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Sample records for liquid water solubility

  1. Water-soluble, triflate-based, pyrrolidinium ionic liquids

    International Nuclear Information System (INIS)

    Moreno, M.; Montanino, M.; Carewska, M.; Appetecchi, G.B.; Jeremias, S.; Passerini, S.

    2013-01-01

    Highlights: • Water-soluble, pyrrolidinium triflate ILs as solvents for extraction processes. • Electrolyte components for high safety, electrochemical devices. • Effect of the oxygen atom in the alkyl main side chain of pyrrolidinium cation. -- Abstract: The physicochemical and electrochemical properties of the water-soluble, N-methoxyethyl-N-methylpyrrolidinium trifluoromethanesulfonate (PYR 1(2O1) OSO 2 CF 3 ) ionic liquid (IL) were investigated and compared with those of commercial N-butyl-N-methylpyrrolidinium trifluoromethanesulfonate (PYR 14 OSO 2 CF 3 ). The results have shown that the transport properties are well correlated with the rheological and thermal behavior. The incorporation of an oxygen atom in the pyrrolidinium cation aliphatic side chain resulted in enhanced flexibility of the ether side chain, this supporting for the higher ionic conductivity, self-diffusion coefficient and density of PYR 1(2O1) OSO 2 CF 3 with respect to PYR 14 OSO 2 CF 3 , whereas no relevant effect on the crystallization of the ionic liquid was found. Finally, the presence of the ether side chain material in the pyrrolidinium cation led to a reduction in electrochemical stability, particularly on the cathodic verse

  2. Kinetics of radiolysis of irradiated ligno celluloses into soluble products in water and rumen liquid

    International Nuclear Information System (INIS)

    Tukenmez, I.; Bakioglu, A.T.; Ersen, M.S.

    1997-01-01

    In order to increase the low bio hydrolysis of ligno celluloses in biotechnological and biological processes where these materials are used as raw materials and ruminant feed, the substrates were pretreated with irradiation to induce radiolytic depolymerisation and then kinetics of their radiolysis into soluble products in water and rumen liquid were analyzed. Wheat straw used as a representative lignocellulose substrate was irradiated at 0-2.5 MGy doses at 20''o''C with an optimum equilibrium humidity of 6.6% in Cs-137 gamma irradiator with a dose rate of 1.8 kGy/h, and soluablefractions in water and in situ rumen liquid were determined gravimetrically. Based on these data, a reaction mechanism was proposed for the radiolysis of ligno celluloses into soluble fractions. From the corresponding reaction rate equations with this mechanism a dose dependent kinetics was derived for the radiolysis of ligno celluloses into water/rumen liquid-soluble products. Defined by this kinetics, the threshold doses for the radiolysis of the substrate into water/rumen liquid-soluble products were respectively found 80.6 kGy and 186.0 kGy, and fractional radiolytic decomposition yields 0.193 MGy''-1''.It was emphasized that developed kinetic models may be used for the process design of irradiation pretreatments to improve the bio hydrolysis of ligno celluloses.(2figs. and 17 refs.)

  3. Solubility limit of methyl red and methylene blue in microemulsions and liquid crystals of water, sds and pentanol systems

    OpenAIRE

    Beri, D.; Pratami, A.; Gobah, P. L.; Dwimala, P.; Amran, A.

    2017-01-01

    Solubility of dyes in amphiphilic association structures of water, SDS and penthanol system (i.e. in the phases of microemulsions and liquid crystals) was attracted much interest due to its wide industrial and technological applications. This research was focused on understanding the solubility limitation of methyl red and methylene blue in microemulsion and liquid crystal phases. Experimental results showed that the highest solubility of methyl red was in LLC, followed by w/o microemulsion a...

  4. Simultaneous detection of water-soluble vitamins using the High Performance Liquid Chromatography (HPLC - a review

    Directory of Open Access Journals (Sweden)

    Rosemond Godbless Dadzie

    2014-01-01

    Full Text Available The water-soluble vitamins (WSV: ascorbic acid (vitamin C, thiamine (B1, riboflavin (B2, niacin (B3, panthothenic acid (B5, pyridoxine, and pyridoxal (B6, folic acid (B9, biotin(B8 , and B12 are very essential in the diet of humankind. As a result of ever increasing pressures from both consumers and legal enforcers, to specify accurately nutritive compositions of WSV that are present in food materials, many researchers have attempted to fill this niche through the provision of highly sensitive and rapid high performance liquid chromatography (HPLC procedures. In view of the health benefits of WSV, a replete of HPLC methods have been developed for simultaneous determination of their contents in nature and fortified food samples, nutritional supplements, as well as blood plasmas. The rate of losses of these vitamins during food processing and analysis, in addition to their transient dynamics, presents complexities in developing a highly sensitive HPLC procedure for their simultaneous separations and assays. This review critically assesses the different HPLC procedures developed by researchers and available in the open literature for simultaneous determination of water-soluble vitamins (WSV in dried tropical fruits materials. The study revealed that not a single chromatographic run developed by researchers can simultaneously elute all the WSV at a time. However, the HPLC procedures that are capable of determining all the WSV were coupled with electrospray ionization mass spectroscopy (ESI-MS, thus making the set-up expensive.

  5. 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...

  6. Simultaneous quantification of 21 water soluble vitamin circulating forms in human plasma by liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Meisser Redeuil, Karine; Longet, Karin; Bénet, Sylvie; Munari, Caroline; Campos-Giménez, Esther

    2015-11-27

    This manuscript reports a validated analytical approach for the quantification of 21 water soluble vitamins and their main circulating forms in human plasma. Isotope dilution-based sample preparation consisted of protein precipitation using acidic methanol enriched with stable isotope labelled internal standards. Separation was achieved by reversed-phase liquid chromatography and detection performed by tandem mass spectrometry in positive electrospray ionization mode. Instrumental lower limits of detection and quantification reached water soluble vitamins in human plasma single donor samples. The present report provides a sensitive and reliable approach for the quantification of water soluble vitamins and main circulating forms in human plasma. In the future, the application of this analytical approach will give more confidence to provide a comprehensive assessment of water soluble vitamins nutritional status and bioavailability studies in humans. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. 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

  8. Improved prediction of octanol-water partition coefficients from liquid-solute water solubilities and molar volumes

    Science.gov (United States)

    Chiou, C.T.; Schmedding, D.W.; Manes, M.

    2005-01-01

    A volume-fraction-based solvent-water partition model for dilute solutes, in which the partition coefficient shows a dependence on solute molar volume (V??), is adapted to predict the octanol-water partition coefficient (K ow) from the liquid or supercooled-liquid solute water solubility (Sw), or vice versa. The established correlation is tested for a wide range of industrial compounds and pesticides (e.g., halogenated aliphatic hydrocarbons, alkylbenzenes, halogenated benzenes, ethers, esters, PAHs, PCBs, organochlorines, organophosphates, carbamates, and amidesureas-triazines), which comprise a total of 215 test compounds spanning about 10 orders of magnitude in Sw and 8.5 orders of magnitude in Kow. Except for phenols and alcohols, which require special considerations of the Kow data, the correlation predicts the Kow within 0.1 log units for most compounds, much independent of the compound type or the magnitude in K ow. With reliable Sw and V data for compounds of interest, the correlation provides an effective means for either predicting the unavailable log Kow values or verifying the reliability of the reported log Kow data. ?? 2005 American Chemical Society.

  9. 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.

  10. 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.

  11. Liquid chromatography with isotope-dilution mass spectrometry for determination of water-soluble vitamins in foods.

    Science.gov (United States)

    Phillips, Melissa M

    2015-04-01

    Vitamins are essential for improving and maintaining human health, and the main source of vitamins is the diet. Measurement of the quantities of water-soluble vitamins in common food materials is important to understand the impact of vitamin intake on human health, and also to provide necessary information for regulators to determine adequate intakes. Liquid chromatography (LC) and mass spectrometry (MS) based methods for water-soluble vitamin analysis are abundant in the literature, but most focus on only fortified foods or dietary supplements or allow determination of only a single vitamin. In this work, a method based on LC/MS and LC/MS/MS has been developed to allow simultaneous quantitation of eight water-soluble vitamins, including multiple forms of vitamins B3 and B6, in a variety of fortified and unfortified food-matrix Standard Reference Materials (SRMs). Optimization of extraction of unbound vitamin forms and confirmation using data from external laboratories ensured accuracy in the assigned values, and addition of stable isotope labeled internal standards for each of the vitamins allowed for increased precision.

  12. Simultaneous determination of eight water-soluble vitamins in supplemented foods by liquid chromatography.

    Science.gov (United States)

    Zafra-Gómez, Alberto; Garballo, Antonio; Morales, Juan C; García-Ayuso, Luis E

    2006-06-28

    A fast, simple, and reliable method for the isolation and determination of the vitamins thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, folic acid, cyanocobalamin, and ascorbic acid in food samples is proposed. The most relevant advantages of the proposed method are the simultaneous determination of the eight more common vitamins in enriched food products and a reduction of the time required for quantitative extraction, because the method consists merely of the addition of a precipitation solution and centrifugation of the sample. Furthermore, this method saves a substantial amount of reagents as compared with official methods, and minimal sample manipulation is achieved due to the few steps required. The chromatographic separation is carried out on a reverse phase C18 column, and the vitamins are detected at different wavelengths by either fluorescence or UV-visible detection. The proposed method was applied to the determination of water-soluble vitamins in supplemented milk, infant nutrition products, and milk powder certified reference material (CRM 421, BCR) with recoveries ranging from 90 to 100%.

  13. Solubility of gallic acid in liquid mixtures of (ethanol + water) from (293.15 to 318.15) K

    International Nuclear Information System (INIS)

    Noubigh, Adel; Jeribi, Chokri; Mgaidi, Arbi; Abderrabba, Manef

    2012-01-01

    Graphical abstract: Solubility of gallic acid vs the mole fraction of ethanol (0.0 to 1) on a solute-free basis in ethanol + water at different temperatures/K. □, 293.15; Δ, 298.15; ◊, 303.15; line calculated by equation. Highlights: ► Solubilities of gallic acid in binary mixtures were determined over the temperatures range (293.15 to 318.15) K. ► The gallic acid solubility in mixed solvents presents a maximum-solubility effect. ► Two empirical equations were proposed to correlate the solubility Data. ► The thermodynamic properties were determined. - Abstract: The solubility of gallic acid in (water + ethanol) binary solvents was determined from (293.15 to 318.15) K at atmospheric pressure using a thermostatted reactor and UV/vis spectrophotometer analysis. The effects of binary solvents composition and temperature on the solubility were discussed. It was found that gallic acid solubility in (water + ethanol) mixed solvents presents a maximum-solubility effect. Two empirical equations were proposed to correlate the solubility data. The calculated solubilities show good agreement with the experimental data within the studied temperature range. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of the gallic acid such as Gibbs energy (Δ sol G°), molar enthalpy of dissolution (Δ sol H°), and molar entropy of dissolution (Δ sol S°) were calculated.

  14. 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

  15. Highly water soluble nanoparticles as a draw solute in forward osmosis for the treatment of radioactive liquid waste

    International Nuclear Information System (INIS)

    Yang, Heeman; Choi, Hye Min; Jang, Sungchan; Seo, Bumkyoung; Lee, Kune Woo; Moon, Jei Kwon

    2014-01-01

    . In this study, we introduced highly water-soluble hyperbranched caroboxylated polyglycerol-coated magnetic nanoparticles (CPG-MNPs). It is known that the highly branched, globular architecture of PG significantly increase solubility compared to linear polymer and they are eco-friendly. The CPG-MNPs showed no aggregate of particles in water even after placing external magnet, and exhibited a high water flux in FO process. The CPG-MNPs are, therefore, potentially useful as a draw solute in FO processes. The operation of nuclear pressurized water reactors (PWRs) results in numerous radioactive waste streams which vary in radioactivity content. Most PWR stations have experienced leakages of boric acid into liquid radioactive waste systems. These wastes contain about 0.3∼0.8 wt% of boric acid. It is known that reverse osmosis (RO) membrane can eliminate boron at high pH and boron of 40∼90% can be removed by RO membrane in pH condition. RO uses hydraulic pressure to oppose, and exceed, the osmotic pressure of an aqueous feed solution containing boric acid. Forward osmosis (FO), a low energy technique based on membrane technologies, has recently garnered attention for its utility in wastewater treatment and desalination applications. In the FO process, water flows across a semi-permeable membrane from a solution with a low osmotic pressure (the feed solution) to a solution with a high osmotic pressure (the draw solution). The driving force in FO processes is provided by the osmotic gradient between the two solutions. Low energy costs and low degrees of membrane fouling are two of the advantages conveyed by FO processes over other processes, such as reverse osmosis processes that rely on a hydraulic pressure driving force. However, the challenges of FO still lie in the fabrication of eligible FO membranes and the readily separable draw solutes of high osmotic pressures. Superparamagnetic Fe3O4 nanoparticles can be separated from water by an external magnet field

  16. Highly water soluble nanoparticles as a draw solute in forward osmosis for the treatment of radioactive liquid waste

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Heeman; Choi, Hye Min; Jang, Sungchan; Seo, Bumkyoung; Lee, Kune Woo; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    . In this study, we introduced highly water-soluble hyperbranched caroboxylated polyglycerol-coated magnetic nanoparticles (CPG-MNPs). It is known that the highly branched, globular architecture of PG significantly increase solubility compared to linear polymer and they are eco-friendly. The CPG-MNPs showed no aggregate of particles in water even after placing external magnet, and exhibited a high water flux in FO process. The CPG-MNPs are, therefore, potentially useful as a draw solute in FO processes. The operation of nuclear pressurized water reactors (PWRs) results in numerous radioactive waste streams which vary in radioactivity content. Most PWR stations have experienced leakages of boric acid into liquid radioactive waste systems. These wastes contain about 0.3∼0.8 wt% of boric acid. It is known that reverse osmosis (RO) membrane can eliminate boron at high pH and boron of 40∼90% can be removed by RO membrane in pH condition. RO uses hydraulic pressure to oppose, and exceed, the osmotic pressure of an aqueous feed solution containing boric acid. Forward osmosis (FO), a low energy technique based on membrane technologies, has recently garnered attention for its utility in wastewater treatment and desalination applications. In the FO process, water flows across a semi-permeable membrane from a solution with a low osmotic pressure (the feed solution) to a solution with a high osmotic pressure (the draw solution). The driving force in FO processes is provided by the osmotic gradient between the two solutions. Low energy costs and low degrees of membrane fouling are two of the advantages conveyed by FO processes over other processes, such as reverse osmosis processes that rely on a hydraulic pressure driving force. However, the challenges of FO still lie in the fabrication of eligible FO membranes and the readily separable draw solutes of high osmotic pressures. Superparamagnetic Fe3O4 nanoparticles can be separated from water by an external magnet field

  17. 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%).

  18. 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

  19. 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.

  20. A novel particle engineering technology to enhance dissolution of poorly water soluble drugs: spray-freezing into liquid.

    Science.gov (United States)

    Rogers, True L; Nelsen, Andrew C; Hu, Jiahui; Brown, Judith N; Sarkari, Marazban; Young, Timothy J; Johnston, Keith P; Williams, Robert O

    2002-11-01

    A novel cryogenic spray-freezing into liquid (SFL) process was developed to produce microparticulate powders consisting of an active pharmaceutical ingredient (API) molecularly embedded within a pharmaceutical excipient matrix. In the SFL process, a feed solution containing the API was atomized beneath the surface of a cryogenic liquid such that the liquid-liquid impingement between the feed and cryogenic liquids resulted in intense atomization into microdroplets, which were frozen instantaneously into microparticles. The SFL micronized powder was obtained following lyophilization of the frozen microparticles. The objective of this study was to develop a particle engineering technology to produce micronized powders of the hydrophobic drug, danazol, complexed with hydroxypropyl-beta-cyclodextrin (HPbetaCD) and to compare these SFL micronized powders to inclusion complex powders produced from other techniques, such as co-grinding of dry powder mixtures and lyophilization of bulk solutions. Danazol and HPbetaCD were dissolved in a water/tetrahydrofuran cosolvent mixture prior to SFL processing or slow freezing. Identical quantities of the API and HPbetaCD used in the solutions were co-ground in a mortar and pestle and blended to produce a co-ground physical mixture for comparison. The powder samples were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy, surface area analysis, and dissolution testing. The results provided by DSC, XRD, and FTIR suggested the formation of inclusion complexes by both slow-freezing and SFL. However, the specific surface area was significantly higher for the latter. Dissolution results suggested that equilibration of the danazol/HPbetaCD solution prior to SFL processing was required to produce the most soluble conformation of the resulting inclusion complex following SFL. SFL micronized powders exhibited better dissolution

  1. Determination of water-soluble and fat-soluble vitamins in tears and blood serum of infants and parents by liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Khaksari, Maryam; Mazzoleni, Lynn R; Ruan, Chunhai; Kennedy, Robert T; Minerick, Adrienne R

    2017-02-01

    Tears serve as a viable diagnostic fluid with advantages including less invasive sample to collect and less complex to prepare for analysis. Several water-soluble and fat-soluble vitamins were detected and quantified in human tears and compared with blood serum levels. Samples from 15 family pairs, each pair consisting of a four-month-old infant and one parent were analyzed; vitamin concentrations were compared between tears and blood serum for individual subjects, between infants and parents, and against self-reported dietary intakes. Water-soluble vitamins B 1 , B 2 , B 3 (nicotinamide), B 5 , B 9 and fat-soluble vitamin E (α-tocopherol) were routinely detected in tears and blood serum while fat-soluble vitamin A (retinol) was detected only in blood serum. Water-soluble vitamin concentrations measured in tears and blood serum of single subjects were comparable, while higher concentrations were measured in infants compared to their parents. Fat-soluble vitamin E concentrations were lower in tears than blood serum with no significant difference between infants and parents. Serum vitamin A concentrations were higher in parents than infants. Population trends were compiled and quantified using a cross correlation factor. Strong positive correlations were found between tear and blood serum concentrations of vitamin E from infants and parents and vitamin B 3 concentrations from parents, while slight positive correlations were detected for infants B 3 and parents B 1 and B 2 concentrations. Correlations between infants and parents were found for the concentrations of B 1 , B 2 , B 3 , and E in tears, and the concentrations of B 2, A, and E in blood serum. Stronger vitamin concentration correlations were found between infants and parents for the breast-fed infants, while no significant difference was observed between breast-fed and bottle-fed infants. This work is the first to demonstrate simultaneous vitamin A, B, and E detection and to quantify correlations between

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-01

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

  3. Thermodynamics of the sorption of water-soluble vitamins in reverse-phase high performance liquid chromatography

    Science.gov (United States)

    Chirkin, V. A.; Karpov, S. I.; Selemenev, V. F.

    2012-12-01

    The thermodynamics of the sorption of certain water-soluble vitamins on a C18 reverse phase from water-acetonitrile solutions of different compositions is studied. The thermodynamic characteristics of the investigated chromatographic systems are calculated. The dependences of standard molar enthalpy and changes in entropy when the sorbate transfers from the bulk solution to the surface layer on the concentration of the organic component in the mobile phase are analyzed. The boundaries for applying the main retention models describing the sorption of the investigated compounds are discussed.

  4. An ionic liquid-in-water microemulsion as a potential carrier for topical delivery of poorly water soluble drug: Development, ex-vivo and in-vivo evaluation.

    Science.gov (United States)

    Goindi, Shishu; Kaur, Ramanpreet; Kaur, Randeep

    2015-11-30

    In this paper, we report an ionic liquid-in-water (IL/w) microemulsion (ME) formulation which is able to solubilize etodolac (ETO), a poorly water soluble drug for topical delivery using BMIMPF6 (1-butyl-3-methylimidazolium hexafluorophosphate) as IL, Tween 80 as surfactant and ethanol as co-surfactant. The prepared ME was characterized for physicochemical parameters, subjected to ex-vivo permeation studies as well as in-vivo pharmacodynamic evaluation. The ex-vivo drug permeation studies through rat skin was performed using Franz-diffusion cell and the IL/w based ME showed maximum mean cumulative percent permeation of 99.030±0.921% in comparison to oil-in-water (o/w) ME (61.548±1.875%) and oily solution (48.830±2.488%) of ETO. In-vivo anti-arthritic and anti-inflammatory activities of the prepared formulations were evaluated using different rodent models and the results revealed that ETO loaded IL/w based ME was found to be more effective in controlling inflammation than oily solution, o/w ME and marketed formulation of ETO. Histopathological studies also demonstrated that IL/w based ME caused no anatomical and pathological changes in the skin. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Solubility of iron in liquid lead

    International Nuclear Information System (INIS)

    Ali-Khan, I.

    1981-01-01

    The use of liquid lead in high temperature chemical and metallurgical processes is well known. The structural materials applied for the containment of these processes are either iron base alloys or possess iron as an alloying element. Besides that, lead itself is alloyed in some steels to achieve some very useful properties. For understanding the effect of liquid lead in such structural materials, it is important to determine the solubility of iron in liquid lead which would also be indicative of the stability of these alloys. At the institute of reactor materials of KFA Juelich, investigations have been conducted to determine the solubility of iron in liquid lead up to a temperature of about 1000 0 C. In this presentation the data concerning the solubility of iron in liquid lead are brought up to date and discussed including the results of our previous investigations. (orig.)

  6. Sequential determination of fat- and water-soluble vitamins in Rhodiola imbricata root from trans-Himalaya with rapid resolution liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Tayade, Amol B; Dhar, Priyanka; Kumar, Jatinder; Sharma, Manu; Chaurasia, Om P; Srivastava, Ravi B

    2013-07-30

    A rapid method was developed to determine both types of vitamins in Rhodiola imbricata root for the accurate quantification of free vitamin forms. Rapid resolution liquid chromatography/tandem mass spectrometry (RRLC-MS/MS) with electrospray ionization (ESI) source operating in multiple reactions monitoring (MRM) mode was optimized for the sequential analysis of nine water-soluble vitamins (B1, B2, two B3 vitamins, B5, B6, B7, B9, and B12) and six fat-soluble vitamins (A, E, D2, D3, K1, and K2). Both types of vitamins were separated by ion-suppression reversed-phase liquid chromatography with gradient elution within 30 min and detected in positive ion mode. Deviations in the intra- and inter-day precision were always below 0.6% and 0.3% for recoveries and retention time. Intra- and inter-day relative standard deviation (RSD) values of retention time for water- and fat-soluble vitamin were ranged between 0.02-0.20% and 0.01-0.15%, respectively. The mean recoveries were ranged between 88.95 and 107.07%. Sensitivity and specificity of this method allowed the limits of detection (LOD) and limits of quantitation (LOQ) of the analytes at ppb levels. The linear range was achieved for fat- and water-soluble vitamins at 100-1000 ppb and 10-100 ppb. Vitamin B-complex and vitamin E were detected as the principle vitamins in the root of this adaptogen which would be of great interest to develop novel foods from the Indian trans-Himalaya. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. 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.

  8. High pressure liquid chromatographic method for the separation and quantitation of water-soluble radiolabeled benzene metabolites

    International Nuclear Information System (INIS)

    Sabourin, P.J.; Bechtold, W.E.; Henderson, R.F.

    1988-01-01

    The glucuronide and sulfate conjugates of benzene metabolite as well as muconic acid and pre-phenyl- and phenylmercapturic acids were separated by ion-pairing HPLC. The HPLC method developed was suitable for automated analysis of a large number of tissue or excreta samples. p-Nitrophenyl [ 14 C]glucuronide was used as an internal standard for quantitation of these water-soluble metabolites. Quantitation was verified by spiking liver tissue with various amounts of phenylsulfate or glucuronides of phenol, catechol, or hydroquinone and analyzing by HPLC. Values determined by HPLC analysis were within 10% of the actual amount with which the liver was spiked. The amount of metabolite present in urine following exposure to [ 3 H]benzene was determined using p-nitrophenyl [ 14 C]glucuronide as an internal standard. Phenylsulfate was the major water-soluble metabolite in the urine of F344 rats exposed to 50 ppm [ 3 H]benzene for 6 h. Muconic acid and an unknown metabolite which decomposed in acidic media to phenylmercapturic acid were also present. Liver, however, contained a different metabolic profile. This indicates that urinary metabolite profiles may not be a true reflection of what is seen in individual tissues

  9. 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

  10. Determination of water-soluble vitamins in infant milk and dietary supplement using a liquid chromatography on-line coupled to a corona-charged aerosol detector.

    Science.gov (United States)

    Márquez-Sillero, Isabel; Cárdenas, Soledad; Valcárcel, Miguel

    2013-10-25

    A simple and rapid method for the simultaneous determination of seven water-soluble vitamins (thiamine, folic acid, nicotinic acid, ascorbic acid, pantothenic acid, pyridoxine and biotin) was developed by high performance liquid chromatographic separation and corona-charged aerosol detection. The water-soluble vitamins were separated on a Lichrosorb RP-C18 column under isocratic conditions with a mobile phase consisting of 0.05 M ammonium acetate:methanol 90:10 (v/v) at the flow rate 0.5 mL min(-1). The vitamins were extracted from the infant milk (liquid and powder format) using a precipitation step with 2.5 M acetic acid remaining the analyte in the supernatant. As far as dietary supplements are concerned, only a dilution with distilled water was required. The detection limits ranged from 0.17 to 0.62 mg L(-1) for dietary supplements and 1.7 to 6.5 mg L(-1) for milk samples. The precision of the method was evaluated in terms of relative standard deviation (%, RSD) under repeatability and reproducibility conditions, being the average values for each parameter 2.6 and 2.7 for dietary supplements and 4.3 and 4.6 for milk samples. The optimized method was applied to different infant milk samples and dietary supplements. The results of the analysis were in good agreement with the declared values. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. 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

  12. Correlation of Helium Solubility in Liquid Nitrogen

    Science.gov (United States)

    VanDresar, Neil T.; Zimmerli, Gregory A.

    2012-01-01

    A correlation has been developed for the equilibrium mole fraction of soluble gaseous helium in liquid nitrogen as a function of temperature and pressure. Experimental solubility data was compiled and provided by National Institute of Standards and Technology (NIST). Data from six sources was used to develop a correlation within the range of 0.5 to 9.9 MPa and 72.0 to 119.6 K. The relative standard deviation of the correlation is 6.9 percent.

  13. Lidocaine self-sacrificially improves the skin permeation of the acidic and poorly water-soluble drug etodolac via its transformation into an ionic liquid.

    Science.gov (United States)

    Miwa, Yasushi; Hamamoto, Hidetoshi; Ishida, Tatsuhiro

    2016-05-01

    Poor transdermal penetration of active pharmaceutical ingredients (APIs) impairs both bioavailability and therapeutic benefits and is a major challenge in the development of transdermal drug delivery systems. Here, we transformed a poorly water-soluble drug, etodolac, into an ionic liquid in order to improve its hydrophobicity, hydrophilicity and skin permeability. The ionic liquid was prepared by mixing etodolac with lidocaine (1:1, mol/mol). Both the free drug and the transformed ionic liquid were characterized by differential scanning colorimetry (DSC), infrared spectroscopy (IR), and saturation concentration measurements. In addition, in vitro skin-permeation testing was carried out via an ionic liquid-containing patch (Etoreat patch). The lidocaine and etodolac in ionic liquid form led to a relatively lower melting point than either lidocaine or etodolac alone, and this improved the lipophilicity/hydrophilicity of etodolac. In vitro skin-permeation testing demonstrated that the Etoreat patch significantly increased the skin permeation of etodolac (9.3-fold) compared with an etodolac alone patch, although an Etoreat patch did not increase the skin permeation of lidocaine, which was consistent with the results when using a lidocaine alone patch. Lidocaine appeared to self-sacrificially improve the skin permeation of etodolac via its transformation into an ionic liquid. The data suggest that ionic liquids composed of approved drugs may substantially expand the formulation preparation method to meet the challenges of drugs which are characterized by poor rates of transdermal absorption. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Ionic-liquid-induced microfluidic reaction for water-soluble Ce1-xTbxF3 nanocrystal synthesis

    International Nuclear Information System (INIS)

    Xie Nan; Luan Weiling

    2011-01-01

    Luminescent lanthanide nanocrystals (NCs) are proposed to be a promising new class of fluorescent labeling agents due to their attractive optical and chemical features including low toxicity, wide photoluminescence (PL) emission and high resistance to photobleaching. In this paper, an ionic-liquid-induced synthesis of Ce 1-x Tb x F 3 nanoparticle was investigated via utilizing a capillary microreactor. Ionic liquid-[bmim]BF 4 acts as both a fluoride source and stabilizing solvent during the reaction, which was shown to be a key factor that governs luminescence intensity of the obtained nanoparticles. The luminescent properties can be greatly improved by optimizing the volume percentage of [bmim]BF 4 . Furthermore, the reaction temperature exerts an influence on the properties of the prepared samples. Experimental results show that the colloidal solutions of Tb 3+ -doped CeF 3 NCs exhibit the characteristic emission of Ce 3+ 5d-4f and Tb 3+5 D 4 - 7 F J (J = 6-3) transitions with 5 D 4 - 7 F 5 green emission at 542 nm as the strongest peak. The as-prepared samples are found dispersible in water with the quantum yield (in aqueous solution) as 12%, which indicates a potential application on biolabels, light-emitting diodes (LEDs) and redox luminescent switches.

  15. Simultaneous analysis for water- and fat-soluble vitamins by a novel single chromatography technique unifying supercritical fluid chromatography and liquid chromatography.

    Science.gov (United States)

    Taguchi, Kaori; Fukusaki, Eiichiro; Bamba, Takeshi

    2014-10-03

    Chromatography techniques usually use a single state in the mobile phase, such as liquid, gas, or supercritical fluid. Chromatographers manage one of these techniques for their purpose but are sometimes required to use multiple methods, or even worse, multiple techniques when the target compounds have a wide range of chemical properties. To overcome this challenge, we developed a single method covering a diverse compound range by means of a "unified" chromatography which completely bridges supercritical fluid chromatography and liquid chromatography. In our method, the phase state was continuously changed in the following order; supercritical, subcritical and liquid. Moreover, the gradient of the mobile phase starting at almost 100% CO2 was replaced with 100% methanol at the end completely. As a result, this approach achieved further extension of the polarity range of the mobile phase in a single run, and successfully enabled the simultaneous analysis of fat- and water-soluble vitamins with a wide logP range of -2.11 to 10.12. Furthermore, the 17 vitamins were exceptionally separated in 4min. Our results indicated that the use of dense CO2 and the replacement of CO2 by methanol are practical approaches in unified chromatography covering diverse compounds. Additionally, this is a first report to apply the novel approach to unified chromatography, and can open another door for diverse compound analysis in a single chromatographic technique with single injection, single column and single system. Copyright © 2014. Published by Elsevier B.V.

  16. Simultaneous determination of four water-soluble vitamins in fortified infant foods by ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry.

    Science.gov (United States)

    Lu, Baiyi; Ren, Yiping; Huang, Baifen; Liao, Wenqun; Cai, Zengxuan; Tie, Xiaowei

    2008-03-01

    A novel ultra-performance liquid chromatography electrospray ionization tandem triple quadrupole mass spectrometry method for the simultaneous determination of four water-soluble vitamins, including vitamin B5 (VB5), vitamin B8 (VB8), vitamin B9 (VB9), and vitamin B12 (VB12) in fortified infant foods is developed and validated. A reverse phase UPLC separation system consisting of a Waters ACQUITY UPLC BEH C-18 column (2.1 mm x 100 mm i.d., 1.7 microm) and a binary gradient acetonitrile-water mobile phase is applied for the separation of the four water-soluble vitamins. Formic acid is spiked into the mobile phase to enhance the ionization efficiency. Tandem MS-MS analysis is performed in multi-reaction monitoring mode (MRM). Product-ion traces at m/z 220.1 --> 89.9 for VB5, 245.1 --> 227.1 for VB8, 442.3 --> 295.2 for VB9, and 678.9 --> 147.0 for VB12 are used for quantitation of the corresponding vitamins, and traces at m/z 455.5 --> 308.0 are used for methotrexate (internal standard). Limits of quantitation (LOQs) are 0.016, 0.090, 0.020, and 0.019 microg/L for VB5, VB8, VB9, and VB12, respectively. Intra- and inter-day precisions for the determination of the four vitamins are better than 6.84% and 12.26% in relative standard deviations, and recoveries for the four vitamins are in the range of 86.0~101.5%. The developed approach is applied for the determination of the trace amounts of the vitamins in fortified milk powers and fortified rice powers.

  17. Solubility of lithium deuteride in liquid lithium

    International Nuclear Information System (INIS)

    Veleckis, E.; Yonco, R.M.; Maroni, V.A.

    1977-01-01

    The solubility of LiD in liquid lithium between the eutectic and monotectic temperatures was measured using a direct sampling method. Solubilities were found to range from 0.0154 mol.% LiD at 199 0 C to 3.32 mol.% LiD at 498 0 C. The data were used in the derivation of an expression for the activity coefficient of LiD as a function of temperature and composition and an equation relating deuteride solubility and temperature, thus defining the liquidus curve. Similar equations were also derived for the Li-LiH system using the existing solubility data. Extrapolation of the liquidus curves yielded the eutectic concentrations (0.040 mol.% LiH and 0.035 mol.% LiD) and the freezing point depressions (0.23 0 C for Li-LiH and 0.20 0 C for Li-LiD) at the eutectic point. The results are compared with the literature data for hydrogen and deuterium. The implications of the relatively high solubility of hydrogen isotopes in lithium just above the melting point are discussed with respect to the cold trapping of tritium in fusion reactor blankets. (Auth.)

  18. Solubility of krypton in liquid CO2

    International Nuclear Information System (INIS)

    Notz, K.J.; Meservey, A.B.

    1976-06-01

    The solubility of krypton in liquid CO 2 was measured experimentally over essentially the entire liquid range of CO 2 , from -53 to 29 0 C. A tracer technique using 85 Kr was employed, and equilibrated gas-liquid samples were analyzed in situ with a collimated counter. Dilute concentrations of krypton were used, and the data are expressed as a distribution ratio, Y/sub Kr//X/sub Kr/, the log of which is nearly linear with respect to temperature from the lowest temperature to about 20 0 C, above which the values fall off rapidly toward a value of unity at the critical temperature. The numerical values obtained for the distribution ratio increase from 1.44 at 29 0 C to 29.4 at -53 0 C

  19. Novel liquid application systems for poorly soluble drugs

    OpenAIRE

    Luschmann, Christoph Roman

    2015-01-01

    This thesis was focused on the development of efficient novel liquid formulations for poorly water soluble drugs for the treatment of inflammatory ophthalmic diseases. With Restasis® there is currently only one drug product approved by the FDA, in the US only, for the treatment of dry eye syndrome. It still suffers from low bioavailability, bad biocompatibility and thus a low patient compliance, as well as cumbersome manufacturing. Hence, there is a tremendous lack in the options for a causal...

  20. The Hildebrand solubility parameters of ionic liquids-part 2.

    Science.gov (United States)

    Marciniak, Andrzej

    2011-01-01

    The Hildebrand solubility parameters have been calculated for eight ionic liquids. Retention data from the inverse gas chromatography measurements of the activity coefficients at infinite dilution were used for the calculation. From the solubility parameters, the enthalpies of vaporization of ionic liquids were estimated. Results are compared with solubility parameters estimated by different methods.

  1. Larvicidal Activity of A Mixture of Cashew Nut Shell Liquid and Water-Soluble Extract of Soap Nut Fruit (Sapindus rarak DC. Against 3rd Instar Larvae of Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Glory Resia Raraswati

    2015-10-01

    Full Text Available Cashew Nut Shell Liquid (CNSL which has been known as a waste of processing cashew fruits which is contain phenolic compounds have activity as larvicides. Cashew nut shell liquid is not soluble in the water where the larvae grow. Cashew nut shell liquid mixed with water-soluble extract of soapnut fruit which serves as a natural surfactant that can emulsify oil in water. The test subjects were larvae of Aedes aegypti third instar. Test subjects were divided into treatment group and control group. In the treatment group, test subjects were  the mixture of CNSL and Ethylacetat Soluble Extract (ESE in tap water. The Larvae mortality observations were done 24 hours after the treatment. LC50 and LC90 as final test data were analyzed using probit analysis. Extract constituents   of CNSL and Water Soluble Extract of SoapNut fruit (WSEoSN were  investigated using Thin Layer Chromatography (TLC method. The effect of CNSL as larvicides against third instar larvae of Ae. aegypti with were LC50 of 14,12 ppm, while the LC90 of 24,85 ppm.

  2. Synthesis, Structural Analysis and Antimicrobial Activities of Novel Water Soluble Ionic Liquids Derived from N-Heterocyclic Carbene Salts

    Directory of Open Access Journals (Sweden)

    Ahmet Kunduracıoğlu

    2016-06-01

    Full Text Available Six N-heterocyclic Carbene based Ionic Liquids (ILs have been synthesized by conventional methods. The ILs were spectroscopically characterized by NMR and FT-IR techniques. Their in vitro antimicrobial activities were determined towards gram-positive and gram-negative bacterias and yeast strains using minimum inhibition concentration (MIC assay. The best inhibition performances were obtained with compound 1 due to its more hydrophilic nature compared with the others. It exhibited 1 mg L–1 MIC value against to the most bacteria while the others showed 4 mg L–1. This work is licensed under a Creative Commons Attribution 4.0 International License.

  3. 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

  4. Simultaneous determination of water-soluble vitamins in SRM 1849 Infant/Adult Nutritional Formula powder by liquid chromatography-isotope dilution mass spectrometry.

    Science.gov (United States)

    Goldschmidt, Robert J; Wolf, Wayne R

    2010-05-01

    Assessing dietary intake of vitamins from all sources, including foods, dietary supplements, and fortified foods, would be aided considerably by having analytical methodologies that are capable of simultaneous determination of several vitamins. Vitamins naturally present in foods may occur in different chemical forms, with levels ranging over several orders of magnitude. Vitamins in dietary supplements and fortified foods, however, are typically added in a single chemical form, and matrix issues are usually not as complex. These sources should thus be relatively amenable to approaches that aim for simultaneous determination of multiple vitamins. Our recent work has focused on development of liquid chromatography (LC)-UV/fluorescence and LC-tandem mass spectrometry methods for the simultaneous determination of water-soluble vitamins (thiamine, niacin, pyridoxine, pantothenic acid, folic acid, biotin, and riboflavin) in dietary supplement tablets and fortified foods, such as formula powders and breakfast cereals. As part of the validation of our methods and collaboration in characterization of a new NIST SRM 1849 Infant/Adult Nutritional Formula powder, we report data on SRM 1849 using isotope dilution mass spectrometric methods. Use of available NIST Standard Reference Materials(R) as test matrices in our method development and validation gives a benchmark for future application of these methods. We compare three chromatographic approaches and provide data on stability of vitamin standard solutions for LC-based multiple vitamin determinations.

  5. Novel ultra-cryo milling and co-grinding technique in liquid nitrogen to produce dissolution-enhanced nanoparticles for poorly water-soluble drugs.

    Science.gov (United States)

    Sugimoto, Shohei; Niwa, Toshiyuki; Nakanishi, Yasuo; Danjo, Kazumi

    2012-01-01

    A novel ultra-cryo milling micronization technique for pharmaceutical powders using liquid nitrogen (LN2 milling) was used to grind phenytoin, a poorly water-soluble drug, to improve its dissolution rate. LN2 milling produced particles that were much finer and more uniform in size and shape than particles produced by jet milling. However, the dissolution rate of LN2-milled phenytoin was the same as that of unground phenytoin due to agglomeration of the submicron particles. To overcome this, phenytoin was co-ground with polyvinylpyrrolidone (PVP). The dissolution rate of co-ground phenytoin was much higher than that of original phenytoin, single-ground phenytoin, a physical mixture of phenytoin and PVP, or jet-milled phenytoin. X-Ray diffraction showed that the crystalline state of mixtures co-ground by LN2 milling remained unchanged. The equivalent improvement in dissolution, whether phenytoin was co-ground or separately ground and then mixed with PVP, suggested that even when co-ground, the grinding of PVP and phenytoin occurs essentially independently. Mixing original PVP with ground phenytoin provided a slight improvement in dissolution, indicating that the particle size of PVP is important for improving dissolution. When mixed with ground phenytoin, PVP ground by LN2 milling aided the wettability and dispersion of phenytoin, enhancing utilization of the large surface area of ground phenytoin. Co-grinding phenytoin with other excipients such as Eudragit L100, hypromellose, hypromellose acetate-succinate, microcrystalline cellulose, hydroxypropylcellulose and carboxymethyl cellulose also improved the dissolution profile, indicating an ultra-cryo milling and co-grinding technique in liquid nitrogen has a broad applicability of the dissolution enhancement of phenytoin.

  6. Solubility of xenon in liquid sodium

    International Nuclear Information System (INIS)

    Veleckis, E.; Cafasso, F.A.; Feder, H.M.

    1976-01-01

    The solubility of xenon in liquid sodium was measured as a function of pressure (2-8 atm) and temperature (350-600 0 C). Henry's law was obeyed with the value of the Henry's law constant, K/sub H/ = N/sub Xe//P, ranging from 1.38 x 10 -10 atm -1 at 350C, to 1.59 x 10 -8 atm -1 at 600 0 C where N/sub Xe/ and P are the atom fraction and the partial pressure of xenon, respectively. The temperature dependence of solubility may be represented by log 10 lambda = (0.663 +- 0.01) - (4500 +- 73) T -1 , where lambda is the Ostwald coefficient (the volume of xenon dissolved per unit volume of sodium at the temperature of the experiment). The heat of solution of xenon in sodium was 20.6 +- 0.7 kcal/mole, where the standard state of xenon is defined as that of 1 mole of an ideal gas, confined to a volume equal to the molar volume of sodium

  7. The use of surfactants to enhance the solubility and stability of the water-insoluble anticancer drug SN38 into liquid crystalline phase nanoparticles.

    Science.gov (United States)

    Ranneh, Abdul-Hackam; Iwao, Yasunori; Noguchi, Shuji; Oka, Toshihiko; Itai, Shigeru

    2016-12-30

    Cubosomes were used to increase the aqueous solubility of the water insoluble anticancer drug SN38. The results showed that the use of a common cubosome formulation consisting of phytantriol (PHYT) as the matrix amphiphile (PHYT-cubosome) led to a 6-fold increase in the solubility of SN38. However, mean hydrodynamic diameter (D H ) and polydispersity index (PDI) of these PHYT-cubosome particles were 345±49nm and 0.37±0.05, respectively, making them unsuitable for intravenous applications. Several additives were investigated to increase the solubility of SN38 and reduce the D H and PDI values of the resulting particles. Charged additives such as didodecyldimethyl ammonium bromide (DDAB) and sodium dodecyl sulfate (SDS) led to improvements in the physiochemical properties of the cubosomes. Notably, the PHYT-DDAB and PHT-SDS cubosomes led to 15- and 14-fold increases in the aqueous solubility of SN38, respectively. Moreover, the SN38 loaded into the PHYT-DDAB and PHYT-SDS cubosomes was found to be highly stable, with very little hydrolysis to its inactive acid form. In summary, the addition of DDAB and SDS to PHYT-cubosome nanoparticle drug delivery systems not only led to considerable improvements in their physiochemical properties, but also enhanced the aqueous solubility of SN38 and increased its chemical stability. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Experimental solubility measurements of lanthanides in liquid alkalis

    Science.gov (United States)

    Isler, Jeremy; Zhang, Jinsuo; Mariani, Robert; Unal, Cetin

    2017-11-01

    In metallic nuclear fuel, lanthanide fission products play a crucial role in the fuel burnup-limiting phenomena of fuel cladding-chemical interaction (FCCI). The lanthanides have been hypothesized to transport by a 'liquid-like' mechanism out of the metallic fuel to the fuel peripheral to cause FCCI. By liquid fission product cesium and liquid bond sodium, the lanthanides are transported to the peripheral of the fuel through the porosity of the fuel. This work investigates the interaction between the lanthanides and the alkali metals by experimentally measuring the solubility of lanthanides within liquid sodium, and neodymium in liquid cesium and mixtures of cesium and sodium. The temperature dependence of the solubility is experimentally determined within an inert environment. In addition, the dependence of the solubility on the alkali metal concentration in liquid mixtures of cesium and sodium was examined. In quantifying the solubility, the fundamental understanding of this transport mechanism can be better determined.

  9. Water Soluble Polymers for Pharmaceutical Applications

    Directory of Open Access Journals (Sweden)

    Veeran Gowda Kadajji

    2011-11-01

    Full Text Available Advances in polymer science have led to the development of novel drug delivery systems. Some polymers are obtained from natural resources and then chemically modified for various applications, while others are chemically synthesized and used. A large number of natural and synthetic polymers are available. In the present paper, only water soluble polymers are described. They have been explained in two categories (1 synthetic and (2 natural. Drug polymer conjugates, block copolymers, hydrogels and other water soluble drug polymer complexes have also been explained. The general properties and applications of different water soluble polymers in the formulation of different dosage forms, novel delivery systems and biomedical applications will be discussed.

  10. The solubility of metals in Pb-17Li liquid alloy

    International Nuclear Information System (INIS)

    Borgstedt, H.U.; Feuerstein, H.

    1992-01-01

    The solubility data of iron in the eutectic alloy Pb-17Li which were evaluated from corrosion tests in a turbulent flow of the molten alloy are discussed in the frame of solubilities of the transition metals in liquid lead. It is shown that the solubility of iron in the alloy is close to that in lead. This is also the fact for several other alloying elements of steels. A comparison of all known data shows that they are in agreement with generally shown trends for the solubility of the transition metals in low melting metals. These trends indicate comparably high solubilities of nickel and manganese in the liquid metals, lower saturation concentration of vanadium, chromium, iron, and cobalt, and extremely low solubility of molybdenum. (orig.)

  11. Solubilities of boric acid in heavy water

    International Nuclear Information System (INIS)

    Nakai, Shigetsugu; Aoi, Hideki; Hayashi, Ken-ichi; Katoh, Taizo; Watanabe, Takashi.

    1988-01-01

    A gravimetric analysis using meta-boric acid (HBO 2 or DBO 2 ) as a weighing form has been developed for solubility measurement. The method gave satisfactory results in preliminary measurement of solubilities of boric acid in light water. By using this method, the solubilities of 10 B enriched D 3 BO 3 in heavy water were measured. The results are as follows; 2.67 (7deg C), 3.52 (15deg C), 5.70 (30deg C), 8.87 (50deg C) and 12.92 (70deg C) w/o, respectively. These values are about 10% lower than those in light water. Thermodynamical consideration based on the data shows that boric acid is the water structure breaker. (author)

  12. Simultaneous determination of some water-soluble vitamins and preservatives in multivitamin syrup by validated stability-indicating high-performance liquid chromatography method.

    Science.gov (United States)

    Vidović, Stojanka; Stojanović, Biljana; Veljković, Jelena; Prazić-Arsić, Ljiljana; Roglić, Goran; Manojlović, Dragan

    2008-08-22

    HPLC stability-indicating method has been developed for the simultaneous determination of some water-soluble vitamins (ascorbic acid, thiamine hydrochloride, riboflavin-5'-phosphate sodium, pyridoxine hydrochloride, nicotinamide, D(+)-panthenol) and two preservatives (methylparaben and sodium benzoate) in multivitamin syrup preparation. Water-soluble vitamins, preservatives and their degradants were separated on Zorbax SB-Aq (C(18)) (250 mm x 4.6 mm, 5 microm) column at an ambient temperature. Combined isocratic and gradient elution was performed with a mobile phase consisting of 0.0125 M hexane-1-sulfonic acid sodium salt in 0.1% (m/v) o-phosphoric acid, pH 2.4-2.5 (solvent A) and acetonitrile (solvent B) at the flow-rate 1 ml min(-1). Starting with solvent A an isocratic elution was performed for 15 min, then the composition was changed to 85% of A and 15% of B during the next 20 min and it was constant for 5 min, then the composition was changed to 70% of A and 30% of B during next 15 min and it was constant for 5 min and finally was changed to 100% of A as at the beginning of the elution. Detection was performed with diode array detector at 210, 230 and 254 nm. Multivitamin syrup preparation was subjected to stress testing (forced degradation) in order to demonstrate that degradants from the vitamins, preservatives and/or product excipients do not interfere with the quantification of vitamins and preservatives. Typical validation characteristics: selectivity, accuracy, precision, linearity, range, limit of quantification and limit of detection were evaluated for vitamins and preservatives.

  13. Solubility of inorganic salts in pure ionic liquids

    International Nuclear Information System (INIS)

    Pereiro, A.B.; Araújo, J.M.M.; Oliveira, F.S.; Esperança, J.M.S.S.; Canongia Lopes, J.N.; Marrucho, I.M.; Rebelo, L.P.N.

    2012-01-01

    Highlights: ► We report the solubility of different conventional salts in several ionic liquids. ► The solubility was initially screened using a visual detection method. ► The most promising mixtures were quantitatively re-measured using an ATR–FTIR. - Abstract: The solubility of different conventional salts in several room-temperature ionic liquids – containing ammonium, phosphonium or imidazolium cations combined with acetate, sulfate, sulfonate, thiocyanate, chloride, tetracyano-borate, tris(pentafluoroethyl)trifluoro-phosphate, L-lactate, bis(trifluoromethylsulfonyl)imide or trifluoromethylsulfonate anions – were screened using a visual detection method. The most promising mixtures were then re-measured using an ATR–FTIR (Attenuated Total Reflection Fourier Transform Infra Red) spectroscopy technique in order to accurately and quantitatively determine the corresponding solubility at 298.15 K.

  14. Solubility of carbohydrates in heavy water.

    Science.gov (United States)

    Cardoso, Marcus V C; Carvalho, Larissa V C; Sabadini, Edvaldo

    2012-05-15

    The solubility of several mono-(glucose and xylose), di-(sucrose and maltose), tri-(raffinose) and cyclic (α-cyclodextrin) saccharides in H(2)O and in D(2)O were measured over a range of temperatures. The solution enthalpies for the different carbohydrates in the two solvents were determined using the vant' Hoff equation and the values in D(2)O are presented here for the first time. Our findings indicate that the replacement of H(2)O by D(2)O remarkably decreases the solubilities of the less soluble carbohydrates, such as maltose, raffinose and α-cyclodextrin. On the other hand, the more soluble saccharides, glucose, xylose, and sucrose, are practically insensitive to the H/D replacement in water. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Solubility of hydrogen isotopes in liquid LiPb

    International Nuclear Information System (INIS)

    Konishi, S.; Yamamoto, Y.; Noborio, K.; Calderoni, P.; Merrill, B.

    2014-01-01

    This research was performed mainly in the first half of the task 1-2 of TITAN project to investigate the interaction between hydrogen isotopes and liquid LiPb. Solubility of hydrogen in liquid LiPb was measured under a static condition. Kyoto University provided the first experimental apparatus shipped to Idaho, and Kyushu University succeeded the experiment and further improved. Obtained solubility generally agreed with some previous reports, but varied orders of magnitudes suggesting influence of impurity or other chemical processes. (author)

  16. Instant and supersaturated dissolution of naproxen and sesamin (poorly water-soluble drugs and supplements) nanoparticles prepared by continuous expansion of liquid carbon dioxide solution through long dielectric nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Arita, Toshihiko, E-mail: tarita@tagen.tohoku.ac.jp [Tohoku University, Institute of Multidisciplinary Research for Advanced Materials (Japan); Manabe, Noriyoshi [Tohoku University, Graduate School of Engineering (Japan); Nakahara, Koichi [Suntory Bussiness Expert Limited, Frontier Center for Value Creation (Japan)

    2012-11-15

    Nanoparticles (NPs) of naproxen (a nonsteroidal anti-inflammatory drug, BCS Class 2) and sesamin (a poorly water-soluble lignan) were investigated. By applying a newly developed rapid expansion system of liquid carbon dioxide solutions equipped with a dielectric nozzle, well-separated and fine both naproxen NPs (averaged particle size (APS) = 46.9 nm) and sesamin NPs (APS = 60.2 nm) were obtained without heating, surfactants, and co-solvents. Obtained naproxen and sesamin NPs had large surface/weight ratio, therefore, they showed instant dissolution to water until about ten percent higher than the saturated concentrations. In addition, the technique developed in the study has big advantage on producing especially drug NPs because the NPs produced by the method never includes neither poisonous additives (especially co-solvents and detergents) nor thermally denatured compounds.

  17. Radiculography with water-soluble contraste medium

    International Nuclear Information System (INIS)

    Araujo Pinheiro, R.S. de

    1987-01-01

    The etiologic diagnosis of the lumbar pain is discussed. The radiculography with water-soluble contrast medium is used and 250 cases are studied. Some practical criteria of indication executation and interpretation of the examination are reported. (M.A.C.) [pt

  18. Solubilities of hydrogen and methane in coal liquids

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ho-mu; Sebastian, H M; Simnick, J J; Chao, Kwang Chu

    1981-04-01

    The solubilities of hydrogen and methane in Exxon Donor Solvent (EDS) and Solvent Refined Coal II (SRC-II) coal liquids are determined at 190 and 270 C and pressures to 250 atm. Two narrow boiling distillate cuts from EDS and three from SRC-II are studied.

  19. Solubility data and modeling for sugar alcohols in ionic liquids

    International Nuclear Information System (INIS)

    Okuniewski, Marcin; Ramjugernath, Deresh; Naidoo, Paramespri; Domańska, Urszula

    2014-01-01

    Highlights: • Solubility of D-sorbitol and xylitol in six ILs. • The (liquid + liquid) phase equilibrium of (SA + IL) with UCST. • Interesting properties of [BMIM][TDI] IL. • The correlation with NRTL model. - Abstract: Ionic liquids (ILs) are novel media characterized by strong interactions with different organic substances which leads to a wide spectrum of applications involving extraction. Ionic liquids have been used as a solvent for sugar alcohols, sugars and hydrates. This work demonstrates the experimental and theoretical study of (liquid + liquid) phase equilibria for two sugar alcohols, D-sorbitol and xylitol in a few ILs based on different cations and anions (namely, 1-ethyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide [EMPIP][NTf 2 ], 1-hexyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide [HMPIP][NTf 2 ], N-hexylquinolinium bis(trifluoromethylsulfonyl)imide [HQuin][NTf 2 ], N-hexylisoquinolinium bis(trifluoromethylsulfonyl)imide [HiQuin][NTf 2 ], 1-butyl-1-methylimidazolium 4,5-dicyano-2-(trifluoromethyl)-imidazolide [BMIM][TDI] and 1-(cyanomethyl)-3-methylimidazolium 4,5-dicyano-2-(trifluoromethyl)-imidazolide [CCNMIM][TDI]). This study was conducted to assess the applicability of the studied ILs for dissolution of these biomass-related materials. (Liquid + liquid) phase equilibrium diagrams (LLE) in binary systems (sugar alcohol + ionic liquid) were measured using the dynamic technique. The influence of the chemical structure of both the ionic liquids and sugar alcohols were established and is discussed

  20. Solubility study of Tc(IV) in a granitic water

    International Nuclear Information System (INIS)

    Liu, D.J.; Yao, J.; Wang, B.; Bruggeman, C.; Maes, N.

    2007-01-01

    The deep geological disposal of the high level radioactive wastes is expected to be a safe disposal method in most countries. The long-lived fission product 99 Tc is present in large quantities in nuclear wastes and its chemical behavior in aqueous solution is of considerable interest. Under oxidizing conditions technetium exists as the anionic species TcO 4 - whereas under the reducing conditions, expected to exist in a deep geological repository, it is generally predicted that technetium will be present as TcO 2 .nH 2 O. Hence, the mobility of Tc(IV) in reducing groundwater may be limited by the solubility of TcO 2 .nH 2 O under these conditions. Due to this fact it is important to investigate the solubility of TcO 2 .nH 2 O. The solubility determines the release of radionuclides from waste form and is used as a source term in radionuclide migration analysis in performance assessment of radioactive waste repository. Technetium(IV) was prepared by reduction of a technetate solution with Sn 2+ . The solubility of Tc(IV) has been determined in simulated groundwater and redistilled water under aerobic and anaerobic conditions. The effects of pH and CO 3 2- concentration of solution on solubility of Tc(IV) were studied. The concentration of total technetium and Tc(IV) species in the solutions were periodically determined by separating the oxidized and reduced technetium species using a solvent extraction procedure and counting the beta activity of the 99 Tc with a liquid scintillation counter. The experimental results show that the rate of oxidation of Tc(IV) in simulated groundwater and redistilled water is about (1.49 ∝ 1.86) x 10 -9 mol L -1 d -1 under aerobic conditions, while no Tc(IV) oxidation was detected in simulated groundwater and redistilled water under anaerobic conditions. Under aerobic or anaerobic conditions the solubility of Tc(IV) in simulated groundwater and redistilled water is equal on the whole after centrifugation or ultrafiltration. The

  1. Water: The Strangest Liquid

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Anders

    2009-02-24

    Water, H2O, is familiar to everyone - it shapes our bodies and our planet. But despite its abundance, water has remained a mystery, exhibiting many strange properties that are still not understood. Why does the liquid have an unusually large capacity to store heat? And why is it denser than ice? Now, using the intense X-ray beams from particle accelerators, investigations into water are leading to fundamental discoveries about the structure and arrangement of water molecules. This lecture will elucidate the many mysteries of water and discuss current studies that are revolutionizing the way we see and understand one of the most fundamental substances of life.

  2. Biochemical synthesis of water soluble conducting polymers

    Science.gov (United States)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-05-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  3. Biochemical synthesis of water soluble conducting polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Ferdinando F., E-mail: Ferdinando-Bruno@uml.edu [US Army Natick Soldier Research, Development and Engineering Center, Natick, MA 01760 (United States); Bernabei, Manuele [ITAF, Test Flight Centre, Chemistry Dept. Pratica di Mare AFB, 00071 Pomezia (Rome), Italy (UE) (Italy)

    2016-05-18

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  4. Biochemical synthesis of water soluble conducting polymers

    International Nuclear Information System (INIS)

    Bruno, Ferdinando F.; Bernabei, Manuele

    2016-01-01

    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  5. The solubility of carbon in low-nitrogen liquid lithium

    International Nuclear Information System (INIS)

    Yonco, R.M.; Homa, M.I.

    1986-01-01

    The solubility of carbon in liquid lithium containing 0 C and compared with the solubility in lithium containing proportional 2600 wppm nitrogen in that same temperature range. A direct sampling method was employed in which filtered samples of the saturated solution were taken at randomly selected temperatures. The entire sample was analyzed for carbon by the acetylene evolution method. The analytical method was examined critically and it was found that (1) all of the carbon in solution, including carbon introduced as lithium cyanamide is detected and (2) ethylene and ethane must also be measured and included with the acetylene to get complete recovery of the carbon content of the sample. The solubility of carbon in low-nitrogen lithium can be expressed by the equations ln S=6.731-8617T -1 and log Ssup(*)=7.459-3740T -1 , where S is the mole percent Li 2 C 2 and Ssup(*) is in weight parts per million carbon. The presence of proportional 2600 wppm nitrogen does not affect the solubility of carbon in lithium at temperatures above proportional 350 0 C, but at lower temperatures it increased the solubility by as much as an order of magnitude compared to the solubility in low-nitrogen lithium. (orig.)

  6. Water Soluble Polymers for Pharmaceutical Applications

    OpenAIRE

    Veeran Gowda Kadajji; Guru V. Betageri

    2011-01-01

    Advances in polymer science have led to the development of novel drug delivery systems. Some polymers are obtained from natural resources and then chemically modified for various applications, while others are chemically synthesized and used. A large number of natural and synthetic polymers are available. In the present paper, only water soluble polymers are described. They have been explained in two categories (1) synthetic and (2) natural. Drug polymer conjugates, block copolymers, hydrogel...

  7. Ternary (liquid + liquid) equilibria of {bis(trifluoromethylsulfonyl)-amide based ionic liquids + butan-1-ol + water}

    International Nuclear Information System (INIS)

    Marciniak, Andrzej; Wlazło, Michał; Gawkowska, Joanna

    2016-01-01

    Highlights: • Ternary (liquid + liquid) equilibria for 3 ionic liquid + butanol + water systems. • The influence of ionic liquid structure on phase diagrams is discussed. • Influence of IL structure on S and β for butanol/water separation is discussed. - Abstract: Ternary (liquid + liquid) phase equilibria for 3 systems containing bis(trifluoromethylsulfonyl)-amide ionic liquids (1-buthyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)-amide, 1-(2-methoxyethyl)-1-methylpiperidinium bis(trifluoromethylsulfonyl)-amide, {1-(2-methoxyethyl)-1-methylpyrrolidinium bis(trifluorylsulfonyl)-amide) + butan-1-ol + water} have been determined at T = 298.15 K. The selectivity and solute distribution ratio were calculated for investigated systems and compared with literature data for other systems containing ionic liquids. In each system total solubility of butan-1-ol and low solubility of water in the ionic liquid is observed. The experimental results have been correlated using NRTL model. The influence of the structure of ionic liquid on phase equilibria, selectivity and solute distribution ratio is shortly discussed.

  8. Speciation of water soluble iron in size segregated airborne particulate matter using LED based liquid waveguide with a novel dispersive absorption spectroscopic measurement technique

    International Nuclear Information System (INIS)

    Chan, K.L.; Jiang, S.Y.N.; Ning, Z.

