastrointestinal tract. The interactions between NPs and surrounding food matrices should be also taken into account since the interactions can affect their bioavailability, efficacy, and toxicity. In the present study, we investigated the interactions between food additive silica NPs and food matrices, such as saccharides, proteins, lipids, and minerals. Quantitative analysis was performed to determine food component-NP corona using HPLC, fluorescence quenching, GC-MS, and ICP-AES. The results demonstrate that zeta potential and hydrodynamic radius of silica NPs changed in the presence of all food matrices, but their solubility was not affected. However, quantitative analysis on the interactions revealed that a small portion of food matrices interacted with silica NPs and the interactions were highly dependent on the type of food component. Moreover, minor nutrients could also affect the interactions, as evidenced by higher NP interaction with honey rather than with a simple sugar mixture containing an equivalent amount of fructose, glucose, sucrose, and maltose. These findings provide fundamental information to extend our understanding about the interactions between silica NPs and food components and to predict the interaction effect on the safety aspects of food

  18. Neptunium (IV) oxalate solubility

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1983-07-01

    The equilibrium solubility of neptunium (IV) oxalate in nitric/oxalic acid solutions was determined at 22 0 C, 45 0 C, and 60 0 C. The concentrations of nitric/oxalic acid solutions represented a wide range of free oxalate ion concentration. A mathematical solubility model was developed which is based on the formation of the known complexes of neptunium (IV) oxalate. the solubility model uses a simplified concentration parameter which is proportional to the free oxalate ion concentration. The solubility model can be used to estimate the equilibrium solubility of neptunium (IV) oxalate over a wide range of oxalic and nitric acid concentrations at each temperature

  19. The impact of solvent relative permittivity on the dimerisation of organic molecules well below their solubility limits: examples from brewed coffee and beyond.

    Science.gov (United States)

    Bradley, Ellen S; Hendon, Christopher H

    2017-03-22

    The formation of aqueous intermolecular dimers is governed by both the nature and strength of the intermolecular interactions and the entropy of dissolution. The former interaction energies are determined by the polarity of the solvent and the functionality of the solute. Using quantum chemical methods, we probe the energetics of dimer formation of representative compounds found in coffee well below their solubility limits. We find that with the exclusion of entropy, the dimer formation is thermodynamically unfavorable with negligible dependence on the dielectric medium.

  20. Hypercyclic Abelian Semigroups of Matrices on Cn

    International Nuclear Information System (INIS)

    Ayadi, Adlene; Marzougui, Habib

    2010-07-01

    We give a complete characterization of existence of dense orbit for any abelian semigroup of matrices on C n . For finitely generated semigroups, this characterization is explicit and is used to determine the minimal number of matrices in normal form over C which forms a hypercyclic abelian semigroup on C n . In particular, we show that no abelian semigroup generated by n matrices on C n can be hypercyclic. (author)

  1. Lambda-matrices and vibrating systems

    CERN Document Server

    Lancaster, Peter; Stark, M; Kahane, J P

    1966-01-01

    Lambda-Matrices and Vibrating Systems presents aspects and solutions to problems concerned with linear vibrating systems with a finite degrees of freedom and the theory of matrices. The book discusses some parts of the theory of matrices that will account for the solutions of the problems. The text starts with an outline of matrix theory, and some theorems are proved. The Jordan canonical form is also applied to understand the structure of square matrices. Classical theorems are discussed further by applying the Jordan canonical form, the Rayleigh quotient, and simple matrix pencils with late

  2. Pathological rate matrices: from primates to pathogens

    Directory of Open Access Journals (Sweden)

    Knight Rob

    2008-12-01

    Full Text Available Abstract Background Continuous-time Markov models allow flexible, parametrically succinct descriptions of sequence divergence. Non-reversible forms of these models are more biologically realistic but are challenging to develop. The instantaneous rate matrices defined for these models are typically transformed into substitution probability matrices using a matrix exponentiation algorithm that employs eigendecomposition, but this algorithm has characteristic vulnerabilities that lead to significant errors when a rate matrix possesses certain 'pathological' properties. Here we tested whether pathological rate matrices exist in nature, and consider the suitability of different algorithms to their computation. Results We used concatenated protein coding gene alignments from microbial genomes, primate genomes and independent intron alignments from primate genomes. The Taylor series expansion and eigendecomposition matrix exponentiation algorithms were compared to the less widely employed, but more robust, Padé with scaling and squaring algorithm for nucleotide, dinucleotide, codon and trinucleotide rate matrices. Pathological dinucleotide and trinucleotide matrices were evident in the microbial data set, affecting the eigendecomposition and Taylor algorithms respectively. Even using a conservative estimate of matrix error (occurrence of an invalid probability, both Taylor and eigendecomposition algorithms exhibited substantial error rates: ~100% of all exonic trinucleotide matrices were pathological to the Taylor algorithm while ~10% of codon positions 1 and 2 dinucleotide matrices and intronic trinucleotide matrices, and ~30% of codon matrices were pathological to eigendecomposition. The majority of Taylor algorithm errors derived from occurrence of multiple unobserved states. A small number of negative probabilities were detected from the Pad�� algorithm on trinucleotide matrices that were attributable to machine precision. Although the Pad

  3. EXPECTED IMPACT OF HANFORD PROCESSING ORGANICS OF PLUTONIUM DURING TANK WASTE SLUDGE RETRIEVAL

    International Nuclear Information System (INIS)

    TROYER, G.L.; WINTERS, W.I.

    2004-01-01

    This document evaluates the potential for extracting plutonium from Hanford waste tanks into residual organic solvents and how this process may have an impact on criticality specifications during the retrieval of wastes. The two controlling factors for concentrating plutonium are the solubility of the plutonium in the wastes and the extraction efficiency of the potential organic extractants that may be found in these wastes. Residual Hanford tank sludges contain plutonium in solid forms that are expected to be primarily insoluble Pu(IV) hydroxides. Evaluation of thermodynamic Pourbaix diagrams, documentation on solubility studies of various components in waste tank matrices, and actual analysis of plutonium in tank supernates all indicate that the solubility of Pu in the alkaline waste is on the order of 10 -6 M. Based on an upper limit plutonium solubility of 10 -5 M in high pH and a conservative distribution coefficient for organic extractants of a 0 for plutonium in 30% TBP at 0.07 M HNO 3 ), the estimated concentration for plutonium in the organic phase would be -7 M. This is well below the process control criteria. A significant increase in plutonium solubility or the E a o would have to occur to raise this concentration to the 0.01 M concern level for organics. Measured tank chemical component values, expected operating conditions, and the characteristics of the expected chemistry and extraction mechanisms indicate that concentration of plutonium from Hanford tank residual sludges to associated process organic extractants is significantly below levels of concern

  4. Phytosterols and their extraction from various plant matrices using supercritical carbon dioxide: a review.

    Science.gov (United States)

    Uddin, Md Salim; Sarker, Md Zaidul Islam; Ferdosh, Sahena; Akanda, Md Jahurul Haque; Easmin, Mst Sabina; Bt Shamsudin, Siti Hadijah; Bin Yunus, Kamaruzzaman

    2015-05-01

    Phytosterols provide important health benefits: in particular, the lowering of cholesterol. From environmental and commercial points of view, the most appropriate technique has been searched for extracting phytosterols from plant matrices. As a green technology, supercritical fluid extraction (SFE) using carbon dioxide (CO2) is widely used to extract bioactive compounds from different plant matrices. Several studies have been performed to extract phytosterols using supercritical CO2 (SC-CO2) and this technology has clearly offered potential advantages over conventional extraction methods. However, the efficiency of SFE technology fully relies on the processing parameters, chemistry of interest compounds, nature of the plant matrices and expertise of handling. This review covers SFE technology with particular reference to phytosterol extraction using SC-CO2. Moreover, the chemistry of phytosterols, properties of supercritical fluids (SFs) and the applied experimental designs have been discussed for better understanding of phytosterol solubility in SC-CO2. © 2014 Society of Chemical Industry.

  5. Compostos orgânicos hidrossolúveis de resíduos vegetais e seus efeitos nos atributos químicos do solo Water-soluble organic compounds in plant residue and the effects on soil chemical properties

    Directory of Open Access Journals (Sweden)

    Raquel Cátia Diehl

    2008-12-01

    Full Text Available Compostos orgânicos hidrossolúveis de resíduos vegetais depositados na superfície do solo podem melhorar a fertilidade do subsolo, pela neutralização da acidez e transporte de Ca e Mg. Com o objetivo de avaliar o efeito dos compostos orgânicos hidrossolúveis de materiais vegetais nos atributos químicos de um Latossolo Vermelho distroférrico, foi desenvolvido um experimento no Instituto Agronômico do Paraná (IAPAR, Londrina, com amostras de solo acondicionadas em colunas nas quais se aplicaram os tratamentos: água destilada, calcário incorporado na camada 0-5 cm de profundidade, calcário e percolação com extratos de nabo forrageiro, aveia preta, palha de trigo, milho e soja. No extrato percolado, foram determinados os teores de ligantes orgânicos hidrossolúveis (LOH por potenciometria com eletrodo seletivo de Cu2+; ácidos orgânicos tituláveis (AOT por titulação ácido-base e ânions orgânicos (AO pela soma de bases. As concentrações de AO e AOT variaram de 7,0 a 32,0 mmol L-1 e de LOH de 0,60 a 2,23 mmol L-1. Todos os extratos vegetais aumentaram o pH, os teores de Ca, Mg e K trocável e diminuíram a acidez potencial e o Al trocável até 15 cm de profundidade, enquanto o efeito da calagem sem extrato foi observado somente até 10 cm de profundidade. A concentração de compostos orgânicos solúveis oriundos dos materiais vegetais correlacionou-se com o pH, Al trocável, H+Al e V % do solo na camada de 0-20 cm, confirmando a participação destes na melhoria dos atributos químicos do solo e ação da calagem superficial quando o material vegetal está presente.The water-soluble organic compounds of plant residues released on the soil surface can improve the subsoil fertility, due to the neutralization of acidity and Ca and Mg transport. An experiment was conducted at the Instituto Agronomico do Parana (IAPAR, Londrina, to evaluate the effect of water-soluble organic compounds of plant extracts on the chemical

  6. Quantum Hilbert matrices and orthogonal polynomials

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Berg, Christian

    2009-01-01

    Using the notion of quantum integers associated with a complex number q≠0 , we define the quantum Hilbert matrix and various extensions. They are Hankel matrices corresponding to certain little q -Jacobi polynomials when |q|<1 , and for the special value they are closely related to Hankel matrice...

  7. The construction of factorized S-matrices

    International Nuclear Information System (INIS)

    Chudnovsky, D.V.

    1981-01-01

    We study the relationships between factorized S-matrices given as representations of the Zamolodchikov algebra and exactly solvable models constructed using the Baxter method. Several new examples of symmetric and non-symmetric factorized S-matrices are proposed. (orig.)

  8. Skew-adjacency matrices of graphs

    NARCIS (Netherlands)

    Cavers, M.; Cioaba, S.M.; Fallat, S.; Gregory, D.A.; Haemers, W.H.; Kirkland, S.J.; McDonald, J.J.; Tsatsomeros, M.

    2012-01-01

    The spectra of the skew-adjacency matrices of a graph are considered as a possible way to distinguish adjacency cospectral graphs. This leads to the following topics: graphs whose skew-adjacency matrices are all cospectral; relations between the matchings polynomial of a graph and the characteristic

  9. On Investigating GMRES Convergence using Unitary Matrices

    Czech Academy of Sciences Publication Activity Database

    Duintjer Tebbens, Jurjen; Meurant, G.; Sadok, H.; Strakoš, Z.

    2014-01-01

    Roč. 450, 1 June (2014), s. 83-107 ISSN 0024-3795 Grant - others:GA AV ČR(CZ) M100301201; GA MŠk(CZ) LL1202 Institutional support: RVO:67985807 Keywords : GMRES convergence * unitary matrices * unitary spectra * normal matrices * Krylov residual subspace * Schur parameters Subject RIV: BA - General Mathematics Impact factor: 0.939, year: 2014

  10. Solubility of metallic mercury in organic solvents; Solubilite du mercure metallique dans les solvants organiques; Rastvorimost' metallicheskoj rtuti v organicheskikh rastvoritelyakh; Solubilidad del mercurio metalico en solventes organicos

    Energy Technology Data Exchange (ETDEWEB)

    Klehr, E H; Voigt, A F [Institute for Atomic Research and Department of Chemistry, Iowa State University, Ames, IA (United States)

    1962-03-15

    The solubilities of metallic mercury at 25{sup o}C in the solvents carbon tetrachloride, 2, 2, 4-trimethylpentane, n-decane, benzene, toluene, nitrobenzene, chlorobenzene and bromobenzene have been determined by the use of Hg{sup 203} tracer. Measurements were made either by shaking mercury metal of known specific activity with the solvent, or by measuring the distribution coefficient of the metal between the solvent and water and combining this measurement with the solubility of mercury in water, or by both methods. Radioactivity was measured by counting precipitated samples with a GM counter or liquid aliquots with a well-type scintillator counter. All solubilities were in the range (4.6 to 16) x 10{sup -6} g atoms/l. For n-decane, toluene and chlorobenzene, the temperature dependence of the solubility was determined over the range 0 to 45{sup o}C. The Hildebrand-Scott theory of solubility has been applied to these systems for comparison. For the aliphatic hydrocarbons, the solubilities predicted by theory are within 35% of those observed, but for the other solvents, the predicted values are 4 to 18 times larger than those observed. Modification of the theory gives better agreement for some solvents but poorer agreement for others. Curves of log G (solubility) vs. 1/T were straight lines with slopes similar to those obtained from the Hildebrand-Scott theory but displaced from those curves. The slopes of the curves were used for the calculation of heats and entropies of solution. Entropies were also calculated from curves of log G vs. log T. The two sets of entropy values were in agreement with each other and were within one to four entropy units of the ideal entropies of mixing. (author) [French] Les auteurs ont determine la solubilite du mercure metallique a 25{sup o}C dans les solvants suivants: tetrachlorure de carbone, trimethylpentane 2, 2, 4, n-decane, benzene, toluene, nitrobenzene, chlorobenzene et bromobenzene en utilisant le mercure-203 comme

  11. Exact Inverse Matrices of Fermat and Mersenne Circulant Matrix

    Directory of Open Access Journals (Sweden)

    Yanpeng Zheng

    2015-01-01

    Full Text Available The well known circulant matrices are applied to solve networked systems. In this paper, circulant and left circulant matrices with the Fermat and Mersenne numbers are considered. The nonsingularity of these special matrices is discussed. Meanwhile, the exact determinants and inverse matrices of these special matrices are presented.

  12. SAR matrices: automated extraction of information-rich SAR tables from large compound data sets.

    Science.gov (United States)

    Wassermann, Anne Mai; Haebel, Peter; Weskamp, Nils; Bajorath, Jürgen

    2012-07-23

    We introduce the SAR matrix data structure that is designed to elucidate SAR patterns produced by groups of structurally related active compounds, which are extracted from large data sets. SAR matrices are systematically generated and sorted on the basis of SAR information content. Matrix generation is computationally efficient and enables processing of large compound sets. The matrix format is reminiscent of SAR tables, and SAR patterns revealed by different categories of matrices are easily interpretable. The structural organization underlying matrix formation is more flexible than standard R-group decomposition schemes. Hence, the resulting matrices capture SAR information in a comprehensive manner.

  13. The effect of tree species on seasonal fluctuations in water-soluble and hot water-extractable organic matter at post-mining sites

    Czech Academy of Sciences Publication Activity Database

    Cepáková, Šárka; Tošner, Z.; Frouz, Jan

    2016-01-01

    Roč. 275, August (2016), s. 19-27 ISSN 0016-7061 Grant - others:GA ČR(CZ) GAP504/12/1288; GAJU(CZ) GAJU/04-146/2013/P Program:GA Institutional support: RVO:60077344 Keywords : HWC * liquid-state 1H NMR * seasonality * soil organic carbon * water-extractable organic matter Subject RIV: DF - Soil Science Impact factor: 4.036, year: 2016

  14. Environmental assessment of waste matrices contaminated with arsenic.

    Science.gov (United States)

    Sanchez, F; Garrabrants, A C; Vandecasteele, C; Moszkowicz, P; Kosson, D S

    2003-01-31

    The use of equilibrium-based and mass transfer-based leaching tests has been proposed to provide an integrated assessment of leaching processes from solid wastes. The objectives of the research presented here are to (i) validate this assessment approach for contaminated soils and cement-based matrices, (ii) evaluate the use of diffusion and coupled dissolution-diffusion models for estimating constituent release, and (iii) evaluate model parameterization using results from batch equilibrium leaching tests and physical characterization. The test matrices consisted of (i) a soil contaminated with arsenic from a pesticide production facility, (ii) the same soil subsequently treated by a Portland cement stabilization/solidification (S/S) process, and (iii) a synthetic cement-based matrix spiked with arsenic(III) oxide. Results indicated that a good assessment of contaminant release from contaminated soils and cement-based S/S treated wastes can be obtained by the integrated use of equilibrium-based and mass transfer-based leaching tests in conjunction with the appropriate release model. During the time scale of laboratory testing, the release of arsenic from the contaminated soil matrix was governed by diffusion and the solubility of arsenic in the pore solution while the release of arsenic from the cement-based matrices was mainly controlled by solubilization at the interface between the matrix and the bulk leaching solution. In addition, results indicated that (i) estimation of the activity coefficient within the matrix pore water is necessary for accurate prediction of constituent release rates and (ii) inaccurate representation of the factors controlling release during laboratory testing can result in significant errors in release estimates.

  15. Application of different methodologies in the preparation of organic matrices for determination of trace elements by differential pulse anodic stripping voltammetry; Aplicacao de diferentes metodologias na preparacao de matrizes organicas para a determinacao voltametrica de elementos traco

    Energy Technology Data Exchange (ETDEWEB)

    Sisti, Cristina

    2001-07-01

    The determination of trace elements in food samples is of great importance for the human health, considering the factors of essentiality and toxicity. On the other hand, the chemical analysis is largely affected for the steps of sample preparation; laboratory contamination of the sample and the reagents or still volatilization and losses of the elements. If these parameters are not controlled the achieved precision and accuracy could be low. In this work, the content of zinc, cadmium, lead and copper was determined in adults diet samples collected by duplicate portion technique and bovine liver, applying the differential pulse anodic stripping voltametry - (DP-ASV) technique. In the digestion of the matrices in acid medium, conventional methodologies were used, conductive heating in open recipients and equipment with microwaves source in open and closed vessels. The best procedure was the sample digestion by microwaves, in closed vessels and the other treatments made in controlled atmosphere with hood laminar-airflow class 100. The established methodology was validated with the use of a certified sample as reference (NIST - bovine liver 1577b). (author)

  16. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis; Formulation d'un gel oxydant a matrice organique applicable a la decontamination nucleaire: proprietes rheologiques, acido-basiques et ozonolyse de la matrice

    Energy Technology Data Exchange (ETDEWEB)

    Rouy, E

    2003-10-15

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and {sup 1}H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  17. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis; Formulation d'un gel oxydant a matrice organique applicable a la decontamination nucleaire: proprietes rheologiques, acido-basiques et ozonolyse de la matrice

    Energy Technology Data Exchange (ETDEWEB)

    Rouy, E

    2003-10-15

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and {sup 1}H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  18. The Antitriangular Factorization of Saddle Point Matrices

    KAUST Repository

    Pestana, J.

    2014-01-01

    Mastronardi and Van Dooren [SIAM J. Matrix Anal. Appl., 34 (2013), pp. 173-196] recently introduced the block antitriangular ("Batman") decomposition for symmetric indefinite matrices. Here we show the simplification of this factorization for saddle point matrices and demonstrate how it represents the common nullspace method. We show that rank-1 updates to the saddle point matrix can be easily incorporated into the factorization and give bounds on the eigenvalues of matrices important in saddle point theory. We show the relation of this factorization to constraint preconditioning and how it transforms but preserves the structure of block diagonal and block triangular preconditioners. © 2014 Society for Industrial and Applied Mathematics.

  19. Polynomial sequences generated by infinite Hessenberg matrices

    Directory of Open Access Journals (Sweden)

    Verde-Star Luis

    2017-01-01

    Full Text Available We show that an infinite lower Hessenberg matrix generates polynomial sequences that correspond to the rows of infinite lower triangular invertible matrices. Orthogonal polynomial sequences are obtained when the Hessenberg matrix is tridiagonal. We study properties of the polynomial sequences and their corresponding matrices which are related to recurrence relations, companion matrices, matrix similarity, construction algorithms, and generating functions. When the Hessenberg matrix is also Toeplitz the polynomial sequences turn out to be of interpolatory type and we obtain additional results. For example, we show that every nonderogative finite square matrix is similar to a unique Toeplitz-Hessenberg matrix.

  20. Solubility of actinides and surrogates in nuclear glasses

    International Nuclear Information System (INIS)

    Lopez, Ch.

    2003-01-01

    The nuclear wastes are currently incorporated in borosilicate glass matrices. The resulting glass must be perfectly homogeneous. The work discussed here is a study of actinide (thorium and plutonium) solubility in borosilicate glass, undertaken to assess the extent of actinide solubility in the glass and to understand the mechanisms controlling actinide solubilization. Glass specimens containing; actinide surrogates were used to prepare and optimize the fabrication of radioactive glass samples. These preliminary studies revealed that actinide Surrogates solubility in the glass was enhanced by controlling the processing temperature, the dissolution kinetic of the surrogate precursors, the glass composition and the oxidizing versus reducing conditions. The actinide solubility was investigated in the borosilicate glass. The evolution of thorium solubility in borosilicate glass was determined for temperatures ranging from 1200 deg C to 1400 deg C.Borosilicate glass specimens containing plutonium were fabricated. The experimental result showed that the plutonium solubility limit ranged from 1 to 2.5 wt% PuO 2 at 1200 deg C. A structural approach based on the determination of the local structure around actinides and their surrogates by EXAFS spectroscopy was used to determine their structural role in the glass and the nature of their bonding with the vitreous network. This approach revealed a correlation between the length of these bonds and the solubility of the actinides and their surrogates. (author)

  1. Synchronous correlation matrices and Connes’ embedding conjecture

    Energy Technology Data Exchange (ETDEWEB)

    Dykema, Kenneth J., E-mail: kdykema@math.tamu.edu [Department of Mathematics, Texas A& M University, College Station, Texas 77843-3368 (United States); Paulsen, Vern, E-mail: vern@math.uh.edu [Department of Mathematics, University of Houston, Houston, Texas 77204 (United States)

    2016-01-15

    In the work of Paulsen et al. [J. Funct. Anal. (in press); preprint arXiv:1407.6918], the concept of synchronous quantum correlation matrices was introduced and these were shown to correspond to traces on certain C*-algebras. In particular, synchronous correlation matrices arose in their study of various versions of quantum chromatic numbers of graphs and other quantum versions of graph theoretic parameters. In this paper, we develop these ideas further, focusing on the relations between synchronous correlation matrices and microstates. We prove that Connes’ embedding conjecture is equivalent to the equality of two families of synchronous quantum correlation matrices. We prove that if Connes’ embedding conjecture has a positive answer, then the tracial rank and projective rank are equal for every graph. We then apply these results to more general non-local games.

  2. Discrete canonical transforms that are Hadamard matrices

    International Nuclear Information System (INIS)

    Healy, John J; Wolf, Kurt Bernardo

    2011-01-01

    The group Sp(2,R) of symplectic linear canonical transformations has an integral kernel which has quadratic and linear phases, and which is realized by the geometric paraxial optical model. The discrete counterpart of this model is a finite Hamiltonian system that acts on N-point signals through N x N matrices whose elements also have a constant absolute value, although they do not form a representation of that group. Those matrices that are also unitary are Hadamard matrices. We investigate the manifolds of these N x N matrices under the Sp(2,R) equivalence imposed by the model, and find them to be on two-sided cosets. By means of an algorithm we determine representatives that lead to collections of mutually unbiased bases.

  3. ESTIMATION OF FUNCTIONALS OF SPARSE COVARIANCE MATRICES.

    Science.gov (United States)

    Fan, Jianqing; Rigollet, Philippe; Wang, Weichen

    High-dimensional statistical tests often ignore correlations to gain simplicity and stability leading to null distributions that depend on functionals of correlation matrices such as their Frobenius norm and other ℓ r norms. Motivated by the computation of critical values of such tests, we investigate the difficulty of estimation the functionals of sparse correlation matrices. Specifically, we show that simple plug-in procedures based on thresholded estimators of correlation matrices are sparsity-adaptive and minimax optimal over a large class of correlation matrices. Akin to previous results on functional estimation, the minimax rates exhibit an elbow phenomenon. Our results are further illustrated in simulated data as well as an empirical study of data arising in financial econometrics.

