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Sample records for acid insoluble material

  1. Conversion and Extraction of Insoluble Organic Materials in Meteorites

    NASA Technical Reports Server (NTRS)

    Locke, Darren R.; Burton, Aaron S.; Niles, Paul B.

    2016-01-01

    We endeavor to develop and implement methods in our laboratory to convert and extract insoluble organic materials (IOM) from low car-bon bearing meteorites (such as ordinary chondrites) and Precambrian terrestrial rocks for the purpose of determining IOM structure and prebiotic chemistries preserved in these types of samples. The general scheme of converting and extracting IOM in samples is summarized in Figure 1. First, powdered samples are solvent extracted in a micro-Soxhlet apparatus multiple times using solvents ranging from non-polar to polar (hexane - non-polar, dichloromethane - non-polar to polar, methanol - polar protic, and acetonitrile - polar aprotic). Second, solid residue from solvent extractions is processed using strong acids, hydrochloric and hydrofluoric, to dissolve minerals and isolate IOM. Third, the isolated IOM is subjected to both thermal (pyrolysis) and chemical (oxidation) degradation to release compounds from the macromolecular material. Finally, products from oxidation and pyrolysis are analyzed by gas chromatography - mass spectrometry (GCMS). We are working toward an integrated method and analysis scheme that will allow us to determine prebiotic chemistries in ordinary chondrites and Precambrian terrestrial rocks. Powerful techniques that we are including are stepwise, flash, and gradual pyrolysis and ruthenium tetroxide oxidation. More details of the integrated scheme will be presented.

  2. Insoluble organic material of the Orgueil carbonaceous chondrite and the unidentified infrared bands

    NASA Astrophysics Data System (ADS)

    Wdowiak, T. J.; Flickinger, G. C.; Cronin, J. R.

    1988-05-01

    Infrared spectra have been obtained of the acid insoluble residue, residue after heating in vacuum, and condensate of the Orgueil carbonaceous chondrite using an FTIR spectrometer. Bulk acid insoluble residue was pressed into KBr pellets and also heated under high vacuum to sublimate a volatile component onto KBr disks. The remaining nonvolatile organic component of the meteorite from such evaporations pressed into KBr pellets exhibits a spectral signature similar to that observed in emission from the Orion Nebula and found in Raman spectra of interplanetary dust particles. It also has an 11.3 micron band indicating polycyclic aromatic hydrocarbons (PAHs) having single hydrogens per peripheral aromatic ring. It is concluded that the nonvolatile material is similar to interstellar PAHs since the observed 11.3 micron unidentified infrared emission suggests interstellar PAHs have single hydrogens per peripheral aromatic ring.

  3. XPS and STEM studies of Allende acid insoluble residues

    NASA Technical Reports Server (NTRS)

    Housley, R. M.; Clarke, D. R.

    1980-01-01

    Data on Allende acid residues obtained both before and after etching with hot HNO3 are presented. X-ray photoelectron spectra show predominantly carbonaceous material plus Fe-deficient chromite in both cases. The HNO3 oxidizes the carbonaceous material to some extent. The small chromites in these residues have a wide range of compositions somewhat paralleling those observed in larger Allende chromites and in Murchison chromites, especially in the high Al contents; however, they are deficient in divalent cations, which makes them metastable and indicates that they must have formed at relatively low temperatures. It is suggested that they formed by precipitation of Cr(3+) and Fe(3+) from olivine at low temperature or during rapid cooling.

  4. Hydroxylamine hydrochloride-acetic acid-soluble and -insoluble fractions of pelagic sediment: Readsorption revisited

    USGS Publications Warehouse

    Piper, D.Z.; Wandless, G.A.

    1992-01-01

    The extraction of the rare earth elements (REE) from deep-ocean pelagic sediment, using hydroxylamine hydrochloride-acetic acid, leads to the separation of approximately 70% of the bulk REE content into the soluble fraction and 30% into the insoluble fraction. The REE pattern of the soluble fraction, i.e., the content of REE normalized to average shale on an element-by-element basis and plotted against atomic number, resembles the pattern for seawater, whereas the pattern, as well as the absolute concentrations, in the insoluble fraction resembles the North American shale composite. These results preclude significant readsorption of the REE by the insoluble phases during the leaching procedure.