    2016-01-01

    In this study, we present the development and evaluation of a dispersive absorption spectroscopic technique for trace level soluble ferrous detection. The technique makes use of the broadband absorption spectra of the ferrous-ferrozine complex with a novel spectral fitting algorithm to determine soluble ferrous concentrations in samples and achieves much improved measurement precision compared to conventional methods. The developed method was evaluated by both model simulations and experimental investigations. The results demonstrated the robustness of the method against the spectral fluctuation, wavelength drift and electronic noise, while achieving excellent linearity (R 2  > 0.999) and low detection limit (0.06 μg L −1 ) for soluble ferrous detection. The developed method was also used for the speciation of soluble iron in size segregated atmospheric aerosols. The measurement was carried out during Spring and Summer in typical urban environment in Hong Kong. The measured total iron concentrations are in good agreement compared to conventional Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES) measurements. Investigation on ambient particulate matter samples shows the size dependent characteristic of iron speciation in the atmosphere with a more active role of fine particles in transforming between ferrous and ferric. The method demonstrated in this study provides a cost and time effective approach for the speciation of iron in ambient aerosols. - Highlights: • Dispersive absorption spectroscopic technique for trace level ferrous detection. • The spectral fitting retrieval improved the measurement precision and stability. • Extremely low detection limit was achieved for aqueous ferrous measurement. • Iron in size segregated particulate matters shows seasonal characteristic. • More active role of iron was found in fine particles compared to coarse particles.

  9. Speciation of water soluble iron in size segregated airborne particulate matter using LED based liquid waveguide with a novel dispersive absorption spectroscopic measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.L. [Meteorological Institute, Ludwig Maximilian University of Munich, Munich (Germany); School of Energy and Environment, City University of Hong Kong (Hong Kong); Jiang, S.Y.N. [School of Energy and Environment, City University of Hong Kong (Hong Kong); Ning, Z., E-mail: zhining@cityu.edu.hk [School of Energy and Environment, City University of Hong Kong (Hong Kong); Guy Carpenter Climate Change Centre, City University of Hong Kong (Hong Kong)

    2016-03-31

    In this study, we present the development and evaluation of a dispersive absorption spectroscopic technique for trace level soluble ferrous detection. The technique makes use of the broadband absorption spectra of the ferrous-ferrozine complex with a novel spectral fitting algorithm to determine soluble ferrous concentrations in samples and achieves much improved measurement precision compared to conventional methods. The developed method was evaluated by both model simulations and experimental investigations. The results demonstrated the robustness of the method against the spectral fluctuation, wavelength drift and electronic noise, while achieving excellent linearity (R{sup 2} > 0.999) and low detection limit (0.06 μg L{sup −1}) for soluble ferrous detection. The developed method was also used for the speciation of soluble iron in size segregated atmospheric aerosols. The measurement was carried out during Spring and Summer in typical urban environment in Hong Kong. The measured total iron concentrations are in good agreement compared to conventional Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES) measurements. Investigation on ambient particulate matter samples shows the size dependent characteristic of iron speciation in the atmosphere with a more active role of fine particles in transforming between ferrous and ferric. The method demonstrated in this study provides a cost and time effective approach for the speciation of iron in ambient aerosols. - Highlights: • Dispersive absorption spectroscopic technique for trace level ferrous detection. • The spectral fitting retrieval improved the measurement precision and stability. • Extremely low detection limit was achieved for aqueous ferrous measurement. • Iron in size segregated particulate matters shows seasonal characteristic. • More active role of iron was found in fine particles compared to coarse particles.

  10. Ideal gas solubilities and solubility selectivities in a binary mixture of room-temperature ionic liquids.

    Science.gov (United States)

    Finotello, Alexia; Bara, Jason E; Narayan, Suguna; Camper, Dean; Noble, Richard D

    2008-02-28

    This study focuses on the solubility behaviors of CO2, CH4, and N2 gases in binary mixtures of imidazolium-based room-temperature ionic liquids (RTILs) using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][Tf2N]) and 1-ethyl-3-methylimidazolium tetrafluoroborate ([C2mim][BF4]) at 40 degrees C and low pressures (approximately 1 atm). The mixtures tested were 0, 25, 50, 75, 90, 95, and 100 mol % [C2mim][BF4] in [C2mim][Tf2N]. Results show that regular solution theory (RST) can be used to describe the gas solubility and selectivity behaviors in RTIL mixtures using an average mixture solubility parameter or an average measured mixture molar volume. Interestingly, the solubility selectivity, defined as the ratio of gas mole fractions in the RTIL mixture, of CO2 with N2 or CH4 in pure [C2mim][BF4] can be enhanced by adding 5 mol % [C2mim][Tf2N].

  11. Solubility of the Proteinogenic α-Amino Acids in Water, Ethanol, and Ethanol–Water Mixtures

    Science.gov (United States)

    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, l-arginine, l-cysteine, and l-lysine in water and ethanol mixtures and the solubility of l-alanine, l-proline, l-arginine, l-cysteine, l-lysine, l-asparagine, l-glutamine, l-histidine, and l-leucine in pure ethanol systems were measured and are published here for the first time. The impact on the solubility of amino acids that can convert in solution, l-glutamic acid and l-cysteine, was studied. At lower concentrations, only the ninhydrin method and the ultraperfomance liquid chromatography (UPLC) method yield reliable results. In the case of α-amino acids that convert in solution, only the UPLC method was able to discern between the different α-amino acids and yields reliable results. Our results demonstrate that α-amino acids with similar physical structures have similar changes in solubility in mixed water/ethanol mixtures. The solubility of l-tryptophan increased at moderate ethanol concentrations. PMID:29545650

  12. 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

  13. Solubility study of Tc(Ⅳ) in a granitic water

    International Nuclear Information System (INIS)

    Liu Dejun; Yao Jun; Wang Bo

    2008-01-01

    The deep geological disposal of the high level radioactive wastes is expected to be a safe disposal method in most countries. The long-lived fission product 99 Tc is present in large quantities in nuclear wastes and its chemical behavior in aqueous solution is of considerable interest. Under oxidizing conditions technetium exists as the anionic species TcO 4 - whereas under the reducing conditions, expected to exist in a deep geological repository, it is generally predicted that technetium will be present as TcO 2 -nH 2 O. Hence, the mobility of Tc(Ⅳ) in reducing groundwater may be limited by the solubility of TcO 2 ·nH 2 O under these conditions. Due to this fact it is important to investigate the solubility of TcO 2 ·nH 2 O. The solubility determines the release of radionuclides from waste form and is used as a source term in radionuclide migration analysis in performance assessment of radioactive waste repository. Technetium (Ⅳ) was prepared by reduction of a technetate solution with Sn 2+ . The solubility of Tc(Ⅳ) has been determined in simulated groundwater and redistilled water under aerobic and anaerobic conditions. The effects of pH and CO 3 2- concentration of solution on solubility of Tc(Ⅳ) were studied. The concentration of total technetium and Tc(Ⅳ) species in the solutions were periodically determined by separating the oxidized and reduced technetium species using a solvent extraction procedure and counting the beta activity of the 99 Tc with a liquid scintillation counter. The experimental results show that the rate of oxidation of Tc(Ⅳ) in simulated groundwater and redistilled water is about (1.49-1.86)x10 -9 mol·L -1 d -1 under aerobic conditions, while no Tc(Ⅳ) oxidation was detected in simulated groundwater and redistilled water under anaerobic conditions. Under aerobic or anaerobic conditions the solubility of Tc(Ⅳ) in simulated groundwater and redistilled water is equal on the whole after centrifugation or ultrafiltration. The

  14. Effects of polarity, hydrophobicity, and density of ionic liquids on cellulose solubility.

    Science.gov (United States)

    Abe, Mitsuru; Kuroda, Kosuke; Sato, Daiki; Kunimura, Haruhito; Ohno, Hiroyuki

    2015-12-28

    We have synthesised novel ionic liquids (ILs) to show both cellulose dissolution ability and LCST-type phase transition after mixing with water. To realise both polar and hydrophobic properties, tetraalkylphosphonium cations and a series of carboxylate anions were employed to assume hydrophobic and highly polar properties, respectively. Effects of their alkyl chain length on the water compatibility and cellulose solubility of the corresponding ILs were systematically examined. We succeeded in synthesising novel ILs which dissolve cellulose and separable with water at moderate temperature. Through the present study, we have clarified that not only polarity but also density of ILs is an important factor in designing the ILs for cellulose dissolution.

  15. Indomethacin solubility estimation in 1,4-dioxane + water mixtures by the extended hildebrand solubility approach

    Directory of Open Access Journals (Sweden)

    Miller A Ruidiaz

    2011-09-01

    Full Text Available Extended Hildebrand Solubility Approach (EHSA was successfully applied to evaluate the solubility of Indomethacin in 1,4-dioxane + water mixtures at 298.15 K. An acceptable correlation-performance of EHSA was found by using a regular polynomial model in order four of the W interaction parameter vs. solubility parameter of the mixtures (overall deviation was 8.9%. Although the mean deviation obtained was similar to that obtained directly by means of an empiric regression of the experimental solubility vs. mixtures solubility parameters, the advantages of EHSA are evident because it requires physicochemical properties easily available for drugs.

  16. Optimization of simultaneous ultrasonic-assisted extraction of water-soluble and fat-soluble characteristic constituents from Forsythiae Fructus Using response surface methodology and high-performance liquid chromatography.

    Science.gov (United States)

    Xia, Yong-Gang; Yang, Bing-You; Liang, Jun; Wang, Di; Yang, Qi; Kuang, Hai-Xue

    2014-07-01

    The compounds (+)-pinoresinol-β-glucoside (1) forsythiaside, (2) phillyrin (3) and phillygenin (4) were elucidated to be the characteristic constituents for quality control of Forsythiae Fructus extract by chromatographic fingerprint in 2010 edition of Chinese Pharmacopoeia due to their numerous important pharmacological actions. It is of great interest to extract these medicinally active constituents from Forsythiae Fructus simultaneously. In this study, a new ultrasound-assisted extraction (UAE) method was developed for the simultaneous extraction of biological components 1-4 in Forsythiae Fructus. The quantitative effects of extraction time, ratio of liquid to solid, extraction temperature, and methanol concentration on yield of these four important biological constituents from Forsythiae Fructus were investigated using response surface methodology with Box-Behnken design. The compounds 1-4 extracted by UAE were quantitative analysis by high-performance liquid chromatography-photodiode array detect (HPLC-PAD), and overall desirability (OD), the geometric mean of the contents of four major biological components, was used as a marker to evaluate the extraction efficiency. By solving the regression equation and analyzing 3-D plots, the optimum condition was at extraction temperature 70°C, time 60 min, ratio of liquid to solid 20, and methanol concentration 76.6%. Under these conditions, extraction yields of compounds 1-4 were 2.92 mg/g, 52.10 mg/g, 0.90 mg/g and 0.57 mg/g, respectively, which were in good agreement with the predicted OD values. In order to achieve a similar yield as UAE, soxhlet extraction required at least 6 h and maceration extraction required much longer time of 24 h. Established UAE method has been successfully applied to sample preparation for the quality control of Forsythiae Fructus. Additionally, a quadrupole time-of-flight mass spectrometry was applied to the structural confirmation of analytes from the complex matrices acquired by UAE

  17. Optimization of simultaneous ultrasonic-assisted extraction of water-soluble and fat-soluble characteristic constituents from Forsythiae Fructus Using response surface methodology and high-performance liquid chromatography

    Science.gov (United States)

    Xia, Yong-Gang; Yang, Bing-You; Liang, Jun; Wang, Di; Yang, Qi; Kuang, Hai-Xue

    2014-01-01

    Background: The compounds (+)-pinoresinol-β-glucoside (1) forsythiaside, (2) phillyrin (3) and phillygenin (4) were elucidated to be the characteristic constituents for quality control of Forsythiae Fructus extract by chromatographic fingerprint in 2010 edition of Chinese Pharmacopoeia due to their numerous important pharmacological actions. It is of great interest to extract these medicinally active constituents from Forsythiae Fructus simultaneously. Materials and Methods: In this study, a new ultrasound-assisted extraction (UAE) method was developed for the simultaneous extraction of biological components 1-4 in Forsythiae Fructus. The quantitative effects of extraction time, ratio of liquid to solid, extraction temperature, and methanol concentration on yield of these four important biological constituents from Forsythiae Fructus were investigated using response surface methodology with Box-Behnken design. The compounds 1-4 extracted by UAE were quantitative analysis by high-performance liquid chromatography-photodiode array detect (HPLC-PAD), and overall desirability (OD), the geometric mean of the contents of four major biological components, was used as a marker to evaluate the extraction efficiency. Results: By solving the regression equation and analyzing 3-D plots, the optimum condition was at extraction temperature 70°C, time 60 min, ratio of liquid to solid 20, and methanol concentration 76.6%. Under these conditions, extraction yields of compounds 1-4 were 2.92 mg/g, 52.10 mg/g, 0.90 mg/g and 0.57 mg/g, respectively, which were in good agreement with the predicted OD values. In order to achieve a similar yield as UAE, soxhlet extraction required at least 6 h and maceration extraction required much longer time of 24 h. Established UAE method has been successfully applied to sample preparation for the quality control of Forsythiae Fructus. Additionally, a quadrupole time-of-flight mass spectrometry was applied to the structural confirmation of analytes

  18. On the solubility of plutonium in water

    International Nuclear Information System (INIS)

    Naegele, G.

    1977-12-01

    In a theoretical study, the chemical equilibrium state of saturated Pu solutions in water was determined and the effect of the addition of EDTA on the solubility of Pu estimated. Concentrations of Plutonium in true solution in the range of grams/litre seem to be achievable, at least in principle. The amount of EDTA necessary is not larger than the total amount of Pu. It is however questionable, specially after taking into account all possible effects of reaction kinetics, whether such high concentrations can be achieved at all under normal environmental conditions. Only experiments under real world conditions can give an answer to this question. (orig./HK) 891 HK 892 AP [de

  19. Visible-light photoactive Ag–AgBr/α-Ag3VO4 nanostructures prepared in a water-soluble ionic liquid for degradation of wastewater

    Directory of Open Access Journals (Sweden)

    Mohsen Padervand

    2016-03-01

    Full Text Available Abstract Ag–AgBr/α-Ag3VO4 photocatalysts, prepared by an ionic liquid-assisted precipitation method, were used as an efficient visible light-driven photocatalytic system for removal of wastewater and pathogenic bacteria from the aqueous medium. X-ray diffraction powder, diffuse reflectance spectroscopy, Fourier transform infrared, scanning electron microscopy, and nitrogen adsorption–desorption isotherm (BET analysis methods were used to characterize the nanostructures. Photodegradation mechanism was investigated and the results showed that the prepared samples were too efficient for the degradation of Acid Blue 92 (AB92 azo dye, and E. coli cells under visible light. The photogenerated electron–hole pairs reacted with the species in the solution and produced super active radicals such as $${\\rm{O}}{{\\rm{H}}^ \\cdot }$$ O H · , $${\\rm{H}}{{\\rm{O}}^ \\cdot }_{\\rm{2}}$$ H O · 2 , and $${{\\rm{O}}^{ \\cdot - }}_{\\rm{2}}$$ O · - 2 which are responsible for the degradation of the environmental pollutions. TEM images were used to clarify the antibacterial activity of the products. Finally, as a practical application of the prepared photocatalysts, their ability evaluated for degradation of a real wastewater sample which was provided from the textile industries.

  20. Analysis of the monosaccharide composition of water-soluble polysaccharides from Sargassum fusiforme by high performance liquid chromatography/electrospray ionisation mass spectrometry.

    Science.gov (United States)

    Wu, Xiaodan; Jiang, Wei; Lu, Jiajia; Yu, Ying; Wu, Bin

    2014-02-15

    Sargassum fusiforme (hijiki) is the well-known edible algae, whose polysaccharides have been proved to possess interesting bioactivities like antitumor, antioxidant, antimicrobial and immunomodulatory activities. A facile and sensitive method based on high-performance liquid chromatography method of pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) coupled with electrospray ionisation mass spectrometry (HPLC/ESI-MS) has been established for the analysis of the monosaccharide composition of polysaccharides in S. fusiforme. Monosaccharides have been converted into PMP-labelled derivatives with aqueous ammonia as a catalyst at 70 °C for 30 min. The optimisation of the pre-column derivatization process was studied. The LODs of the monosaccharides were in the range from 0.01 to 0.02 nmol. PMP-labelled mixture of monosaccharides has been well separated by a reverse-phase HPLC and detected by on-line ESI-MS method under optimised conditions. The mobile phase of elution system was chosen as acetonitrile (solvent A) and 20mM aqueous ammonium acetate (solvent B) (pH 3.0) with Zorbax XDB-C18 column at 30 °C for the separation of the monosaccharide derivatives. Identification of the monosaccharides composition was carried out by analysis with mass spectral behaviour and chromatography characteristics of 1-phenyl-3-methyl-5-pyrazolone (PMP) labelled monosaccharides. All PMP-labelled derivatives display high chemical stabilities, whose regular MS fragmentation is specific for reducing labelled sugars. The result showed that the S. fusiforme polysaccharide consisted of mannose, glucose, galactose, xylose, fucose and glucuronic acid or galacturonic acid, or both uronic acids. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. 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.

  2. Interlaboratory validation of small-scale solubility and dissolution measurements of poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Andersson, Sara B. E.; Alvebratt, Caroline; Bevernage, Jan

    2016-01-01

    The purpose of this study was to investigate the interlaboratory variability in determination of apparent solubility (Sapp) and intrinsic dissolution rate (IDR) using a miniaturized dissolution instrument. Three poorly water-soluble compounds were selected as reference compounds and measured at m...

  3. Water-soluble resorcin[4]arene based cavitands

    NARCIS (Netherlands)

    Grote gansey, M.H.B.; Grote Gansey, Marcel H.B.; Bakker, Frank K.G.; Feiters, Martinus C.; Geurts, Hubertus P.M.; Verboom, Willem; Reinhoudt, David

    1998-01-01

    Water-soluble resorcin[4]arene based cavitands were obtained in good yields by reaction of bromomethylcavitands with pyridine. Their solubility was determined by conductometry. The behaviour in water depends on the alkyl chain length; the methylcavitand does not aggregate, whereas the pentyl- and

  4. Leaching behavior of water-soluble carbohydrates from almond hulls

    Science.gov (United States)

    Over 58% of the dry matter content of the hulls from the commercial almond (Prunus dulcis (Miller) D.A. Webb) is soluble in warm water (50-70°C) extraction. The water-soluble extractables include useful amounts of fermentable sugars (glucose, fructose, sucrose), sugar alcohols (inositol and sorbito...

  5. Uranium solubility and speciation in ground water

    International Nuclear Information System (INIS)

    Ollila, K.

    1985-04-01

    The purpose of this study has been to assess the solubility and possible species of uranium in groundwater at the disposal conditions of spent fuel. The effects of radiolysis and bentonite are considered. The assessment is based on the theoretical calculations found in the literature. The Finnish experimental results are included. The conservative estimate for uranium solubility under the oxidizing conditions caused by alpha radiolysis is based on the oxidation of uranium to the U(VI) state and formation of carbonate complex. For the groundwater with the typical carbonate content of 275 mg/l and the high carbonate content of 485 mg/l due to bentonite, the solubility values of 360 mg u/l and 950 mg U/l, are obtained, respectively. The experimental results predict considerably lower values, 0.5-20 mg U/l. The solubility of uranium under the undisturbed reducing conditions may be calculated based on the hydrolysis, carbonate complexation and redox reactions. The results vary considerably depending on the thermodynamic data used. The wide ranges of the most important groundwater parameters are seen in the solubility values. The experimental results show the same trends. As a conservative value for the solubility in reducing groundwater 50-500 μg U/l is estimated. (author)

  6. 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...

  7. Study of solubility of akaline earth metals in liquid iron and in alloys on its base

    International Nuclear Information System (INIS)

    Ageev, Yu.A.; Archugov, S.A.

    1985-01-01

    Solubility of magnesium, calcium, strontium and barium in liquid iron and its alloys with aluminium, silicon, nickel, chromium and carbon at 1600 deg C has been measured. Interaction parameters taking account of the effect of added elements on alkaline earth metal solubility in liquid iron have been estimated

  8. Solubility of corrosion products in high temperature water

    International Nuclear Information System (INIS)

    Srinivasan, M.P.; Narasimhan, S.V.

    1995-01-01

    A short review of solubility of corrosion products at high temperature in either neutral or alkaline water as encountered in BWR, PHWR and PWR primary coolant reactor circuits is presented in this report. Based on the available literature, various experimental techniques involved in the study of the solubility, theory for fitting the solubility data to the thermodynamic model and discussion of the published results with a scope for future work have been brought out. (author). 17 refs., 7 figs

  9. Water-soluble dietary fibers and cardiovascular disease.

    Science.gov (United States)

    Theuwissen, Elke; Mensink, Ronald P

    2008-05-23

    One well-established way to reduce the risk of developing cardiovascular disease (CVD) is to lower serum LDL cholesterol levels by reducing saturated fat intake. However, the importance of other dietary approaches, such as increasing the intake of water-soluble dietary fibers is increasingly recognized. Well-controlled intervention studies have now shown that four major water-soluble fiber types-beta-glucan, psyllium, pectin and guar gum-effectively lower serum LDL cholesterol concentrations, without affecting HDL cholesterol or triacylglycerol concentrations. It is estimated that for each additional gram of water-soluble fiber in the diet serum total and LDL cholesterol concentrations decrease by -0.028 mmol/L and -0.029 mmol/L, respectively. Despite large differences in molecular structure, no major differences existed between the different types of water-soluble fiber, suggesting a common underlying mechanism. In this respect, it is most likely that water-soluble fibers lower the (re)absorption of in particular bile acids. As a result hepatic conversion of cholesterol into bile acids increases, which will ultimately lead to increased LDL uptake by the liver. Additionally, epidemiological studies suggest that a diet high in water-soluble fiber is inversely associated with the risk of CVD. These findings underlie current dietary recommendations to increase water-soluble fiber intake.

  10. Solubility and physical properties of sugars in pressurized water

    International Nuclear Information System (INIS)

    Saldaña, Marleny D.A.; Alvarez, Víctor H.; Haldar, Anupam

    2012-01-01

    Highlights: ► Sugar solubility in pressurized water and density at high pressures were measured. ► Glucose solubility was higher than that of lactose as predicted by their σ-profiles. ► Sugar aqueous solubility decreased with an increase in pressure from 15 to 120 bar. ► Aqueous glucose molecular packing shows high sensitivity to pressure. ► The COSMO-SAC model qualitatively predicted the sugar solubility data. - Abstract: In this study, the solubility, density, and refractive index of glucose and lactose in water as a function of temperature were measured. For solubility of sugars in pressurized water, experimental data were obtained at pressures of (15 to 120) bar and temperatures of (373 to 433) K using a dynamic flow high pressure system. Density data for aqueous sugar solutions were obtained at pressures of (1 to 300) bar and temperatures of (298 to 343) K. The refractive index of aqueous sugar solutions was obtained at 293 K and atmospheric pressure. Activity coefficient models, Van Laar and the Conductor-like Screening Model-Segment Activity Coefficient (COSMO-SAC), were used to fit and predict the experimental solubility data, respectively. The results obtained showed that the solubility of both sugars in pressurized water increase with an increase in temperature. However, with the increase of pressure from 15 bar to 120 bar, the solubility of both sugars in pressurized water decreased. The Van Laar model fit the experimental aqueous solubility data with deviations lower than 13 and 53% for glucose and lactose, respectively. The COSMO-SAC model predicted qualitatively the aqueous solubility of these sugars.

  11. 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

  12. Study on REE bound water-soluble polysaccharides in plant

    International Nuclear Information System (INIS)

    Wang Yuqi; Guo Fanqing; Xu Lei; Chen Hongmin; Sun Jingxin; Cao Guoyin

    1999-01-01

    The binding of REE with water-soluble polysaccharides (PSs) in leaves of fern Dicranopteris Dichotoma (DD) has been studied by molecular activation analysis. The cold-water-soluble and hot-water-soluble PSs in leaves of DD were obtained by using biochemical separation techniques. The PSs of non-deproteinization and deproteinization, were separated on Sephadex G-200 gel permeation chromatography. The absorption curves of elution for the PSs were obtained by colorimetry, and the proteins were detected using Coomassic brilliant G-250. Eight REEs (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in these PSs were determined by instrumental neutron activation analysis. The results obtained show that the REEs are bound firmly with the water-soluble PSs in the plant. A measurement demonstrates that the PSs bound with REEs are mainly of smaller molecular weight (10,000 to 20,000 Dalton)

  13. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    NICO

    radiation balance.4,5 Major water-soluble inorganic ions are associated with atmospheric ... molecular weight carboxylic acids in aerosol samples collected from a rural ... include biomass burning, agriculture, livestock and soil dust. Tropical ...

  14. Effect of water deficit stress on proline contents, soluble sugars ...

    African Journals Online (AJOL)

    Effect of water deficit stress on proline contents, soluble sugars, chlorophyll and grain yield of sunflower ... Journal Home > Vol 11, No 1 (2012) > ... The objective of the present work was to determine the mechanisms of tolerance of four ...

  15. Solubility and degradation of paracetamol in subcritical water

    Directory of Open Access Journals (Sweden)

    Emire Zuhal

    2017-01-01

    Full Text Available In this study, solubility and degradation of paracetamol were examined using subcritical water. Effect of temperature and static time was investigated during solubility process in subcritical water at constant pressure (50 bar. Experimental results show that temperature and static time have crucial effect on the degradation and solubility rates. Maximum mole fraction for solubility of paracetamol was obtained at 403 K as (14.68 ± 0.74×103. Approximation model for solubility of paracetamol was proposed. O2 and H2O2 were used in degradation process of paracetamol. Maximum degradation rate was found as 68.66 ± 1.05 and 100 ± 0.00 % using O2 and H2O2, respectively.

  16. Water quality for liquid wastes

    International Nuclear Information System (INIS)

    Mizuniwa, Fumio; Maekoya, Chiaki; Iwasaki, Hitoshi; Yano, Hiroaki; Watahiki, Kazuo.

    1985-01-01

    Purpose: To facilitate the automation of the operation for a liquid wastes processing system by enabling continuous analysis for the main ingredients in the liquid wastes accurately and rapidly. Constitution: The water quality monitor comprises a sampling pipeway system for taking out sample water for the analysis of liquid wastes from a pipeway introducing liquid wastes to the liquid wastes concentrator, a filter for removing suspended matters in the sample water and absorption photometer as a water quality analyzer. A portion of the liquid wastes is passed through the suspended matter filter by a feedpump. In this case, sulfate ions and chloride ions in the sample are retained in the upper portion of a separation color and, subsequently, the respective ingredients are separated and leached out by eluting solution. Since the leached out ingredients form ferric ions and yellow complexes respectively, their concentrations can be detected by the spectrum photometer. Accordingly, concentration for the sodium sulfate and sodium chloride in the liquid wastes can be analyzed rapidly, accurately and repeatedly by which the water quality can be determined rapidly and accurately. (Yoshino, Y.)

  17. Characterization of Gasolines, Diesel Fuels and Their Water Soluble Fractions

    Science.gov (United States)

    1983-09-01

    Hutchinson, et al.,1979 ) with the marine algae, Chlorella vulgaris and Chlamydomonas angulosa, suggests that the toxicity of hydrocarbons is a...water-soluble petroleum components on the growth of Chlorella vulgaris Beijernck. Environ. Poll. 9: 157. Morrow, J.E., et al. 1975. Effects of some...P.B., and T.C. Hutchison. 1975. The effects of water-soluble petroleum components on the growth of Chlorella vulqaris Beijerinck. Environ. Poll. 9

  18. CO2 Solubilities in Amide-based Brφnsted Acidic Ionic Liquids

    International Nuclear Information System (INIS)

    Palgunadi, Jelliarko; Im, Jin Kyu; Kang, Je Eun; Kim, Hoon Sik; Cheong, Min Serk

    2010-01-01

    A distinguished class of hydrophobic ionic liquids bearing a Brφnsted acidic character derived from amide-like compounds were prepared by a neutralization reaction of N,N-diethylformamide, N,N-dibutylformamide, 1-formylpiperidine, and ε-caprolactam with trifluoroacetic acid and physical absorptions of CO 2 in these ionic liquids were demonstrated and evaluated. CO 2 solubilities in these ionic liquids were influenced by the molecular structure of the cation and were apparently increased with the molar volume. Comparison based on a volume unit reveals that CO 2 solubilities in these liquids are relatively higher than those in imidazolium-based ionic liquids. Henry's coefficients calculated from low-pressure solubility tests at 313 to 333 K were used to derive the thermodynamics quantities. Enthalpy and entropy of solvation may share equal contributions in solubility

  19. Thermodynamic analysis and evaluation of the nitrogen solubility in liquid Nb and Fe-Nb alloys

    International Nuclear Information System (INIS)

    Qiu Caian

    1994-01-01

    Experimental information on the nitrogen solubility in liquid Nb and Fe-Nb alloys has been critically analysed and then utilized to evaluate the thermodynamic properties of the Nb-N and Fe-Nb-N liquid phases on the basis of thermodynamic models of Gibbs energy. A thermodynamic description of the Fe-Nb-N liquid phase was obtained, which has been used to calculate the N solubility in comparison with experimental results. The effect of an addition of Nb on the temperature dependence of the N solubility in liquid Fe has been examined by comparing with the effect of the Cr and V additions. It has been shown that the N solubility in liquid Nb and Fe-Nb alloys under various conditions is well described by the present calculation. (orig.)

  20. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate.

    Science.gov (United States)

    Yousaf, Abid Mehmood; Mustapha, Omer; Kim, Dong Wuk; Kim, Dong Shik; Kim, Kyeong Soo; Jin, Sung Giu; Yong, Chul Soon; Youn, Yu Seok; Oh, Yu-Kyoung; Kim, Jong Oh; Choi, Han-Gon

    2016-01-01

    The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate. Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP) and Labrafil(®) M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion. All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1:4:0.5 resulted in a particle size of water-soluble fenofibrate.

  1. Shallow Water Tuned Liquid Dampers

    DEFF Research Database (Denmark)

    Krabbenhøft, Jørgen

    that for realistic roughness parameters the bottom friction has very limited effect on the liquid sloshing behavior and can be neglected. Herby the postulate is verified. Based on the mathematical model three dimensionless parameters are derived showing that the response of the damper depends solely on ratio......The use of sloshing liquid as a passive means of suppressing the rolling motion of ships was proposed already in the late 19th century. Some hundred years later the use of liquid sloshing devices, often termed Tuned Liquid Dampers (TLD), began to find use in the civil engineering community....... The TLDs studied in this thesis essentially consist of a rectangular container partially filled with liquid in the form of plain tap water. The frequency of the liquid sloshing motion, which is adjusted by varying the length of the tank and the depth of the wa- ter, is tuned to the structural frequency...

  2. [Determination of equilibrium solubility and n-octanol/water partition coefficient of pulchinenosiden D by HPLC].

    Science.gov (United States)

    Rao, Xiao-Yong; Yin, Shan; Zhang, Guo-Song; Luo, Xiao-Jian; Jian, Hui; Feng, Yu-Lin; Yang, Shi-Lin

    2014-05-01

    To determine the equilibrium solubility of pulchinenosiden D in different solvents and its n-octanol/water partition coefficients. Combining shaking flask method and high performance liquid chromatography (HPLC) to detect the n-octanol/water partition coefficients of pulchinenosiden D, the equilibrium solubility of pulchinenosiden D in six organic solvents and different pH buffer solution were determined by HPLC analysis. n-Octanol/water partition coefficients of pulchinenosiden D in different pH were greater than zero, the equilibrium solubility of pulchinenosiden D was increased with increase the pH of the buffer solution. The maximum equilibrium solubility of pulchinenosiden D was 255.89 g x L(-1) in methanol, and minimum equilibrium solubility of pulchinenosiden D was 0.20 g x L(-1) in acetonitrile. Under gastrointestinal physiological conditions, pulchinenosiden D exists in molecular state and it has good absorption but poor water-solubility, so increasing the dissolution rate of pulchinenosiden D may enhance its bioavailability.

  3. Mechanisms for oral absorption of poorly water-soluble compounds

    DEFF Research Database (Denmark)

    Lind, Marianne Ladegaard

    Abstract A large part of the new drug candidates discovered by the pharmaceutical industry have poor solubility in aqueous media. The preferred route of drug administration is the oral route, but for these poorly water-soluble drug candidates the oral bioavailability can be low and variable. Often......, phospholipids) and exogenous surfactants used in pharmaceutical formulations on the oral absorption of poorly water-soluble drug substances. Three different models were used for this purpose. The first model was the in vitro Caco-2 cell model. Simulated intestinal fluids which did not decrease cellular...... products are important for the solubilization of poorly water-soluble drug substances and thus absorption. The second model used was the lipoprotein secreting Caco-2 cell model, which was used to simulate intestinal lymphatic transport in vitro. Various simulated intestinal fluids were composed...

  4. Binary, ternary and quaternary liquid-liquid equilibria in 1-butanol, oleic acid, water and n-heptane mixtures

    NARCIS (Netherlands)

    Winkelman, J. G. M.; Kraai, G. N.; Heeres, H. J.

    2009-01-01

    This work reports on liquid-liquid equilibria in the system 1-butanol, oleic acid, water and n-heptane used for biphasic, lipase catalysed esterifications. The literature was studied on the mutual solubility in binary systems of water and each of the organic components. Experimental results were

  5. Electrically excited liquid water

    NARCIS (Netherlands)

    Wexler, A.D.

    2016-01-01

    Water is essential to a healthy and secure world. Developing new technologies which can take full advantage of the unique attributes of water is important for meeting the ever increasing global demand while reducing the production footprint. Water exhibits unexpected departures in more than 70

  6. Solubilities of some gases in four immidazolium-based ionic liquids

    International Nuclear Information System (INIS)

    Afzal, Waheed; Liu, Xiangyang; Prausnitz, John M.

    2013-01-01

    Graphical abstract: Experimental apparatus based on the synthetic-volumetric method for measuring solubilities of gases in liquids. Highlights: • We constructed an apparatus for measuring solubilities of sparingly-soluble gases. • We measured solubilities of five gases in four immidazolium-based ionic liquids. • We calculated Henry’s constants for gases in the ionic liquids studied in this work. -- Abstract: The synthetic-volumetric method is used for rapidly measuring solubilities of sparingly-soluble gases in monoethylene glycol and in four ionic liquids. Known molar quantities of solute and solvent are charged into an equilibrium vessel. Measured quantities at equilibrium include: temperature, pressure, quantities of fluids, and volumes of the gas and liquid phases in the equilibrium vessel. These measurements enable calculation of equilibrium compositions using material balances. No sampling or chemical analyses are required. Solubilities are reported for carbon dioxide, krypton, oxygen, and hydrogen in monoethylene glycol, l-n-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4], l-n-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [EMIM][Tf 2 N], or 1-ethyl-3-methylimidazolium acetate [EMIM][AC]. Solubilities were measured over the temperature range (298 to 355) K and for pressures up to about 7 MPa using two different pieces of equipment, both based on the volumetric method: a low-pressure glass apparatus and a high-pressure stainless-steel apparatus. Special emphasis is given to experimental reliability to assure consistent data

  7. Solubility investigation of ether and ester essential oils in water using spectrometry and GC/MS

    Directory of Open Access Journals (Sweden)

    B. Khodabandeloo

    2017-11-01

    Full Text Available Background and objectives: Essential oils (volatiles are aromatic oily liquids prepared from different parts of plants and demonstrate various therapeutic and cosmetic properties. The dissolution of essential oils are not desirable in water, therefore the aim of this research was evaluation and selection the best co-solvents for increasing their solubility and bio availability. Methods:The solubility of six  plants essential oils were investigated in presence of propylene glycol (PG, polyethylene glycol 300 (PEG, glycerin and ethanol as solvent and tween 80 or lecithin as co-solvent by observation and spectrophotometric assay. Chemical composition of the essential oils and supersaturated 50% ethanol (SSE and 50% PG or PEG (SSP solutions were analyzed by GC/MS, too. Results: Ester (Lavandula dentata, Heracleum persicum and, Elettaria cardamomum essential oils showed the best solubility in ethanol and PG, respectively. Ether (Foeniculum vulgare, Pimpinella anisum and Petroselinum crispum essential oils had the best solubility in ethanol and PEG, respectively. In ester class, mixture of ethanol/water was the best solvent according to solubility and total amounts of major compounds of the essential oils. In ether class, all samples had better solubility in mixtures of ethanol/water than PEG, but the amounts of total phenols or ethers in SSP of some samples were higher than SSE. Therefore selecting the best solvent for these class need more experiments. Conclusion: Selecting the solvent for essential oils changes their chemical composition; therefore the best solvent was different for various purposes.

  8. Wax encapsulation of water-soluble compounds for application in foods.

    Science.gov (United States)

    Mellema, M; Van Benthum, W A J; Boer, B; Von Harras, J; Visser, A

    2006-11-01

    Water-soluble ingredients have been successfully encapsulated in wax using two preparation techniques. The first technique ('solid preparation') leads to relatively large wax particles. The second technique ('liquid preparation') leads to relatively small wax particles immersed in vegetable oil. On the first technique: stable encapsulation of water-soluble colourants (dissolved at low concentration in water) has been achieved making use of beeswax and PGPR. The leakage from the capsules, for instance of size 2 mm, is about 30% after 16 weeks storage in water at room temperature. To form such capsules a minimum wax mass of 40% relative to the total mass is needed. High amounts of salt or acids at the inside water phase causes more leaking, probably because of the osmotic pressure difference. Osmotic matching of inner and outer phase can lead to a dramatic reduction in leakage. Fat capsules are less suitable to incorporate water soluble colourants. The reason for this could be a difference in crystal structure (fat is less ductile and more brittle). On the second technique: stable encapsulation of water-soluble colourants (encapsulated in solid wax particles) has been achieved making use of carnauba wax. The leakage from the capsules, for instance of size 250 mm, is about 40% after 1 weeks storage in water at room temperature.

  9. Solubility of carbon dioxide in the ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate

    NARCIS (Netherlands)

    Althuluth, M.A.M.; Mota Martinez, M.T.; Kroon, M.C.; Peters, C.J.

    2012-01-01

    Recently, the use of ionic liquids (ILs) for gas separation processes has attracted much attention because of the high solubility of different gaseous species in ILs. This contribution presents new experimental measurements of the carbon dioxide (CO2) solubility in the IL 1-ethyl-3 methylimidazolium

  10. The solubilities of benzene polycarboxylic acids in water

    International Nuclear Information System (INIS)

    Apelblat, Alexander; Manzurola, Emanuel; Abo Balal, Nazmia

    2006-01-01

    The solubilities in water of all benzene polycarboxylic acids are discussed, using data determined in this work (benzoic, terephthalic, trimellitic, trimesic, and pyromellitic acids) and available from the literature (benzoic, phthalic, isophthalic, terephthalic, hemimellitic, trimelitic, trimesic, mellophanic, prehnitic, pyromellitic, benzene-pentacarboxylic and mellitic acids). The apparent molar enthalpies of solution at the saturation point for these benzene polycarboxylic acids were determined from the temperature dependence of the solubilities

  11. Solubility of Hydrogen and Nitrogen in liquid cast iron during melting and mold filling

    OpenAIRE

    Diószegi, Attila; Elfsberg, Jessica; Diószegi, Zoltán

    2016-01-01

    Defect formation like gas- and shrinkage porosity at cast iron component production is related to the content of gaseous elements in the liquid metal. The present work investigate the solubility of hydrogen and nitrogen in liquid iron aimed for production of lamellar and compacted graphite cast iron. The used methods and instruments are a combination of commercial measuring devices and novel experimental assemblies for measuring solubility of hydrogen and nitrogen during melting and mold fill...

  12. Water Soluble Polymers as Proton Exchange Membranes for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Bing-Joe Hwang

    2012-03-01

    Full Text Available The relentless increase in the demand for useable power from energy-hungry economies continues to drive energy-material related research. Fuel cells, as a future potential power source that provide clean-at-the-point-of-use power offer many advantages such as high efficiency, high energy density, quiet operation, and environmental friendliness. Critical to the operation of the fuel cell is the proton exchange membrane (polymer electrolyte membrane responsible for internal proton transport from the anode to the cathode. PEMs have the following requirements: high protonic conductivity, low electronic conductivity, impermeability to fuel gas or liquid, good mechanical toughness in both the dry and hydrated states, and high oxidative and hydrolytic stability in the actual fuel cell environment. Water soluble polymers represent an immensely diverse class of polymers. In this comprehensive review the initial focus is on those members of this group that have attracted publication interest, principally: chitosan, poly (ethylene glycol, poly (vinyl alcohol, poly (vinylpyrrolidone, poly (2-acrylamido-2-methyl-1-propanesulfonic acid and poly (styrene sulfonic acid. The paper then considers in detail the relationship of structure to functionality in the context of polymer blends and polymer based networks together with the effects of membrane crosslinking on IPN and semi IPN architectures. This is followed by a review of pore-filling and other impregnation approaches. Throughout the paper detailed numerical results are given for comparison to today’s state-of-the-art Nafion® based materials.

  13. Quantitative analysis of soluble elements in environmental waters by PIXE

    International Nuclear Information System (INIS)

    Niizeki, T.; Kawasaki, K.; Adachi, M.; Tsuji, M.; Hattori, T.

    1999-01-01

    We have started PIXE research for environmental science at Van de Graaff accelerator facility in Tokyo Institute of Technology. Quantitative measurements of soluble fractions in river waters have been carried out using the preconcentrate method developed in Tohoku University. We reveal that this PIXE target preparation can be also applied to waste water samples. (author)

  14. Solubility of carbon dioxide, methane, and ethane in 1-butanol and saturated liquid densities and viscosities

    International Nuclear Information System (INIS)

    Kariznovi, Mohammad; Nourozieh, Hossein; Abedi, Jalal

    2013-01-01

    Highlights: • Experimental solubilities of CH 4 , C 2 H 6 , and CO 2 in 1-butanol and saturated liquid properties. • Solubilities and saturated liquid densities were predicted with SRK and PR EOS. • Solubility of C 2 H 6 in 1-butanol is higher than CH 4 and CO 2 . • Liquid density and viscosity reduces with dissolution of CH 4 and C 2 H 6 . • Dissolution of CO 2 increases liquid density and reduces liquid viscosity. -- Abstract: A designed pressure–volume–temperature (PVT) apparatus has been used to measure the (vapor + liquid) equilibrium properties of three binary mixtures (methane +, ethane +, and carbon dioxide + 1-butanol) at two temperatures (303 and 323) K and at the pressures up to 6 MPa. The solubility of the compressed gases in 1-butanol and the saturated liquid densities and viscosities were measured. In addition, the density and viscosity of pure 1-butanol were measured at two temperatures (303 and 323) K and at the pressures up to 10 MPa. The experimental results show that the solubility of the gases in 1-butanol increases with pressure and decreases with temperature. The dissolution of gases in 1-butanol causes a decline in the viscosity of liquid phase. The saturated liquid density follows a decreasing trend with the solubility of methane and ethane. However, the dissolution of carbon dioxide in 1-butanol leads to an increase in the density of liquid phase. The experimental data are well correlated with Soave–Redlich–Kwong (SRK) and Peng–Robinson (PR) equations of state (EOSs). SRK EOS was slightly superior for correlating the saturated liquid densities

  15. Anion Effects on Gas Solubility in Ionic Liquids

    OpenAIRE

    Anthony, Jennifer L.; Anderson, Jessica L.; Maginn, Edward J.; Brennecke, Joan F.

    2005-01-01

    This work presents the results of solubility measurements for a series of gases in 1-n-butyl-3-methyl imidazolium tetrafluoroborate and 1-n-butyl-3-methyl imidazolium bis(trifluoromethylsulfonyl) imide. The gases considered include benzene, carbon dioxide, nitrous oxide, ethylene, ethane, oxygen, and carbon monoxide. Carbon dioxide and oxygen solubilities are also reported in methyl-tributylammonium bis(trifluoromethylsulfonyl) imide, butyl-methyl pyrrolidinium bis(trifluoromethylsulfonyl) im...

  16. Enhancing the solubility and bioavailability of poorly water-soluble drugs using supercritical antisolvent (SAS) process.

    Science.gov (United States)

    Abuzar, Sharif Md; Hyun, Sang-Min; Kim, Jun-Hee; Park, Hee Jun; Kim, Min-Soo; Park, Jeong-Sook; Hwang, Sung-Joo

    2018-03-01

    Poor water solubility and poor bioavailability are problems with many pharmaceuticals. Increasing surface area by micronization is an effective strategy to overcome these problems, but conventional techniques often utilize solvents and harsh processing, which restricts their use. Newer, green technologies, such as supercritical fluid (SCF)-assisted particle formation, can produce solvent-free products under relatively mild conditions, offering many advantages over conventional methods. The antisolvent properties of the SCFs used for microparticle and nanoparticle formation have generated great interest in recent years, because the kinetics of the precipitation process and morphologies of the particles can be accurately controlled. The characteristics of the supercritical antisolvent (SAS) technique make it an ideal tool for enhancing the solubility and bioavailability of poorly water-soluble drugs. This review article focuses on SCFs and their properties, as well as the fundamentals of overcoming poorly water-soluble drug properties by micronization, crystal morphology control, and formation of composite solid dispersion nanoparticles with polymers and/or surfactants. This article also presents an overview of the main aspects of the SAS-assisted particle precipitation process, its mechanism, and parameters, as well as our own experiences, recent advances, and trends in development. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Micelles from lipid derivatives of water-soluble polymers as delivery systems for poorly soluble drugs.

    Science.gov (United States)

    Lukyanov, Anatoly N; Torchilin, Vladimir P

    2004-05-07

    Polymeric micelles have a whole set of unique characteristics, which make them very promising drug carriers, in particular, for poorly soluble drugs. Our review article focuses on micelles prepared from conjugates of water-soluble polymers, such as polyethylene glycol (PEG) or polyvinyl pyrrolidone (PVP), with phospholipids or long-chain fatty acids. The preparation of micelles from certain polymer-lipid conjugates and the loading of these micelles with various poorly soluble anticancer agents are discussed. The data on the characterization of micellar preparations in terms of their morphology, stability, longevity in circulation, and ability to spontaneously accumulate in experimental tumors via the enhanced permeability and retention (EPR) effect are presented. The review also considers the preparation of targeted immunomicelles with specific antibodies attached to their surface. Available in vivo results on the efficiency of anticancer drugs incorporated into plain micelles and immunomicelles in animal models are also discussed.

  18. 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

  19. Carcinogenicity assessment of water-soluble nickel compounds.

    Science.gov (United States)

    Goodman, Julie E; Prueitt, Robyn L; Dodge, David G; Thakali, Sagar

    2009-01-01

    IARC is reassessing the human carcinogenicity of nickel compounds in 2009. To address the inconsistencies among results from studies of water-soluble nickel compounds, we conducted a weight-of-evidence analysis of the relevant epidemiological, toxicological, and carcinogenic mode-of-action data. We found the epidemiological evidence to be limited, in that some, but not all, data suggest that exposure to soluble nickel compounds leads to increased cancer risk in the presence of certain forms of insoluble nickel. Although there is no evidence that soluble nickel acts as a complete carcinogen in animals, there is limited evidence that suggests it may act as a tumor promoter. The mode-of-action data suggest that soluble nickel compounds will not be able to cause genotoxic effects in vivo because they cannot deliver sufficient nickel ions to nuclear sites of target cells. Although the mode-of-action data suggest several possible non-genotoxic effects of the nickel ion, it is unclear whether soluble nickel compounds can elicit these effects in vivo or whether these effects, if elicited, would result in tumor promotion. The mode-of-action data equally support soluble nickel as a promoter or as not being a causal factor in carcinogenesis at all. The weight of evidence does not indicate that soluble nickel compounds are complete carcinogens, and there is only limited evidence that they could act as tumor promoters.

  20. Solubility studies of Np(V) in simulated underground water

    International Nuclear Information System (INIS)

    Zhang Yingjie; Ren Lilong; Jiao Haiyang; Yao Jun; Su Xiguang; Fan Xianhua

    2004-01-01

    The solubility of Np(V) in simulated underground water has been measured with the variation of pH, storage time (0-100 days). All experiments were performed in an Ar glove box which contained high purity Ar, with an oxygen content of less than 5ppm. Experimental results show that the solubility of Np(V) in simulated underground water decreased with increasing pH value of solution; the solubility of Np(V) in simulated underground water determined at different pH is : pH=6.96, [Np(V)]=(3.52±0.37) x 10 -4 mol/L; pH=8.04, [Np(V)]=(8.24±0.32) x 10 -5 mol/L; pH=9.01, [Np(V)]=(3.04±0.48) x 10'- 5 mol/L, respectively. (author)

  1. Oral formulation strategies to improve solubility of poorly water-soluble drugs.

    Science.gov (United States)

    Singh, Abhishek; Worku, Zelalem Ayenew; Van den Mooter, Guy

    2011-10-01

    In the past two decades, there has been a spiraling increase in the complexity and specificity of drug-receptor targets. It is possible to design drugs for these diverse targets with advances in combinatorial chemistry and high throughput screening. Unfortunately, but not entirely unexpectedly, these advances have been accompanied by an increase in the structural complexity and a decrease in the solubility of the active pharmaceutical ingredient. Therefore, the importance of formulation strategies to improve the solubility of poorly water-soluble drugs is inevitable, thus making it crucial to understand and explore the recent trends. Drug delivery systems (DDS), such as solid dispersions, soluble complexes, self-emulsifying drug delivery systems (SEDDS), nanocrystals and mesoporous inorganic carriers, are discussed briefly in this review, along with examples of marketed products. This article provides the reader with a concise overview of currently relevant formulation strategies and proposes anticipated future trends. Today, the pharmaceutical industry has at its disposal a series of reliable and scalable formulation strategies for poorly soluble drugs. However, due to a lack of understanding of the basic physical chemistry behind these strategies, formulation development is still driven by trial and error.

  2. OCTANOL/WATER PARTITION COEFFICIENTS AND WATER SOLUBILITIES OF PHTHALATE ESTERS

    Science.gov (United States)

    Measurements of the octanol/water partition coefficients (K-ow) and water solubilities of di-n-octyl phthalate (DnOP) and di-n-decyl phthalate (DnDP) by the slow-stirring method are reported. The water solubility was also measured for di-n-hexyl phthalate (DnHP). The log K-ow val...

  3. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate

    Directory of Open Access Journals (Sweden)

    Yousaf AM

    2016-01-01

    Full Text Available Abid Mehmood Yousaf,1,2 Omer Mustapha,1 Dong Wuk Kim,1 Dong Shik Kim,1 Kyeong Soo Kim,1 Sung Giu Jin,1 Chul Soon Yong,3 Yu Seok Youn,4 Yu-Kyoung Oh,5 Jong Oh Kim,3 Han-Gon Choi1 1College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Gyeonggi, South Korea; 2Faculty of Pharmacy, University of Central Punjab, Johar, Lahore, Pakistan; 3College of Pharmacy, Yeungnam University, Gyongsan, North Gyeongsang, 4School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi, 5College of Pharmacy, Seoul National University, Seoul, South Korea Purpose: The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate.Methods: Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP and Labrafil® M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion.Results: All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1

  4. The addition zirconium effect on the solubility and activity of sulfur in liquid iron

    International Nuclear Information System (INIS)

    Burylev, B.P.; Mojsov, L.P.

    1994-01-01

    Critical analysis of reference data on thermodynamic properties of zirconium sulfides is conducted for evaluation of zirconium desulfonation ability in liquid steel. Sulfur solubility dependence on zirconium concentration in liquid iron is presented. Curves of sulfur solubility in liquid iron in the presence of other elements, including titanium, manganese, vanadium and chromium are presented for comparison. It is shown that equilibrium concentration of sulfur is much lower than standard sulfur concentrations in steel, therefore zirconium appears to be the best desulfonator among the metals considered

  5. Solubility and selectivity of CO2 in ether-functionalized imidazolium ionic liquids

    International Nuclear Information System (INIS)

    Zhou, Lingyun; Shang, Xiaomin; Fan, Jing; Wang, Jianji

    2016-01-01

    Highlights: • Solubilities of CO 2 , N 2 and O 2 in [EOMmim][PF 6 ] and [EOMmim][Tf 2 N] were determined. • Introduction of ether group results in increase of CO 2 /N 2 and CO 2 /O 2 selectivity. • The solution of CO 2 in the ionic liquids is an exothermic and orderly process. • Experimental solubility data have been well correlated by Pitzer model. - Abstract: Ionic liquids are widely recognized new materials in carbon dioxide capture and separation technology. In this work, we synthesized and characterized two kinds of ether-functionalized imidazolium ionic liquids, 1-methoxyethyl-3-methylimidazolium hexafluoroborate ([EOMmim][PF 6 ]) and 1-methoxyethyl-3-methylimidazolium bis(trifluoro-methylsulfony)imide ([EOMmim][Tf 2 N]). Solubility values of CO 2 in these ionic liquids were determined by isometric weight method at the temperatures from 298.15 K to 343.15 K and the pressure up to 5.185 MPa. Furthermore, solubilities of other flue gases, N 2 and O 2 , in these two ionic liquids were also measured at 303.15 K. It was shown that little influence had been exerted on CO 2 solubility by the introduction of ether groups on the cation, but it decreased N 2 and O 2 solubility, resulting in the remarkable increase of CO 2 /N 2 and CO 2 /O 2 selectivity. In addition, the solubility data were well correlated by Pitzer model, and the standard state solution Gibbs energy, solution enthalpy and solution entropy of CO 2 in the two ionic liquids were reported. Regeneration characteristics of the investigated ionic liquids was also studied by vacuum desorption and atmospheric desorption, respectively.

  6. Solubilization of poorly water-soluble drugs using solid dispersions.

    Science.gov (United States)

    Tran, Thao T-D; Tran, Phuong H-L; Khanh, Tran N; Van, Toi V; Lee, Beom-Jin

    2013-08-01

    Many new drugs have been discovered in pharmaceutical industry and exposed their surprised potential therapeutic effects. Unfortunately, these drugs possess low absorption and bioavailability since their solubility limitation in water. Solid dispersion (SD) is the current technique gaining so many attractions from scientists due to its effect on improving solubility and dissolution rate of poorly water-soluble drugs. A number of patents including the most recent inventions have been undertaken in this review to address various respects of this strategy in solubilization of poorly watersoluble drugs including type of carriers, preparation methods and view of technologies used to detect SD properties and mechanisms with the aim to accomplish a SD not only effective on enhanced bioavailability but also overcome difficulties associated with stability and production. Future prospects are as well discussed with an only hope that many developments and researches in this field will be successfully reached and contributed to commercial use for treatment as much as possible.

  7. Solubility of magnetite in high temperature water and an approach to generalized solubility computations

    International Nuclear Information System (INIS)

    Dinov, K.; Ishigure, K.; Matsuura, C.; Hiroishi, D.

    1993-01-01

    Magnetite solubility in pure water was measured at 423 K in a fully teflon-covered autoclave system. A fairly good agreement was found to exist between the experimental data and calculation results obtained from the thermodynamical model, based on the assumption of Fe 3 O 4 dissolution and Fe 2 O 3 deposition reactions. A generalized thermodynamical approach to the solubility computations under complex conditions on the basis of minimization of the total system Gibbs free energy was proposed. The forms of the chemical equilibria were obtained for various systems initially defined and successfully justified by the subsequent computations. A [Fe 3+ ] T -[Fe 2+ ] T phase diagram was introduced as a tool for systematic understanding of the magnetite dissolution phenomena in pure water and under oxidizing and reducing conditions. (orig.)

  8. Solubility of uranium in liquid gallium, indium and their alloys

    International Nuclear Information System (INIS)

    Volkovich, Vladimir A.; Maltsev, Dmitry S.; Yamschikov, Leonid F.; Osipenko, Alexander G.; Kormilitsyn, Mikhail V.

    2014-01-01

    Pyrochemical reprocessing of spent nuclear fuels (SNF) employing molten salts and liquid metals as working media is considered as a possible alternative to the existing liquid extraction (PUREX) processes. Liquid salts and metals allow reprocessing highly irradiated high burn-up fuels with short cooling times, including the fuels of fast neutron reactors. Pyrochemical technology opens a way to practical realization of short closed fuel cycle. Liquid low-melting metals are immiscible with molten salts and can be effectively used for separation (or selective extraction) of SNF components dissolved in fused salts. Binary or ternary alloys of eutectic compositions can be employed to lower the melting point of the metallic phase. However, the information on SNF components behaviour and properties in ternary liquid metal alloys is very scarce

  9. IMPROVEMENT OF SOLUBILITY OF BADLY WATER SOLUBLE DRUG (IBUPROFEN) BY USING SURFACTANTS AND CARRIERS

    OpenAIRE

    Md. Zakaria Faruki*, Rishikesh, Elizabeth Razzaque, Mohiuddin Ahmed Bhuiyan

    2013-01-01

    ABSTRACT: Although there was a great interest in solid dispersion systems during the past four decades to increase dissolution rate and bioavailability of badly water-soluble drugs, their profitable use has been very limited, primarily because of manufacturing difficulties and stability problems. In this study solid solutions of drugs were generally produced by fusion method. The drug along with the excipients (surfactants and carriers) was heated first and then hardened by cooling to room te...

  10. Physical and ionic characteristics in water soluble fraction (WSF) of ...

    African Journals Online (AJOL)

    The values of ionic and physical characteristics at 25, 50 and 100% water soluble fraction (WSF) of Olomoro well-head crude oil before and after exposure to Azolla africana were investigated. The WSF values before and after exposure to the plants showed that more ions were available after the introduction of the test plant.

  11. Bioremediation prospects of fungi isolated from water soluble ...

    African Journals Online (AJOL)

    The fungi associated with water soluble fraction (WSF) of crude oil from two different locations were investigated. The samples were collected from Ezibin oil well (Sample A), Okwagbe village in Ughelli South Local Government Area of Delta State and from NPDC laboratory (Sample B) in Benin City, Oredo Local ...

  12. Process for radiation cocrosslinking water soluble polymers and products thereof

    International Nuclear Information System (INIS)

    Assarsson, P.G.; King, P.A.

    1976-01-01

    Poly(ethylene oxide) and at least one other water soluble polymer are conveniently cocrosslinked by exposing aqueous systems of the polymers to high energy irradiation. The resulting products are insoluble hydrophilic gels which can contain or when dried absorb large quantities of aqueous fluids and hence are useful as absorbing media for disposable absorbent articles, agricultural applications and the like

  13. Water-soluble diphosphadiazacyclooctanes as ligands for aqueous organometallic catalysis

    KAUST Repository

    Boulanger, Jérôme

    2012-12-01

    Two new water-soluble diphosphacyclooctanes been synthesized and characterized by NMR and surface tension measurements. Both phosphanes proved to coordinate rhodium in a very selective way as well-defined bidentates were obtained. When used in Rh-catalyzed hydroformylation of terminal alkenes, both ligands positively impacted the reaction chemoselectivity. © 2012 Elsevier B.V.

  14. Determination of Carboxylic Acids and Water-soluble Inorganic Ions ...

    African Journals Online (AJOL)

    Atmospheric aerosol samples of PM2.5 and PM10 were collected in April–May 2011 from a rural site in Tanzania and analyzed for water-soluble inorganic ions and low molecular weight carboxylic acids using ion chromatography. PM2.5 and PM10 low-volume samplers with quartz fibre filters were deployed and aerosol ...

  15. Plasma concentrations of water.soluble vitamins in metabolic ...

    African Journals Online (AJOL)

    Context: Vitamins B1 (thiamine), B3 (niacin), B6 (pyridoxine), and C (ascorbic acid) are vital for energy, carbohydrate, lipid, and amino acid metabolism and in the regulation of the cellular redox state. Some studies have associated low levels of water.soluble vitamins with metabolic syndrome and its various components.

  16. Aggregation and Photophysical Properties of Water-Soluble Sapphyrins

    Czech Academy of Sciences Publication Activity Database

    Kubát, Pavel; Lang, Kamil; Zelinger, Zdeněk; Král, V.

    2004-01-01

    Roč. 395, - (2004), s. 82-86 ISSN 0009-2614 R&D Projects: GA AV ČR KSK4040110 Keywords : water-soluble * sapphyrins * photophysical Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.438, year: 2004

  17. Short Communication Relationships between the water solubility of ...

    African Journals Online (AJOL)

    132. Short Communication. Relationships between the water solubility of roughage dry matter and certain chemical characteristics. J.W. Cilliers- and H.J. Cilliers. North West Agricultural Development lnstitute, Private. Bag X804, Potchefstroom, 2520 Republic of South Africa. Received 17 May 1995; accepted 8 August 1995.

  18. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    International Nuclear Information System (INIS)

    Qi Guozhen; Wang Jindi; Lin Yiqing

    1999-01-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed

  19. Synthesis of water soluble photo-initiators of thioxanthone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Guozhen, Qi; Jindi, Wang; Yiqing, Lin [Inst. of Fine Chemicals ECUST, Shanghai (China)

    1999-07-01

    Eight new photo-initiators of water-soluble thioxanthone derivatives were prepared. These compounds were identified by IR, NMR, MS and elemental analysis etc. The UV absorption wavelength, molar absorption coefficient and fluorescent quantum yield were determined. Furthermore, the relationship between structure and properties was discussed.

  20. Water-soluble diphosphadiazacyclooctanes as ligands for aqueous organometallic catalysis

    KAUST Repository

    Boulanger, Jé rô me; Bricout, Hervé ; Tilloy, Sé bastien; Fihri, Aziz; Len, Christophe; Hapiot, Fré dé ric; Monflier, É ric

    2012-01-01

    Two new water-soluble diphosphacyclooctanes been synthesized and characterized by NMR and surface tension measurements. Both phosphanes proved to coordinate rhodium in a very selective way as well-defined bidentates were obtained. When used in Rh-catalyzed hydroformylation of terminal alkenes, both ligands positively impacted the reaction chemoselectivity. © 2012 Elsevier B.V.

  1. Selective Photooxidation Reactions using Water-Soluble Anthraquinone Photocatalysts

    NARCIS (Netherlands)

    Zhang, W.; Gacs, Jenő; Arends, I.W.C.E.; Hollmann, F.