  4. The Antitriangular Factorization of Saddle Point Matrices

    KAUST Repository

    Pestana, J.; Wathen, A. J.

    2014-01-01

    Mastronardi and Van Dooren [SIAM J. Matrix Anal. Appl., 34 (2013), pp. 173-196] recently introduced the block antitriangular ("Batman") decomposition for symmetric indefinite matrices. Here we show the simplification of this factorization for saddle

  5. Flux Jacobian Matrices For Equilibrium Real Gases

    Science.gov (United States)

    Vinokur, Marcel

    1990-01-01

    Improved formulation includes generalized Roe average and extension to three dimensions. Flux Jacobian matrices derived for use in numerical solutions of conservation-law differential equations of inviscid flows of ideal gases extended to real gases. Real-gas formulation of these matrices retains simplifying assumptions of thermodynamic and chemical equilibrium, but adds effects of vibrational excitation, dissociation, and ionization of gas molecules via general equation of state.

  6. Porcine skin as a source of biodegradable matrices: alkaline treatment and glutaraldehyde crosslinking

    Directory of Open Access Journals (Sweden)

    Fabiana T. Rodrigues

    2010-06-01

    Full Text Available In this work, the modifications promoted by alkaline hydrolysis and glutaraldehyde (GA crosslinking on type I collagen found in porcine skin have been studied. Collagen matrices were obtained from the alkaline hydrolysis of porcine skin, with subsequent GA crosslinking in different concentrations and reaction times. The elastin content determination showed that independent of the treatment, elastin was present in the matrices. Results obtained from in vitro trypsin degradation indicated that with the increase of GA concentration and reaction time, the degradation rate decreased. From thermogravimetry and differential scanning calorimetry analysis it can be observed that the collagen in the matrices becomes more resistant to thermal degradation as a consequence of the increasing crosslink degree. Scanning electron microscopy analysis indicated that after the GA crosslinking, collagen fibers become more organized and well-defined. Therefore, the preparations of porcine skin matrices with different degradation rates, which can be used in soft tissue reconstruction, are viable.

  7. Electrospun composite matrices of poly(ε-caprolactone)-montmorillonite made using tenside free Pickering emulsions

    International Nuclear Information System (INIS)

    Samanta, Archana; Takkar, Sonam; Kulshreshtha, Ritu; Nandan, Bhanu; Srivastava, Rajiv K.

    2016-01-01

    The production of composite electrospun matrices of poly(ε-caprolactone) (PCL) using an emulsifier-free emulsion, made with minimal organic solvent, as precursor is reported. Pickering emulsions of PCL were prepared using modified montmorillonite (MMT) clay as the stabilizer. Hydrophobic tallow group of the modified MMT clay resulted in analogous interaction of clay with oil and aqueous phase and its adsorption at the interface to provide stability to the resultant emulsion. Composite fibrous matrices of PCL and MMT were produced using electrospinning under controlled conditions. The fiber fineness was found to alter with PCL concentration and volume fraction of the aqueous and oil phases. A higher tensile strength and modulus was obtained with inclusion of MMT in PCL electrospun matrix in comparison to a matrix made using neat PCL. The presence of clay in the fibrous matrix did not change the cell proliferation efficiency in comparison to neat PCL matrix. Composite fibrous matrices of PCL/MMT bearing enhanced tensile properties may find applications in areas other than tissue engineering for example food packaging and filtration. - Highlights: • Tenside free, clay stabilized Pickering emulsion of PCL is made with minimal organic solvent. • Organic–inorganic composite fibrous matrices were produced via emulsion electrospinning. • Fiber fineness was efficiently controlled by variation in emulsion formulation. • Fibrous matrices of high tensile strength and modulus were obtained in comparison to neat PCL matrix. • PCL/clay matrices showed effective cell proliferation as a neat PCL matrix.

  8. Electrospun composite matrices of poly(ε-caprolactone)-montmorillonite made using tenside free Pickering emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Samanta, Archana [Department of Textile Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Takkar, Sonam; Kulshreshtha, Ritu [Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Nandan, Bhanu [Department of Textile Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Srivastava, Rajiv K., E-mail: rajiv@textile.iitd.ac.in [Department of Textile Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)

    2016-12-01

    The production of composite electrospun matrices of poly(ε-caprolactone) (PCL) using an emulsifier-free emulsion, made with minimal organic solvent, as precursor is reported. Pickering emulsions of PCL were prepared using modified montmorillonite (MMT) clay as the stabilizer. Hydrophobic tallow group of the modified MMT clay resulted in analogous interaction of clay with oil and aqueous phase and its adsorption at the interface to provide stability to the resultant emulsion. Composite fibrous matrices of PCL and MMT were produced using electrospinning under controlled conditions. The fiber fineness was found to alter with PCL concentration and volume fraction of the aqueous and oil phases. A higher tensile strength and modulus was obtained with inclusion of MMT in PCL electrospun matrix in comparison to a matrix made using neat PCL. The presence of clay in the fibrous matrix did not change the cell proliferation efficiency in comparison to neat PCL matrix. Composite fibrous matrices of PCL/MMT bearing enhanced tensile properties may find applications in areas other than tissue engineering for example food packaging and filtration. - Highlights: • Tenside free, clay stabilized Pickering emulsion of PCL is made with minimal organic solvent. • Organic–inorganic composite fibrous matrices were produced via emulsion electrospinning. • Fiber fineness was efficiently controlled by variation in emulsion formulation. • Fibrous matrices of high tensile strength and modulus were obtained in comparison to neat PCL matrix. • PCL/clay matrices showed effective cell proliferation as a neat PCL matrix.

  9. Highly soluble [1]benzothieno[3,2-b]benzothiophene (BTBT) derivatives for high-performance, solution-processed organic field-effect transistors.

    Science.gov (United States)

    Ebata, Hideaki; Izawa, Takafumi; Miyazaki, Eigo; Takimiya, Kazuo; Ikeda, Masaaki; Kuwabara, Hirokazu; Yui, Tatsuto

    2007-12-26

    2,7-Dialkyl[1]benzothieno[3,2-b]benzothiophenes were tested as solution-processible molecular semiconductors. Thin films of the organic semiconductors deposited on Si/SiO2 substrates by spin coating have well-ordered structures as confirmed by XRD analysis. Evaluations of the devices under ambient conditions showed typical p-channel FET responses with the field-effect mobility higher than 1.0 cm2 V-1 s-1 and Ion/Ioff of approximately 10(7).

  10. Influence of calcium and phosphorus, lactose, and salt-to-moisture ratio on Cheddar cheese quality: changes in residual sugars and water-soluble organic acids during ripening.

    Science.gov (United States)

    Upreti, P; McKay, L L; Metzger, L E

    2006-02-01

    Cheddar cheese ripening involves the conversion of lactose to glucose and galactose or galactose-6-phosphate by starter and nonstarter lactic acid bacteria. Under ideal conditions (i.e., where bacteria grow under no stress of pH, water activity, and salt), these sugars are mainly converted to lactic acid. However, during ripening of cheese, survival and growth of bacteria occurs under the stressed condition of low pH, low water activity, and high salt content. This forces bacteria to use alternate biochemical pathways resulting in production of other organic acids. The objective of this study was to determine if the level and type of organic acids produced during ripening was influenced by calcium (Ca) and phosphorus (P), residual lactose, and salt-to-moisture ratio (S/M) of cheese. Eight cheeses with 2 levels of Ca and P (0.67 and 0.47% vs. 0.53 and 0.39%, respectively), lactose at pressing (2.4 vs. 0.78%), and S/M (6.4 vs. 4.8%) were manufactured. The cheeses were analyzed for organic acids (citric, orotic, pyruvic, lactic, formic, uric, acetic, propanoic, and butyric acids) and residual sugars (lactose, galactose) during 48 wk of ripening using an HPLC-based method. Different factors influenced changes in concentration of residual sugars and organic acids during ripening and are discussed in detail. Our results indicated that the largest decrease in lactose and the largest increase in lactic acid occurred between salting and d 1 of ripening. It was interesting to observe that although the lactose content in cheese was influenced by several factors (Ca and P, residual lactose, and S/M), the concentration of lactic acid was influenced only by S/M. More lactic acid was produced in low S/M treatments compared with high S/M treatments. Although surprising for Cheddar cheese, a substantial amount (0.2 to 0.4%) of galactose was observed throughout ripening in all treatments. Minor changes in the levels of citric, uric, butyric, and propanoic acids were observed during

  11. Study of remobilization polycyclic aromatic hydrocarbons (PAHs) in contaminated matrices

    International Nuclear Information System (INIS)

    Belkessam, L.; Vessigaud, S.; Laboudigue, A.; Vessigaud, S.; Perrin-Ganier, C.; Schiavon, M.; Denys, S.

    2005-01-01

    Polycyclic aromatic hydrocarbons (PAHs) originate from many pyrolysis processes. They are widespread environmental pollutants because some of them present toxic and genotoxic properties. In coal pyrolysis sites such as former manufactured gas plants and coke production plants, coal tar is a major source of PAHs. The management of such sites requires better understanding of the mechanisms that control release of PAHs to the biosphere. Determining total PAH concentrations is not sufficient since it does not inform about the pollutants availability to environmental processes. The fate and transport of PAHs in soil are governed by sorption and microbial processes which are well documented. Globally, enhancing retention of the compounds by a solid matrix reduces the risk of pollutant dispersion, but decreases their accessibility to microbial microflora. Conversely, the remobilization of organics from contaminated solid matrices represents a potential hazard since these pollutants can reach groundwater resources. However the available data are often obtained from laboratory experiments in which many field parameters can not be taken into account (long term, temperature, co-pollution, ageing phenomenon, heterogenous distribution of pollution). The present work focuses on the influence assessment and understanding of some of these parameters on PAHs remobilization from heavily polluted matrices in near-field conditions (industrial contaminated matrices, high contact time, ..). Results concerning effects of temperature and physical state of pollution (dispersed among the soil or condensed in small clusters or in coal tar) are presented. (authors)

  12. Protein matrices for wound dressings =

    Science.gov (United States)

    Vasconcelos, Andreia Joana Costa

    Fibrous proteins such as silk fibroin (SF), keratin (K) and elastin (EL) are able to mimic the extracellular matrix (ECM) that allows their recognition under physiological conditions. The impressive mechanical properties, the environmental stability, in combination with their biocompatibility and control of morphology, provide an important basis to use these proteins in biomedical applications like protein-based wound dressings. Along time the concept of wound dressings has changed from the traditional dressings such as honey or natural fibres, used just to protect the wound from external factors, to the interactive dressings of the present. Wounds can be classified in acute that heal in the expected time frame, and chronic, which fail to heal because the orderly sequence of events is disrupted at one or more stages of the healing process. Moreover, chronic wound exudates contain high levels of tissue destructive proteolytic enzymes such as human neutrophil elastase (HNE) that need to be controlled for a proper healing. The aim of this work is to exploit the self-assemble properties of silk fibroin, keratin and elastin for the development of new protein materials to be used as wound dressings: i) evaluation of the blending effect on the physical and chemical properties of the materials; ii) development of materials with different morphologies; iii) assessment of the cytocompatibility of the protein matrices; iv) ultimately, study the ability of the developed protein matrices as wound dressings through the use of human chronic wound exudate; v) use of innovative short peptide sequences that allow to target the control of high levels of HNE found on chronic wounds. Chapter III reports the preparation of silk fibroin/keratin (SF/K) blend films by solvent casting evaporation. Two solvent systems, aqueous and acidic, were used for the preparation of films from fibroin and keratin extracted from the respective silk and wool fibres. The effect of solvent system used was

  13. Sports drug testing using complementary matrices: Advantages and limitations.

    Science.gov (United States)

    Thevis, Mario; Geyer, Hans; Tretzel, Laura; Schänzer, Wilhelm

    2016-10-25

    Today, routine doping controls largely rely on testing whole blood, serum, and urine samples. These matrices allow comprehensively covering inorganic as well as low and high molecular mass organic analytes relevant to doping controls and are collecting and transferring from sampling sites to accredited anti-doping laboratories under standardized conditions. Various aspects including time and cost-effectiveness as well as intrusiveness and invasiveness of the sampling procedure but also analyte stability and breadth of the contained information have been motivation to consider and assess values potentially provided and added to modern sports drug testing programs by alternative matrices. Such alternatives could be dried blood spots (DBS), dried plasma spots (DPS), oral fluid (OF), exhaled breath (EB), and hair. In this review, recent developments and test methods concerning these alternative matrices and expected or proven contributions as well as limitations of these specimens in the context of the international anti-doping fight are presented and discussed, guided by current regulations for prohibited substances and methods of doping as established by the World Anti-Doping Agency (WADA). Focusing on literature published between 2011 and 2015, examples for doping control analytical assays concerning non-approved substances, anabolic agents, peptide hormones/growth factors/related substances and mimetics, β 2 -agonists, hormone and metabolic modulators, diuretics and masking agents, stimulants, narcotics, cannabinoids, glucocorticoids, and beta-blockers were selected to outline the advantages and limitations of the aforementioned alternative matrices as compared to conventional doping control samples (i.e. urine and blood/serum). Copyright © 2016 Elsevier B.V. All rights reserved.

  14. MERSENNE AND HADAMARD MATRICES CALCULATION BY SCARPIS METHOD

    Directory of Open Access Journals (Sweden)

    N. A. Balonin

    2014-05-01

    Full Text Available Purpose. The paper deals with the problem of basic generalizations of Hadamard matrices associated with maximum determinant matrices or not optimal by determinant matrices with orthogonal columns (weighing matrices, Mersenne and Euler matrices, ets.; calculation methods for the quasi-orthogonal local maximum determinant Mersenne matrices are not studied enough sufficiently. The goal of this paper is to develop the theory of Mersenne and Hadamard matrices on the base of generalized Scarpis method research. Methods. Extreme solutions are found in general by minimization of maximum for absolute values of the elements of studied matrices followed by their subsequent classification according to the quantity of levels and their values depending on orders. Less universal but more effective methods are based on structural invariants of quasi-orthogonal matrices (Silvester, Paley, Scarpis methods, ets.. Results. Generalizations of Hadamard and Belevitch matrices as a family of quasi-orthogonal matrices of odd orders are observed; they include, in particular, two-level Mersenne matrices. Definitions of section and layer on the set of generalized matrices are proposed. Calculation algorithms for matrices of adjacent layers and sections by matrices of lower orders are described. Approximation examples of the Belevitch matrix structures up to 22-nd critical order by Mersenne matrix of the third order are given. New formulation of the modified Scarpis method to approximate Hadamard matrices of high orders by lower order Mersenne matrices is proposed. Williamson method is described by example of one modular level matrices approximation by matrices with a small number of levels. Practical relevance. The efficiency of developing direction for the band-pass filters creation is justified. Algorithms for Mersenne matrices design by Scarpis method are used in developing software of the research program complex. Mersenne filters are based on the suboptimal by

  15. A Brief Historical Introduction to Matrices and Their Applications

    Science.gov (United States)

    Debnath, L.

    2014-01-01

    This paper deals with the ancient origin of matrices, and the system of linear equations. Included are algebraic properties of matrices, determinants, linear transformations, and Cramer's Rule for solving the system of algebraic equations. Special attention is given to some special matrices, including matrices in graph theory and electrical…

  16. Single crystalline growth of a soluble organic semiconductor in a parallel aligned liquid crystal solvent using rubbing-treated polyimide films

    Science.gov (United States)

    Matsuzaki, Tomoya; Shibata, Yosei; Takeda, Risa; Ishinabe, Takahiro; Fujikake, Hideo

    2017-01-01

    For directional control of organic single crystals, we propose a crystal growth method using liquid crystal as the solvent. In this study, we examined the formation of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) single crystals using a parallel aligned liquid crystal (LC) cell and rubbing-treated polyimide films in order to clarify the effects of LC alignment on anisotropic C8-BTBT crystal growth. Based on the results, we found that the crystal growth direction of C8-BTBT single crystals was related to the direction of the aligned LC molecules because of rubbing treatment. Moreover, by optical evaluation, we found that the C8-BTBT single crystals have a aligned molecular structure.

  17. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles.

    Science.gov (United States)

    Unice, Kenneth M; Bare, Jennifer L; Kreider, Marisa L; Panko, Julie M

    2015-11-15

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N'-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f(C)), tire wear (f(W)), terrestrial weathering (f(S)), leaching from TRWP (f(L)), and environmental availability from TRWP (f(A)) by liquid chromatography-tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F(T)) and release to water (FR) were calculated for the tire chemicals and 13 transformation products. F(T) for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5×10(-4) (6-PPD) to 0.06 (CBS) was observed for F(R) at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p<0.05) in the weathering factor, f(S), were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f(L), and environmental availability factor, f(A), was also observed when chemicals were categorized by log K(ow). Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Soluble Antioxidant Compounds Regenerate the Antioxidants Bound to Insoluble Parts of Foods

    NARCIS (Netherlands)

    Celik, E.E.; Gökmen, V.; Fogliano, V.

    2013-01-01

    This study aimed to investigate the regeneration potential of antioxidant capacity of an insoluble food matrix. Investigations were performed in vitro with several food matrices rich in dietary fiber (DF) and bound antioxidants. After removal of the soluble fraction, the antioxidant capacity (AC) of

  19. Bayesian Nonparametric Clustering for Positive Definite Matrices.

    Science.gov (United States)

    Cherian, Anoop; Morellas, Vassilios; Papanikolopoulos, Nikolaos

    2016-05-01

    Symmetric Positive Definite (SPD) matrices emerge as data descriptors in several applications of computer vision such as object tracking, texture recognition, and diffusion tensor imaging. Clustering these data matrices forms an integral part of these applications, for which soft-clustering algorithms (K-Means, expectation maximization, etc.) are generally used. As is well-known, these algorithms need the number of clusters to be specified, which is difficult when the dataset scales. To address this issue, we resort to the classical nonparametric Bayesian framework by modeling the data as a mixture model using the Dirichlet process (DP) prior. Since these matrices do not conform to the Euclidean geometry, rather belongs to a curved Riemannian manifold,existing DP models cannot be directly applied. Thus, in this paper, we propose a novel DP mixture model framework for SPD matrices. Using the log-determinant divergence as the underlying dissimilarity measure to compare these matrices, and further using the connection between this measure and the Wishart distribution, we derive a novel DPM model based on the Wishart-Inverse-Wishart conjugate pair. We apply this model to several applications in computer vision. Our experiments demonstrate that our model is scalable to the dataset size and at the same time achieves superior accuracy compared to several state-of-the-art parametric and nonparametric clustering algorithms.

  20. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles

    International Nuclear Information System (INIS)

    Unice, Kenneth M.; Bare, Jennifer L.; Kreider, Marisa L.; Panko, Julie M.

    2015-01-01

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f C ), tire wear (f W ), terrestrial weathering (f S ), leaching from TRWP (f L ), and environmental availability from TRWP (f A ) by liquid chromatography–tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F T ) and release to water (F R ) were calculated for the tire chemicals and 13 transformation products. F T for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5 × 10 −4 (6-PPD) to 0.06 (CBS) was observed for F R at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p < 0.05) in the weathering factor, f S , were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f L , and environmental availability factor, f A, was also observed when chemicals were categorized by log K ow . Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. - Highlights: • Studied two vulcanization accelerators and an antioxidant additive used in tire tread

  1. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles

    Energy Technology Data Exchange (ETDEWEB)

    Unice, Kenneth M., E-mail: ken.unice@cardno.com; Bare, Jennifer L.; Kreider, Marisa L.; Panko, Julie M.

    2015-11-15

    Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f{sub C}), tire wear (f{sub W}), terrestrial weathering (f{sub S}), leaching from TRWP (f{sub L}), and environmental availability from TRWP (f{sub A}) by liquid chromatography–tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F{sub T}) and release to water (F{sub R}) were calculated for the tire chemicals and 13 transformation products. F{sub T} for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5 × 10{sup −4} (6-PPD) to 0.06 (CBS) was observed for F{sub R} at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p < 0.05) in the weathering factor, f{sub S}, were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f{sub L}, and environmental availability factor, f{sub A,} was also observed when chemicals were categorized by log K{sub ow}. Our methodology should be useful for lifecycle analysis of other functional polymer chemicals. - Highlights: • Studied two vulcanization

  2. Uncertainty assessment of source attribution of PM(2.5) and its water-soluble organic carbon content using different biomass burning tracers in positive matrix factorization analysis--a case study in Beijing, China.

    Science.gov (United States)

    Tao, Jun; Zhang, Leiming; Zhang, Renjian; Wu, Yunfei; Zhang, Zhisheng; Zhang, Xiaoling; Tang, Yixi; Cao, Junji; Zhang, Yuanhang

    2016-02-01

    Daily PM2.5 samples were collected at an urban site in Beijing during four one-month periods in 2009-2010, with each period in a different season. Samples were subject to chemical analysis for various chemical components including major water-soluble ions, organic carbon (OC) and water-soluble organic carbon (WSOC), element carbon (EC), trace elements, anhydrosugar levoglucosan (LG), and mannosan (MN). Three sets of source profiles of PM2.5 were first identified through positive matrix factorization (PMF) analysis using single or combined biomass tracers - non-sea salt potassium (nss-K(+)), LG, and a combination of nss-K(+) and LG. The six major source factors of PM2.5 included secondary inorganic aerosol, industrial pollution, soil dust, biomass burning, traffic emission, and coal burning, which were estimated to contribute 31±37%, 39±28%, 14±14%, 7±7%, 5±6%, and 4±8%, respectively, to PM2.5 mass if using the nss-K(+) source profiles, 22±19%, 29±17%, 20±20%, 13±13%, 12±10%, and 4±6%, respectively, if using the LG source profiles, and 21±17%, 31±18%, 19±19%, 11±12%, 14±11%, and 4±6%, respectively, if using the combined nss-K(+) and LG source profiles. The uncertainties in the estimation of biomass burning contributions to WSOC due to the different choices of biomass burning tracers were around 3% annually and up to 24% seasonally in terms of absolute percentage contributions, or on a factor of 1.7 annually and up to a factor of 3.3 seasonally in terms of the actual concentrations. The uncertainty from the major source (e.g. industrial pollution) was on a factor of 1.9 annually and up to a factor of 2.5 seasonally in the estimated WSOC concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Random matrices and random difference equations

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1975-01-01

    Mathematical models leading to products of random matrices and random difference equations are discussed. A one-compartment model with random behavior is introduced, and it is shown how the average concentration in the discrete time model converges to the exponential function. This is of relevance to understanding how radioactivity gets trapped in bone structure in blood--bone systems. The ideas are then generalized to two-compartment models and mammillary systems, where products of random matrices appear in a natural way. The appearance of products of random matrices in applications in demography and control theory is considered. Then random sequences motivated from the following problems are studied: constant pulsing and random decay models, random pulsing and constant decay models, and random pulsing and random decay models

  4. Quantum Entanglement and Reduced Density Matrices

    Science.gov (United States)

    Purwanto, Agus; Sukamto, Heru; Yuwana, Lila

    2018-05-01

    We investigate entanglement and separability criteria of multipartite (n-partite) state by examining ranks of its reduced density matrices. Firstly, we construct the general formula to determine the criterion. A rank of origin density matrix always equals one, meanwhile ranks of reduced matrices have various ranks. Next, separability and entanglement criterion of multipartite is determined by calculating ranks of reduced density matrices. In this article we diversify multipartite state criteria into completely entangled state, completely separable state, and compound state, i.e. sub-entangled state and sub-entangledseparable state. Furthermore, we also shorten the calculation proposed by the previous research to determine separability of multipartite state and expand the methods to be able to differ multipartite state based on criteria above.

  5. Forecasting Covariance Matrices: A Mixed Frequency Approach

    DEFF Research Database (Denmark)

    Halbleib, Roxana; Voev, Valeri

    This paper proposes a new method for forecasting covariance matrices of financial returns. The model mixes volatility forecasts from a dynamic model of daily realized volatilities estimated with high-frequency data with correlation forecasts based on daily data. This new approach allows for flexi......This paper proposes a new method for forecasting covariance matrices of financial returns. The model mixes volatility forecasts from a dynamic model of daily realized volatilities estimated with high-frequency data with correlation forecasts based on daily data. This new approach allows...... for flexible dependence patterns for volatilities and correlations, and can be applied to covariance matrices of large dimensions. The separate modeling of volatility and correlation forecasts considerably reduces the estimation and measurement error implied by the joint estimation and modeling of covariance...