  5. Study of insoluble crystals derived from solutions of Kevlar 49 in sulfuric acid

    SciTech Connect

    Butler, N.L.

    1984-05-21

    The object of the study was to isolate and obtain x-ray diffraction analysis of the insoluble crystals which have been observed in Kevlar 49/H/sub 2/SO/sub 4/ dope. These insoluble crystals had previously been reported to be Kevlar single crystals after analysis by optical microscopy. A more detailed analysis does not support this conclusion. Additional optical microscopy coupled with FTIR and elemental analysis for C, H and N, has shown that these insoluble crystals are in fact terephthalic acid which is a decomposition product of the acid hydrolysis of Kevlar. A model compound study of sulfuric-acid hydrolysis of aromatic amide was carried out in order to better understand the sulfuric-acid-hydrolysis of Kevlar.

  6. One-pot synthesis of amino acid precursors with insoluble organic matter in planetesimals with aqueous activity.

    PubMed

    Kebukawa, Yoko; Chan, Queenie H S; Tachibana, Shogo; Kobayashi, Kensei; Zolensky, Michael E

    2017-03-01

    The exogenous delivery of organic molecules could have played an important role in the emergence of life on the early Earth. Carbonaceous chondrites are known to contain indigenous amino acids as well as various organic compounds and complex macromolecular materials, such as the so-called insoluble organic matter (IOM), but the origins of the organic matter are still subject to debate. We report that the water-soluble amino acid precursors are synthesized from formaldehyde, glycolaldehyde, and ammonia with the presence of liquid water, simultaneously with macromolecular organic solids similar to the chondritic IOM. Amino acid products from hydrothermal experiments after acid hydrolysis include α-, β-, and γ-amino acids up to five carbons, for which relative abundances are similar to those extracted from carbonaceous chondrites. One-pot aqueous processing from simple ubiquitous molecules can thus produce a wide variety of meteoritic organic matter from amino acid precursors to macromolecular IOM in chondrite parent bodies.

  7. One-pot synthesis of amino acid precursors with insoluble organic matter in planetesimals with aqueous activity

    PubMed Central

    Kebukawa, Yoko; Chan, Queenie H. S.; Tachibana, Shogo; Kobayashi, Kensei; Zolensky, Michael E.

    2017-01-01

    The exogenous delivery of organic molecules could have played an important role in the emergence of life on the early Earth. Carbonaceous chondrites are known to contain indigenous amino acids as well as various organic compounds and complex macromolecular materials, such as the so-called insoluble organic matter (IOM), but the origins of the organic matter are still subject to debate. We report that the water-soluble amino acid precursors are synthesized from formaldehyde, glycolaldehyde, and ammonia with the presence of liquid water, simultaneously with macromolecular organic solids similar to the chondritic IOM. Amino acid products from hydrothermal experiments after acid hydrolysis include α-, β-, and γ-amino acids up to five carbons, for which relative abundances are similar to those extracted from carbonaceous chondrites. One-pot aqueous processing from simple ubiquitous molecules can thus produce a wide variety of meteoritic organic matter from amino acid precursors to macromolecular IOM in chondrite parent bodies. PMID:28345041

  8. Poly(N-vinylimidazole) gels as insoluble buffers that neutralize acid solutions without dissolving.

    PubMed

    Horta, Arturo; Piérola, Inés F

    2009-04-02

    Typical buffers are solutions containing weak acids or bases. If these groups were anchored to insoluble gels, what would be their behavior? Simple thermodynamics is used to calculate the pH in two-phase systems that contain the weak acid or base fixed to only one of the phases and is absent in the other. The experimental reference of such systems are pH sensitive hydrogels and heterogeneous systems of biological interest. It is predicted that a basic hydrogel immersed in slightly acidic solutions should absorb the acid and leave the external solution exactly neutral (pH 7). This is in accordance with experimental results of cross-linked poly(N-vinylimidazole). The pH 7 cannot be obtained if the system were homogeneous; the confinement of the weak base inside the gel phase is a requisite for this neutral pH in the external solution. The solution inside the gel is regulated to a much higher pH, which has important implications in studies on chemical reactions and physical processes taking place inside a phase insoluble but in contact with a solution.