    2017-01-01

    The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible

  2. Liquid Salt as Green Solvent: A Novel Eco-Friendly Technique to Enhance Solubility and Stability of Poorly Soluble Drugs

    Science.gov (United States)

    Patel, Anant A.

    As a result of tremendous efforts in past few decades, various techniques have been developed in order to resolve solubility issues associated with class II and IV drugs, However, majority of these techniques offer benefits associated with certain drawbacks; majorly including low drug loading, physical instability on storage and excessive use of environmentally challenging organic solvents. Hence, current effort was to develop an eco-friendly technique using liquid salt as green solvent, which can offer improvement in dissolution while maintaining long term stability. The liquid salt formulations (LSF) of poorly soluble model drugs ibuprofen, gemfibrozil and indomethacin were developed using 1-Ethyl-3-methylimidazolium ethyl sulfate (EMIM ES) as a non-toxic and environmentally friendly alternate to organic solvents. Liquid medications containing clear solutions of drug, EMIM ES and polysorbate 20, were adsorbed onto porous carrier Neusilin US2 to form free flowing powder. The LSF demonstrated greater rate and extent of dissolution compared to crystalline drugs. The dissolution data revealed that more than 80% drug release from LSF within 20 mins compared to less than 18% release from pure drugs. As high as 70% w/w liquid loading was achieved while maintaining good flowability and compressibility. In addition, the LSF samples exposed to high temperature and high humidity i.e. 40°C/80% RH for 8 weeks, demonstrated excellent physical stability without any signs of precipitation or crystallization. As most desirable form of administration is tablet, the developed liquid salt formulations were transformed into tablets using design of experiment approach by Design Expert Software. The tablet formulation composition and critical parameter were optimized using Box-Behnken Design. This innovative liquid salt formulation technique offered improvement in dissolution rate and extent as well as contributed to excellent physical stability on storage. Moreover, this formulation

  3. Temperature dependence on mutual solubility of binary (methanol + limonene) mixture and (liquid + liquid) equilibria of ternary (methanol + ethanol + limonene) mixture

    International Nuclear Information System (INIS)

    Tamura, Kazuhiro; Li Xiaoli; Li Hengde

    2009-01-01

    Mutual solubility data of the binary (methanol + limonene) mixture at the temperatures ranging from 288.15 K close to upper critical solution temperature, and ternary (liquid + liquid) equilibrium (tie-lines) of the (methanol + ethanol + limonene) mixture at the temperatures (288.15, 298.15, and 308.15) K have been obtained. The experimental results have been represented accurately in terms of the extended and modified UNIQUAC models with binary parameters, compared with the UNIQUAC model. The temperature dependence of binary and ternary (liquid + liquid) equilibrium for the binary (methanol + limonene) and ternary (methanol + ethanol + limonene) mixtures could be calculated successfully using the extended and modified UNIQUAC model

  4. Some physicochemical aspects of water-soluble mineral flotation.

    Science.gov (United States)

    Wu, Zhijian; Wang, Xuming; Liu, Haining; Zhang, Huifang; Miller, Jan D

    2016-09-01

    Some physicochemical aspects of water-soluble mineral flotation including hydration phenomena, associations and interactions between collectors, air bubbles, and water-soluble mineral particles are presented. Flotation carried out in saturated salt solutions, and a wide range of collector concentrations for effective flotation of different salts are two basic aspects of water-soluble mineral flotation. Hydration of salt ions, mineral particle surfaces, collector molecules or ions, and collector aggregates play an important role in water-soluble mineral flotation. The adsorption of collectors onto bubble surfaces is suggested to be the precondition for the association of mineral particles with bubbles. The association of collectors with water-soluble minerals is a complicated process, which may include the adsorption of collector molecules or ions onto such surfaces, and/or the attachment of collector precipitates or crystals onto the mineral surfaces. The interactions between the collectors and the minerals include electrostatic and hydrophobic interactions, hydrogen bonding, and specific interactions, with electrostatic and hydrophobic interactions being the common mechanisms. For the association of ionic collectors with minerals with an opposite charge, electrostatic and hydrophobic interactions could have a synergistic effect, with the hydrophobic interactions between the hydrophobic groups of the previously associated collectors and the hydrophobic groups of oncoming collectors being an important attractive force. Association between solid particles and air bubbles is the key to froth flotation, which is affected by hydrophobicity of the mineral particle surfaces, surface charges of mineral particles and bubbles, mineral particle size and shape, temperature, bubble size, etc. The use of a collector together with a frother and the use of mixed surfactants as collectors are suggested to improve flotation. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Nanonization strategies for poorly water-soluble drugs.

    Science.gov (United States)

    Chen, Huabing; Khemtong, Chalermchai; Yang, Xiangliang; Chang, Xueling; Gao, Jinming

    2011-04-01

    Poor water solubility for many drugs and drug candidates remains a major obstacle to their development and clinical application. Conventional formulations to improve solubility suffer from low bioavailability and poor pharmacokinetics, with some carriers rendering systemic toxicities (e.g. Cremophor(®) EL). In this review, several major nanonization techniques that seek to overcome these limitations for drug solubilization are presented. Strategies including drug nanocrystals, nanoemulsions and polymeric micelles are reviewed. Finally, perspectives on existing challenges and future opportunities are highlighted. Published by Elsevier Ltd.

  6. (Liquid + liquid), (solid + liquid), and (solid + liquid + liquid) equilibria of systems containing cyclic ether (tetrahydrofuran or 1,3-dioxolane), water, and a biological buffer MOPS

    International Nuclear Information System (INIS)

    Altway, Saidah; Taha, Mohamed; Lee, Ming-Jer

    2015-01-01

    Graphical abstract: - Highlights: • MOPS buffer induced liquid phase splitting for mixtures of water with THF or 1,3-dioxolane. • Phase boundaries of LLE, SLE, and SLLE were determined experimentally. • Tie-lines at LLE and at SLLE were also measured. • Phase diagrams of MOPS + water + THF or 1,3-dioxolane are prepared. • LLE tie-line data are correlated satisfactorily with the NRTL model. - Abstract: Two liquid phases were formed as the addition of a certain amount of biological buffer 3-(N-morpholino)propane sulfonic acid (MOPS) in the aqueous solutions of tetrahydrofuran (THF) or 1,3-dioxolane. To evaluate the feasibility of recovering the cyclic ethers from their aqueous solutions with the aid of MOPS, we determined experimentally the phase diagrams of the ternary systems of {cyclic ether (THF or 1,3-dioxolane) + water + MOPS} at T = 298.15 K under atmospheric pressure. In this study, the solubility data of MOPS in water and in the mixed solvents of water/cyclic ethers were obtained from the results of a series of density measurements, while the (liquid + liquid) and the (solid + liquid + liquid) phase boundaries were determined by visually inspection. Additionally, the tie-line results for (liquid + liquid) equilibrium (LLE) and for (solid + liquid + liquid) equilibrium (SLLE) were measured using an analytical method. The reliability of the experimental LLE tie-line results data was validated by using the Othmer–Tobias correlation. These LLE tie-line values were correlated well with the NRTL model. The phase diagrams obtained from this study reveal that MOPS is a feasible green auxiliary agent to recover the cyclic ethers from their aqueous solutions, especially for 1,3-dioxolane

  7. 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,

  8. Water-Soluble Vitamin E-Tocopheryl Phosphate.

    Science.gov (United States)

    Zingg, Jean-Marc

    The hydrophobicity of vitamin E poses transport and metabolic challenges to regulate its bioavailability and to prevent its accumulation in lipid-rich tissues such as adipose tissue, brain, and liver. Water-soluble precursors of vitamin E (α-tocopherol, αT), such as its esters with acetate (αTA), succinate (αTS), or phosphate (αTP), have increased solubility in water and stability against reaction with free radicals, but they are rapidly converted during their uptake into the lipid-soluble vitamin E. Therefore, the bioavailability of these precursors as intact molecules is low; nevertheless, at least for αTS and αTP, the recent research has revealed unique regulatory effects on signal transduction and gene expression and the modulation of cellular events ranging from proliferation, survival/apoptosis, lipid uptake and metabolism, phagocytosis, long term potentiation, cell migration, telomere maintenance, and angiogenesis. Moreover, water-soluble derivatives of vitamin E including some based on αTP are increasingly used as components of nanocarriers for enhanced and targeted delivery of drugs and other molecules (vitamins, including αT and αTP itself, vitamin D3, carnosine, caffeine, docosahexaenoic acid (DHA), insulin) and cofactors such as coenzyme Q10. In this review, the chemical characteristics, transport, metabolic pathways, and molecular mechanisms of action of αTP in cells and tissues are summarized and put into perspective with its possible role in the prevention of a number of diseases. © 2018 Elsevier Inc. All rights reserved.

  9. Dissolution rates and solubility of some metals in liquid gallium and aluminum

    International Nuclear Information System (INIS)

    Yatsenko, S P; Sabirzyanov, N A; Yatsenko, A S

    2008-01-01

    The effect of liquid gallium and aluminum on some hard metals leading to dissolution and formation of intermetallic compounds (IMC) under static conditions and rotation of a specimen is studied. The solubility parameters from the Clapeyron-Clausius equation were considered to estimate the stability of still not studied metals. The presented experimental data on solubility and corrosion in a wide temperature range allow to calculate a number of parameters useful in manufacturing and application of master-alloys

  10. 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.

  11. 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.

  12. Solubility effects in waste-glass/demineralized-water systems

    International Nuclear Information System (INIS)

    Fullam, H.T.

    1981-06-01

    Aqueous systems involving demineralized water and four glass compositions (including standins for actinides and fission products) at temperatures of up to 150 0 C were studied. Two methods were used to measure the solubility of glass components in demineralized water. One method involved approaching equilibrium from subsaturation, while the second method involved approaching equilibrium from supersaturation. The aqueous solutions were analyzed by induction-coupled plasma spectrometry (ICP). Uranium was determined using a Scintrex U-A3 uranium analyzer and zinc and cesium were determined by atomic absorption. The system that results when a waste glass is contacted with demineralized water is a complex one. The two methods used to determine the solubility limits gave very different results, with the supersaturation method yielding much higher solution concentrations than the subsaturation method for most of the elements present in the waste glasses. The results show that it is impossible to assign solubility limits to the various glass components without thoroughly describing the glass-water systems. This includes not only defining the glass type and solution temperature, but also the glass surface area-to-water volume ratio (S/V) of the system and the complete thermal history of the system. 21 figures, 22 tables

  13. The structure of liquid water

    International Nuclear Information System (INIS)

    Marin, B.

    1969-01-01

    We have tried to expose a bibliography so complete as possible on structure of liquid water. One synthesis of the different models of water structure is presently impossible, so, we have exposed the main properties of water. We have pointed out the new hypotheses on the electronic structure of water molecule and on the theory of hydrogen bond. After that, we have put together the studies of structure by spectroscopy and given the main deductions of some workers on this subject. We have also exposed the characteristics of processes: relaxation and dielectric constant, influence of temperature on structure. At last, we have considered briefly the partition and thermodynamic functions established from the various models proposed. (author) [fr

  14. Solubility of gases in 1-alkyl-3methylimidazolium alkyl sulfate ionic liquids: Experimental determination and modeling

    International Nuclear Information System (INIS)

    Bermejo, María Dolores; Fieback, Tobias M.; Martín, Ángel

    2013-01-01

    Highlights: ► The solubility of CO 2 , CH 4 and C 2 H 6 in [emim][EtSO 4 ] is measured with a magnetic suspension balance. ► New data and literature results have been modeled with a Group Contribution equation of state. ► A specific group definition is required to model data of ionic liquids with a [MeSO 4 ] anion. ► Deviations between model and experiments are lower than 10% in most cases. ► Deviations of 34% are observed in the case of the solubility of ethane in the ionic liquid. -- Abstract: The solubility of different gases (carbon dioxide, methane, ethane, carbon monoxide and hydrogen) in ionic liquids with an alkyl sulfate anion has been modeled with the Group Contribution equation of state developed by Skjold-Jørgensen. New gas solubility measurements have been carried out with a high pressure magnetic suspension balance in order to cover pressure and temperature ranges not considered in previous studies and to obtain more experimental information for the correlation of parameters of the equation of state. New solubility measurements include the solubility of carbon dioxide in 1-ethyl 3-methyl imidazolium ethyl sulfate [emim][EtSO 4 ] at temperatures of 298 K and 348 K and pressures ranging from 0.3 MPa to 6.5 MPa, the solubility of methane in [emim][EtSO 4 ] at a temperature of 293 K and pressures ranging from 0.2 MPa to 10.2 MPa, and the solubility of ethane in [emim][EtSO 4 ] at temperatures of 323 K and 350 K and pressures ranging from 0.2 MPa to 4 MPa. Results show that the Group Contribution equation of state can be used to describe the solubility of gases in alkyl sulfate ionic liquids as well as infinite dilution coefficients of alkanes in the ionic liquids, with average deviations between experiments and calculations ranging from 1% to 10% in the case of mixtures with CO 2 , CO, CH 4 and H 2 with the alkyl sulfate ionic liquids to up to 34% in the case of the solubility of ethane in [emim][EtSO 4

  15. Determination and correlation of solubility and solution thermodynamics of oxiracetam in three (alcohol + water) binary solvents

    International Nuclear Information System (INIS)

    Li, Kangli; Du, Shichao; Wu, Songgu; Cai, Dongchen; Wang, Jinxu; Zhang, Dejiang; Zhao, Kaifei; Yang, Peng; Yu, Bo; Guo, Baisong; Li, Daixi; Gong, Junbo

    2016-01-01

    Highlights: • The solubility of racemic oxiracetam in three binary solvents were determined. • The experimental solubility of racemic oxiracetam were correlated by four models. • The dissolution thermodynamic properties of racemic oxiracetam were calculated. - Abstract: In this paper, we proposed a static analysis method to experimentally determine the (solid + liquid) equilibrium of racemic oxiracetam in (methanol + water), (ethanol + water) and (isopropanol + water) binary solvents with alcohol mole fraction ranging from 0.30 to 0.90 at atmosphere pressure (p = 0.1 MPa). For the experiments, the temperatures range from (283.15 to 308.15) K. The results showed that the solubility of oxiracetam increased with the increasing temperature, while decreased with the increasing organic solvent fraction in all three tested binary solvent systems. The modified Apelblat model, the CNIBS/Redlich–Kister model, the combined version of Jouyban–Acree model and the NRTL model were employed to correlate the measured solubility values, respectively. Additionally, some of the thermodynamic properties which can help to evaluate its dissolution behavior were obtained based on the NRTL model.

  16. Improved intestinal absorption of a poorly water-soluble oral drug using mannitol microparticles containing a nanosolid drug dispersion.

    Science.gov (United States)

    Nishino, Yukiko; Kubota, Aya; Kanazawa, Takanori; Takashima, Yuuki; Ozeki, Tetsuya; Okada, Hiroaki

    2012-11-01

    A nozzle for a spray dryer that can prepare microparticles of water-soluble carriers containing various nanoparticles in a single step was previously developed in our laboratory. To enhance the solubility and intestinal absorption of poorly water-soluble drugs, we used probucol (PBL) as a poorly water-soluble drug, mannitol (MAN) as a water-soluble carrier for the microparticles, and EUDRAGIT (EUD) as a polymer vehicle for the solid dispersion. PBL-EUD-acetone-methanol and aqueous MAN solutions were simultaneously supplied through different liquid passages of the spray nozzle and dried together. PBL-EUD solid dispersion was nanoprecipitated in the MAN solution using an antisolvent mechanism and rapidly dried by surrounding it with MAN. PBL in the dispersion vehicle was amorphous and had higher physical stability according to powder X-ray diffraction and differential scanning calorimetry analysis. The bioavailability of PBL in PBL-EUD S-100-MAN microparticles after oral administration in rats was markedly higher (14- and 6.2-fold, respectively) than that of the original PBL powder and PBL-MAN microparticles. These results demonstrate that the composite microparticles containing a nanosized solid dispersion of a poorly water-soluble drug prepared using the spray nozzle developed by us should be useful to increase the solubility and bioavailability of drugs after oral administration. Copyright © 2012 Wiley Periodicals, Inc.

  17. Data representing two separate LC-MS methods for detection and quantification of water-soluble and fat-soluble vitamins in tears and blood serum

    Directory of Open Access Journals (Sweden)

    Maryam Khaksari

    2017-04-01

    Full Text Available Two separate liquid chromatography (LC-mass spectrometry (MS methods were developed for determination and quantification of water-soluble and fat-soluble vitamins in human tear and blood serum samples. The water-soluble vitamin method was originally developed to detect vitamins B1, B2, B3 (nicotinamide, B5, B6 (pyridoxine, B7, B9 and B12 while the fat-soluble vitamin method detected vitamins A, D3, 25(OHD3, E and K1. These methods were then validated with tear and blood serum samples. In this data in brief article, we provide details on the two LC-MS methods development, methods sensitivity, as well as precision and accuracy for determination of vitamins in human tears and blood serum. These methods were then used to determine the vitamin concentrations in infant and parent samples under a clinical study which were reported in "Determination of Water-Soluble and Fat-Soluble Vitamins in Tears and Blood Serum of Infants and Parents by Liquid Chromatography/Mass Spectrometry DOI:10.1016/j.exer.2016.12.007 [1]". This article provides more details on comparison of vitamin concentrations in the samples with the ranges reported in the literature along with the medically accepted normal ranges. The details on concentrations below the limits of detection (LOD and limits of quantification (LOQ are also discussed. Vitamin concentrations were also compared and cross-correlated with clinical data and nutritional information. Significant differences and strongly correlated data were reported in [1]. This article provides comprehensive details on the data with slight differences or slight correlations.

  18. Data representing two separate LC-MS methods for detection and quantification of water-soluble and fat-soluble vitamins in tears and blood serum.

    Science.gov (United States)

    Khaksari, Maryam; Mazzoleni, Lynn R; Ruan, Chunhai; Kennedy, Robert T; Minerick, Adrienne R

    2017-04-01

    Two separate liquid chromatography (LC)-mass spectrometry (MS) methods were developed for determination and quantification of water-soluble and fat-soluble vitamins in human tear and blood serum samples. The water-soluble vitamin method was originally developed to detect vitamins B 1 , B 2 , B 3 (nicotinamide), B 5 , B 6 (pyridoxine), B 7 , B 9 and B 12 while the fat-soluble vitamin method detected vitamins A, D 3 , 25(OH)D 3, E and K 1 . These methods were then validated with tear and blood serum samples. In this data in brief article, we provide details on the two LC-MS methods development, methods sensitivity, as well as precision and accuracy for determination of vitamins in human tears and blood serum. These methods were then used to determine the vitamin concentrations in infant and parent samples under a clinical study which were reported in "Determination of Water-Soluble and Fat-Soluble Vitamins in Tears and Blood Serum of Infants and Parents by Liquid Chromatography/Mass Spectrometry DOI:10.1016/j.exer.2016.12.007 [1]". This article provides more details on comparison of vitamin concentrations in the samples with the ranges reported in the literature along with the medically accepted normal ranges. The details on concentrations below the limits of detection (LOD) and limits of quantification (LOQ) are also discussed. Vitamin concentrations were also compared and cross-correlated with clinical data and nutritional information. Significant differences and strongly correlated data were reported in [1]. This article provides comprehensive details on the data with slight differences or slight correlations.

  19. Enhancing the Solubility and Oral Bioavailability of Poorly Water-Soluble Drugs Using Monoolein Cubosomes.

    Science.gov (United States)

    Ali, Md Ashraf; Kataoka, Noriko; Ranneh, Abdul-Hackam; Iwao, Yasunori; Noguchi, Shuji; Oka, Toshihiko; Itai, Shigeru

    2017-01-01

    Monoolein cubosomes containing either spironolactone (SPI) or nifedipine (NI) were prepared using a high-pressure homogenization technique and characterized in terms of their solubility and oral bioavailability. The mean particle size, polydispersity index (PDI), zeta potential, solubility and encapsulation efficiency (EE) values of the SPI- and NI-loaded cubosomes were determined to be 90.4 nm, 0.187, -13.4 mV, 163 µg/mL and 90.2%, and 91.3 nm, 0.168, -12.8 mV, 189 µg/mL and 93.0%, respectively, which were almost identical to those of the blank cubosome. Small-angle X-ray scattering analyses confirmed that the SPI-loaded, NI-loaded and blank cubosomes existed in the cubic space group Im3̄m. The lattice parameters of the SPI- and NI-loaded cubosomes were 147.6 and 151.6 Å, respectively, making them almost identical to that of blank cubosome (151.0 Å). The in vitro release profiles of the SPI- and NI-loaded cubosomes showed that they released less than 5% of the drugs into various media over 12-48 h, indicating that most of the drug remained encapsulated within the cubic phase of their lipid bilayer. Furthermore, the in vivo pharmacokinetic results suggested that these cubosomes led to a considerable increase in the systemic oral bioavailability of the drugs compared with pure dispersions of the same materials. Notably, the stability results indicated that the mean particle size and PDI values of these cubosomes were stable for at least 4 weeks. Taken together, these results demonstrate that monoolein cubosomes represent promising drug carriers for enhancing the solubility and oral bioavailability of poorly water-soluble drugs.

  20. Water insoluble and soluble lipids for gene delivery.

    Science.gov (United States)

    Mahato, Ram I

    2005-04-05

    Among various synthetic gene carriers currently in use, liposomes composed of cationic lipids and co-lipids remain the most efficient transfection reagents. Physicochemical properties of lipid/plasmid complexes, such as cationic lipid structure, cationic lipid to co-lipid ratio, charge ratio, particle size and zeta potential have significant influence on gene expression and biodistribution. However, most cationic lipids are toxic and cationic liposomes/plasmid complexes do not disperse well inside the target tissues because of their large particle size. To overcome the problems associated with cationic lipids, we designed water soluble lipopolymers for gene delivery to various cells and tissues. This review provides a critical discussion on how the components of water insoluble and soluble lipids affect their transfection efficiency and biodistribution of lipid/plasmid complexes.

  1. Femtosecond study of laser dyes soluble in water: coumarins

    International Nuclear Information System (INIS)

    Cassara, Laurence

    1996-01-01

    Coumarins build up one of the great families of laser dyes, and this research thesis addresses the study of four water-soluble coumarins (ATC, DMATC, DATC, and CHOS) which are analogue to conventional coumarins (C120, C311, C1, and C102). These molecules are made water-soluble by substitution of the methyl group in position 4 by a polyether group. Mechanisms of deactivation are studied by means of time-resolved fluorescence and transient adsorption methods which allow the reaction dynamics of coumarins after light excitation to be studied. Several time scales, from femto- to nano-second, have been reached and allowed various processes to be studied: relaxation, solvation dynamics, solute orientation diffusion, process of deactivation of radiative and non-radiative relaxation in various solvents [fr

  2. Preparation of water soluble chitosan by hydrolysis using hydrogen peroxide.

    Science.gov (United States)

    Xia, Zhenqiang; Wu, Shengjun; Chen, Jinhua

    2013-08-01

    Chitosan is not soluble in water, which limits its wide application particularly in the medicine and food industry. In the present study, water soluble chitosan (WSC) was prepared by hydrolyzing chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid in homogeneous phase. Factors affecting hydrolysis were investigated and the optimal hydrolysis conditions were determined. The WSC structure was characterized by Fourier transform infrared spectroscopy. The resulting products were composed of chitooligosaccharides of DP 2-9. The WSC content of the product and the yield were 94.7% and 92.3% (w/w), respectively. The results indicate that WSC can be effectively prepared by hydrolysis of chitosan using hydrogen peroxide under the catalysis of phosphotungstic acid. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. PH-Induced Nanosegregation of Ritonavir to Lyotropic Liquid Crystal of Higher Solubility Than Crystalline Polymorphs

    International Nuclear Information System (INIS)

    Rodriguez-Spong, B.; Acciacca, A.; Fleisher, D.; Rodriguez-Hornedo, N.

    2009-01-01

    Birefringent spherical vesicles of ritonavir (RTV) are formed by increasing the pH of aqueous solutions from 1 to 3 or to 7 and by addition of water to ethanol solutions at room temperature. Increasing the pH creates supersaturation levels of 30--400. Upon this change in pH, the solutions become translucent, implying that some kind of RTV assembly was formed. Small spherical vesicles of narrow size distribution are detectable only after a few hours by optical microscopy. The vesicles show similar X-ray diffraction patterns and differential scanning calorimetry (DSC) behavior to amorphous RTV prepared by melt-quenching crystalline RTV. Examination by polarized optical microscopy suggests that these are lyotropic liquid crystalline (LLC) assemblies. Small-angle X-ray scattering and synchrotron X-ray diffraction further support the presence of orientational order that is associated with a nematic structure. RTV self-organizes into various phases as a result of the supersaturation created in aqueous solutions. The LLC vesicles do not fuse but slowly transform to the polymorphs of RTV (in days), Form I and finally Form II. Amorphous RTV in aqueous suspension also undergoes a transformation to a mesophase of similar morphology. Transformation pathways are consistent with measured dissolution rates and solubilities: amorphous > LLC >> Form I > Form II. The dissolution and solubility of LLC is slightly lower than that of the amorphous phase and about 20 times higher than that of Form II. RTV also self-assembles at the air/water interface as indicated by the decrease in surface tension of aqueous solutions. This behavior is similar to that of amphiphilic molecules that induce LLC formation.

  4. Application of various water soluble polymers in gas hydrate inhibition

    DEFF Research Database (Denmark)

    Kamal, Muhammad Shahzad; Hussein, Ibnelwaleed A.; Sultan, Abdullah S.

    2016-01-01

    . This review presents the various types of water soluble polymers used for hydrate inhibition, including conventional and novel polymeric inhibitors along with their limitations. The review covers the relevant properties of vinyl lactam, amide, dendrimeric, fluorinated, and natural biodegradable polymers....... The factors affecting the performance of these polymers and the structure-property relationships are reviewed. A comprehensive review of the techniques used to evaluate the performance of the polymeric inhibitors is given. This review also addresses recent developments, current and future challenges...

  5. Solubility of solid ferrocene in pressurized hot water

    Czech Academy of Sciences Publication Activity Database

    Karásek, Pavel; Hohnová, Barbora; Planeta, Josef; Roth, Michal

    2010-01-01

    Roč. 55, č. 8 (2010), s. 2866-2869 ISSN 0021-9568 R&D Projects: GA ČR GA203/07/0886; GA ČR GA203/08/1465; GA ČR GA203/08/1536 Institutional research plan: CEZ:AV0Z40310501 Keywords : pressurized hot water * ferrocene * solubility Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.089, year: 2010

  6. Extraction vitamins of group B water-soluble polymers

    Directory of Open Access Journals (Sweden)

    Y. I. Korenman

    2012-01-01

    Full Text Available General lows of extraction of B vitamins in aquatic environments of the solution of polymers (poly-N-vinylpyrrolidone, poly-N-vinilkaprolaktam has been studied. The influence of polymer concentration and structure on the distribution coefficients and degree of extraction of vitamins has been established. As a result, the direct search of a stable two-phase systems based on water-soluble polymers has been developed effective systems for the extraction of vitamin B from aqueous salt solutions.

  7. Water soluble vitamins and peritoneal dialysis - State of the art.

    Science.gov (United States)

    Jankowska, Magdalena; Lichodziejewska-Niemierko, Monika; Rutkowski, Bolesław; Dębska-Ślizień, Alicja; Małgorzewicz, Sylwia

    2017-12-01

    This review presents the results of a systematic literature search concerning water soluble vitamins and peritoneal dialysis modality. We provide an overview of the data available on vitamin requirements, dietary intake, dialysis related losses, metabolism and the benefits of supplementation. We also summarise the current recommendations concerning the supplementation of vitamins in peritoneal dialysis and discuss the safety of an administration of vitamins in pharmacological doses. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  8. Solubilities of oxygenated aromatic solids in pressurized hot water

    Czech Academy of Sciences Publication Activity Database

    Karásek, Pavel; Planeta, Josef; Roth, Michal

    2009-01-01

    Roč. 54, č. 5 (2009), s. 1457-1461 ISSN 0021-9568 R&D Projects: GA ČR GA203/07/0886; GA ČR GA203/08/1536 Institutional research plan: CEZ:AV0Z40310501 Keywords : oxygenated aromatics * solubility * pressurized hot water Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.695, year: 2009

  9. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S.; Debapriya, M. [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India); Nagaraja, V. [Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560012 (India); Raichur, Ashok M., E-mail: amr@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012 (India)

    2011-03-12

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO{sub 3} particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  10. Polyelectrolyte microcapsules for sustained delivery of water-soluble drugs

    International Nuclear Information System (INIS)

    Anandhakumar, S.; Debapriya, M.; Nagaraja, V.; Raichur, Ashok M.

    2011-01-01

    Polyelectrolyte capsules composed of weak polyelectrolytes are introduced as a simple and efficient system for spontaneous encapsulation of low molecular weight water-soluble drugs. Polyelectrolyte capsules were prepared by layer-by-layer (LbL) assembling of weak polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) on polystyrene sulfonate (PSS) doped CaCO 3 particles followed by core removal with ethylene-diaminetetraacetic acid (EDTA). The loading process was observed by confocal laser scanning microscopy (CLSM) using tetramethylrhodamineisothiocyanate labeled dextran (TRITC-dextran) as a fluorescent probe. The intensity of fluorescent probe inside the capsule decreased with increase in cross-linking time. Ciprofloxacin hydrochloride (a model water-soluble drug) was spontaneously deposited into PAH/PMA capsules and their morphological changes were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The quantitative study of drug loading was also elucidated which showed that drug loading increased with initial drug concentration, but decreased with increase in pH. The loaded drug was released in a sustained manner for 6 h, which could be further extended by cross-linking the capsule wall. The released drug showed significant antibacterial activity against E. coli. These findings indicate that such capsules can be potential carriers for water-soluble drugs in sustained/controlled drug delivery applications.

  11. 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...

  12. Effect of surfactants on the fluorescence spectra of water-soluble ...

    Indian Academy of Sciences (India)

    TECS

    Effect of surfactants on the fluorescence spectra of water-soluble. MEHPPV ... polyacrylic acid (PAA) chains grafted onto their backbone were found to be water soluble, and they exhi- ..... in other words the variation of emission intensity.

  13. Visualizing monolayers with a water-soluble fluorophore to quantify adsorption, desorption, and the double layer.

    Science.gov (United States)

    Shieh, Ian C; Zasadzinski, Joseph A

    2015-02-24

    Contrast in confocal microscopy of phase-separated monolayers at the air-water interface can be generated by the selective adsorption of water-soluble fluorescent dyes to disordered monolayer phases. Optical sectioning minimizes the fluorescence signal from the subphase, whereas convolution of the measured point spread function with a simple box model of the interface provides quantitative assessment of the excess dye concentration associated with the monolayer. Coexisting liquid-expanded, liquid-condensed, and gas phases could be visualized due to differential dye adsorption in the liquid-expanded and gas phases. Dye preferentially adsorbed to the liquid-disordered phase during immiscible liquid-liquid phase coexistence, and the contrast persisted through the critical point as shown by characteristic circle-to-stripe shape transitions. The measured dye concentration in the disordered phase depended on the phase composition and surface pressure, and the dye was expelled from the film at the end of coexistence. The excess concentration of a cationic dye within the double layer adjacent to an anionic phospholipid monolayer was quantified as a function of subphase ionic strength, and the changes in measured excess agreed with those predicted by the mean-field Gouy-Chapman equations. This provided a rapid and noninvasive optical method of measuring the fractional dissociation of lipid headgroups and the monolayer surface potential.

  14. Le Chatelier's Principle: The Effect of Temperature on the Solubility of Solids in Liquids.

    Science.gov (United States)

    Brice, L. K.

    1983-01-01

    Provides a rigorous but straightforward thermodynamic treatment of the temperature dependence of the solubility of solids in liquids that is suitable for presentation to undergraduates, suggesting how to approach the qualitative aspects of the subject for freshmen. Considers unsolvated/solvated solutes and Le Chatelier's principle. (JN)

  15. Solubility of carbon dioxide in the low-viscosity ionic liquid 1-hexyl-3-methylimidazolium tetracyanoborate

    NARCIS (Netherlands)

    Mota Martinez, M.T.; Althuluth, M.A.M.; Kroon, M.C.; Peters, C.J.

    2012-01-01

    The solubility of carbon dioxide (CO2) in a new low-viscosity and non-fluorinated ionic liquid, 1-hexyl-3-methylimidazolium tetracyanoborate ([hmim][TCB]), has been studied experimentally using a synthetic method. Bubble point pressures (up to 12.34 MPa) of the system CO2 + [hmim][TCB] are reported

  16. Single-laboratory validation of a high-performance liquid chromatographic-diode array detector-fluorescence detector/mass spectrometric method for simultaneous determination of water-soluble vitamins in multivitamin dietary tablets.

    Science.gov (United States)

    Chen, Pei; Atkinson, Renata; Wolf, Wayne R

    2009-01-01

    The purpose of this study was to develop a single-laboratory validated (SLV) method using high-performance liquid chromatography with different detectors [diode array detector (DAD); fluorescence detector (FLD); and mass spectrometry (MS)] for determination of 7 B-complex vitamins (B1-thiamin, B2-riboflavin, B3-nicotinamide, B6-pyridoxine, B9-folic acid, pantothenic acid, and biotin) and vitamin C in multivitamin/multimineral dietary supplements. The method involves the use of a reversed-phase octadecylsilyl column (4 microm, 250 x 2.0 mm id) and a gradient mobile phase profile. Gradient elution was performed at a flow rate of 0.25 mL/min. After a 5 min isocratic elution at 100% A (0.1% formic acid in water), a linear gradient to 50% A and 50% B (0.1% formic acid in acetonitrile) at 15 min was employed. Detection was performed with a DAD as well as either an FLD or a triple-quadrupole MS detector in the multiple reaction monitoring mode. SLV was performed using Standard Reference Material (SRM) 3280 Multivitamin/Multimineral Tablets, being developed by the National Institute of Standards and Technology, with support by the Office of Dietary Supplements of the National Institutes of Health. Phosphate buffer (10 mM, pH 2.0) extracts of the NIST SRM 3280 were analyzed by the liquid chromatographic (LC)-DAD-FLDIMS method. Following extraction, the method does not require any sample cleanup/preconcentration steps except centrifugation and filtration.

  17. Lipid nanoparticles for administration of poorly water soluble neuroactive drugs.

    Science.gov (United States)

    Esposito, Elisabetta; Drechsler, Markus; Mariani, Paolo; Carducci, Federica; Servadio, Michela; Melancia, Francesca; Ratano, Patrizia; Campolongo, Patrizia; Trezza, Viviana; Cortesi, Rita; Nastruzzi, Claudio

    2017-09-01

    This study describes the potential of solid lipid nanoparticles and nanostructured lipid carriers as nano-formulations to administer to the central nervous system poorly water soluble drugs. Different neuroactive drugs, i.e. dimethylfumarate, retinyl palmitate, progesterone and the endocannabinoid hydrolysis inhibitor URB597 have been studied. Lipid nanoparticles constituted of tristearin or tristearin in association with gliceryl monoolein were produced. The nanoencapsulation strategy allowed to obtain biocompatible and non-toxic vehicles, able to increase the solubility of the considered neuroactive drugs. To improve URB597 targeting to the brain, stealth nanoparticles were produced modifying the SLN surface with polysorbate 80. A behavioural study was conducted in rats to test the ability of SLN containing URB597 given by intranasal administration to alter behaviours relevant to psychiatric disorders. URB597 maintained its activity after nanoencapsulation, suggesting the possibility to propose this kind of vehicle as alternative to unphysiological mixtures usually employed for animal and clinical studies.

  18. Formulation of poorly water-soluble Gemfibrozil applying power ultrasound.

    Science.gov (United States)

    Ambrus, R; Naghipour Amirzadi, N; Aigner, Z; Szabó-Révész, P

    2012-03-01

    The dissolution properties of a drug and its release from the dosage form have a basic impact on its bioavailability. Solubility problems are a major challenge for the pharmaceutical industry as concerns the development of new pharmaceutical products. Formulation problems may possibly be overcome by modification of particle size and morphology. The application of power ultrasound is a novel possibility in drug formulation. This article reports on solvent diffusion and melt emulsification, as new methods supplemented with drying in the field of sonocrystallization of poorly water-soluble Gemfibrozil. During thermoanalytical characterization, a modified structure was detected. The specific surface area of the drug was increased following particle size reduction and the poor wettability properties could also be improved. The dissolution rate was therefore significantly increased. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Wintertime water-soluble aerosol composition and particle water content in Fresno, California

    Science.gov (United States)

    Parworth, Caroline L.; Young, Dominique E.; Kim, Hwajin; Zhang, Xiaolu; Cappa, Christopher D.; Collier, Sonya; Zhang, Qi

    2017-03-01

    The composition and concentrations of water-soluble gases and ionic aerosol components were measured from January to February 2013 in Fresno, CA, with a particle-into-liquid sampler with ion chromatography and annular denuders. The average (±1σ) ionic aerosol mass concentration was 15.0 (±9.4) µg m-3, and dominated by nitrate (61%), followed by ammonium, sulfate, chloride, potassium, nitrite, and sodium. Aerosol-phase organic acids, including formate and glycolate, and amines including methylaminium, triethanolaminium, ethanolaminium, dimethylaminium, and ethylaminium were also detected. Although the dominant species all came from secondary aerosol formation, there were primary sources of ionic aerosols as well, including biomass burning for potassium and glycolate, sea spray for sodium, chloride, and dimethylamine, and vehicles for formate. Particulate methanesulfonic acid was also detected and mainly associated with terrestrial sources. On average, the molar concentration of ammonia was 49 times greater than nitric acid, indicating that ammonium nitrate formation was limited by nitric acid availability. Particle water was calculated based on the Extended Aerosol Inorganics Model (E-AIM) thermodynamic prediction of inorganic particle water and κ-Köhler theory approximation of organic particle water. The average (±1σ) particle water concentration was 19.2 (±18.6) µg m-3, of which 90% was attributed to inorganic species. The fractional contribution of particle water to total fine particle mass averaged at 36% during this study and was greatest during early morning and night and least during the day. Based on aqueous-phase concentrations of ions calculated by using E-AIM, the average (±1σ) pH of particles in Fresno during the winter was estimated to be 4.2 (±0.2).

  20. Solubility of Aragonite in Subduction Water-Rich Fluids

    Science.gov (United States)

    Daniel, I.; Facq, S.; Petitgirard, S.; Cardon, H.; Sverjensky, D. A.

    2017-12-01

    Carbonate dissolution in subduction zone fluids is critical to the carbon budget in subduction zones. Depending on the solubility of carbonate minerals in aqueous fluids, the subducting lithosphere may be either strongly depleted and the mantle metasomatized if the solubility is high, as recently suggested by natural samples or transport carbon deeper into the Earth's mantle if the solubility is low enough [1, 2]. Dissolution of carbonate minerals strongly depends on pressure and temperature as well as on the chemistry of the fluid, leading to a highly variable speciation of aqueous carbon. Thanks to recent advances in theoretical aqueous geochemistry [3, 4], combined experimental and theoretical efforts now allow the investigation of speciation and solubility of carbonate minerals in aqueous fluids at PT conditions higher than previously feasible [4, 5]. In this study, we present new in situ X-ray fluorescence measurements of aragonite dissolution up to 5 GPa and 500°C and the subsequent thermodynamic model of aragonite solubility in aqueous fluids thanks to the Deep Earth Water model. The amount of dissolved aragonite in the fluid was calculated from challenging and unprecedented measurements of the Ca fluorescence K-lines at low-energy. Experiments were performed at the ESRF, beamline ID27 using a dedicated design of an externally-heated diamond anvil cell and an incident high-flux and highly focused monochromatic X-Ray beam at 20 keV. The results show a spectacularly high solubility of aragonite at HP-HT in water, further enhanced in presence of NaCl and silica in the solution. [1] Frezzotti, M. L. et al. (2011) doi:10.1038/ngeo1246. [2] Ague, J. J. and Nicolescu, S. (2014) doi:10.1038/ngeo2143. [3] Pan, D. et al. (2013) doi: 10.1073/pnas.1221581110. [4] Sverjensky, D. A et al. (2014) doi: 10.1016/j.gca.2013.12.019. [5] Facq, S. et al. (2014) doi: 10.1016/j.gca.2014.01.030.

  1. Leaching due to hygroscopic water uptake in cemented waste containing soluble salts

    DEFF Research Database (Denmark)

    Brodersen, K.

    1992-01-01

    conditions, condensation of water vapour will result in generation of a certain amount of liquid in the form of a strong salt solution. The volume of liquid may well exceed the storage capacity of the pore system in the cemented material and in the release of a limited amount of free contaminated solution......Considerable amounts of easily soluble salts such as sodium nitrate, sulphate, or carbonate are introduced into certain types of cemented waste. When such materials are stored in atmospheres with high relative humidity or disposed or by shallow land burial under unsaturated, but still humid....... A model of the quantitative aspects for the equilibrium situation is presented. Experiments with hygroscopic water uptake support the model and give indications about the rate of the process. The release mechanism is only thought to be important for radionuclides which are not fixed in a low...

  2. Ionic liquid-assisted solublization for improved enzymatic esterification of phenolic acids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    2012-01-01

    in a binary system, which is composed of ionic liquid tOMA•TFA (trioctylmethylammonium Trifluoroacetate) and octanol. Ionic liquid tOMA•TFA has great solubility towards most of phenolic acid. The strategy of increasing the solubility of phenolic in ionic liquid tOMA•TFA was proved to be an efficient way...... for increasing conversion of phenolic acids. The mixture ratio between tOMA•TFA and octanol was varied from 1:4 to 1:16 (v/v), it was found that the highest conversion of dihydrocaffeic acid (DHCA) was achieved when tOMA•TFA and octanol was mixed as 1:12 (v/v). It was also found that conversion of DHCA at 70 o...

  3. Changes in the content of water-soluble vitamins in Actinidia chinensis during cold storage

    Directory of Open Access Journals (Sweden)

    Zhu Xian-Bo

    2016-01-01

    Full Text Available We assessed the effects of cold storage on nine water-soluble vitamins in 7 cultivars of Actinidia chinensis (kiwifruit using high-performance liquid chromatography. Samples were collected at three time points during cold storage: one day, 30 days, and when edible. We found that vitamin C in most cultivars was raised with cold storage, but there was no consistent increased or decreased trend for other water-soluble vitamins across cultivars in storage. After one day of cold storage, vitamins B1 and B2 were the most prevalent vitamins in Control (wild fruit, while vitamins B5 and B6 were most prevalent in the Hongyang and Qihong cultivars. However, B12 was the most prevalent vitamin in the Qihong cultivar after 30 days of cold storage. Vitamins B3, B7, B9, and C were detected at the edible time point in Huayou, Hongyang, Jinnong-2, and Control fruit. Vitamin contents varied significantly among cultivars of kiwifruit following different durations of cold storage. Out of the three durations tested, a period of 30 days in cold storage was the most suitable for the absorption of water-soluble vitamins by A. chinensis.

  4. Liquid scintillator mixable with water

    International Nuclear Information System (INIS)

    Benson, R.H.

    1976-01-01

    A liquid scintillator mixable with water is described consisting of an aromatic solvent (xylene), a scintillation material and an ethoxylated alkyl phenol (as surface-active substance). So far such kinds of system have not given good measurements on counting samples with high water content. Due to the invention's composition one gets good results even with counting samples having a water content of over 30% if the alkyl substituent of the alkyl phenol contains 7, 10, 11, 13, 14, 15 or 16 C atoms and the ratio n/x of the number n of C atoms of the alkyl substituents to the average number x of the ethoxy groups of the ethoxylated alkyl phenols lie between 0.83 and 1.67. The following alkyl phenols are mentioned: heptyl phenol (n/x between 0.83 and 1.08), decyl phenol (n/x between 0.90 and 1.17), hendecyl phenol (n/x between 0.93 and 1.22), tridecyl phenol (n/x between 0.97 and 1.34), tetradecyl phenol (n/x between 1.08 and 1.55), pentadecyl phenol (n/x between 1.15 and 1.67), hexadecyl phenol (n/x between 1.33 and 1.51). (UWI) [de

  5. Chelating water-soluble polymers for waste minimization

    International Nuclear Information System (INIS)

    Smith, B.; Cournoyer, M.; Duran, B.; Ford, D.; Gibson, R.; Lin, M.; Meck, A.; Robinson, P.; Robison, T.

    1996-01-01

    Within the DOE complex and in industry there is a tremendous need for advanced metal ion recovery and waste minimization techniques. This project sought to employ capabilities for ligand-design and separations chemistry in which one can develop and evaluate water- soluble chelating polymers for recovering actinides and toxic metals from various process streams. Focus of this work was (1) to develop and select a set of water-soluble polymers suitable for a selected waste stream and (2) demonstrate this technology in 2 areas: removal of (a) actinides and toxic RCRA metals from waste water and (b) recovery of Cu and other precious metals from industrial process streams including from solid catalysts and aqueous waste streams. The R ampersand D was done in 4 phases for each of the 2 target areas: polymer synthesis for scaleup, equipment assembly, process demonstration at a DOE or industrial site, and advanced ligand/polymer synthesis. The TA- 50 site at Los Alamos was thought to be appropriate due to logistics and to its being representative of similar problems throughout the DOE complex

  6. 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.

  7. Solubility of root-canal sealers in water and artificial saliva.

    Science.gov (United States)

    Schäfer, E; Zandbiglari, T

    2003-10-01

    To compare the weight loss of eight different root-canal sealers in water and in artificial saliva with different pH values. For standardized samples (n = 12 per group), ring moulds were filled with epoxy resin (AH 26, AH Plus)-, silicone (RSA RoekoSeal)-, calcium hydroxide (Apexit, Sealapex)-, zinc oxide-eugenol (Aptal-Harz)-, glass-ionomer (Ketac Endo)- and polyketone (Diaket)-based sealers. These samples were immersed in double-distilled water or artificial saliva with different pH values (7.0, 5.7 and 4.5) for 30 s, 1 min, 2 min, 5 min, 10 min, 20 min, 1 h, 2 h, 10 h, 24 h, 48 h, 72 h, 14 days and 28 days. Mean loss of weight was determined and analysed statistically using a one-way anova and Student-Newman-Keuls test for all pairwise comparisons. Most sealers were of low solubility, although Sealapex, Aptal-Harz and Ketac Endo showed a marked weight loss in all liquids. Even after 28 days of storage in water, AH 26, AH Plus, RSA RoekoSeal, and Diaket showed less than 3% weight loss. At exposure times greater than 14 days, Sealapex showed the significantly greatest weight loss of all sealers tested (P < 0.05). Aptal-Harz and Ketac Endo were significantly more soluble in saliva (pH 4.5) than in water (P < 0.05). Under the conditions of the present study, AH Plus showed the least weight loss of all sealers tested, independent of the solubility medium used. Sealapex, Aptal-Harz and Ketac Endo had a marked weight loss in all liquids.

  8. Effect of carbon and silicon on nitrogen solubility in liquid chromium and iron-chromium alloys

    International Nuclear Information System (INIS)

    Khyakkinen, V.I.; Bezobrazov, S.V.

    1986-01-01

    The study is aimed at specifying the role of carbon and silicon in high-chromium melts nitridation processes. It is shown that in high-chromium melts of the Cr-Fe-C system the nitrogen solubility is reduced with the growth of carbon content and in the chromium concentration range of 70-100% at 1873 K and P N 2 =0.1 MPa it is described by the lg[%N] Cr-Fe-C =lg[%N] cr-fe -0.098[%C] equation. While decreasing the temperature the nitrogen solubility in alloys is increased. Silicon essentially decreases the nitrogen solubility in liquid chromium. For the 0-10% silicon concentration range the relation between the equilibrium content of nitrogen and silicon at 1873 K and P N 2 =0.1 MPa is described by the straight line equation [%N] Cr-Si =6.1-0.338 [%Si

  9. Biological properties of water-soluble phosphorhydrazone dendrimers

    Directory of Open Access Journals (Sweden)

    Anne-Marie Caminade

    2013-01-01

    Full Text Available Dendrimers are hyperbranched and perfectly defined macromolecules, constituted of branches emanating from a central core in an iterative fashion. Phosphorhydrazone dendrimers constitute a special family of dendrimers, possessing one phosphorus atom at each branching point. The internal structure of these dendrimers is hydrophobic, but hydrophilic terminal groups can induce the solubility of the whole structure in water. Indeed, the properties of these compounds are mainly driven by the type of terminal groups their bear; this is especially true for the biological properties. For instance, positively charged terminal groups are efficient for transfection experiments, as drug carriers, as anti-prion agents, and as inhibitor of the aggregation of Alzheimer's peptides, whereas negatively charged dendrimers have anti-HIV properties and can influence the human immune system, leading to anti-inflammatory properties usable against rheumatoid arthritis. This review will give the most representative examples of the biological properties of water-soluble phosphorhydrazone dendrimers, organized depending on the type of terminal groups they bear.

  10. Solubility of Methane, Ethane, and Propane in Pure Water Using New Binary Interaction Parameters

    Directory of Open Access Journals (Sweden)

    Masoud Behrouz

    2015-07-01

    Full Text Available Solubility of hydrocarbons in water is important due to ecological concerns and new restrictions on the existence of organic pollutants in water streams. Also, the creation of a thermodynamic model has required an advanced study of the phase equilibrium between water (as a basis for the widest spread muds and amines and gas hydrocarbon phases in wide temperature and pressure ranges. Therefore, it is of great interest to develop semi-empirical correlations, charts, or thermodynamic models for estimating the solubility of hydrocarbons in liquid water. In this work, a thermodynamic model based on Mathias modification of Sova-Redlich-Kwong (SRK equation of state is suggested using classical mixing rules with new binary interaction parameters which were used for two-component systems of hydrocarbons and water. Finally, the model results and their deviations in comparison with the experimental data are presented; these deviations were equal to 5.27, 6.06, and 4.1% for methane, ethane, and propane respectively.

  11. Oil-soluble and water-soluble BTPhens and their europium complexes in octanol/water solutions: interface crossing studied by MD and PMF simulations.

    Science.gov (United States)

    Benay, G; Wipff, G

    2013-01-31

    Bistriazinyl-phenantroline "BTPhen" ligands L display the remarkable feature to complex trivalent lanthanide and actinide ions, with a marked selectivity for the latter. We report on molecular dynamics studies of tetrasubstituted X(4)BTPhens: L(4+) (X = (+)Et(3)NCH(2)-), L(4-) (X = (-)SO(3)Ph-), and L(0) (X = CyMe(4)) and their complexes with Eu(III) in binary octanol/water solutions. Changes in free energies upon interface crossing are also calculated for typical solutes by potential of mean force PMF simulations. The ligands and their complexes partition, as expected, to either the aqueous or the oil phase, depending on the "solubilizing" group X. Furthermore, most of them are found to be surface active. The water-soluble L(4+) and L(4-) ligands and their (L)Eu(NO(3))(3) complexes adsorb at the aqueous side of the interface, more with L(4-) than with L(4+). The oil soluble ligand L(0) is not surface active in its endo-endo form but adsorbs on the oil side of the interface in its most polar endo-exo form, as well as in its protonated L(0)H(+) and complexed (L(0))Eu(NO(3))(3) states. Furthermore, comparing PMFs of the Eu(III) complexes with and without nitric acid shows that acidifying the aqueous phase has different effects, depending on the ligand charge. In particular, acid promotes the Eu(III) extraction by L(0) via the (L(0))(2)Eu(NO(3))(2+) complex, as observed experimentally. Overall, the results point to the importance of interfacial adsorption for the liquid-liquid extraction of trivalent lanthanide and actinide cations by BTPhens and analogues.

  12. Solubilities of gases in ionic liquids using a corresponding-states approach to Kirkwood-Buff solution theory

    DEFF Research Database (Denmark)

    Ellegaard, Martin Dela; Abildskov, Jens; O’Connell, John P.

    2011-01-01

    The solubilities of gases in ionic liquids and compressed liquid densities have been successfully described over a wide range of conditions using a reformulated corresponding-states formulation for direct correlation function integrals. In addition, comparisons with experimental data show reliabl...... prediction of ionic liquid characteristic properties from simple rules.......The solubilities of gases in ionic liquids and compressed liquid densities have been successfully described over a wide range of conditions using a reformulated corresponding-states formulation for direct correlation function integrals. In addition, comparisons with experimental data show reliable...

  13. Facile synthesis of water-soluble curcumin nanocrystals

    Directory of Open Access Journals (Sweden)

    Marković Zoran M.

    2015-01-01

    Full Text Available In this paper, facile synthesis of water soluble curcumin nanocrystals is reported. Solvent exchange method was applied to synthesize curcumin nanocrystals. Different techniques were used to characterize the structural and photophysical properties of curcumin nanocrystals. We found that nanocurcumin prepared by this method had good chemical and physical stability, could be stored in the powder form at room temperature, and was freely dispersible in water. It was established that the size of curcumin nanocrystals was varied in the range of 20-500 nm. Fourier transform infrared spectroscopy and UV-Vis analyses showed the presence of tetrahydrofuran inside the curcumin nanocrystals. Also, it was found that nanocurcumin emitted photoluminescencewith yellow-green colour. [Projekat Ministarstva nauke Republike Srbije, br. 172003

  14. Water tube liquid metal control

    International Nuclear Information System (INIS)

    Campbell, J.W.E.

    1981-01-01

    An improved heat exchanger for use in liquid metal cooled nuclear power reactors is described in which the heat is transferred between the flow of liquid metal which is to be cooled and a forced flow of liquid which is wholly or partly evaporated. (U.K.)

  15. SOLUBILITY AND BIOAVAILABILITY ENHANCEMENT STRATEGIES FOR EFFECTIVE DELIVERY OF POORLY WATER SOLUBLE DRUGS BY NANO FORMULATIONS AND SOLID DISPERSIONS

    OpenAIRE

    Rayapolu Ranga Goud*, Gunnala Krishnaveni, Girija Prasad Patro

    2018-01-01

    For the ancient few years, there has been a substantial research done on diverse methodologies for poorly water soluble and lipophilic drugs. More in modern times voluminous molecules cannot be distributed due to low solubility. Now a day frequently, particulate vesicle systems such as nanoparticles, liposomes, microspheres, niosomes, pronisomes, ethosomes, and proliposomes have been used as drug carriers. Drug delivery designates the technique and methodology to conveying medications or drug...

  16. Use of tritium to predict soluble pollutants transport in Ebro River waters (Spain).

    Science.gov (United States)

    Pujol, L; Sanchez-Cabeza, J A

    2000-05-01

    The Ebro River, in Northeast Spain, discharges into the Mediterranean Sea after flowing through several large cities and agricultural, mining and industrial areas. The Ascó nuclear power plant (NPP) is located in its lower section and comprises two pressurised water reactor units, from which low-level liquid radioactive waste is released to river waters under authority control. Tritium routinely released by the NPP was used as a radiotracer to determine the longitudinal dispersion coefficient and velocity of the river waters. Several field experiments, in co-ordination with the NPP, were carried out during 1991 and 1992. During each field experiment, the flow rate was kept constant by dams located upstream from the NPP. After each tritium release, water was sampled downstream at periodic intervals over several hours and tritium was measured with a low-background liquid scintillation counter. Velocity and dispersion coefficient were determined in river waters for several river discharges using an analytical, box-type and numerical approach to solve the one-dimensional advection-diffusion equation. The set of calibrated parameters was used to predict the displacement and dispersion of soluble pollutants in river waters. Velocity was determined as a function of river discharge and river slope, and dispersion coefficient was determined as a function of distance. Finally, sensitivity of the model predictions was studied and uncertainties of the fitted parameters were estimated.

  17. Water-soluble resist for environmentally friendly lithography

    Science.gov (United States)

    Lin, Qinghuang; Simpson, Logan L.; Steinhaeusler, Thomas; Wilder, Michelle; Willson, C. Grant; Havard, Jennifer M.; Frechet, Jean M. J.

    1996-05-01

    This paper describes an 'environmentally friendly,' water castable, water developable photoresist system. The chemically amplified negative-tone resist system consists of three water-soluble components: a polymer, poly(methyl acrylamidoglycolate methyl ether), [poly(MAGME)]; a photoacid generator, dimethyl dihydroxyphenylsulfonium triflate and a crosslinker, butanediol. Poly(MAGME) was synthesized by solution free radical polymerization. In the three-component resist system, the acid generated by photolysis of the photoacid generator catalyzes the crosslinking of poly(MAGME) in the exposed regions during post-exposure baking, thus rendering the exposed regions insoluble in water. Negative tone relief images are obtained by developing with pure water. The resist is able to resolve 1 micrometer line/space features (1:1 aspect ratio) with an exposure dose of 100 mJ/cm2 at 248 nm. The resist can be used to generate etched copper relief images on printed circuit boards using aqueous sodium persulfate as the etchant. The crosslinking mechanism has been investigated by model compound studies using 13C NMR. These studies have revealed that the acid catalyzed reaction of the poly(MAGME) with butanediol proceeds via both transesterification and transacetalization (transaminalization) reactions at low temperatures, and also via transamidation at high temperatures.

  18. Monosaccharides as Versatile Units for Water-Soluble Supramolecular Polymers.

    Science.gov (United States)

    Leenders, Christianus M A; Jansen, Gijs; Frissen, Martijn M M; Lafleur, René P M; Voets, Ilja K; Palmans, Anja R A; Meijer, E W

    2016-03-18

    We introduce monosaccharides as versatile water-soluble units to compatibilise supramolecular polymers based on the benzene-1,3,5-tricarboxamide (BTA) moiety with water. A library of monosaccharide-based BTAs is evaluated, varying the length of the alkyl chain (hexyl, octyl, decyl and dodecyl) separating the BTA and saccharide units, as well as the saccharide units (α-glucose, β-glucose, α-mannose and α-galactose). In all cases, the monosaccharides impart excellent water compatibility. The length of the alkyl chain is the determining factor to obtain either long, one-dimensional supramolecular polymers (dodecyl spacer), small aggregates (decyl spacer) or molecularly dissolved (octyl and hexyl) BTAs in water. For the BTAs comprising a dodecyl spacer, our results suggest that a cooperative self-assembly process is operative and that the introduction of different monosaccharides does not significantly change the self- assembly behaviour. Finally, we investigate the potential of post-assembly functionalisation of the formed supramolecular polymers by taking advantage of dynamic covalent bond formation between the monosaccharides and benzoxaboroles. We observe that the supramolecular polymers readily react with a fluorescent benzoxaborole derivative permitting imaging of these dynamic complexes by confocal fluorescence microscopy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Evaluating the Liquid Liquid Phase Transition Hypothesis of Supercoooled Water

    Science.gov (United States)

    Limmer, David; Chandler, David

    2011-03-01

    To explain the anomalous behavior of supercooled water it has been conjectured that buried within an experimentally inaccessible region of liquid water's phase diagram there exists a second critical point, which is the terminus of a first order transition line between two distinct liquid phases. The so-called liquid-liquid phase transition (LLPT) has since generated much study, though to date there is no consensus on its existence. In this talk, we will discuss our efforts to systematically study the metastable phase diagram of supercooled water through computer simulation. By employing importance-sampling techniques, we have calculated free energies as a function of the density and long-range order to determine unambiguously if two distinct liquid phases exist. We will argue that, contrary to the LLPT hypothesis, the observed phenomenology can be understood as a consequence of the limit of stability of the liquid far away from coexistence. Our results suggest that homogeneous nucleation is the cause of the increased fluctuations present upon supercooling. Further we will show how this understanding can be extended to explain experimental observations of hysteresis in confined supercooled water systems.

  20. Electrokinetic Power Generation from Liquid Water Microjets

    Energy Technology Data Exchange (ETDEWEB)

    Duffin, Andrew M.; Saykally, Richard J.

    2008-02-15

    Although electrokinetic effects are not new, only recently have they been investigated for possible use in energy conversion devices. We have recently reported the electrokinetic generation of molecular hydrogen from rapidly flowing liquid water microjets [Duffin et al. JPCC 2007, 111, 12031]. Here, we describe the use of liquid water microjets for direct conversion of electrokinetic energy to electrical power. Previous studies of electrokinetic power production have reported low efficiencies ({approx}3%), limited by back conduction of ions at the surface and in the bulk liquid. Liquid microjets eliminate energy dissipation due to back conduction and, measuring only at the jet target, yield conversion efficiencies exceeding 10%.

  1. Study to evaluate the impact of heat treatment on water soluble vitamins in milk.

    Science.gov (United States)

    Asadullah; Khair-un-nisa; Tarar, Omer Mukhtar; Ali, Syed Abdul; Jamil, Khalid; Begum, Askari

    2010-11-01

    To evaluate the effect of domestic boiling practice on the contents of water soluble vitamins of loose milk and quantitative comparison of these vitamins in Ultra High Temperature (UHT) treated packaged milk with that of boiled loose milk. Loose milk samples were collected from various localities of Karachi city (Pakistan). These samples were boiled in simulated household conditions for 5, 10 and 15 minutes. Ultra High Temperature (UHT) treated packaged milk samples of various brands were obtained from the local market. The aliquots were analyzed for water-soluble vitamins using High Performance Liquid Chromatography (HPLC) technique. The mean values and standard deviations for data were computed and compared as well as level of variations were also determined. Conventional boiling caused destruction of water soluble vitamins in milk i.e. vitamin 81 content in fresh milk decreased from 0.037 mg/100 g to 0.027 mg/100 g after 15 min boiling, whereas vitamin B2 from 0.115 to 0.084 mg/100 g, vitamin B3 0.062 to 0.044 mg/100 g, vitamin B6 0.025 to 0.019 mg/100 g and folic acid 3.38 to 2.40 microg/100 g. This accounted for a post-boiling decrease of about 27, 27, 29, 24 and 36% in vitamins B1, B2, B3, B6 and folic acid respectively. The values for vitamins B1, B2, B3, B6 and folic acid determined in boiled milk were significantly lower than UHT treated packaged milk samples by 25.9, 75.0, 54.5, 63.16 and 38.1% respectively. Conventional boiling caused drastic reduction in vitamin levels of loose milk samples. In comparison to this, UHT milk retained high levels of water soluble B-vitamins. Thus it could be envisaged that UHT treated milk provides better water soluble vitamins' nourishment than conventionally boiled milk (JPMA 60:909; 2010).