  6. Advanced incomplete factorization algorithms for Stiltijes matrices

    Energy Technology Data Exchange (ETDEWEB)

    Il`in, V.P. [Siberian Division RAS, Novosibirsk (Russian Federation)

    1996-12-31

    The modern numerical methods for solving the linear algebraic systems Au = f with high order sparse matrices A, which arise in grid approximations of multidimensional boundary value problems, are based mainly on accelerated iterative processes with easily invertible preconditioning matrices presented in the form of approximate (incomplete) factorization of the original matrix A. We consider some recent algorithmic approaches, theoretical foundations, experimental data and open questions for incomplete factorization of Stiltijes matrices which are {open_quotes}the best{close_quotes} ones in the sense that they have the most advanced results. Special attention is given to solving the elliptic differential equations with strongly variable coefficients, singular perturbated diffusion-convection and parabolic equations.

  7. Wishart and anti-Wishart random matrices

    International Nuclear Information System (INIS)

    Janik, Romuald A; Nowak, Maciej A

    2003-01-01

    We provide a compact exact representation for the distribution of the matrix elements of the Wishart-type random matrices A † A, for any finite number of rows and columns of A, without any large N approximations. In particular, we treat the case when the Wishart-type random matrix contains redundant, non-random information, which is a new result. This representation is of interest for a procedure for reconstructing the redundant information hidden in Wishart matrices, with potential applications to numerous models based on biological, social and artificial intelligence networks

  8. Topological expansion of the chain of matrices

    International Nuclear Information System (INIS)

    Eynard, B.; Ferrer, A. Prats

    2009-01-01

    We solve the loop equations to all orders in 1/N 2 , for the Chain of Matrices matrix model (with possibly an external field coupled to the last matrix of the chain). We show that the topological expansion of the free energy, is, like for the 1 and 2-matrix model, given by the symplectic invariants of [19]. As a consequence, we find the double scaling limit explicitly, and we discuss modular properties, large N asymptotics. We also briefly discuss the limit of an infinite chain of matrices (matrix quantum mechanics).

  9. Partitioning sparse rectangular matrices for parallel processing

    Energy Technology Data Exchange (ETDEWEB)

    Kolda, T.G.

    1998-05-01

    The authors are interested in partitioning sparse rectangular matrices for parallel processing. The partitioning problem has been well-studied in the square symmetric case, but the rectangular problem has received very little attention. They will formalize the rectangular matrix partitioning problem and discuss several methods for solving it. They will extend the spectral partitioning method for symmetric matrices to the rectangular case and compare this method to three new methods -- the alternating partitioning method and two hybrid methods. The hybrid methods will be shown to be best.

  10. Soluble CD163

    DEFF Research Database (Denmark)

    Møller, Holger J

    2012-01-01

    CD163 is an endocytic receptor for haptoglobin-hemoglobin complexes and is expressed solely on macrophages and monocytes. As a result of ectodomain shedding, the extracellular portion of CD163 circulates in blood as a soluble protein (sCD163) at 0.7-3.9 mg/l in healthy individuals. The function o...

  11. Solubility Part 1

    NARCIS (Netherlands)

    Tantra, Ratna; Bolea, Eduardo; Bouwmeester, H.; Rey-Castro, Carlos; David, C.A.A.; Dogné, Jean Michel; Laborda, Francisco; Laloy, Julie; Robinson, Kenneth N.; Undas, A.K.; Zande, van der M.

    2016-01-01

    This chapter gives an overview of different methods that can potentially be used to determine the solubility of nanomaterials. In general, the methods presented can be broadly divided into four categories: separation methods, methods to quantify free ions, methods to quantify total dissolved

  12. 40 CFR 799.6784 - TSCA water solubility: Column elution method; shake flask method.

    Science.gov (United States)

    2010-07-01

    ... in water is a significant parameter because: (A) The spatial and temporal movement (mobility) of a... Solubility in Water of Slightly Soluble, Low Volatility Organic Substances ER15DE00.054 1 = Leveling vessel...

  13. Aging of Organic Matrices, Epoxy Resins; Causas de envejecimiento de matrices organicas. Resinas epoxidicas

    Energy Technology Data Exchange (ETDEWEB)

    Pazos, M.; Prendes, P.; Varela, M.; Paz, S. [Departamento de I mas D de Gairesa, La Coruna (Spain)

    1997-09-01

    Epoxy resins are very important polymers widely used in advance materials. Approximately 200.000 Tns/year are used in different fields such as coating, floor and paving, adhesives, composites, etc. Due to the importance of these polymers, aging studies are necessary. In this work most important aging-factors are described. We have observed that the water plays a very important role in the degradation-process. (Author)

  14. Modified gum Arabic hydrogels as matrices for controlled release of curcumin supramolecular complexes

    International Nuclear Information System (INIS)

    Gerola, Adriana P.; Silva, Danielle C.; Rubira, Adley F.; Muniz, Edvani C.

    2015-01-01

    Modified gum Arabic (GA) hydrogels show a pH-responsive behavior making them excellent matrices to be used for oral administration of drugs. Our goal is to study the behavior of those matrices in simulated gastric and intestinal fluids. In this work we will present how the methacrylation degree of GA, by using glycidyl methacrylate, can affect the properties of these hydrogels for controlled release. The drug used in this work is the curcumin (Cur). Cur is associated with numerous pharmacological activities, but their application is limited by the low water solubility. We will present some studies involving the formation of host-guest complexes between Cur and natural cyclodextrins. Both modified GA and hydrogels were characterized by different techniques. The kinetics release of Cur complex-containing modified GA hydrogels was studied to have an insight on the release mechanism and rate constants. Toxicity studies on undifferentiated and differentiated Caco-2 were also carried out. (author)

  15. Long-term modeling of glass waste in portland cement- and clay-based matrices

    International Nuclear Information System (INIS)

    Stockman, H.W.; Nagy, K.L.; Morris, C.E.

    1995-12-01

    A set of ''templates'' was developed for modeling waste glass interactions with cement-based and clay-based matrices. The templates consist of a modified thermodynamic database, and input files for the EQ3/6 reaction path code, containing embedded rate models and compositions for waste glass, cement, and several pozzolanic materials. Significant modifications were made in the thermodynamic data for Th, Pb, Ra, Ba, cement phases, and aqueous silica species. It was found that the cement-containing matrices could increase glass corrosion rates by several orders of magnitude (over matrixless or clay matrix systems), but they also offered the lowest overall solubility for Pb, Ra, Th and U. Addition of pozzolans to cement decreased calculated glass corrosion rates by up to a factor of 30. It is shown that with current modeling capabilities, the ''affinity effect'' cannot be trusted to passivate glass if nuclei are available for precipitation of secondary phases that reduce silica activity

  16. Persistence of urban organic aerosols composition: Decoding their structural complexity and seasonal variability

    International Nuclear Information System (INIS)

    Matos, João T.V.; Duarte, Regina M.B.O.; Lopes, Sónia P.; Silva, Artur M.S.; Duarte, Armando C.

    2017-01-01

    Organic Aerosols (OAs) are typically defined as highly complex matrices whose composition changes in time and space. Focusing on time vector, this work uses two-dimensional nuclear magnetic resonance (2D NMR) techniques to examine the structural features of water-soluble (WSOM) and alkaline-soluble organic matter (ASOM) sequentially extracted from fine atmospheric aerosols collected in an urban setting during cold and warm seasons. This study reveals molecular signatures not previously decoded in NMR-related studies of OAs as meaningful source markers. Although the ASOM is less hydrophilic and structurally diverse than its WSOM counterpart, both fractions feature a core with heteroatom-rich branched aliphatics from both primary (natural and anthropogenic) and secondary origin, aromatic secondary organics originated from anthropogenic aromatic precursors, as well as primary saccharides and amino sugar derivatives from biogenic emissions. These common structures represent those 2D NMR spectral signatures that are present in both seasons and can thus be seen as an “annual background” profile of the structural composition of OAs at the urban location. Lignin-derived structures, nitroaromatics, disaccharides, and anhydrosaccharides signatures were also identified in the WSOM samples only from periods identified as smoke impacted, which reflects the influence of biomass-burning sources. The NMR dataset on the H–C molecules backbone was also used to propose a semi-quantitative structural model of urban WSOM, which will aid efforts for more realistic studies relating the chemical properties of OAs with their atmospheric behavior. - Highlights: • 2D NMR spectroscopy was used to decode urban organic aerosols. • Water and alkaline soluble components of urban organic aerosols have been compared. • Persistence of urban organic aerosols composition across different seasons. • Annual background profile of the structural features of urban organic aerosols. • Semi

  17. Water-based preparation of spider silk films as drug delivery matrices.

    Science.gov (United States)

    Agostini, Elisa; Winter, Gerhard; Engert, Julia

    2015-09-10

    The main focus of this work was to obtain a drug delivery matrix characterized by biocompatibility, water insolubility and good mechanical properties. Moreover the preparation process has to be compatible with protein encapsulation and the obtained matrix should be able to sustain release a model protein. Spider silk proteins represent exceptional natural polymers due to their mechanical properties in combination with biocompatibility. As both hydrophobic and slowly biodegrading biopolymers, recombinant spider silk proteins fulfill the required properties for a drug delivery system. In this work, we present the preparation of eADF4(C16) films as drug delivery matrices without the use of any organic solvent. Water-based spider silk films were characterized in terms of protein secondary structure, thermal stability, zeta-potential, solubility, mechanical properties, and water absorption and desorption. Additionally, this study includes an evaluation of their application as a drug delivery system for both small molecular weight drugs and high molecular weight molecules such as proteins. Our investigation focused on possible improvements in the film's mechanical properties including plasticizers in the film matrix. Furthermore, different film designs were prepared, such as: monolayer, coated monolayer, multilayer (sandwich), and coated multilayer. The release of the model protein BSA from these new systems was studied. Results indicated that spider silk films are a promising protein drug delivery matrix, capable of releasing the model protein over 90 days with a release profile close to zero order kinetic. Such films could be used for several pharmaceutical and medical purposes, especially when mechanical strength of a drug eluting matrix is of high importance. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Electron spin-lattice relaxation mechanisms of radiation produced trapped electrons and hydrogen atoms in aqueous and organic glassy matrices. Modulation of electron nuclear dipolar interaction by tunnelling modes in a glassy matrix. [. gamma. rays

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, M K; Kevan, L [Wayne State Univ., Detroit, Mich. (USA). Dept. of Chemistry

    1977-01-01

    The spin lattice relaxation of trapped electrons in aqueous and organic glasses and trapped hydrogen atoms in phosphoric acid glass has been directly studied as a function of temperature by the saturation recovery method. Below 50 to 100 K, the major spin lattice relaxation mechanism involves modulation of the electron nuclear dipolar (END) interaction with nuclei in the radical's environment by tunnelling of those nuclei between two or more positions. This relaxation mechanism occurs with high efficiency and has a characteristic linear temperature dependence. The tunnelling nuclei around trapped electrons do not seem to involve the nearest neighbor nuclei which are oriented by the electron in the process of solvation. Instead the tunnelling nuclei typically appear to be next nearest neighbors to the trapped electron. The identities of the tunnelling nuclei have been deduced by isotopic substitution and are attributed to: Na in 10 mol dm/sup -3/ NaOH aqueous glass, ethyl protons in ethanol glass, methyl protons in methanol glass and methyl protons in MTHF glass. For trapped hydrogen atoms in phosphoric acid, the phosphorus nuclei appear to be the effective tunnelling nuclei. Below approximately 10 K the spin lattice relaxation is dominated by a temperature independent cross relaxation term for H atoms in phosphoric acid glass and for electrons in 10 mol dm/sup -3/ NaOH aqueous glass, but not for electrons in organic glasses. This is compared with recent electron-electron double resonance studies of cross relaxation in these glasses. The spin lattice relaxation of O/sup -/ formed in 10 mol dm/sup -3/ NaOH aqueous glass was also studied and found to be mainly dominated by a Raman process with an effective Debye temperature of about 100 K.

  19. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander; Genton, Marc G.; Sun, Ying

    2015-01-01

    We approximate large non-structured Matérn covariance matrices of size n×n in the H-matrix format with a log-linear computational cost and storage O(kn log n), where rank k ≪ n is a small integer. Applications are: spatial statistics, machine learning and image analysis, kriging and optimal design.

  20. Theoretical origin of quark mass matrices

    International Nuclear Information System (INIS)

    Mohapatra, R.N.

    1987-01-01

    This paper presents the theoretical origin of specific quark mass matrices in the grand unified theories. The author discusses the first natural derivation of the Stech-type mass matrix in unified gauge theories. A solution to the strong CP-problem is provided

  1. Malware Analysis Using Visualized Image Matrices

    Directory of Open Access Journals (Sweden)

    KyoungSoo Han

    2014-01-01

    Full Text Available This paper proposes a novel malware visual analysis method that contains not only a visualization method to convert binary files into images, but also a similarity calculation method between these images. The proposed method generates RGB-colored pixels on image matrices using the opcode sequences extracted from malware samples and calculates the similarities for the image matrices. Particularly, our proposed methods are available for packed malware samples by applying them to the execution traces extracted through dynamic analysis. When the images are generated, we can reduce the overheads by extracting the opcode sequences only from the blocks that include the instructions related to staple behaviors such as functions and application programming interface (API calls. In addition, we propose a technique that generates a representative image for each malware family in order to reduce the number of comparisons for the classification of unknown samples and the colored pixel information in the image matrices is used to calculate the similarities between the images. Our experimental results show that the image matrices of malware can effectively be used to classify malware families both statically and dynamically with accuracy of 0.9896 and 0.9732, respectively.

  2. Moment matrices, border bases and radical computation

    NARCIS (Netherlands)

    B. Mourrain; J.B. Lasserre; M. Laurent (Monique); P. Rostalski; P. Trebuchet (Philippe)

    2013-01-01

    htmlabstractIn this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming it complex (resp. real) variety is nte. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and

  3. Moment matrices, border bases and radical computation

    NARCIS (Netherlands)

    Lasserre, J.B.; Laurent, M.; Mourrain, B.; Rostalski, P.; Trébuchet, P.

    2013-01-01

    In this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming its complex (resp. real) variety is finite. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and semi-definite

  4. Moment matrices, border bases and radical computation

    NARCIS (Netherlands)

    B. Mourrain; J.B. Lasserre; M. Laurent (Monique); P. Rostalski; P. Trebuchet (Philippe)

    2011-01-01

    htmlabstractIn this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming it complex (resp. real) variety is nte. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and

  5. Malware analysis using visualized image matrices.

    Science.gov (United States)

    Han, KyoungSoo; Kang, BooJoong; Im, Eul Gyu

    2014-01-01

    This paper proposes a novel malware visual analysis method that contains not only a visualization method to convert binary files into images, but also a similarity calculation method between these images. The proposed method generates RGB-colored pixels on image matrices using the opcode sequences extracted from malware samples and calculates the similarities for the image matrices. Particularly, our proposed methods are available for packed malware samples by applying them to the execution traces extracted through dynamic analysis. When the images are generated, we can reduce the overheads by extracting the opcode sequences only from the blocks that include the instructions related to staple behaviors such as functions and application programming interface (API) calls. In addition, we propose a technique that generates a representative image for each malware family in order to reduce the number of comparisons for the classification of unknown samples and the colored pixel information in the image matrices is used to calculate the similarities between the images. Our experimental results show that the image matrices of malware can effectively be used to classify malware families both statically and dynamically with accuracy of 0.9896 and 0.9732, respectively.

  6. Generation speed in Raven's Progressive Matrices Test

    NARCIS (Netherlands)

    Verguts, T.; Boeck, P. De; Maris, E.G.G.

    1999-01-01

    In this paper, we investigate the role of response fluency on a well-known intelligence test, Raven's (1962) Advanced Progressive Matrices (APM) test. Critical in solving this test is finding rules that govern the items. Response fluency is conceptualized as generation speed or the speed at which a

  7. Inversion of General Cyclic Heptadiagonal Matrices

    Directory of Open Access Journals (Sweden)

    A. A. Karawia

    2013-01-01

    Full Text Available We describe a reliable symbolic computational algorithm for inverting general cyclic heptadiagonal matrices by using parallel computing along with recursion. The computational cost of it is operations. The algorithm is implementable to the Computer Algebra System (CAS such as MAPLE, MATLAB, and MATHEMATICA. Two examples are presented for the sake of illustration.

  8. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander

    2015-11-30

    We approximate large non-structured Matérn covariance matrices of size n×n in the H-matrix format with a log-linear computational cost and storage O(kn log n), where rank k ≪ n is a small integer. Applications are: spatial statistics, machine learning and image analysis, kriging and optimal design.

  9. Dry season aerosol iron solubility in tropical northern Australia

    Directory of Open Access Journals (Sweden)

    V. H. L. Winton

    2016-10-01

    Full Text Available Marine nitrogen fixation is co-limited by the supply of iron (Fe and phosphorus in large regions of the global ocean. The deposition of soluble aerosol Fe can initiate nitrogen fixation and trigger toxic algal blooms in nitrate-poor tropical waters. We present dry season soluble Fe data from the Savannah Fires in the Early Dry Season (SAFIRED campaign in northern Australia that reflects coincident dust and biomass burning sources of soluble aerosol Fe. The mean soluble and total aerosol Fe concentrations were 40 and 500 ng m−3 respectively. Our results show that while biomass burning species may not be a direct source of soluble Fe, biomass burning may substantially enhance the solubility of mineral dust. We observed fractional Fe solubility up to 12 % in mixed aerosols. Thus, Fe in dust may be more soluble in the tropics compared to higher latitudes due to higher concentrations of biomass-burning-derived reactive organic species in the atmosphere. In addition, biomass-burning-derived particles can act as a surface for aerosol Fe to bind during atmospheric transport and subsequently be released to the ocean upon deposition. As the aerosol loading is dominated by biomass burning emissions over the tropical waters in the dry season, additions of biomass-burning-derived soluble Fe could have harmful consequences for initiating nitrogen-fixing toxic algal blooms. Future research is required to quantify biomass-burning-derived particle sources of soluble Fe over tropical waters.

  10. A framework for API solubility modelling

    DEFF Research Database (Denmark)

    Conte, Elisa; Gani, Rafiqul; Crafts, Peter

    . In addition, most of the models are not predictive and requires experimental data for the calculation of the needed parameters. This work aims at developing an efficient framework for the solubility modelling of Active Pharmaceutical Ingredients (API) in water and organic solvents. With this framework......-SAFT) are used for solubility calculations when the needed interaction parameters or experimental data are available. The CI-UNIFAC is instead used when the previous models lack interaction parameters or when solubility data are not available. A new GC+ model for APIs solvent selection based...... on the hydrophobicity, hydrophilicity and polarity information of the API and solvent is also developed, for performing fast solvent selection and screening. Eventually, all the previous developments are integrated in a framework for their efficient and integrated use. Two case studies are presented: the first...

  11. Effects of aqueous-soluble organic compounds on the removal of selected radionuclides from high-level waste part I: Distribution of Sr, Cs, and Tc onto 18 absorbers from an irradiated, organic-containing leachate simulant for Hanford Tank 101-SY

    International Nuclear Information System (INIS)

    Marsh, S.F.; Svitra, Z.V.; Bowen, S.M.

    1995-01-01

    Many of the radioactive waste storage tanks at U.S. Department of Energy facilities contain organic compounds that have been degraded by radiolysis and chemical reactions. In this investigation, we measured the effect of some aqueous-soluble organic compounds on the sorption of strontium, cesium, and technetium onto 18 absorbers that offer high sorption of strontium from organic-free solutions. For our test solution we used a leachate from a simulated slurry for Hanford Tank 101-SY that initially contained ethylenediaminetetraacetic acid (EDTA) and then was gamma-irradiated to 34 Mrads. We measured distribution coefficients (Kds) for each element/absorber combination for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. To facilitate comparisons, we include Kd values for these same element/absorber combinations from three organic-free simulant solutions. The Kd values for strontium sorption from the simulant that contained the degraded organics usually decreased by large factors, whereas the Kd values for cesium and technetium sorption were relatively unaffected

  12. Uranyl Oxalate Solubility

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G.; Costenoble, S.; Grandjean, S. [CEA Marcoule DEN/DRCP/SCPS/LCA - BP17171 - 30207 Bagnols sur Ceze cedex (France)

    2008-07-01

    The solubility of uranyl oxalate was determined at ambient temperature by precipitation in oxalic-nitric solutions, using an initial uranyl concentration of 0.1 mol/L. Oxalic concentration varied from 0.075 to 0.3 mol/L while nitric concentration ranged between 0.75 and 3 mol/L. Dissolution tests, using complementary oxalic-nitric media, were carried out for 550 hours in order to study the kinetic to reach thermodynamic equilibrium. Similar solubility values were reached by dissolution and precipitation. Using the results, it was possible to draw the solubility surface versus oxalic and nitric concentrations and to determine both the apparent solubility constant of UO{sub 2}C{sub 2}O{sub 4}, 3H{sub 2}O (Ks) and the apparent formation constant of the first uranyl-oxalate complex UO{sub 2}C{sub 2}O{sub 4} (log {beta}1), for ionic strengths varying between 1 and 3 mol/L. Ks and log {beta}1 values were found to vary from 1.9 10{sup -8} to 9.2 10{sup -9} and from 5.95 to 6.06, respectively, when ionic strength varied from 1 to 3 mol/L. A second model may fit our data obtained at an ionic strength of 3 mol/L suggesting as reported by Moskvin et al. (1959) that no complexes are formed for [H{sup +}] at 3 M. The Ks value would then be 1.3 10{sup -8}. (authors)

  13. Mixed-mode chromatographic matrices for the resolution of transfer ribonucleic acids

    NARCIS (Netherlands)

    Bischoff, Rainer; Mclaughlin, L.W.

    1984-01-01

    Modification of approximately 65% of the amine groups of an aminopropylsilyl bonded-phase silica high-performance liquid chromatographic anion exchanger (APS-Hypersil) with organic acids containing n-alkyl moieties of different chain lengths, results in mixed mode chromatographic matrices of varying

  14. A role for archaeal organisms in development of atherosclerotic vulnerable plaques and myxoid matrices Um papel para organismos de arqueia no desenvolvimento de placas ateroscleróticas vulner��veis e matriz mixomatosa

    Directory of Open Access Journals (Sweden)

    Maria L Higuchi

    2006-10-01

    Full Text Available PURPOSE: Vulnerable plaques are characterized by a myxoid matrix, necrotic lipidic core, reactive oxygen species, and high levels of microorganisms. Aerobic microbes such as Chlamydophila pneumoniae and Mycoplasma pneumoniae usually do not survive in oxidative stress media. Archaea are anaerobic microbes with powerful anti-oxidative enzymes that allow detoxification of free radicals whose presence might favor the survival of aerobic microorganisms. We searched for archaeal organisms in vulnerable plaques, and possible associations with myxoid matrix, chlamydia, and mycoplasma bodies. METHODS: Twenty-nine tissue samples from 13 coronary artherectomies from large excentric ostial or bifurcational lesions were studied using optical and electron microscopy. Infectious agents compatible with archaea, chlamydia, and mycoplasma were semiquantified using electron micrographs and correlated with the amounts of fibromuscular tissue, myxoid matrix, and foam cells, as determined from semi-thin sections. Six of the cases were also submitted to polymerase chain reaction with archaeal primers. RESULTS: All 13 specimens showed archaeal-compatible structures and chlamydial and mycoplasmal bodies in at least 1 sample. There was a positive correlation between extent of the of myxoid matrix and archaeal bodies (r = 0.44, P = 0.02; between archaeal and mycoplasmal bodies (r = 0.41, P = 0.03, and between chlamydial bodies and foam cells (r = 0.42; P = 0.03. The PCR test was positive for archaeal DNA in 4 of the 6 fragments. DISCUSSION: DNA and forms suggestive of archaea are present in vulnerable plaques and may have a fundamental role in the proliferation of mycoplasma and chlamydia. This seems to be the first description of apparently pathogenic archaea in human internal organ lesions.PROPOSTA: Placas vulneráveis são caracterizadas por matriz mixomatosa, centro lipídico necrótico, espécies reativas de oxigênio e alto níveis de microorganismos. Micróbios aer

  15. Argon solubility in liquid steel

    NARCIS (Netherlands)

    Boom, R; Dankert, O; Van Veen, A; Kamperman, AA

    2000-01-01

    Experiments have been performed to establish the solubility of argon in liquid interstitial-free steel. The solubility appears to be lower than 0.1 at ppb, The results are in line with argon solubilities reported in the literature on liquid iron. Semiempirical theories and calculations based on the

  16. Experimentally probing topological order and its breakdown through modular matrices

    Science.gov (United States)

    Luo, Zhihuang; Li, Jun; Li, Zhaokai; Hung, Ling-Yan; Wan, Yidun; Peng, Xinhua; Du, Jiangfeng

    2018-02-01

    The modern concept of phases of matter has undergone tremendous developments since the first observation of topologically ordered states in fractional quantum Hall systems in the 1980s. In this paper, we explore the following question: in principle, how much detail of the physics of topological orders can be observed using state of the art technologies? We find that using surprisingly little data, namely the toric code Hamiltonian in the presence of generic disorders and detuning from its exactly solvable point, the modular matrices--characterizing anyonic statistics that are some of the most fundamental fingerprints of topological orders--can be reconstructed with very good accuracy solely by experimental means. This is an experimental realization of these fundamental signatures of a topological order, a test of their robustness against perturbations, and a proof of principle--that current technologies have attained the precision to identify phases of matter and, as such, probe an extended region of phase space around the soluble point before its breakdown. Given the special role of anyonic statistics in quantum computation, our work promises myriad applications both in probing and realistically harnessing these exotic phases of matter.