  9. Inhibition of cold insolubility of an IgA cryoglobulin by decanedicarboxylic acid and related compounds.

    PubMed

    Lalezari, P; Kumar, M; Kumar, K M; Lawrence, C

    1983-11-01

    Cold insolubility of a serum IgA cryoimmunoglobulin was found to be inhibited by the addition of 1.5 mM sodium decanedicarboxylate in vitro. The patient with the cryoglobulin had advanced multiple myeloma complicated by severe hyperviscosity that caused lethargy and episodic loss of consciousness. Decanedicarboxylic acid administered orally resulted in transient relief of symptoms and the loss of cryoprecipitability of the paraprotein. Further in vitro studies revealed that sodium salts of long-chain monocarboxylic acids with a minimum of eight carbons, and dicarboxylic acids with a minimum of 12 carbons inhibited cryoprecipitation. Salts of short-chain carboxylic acids, by contrast, enhanced cryoprecipitation. Sodium phenolate and sodium salts of benzoic acid, 2,4-DNP, phenylpropionic acid, and salicylic acid were also inhibitory. These latter compounds, which have a ring structure, did not cause precipitation at any concentration. It was demonstrated that the presence of a free carboxylic group was required for these activities; conversion of carboxylic acid to amide resulted in the loss of both the inhibitory and cryoprecipitation-enhancing effects. Normal plasma, or plasma from five other patients who had IgG, IgM, or mixed-type cryoglobulinemia, were not affected by any of these compounds. It is suggested that in selected cases of hyperviscosity syndrome associated with cryoglobulinemia, some of these compounds, especially monocarboxylic acids with appropriate chain lengths, or those with a ring structure, may have therapeutic applications.

  10. Micellar acid-base potentiometric titrations of weak acidic and/or insoluble drugs.

    PubMed

    Gerakis, A M; Koupparis, M A; Efstathiou, C E

    1993-01-01

    The effect of various surfactants [the cationics cetyl trimethyl ammonium bromide (CTAB) and cetyl pyridinium chloride (CPC), the anionic sodium dodecyl sulphate (SDS), and the nonionic polysorbate 80 (Tween 80)] on the solubility and ionization constant of some sparingly soluble weak acids of pharmaceutical interest was studied. Benzoic acid (and its 3-methyl-, 3-nitro-, and 4-tert-butyl-derivatives), acetylsalicylic acid, naproxen and iopanoic acid were chosen as model examples. Precise and accurate acid-base titrations in micellar systems were made feasible using a microcomputer-controlled titrator. The response curve, response time and potential drift of the glass electrode in the micellar systems were examined. The cationics CTAB and CPC were found to increase considerably the ionization constant of the weak acids (delta pKa ranged from -0.21 to -3.57), while the anionic SDS showed negligible effect and the nonionic Tween 80 generally decreased the ionization constants. The solubility of the acids in aqueous micellar and acidified micellar solutions was studied spectrophotometrically and it was found increased in all cases. Acetylsalicylic acid, naproxen, benzoic acid and iopanoic acid could be easily determined in raw material and some of them in pharmaceutical preparations by direct titration in CTAB-micellar system instead of using the traditional non-aqueous or back titrimetry. Precisions of 0.3-4.3% RSD and good correlation with the official tedious methods were obtained. The interference study of some excipients showed that a preliminary test should be carried out before the assay of formulations.