  2. Study to evaluate the impact of heat treatment on water soluble vitamins in milk

    International Nuclear Information System (INIS)

    Khair-un-Nisa, A.; Tarar, O.M.; Ali, S.A.; Jamil, K.; Begum, A.

    2010-01-01

    Objectives: To evaluate the effect of domestic boiling practice on the contents of water soluble vitamins of loose milk and quantitative comparison of these vitamins in Ultra High Temperature (UHT) treated packaged milk with that of boiled loose milk. Methods: Loose milk samples were collected from various localities of Karachi city (Pakistan). These samples were boiled in simulated household conditions for 5, 10 and 15 minutes. Ultra High Temperature (UHT) treated packaged milk samples of various brands were obtained from the local market. The aliquots were analyzed for water-soluble vitamins using High Performance Liquid Chromatography (HPLC) technique. The mean values and standard deviations for data were computed and compared as well as level of variations were also determined. Results: Conventional boiling caused destruction of water soluble vitamins in milk i.e. vitamin B1 content in fresh milk decreased from 0.037 mg/100g to 0.027 mg/100g after 15 min boiling, whereas vitamin B2 from 0.115 to 0.084 mg/100g, vitamin B3 0.062 to 0.044 mg/100g, vitamin B6 0.025 to 0.019 mg/100g and folic acid 3.38 to 2.40 < g/100g. This accounted for a post-boiling decrease of about 27, 27, 29, 24 and 36% in vitamins B1, B2, B3, B6 and folic acid respectively. The values for vitamins B1, B2, B3, B6 and folic acid determined in boiled milk were significantly lower than UHT treated packaged milk samples by 25.9, 75.0, 54.5, 63.16 and 38.1% respectively. Conclusion: Conventional boiling caused drastic reduction in vitamin levels of loose milk samples. In comparison to this, UHT milk retained high levels of water soluble B-vitamins. Thus it could be envisaged that UHT treated milk provides better water soluble vitamins' nourishment than conventionally boiled milk. (author)

  3. Electrochemical study on determination of diffusivity, activity and solubility of oxygen in liquid bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Rajesh [Liquid Metals and Structural Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Gnanasekaran, T. [Liquid Metals and Structural Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)]. E-mail: gnani@igcar.ernet.in; Srinivasa, Raman S. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400 076 (India)

    2006-06-15

    Diffusivity of oxygen in liquid bismuth was measured by potentiostatic method and is given bylg(D{sub O}{sup Bi}/cm{sup 2}.s{sup -1})(+/-0.042)=-3.706-1377/(TK{sup -1})(804liquid bismuth was derived for the reaction:1/2O{sub 2}(g)=[O]{sub Bi}(at.%)and is given by{delta}G{sub O(Bi)}{sup o}/(J.g-atomO{sup -1})(+/-720)=-108784+20.356TK{sup -1}(753solubility of oxygen in liquid bismuth was derived as a function of temperature and is given by the following expressions:lg(S/at%O)(+/-0.05)=-4476/TK{sup -1}+4.05(753solubility of oxygen in liquid bismuth is compared with the literature data.

  4. Determination and modeling of the solubility of (limonin in methanol or acetone + water) binary solvent mixtures at T = 283.2 K to 318.2 K

    International Nuclear Information System (INIS)

    Fan, Jie-Ping; Zheng, Bing; Liao, Dan-Dan; Yu, Jia-Xin; Cao, Ya-Hui; Zhang, Xue-Hong; Zhu, Jian-Hang

    2016-01-01

    Highlights: • The solubilities of limonin were measured in the binary solvent mixtures methanol + water and acetone + water. • The solubility data were correlated by nine models. • The solubility of limonin had a maximum point at 0.9 mol fraction of acetone in acetone + water mixtures. - Abstract: The solubility of limonin in the binary solvent mixtures (methanol + water) and (acetone + water) with various initial mole fractions of methanol or acetone was measured by high-performance liquid chromatography (HPLC) at different temperatures ranging from 283.2 K to 318.2 K. The solubility of limonin increased with increasing initial mole fraction of methanol in (methanol + water) mixtures, whereas it had a maximum point at 0.9 mol fraction of acetone in (acetone + water) mixtures. The solubility of limonin increased with increasing temperature in the two binary solvent mixtures. The solubility of limonin was correlated with temperature by the van’t Hoff model and the modified Apelblat model, and the fitting results showed that the modified Apelblat model had better correlation. The CNIBS/Redlich–Kister model and the simplified CNIBS/Redlich–Kister model were used to correlate the solubility data with the initial solvent composition, the results show that the CNIBS/Redlich–Kister model reveals better agreement with the experimental values. Furthermore, to illustrate the effects of both temperature and initial solvent composition on the changes in the solubility of limonin, the solubility values were fitted by the Jouyban–Acree, van’t Hoff–Jouyban–Acree, modified Apelblat–Jouyban–Acree, Ma and Sun models. Among the five models, the Jouyban–Acree model give the best correlation results for (methanol + water) binary solvent mixtures, while the experimental solubility in the (acetone + water) system was most accurately correlated by the van’t Hoff–Jouyban–Acree model.

  5. Catalytic hydrotreating of lignin with water-soluble molybdenum catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Osmaa, A.; Johansson, A. (Technical Research Centre of Finland, Espoo (Finland). Lab. of Fuel and Process Technology)

    High yields (61% of the original lignin) of low molecular weight oil (84% of the oil eluted through GC) have been obtained by hydrotreating kraft pine lignin with a water-soluble molybdenum catalyst at 430[degree]C for 60 min. The main compounds in the product oil were phenols (8.7% of the original lignin), cyclohexanes (5.0%), benzenes (3.8%), naphthalenes (4.0%), and phenanthrenes (1.2%). The degree of hydrodeoxygenation was 98%. The quality (measured by GPC and GC) of the product was as good as when using more expensive solid NiMo-CR[sub 2]O[sub 3] catalysts. 30 refs., 6 tabs.

  6. Lumbar myelography using water-soluble contrast media

    International Nuclear Information System (INIS)

    Langlotz, M.

    1981-01-01

    With the new water-soluble contrast media developed in the last 10 years, lumbar myelography has become a simple and low-risk diagnostic method of great value which is hardly ever omitted before surgery is undertaken. The book attempts a synopsis of radiology and clinical examinations. In its first part, the pathological, clinical, and radiological aspects of diseases of the lumbosacral spinal duct are reviewed. The second part contains more than 300 myelographic pictures in original size. Each of the myelograms is supplemented by the case history of the patient (anamnesis, neurological examination, therapy and course). Interpretation is facilitated by drawings at the beginning of each chapter which show the major pathological and radiological changes. (orig./MG) [de

  7. Novel water-soluble curcumin derivative mediating erectile signaling.

    Science.gov (United States)

    Abdel Aziz, Mohamed Talaat; El Asmer, Mohammed F; Rezq, Ameen; Kumosani, Taha Abdullah; Mostafa, Samya; Mostafa, Taymour; Atta, Hazem; Abdel Aziz Wassef, Mohamed; Fouad, Hanan H; Rashed, Laila; Sabry, Dina; Hassouna, Amira A; Senbel, Amira; Abdel Aziz, Ahmed

    2010-08-01

    Curcumin is an inducer of heme oxygenase enzyme-1 (HO-1) that is involved in erectile signaling via elevating cyclic guanosine monophosphate (cGMP)levels. To assess the effect of oral administration of a water-soluble long-acting curcumin derivative on erectile signaling. Two hundred and thirty six male white albino rats were divided into four groups; group 1 (N = 20) includes control. Group 2 (N = 72) was equally divided into four subgroups; subgroup 1 received pure curcumin (10 mg/kg), subgroup 2 received the long-acting curcumin derivative (2 mg/kg), subgroup 3 received the long-acting curcumin derivative (10 mg/kg), and subgroup 4 received sildenafil (4 mg/kg). Subgroups were sacrificed after the first, second, and third hour. Group 3 (N = 72) was equally divided into the same four subgroups already mentioned and were sacrificed after 24 hours, 48 hours, and 1 week. Group 4 (N = 72) was subjected to intracavernosal pressure (ICP) measurements 1 hour following oral administration of the same previous doses in the same rat subgroups. Cavernous tissue HO enzyme activity, cGMP, and ICP. In group 2, there was a significant progressive maintained elevation of HO activity and cGMP tissue levels starting from the first hour in subgroups 3 and 4, whereas, the rise in HO activity and cGMP started from second hour regarding the other rat subgroups. Sildenafil effect decreased after 3 hours. In group 3, there was a significant maintained elevation of HO activity and cGMP tissue levels extended to 1 week as compared to controls for all rat subgroups that received both forms of curcumin. In group 4, long-acting curcumin derivative exhibited more significant potentiation of intracavernosal pressure as compared to control and to the pure curcumin. Water-soluble long-acting curcumin derivative could mediate erectile function via upregulating cavernous tissue cGMP. © 2009 International Society for Sexual Medicine.

  8. Spectrofluorimetric determination of some water-soluble vitamins.

    Science.gov (United States)

    Mohamed, Abdel-Maaboud I; Mohamed, Horria A; Abdel-Latif, Niveen M; Mohamed, Marwa R

    2011-01-01

    Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding lambda(exc) or lambda(em). The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46-1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 +/- 0.7-101.2 +/- 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.

  9. CO2 Capture in Ionic Liquids: A Review of Solubilities and Experimental Methods

    Directory of Open Access Journals (Sweden)

    Elena Torralba-Calleja

    2013-01-01

    Full Text Available The growing concern of climate change and global warming has in turn given rise to a thriving research field dedicated to finding solutions. One particular area which has received considerable attention is the lowering of carbon dioxide emissions from large-scale sources, that is, fossil fuel power. This paper focuses on ionic liquids being used as novel media for CO2 capture. In particular, solubility data and experimental techniques are used at a laboratory scale. Cited CO2 absorption data for imidazolium-, pyrrolidinium-, pyridinium-, quaternary-ammonium-, and tetra-alkyl-phosphonium-based ionic liquids is reviewed, expressed as mole fractions (X of CO2 to ionic liquid. The following experimental techniques are featured: gravimetric analysis, the pressure drop method, and the view-cell method.

  10. Comment on "Spontaneous liquid-liquid phase separation of water"

    Science.gov (United States)

    Limmer, David T.; Chandler, David

    2015-01-01

    Yagasaki et al. [Phys. Rev. E 89, 020301 (2014), 10.1103/PhysRevE.89.020301] present results from a molecular dynamics trajectory illustrating coarsening of ice, which they interpret as evidence of transient coexistence between two distinct supercooled phases of liquid water. We point out that neither two distinct liquids nor criticality are demonstrated in this simulation study. Instead, the illustrated trajectory is consistent with coarsening behaviors analyzed and predicted in earlier work by others.

  11. Comment on "Spontaneous liquid-liquid phase separation of water".

    Science.gov (United States)

    Limmer, David T; Chandler, David

    2015-01-01

    Yagasaki et al. [Phys. Rev. E 89, 020301 (2014)] present results from a molecular dynamics trajectory illustrating coarsening of ice, which they interpret as evidence of transient coexistence between two distinct supercooled phases of liquid water. We point out that neither two distinct liquids nor criticality are demonstrated in this simulation study. Instead, the illustrated trajectory is consistent with coarsening behaviors analyzed and predicted in earlier work by others.

  12. Novel micellar systems for the formulation of poorly water soluble drugs : biocompatibility aspects and pharmaceutical applications

    OpenAIRE

    Dumontet Mondon, Karine

    2010-01-01

    Amongst the large number of novel drugs, 95% are lipophilic and poorly water soluble. Particularly, this renders their aqueous formulation very difficult. In this regard this thesis focused on polymeric micelles based on novel MPEG-hexPLA copolymers forming a hydrophilic shell and a very hydrophobic core that favors the incorporation of poorly water soluble drugs. Although the drug hydrophobicity and water solubility are the main parameters in respect to their incorporation efficiency, struct...

  13. Reactive liquid/liquid extraction of heavy metals from landfill seepage waters. Its characterisation and application

    International Nuclear Information System (INIS)

    Woller, N.

    1994-06-01

    This study demonstrates the applicability of liquid-liquid extraction by means of the commercial complexers LIX26 R and LIX84 R to heavy metal removal from waste waters. The composition of this oil-soluble complex is MeR 2 , where Me denotes Hg 2+ , Cd 2+ , Zn 2+ , Cu 2+ , and Ni 2+ , and R denotes LIX84 R . This composition makes the complex electrically neutral, and all polar groups are located inside the molecule. The extraction efficiency of the complexer LIX84 R for the various metal ions is evident in the succession Cu 2+ , Ni 2+ >> Zn 2+ > Hg 2+ > Cd 2+ . These heavy metal ions are even readily extractable at chloride concentrations of up to 1 mol/l. As the structure of the complexer is that of an oil-soluble surfactant with complexing properties, it accumulates at the phase boundary between oil and water. Measurement of interfacial tension in various solvent systems showed that the polar solvent chloroform permits only a weak accumulation of the complexer (400 nmol/m 2 ), whereas the unpolar solvent kerosine permits greater accumulation specifically on the water side of the phase boundary (1958 nmol/m 2 ). Organic solvents solvate the complexer so well, that it is even removed from the air side of the phase boundary. The differing accumulation of the complexer at the water/oil phase boundary explains the differing increase of phase separation time for polar and unpolar solvents. (orig.) [de

  14. Model evaluation for the prediction of solubility of active pharmaceutical ingredients (APIs to guide solid–liquid separator design

    Directory of Open Access Journals (Sweden)

    Kuveneshan Moodley

    2018-05-01

    Full Text Available The assumptions and models for solubility modelling or prediction in systems using non-polar solvents, or water and complex triterpene and other active pharmaceutical ingredients as solutes aren't well studied. Furthermore, the assumptions concerning heat capacity effects (negligibility, experimental values or approximations are explored, using non-polar solvents (benzene, or water as reference solvents, for systems with solute melting points in the range of 306–528 K and molecular weights in the range of 90–442 g/mol. New empirical estimation methods for the ΔfusCpi of APIs are presented which correlate the solute molecular masses and van der Waals surface areas with ΔfusCpi. Separate empirical parameters were required for oxygenated and non-oxygenated solutes. Subsequently, the predictive capabilities of the various approaches to solubility modelling for complex pharmaceuticals, for which data is limited, are analysed. The solute selection is based on a principal component analysis, considering molecular weights, fusion temperatures, and solubilities in a non-polar solvent, alcohol, and water, where data was available. New NRTL-SAC parameters were determined for selected steroids, by regression. The original UNIFAC, modified UNIFAC (Dortmund, COSMO-RS (OL, and COSMO-SAC activity coefficient predictions are then conducted, based on the availability of group constants and sigma profiles. These are undertaken to assess the predictive capabilities of these models when each assumption concerning heat capacity is employed. The predictive qualities of the models are assessed, based on the mean square deviation and provide guidelines for model selection, and assumptions concerning phase equilibrium, when designing solid–liquid separators for the pharmaceutical industry on process simulation software. The most suitable assumption regarding ΔfusCpi was found to be system specific, with modified UNIFAC (Dortmund performing well in benzene as

  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. Reaction of water vapor with a clean liquid uranium surface

    International Nuclear Information System (INIS)

    Siekhaus, W.

    1985-01-01

    To study the reaction of water vapor with uranium, we have exposed clean liquid uranium surfaces to H 2 O under UHV conditions. We have measured the surface concentration of oxygen as a function of exposure, and determined the maximum attainable surface oxygen concentration X 0 /sup s/ as a function of temperature. We have used these measurements to estimate, close to the melting point, the solubility of oxygen (X 0 /sup b/, -4 ) and its surface segregation coefficient β/sup s/(> 10 3 ). 8 refs., 5 figs., 1 tab

  17. Radioactive liquid water processing method

    International Nuclear Information System (INIS)

    Yasumura, Keijiro; Noda, Tetsuya; Kobayashi, Fumio.

    1993-01-01

    Alkaline earth metals and heavy metals are added to radioactive liquid wastes containing a surface active agent comprising alkali metal salts of higher fatty acids. These metals form metal soaps with the surface active agent dissolved in the liquid wastes and crystallized. The crystallized metal soaps are introduced to a filtering column filled with a burnable polymeric fibrous filtering material. The filtering material is burnt. This can remove the surface active agent to remove COD without using an active carbon. (T.M.)

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

    Directory of Open Access Journals (Sweden)

    Shailendra Singh Solanki

    2013-01-01

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

  19. Development of clinical dosage forms for a poorly water-soluble drug II: formulation and characterization of a novel solid microemulsion preconcentrate system for oral delivery of a poorly water-soluble drug.

    Science.gov (United States)

    Li, Ping; Hynes, Sara R; Haefele, Thomas F; Pudipeddi, Madhu; Royce, Alan E; Serajuddin, Abu T M

    2009-05-01

    The solution of a poorly water-soluble drug in a liquid lipid-surfactant mixture, which served as a microemulsion preconcentrate, was converted into a solid form by incorporating it in a solid polyethylene glycol (PEG) matrix. The solid microemulsion preconcentrates thus formed consisted of Capmul PG8 (propylene glycol monocaprylate) as oil, Cremophor EL (polyoxyl 35 castor oil) as surfactant, and hydrophilic polymer PEG 3350 as solid matrix. The drug (aqueous solubility: 0.17 microg/mL at pH 1-8 and 25 degrees C) was dissolved in a melt of the mixture at 65-70 degrees C and then the hot solution was filled into hard gelatin capsules; the liquid gradually solidified upon cooling below 55 degrees C. The solid system was characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), confocal Raman microscopy (CRM), and the dispersion testing in water. It was confirmed that a solid microemulsion preconcentrate is a two-phase system, where clusters of crystalline PEG 3350 formed the solid structure (m.p. 55-60 degrees C) and the liquid microemulsion preconcentrate dispersed in between PEG 3350 crystals as a separate phase. The drug remained dissolved in the liquid phase. In vitro release testing showed that the preconcentrate dispersed readily in water forming a microemulsion with the drug dissolved in the oil particles (PEG 3350 did not interfere with the process of self-microemulsification.

  20. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    Science.gov (United States)

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane.

  1. tPC-PSAFT modeling of gas solubility in imidazolium-based ionic liquids

    DEFF Research Database (Denmark)

    Karakatsani, Eirini; Economou, Ioannis; Kroon, M. C.

    2007-01-01

    The truncated perturbed chain-polar statistical associating fluid theory (tPC-PSAFT) is re-parametrized for imidazolium-based ionic liquids (ILs) by fitting IL density data over a wide temperature range and restricting the model to predict very low vapor pressure values, in agreement with recent...... experimental evidence. The new set of parameters is used for the correlation of carbon dioxide solubility in various ILs using a binary interaction parameter, k(ij). The correlated k(ij) values are much lower than the values used previously for the same mixtures (Kroon et al., J. Phys. Chem. B 2006, 110, 9262...

  2. Liposomal buccal mucoadhesive film for improved delivery and permeation of water-soluble vitamins.

    Science.gov (United States)

    Abd El Azim, Heba; Nafee, Noha; Ramadan, Alyaa; Khalafallah, Nawal

    2015-07-05

    This study aims at improving the buccal delivery of vitamin B6 (VB6) as a model highly water-soluble, low permeable vitamin. Two main strategies were combined; first VB6 was entrapped in liposomes, which were then formulated as mucoadhesive film. Both plain and VB6-loaded liposomes (LPs) containing Lipoid S100 and propylene glycol (∼ 200 nm) were then incorporated into mucoadhesive film composed of SCMC and HPMC. Results showed prolonged release of VB6 (72.65%, T50% diss 105 min) after 6h from LP-film compared to control film containing free VB6 (96.37%, T50% diss 30 min). Mucoadhesion was assessed both ex vivo on chicken pouch and in vivo in human. Mucoadhesive force of 0.2N and residence time of 4.4h were recorded. Ex vivo permeation of VB6, across chicken pouch mucosa indicated increased permeation from LP-systems compared to corresponding controls. Interestingly, incorporation of the vesicles in mucoadhesive film reduced the flux by 36.89% relative to LP-dispersion. Meanwhile, both films provided faster initial permeation than the liquid forms. Correlating the cumulative percent permeated ex vivo with the cumulative percent released in vitro indicated that LPs retarded VB6 release but improved permeation. These promising results represent a step forward in the field of buccal delivery of water-soluble vitamins. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. HILIC separation and quantitation of water-soluble vitamins using diol column.

    Science.gov (United States)

    Karatapanis, Andreas E; Fiamegos, Yiannis C; Stalikas, Constantine D

    2009-04-01

    Hydrophilic interaction liquid-chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected-water-soluble vitamins using an end-capped HILIC-diol column. Vitamins with significant biological importance, such as thiamine (B(1)), riboflavin (B(2)), nicotinic acid (B(3)), nicotinamide (B(3)), pyridoxine (B(6)), folic acid (B(9)), cyanocobalamin (B(12)) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B(1), B(2), nicotinic acid/nicotinamide, B(6) and C) at ACN-H(2)O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water-soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean-up steps.

  4. Water-Soluble Dried Blood Spot in Protein Analysis: A Proof-of-Concept Study.

    Science.gov (United States)

    Rosting, Cecilie; Gjelstad, Astrid; Halvorsen, Trine Grønhaug

    2015-08-04

    In the present work human chorionic gonadotropin (hCG) was used as a model protein in a proof-of-concept study combining water-soluble dried blood spot (DBS) material in liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based protein analysis. A water-soluble material consisting of commercially available carboxymethyl cellulose (CMC) was evaluated as sampling material for this purpose. The material dissolved readily at physiological pH. Different sample preparation methods were evaluated, and in the final method, 15 μL of whole blood was deposited and dried on CMC before the whole spot was dissolved prior to cleanup by immunoaffinity extraction, tryptic digest, and preconcentration by solid-phase extraction (SPE). The results indicated complete dissolution of hCG from the spots, acceptable limit of detection (LOD) (0.1 IU/mL), linearity (R(2) = 0.959), accuracy (16%), and precision (≤22%). Long-term stability (45 days) of hCG in dried spots at reduced temperatures (≤8 °C) was also demonstrated. The analyte recovery was comparable to the commercially available nonsolvable cellulose material (FTA DMPK-C card).

  5. Solubility isotherms in ternary systems of samarium nitrate, water and nitrates of amidopyrine, benzotriazole

    International Nuclear Information System (INIS)

    Starikova, L.I.

    1991-01-01

    Solubility in the system of samarium nitrate-amidopyrine nitrate-water at 25 and 50 deg C was studied. Solubility isotherms consist of three branches, corresponding to crystallization of samarium nitrate tetrahydrate, amidopyrine nitrate and congruently soluble compounds of Sm(NO 3 ) 3 · 2C 13 H 17 ON 3 ·HNO 3 composition. Its thermal behaviour was studied. The system of samarium nitrate-benzotriazole nitrate-water is referred to eutonic type

  6. 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.

  7. The impact of tritium solubility and diffusivity on inventory and permeation in liquid breeder blankets

    International Nuclear Information System (INIS)

    Caorlin, M.; Gervasini, G.; Reiter, F.

    1988-01-01

    The authors reviewed hydrogen solubility and diffusivity data for liquid lithium-based compounds which are potential breeding blanket materials in NET-type fusion devices. These data have been used to assess tritium permeation and inventory in separately cooled NET blankets and in self cooled blankets with a vanadium first wall. The results for the separately cooled NET-liquid breeder show that tritium permeation is negligible for lithium, a serious problem for Pb-17Li and a critical one for Flibe. The total tritium inventory is lowest in lithium, high in Pb-17Li and very high in Flibe. The high tritium partial pressure for Flibe or Pb-17Li can be reduced in a self cooled blanket with a vanadium first wall. Permeation into the plasma reduces the blanket tritium inventory and permeation. Tritium recovery can be combined with the plasma exhaust

  8. Significance of excipients to enhance the bioavailability of poorly water-soluble drugs in oral solid dosage forms: A Review

    Science.gov (United States)

    Vadlamudi, Manoj Kumar; Dhanaraj, Sangeetha

    2017-11-01

    Nowadays most of the drug substances are coming into the innovation pipeline with poor water solubility. Here, the influence of excipients will play a significant role to improve the dissolution of poorly aqueous soluble compounds. The drug substance needs to be dissolved in gastric fluids to get the better absorption and bioavailability of an orally administered drug. Dissolution is the rate-controlling stage for drugs which controls the rate and degree of absorption. Usually, poorly soluble oral administrated drugs show a slower dissolution rate, inconsistent and incomplete absorption which can lead to lower bioavailability. The low aqueous solubility of BCS class II and IV drugs is a major challenge in the drug development and delivery process. Several technologies have been used in an attempt to progress the bioavailability of poorly water-soluble drug compounds which include solid dispersions, lipid-based formulations, micronization, solvent evaporation, co-precipitation, ordered mixing, liquid-solid compacts, solvent deposition inclusion complexation, and steam aided granulation. In fact, most of the technologies require excipient as a carrier which plays a significant role in improving the bioavailability using Hypromellose acetate succinate, Cyclodextrin, Povidone, Copovidone, Hydroxypropyl cellulose, Hydroxypropyl methylcellulose, Crospovidone, Starch, Dimethylacetamide, Polyethylene glycol, Sodium lauryl sulfate, Polysorbate, Poloxamer. Mesoporous silica and so on. This review deliberates about the excipients significance on bioavailability enhancement of drug products in a single platform along with pragmatically proved applications so that user can able to select the right excipients as per the molecule.

  9. Efficient Enzymatic Synthesis of Phenolic Ester by Increasing Solubility of Phenolic Acids in Ionic Liquids

    DEFF Research Database (Denmark)

    Yang, Zhiyong; Guo, Zheng; Xu, Xuebing

    Compounds from phenolic acid family are well known natural antioxidants, but the application of phenolic acids as antioxidants in industry is limited due to the relatively low solubility in oil-based media. The properties of phenolic acids can be modified through enzymatic lipophilization...... and modified phenolic acids will have amphiphilic property, therefore they can be localized at oil-water or water-oil phase where oxidation is considered to occur frequently. It had been reported that immobilized Candida Antarctica lipase B was the most effective biocatalyst for the various esterification...... reactions, and it had been widely used for esterification of various phenolic acids with fatty alcohol or triglycerides. However, the conversion of phenolic acids is low due to low solubility in hydrophobic solvents and hindrance effect of unsaturated side chain towards the enzyme. Our studies show...

  10. Process for the production of furfural from pentoses and/or water soluble pentosans

    NARCIS (Netherlands)

    De Jong, W.; Marcotullio, G.

    2012-01-01

    The invention is directed to a process for the production of furfural from pentoses and/or water soluble pentosans, said process comprising converting the said pentoses and/or water soluble pentosans in aqueous solution in a first step to furfural and in a second step feeding the aqueous solution

  11. Calorimetric measurements on slightly soluble gases in water

    International Nuclear Information System (INIS)

    Olofsson, G.; Oshodj, A.A.; Qvarnstroem, E.; Wadsoe, I.

    1984-01-01

    Calorimetric measurements have been made of enthalpies of solution Δsub(sol)Hsub(m)sup(infinity) in water of helium, neon, argon, krypton, xenon, methane, ethane, propane, n-butane, and oxygen at 288.15, 298.15, and 308.15 K. Values of the heat-capacity changes Δsub(sol)Csub(p,m)sup(infinity) have been derived. The found values for both the enthalpy and heat-capacity changes for the rare gases and for oxygen fully confirm the values derived by Benson and Krause, Jr. (1976), and Benson, Krause, Jr., and Peterson (1979) from the results of their very careful gas-solubility measurements. The partial molar heat capacities Csub(p,2)sup(infinity) of the hydrocarbons studied were derived. The group-additivity schemes that have been used successfully for the estimation of values for Csub(p,2)sup(infinity) for various non-ionic organic compounds do not correctly predict values of Csub(p,2)sup(infinity) for the hydrocarbons in the present study. (author)

  12. Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes

    Directory of Open Access Journals (Sweden)

    Shixiong Sheng

    2017-12-01

    Full Text Available This study investigated the biodegradation performance and characteristics of Sudan I and Acid Orange 7 (AO7 to improve the biological dye removal efficiency in wastewater and optimize the treatment process. The dyes with different water-solubility and similar molecular structure were biologically treated under aerobic condition in parallel continuous-flow mixed stirred reactors. The biophase analysis using microscopic examination suggested that the removal process of the two azo dyes is different. Removal of Sudan I was through biosorption, since it easily assembled and adsorbed on the surface of zoogloea due to its insolubility, while AO7 was biodegraded incompletely and bioconverted, the AO7 molecule was decomposed to benzene series and inorganic ions, since it could reach the interior area of zoogloea due to the low oxidation-reduction potential conditions and corresponding anaerobic microorganisms. The transformation of NH3-N, SO42− together with the presence of tryptophan-like components confirm that AO7 can be decomposed to non-toxic products in an aerobic bioreactor. This study provides a theoretical basis for the use of biosorption or biodegradation mechanisms for the treatment of different azo dyes in wastewater.

  13. Enhancement of carvedilol solubility by solid dispersion technique using cyclodextrins, water soluble polymers and hydroxyl acid.

    Science.gov (United States)

    Yuvaraja, K; Khanam, Jasmina

    2014-08-05

    Aim of the present work is to enhance aqueous solubility of carvedilol (CV) by solid dispersion technique using wide variety of carriers such as: β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD), tartaric acid (TA), polyvinyl pyrrolidone K-30 (PVP K-30) and poloxamer-407 (PLX-407). Various products of 'CV-solid dispersion' had been studied extensively in various pH conditions to check enhancement of solubility and dissolution characteristics of carvedilol. Any physical change upon interaction between CV and carriers was confirmed by instrumental analysis: XRD, DSC, FTIR and SEM. Negative change of Gibb's free energy and complexation constants (Kc, 75-240M(-1), for cyclodextrins and 1111-20,365M(-1), for PVP K-30 and PLX-407) were the evidence of stable nature of the binding between CV and carriers. 'Solubility enhancement factor' of ionized-CV was found high enough (340 times) with HPβCD in presence of TA. TA increases the binding efficiency of cyclodextrin and changing the pH of microenvironment in dissolution medium. In addition, ionization process was used to increase the apparent intrinsic solubility of drug. In vitro, dissolution time of CV was remarkably reduced in the solid dispersion system compared to that of pure drug. This may be attributed to increased wettability, dispersing ability and transformation of crystalline state of drug to amorphous one. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Overview of milling techniques for improving the solubility of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Zhi Hui Loh

    2015-07-01

    Full Text Available Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a “top–down” approach in the production of fine particles. Fine drug particulates are especially desired in formulations designed for parenteral, respiratory and transdermal use. Most drugs after crystallization may have to be comminuted and this physical transformation is required to various extents, often to enhance processability or solubility especially for drugs with limited aqueous solubility. The mechanisms by which milling enhances drug dissolution and solubility include alterations in the size, specific surface area and shape of the drug particles as well as milling-induced amorphization and/or structural disordering of the drug crystal (mechanochemical activation. Technology advancements in milling now enable the production of drug micro- and nano-particles on a commercial scale with relative ease. This review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of drugs. Salient information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

  15. Study on spraying water soluble resin to reduce pollution for Fukushima daiichi NPP accident

    International Nuclear Information System (INIS)

    Zhang Qiong; Guo Ruiping; Zhang Chunming; Han Fujuan; Hua Jie; Zhang Jiankui

    2012-01-01

    After Fukushima nuclear accident, Tokyo electric power company used the method of spraying water soluble resin synthesis at the scene of the accident, to restrain and control the spread of the radioactive dust, by forming consolidation layer in pollution area surface. This paper briefly introduced the accident, motivation of spraying water soluble resin, spraying range and implementation process. According to the relevant report on Fukushima nuclear accident, the effect of spraying water soluble resin for reducing pollution was analyzed. The mechanism of reducing pollution for water soluble resin and the application prospect were discussed. Spraying water soluble resin for fixing radioactive dust has reasonable reducing pollution effect. It is worth to use as reference and study in China. (authors)

  16. Predicting water solubility of congeners: Chloronaphthalenes-A case study

    Energy Technology Data Exchange (ETDEWEB)

    Puzyn, Tomasz, E-mail: puzi@qsar.eu.org [Faculty of Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Mostrag, Aleksandra; Falandysz, Jerzy [Faculty of Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Kholod, Yana; Leszczynski, Jerzy [NSF CREST Nanotoxicity Center, Department of Chemistry, Jackson State University, 1325 Lynch St, Jackson, MS 39217-0510 (United States)

    2009-10-30

    Since the important physicochemical data for chloronaphtalenes (PCNs) are still scarce, we have predicted water solubility (log S) of all 75 congeners with the Quantitative Structure-Property Relationship (QSPR) scheme. The values of log S, predicted by the most efficient model, varied from 0.01 to 1660 {mu}g dm{sup -3} (2.85 x 10{sup -11}-1.02 x 10{sup -5} mol dm{sup -3}), depending on the number of chlorine atoms present in the molecule and the substitution pattern. We found that the main factor determining relative differences in solubility between the congeners is the solvent accessible volume related to the cavitation process occurring in the solvent. The results are presented as a case study of QSPR modeling for those Persistent Organic Pollutants (POPs) that exist as families of congeners. By investigating the impact of (i) the way of the molecular descriptors' calculation, (ii) the size of applied database and (iii) chemometric method of modeling (Multiple Linear Regression, MLR, and/or Partial Least Squares regression, PLS) on the quality of the models we proposed general recommendations for dealing with congeners. We found that the combination of the B3LYP functional with 6-311++G(d,p) basis set was the most optimal technique of the molecular descriptors' calculation for congeners when comparing with semi-empirical PM3, ab initio Hartee-Fock (HF), and Moller-Pleset 2 (MP2) method carried out with different-size basis sets. Moreover, the model developed with a larger and more general database that includes chloronaphthalenes, polychlorinated dibezno-p-dioxins, furans and biphenyls predicted the values of log S for PCNs noticeable worse than the model calibrated only on PCNs. In the later case it was possible to obtain satisfactory results by employing even the simplest MLR method and only one molecular descriptor. The values of log S were also calculated with the WSKOWIN and COSMO-RS models as the reference techniques and then compared to our

  17. Predicting water solubility of congeners: Chloronaphthalenes-A case study

    International Nuclear Information System (INIS)

    Puzyn, Tomasz; Mostrag, Aleksandra; Falandysz, Jerzy; Kholod, Yana; Leszczynski, Jerzy

    2009-01-01

    Since the important physicochemical data for chloronaphtalenes (PCNs) are still scarce, we have predicted water solubility (log S) of all 75 congeners with the Quantitative Structure-Property Relationship (QSPR) scheme. The values of log S, predicted by the most efficient model, varied from 0.01 to 1660 μg dm -3 (2.85 x 10 -11 -1.02 x 10 -5 mol dm -3 ), depending on the number of chlorine atoms present in the molecule and the substitution pattern. We found that the main factor determining relative differences in solubility between the congeners is the solvent accessible volume related to the cavitation process occurring in the solvent. The results are presented as a case study of QSPR modeling for those Persistent Organic Pollutants (POPs) that exist as families of congeners. By investigating the impact of (i) the way of the molecular descriptors' calculation, (ii) the size of applied database and (iii) chemometric method of modeling (Multiple Linear Regression, MLR, and/or Partial Least Squares regression, PLS) on the quality of the models we proposed general recommendations for dealing with congeners. We found that the combination of the B3LYP functional with 6-311++G(d,p) basis set was the most optimal technique of the molecular descriptors' calculation for congeners when comparing with semi-empirical PM3, ab initio Hartee-Fock (HF), and Moller-Pleset 2 (MP2) method carried out with different-size basis sets. Moreover, the model developed with a larger and more general database that includes chloronaphthalenes, polychlorinated dibezno-p-dioxins, furans and biphenyls predicted the values of log S for PCNs noticeable worse than the model calibrated only on PCNs. In the later case it was possible to obtain satisfactory results by employing even the simplest MLR method and only one molecular descriptor. The values of log S were also calculated with the WSKOWIN and COSMO-RS models as the reference techniques and then compared to our results.

  18. 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.

  19. Liquid chromatographic determination of water

    Science.gov (United States)

    Fortier, N.E.; Fritz, J.S.

    1990-11-13

    A sensitive method for the determination of water in the presence of common interferences is presented. The detection system is based on the effect of water on the equilibrium which results from the reaction aryl aldehydes, such as cinnamaldehyde and methanol in the eluent to form cinnamaldehyde dimethylacetal, plus water. This equilibrium is shifted in a catalytic atmosphere of a hydrogen ion form past column reactor. The extent of the shift and the resulting change in absorbance are proportional to the amount of water present. 1 fig.

  20. Image Charge Effects in the Wetting Behavior of Alkanes on Water with Accounting for Water Solubility

    Directory of Open Access Journals (Sweden)

    Kirill A. Emelyanenko

    2016-03-01

    Full Text Available Different types of surface forces, acting in the films of pentane, hexane, and heptane on water are discussed. It is shown that an important contribution to the surface forces originates from the solubility of water in alkanes. The equations for the distribution of electric potential inside the film are derived within the Debye-Hückel approximation, taking into account the polarization of the film boundaries by discrete charges at water-alkane interface and by the dipoles of water molecules dissolved in the film. On the basis of above equations we estimate the image charge contribution to the surface forces, excess free energy, isotherms of water adsorption in alkane film, and the total isotherms of disjoining pressure in alkane film. The results indicate the essential influence of water/alkane interface charging on the disjoining pressure in alkane films, and the wettability of water surface by different alkanes is discussed.

  1. 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

  2. Determination of insoluble, soluble, and total dietary fiber (CODEX definition) by enzymatic-gravimetric method and liquid chromatography: collaborative study.

    Science.gov (United States)

    McCleary, Barry V; DeVries, Jonathan W; Rader, Jeanne I; Cohen, Gerald; Prosky, Leon; Mugford, David C; Okuma, Kazuhiro

    2012-01-01

    A method for the determination of insoluble (IDF), soluble (SDF), and total dietary fiber (TDF), as defined by the CODEX Alimentarius, was validated in foods. Based upon the principles of AOAC Official Methods 985.29, 991.43, 2001.03, and 2002.02, the method quantitates water-insoluble and water-soluble dietary fiber. This method extends the capabilities of the previously adopted AOAC Official Method 2009.01, Total Dietary Fiber in Foods, Enzymatic-Gravimetric-Liquid Chromatographic Method, applicable to plant material, foods, and food ingredients consistent with CODEX Definition 2009, including naturally occurring, isolated, modified, and synthetic polymers meeting that definition. The method was evaluated through an AOAC/AACC collaborative study. Twenty-two laboratories participated, with 19 laboratories returning valid assay data for 16 test portions (eight blind duplicates) consisting of samples with a range of traditional dietary fiber, resistant starch, and nondigestible oligosaccharides. The dietary fiber content of the eight test pairs ranged from 10.45 to 29.90%. Digestion of samples under the conditions of AOAC 2002.02 followed by the isolation, fractionation, and gravimetric procedures of AOAC 985.29 (and its extensions 991.42 and 993.19) and 991.43 results in quantitation of IDF and soluble dietary fiber that precipitates (SDFP). The filtrate from the quantitation of water-alcohol-insoluble dietary fiber is concentrated, deionized, concentrated again, and analyzed by LC to determine the SDF that remains soluble (SDFS), i.e., all dietary fiber polymers of degree of polymerization = 3 and higher, consisting primarily, but not exclusively, of oligosaccharides. SDF is calculated as the sum of SDFP and SDFS. TDF is calculated as the sum of IDF and SDF. The within-laboratory variability, repeatability SD (Sr), for IDF ranged from 0.13 to 0.71, and the between-laboratory variability, reproducibility SD (SR), for IDF ranged from 0.42 to 2.24. The within

  3. Dual Activity of Hydroxypropyl-β-Cyclodextrin and Water-Soluble Carriers on the Solubility of Carvedilol.

    Science.gov (United States)

    Zoghbi, Abdelmoumin; Geng, Tianjiao; Wang, Bo

    2017-11-01

    Carvedilol (CAR) is a non-selective α and β blocker categorized as class II drug with low water solubility. Several recent studies have investigated ways to overcome this problem. The aim of the present study was to combine two of these methods: the inclusion complex using hydroxypropyl-β-cyclodextrin (HPβCD) with solid dispersion using two carriers: Poloxamer 188 (PLX) and Polyvinylpyrrolidone K-30 (PVP) to enhance the solubility, bioavailability, and the stability of CAR. Kneading method was used to prepare CAR-HPβCD inclusion complex (KD). The action of different carriers separately and in combination on Carvedilol solubility was investigated in three series. CAR-carrier and KD-carrier solid dispersions were prepared by solvent evaporation method. In vitro dissolution test was conducted in three different media: double-distilled water (DDW), simulative gastric fluid (SGF), and PBS pH 6.8 (PBS). The interactions between CAR, HPβCD, and different carriers were explored by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffractometry (XRD), and differential scanning colorimetry (DSC). The results showed higher solubility of CAR in KD-PVP solid dispersions up to 70, 25, and 22 fold compared to pure CAR in DDW, SGF, and PBS, respectively. DSC and XRD analyses indicated an improved degree of transformation of CAR in KD-PVP solid dispersion from crystalline to amorphous state. This study provides a new successful combination of two polymers with the dual action of HPβCD and PLX/PVP on water solubility and bioavailability of CAR.

  4. Sunlight creates oxygenated species in water-soluble fractions of Deepwater horizon oil

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Phoebe Z. [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States); Chen, Huan [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Podgorski, David C. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Future Fuels Institute, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); McKenna, Amy M. [National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005 (United States); Tarr, Matthew A., E-mail: mtarr@uno.edu [Department of Chemistry, University of New Orleans, New Orleans, LA 70148 (United States)

    2014-09-15

    Graphical abstract: Sunlight oxygenates petroleum. - Highlights: • Oxidation seen in water-soluble oil fraction after exposure to simulated sunlight. • Oxygen addition occurred across a wide range of carbon number and DBE. • Oil compounds were susceptible to addition of multiple oxygens to each molecule. • Results provide understanding of fate of oil on water after exposure to sunlight. - Abstract: In order to assess the impact of sunlight on oil fate, Macondo well oil from the Deepwater Horizon (DWH) rig was mixed with pure water and irradiated with simulated sunlight. After irradiation, the water-soluble organics (WSO) from the dark and irradiated samples were extracted and characterized by ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Liquid–liquid extraction yielded two fractions from dark and irradiated water/oil mixtures: acidic WSOs (negative-ion electrospray (ESI)), and base/neutral WSOs (positive-ion ESI) coupled to FT-ICR MS to catalog molecular-level transformations that occur to Macondo-derived WSOs after solar irradiation. Such direct measure of oil phototransformation has not been previously reported. The most abundant heteroatom class detected in the irradiated WSO acid fractions correspond to molecules that contain five oxygens (O{sub 5}), while the most abundant acids in the dark samples contain two oxygen atoms per molecule (O{sub 2}). Higher-order oxygen classes (O{sub 5}–O{sub 9}) were abundant in the irradiated samples, but <1.5% relative abundance in the dark sample. The increased abundance of higher-order oxygen classes in the irradiated samples relative to the dark samples indicates that photooxidized components of the Macondo crude oil become water-soluble after irradiation. The base/neutral fraction showed decreased abundance of pyridinic nitrogen (N{sub 1}) concurrent with an increased abundance of N{sub 1}O{sub x} classes after irradiation. The predominance of higher

  5. Characterization of Polysaccharides from the Fruiting Bodies of Two Species of Genus Ganoderma (Agaricomycetes) and Determination of Water-Soluble β-D-Glucan Using High-Performance Liquid Chromatography.

    Science.gov (United States)

    Liu, Yanfang; Tang, Qingjiu; Yang, Yan; Zhou, Shuai; Wu, Di; Tang, Chuanhong; Zhang, Zhong; Yan, Mengqiu; Feng, Jie; Zhang, Jing-Song

    2017-01-01

    Molecular weight (Mw) distributions of polysaccharides from the fruiting bodies of different Ganoderma lucidum strains and G. sinense were investigated and compared using high-pressure size exclusion chromatography/multiangle laser light scattering/refractive index analysis. Results showed that there were big differences in the Mw distributions and characteristics of polysaccharides from 2 species of Ganoderma. All tested G. lucidum materials exhibited similar polysaccharide distributions and similar characteristics for each fraction. The fraction with highest Mw (peak 1) was identified as β-(1→3)-linked D-glucan with (1→6)-β-D-glucopyranosyl side branches. G. sinense fruiting bodies did not include the β-D-glucan when compared with G. lucidum. A high-pressure size exclusion chromatography method was developed and applied to determine the amount of high-Mw β-D-glucan in G. lucidum fruiting bodies. Results indicated that there was no obvious relationship between β-D-glucan content and the genetic similarity of G. lucidum. The strain labeled "Longzhi no. 2" was determined to possess the largest amount of β-D-glucan: 8.2 mg/mL based on the dry weight of fruiting bodies. The β-D-glucan content in the hot water extract of Longzhi no. 2 reached 17.05%. For the "Hunong no. 1" strain, the β-D-glucan content in log-cultivated fruiting bodies was much higher than that in bag-cultivated ones. This method could be used to improve quality control of polysaccharides in G. lucidum.

  6. Liquid metals replace water steam

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, V

    1976-12-01

    The techniques are described of power generation with regard to their effectiveness which depends on the efficiency of the conversion of thermal energy into electric energy. The magnetohydrodynamic conversion of energy is based on the use of induced electromotive force which results from the movement of the conductor in the magnetic field. The use of liquid metal as the working medium makes it possible to increase the initial temperature of the magnetohydrodynamic cycle to the limit of the highest technically attainable temperatures. The total efficiency of energy conversion in magnetohydrodynamic converters is 2 to 6%.

  7. Liquid metals replace water steam

    International Nuclear Information System (INIS)

    Kozlov, V.

    1976-01-01

    The techniques are described of power generation with regard to their effectiveness which depends on the efficiency of the conversion of thermal energy into electric energy. The magnetohydrodynamic conversion of energy is based on the use of induced electromotive force which results from the movement of the conductor in the magnetic field. The use of liquid metal as the working medium makes it possible to increase the initial temperature of the magnetohydrodynamic cycle to the limit of the highest technically attainable temperatures. The total efficiency of energy conversion in magnetohydrodynamic converters is 2 to 6%. (J.B.)

  8. Reaction rates and electrical resistivities of the hydrogen isotopes with, and their solubilities in, liquid lithium

    International Nuclear Information System (INIS)

    Pulham, R.J.; Adams, P.F.; Hubberstey, P.; Parry, G.; Thunder, A.E.

    1976-01-01

    The rate of reaction, k, of hydrogen and of deuterium with liquid lithium have been determined up to pressures of 20kNm -2 and at temperatures between 230 and 270 0 C. The reaction is first order with an apparent activation energy of 52.8 and 55.2 kJmol -1 for hydrogen and deuterium, respectively. The deuterium isotope effect, k/sub H/k/sub D/, decreases from 2.95 at 230 to 2.83 at 270 0 C. Tritium is predicted to react even more slowly than deuterium. The freezing point of lithium is depressed by 0.082 and 0.075 0 C, respectively, by dissolved hydride and deuteride giving eutectics at 0.016 mol percent H and 0.012 mol percent D in the metal-salt phase diagrams. The depression and eutectic concentration are expected to be less for tritium. The increase in the resistivity of liquid lithium caused by dissolved hydrogen isotopes is linear and relatively large, 5 x 10 -8 Ωm (mol percent H or D) -1 . The solubility of lithium hydride and deuteride was determined from the marked change in resistivity on saturation. The liquidus of the metal-salt phase diagram rises steeply from the eutectic point to meet the two-immiscible liquid region. Tritium is expected to be less soluble than deuterium. The partial molar enthalpies of solution are 44.2 and 55.0 kJmol -1 for hydrogen and deuterium, respectively. These values are used to calculate the solvation enthalpies of the isotope anions in the metal

  9. Solubility of gases in water at high temperature

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, R.J.; Japas, M.L.

    1981-01-01

    In the primary circuits of the PWR, it is usual to find apolar gases such as the noble gases like, nitrogen, hydrogen (deuterium) and oxygen. These gases enter into the circuit partly due to failures in the fuel elements, accidental entries of air into the system and corrosion processes and radiolisis in the coolant media. For the operation of several auxiliary systems in the primary circuit, it is important to know the solubility of these gases in the flux of the circuit and the evaluation of physicochemical processes that take place. A cell has been built that allows to carry out determinations of solubility in the range of 350 deg C and 100 Mega Pascal. Three alternative experimental techniques have been developed to determine the solubility of the gases which are compared to each other. Measures of solubility of argon in H2O and D2O have been made in a wide range of temperatures. (V.B.) [es

  10. Electrochemical detection of dopamine using water-soluble sulfonated graphene

    International Nuclear Information System (INIS)

    Li, Su-Juan; He, Jun-Zhi; Zhang, Meng-Jie; Zhang, Rong-Xia; Lv, Xia-Lei; Li, Shao-Hua; Pang, Huan

    2013-01-01

    Graphical abstract: DPV responses of dopamine (DA) at sulfonated graphene based glassy carbon electrode in the presence of ascorbic acid (AA) and uric acid (UA). The separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 227 mV, 125 mV and 352 mV, which allowed selectively determining DA. -- Abstract: In the present study, a biosensor was prepared using the water-soluble sulfonated graphene with the aim of achieving the selective and sensitive determination of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). The aromatic π–π stacking and electrostatic attraction between positively charged DA and negatively charged sulfonated graphene can accelerate the electron transfer whereas weakening AA and UA oxidation on the sulfonated graphene-modified electrode. Fourier transform infrared spectra (FTIR), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to characterize the successful synthesis of sulfonated graphene sheets. Differential pulse voltammetry was used for electrochemical detection, the separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 227 mV, 125 mV and 352 mV, which allowed selectively determining DA. A broad linear range, low detection limit, along with good ability to suppress the background current from large excess ascorbic acid (AA) and uric acid (UA) were obtained. The as-prepared sulfonated graphene sheets exhibited superior performance over conventional negatively charged Nafion films, such as flexible film thickness, unique nanostructure, excellent anti-interference ability, high sensitivity and selectivity. The proposed method was used to detect DA in real hydrochloride injection sample, human urine and serum samples with satisfactory recovery results

  11. Water soluble vitamin E (TMG) as a radioprotector.

    Science.gov (United States)

    Nair, Cherupally Krishnan K; Devi, Pathirissery Uma; Shimanskaya, R; Kunugita, N; Murase, Hironobu; Gu, Yeun-Hwa; Kagiya, Tsutomu V

    2003-12-01

    Tocopherol monoglucoside (TMG), a water soluble derivative of vitamin E offers protection against deleterious effects of ionizing radiation, both under in vivo and in vitro conditions, to biological systems. TMG was found to be a potent antioxidant and an effective free radical scavenger. It forms a phenoxyl radical similar to trolox upon reaction with various one-electron oxidants. TMG protected DNA from radiation-induced strand breaks. It also protected thymine glycol formation induced by gamma-radiation. Gamma-radiation-induced loss of viability of EL-tumor cells and peroxidation of lipids in microsomal and mitochondrial membranes were prevented by TMG. TMG was nontoxic to mice when administered orally up to 7.0 g/kg body weight. The LD50 dose of TMG for ip administration in mice was 1.15 g/kg body wt. In rats, following oral and ip administration of TMG, the absorption (distribution) half lives were 5.8 and 3.0 min respectively and elimination half lives were 6.7 and 3.1 min respectively. Embryonic mortality resulting from exposure of pregnant mice to ionizing radiation (2 Gy) was reduced by 75% by ip administration of TMG (0.6 g/kg, body wt) prior to irradiation. TMG offered protection to mice against whole body gamma-radiation-induced lethality and weight loss. The LD50(30) of mice increased from 6 to 6.72 Gy upon post irradiation administration of a single dose of TMG (0.6 g/kg, body wt) by ip.

  12. 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.

  13. 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.

  14. Determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of water-soluble tetrazolium salts.

    Science.gov (United States)

    Tsukatani, Tadayuki; Suenaga, Hikaru; Ishiyama, Munetaka; Ezoe, Takatoshi; Matsumoto, Kiyoshi

    2011-07-15

    A method for the determination of water-soluble vitamins using a colorimetric microbial viability assay based on the reduction of the tetrazolium salt {2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8)} via 2-methyl-1,4-napthoquinone (NQ) was developed. Measurement conditions were optimized for the microbiological determination of water-soluble vitamins, such as vitamin B(6), biotin, folic acid, niacin, and pantothenic acid, using microorganisms that have a water-soluble vitamin requirement. A linear relationship between absorbance and water-soluble vitamin concentration was obtained. The proposed method was applied to determine the concentration of vitamin B(6) in various foodstuffs. There was good agreement between vitamin B(6) concentrations determined after 24h using the WST-8 colorimetric method and those obtained after 48h using a conventional method. The results suggest that the WST-8 colorimetric assay is a useful method for the rapid determination of water-soluble vitamins in a 96-well microtiter plate. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Liquid Water Restricts Habitability in Extreme Deserts

    Science.gov (United States)

    Cockell, Charles S.; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water.

  16. Liquid Water Restricts Habitability in Extreme Deserts.

    Science.gov (United States)

    Cockell, Charles S; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water. Key Words: Deserts-Extremophiles-Stress-High temperatures-UV radiation-Desiccation. Astrobiology 17, 309-318.

  17. Enhancement of solubility, antioxidant ability and bioavailability of taxifolin nanoparticles by liquid antisolvent precipitation technique.

    Science.gov (United States)

    Zu, Yuangang; Wu, Weiwei; Zhao, Xiuhua; Li, Yong; Wang, Weiguo; Zhong, Chen; Zhang, Yin; Zhao, Xue

    2014-08-25

    Taxifolin is a kind of flavanonol, whose antioxidant ability is superior to that of ordinary flavonoids compounds owing to its special structure. However, its low bioavailability is a major obstacle for biomedical applications, so the experiment is designed to prepare taxifolin nanoparticles by liquid antisolvent precipitation (LAP) to improve its bioavailability. We selected ethanol as solvent, deionized water as antisolvent, and investigated primarily the type of surfactant and adding amount, drug concentration, volume ratio of antisolvent to solvent, precipitation temperature, dropping speed, stirring speed, stirring time factors affecting drug particles size. Results showed that the poloxamer 188 was selected as the surfactant and the particle size of taxifolin obviously reduced with the increase of the poloxamer 188 concentration, the drug concentration and the dropping speed from 0.08% to 0.45%, from 0.04 g/ml to 0.12 g/ml, from 1 ml/min to 5 ml/min, respectively, when the volume ratio of antisolvent to solvent increased from 2.5 to 20, the particle size of taxifolin first increased and then decreased, the influence of precipitation temperature, stirring speed, stirring time on particle size were not obvious, but along with the increase of mixing time, the drug solution would separate out crystallization. The optimum conditions were: the poloxamer 188 concentration was 0.25%, the drug concentration was 0.08 g/ml, the volume ratio of antisolvent to solvent was 10, the precipitation temperature was 25 °C, the dropping speed was 4 ml/min, the stirring speed was 800 r/min, the stirring time was 5 min. Taxifolin nanosuspension with a MPS of 24.6 nm was obtained under the optimum conditions. For getting taxifolin nanoparticles, the lyophilization method was chosen and correspondingly γ-cyclodextrin was selected as cryoprotectant from γ-cyclodextrin, mannitol, lactose, glucose. Then the properties of raw taxifolin and taxifolin nanoparticles were characterized by

  18. Kinetic measurements of the hydrolytic degradation of cefixime: effect of Captisol complexation and water-soluble polymers.

    Science.gov (United States)

    Mallick, Subrata; Mondal, Arijit; Sannigrahi, Santanu

    2008-07-01

    We have taken kinetic measurements of the hydrolytic degradation of cefixime, and have studied the effect of Captisol complexation and water-soluble polymers on that degradation. The phase solubility of cefixime in Captisol was determined. Kinetic measurements were carried out as a function of pH and temperature. High-performance liquid chromatography (HPLC) was performed to assay all the samples of phase-solubility analysis and kinetic measurements. Chromatographic separation of the degradation products was also performed by HPLC. FT-IR spectroscopy was used to investigate the presence of any interaction between cefixime and Captisol and soluble polymer. The phase-solubility study showed A(L)-type behaviour. The pH-rate profile of cefixime exhibited a U-shaped profile whilst the degradation of cefixime alone was markedly accelerated with elevated temperature. A strong stabilizing influence of the cefixime-Captisol complexation and hypromellose was observed against aqueous mediated degradation, as compared with povidone and macrogol. The unfavourable effect of povidone and macrogol may have been due to the steric hindrance, which prevented the guest molecule from entering the cyclodextrin cavity, whereas hypromellose did not produce any steric hindrance.

  19. Towards improved solubility of poorly water-soluble drugs: cryogenic co-grinding of piroxicam with carrier polymers.

    Science.gov (United States)

    Penkina, Anna; Semjonov, Kristian; Hakola, Maija; Vuorinen, Sirpa; Repo, Timo; Yliruusi, Jouko; Aruväli, Jaan; Kogermann, Karin; Veski, Peep; Heinämäki, Jyrki

    2016-01-01

    Amorphous solid dispersions (SDs) open up exciting opportunities in formulating poorly water-soluble active pharmaceutical ingredients (APIs). In the present study, novel catalytic pretreated softwood cellulose (CPSC) and polyvinylpyrrolidone (PVP) were investigated as carrier polymers for preparing and stabilizing cryogenic co-ground SDs of poorly water-soluble piroxicam (PRX). CPSC was isolated from pine wood (Pinus sylvestris). Raman and Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) were used for characterizing the solid-state changes and drug-polymer interactions. High-resolution scanning electron microscope (SEM) was used to analyze the particle size and surface morphology of starting materials and final cryogenic co-ground SDs. In addition, the molecular aspects of drug-polymer interactions and stabilization mechanisms are presented. The results showed that the carrier polymer influenced both the degree of amorphization of PRX and stabilization against crystallization. The cryogenic co-ground SDs prepared from PVP showed an enhanced dissolution rate of PRX, while the corresponding SDs prepared from CPSC exhibited a clear sustained release behavior. In conclusion, cryogenic co-grinding provides a versatile method for preparing amorphous SDs of poorly water-soluble APIs. The solid-state stability and dissolution behavior of such co-ground SDs are to a great extent dependent on the carrier polymer used.

  20. The water-soluble fraction of potentially toxic elements in contaminated soils: relationships between ecotoxicity, solubility and geochemical reactivity.

    Science.gov (United States)

    Rocha, L; Rodrigues, S M; Lopes, I; Soares, A M V M; Duarte, A C; Pereira, E

    2011-09-01

    To better understand the impacts posed by soil contamination to aquatic ecosystems it is crucial to characterise the links between ecotoxicity, chemical availability and geochemical reactivity of potentially toxic elements (PTE's) in soils. We evaluated the adverse effects of water extracts obtained from soils contaminated by chemical industry and mining, using a test battery including organisms from different trophic levels (bacteria, algae and daphnids). These tests provided a quick assessment of the ecotoxicity of soils with respect to possible adverse effects on aquatic organisms although the ecotoxicological responses could be related to the solubility of PTE's only to a limited extent. The analysis of results of bioassays together with the chemical characterisation of water extracts provided additional relevant insight into the role of conductivity, pH, Al, Fe, and Mn of soil extracts on toxicity to organisms. Furthermore, an important conclusion of this study was that the toxicity of extracts to the aquatic organisms could also be related to the soil properties (pH, Org C and Fe(ox)) and to the reactivity of PTE's in soils which in fact control the soluble fraction of the contaminants. The combined assessment of ecotoxicity in water fractions, solubility and geochemical reactivity of PTE's in soils provided a more comprehensive understanding of the bioavailability of inorganic contaminants than ecotoxicological or chemical studies alone and can therefore be most useful for environmental risks assessment of contaminated soils. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Measurement of hydrogen solubility and desorption rate in V-4Cr-4Ti and liquid lithium-calcium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.H.; Erck, R.; Park, E.T. [Argonne National Lab., IL (United States)] [and others

    1997-04-01

    Hydrogen solubility in V-4Cr-4Ti and liquid lithium-calcium was measured at a hydrogen pressure of 9.09 x 10{sup {minus}4} torr at temperatures between 250 and 700{degrees}C. Hydrogen solubility in V-4Cr-4Ti and liquid lithium decreased with temperature. The measured desorption rate of hydrogen in V-4Cr-4Ti is a thermally activated process; the activation energy is 0.067 eV. Oxygen-charged V-4Cr-4Ti specimens were also investigated to determine the effect of oxygen impurity on hydrogen solubility and desorption in the alloy. Oxygen in V-4Cr-4Ti increases hydrogen solubility and desorption kinetics. To determine the effect of a calcium oxide insulator coating on V-4Cr-4Ti, hydrogen solubility in lithium-calcium alloys that contained 0-8.0 percent calcium was also measured. The distribution ratio R of hydrogen between liquid lithium or lithium-calcium and V-4Cr-4Ti increased as temperature decreased (R {approx} 10 and 100 at 700 and 250{degrees}C, respectively). However at <267{degrees}C, solubility data could not be obtained by this method because of the slow kinetics of hydrogen permeation through the vanadium alloy.