  17. On Skew Circulant Type Matrices Involving Any Continuous Fibonacci Numbers

    Directory of Open Access Journals (Sweden)

    Zhaolin Jiang

    2014-01-01

    inverse matrices of them by constructing the transformation matrices. Furthermore, the maximum column sum matrix norm, the spectral norm, the Euclidean (or Frobenius norm, and the maximum row sum matrix norm and bounds for the spread of these matrices are given, respectively.

  18. Fungible Correlation Matrices: A Method for Generating Nonsingular, Singular, and Improper Correlation Matrices for Monte Carlo Research.

    Science.gov (United States)

    Waller, Niels G

    2016-01-01

    For a fixed set of standardized regression coefficients and a fixed coefficient of determination (R-squared), an infinite number of predictor correlation matrices will satisfy the implied quadratic form. I call such matrices fungible correlation matrices. In this article, I describe an algorithm for generating positive definite (PD), positive semidefinite (PSD), or indefinite (ID) fungible correlation matrices that have a random or fixed smallest eigenvalue. The underlying equations of this algorithm are reviewed from both algebraic and geometric perspectives. Two simulation studies illustrate that fungible correlation matrices can be profitably used in Monte Carlo research. The first study uses PD fungible correlation matrices to compare penalized regression algorithms. The second study uses ID fungible correlation matrices to compare matrix-smoothing algorithms. R code for generating fungible correlation matrices is presented in the supplemental materials.

  19. Evolutionary Games with Randomly Changing Payoff Matrices

    Science.gov (United States)

    Yakushkina, Tatiana; Saakian, David B.; Bratus, Alexander; Hu, Chin-Kun

    2015-06-01

    Evolutionary games are used in various fields stretching from economics to biology. In most of these games a constant payoff matrix is assumed, although some works also consider dynamic payoff matrices. In this article we assume a possibility of switching the system between two regimes with different sets of payoff matrices. Potentially such a model can qualitatively describe the development of bacterial or cancer cells with a mutator gene present. A finite population evolutionary game is studied. The model describes the simplest version of annealed disorder in the payoff matrix and is exactly solvable at the large population limit. We analyze the dynamics of the model, and derive the equations for both the maximum and the variance of the distribution using the Hamilton-Jacobi equation formalism.

  20. An algorithmic characterization of P-matricity

    OpenAIRE

    Ben Gharbia , Ibtihel; Gilbert , Jean Charles

    2013-01-01

    International audience; It is shown that a matrix M is a P-matrix if and only if, whatever is the vector q, the Newton-min algorithm does not cycle between two points when it is used to solve the linear complementarity problem 0 ≤ x ⊥ (Mx+q) ≥ 0.; Nous montrons dans cet article qu'une matrice M est une P-matrice si, et seulement si, quel que soit le vecteur q, l'algorithme de Newton-min ne fait pas de cycle de deux points lorsqu'il est utilisé pour résoudre le problème de compl\\émentarité lin...

  1. Teaching Fourier optics through ray matrices

    International Nuclear Information System (INIS)

    Moreno, I; Sanchez-Lopez, M M; Ferreira, C; Davis, J A; Mateos, F

    2005-01-01

    In this work we examine the use of ray-transfer matrices for teaching and for deriving some topics in a Fourier optics course, exploiting the mathematical simplicity of ray matrices compared to diffraction integrals. A simple analysis of the physical meaning of the elements of the ray matrix provides a fast derivation of the conditions to obtain the optical Fourier transform. We extend this derivation to fractional Fourier transform optical systems, and derive the order of the transform from the ray matrix. Some examples are provided to stress this point of view, both with classical and with graded index lenses. This formulation cannot replace the complete explanation of Fourier optics provided by the wave theory, but it is a complementary tool useful to simplify many aspects of Fourier optics and to relate them to geometrical optics

  2. The recurrence sequences via Sylvester matrices

    Science.gov (United States)

    Karaduman, Erdal; Deveci, Ömür

    2017-07-01

    In this work, we define the Pell-Jacobsthal-Slyvester sequence and the Jacobsthal-Pell-Slyvester sequence by using the Slyvester matrices which are obtained from the characteristic polynomials of the Pell and Jacobsthal sequences and then, we study the sequences defined modulo m. Also, we obtain the cyclic groups and the semigroups from the generating matrices of these sequences when read modulo m and then, we derive the relationships among the orders of the cyclic groups and the periods of the sequences. Furthermore, we redefine Pell-Jacobsthal-Slyvester sequence and the Jacobsthal-Pell-Slyvester sequence by means of the elements of the groups and then, we examine them in the finite groups.

  3. Graph run-length matrices for histopathological image segmentation.

    Science.gov (United States)

    Tosun, Akif Burak; Gunduz-Demir, Cigdem

    2011-03-01

    The histopathological examination of tissue specimens is essential for cancer diagnosis and grading. However, this examination is subject to a considerable amount of observer variability as it mainly relies on visual interpretation of pathologists. To alleviate this problem, it is very important to develop computational quantitative tools, for which image segmentation constitutes the core step. In this paper, we introduce an effective and robust algorithm for the segmentation of histopathological tissue images. This algorithm incorporates the background knowledge of the tissue organization into segmentation. For this purpose, it quantifies spatial relations of cytological tissue components by constructing a graph and uses this graph to define new texture features for image segmentation. This new texture definition makes use of the idea of gray-level run-length matrices. However, it considers the runs of cytological components on a graph to form a matrix, instead of considering the runs of pixel intensities. Working with colon tissue images, our experiments demonstrate that the texture features extracted from "graph run-length matrices" lead to high segmentation accuracies, also providing a reasonable number of segmented regions. Compared with four other segmentation algorithms, the results show that the proposed algorithm is more effective in histopathological image segmentation.

  4. Joint Matrices Decompositions and Blind Source Separation

    Czech Academy of Sciences Publication Activity Database

    Chabriel, G.; Kleinsteuber, M.; Moreau, E.; Shen, H.; Tichavský, Petr; Yeredor, A.

    2014-01-01

    Roč. 31, č. 3 (2014), s. 34-43 ISSN 1053-5888 R&D Projects: GA ČR GA102/09/1278 Institutional support: RVO:67985556 Keywords : joint matrices decomposition * tensor decomposition * blind source separation Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 5.852, year: 2014 http://library.utia.cas.cz/separaty/2014/SI/tichavsky-0427607.pdf

  5. Tensor Permutation Matrices in Finite Dimensions

    OpenAIRE

    Christian, Rakotonirina

    2005-01-01

    We have generalised the properties with the tensor product, of one 4x4 matrix which is a permutation matrix, and we call a tensor commutation matrix. Tensor commutation matrices can be constructed with or without calculus. A formula allows us to construct a tensor permutation matrix, which is a generalisation of tensor commutation matrix, has been established. The expression of an element of a tensor commutation matrix has been generalised in the case of any element of a tensor permutation ma...

  6. Fast Approximate Joint Diagonalization Incorporating Weight Matrices

    Czech Academy of Sciences Publication Activity Database

    Tichavský, Petr; Yeredor, A.

    2009-01-01

    Roč. 57, č. 3 (2009), s. 878-891 ISSN 1053-587X R&D Projects: GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : autoregressive processes * blind source separation * nonstationary random processes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.212, year: 2009 http://library.utia.cas.cz/separaty/2009/SI/tichavsky-fast approximate joint diagonalization incorporating weight matrices.pdf

  7. Photoluminescence of nanocrystals embedded in oxide matrices

    International Nuclear Information System (INIS)

    Estrada, C.; Gonzalez, J.A.; Kunold, A.; Reyes-Esqueda, J.A.; Pereyra, P.

    2006-12-01

    We used the theory of finite periodic systems to explain the photoluminescence spectra dependence on the average diameter of nanocrystals embedded in oxide matrices. Because of the broad matrix band gap, the photoluminescence response is basically determined by isolated nanocrystals and sequences of a few of them. With this model we were able to reproduce the shape and displacement of the experimentally observed photoluminescence spectra. (author)

  8. Equiangular tight frames and unistochastic matrices

    Czech Academy of Sciences Publication Activity Database

    Goyeneche, D.; Turek, Ondřej

    2017-01-01

    Roč. 50, č. 24 (2017), č. článku 245304. ISSN 1751-8113 R&D Projects: GA ČR GA17-01706S Institutional support: RVO:61389005 Keywords : equiangular tight frames * unistochastic matrices * SIC POVM Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 1.857, year: 2016

  9. Simplifications of rational matrices by using UML

    OpenAIRE

    Tasić, Milan B.; Stanimirović, Ivan P.

    2013-01-01

    The simplification process on rational matrices consists of simplifying each entry represented by a rational function. We follow the classic approach of dividing the numerator and denominator polynomials by their common GCD polynomial, and provide the activity diagram in UML for this process. A rational matrix representation as the quotient of a polynomial matrix and a polynomial is also discussed here and illustrated via activity diagrams. Also, a class diagram giving the links between the c...

  10. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander

    2015-01-07

    We approximate large non-structured covariance matrices in the H-matrix format with a log-linear computational cost and storage O(n log n). We compute inverse, Cholesky decomposition and determinant in H-format. As an example we consider the class of Matern covariance functions, which are very popular in spatial statistics, geostatistics, machine learning and image analysis. Applications are: kriging and optimal design

  11. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander

    2015-01-05

    We approximate large non-structured covariance matrices in the H-matrix format with a log-linear computational cost and storage O(nlogn). We compute inverse, Cholesky decomposition and determinant in H-format. As an example we consider the class of Matern covariance functions, which are very popular in spatial statistics, geostatistics, machine learning and image analysis. Applications are: kriging and op- timal design.

  12. PHAGOCYTOSIS AND REMODELING OF COLLAGEN MATRICES

    OpenAIRE

    Abraham, Leah C.; Dice, J Fred.; Lee, Kyongbum; Kaplan, David L.

    2007-01-01

    The biodegradation of collagen and the deposition of new collagen-based extracellular matrices are of central importance in tissue remodeling and function. Similarly, for collagen-based biomaterials used in tissue engineering, the degradation of collagen scaffolds with accompanying cellular infiltration and generation of new extracellular matrix is critical for integration of in vitro grown tissues in vivo. In earlier studies we observed significant impact of collagen structure on primary lun...

  13. Preconditioners for regularized saddle point matrices

    Czech Academy of Sciences Publication Activity Database

    Axelsson, Owe

    2011-01-01

    Roč. 19, č. 2 (2011), s. 91-112 ISSN 1570-2820 Institutional research plan: CEZ:AV0Z30860518 Keywords : saddle point matrices * preconditioning * regularization * eigenvalue clustering Subject RIV: BA - General Mathematics Impact factor: 0.533, year: 2011 http://www.degruyter.com/view/j/jnma.2011.19.issue-2/jnum.2011.005/jnum.2011.005. xml

  14. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander; Genton, Marc G.; Sun, Ying; Tempone, Raul

    2015-01-01

    We approximate large non-structured covariance matrices in the H-matrix format with a log-linear computational cost and storage O(n log n). We compute inverse, Cholesky decomposition and determinant in H-format. As an example we consider the class of Matern covariance functions, which are very popular in spatial statistics, geostatistics, machine learning and image analysis. Applications are: kriging and optimal design

  15. Hierarchical matrix approximation of large covariance matrices

    KAUST Repository

    Litvinenko, Alexander; Genton, Marc G.; Sun, Ying; Tempone, Raul

    2015-01-01

    We approximate large non-structured covariance matrices in the H-matrix format with a log-linear computational cost and storage O(nlogn). We compute inverse, Cholesky decomposition and determinant in H-format. As an example we consider the class of Matern covariance functions, which are very popular in spatial statistics, geostatistics, machine learning and image analysis. Applications are: kriging and op- timal design.

  16. Characteristics of phosphorus adsorption by sediment mineral matrices with different particle sizes

    Directory of Open Access Journals (Sweden)

    Yang Xiao

    2013-07-01

    Full Text Available The particle size of sediment is one of the main factors that influence the phosphorus physical adsorption on sediment. In order to eliminate the effect of other components of sediment on the phosphorus physical adsorption the sediment mineral matrices were obtained by removing inorganic matter metal oxides, and organic matter from natural sediments, which were collected from the Nantong reach of the Yangtze River. The results show that an exponential relationship exists between the median particle size (D50 and specific surface area (Sg of the sediment mineral matrices, and the fine sediment mineral matrix sample has a larger specific surface area and pore volume than the coarse sediment particles. The kinetic equations were used to describe the phosphorus adsorption process of the sediment mineral matrices, including the Elovich equation, quasi-first-order adsorption kinetic equation, and quasi-second-order adsorption kinetic equation. The results show that the quasi-second-order adsorption kinetic equation has the best fitting effect. Using the mass conservation and Langmuir adsorption kinetic equations, a formula was deduced to calculate the equilibrium adsorption capacity of the sediment mineral matrices. The results of this study show that the phosphorus adsorption capacity decreases with the increase of D50, indicating that the specific surface area and pore volume are the main factors in determining the phosphorus adsorption capacity of the sediment mineral matrices. This study will help understand the important role of sediment in the transformation of phosphorus in aquatic environments.

  17. Chitosan-Based Matrices Prepared by Gamma Irradiation for Tissue Regeneration: Structural Properties vs. Preparation Method.

    Science.gov (United States)

    Casimiro, Maria Helena; Lancastre, Joana J H; Rodrigues, Alexandra P; Gomes, Susana R; Rodrigues, Gabriela; Ferreira, Luís M

    2017-02-01

    In the last decade, new generations of biopolymer-based materials have attracted attention, aiming its application as scaffolds for tissue engineering. These engineered three-dimensional scaffolds are designed to improve or replace damaged, missing, or otherwise compromised tissues or organs. Despite the number of promising methods that can be used to generate 3D cell-instructive matrices, the innovative nature of the present work relies on the application of ionizing radiation technology to form and modify surfaces and matrices with advantage over more conventional technologies (room temperature reaction, absence of harmful initiators or solvents, high penetration through the bulk materials, etc.), and the possibility of preparation and sterilization in one single step. The current chapter summarizes the work done by the authors in the gamma radiation processing of biocompatible and biodegradable chitosan-based matrices for skin regeneration. Particular attention is given to the correlation between the different preparation conditions and the final polymeric matrices' properties. We therefore expect to demonstrate that instructive matrices produced and improved by radiation technology bring to the field of skin regenerative medicine a supplemental advantage over more conservative techniques.

  18. Group inverses of M-matrices and their applications

    CERN Document Server

    Kirkland, Stephen J

    2013-01-01

    Group inverses for singular M-matrices are useful tools not only in matrix analysis, but also in the analysis of stochastic processes, graph theory, electrical networks, and demographic models. Group Inverses of M-Matrices and Their Applications highlights the importance and utility of the group inverses of M-matrices in several application areas. After introducing sample problems associated with Leslie matrices and stochastic matrices, the authors develop the basic algebraic and spectral properties of the group inverse of a general matrix. They then derive formulas for derivatives of matrix f

  19. Deterministic matrices matching the compressed sensing phase transitions of Gaussian random matrices

    Science.gov (United States)

    Monajemi, Hatef; Jafarpour, Sina; Gavish, Matan; Donoho, David L.; Ambikasaran, Sivaram; Bacallado, Sergio; Bharadia, Dinesh; Chen, Yuxin; Choi, Young; Chowdhury, Mainak; Chowdhury, Soham; Damle, Anil; Fithian, Will; Goetz, Georges; Grosenick, Logan; Gross, Sam; Hills, Gage; Hornstein, Michael; Lakkam, Milinda; Lee, Jason; Li, Jian; Liu, Linxi; Sing-Long, Carlos; Marx, Mike; Mittal, Akshay; Monajemi, Hatef; No, Albert; Omrani, Reza; Pekelis, Leonid; Qin, Junjie; Raines, Kevin; Ryu, Ernest; Saxe, Andrew; Shi, Dai; Siilats, Keith; Strauss, David; Tang, Gary; Wang, Chaojun; Zhou, Zoey; Zhu, Zhen

    2013-01-01

    In compressed sensing, one takes samples of an N-dimensional vector using an matrix A, obtaining undersampled measurements . For random matrices with independent standard Gaussian entries, it is known that, when is k-sparse, there is a precisely determined phase transition: for a certain region in the (,)-phase diagram, convex optimization typically finds the sparsest solution, whereas outside that region, it typically fails. It has been shown empirically that the same property—with the same phase transition location—holds for a wide range of non-Gaussian random matrix ensembles. We report extensive experiments showing that the Gaussian phase transition also describes numerous deterministic matrices, including Spikes and Sines, Spikes and Noiselets, Paley Frames, Delsarte-Goethals Frames, Chirp Sensing Matrices, and Grassmannian Frames. Namely, for each of these deterministic matrices in turn, for a typical k-sparse object, we observe that convex optimization is successful over a region of the phase diagram that coincides with the region known for Gaussian random matrices. Our experiments considered coefficients constrained to for four different sets , and the results establish our finding for each of the four associated phase transitions. PMID:23277588

  20. Soluble polymer conjugates for drug delivery.

    Science.gov (United States)

    Minko, Tamara

    2005-01-01

    The use of water-soluble polymeric conjugates as drug carriers offers several possible advantages. These advantages include: (1) improved drug pharmacokinetics; (2) decreased toxicity to healthy organs; (3) possible facilitation of accumulation and preferential uptake by targeted cells; (4) programmed profile of drug release. In this review, we will consider the main types of useful polymeric conjugates and their role and effectiveness as carriers in drug delivery systems.: © 2005 Elsevier Ltd . All rights reserved.

  1. Hydration-Induced Phase Separation in Amphiphilic Polymer Matrices and its Influence on Voclosporin Release

    Energy Technology Data Exchange (ETDEWEB)

    Khan, I. John [The State Univ. of New Jersey, Piscataway, NJ (United States); Murthy, N. Sanjeeva [The State Univ. of New Jersey, Piscataway, NJ (United States); Kohn, Joachim [The State Univ. of New Jersey, Piscataway, NJ (United States)

    2015-10-30

    Voclosporin is a highly potent, new cyclosporine -- a derivative that is currently in Phase 3 clinical trials in the USA as a potential treatment for inflammatory diseases of the eye. Voclosporin represents a number of very sparingly soluble drugs that are difficult to administer. It was selected as a model drug that is dispersed within amphiphilic polymer matrices, and investigated the changing morphology of the matrices using neutron and x-ray scattering during voclosporin release and polymer resorption. The hydrophobic segments of the amphiphilic polymer chain are comprised of desaminotyrosyl-tyrosine ethyl ester (DTE) and desaminotyrosyl-tyrosine (DT), and the hydrophilic component is poly(ethylene glycol) (PEG). Water uptake in these matrices resulted in the phase separation of hydrophobic and hydrophilic domains that are a few hundred Angstroms apart. These water-driven morphological changes influenced the release profile of voclosporin and facilitated a burst-free release from the polymer. No such morphological reorganization was observed in poly(lactide-co-glycolide) (PLGA), which exhibits an extended lag period, followed by a burst-like release of voclosporin when the polymer was degraded. An understanding of the effect of polymer composition on the hydration behavior is central to understanding and controlling the phase behavior and resorption characteristics of the matrix for achieving long-term controlled release of hydrophobic drugs such as voclosporin.

  2. Hydration-Induced Phase Separation in Amphiphilic Polymer Matrices and its Influence on Voclosporin Release

    Directory of Open Access Journals (Sweden)

    Joachim Kohn

    2012-10-01

    Full Text Available Voclosporin is a highly potent, new cyclosporine-A derivative that is currently in Phase 3 clinical trials in the USA as a potential treatment for inflammatory diseases of the eye. Voclosporin represents a number of very sparingly soluble drugs that are difficult to administer. We therefore selected it as a model drug that is dispersed within amphiphilic polymer matrices, and investigated the changing morphology of the matrices using neutron and x-ray scattering during voclosporin release and polymer resorption. The hydrophobic segments of the amphiphilic polymer chain are comprised of desaminotyrosyl-tyrosine ethyl ester (DTE and desaminotyrosyl-tyrosine (DT, and the hydrophilic component is poly(ethylene glycol (PEG. Water uptake in these matrices resulted in the phase separation of hydrophobic and hydrophilic domains that are a few hundred Angstroms apart. These water-driven morphological changes influenced the release profile of voclosporin and facilitated a burst-free release from the polymer. No such morphological reorganization was observed in poly(lactide-co-glycolide (PLGA, which exhibits an extended lag period, followed by a burst-like release of voclosporin when the polymer was degraded. An understanding of the effect of polymer composition on the hydration behavior is central to understanding and controlling the phase behavior and resorption characteristics of the matrix for achieving long-term controlled release of hydrophobic drugs such as voclosporin.

  3. Immobilisation of radwaste in cement based matrices

    International Nuclear Information System (INIS)

    Glasser, F.P.; Macphee, D.; Atkins, M.; Pointer, C.; Cowie, J.; Wilding, C.R.; Mattingley, N.J.; Evans, P.A.

    1989-01-01

    The solubilities and influence on cement pH are reported for calcium aluminate and aluminosulphate hydrates. The solubility of Ca(OH) 2 is reported to 700 bars. Polymerization of C-S-H is investigated by NMR. Specific interactions of U 6+ and iodine (I - , IO 3 - ) with cement components are described. The impact of radiation on cements and the influence of higher temperature are documented. The role of dissolved Ca and CO 2 in groundwaters as dissolution media for cements are reported. (author)

  4. Uranium and thorium phosphate based matrices; syntheses, characterizations and lixiviation

    International Nuclear Information System (INIS)

    Dacheux, N.

    1995-03-01

    In the framework of the search for a ceramic material usable in the radioactive waste storage, uranium and thorium phosphates have been investigated. Their experimental synthesis conditions have been entirely reviewed, they lead to the preparation of four new compounds: U(UO 2 )(PO 4 ) 2 , U 2 O(PO 4 ) 2 , UC1PO 4 ,H 2 O, and Th 4 (PO 4 ) 4 , U 2 O 3 P 2 O 7 and Th 3 (PO 4 ) 4 . Characterization by several techniques (X-rays and neutron powder diffractions, UV-Visible and Infra-red spectroscopies, XPS,...) were performed. The ab initio structure determination of U(UO 2 )(PO 4 ) 2 has been achieved by X-rays and refined by neutron diffractions. Through its physico-chemical analysis, we found that this compound was a new mixed valence uranium phosphate in which U 4+ and UO 2 2+ ions are ordered in pairs along parallel chains according to a new type of arrangement. Reaction mechanism, starting from UC1PO 4 , 4H 2 O and based on redox processes of uranium in solid state was set up. From two main matrices U(UO 2 )(PO 4 ) 2 and Th 4 (PO 4 ) 4 P 2 O 7 , solid solutions were studied. They consist of replacement of U(IV) by Th(IV) and reversely. The leaching tests on pure, loaded and doped matrices were performed in terms of storage time, pH of solutions, and determined by the use of solids labelled with 230 U or by the measurement of uranyl concentration by Laser-Induced Time-Resolved Spectrofluorometry. Average concentration of uranium in the liquid phase is around 10 -4 M to 10 -6 M. Taking into account the very low solubilities of the studied phosphate ceramics, we estimated their chemical performances promising as an answer to the important nuclear waste problem, if we compare them to the glasses used at the present time. (author). 47 figs., 23 tabs., 6 appendixes

  5. Reversible, reagentless solubility changes in phosphatidylcholine-stabilized gold nanoparticles

    International Nuclear Information System (INIS)

    Mackiewicz, Marilyn R; Ayres, Benjamin R; Reed, Scott M

    2008-01-01

    Phosphatidylcholine (PC) is a versatile ligand for synthesizing gold nanoparticles that are soluble in either organic or aqueous media. Here we report a novel route to organic-soluble, PC-stabilized gold nanoparticles that can be re-suspended in water after removal of the organic solvent. Similarly, we show that PC-stabilized gold nanoparticles synthesized in water can be re-suspended in organic solvents after complete removal of water. Without complete removal of the solvent, the nanoparticles retain their original solubility and do not phase transfer. This change in solvent preference from organic to aqueous and vice versa without the use of an additional phase transfer reagent is novel, visually striking, and of utility for synthetic modification of nanoparticles. This approach allows chemical reactions to be performed on nanoparticles in organic solvents followed by conversion of the products to water-soluble materials. A narrow distribution of PC-stabilized gold nanoparticles was obtained after phase transfer to water as characterized by UV-visible (UV-vis) spectroscopy and transmission electron microscopy (TEM), demonstrating that the narrow distribution obtained from the organic synthesis is retained after transfer to water. This method produces water-soluble nanoparticles with a narrower dispersity than is possible with direct aqueous synthesis

  6. Organics.

    Science.gov (United States)

    Chian, Edward S. K.; DeWalle, Foppe B.