  11. Activation of Transient Receptor Potential Ankyrin-1 by Insoluble Particulate Material and Association with Asthma.

    PubMed

    Deering-Rice, Cassandra E; Shapiro, Darien; Romero, Erin G; Stockmann, Chris; Bevans, Tatjana S; Phan, Quang M; Stone, Bryan L; Fassl, Bernhard; Nkoy, Flory; Uchida, Derek A; Ward, Robert M; Veranth, John M; Reilly, Christopher A

    2015-12-01

    Inhaled irritants activate transient receptor potential ankyrin-1 (TRPA1), resulting in cough, bronchoconstriction, and inflammation/edema. TRPA1 is also implicated in the pathogenesis of asthma. Our hypothesis was that particulate materials activate TRPA1 via a mechanism distinct from chemical agonists and that, in a cohort of children with asthma living in a location prone to high levels of air pollution, expression of uniquely sensitive forms of TRPA1 may correlate with reduced asthma control. Variant forms of TRPA1 were constructed by mutating residues in known functional elements and corresponding to single-nucleotide polymorphisms in functional domains. TRPA1 activity was studied in transfected HEK-293 cells using allyl-isothiocynate, a model soluble electrophilic agonist; 3,5-ditert butylphenol, a soluble nonelectrophilic agonist and a component of diesel exhaust particles; and insoluble coal fly ash (CFA) particles. The N-terminal variants R3C and R58T exhibited greater, but not additive, activity with all three agonists. The ankyrin repeat domain-4 single nucleotide polymorphisms E179K and K186N exhibited decreased response to CFA. The predicted N-linked glycosylation site residues N747A and N753A exhibited decreased responses to CFA, which were not attributable to differences in cellular localization. The pore-loop residue R919Q was comparable to wild-type, whereas N954T was inactive to soluble agonists but not CFA. These data identify roles for ankyrin domain-4, cell surface N-linked glycans, and selected pore-loop domain residues in the activation of TRPA1 by insoluble particles. Furthermore, the R3C and R58T polymorphisms correlated with reduced asthma control for some children, which suggest that TRPA1 activity may modulate asthma, particularly among individuals living in locations prone to high levels of air pollution.

  12. Saussurea lappa inhibits the growth, acid production, adhesion, and water-insoluble glucan synthesis of Streptococcus mutans.

    PubMed

    Yu, Hyeon-Hee; Lee, Jun-Sup; Lee, Ki-Hyun; Kim, Ki-Young; You, Yong-Ouk

    2007-05-04

    In the present study, inhibitory effects of the ethanol extract of Saussurea lappa (S. lappa) on the growth, acid production, adhesion, and water-insoluble glucan synthesis of Streptococcus mutans (S. mutans) were examined. The growth and acid production of Streptococcus mutans were inhibited by the presence of ethanol extract of Saussurea lappa (0.5-4 mg/ml) significantly. The ethanol extract of Saussurea lappa (0.25-4 mg/ml) also significantly lowered the adherence of Streptococcus mutans in a dose dependent manner. In water-insoluble glucan synthesis assay, 2-4 mg/ml of the ethanol extract of Saussurea lappa significantly inhibited the formation of water-insoluble glucan. These results suggest that Saussurea lappa may inhibit the caries-inducing properties of Streptococcus mutans. Further studies are necessary to clarify the active constituents of Saussurea lappa responsible for such biomolecular activities.

  13. Hyaluronic acid-supported combination of water insoluble immunostimulatory compounds for anti-cancer immunotherapy.

    PubMed

    Shin, Woo Jung; Noh, Hyun Jong; Noh, Young-Woock; Kim, Sohyun; Um, Soong Ho; Lim, Yong Taik

    2017-01-02

    A novel powder-form combination adjuvant system containing two immunostimulatory compounds was firstly developed and evaluated as a therapeutic intervention for cancer immunotherapy. With the help of hyaluronic acid (HA), water insoluble monophosphoryl lipid A (MPL), QS21 and imiquimod (R837), could be easily dispersed in aqueous solution and lyophilized as powder-form, which have an advantage in room-temperature storage stability compared with those conventional liquid formulation that requires cold storage. Two kinds of HA-based combination vaccine adjuvants (HA/MPL/QS21, HMQ and HA/MPL/R837, HMR) contributed to the increase of both humoral and cellular immunity, which is very important for efficient cancer immunotherapy. Through the challenge experiments in EG7-OVA (mouse lymphoma-expressing OVA) tumor-bearing mice model, we found out that the immunostimulatory effects of HMQ and HMR were successful in the inhibition of tumor proliferation. Taken together, both HA-based powder-form combination adjuvant systems are expected to be used as potent prophylactic and therapeutic cancer vaccine.