  2. Measurement of hydrogen solubility and desorption rate in V-4Cr-4Ti and liquid lithium-calcium alloys

    International Nuclear Information System (INIS)

    Park, J.H.; Erck, R.; Park, E.T.

    1997-01-01

    Hydrogen solubility in V-4Cr-4Ti and liquid lithium-calcium was measured at a hydrogen pressure of 9.09 x 10 -4 torr at temperatures between 250 and 700 degrees C. Hydrogen solubility in V-4Cr-4Ti and liquid lithium decreased with temperature. The measured desorption rate of hydrogen in V-4Cr-4Ti is a thermally activated process; the activation energy is 0.067 eV. Oxygen-charged V-4Cr-4Ti specimens were also investigated to determine the effect of oxygen impurity on hydrogen solubility and desorption in the alloy. Oxygen in V-4Cr-4Ti increases hydrogen solubility and desorption kinetics. To determine the effect of a calcium oxide insulator coating on V-4Cr-4Ti, hydrogen solubility in lithium-calcium alloys that contained 0-8.0 percent calcium was also measured. The distribution ratio R of hydrogen between liquid lithium or lithium-calcium and V-4Cr-4Ti increased as temperature decreased (R ∼ 10 and 100 at 700 and 250 degrees C, respectively). However at <267 degrees C, solubility data could not be obtained by this method because of the slow kinetics of hydrogen permeation through the vanadium alloy

  3. Comparison of Aqueous and 1-Octanol Solubility as well as Liquid?Liquid Distribution of Acyclovir Derivatives and Their Complexes with Hydroxypropyl-?-Cyclodextrin

    OpenAIRE

    Ko?bia?, Ma?gorzata; Gierycz, Pawe?

    2013-01-01

    The aim of the presented work is the comparison of aqueous and 1-octanol solubilities of different acyclovir derivatives and their hydroxypropyl-?-cyclodextrin inclusion complexes. The solubility measurements were carried out at different temperatures over the range 25?45??C using water, 1-octanol, water saturated with 1-octanol, 1-octanol saturated with water, buffered aqueous solutions (pH?=?5.5 and 7.0) and buffered aqueous solutions containing cyclodextrin as solvents. The aqueous solubil...

  4. Bioassay using the water soluble fraction of a Nigerian Light Crude ...

    African Journals Online (AJOL)

    Summary: A 96-hour bioassay was conducted using the water soluble fraction of a Nigerian light crude oil sample on Clarias gariepinus fingerlings. 0, 2.5, 5.0, 7.5 and 10 mls of water soluble fractions (WSF) of the oil were added to 1000 litres of de-chlorinated tap water to form 0, 25, 50 , 75 and 100 parts per million ...

  5. Polymer-assisted synthesis of water-soluble PbSe quantum dots

    International Nuclear Information System (INIS)

    Melnig, V.; Apostu, M.-O.; Foca, N.

    2008-01-01

    Stable PbSe quantum dots were synthesised in water-based media using poly(amidehydroxyurethane) water-soluble polymer. The polymer acts like a precursor carrier, blocks the particles aggregation and assures their solubility. Atomic force microscopy data show that the particle radius is smaller than the Bohr radius of PbSe. Interactions studies, performed by Fourier transform IR spectroscopy, show that the quantum dots are capped with poly(amidehydroxyurethane). The proposed synthesis was realised in the absence of any organic solvent. As a result, the produced particles have good water solubility, stability and good arguments to be biologically compatible.

  6. The synthesis of a water-soluble derivative of rutin as an antiradical agent

    Energy Technology Data Exchange (ETDEWEB)

    Pedriali, Carla Aparecida; Fernandes, Adjaci Uchoa [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Dept. de Bioquimica]. E-mail: capedriali@hotmail.com; Bernusso, Leandra de Cassia; Polakiewicz, Bronislaw [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Tecnologia Bioquimico-Farmaceutica

    2008-07-01

    The purpose of this study was to synthesize a water-soluble derivative of rutin (compound 2) by introducing carboxylate groups on rutin's sugar moiety. The rutin derivative showed an almost 100-fold solubility increase in water. The antiradical capacity of compound 2 was evaluated using the luminol/AAPH system, and the derivative's activity was 1.5 times greater than that of Trolox. Despite the derivative's high solubility in water (log P = -1.13), lipid peroxidation of brain homogenate membranes was very efficiently inhibited (inhibition values were only 19% lower than the inhibition values of rutin). (author)

  7. The synthesis of a water-soluble derivative of rutin as an antiradical agent

    International Nuclear Information System (INIS)

    Pedriali, Carla Aparecida; Fernandes, Adjaci Uchoa; Bernusso, Leandra de Cassia; Polakiewicz, Bronislaw

    2008-01-01

    The purpose of this study was to synthesize a water-soluble derivative of rutin (compound 2) by introducing carboxylate groups on rutin's sugar moiety. The rutin derivative showed an almost 100-fold solubility increase in water. The antiradical capacity of compound 2 was evaluated using the luminol/AAPH system, and the derivative's activity was 1.5 times greater than that of Trolox. Despite the derivative's high solubility in water (log P = -1.13), lipid peroxidation of brain homogenate membranes was very efficiently inhibited (inhibition values were only 19% lower than the inhibition values of rutin). (author)

  8. Cross-linking of wheat gluten using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Tropini, V.; Lens, J.P.; Mulder, W.J.; Silvestre, F.

    2000-01-01

    Wheat gluten was cross-linked using water-soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide HCl (EDC). To enhance cross-linking, N-hydroxysuccinimide (NHS) was added to the reaction mixture. The cross-linking efficiency was evaluated by the decrease in the amount of amino groups, the solubility

  9. Solubility of corrosion products of plain steel in oxygen-containing water solutions at high parameters

    International Nuclear Information System (INIS)

    Martynova, O.I.; Samojlov, Yu.F.; Petrova, T.I.; Kharitonova, N.L.

    1983-01-01

    Technique for calculation of solubility of iron corrosion products in oxygen-containing aqueous solutions in the 298-573 K temperature range is presented. Solubility of corrosion products of plain steel in deeply-desalinizated water in the presence of oxygen for the such range of the temperatures is experimentally determined. Rather good convergence between calculated and experimental data is noted

  10. Formulation of a poorly water-soluble drug in sustained-release hollow granules with a high viscosity water-soluble polymer using a fluidized bed rotor granulator.

    Science.gov (United States)

    Asada, Takumi; Yoshihara, Naoki; Ochiai, Yasushi; Kimura, Shin-Ichiro; Iwao, Yasunori; Itai, Shigeru

    2018-04-25

    Water-soluble polymers with high viscosity are frequently used in the design of sustained-release formulations of poorly water-soluble drugs to enable complete release of the drug in the gastrointestinal tract. Tablets containing matrix granules with a water-soluble polymer are preferred because tablets are easier to handle and the multiple drug-release units of the matrix granules decreases the influences of the physiological environment on the drug. However, matrix granules with a particle size of over 800 μm sometimes cause a content uniformity problem in the tableting process because of the large particle size. An effective method of manufacturing controlled-release matrix granules with a smaller particle size is desired. The aim of this study was to develop tablets containing matrix granules with a smaller size and good controlled-release properties, using phenytoin as a model poorly water-soluble drug. We adapted the recently developed hollow spherical granule granulation technology, using water-soluble polymers with different viscosities. The prepared granules had an average particle size of 300 μm and sharp particle size distribution (relative width: 0.52-0.64). The values for the particle strength of the granules were 1.86-1.97 N/mm 2 , and the dissolution profiles of the granules were not affected by the tableting process. The dissolution profiles and the blood concentration levels of drug released from the granules depended on the viscosity of the polymer contained in the granules. We succeeded in developing the desired controlled-release granules, and this study should be valuable in the development of sustained-release formulations of poorly water-soluble drugs. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Printable polymer actuators from ionic liquid, soluble polyimide, and ubiquitous carbon materials.

    Science.gov (United States)

    Imaizumi, Satoru; Ohtsuki, Yuto; Yasuda, Tomohiro; Kokubo, Hisashi; Watanabe, Masayoshi

    2013-07-10

    We present here printable high-performance polymer actuators comprising ionic liquid (IL), soluble polyimide, and ubiquitous carbon materials. Polymer electrolytes with high ionic conductivity and reliable mechanical strength are required for high-performance polymer actuators. The developed polymer electrolytes comprised a soluble sulfonated polyimide (SPI) and IL, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide ([C2mim][NTf2]), and they exhibited acceptable ionic conductivity up to 1 × 10(-3) S cm(-1) and favorable mechanical properties (elastic modulus >1 × 10(7) Pa). Polymer actuators based on SPI/[C2mim][NTf2] electrolytes were prepared using inexpensive activated carbon (AC) together with highly electron-conducting carbon such as acetylene black (AB), vapor grown carbon fiber (VGCF), and Ketjen black (KB). The resulting polymer actuators have a trilaminar electric double-layer capacitor structure, consisting of a polymer electrolyte layer sandwiched between carbon electrode layers. Displacement, response speed, and durability of the actuators depended on the combination of carbons. Especially the actuators with mixed AC/KB carbon electrodes exhibited relatively large displacement and high-speed response, and they kept 80% of the initial displacement even after more than 5000 cycles. The generated force of the actuators correlated with the elastic modulus of SPI/[C2mim][NTf2] electrolytes. The displacement of the actuators was proportional to the accumulated electric charge in the electrodes, regardless of carbon materials, and agreed well with the previously proposed displacement model.

  12. Formulation of a Novel Nano emulsion System for Enhanced Solubility of a Sparingly Water Soluble Antibiotic, Clarithromycin

    International Nuclear Information System (INIS)

    Vatsraj, S.; Pathak, H.; Chauhan, K.

    2014-01-01

    The sparingly water soluble property of majority of medicinally significant drugs acts as a potential barrier towards its utilization for therapeutic purpose. The present study was thus aimed at development of a novel oil-in-water (o/w) nano emulsion (NE) system having ability to function as carrier for poorly soluble drugs with clarithromycin as a model antibiotic. The therapeutically effective concentration of clarithromycin, 5 mg/mL, was achieved using polysorbate 80 combined with olive oil as lipophilic counterion. A three-level three-factorial central composite experimental design was utilized to conduct the experiments. The effects of selected variables, polysorbate 80 and olive oil content and concentration of polyvinyl alcohol, were investigated. The particle size of clarithromycin for the optimized formulation was observed to be 30 nm. The morphology of the nano emulsion was explored using transmission electron microscopy (TEM). The emulsions prepared with the optimized formula demonstrated good physical stability during storage at room temperature. Antibacterial activity was conducted with the optimized nano emulsion NESH 01 and compared with free clarithromycin. Zone of inhibition was larger for NESH 01 as compared to that with free clarithromycin. This implies that the solubility and hence the bioavailability of clarithromycin has increased in the formulated nano emulsion system.

  13. N-succinyl-chitosan as a drug carrier: water-insoluble and water-soluble conjugates.

    Science.gov (United States)

    Kato, Yoshinori; Onishi, Hiraku; Machida, Yoshiharu

    2004-02-01

    N-succinyl-chitosan (Suc-Chi) has favourable properties as a drug carrier such as biocompatibility, low toxicity and long-term retention in the body. It was long retained in the systemic circulation after intravenous administration, and the plasma half-lives of Suc-Chi (MW: 3.4 x 10(5); succinylation degree: 0.81 mol/sugar unit; deacetylation degree: 1.0 mol/sugar unit) were ca. 100.3h in normal mice and 43 h in Sarcoma 180-bearing mice. The biodistribution of Suc-Chi into other tissues was trace apart from the prostate and lymph nodes. The maximum tolerable dose for the intraperitoneal injection of Suc-Chi to mice was greater than 2 g/kg. The water-insoluble and water-soluble conjugates could be prepared using a water-soluble carbodiimide and mitomycin C (MMC) or using an activated ester of glutaric MMC. In vitro release characteristics of these conjugates showed similar patterns, i.e. a pH-dependent manner, except that water-insoluble conjugates showed a slightly slower release of MMC than water-soluble ones. The conjugates of MMC with Suc-Chi showed good antitumour activities against various tumours such as murine leukaemias (L1210 and P388), B16 melanoma, Sarcoma 180 solid tumour, a murine liver metastatic tumour (M5076) and a murine hepatic cell carcinoma (MH134). This review summarizes the utilization of Suc-Chi as a drug carrier for macromolecular conjugates of MMC and the therapeutic efficacy of the conjugates against various tumours.

  14. Perspective on the structure of liquid water

    International Nuclear Information System (INIS)

    Nilsson, A.; Pettersson, L.G.M.

    2011-01-01

    Graphical abstract: Liquid water can be described in a fluctuating inhomogeneous picture with two local structural motifs that are spatially separated. At ambient temperatures most molecules favor a closer packing than tetrahedral, with strongly distorted hydrogen bonds giving higher density (yellow), which allows the quantized librational modes to be excited and contribute to the entropy, but with enthalpically favored tetrahedrally bonded water patches appearing as fluctuations (blue), i.e. a competition between entropy and enthalpy. Upon cooling water the amount of molecules participating in tetrahedral structures and the size of the tetrahedral patches increase. Highlights: ► Two components maximizing either enthalpy (tetrahedral, low-density) or entropy (non-specific H-bonding, higher density). ► Interconvert discontinuously and ratio depends on temperature. ► Density fluctuations on 1 nm length scale. ► Increasing size in supercooled region. ► Connection to Widom line and 2nd critical point. - Abstract: We present a picture that combines discussions regarding the thermodynamic anomalies in ambient and supercooled water with recent interpretations of X-ray spectroscopy and scattering data of water in the ambient regime. At ambient temperatures most molecules favor a closer packing than tetrahedral, with strongly distorted hydrogen bonds, which allows the quantized librational modes to be excited and contribute to the entropy, but with enthalpically favored tetrahedrally bonded water patches appearing as fluctuations, i.e. a competition between entropy and enthalpy. Upon cooling water the amount of molecules participating in tetrahedral structures and the size of the tetrahedral patches increase. The two local structures are connected to the liquid–liquid critical point hypothesis in supercooled water corresponding to high density liquid and low density liquid. We will discuss the interpretation of X-ray absorption spectroscopy, X-ray emission

  15. 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

  16. Review: kinetics of water-soluble contrast media in the central nervous system

    International Nuclear Information System (INIS)

    Sage, M.R.

    1983-01-01

    In neuroradiology, intraarterial, intravenous, and intrathecal injections of water-soluble contrast media are made. With the growing importance of water-soluble myelography, interventional angiography, and enhanced computed tomography (CT), it is essential to have a clear understanding of the response of the nervous system to such procedures. The blood, cerebrospinal fluid (CSF), and extracellular fluid of the parenchyma form the fluid compartments of the brain with three interfaces between, namely, the blood-brain interface, the CSF-brain interface, and the blood-CSF interface. One of more of these interfaces are exposed to water-soluble contrast media after intraarterial, intravenous, or intrathecal administration. The behavior of water-soluble contrast media at these interfaces is discussed on the basis of local experience and a review of the literature

  17. Comparative toxicity of water soluble fractions of four oils on the growth of a Microalga

    Digital Repository Service at National Institute of Oceanography (India)

    Phatarpekar, P.V.; Ansari, Z.A.

    Toxic effects of water soluble fractions (WSF) of four different fuel oils on a microalga. Tetraselmis gracilis, were examined and compared. On applying different concentrations of WSF, a decrease in cell population was observed. Depending...

  18. Application of spray-drying and electrospraying/electospinning for poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Bohr, Adam; Boetker, Johan P; Rades, Thomas

    2014-01-01

    Solid dispersions have been widely studied as an attractive formulation strategy for the increasingly prevalent poorly water-soluble drug compounds, including herbal medicines, often leading to improvements in drug dissolution rate and bioavailability. However, several challenges are encountered...

  19. Calculated solubility isotherm of a system of alkaline earth sulfates and hydroxides in water

    International Nuclear Information System (INIS)

    MOshinskii, A.S.; TIkomirova, K.A.

    1986-01-01

    Tis paper examines the calculation of the isothermal solubility diagram of a system of alkaline earth sulfates and hydroxides in water which makes it possible to substantiate, to a considerable extent, the natural physicochemical mineralization of natural waters, in particular water from geochemical sources. The present paper investigates the solubility of the equilibrium solid phases of a system of alkaline earth sulfates and hydroxides in water. A projection is shown of the composition prism of the quinary reciprocal system with demarcation of the crystallization areas of each sulfate and hydroxide of the component subsystems. The computational formulas for calculating solubility were derived from the solubility product principle, with allowance for ion activity coefficients in saturated hydroxide solutions

  20. Structural Characterization of Febuxostat/l-Pyroglutamic Acid Cocrystal Using Solid-State 13C-NMR and Investigational Study of Its Water Solubility

    OpenAIRE

    Ji-Hun An; Changjin Lim; Hyung Chul Ryu; Jae Sun Kim; Hyuk Min Kim; Alice Nguvoko Kiyonga; Minho Park; Young-Ger Suh; Gyu Hwan Park; Kiwon Jung

    2017-01-01

    Febuxostat (FB) is a poorly water-soluble drug that belongs to BCS class II. The drug is employed for the treatment of inflammatory disease arthritis urica (gout), and the free base, FB form-A, is most preferred for drug formulation. In order to achieve a goal of improving the water solubility of FB form-A, this study was carried out using the cocrystallization technique called the liquid-assisted grinding method to produce FB cocrystals. Here, five amino acids containing amine (NH), oxygen (...

  1. Intestinal absorption of water-soluble vitamins in health and disease

    OpenAIRE

    Said, Hamid M.

    2011-01-01

    Our knowledge of the mechanisms and regulation of intestinal absorption of water-soluble vitamins under normal physiological conditions, and of the factors/conditions that affect and interfere with theses processes has been significantly expanded in recent years as a result of the availability of a host of valuable molecular/cellular tools. Although structurally and functionally unrelated, the water-soluble vitamins share the feature of being essential for normal cellular functions, growth an...

  2. The role of vitamins in the diet of the elderly II. Water-soluble vitamins

    OpenAIRE

    Csapó J.; Albert Cs.; Prokisch J.

    2017-01-01

    Following a presentation of humans’ water-soluble vitamin requirements, the authors will discuss in detail the role these vitamins play in human organism and outline those major biochemical processes that are negatively affected in the body in case of vitamin deficiency. They point out that in the elderly population of developed countries cases of water-soluble vitamin deficiency are extremely rare and they are due to the lack of dietary vitamin, but mostly to the vitamin being released from ...

  3. Effect of fasting on the urinary excretion of water-soluble vitamins in humans and rats.

    Science.gov (United States)

    Fukuwatari, Tsutomu; Yoshida, Erina; Takahashi, Kei; Shibata, Katsumi

    2010-01-01

    Recent studies showed that the urinary excretion of the water-soluble vitamins can be useful as a nutritional index. To determine how fasting affects urinary excretion of water-soluble vitamins, a human study and an animal experiment were conducted. In the human study, the 24-h urinary excretion of water-soluble vitamins in 12 healthy Japanese adults fasting for a day was measured. One-day fasting drastically decreased urinary thiamin content to 30%, and increased urinary riboflavin content by 3-fold. Other water-soluble vitamin contents did not show significant change by fasting. To further investigate the alterations of water-soluble vitamin status by starvation, rats were starved for 3 d, and water-soluble vitamin contents in the liver, blood and urine were measured during starvation. Urinary excretion of thiamin, riboflavin, vitamin B(6) metabolite 4-pyridoxic acid, nicotinamide metabolites and folate decreased during starvation, but that of vitamin B(12), pantothenic acid and biotin did not. As for blood vitamin levels, only blood vitamin B(1), plasma PLP and plasma folate levels decreased with starvation. All water-soluble vitamin contents in the liver decreased during starvation, whereas vitamin concentrations in the liver did not decrease. Starvation decreased only concentrations of vitamin B(12) and folate in the skeletal muscle. These results suggest that water-soluble vitamins were released from the liver, and supplied to the peripheral tissues to maintain vitamin nutrition. Our human study also suggested that the effect of fasting should be taken into consideration for subjects showing low urinary thiamin and high urinary riboflavin.

  4. Evaluation of ammonium nitrate phosphate (Suphala) having different water soluble phosphorus levels on black soils

    International Nuclear Information System (INIS)

    Deo Dutt; Mutatkar, V.K.; Chapke, V.G.

    1974-01-01

    Efficiency of the laboratory prepared 32 P tagged ammonium nitrate phosphate (Suphala) varying in water soluble P was studied both on calcareous and non-calcareous soils of Maharashtra for bajra and wheat crops under greenhouse conditions. The results revealed a significant increase in dry matter production and uptake of total and fertilizer P with Suphala containing 30-32% water-soluble phosphorus. (author)

  5. Abalone water-soluble matrix for self-healing biomineralization of tooth defects

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Zhenliang [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Chen, Jingdi, E-mail: ibptcjd@fzu.edu.cn [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Wang, Hailiang [The Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou 350002 (China); Zhong, Shengnan; Hu, Yimin; Wang, Zhili [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Zhang, Qiqing, E-mail: zhangqiq@126.com [Institute of Biomedical and Pharmaceutical Technology, Fuzhou University, Fuzhou 350002 (China); Institute of Biomedical Engineering, Chinese Academy of Medical Science & Peking Union Medical College, Tianjin 300192 (China)

    2016-10-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% the abalone water-soluble protein (AWSPro) and 2.04 wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. - Graphical abstract: In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% abalone water-soluble protein (AWSPro) and 2.04 wt% abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro by self-organized. Display Omitted - Highlights: • Provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell. • The abalone shell water-soluble matrix contains protein and polysaccharide. • The abalone water-soluble matrix can efficiently induce remineralization of HAP by self-organized. • Achieved self-healing biomineralization of tooth defects in

  6. 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...

  7. Abalone water-soluble matrix for self-healing biomineralization of tooth defects

    International Nuclear Information System (INIS)

    Wen, Zhenliang; Chen, Jingdi; Wang, Hailiang; Zhong, Shengnan; Hu, Yimin; Wang, Zhili; Zhang, Qiqing

    2016-01-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% the abalone water-soluble protein (AWSPro) and 2.04 wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. - Graphical abstract: In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53 wt% abalone water-soluble protein (AWSPro) and 2.04 wt% abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro by self-organized. Display Omitted - Highlights: • Provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell. • The abalone shell water-soluble matrix contains protein and polysaccharide. • The abalone water-soluble matrix can efficiently induce remineralization of HAP by self-organized. • Achieved self-healing biomineralization of tooth defects in vitro.

  8. Impact of bleaching agents on water sorption and solubility of resin luting cements.

    Science.gov (United States)

    Torabi Ardakani, Mahshid; Atashkar, Berivan; Bagheri, Rafat; Burrow, Michael F

    2017-08-01

    The aim of the present study was to evaluate the effect of distilled water and home and office bleaching agents on the sorption and solubility of resin luting cements. A total of 18 disc-shaped specimens were prepared from each of four resin cements: G-CEM LinkAce, Panavia F, Rely X Unicem, and seT. Specimens were cured according to the manufacturers' instructions and randomly divided into three groups of six, where they were treated with either an office or home bleaching agent or immersed in distilled water (control). Water sorption and solubility were measured by weighing the specimens before and after immersion and desiccation. Data were analyzed using Pearson correlation coefficient, two-way analysis of variance (ANOVA) and Tukey's test. There was a significant, positive correlation between sorption and solubility. Two-way anova showed significant differences among all resin cements tested for either sorption or solubility. Water sorption and solubility of all cements were affected significantly by office bleaching, and even more by home bleaching agents. Sorption and solubility behavior of the studied cements were highly correlated and significantly affected by applying either office or home bleaching agents; seT showed the highest sorption and solubility, whereas Rely X Unicem revealed the lowest. © 2016 John Wiley & Sons Australia, Ltd.

  9. Solubility of Stevioside and Rebaudioside A in water, ethanol and their binary mixtures

    Directory of Open Access Journals (Sweden)

    Liliana S. Celaya

    2016-10-01

    Full Text Available In order to investigate the solubility of Stevioside and Rebaudioside A in different solvents (ethanol, water, ethanol:water 30:70 and ethanol:water 70:30, supersaturated solutions of pre-crystalized steviol glycosides were maintained at different temperatures (from 5 °C to 50 °C to reach equilibrium. Under these conditions significant differences were found in the extent of solubility. Rebaudioside A was poorly soluble in ethanol and water, and Stevioside was poorly soluble in water. Solvent mixtures more effectively promoted solubilisation, and a significant effect of temperature on solubility was observed. The two steviol glycosides showed higher solubilities and this behavior was promoted by the presence of the other sweetener. The polarity indices of the solvents were determined, and helped to explain the observed behavior. Several solute-solvent and solute-solute interactions can occur, along with the incidence of a strong affinity between solvents. The obtained results are in accordance with technological applications of ethanol, water and their binary mixtures for Stevioside and Rebaudioside A separations.

  10. Buckminsterfullerene's (C60) octanol-water partition coefficient (Kow) and aqueous solubility.

    Science.gov (United States)

    Jafvert, Chad T; Kulkarni, Pradnya P

    2008-08-15

    To assess the risk and fate of fullerene C60 in the environment, its water solubility and partition coefficients in various systems are useful. In this study, the log Kow of C60 was measured to be 6.67, and the toluene-water partition coefficient was measured at log Ktw = 8.44. From these values and the respective solubilities of C60 in water-saturated octanol and water-saturated toluene, C60's aqueous solubility was calculated at 7.96 ng/L(1.11 x 10(-11) M) for the organic solvent-saturated aqueous phase. Additionally, the solubility of C60 was measured in mixtures of ethanol-water and tetrahydrofuran-water and modeled with Wohl's equation to confirm the accuracy of the calculated solubility value. Results of a generator column experiment strongly support the hypothesis that clusters form at aqueous concentrations below or near this calculated solubility. The Kow value is compared to those of other hydrophobic organic compounds, and bioconcentration factors for C60 were estimated on the basis of Kow.

  11. Encapsulation of β-carotene within ferritin nanocages greatly increases its water-solubility and thermal stability.

    Science.gov (United States)

    Chen, Lingli; Bai, Guangling; Yang, Rui; Zang, Jiachen; Zhou, Ting; Zhao, Guanghua

    2014-04-15

    Carotenoids may play a number of potential health benefits for human. However, their use in food industry is limited mostly because of their poor water-solubility and low thermal stability. Ferritins are widely distributed in nature with a shell-like structure which offers a great opportunity to improve the water-solubility and thermal stability of the carotenoids by encapsulation. In this work, recombinant human H-chain ferritin (rHuHF) was prepared and used to encapsulate β-carotene, a typical compound among carotenoids, by taking advantage of the reversible dissociation and reassembly characteristic of apoferritin in different pH environments. Results from high-performance liquid chromatography (HPLC), UV/Vis spectroscopy and transmission electron microscope (TEM) indicated that β-carotene molecules were successfully encapsulated within protein cages with a β-carotene/protein molar ratio of 12.4-1. Upon such encapsulation, these β-carotene-containing apoferritin nanocomposites were water-soluble. Interestingly, the thermal stability of the β-carotene encapsulated within apoferritin nanocages was markedly improved as compared to free β-carotene. These new properties might be favourable to the utilisation of β-carotene in food industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Oral water soluble contrast for malignant bowel obstruction.

    Science.gov (United States)

    Syrmis, William; Richard, Russell; Jenkins-Marsh, Sue; Chia, Siew C; Good, Phillip

    2018-03-07

    Malignant bowel obstruction (MBO) is a common problem in patients with intra-abdominal cancer. Oral water soluble contrast (OWSC) has been shown to be useful in the management of adhesive small bowel obstruction in identifying patients who will recover with conservative management alone and also in reducing the length of hospital stay. It is not clear whether the benefits of OWSC in adhesive small bowel obstruction are also seen in patients with MBO. To determine the reliability of OWSC media and follow-up abdominal radiographs in predicting the success of conservative treatment in resolving inoperable MBO with conservative management.To determine the efficacy and safety of OWSC media in reducing the duration of obstruction and reducing hospital stay in people with MBO. We identified studies from searching Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and MEDLINE in Process, Embase, CINAHL, Science Citation Index (Web of Science) and Conference Proceedings Citation Index - Science (Web of Science). We also searched registries of clinical trials and the CareSearch Grey Literature database. The date of the search was the 6 June 2017. Randomised controlled trials (RCTs), or prospective controlled studies, that evaluated the diagnostic potential of OWSC in predicting which malignant bowel obstructions will resolve with conservative treatment.RCTs, or prospective controlled studies, that assessed the therapeutic potential of OWSC in managing MBO at any level compared with placebo, no intervention or usual treatment or supportive care. We used standard methodological procedures expected by Cochrane. We assessed risk of bias and assessed the evidence using GRADE and created a 'Summary of findings' table. We found only one RCT meeting the selection criteria for the second objective (therapeutic potential) of this review. This study recruited nine participants. It compared the use of gastrografin versus placebo in adult patients with MBO with no

  13. Predictions of flavonoid solubility in ionic liquids by COSMO-RS: experimental verification, structural elucidation, and solvation characterization

    DEFF Research Database (Denmark)

    Guo, Zheng; Lue, Bena-Marie; Thomsen, Kaj

    2007-01-01

    Predictions of the solubility of flavonoids in a large variety of ionic liquids (ILs) with over 1800 available structures were examined based on COSMO-RS computation. The results show that the solubilities of flavonoids are strongly anion-dependent. Experimental measurement of the solubilities...... of esculin and rutin in 12 ILs with varying anions and cations show that predicted and experimental results generally have a good agreement. Based on the sound physical basis of COSMO-RS, the solubility changes of flavonoids were quantitatively associated with solvation interactions and structural...... characteristics of ILs. COSMO-RS derived parameters, i.e. misfit, H-bonding and van der Waals interaction energy, are shown to be capable of characterizing the complicated multiple interactions in the IL system effectively. H-bonding interaction is the most dominant interaction for ILs (followed by misfit and van...

  14. Nootkatone encapsulation by cyclodextrins: Effect on water solubility and photostability.

    Science.gov (United States)

    Kfoury, Miriana; Landy, David; Ruellan, Steven; Auezova, Lizette; Greige-Gerges, Hélène; Fourmentin, Sophie

    2017-12-01

    Nootkatone (NO) is a sesquiterpenoid volatile flavor, used in foods, cosmetics and pharmaceuticals, possessing also insect repellent activity. Its application is limited because of its low aqueous solubility and stability; this could be resolved by encapsulation in cyclodextrins (CDs). This study evaluated the encapsulation of NO by CDs using phase solubility studies, Isothermal Titration Calorimetry, Nuclear Magnetic Resonance spectroscopy and molecular modeling. Solid CD/NO inclusion complex was prepared and characterized for encapsulation efficiency and loading capacity using UV-Visible. Thermal properties were investigated by thermogravimetric-differential thermal analysis and release studies were performed using multiple headspace extraction. Formation constants (K f ) proved the formation of stable inclusion complexes. NO aqueous solubility, photo- and thermal stability were enhanced and the release could be insured from solid complex in aqueous solution. This suggests that CDs are promising carrier to improve NO properties and, consequently, to enlarge its use in foods, cosmetics, pharmaceuticals and agrochemicals preparations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. WATER ACTIVITY DATA ASSESSMENT TO BE USED IN HANFORD WASTE SOLUBILITY CALCULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    DISSELKAMP RS

    2011-01-06

    The purpose of this report is to present and assess water activity versus ionic strength for six solutes:sodium nitrate, sodium nitrite, sodium chloride, sodium carbonate, sodium sulfate, and potassium nitrate. Water activity is given versus molality (e.g., ionic strength) and temperature. Water activity is used to estimate Hanford crystal hydrate solubility present in the waste.

  16. WATER ACTIVITY DATA ASSESSMENT TO BE USED IN HANFORD WASTE SOLUBILITY CALCULATIONS

    International Nuclear Information System (INIS)

    Disselkamp, R.S.

    2011-01-01

    The purpose of this report is to present and assess water activity versus ionic strength for six solutes:sodium nitrate, sodium nitrite, sodium chloride, sodium carbonate, sodium sulfate, and potassium nitrate. Water activity is given versus molality (e.g., ionic strength) and temperature. Water activity is used to estimate Hanford crystal hydrate solubility present in the waste.

  17. Prediction of solubilities for ginger bioactive compounds in hot water by the COSMO-RS method

    Science.gov (United States)

    Zaimah Syed Jaapar, Syaripah; Azian Morad, Noor; Iwai, Yoshio

    2013-04-01

    The solubilities in water of four main ginger bioactives, 6-gingerol, 6-shogaol, 8-gingerol and 10-gingerol, were predicted using a conductor-like screening model for real solvent (COSMO-RS) calculations. This study was conducted since no experimental data are available for ginger bioactive solubilities in hot water. The σ-profiles of these selected molecules were calculated using Gaussian software and the solubilities were calculated using the COSMO-RS method. The solubilities of these ginger bioactives were calculated at 50 to 200 °C. In order to validate the accuracy of the COSMO-RS method, the solubilities of five hydrocarbon molecules were calculated using the COSMO-RS method and compared with the experimental data in the literature. The selected hydrocarbon molecules were 3-pentanone, 1-hexanol, benzene, 3-methylphenol and 2-hydroxy-5-methylbenzaldehyde. The calculated results of the hydrocarbon molecules are in good agreement with the data in the literature. These results confirm that the solubilities of ginger bioactives can be predicted using the COSMO-RS method. The solubilities of the ginger bioactives are lower than 0.0001 at temperatures lower than 130 °C. At 130 to 200 °C, the solubilities increase dramatically with the highest being 6-shogaol, which is 0.00037 mole fraction, and the lowest is 10-gingerol, which is 0.000039 mole fraction at 200 °C.

  18. Prediction of solubilities for ginger bioactive compounds in hot water by the COSMO-RS method

    International Nuclear Information System (INIS)

    Jaapar, Syaripah Zaimah Syed; Iwai, Yoshio; Morad, Noor Azian

    2013-01-01

    The solubilities in water of four main ginger bioactives, 6-gingerol, 6-shogaol, 8-gingerol and 10-gingerol, were predicted using a conductor-like screening model for real solvent (COSMO-RS) calculations. This study was conducted since no experimental data are available for ginger bioactive solubilities in hot water. The σ-profiles of these selected molecules were calculated using Gaussian software and the solubilities were calculated using the COSMO-RS method. The solubilities of these ginger bioactives were calculated at 50 to 200 °C. In order to validate the accuracy of the COSMO-RS method, the solubilities of five hydrocarbon molecules were calculated using the COSMO-RS method and compared with the experimental data in the literature. The selected hydrocarbon molecules were 3-pentanone, 1-hexanol, benzene, 3-methylphenol and 2-hydroxy-5-methylbenzaldehyde. The calculated results of the hydrocarbon molecules are in good agreement with the data in the literature. These results confirm that the solubilities of ginger bioactives can be predicted using the COSMO-RS method. The solubilities of the ginger bioactives are lower than 0.0001 at temperatures lower than 130 °C. At 130 to 200 °C, the solubilities increase dramatically with the highest being 6-shogaol, which is 0.00037 mole fraction, and the lowest is 10-gingerol, which is 0.000039 mole fraction at 200 °C.

  19. Synthesis, characterization and fluorescent properties of water-soluble glycopolymer bearing curcumin pendant residues.

    Science.gov (United States)

    Zhang, Haisong; Yu, Meng; Zhang, Hailei; Bai, Libin; Wu, Yonggang; Wang, Sujuan; Ba, Xinwu

    2016-08-01

    Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1 and P2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV-Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymer P2 with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine.

  20. A facile physical approach to make chitosan soluble in acid-free water.

    Science.gov (United States)

    Fu, Yinghao; Xiao, Congming

    2017-10-01

    We changed the situation that chitosan was only dissolved in diluted acid through mild physical treatment. In viewing of the usual methods to modify chitosan are chemical ones, we established the approach by using a water-soluble chitosan derivative as the model polymer. Its water-solubility was modulated via changing the concentration of solution and varying the precipitants. Such a physical method was adopted to treat chitiosan. One gram chitosan was dissolved in a mixture of 100mL 10% acetic acid and 50mL methanol, and then precipitated from a precipitant consisted of 10mL ethanol and 90mL acetate ester. The treated chitosan became soluble in acid-free water completely, and its solubility was 8.02mg/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Tar removal from biosyngas in the biomass gasification process. (Liquid + liquid) equilibrium {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)}

    International Nuclear Information System (INIS)

    Bassil, Georgio; Mokbel, Ilham; Abou Naccoul, Ramy; Stephan, Juliette; Jose, Jacques; Goutaudier, Christelle

    2012-01-01

    Highlights: ► (Liquid + liquid) equilibria at atmospheric pressure. ► Solubility of benzene (or toluene or phenol) in paraxylene at (303 to 343) K. ► Solubility of benzene (or toluene or phenol) in methyl palmitate or methyl hexadecanoate at (303 to 343) K. ► Correlation of LLE using NRTL model. - Abstract: Tar is generated in the process by the condensation of the gas resulting from biomass gasification. The objective of this work is a contribution to the database on thermodynamic quantity which will be useful at the operation of tar removal from aqueous medium. With this aim, (liquid + liquid) equilibrium of {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)} was studied at temperatures (303.2, 323.2, and 343.2) K. The data obtained were correlated with the non-random two-liquid (NRTL) model.

  2. Amelioration of radiation induced oxidative stress using water soluble chitosan produced by Aspergillus niger

    International Nuclear Information System (INIS)

    EL-Sonbaty, S.M.; Swailam, H.M.; Noaman, E.

    2012-01-01

    Chitosan is a natural polysaccharide synthesized by a great number of living organisms and considered as a source of potential bioactive material and has many biological applications which are greatly affected by its solubility in neutral ph. In this study low molecular weight water soluble chitosan was prepared by chemical degradation of chitosan produced by Aspergillus niger using H 2 O 2 . Chitosan chemical structure was detected before and after treatment using FTIR spectrum, and its molecular weight was determined by its viscosity using viscometer. Its antioxidant activity against gamma radiation was evaluated in vivo using rats. Rats were divided into 4 groups; group 1: control, group 2: exposed to acute dose of gamma radiation (6 Gy), group 3: received water soluble chitosan, group 4: received water soluble chitosan then exposed to gamma radiation as group 2. Gamma radiation significantly increased malonaldehyde, decreased glutathione concentration, activity of superoxide dismutase, catalase, and glutatione peroxidase, while significantly increase the activity of alanine transferase, aspartate transferase, urea and creatinine concentration. Administration of water soluble chitosan has ameliorated induced changes caused by gamma radiation. It could be concluded that water soluble chitosan by scavenging free radicals directly or indirectly may act as a potent radioprotector against ionizing irradiation.

  3. 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

  4. Solubility of hydrogen in water in a broad temperature and pressure range

    International Nuclear Information System (INIS)

    Baranenko, V.I.; Kirov, V.S.

    1989-01-01

    In the coolant of water-water reactors, as a result of radiolytic decomposition of water and chemical additives (hydrazine and ammonia) and saturation of the make-up water of the first loop with free hydrogen in order to suppress radiolysis, 30-60 ml/kg of hydrogen is present in normal conditions. On being released from the water, it is free to accumulate in micropores of the metals, resulting in hydrogen embrittlement; gas accumulates in stagnant zones, with deterioration in heat transfer in the first loop and corresponding difficulty in the use of the reactor and the whole reactor loop. To determine the amount of free hydrogen and hydrogen dissolved in water in different elements of the first loop, it is necessary to know the limiting solubility of hydrogen in water at different temperatures and pressures, and also to have the corresponding theoretical dependences. The experimental data on the solubility of hydrogen in water are nonsystematic and do not cover the parameter ranges of modern nuclear power plants (P = 10-30 MPa, T = 260-370C). Therefore, the aim of the present work is to establish a well-founded method of calculating the limiting solubility of hydrogen in water and, on this basis, to compile tables of the limiting solubility of hydrogen in water at pressures 0.1-50 MPa and temperatures 0-370C

  5. 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

  6. Kinetics of proton migration in liquid water.

    Science.gov (United States)

    Chen, Hanning; Voth, Gregory A; Agmon, Noam

    2010-01-14

    We have utilized multistate empirical valence bond (MS-EVB3) simulations of protonated liquid water to calculate the relative mean-square displacement (MSD) and the history-independent time correlation function, c(t), of the hydrated proton center of excess charge (CEC) with respect to the water molecule on which it has initially resided. The MSD is nonlinear for the first 15 ps, suggesting that the relative diffusion coefficient increases from a small value, D(0), at short separations to its larger bulk value, D(infinity), at large separations. With the ensuing distance-dependent diffusion coefficient, D(r), the time dependence of both the MSD and c(t) agrees quantitatively with the solution of a diffusion equation for reversible geminate recombination. This suggests that the relative motion of the CEC is not independent from the nearby water molecules, in agreement with theoretical and experimental observations that large water clusters participate in the mechanism of proton mobility.

  7. Removal of Water-Soluble Extractives Improves the Enzymatic Digestibility of Steam-Pretreated Softwood Barks.

    Science.gov (United States)

    Frankó, Balázs; Carlqvist, Karin; Galbe, Mats; Lidén, Gunnar; Wallberg, Ola

    2018-02-01

    Softwood bark contains a large amounts of extractives-i.e., soluble lipophilic (such as resin acids) and hydrophilic components (phenolic compounds, stilbenes). The effects of the partial removal of water-soluble extractives before acid-catalyzed steam pretreatment on enzymatic digestibility were assessed for two softwood barks-Norway spruce and Scots pine. A simple hot water extraction step removed more than half of the water-soluble extractives from the barks, which improved the enzymatic digestibility of both steam-pretreated materials. This effect was more pronounced for the spruce than the pine bark, as evidenced by the 30 and 11% glucose yield improvement, respectively, in the enzymatic digestibility. Furthermore, analysis of the chemical composition showed that the acid-insoluble lignin content of the pretreated materials decreased when water-soluble extractives were removed prior to steam pretreatment. This can be explained by a decreased formation of water-insoluble "pseudo-lignin" from water-soluble bark phenolics during the acid-catalyzed pretreatment, which otherwise results in distorted lignin analysis and may also contribute to the impaired enzymatic digestibility of the barks. Thus, this study advocates the removal of extractives as the first step in the processing of bark or bark-rich materials in a sugar platform biorefinery.

  8. High pressure solubility data of carbon dioxide in (tri-iso-butyl(methyl)phosphonium tosylate + water) systems

    Energy Technology Data Exchange (ETDEWEB)

    Ventura, Sonia P.M. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Pauly, Jerome; Daridon, Jean L. [Laboratoire Haute Pression Centre Universitaire de Recherche Scientifique, Universite de Pau, Avenue de l' Universite, 64000 Pau (France); Lopes da Silva, J.A.; Marrucho, Isabel M. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Dias, Ana. M.A. [IBB-Instituto de Biotecnologia e Bioengenharia, Centro de Engenharia Biologica, Universidade do Minho, Campus de Gualtar, 4710-553 Braga (Portugal); Coutinho, Joao A.P. [CICECO, Departamento de Quimica, Universidade de Aveiro, 3810-193 Aveiro (Portugal)], E-mail: jcoutinho@ua.pt

    2008-08-15

    Ionic liquids are attracting great attention nowadays due to their interesting properties which make them useful in a broad range of applications including reaction media or separation/capture of environmentally hazardous gases such as carbon dioxide. In many cases, for practical and/or economical reasons, the use of aqueous solutions of ILs would be preferable to their use as pure compounds. In this work, high pressure equilibrium data for the {l_brace}carbon dioxide (CO{sub 2}) + tri-iso-butyl(methyl)phosphonium tosylate [iBu{sub 3}MeP][TOS] + water system were measured at temperatures ranging from (276 to 370) K and pressures up to 100 MPa. Measurements were performed using a high-pressure cell with a sapphire window that allows direct observation of the liquid-vapour transition. Mixtures with different IL concentrations were studied in order to check the influence of the amount of IL on the solubility of CO{sub 2} in the aqueous mixture. The results show that the presence of IL enhances the solubility of CO{sub 2} in the (IL + water) system revealing a salting-in effect of the IL on the solubility of CO{sub 2}. The appearance of a three phase region was observed for IL concentrations higher than 4 mol% of IL in water when working at pressures between 4 and 8 MPa and temperatures between (280 and 305) K. In this range, the upper limit of the VLE region observed is shown to increase with the temperature being almost independent of the IL initial concentration in the mixture.

  9. Tainting by short-term exposure of Atlantic salmon to water soluble petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Ackman, R.G.; Heras, H.

    1992-01-01

    Experiments were conducted to examine the extent of tainting of salmon by exposure to the soluble fraction of petroleum hydrocarbons. The experiments were conducted on Atlantic salmon in tanks containing seawater artificially contaminated at three different concentrations with the soluble fraction of a North Sea crude. The salmon flesh was analyzed by gas chromatography and taste tests were conducted on cooked salmon samples to determine the extent of tainting. Salmon in control tanks with uncontaminated seawater had muscle accumulations of total hydrocarbons of ca 1 ppM. The muscle accumulations of total hydrocarbons in the salmon were 13.5 ppM, 25.6 ppM, and 31.3 ppM for water soluble fraction concentrations of 0.45, 0.87, and 1.54 ppM respectively. The threshold for taint was clearly inferred to be less than 0.45 ppM of water soluble fraction. 18 refs., 2 figs

  10. Effect of water soluble carrier on dissolution profiles of diclofenac sodium.

    Science.gov (United States)

    Cwiertnia, Barbara

    2013-01-01

    Pharmaceutical aviailability of diclofenac sodium from solid dispersions of PEG 6000 have been studied in comparison to those of the corresponding physical mixtures and pure diclofenac sodium. The diclofenac sodium is poorly water soluble drug. The properties of diclofenac sodium-PEG 6000 solid dispersions have been determined by the methods of differential scanning calorimetry (DSC), X-ray diffraction and scanning electron microscopy (SEM). The effect of PEG 6000 on the solubility of selected diclofenac sodium dispersions has been studied. The solubility of diclofenac sodium from its solid dispersion has been found to increase in the presence of PEG 6000.

  11. Enhancement of solubility of poorly water soluble anti hypertensive drug by nanosizing approach

    Directory of Open Access Journals (Sweden)

    Divyesh Thakar

    2012-01-01

    Full Text Available The objective of this research study was to optimize formulation and process variables affecting characteristic of nanosuspension in bead milling process. In this study, the practically water-insoluble telmisartan was nanoground by using top down method i.e. media milling method. Here the media used is ZnO 2 beads. A variety of surface active agents were tested for their stabilizing effects. Formulation factors evaluated were ratio of polymer to drug, whereas process parameters were milling time and concentration of ZnO 2 beads. Different concentration of stabilizers such as poloxamer 188, poloxamer 407, HPMC E 15, PVP K30 and combination of stabilizers were used for preparation of telmisartan nanosuspension. Responses measured in this study include particle size measurement, particle size distribution and zeta potential.

  12. Preparation of water-soluble carbon nanotubes using a pulsed streamer discharge in water

    International Nuclear Information System (INIS)

    Imasaka, Kiminobu; Suehiro, Junya; Kanatake, Yusuke; Kato, Yuki; Hara, Masanori

    2006-01-01

    A novel technique for the preparation of water-soluble carbon nanotubes was demonstrated using a pulsed streamer discharge generated in water. The technique involved chemical reactions between radicals generated by the pulsed streamer discharge and carbon nanotubes. The pulsed streamer-treated carbon nanotubes were homogeneously dispersed and well solubilized in water for a month or longer. The mechanism of solubilization of carbon nanotubes by the pulsed streamer discharge is discussed based on FTIR spectroscopy and optical emission spectra measurements. FTIR spectroscopy revealed that -OH groups, which are known to impart a hydrophilic nature to carbon material, were introduced on the carbon nanotube surface. Optical emission spectra from the pulsed streamer plasma showed that highly oxidative O * and H * radicals were generated in water. These results suggest that the functionalization of the carbon nanotube surface by -OH group can be attributed to the O * and H * radicals. An advantage of the proposed method is that there is no need for any chemical agents or additives for solubilization. Chemical agents for solubilization are generated from the water itself by the electrochemical reactions induced by the pulsed streamer discharge

  13. Water solubility of synthetic pyrope at high temperature and pressure up to 12GPa

    Science.gov (United States)

    Huang, S.; Chen, J.

    2012-12-01

    Water can be incorporated into normally anhydrous minerals as OH- defects and transported into the mantle. Its existence in the mantle may affect property of minerals, such as elasticity, electrical conductivity and rheological properties. As the secondary mineral in the mantle, garnet has not been extensively studied for its water solubility and there is discrepancies among the existing experiments on the water solubility in the garnet change at pressures and temperatures. Geiger et al., 1991 investigated water content in synthetic pyrope and concluded 0.02wt% to 0.07wt% OH- substitution. Lu et al., 1997 found 198ppm water in the Dora Miara pyrope at 100Kbar and 1000°C. Withers et al., 1998 claimed that water solubility in pyrope reached 1000ppm at 5GPa and then decreased as pressure increasing; above 7GPa, no water was detected. Mookherjee et al., 2009 also explored pyrope-rich garnet, which contains water up to 0.1%wt at 5-9GPa and temperatures 1373K-1473K. Here we report a study of water solubility of synthetic single crystal pyrope at pressures 4-12GPa and temperature 1000°C. Single crystals of pyrope were synthesized using multi-anvil press and water contents in these samples were measured using FTIR. We have observed OH- peak at 3650 cm-1 along this pressure range, although Withers, 1998 reported water contents decrease to undetectable level above 7GPa. Water solubility in pyrope will be reported as a function of pressure up to 12 GPa at 1000°C.

  14. Thermodynamic analysis of chromium solubility data in liquid lithium containing nitrogen: Comparison between experimental data and computer simulation

    International Nuclear Information System (INIS)

    Krasin, Valery P.; Soyustova, Svetlana I.

    2015-01-01

    The mathematical formalism for description of solute interactions in dilute solution of chromium and nitrogen in liquid lithium have been applied for calculating of the temperature dependence of the solubility of chromium in liquid lithium with the various nitrogen contents. It is shown that the derived equations are useful to provide understanding of a relationship between thermodynamic properties and local ordering in the Li–Cr–N melt. Comparison between theory and data reported in the literature for solubility of chromium in nitrogen-contaminated liquid lithium, was allowed to explain the reasons of the deviation of the experimental semi-logarithmic plot of chromium content in liquid lithium as a function of the reciprocal temperature from a straight line. - Highlights: • The activity coefficient of chromium in ternary melt can be obtained by means of integrating the Gibbs–Duhem equation. • In lithium with the high nitrogen content, the dependence of a logarithm of chromium solubility as a function of the reciprocal temperature has essentially nonlinear character. • At temperatures below a certain threshold, the process of dissolution of chromium in lithium will be controlled by the equilibrium concentration of nitrogen required for the formation of ternary nitride Li_9CrN_5at a given temperature.

  15. Carbonate compensation depth: relation to carbonate solubility in ocean waters.

    Science.gov (United States)

    Ben-Yaakov, S; Ruth, E; Kaplan, I R

    1974-05-31

    In situ calcium carbonate saturometry measurements suggest that the intermediate water masses of the central Pacific Ocean are close to saturation with resppect to both calcite and local carbonate sediment. The carbonate compensation depth, located at about 3700 meters in this area, appears to represent a depth above which waters are essentially saturated with respect to calcite and below which waters deviate toward undersaturation with respect to calcite.

  16. Water in Room Temperature Ionic Liquids

    Science.gov (United States)

    Fayer, Michael

    2014-03-01

    Room temperature ionic liquids (or RTILs, salts with a melting point below 25 °C) have become a subject of intense study over the last several decades. Currently, RTIL application research includes synthesis, batteries, solar cells, crystallization, drug delivery, and optics. RTILs are often composed of an inorganic anion paired with an asymmetric organic cation which contains one or more pendant alkyl chains. The asymmetry of the cation frustrates crystallization, causing the salt's melting point to drop significantly. In general, RTILs are very hygroscopic, and therefore, it is of interest to examine the influence of water on RTIL structure and dynamics. In addition, in contrast to normal aqueous salt solutions, which crystallize at low water concentration, in an RTIL it is possible to examine isolated water molecules interacting with ions but not with other water molecules. Here, optical heterodyne-detected optical Kerr effect (OHD-OKE) measurements of orientational relaxation on a series of 1-alkyl-3-methylimidazolium tetrafluoroborate RTILs as a function of chain length and water concentration are presented. The addition of water to the longer alkyl chain RTILs causes the emergence of a long time bi-exponential orientational anisotropy decay. Such decays have not been seen previously in OHD-OKE experiments on any type of liquid and are analyzed here using a wobbling-in-a-cone model. The orientational relaxation is not hydrodynamic, with the slowest relaxation component becoming slower as the viscosity decreases for the longest chain, highest water content samples. The dynamics of isolated D2O molecules in 1-butyl-3-methylimidazolium hexafluorophosphate (BmImPF6) were examined using two dimensional infrared (2D IR) vibrational echo spectroscopy. Spectral diffusion and incoherent and coherent transfer of excitation between the symmetric and antisymmetric modes are examined. The coherent transfer experiments are used to address the nature of inhomogeneous

  17. 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.

  18. Comparison of water sorption and solubility of Acropars and Meliodent heat cure acrylic resins

    Directory of Open Access Journals (Sweden)

    Golbidi F

    2006-06-01

    Full Text Available Background and Aim: Water sorption and solubility are important properties of acrylic resins. Denture base acrylic resins have low solubility. This solubility results from the leaching out of unreacted monomer and water soluble additives into the oral fluids. The solubility of denture bases can cause oral soft tissue reactions. In addition, water absorbed into this material acts as a plasticizer and decreases the mechanical properties such as hardness, transverse strength, fatigue limit and also can change the color and dimensional stability. The aim of this study was to compare the water sorption and solubility of Acropars and Meliodent heat cure acrylic resins. Materials and Methods: This experimental study was performed on the basis of ADA specification No.12 and ISO No.1567 and standards NO: 2571 of Institute of Standards & Industrial Research of Iran. Six disc form samples of each acrylic resin were prepared, with the dimension of 50×0.5 mm. After desiccating, the samples were kept in an oven for 24 hours and weighed. Then they were immersed in water, kept in oven for 7 days and weighed again. After this phase, the samples were carried to a dessicator, for 24 hours and kept in an oven for drying and were weighed for the third time. Data were analyzed with Mann Whitney and one sample t-test. P<0.05 was considered as the limit of significance. Results: Water sorption mean values were 30.5±0.1 µg/mm3 or 0.76±0.01 mg/cm2 for Meliodent samples and 30.7±0.87 µg/mm3 or 0.77±0.009 mg/cm2 for Acropars samples. No significant difference was observed in water sorption of these two materials (P=0.9. Meliodent acrylic resin showed lower solubility (1.7±0.097 µg/mm3 or 0.042±0.001 mg/cm2 than Acropars acrylic resin (2.5±0.13 µg/mm3 or 0.062±0.001 mg/cm2 (P=0.002. Conclusion: Acropars heat cure acrylic resin matched well with the requirements of the international standards for water sorption, but its solubility was not favorable. This problem

  19. Salinity impacts on water solubility and n-octanol/water partition coefficients of selected pesticides and oil constituents.

    Science.gov (United States)

    Saranjampour, Parichehr; Vebrosky, Emily N; Armbrust, Kevin L

    2017-09-01

    Salinity has been reported to influence the water solubility of organic chemicals entering marine ecosystems. However, limited data are available on salinity impacts for chemicals potentially entering seawater. Impacts on water solubility would correspondingly impact chemical sorption as well as overall bioavailability and exposure estimates used in the regulatory assessment. The pesticides atrazine, fipronil, bifenthrin, and cypermethrin, as well as the crude oil constituent dibenzothiophene together with 3 of its alkyl derivatives, all have different polarities and were selected as model compounds to demonstrate the impact of salinity on their solubility and partitioning behavior. The n-octanol/water partition coefficient (K OW ) was measured in both distilled-deionized water and artificial seawater (3.2%). All compounds had diminished solubility and increased K OW values in artificial seawater compared with distilled-deionized water. A linear correlation curve estimated salinity may increase the log K OW value by 2.6%/1 log unit increase in distilled water (R 2  = 0.97). Salinity appears to generally decrease the water solubility and increase the partitioning potential. Environmental fate estimates based on these parameters indicate elevated chemical sorption to sediment, overall bioavailability, and toxicity in artificial seawater. These dramatic differences suggest that salinity should be taken into account when exposure estimates are made for marine organisms. Environ Toxicol Chem 2017;36:2274-2280. © 2017 SETAC. © 2017 SETAC.

  20. Influence of the temperature on the (liquid + liquid) phase equilibria of (water + 1-propanl + linalool or geraniol)

    International Nuclear Information System (INIS)

    Wan, Li; Li, Hengde; Huang, Cheng; Feng, Yuqing; Chu, Guoqiang; Zheng, Yuying; Tan, Wei; Qin, Yanlin; Sun, Dalei; Fang, Yanxiong

    2017-01-01

    Highlights: • Ternary LLEs containing linalool and geraniol are presented. • Distribution ratios of 1-propanol in the mixtures are examined. • Influence of the temperature on the LLE is studied. • The LLE data were correlated using the NRTL and UNIQUAC models. - Abstract: Linalool and geraniol are the primary components of rose oil, palmarosa oil, and citronella oil and many other essential oils, and two important compounds used in the flavour and fragrance, cosmetic or pharmaceutical industries. Phase equilibria (LLE, VLE, solubility, etc.) and related thermodynamic properties of a mixture are essential in the processes design and control of mass transfer process. In this work, experimental (liquid + liquid) equilibria data of the systems (water + 1-propanl + linalool) and (water + 1-propanl + geraniol) are presented. The (liquid + liquid) equilibria of both systems were determined with a tie-line method at T = (283.15, 298.15 and 313.15) K under atmospheric pressure. The well-known Hand, Bachman and Othmer–Tobias equations were used to test the reliability of the experimental values. The influence of the temperature on the (liquid + liquid) phase equilibria of the mixtures, the binodal curves and distribution ratios of 1-propanl are shown and discussed. Moreover, the NRTL and UNIQUAC models were applied to fit the data for both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. Furthermore, the ternary systems could be represented using the binary parameters of the thermodynamic model with a function of temperature.

  1. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    NARCIS (Netherlands)

    Baker, M.B.; Albertazzi, L.; Voets, Ilja K.; Leenders, C.M.A.; Palmans, A.R.A.; Pavan, G.M.; Meijer, E. W.

    2015-01-01

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers:

  2. Kinetics of Acid Hydrolysis of Water-Soluble Spruce O-Acetyl Galactoglucomannans

    NARCIS (Netherlands)

    Xu, C.; Pranovich, A.; Vahasalo, L.; Hemming, J.; Holmbom, B.; Schols, H.A.; Willfor, S.

    2008-01-01

    Water-soluble O-acetyl galactoglucomannan (GGM) is a softwood-derived polysaccharide, which can be extracted on an industrial scale from wood or mechanical pulping waters and now is available in kilogram scale for research and development of value-added products. To develop applications of GGM,

  3. Steel corrosion products solubility under conditions simulating various water chemistry parameters in power plants

    International Nuclear Information System (INIS)

    Slobodov, A.A.; Kritskij, V.G.; Zarembo, V.I.; Puchkov, L.V.

    1988-01-01

    To simulate construction material corrosion product mass transfer model in power plant circuits calculation of iron oxide and hydroxide solubility, depending on water chemistry parameters: temperature, pH-value, content of dissolved in water hydrogen and oxygen, is carried out

  4. Structural investigation of water-soluble polysaccharides extracted from the fruit bodies of Coprinus comatus

    NARCIS (Netherlands)

    Li, Bo; Dobruchowska, Justyna M.; Gerwig, Gerrit J.; Dijkhuizen, Lubbert; Kamerling, Johannis P.

    2013-01-01

    Water-soluble polysaccharide material, extracted from the stipes of the fruit bodies of Coprinus comatus by hot water, was fractionated by sequential weak anion-exchange and size-exclusion chromatography. The relevant fractions were subjected to structural analysis, including (D/L)

  5. Water-soluble carbon nanotube compositions for drug delivery and medicinal applications

    Science.gov (United States)

    Tour, James M.; Lucente-Schultz, Rebecca; Leonard, Ashley; Kosynkin, Dmitry V.; Price, Brandi Katherine; Hudson, Jared L.; Conyers, Jr., Jodie L.; Moore, Valerie C.; Casscells, S. Ward; Myers, Jeffrey N.; Milas, Zvonimir L.; Mason, Kathy A.; Milas, Luka

    2014-07-22

    Compositions comprising a plurality of functionalized carbon nanotubes and at least one type of payload molecule are provided herein. The compositions are soluble in water and PBS in some embodiments. In certain embodiments, the payload molecules are insoluble in water. Methods are described for making the compositions and administering the compositions. An extended release formulation for paclitaxel utilizing functionalized carbon nanotubes is also described.

  6. Autodissociation of a water molecule in liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Geissler, Phillip L.; Dellago, Christoph; Chandler, David; Hutter, Jurg; Parrinello, Michele

    2000-04-01

    The dissociation of a water molecule in liquid water is the fundamental event in acid-base chemistry, determining the pH of water.Because the microscopic dynamics of this autodissociation are difficult to probe, both by experiment and by computer simulation, its mechanism has been unknown. Here we report several autodissociation trajectories generated by ab initio molecular dynamics [1]. These trajectories, which were harvested using transition path sampling [2-4], reveal the mechanism for the first time. Rare fluctuations in solvation energies destabilize an oxygen-hydrogen bond. Through the transfer of one or more protons along a hydrogen bond.