    1978-01-01

    Presents water analysis literature for 1978. This review is concerned with organics, and it covers: (1) detergents and surfactants; (2) aliphatic and aromatic hydrocarbons; (3) pesticides and chlorinated hydrocarbons; and (4) naturally occurring organics. A list of 208 references is also presented. (HM)

  7. Organizers.

    Science.gov (United States)

    Callison, Daniel

    2000-01-01

    Focuses on "organizers," tools or techniques that provide identification and classification along with possible relationships or connections among ideas, concepts, and issues. Discusses David Ausubel's research and ideas concerning advance organizers; the implications of Ausubel's theory to curriculum and teaching; "webbing," a…

  8. Determination of coefficient matrices for ARMA model

    International Nuclear Information System (INIS)

    Tran Dinh Tri.

    1990-10-01

    A new recursive algorithm for determining coefficient matrices of ARMA model from measured data is presented. The Yule-Walker equations for the case of ARMA model are derived from the ARMA innovation equation. The recursive algorithm is based on choosing appropriate form of the operator functions and suitable representation of the (n+1)-th order operator functions according to ones with the lower order. Two cases, when the order of the AR part is equal to one of the MA part, and the optimal case, were considered. (author) 5 refs

  9. Algebraic Graph Theory Morphisms, Monoids and Matrices

    CERN Document Server

    Knauer, Ulrich

    2011-01-01

    This is a highly self-contained book about algebraic graph theory which iswritten with a view to keep the lively and unconventional atmosphere of a spoken text to communicate the enthusiasm the author feels about this subject. The focus is on homomorphisms and endomorphisms, matrices and eigenvalues. Graph models are extremely useful for almost all applications and applicators as they play an important role as structuring tools. They allow to model net structures -like roads, computers, telephones -instances of abstract data structures -likelists, stacks, trees -and functional or object orient

  10. Coherence and extensions of stochastic matrices

    Directory of Open Access Journals (Sweden)

    Angelo Gilio

    1995-11-01

    Full Text Available In this paper a review of some general results on coherence of conditional probability assessments is given. Then, a necessary and sufficient condition on coherence of two finite families of discrete conditianal probability distributions, represented by two stochastic matrices P and Q, is obtained. Moreover, the possible extensions of the assessment (P,Q to the marginal distributions are examined and explicit formulas for them are given in some special case. Finally, a general algorithm to check coherence of (P,Q and to derive its extensions is proposed.

  11. 2D gravity and random matrices

    International Nuclear Information System (INIS)

    Zinn-Justin, J.

    1990-01-01

    Recent progress in 2D gravity coupled to d ≤ 1 matter, based on a representation of discrete gravity in terms of random matrices, is reported. The matrix problem can be solved in many cases by the introduction of suitable orthogonal polynomials. Alternatively in the continuum limit the orthogonal polynomial method can be shown to be equivalent to the construction of representation of the canonical commutation relations in terms of differential operators. In the case of pure gravity or discrete Ising-like matter the sum over topologies is reduced to the solution of non-linear differential equations. The d = 1 problem can be solved by semiclassical methods

  12. Spectroscopy, modeling and computation of metal chelate solubility in supercritical CO2. 1998 annual progress report

    International Nuclear Information System (INIS)

    Brennecke, J.F.; Chateauneuf, J.E.; Stadtherr, M.A.

    1998-01-01

    'This report summarizes work after 1 year and 8 months (9/15/96-5/14/98) of a 3 year project. Thus far, progress has been made in: (1) the measurement of the solubility of metal chelates in SC CO 2 with and without added cosolvents, (2) the spectroscopic determination of preferential solvation of metal chelates by cosolvents in SC CO 2 solutions, and (3) the development of a totally reliable computational technique for phase equilibrium computations. An important factor in the removal of metals from solid matrices with CO 2 /chelate mixtures is the equilibrium solubility of the metal chelate complex in the CO 2 .'

  13. Solubility of cefoxitin acid in different solvent systems

    International Nuclear Information System (INIS)

    Yuan, Fuhong; Wang, Yongli; Xiao, Liping; Huang, Qiaoyin; Xu, Jinchao; Jiang, Chen; Hao, Hongxun

    2016-01-01

    Highlights: • The solubility of cefoxitin acid in different solvent systems was measured. • Three models were used to correlate the solubility data. • The dissolution enthalpy of the dissolution process was calculated. - Abstract: Cefoxitin acid is one kind of important pharmaceutical intermediate. Its solubility is crucial for designing and optimizing the crystallization processes. In this work, the solubility of cefoxitin acid in organic solvents (methanol, acetonitrile, ethanol, isopropanol, n-propanol and ethyl acetate), water and water-methanol mixtures was measured spectrophotometrically using a shake-flask method within the temperature range 278.15–303.15 K. PXRD data and the Karl Fischer method were used to verify the crystal form stability of cefoxitin acid in the solubility measuring process. The melting points, the enthalpy and entropy of fusion were estimated. Results showed that the solubility of cefoxitin acid increases with the increasing temperature in all tested solvents in this work, and the solubility of cefoxitin acid increases with the increasing methanol concentration in water-methanol mixtures. The experimental solubility values were well correlated using the modified Apelblat equation, NRTL model and CNIBS/R-K model. An equation proposed by Williamson was adopted to calculate the molar enthalpy during the dissolution process.

  14. Removal of soluble toxic metals from water

    International Nuclear Information System (INIS)

    Buckley, L.P.; Vijayan, S.; McConeghy, G.J.; Maves, S.R.; Martin, J.F.

    1990-05-01

    The removal of selected, soluble toxic metals from aqueous solutions has been accomplished using a combination of chemical treatment and ultrafiltration. The process has been evaluated at the bench-scale and is undergoing pilot-scale testing. Removal efficiencies in excess of 95-99% have been realized. The test program at the bench-scale investigated the limitations and established the optimum range of operating parameters for the process, while the tests conducted with the pilot-scale process equipment are providing information on longer-term process efficiencies, effective processing rates, and fouling potential of the membranes. With the typically found average concentrations of the toxic metals in groundwaters at Superfund sites used as the feed solution, the process has decreased levels up to 100-fold or more. Experiments were also conducted with concentrated solutions to determine their release from silica-based matrices. The solidified wastes were subjected to EP Toxicity test procedures and met the criteria successfully. The final phase of the program involving a field demonstration at a uranium tailings site will be outlined

  15. Soluble Molecularly Imprinted Nanorods for Homogeneous Molecular Recognition

    Directory of Open Access Journals (Sweden)

    Rongning Liang

    2018-03-01

    Full Text Available Nowadays, it is still difficult for molecularly imprinted polymers (MIPs to achieve homogeneous recognition since they cannot be easily dissolved in organic or aqueous phase. To address this issue, soluble molecularly imprinted nanorods have been synthesized by using soluble polyaniline doped with a functionalized organic protonic acid as the polymer matrix. By employing 1-naphthoic acid as a model, the proposed imprinted nanorods exhibit an excellent solubility and good homogeneous recognition ability. The imprinting factor for the soluble imprinted nanoroads is 6.8. The equilibrium dissociation constant and the apparent maximum number of the proposed imprinted nanorods are 248.5 μM and 22.1 μmol/g, respectively. We believe that such imprinted nanorods may provide an appealing substitute for natural receptors in homogeneous recognition related fields.

  16. Soluble Molecularly Imprinted Nanorods for Homogeneous Molecular Recognition

    Science.gov (United States)

    Liang, Rongning; Wang, Tiantian; Zhang, Huan; Yao, Ruiqing; Qin, Wei

    2018-03-01

    Nowadays, it is still difficult for molecularly imprinted polymer (MIPs) to achieve homogeneous recognition since they cannot be easily dissolved in organic or aqueous phase. To address this issue, soluble molecularly imprinted nanorods have been synthesized by using soluble polyaniline doped with a functionalized organic protonic acid as the polymer matrix. By employing 1-naphthoic acid as a model, the proposed imprinted nanorods exhibit an excellent solubility and good homogeneous recognition ability. The imprinting factor for the soluble imprinted nanoroads is 6.8. The equilibrium dissociation constant and the apparent maximum number of the proposed imprinted nanorods are 248.5 μM and 22.1 μmol/g, respectively. We believe that such imprinted nanorods may provide an appealing substitute for natural receptors in homogeneous recognition related fields.

  17. Eletroquímica de latossolos brasileiros após a remoção da matéria orgânica humificada solúvel Eletrochemistry of Brazilian oxisols after removal of soluble organic matter

    Directory of Open Access Journals (Sweden)

    Leonardo Barros Dobbss

    2008-06-01

    Full Text Available A eletroquímica e a concentração de matéria orgânica nos horizontes superficiais de Latossolos correlacionam-se estreitamente. No presente trabalho, avaliaram-se as propriedades eletroquímicas do horizonte superficial de sete Latossolos brasileiros após a remoção das substâncias húmicas em meio alcalino. Os solos foram separados em dois grupos, segundo sua mineralogia, caulinítica e oxídica. O extrator NaOH 0,1 mol L-1 solubilizou substâncias húmicas correspondentes a menos de 3 % da MO total, indicando forte adsorção específica do material orgânico à fração mineral. A extração de ácidos húmicos e fúlvicos foi capaz de inverter o sinal de carga da superfície; no entanto, o efeito mais acentuado da retirada das substâncias húmicas solúveis foi a perda da capacidade-tampão das cargas do solo. A capacidade da dupla camada elétrica, uma medida indireta desse poder-tampão, aumentou de 3 a 15 vezes depois da extração das substâncias húmicas alcalino-solúveis. Solos com mineralogia predominantemente oxídica apresentaram maiores valores do ponto de efeito salino nulo, da capacidade da dupla camada elétrica, além da diminuição na capacidade de troca de cátions do que aqueles de natureza caulinítica.Electrochemistry and organic matter concentrations in the surface horizons of Oxisols are closely related. This study evaluated the electrochemical properties in the surface horizon of seven Brazilian Oxisols after the removal of humic substances by alkaline extraction. Based on their mineralogy the soils were grouped as kaolinitic or oxidic. Less than 3 % of the total organic matter were soluble humic substances extractable by NaOH 0.1 mol L-1, indicating their strong specific adsorption to the inorganic mineral sites. The removal of the humic and fulvic acids reversed the soil surface charge and also led to a marked loss in the buffering capacity of the soil charge. The electric double layer capacity, an indirect

  18. Frequency filtering decompositions for unsymmetric matrices and matrices with strongly varying coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, C.

    1996-12-31

    In 1992, Wittum introduced the frequency filtering decompositions (FFD), which yield a fast method for the iterative solution of large systems of linear equations. Based on this method, the tangential frequency filtering decompositions (TFFD) have been developed. The TFFD allow the robust and efficient treatment of matrices with strongly varying coefficients. The existence and the convergence of the TFFD can be shown for symmetric and positive definite matrices. For a large class of matrices, it is possible to prove that the convergence rate of the TFFD and of the FFD is independent of the number of unknowns. For both methods, schemes for the construction of frequency filtering decompositions for unsymmetric matrices have been developed. Since, in contrast to Wittums`s FFD, the TFFD needs only one test vector, an adaptive test vector can be used. The TFFD with respect to the adaptive test vector can be combined with other iterative methods, e.g. multi-grid methods, in order to improve the robustness of these methods. The frequency filtering decompositions have been successfully applied to the problem of the decontamination of a heterogeneous porous medium by flushing.

  19. Organizations

    DEFF Research Database (Denmark)

    Hatch, Mary Jo

    and considers many more. Mary Jo Hatch introduces the concept of organizations by presenting definitions and ideas drawn from the a variety of subject areas including the physical sciences, economics, sociology, psychology, anthropology, literature, and the visual and performing arts. Drawing on examples from......Most of us recognize that organizations are everywhere. You meet them on every street corner in the form of families and shops, study in them, work for them, buy from them, pay taxes to them. But have you given much thought to where they came from, what they are today, and what they might become...... prehistory and everyday life, from the animal kingdom as well as from business, government, and other formal organizations, Hatch provides a lively and thought provoking introduction to the process of organization....

  20. Water-soluble vitamins.

    Science.gov (United States)

    Konings, Erik J M

    2006-01-01

    Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were based on, for example, LC. Koontz et al. showed results of total folate concentrations measured by microbiological assay in a variety of foods. Samples were submitted in a routine manner to experienced laboratories that regularly perform folate analysis fee-for-service basis in the United States. Each laboratory reported the use of a microbiological method similar to the AOAC Official Method for the determination of folic acid. Striking was, the use of 3 different pH extraction conditions by 4 laboratories. Only one laboratory reported using a tri-enzyme extraction. Results were evaluated. Results for folic acid fortified foods had considerably lower between-laboratory variation, 9-11%, versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. One should realize a large variation in results, which might be caused by slight modifications in the microbiological analysis of total folate in foods or the analysis in various (unfortified) food matrixes. Furthermore, optimal

  1. Critical statistics for non-Hermitian matrices

    International Nuclear Information System (INIS)

    Garcia-Garcia, A.M.; Verbaarschot, J.J.M.; Nishigaki, S.M.

    2002-01-01

    We introduce a generalized ensemble of non-Hermitian matrices interpolating between the Gaussian Unitary Ensemble, the Ginibre ensemble, and the Poisson ensemble. The joint eigenvalue distribution of this model is obtained by means of an extension of the Itzykson-Zuber formula to general complex matrices. Its correlation functions are studied both in the case of weak non-Hermiticity and in the case of strong non-Hermiticity. In the weak non-Hermiticity limit we show that the spectral correlations in the bulk of the spectrum display critical statistics: the asymptotic linear behavior of the number variance is already approached for energy differences of the order of the eigenvalue spacing. To lowest order, its slope does not depend on the degree of non-Hermiticity. Close the edge, the spectral correlations are similar to the Hermitian case. In the strong non-Hermiticity limit the crossover behavior from the Ginibre ensemble to the Poisson ensemble first appears close to the surface of the spectrum. Our model may be relevant for the description of the spectral correlations of an open disordered system close to an Anderson transition

  2. Tensor Dictionary Learning for Positive Definite Matrices.

    Science.gov (United States)

    Sivalingam, Ravishankar; Boley, Daniel; Morellas, Vassilios; Papanikolopoulos, Nikolaos

    2015-11-01

    Sparse models have proven to be extremely successful in image processing and computer vision. However, a majority of the effort has been focused on sparse representation of vectors and low-rank models for general matrices. The success of sparse modeling, along with popularity of region covariances, has inspired the development of sparse coding approaches for these positive definite descriptors. While in earlier work, the dictionary was formed from all, or a random subset of, the training signals, it is clearly advantageous to learn a concise dictionary from the entire training set. In this paper, we propose a novel approach for dictionary learning over positive definite matrices. The dictionary is learned by alternating minimization between sparse coding and dictionary update stages, and different atom update methods are described. A discriminative version of the dictionary learning approach is also proposed, which simultaneously learns dictionaries for different classes in classification or clustering. Experimental results demonstrate the advantage of learning dictionaries from data both from reconstruction and classification viewpoints. Finally, a software library is presented comprising C++ binaries for all the positive definite sparse coding and dictionary learning approaches presented here.

  3. Virial expansion for almost diagonal random matrices

    International Nuclear Information System (INIS)

    Yevtushenko, Oleg; Kravtsov, Vladimir E

    2003-01-01

    Energy level statistics of Hermitian random matrices H-circumflex with Gaussian independent random entries H i≥j is studied for a generic ensemble of almost diagonal random matrices with (vertical bar H ii vertical bar 2 ) ∼ 1 and (vertical bar H i≠j vertical bar 2 ) bF(vertical bar i - j vertical bar) parallel 1. We perform a regular expansion of the spectral form-factor K(τ) = 1 + bK 1 (τ) + b 2 K 2 (τ) + c in powers of b parallel 1 with the coefficients K m (τ) that take into account interaction of (m + 1) energy levels. To calculate K m (τ), we develop a diagrammatic technique which is based on the Trotter formula and on the combinatorial problem of graph edges colouring with (m + 1) colours. Expressions for K 1 (τ) and K 2 (τ) in terms of infinite series are found for a generic function F(vertical bar i - j vertical bar ) in the Gaussian orthogonal ensemble (GOE), the Gaussian unitary ensemble (GUE) and in the crossover between them (the almost unitary Gaussian ensemble). The Rosenzweig-Porter and power-law banded matrix ensembles are considered as examples

  4. Generalized Eigenvalues for pairs on heritian matrices

    Science.gov (United States)

    Rublein, George

    1988-01-01

    A study was made of certain special cases of a generalized eigenvalue problem. Let A and B be nxn matrics. One may construct a certain polynomial, P(A,B, lambda) which specializes to the characteristic polynomial of B when A equals I. In particular, when B is hermitian, that characteristic polynomial, P(I,B, lambda) has real roots, and one can ask: are the roots of P(A,B, lambda) real when B is hermitian. We consider the case where A is positive definite and show that when N equals 3, the roots are indeed real. The basic tools needed in the proof are Shur's theorem on majorization for eigenvalues of hermitian matrices and the interlacing theorem for the eigenvalues of a positive definite hermitian matrix and one of its principal (n-1)x(n-1) minors. The method of proof first reduces the general problem to one where the diagonal of B has a certain structure: either diag (B) = diag (1,1,1) or diag (1,1,-1), or else the 2 x 2 principal minors of B are all 1. According as B has one of these three structures, we use an appropriate method to replace A by a positive diagonal matrix. Since it can be easily verified that P(D,B, lambda) has real roots, the result follows. For other configurations of B, a scaling and a continuity argument are used to prove the result in general.

  5. Students’ misconceptions on solubility equilibrium

    Science.gov (United States)

    Setiowati, H.; Utomo, S. B.; Ashadi

    2018-05-01

    This study investigated the students’ misconceptions of the solubility equilibrium. The participants of the study consisted of 164 students who were in the science class of second year high school. Instrument used is two-tier diagnostic test consisting of 15 items. Responses were marked and coded into four categories: understanding, misconception, understand little without misconception, and not understanding. Semi-structured interviews were carried out with 45 students according to their written responses which reflected different perspectives, to obtain a more elaborated source of data. Data collected from multiple methods were analyzed qualitatively and quantitatively. Based on the data analysis showed that the students misconceptions in all areas in solubility equilibrium. They had more misconceptions such as in the relation of solubility and solubility product, common-ion effect and pH in solubility, and precipitation concept.

  6. On the americium oxalate solubility

    International Nuclear Information System (INIS)

    Zakolupin, S.A.; Korablin, Eh.V.

    1977-01-01

    The americium oxalate solubility at different nitric (0.0-1 M) and oxalic (0.0-0.4 M) acid concentrations was investigated in the temperature range from 14 to 60 deg C. The dependence of americium oxalate solubility on the oxalic acid concentration was determined. Increasing oxalic acid concentration was found to reduce the americium oxalate solubility. The dependence of americium oxalate solubility on the oxalic acid concentration was noted to be a minimum at low acidity (0.1-0.3 M nitric acid). This is most likely due to Am(C 2 O 4 ) + , Am(C 2 O 4 ) 2 - and Am(C 2 O 4 ) 3 3- complex ion formation which have different unstability constants. On the basis of the data obtained, a preliminary estimate was carried out for the product of americium oxalate solubility in nitric acid medium (10 -29 -10 -31 ) and of the one in water (6.4x10 -20 )

  7. Meet and Join Matrices in the Poset of Exponential Divisors

    Indian Academy of Sciences (India)

    ... exponential divisor ( G C E D ) and the least common exponential multiple ( L C E M ) do not always exist. In this paper we embed this poset in a lattice. As an application we study the G C E D and L C E M matrices, analogues of G C D and L C M matrices, which are both special cases of meet and join matrices on lattices.

  8. The 'golden' matrices and a new kind of cryptography

    International Nuclear Information System (INIS)

    Stakhov, A.P.

    2007-01-01

    We consider a new class of square matrices called the 'golden' matrices. They are a generalization of the classical Fibonacci Q-matrix for continuous domain. The 'golden' matrices can be used for creation of a new kind of cryptography called the 'golden' cryptography. The method is very fast and simple for technical realization and can be used for cryptographic protection of digital signals (telecommunication and measurement systems)

  9. Generalized Perron--Frobenius Theorem for Nonsquare Matrices

    OpenAIRE

    Avin, Chen; Borokhovich, Michael; Haddad, Yoram; Kantor, Erez; Lotker, Zvi; Parter, Merav; Peleg, David

    2013-01-01

    The celebrated Perron--Frobenius (PF) theorem is stated for irreducible nonnegative square matrices, and provides a simple characterization of their eigenvectors and eigenvalues. The importance of this theorem stems from the fact that eigenvalue problems on such matrices arise in many fields of science and engineering, including dynamical systems theory, economics, statistics and optimization. However, many real-life scenarios give rise to nonsquare matrices. A natural question is whether the...

  10. Intrinsic Density Matrices of the Nuclear Shell Model

    International Nuclear Information System (INIS)

    Deveikis, A.; Kamuntavichius, G.

    1996-01-01

    A new method for calculation of shell model intrinsic density matrices, defined as two-particle density matrices integrated over the centre-of-mass position vector of two last particles and complemented with isospin variables, has been developed. The intrinsic density matrices obtained are completely antisymmetric, translation-invariant, and do not employ a group-theoretical classification of antisymmetric states. They are used for exact realistic density matrix expansion within the framework of the reduced Hamiltonian method. The procedures based on precise arithmetic for calculation of the intrinsic density matrices that involve no numerical diagonalization or orthogonalization have been developed and implemented in the computer code. (author). 11 refs., 2 tabs

  11. Noisy covariance matrices and portfolio optimization II

    Science.gov (United States)

    Pafka, Szilárd; Kondor, Imre

    2003-03-01

    Recent studies inspired by results from random matrix theory (Galluccio et al.: Physica A 259 (1998) 449; Laloux et al.: Phys. Rev. Lett. 83 (1999) 1467; Risk 12 (3) (1999) 69; Plerou et al.: Phys. Rev. Lett. 83 (1999) 1471) found that covariance matrices determined from empirical financial time series appear to contain such a high amount of noise that their structure can essentially be regarded as random. This seems, however, to be in contradiction with the fundamental role played by covariance matrices in finance, which constitute the pillars of modern investment theory and have also gained industry-wide applications in risk management. Our paper is an attempt to resolve this embarrassing paradox. The key observation is that the effect of noise strongly depends on the ratio r= n/ T, where n is the size of the portfolio and T the length of the available time series. On the basis of numerical experiments and analytic results for some toy portfolio models we show that for relatively large values of r (e.g. 0.6) noise does, indeed, have the pronounced effect suggested by Galluccio et al. (1998), Laloux et al. (1999) and Plerou et al. (1999) and illustrated later by Laloux et al. (Int. J. Theor. Appl. Finance 3 (2000) 391), Plerou et al. (Phys. Rev. E, e-print cond-mat/0108023) and Rosenow et al. (Europhys. Lett., e-print cond-mat/0111537) in a portfolio optimization context, while for smaller r (around 0.2 or below), the error due to noise drops to acceptable levels. Since the length of available time series is for obvious reasons limited in any practical application, any bound imposed on the noise-induced error translates into a bound on the size of the portfolio. In a related set of experiments we find that the effect of noise depends also on whether the problem arises in asset allocation or in a risk measurement context: if covariance matrices are used simply for measuring the risk of portfolios with a fixed composition rather than as inputs to optimization, the

  12. Nanoencapsulation of OPAA With Mesoporous Materials for Chemical Agent Decontamination in Organic Solvents

    National Research Council Canada - National Science Library

    Ong, K. K; Dong, H; Wei, Y; Cheng, T-c; Yin, R

    2003-01-01

    .... The enzyme activity in different matrices was evaluated in various organic solvents. Significant activities were retained in most of these matrices, particularly in the presence of acetone and dimethyl formamide...

  13. Equiangular tight frames and unistochastic matrices

    International Nuclear Information System (INIS)

    Goyeneche, Dardo; Turek, Ondřej

    2017-01-01

    We demonstrate that a complex equiangular tight frame composed of N vectors in dimension d , denoted ETF ( d , N ), exists if and only if a certain bistochastic matrix, univocally determined by N and d , belongs to a special class of unistochastic matrices. This connection allows us to find new complex ETFs in infinitely many dimensions and to derive a method to introduce non-trivial free parameters in ETFs. We present an explicit six-parametric family of complex ETF(6,16), which defines a family of symmetric POVMs. Minimal and maximal possible average entanglement of the vectors within this qubit–qutrit family are described. Furthermore, we propose an efficient numerical procedure to compute the unitary matrix underlying a unistochastic matrix, which we apply to find all existing classes of complex ETFs containing up to 20 vectors. (paper)

  14. Colonization of bone matrices by cellular components

    Science.gov (United States)

    Shchelkunova, E. I.; Voropaeva, A. A.; Korel, A. V.; Mayer, D. A.; Podorognaya, V. T.; Kirilova, I. A.