  14. Purification and biochemical characterization of insoluble acid invertase (INAC-INV) from pea seedlings.

    PubMed

    Kim, Donggiun; Lee, Gunsup; Chang, Man; Park, Jongbum; Chung, Youngjae; Lee, Sukchan; Lee, Taek-Kyun

    2011-10-26

    Invertase (EC 3.2.1.26) catalyzes the hydrolysis of sucrose into D-glucose and D-fructose. Insoluble acid invertase (INAC-INV) was purified from pea (Pisum sativum L.) by sequential procedures entailing ammonium sulfate precipitation, ion exchange chromatography, absorption chromatography, reactive green-19 affinity chromatography, and gel filtration. The purified INAC-INV had a pH optimum of 4.0 and a temperature optimum of 45 °C. The effects of various concentrations of Tris-HCl, HgCl(2), and CuSO(4) on the activities of the purified invertase were examined. INAC-INV was not affected by Tris-HCl and HgCl(2). INAC-INV activity was inhibited by 6.2 mM CuSO(4) up to 50%. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The K(m) and V(max) values of INAC-INV were determined to be 4.41 mM and 8.41 U (mg protein)(-1) min(-1), respectively. INAC-INV is a true member of the β-fructofuranosidases, which can react with sucrose and raffinose as substrates. SDS-PAGE and immunoblotting were used to determine the molecular mass of INAC-INV to be 69 kDa. The isoelectric point of INAC-INV was estimated to be about pH 8.0. Taken together, INAC-INV is a pea seedling invertase with a stable and optimum activity at lower acid pH and at higher temperature than other invertases.

  15. The Insoluble Carbonaceous Material of CM Chondrites as Possible Source of Discrete Organics During the Asteroidal Aqueous Phase

    NASA Technical Reports Server (NTRS)

    Yabuta, H.; Williams, L.; Cody, G.; Pizzarello, S.

    2005-01-01

    The larger portion of the organic carbon in carbonaceous chondrites (CC) is present as a complex and heterogeneous macromolecular material that is insoluble in acids and most solvents (IOM). So far, it has been analyzed only as a whole by microscopy (TEM) and spectroscopy (IR, NMR, EPR), which have offered and overview of its chemical nature, bonding, and functional group composition. Chemical or pyrolytic decomposition has also been used in combination with GC-MS to identify individual compounds released by these processes. Their value in the recognition of the original IOM structure resides in the ability to properly interpret the decomposition pathways for any given process. We report here a preliminary study of IOM from the Murray meteorite that combines both the analytical approaches described above, under conditions that would realistically model the IOM hydrothermal exposure in the meteorite parent body. The aim is to document the possible release of water and solvent soluble organics, determine possible changes in NMR spectral features, and ascertain, by extension, the effect of this loss on the frame of the IOM residue. Additional information is included in the original extended abstract.

  16. Homogenization-dependent responses of acid-soluble and acid-insoluble glycogen to exercise and refeeding in human muscles.