  7. Temperature-dependent photoluminescence of water-soluble quantum dots for a bioprobe

    International Nuclear Information System (INIS)

    Liu Tiancai; Huang Zhenli; Wang Haiqiao; Wang Jianhao; Li Xiuqing; Zhao Yuandi; Luo Qingming

    2006-01-01

    The photoluminescence of water-soluble CdSe/ZnS core/shell quantum dots is found to be temperature-dependent: as temperature arising from 280 K to 351 K, the photoluminescence declines with emission peak shifting towards the red at a rate of ∼0.11 nm K -1 . And the studies show that the photoluminescence of water-soluble CdSe/ZnS quantum dots with core capped by a thinner ZnS shell is more sensitive to temperature than that of ones with core capped by a thicker one. That is, with 50% decrement of the quantum yield the temperature of the former need to arise from 280 K to 295 K, while the latter requires much higher temperature (315.6 K), which means that the integrality of shell coverage is a very important factor on temperature-sensitivity to for the photoluminescence of water-soluble CdSe/ZnS quantum dots. Moreover, it is found that the water-soluble CdSe quantum dots with different core sizes, whose cores are capped by thicker ZnS shells, possess almost the same sensitivity to the temperature. All of the studies about photoluminescence temperature-dependence of water-soluble CdSe/ZnS core/shell quantum dots show an indispensable proof for their applications in life science

  8. Water soluble {2-[3-(diethylamino)phenoxy]ethoxy} substituted zinc(II) phthalocyanine photosensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Çakır, Dilek [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Göl, Cem [Gebze Institute of Technology, Department of Chemistry, PO Box 141, Gebze, 41400, Kocaeli (Turkey); Çakır, Volkan [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Durmuş, Mahmut [Gebze Institute of Technology, Department of Chemistry, PO Box 141, Gebze, 41400, Kocaeli (Turkey); Bıyıklıoğlu, Zekeriya, E-mail: zekeriya_61@yahoo.com [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey); Kantekin, Halit [Department of Chemistry, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2015-03-15

    The new peripherally and non-peripherally tetra-{2-[3-(diethylamino)phenoxy] ethoxy} substituted zinc phthalocyanines (2a and 3a) were synthesized by cyclotetramerization of phthalonitrile derivatives (2 and 3). 2-[3-(diethylamino)phenoxy] ethoxy group was chosen as substituent because the quaternization of the diethylamino functionality on the structure of this group produced water soluble zinc phthalocyanines (2b and 3b). The water solubility is very important for many different applications such as photosensitizers in the photodynamic therapy of cancer because the water soluble photosensitizers can be injected directly to the body and they can transport to cancer cells through blood stream. The new compounds were characterized by using elemental analysis, UV–vis, IR, {sup 1}H NMR, {sup 13}C NMR and mass spectroscopies. The photophysical and photochemical properties of these novel photosensitizer compounds were examined in DMSO (both non-ionic and ionic complexes) and in PBS (for ionic complexes) solutions. The investigation of these properties is very important for the usage of the compounds as photosensitizers for PDT because determination of these properties is the first stage of potential of the compounds as photosensitizers. The bovine serum albumin (BSA) and DNA binding behaviour of the studied water soluble zinc (II) phthalocyanines were also investigated in PBS solutions for the determination of biological activity of these compounds. - Highlights: • Synthesis of water soluble zinc phthalocyanines. • Photophysical and photochemical properties for phthalocyanines. • Photodynamic therapy studies.

  9. The role of vitamins in the diet of the elderly II. Water-soluble vitamins

    Directory of Open Access Journals (Sweden)

    Csapó J.

    2017-10-01

    Full Text Available Following a presentation of humans’ water-soluble vitamin requirements, the authors will discuss in detail the role these vitamins play in human organism and outline those major biochemical processes that are negatively affected in the body in case of vitamin deficiency. They point out that in the elderly population of developed countries cases of water-soluble vitamin deficiency are extremely rare and they are due to the lack of dietary vitamin, but mostly to the vitamin being released from its bindings, the difficulty of free vitamin absorption, gastrointestinal problems, medication, and often alcoholism. Among water-soluble vitamins, B12 is the only one with a sufficient storage level in the body, capable of preventing deficiency symptoms for a long period of time in cases of vitamin-deficient nutrition. Each type of vitamin is dealt with separately in discussing the beneficial outcomes of their overconsumption regarding health, while the authors of the article also present cases with contradictory results. Daily requirements are set forth for every water-soluble vitamin and information is provided on the types of nutrients that help us to the water-soluble vitamins essential for the organism.

  10. Water Soluble Vitamins Enhance the Growth of Microorganisms in Peripheral Parenteral Nutrition Solutions.

    Science.gov (United States)

    Omotani, Sachiko; Tani, Katsuji; Nagai, Katsuhito; Hatsuda, Yasutoshi; Mukai, Junji; Myotoku, Michiaki

    2017-01-01

    Peripheral parenteral nutrition (PPN) solutions contain amino acids, glucose, and electrolytes, with or without some water soluble vitamins. Peripheral venous catheters are one of the causes of catheter related blood stream infection (CRBSI), which requires infection control. In Japan, PPN solutions have rarely been prepared under aseptic conditions. However, in recent years, the necessity of adding vitamins to infusions has been reported. Therefore, we investigated the effects of water soluble vitamins on growth of microorganisms in PPN solutions. AMINOFLUID ® (AF), BFLUID ® (BF), PARESAFE ® (PS) and PAREPLUS ® (PP) PPN solutions were used. Water soluble vitamins contained in PP were also used. Causative microorganisms of CRBSI were used. Staphylococcus epidermidis decreased after 24 hours or 48 hours in all solutions. On the other hand, Escherichia coli , Serratia marcescens , Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans increased, especially in PP. When each water soluble vitamin was added to BF and PS, growth of S. aureus was greater in solutions that contained nicotinamide than in solutions that contained other vitamins. As for C. albicans , they grew in all test solutions. C. albicans grew especially well in solutions that contained biotin. When commercial amino acids and glucose solutions with electrolytes are administered, in particular those containing multivitamins or water soluble vitamins, efforts to control infection must be taken to prevent proliferation of microorganisms.

  11. Teratogenicity and metabolism of water-soluble forms of vitamin A in the pregnant rat

    International Nuclear Information System (INIS)

    Gunning, D.B.; Barua, A.B.; Olson, J.A.

    1990-01-01

    Retinoyl β-glucuronide, unlike retinoic acid, has been shown to be non-teratogenic when administered orally, even in large doses, to pregnant rats. The degree to which water-solubility is associated with low teratogenicity is not known. Other water-soluble forms of vitamin A have now been synthesized in our laboratory and are being evaluated for teratogenicity. New water-soluble forms of vitamin A were administered orally to pregnant Sprague-Dawley rats in a single dose of 0.35 mmole/kg bw on day 8 of gestation. On day 19, the dams were sacrificed and the litters were examined. Control animals received either vehicle only or an equivalent dose of all-trans retinoic acid. Maternal and fetal tissues were taken and analyzed by HPLC for vitamin A metabolites. In another experiment, a large single oral dose of the radiolabelled water-soluble compound was administered on day 10. At either 30 minutes or 1 hour after the dose, dams were sacrificed and the embryos analyzed both for radioactivity and for specific metabolites. In contrast to retinoyl β-glucuronide, retinoyl β-glucose is highly teratogenic under identical conditions. Thus, water-solubility does not seem to be the determining factor in the teratogenicity of retinoic acid conjugates

  12. Temperature-dependent photoluminescence of water-soluble quantum dots for a bioprobe

    Energy Technology Data Exchange (ETDEWEB)

    Liu Tiancai [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Huang Zhenli [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang Haiqiao [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang Jianhao [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Li Xiuqing [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Zhao Yuandi [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)]. E-mail: zydi@mail.hust.edu.cn; Luo Qingming [Key Laboratory of Biomedical Photonics of Ministry of Education - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2006-02-10

    The photoluminescence of water-soluble CdSe/ZnS core/shell quantum dots is found to be temperature-dependent: as temperature arising from 280 K to 351 K, the photoluminescence declines with emission peak shifting towards the red at a rate of {approx}0.11 nm K{sup -1}. And the studies show that the photoluminescence of water-soluble CdSe/ZnS quantum dots with core capped by a thinner ZnS shell is more sensitive to temperature than that of ones with core capped by a thicker one. That is, with 50% decrement of the quantum yield the temperature of the former need to arise from 280 K to 295 K, while the latter requires much higher temperature (315.6 K), which means that the integrality of shell coverage is a very important factor on temperature-sensitivity to for the photoluminescence of water-soluble CdSe/ZnS quantum dots. Moreover, it is found that the water-soluble CdSe quantum dots with different core sizes, whose cores are capped by thicker ZnS shells, possess almost the same sensitivity to the temperature. All of the studies about photoluminescence temperature-dependence of water-soluble CdSe/ZnS core/shell quantum dots show an indispensable proof for their applications in life science.

  13. Membrane Proteins Are Dramatically Less Conserved than Water-Soluble Proteins across the Tree of Life.

    Science.gov (United States)

    Sojo, Victor; Dessimoz, Christophe; Pomiankowski, Andrew; Lane, Nick

    2016-11-01

    Membrane proteins are crucial in transport, signaling, bioenergetics, catalysis, and as drug targets. Here, we show that membrane proteins have dramatically fewer detectable orthologs than water-soluble proteins, less than half in most species analyzed. This sparse distribution could reflect rapid divergence or gene loss. We find that both mechanisms operate. First, membrane proteins evolve faster than water-soluble proteins, particularly in their exterior-facing portions. Second, we demonstrate that predicted ancestral membrane proteins are preferentially lost compared with water-soluble proteins in closely related species of archaea and bacteria. These patterns are consistent across the whole tree of life, and in each of the three domains of archaea, bacteria, and eukaryotes. Our findings point to a fundamental evolutionary principle: membrane proteins evolve faster due to stronger adaptive selection in changing environments, whereas cytosolic proteins are under more stringent purifying selection in the homeostatic interior of the cell. This effect should be strongest in prokaryotes, weaker in unicellular eukaryotes (with intracellular membranes), and weakest in multicellular eukaryotes (with extracellular homeostasis). We demonstrate that this is indeed the case. Similarly, we show that extracellular water-soluble proteins exhibit an even stronger pattern of low homology than membrane proteins. These striking differences in conservation of membrane proteins versus water-soluble proteins have important implications for evolution and medicine. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. Water soluble {2-[3-(diethylamino)phenoxy]ethoxy} substituted zinc(II) phthalocyanine photosensitizers

    International Nuclear Information System (INIS)

    Çakır, Dilek; Göl, Cem; Çakır, Volkan; Durmuş, Mahmut; Bıyıklıoğlu, Zekeriya; Kantekin, Halit

    2015-01-01

    The new peripherally and non-peripherally tetra-{2-[3-(diethylamino)phenoxy] ethoxy} substituted zinc phthalocyanines (2a and 3a) were synthesized by cyclotetramerization of phthalonitrile derivatives (2 and 3). 2-[3-(diethylamino)phenoxy] ethoxy group was chosen as substituent because the quaternization of the diethylamino functionality on the structure of this group produced water soluble zinc phthalocyanines (2b and 3b). The water solubility is very important for many different applications such as photosensitizers in the photodynamic therapy of cancer because the water soluble photosensitizers can be injected directly to the body and they can transport to cancer cells through blood stream. The new compounds were characterized by using elemental analysis, UV–vis, IR, 1 H NMR, 13 C NMR and mass spectroscopies. The photophysical and photochemical properties of these novel photosensitizer compounds were examined in DMSO (both non-ionic and ionic complexes) and in PBS (for ionic complexes) solutions. The investigation of these properties is very important for the usage of the compounds as photosensitizers for PDT because determination of these properties is the first stage of potential of the compounds as photosensitizers. The bovine serum albumin (BSA) and DNA binding behaviour of the studied water soluble zinc (II) phthalocyanines were also investigated in PBS solutions for the determination of biological activity of these compounds. - Highlights: • Synthesis of water soluble zinc phthalocyanines. • Photophysical and photochemical properties for phthalocyanines. • Photodynamic therapy studies

  15. Soluble and insoluble pollutants in fog and rime water samples

    Czech Academy of Sciences Publication Activity Database

    Fišák, Jaroslav; Stoyanova, V.; Chaloupecký, Pavel; Řezáčová, Daniela; Tsacheva, Ts.; Kupenova, T.; Marinov, M.

    2009-01-01

    Roč. 4, Sp. Iss. 2 (2009), S123-S130 ISSN 1801-5395 R&D Projects: GA ČR GA205/09/1918; GA AV ČR 1QS200420562 Institutional research plan: CEZ:AV0Z30420517 Keywords : fog water * rime water * pollutant concentration Subject RIV: DG - Athmosphere Sciences, Meteorology

  16. Water Solubility of Plutonium and Uranium Compounds and Residues at TA-55

    International Nuclear Information System (INIS)

    Reilly, Sean Douglas; Smith, Paul Herrick; Jarvinen, Gordon D.; Prochnow, David Adrian; Schulte, Louis D.; DeBurgomaster, Paul Christopher; Fife, Keith William; Rubin, Jim; Worl, Laura Ann

    2016-01-01

    Understanding the water solubility of plutonium and uranium compounds and residues at TA-55 is necessary to provide a technical basis for appropriate criticality safety, safety basis and accountability controls. Individual compound solubility was determined using published solubility data and solution thermodynamic modeling. Residue solubility was estimated using a combination of published technical reports and process knowledge of constituent compounds. The scope of materials considered includes all compounds and residues at TA-55 as of March 2016 that contain Pu-239 or U-235 where any single item in the facility has more than 500 g of nuclear material. This analysis indicates that the following materials are not appreciably soluble in water: plutonium dioxide (IDC=C21), plutonium phosphate (IDC=C66), plutonium tetrafluoride (IDC=C80), plutonium filter residue (IDC=R26), plutonium hydroxide precipitate (IDC=R41), plutonium DOR salt (IDC=R42), plutonium incinerator ash (IDC=R47), uranium carbide (IDC=C13), uranium dioxide (IDC=C21), U 3 O 8 (IDC=C88), and uranium filter residue (IDC=R26). This analysis also indicates that the following materials are soluble in water: plutonium chloride (IDC=C19) and uranium nitrate (IDC=C52). Equilibrium calculations suggest that PuOCl is water soluble under certain conditions, but some plutonium processing reports indicate that it is insoluble when present in electrorefining residues (R65). Plutonium molten salt extraction residues (IDC=R83) contain significant quantities of PuCl 3 , and are expected to be soluble in water. The solubility of the following plutonium residues is indeterminate due to conflicting reports, insufficient process knowledge or process-dependent composition: calcium salt (IDC=R09), electrorefining salt (IDC=R65), salt (IDC=R71), silica (IDC=R73) and sweepings/screenings (IDC=R78). Solution thermodynamic modeling also indicates that fire suppression water buffered with a commercially-available phosphate

  17. Water Solubility of Plutonium and Uranium Compounds and Residues at TA-55

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, Sean Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Smith, Paul Herrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Jarvinen, Gordon D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Prochnow, David Adrian [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Schulte, Louis D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; DeBurgomaster, Paul Christopher [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Fife, Keith William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Rubin, Jim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Worl, Laura Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States

    2016-06-13

    Understanding the water solubility of plutonium and uranium compounds and residues at TA-55 is necessary to provide a technical basis for appropriate criticality safety, safety basis and accountability controls. Individual compound solubility was determined using published solubility data and solution thermodynamic modeling. Residue solubility was estimated using a combination of published technical reports and process knowledge of constituent compounds. The scope of materials considered includes all compounds and residues at TA-55 as of March 2016 that contain Pu-239 or U-235 where any single item in the facility has more than 500 g of nuclear material. This analysis indicates that the following materials are not appreciably soluble in water: plutonium dioxide (IDC=C21), plutonium phosphate (IDC=C66), plutonium tetrafluoride (IDC=C80), plutonium filter residue (IDC=R26), plutonium hydroxide precipitate (IDC=R41), plutonium DOR salt (IDC=R42), plutonium incinerator ash (IDC=R47), uranium carbide (IDC=C13), uranium dioxide (IDC=C21), U3O8 (IDC=C88), and uranium filter residue (IDC=R26). This analysis also indicates that the following materials are soluble in water: plutonium chloride (IDC=C19) and uranium nitrate (IDC=C52). Equilibrium calculations suggest that PuOCl is water soluble under certain conditions, but some plutonium processing reports indicate that it is insoluble when present in electrorefining residues (R65). Plutonium molten salt extraction residues (IDC=R83) contain significant quantities of PuCl3, and are expected to be soluble in water. The solubility of the following plutonium residues is indeterminate due to conflicting reports, insufficient process knowledge or process-dependent composition: calcium salt (IDC=R09), electrorefining salt (IDC=R65), salt (IDC=R71), silica (IDC=R73) and sweepings/screenings (IDC=R78). Solution thermodynamic modeling also indicates that fire suppression water buffered with a

  18. 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

  19. Solubility of water in fluorocarbons: Experimental and COSMO-RS prediction results

    International Nuclear Information System (INIS)

    Freire, Mara G.; Carvalho, Pedro J.; Santos, Luis M.N.B.F.; Gomes, Ligia R.; Marrucho, Isabel M.; Coutinho, Joao A.P.

    2010-01-01

    This work aims at providing experimental and theoretical information about the water-perfluorocarbon molecular interactions. For that purpose, experimental solubility results for water in cyclic and aromatic perfluorocarbons (PFCs), over the temperature range between (288.15 and 318.15) K, and at atmospheric pressure, were obtained and are presented. From the experimental solubility dependence on temperature, the partial molar solution and solvation thermodynamic functions such as Gibbs free energy, enthalpy and entropy were determined and are discussed. The process of dissolution of water in PFCs is shown to be spontaneous for cyclic and aromatic compounds. It is demonstrated that the interactions between the non-aromatic PFCs and water are negligible while those between aromatic PFCs and water are favourable. The COSMO-RS predictive capability was explored for the description of the water solubility in PFCs and others substituted fluorocompounds. The COSMO-RS is shown to be a useful model to provide reasonable predictions of the solubility values, as well as to describe their temperature and structural modifications dependence. Moreover, the molar Gibbs free energy and molar enthalpy of solution of water are predicted remarkably well by COSMO-RS while the main deviations appear for the prediction of the molar entropy of solution.

  20. Metastable liquid-liquid transition in a molecular model of water

    Science.gov (United States)

    Palmer, Jeremy C.; Martelli, Fausto; Liu, Yang; Car, Roberto; Panagiotopoulos, Athanassios Z.; Debenedetti, Pablo G.

    2014-06-01

    Liquid water's isothermal compressibility and isobaric heat capacity, and the magnitude of its thermal expansion coefficient, increase sharply on cooling below the equilibrium freezing point. Many experimental, theoretical and computational studies have sought to understand the molecular origin and implications of this anomalous behaviour. Of the different theoretical scenarios put forward, one posits the existence of a first-order phase transition that involves two forms of liquid water and terminates at a critical point located at deeply supercooled conditions. Some experimental evidence is consistent with this hypothesis, but no definitive proof of a liquid-liquid transition in water has been obtained to date: rapid ice crystallization has so far prevented decisive measurements on deeply supercooled water, although this challenge has been overcome recently. Computer simulations are therefore crucial for exploring water's structure and behaviour in this regime, and have shown that some water models exhibit liquid-liquid transitions and others do not. However, recent work has argued that the liquid-liquid transition has been mistakenly interpreted, and is in fact a liquid-crystal transition in all atomistic models of water. Here we show, by studying the liquid-liquid transition in the ST2 model of water with the use of six advanced sampling methods to compute the free-energy surface, that two metastable liquid phases and a stable crystal phase exist at the same deeply supercooled thermodynamic condition, and that the transition between the two liquids satisfies the thermodynamic criteria of a first-order transition. We follow the rearrangement of water's coordination shell and topological ring structure along a thermodynamically reversible path from the low-density liquid to cubic ice. We also show that the system fluctuates freely between the two liquid phases rather than crystallizing. These findings provide unambiguous evidence for a liquid-liquid transition in

  1. Gastrointestinal absorption of soluble uranium from drinking water. Published paper

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Singh, N.P.; Ruth, H.; Burleigh, D.

    1988-04-01

    This manuscript describes results of an experiment to determine the gastrointestinal absorption of uranium from drinking water in 12 health adults. Most of the uranium ingested was excreted in feces in the first 2 days following ingestion of the water. The absorption was the same for (234)U and (238)U for each subject. Absorption varied among subjects from -0.02% to 2.6%, with a mean of 0.6%. Low absorption may be due to concurrent ingestion of food

  2. Temperature and salt addition effects on the solubility behaviour of some phenolic compounds in water

    Energy Technology Data Exchange (ETDEWEB)

    Noubigh, Adel [Laboratoire de Physico-chimie des materiaux, IPEST, BP51, 2070 La MARSA (Tunisia)]. E-mail: Adel.anoubigh@ipest.rnu.tn; Abderrabba, Manef [Laboratoire de Physico-chimie des materiaux, IPEST, BP51, 2070 La MARSA (Tunisia); Provost, Elise [Laboratoire Chimie et procedes, ENSTA, 32 Rue de Boulevard Victor, 75739 Paris, Cedex 15 (France)

    2007-02-15

    Solubility-temperature dependence data for six phenolic compounds (PhC), contained in olive mill wastewater (OMWW), in water and in some chloride salts (KCl, NaCl, and LiCl) aqueous solutions have been presented and solution standard molar enthalpies ({delta}{sub sol} H {sup 0}) were determined using Van't Hoff plots. The temperature was varied from 293.15 K to 318.15 K. Solubility data were estimated using a thermostated reactor and HPLC analysis. It has been observed that solubility, in pure water and in aqueous chloride solutions, increases with increasing temperature. The salting-out LiCl > NaCl > KCl order obtained at 298.15 K is confirmed. Results were interpreted in terms of the salt hydration shells and the ability of the solute to form hydrogen-bond with water. The standard molar Gibbs free energies of transfer of PhC ({delta}{sub tr} G {sup 0}) from pure water to aqueous solutions of the chloride salts have been calculated from the solubility data. In order to estimate the contribution of enthalpic and entropic terms, standard molar enthalpies ({delta}{sub tr} H {sup 0}) and entropies ({delta}{sub tr} S {sup 0}) of transfer have also been calculated. The decrease in solubility is correlated to the positive {delta}{sub tr} G {sup 0} value which is mainly of enthalpic origin.

  3. Rapid determination of water- and fat-soluble vitamins with microemulsion electrokinetic chromatography.

    Science.gov (United States)

    Yin, Changna; Cao, Yuhua; Ding, Shaodong; Wang, Yun

    2008-06-06

    A rapid, reliable and reproducible method based on microemulsion electrokinetic chromatography (MEEKC) for simultaneous determination of 13 kinds of water- and fat-soluble vitamins has been developed in this work. A novel microemulsion system consisting of 1.2% (w/w) sodium lauryl sulphate (SDS), 21% (v/v) 1-butanol, 18% (v/v) acetonitrile, 0.8% (w/w) n-hexane, 20mM borax buffer (pH 8.7) was applied to improve selectivity and efficiency, as well as shorten analysis time. The composition of microemulsion used as the MEEKC running buffer was investigated thoroughly to obtain stable separation medium, as well as the optimum determination conditions. Acetonitrile as the organic solvent modifier, pH of the running buffer and 1-butanol as the co-surfactant played the most important roles for the separation of the fat-soluble vitamins, water-soluble vitamins and stabilization of system, respectively. The 13 water- and fat-soluble vitamins were baseline separated within 30 min. The system was applied to determine water- and fat-soluble vitamins in commercial multivitamin pharmaceutical formulation, good accuracy and precision were obtained with recoveries between 97% and 105%, relative standard derivations (RSDs) less than 1.8% except vitamin C, and acceptable quantitative results corresponding to label claim.

  4. Temperature and salt addition effects on the solubility behaviour of some phenolic compounds in water

    International Nuclear Information System (INIS)

    Noubigh, Adel; Abderrabba, Manef; Provost, Elise

    2007-01-01

    Solubility-temperature dependence data for six phenolic compounds (PhC), contained in olive mill wastewater (OMWW), in water and in some chloride salts (KCl, NaCl, and LiCl) aqueous solutions have been presented and solution standard molar enthalpies (Δ sol H 0 ) were determined using Van't Hoff plots. The temperature was varied from 293.15 K to 318.15 K. Solubility data were estimated using a thermostated reactor and HPLC analysis. It has been observed that solubility, in pure water and in aqueous chloride solutions, increases with increasing temperature. The salting-out LiCl > NaCl > KCl order obtained at 298.15 K is confirmed. Results were interpreted in terms of the salt hydration shells and the ability of the solute to form hydrogen-bond with water. The standard molar Gibbs free energies of transfer of PhC (Δ tr G 0 ) from pure water to aqueous solutions of the chloride salts have been calculated from the solubility data. In order to estimate the contribution of enthalpic and entropic terms, standard molar enthalpies (Δ tr H 0 ) and entropies (Δ tr S 0 ) of transfer have also been calculated. The decrease in solubility is correlated to the positive Δ tr G 0 value which is mainly of enthalpic origin

  5. Separation of three water-soluble vitamins by poly(dimethylsiloxane) microchannel electrophoresis with electrochemical detection.

    Science.gov (United States)

    Li, Xiang-Yun; Zhang, Qian-Li; Lian, Hong-Zhen; Xu, Jing-Juan; Chen, Hong-Yuan

    2007-09-01

    A method for rapid separation and sensitive determination of three water-soluble vitamins, pyridoxine, ascorbic acid (VC), and p-aminobenzoic acid (PABA) has been developed by PDMS microchannel electrophoresis integrated with amperometric detection. After treatment of the microchip with oxygen plasma, the peak shapes of the three analytes were essentially improved. Pyridoxine, VC, and PABA were well separated within only 80 s in a running buffer of 20 mM borate solution (pH 8.5). Good linearity was obtained within the concentration range of 2-200 microM for the three water-soluble vitamins. The detection limits were 1.0 microM for pyridoxine and VC, and 1.5 microM for PABA. The proposed method has been successfully applied to real human urine sample, without solid phase extraction, with recoveries of 80-122% for the three water-soluble vitamins.

  6. Effect of supplementation of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives.

    Science.gov (United States)

    Talikoti, Prashanth; Bobby, Zachariah; Hamide, Abdoul

    2015-01-01

    The objective of the study was to evaluate the effect of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives. Sixty prehypertensives were recruited and randomized into 2 groups of 30 each. One group received water-soluble vitamins and the other placebo for 4 months. Further increase in blood pressure was not observed in the vitamin group which increased significantly in the placebo group at the end of 4 months. Malonedialdehyde and protein carbonylation were reduced during the course of treatment with vitamins whereas in the placebo group there was an increase in the level of malondialdehyde. In conclusion, supplementation of water-soluble vitamins in prehypertension reduces oxidative stress and its progression to hypertension.

  7. Studies on dissolution enhancement and mathematical modeling of drug release of a poorly water-soluble drug using water-soluble carriers.

    Science.gov (United States)

    Ahuja, Naveen; Katare, Om Prakash; Singh, Bhupinder

    2007-01-01

    Role of various water-soluble carriers was studied for dissolution enhancement of a poorly soluble model drug, rofecoxib, using solid dispersion approach. Diverse carriers viz. polyethylene glycols (PEG 4000 and 6000), polyglycolized fatty acid ester (Gelucire 44/14), polyvinylpyrollidone K25 (PVP), poloxamers (Lutrol F127 and F68), polyols (mannitol, sorbitol), organic acid (citric acid) and hydrotropes (urea, nicotinamide) were investigated for the purpose. Phase-solubility studies revealed AL type of curves for each carrier, indicating linear increase in drug solubility with carrier concentration. The sign and magnitude of the thermodynamic parameter, Gibbs free energy of transfer, indicated spontaneity of solubilization process. All the solid dispersions showed dissolution improvement vis-à-vis pure drug to varying degrees, with citric acid, PVP and poloxamers as the most promising carriers. Mathematical modeling of in vitro dissolution data indicated the best fitting with Korsemeyer-Peppas model and the drug release kinetics primarily as Fickian diffusion. Solid state characterization of the drug-poloxamer binary system using XRD, FTIR, DSC and SEM techniques revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement in dissolution rate.

  8. Urinary excretion levels of water-soluble vitamins in pregnant and lactating women in Japan.

    Science.gov (United States)

    Shibata, Katsumi; Fukuwatari, Tsutomu; Sasaki, Satoshi; Sano, Mitsue; Suzuki, Kahoru; Hiratsuka, Chiaki; Aoki, Asami; Nagai, Chiharu

    2013-01-01

    Recent studies have shown that the urinary excretion levels of water-soluble vitamins can be used as biomarkers for the nutritional status of these vitamins. To determine changes in the urinary excretion levels of water-soluble vitamins during pregnant and lactating stages, we surveyed and compared levels of nine water-soluble vitamins in control (non-pregnant and non-lactating women), pregnant and lactating women. Control women (n=37), women in the 2nd (16-27 wk, n=24) and 3rd trimester of pregnancy (over 28 wk, n=32), and early- (0-5 mo, n=54) and late-stage lactating (6-11 mo, n=49) women took part in the survey. The mean age of subjects was ~30 y, and mean height was ~160 cm. A single 24-h urine sample was collected 1 d after the completion of a validated, self-administered comprehensive diet history questionnaire to measure water-soluble vitamins or metabolites. The average intake of each water-soluble vitamin was ≍ the estimated average requirement value and adequate intake for the Japanese Dietary Reference Intakes in all life stages, except for vitamin B6 and folate intakes during pregnancy. No change was observed in the urinary excretion levels of vitamin B2, vitamin B6, vitamin B12, biotin or vitamin C among stages. Urine nicotinamide and folate levels were higher in pregnant women than in control women. Urine excretion level of vitamin B1 decreased during lactation and that of pantothenic acid decreased during pregnancy and lactation. These results provide valuable information for setting the Dietary Reference Intakes of water-soluble vitamins for pregnant and lactating women.

  9. Gastrointestinal absorption of soluble uranium from drinking water by man

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Singh, N.P.; Ruth, H.; Rallison, M.L.; Burleigh, D.P.

    1989-01-01

    The gastrointestinal absorption of uranium has been measured in ten normal healthy adult volunteers of both sexes by feeding them one litre of water containing 200 to 300 μg of uranium per litre. The water was consumed during normal daytime activities while food was also ingested at its normal rate. Complete collections of urine and faeces were made and compounded on a daily basis over a period of two weeks, one week being prior to the consumption of the uranium-containing water. Uranium was measured by radiochemical separation followed by alpha spectrometry. Both 234 U and 238 U were determined. The results on these people showed that the uptake of uranium under these conditions averaged 0.6%, well below the f 1 of 5% assumed by the ICRP. (author)

  10. Amino acid digestibility of corn distillers dried grains with solubles, liquid condensed solubles, pulse dried thin stillage, and syrup balls fed to growing pigs.

    Science.gov (United States)

    Soares, J A; Stein, H H; Singh, V; Shurson, G S; Pettigrew, J E

    2012-04-01

    Distillers dried grains with solubles (DDGS) has low and variable AA digestibility. The variability is often attributed to damage during the heating process, and it has been suggested that the damage happens to the soluble components of DDGS such as reducing sugars. Combining solubles and grains sometimes produces syrup balls (SB); their digestibility is unknown. The objective of this experiment was to identify potential sources of poor and variable AA digestibility in DDGS. Specifically, our objective was to determine whether the problems are associated with the solubles component or with SB. The ingredients evaluated were DDGS, intact SB, ground SB, liquid condensed solubles (LCS), and pulse dried thin stillage (PDTS) obtained from the same ethanol plant. The LCS is produced by evaporation of thin stillage. Each ingredient was used as the only source of AA in an experimental diet. In a duplicate 6 × 6 Latin square design with 7-d adaptation and collection periods, the 6 treatments consisted of an N-free diet and the 5 test ingredients. Pigs had 5 d of adaptation to each diet, and on d 6 and 7 ileal digesta were collected from an ileal cannula for 8 h each day. Both SB treatments had apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA that were similar or greater (P < 0.05) than those of DDGS. The AID and SID values of Lys and a few other AA were similar in LCS (SID Lys: 63.1%) and DDGS (SID Lys: 61.5%), but the digestibility values of most AA in LCS were less than in DDGS (P < 0.05). The low digestibility of AA in LCS was most pronounced for Met (SID: LCS, 41.9% vs. DDGS, 82.8%). The LCS had less (P < 0.05) AID and SID of CP (SID: 67.8%) than intact SB (SID: 85.2%) and ground SB (SID: 85.9%) as well as all AA. The PDTS generally had the least AID and SID and had less (P < 0.05) CP (SID: 55.3%) and several AA, including Lys, compared with LCS. In conclusion, the presence of SB does not decrease AA digestibility of DDGS, and the LCS

  11. Relationship Between Urinary Concentrations of Nine Water-soluble Vitamins and their Vitamin Intakes in Japanese Adult Males

    OpenAIRE

    Shibata, Katsumi; Hirose, Junko; Fukuwatari, Tsutomu

    2014-01-01

    Excess water-soluble vitamins are thought to be eliminated in the urine. We have reported a strong relationship between water-soluble vitamin intake and urinary excretion in females. The relationship, however, is not well understood in males. In the present experiment, 10 Japanese male subjects were given a standard Japanese diet for the first week. The subjects remained on the same diet, and a synthesized water-soluble vitamin mixture containing one time the Dietary Reference Intakes (DRIs) ...

  12. Preparation and tribology properties of water-soluble fullerene derivative nanoball

    Directory of Open Access Journals (Sweden)

    Guichang Jiang

    2017-02-01

    Full Text Available Water-soluble fullerene derivatives were synthesized via radical polymerization. They are completely soluble in water, yielding a clear brown solution. The products were characterized by FTIR, UV–Vis, 1H-NMR, 13CNMR, GPC, TGA, and SEM. Four-ball tests show that the addition of a certain concentration of the fullerene derivatives to base stock (2 wt.% triethanolamine aqueous solution can effectively increase both the load-carrying capacity (PB value, and the resistance to wear. SEM observations confirm the additive results in a reduced diameter of the wear scar and decreased wear.

  13. Smart polyelectrolyte microcapsules as carriers for water-soluble small molecular drug.

    Science.gov (United States)

    Song, Weixing; He, Qiang; Möhwald, Helmuth; Yang, Yang; Li, Junbai

    2009-10-15

    Heat treatment is introduced as a simple method for the encapsulation of low molecular weight water-soluble drugs within layer-by-layer assembled microcapsules. A water-soluble drug, procainamide hydrochloride, could thus be encapsulated in large amount and enriched by more than 2 orders of magnitude in the assembled PDADMAC/PSS capsules. The shrunk capsules could control the unloading rate of drugs, and the drugs could be easily unloaded using ultrasonic treatment. The encapsulated amount could be quantitatively controlled via the drug concentration in the bulk. We also found that smaller capsules possess higher encapsulation capability.

  14. Lipid-based formulations for oral administration of poorly water-soluble drugs

    DEFF Research Database (Denmark)

    Mu, Huiling; Holm, René; Müllertz, Anette

    2013-01-01

    Lipid-based drug delivery systems have shown great potentials in oral delivery of poorly water-soluble drugs, primarily for lipophilic drugs, with several successfully marketed products. Pre-dissolving drugs in lipids, surfactants, or mixtures of lipids and surfactants omits the dissolving....../dissolution step, which is a potential rate limiting factor for oral absorption of poorly water-soluble drugs. Lipids not only vary in structures and physiochemical properties, but also in their digestibility and absorption pathway; therefore selection of lipid excipients and dosage form has a pronounced effect...

  15. Bioavailability assessment of the lipophilic benfotiamine as compared to a water-soluble thiamin derivative.

    Science.gov (United States)

    Bitsch, R; Wolf, M; Möller, J; Heuzeroth, L; Grüneklee, D

    1991-01-01

    The bioequivalence of thiamin in 2 therapeutically used preparations was tested in 10 healthy young men. Thiamin was orally administered either as lipophilic benfotiamine or as water-soluble thiamin mononitrate. Biokinetic data, measured as area under the curve and maximal concentration in plasma and hemolysate after ingestion, demonstrated a significantly improved bioavailability from the lipophilic derivative despite an ingested dose of only 40% as compared with the water-soluble salt. A superior cellular efficacy of benfotiamine was also concluded from the short-term stimulation of the thiamin-dependent transketolase activity in erythrocytes.

  16. Studeis on the immobilization of water soluble phosphatic fertilizer in some soils with 32P

    International Nuclear Information System (INIS)

    Zhang Yumei; Li Rensheng; Xu Xinyu

    1985-01-01

    Using superphosphate lablled with 32 P, we studied immobilization of water-soluble phosphatic fertilizer on 12 typies of soil. The experimental result showed that major factors to govern immobilization of water-soluble phosphatic fertilizer are: quickly availible Fe that showed positive correlation with the immobilization when it was 4.64-65.72 ppm; and pH that showed negative correlation with the immobilization when it was between 5.35 and 8.88. CaCO 3 and organic matter showed a great effect on the immobilization though there wasn't obvious correlation among them

  17. Synthesis of gold nanoclusters: a fluorescent marker for water-soluble TiO2 nanotubes

    International Nuclear Information System (INIS)

    Ratanatawanate, Chalita; Yu Jing; Zhou Chen; Zheng Jie; Balkus, Kenneth J Jr

    2011-01-01

    The first example of a water-soluble wrapped titania nanotube (TNT) decorated with fluorescent gold nanoparticles has been prepared. Gold nanoparticles ∼ 1.6 nm in diameter were grown on the TiO 2 nanotubes using a thiolactic acid linker to control the size. The gold clusters emit at 660 nm in water and were imaged using confocal microscopy. The gold decorated TNTs were suspended in water by wrapping the nanotubes with poly-L-arginine.

  18. A water soluble heteropolyoxotungstate as a selective, efficient and ...

    Indian Academy of Sciences (India)

    Administrator

    In the catalytic system described here product isolation is easy, and the aqueous catalyst solution can be re-used several times with little loss in ... tle loss in the total amount of the heavy metal, which makes the overall process green ..... Chem. Res. 27 387. 12. Waters T, O'Hair R A J and Wedd A G 2003 J. Am. Chem. Soc.

  19. Streamers in water and other dielectric liquids

    International Nuclear Information System (INIS)

    Kolb, J F; Joshi, R P; Xiao, S; Schoenbach, K H

    2008-01-01

    Experimental results on the inception and propagation of streamers in water generated under the application of high electric fields are reviewed. Characteristic parameters, such as breakdown voltage, polarity of the applied voltage, propagation velocities and other phenomenological features, are compared with similar phenomena in other dielectric liquids and in gases. Consequently, parameters that are expected to influence the development of streamers in water are discussed with respect to the analogous well-established models and theories for the related mechanisms in gases. Most of the data support the notion that an initial low-density nucleation site or gas-filled bubble assists the initiation of a streamer. Details of this theory are laid out explaining the observed differences in the breakdown originating from the anode versus the cathode locations. The mechanisms can also be applied to streamer propagation, although some observations cannot be satisfactorily explained.

  20. Polarized View of Supercooled Liquid Water Clouds

    Science.gov (United States)

    Alexandrov, Mikhail D.; Cairns, Brian; Van Diedenhoven, Bastiaan; Ackerman, Andrew S.; Wasilewski, Andrzej P.; McGill, Matthew J.; Yorks, John E.; Hlavka, Dennis L.; Platnick, Steven E.; Arnold, G. Thomas

    2016-01-01

    Supercooled liquid water (SLW) clouds, where liquid droplets exist at temperatures below 0 C present a well known aviation hazard through aircraft icing, in which SLW accretes on the airframe. SLW clouds are common over the Southern Ocean, and climate-induced changes in their occurrence is thought to constitute a strong cloud feedback on global climate. The two recent NASA field campaigns POlarimeter Definition EXperiment (PODEX, based in Palmdale, California, January-February 2013) and Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS, based in Houston, Texas in August- September 2013) provided a unique opportunity to observe SLW clouds from the high-altitude airborne platform of NASA's ER-2 aircraft. We present an analysis of measurements made by the Research Scanning Polarimeter (RSP) during these experiments accompanied by correlative retrievals from other sensors. The RSP measures both polarized and total reflectance in 9 spectral channels with wavelengths ranging from 410 to 2250 nm. It is a scanning sensor taking samples at 0.8deg intervals within 60deg from nadir in both forward and backward directions. This unique angular resolution allows for characterization of liquid water droplet size using the rainbow structure observed in the polarized reflectances in the scattering angle range between 135deg and 165deg. Simple parametric fitting algorithms applied to the polarized reflectance provide retrievals of the droplet effective radius and variance assuming a prescribed size distribution shape (gamma distribution). In addition to this, we use a non-parametric method, Rainbow Fourier Transform (RFT),which allows retrieval of the droplet size distribution without assuming a size distribution shape. We present an overview of the RSP campaign datasets available from the NASA GISS website, as well as two detailed examples of the retrievals. In these case studies we focus on cloud fields with spatial features

  1. Prediction of the solubility of selected pharmaceuticals in water and alcohols with a group contribution method

    International Nuclear Information System (INIS)

    Pelczarska, Aleksandra; Ramjugernath, Deresh; Rarey, Jurgen; Domańska, Urszula

    2013-01-01

    Highlights: ► The prediction of solubility of pharmaceuticals in water and alcohols was presented. ► Improved group contribution method UNIFAC was proposed for 42 binary mixtures. ► Infinite activity coefficients were used in a model. ► A semi-predictive model with one experimental point was proposed. ► This model qualitatively describes the temperature dependency of Pharms. -- Abstract: An improved group contribution approach using activity coefficients at infinite dilution, which has been proposed by our group, was used for the prediction of the solubility of selected pharmaceuticals in water and alcohols [B. Moller, Activity of complex multifunctional organic compounds in common solvents, PhD Thesis, Chemical Engineering, University of KwaZulu-Natal, 2009]. The solubility of 16 different pharmaceuticals in water, ethanol and octan-1-ol was predicted over a fairly wide range of temperature with this group contribution model. The predicted values, along with values computed with the Schroeder-van Laar equation, are compared to experimental results published by us previously for 42 binary mixtures. The predicted solubility values were lower than those from the experiments for most of the mixtures. In order to improve the prediction method, a semi-predictive calculation using one experimental solubility value was implemented. This one point prediction has given acceptable results when comparison is made to experimental values

  2. The Chameleonic Behavior of Ionic Liquids and its Impact on the Solubility Parameters Estimation

    DEFF Research Database (Denmark)

    Batista, Marta; Neves, Catarina S; Carvalho, Pedro Jorge

    2011-01-01

    The possibility to develop a solubility parameter scale, with the purpose of predicting the performance and help the selection of ILs, is here evaluated. For the estimation of solubility parameters infinite dilution activity coefficient data is used. The results allowed the identification of a cu...

  3. Improvement of humidity resistance of water soluble core by precipitation method

    Directory of Open Access Journals (Sweden)

    Zhang Long

    2011-05-01

    Full Text Available Water soluble core has been widely used in manufacturing complex metal components with hollow configurations or internal channels; however, the soluble core can absorb water easily from the air at room temperature. To improve the humidity resistance of the water soluble core and optimize the process parameters applied in manufacturing of the water soluble core, a precipitation method and a two-level-three-full factorial central composite design were used, respectively. The properties of the cores treated by the precipitation method were compared with that without any treatment. Through a systematical study by means of both an environmental scanning electron microscope (ESEM and an energy dispersive X-ray (EDX analyzer, the results indicate that the hygroscopicity can be reduced by 20% and the obtained optimal process conditions for three critical control factors affecting the hygroscopicity are 0.2 g·mL-1 calcium chloride concentration, 4% water concentration and 0 min ignition time. The porous surface coated by calcium chloride and the high humidity resistance products generated in the precipitation reaction between calcium chloride and potassium carbonate may contribute to the lower hygroscopicity.

  4. Formation of water-soluble soybean polysaccharides from spent flakes by hydrogen peroxide treatment

    DEFF Research Database (Denmark)

    Pierce, Brian; Wichmann, Jesper; Tran, Tam H.

    2016-01-01

    70% of the original insoluble material as high molar mass soluble polysaccharides. A design of experiment was used to quantify the effects of pH, reaction time, and hydrogen peroxide concentration on the reaction yield, average molar mass, and free monosaccharides generated. The resulting product......In this paper we propose a novel chemical process for the generation of water-soluble polysaccharides from soy spent flake, a by-product of the soy food industry. This process entails treatment of spent flake with hydrogen peroxide at an elevated temperature, resulting in the release of more than...... is low in protein, fat, and minerals and contains predominantly water-soluble polysaccharides of high molar mass, including arabinan, type I arabinogalactan, homogalacturonan, xyloglucan, rhamnogalacturonan, and (glucurono)arabinoxylan. This treatment provides a straightforward approach for generation...

  5. Solubility of fragrance raw materials in water: Experimental study, correlations, and Mod. UNIFAC (Do) predictions

    Energy Technology Data Exchange (ETDEWEB)

    Domanska, Urszula, E-mail: ula@ch.pw.edu.p [Department of Physical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland); Paduszynski, Kamil; Niszczota, Zaneta K. [Department of Physical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland)

    2011-01-15

    The (liquid + liquid) and (solid + liquid) phase equilibria of nine binary mixtures containing fragrance raw materials (FRM) such as aliphatic ketones and compounds based on cyclohexane with water were investigated. The systems {l_brace}2-heptanone, or 2-nonanone, or 2-undecanone, or 2-tridecanone, or cyclohexyl carboxylic acid (CCA), or cyclohexyl acetic acid (CAA), or 2-cyclohexyl ethanol (2CE) or cyclohexyl acetate (CA), or 2-cyclohexyl ethyl acetate (2CEA) + water (2){r_brace} have been measured by a dynamic method in wide range of temperatures from (290 to 360) K and ambient pressure. For all systems immiscibility in the liquid phase was detected. The experimental data was correlated by means of the NRTL equation, utilizing parameters derived from the (liquid + liquid) equilibrium. Additionally, the binary mixtures were predicted with the Mod. UNIFAC (Do) model, with known from literature parameters, with very good results.

  6. Solubility of fragrance raw materials in water: Experimental study, correlations, and Mod. UNIFAC (Do) predictions

    International Nuclear Information System (INIS)

    Domanska, Urszula; Paduszynski, Kamil; Niszczota, Zaneta K.

    2011-01-01

    The (liquid + liquid) and (solid + liquid) phase equilibria of nine binary mixtures containing fragrance raw materials (FRM) such as aliphatic ketones and compounds based on cyclohexane with water were investigated. The systems {2-heptanone, or 2-nonanone, or 2-undecanone, or 2-tridecanone, or cyclohexyl carboxylic acid (CCA), or cyclohexyl acetic acid (CAA), or 2-cyclohexyl ethanol (2CE) or cyclohexyl acetate (CA), or 2-cyclohexyl ethyl acetate (2CEA) + water (2)} have been measured by a dynamic method in wide range of temperatures from (290 to 360) K and ambient pressure. For all systems immiscibility in the liquid phase was detected. The experimental data was correlated by means of the NRTL equation, utilizing parameters derived from the (liquid + liquid) equilibrium. Additionally, the binary mixtures were predicted with the Mod. UNIFAC (Do) model, with known from literature parameters, with very good results.

  7. Diffusivity, activity and solubility of oxygen in liquid lead and lead-bismuth eutectic alloy by electrochemical methods

    International Nuclear Information System (INIS)

    Ganesan, Rajesh; Gnanasekaran, T.; Srinivasa, Raman S.

    2006-01-01

    The diffusivity of oxygen in liquid lead and lead-bismuth eutectic (LBE) alloy was measured by a potentiostatic method and is given by log(D O Pb /cm 2 s -1 )=-2.554-2384/T(+/-0.070), 818-1061K, and log(D O LBE /cm 2 s -1 )=-0.813-3612/T(+/-0.091), 811-980K. The activity of oxygen in lead and LBE was determined by coulometric titration experiments. Using the measured data, the standard free energy of dissolution of oxygen in liquid lead and LBE was derived and is given byG O(Pb) xs =-121349+16.906T(+/-560)J(gatomO) -1 ,815-1090K,G O(LBE) xs = -127398+27.938T(+/-717)J(gatomO) -1 ,812-1012K.Using the above data, the Gibbs energy of formation of PbO(s) and equilibrium oxygen pressures measured over the oxygen-saturated LBE alloy, the solubility of oxygen in liquid lead and LBE were derived. The solubility of oxygen in liquid lead and LBE are given by log(S/at.%O)=-5100/T+4.32 (+/-0.04), 815-1090K and log(S/at.%O)=-4287/T+3.53 (+/-0.06), 812-1012K respectively.

  8. Highly Water-Soluble Magnetic Nanoparticles as Novel Draw Solutes in Forward Osmosis for Water Reuse

    KAUST Repository

    Ling, Ming Ming

    2010-06-16

    Highly hydrophilic magnetic nanoparticles have been molecularly designed. For the first time, the application of highly water-soluble magnetic nanoparticles as novel draw solutes in forward osmosis (FO) was systematically investigated. Magnetic nanoparticles functionalized by various groups were synthesized to explore the correlation between the surface chemistry of magnetic nanoparticles and the achieved osmolality. We verified that magnetic nanoparticles capped with polyacrylic acid can yield the highest driving force and subsequently highest water flux among others. The used magnetic nanoparticles can be captured by the magnetic field and recycled back into the stream as draw solutes in the FO process. In addition, magnetic nanoparticles of different diameters were also synthesized to study the effect of particles size on FO performance. We demonstrate that the engineering of surface hydrophilicity and magnetic nanoparticle size is crucial in the application of nanoparticles as draw solutes in FO. It is believed that magnetic nanoparticles will soon be extensively used in this area. © 2010 American Chemical Society.

  9. Monoglyceride-based self-assembling copolymers as carriers for poorly water-soluble drugs.

    Science.gov (United States)

    Rouxhet, L; Dinguizli, M; Latere Dwan'isa, J P; Ould-Ouali, L; Twaddle, P; Nathan, A; Brewster, M E; Rosenblatt, J; Ariën, A; Préat, V

    2009-12-01

    To develop self-assembling polymers forming polymeric micelles and increasing the solubility of poorly soluble drugs, amphiphilic polymers containing a hydrophilic PEG moiety and a hydrophobic moiety derived from monoglycerides and polyethers were designed. The biodegradable copolymers were obtained via a polycondensation reaction of polyethylene glycol (PEG), monooleylglyceride (MOG) and succinic anhydride (SA). Polymers with molecular weight below 10,000 g/mol containing a minimum of 40 mol% PEG and a maximum of 10 mol% MOG self-assembled spontaneously in aqueous media upon gentle mixing. They formed particles with a diameter of 10 nm although some aggregation was evident. The critical micellar concentration varied between 3x10(-4) and 4x10(-3) g/ml, depending on the polymer. The cloud point (> or = 66 degrees C) and flocculation point (> or = 0.89 M) increased with the PEG chain length. At a 1% concentration, the polymers increased the solubility of poorly water-soluble drug candidates up to 500-fold. Drug solubility increased as a function of the polymer concentration. HPMC capsules filled with these polymers disintegrated and released model drugs rapidly. Polymer with long PEG chains had a lower cytotoxicity (MTT test) on Caco-2 cells. All of these data suggest that the object polymers, in particular PEG1000/MOG/SA (45/5/50) might be potential candidates for improving the oral biopharmaceutical performance of poorly soluble drugs.

  10. Water sorption and solubility of bulk-fill composites polymerized with a third generation LED LCU

    Directory of Open Access Journals (Sweden)

    Tuğba MİSİLLİ

    2017-10-01

    Full Text Available Abstract The aim of this study was to compare the degree of water sorption and solubility in bulk-fills after curing with a polywave light source. A total of 120 disc-shaped specimens (8 mm diameter; 4 mm depth were prepared from three regular bulk-fill materials (X-tra Fil, Tetric N-Ceram Bulk Fill, SonicFill, and a control material (Filtek Z250, cured in 3 different modes (standard: 1000 mW/cm2-20 s; high power: 1400 mW/cm2-12 s; xtra power: 3200 mW/cm2-6 s using a third generation light-emitting diode light curing unit. Water sorption and solubility levels of the specimens were measured according to the ISO 4049:2009 specification after storing in distilled water for 30 days. Data were analyzed using two-way ANOVA and Tukey’s post-hoc test (p < 0.05. The Z250 sample exposed to high power presented a higher sorption compared to the X-tra Fil and SonicFill samples. In xtra power mode, the values of Z250 and SonicFill were similar to each other and higher compared to those of X-tra Fil. Only SonicFill exhibited significantly different sorption values depending on the curing mode, the highest of which was achieved when using the xtra power mode. The highest solubility values were obtained for SonicFill. No statistically significant differences were found among other groups. No significant correlation was detected between water sorption and solubility. The traditional composite group exhibited a higher water sorption values than the bulk-fills. The reduction in polymerization time significantly increased the sorption of SonicFill. SonicFill showed the highest water solubility value among the composites tested.

  11. The effects of fire temperatures on water soluble heavy metals.

    Science.gov (United States)

    Pereira, P.; Ubeda, X.; Martin, D. A.

    2009-04-01

    Fire ash are majority composed by base cations, however the mineralized organic matter, led also available to transport a higher quantity of heavy metals that potentially could increase a toxicity in soil and water resources. The amount availability of these elements depend on the environment were the fire took place, burning temperature and combusted tree specie. The soil and water contamination from fire ash has been neglected, because the majority of studies are focused on base cations dynamic. Our research, beside contemplate major elements, is focused in to study the behavior of heavy metals released from ash slurries created at several temperatures under laboratory environment, prescribed fires and wildland fires. The results presented in these communication are preliminary and study the presence of Aluminium (Al3+), Manganese (Mn2+), Iron (Fe2+) and Zinc (Zn2+) of ash slurries generated in laboratory environment at several temperatures (150°, 200°, 250°, 300°, 350°, 400°,450°, 500°, 550°C) from Quercus suber, Quercus robur, Pinus pinea and Pinus pinaster and from a low medium temperature prescribed fire in a forest dominated Quercus suber trees. We observed that ash produced at lower and medium temperatures (Pinus ashes. Fe2+ and Zn2+ showed a reduced concentration in test solution in relation to unburned sample at all temperatures of exposition. In the results obtained from prescribed fire, we identify a higher release of Al3+ and a decrease of the remain elements. The solubilization of these elements are related with pH levels and ash calcite content, because their ability to capture ions in solution. Moreover, the amount and the type of ions released in relation to unburned sample vary in each specie. In this study Al3+ release is related with Quercus species and Mn2+ with Pinus species. Fire ashes can be an environmental problem, because at long term can increase soil acidity. After all base cations have being leached, pH values decrease, and

  12. Solubility of fused silica in sub- and supercritical water: Estimation from a thermodynamic model

    Czech Academy of Sciences Publication Activity Database

    Karásek, Pavel; Šťavíková, Lenka; Planeta, Josef; Hohnová, Barbora; Roth, Michal

    2013-01-01

    Roč. 83, NOV (2013), s. 72-77 ISSN 0896-8446 R&D Projects: GA ČR(CZ) GAP106/12/0522 Institutional support: RVO:68081715 Keywords : amorphous silica * fused silica * supercritical water * aqueous solubility Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.571, year: 2013

  13. Synthesis of phthalocyanines-ALA conjugates: water-soluble compounds with low aggregation.

    Science.gov (United States)

    de Oliveira, Kleber T; de Assis, Francisco F; Ribeiro, Anderson O; Neri, Claudio R; Fernandes, Adjaci U; Baptista, Mauricio S; Lopes, Norberto P; Serra, Osvaldo A; Iamamoto, Yassuko

    2009-10-16

    Syntheses of two water-soluble phthalocyanines (Pc) containing 5-aminolevulinic acid (ALA) linked to the core structure are described. These compounds were prepared by using original functionalizations, and they present remarkable structural and photophysical features, indicating that they could be applied to photodynamic therapy (PDT).

  14. Profiling and relationship of water-soluble sugar and protein compositions in soybean seeds.

    Science.gov (United States)

    Yu, Xiaomin; Yuan, Fengjie; Fu, Xujun; Zhu, Danhua

    2016-04-01

    Sugar and protein are important quality traits in soybean seeds for making soy-based food products. However, the investigations on both compositions and their relationship have rarely been reported. In this study, a total of 35 soybean germplasms collected from Zhejiang province of China, were evaluated for both water-soluble sugar and protein. The total water-soluble sugar (TWSS) content of the germplasms studied ranged from 84.70 to 140.91 mg/g and the water-soluble protein (WSP) content varied from 26.5% to 36.0%. The WSP content showed positive correlations with the TWSS and sucrose contents but negative correlations with the fructose and glucose contents. The clustering showed the 35 germplasms could be divided into four groups with specific contents of sugar and protein. The combination of water-soluble sugar and protein profiles provides useful information for future breeding and genetic research. This investigation will facilitate future work for seed quality improvement. Copyright © 2015. Published by Elsevier Ltd.

  15. pKa Determination of water-soluble calix[4]arenes

    NARCIS (Netherlands)

    Shinkai, Seiji; Araki, Koji; Grootenhuis, P.D.J.; Reinhoudt, David

    1991-01-01

    Neutral, water-soluble 5,11,17,23-tetrakis[bis-(2-hydroxyethyl)aminosulphonyl]calix[4]arene-25,26,27,28-tetraol and 5,11,17,23-tetranitrocalix[4]arene-25,26,27,28-tetraol have been synthesized and the pKa values of the OH groups determined in an aqueous system.

  16. 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

  17. Fluorescent Water Soluble Polymers for Isozyme-Selective Interactions with Matrix Metalloproteinase-9

    Science.gov (United States)

    Dutta, Rinku; Scott, Michael D.; Haldar, Manas K.; Ganguly, Bratati; Srivastava, D. K.; Friesner, Daniel L.; Mallik, Sanku

    2011-01-01

    Matrix metalloproteinases (MMPs) are overexpressed in various pathological conditions, including various cancers. Although these isozymes have similar active sites, the patterns of exposed amino acids on their surfaces are different. Herein, we report the synthesis and molecular interactions of two water-soluble, fluorescent polymers which demonstrate selective interactions with MMP-9 compared to MMP-7 and -10. PMID:21367603

  18. Testing water-soluble carbohydrate QTL effects in perennial ryegrass (Lolium perenne L.) by marker selection

    NARCIS (Netherlands)

    Turner, L.B.; Farrell, M.; Humphreys, M.O.; Dolstra, O.

    2010-01-01

    Water-soluble carbohydrates (WSC) are an important factor determining the nutritional value of grass forage and development of genetic markers for selection of WSC traits in perennial ryegrass would benefit future breeding programmes. Quantitative trait loci (QTLs) for WSC have been published for an

  19. Antioxidative activity of water soluble polysaccharide in pumpkin fruits (Cucurbita maxima Duchesne).

    Science.gov (United States)

    Nara, Kazuhiro; Yamaguchi, Akira; Maeda, Naomi; Koga, Hidenori

    2009-06-01

    We evaluated the antioxidative activity of a water soluble polysaccharide fraction (WSP) from pumpkin fruits (Cucurbita maxima Duchesne). In the WSP, DPPH radical scavenging and superoxide dismutase-like activity increased depending on the total sugar content. Furthermore, the WSP can serve as an inhibitor of ascorbic acid oxidation. The efficacy was also affected by the total sugar content.

  20. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  1. In vitro degradation of dermal sheep collagen cross-linked using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    Bacterial collagenase was used to study the susceptibility of dermal sheep collagen (DSC) cross-inked with a mixture of the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide (EIN-DSC) towards enzymatic degradation. Contrary to

  2. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Olde damink, L.H.H.; Olde Damink, L.H.H.; Dijkstra, Pieter J.; van Luyn, M.J.A.; van Wachem, P.B.; Nieuwenhuis, P.; Feijen, Jan

    1996-01-01

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  3. 40 CFR 799.6786 - TSCA water solubility: Generator column method.

    Science.gov (United States)

    2010-07-01

    ... b, using a linear regression equation of C vs. R in the following form: Equation 4: ER15DE00.062... address in paragraph (e) of this section. (b) Introduction—(1) Purpose. (i) The water solubility of a... peak area to volume injected and, from the regression equation of the calibration line, determine the...

  4. Synthesis of water-soluble scaffolds for peptide cyclization, labeling, and ligation

    NARCIS (Netherlands)

    Smeenk, L.E.J.; Dailly, N.; Hiemstra, H.; van Maarseveen, J.H.; Timmerman, P.

    2012-01-01

    The synthesis and applications of water-soluble scaffolds that conformationally constrain side chain unprotected linear peptides containing two cysteines are described. These scaffolds contain a functionality with orthogonal reactivity to be used for labeling and ligation. This is illustrated by the

  5. Distribution of various water soluble radioactive metalloporphyrins in tumor bearing mice

    International Nuclear Information System (INIS)

    Hambright, P.; Fawwaz, R.; Valk, P.; McRae, J.; Bearden, A.J.