    2017-09-01

    Practical surgery, traumatology, orthopedics, and oncology require bioengineered constructs suitable for replacement of large-area bone defects. Only rigid/elastic matrix containing recipient's bone cells capable of mitosis, differentiation, and synthesizing extracellular matrix that supports cell viability can comply with these requirements. Therefore, the development of the techniques to produce structural and functional substitutes, whose three-dimensional structure corresponds to the recipient's damaged tissues, is the main objective of tissue engineering. This is achieved by developing tissue-engineering constructs represented by cells placed on the matrices. Low effectiveness of carrier matrix colonization with cells and their uneven distribution is one of the major problems in cell culture on various matrixes. In vitro studies of the interactions between cells and material, as well as the development of new techniques for scaffold colonization by cellular components are required to solve this problem.

  15. Computing with linear equations and matrices

    International Nuclear Information System (INIS)

    Churchhouse, R.F.

    1983-01-01

    Systems of linear equations and matrices arise in many disciplines. The equations may accurately represent conditions satisfied by a system or, more likely, provide an approximation to a more complex system of non-linear or differential equations. The system may involve a few or many thousand unknowns and each individual equation may involve few or many of them. Over the past 50 years a vast literature on methods for solving systems of linear equations and the associated problems of finding the inverse or eigenvalues of a matrix has been produced. These lectures cover those methods which have been found to be most useful for dealing with such types of problem. References are given where appropriate and attention is drawn to the possibility of improved methods for use on vector and parallel processors. (orig.)

  16. Matrices over runtime systems at exascale

    KAUST Repository

    Agullo, Emmanuel

    2012-11-01

    The goal of Matrices Over Runtime Systems at Exascale (MORSE) project is to design dense and sparse linear algebra methods that achieve the fastest possible time to an accurate solution on large-scale multicore systems with GPU accelerators, using all the processing power that future high end systems can make available. In this poster, we propose a framework for describing linear algebra algorithms at a high level of abstraction and delegating the actual execution to a runtime system in order to design software whose performance is portable accross architectures. We illustrate our methodology on three classes of problems: dense linear algebra, sparse direct methods and fast multipole methods. The resulting codes have been incorporated into Magma, Pastix and ScalFMM solvers, respectively. © 2012 IEEE.

  17. Sparse random matrices: The eigenvalue spectrum revisited

    International Nuclear Information System (INIS)

    Semerjian, Guilhem; Cugliandolo, Leticia F.

    2003-08-01

    We revisit the derivation of the density of states of sparse random matrices. We derive a recursion relation that allows one to compute the spectrum of the matrix of incidence for finite trees that determines completely the low concentration limit. Using the iterative scheme introduced by Biroli and Monasson [J. Phys. A 32, L255 (1999)] we find an approximate expression for the density of states expected to hold exactly in the opposite limit of large but finite concentration. The combination of the two methods yields a very simple geometric interpretation of the tails of the spectrum. We test the analytic results with numerical simulations and we suggest an indirect numerical method to explore the tails of the spectrum. (author)

  18. From Pauli Matrices to Quantum Ito Formula

    International Nuclear Information System (INIS)

    Pautrat, Yan

    2005-01-01

    This paper answers important questions raised by the recent description, by Attal, of a robust and explicit method to approximate basic objects of quantum stochastic calculus on bosonic Fock space by analogues on the state space of quantum spin chains. The existence of that method justifies a detailed investigation of discrete-time quantum stochastic calculus. Here we fully define and study that theory and obtain in particular a discrete-time quantum Ito formula, which one can see as summarizing the commutation relations of Pauli matrices.An apparent flaw in that approximation method is the difference in the quantum Ito formulas, discrete and continuous, which suggests that the discrete quantum stochastic calculus differs fundamentally from the continuous one and is therefore not a suitable object to approximate subtle phenomena. We show that flaw is only apparent by proving that the continuous-time quantum Ito formula is actually a consequence of its discrete-time counterpart

  19. Uranium solubility and solubility controls in selected Needle's Eye groundwaters

    International Nuclear Information System (INIS)

    Falck, W.E.; Hooker, P.J.

    1991-01-01

    The solubility control of uranium in selected groundwater samples from the cliff and sediments at the Needle's Eye natural analogue site is investigated using the speciation code PHREEQE and the CHEMVAL thermodynamic database (release 3). Alkali-earth bearing uranyl carbonate secondary minerals are likely to exert influence on the solubility . Other candidates are UO 2 and arsenates, depending on the prevailing redox conditions. In the absence of literature data, solubility products for important arsenates have been estimated from analogy with other arsenates and phosphates. Phosphates themselves are unlikely to exert control owing to their comparatively high solubilities. The influence of seawater flooding into the sediments is also discussed. The importance of uranyl arsenates in the retardation of uranium in shallow sediments has been demonstrated in theory, but there are some significant gaps in the thermodynamic databases used. (author)

  20. Dirac matrices for Chern-Simons gravity

    Energy Technology Data Exchange (ETDEWEB)

    Izaurieta, Fernando; Ramirez, Ricardo; Rodriguez, Eduardo [Departamento de Matematica y Fisica Aplicadas, Universidad Catolica de la Santisima Concepcion, Alonso de Ribera 2850, 4090541 Concepcion (Chile)

    2012-10-06

    A genuine gauge theory for the Poincare, de Sitter or anti-de Sitter algebras can be constructed in (2n- 1)-dimensional spacetime by means of the Chern-Simons form, yielding a gravitational theory that differs from General Relativity but shares many of its properties, such as second order field equations for the metric. The particular form of the Lagrangian is determined by a rank n, symmetric tensor invariant under the relevant algebra. In practice, the calculation of this invariant tensor can be reduced to the computation of the trace of the symmetrized product of n Dirac Gamma matrices {Gamma}{sub ab} in 2n-dimensional spacetime. While straightforward in principle, this calculation can become extremely cumbersome in practice. For large enough n, existing computer algebra packages take an inordinate long time to produce the answer or plainly fail having used up all available memory. In this talk we show that the general formula for the trace of the symmetrized product of 2n Gamma matrices {Gamma}{sub ab} can be written as a certain sum over the integer partitions s of n, with every term being multiplied by a numerical cofficient {alpha}{sub s}. We then give a general algorithm that computes the {alpha}-coefficients as the solution of a linear system of equations generated by evaluating the general formula for different sets of tensors B{sup ab} with random numerical entries. A recurrence relation between different coefficients is shown to hold and is used in a second, 'minimal' algorithm to greatly speed up the computations. Runtime of the minimal algorithm stays below 1 min on a typical desktop computer for up to n = 25, which easily covers all foreseeable applications of the trace formula.

  1. Viscous hydrophilic injection matrices for serial crystallography

    Directory of Open Access Journals (Sweden)

    Gabriela Kovácsová

    2017-07-01

    Full Text Available Serial (femtosecond crystallography at synchrotron and X-ray free-electron laser (XFEL sources distributes the absorbed radiation dose over all crystals used for data collection and therefore allows measurement of radiation damage prone systems, including the use of microcrystals for room-temperature measurements. Serial crystallography relies on fast and efficient exchange of crystals upon X-ray exposure, which can be achieved using a variety of methods, including various injection techniques. The latter vary significantly in their flow rates – gas dynamic virtual nozzle based injectors provide very thin fast-flowing jets, whereas high-viscosity extrusion injectors produce much thicker streams with flow rates two to three orders of magnitude lower. High-viscosity extrusion results in much lower sample consumption, as its sample delivery speed is commensurate both with typical XFEL repetition rates and with data acquisition rates at synchrotron sources. An obvious viscous injection medium is lipidic cubic phase (LCP as it is used for in meso membrane protein crystallization. However, LCP has limited compatibility with many crystallization conditions. While a few other viscous media have been described in the literature, there is an ongoing need to identify additional injection media for crystal embedding. Critical attributes are reliable injection properties and a broad chemical compatibility to accommodate samples as heterogeneous and sensitive as protein crystals. Here, the use of two novel hydrogels as viscous injection matrices is described, namely sodium carboxymethyl cellulose and the thermo-reversible block polymer Pluronic F-127. Both are compatible with various crystallization conditions and yield acceptable X-ray background. The stability and velocity of the extruded stream were also analysed and the dependence of the stream velocity on the flow rate was measured. In contrast with previously characterized injection media, both new

  2. Noble gases solubility in water

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  3. THE DYNAMICS OF THE MATRICS STRUCTURE

    OpenAIRE

    Dumitru CONSTANTINESCU

    2007-01-01

    The relationships organization-suppliers-customers have recently known major changes in the structure of services and have made the organization develop its managerial and professional competencies in order to do projects. The qualified organization is the most trust-worthy in the process of doing a project. The participation of an organization in doing projects depends on a multitude of factors. Out of these factors, the structural organization comes forth, as it represents the variable with...

  4. Deterministic matrices matching the compressed sensing phase transitions of Gaussian random matrices

    OpenAIRE

    Monajemi, Hatef; Jafarpour, Sina; Gavish, Matan; Donoho, David L.; Ambikasaran, Sivaram; Bacallado, Sergio; Bharadia, Dinesh; Chen, Yuxin; Choi, Young; Chowdhury, Mainak; Chowdhury, Soham; Damle, Anil; Fithian, Will; Goetz, Georges; Grosenick, Logan

    2012-01-01

    In compressed sensing, one takes samples of an N-dimensional vector using an matrix A, obtaining undersampled measurements . For random matrices with independent standard Gaussian entries, it is known that, when is k-sparse, there is a precisely determined phase transition: for a certain region in the (,)-phase diagram, convex optimization typically finds the sparsest solution, whereas outside that region, it typically fails. It has been shown empirically that the same property—with the ...

  5. Soluble fullerene derivatives : The effect of electronic structure on transistor performance and air stability

    NARCIS (Netherlands)

    Ball, James M.; Bouwer, Ricardo K.M.; Kooistra, Floris B.; Frost, Jarvist M.; Qi, Yabing; Buchaca Domingo, Ester; Smith, Jeremy; de Leeuw, Dago M.; Hummelen, Jan C.; Nelson, Jenny; Kahn, Antoine; Stingelin, Natalie; Bradley, Donal D.C.; Anthopoulos, Thomas D.

    2011-01-01

    The family of soluble fullerene derivatives comprises a widely studied group of electron transporting molecules for use in organic electronic and optoelectronic devices. For electronic applications, electron transporting (n-channel) materials are required for implementation into organic

  6. Binary Positive Semidefinite Matrices and Associated Integer Polytopes

    DEFF Research Database (Denmark)

    Letchford, Adam N.; Sørensen, Michael Malmros

    2012-01-01

    We consider the positive semidefinite (psd) matrices with binary entries, along with the corresponding integer polytopes. We begin by establishing some basic properties of these matrices and polytopes. Then, we show that several families of integer polytopes in the literature-the cut, boolean qua...

  7. CONVERGENCE OF POWERS OF CONTROLLABLE INTUITIONISTIC FUZZY MATRICES

    OpenAIRE

    Riyaz Ahmad Padder; P. Murugadas

    2016-01-01

    Convergences of powers of controllable intuitionistic fuzzy matrices have been stud¬ied. It is shown that they oscillate with period equal to 2, in general. Some equalities and sequences of inequalities about powers of controllable intuitionistic fuzzy matrices have been obtained.

  8. Propositional matrices as alternative representation of truth values ...

    African Journals Online (AJOL)

    The paper considered the subject of representation of truth values in symbolic logic. An alternative representation was given based on the rows and columns properties of matrices, with the operations involving the logical connectives subjected to the laws of algebra of propositions. Matrices of various propositions detailing ...

  9. The Modern Origin of Matrices and Their Applications

    Science.gov (United States)

    Debnath, L.

    2014-01-01

    This paper deals with the modern development of matrices, linear transformations, quadratic forms and their applications to geometry and mechanics, eigenvalues, eigenvectors and characteristic equations with applications. Included are the representations of real and complex numbers, and quaternions by matrices, and isomorphism in order to show…

  10. Abel-grassmann's groupoids of modulo matrices

    International Nuclear Information System (INIS)

    Javaid, Q.; Awan, M.D.; Naqvi, S.H.A.

    2016-01-01

    The binary operation of usual addition is associative in all matrices over R. However, a binary operation of addition in matrices over Z/sub n/ of a nonassociative structures of AG-groupoids and AG-groups are defined and investigated here. It is shown that both these structures exist for every integer n >≥ 3. Various properties of these structures are explored like: (i) Every AG-groupoid of matrices over Z/sub n/ is transitively commutative AG-groupoid and is a cancellative AG-groupoid if n is prime. (ii) Every AG-groupoid of matrices over Z/sub n/ of Type-II is a T/sup 3/-AG-groupoid. (iii) An AG-groupoid of matrices over Z/sub n/ ; G /sub nAG/(t,u), is an AG-band, if t+u=1(mod n). (author)

  11. Xenogenic extracellular matrices as potential biomaterials for interposition grafting in urological surgery.

    LENUS (Irish Health Repository)

    Davis, N F

    2012-01-31

    PURPOSE: The field of tissue engineering focuses on developing strategies for reconstructing injured, diseased, and congenitally absent tissues and organs. During the last decade urologists have benefited from remodeling and regenerative properties of bioscaffolds derived from xenogenic extracellular matrices. We comprehensively reviewed the current literature on structural and functional characteristics of xenogenic extracellular matrix grafting since it was first described in urological surgery. We also reviewed the clinical limitations, and assessed the potential for safe and effective urological application of extracellular matrix grafting in place of autogenous tissue. MATERIALS AND METHODS: We performed literature searches for English language publications using the PubMed(R) and MEDLINE(R) databases. Keywords included "xenogenic," "extracellular matrix" and "genitourinary tract applications." A total of 112 articles were scrutinized, of which 50 were suitable for review based on clinical relevance and importance of content. RESULTS: Since the mid 1990s xenogenic extracellular matrices have been used to successfully treat a number of pathological conditions that affect the upper and lower genitourinary tract. They are typically prepared from porcine organs such as small intestine and bladder. These organs are harvested and subjected to decellularization and sterilization techniques before surgical implantation. Bioinductive growth factors that are retained during the preparation process induce constructive tissue remodeling as the extracellular matrix is simultaneously degraded and excreted. However, recent documented concerns over durability, decreased mechanical strength and residual porcine DNA after preparation techniques have temporarily hampered the potential of extracellular matrices as a reliable replacement for genitourinary tract structures. CONCLUSIONS: Extracellular matrices are a useful alternative for successfully treating a number of urological

  12. Pure Phase Solubility Limits: LANL

    International Nuclear Information System (INIS)

    C. Stockman

    2001-01-01

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO 2 partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility products

  13. Pure Phase Solubility Limits: LANL

    Energy Technology Data Exchange (ETDEWEB)

    C. Stockman

    2001-01-26

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO{sub 2} partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility

  14. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  15. Substituted amylose matrices for oral drug delivery

    International Nuclear Information System (INIS)

    Moghadam, S H; Wang, H W; El-Leithy, E Saddar; Chebli, C; Cartilier, L

    2007-01-01

    High amylose corn starch was used to obtain substituted amylose (SA) polymers by chemically modifying hydroxyl groups by an etherification process using 1,2-epoxypropanol. Tablets for drug-controlled release were prepared by direct compression and their release properties assessed by an in vitro dissolution test (USP XXIII no 2). The polymer swelling was characterized by measuring gravimetrically the water uptake ability of polymer tablets. SA hydrophilic matrix tablets present sequentially a burst effect, typical of hydrophilic matrices, and a near constant release, typical of reservoir systems. After the burst effect, surface pores disappear progressively by molecular association of amylose chains; this allows the creation of a polymer layer acting as a diffusion barrier and explains the peculiar behaviour of SA polymers. Several formulation parameters such as compression force, drug loading, tablet weight and insoluble diluent concentration were investigated. On the other hand, tablet thickness, scanning electron microscope analysis and mercury intrusion porosimetry showed that the high crushing strength values observed for SA tablets were due to an unusual melting process occurring during tabletting although the tablet external layer went only through densification, deformation and partial melting. In contrast, HPMC tablets did not show any traces of a melting process

  16. LIBS analysis of artificial calcified tissues matrices.

    Science.gov (United States)

    Kasem, M A; Gonzalez, J J; Russo, R E; Harith, M A

    2013-04-15

    In most laser-based analytical methods, the reproducibility of quantitative measurements strongly depends on maintaining uniform and stable experimental conditions. For LIBS analysis this means that for accurate estimation of elemental concentration, using the calibration curves obtained from reference samples, the plasma parameters have to be kept as constant as possible. In addition, calcified tissues such as bone are normally less "tough" in their texture than many samples, especially metals. Thus, the ablation process could change the sample morphological features rapidly, and result in poor reproducibility statistics. In the present work, three artificial reference sample sets have been fabricated. These samples represent three different calcium based matrices, CaCO3 matrix, bone ash matrix and Ca hydroxyapatite matrix. A comparative study of UV (266 nm) and IR (1064 nm) LIBS for these three sets of samples has been performed under similar experimental conditions for the two systems (laser energy, spot size, repetition rate, irradiance, etc.) to examine the wavelength effect. The analytical results demonstrated that UV-LIBS has improved reproducibility, precision, stable plasma conditions, better linear fitting, and the reduction of matrix effects. Bone ash could be used as a suitable standard reference material for calcified tissue calibration using LIBS with a 266 nm excitation wavelength. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Neutrino mass matrices with vanishing determinant

    International Nuclear Information System (INIS)

    Chauhan, Bhag C.; Pulido, Joao; Picariello, Marco

    2006-01-01

    We investigate the prospects for neutrinoless double beta decay, texture zeros. and equalities between neutrino mass matrix elements in scenarios with vanishing determinant mass matrices for vanishing and finite θ 13 mixing angles in normal and inverse mass hierarchies. For normal hierarchy and both zero and finite θ 13 it is found that neutrinoless double beta decay cannot be observed by any of the present or next generation experiments, while for inverse hierarchy it is, on the contrary, accessible to experiments. Regarding texture zeros and equalities between mass matrix elements, we find that in both normal and inverse hierarchies with θ 13 =0 no texture zeros nor any such equalities can exist apart from the obvious ones. For θ 13 ≠0 some texture zeros become possible. In normal hierarchy two texture zeros occur if 8.1x10 -2 ≤sinθ 13 ≤9.1x10 -2 while in inverse hierarchy three are possible, one with sinθ 13 ≥7x10 -3 and two others with sinθ 13 ≥0.18. All equalities between mass matrix elements are impossible with θ 13 ≠0

  18. Calculating scattering matrices by wave function matching

    International Nuclear Information System (INIS)

    Zwierzycki, M.; Khomyakov, P.A.; Starikov, A.A.; Talanana, M.; Xu, P.X.; Karpan, V.M.; Marushchenko, I.; Brocks, G.; Kelly, P.J.; Xia, K.; Turek, I.; Bauer, G.E.W.

    2008-01-01

    The conductance of nanoscale structures can be conveniently related to their scattering properties expressed in terms of transmission and reflection coefficients. Wave function matching (WFM) is a transparent technique for calculating transmission and reflection matrices for any Hamiltonian that can be represented in tight-binding form. A first-principles Kohn-Sham Hamiltonian represented on a localized orbital basis or on a real space grid has such a form. WFM is based upon direct matching of the scattering-region wave function to the Bloch modes of ideal leads used to probe the scattering region. The purpose of this paper is to give a pedagogical introduction to WFM and present some illustrative examples of its use in practice. We briefly discuss WFM for calculating the conductance of atomic wires, using a real space grid implementation. A tight-binding muffin-tin orbital implementation very suitable for studying spin-dependent transport in layered magnetic materials is illustrated by looking at spin-dependent transmission through ideal and disordered interfaces. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Probing the Topology of Density Matrices

    Directory of Open Access Journals (Sweden)

    Charles-Edouard Bardyn

    2018-02-01

    Full Text Available The mixedness of a quantum state is usually seen as an adversary to topological quantization of observables. For example, exact quantization of the charge transported in a so-called Thouless adiabatic pump is lifted at any finite temperature in symmetry-protected topological insulators. Here, we show that certain directly observable many-body correlators preserve the integrity of topological invariants for mixed Gaussian quantum states in one dimension. Our approach relies on the expectation value of the many-body momentum-translation operator and leads to a physical observable—the “ensemble geometric phase” (EGP—which represents a bona fide geometric phase for mixed quantum states, in the thermodynamic limit. In cyclic protocols, the EGP provides a topologically quantized observable that detects encircled spectral singularities (“purity-gap” closing points of density matrices. While we identify the many-body nature of the EGP as a key ingredient, we propose a conceptually simple, interferometric setup to directly measure the latter in experiments with mesoscopic ensembles of ultracold atoms.

  20. Visualizing complex (hydrological) systems with correlation matrices

    Science.gov (United States)

    Haas, J. C.

    2016-12-01

    When trying to understand or visualize the connections of different aspects of a complex system, this often requires deeper understanding to start with, or - in the case of geo data - complicated GIS software. To our knowledge, correlation matrices have rarely been used in hydrology (e.g. Stoll et al., 2011; van Loon and Laaha, 2015), yet they do provide an interesting option for data visualization and analysis. We present a simple, python based way - using a river catchment as an example - to visualize correlations and similarities in an easy and colorful way. We apply existing and easy to use python packages from various disciplines not necessarily linked to the Earth sciences and can thus quickly show how different aquifers work or react, and identify outliers, enabling this system to also be used for quality control of large datasets. Going beyond earlier work, we add a temporal and spatial element, enabling us to visualize how a system reacts to local phenomena such as for example a river, or changes over time, by visualizing the passing of time in an animated movie. References: van Loon, A.F., Laaha, G.: Hydrological drought severity explained by climate and catchment characteristics, Journal of Hydrology 526, 3-14, 2015, Drought processes, modeling, and mitigation Stoll, S., Hendricks Franssen, H. J., Barthel, R., Kinzelbach, W.: What can we learn from long-term groundwater data to improve climate change impact studies?, Hydrology and Earth System Sciences 15(12), 3861-3875, 2011

  1. Decellularized matrices for cardiovascular tissue engineering.

    Science.gov (United States)

    Moroni, Francesco; Mirabella, Teodelinda

    2014-01-01

    Cardiovascular disease (CVD) is one of the leading causes of death in the Western world. The replacement of damaged vessels and valves has been practiced since the 1950's. Synthetic grafts, usually made of bio-inert materials, are long-lasting and mechanically relevant, but fail when it comes to "biointegration". Decellularized matrices, instead, can be considered biological grafts capable of stimulating in vivo migration and proliferation of endothelial cells (ECs), recruitment and differentiation of mural cells, finally, culminating in the formation of a biointegrated tissue. Decellularization protocols employ osmotic shock, ionic and non-ionic detergents, proteolitic digestions and DNase/RNase treatments; most of them effectively eliminate the cellular component, but show limitations in preserving the native structure of the extracellular matrix (ECM). In this review, we examine the current state of the art relative to decellularization techniques and biological performance of decellularized heart, valves and big vessels. Furthermore, we focus on the relevance of ECM components, native and resulting from decellularization, in mediating in vivo host response and determining repair and regeneration, as opposed to graft corruption.

  2. On some Toeplitz matrices and their inversions

    Directory of Open Access Journals (Sweden)

    S. Dutta

    2014-10-01

    Full Text Available In this article, using the difference operator B(a[m], we introduce a lower triangular Toeplitz matrix T which includes several difference matrices such as Δ(1,Δ(m,B(r,s,B(r,s,t, and B(r̃,s̃,t̃,ũ in different special cases. For any x ∈ w and m∈N0={0,1,2,…}, the difference operator B(a[m] is defined by (B(a[m]xk=ak(0xk+ak-1(1xk-1+ak-2(2xk-2+⋯+ak-m(mxk-m,(k∈N0 where a[m] = {a(0, a(1, …, a(m} and a(i = (ak(i for 0 ⩽ i ⩽ m are convergent sequences of real numbers. We use the convention that any term with negative subscript is equal to zero. The main results of this article relate to the determination and applications of the inverse of the Toeplitz matrix T.