    PubMed

    Barnes, Phillip D; Singh, Anish; Fournier, Paul A

    2009-12-01

    Muscle glycogen exists as acid-insoluble (AIG) and acid-soluble (ASG) forms, with AIG levels reported in most recent studies in humans to be the most responsive to exercise and refeeding. Because the muscle samples in these studies were not homogenized to extract glycogen, such homogenization-free protocols might have resulted in a suboptimal yield of ASG. Our goal, therefore, was to determine whether similar findings can be achieved using homogenized muscle samples by comparing the effect of exercise and refeeding on ASG and AIG levels. Eight male participants cycled for 60 minutes at 70% Vo(2peak) before ingesting 10.9 +/- 0.6 g carbohydrate per kilogram body mass over 24 hours. Muscle biopsies were taken before exercise and after 0, 2, and 24 hours of recovery. Using a homogenization-dependent protocol to extract glycogen, 77% to 91% of it was extracted as ASG, compared with 11% to 24% with a homogenization-free protocol. In response to exercise, muscle glycogen levels fell from 366 +/- 24 to 184 +/- 46 mmol/kg dry weight and returned to 232 +/- 32 and 503 +/- 59 mmol/kg dry weight after 2 and 24 hours, respectively. Acid-soluble glycogen but not AIG accounted for all the changes in total glycogen during exercise and refeeding when extracted using a homogenization-dependent protocol, but AIG was the most responsive fraction when extracted using a homogenization-free protocol. In conclusion, the patterns of response of ASG and AIG levels to changes in glycogen concentrations in human muscles are highly dependent on the protocol used to acid-extract glycogen, with the physiologic significance of the many previous studies on AIG and ASG being in need of revision.

  17. Effect of extrusion processing on the soluble and insoluble fiber, and phytic acid contents of cereal brans.

    PubMed

    Gualberto, D G; Bergman, C J; Kazemzadeh, M; Weber, C W

    1997-01-01

    The health benefits associated with dietary fiber have resulted in it now being used in virtually all food product categories, including many products which are manufactured using extrusion processing. The objective of the present study was to determine if extrusion processing affected phytic acid, and soluble and insoluble fiber contents. The effect of screw speeds of 50, 70, and 100% of maximum rotations per minute (% MRPM) on these components was investigated. A BI-EX Model DNDG-62/20D co-rotating intermeshing self-cleaning twin-screw extruder, manufactured by Bühlerag, CH-9240, Uzwil, Switzerland, was used to process wheat, oat and rice brans. It was found that extrusion did not affect the insoluble fiber content of wheat bran; however, a decrease in this component was observed in rice and oat brans. The effect on rice bran insoluble fiber was greatest at screw speeds of 50 and 70% MRPM. This occurred in oat bran at 50% MRPM. Soluble fiber content increased in all brans after extrusion, except ER100. For oat and rice bran soluble fibers, the greatest increase occurred at 50 and 70% MRPM, while for wheat bran this occurred at 70 and 100% MRPM. Extrusion did not affect the phytate content of the cereal brans.

  18. Using acid insoluble ash marker ratios (diet:digesta) to predict digestibility of wheat and barley metabolizable energy and nitrogen retention in broiler chicks.

    PubMed

    Scott, T A; Hall, J W

    1998-05-01

    Routine bioassay measurements of AME or N retention of broiler diets require measurements of gross energy (GE) or N and an acid insoluble ash marker in diet, excreta, or ileal digesta. These measurements of GE and N are time-consuming and expensive in comparison to measurements of added or natural occurring levels of acid insoluble ash. Data from bioassay measurements of AME and N retention of 138 wheat and 97 barley samples (with or without enzyme) were used to develop prediction equations relying on measurements of one that uses acid insoluble ash of diet, excreta or ileal digesta and GE and N of diet only; and a second equation using only acid insoluble ash of diet, excreta, or ileal digesta. The prediction equations demonstrate that part of or all of routine bomb calorimetry measurements for GE used to determine AME of wheat- or barley-based diets could be eliminated if a prediction error of 80 kcal/kg ME or less were acceptable. The prediction of N retention as compared to AME, based in part or totally on acid insoluble ash measurements, was less accurate; the prediction errors were equal to 2.3 and 6.5% for wheat- and barley-based diets, respectively. Ongoing research to improve the determination (speed, ease, and accuracy) of acid insoluble ash could provide a useful method to assess feeding value of ingredients and commercial poultry diets.