    1975-01-01

    The distribution of a variety of water soluble 109 Pd and 64 Cu porphyrins were studied in mice bearing three types of tumors. While the metalloporphyrins are found to have an affinity for neoplastic tissue, substantial extra-tumor concentrations are also noted. Although this limits their value as specific tumor imaging agents, their use in localized therapy is discussed

  6. Temperature and sodium chloride effects on the solubility of anthracene in water

    International Nuclear Information System (INIS)

    Arias-Gonzalez, Israel; Reza, Joel; Trejo, Arturo

    2010-01-01

    The solubility of anthracene was measured in pure water and in sodium chloride aqueous solution (salt concentration, m/mol . kg -1 = 0.1006, 0.5056, and 0.6082) at temperatures between (278 and 333) K. Solubility of anthracene in pure water agrees fairly well with values reported in earlier similar studies. Solubility of anthracene in sodium chloride aqueous solutions ranged from (6 . 10 -8 to 143 . 10 -8 ) mol . kg -1 . Sodium chloride had a salting-out effect on the solubility of anthracene. The salting-out coefficients did not vary significantly with temperature over the range studied. The average salting-out coefficient for anthracene was 0.256 kg . mol -1 . The standard molar Gibbs free energies, Δ tr G o , enthalpies, Δ tr H o , and entropies, Δ tr S o , for the transfer of anthracene from pure water to sodium chloride aqueous solutions were also estimated. Most of the estimated Δ tr G o values were positive [(20 to 1230) J . mol -1 ]. The analysis of the thermodynamic parameters shows that the transfer of anthracene from pure water to sodium chloride aqueous solution is thermodynamically unfavorable, and that this unfavorable condition is caused by a decrease in entropy.

  7. Assessment of acute toxicity of water soluble fraction of diesel on ...

    African Journals Online (AJOL)

    Acute toxicity of water soluble fraction (WSF) of diesel fuel was assessed by evaluating its effects on growth of two marine microalgae, Isochrysis and Chaetoceros. Pure cultures of each of the two microalgae were exposed to concentrations of 0% (controls), 5%, 10%, 15% and 20% of diesel WSF (in triplicates) and allowed ...

  8. Amino acids as co-amorphous stabilizers for poorly water soluble drugs--Part 1

    DEFF Research Database (Denmark)

    Löbmann, Korbinian; Grohganz, Holger; Laitinen, Riikka

    2013-01-01

    molecular weight excipients that form specific molecular interactions with the drug resulting in co-amorphous forms. The two poorly water soluble drugs carbamazepine and indomethacin were combined with amino acids from the binding sites of the biological receptors of these drugs. Mixtures of drug...

  9. Mechanisms and Regulation of Intestinal Absorption of Water-soluble Vitamins: Cellular and Molecular Aspects

    DEFF Research Database (Denmark)

    Nexø, Ebba; Said, Hamid M

    2012-01-01

    The water-soluble vitamins represent a group of structurally and functionally unrelated compounds that share the common feature of being essential for normal cellular functions, growth, and development. With the exception of some endogenous production of niacin, human cells cannot synthesize...

  10. The effect of water solubles on Kelvin effects of the Maritime Polluted ...

    African Journals Online (AJOL)

    In this work microphysical properties of Maritime Polluted aerosols wereextracted from Optical Properties of Aerosols and Clouds (OPAC) after varying the concentrations of water soluble at five different levels. The analytical expressions for the changes in the equilibrium relative humidity (RH), effective radii, effective ...

  11. Biphasic and SAPC Hydroformylation Catalyzed by Rh-phosphines Bound to Water-Soluble Polymers

    DEFF Research Database (Denmark)

    Malmstrøm, Torsten; Andersson, Carlaxel; Hjortkjær, Jes

    1999-01-01

    Coupling of the triphenylphosphine moiety to poly-acrylic acid and poly-ethyleneimine respectively afford the macromolecular ligands PAA-PNH and PEI-PNH. Reaction of the ligands with Rh(CO)2(acac) give water-soluble complexes that are active as catalysts in the hydroformylation ofdifferent olefins...

  12. Temperature and sodium chloride effects on the solubility of anthracene in water

    Energy Technology Data Exchange (ETDEWEB)

    Arias-Gonzalez, Israel [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico); Reza, Joel, E-mail: jreza@imp.m [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico); Trejo, Arturo, E-mail: atrejo@imp.m [Instituto Mexicano del Petroleo, Direccion de Investigacion y Posgrado, Programa de Ingenieria Molecular, Area de Investigacion en Termofisica, Eje Central Lazaro Cardenas Norte 152. 07730, Mexico D.F. (Mexico)

    2010-11-15

    The solubility of anthracene was measured in pure water and in sodium chloride aqueous solution (salt concentration, m/mol . kg{sup -1} = 0.1006, 0.5056, and 0.6082) at temperatures between (278 and 333) K. Solubility of anthracene in pure water agrees fairly well with values reported in earlier similar studies. Solubility of anthracene in sodium chloride aqueous solutions ranged from (6 . 10{sup -8} to 143 . 10{sup -8}) mol . kg{sup -1}. Sodium chloride had a salting-out effect on the solubility of anthracene. The salting-out coefficients did not vary significantly with temperature over the range studied. The average salting-out coefficient for anthracene was 0.256 kg . mol{sup -1}. The standard molar Gibbs free energies, {Delta}{sub tr}G{sup o}, enthalpies, {Delta}{sub tr}H{sup o}, and entropies, {Delta}{sub tr}S{sup o}, for the transfer of anthracene from pure water to sodium chloride aqueous solutions were also estimated. Most of the estimated {Delta}{sub tr}G{sup o} values were positive [(20 to 1230) J . mol{sup -1}]. The analysis of the thermodynamic parameters shows that the transfer of anthracene from pure water to sodium chloride aqueous solution is thermodynamically unfavorable, and that this unfavorable condition is caused by a decrease in entropy.

  13. Synthesis and Characterization of Water-soluble Conjugates of Cabazitaxel Hemiesters-Dextran.

    Science.gov (United States)

    Parhizkar, Elahehnaz; Ahmadi, Fatemeh; Daneshamouz, Saeid; Mohammadi-Samani, Soliman; Sakhteman, Amirhossein; Parhizkar, Golnaz

    2017-11-24

    Cabazitaxel (CTX) is a second- generation taxane derivative, a class of potent anticancer drugs with very low water solubility. CTX is used in patients with resistant prostate cancer unresponsive to the first generation taxane, docetaxel. Currently marketed formulations of CTX contain high concentrations of surfactant and ethanol, which cause severe hypersensitivity reactions in patients. In order to increase its solubility, two hemiester analogs; CTX-succinate and CTX-glutarate were synthesized and characterized. To improve the solubility of hemiesters even more, dextran as a biocompatible polymer was also conjugated to hemiester analogs. MTT assay was performed on MCF-7 cell line to evaluate the cytotoxicity effect of hemiesters and conjugates. Based on the results, hemiester analogs increased water solubility of the drug up to about 3 and 8 fold. Conjugation to dextran enhanced the CTX solubility to more than 1500 fold. These conjugates released the conjugated CTX in less than 24 hours in a pH dependent manner and showed proper hemocompatibility characteristics. The hemiesters had approximately similar cytotoxicity in comparison with CTX and the dextran conjugates showed higher cytotoxicity effect on MCF-7 cell line. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Antimicrobial and Antifungal Effects of Acid and Water-Soluble Chitosan Extracted from Indian Shrimp (Fenneropenaeus indicus Shell

    Directory of Open Access Journals (Sweden)

    Ali Taheri

    2013-06-01

    Full Text Available Background & Objective : Currently, efforts are underway to seek new and effective antimicrobial agents, and marine resources are potent candidates for this aim. The following study was conducted to investigate the efficacy of water-soluble and acid-soluble chitosan against some pathogenic organisms.   Materials & Method s: Inhibition zone of different concentrations (5, 7.5, and 10 mg/ml of acid- soluble and water-soluble chitosan were examined for in vitro antibacterial activity against 4 kinds of hospital bacteria and penicillium sp. Results were compared with 4 standard antibiotics: streptomycin, gentamicin, tetracycline, and erythromycin. Furthermore, minimum inhibitory concentration and minimum lethal concentration were determined.   Results: Inhibition activity of acid-soluble chitosan (10% showed the best result (p value < 0.05, whereas water-soluble chitosan exhibited the least antibacterial effects (p value < 0.05. Chitosan demonstrated maximum effect on V. cholera cerotype ogava , and the least effect was seen on E. coli (p value < 0.05. Acid-soluble chitosan had a more potent effect than the standard antibiotics. Also, acid-soluble chitosan (10% and water-soluble chitosan showed maximum inhibitory effects on penicillium sp.   Conclusion: Chitosan showed maximum antibacterial effect against S. aureus, V. cholerae cerotype ogava, and water-soluble chitosan demonstrated good antifungal effects, revealing a statistically significant difference with common antibacterial and antifungal medicines.

  15. Renal excretion of water-soluble contrast media after enema in the neonatal period.

    Science.gov (United States)

    Kim, Hee Sun; Je, Bo-Kyung; Cha, Sang Hoon; Choi, Byung Min; Lee, Ki Yeol; Lee, Seung Hwa

    2014-08-01

    When abdominal distention occurs or bowel obstruction is suspected in the neonatal period, a water-soluble contrast enema is helpful for diagnostic and therapeutic purposes. The water-soluble contrast medium is evacuated through the anus as well as excreted via the kidneys in some babies. This study was designed to evaluate the incidence of renal excretion after enemas using water-soluble contrast media and presume the causes. Contrast enemas using diluted water-soluble contrast media were performed in 23 patients under 2 months of age. After the enema, patients were followed with simple abdominal radiographs to assess the improvement in bowel distention, and we could also detect the presence of renal excretion of contrast media on the radiographs. Reviewing the medical records and imaging studies, including enemas and consecutive abdominal radiographs, we evaluated the incidence of renal excretion of water-soluble contrast media and counted the stay duration of contrast media in urinary tract, bladder, and colon. Among 23 patients, 12 patients (52%) experienced the renal excretion of water-soluble contrast media. In these patients, stay-in-bladder durations of contrast media were 1-3 days and stay-in-colon durations of contrast media were 1-10 days, while stay-in-colon durations of contrast media were 1-3 days in the patients not showing renal excretion of contrast media. The Mann-Whitney test for stay-in-colon durations demonstrated the later evacuation of contrast media in the patients with renal excretion of contrast media (p = 0.07). The review of the medical records showed that 19 patients were finally diagnosed as intestinal diseases, including Hirschsprung's disease, meconium ileum, meconium plug syndrome, and small bowel atresia or stenosis. Fisher's exact test between the presence of urinary excretion and intestinal diseases indicated a statistically significant difference (p = 0.04). The intestinal diseases causing bowel obstruction may increase the

  16. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer.

    Science.gov (United States)

    Baker, Matthew B; Albertazzi, Lorenzo; Voets, Ilja K; Leenders, Christianus M A; Palmans, Anja R A; Pavan, Giovanni M; Meijer, E W

    2015-02-20

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers.

  17. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    Science.gov (United States)

    Baker, Matthew B.; Albertazzi, Lorenzo; Voets, Ilja K.; Leenders, Christianus M. A.; Palmans, Anja R. A.; Pavan, Giovanni M.; Meijer, E. W.

    2015-02-01

    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers.

  18. Changes in apparent molar water volume and DKP solubility yield insights on the Hofmeister effect.

    Science.gov (United States)

    Payumo, Alexander Y; Huijon, R Michael; Mansfield, Deauna D; Belk, Laurel M; Bui, Annie K; Knight, Anne E; Eggers, Daryl K

    2011-12-15

    This study examines the properties of a 4 × 2 matrix of aqueous cations and anions at concentrations up to 8.0 M. The apparent molar water volume, as calculated by subtracting the mass and volume of the ions from the corresponding solution density, was found to exceed the molar volume of ice in many concentrated electrolyte solutions, underscoring the nonideal behavior of these systems. The solvent properties of water were also analyzed by measuring the solubility of diketopiperazine (DKP) in 2.000 M salt solutions prepared from the same ion combinations. Solution rankings for DKP solubility were found to parallel the Hofmeister series for both cations and anions, whereas molar water volume concurred with the cation series only. The results are discussed within the framework of a desolvation energy model that attributes solute-specific changes in equilibria to solute-dependent changes in the free energy of bulk water.

  19. Changes in Apparent Molar Water Volume and DKP Solubility Yield Insights on the Hofmeister Effect

    Science.gov (United States)

    Payumo, Alexander Y.; Huijon, R. Michael; Mansfield, Deauna D.; Belk, Laurel M.; Bui, Annie K.; Knight, Anne E.; Eggers, Daryl K.

    2011-01-01

    This study examines the properties of a 4 × 2 matrix of aqueous cations and anions at concentrations up to 8.0 M. The apparent molar water volume, as calculated by subtracting the mass and volume of the ions from the corresponding solution density, was found to exceed the molar volume of ice in many concentrated electrolyte solutions, underscoring the non-ideal behavior of these systems. The solvent properties of water were also analyzed by measuring the solubility of diketopiperazine (DKP) in 2.000 M salt solutions prepared from the same ion combinations. Solution rankings for DKP solubility were found to parallel the Hofmeister series for both cations and anions, whereas molar water volume concurred with the cation series only. The results are discussed within the framework of a desolvation energy model that attributes solute-specific changes in equilibria to solute-dependent changes in the free energy of bulk water. PMID:22029390

  20. Nanostructured lipid carriers versus microemulsions for delivery of the poorly water-soluble drug luteolin.

    Science.gov (United States)

    Liu, Ying; Wang, Lan; Zhao, Yiqing; He, Man; Zhang, Xin; Niu, Mengmeng; Feng, Nianping

    2014-12-10

    Nanostructured lipid carriers and microemulsions effectively deliver poorly water-soluble drugs. However, few studies have investigated their ability and difference in improving drug bioavailability, especially the factors contributed to the difference. Thus, this study was aimed at investigating their efficiency in bioavailability enhancement based on studying two key processes that occur in NLC and ME during traverse along the intestinal tract: the solubilization process and the intestinal permeability process. The nanostructured lipid carriers and microemulsions had the same composition except that the former were prepared with solid lipids and the latter with liquid lipids; both were evaluated for particle size and zeta potential. Transmission electron microscopy, differential scanning calorimetry, and X-ray diffraction were performed to characterize their properties. Furthermore, in vitro drug release, in situ intestinal absorption, and in vitro lipolysis were studied. The bioavailability of luteolin delivered using nanostructured lipid carriers in rats was compared with that delivered using microemulsions and suspensions. The in vitro analysis revealed different release mechanisms for luteolin in nanostructured lipid carriers and microemulsions, although the in situ intestinal absorption was similar. The in vitro lipolysis data indicated that digestion speed and extent were higher for microemulsions than for nanostructured lipid carriers, and that more of the former partitioned to the aqueous phase. The in vivo bioavailability analysis in rats indicated that the oral absorption and bioavailability of luteolin delivered using nanostructured lipid carriers and microemulsions were higher than those of luteolin suspensions. Nanostructured lipid carriers and microemulsions improved luteolin's oral bioavailability in rats. The rapid lipid digestion and much more drug solubilized available for absorption in microemulsions may contribute to better absorption and

  1. Experimental and modeling investigations of solubility and saturated liquid densities and viscosities for binary systems (methane +, ethane +, and carbon dioxide + 2-propanol)

    International Nuclear Information System (INIS)

    Nourozieh, Hossein; Kariznovi, Mohammad; Abedi, Jalal

    2013-01-01

    Highlights: • Solubilities of CH 4 , C 2 H 6 , and CO 2 in 2-propanol and saturated density and viscosity. • Solubility of C 2 H 6 in 2-propanol is higher than CH 4 and CO 2 . • Dissolution of CO 2 increases liquid density and reduces liquid viscosity. • Liquid density and viscosity reduces with dissolution of CH 4 and C 2 H 6 . • Solubilities and saturated liquid densities were predicted with SRK and PR EOS. -- Abstract: Solubilities of methane, ethane, and carbon dioxide in 2-propanol have been measured at the temperatures (303 and 323) K and at the pressures up to 6 MPa using an in-house designed PVT apparatus. The saturated liquid properties, density and viscosity, were also measured in each experiment. Prior to the phase equilibrium measurements, the density and viscosity of pure 2-propanol were measured at the temperatures (303 and 323) K over the pressure range (0.1 to 10) MPa. The dissolution of carbon dioxide in 2-propanol caused a decline in the viscosity of saturated liquid phase while an increase in the density of gas-expanded liquid was observed. The viscosity-pressure trends for methane- and ethane-saturated liquid viscosities were similar to carbon dioxide, but the saturated liquid densities decreased with the dissolution of methane and ethane in 2-propanol. Solubility increased with pressure and decreased with temperature for all compressed gases (methane, ethane and carbon dioxide). The experimental data were well correlated using Soave–Redlich–Kwong and Peng–Robinson equations of state. The solubilities and saturated liquid densities were well represented with both equations of state, and there is no superior equation of state for the modeling of the phase compositions and saturated liquid densities

  2. A new technique for online measurement of total and water-soluble copper (Cu) in coarse particulate matter (PM)

    International Nuclear Information System (INIS)

    Wang, Dongbin; Shafer, Martin M.; Schauer, James J.; Sioutas, Constantinos

    2015-01-01

    This study presents a novel system for online, field measurement of copper (Cu) in ambient coarse (2.5–10 μm) particulate matter (PM). This new system utilizes two virtual impactors combined with a modified liquid impinger (BioSampler) to collect coarse PM directly as concentrated slurry samples. The total and water-soluble Cu concentrations are subsequently measured by a copper Ion Selective Electrode (ISE). Laboratory evaluation results indicated excellent collection efficiency (over 85%) for particles in the coarse PM size ranges. In the field evaluations, very good agreements for both total and water-soluble Cu concentrations were obtained between online ISE-based monitor measurements and those analyzed by means of inductively coupled plasma mass spectrometry (ICP-MS). Moreover, the field tests indicated that the Cu monitor could achieve near-continuous operation for at least 6 consecutive days (a time resolution of 2–4 h) without obvious shortcomings. - Highlights: • A novel only PM sampling and Cu measuring technology is developed. • Very good particle collection efficiency for coarse PM is observed. • Excellent agreement is obtained between Cu ISE and offline ICP-MS measurements. • The new system can be continuously operated for at least 6 consecutive days. - A new technique for online measurements of Cu in coarse PM is described

  3. Water soluble (Ln3+) doped nanoparticle: Retention of strong luminescence

    Science.gov (United States)

    Attar, Tarannum Vahid; Khandpekar, Mahendra M.

    2018-04-01

    This paper deals with the synthesis of hexagonal nanoparticles of LaF3: Nd, Ho (LFNH) in the presence of LaCl3.7H2O and NH4F by precipitation method using deionized water as solvent. The nanoparticles have a nearly hexagonal shape with cell parameters, a = b = 7.0980 AU and c = 7.2300 AU and confirms with the JCPDS standard card (32-0483) of pure LaF3 crystals. The TEM results show that the average sizes of these nanoparticles are 15nm which is consistent with the sizes obtained from XRD measurements. The SEM image shows uniform size distribution of the nanoparticles. Detection of Second harmonic generation (SHG) signal together with the presence of wide transparency window (UV studies) makes LFNH suitable for optoelectronic applications. The Photoluminescence of the nanocrystals has been observed by excitation and emission spectra. The peak at 629nm indicates red up conversion fluorescence useful in applications like bioimaging and biolabelling.

  4. Modeling solubility of CO2/hydrocarbon gas in ionic liquid ([emim][FAP]) using Aspen Plus simulations.

    Science.gov (United States)

    Bagchi, Bishwadeep; Sati, Sushmita; Shilapuram, Vidyasagar

    2017-08-01

    The Peng-Robinson equation of state with quadratic van der Waals (vdW) mixing rule model was chosen to perform the thermodynamic calculations in Flash3 column of Aspen Plus to predict the solubility of CO 2 or any one of the hydrocarbons (HCs) among methane, ethane, propane, and butane in an ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([emim][FAP]). Bubble point pressure, solubility, bubble point temperature, fugacity, and partial molar volume at infinite dilution were obtained from the simulations, and enthalpy of absorption, Gibbs free energy of solvation, and entropy change of absorption were estimated by thermodynamic relations. Results show that carbon chain length has a significant effect on the bubble point pressure. Methane has the highest bubble point pressure among all the considered HCs and CO 2 . The bubble point pressure and fugacity variation with temperature is different for CO 2 as compared to HCs for mole fractions above 0.2. Two different profiles are noticed for enthalpy of absorption when plotted as a function of mole fraction of gas soluble in IL. Partial molar volume of CO 2 decreases with increase in temperature in [emim][FAP], while it is increased for HCs. Bubble point temperature decreases with increase in the mole fraction of the solute. Entropy of solvation increases with temperature till a particular value followed by a decrease with further increase in temperature. Gibbs free energy change of solvation showed that the process of solubility was spontaneous.

  5. Experimental density, viscosity, interfacial tension and water solubility of ethyl benzene-α-methyl benzyl alcohol–water system

    International Nuclear Information System (INIS)

    Barega, Esayas W.; Zondervan, Edwin; Haan, André B. de

    2013-01-01

    Highlights: • Properties were measured for MBA (methyl benzyl alcohol)-EB (ethyl benzene)-water. • MBA concentration was found to influence all the properties strongly. • The water solubility, density, and viscosity increased at high MBA concentration. • The interfacial tension decreased sharply at high MBA concentration. • MBA dictates the phase separation and mass transfer of the ternary system. -- Abstract: Density, viscosity, interfacial tension, and water solubility were measured for the (α-methyl benzyl alcohol (MBA) + Ethyl benzene (EB)) system at different concentrations of MBA in contact with water and sodium hydroxide solution (0.01 mol · kg −1 ) as aqueous phases. The properties were measured to identify the component which plays a governing role in changing the physical properties relevant to mass transfer and phase separation of the ternary system. The concentration of MBA was found to be the major factor influencing all the properties. The water solubility, the density, and the viscosity increased notably at higher concentrations of MBA; while, the interfacial tension decreased strongly. The use of 0.01 mol · kg −1 NaOH as an aqueous phase resulted in a decrease of the interfacial tension and a minor decrease in the water solubility. The density data were correlated using a quadratic mixing rule to describe the influence of concentration at any temperature. The viscosity data are correlated using the Nissan and Grunberg and Katti-Chaudhri equations. The Szyzkowski’s equation was used to correlate the interfacial tension data. The water solubility data were described using an exponential relationship. All the correlations described the experimental physical property data adequately

  6. Experimental Study of CO2 Solubility in Ionic Liquids and Polyethylene Glycols

    OpenAIRE

    Huang, Huang

    2015-01-01

    The parameter of density, viscosity are tested and fitted with the result of solubility measurement. With series of experiments, this chemical blend is considered with a good effect. The mixture of 50% tetrabutylphosphonium glycine with 50% polyethylene glycol (molecular weight: 400) is the suggested blend, and the most suitable temperature is absorption in 120C and desorption in 60C. But the solubility reduced rapidly from the second cycle of experiment, thus recycled use is not recommended.

  7. Temperature Dependence of Mineral Solubility in Water. Part 2. Alkaline and Alkaline Earth Bromides

    Science.gov (United States)

    Krumgalz, B. S.

    2018-03-01

    Databases of alkaline and alkaline earth bromide solubilities in water at various temperatures were created using experimental data from publications over about the last two centuries. Statistical critical evaluation of the created databases was produced since there were enough independent data sources to justify such evaluation. The reliable experimental data were adequately described by polynomial expressions over various temperature ranges. Using the Pitzer approach for ionic activity and osmotic coefficients, the thermodynamic solubility products for the discussed bromide minerals have been calculated at various temperature intervals and also represented by polynomial expressions.

  8. Development of an Ion-Pairing Reagent and HPLC-UV Method for the Detection and Quantification of Six Water-Soluble Vitamins in Animal Feed

    Directory of Open Access Journals (Sweden)

    Ho Jin Kim

    2016-01-01

    Full Text Available A novel and simple method for detecting six water-soluble vitamins in animal feed using high performance liquid chromatography equipped with a photodiode array detector (HPLC/PDA and ion-pairing reagent was developed. The chromatographic peaks of the six water-soluble vitamins were successfully identified by comparing their retention times and UV spectra with reference standards. The mobile phase was composed of buffers A (5 mM PICB-6 in 0.1% CH3COOH and B (5 mM PICB-6 in 65% methanol. All peaks were detected using a wavelength of 270 nm. Method validation was performed in terms of linearity, sensitivity, selectivity, accuracy, and precision. The limits of detection (LODs for the instrument employed in these experiments ranged from 25 to 197 μg/kg, and the limits of quantification (LOQs ranged from 84 to 658 μg/kg. Average recoveries of the six water-soluble vitamins ranged from 82.3% to 98.9%. Method replication resulted in intraday and interday peak area variation of <5.6%. The developed method was specific and reliable and is therefore suitable for the routine analysis of water-soluble vitamins in animal feed.

  9. Development of an Ion-Pairing Reagent and HPLC-UV Method for the Detection and Quantification of Six Water-Soluble Vitamins in Animal Feed.

    Science.gov (United States)

    Kim, Ho Jin

    2016-01-01

    A novel and simple method for detecting six water-soluble vitamins in animal feed using high performance liquid chromatography equipped with a photodiode array detector (HPLC/PDA) and ion-pairing reagent was developed. The chromatographic peaks of the six water-soluble vitamins were successfully identified by comparing their retention times and UV spectra with reference standards. The mobile phase was composed of buffers A (5 mM PICB-6 in 0.1% CH3COOH) and B (5 mM PICB-6 in 65% methanol). All peaks were detected using a wavelength of 270 nm. Method validation was performed in terms of linearity, sensitivity, selectivity, accuracy, and precision. The limits of detection (LODs) for the instrument employed in these experiments ranged from 25 to 197 μg/kg, and the limits of quantification (LOQs) ranged from 84 to 658 μg/kg. Average recoveries of the six water-soluble vitamins ranged from 82.3% to 98.9%. Method replication resulted in intraday and interday peak area variation of water-soluble vitamins in animal feed.

  10. Hydrodistillation-adsorption method for the isolation of water-soluble, non-soluble and high volatile compounds from plant materials.

    Science.gov (United States)

    Mastelić, J; Jerković, I; Blazević, I; Radonić, A; Krstulović, L

    2008-08-15

    Proposed method of hydrodistillation-adsorption (HDA) on activated carbon and hydrodistillation (HD) with solvent trap were compared for the isolation of water-soluble, non-soluble and high volatile compounds, such as acids, monoterpenes, isothiocyanates and others from carob (Certonia siliqua L.), rosemary (Rosmarinus officinalis L.) and rocket (Eruca sativa L.). Isolated volatiles were analyzed by GC and GC/MS. The main advantages of HDA method over ubiquitous HD method were higher yields of volatile compounds and their simultaneous separation in three fractions that enabled more detail analyses. This method is particularly suitable for the isolation and analysis of the plant volatiles with high amounts of water-soluble compounds. In distinction from previously published adsorption of remaining volatile compounds from distillation water on activated carbon, this method offers simultaneous hydrodistillation and adsorption in the same apparatus.

  11. Determination of the solubility parameter of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate by inverse gas chromatography.

    Science.gov (United States)

    Ma, Xiaohong; Wang, Qiang; Li, Xiaoping; Tang, Jun; Zhang, Zhengfang

    2015-11-01

    Thermodynamic properties of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM] BF4) were determined via inverse gas chromatography (IGC). Two groups of solvents with different chemical natures and polarities were used to obtain information about [BMIM] BF4-solvent interactions. The specific retention volume, molar heat of sorption, weight fraction activity coefficient, Flory-Huggins interaction parameter as well as solubility parameter were also determined in a temperature range of 333 - 373 K. The results showed that the selected solvents n-C10 to n-C12, carbon tetrachloride, cyclohexane and toluene were poor solvents for [BMIM] BF4, while dichloromethane, acetone, chloroform, methyl acetate, ethanol and methanol were favorite solvents for [BMIM] BF4. In addition, the solubility parameter of [ BMIM] BF4 was determined as 23.39 (J/cm3)0.5 by the extrapolation at 298 K. The experiment proved that IGC was a simple and accurate method to obtain the thermodynamic properties of ionic liquids. This study could be used as a reference to the application and research of the ionic liquids.

  12. Equilibrium solubility of carbon dioxide in the amine solvent system of (triethanolamine + piperazine + water)

    International Nuclear Information System (INIS)

    Chung, P.-Y.; Soriano, Allan N.; Leron, Rhoda B.; Li, M.-H.

    2010-01-01

    In this study, a new set of data for the equilibrium solubility of carbon dioxide in the amine solvent system that consists of triethanolamine (TEA), piperazine (PZ), and water is presented. Equilibrium solubility values were obtained at T = (313.2, 333.2, and 353.2) K and pressures up to 153 kPa using the vapour-recirculation equilibrium cell. The TEA concentrations in the considered ternary (solvent) mixture were (2 and 3) kmol . m -3 and those of PZ's were (0.5, 1.0, and 1.5) kmol . m -3 . The solubility data (CO 2 loading in the amine solution) obtained were correlated as a function of CO 2 partial pressure, system temperature, and amine composition via the modified Kent-Eisenberg model. Results showed that the model applied is generally satisfactory in representing the CO 2 absorption into mixed aqueous solutions of TEA and PZ.

  13. Magnetite solubility studies under simulated PWR primary-side conditions, using lithiated, hydrogenated water

    International Nuclear Information System (INIS)

    Hewett, John; Morrison, Jonathan; Cooper, Christopher; Ponton, Clive; Connolly, Brian; Dickinson, Shirley; Henshaw, Jim

    2014-01-01

    As software for modelling dissolution, precipitation, and transport of metallic species and subsequent CRUD deposition within nuclear plant becomes more advanced, there is an increasing need for accurate and reliable thermodynamic data. The solubility behaviour of magnetite is an example of such data, and is central to any treatment of CRUD solubility due to the prevalence of magnetite and nickel ferrites in CRUD. Several workers have shown the most consistent solubility data comes from once-through flowing systems. However, despite a strong consensus between the results in acidic to mildly alkaline solutions, there is disagreement between the results at approximately pH 25C 9 and higher. A programme of experimental work is on-going at the University of Birmingham, focusing on solubility of metal oxides (e.g., magnetite) in conditions relevant to PWR primary coolant. One objective of this programme is to calculate thermodynamic constants from the data obtained. Magnetite solubility from 200 to 300°C, in lithiated, hydrogenated water of pH 25C 9–11 is being studied using a once-through rig constructed of 316L stainless steel. The feedwater is pumped at 100 bar pressure through a heated bed of magnetite granules, and the output solution is collected and analysed for iron and several other metals by ICP-MS. This paper presents results from preliminary tests without magnetite granules, in which the corroding surface of the rig itself was used as the sole source of soluble iron and of dissolved hydrogen. Levels of iron were generally within an order of magnitude of literature solubility values. Comparison of results at different flow rates and temperatures, in conjunction with conclusions drawn from the published literature, suggests that this is likely due to the presence of particulate matter in a greatly under-saturated solution, compensating for the low surface area of oxide in contact with the solution. (author)

  14. Decompression-induced melting of ice IV and the liquid-liquid transition in water

    Science.gov (United States)

    Mishima, Osamu; Stanley, H. Eugene

    1998-03-01

    Although liquid water has been the focus of intensive research for over 100 years, a coherent physical picture that unifies all of the known anomalies of this liquid, is still lacking. Some of these anomalies occur in the supercooled region, and have been rationalized on the grounds of a possible retracing of the liquid-gas spinodal (metastability limit) line into the supercooled liquid region, or alternatively the presence of a line of first-order liquid-liquid phase transitions in this region which ends in a critical point,. But these ideas remain untested experimentally, in part because supercooled water can be probed only above the homogeneous nucleation temperature TH at which water spontaneously crystallizes. Here we report an experimental approach that is not restricted by the barrier imposed by TH, involving measurement of the decompression-induced melting curves of several high-pressure phases of ice in small emulsified droplets. We find that the melting curve for ice IV seems to undergo a discontinuity at precisely the location proposed for the line of liquid-liquid phase transitions. This is consistent with, but does not prove, the coexistence of two different phases of (supercooled) liquid water. From the experimental data we calculate a possible Gibbs potential surface and a corresponding equation of state for water, from the forms of which we estimate the coordinates of the liquid-liquid critical point to be at pressure Pc ~ 0.1GPa and temperature Tc ~ 220K.

  15. Solubility of nicotinic acid in water, ethanol, acetone, diethyl ether, acetonitrile, and dimethyl sulfoxide

    International Nuclear Information System (INIS)

    Gonçalves, Elsa M.; Minas da Piedade, Manuel E.

    2012-01-01

    Highlights: ► We determined the solubility of nicotinic acid in six solvents by the gravimetric method. ► We found that, regardless of the solvent, the same monoclinic solid phase was in equilibrium with the solution. ► We determined the activity coefficients of nicotinic acid in the six solvents. ► We found that the solubility trends seem to be determined by the polarity and polarizability of the solvent. - Abstract: The mole fraction equilibrium solubility of nicotinic acid in six solvents (water, ethanol, dimethyl sulfoxide, acetone, acetonitrile and diethyl ether) differing in polarity, polarizability, and hydrogen-bonding ability, was determined over the temperature range (283 to 333) K, using the gravimetric method. The results obtained led to the solubility order dimethyl sulfoxide (DMSO) ≫ ethanol > water > acetone > diethyl ether > acetonitrile. An analysis based on various solvent descriptors, indicated that this trend seems to be mainly determined by the polarity and polarizability of the solvent. The activity coefficients of nicotinic acid in the different solvents, under saturation conditions, were determined as a function of the temperature and it was found that DMSO exhibits enhanced solubility relative to an ideal solution while the opposite is observed for all other solvents. Both the solvent and the fact that nicotinic acid is primarily zwitterionic in aqueous solution and non-zwitterionic in non-aqueous media, did not affect the nature of the solid phases in equilibrium with the different solutions. Indeed, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and differential scanning calorimetry analysis indicated that, despite some differences in particle size and morphology, the starting material and the solid products obtained at the end of the solubility studies in the six solvents used in this work were all crystalline and corresponded to the same monoclinic phase.

  16. An unusual feature of uranium ore from Domiasiat, Meghalaya: presence of water soluble uranium

    International Nuclear Information System (INIS)

    Singh, A.K.; Padmanabhan, N.P.H.; Sivaramakrishnan, K.; Krishna Rao, N.

    1993-01-01

    An unusual feature of the recently discovered sandstone-type uranium deposit in Domiasiat is the presence of appreciable amount of water soluble uranium. With normal tap water at its natural pH (7.5-7.8), upto 35% of the uranium in the ore was found to be soluble during agitation in the different samples. Presence of other ions in appreciable quantities particularly SO 4 -2 Cl - and Fe +3 appear to influence the dissolution. Percolation experiments give terminal solubilization of upto 58%, but the instantaneous uranium concentration in the percolating water attains its maximum within the first few minutes of contact. A detailed study on the chemistry of uranium dissolution may throw light on the physico-chemical controls of localization of uranium in the deposit. (author). 7 refs., 3 tabs., 4 tabs

  17. Method of cross-linking polyvinyl alcohol and other water soluble resins

    Science.gov (United States)

    Phillipp, W. H.; May, C. E.; Hsu, L. C.; Sheibley, D. W. (Inventor)

    1980-01-01

    A self supporting sheet structure comprising a water soluble, noncrosslinked polymer such as polyvinyl alcohol which is capable of being crosslinked by reaction with hydrogen atom radicals and hydroxyl molecule radicals is contacted with an aqueous solution having a pH of less than 8 and containing a dissolved salt in an amount sufficient to prevent substantial dissolution of the noncrosslinked polymer in the aqueous solution. The aqueous solution is then irradiated with ionizing radiation to form hydrogen atom radicals and hydroxyl molecule radicals and the irradiation is continued for a time sufficient to effect crosslinking of the water soluble polymer to produce a water insoluble polymer sheet structure. The method has particular application in the production of battery separators and electrode envelopes for alkaline batteries.

  18. Solubility of methane in water and in a medium for the cultivation of methanotrophs bacteria

    International Nuclear Information System (INIS)

    Serra, Maria Celeste C.; Pessoa, F.L.P.; Palavra, A.M.F.

    2006-01-01

    Solubility of methane in water and in an aqueous growth medium for the cultivation of methanotrophs bacteria was determined over the temperature range 293.15 to 323.15 K and at atmospheric pressure. The measurements were carried out in a Ben-Naim/Baer type apparatus with a precision of about ±0.3%. The experimental results were determined using accurate thermodynamic relations. The mole fractions of the dissolved gas at the gas partial pressure of 101.325 kPa, the Henry coefficients at the water vapour pressure and the Ostwald coefficients at infinite dilution were obtained. A comparison between the solubility of methane in water and those observed in fermentation medium over the temperature range of 298.15 to 308.15 K has shown that this gas is about ±2.3% more soluble in water. The temperature dependence of the mole fractions of methane was also determined using the Clarke-Glew-Weiss equation and the thermodynamic quantities, Gibbs energy, enthalpy and entropy changes, associated with the dissolution process were calculated. Furthermore, the experimental Henry coefficients for methane in water are compared with those calculated by the scaled particle theory. The estimated Henry coefficients are about ±4% lower than the experimental ones

  19. SYNTHESIS AND PHYSICAL-CHEMICAL PROPERTIES OF WATER-SOLUBLE 3-BENZYLXANTHINE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    K. V. Аleksandrova

    2015-04-01

    Full Text Available Introduction Nowadays, research of novel biological active compounds with low toxicity, are carried out among different classes of organic compounds of natural and synthetic genesis. One of the main ways of these studies is search of water-soluble compounds – convenient objects for pharmacological researches. In recent years researchers paid attention to xanthine derivatives, because of their high variativity of possible chemical modification and ability to form different salts with wide spectrum of biological action. Thus, among water-soluble xanthine derivatives were found compounds with pronounced antioxidant, diuretic and analeptic properties. Primary methods of obtaining water-soluble xanthine derivatives are direct interaction of bases with xanthine molecule or insertion basic or acidic residues in positions 7 or 8 of xanthine bicycle. According from the above, search of biologically active compounds among water-soluble substituted xanthines is prospective and actual. The aim of the study was development of synthetic ways of obtaining novel water-soluble derivatives of 3-benzyl-8-methylxanthine and studying their physical and chemical properties. Material and methods Melting points of obtained compounds were determined by capillary method on PTP (M device. ІR-spectra of synthesized compounds were recorded on the Bruker Alpha device (company «Bruker» – Germany on 4000-400 sm-1 with using console ATR (direct insertion of compound. 1Н NMR-spectra were recorded on the Varian Mercury VX-200 device (company «Varian» – USA solvent – (DMSO-d6, internal standart – ТМС. Elemental analysis was made on Elementar Vario L cube device. Chromatoraphic studies were made on the plates Sorbfil-AFV-UV (company «Sobrpolimer» –Russia. Systhems for chromatography: «acetone-propanol-2» in ratio 2:3, «propanol-2-benzene» in ratio 10:1 and exersized in UV-light in wave 200-300 nm. Results and discussion We developed methodic of synthesis

  20. Separation of water from organic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Meldrum, I.G.; Villiers Naylor, T. de.

    1990-04-10

    This invention relates to the separation of water from fluids by the pervaporation process using a membrane. The invention is characterized in that the membrane has an active layer which consists essentially only of polymers of an unsaturated organic acid, the acid having not more than 6 carbon atoms for every acid group (not counting any carbon atoms in the acid groups), and the polymer having at least a substantial proportion of the acid groups in the form of a salt. The preferred fluids for use in the process of the invention are organic fluids, such as a hydrocarbon gas (in particular, methane) or a liquid. The process is especially suitable for separating water from mixtures with alkanols, in particular alkanols having 1 to 5 carbon atoms in the molecule, such as ethanol and isopropanol. The unsaturated organic acid may be a sulfur acid, such as a sulfonate or a sulfate or a phosphorus acid, but is preferably a carboxylic acid. Thus, the active layer may be poly(acrylic acid) or poly(maleic acid). The cation of the salt form of the acid groups is preferably an alkali metal, especially cesium. Experiments are described to illustrate the invention. 13 tabs.

  1. Recent advances in exploiting ionic liquids for biomolecules: Solubility, stability and applications.

    Science.gov (United States)

    Sivapragasam, Magaret; Moniruzzaman, Muhammad; Goto, Masahiro

    2016-08-01

    The technological utility of biomolecules (e.g. proteins, enzymes and DNA) can be significantly enhanced by combining them with ionic liquids (ILs) - potentially attractive "green" and "designer" solvents - rather than using in conventional organic solvents or water. In recent years, ILs have been used as solvents, cosolvents, and reagents for biocatalysis, biotransformation, protein preservation and stabilization, DNA solubilization and stabilization, and other biomolecule-based applications. Using ILs can dramatically enhance the structural and chemical stability of proteins, DNA, and enzymes. This article reviews the recent technological developments of ILs in protein-, enzyme-, and DNA-based applications. We discuss the different routes to increase biomolecule stability and activity in ILs, and the design of biomolecule-friendly ILs that can dissolve biomolecules with minimum alteration to their structure. This information will be helpful to design IL-based processes in biotechnology and the biological sciences that can serve as novel and selective processes for enzymatic reactions, protein and DNA stability, and other biomolecule-based applications. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. (Liquid + liquid) equilibria of (water + linalool + limonene) ternary system at T = (298.15, 308.15, and 318.15) K

    International Nuclear Information System (INIS)

    Gramajo de Doz, Monica B.; Cases, Alicia M.; Solimo, Horacio N.

    2008-01-01

    (Liquid + liquid) equilibrium (LLE) data for {water (1) + linalool (2) + limonene (3)} ternary system at T = (298.15, 308.15, and 318.15 ± 0.05) K are reported. The organic chemicals were quantified by gas chromatography using a flame ionisation detector while water was quantified using a thermal conductivity detector. The effect of the temperature on (liquid + liquid) equilibrium is determined and discussed. Experimental data for the ternary mixture are compared with values calculated by the NRTL and UNIQUAC equations, and predicted by means of the UNIFAC group contribution method. It is found that the UNIQUAC and NRTL models provide a good correlation of the solubility curve at these three temperatures, while comparing the calculated values with the experimental ones, the best fit is obtained with the NRTL model. Finally, the UNIFAC model provides poor results, since it predicts a greater heterogeneous region than experimentally observed

  3. Intestinal absorption of water-soluble vitamins in health and disease.

    Science.gov (United States)

    Said, Hamid M

    2011-08-01

    Our knowledge of the mechanisms and regulation of intestinal absorption of water-soluble vitamins under normal physiological conditions, and of the factors/conditions that affect and interfere with theses processes has been significantly expanded in recent years as a result of the availability of a host of valuable molecular/cellular tools. Although structurally and functionally unrelated, the water-soluble vitamins share the feature of being essential for normal cellular functions, growth and development, and that their deficiency leads to a variety of clinical abnormalities that range from anaemia to growth retardation and neurological disorders. Humans cannot synthesize water-soluble vitamins (with the exception of some endogenous synthesis of niacin) and must obtain these micronutrients from exogenous sources. Thus body homoeostasis of these micronutrients depends on their normal absorption in the intestine. Interference with absorption, which occurs in a variety of conditions (e.g. congenital defects in the digestive or absorptive system, intestinal disease/resection, drug interaction and chronic alcohol use), leads to the development of deficiency (and sub-optimal status) and results in clinical abnormalities. It is well established now that intestinal absorption of the water-soluble vitamins ascorbate, biotin, folate, niacin, pantothenic acid, pyridoxine, riboflavin and thiamin is via specific carrier-mediated processes. These processes are regulated by a variety of factors and conditions, and the regulation involves transcriptional and/or post-transcriptional mechanisms. Also well recognized now is the fact that the large intestine possesses specific and efficient uptake systems to absorb a number of water-soluble vitamins that are synthesized by the normal microflora. This source may contribute to total body vitamin nutrition, and especially towards the cellular nutrition and health of the local colonocytes. The present review aims to outline our current

  4. Enhancement of quercetin water solubility with steviol glucosides and the studies of biological properties

    Directory of Open Access Journals (Sweden)

    Thi Thanh Hanh Nguyen

    2015-12-01

    Full Text Available Background: Quercetin, a flavonol contained in various vegetables and fruits, has various biological activities including anticancer, antiviral, anti-diabetic, and anti-oxidative. However, it has low oral bioavailability due to insolubility in water. Thus, the bioavailability of quercetin administered to human beings in a capsule form, was reported to be less than 1%, with only a small percentage of ingested quercetin getting absorbed in the blood. This leads to certain difficulties in creating highly effective medicines Methods: Quercetin-rubusoside and quercetin-rebaudioside were prepared. The antioxidant activities of quercetin and Q-rubusoside were evaluated by DPPH radical scavenging method. Inhibition activities of quercetin and Quercetin-rubusoside were determined by measuring the remaining activity of 3CLpro with 200 μM inhibitor. The inhibition activity of quercetin, rubusoside and quercetin-rubusoside were determined by measuring the activity of human maltase which remains at 100 μM rubusoside or quercetin-rubusoside. The mushroom tyrosinase inhibition was assayed with the reaction mixture contained 3.3 mM L-DOPA in 50 mM potassium phosphate buffer (pH 6.8, and 10 U mushroom tyrosinase/ml with or without quercetin or quercetin-rubusoside. Results: With 10% rubusoside treatment, quercetin showed solubility of 7.7 mg/ml in water, and its solubility increased as the concentration of rubusoside increased; the quercetin solubility in water increased to 0.83 mg/mlas rubusoside concentration increased to 1 mg/ml. Quercetin solubilized in rubusoside solution showed DPPH radical-scavenging activity and mushroom tyrosinase inhibition activity, similar to that of quercetin solubilized in dimethyl-sulfoxide. Quercetin-rubusoside also showed 1.2 and 1.9 folds higher inhibition activity against 3CLpro of SARS and human intestinal maltase, respectively, than those of quercetin in DMSO. Conclusions: Quercetin can be solubilized in water with

  5. [HYGIENIC ASSESSMENT OF WATER-SOLUBLE VITAMINS CONTENT IN THE FOOD RATION OF ADOLESCENTS].

    Science.gov (United States)

    Kozubenko, O V; Turchaninov, D V; Boyarskaya, L A; Glagoleva, O N; Pogodin, I S; Luksha, E A

    2015-01-01

    Adequate, balanced nutrition is a precondition for the formation of health of the younger generation. The study of the dietary intake and peculiarities of the chemical composition offood is needed to substantiate measures aimed at the correction of the ration of adolescents. Hygienic evaluation of the content of water soluble vitamins in foods and the ration of teenage population of the Omsk region. TASKS OF THE STUDY: 1. To determine levels of water-soluble vitamins content in foods forming the basis of the ration of the population the Omsk region. 2. On the base of a study of the actual nutrition of adolescents to determine the levels of water-soluble vitamins consumption. 3. To give a hygienic assessment of adolescent nutrition in the Omsk region in terms of provision with water-soluble vitamins, and to identify priority directions of the alimentary correction of the revealed disorders. The analysis of 389 food samples for the content of water-soluble vitamins (B1, B2, B6, PP C, folic acid) was performed with the use of reversed-phase HPLC high pressure on the Shimadzu LC-20 Prominence detector. The hygienic assessment of the actual nutrition of adolescents aged 13-17 years (sample survey; n = 250; 2012-2014) in the Omsk region was performed by the method of the analysis of food consumption frequency. There were noted significantly lower concentrations of vitamin B1 and B2 in the studied samples of cereals, bread and vegetables in comparison with reference data. Consumption levels of vitamins B1, B2, PP folic acid in the diet of adolescents in the Omsk region are lower than recommended values. In the structure of nutrition there is not enough milk dairy products--in 82.4 ± 2.4%, fish and sea products in 90.8 ± 1.8% of adolescents. The actual nutrition of the adolescent population of the Omsk region is irrational, unbalanced in quantitative and qualitative terms, and does not provide the necessary level of consumption of most important water-soluble vitamins

  6. Modified ionic liquid cold-induced aggregation dispersive liquid-liquid microextraction followed by atomic absorption spectrometry for trace determination of zinc in water and food samples

    International Nuclear Information System (INIS)

    Zeeb, M.; Sadeghi, M.

    2011-01-01

    We report on a new method for the microextraction and determination of zinc (II). The ion is accumulated via ionic-liquid cold-induced aggregation dispersive liquid-liquid microextraction (IL-CIA-DLLME) followed by flame atomic absorption spectrometry (FAAS). The ionic liquid (IL) 1-hexyl-3-methylimidazolium hexafluorophosphate is dispersed into a heated sample solution containing sodium hexafluorophosphate as a common ion source. The solution is then placed in an ice-water bath upon which a cloudy solution forms due to the decrease of the solubility of the IL. Zinc is complexed with 8-hydroxyquinoline and extracted into the IL. The enriched phase is dissolved in a diluting agent and introduced to the FAAS. The method is not influenced by variations in the ionic strength of the sample solution. Factors affecting the performance were evaluated and optimized. At optimum conditions, the limit of detection is 0.18 μg L -1 , and the relative standard deviation is 3.0% (at n=5). The method was validated by recovery experiments and by analyzing a certified reference material and successfully applied to the determination of Zn (II) in water and food samples. (author)

  7. Controlling the photochemical reaction of an azastilbene derivative in water using a water-soluble pillar[6]arene.

    Science.gov (United States)

    Xia, Danyu; Wang, Pi; Shi, Bingbing

    2017-09-20

    Photochemistry plays an important role in our lives. It has also been a common tool in the laboratory to construct complicated systems from small molecules. Supramolecular chemistry provides an opportunity to solve some of the problems in controlling photochemical reactions via non-covalent interactions. By using confining media and weak interactions between the medium and the reactant molecule, the excited state behavior of molecules has been successfully manipulated. Pillararenes, a new class of macrocyclic hosts, have rarely been used in the field of photochemical investigations, such as the controlling of photo-induced reactions. Herein, we explore a synthetic macrocyclic host, a water-soluble pillar[6]arene, as a controlling tool to manipulate the photo-induced reactions (hydration) in water. A host-guest system in water based on a water-soluble pillar[6]arene and an azastilbene derivative, (E)-4,4'-dimethyl-4,4'-diazoniastilbene diiodide, has been constructed. Then this water-soluble pillar[6]arene was successfully employed to control the photohydration of the azastilbene derivative in water as a "protective agent".

  8. Spray Freeze-drying - The Process of Choice for Low Water Soluble Drugs?

    International Nuclear Information System (INIS)

    Leuenberger, H.

    2002-01-01

    Most of the novel highly potent drugs, developed on the basis of modern molecular medicine, taking into account cell surface recognition techniques, show poor water solubility. A chemical modification of the drug substance enhancing the solubility often decreases the pharmacological activity. Thus, as an alternative an increase of the solubility can be obtained by the reduction of the size of the drug particles. Unfortunately, it is often difficult to obtain micro or nanosized drug particles by classical or more advanced crystallization using supercritical gases or by milling techniques. In addition, nanosized particles are often not physically stable and need to be stabilized in an appropriate matrix. Thus, it may be of interest to manufacture directly nanosized drug particles stabilized in an inert hydrophilic matrix, i.e. nanostructured and nanocomposite systems. Solid solutions and solid dispersions represent nanostructured and nanocomposite systems. In this context, the use of the vacuum-fluidized-bed technique for the spray-drying of a low water soluble drug cosolubilized with a hydrophilic excipient in a polar organic solvent is discussed. In order to avoid the use of organic solvents, a special spray-freeze-drying technique working at atmospheric pressure is presented. This process is very suitable for temperature and otherwise sensitive drugs such as pharmaproteins

  9. An effect of cation functionalization on thermophysical properties of ionic liquids and solubility of glucose in them – Measurements and PC-SAFT calculations

    International Nuclear Information System (INIS)

    Paduszyński, Kamil; Okuniewski, Marcin; Domańska, Urszula

    2016-01-01

    Highlights: • Density, viscosity and DSC thermograms for four ionic liquids were measured. • New data on solubility of glucose in ionic liquids were presented. • An impact of cation functionalization on solubility was established. • Apparent thermodynamic functions of dissolution were determined. • Modeling of the studied systems with PC-SAFT equation of state was performed. - Abstract: This contribution is concerned with thermodynamic investigation on thermophysical properties of four ionic liquids based on dicyanamide anion. The ionic liquids under study differ in substituent attached to imidazolium cation, so that an impact of terminal functional groups on the considered properties is established. Discussion is presented in terms of molecular packing and interactions (polarity, hydrogen bonding) between molecules forming system. Differential scanning calorimetry thermograms, density and viscosity were the investigated properties of pure ionic liquids. Moreover, new data sets on solubility of glucose in ionic liquids are presented. Analysis of the temperature-dependent solubility data by means of modified Van’t Hoff equation is given and apparent thermodynamic functions of dissolution are calculated. Thermodynamic modeling of the (solid + liquid) equilibrium phase diagrams was carried out by means of perturbed-chain statistical associating fluid theory (PC-SAFT). It is evidenced that consistent and accurate thermodynamic description of complex cross-associating {ionic liquid + sugar} systems can be achieved by using simple (but physically grounded) molecular schemes, assuming that two adjustable binary corrections are introduced.

  10. Production of a water-soluble fertilizer containing amino acids by solid-state fermentation of soybean meal and evaluation of its efficacy on the rapeseed growth.

    Science.gov (United States)

    Wang, Jianlei; Liu, Zhemin; Wang, Yue; Cheng, Wen; Mou, Haijin

    2014-10-10

    Soybean meal is a by-product of soybean oil extraction and contains approximately 44% protein. We performed solid-state fermentation by using Bacillus subtilis strain N-2 to produce a water-soluble fertilizer containing amino acids. Strain N-2 produced a high yield of protease, which transformed the proteins in soybean meal into peptide and free amino acids that were dissolved in the fermentation products. Based on the Plackett-Burman design, the initial pH of the fermentation substrate, number of days of fermentation, and the ratio of liquid to soybean meal exhibited significant effects on the recovery of proteins in the resulting water-soluble solution. According to the predicted results of the central composite design, the highest recovery of soluble proteins (99.072%) was achieved at the optimum conditions. Under these conditions, the resulting solution contained 50.42% small peptides and 7.9% poly-γ-glutamic acid (γ-PGA). The water-soluble fertilizer robustly increased the activity of the rapeseed root system, chlorophyll content, leaf area, shoot dry weight, root length, and root weight at a concentration of 0.25% (w/v). This methodology offers a value-added use of soybean meal. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Application To Bilayer System With Water-Soluble Contrast Enhancing Material

    Science.gov (United States)

    Yabuta, Mitsuo; Ito, Naoki; Yamazaki, Hiroyuki; Nakayama, Toshimasa

    1987-09-01

    We have developed ,a water-soluble contrast enhancing material, TAD-436 ( Tokyo Ohka. Anti-Defocus Material ) which is consisted of a water-soluble diazonium salt as bleaching compounds and a water-soluble anion type polymer as binder polymers. Needless to say that water is used as solvent in TAD; therefore, it can be spincoated directly on a positive photoresist layer of a quinonediazide-novolak resin type without causing intermixing and furtheremore the bilayer can be developed without stripping TAD immediately after exposure. TAD shows a satisfactory bleaching characteristics on g-line, increases r-value of underlying photoresist and reduces the thickness loss of photoresist layer in unexposed area. Application to bilayer system with TAD will raise the resolution of underlying photoresist and when the focus depth is changed it will make the change in the resist profile small. As the result of it, the notches in the resist patterns on steps is reduced, making the difference in the linewidth between the top and the bottom of steps small.

  12. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    Science.gov (United States)

    Karicheva, E.; Guseva, N.; Kambalina, M.

    2016-03-01

    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  13. Synthesis and properties of amino acid functionalized water-soluble perylene diimides

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yongshan; Li, Xuemei; Wei, Xiaofeng; Jiang, Tianyi; Wu, Junsen; Ren, Huixue [Shandong Jianzhu University, Jinan (China)

    2015-07-15

    We prepared amino acid functionalized water-soluble perylene diimides: N,N'-bi(L-glutamic acid)-perylene-3,4;9,10-dicarboxylic diimide (1), N,N'-bi(L-phenylalanine acid)-perylene-3,4;9,10-dicarboxylic diimide (2), N,N'-bi(Lglutamic amine)-perylene-3,4;9,10-dicarboxylic diimide (3) and N,N'-bi(L-phenylalanine amine)-perylene-3,4;9,10-dicarboxylic diimide (4). The structures of 3 and 4 were confirmed by {sup 1}H NMR, FT-IR and MS. The maximal absorption bands of compound 1 and 2 in concentrated sulfuric acid were red-shifted for about 48 and 74 nm, respectively, compared with that of Perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCDA). Nearly no fluorescence was observed for compounds 1 and 2 in water, while compounds 3 and 4 were significantly water-soluble and had very high fluorescent quantum. The mechanism of the optical properties change was discussed, and the π-π stacking caused by H{sup +} led to the changes of fluorescence spectrum and absorption spectrum. The calculated molecular orbital energies and the frontier molecular orbital maps of compounds 1-2 based on density function theory (DFT) calculations were reported. Owing to the high water-soluble, the perylene derivatives 3 and 4 were successfully applied as high-performance fluorochromes for living hela cells imaging.

  14. Geochemical evidence of water-soluble gas accumulation in the Weiyuan gas field, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Shengfei Qin

    2016-01-01

    Full Text Available At present, there are several different opinions on the formation process of the Weiyuan gas field in the Sichuan Basin and the source of its natural gas. In view of the fact that the methane carbon isotope of the natural gas in the Weiyuan gas field is abnormally heavy, the geologic characteristics of gas reservoirs and the geochemical characteristics of natural gas were first analyzed. In the Weiyuan gas field, the principal gas reservoirs belong to Sinian Dengying Fm. The natural gas is mainly composed of methane, with slight ethane and trace propane. The gas reservoirs are higher in water saturation, with well preserved primary water. Then, it was discriminated from the relationship of H2S content vs. methane carbon isotope that the heavier methane carbon isotope of natural gas in this area is not caused by thermochemical sulfate reduction (TSR. Based on the comparison of methane carbon isotope in this area with that in adjacent areas, and combined with the tectonic evolution background, it is regarded that the natural gas in the Weiyuan gas field is mainly derived from water-soluble gas rather than be migrated laterally from adjacent areas. Some conclusions are made. First, since methane released from water is carbon isotopically heavier, the water-soluble gas accumulation after degasification results in the heavy methane carbon isotope of the gas produced from Weiyuan gas field. Second, along with Himalayan movement, great uplift occurred in the Weiyuan area and structural traps were formed. Under high temperature and high pressure, the gas dissolved in water experienced decompression precipitation, and the released natural gas accumulated in traps, consequently leading to the formation of Weiyuan gas field. Third, based on calculation, the amount of natural gas released from water which is entrapped in the Weiyuan gas field after the tectonic uplift is basically equal to the proved reserves of this field, confirming the opinion of water-soluble

  15. Combined Measurement of 6 Fat-Soluble Vitamins and 26 Water-Soluble Functional Vitamin Markers and Amino Acids in 50 μL of Serum or Plasma by High-Throughput Mass Spectrometry.

    Science.gov (United States)

    Midttun, Øivind; McCann, Adrian; Aarseth, Ove; Krokeide, Marit; Kvalheim, Gry; Meyer, Klaus; Ueland, Per M

    2016-11-01

    Targeted metabolic profiling characterized by complementary platforms, multiplexing and low volume consumption are increasingly used for studies using biobank material. Using liquid-liquid extraction, we developed a sample workup suitable for quantification of 6 fat- and 26 water-soluble biomarkers. 50 μL of serum/plasma was mixed with dithioerythritol, ethanol, and isooctane/chloroform. The organic layer was used for analysis of the fat-soluble vitamins all-trans retinol (A), 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, α-tocopherol (E), γ-tocopherol (E), and phylloquinone (K1) by LC-MS/MS. The remaining aqueous fraction was mixed with ethanol, water, pyridine, and methylchloroformate (in toluene) to derivatize the water-soluble biomarkers. The resulting toluene layer was used for GC-MS/MS analysis of alanine, α-ketoglutarate, asparagine, aspartic acid, cystathionine, total cysteine, glutamic acid, glutamine, glycine, histidine, total homocysteine, isoleucine, kynurenine, leucine, lysine, methionine, methylmalonic acid, ornithine, phenylalanine, proline, sarcosine, serine, threonine, tryptophan, tyrosine, and valine. Isotope-labeled internal standards were used for all analytes. Chromatographic run times for the LC-MS/MS and GC-MS/MS were 4.5 and 11 min, respectively. The limits of detection (LOD) for the low-concentration analytes (25-hydroxyvitamin D2, 25-hydroxyvitamin D3, and phylloquinone) were 25, 17, and 0.33 nM, respectively, while all other analytes demonstrated sensitivity significantly lower than endogenous concentrations. Recoveries ranged from 85.5-109.9% and within- and between-day coefficients of variance (CVs) were 0.7-9.4% and 1.1-17.5%, respectively. This low-volume, high-throughput multianalyte assay is currently in use in our laboratory for quantification of 32 serum/plasma biomarkers in epidemiological studies.

  16. Phase equilibria of didecyldimethylammonium nitrate ionic liquid with water and organic solvents

    International Nuclear Information System (INIS)

    Domanska, Urszula; Lugowska, Katarzyna; Pernak, Juliusz

    2007-01-01

    The phase diagrams for binary mixtures of an ammonium ionic liquid, didecyldimethylammonium nitrate, [DDA][NO 3 ], with: alcohols (propan-1-ol, butan-1-ol, octan-1-ol, and decan-1-ol): hydrocarbons (toluene, propylbenzene, hexane, and hexadecane) and with water were determined in our laboratory. The phase equilibria were measured by a dynamic method from T 220 K to either the melting point of the ionic liquid, or to the boiling point of the solvent. A simple liquidus curve in a eutectic system was observed for [DDA][NO 3 ] with: alcohols (propan-1-ol, butan-1-ol, and octan-1-ol); aromatic hydrocarbons (toluene and propylbenzene) and with water. (Solid + liquid) equilibria with immiscibility in the liquid phase were detected with the aliphatic hydrocarbons heptane and hexadecane and with decan-1-ol. (Liquid + liquid) equilibria for the system [DDA][NO 3 ] with hexadecane was observed for the whole mole fraction range of the ionic liquid. The observation of the upper critical solution temperature in binary mixtures of ([DDA][NO 3 ] + decan-1-ol, heptane, or hexadecane) was limited by the boiling temperature of the solvent. Characterisation and purity of the compounds were determined by elemental analysis, water content (Fisher method) and differential scanning microcalorimetry (d.s.c.) analysis. The d.s.c. method of analysis was used to determine melting temperatures and enthalpies of fusion. The thermal stability of the ionic liquid was resolved by the thermogravimetric technique-differential thermal analysis (TG-DTA) technique over a wide temperature range from (200 to 780) K. The thermal decomposition temperature of 50% of the sample was greater than 500 K. The (solid + liquid) phase equilibria, curves were correlated by means of different G Ex models utilizing parameters derived from the (solid + liquid) equilibrium. The root-mean-square deviations of the solubility temperatures for all calculated data are dependent upon the particular system and the particular

  17. Simple multipurpose apparatus for solubility measurement of solid solutes in liquids

    DEFF Research Database (Denmark)

    Malwade, Chandrakant Ramkrishna; Christensen, Lars Porskjær

    2016-01-01

    students of chemical engineering program at University of Southern Denmark. The exercises included solubility measurement and cooling crystallization of salicylic acid from five different organic solvents and extraction of artemisinin from the leaves of the plant Artemisia annua by using different solvents...