  3. Evolution of organic matter in Orgueil, Murchison and Renazzo during parent body aqueous alteration: In situ investigations

    Science.gov (United States)

    Le Guillou, Corentin; Bernard, Sylvain; Brearley, Adrian J.; Remusat, Laurent

    2014-04-01

    Chondrites accreted the oldest solid materials in the solar system including dust processed in the protoplanetary disk and diverse organic compounds. After accretion, asteroidal alteration may have impacted organic particles in various ways. To constrain these processes, we conducted a comprehensive study of organics disseminated within the matrices of the three carbonaceous chondrite falls, Renazzo (CR2), Murchison (CM2) and Orgueil (CI). By combining synchrotron-based STXM and TEM analyses on FIB sections of samples previously characterized by NanoSIMS, we investigated the influence of aqueous alteration on the morphology, isotopic signature, molecular structure, spatial distribution, and mineralogical environment of the organic matter within the matrices. Two different populations of materials are distinguishable: sub-micrometric individual grains, likely dominated by insoluble compounds and diffuse organic matter, finely interspersed within phyllosilicates and/or (amorphous) nanocarbonates at the nanometer scale. We suggest that this latter component, which is depleted in aromatics and enriched in carboxylic functional groups, may be dominated by soluble compounds. Organic matter in Renazzo (CR) mainly consists of chemically-homogeneous individual grains surrounded by amorphous and nanocrystalline phyllosilicates. Evidence of connectivity between organic grains and fractures indicates that redistribution has occurred: some areas containing diffuse organic matter can be observed. This diffuse organic component is more abundant in Murchison (CM) and Orgueil (CI). This is interpreted as resulting from fluid transport at the micrometer scale and encapsulation within recrystallized alteration phases. In contrast to Renazzo, organic grains in Murchison and Orgueil display strong chemical heterogeneities, likely related to chemical evolution during aqueous alteration. The observations suggest that the altering fluid was a brine with elevated concentrations of both

  4. Effects of soluble organic complexants and their degradation products on the removal of selected radionuclides from high-level waste. Part II: Distributions of Sr, Cs, Tc, and Am onto 32 absorbers from four variations of Hanford tank 101-SY simulant solution

    International Nuclear Information System (INIS)

    Marsh, S.F.; Svitra, Z.V.; Bowen, S.M.

    1995-04-01

    Many of the radioactive waste storage tanks at U.S. Department of Energy facilities contain organic compounds that have been degraded by radiolysis and chemical reactions during decades of storage. In this second part of our three-part investigation of the effects of soluble organic complexants and their degradation products, we measured the sorption of strontium, cesium, technetium, and americium onto 32 absorbers that offer high sorption of these elements in the absence of organic complexants. The four solutions tested were (1) a simulant for a 3:1 dilution of Hanford Tank 101-SY contents that initially contained ethylenediaminetetraacetic acid (EDTA), (2) this simulant after gamma-irradiation to 34 Mrads, (3) the unirradiated simulant after treatment with a hydrothermal organic-destruction process, and (4) the irradiated simulant after hydrothermal processing. For each of 512 element/absorber/solution combinations, we measured distribution coefficients (Kds) twice for each period for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. On the basis of our 3,072 measured Kd values, the sorption of strontium and americium is significantly decreased by the organic components of the simulant solutions, whereas the sorption of cesium and technetium appears unaffected by the organic components of the simulant solutions

  5. Mise en évidence de Provinces géochimiques dans les schistes bitumeux du Toarcien de l'est du bassin de Paris Geocheminical Provinces Revealed in Toarcien Oil Shales in the Eastern Paris Basin. Analysis of the Soluble Organic Fraction

    Directory of Open Access Journals (Sweden)

    Huc A. Y.

    2006-11-01

    Full Text Available L'étude de la matière organique soluble dans le chloroforme des schistes du Toarcien de la partie orientale du bassin de Paris met en évidence l'existence d'une province géochimique nord et d'une province géochimique sud dont la frontière commune se trouve dans la région de Fécocourt. La province septentrionale se caractérise par une influence du domaine continental (massif des Ardennes au niveau de l'apport organique. Alors que la province méridionale se révèle exempt d'apport terrestre. Ces résultats sont en accord avec les indications sédimentologiques fournies par la littérature et apportent une dimension géochimique à la paléogéographie de ce bassin. An anaalysis of soluble organic motter in the chloroform from Toarcian shales from the eastern part of the Paris Basin reveals the existence of a northern geochemical province and a southern geochemical province whose commun boundary lies in the Fecocourt region. The northern province is characterized by the influence of the continental domain (Ardennes range with regard to organic influx, whereas no terrestrial influx is found in the southern province. These findings agree with the sedimentological indications supplied by the literature and add a geochemical dimension to the paleogeography of this basin.

  6. Information geometry of density matrices and state estimation

    International Nuclear Information System (INIS)

    Brody, Dorje C

    2011-01-01

    Given a pure state vector |x) and a density matrix ρ-hat, the function p(x|ρ-hat)= defines a probability density on the space of pure states parameterised by density matrices. The associated Fisher-Rao information measure is used to define a unitary invariant Riemannian metric on the space of density matrices. An alternative derivation of the metric, based on square-root density matrices and trace norms, is provided. This is applied to the problem of quantum-state estimation. In the simplest case of unitary parameter estimation, new higher-order corrections to the uncertainty relations, applicable to general mixed states, are derived. (fast track communication)

  7. Chain of matrices, loop equations and topological recursion

    CERN Document Server

    Orantin, Nicolas

    2009-01-01

    Random matrices are used in fields as different as the study of multi-orthogonal polynomials or the enumeration of discrete surfaces. Both of them are based on the study of a matrix integral. However, this term can be confusing since the definition of a matrix integral in these two applications is not the same. These two definitions, perturbative and non-perturbative, are discussed in this chapter as well as their relation. The so-called loop equations satisfied by integrals over random matrices coupled in chain is discussed as well as their recursive solution in the perturbative case when the matrices are Hermitean.

  8. Aqueous solubility, dispersibility and toxicity of biodiesels

    International Nuclear Information System (INIS)

    Hollebone, B.P.; Fieldhouse, B.; Lumley, T.C.; Landriault, M.; Doe, K.; Jackman, P.

    2007-01-01

    fuel. It was determined that chemical composition of the water-soluble fractions of blends of biodiesels and petrodiesels can be modeled by a linear combination of the water-soluble fraction chemistries of the neat petro- and biodiesels. Petroleum diesels appear to be 5 to 10 times more acutely toxic to aquatic organisms than pure biodiesels. Biodiesels were found to disperse very completely in high energy conditions. 17 refs., 5 tabs., 3 figs

  9. Modular Extracellular Matrices: Solutions for the Puzzle

    Science.gov (United States)

    Serban, Monica A.; Prestwich, Glenn D.

    2008-01-01

    The common technique of growing cells in two-dimensions (2-D) is gradually being replaced by culturing cells on matrices with more appropriate composition and stiffness, or by encapsulation of cells in three-dimensions (3-D). The universal acceptance of the new 3-D paradigm has been constrained by the absence of a commercially available, biocompatible material that offers ease of use, experimental flexibility, and a seamless transition from in vitro to in vivo applications. The challenge – the puzzle that needs a solution – is to replicate the complexity of the native extracellular matrix (ECM) environment with the minimum number of components necessary to allow cells to rebuild and replicate a given tissue. For use in drug discovery, toxicology, cell banking, and ultimately in reparative medicine, the ideal matrix would therefore need to be highly reproducible, manufacturable, approvable, and affordable. Herein we describe the development of a set of modular components that can be assembled into biomimetic materials that meet these requirements. These semi-synthetic ECMs, or sECMs, are based on hyaluronan derivatives that form covalently crosslinked, biodegradable hydrogels suitable for 3-D culture of primary and stem cells in vitro, and for tissue formation in vivo. The sECMs can be engineered to provide appropriate biological cues needed to recapitulate the complexity of a given ECM environment. Specific applications for different sECM compositions include stem cell expansion with control of differentiation, scar-free wound healing, growth factor delivery, cell delivery for osteochondral defect and liver repair, and development of vascularized tumor xenografts for personalized chemotherapy. PMID:18442709

  10. Comparison of eigensolvers for symmetric band matrices.

    Science.gov (United States)

    Moldaschl, Michael; Gansterer, Wilfried N

    2014-09-15

    We compare different algorithms for computing eigenvalues and eigenvectors of a symmetric band matrix across a wide range of synthetic test problems. Of particular interest is a comparison of state-of-the-art tridiagonalization-based methods as implemented in Lapack or Plasma on the one hand, and the block divide-and-conquer (BD&C) algorithm as well as the block twisted factorization (BTF) method on the other hand. The BD&C algorithm does not require tridiagonalization of the original band matrix at all, and the current version of the BTF method tridiagonalizes the original band matrix only for computing the eigenvalues. Avoiding the tridiagonalization process sidesteps the cost of backtransformation of the eigenvectors. Beyond that, we discovered another disadvantage of the backtransformation process for band matrices: In several scenarios, a lot of gradual underflow is observed in the (optional) accumulation of the transformation matrix and in the (obligatory) backtransformation step. According to the IEEE 754 standard for floating-point arithmetic, this implies many operations with subnormal (denormalized) numbers, which causes severe slowdowns compared to the other algorithms without backtransformation of the eigenvectors. We illustrate that in these cases the performance of existing methods from Lapack and Plasma reaches a competitive level only if subnormal numbers are disabled (and thus the IEEE standard is violated). Overall, our performance studies illustrate that if the problem size is large enough relative to the bandwidth, BD&C tends to achieve the highest performance of all methods if the spectrum to be computed is clustered. For test problems with well separated eigenvalues, the BTF method tends to become the fastest algorithm with growing problem size.

  11. MATXTST, Basic Operations for Covariance Matrices

    International Nuclear Information System (INIS)

    Geraldo, Luiz P.; Smith, Donald

    1989-01-01

    1 - Description of program or function: MATXTST and MATXTST1 perform the following operations for a covariance matrix: - test for singularity; - test for positive definiteness; - compute the inverse if the matrix is non-singular; - compute the determinant; - determine the number of positive, negative, and zero eigenvalues; - examine all possible 3 X 3 cross correlations within a sub-matrix corresponding to a leading principal minor which is non-positive definite. While the two programs utilize the same input, the calculational procedures employed are somewhat different and their functions are complementary. The available input options include: i) the full covariance matrix, ii) the basic variables plus the relative covariance matrix, or iii) uncertainties in the basic variables plus the correlation matrix. 2 - Method of solution: MATXTST employs LINPACK subroutines SPOFA and SPODI to test for positive definiteness and to perform further optional calculations. Subroutine SPOFA factors a symmetric matrix M using the Cholesky algorithm to determine the elements of a matrix R which satisfies the relation M=R'R, where R' is the transposed matrix of R. Each leading principal minor of M is tested until the first one is found which is not positive definite. MATXTST1 uses LINPACK subroutines SSICO, SSIFA, and SSIDI to estimate whether the matrix is near to singularity or not (SSICO), and to perform the matrix diagonalization process (SSIFA). The algorithm used in SSIFA is generalization of the Method of Lagrange Reduction. SSIDI is used to compute the determinant and inertia of the matrix. 3 - Restrictions on the complexity of the problem: Matrices of sizes up to 50 X 50 elements can be treated by present versions of the programs

  12. On nitrogen solubility in water

    International Nuclear Information System (INIS)

    Kalajda, Yu.A.; Katkov, Yu.D.; Kuznetsov, V.A.; Lastovtsev, A.Yu.; Lastochkin, A.P.; Susoev, V.S.

    1980-01-01

    Presented are the results of experimental investigations on nitrogen solubility in water under 0-15 MPa pressure, at the temperature of 100-340 deg C and nitrogen concentration of 0-5000 n.ml. N 2 /kg H 2 O. Empiric equations are derived and a diagram of nitrogen solubility in water is developed on the basis of the experimental data, as well as critically evaluated published data. The investigation results can be used in analyzing water-gas regime of a primary heat carrier in stream-generating plants with water-water reactors

  13. Preliminary considerations concerning actinide solubilities

    International Nuclear Information System (INIS)

    Newton, T.W.; Bayhurst, B.P.; Daniels, W.R.; Erdal, B.R.; Ogard, A.E.

    1980-01-01

    Work at the Los Alamos Scientific Laboratory on the fundamental solution chemistry of the actinides has thus far been confined to preliminary considerations of the problems involved in developing an understanding of the precipitation and dissolution behavior of actinide compounds under environmental conditions. Attempts have been made to calculate solubility as a function of Eh and pH using the appropriate thermodynamic data; results have been presented in terms of contour maps showing lines of constant solubility as a function of Eh and pH. Possible methods of control of the redox potential of rock-groundwater systems by the use of Eh buffers (redox couples) is presented

  14. Thorium oxalate solubility and morphology

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.; Hall, R.

    1981-10-01

    Thorium was used as a stand-in for studying the solubility and precipitation of neptunium and plutonium oxalates. Thorium oxalate solubility was determined over a range of 0.001 to 10.0 in the concentration parameter [H 2 C 2 O 4 ]/[HNO 3 ] 2 . Morphology of thorium oxide made from the oxalate precipitates was characterized by scanning electron microscopy. The different morphologies found for oxalate-lean and oxalate-rich precipitations were in agreement with predictions based on precipitation theory

  15. Solubility database for TILA-99

    Energy Technology Data Exchange (ETDEWEB)

    Vuorinen, U.; Carlsson, T. [VTT Chemical Technology, Espoo (Finland); Kulmala, S.; Hakanen, M. [Helsinki Univ. (Finland). Lab. of Radiochemistry; Ahonen, L. [Geological Survey of Finland, Espoo (Finland)

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water ({approx}70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites

  16. Solubility database for TILA-99

    International Nuclear Information System (INIS)

    Vuorinen, U.; Carlsson, T.; Kulmala, S.; Hakanen, M.

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water (∼70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites. The

  17. Joint Estimation of Multiple Precision Matrices with Common Structures.

    Science.gov (United States)

    Lee, Wonyul; Liu, Yufeng

    Estimation of inverse covariance matrices, known as precision matrices, is important in various areas of statistical analysis. In this article, we consider estimation of multiple precision matrices sharing some common structures. In this setting, estimating each precision matrix separately can be suboptimal as it ignores potential common structures. This article proposes a new approach to parameterize each precision matrix as a sum of common and unique components and estimate multiple precision matrices in a constrained l 1 minimization framework. We establish both estimation and selection consistency of the proposed estimator in the high dimensional setting. The proposed estimator achieves a faster convergence rate for the common structure in certain cases. Our numerical examples demonstrate that our new estimator can perform better than several existing methods in terms of the entropy loss and Frobenius loss. An application to a glioblastoma cancer data set reveals some interesting gene networks across multiple cancer subtypes.

  18. Systems of Differential Equations with Skew-Symmetric, Orthogonal Matrices

    Science.gov (United States)

    Glaister, P.

    2008-01-01

    The solution of a system of linear, inhomogeneous differential equations is discussed. The particular class considered is where the coefficient matrix is skew-symmetric and orthogonal, and where the forcing terms are sinusoidal. More general matrices are also considered.

  19. Finiteness properties of congruence classes of infinite matrices

    NARCIS (Netherlands)

    Eggermont, R.H.

    2014-01-01

    We look at spaces of infinite-by-infinite matrices, and consider closed subsets that are stable under simultaneous row and column operations. We prove that up to symmetry, any of these closed subsets is defined by finitely many equations.

  20. Flexible Bayesian Dynamic Modeling of Covariance and Correlation Matrices

    KAUST Repository

    Lan, Shiwei; Holbrook, Andrew; Fortin, Norbert J.; Ombao, Hernando; Shahbaba, Babak

    2017-01-01

    Modeling covariance (and correlation) matrices is a challenging problem due to the large dimensionality and positive-definiteness constraint. In this paper, we propose a novel Bayesian framework based on decomposing the covariance matrix

  1. Impact of earthworms on trace element solubility in contaminated mine soils amended with green waste compost

    Energy Technology Data Exchange (ETDEWEB)

    Sizmur, Tom, E-mail: t.p.sizmur@reading.ac.uk [Soil Research Centre, Dept. Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, RG6 6DW (United Kingdom); Palumbo-Roe, Barbara [British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham, NG12 5GG (United Kingdom); Hodson, Mark E. [Soil Research Centre, Dept. Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, RG6 6DW (United Kingdom)

    2011-07-15

    The common practice of remediating metal contaminated mine soils with compost can reduce metal mobility and promote revegetation, but the effect of introduced or colonising earthworms on metal solubility is largely unknown. We amended soils from an As/Cu (1150 mgAs kg{sup -1} and 362 mgCu kg{sup -1}) and Pb/Zn mine (4550 mgPb kg{sup -1} and 908 mgZn kg{sup -1}) with 0, 5, 10, 15 and 20% compost and then introduced Lumbricus terrestris. Porewater was sampled and soil extracted with water to determine trace element solubility, pH and soluble organic carbon. Compost reduced Cu, Pb and Zn, but increased As solubility. Earthworms decreased water soluble Cu and As but increased Pb and Zn in porewater. The effect of the earthworms decreased with increasing compost amendment. The impact of the compost and the earthworms on metal solubility is explained by their effect on pH and soluble organic carbon and the environmental chemistry of each element. - Graphical abstract: Display Omitted Highlights: > Compost reduced the mobility of Cu, Pb and Zn. > Compost increased the mobility of As. > Earthworms decreased water soluble As and Cu but increased Pb and Zn in porewater. > These effects are explained by the impact of the earthworms and compost on pH and DOC. - The effect of earthworms on metal solubility was due to changes in dissolved organic carbon and pH but was reduced with increasing compost amendments.

  2. Impact of earthworms on trace element solubility in contaminated mine soils amended with green waste compost

    International Nuclear Information System (INIS)

    Sizmur, Tom; Palumbo-Roe, Barbara; Hodson, Mark E.

    2011-01-01

    The common practice of remediating metal contaminated mine soils with compost can reduce metal mobility and promote revegetation, but the effect of introduced or colonising earthworms on metal solubility is largely unknown. We amended soils from an As/Cu (1150 mgAs kg -1 and 362 mgCu kg -1 ) and Pb/Zn mine (4550 mgPb kg -1 and 908 mgZn kg -1 ) with 0, 5, 10, 15 and 20% compost and then introduced Lumbricus terrestris. Porewater was sampled and soil extracted with water to determine trace element solubility, pH and soluble organic carbon. Compost reduced Cu, Pb and Zn, but increased As solubility. Earthworms decreased water soluble Cu and As but increased Pb and Zn in porewater. The effect of the earthworms decreased with increasing compost amendment. The impact of the compost and the earthworms on metal solubility is explained by their effect on pH and soluble organic carbon and the environmental chemistry of each element. - Graphical abstract: Display Omitted Highlights: → Compost reduced the mobility of Cu, Pb and Zn. → Compost increased the mobility of As. → Earthworms decreased water soluble As and Cu but increased Pb and Zn in porewater. → These effects are explained by the impact of the earthworms and compost on pH and DOC. - The effect of earthworms on metal solubility was due to changes in dissolved organic carbon and pH but was reduced with increasing compost amendments.

  3. Isotope dilution liquid chromatography - mass spectrometry methods for fat- and water-soluble vitamins in nutritional formulations.

    Science.gov (United States)

    Phinney, Karen W; Rimmer, Catherine A; Thomas, Jeanice Brown; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A

    2011-01-01

    Vitamins are essential to human health, and dietary supplements containing vitamins are widely used by individuals hoping to ensure they have adequate intake of these important nutrients. Measurement of vitamins in nutritional formulations is necessary to monitor regulatory compliance and in studies examining the nutrient intake of specific populations. Liquid chromatographic methods, primarily with UV absorbance detection, are well established for both fat- and water-soluble measurements, but they do have limitations for certain analytes and may suffer from a lack of specificity in complex matrices. Liquid chromatography-mass spectrometry (LC-MS) provides both sensitivity and specificity for the determination of vitamins in these matrices, and simultaneous analysis of multiple vitamins in a single analysis is often possible. In this work, LC-MS methods were developed for both fat- and water-soluble vitamins and applied to the measurement of these analytes in two NIST Standard Reference Materials. When possible, stable isotope labeled internal standards were employed for quantification.

  4. Procrustes Problems for General, Triangular, and Symmetric Toeplitz Matrices

    Directory of Open Access Journals (Sweden)

    Juan Yang

    2013-01-01

    Full Text Available The Toeplitz Procrustes problems are the least squares problems for the matrix equation AX=B over some Toeplitz matrix sets. In this paper the necessary and sufficient conditions are obtained about the existence and uniqueness for the solutions of the Toeplitz Procrustes problems when the unknown matrices are constrained to the general, the triangular, and the symmetric Toeplitz matrices, respectively. The algorithms are designed and the numerical examples show that these algorithms are feasible.

  5. An introduction to the theory of canonical matrices

    CERN Document Server

    Turnbull, H W

    2004-01-01

    Thorough and self-contained, this penetrating study of the theory of canonical matrices presents a detailed consideration of all the theory's principal features. Topics include elementary transformations and bilinear and quadratic forms; canonical reduction of equivalent matrices; subgroups of the group of equivalent transformations; and rational and classical canonical forms. The final chapters explore several methods of canonical reduction, including those of unitary and orthogonal transformations. 1952 edition. Index. Appendix. Historical notes. Bibliographies. 275 problems.

  6. Dynamical correlations for circular ensembles of random matrices

    International Nuclear Information System (INIS)

    Nagao, Taro; Forrester, Peter

    2003-01-01

    Circular Brownian motion models of random matrices were introduced by Dyson and describe the parametric eigenparameter correlations of unitary random matrices. For symmetric unitary, self-dual quaternion unitary and an analogue of antisymmetric Hermitian matrix initial conditions, Brownian dynamics toward the unitary symmetry is analyzed. The dynamical correlation functions of arbitrary number of Brownian particles at arbitrary number of times are shown to be written in the forms of quaternion determinants, similarly as in the case of Hermitian random matrix models

  7. Complementary Set Matrices Satisfying a Column Correlation Constraint

    OpenAIRE

    Wu, Di; Spasojevic, Predrag

    2006-01-01

    Motivated by the problem of reducing the peak to average power ratio (PAPR) of transmitted signals, we consider a design of complementary set matrices whose column sequences satisfy a correlation constraint. The design algorithm recursively builds a collection of $2^{t+1}$ mutually orthogonal (MO) complementary set matrices starting from a companion pair of sequences. We relate correlation properties of column sequences to that of the companion pair and illustrate how to select an appropriate...

  8. Open vessel microwave digestion of food matrices (T6)

    International Nuclear Information System (INIS)

    Rhodes, L.; LeBlanc, G.

    2002-01-01

    Full text: Advancements in the field of open vessel microwave digestion continue to provide solutions for industries requiring acid digestion of large sample sizes. Those interesting in digesting food matrices are particularly interested in working with large amounts of sample and then diluting small final volumes. This paper will show the advantages of instantaneous regent addition and post-digestion evaporation when performing an open vessel digestion and evaporation methods for various food matrices will be presented along with analyte recovery data. (author)

  9. Quantum Algorithms for Weighing Matrices and Quadratic Residues

    OpenAIRE

    van Dam, Wim

    2000-01-01

    In this article we investigate how we can employ the structure of combinatorial objects like Hadamard matrices and weighing matrices to device new quantum algorithms. We show how the properties of a weighing matrix can be used to construct a problem for which the quantum query complexity is ignificantly lower than the classical one. It is pointed out that this scheme captures both Bernstein & Vazirani's inner-product protocol, as well as Grover's search algorithm. In the second part of the ar...

  10. Asymptotic Distribution of Eigenvalues of Weakly Dilute Wishart Matrices

    Energy Technology Data Exchange (ETDEWEB)

    Khorunzhy, A. [Institute for Low Temperature Physics (Ukraine)], E-mail: khorunjy@ilt.kharkov.ua; Rodgers, G. J. [Brunel University, Uxbridge, Department of Mathematics and Statistics (United Kingdom)], E-mail: g.j.rodgers@brunel.ac.uk

    2000-03-15

    We study the eigenvalue distribution of large random matrices that are randomly diluted. We consider two random matrix ensembles that in the pure (nondilute) case have a limiting eigenvalue distribution with a singular component at the origin. These include the Wishart random matrix ensemble and Gaussian random matrices with correlated entries. Our results show that the singularity in the eigenvalue distribution is rather unstable under dilution and that even weak dilution destroys it.

  11. Inference for High-dimensional Differential Correlation Matrices.

    Science.gov (United States)

    Cai, T Tony; Zhang, Anru

    2016-01-01

    Motivated by differential co-expression analysis in genomics, we consider in this paper estimation and testing of high-dimensional differential correlation matrices. An adaptive thresholding procedure is introduced and theoretical guarantees are given. Minimax rate of convergence is established and the proposed estimator is shown to be adaptively rate-optimal over collections of paired correlation matrices with approximately sparse differences. Simulation results show that the procedure significantly outperforms two other natural methods that are based on separate estimation of the individual correlation matrices. The procedure is also illustrated through an analysis of a breast cancer dataset, which provides evidence at the gene co-expression level that several genes, of which a subset has been previously verified, are associated with the breast cancer. Hypothesis testing on the differential correlation matrices is also considered. A test, which is particularly well suited for testing against sparse alternatives, is introduced. In addition, other related problems, including estimation of a single sparse correlation matrix, estimation of the differential covariance matrices, and estimation of the differential cross-correlation matrices, are also discussed.