  19. Determination of trace metals using laser induced breakdown spectroscopy in insoluble organic materials obtained from pyrolysis of plastics waste.

    PubMed

    Siddiqui, Mohammad N; Gondal, Mohammad A; Nasr, Mohammed M

    2009-07-01

    Laser induced breakdown spectroscopy (LIBS) was applied for the detection of trace elements in non-degradable part of plastics known as insoluble organic material, obtained from thermal and catalytic degradation of plastics. LIBS signal intensity for each metal measured in the test sample was unique and different. The capability of this technique is demonstrated by analyzing various trace metals present inside plastics and also compared with ICP results. The metal concentration (ppm) measured with LIBS and verified by ICP for Ag (901), Al (522), Fe (231), Co (628), V (275), Ni (558), Pb (325), Mn (167) and Cd (378) are higher than permissible safe limits.

  20. [The effect of a diet containing long-chain fatty acids on the formation of insoluble elastin in the rat aorta].

    PubMed

    Wimmerová, J; Benesová, J; Hartmanová, M; Subrtová, D; Stoklasová, A; Ledvina, M

    1989-01-01

    The paper deals with the influence of long-chain fatty acids on the formation of insoluble elastin in vivo. Oil isolated from the sea fish named flounder has been chosen as the source of those long-chain fatty acids. The diet containing the flounder oil was administered to pregnant rat females. The influence of fatty acids on the formation of insoluble elastin was evaluated according to the percentage changes of insoluble elastin in the aortas of newborn rats and to the changes of the amount of desmosine cross-links in isolated elastin. The administration of the diet with long-chain fatty acids causes no changes in the content of elastin in the aortas of the new-born rats, meanwhile the amount of desmosine increases considerably. The results on the aortas of new-born rats shown here are in good agreement with the changes on the aortas of 3-month-old rats published in a previous paper.

  1. Petroleum pollution bioremediation using water-insoluble uric acid as the nitrogen source.

    PubMed

    Koren, Omry; Knezevic, Vishnia; Ron, Eliora Z; Rosenberg, Eugene

    2003-10-01

    The biodegradation of hydrocarbon pollutants in open systems is limited by the availability of a utilizable nitrogen source. This limitation can be overcome by using uric acid. Enrichment cultures grown on crude oil-uric acid media yielded mixed and pure cultures that degraded petroleum. In a simulated open system, uric acid bound to crude oil and was available for bacterial growth and petroleum biodegradation.

  2. Production of furfural from xylose, water-insoluble hemicelluloses and water-soluble fraction of corncob via a tin-loaded montmorillonite solid acid catalyst.

    PubMed

    Li, Huiling; Ren, Junli; Zhong, Linjie; Sun, Runcang; Liang, Lei

    2015-01-01

    The conversion of xylose, water-insoluble hemicelluloses (WIH) and water-soluble fraction (WSF) of corncob to furfural was performed using montmorillonite with tin ions (Sn-MMT) containing double acid sites as a solid acid catalyst. The co-existence of Lewis acids and Brønsted acids in Sn-MMT was shown to improve the furfural yield and selectivity. 76.79% furfural yield and 82.45% furfural selectivity were obtained from xylose using Sn-MMT as a catalyst in a biphasic system with 2-s-butylphenol (SBP) as the organic extracting layer and dimethyl sulfoxide (DMSO) as the co-solvent in contact with an aqueous phase saturated with NaCl (SBP/NaCl-DMSO) at 180°C for 30min. Furthermore, Sn-MMT also demonstrated the excellent catalytic performance in the conversion of pentose-rich materials of corncob and 39.56% and 54.15% furfural yields can be directly obtained from WIH and WSF in the SBP/NaCl-DMSO system, respectively.

  3. Potential toxicity of presumably insoluble aluminum salts in presence of common dietary acids.

    PubMed

    Dayde, S; Berthon, G

    1990-01-01

    It has recently been shown that aluminum absorption may occur following the administration of oral aluminium-containing phosphate-binders and antacids. Computer simulations based on relevant aluminium complex equilibria have been used in the present work to investigate the potential influence of the simultaneous ingestion of common dietary acids on this phenomenon. It results from these studies that aluminium absorption may be favoured to various extents in the presence of citric, malic, oxalic, succinic and tartric acids.