  18. Extraction of butan-1-ol from water with ionic liquids at T = 308.15 K

    International Nuclear Information System (INIS)

    Domańska, Urszula; Królikowski, Marek

    2012-01-01

    Highlights: ► The LLE ternary phase diagrams with ionic liquids were measured. ► Separation of butan-1-ol/water system with tetracyanoborate-based ILs. ► Low solubility of water in [P 14,6,6,6 ][TCB] was observed. ► [P 14,6,6,6 ][TCB] is proposed for possible use in separation of butan-1-ol from aqueous phase. - Abstract: Ionic liquids (ILs) are novel green solvents that can be proposed for removing butan-1-ol from the aqueous fermentation media. Ternary (liquid + liquid) equilibrium data are presented for {ionic liquid (1) + butan-1-ol (2) + water (3)} at T = 308.15 K and ambient pressure to analyze the performance of the ionic liquid (IL) in the extraction of butan-1-ol from aqueous phase. The tetracyanoborate-based ILs have been studied: 1-hexyl-3-methylimidazolium tetracyanoborate, ([HMIM][TCB]), 1-decyl-3-methylimidazolium tetracyanoborate, ([DMIM][TCB]) and trihexyltetradecylphosphonium tetracyanoborate, ([P 14,6,6,6 ][TCB]). The results are discussed in terms of the selectivity and distribution ratio of separation of related systems. The complete miscibility in the binary liquid systems of butan-1-ol with all used ILs was observed. The imidazolium cation in comparison with phosphonium cation shows lower selectivity and distribution ratio. The IL with the longer alkyl chain at the cation shows higher selectivity and distribution ratio in this process. The non-random two liquid NRTL model was used successfully to correlate the experimental tie-lines and to calculate the phase composition error in mole fraction in the ternary systems. The average root mean square deviation (RMSD) of the phase composition was 0.0027. The data presented here indicates the usefulness of [P 14,6,6,6 ][TCB] as a solvent for the separation of butan-1-ol from water using solvent extraction. The density of [P 14,6,6,6 ][TCB] was measured as a function of temperature.

  19. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Directory of Open Access Journals (Sweden)

    Qing-Xi Wu

    2014-12-01

    Full Text Available Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  20. Design of chitosan and its water soluble derivatives-based drug carriers with polyelectrolyte complexes.

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-12-19

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  1. Solubilities of some hydrous REE phosphates with implications for diagenesis and sea water concentrations

    International Nuclear Information System (INIS)

    Jonasson, R.G.; Bancroft, G.M.; Nesbitt, H.W.

    1985-01-01

    Solubility product determinations suggest that the hydrous phosphates of the rare earths, REPO 4 .xH 2 O, are important in controlling the sea water REE concentrations. Two of these solids, rhabdophane, (P6 2 22) and 'hydrous xenotime', (I4 1 /amd), have been synthesized at 100 C via the acid hydrolysis of the respective REE pyrophosphate. The solubility products at infinite dilution were determined to be pK 0 = 24.5, (La at 25 C); 26.0, (Pr at 100 C); 25.7, (Nd at 100 C); and 25.5, (Er at 100 C). On the basis of calculations involving the reaction of Re 3+ with apatite to form the hydrous phosphate, the lanthanum concentration in sea water is predicted to be about 140 pmol/L. Laboratory experiments support the hypothesis that apatite is a substrate for reactions with dissolved REE. (author)

  2. Synthesis and characterization of a hyper-branched water-soluble β-cyclodextrin polymer

    Directory of Open Access Journals (Sweden)

    Francesco Trotta

    2014-11-01

    Full Text Available A new hyper-branched water-soluble polymer was synthesized by reacting β-cyclodextrin with pyromellitic dianhydride beyond the critical conditions that allow the phenomenon of gelation to occur. The molar ratio between the monomers is a crucial parameter that rules the gelation process. Nevertheless, the concentration of monomers in the solvent phase plays a key role as well. Hyper-branched β-cyclodextrin-based polymers were obtained performing the syntheses with excess of solvent and cross-linking agent, and the conditions for critical dilution were determined experimentally. A hyper-branched polymer with very high water solubility was obtained and fully characterized both as for its chemical structure and for its capability to encapsulate substances. Fluorescein was used as probe molecule to test the complexation properties of the new material.

  3. Analytical procedures for water-soluble vitamins in foods and dietary supplements: a review.

    Science.gov (United States)

    Blake, Christopher J

    2007-09-01

    Water-soluble vitamins include the B-group vitamins and vitamin C. In order to correctly monitor water-soluble vitamin content in fortified foods for compliance monitoring as well as to establish accurate data banks, an accurate and precise analytical method is a prerequisite. For many years microbiological assays have been used for analysis of B vitamins. However they are no longer considered to be the gold standard in vitamins analysis as many studies have shown up their deficiencies. This review describes the current status of analytical methods, including microbiological assays and spectrophotometric, biosensor and chromatographic techniques. In particular it describes the current status of the official methods and highlights some new developments in chromatographic procedures and detection methods. An overview is made of multivitamin extractions and analyses for foods and supplements.

  4. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail. PMID:25532565

  5. Studies on water soluble polysaccharides from Pithecellobium dulce (Roxb.) Benth. seeds.

    Science.gov (United States)

    Bagchi, S; Kumar, K Jayaram

    2016-03-15

    In this existing experimental work, water soluble PDP polysaccharides were secluded from Pithecellobium dulce (Roxb.) Benth. seeds. The physicochemical properties were analyzed in terms of swelling power, solubility, pH and water holding capacity. Micromeretic studies proved the polysaccharide may be used a potential pharmaceutical adjuvant. The polysaccharide was characterized by FT-IR, SEM, TGA and NMR techniques. Methylation analysis confirmed that the polysaccharide is composed of Arabinose (Araf) units. The chemical shifts of anomeric proton region were found in the region of 4.4-5.5ppm. Thermogravimetric analysis showed that PDP polysaccharide was thermally stable. The in vitro antioxidant capacities of the polysaccharide were investigated in terms of scavenging of hydroxyl radicals, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydrogen peroxide (H2O2) and reducing power assay. The polysaccharide fractions showed activity in a concentration dependent manner which was comparable to the standard, ascorbic acid. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Application of radiation grafting techniques to prepare the high molecular weight water-soluble polymer

    International Nuclear Information System (INIS)

    Le Hai; Nguyen Quoc Hien; Nguyen Tan Man; Truong Thi Hanh; Le Huu Tu; Tran Thi Tam; Pham Thi Sam; Pham Anh Tuan; Le Dinh Lang

    2003-01-01

    The results of the study on the preparation of the high molecular weight water-soluble polymers by radiation grafting and their properties is presented as follows: 1/ by radiation grafting, the molecular weight of PVA was increased 20 times and PAM was increased only 3 times; 2/ the thermal and medium stability of poly(vinyl alcohol) grafted with acrylamide was obviously improved. (LH)

  7. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    OpenAIRE

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have...

  8. Natural polymers: Best carriers for improving bioavailability of poorly water soluble drugs in solid dispersions

    OpenAIRE

    Sandip Sapkal; Mahesh Narkhede; Mukesh Babhulkar; Gautam Mehetre; Ashish Rathi

    2013-01-01

    ABSTRACTNatural polymers and its modified forms can be used as best alternative for improving bioavailabilityof poorly water soluble drugs in solid dispersion. Most of the natural polymersare hydrophilic and having high swelling capacity. Recent trend towards the use of naturalpolymer demands the replacement of synthetic additives with natural ones. Many plant derivednatural polymers are studied for use in solid dispersion systems, out of which naturalgums, cyclodextrin and carbohydrate are m...

  9. Indirect caudal lymphography using a new water-soluble contrast agent - animal experimental studies in pigs

    International Nuclear Information System (INIS)

    Apitzsch, D.E.; Kroll, H.U.; Zuehlke, H.V.

    1981-01-01

    Animal experiments on caudal lymphography in pigs are presented, using a new water-soluble contrast medium which is renally excreted. Indirect cutaneous administration renders possible the radiological visualization of the entire lymphatic drainage system of the lower limb, the retro-peritoneal space and the thoracic duct. Visualization of the lymphatic system is rapid, homogeneous and can be repeated as often as desired. The quality of the lymphogram is as good as that obtained by the current methods in common use. (orig.)

  10. Changing oxidoreduction potential to improve water-soluble yellow pigment production with Monascus ruber CGMCC 10910.

    Science.gov (United States)

    Huang, Tao; Tan, Hailing; Lu, Fangju; Chen, Gong; Wu, Zhenqiang

    2017-11-21

    Monascus pigments are widely used in the food and pharmaceutical industries due to their safety to human health. Our previous study found that glucose concentration induced extracellular oxidoreduction potential (ORP) changes could influence extracellular water-soluble yellow pigment production by Monascus ruber CGMCC 10910 in submerged fermentation. In this study, H 2 O 2 and dithiothreitol (DTT) were used to change the oxidoreduction potential for investigating the effects of oxidative or reductive substances on Monascus yellow pigment production by Monascus ruber CGMCC 10910. The extracellular ORP could be controlled by H 2 O 2 and DTT. Both cell growth and extracellular water-soluble yellow pigment production were enhanced under H 2 O 2 -induced oxidative (HIO) conditions and were inhibited under dithiothreitol-induced reductive conditions. By optimizing the amount of H 2 O 2 added and the timing of the addition, the yield of extracellular water-soluble yellow pigments significantly increased and reached a maximum of 209 AU, when 10 mM H 2 O 2 was added on the 3rd day of fermentation with M. ruber CGMCC 10910. Under HIO conditions, the ratio of NADH/NAD+ was much lower than that in the control group, and the expression levels of relative pigment biosynthesis genes were up-regulated; moreover, the activity of glucose-6-phosphate dehydrogenase (G6PDH) was increased while 6-phosphofructokinase (PFK) activity was inhibited. Oxidative conditions induced by H 2 O 2 increased water-soluble yellow pigment accumulation via up-regulation of the expression levels of relative genes and by increasing the precursors of pigment biosynthesis through redirection of metabolic flux. In contrast, reductive conditions induced by dithiothreitol inhibited yellow pigment accumulation. This experiment provides a potential strategy for improving the production of Monascus yellow pigments.

  11. Biosynthetic Studies on Water-Soluble Derivative 5c (DTX5c

    Directory of Open Access Journals (Sweden)

    José J. Fernández

    2012-10-01

    Full Text Available The dinoflagellate Prorocentrum belizeanum is responsible for the production of several toxins involved in the red tide phenomenon known as Diarrhetic Shellfish Poisoning (DSP. In this paper we report on the biosynthetic origin of an okadaic acid water-soluble ester derivative, DTX5c, on the basis of the spectroscopical analysis of 13C enriched samples obtained by addition of labelled sodium [l-13C], [2-13C] acetate to artificial cultures of this dinoflagellate.

  12. Effect of New Water-Soluble Dendritic Phthalocyanines on Human Colorectal and Liver Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Ebru YABAŞ

    2017-08-01

    Full Text Available Human hepatocellular carcinoma (HepG2 cells and colorectal adenocarcinoma (DLD-1 cells were treated with the synthesized water soluble phthalocyanine derivatives to understand the effect of the compounds both on colorectal and liver cancer cells. The compounds inhibited cell proliferation and displayed cytotoxic effect on these cancer cell lines however; the effect of the compounds on healthy control fibroblast cell line was comparatively lower. The compounds can be employed for cancer treatment as anticancer agents.

  13. Preparation and characterization of complexes of RE3+ with furfural modified water-soluble chitosan

    Institute of Scientific and Technical Information of China (English)

    WANG Maoyuan; QIU Ligan; MA Guilin

    2008-01-01

    Degraded chitosan, with highly water-solubility, was obtained by the oxidation of chitosan with H2O2, and then reacted with furfural The final product coordinated with the rare earth ions (RE3+ = Sm3+,Eu3+), which led to the formation of the complexes. The prepared complexes were characterized with Inflated Spectroscopy (IR), Ultra Violet (UV), fluorescence, X-Ray Diffraction (XRD), and Thermogravimetric-Differential Scanning Calorimetry (TG-DSC) measurements.

  14. Solubility and thermodynamic behavior of vanillin in propane-1,2-diol+water cosolvent mixtures at different temperatures.

    Science.gov (United States)

    Shakeel, Faiyaz; Haq, Nazrul; Siddiqui, Nasir A; Alanazi, Fars K; Alsarra, Ibrahim A

    2015-12-01

    The solubilities of bioactive compound vanillin were measured in various propane-1,2-diol+water cosolvent mixtures at T=(298-318)K and p=0.1 MPa. The experimental solubility of crystalline vanillin was determined and correlated with calculated solubility. The results showed good correlation of experimental solubilities of crystalline vanillin with calculated ones. The mole fraction solubility of crystalline vanillin was recorded highest in pure propane-1,2-diol (7.06×10(-2) at 298 K) and lowest in pure water (1.25×10(-3) at 298 K) over the entire temperature range investigated. Thermodynamic behavior of vanillin in various propane-1,2-diol+water cosolvent mixtures was evaluated by Van't Hoff and Krug analysis. The results showed an endothermic, spontaneous and an entropy-driven dissolution of crystalline vanillin in all propane-1,2-diol+water cosolvent mixtures. Based on solubility data of this work, vanillin has been considered as soluble in water and freely soluble in propane-1,2-diol. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Water-soluble derivatives of 25-OCH3-PPD and their anti-proliferative activities.

    Science.gov (United States)

    Zhou, Wu-Xi; Sun, Yuan-Yuan; Yuan, Wei-Hui; Zhao, Yu-Qing

    2017-05-01

    (20R)-25-Methoxyl-dammarane-3β,12β,20-triol (25-OCH 3 -PPD, AD-1) is a dammarane-type sapogenin showing anti-tumor potential. In the search for new anti-tumor agents with higher potency than our previously identified compound 25-OCH 3 -PPD, 11 novel sulfamic acid and diacid derivatives that could improve water solubility and contribute to good drug potency and pharmacokinetic profiles were designed and synthesized. Their in vitro anti-tumor activities in MCF-7, A-549, HCT-116, and BGC-823 cell lines and one normal cell line were tested by standard MTT assay. Results showed that compared with compound 25-OCH 3 -PPD, compounds 1, 4, and 5 exhibited higher cytotoxic activity on almost all cell lines, together with lower toxicity in the normal cell. In particular, compound 1 exhibited the best anti-tumor activity in the in vitro assays. The water solubility of 25-OCH 3 -PPD and its derivatives was tested and the results showed that the solubility of 25-OCH 3 -PPD sulfamic acid and diacid derivatives were better than that of 25-OCH 3 -PPD in water, which may provide valuable data for the research and development of new anti-tumor agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Studies on Dissolution Enhancement of Prednisolone, a Poorly Water-Soluble Drug by Solid Dispersion Technique

    Directory of Open Access Journals (Sweden)

    Parvin Zakeri-Milani

    2011-06-01

    Full Text Available Introduction: Prednisolone is a class II substance according to the Biopharmaceutics Classification System. It is a poorly water soluble agent. The aim of the present study was to improve dissolution rate of a poorly water-soluble drug, prednisolone, by a solid dispersion technique. Methods: Solid dispersion of prednisolone was prepared with PEG 6000 or different carbohydrates such as lactose and dextrin with various ratios of the drug to carrier i.e., 1:10, 1:20 and 1:40. Solid dispersions were prepared by coevaporation method. The evaluation of the properties of the dispersions was performed using dissolution studies, Fourier-transform infrared spectroscopy and x-ray powder diffractometery. Results: The results indicated that lactose is suitable carriers to enhance the in vitro dissolution rate of prednisolone. The data from the x-ray diffraction showed that the drug was still detectable in its solid state in all solid dispersions except solid dispersions prepared by dextrin as carrier. The results from infrared spectroscopy showed no well-defined drug–carrier interactions for coevaporates. Conclusion: Solid dispersion of a poorly water-soluble drug, prednisolone may alleviate the problems of delayed and inconsistent rate of dissolution of the drug.

  17. Synthesis of water-soluble curcumin derivatives and their inhibition on lysozyme amyloid fibrillation

    Science.gov (United States)

    Wang, Sujuan; Peng, Xixi; Cui, Liangliang; Li, Tongtong; Yu, Bei; Ma, Gang; Ba, Xinwu

    2018-02-01

    The potential application of curcumin was heavily limited in biomedicine because of its poor solubility in pure water. To circumvent the detracting feature, two novel water-soluble amino acid modified curcumin derivatives (MLC and DLC) have been synthesized through the condensation reaction between curcumin and Nα-Fmoc-Nε-Boc-L-lysine. Benefiting from the enhanced solubility of 3.32 × 10- 2 g/mL for MLC and 4.66 × 10- 2 g/mL for DLC, the inhibition effects of the as-prepared derivatives on the amyloid fibrillation of lysozyme (HEWL) were investigated detaily in water solution. The obtained results showed that the amyloid fibrillation of HEWL was inhibited to a great extent when the concentrations of MLC and DLC reach to 20.139 mM and 49.622 mM, respectively. The fluorescence quenching upon the addition of curcumin to HEWL provide a support for static and dynamic recombination quenching process. The binding driving force was assigned to classical hydrophobic interaction between curcumin derivatives and HEWL. In addition, UV-Vis absorption and circular dichroism (CD) spectra confirmed the change of the conformation of HEWL.

  18. Water-soluble elements in atmospheric particulate matter over tropical and equatorial Atlantic

    International Nuclear Information System (INIS)

    Buat-Menard, Patrick; Morelli, Jacques; Chesselet, Roger

    1974-01-01

    Samples of water-soluble atmospheric particulate matter collected from R/V ''Jean Charcot'' (May to October 1971) and R/V ''James Gilliss'' (October 1972) over Tropical and Equatorial Atlantic were analyzed for Na, Mg, K and Ca by atomic absorption and for Cl and S as SO 4 by colorimetry. Data shows a strong geographical dependence of K and Ca enrichment relative to their elemental ratio to Na in sea-water. Ca enrichment is related to presence of identified soluble calcium minerals in continental dust originating from African deserts (Sahara-Kalahari). This dust does not influence amounts of K in the water-soluble phase. When observed, strong K enrichment appears tightly associated with high concentrations of surface-active organic material in the microlayer derived from high biological activity (Gulf of Guinea). Observed in same samples, SO 4 enrichment could also be controlled by the same source. This SO 4 enrichment balances the observed Cl loss in aerosols accordingly with gaseous HCl formation processes in marine atmosphere [fr

  19. Synthesis of water soluble glycine capped silver nanoparticles and their surface selective interaction

    International Nuclear Information System (INIS)

    Agasti, Nityananda; Singh, Vinay K.; Kaushik, N.K.

    2015-01-01

    Highlights: • Synthesis of water soluble silver nanoparticles at ambient reaction conditions. • Glycine as stabilizing agent for silver nanoparticles. • Surface selective interaction of glycine with silver nanoparticles. • Glycine concentration influences crystalinity and optical property of silver nanoparticles. - Abstract: Synthesis of biocompatible metal nanoparticles has been an area of significant interest because of their wide range of applications. In the present study, we have successfully synthesized water soluble silver nanoparticles assisted by small amino acid glycine. The method is primarily based on reduction of AgNO 3 with NaBH 4 in aqueous solution under atmospheric air in the presence of glycine. UV–vis spectroscopy, transmission electron microscopy (TEM), X–ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG) and differential thermal analysis (DTA) techniques used for characterization of resulting silver nanoparticles demonstrated that, glycine is an effective capping agent to stabilize silver nanoparticles. Surface selective interaction of glycine on (1 1 1) face of silver nanoparticles has been investigated. The optical property and crystalline behavior of silver nanoparticles were found to be sensitive to concentration of glycine. X–ray diffraction studies ascertained the phase specific interaction of glycine on silver nanoparticles. Silver nanoparticles synthesized were of diameter 60 nm. We thus demonstrated an efficient synthetic method for synthesis of water soluble silver nanoparticles capped by amino acid under mild reaction conditions with excellent reproducibility

  20. Spatial and temporal variability of water soluble carbon for a cropped field

    International Nuclear Information System (INIS)

    Liss, H.J.; Rolston, D.E.

    1983-01-01

    The water soluble carbon from soil extracts was taken from a two-hundred point grid established on a 1.2 ha field. The sampling was in the fall after the harvest of a sorghum crop. The concentrations ranged from 23.8 ppm to 274.2 ppm. Over 90 per cent of the concentrations were grouped around the mean of 40.3 ppm. The higher values caused the distribution to be greatly skewed such that neither normal nor log normal distributions characterized the data very well. The moisture content from the same samples followed normal distribution. Changes in the mean, the variance and the distribution of water soluble carbon were followed on 0.4 ha of the 1.2 ha in a grid of sixty points during a crop of wheat and a subsequent crop of sorghum. The mean increased in the spring, decreased in the summer and increased again in the fall. The spring and summer concentrations are well characterized by log normal distributions. The spatial dependence of water soluble carbon was examined on a fifty-five point transect across the field spaced every 1.37 m. The variogram indicated little or no dependence at this spacing. (author)

  1. Transpiration directly regulates the emissions of water-soluble short-chained OVOCs.

    Science.gov (United States)

    Rissanen, K; Hölttä, T; Bäck, J

    2018-04-20

    Most plant-based emissions of volatile organic compounds (VOCs) are considered mainly temperature dependent. However, certain oxygenated VOCs (OVOCs) have high water solubility; thus, also stomatal conductance could regulate their emissions from shoots. Due to their water solubility and sources in stem and roots, it has also been suggested that their emissions could be affected by transport in xylem sap. Yet, further understanding on the role of transport has been lacking until present. We used shoot-scale long-term dynamic flux data from Scots pines (Pinus sylvestris) to analyse the effects of transpiration and transport in xylem sap flow on emissions of three water soluble OVOC: methanol, acetone and acetaldehyde. We found a direct effect of transpiration on the shoot emissions of the three OVOCs. The emissions were best explained by a regression model that combined linear transpiration and exponential temperature effects. In addition, a structural equation model indicated that stomatal conductance affects emissions mainly indirectly, by regulating transpiration. A part of temperature's effect is also indirect. The tight coupling of shoot emissions to transpiration clearly evidences that these OVOCs are transported in xylem sap from their sources in roots and stem to leaves and to ambient air. This article is protected by copyright. All rights reserved.

  2. Abalone water-soluble matrix for self-healing biomineralization of tooth defects.

    Science.gov (United States)

    Wen, Zhenliang; Chen, Jingdi; Wang, Hailiang; Zhong, Shengnan; Hu, Yimin; Wang, Zhili; Zhang, Qiqing

    2016-10-01

    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53wt% the abalone water-soluble protein (AWSPro) and 2.04wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Phase equilibrium of (CO2 + 1-aminopropyl-3-methylimidazolium bromide + water) electrolyte system and effects of aqueous medium on CO2 solubility: Experiment and modeling

    International Nuclear Information System (INIS)

    Chen, Ying; Guo, Kaihua; Bi, Yin; Zhou, Lan

    2017-01-01

    Highlights: • Phase and chemical equilibrium data for (CO 2 + [APMIm]Br + H 2 O) electrolyte system. • A modified eNRTL model for CO 2 solubility in the amino-based IL aqueous solution. • Effects of aqueous medium on both chemical and physical dissolution of CO 2 . • The correlative coefficient, R s ∗ , for the Henry’s constant of the solution. • New parameters for the segments interaction and the chemical equilibrium constants. - Abstract: New experimental data for solubility of carbon dioxide (CO 2 ) in the aqueous solution of 1-aminopropyl-3-methylimidazolium bromide ([APMIm]Br) with four different water mass fractions (0.559, 0.645, 0.765 and 0.858) at T = (278.15–348.15) K with an interval of T = 10 K and p = (0.1237–6.9143) MPa were presented. The electrolyte nonrandom two-liquid (eNRTL) model was modified to be applicable for an ionic liquid (IL) aqueous solution system, by introducing an idle factor β to illustrate the association effect of IL molecules. A solution Henry’s constant for CO 2 solubility in the IL aqueous solution was defined by introducing a correlative coefficient R s ∗ . The vapor-liquid phase equilibrium of the [APMIm]Br-H 2 O-CO 2 ternary system was successfully calculated with the modified eNRTL model. The chemical and physical mechanisms for the ionized CO 2 formation and the molecular CO 2 dissolved in the solution were identified. The effects of aqueous medium on both chemical and physical dissolution of CO 2 in the [APMIm]Br aqueous solution were studied, and a considerable enhancement of the solubility of CO 2 with increase of the water content in the solution was observed.

  4. Neutronic studies of a liquid hydrogen-water composite moderator

    International Nuclear Information System (INIS)

    Tahara, T.; Ooi, M.; Iwasa, H.; Kiyanagi, Y.; Iverson, E.B.; Crabtree, J.A.; Lucas, A.T.

    2001-01-01

    A liquid hydrogen-liquid water composite moderator may provide performance like liquid methane at high-power spallation sources where liquid methane is impractical. We have measured the neutronic properties of such a composite moderator, where a hydrogen layer 1.25 cm thick was closely backed by water layers of 1.75 cm and 3.75 cm thickness. We also studied a moderator in which a 1.75 cm water layer was closely backed by a 1.25 cm hydrogen layer. We further performed simulations for each of these systems for comparison to the experimental results. We observed enhancement of the spectral intensity in the 'thermal' energy range as compared to the spectrum from a conventional liquid hydrogen moderator. This enhancement grew more significant as the water thickness increased, although the pulse shapes became wider as well. (author)

  5. Preparation of 'dead water' for low background liquid scintillation counting

    International Nuclear Information System (INIS)

    Morishima, Hiroshige; Koga, Taeko; Niwa, Takeo; Kawai, Hiroshi

    1987-01-01

    'Dead water', low level tritiated water is indispensable to measure tritium concentration in environmental waters using a low background liquid scintillation counter. Water produced by combustion of natural gas, or deep sea water etc. are usually used for the above purpose. A new method of reducing tritium concentration in natural water has been introduced for preparation of 'dead water'. This method is to combine hydrogen-oxygen mixture produced by water electrolysis with hopcalite catalyzer at 700 deg C. Deep well water was electrolized up to 2/3 volume, and tritium concentration of recombined water was reduced to be about one third of that of the original one. (author)

  6. Molecular dynamics study of salt–solution interface: Solubility and surface charge of salt in water

    International Nuclear Information System (INIS)

    Kobayashi, Kazuya; Liang, Yunfeng; Matsuoka, Toshifumi; Sakka, Tetsuo

    2014-01-01

    The NaCl salt–solution interface often serves as an example of an uncharged surface. However, recent laser-Doppler electrophoresis has shown some evidence that the NaCl crystal is positively charged in its saturated solution. Using molecular dynamics (MD) simulations, we have investigated the NaCl salt–solution interface system, and calculated the solubility of the salt using the direct method and free energy calculations, which are kinetic and thermodynamic approaches, respectively. The direct method calculation uses a salt–solution combined system. When the system is equilibrated, the concentration in the solution area is the solubility. In the free energy calculation, we separately calculate the chemical potential of NaCl in two systems, the solid and the solution, using thermodynamic integration with MD simulations. When the chemical potential of NaCl in the solution phase is equal to the chemical potential of the solid phase, the concentration of the solution system is the solubility. The advantage of using two different methods is that the computational methods can be mutually verified. We found that a relatively good estimate of the solubility of the system can be obtained through comparison of the two methods. Furthermore, we found using microsecond time-scale MD simulations that the positively charged NaCl surface was induced by a combination of a sodium-rich surface and the orientation of the interfacial water molecules

  7. Acid-base equilibria and solubility of loratadine and desloratadine in water and micellar media.

    Science.gov (United States)

    Popović, Gordana; Cakar, Mira; Agbaba, Danica

    2009-01-15

    Acid-base equilibria in homogeneous and heterogeneous systems of two antihistaminics, loratadine and desloratadine were studied spectrophotometrically in Britton-Robinson's buffer at 25 degrees C. Acidity constant of loratadine was found to be pK(a) 5.25 and those of desloratadine pK(a1) 4.41 and pK(a2) 9.97. The values of intrinsic solubilities of loratadine and desloratadine were 8.65x10(-6) M and 3.82x10(-4) M, respectively. Based on the pK(a) values and intrinsic solubilities, solubility curves of these two drugs as a function of pH were calculated. The effects of anionic, cationic and non-ionic surfactants applied in the concentration exceeding critical micelle concentration (cmc) on acid-base properties of loratadine and desloratadine, as well as on intrinsic solubility of loratadine were also examined. The results revealed a shift of pK(a) values in micellar media comparing to the values obtained in water. These shifts (DeltapK(a)) ranged from -2.24 to +1.24.

  8. Solubility of oxygen in liquid sodium: effect on interpretation of corrosion data

    International Nuclear Information System (INIS)

    Claxton, K.T.

    1976-01-01

    No solubility correlation relating the equilibrium oxygen concentration with the sodium saturation temperature has yet been derived which has gained general acceptance. A statistical analysis of all the available data which directly or indirectly may be taken as representing a measurement of solubility has been made. The results indicate that a real and seemingly permanent difference is apparent between the assumed equilibrium levels of oxygen measured at different saturation temperatures as reported by UK and US workers. Data analysis procedures producing sub-sets of culled data which are then used to derive a compromise solubility function are considered less than adequate. It is considered preferable and more realistic to distinguish data sub-sets by the analytical technique employed. The established vacuum distillation method is shown to yield results differing among themselves by up to a factor of four at cold trap temperatures of relevance to fast reactor operation. The vanadium wire and electrochemical cell techniques are shown to give the lowest solubility values. Appropriate factors relating UK oxygen levels to values derived from alternative methods are presented. The divergent positions prevailing for oxygen-in-sodium analysis can lead to apparent anomalies when comparisons of corrosion rates from different sources have to be made. It is shown that this situation is, in part, apparently resolved by effecting comparisons at the equivalent cold trap temperature instead of the equivalent oxygen level. It is recognised that the approach presumes equilibrium of the oxygen in the sodium with the cold trap and reference is made to alternative ''sinks'' for oxygen. It is demonstrated, by comparison of a number of recommended and observed corrosion rates from US and European sources, that, in spite of the above and other qualifications, the approach is reasonable

  9. Extractive behavior of U(VI) in the paraffin soluble ionic liquid

    International Nuclear Information System (INIS)

    Rama, R.; Kumaresan, R.; Venkatesan, K.A.; Antony, M.P.; Vasudeva Rao, P.R.

    2013-01-01

    An Aliquat-336 based ionic liquid namely, tri-n-octylmethylammonium bis(2-ethylhexyl)phosphate ((A3636) + (DEHP) - ) was prepared and studied for the extraction of U(VI) from nitric acid medium. Since the ionic liquid, (A336) + (DEHP) - , was miscible in n-dodecane (n-DD), the extraction of U(VI) in the solution of tri-n-butylphosphate (TBP) in n-DD, was investigated in the presence of small concentrations of ionic liquid. The distribution ratio of U(VI) in 0.3 M (A336) + (DEHP) - /n-DD decreased with increase in the concentration of nitric acid. The effect of concentration of TBP, ionic liquid nitric acid and nitrate ion on the extraction of U(VI) in ionic liquid medium was studied. The mechanistic aspect of extraction was investigated by the slope analysis of the extraction data. The studies indicated the feasibility of modifying the extractive properties of U(VI) in TBP/n-DD using ionic liquid. (author)

  10. Improved Bilayer Resist System Using Contrast-Enhanced Lithography With Water-Soluble Photopolymer

    Science.gov (United States)

    Sasago, Masaru; Endo, Masayuki; Hirai, Yoshihiko; Ogawa, Kazufurni; Ishihara, Takeshi

    1986-07-01

    A new water-soluble contract enhanced material, WSP (Water-soluble Photopolymer), has been developed. The WSP is composed of a mainpolymer and a photobleachable reagents. The mainpolymer is a water-soluble polymer mixed with pullulan (refined through biotechnological process) and polyvinyl-pyrolidone (PVP). The photo-bleachable reagent is of a diazonium compound gorup. The introduction of the mainpolymer and photobleach-able reagent mixture has improved filmity, gas transparency, photobleaching characteristics and solubility in alkaline which are essential to the device fabrication. Submicron photoresist patterns are successfully fabricated by a simple sequence of photolithography process. The WSP layer has been applied to the bilayer resist system--deep-UV portable conformable masking (PCM)--that is not affected by VLSI's topography, and is able to fabricate highly accurate pattern. The aqueous developable layer, PMGI, with high organic solvent resistance is used in the bottom layer. Therefore, no interfacial mixing with conventional positive resist top layer is observed. Furthermore, deep-UV exposure method has been used for the KrF excimer laser optical system in order to increase high throughput. From the experiments, it has been confirmed that good resist transfer profile can be realized by the use of WSP, and that the submicron resist patterns with high aspect-ratio can be developed on the nonplaner wafer with steps of up to 41m by the combination of the WSP with the PCM system. By this technology, has been improved the weak point: variation in the line width due to the thickness of contrast-enhanced layer when the CEL technology is applied, and dependency of both the finished resist profile and the line-width accuracy on the thickness of the top layer resist when the PCM system is adopted.

  11. In vitro and in vivo antioxidant activity of a water-soluble polysaccharide from dendrobium denneanum

    Science.gov (United States)

    Luo, A.; Ge, Z.; Fan, Y.; Chun, Z.; Jin, He X.

    2011-01-01

    The water-soluble crude polysaccharide (DDP) obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant. ?? 2011.

  12. In Vitro and In Vivo Antioxidant Activity of a Water-Soluble Polysaccharide from Dendrobium denneanum

    Directory of Open Access Journals (Sweden)

    XingJin He

    2011-02-01

    Full Text Available The water-soluble crude polysaccharide (DDP obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw of about  484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant.

  13. Preliminary experimental study of liquid lithium water interaction

    International Nuclear Information System (INIS)

    You, X.M.; Tong, L.L.; Cao, X.W.

    2015-01-01

    Highlights: • Explosive reaction occurs when lithium temperature is over 300 °C. • The violence of liquid lithium water interaction increases with the initial temperature of liquid lithium. • The interaction is suppressed when the initial water temperature is above 70 °C. • Steam explosion is not ignorable in the risk assessment of liquid lithium water interaction. • Explosion strength of liquid lithium water interaction is evaluated by explosive yield. - Abstract: Liquid lithium is the best candidate for a material with low Z and low activation, and is one of the important choices for plasma facing materials in magnetic fusion devices. However, liquid lithium reacts violently with water under the conditions of loss of coolant accidents. The release of large heats and hydrogen could result in the dramatic increase of temperature and pressure. The lithium–water explosion has large effect on the safety of fusion devices, which is an important content for the safety assessment of fusion devices. As a preliminary investigation of liquid lithium water interaction, the test facility has been built and experiments have been conducted under different conditions. The initial temperature of lithium droplet ranged from 200 °C to 600 °C and water temperature was varied between 20 °C and 90 °C. Lithium droplets were released into the test section with excess water. The shape of lithium droplet and steam generated around the lithium were observed by the high speed camera. At the same time, the pressure and temperature in the test section were recorded during the violent interactions. The preliminary experimental results indicate that the initial temperature of lithium and water has an effect on the violence of liquid lithium water interaction.

  14. Preliminary experimental study of liquid lithium water interaction

    Energy Technology Data Exchange (ETDEWEB)

    You, X.M.; Tong, L.L.; Cao, X.W., E-mail: caoxuewu@sjtu.edu.cn

    2015-10-15

    Highlights: • Explosive reaction occurs when lithium temperature is over 300 °C. • The violence of liquid lithium water interaction increases with the initial temperature of liquid lithium. • The interaction is suppressed when the initial water temperature is above 70 °C. • Steam explosion is not ignorable in the risk assessment of liquid lithium water interaction. • Explosion strength of liquid lithium water interaction is evaluated by explosive yield. - Abstract: Liquid lithium is the best candidate for a material with low Z and low activation, and is one of the important choices for plasma facing materials in magnetic fusion devices. However, liquid lithium reacts violently with water under the conditions of loss of coolant accidents. The release of large heats and hydrogen could result in the dramatic increase of temperature and pressure. The lithium–water explosion has large effect on the safety of fusion devices, which is an important content for the safety assessment of fusion devices. As a preliminary investigation of liquid lithium water interaction, the test facility has been built and experiments have been conducted under different conditions. The initial temperature of lithium droplet ranged from 200 °C to 600 °C and water temperature was varied between 20 °C and 90 °C. Lithium droplets were released into the test section with excess water. The shape of lithium droplet and steam generated around the lithium were observed by the high speed camera. At the same time, the pressure and temperature in the test section were recorded during the violent interactions. The preliminary experimental results indicate that the initial temperature of lithium and water has an effect on the violence of liquid lithium water interaction.

  15. Experimental evidence of a liquid-liquid transition in interfacial water

    Science.gov (United States)

    Zanotti, J.-M.; Bellissent-Funel, M.-C.; Chen, S.-H.

    2005-07-01

    At ambient pressure, bulk liquid water shows an anomalous increase of thermodynamic quantities and apparent divergences of dynamic properties on approaching a temperature Ts of 228 K. At normal pressure, supercooled water spontaneously freezes below the homogeneous nucleation temperature, TH = 235 K. Upon heating, the two forms of Amorphous Solid Water (ASW), LDA (Low Density Amorphous Ice) and HDA (High Density Amorphous Ice), crystallise above TX = 150 K. As a consequence, up to now no experiment has been able to explore the properties of liquid water in this very interesting temperature range between 150 and 235 K. We present nanosecond-time-scale measurements of local rotational and translational dynamics of interfacial, non-crystalline, water from 77 to 280 K. These experimental dynamic results are combined with calorimetric and diffraction data to show that after exhibiting a glass transition at 165 K, interfacial water experiences a first-order liquid-liquid transition at 240 K from a low-density to a high-density liquid. This is the first direct evidence of the existence of a liquid-liquid transition involving water.

  16. 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.

  17. 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

  18. Heat transfer on liquid-liquid interface of molten-metal and water

    International Nuclear Information System (INIS)

    Tanaka, T.; Saito, Yasushi; Mishima, Kaichiro

    2001-01-01

    Molten-core pool had been formed in the lower-head of TMI-2 pressure vessel at the severe accident. The lower head, however, didn't receive any damage by reactor core cooling. Heat transfer at outside of the lower head and boiling heat transfer at liquid-liquid interface of molten-metal and water, however, are important for initial cooling process of the molten-core pool. The heat transfer experiments for the liquid-liquid interface of molten-metal and water are carried out over the range of natural convection to film boiling region. Phenomenon on the heat transfer experiments are visualized by using of high speed video camera. Wood's metal and U-alloy 78 are used as molten-metal. The test section of the experiments consists of a copper block with heater, wood's metal, and water. Three thermocouple probes are used for temperature measurement of water side and the molten-metal side. Stability of the liquid-liquid interface is depended on the wetness of container wall for molten metal and the temperature distribution of the interface. Entrainment phenomena of molten-metal occurs by a fluctuation of the interface after boiling on the container wall surface. The boiling curves obtained from the liquid-liquid interface experiments are agree with the nucleate boiling and the film boiling correlations of solid-liquid system. (Suetake, M.)

  19. Pentosan-derived water-soluble carbon nano dots with substantial fluorescence: Properties and application as a photosensitizer

    Science.gov (United States)

    Wu, Qiong; Li, Wei; Wu, Yanjiao; Huang, Zhanhua; Liu, Shouxin

    2014-10-01

    The hydrothermal carbonization of monosaccharides and polysaccharides is widely used in the production of carbonaceous material with a desired structure. However, the liquid products are regarded as waste and discarded. Here, we report a facile approach for the synthesis of water-soluble carbon nano dots (CNDs) with substantial fluorescence from the liquid by-products of the hydrothermal carbonization of pentosan, thus the by-products of pulp refining. The synthesized CNDs are monodispersed spheres with abundant oxygen-containing groups and they have an average size of 30 nm. Quantum yield measurements revealed CNDs with substantial green photoluminescence (PL) without passivation. Additionally, excitation was independent, pH-sensitive and stable. The use of CNDs as a photosensitizer in the CNDs/TiO2 system for methylene blue (MB) degradation under visible light irradiation is attractive. The spectral response range of the CNDs/TiO2 system can be widened from the UV region to a part of the visible light region (400-550 nm).

  20. Water-soluble chelating polymers for removal of actinides from wastewater

    International Nuclear Information System (INIS)

    Jarvinen, G.D.

    1997-01-01

    Polymer filtration is a technology under development to selectively recover valuable or regulated metal ions from process or wastewaters. The technology uses water-soluble chelating polymers that are designed to selectively bind with metal ions in aqueous solutions. The polymers have a sufficiently large molecular weight that they can be separated and concentrated using available ultrafiltration (UF) technology. The UF range is generally considered to include molecular weights from about 3000 to several million daltons and particles sizes of about 2 to 1000 nm. Water and smaller unbound components of the solution pass freely through the UF membrane. The polymers can then be reused by changing the solution conditions to release the metal ions that are recovered in concentrated form for recycle or disposal. Some of the advantages of polymer filtration relative to technology now in use are rapid binding kinetics, high selectivity, low energy and capital costs, and a small equipment footprint. Some potential commercial applications include electroplating rinse waters, photographic processing, nuclear power plant cooling water; remediation of contaminated soils and groundwater; removal of mercury contamination; and textile, paint and dye production. The purpose of this project is to evaluate this technology to remove plutonium, americium, and other regulated metal ions from various process and waste streams found in nuclear facilities. The work involves preparation of the water-soluble chelating polymers; small-scale testing of the chelating polymer systems for the required solubility, UF properties, selectivity and binding constants; followed by an engineering assessment at a larger scale to allow comparison to competing separation technologies. This project focuses on metal-ion contaminants in waste streams at the Plutonium Facility and the Waste Treatment Facility at LANL. Potential applications at other DOE facilities are also apparent

  1. Water-soluble chelating polymers for removal of actinides from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Jarvinen, G.D. [Los Alamos National Lab., NM (United States)

    1997-10-01

    Polymer filtration is a technology under development to selectively recover valuable or regulated metal ions from process or wastewaters. The technology uses water-soluble chelating polymers that are designed to selectively bind with metal ions in aqueous solutions. The polymers have a sufficiently large molecular weight that they can be separated and concentrated using available ultrafiltration (UF) technology. The UF range is generally considered to include molecular weights from about 3000 to several million daltons and particles sizes of about 2 to 1000 nm. Water and smaller unbound components of the solution pass freely through the UF membrane. The polymers can then be reused by changing the solution conditions to release the metal ions that are recovered in concentrated form for recycle or disposal. Some of the advantages of polymer filtration relative to technology now in use are rapid binding kinetics, high selectivity, low energy and capital costs, and a small equipment footprint. Some potential commercial applications include electroplating rinse waters, photographic processing, nuclear power plant cooling water; remediation of contaminated soils and groundwater; removal of mercury contamination; and textile, paint and dye production. The purpose of this project is to evaluate this technology to remove plutonium, americium, and other regulated metal ions from various process and waste streams found in nuclear facilities. The work involves preparation of the water-soluble chelating polymers; small-scale testing of the chelating polymer systems for the required solubility, UF properties, selectivity and binding constants; followed by an engineering assessment at a larger scale to allow comparison to competing separation technologies. This project focuses on metal-ion contaminants in waste streams at the Plutonium Facility and the Waste Treatment Facility at LANL. Potential applications at other DOE facilities are also apparent.

  2. Solubility of mixed monomers of tetrafluoroethylene and propylene in water and latex

    International Nuclear Information System (INIS)

    Watanabe, Hiromasa; Okamoto, Jiro

    1978-03-01

    For kinetical analysis of the emulsion copolymerization of tetrafluoroethylene with propylene and selection of the optimum reaction conditions, the monomer concentrations and composition of the polymer particle were measured and the relations with reaction conditions were determined. Solubilities of tetrafluoroethylene and propylene in water increase with pressure. solubility of propylene is larger than that of tetrafluoroethylene. Solubility of the mixed monomers in water and latex increases with pressure and propylene concentration and decreases with temperature. Propylene concentration in the dissolved monomers is dependent on its concentration in the gas phase and independent of pressure and temperature. The monomer concentrations and the composition were estimated from measurements. Under propylene concentration in the gas phase of 0 to 40 wt % at 30 Kg/cm 2 G and 40 0 C, the monomer concentration and propylene fraction of the polymer particle are 17 -- 27% and 0 -- 62% respectively. The amount of propylene in the particle increases with its fraction in the gas phase, but the amount of tetrafluoroethylene is independent of its fraction in the gas phase. Monomer composition of the polymer particle is dependent on monomer composition of the gas phase and independent of temperature and pressure. The concentration in the polymer particle is 17% at propylene concentration 10 mole % in the gas phase. (auth.)

  3. Highly water-soluble, porous, and biocompatible boron nitrides for anticancer drug delivery.

    Science.gov (United States)

    Weng, Qunhong; Wang, Binju; Wang, Xuebin; Hanagata, Nobutaka; Li, Xia; Liu, Dequan; Wang, Xi; Jiang, Xiangfen; Bando, Yoshio; Golberg, Dmitri

    2014-06-24

    Developing materials for "Nano-vehicles" with clinically approved drugs encapsulated is envisaged to enhance drug therapeutic effects and reduce the adverse effects. However, design and preparation of the biomaterials that are porous, nontoxic, soluble, and stable in physiological solutions and could be easily functionalized for effective drug deliveries are still challenging. Here, we report an original and simple thermal substitution method to fabricate perfectly water-soluble and porous boron nitride (BN) materials featuring unprecedentedly high hydroxylation degrees. These hydroxylated BNs are biocompatible and can effectively load anticancer drugs (e.g., doxorubicin, DOX) up to contents three times exceeding their own weight. The same or even fewer drugs that are loaded on such BN carriers exhibit much higher potency for reducing the viability of LNCaP cancer cells than free drugs.

  4. Thermodynamic interactions of water-soluble homopolymers and double-hydrophilic diblock copolymer

    International Nuclear Information System (INIS)

    Yazici, D. Topaloglu; Askin, A.; Buetuen, V.

    2008-01-01

    Thermodynamic interaction parameters of water-soluble poly[2-(dimethylamino)ethyl methacrylate] (DMA) and poly[2-(N-morpholino)ethyl methacrylate] (MEMA) homopolymers and their diblock copolymer (DMA-MEMA) were investigated at the temperatures above their glass-transition temperatures (T g ) by inverse gas chromatography (IGC) method. Sorption thermodynamic parameters of some aliphatic, alicyclic and aromatic hydrocarbons, weight fraction activity coefficients, Flory-Huggins interaction parameters, and solubility parameters for hydrocarbons and polymers were calculated. It was observed that sorption thermodynamic parameters on (co)polymers depend on the molecular structures of hydrocarbons. Evaluating both the calculated values of the weight fraction activity coefficients and Flory-Huggins interaction parameters, the solving ability of the hydrocarbons for DMA, MEMA homopolymers, and DMA-MEMA diblock copolymer decreased in the following sequence: Aromatic > alicyclic > aliphatic hydrocarbons

  5. Aryl-derivatized, water-soluble functionalized carbon nanotubes for biomedical applications

    International Nuclear Information System (INIS)

    Karousis, N.; Ali-Boucetta, H.; Kostarelos, K.; Tagmatarchis, N.

    2008-01-01

    The functionalization of very-thin multi-walled carbon nanotubes (VT-MWNTs) with an aniline derivative, via the protocol of in situ generated aryl diazonium salts results, upon acidic deprotection of the terminal BOC group, on the formation of the water-soluble positively charged ammonium functionalized VT-MWNTs-NH 3 + material. The new materials have been structurally and morphologically characterized by infra-red (ATR-IR) spectroscopy and transmission electron microscopy (TEM). The quantitative calculation of the grafted aryl units onto the skeleton of VT-MWNTs has been estimated by thermogravimetric analysis (TGA), while the quantitative Kaiser test showed the amine group loaded onto VT-MWNTs-NH 3 + material. The aqueous solubility of this material has allowed the performance of some initial toxicological in vitro investigations

  6. Synthesis, structure, antioxidant activity, and water solubility of trolox ion conjugates

    Directory of Open Access Journals (Sweden)

    Yuliya V. Yushkova

    2018-01-01

    Full Text Available The interaction of trolox with ammonia, alkylamines of different classes, and amino derivatives of heterocyclic compounds, including nitroxyl radicals and alkaloids, led to the production of ammonium salts called ion conjugates (ICs. Five ICs were characterised by X-ray diffraction. This is the first time a wide range of ICs were made from trolox with amines, and ESI-MS data demonstrated they have the potential to generate pseudomolecular [(A−B+ + H]+ ions. For all obtained trolox ICs, a significant increase (1–3 orders of magnitude in water solubility was achieved while retaining high antioxidant activity. ICs synthesised from two biologically active fragments may be used to create polyfunctional agents with varying solubility and bioavailability. Keywords: Trolox, Amines, Ion conjugates, Antioxidants, Mass-spectrometry

  7. Determination of fat- and water-soluble vitamins by supercritical fluid chromatography: A review.

    Science.gov (United States)

    Tyśkiewicz, Katarzyna; Dębczak, Agnieszka; Gieysztor, Roman; Szymczak, Tomasz; Rój, Edward

    2018-01-01

    Vitamins are compounds that take part in all basic functions of an organism but also are subject of number of studies performed by different researchers. Two groups of vitamins are distinguished taking into consideration their solubility. Chromatography with supercritical CO 2 has found application in the determination, separation, and quantitative analyses of both fat- and water-soluble vitamins. The methods of vitamins separation have developed and improved throughout the years. Both groups of compounds were separated using supercritical fluid chromatography with different detection on different stationary phases. The main aim of this review is to provide an overview of the studies of vitamins separation that have been determined so far. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Characterization of soluble microbial products as precursors of disinfection byproducts in drinking water supply.

    Science.gov (United States)

    Liu, Jin-Lin; Li, Xiao-Yan; Xie, Yue-Feng; Tang, Hao

    2014-02-15

    Water pollution by wastewater discharge can cause the problem of disinfection byproducts (DBPs) in drinking water supply. In this study, DBP formation characteristics of soluble microbial products (SMPs) as the main products of wastewater organic biodegradation were investigated. The results show that SMPs can act as DBP precursors in simulated wastewater biodegradation process. Under the experimental conditions, stabilized SMPs had DBPFP (DBP formation potential) yield of around 5.6 μmol mmol(-1)-DOC (dissolved organic carbon) and DBP speciation profile different from that of the conventional precursor, natural organic matter (NOM). SMPs contained polysaccharides, proteins, and humic-like substances, and the latter two groups can act as reactive DBP precursors. SMP fraction with molecular weight of water treatment processes, more efforts are needed to control wastewater-derived DBP problem in water resource management. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Further evidence of a liquid-liquid transition in interfacial water

    International Nuclear Information System (INIS)

    Zanotti, J-M; Bellissent-Funel, M C; Chen, S-H; Kolesnikov, A I

    2006-01-01

    In a previous paper we combined calorimetric, diffraction and high-resolution quasi-elastic neutron scattering data to show that after exhibiting a glass transition at 165 K, interfacial water experiences a first order liquid-liquid transition at 240 K from a low-density to a high-density liquid. Here we present further evidence of these transitions obtained by high-energy inelastic neutron scattering

  10. Deuterium exchange between liquid water and gaseous hydrogen

    International Nuclear Information System (INIS)

    Dave, S.M.; Ghosh, S.K.; Sadhukhan, H.K.

    1982-01-01

    The overall separation factors for the deuterium exchange between liquid water and gaseous hydrogen have been calculated over a wide range of temperature, pressure and deuterium concentrations. These data would be useful in the design and other considerations for heavy water production, based on hydrogen-water exchange. (author)

  11. Effect of Bombay high crude oil and its water-soluble fraction on growth and metabolism of diatom Thalassiosira sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Parab, S.R.; Pandit, R.A.; Kadam, A.N.; Indap, M.M.

    Effect of Bombay high crude oil (BHC) and its water-soluble fraction (WSF) on growth and metabolism of the phytoplankton, Thalassiosira sp. was assessed. The study revealed the signs of acute toxicity at higher concentrations of crude oil (0...

  12. Water at silica/liquid water interfaces investigated by DFT-MD simulations

    Science.gov (United States)

    Gaigeot, Marie-Pierre

    This talk is dedicated to probing the microscopic structural organization of water at silica/liquid water interfaces including electrolytes by first principles DFT-based molecular dynamics simulations (DFT-MD). We will present our very recent DFT-MD simulations of electrolytic (KCl, NaCl, NaI) silica/liquid water interfaces in order to unravel the intertwined structural properties of water and electrolytes at the crystalline quartz/liquid water and amorphous silica/liquid water interfaces. DFT-MD simulations provide direct knowledge of the structural organization of water and the H-Bond network formed between the water molecules within the different water layers above the silica surface. One can furthermore extract vibrational signatures of the water molecules within the interfacial layers from the DFT-MD simulations, especially non-linear SFG (Sum Frequency generation) signatures that are active at solid/liquid interfaces. The strength of the simulated spectra is that a detailed analysis of the signatures in terms of the water/water H-Bond networks formed within the interfacial water layers and in terms of the water/silica or water/electrolytes H-Bond networks can be given. Comparisons of SFG spectra between quartz/water/electrolytes and amorphous silica/water/electrolytes interfaces allow us to definitely conclude on how the structural arrangements of liquid water at these electrolytic interfaces modulate the final spectroscopic signatures. Invited speaker.

  13. Selective hydrogenation of 1,3-butadiene from crude C{sub 4} cracker stream with a solid catalyst with ionic liquid layer (SCILL). DSC and solubility study

    Energy Technology Data Exchange (ETDEWEB)

    Mangartz, T.; Korth, W.; Kern, C.; Jess, A. [Bayreuth Univ. (Germany). Dept. of Chemical Engineering

    2013-11-01

    In petroleum as well as in fine chemical industry, selective catalytic hydrogenation is an important reaction. The selective hydrogenation of 1,3-butadiene (BD) to butene (trans-,1- and cis-butene) from the crude C4 steam cracker fraction represents one example, but under today's technical conditions undesired butane forms inevitably in relevant amounts. To increase the butene yield, the concept of Solid Catalyst with Ionic Liquid Layer (SCILL) was employed. The SCILL catalyst, in contrast to the uncoated catalyst, yielded a remarkably high selectivity to butenes (S{sub butenes} > 99 %) even at high residence times or at high hydrogen partial pressure. Nearly no butane (S{sub butane} {approx} 0 %) was analytically detected. We expected that due to different solubility, the poorer soluble compounds discharged from the ionic liquid and, thus, caused the shift in selectivity to a great extent. Temperature dependent solubility measurements in the used ionic liquid ([DMIM][DMP]) revealed that the order of increasing solubility is 1,3-butadiene > butenes > butane which matches the assumption. However, since differences in solubility cannot explain this SCILL effect satisfyingly, ionic liquids are expected to affect the surface of the catalyst (side-specific ligand-type effect). Investigations using spectroscopic methods (e.g. FTIR) confirmed this suggestion. (orig.)

  14. (Liquid + liquid) equilibria for (water + 1-propanol or acetone + β-citronellol) at different temperatures

    International Nuclear Information System (INIS)

    Li, Hengde; Han, Yongtao; Huang, Cheng; Yang, Chufen

    2015-01-01

    Graphical abstract: (Liquid + liquid) equilibrium data for systems composed of β-citronellol and aqueous 1-propanol or acetone are presented. Distribution ratios of 1-propanol and acetone in the mixtures are examined. The effect of the temperature on the ternary (liquid + liquid) equilibria is evaluated and discussed. - Highlights: • Ternary (liquid + liquid) equilibria containing β-citronellol are presented. • Distribution ratios of 1-propanol and acetone in the mixtures are examined. • The effect on the temperature of the systems is evaluated and discussed. - Abstract: On this paper, experimental (liquid + liquid) equilibrium (LLE) results are presented for systems composed of β-citronellol and aqueous 1-propanol or acetone. To evaluate the phase separation properties of β-citronellol in aqueous mixtures, LLE values for the ternary systems (water + 1-propanol + β-citronellol) and (water + acetone + β-citronellol) were determined with a tie-line method at T = (283.15, 298.15, and 313.15 ± 0.02) K and atmospheric pressure. The reliability of the experimental tie-lines was verified by the Hand and Bachman equations. Ternary phase diagrams, distribution ratios of 1-propanol and acetone in the mixtures are shown. The effect of the temperature on the ternary (liquid + liquid) equilibria was examined and discussed. The experimental LLE values were satisfactorily correlated by extended UNIQUAC and modified UNIQUAC models

  15. Application of liquid chromatography techniques to the measurement of soluble transition metals in PWR primary coolant

    International Nuclear Information System (INIS)

    Amey, M.D.H.; Brown, G.R.

    1987-01-01

    Two chromatographic techniques have been developed, and evaluated for the on-line analysis of soluble transition metals, particularly cobalt, in PWR primary coolant. Automatic operation and control, together with data processing and storage has been achieved by interfacing a Dionex ion chromatograph to a microprocessor control system. An absolute detection limit of 0.1 ng cobalt has been obtained which, with on-line sample preconcentration (100 ml), has enabled measurements to be made down to part-per-trillion levels (0.001 ppb). Application of the techniques to PWR coolant analysis was demonstrated by a programme of work on the Half Megawatt Loop at Winfrith. During this work some aspects of the behaviour of soluble metal species have been studied in both de-oxygenated and hydrogenated conditions. The effects of changes in coolant chemistry, operating temperature, and sample line flowrates on circulating impurity levels are reported, together with the dramatic effects observed when part of the circuit pipework was replaced with new stainless steel tubing. (author)

  16. Droplet-Sizing Liquid Water Content Sensor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Icing is one of the most significant hazards to aircraft. A sizing supercooled liquid water content (SSLWC) sonde is being developed to meet a directly related need...

  17. Water-Soluble N-Heterocyclic Carbene-Protected Gold Nanoparticles: Size-Controlled Synthesis, Stability, and Optical Properties

    OpenAIRE

    Salorinne, Kirsi; Man, Renee W.Y.; Li, Chien-Hung; Taki, Masayasu; Nambo, Masakazu; Crudden, Cathleen M.

    2017-01-01

    NHC-Au(I) complexes were used to prepare stable, water-soluble, NHC-protected gold nanoparticles. The water-soluble, charged nature of the nanoparticles permitted analysis by polyacrylamide gel electrophoresis (PAGE), which showed that the nanoparticles were highly monodisperse, with tunable core diameters between 2.0 and 3.3 nm depending on the synthesis conditions. Temporal, thermal, and chemical stability of the nanoparticles were determined to be high. Treatment with thiols caused etching...

  18. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    Science.gov (United States)

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory.

  19. Novel catalysts for isotopic exchange between hydrogen and liquid water

    International Nuclear Information System (INIS)

    Butler, J.P.; Rolston, J.H.; Stevens, W.H.

    1978-01-01

    Catalytic isotopic exchange between hydrogen and liquid water offers many inherent potential advantages for the separation of hydrogen isotopes which is of great importance in the Canadian nuclear program. Active catalysts for isotopic exchange between hydrogen and water vapor have long been available, but these catalysts are essentially inactive in the presence of liquid water. New, water-repellent platinum catalysts have been prepared by: (1) treating supported catalysts with silicone, (2) depositing platinum on inherently hydrophobic polymeric supports, and (3) treating platinized carbon with Teflon and bonding to a carrier. The activity of these catalysts for isotopic exchange between countercurrent streams of liquid water and hydrogen saturated with water vapor has been measured in a packed trickle bed integral reactor. The performance of these hydrophobic catalysts is compared with nonwetproofed catalysts. The mechanism of the overall exchange reaction is briefly discussed. 6 figures

  20. Simultaneous and accurate determination of water- and fat-soluble vitamins in multivitamin tablets by using an RP-HPLC method

    Directory of Open Access Journals (Sweden)

    Semahat Kucukkolbasi

    2013-01-01

    Full Text Available In the present study, a reversed-phase high-performance liquid chromatographic (RP-HPLC procedure was developed and validated for the simultaneous determination of seven water-soluble vitamins (thiamine, riboflavin, niacin, cyanocobalamin, ascorbic acid, folic acid, and p-aminobenzoic acid and four fat-soluble vitamins (retinol acetate, cholecalciferol, α-tocopherol, and phytonadione in multivitamin tablets. The linearity of the method was excellent (R² > 0.999 over the concentration range of 10 - 500 ng mL-1. The statistical evaluation of the method was carried out by performing the intra- and inter-day precision. The accuracy of the method was tested by measuring the average recovery; values ranged between 87.4% and 98.5% and were acceptable quantitative results that corresponded with the label claims.