  12. Solubility limits on radionuclide dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  13. Solubility of Nd in brine

    International Nuclear Information System (INIS)

    Khalili, F.I.; Symeopoulos, V.; Chen, J.F.; Choppin, G.R.

    1994-01-01

    The solubility of Nd(III) has been measured at 23±3 C in a synthetic brine at pcH 6.4, 8.4, 10.4 and 12.4. The brine consisted predominantly of (Na+K)Cl and MgCl 2 with an ionic strength of 7.8 M (9.4 m) a solid compound of Nd(III) at each pcH was assigned from X-ray diffraction patterns. The log values of the experimental solubilities decrease fomr -3 at pcH 6.4 to -5.8 at pcH 8.4; at pcH 10.4 and 12.4 the solubility was below the detection limit of -7.5. The experimental solubility does not follow closely the variation with pcH estimated from modeling of the species in solution in equilibrium with the Nd solid using S.I.T. (orig.)

  14. Estimated correlation matrices and portfolio optimization

    Science.gov (United States)

    Pafka, Szilárd; Kondor, Imre

    2004-11-01

    Correlations of returns on various assets play a central role in financial theory and also in many practical applications. From a theoretical point of view, the main interest lies in the proper description of the structure and dynamics of correlations, whereas for the practitioner the emphasis is on the ability of the models to provide adequate inputs for the numerous portfolio and risk management procedures used in the financial industry. The theory of portfolios, initiated by Markowitz, has suffered from the “curse of dimensions” from the very outset. Over the past decades a large number of different techniques have been developed to tackle this problem and reduce the effective dimension of large bank portfolios, but the efficiency and reliability of these procedures are extremely hard to assess or compare. In this paper, we propose a model (simulation)-based approach which can be used for the systematical testing of all these dimensional reduction techniques. To illustrate the usefulness of our framework, we develop several toy models that display some of the main characteristic features of empirical correlations and generate artificial time series from them. Then, we regard these time series as empirical data and reconstruct the corresponding correlation matrices which will inevitably contain a certain amount of noise, due to the finiteness of the time series. Next, we apply several correlation matrix estimators and dimension reduction techniques introduced in the literature and/or applied in practice. As in our artificial world the only source of error is the finite length of the time series and, in addition, the “true” model, hence also the “true” correlation matrix, are precisely known, therefore in sharp contrast with empirical studies, we can precisely compare the performance of the various noise reduction techniques. One of our recurrent observations is that the recently introduced filtering technique based on random matrix theory performs

  15. Influencing the solubility of oxalates for the preparation of ceramic powders from mixed precipitates

    International Nuclear Information System (INIS)

    Krueger, C.; Fischer, S.; Fischer, St.; Chebani, M.Kh.

    1991-01-01

    Based on investigations of the solubility of oxalate with 140 Ba, 64 Cu and 59 Fe, techniques for quantitative oxalate coprecipitation were developed. Addition of organic solvents lowers the solubility and leads to a smaller particle size of products. (orig.) [de

  16. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol-Water Mixtures

    NARCIS (Netherlands)

    Bowden, Nathan A.; Sanders, Johan P.M.; Bruins, Marieke E.

    2018-01-01

    The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization. We reviewed the available data on the solubility of α-amino acids in water, water-ethanol mixtures, and ethanol at 298.15 K and 0.1 MPa. The solubility of l-alanine, l-proline,

  17. Electrospun composite matrices of poly(ε-caprolactone)-montmorillonite made using tenside free Pickering emulsions.

    Science.gov (United States)

    Samanta, Archana; Takkar, Sonam; Kulshreshtha, Ritu; Nandan, Bhanu; Srivastava, Rajiv K

    2016-12-01

    The production of composite electrospun matrices of poly(ε-caprolactone) (PCL) using an emulsifier-free emulsion, made with minimal organic solvent, as precursor is reported. Pickering emulsions of PCL were prepared using modified montmorillonite (MMT) clay as the stabilizer. Hydrophobic tallow group of the modified MMT clay resulted in analogous interaction of clay with oil and aqueous phase and its adsorption at the interface to provide stability to the resultant emulsion. Composite fibrous matrices of PCL and MMT were produced using electrospinning under controlled conditions. The fiber fineness was found to alter with PCL concentration and volume fraction of the aqueous and oil phases. A higher tensile strength and modulus was obtained with inclusion of MMT in PCL electrospun matrix in comparison to a matrix made using neat PCL. The presence of clay in the fibrous matrix did not change the cell proliferation efficiency in comparison to neat PCL matrix. Composite fibrous matrices of PCL/MMT bearing enhanced tensile properties may find applications in areas other than tissue engineering for example food packaging and filtration. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Flavonoids as matrices for MALDI-TOF mass spectrometric analysis of transition metal complexes

    Science.gov (United States)

    Petkovic, Marijana; Petrovic, Biljana; Savic, Jasmina; Bugarcic, Zivadin D.; Dimitric-Markovic, Jasmina; Momic, Tatjana; Vasic, Vesna

    2010-02-01

    Matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a suitable method for the analysis of inorganic and organic compounds and biomolecules. This makes MALDI-TOF MS convenient for monitoring the interaction of metallo-drugs with biomolecules. Results presented in this manuscript demonstrate that flavonoids such as apigenin, kaempferol and luteolin are suitable for MALDI-TOF MS analysis of Pt(II), Pd(II), Pt(IV) and Ru(III) complexes, giving different signal-to-noise ratios of the analyte peak. The MALDI-TOF mass spectra of inorganic complexes acquired with these flavonoid matrices are easy to interpret and have some advantages over the application of other commonly used matrices: a low number of matrix peaks are detectable and the coordinative metal-ligand bond is, in most cases, preserved. On the other hand, flavonoids do not act as typical matrices, as their excess is not required for the acquisition of MALDI-TOF mass spectra of inorganic complexes.

  19. Composites reinforced via mechanical interlocking of surface-roughened microplatelets within ductile and brittle matrices.

    Science.gov (United States)

    Libanori, R; Carnelli, D; Rothfuchs, N; Binelli, M R; Zanini, M; Nicoleau, L; Feichtenschlager, B; Albrecht, G; Studart, A R

    2016-04-12

    Load-bearing reinforcing elements in a continuous matrix allow for improved mechanical properties and can reduce the weight of structural composites. As the mechanical performance of composite systems are heavily affected by the interfacial properties, tailoring the interactions between matrices and reinforcing elements is a crucial problem. Recently, several studies using bio-inspired model systems suggested that interfacial mechanical interlocking is an efficient mechanism for energy dissipation in platelet-reinforced composites. While cheap and effective solutions are available at the macroscale, the modification of surface topography in micron-sized reinforcing elements still represents a challenging task. Here, we report a simple method to create nanoasperities with tailored sizes and densities on the surface of alumina platelets and investigate their micromechanical effect on the energy dissipation mechanisms of nacre-like materials. Composites reinforced with roughened platelets exhibit improved mechanical properties for both organic ductile epoxy and inorganic brittle cement matrices. Mechanical interlocking increases the modulus of toughness (area under the stress-strain curve) by 110% and 56% in epoxy and cement matrices, respectively, as compared to those reinforced with flat platelets. This interlocking mechanism can potentially lead to a significant reduction in the weight of mechanical components while retaining the structural performance required in the application field.

  20. The influence of inorganic matrices on the decomposition of Eucalyptus litter

    International Nuclear Information System (INIS)

    Skene, T.M.; Oades, J.M.; Clarke, P.J.; Skjemstad, J.O.; Oades, J.M.; Skjemstad, J.O.

    1997-01-01

    The decomposition of Eucalyptus litter (EL) in the presence and absence of inorganic matrices [sad (S), sand+kaolin (S+K), loamy sand (LS)] with and without added N (urea) was followed over 48 weeks using chemical and spectroscopic means. At the end of the incubation, the residual organic matter in different density and particle size fractions was examined. Urea addition inhibited the mineralisation of C from the litter in all treatments except EL+S+N, whereas the inorganic matrices had little influence on mineralisation. Solid state 13 C CP/MAS NMR spectra of the whole samples suggested there were no differences in the treatments, despite significant differences in the amount of C mineralized. The NMR spectra of the whole samples suggest that a reaction between aromatic-C and urea occurred during thr first week of the incubation which may have rendered the N unavailable to microorganisms. The results were quite different from a similar study on the decomposition of straw. these differences suggest that, for high quality substrates, physical protection by inorganic matrices is the limiting factor to decomposition, whereas for low quality substrates, chemical protection is the limiting factor. 13 refs., 2 tabs., 6 figs

  1. THE DYNAMICS OF THE MATRICS STRUCTURE

    Directory of Open Access Journals (Sweden)

    Dumitru CONSTANTINESCU

    2007-01-01

    Full Text Available The relationships organization-suppliers-customers have recently known major changes in the structure of services and have made the organization develop its managerial and professional competencies in order to do projects. The qualified organization is the most trust-worthy in the process of doing a project. The participation of an organization in doing projects depends on a multitude of factors. Out of these factors, the structural organization comes forth, as it represents the variable with the most important impact on a project’s quality, costs and lead time. From the organizational point of view, the matrix structure is frequently chosen for projects. The matrix structure generally coexists with the line structure. The two structures are contrastive. The line structure is based on the unity of command principle and is not open to cooperation and dialogue. The matrix structure encourages cooperation and communication, favours conflict, which is considered here a healthy and essential process. The matrix structure and the line structure claim their right to initiative. Conflict and the multidimensional integration of multiple hierarchies can be negotiated through the concept charisma – mediation, sustained by the matrix structure.

  2. Solubility of sparingly soluble drug derivatives of anthranilic acid.

    Science.gov (United States)

    Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra

    2011-03-24

    This work is a continuation of our systematic study of the solubility of pharmaceuticals (Pharms). All substances here are derivatives of anthranilic acid, and have an anti-inflammatory direction of action (niflumic acid, flufenamic acid, and diclofenac sodium). The basic thermal properties of pure Pharms, i.e., melting and glass-transition temperatures as well as the enthalpy of melting, have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The equilibrium mole fraction solubilities of three pharmaceuticals were measured in a range of temperatures from 285 to 355 K in three important solvents for Pharm investigations: water, ethanol, and 1-octanol using a dynamic method and spectroscopic UV-vis method. The experimental solubility data have been correlated by means of the commonly known G(E) equation: the NRTL, with the assumption that the systems studied here have revealed simple eutectic mixtures. pK(a) precise measurement values have been investigated with the Bates-Schwarzenbach spectrophotometric method. © 2011 American Chemical Society

  3. On the Eigenvalues and Eigenvectors of Block Triangular Preconditioned Block Matrices

    KAUST Repository

    Pestana, Jennifer

    2014-01-01

    Block lower triangular matrices and block upper triangular matrices are popular preconditioners for 2×2 block matrices. In this note we show that a block lower triangular preconditioner gives the same spectrum as a block upper triangular preconditioner and that the eigenvectors of the two preconditioned matrices are related. © 2014 Society for Industrial and Applied Mathematics.

  4. Hamiltonian structure of isospectral deformation equation and semi-classical approximation to factorized S-matrices

    International Nuclear Information System (INIS)

    Chudnovsky, D.V.; Chudnovsky, G.V.

    1980-01-01

    We consider semi-classical approximation to factorized S-matrices. We show that this new class of matrices, called s-matrices, defines Hamiltonian structures for isospectral deformation equations. Concrete examples of factorized s-matrices are constructed and they are used to define Hamiltonian structure for general two-dimensional isospectral deformation systems. (orig.)

  5. Agricultural matrices affect ground ant assemblage composition inside forest fragments.

    Directory of Open Access Journals (Sweden)

    Diego Santana Assis

    Full Text Available The establishment of agricultural matrices generally involves deforestation, which leads to fragmentation of the remaining forest. This fragmentation can affect forest dynamics both positively and negatively. Since most animal species are affected, certain groups can be used to measure the impact of such fragmentation. This study aimed to measure the impacts of agricultural crops (matrices on ant communities of adjacent lower montane Atlantic rainforest fragments. We sampled nine forest fragments at locations surrounded by different agricultural matrices, namely: coffee (3 replicates; sugarcane (3; and pasture (3. At each site we installed pitfall traps along a 500 m transect from the interior of the matrix to the interior of the fragment (20 pitfall traps ~25 m apart. Each transect was partitioned into four categories: interior of the matrix; edge of the matrix; edge of the fragment; and interior of the fragment. For each sample site, we measured ant species richness and ant community composition within each transect category. Ant richness and composition differed between fragments and matrices. Each sample location had a specific composition of ants, probably because of the influence of the nature and management of the agricultural matrices. Species composition in the coffee matrix had the highest similarity to its corresponding fragment. The variability in species composition within forest fragments surrounded by pasture was greatest when compared with forest fragments surrounded by sugarcane or, to a lesser extent, coffee. Functional guild composition differed between locations, but the most representative guild was 'generalist' both in the agricultural matrices and forest fragments. Our results are important for understanding how agricultural matrices act on ant communities, and also, how these isolated forest fragments could act as an island of biodiversity in an 'ocean of crops'.

  6. Agricultural matrices affect ground ant assemblage composition inside forest fragments.

    Science.gov (United States)

    Assis, Diego Santana; Dos Santos, Iracenir Andrade; Ramos, Flavio Nunes; Barrios-Rojas, Katty Elena; Majer, Jonathan David; Vilela, Evaldo Ferreira

    2018-01-01

    The establishment of agricultural matrices generally involves deforestation, which leads to fragmentation of the remaining forest. This fragmentation can affect forest dynamics both positively and negatively. Since most animal species are affected, certain groups can be used to measure the impact of such fragmentation. This study aimed to measure the impacts of agricultural crops (matrices) on ant communities of adjacent lower montane Atlantic rainforest fragments. We sampled nine forest fragments at locations surrounded by different agricultural matrices, namely: coffee (3 replicates); sugarcane (3); and pasture (3). At each site we installed pitfall traps along a 500 m transect from the interior of the matrix to the interior of the fragment (20 pitfall traps ~25 m apart). Each transect was partitioned into four categories: interior of the matrix; edge of the matrix; edge of the fragment; and interior of the fragment. For each sample site, we measured ant species richness and ant community composition within each transect category. Ant richness and composition differed between fragments and matrices. Each sample location had a specific composition of ants, probably because of the influence of the nature and management of the agricultural matrices. Species composition in the coffee matrix had the highest similarity to its corresponding fragment. The variability in species composition within forest fragments surrounded by pasture was greatest when compared with forest fragments surrounded by sugarcane or, to a lesser extent, coffee. Functional guild composition differed between locations, but the most representative guild was 'generalist' both in the agricultural matrices and forest fragments. Our results are important for understanding how agricultural matrices act on ant communities, and also, how these isolated forest fragments could act as an island of biodiversity in an 'ocean of crops'.

  7. Biomimetic matrices for pelvic floor repair

    NARCIS (Netherlands)

    Vashaghian, M.

    2017-01-01

    Pelvic organ prolapsed (POP) is a dysfunctional disease in female pelvic floor that affects a lot of women worldwide, and reduces their quality of life. Currently, trans-vaginal knitted polypropylene meshes are used as secondary treatment, for anatomical correction of the dysfunctional tissues.

  8. Theoretical Properties for Neural Networks with Weight Matrices of Low Displacement Rank

    OpenAIRE

    Zhao, Liang; Liao, Siyu; Wang, Yanzhi; Li, Zhe; Tang, Jian; Pan, Victor; Yuan, Bo

    2017-01-01

    Recently low displacement rank (LDR) matrices, or so-called structured matrices, have been proposed to compress large-scale neural networks. Empirical results have shown that neural networks with weight matrices of LDR matrices, referred as LDR neural networks, can achieve significant reduction in space and computational complexity while retaining high accuracy. We formally study LDR matrices in deep learning. First, we prove the universal approximation property of LDR neural networks with a ...

  9. The Solubility Parameters of Ionic Liquids

    Science.gov (United States)

    Marciniak, Andrzej

    2010-01-01

    The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated. PMID:20559495

  10. The Solubility Parameters of Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Andrzej Marciniak

    2010-04-01

    Full Text Available The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated.

  11. Solubility of Carbon in Nanocrystalline -Iron

    OpenAIRE

    Alexander Kirchner; Bernd Kieback

    2012-01-01

    A thermodynamic model for nanocrystalline interstitial alloys is presented. The equilibrium solid solubility of carbon in -iron is calculated for given grain size. Inside the strained nanograins local variation of the carbon content is predicted. Due to the nonlinear relation between strain and solubility, the averaged solubility in the grain interior increases with decreasing grain size. The majority of the global solubility enhancement is due to grain boundary enrichment however. Therefor...

  12. Hierarchical Matrices Method and Its Application in Electromagnetic Integral Equations

    Directory of Open Access Journals (Sweden)

    Han Guo

    2012-01-01

    Full Text Available Hierarchical (H- matrices method is a general mathematical framework providing a highly compact representation and efficient numerical arithmetic. When applied in integral-equation- (IE- based computational electromagnetics, H-matrices can be regarded as a fast algorithm; therefore, both the CPU time and memory requirement are reduced significantly. Its kernel independent feature also makes it suitable for any kind of integral equation. To solve H-matrices system, Krylov iteration methods can be employed with appropriate preconditioners, and direct solvers based on the hierarchical structure of H-matrices are also available along with high efficiency and accuracy, which is a unique advantage compared to other fast algorithms. In this paper, a novel sparse approximate inverse (SAI preconditioner in multilevel fashion is proposed to accelerate the convergence rate of Krylov iterations for solving H-matrices system in electromagnetic applications, and a group of parallel fast direct solvers are developed for dealing with multiple right-hand-side cases. Finally, numerical experiments are given to demonstrate the advantages of the proposed multilevel preconditioner compared to conventional “single level” preconditioners and the practicability of the fast direct solvers for arbitrary complex structures.

  13. Hypersymmetric functions and Pochhammers of 2×2 nonautonomous matrices

    Directory of Open Access Journals (Sweden)

    A. F. Antippa

    2004-01-01

    Full Text Available We introduce the hypersymmetric functions of 2×2 nonautonomous matrices and show that they are related, by simple expressions, to the Pochhammers (factorial polynomials of these matrices. The hypersymmetric functions are generalizations of the associated elementary symmetric functions, and for a specific class of 2×2 matrices, having a high degree of symmetry, they reduce to these latter functions. This class of matrices includes rotations, Lorentz boosts, and discrete time generators for the harmonic oscillators. The hypersymmetric functions are defined over four sets of independent indeterminates using a triplet of interrelated binary partitions. We work out the algebra of this triplet of partitions and then make use of the results in order to simplify the expressions for the hypersymmetric functions for a special class of matrices. In addition to their obvious applications in matrix theory, in coupled difference equations, and in the theory of symmetric functions, the results obtained here also have useful applications in problems involving successive rotations, successive Lorentz transformations, discrete harmonic oscillators, and linear two-state systems.

  14. Solvated electron structure in glassy matrices

    International Nuclear Information System (INIS)

    Kevan, L.

    1981-01-01

    Current knowledge of the detailed geometrical structure of solvated electrons in aqueous and organic media is summarized. The geometry of solvated electrons in glassy methanol, ethanol, and 2-methyltetrahydrofuran is discussed. Advanced electron magnetic resonance methods and development of new methods of analysis of electron spin echo modulation patterns, second moment line shapes, and forbidden photon spin-flip transitions for paramagnetic species in these disordered systems are discussed. 66 references are cited

  15. Nano-Fiber Reinforced Enhancements in Composite Polymer Matrices

    Science.gov (United States)

    Chamis, Christos C.

    2009-01-01

    Nano-fibers are used to reinforce polymer matrices to enhance the matrix dependent properties that are subsequently used in conventional structural composites. A quasi isotropic configuration is used in arranging like nano-fibers through the thickness to ascertain equiaxial enhanced matrix behavior. The nano-fiber volume ratios are used to obtain the enhanced matrix strength properties for 0.01,0.03, and 0.05 nano-fiber volume rates. These enhanced nano-fiber matrices are used with conventional fiber volume ratios of 0.3 and 0.5 to obtain the composite properties. Results show that nano-fiber enhanced matrices of higher than 0.3 nano-fiber volume ratio are degrading the composite properties.

  16. Square matrices of order 2 theory, applications, and problems

    CERN Document Server

    Pop, Vasile

    2017-01-01

    This unique and innovative book presents an exciting and complete detail of all the important topics related to the theory of square matrices of order 2. The readers exploring every detailed aspect of matrix theory are gently led toward understanding advanced topics. They will follow every notion of matrix theory with ease, accumulating a thorough understanding of algebraic and geometric aspects of matrices of order 2. The prime jewel of this book is its offering of an unusual collection of problems, theoretically motivated, most of which are new, original, and seeing the light of publication for the first time in the literature. Nearly all of the exercises are presented with detailed solutions and vary in difficulty from easy to more advanced. Many problems are particularly challenging. These, and not only these, invite the reader to unleash their creativity and research capabilities and to discover their own methods of attacking a problem. Matrices have a vast practical importance to mathematics, science, a...

  17. Two-mode Gaussian density matrices and squeezing of photons

    International Nuclear Information System (INIS)

    Tucci, R.R.

    1992-01-01

    In this paper, the authors generalize to 2-mode states the 1-mode state results obtained in a previous paper. The authors study 2-mode Gaussian density matrices. The authors find a linear transformation which maps the two annihilation operators, one for each mode, into two new annihilation operators that are uncorrelated and unsqueezed. This allows the authors to express the density matrix as a product of two 1-mode density matrices. The authors find general conditions under which 2-mode Gaussian density matrices become pure states. Possible pure states include the 2-mode squeezed pure states commonly mentioned in the literature, plus other pure states never mentioned before. The authors discuss the entropy and thermodynamic laws (Second Law, Fundamental Equation, and Gibbs-Duhem Equation) for the 2-mode states being considered

  18. A Workshop on Algebraic Design Theory and Hadamard Matrices

    CERN Document Server

    2015-01-01

    This volume develops the depth and breadth of the mathematics underlying the construction and analysis of Hadamard matrices and their use in the construction of combinatorial designs. At the same time, it pursues current research in their numerous applications in security and cryptography, quantum information, and communications. Bridges among diverse mathematical threads and extensive applications make this an invaluable source for understanding both the current state of the art and future directions. The existence of Hadamard matrices remains one of the most challenging open questions in combinatorics. Substantial progress on their existence has resulted from advances in algebraic design theory using deep connections with linear algebra, abstract algebra, finite geometry, number theory, and combinatorics. Hadamard matrices arise in a very diverse set of applications. Starting with applications in experimental design theory and the theory of error-correcting codes, they have found unexpected and important ap...

  19. Asymmetric correlation matrices: an analysis of financial data

    Science.gov (United States)

    Livan, G.; Rebecchi, L.

    2012-06-01

    We analyse the spectral properties of correlation matrices between distinct statistical systems. Such matrices are intrinsically non-symmetric, and lend themselves to extend the spectral analyses usually performed on standard Pearson correlation matrices to the realm of complex eigenvalues. We employ some recent random matrix theory results on the average eigenvalue density of this type of matrix to distinguish between noise and non-trivial correlation structures, and we focus on financial data as a case study. Namely, we employ daily prices of stocks belonging to the American and British stock exchanges, and look for the emergence of correlations between two such markets in the eigenvalue spectrum of their non-symmetric correlation matrix. We find several non trivial results when considering time-lagged correlations over short lags, and we corroborate our findings by additionally studying the asymmetric correlation matrix of the principal components of our datasets.

  20. Asymptotics of eigenvalues and eigenvectors of Toeplitz matrices

    Science.gov (United States)

    Böttcher, A.; Bogoya, J. M.; Grudsky, S. M.; Maximenko, E. A.

    2017-11-01

    Analysis of the asymptotic behaviour of the spectral characteristics of Toeplitz matrices as the dimension of the matrix tends to infinity has a history of over 100 years. For instance, quite a number of versions of Szegő's theorem on the asymptotic behaviour of eigenvalues and of the so-called strong Szegő theorem on the asymptotic behaviour of the determinants of Toeplitz matrices are known. Starting in the 1950s, the asymptotics of the maximum and minimum eigenvalues were actively investigated. However, investigation of the individual asymptotics of all the eigenvalues and eigenvectors of Toeplitz matrices started only quite recently: the first papers on this subject were published in 2009-2010. A survey of this new field is presented here. Bibliography: 55 titles.