  4. Glucansucrases from lactic acid bacteria which produce water-insoluble polysaccharides from sucrose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dextrans and related glucans produced from sucrose by lactic acid bacteria have been studied for many years and are used in numerous commercial applications and products. Most of these glucans are water-soluble, except for a few notable exceptions from cariogenic Streptococcus spp. and a very small ...

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

  6. Potent inhibitory effects of D-tagatose on the acid production and water-insoluble glucan synthesis of Streptococcus mutans GS5 in the presence of sucrose.

    PubMed

    Sawada, Daijo; Ogawa, Takaaki; Miyake, Minoru; Hasui, Yoshinori; Yamaguchi, Fuminori; Izumori, Ken; Tokuda, Masaaki

    2015-01-01

    We examined and compared the inhibitory effects of D-tagatose on the growth, acid production, and water-insoluble glucan synthesis of GS5, a bacterial strain of Streptococcus mutans, with those of xylitol, D-psicose, L-psicose and L-tagatose. GS5 was cultured for 12h in a medium containing 10% (w/v) of xylitol, D-psicose, L-psicose, D-tagatose or L-tagatose, and the inhibitory effect of GS5 growth was assessed. Each sugar showed different inhibitory effects on GS5. Both D-tagatose and xylitol significantly inhibited the acid production and water-insoluble glucan synthesis of GS5 in the presence of 1% (w/v) sucrose. However, the inhibitory effect of acid production by D-tagatose was significantly stronger than that of xylitol in presence of sucrose.

  7. Incorporation of glycine-2-C-14 in acid-insoluble proteins of rat bones and teeth during hypokinesia and administration of thyrocalcitonine

    NASA Technical Reports Server (NTRS)

    Volozhin, A. I.; Stekolnikov, L. I.; Uglova, N. N.; Potkin, V. Y.

    1979-01-01

    A forced limitation of the motor activity in rats (from 5 to 60 days) results in reduced incorporation of glycine 2-C14 in the total acid insoluble proteins of limb bones and its increase in the teeth and mandibular-maxillary bones. Daily administration of five micrograms of thyrocalcitonine together with polyvinylpyrrolidone normalizes the protein metabolism in the bone tissues during the 40 days of experimentation.

  8. Chromic oxide and acid-insoluble ash as markers in digestibility studies with growing pigs and sows.

    PubMed

    Brestenský, M; Nitrayová, S; Heger, J; Patráš, P

    2017-02-01

    The results of three experiments, focused on the determination of endogenous ileal flow (EIF) of amino acids (AA) and nitrogen (N) (Exp. 1), apparent ileal digestibility (AID) of AA and N (Exp. 2), and apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), N, calcium (Ca) and phosphorus (P) (Exps. 2 and 3), were used to compare chromic oxide (Cr2 O3 ) and acid-insoluble ash (AIA) as digestibility markers. In Exps. 1 and 2, a total of six gilts fitted with T-cannula in terminal ileum, and in Exp. 3, a total of 24 pregnant sows were used. In Exps. 1 and 2, the pigs were assigned into four dietary treatments according to 4 × 6 crossover design (Exp. 1; diets with 0%, 4%, 8% and 12% of casein; Exp. 2 basal diet with different levels of phytase). In Exp. 3, the sows were assigned to four dietary treatments (basal diet with different levels of phytase) of six sows. In Exps. 1 and 2 ileal digesta and in Exps. 2 and 3 faeces were collected for the determination of EIF, AID and ATTD. Differences in EIF of AA determined by Cr2 O3 and AIA ranged (p ˃ 0.05) from -4.62 to 4.54%. The lowest EIF was for methionine and the greatest one for proline, determined by both markers. Apparent ileal digestibility determined by Cr2 O3 was slightly greater (p ˃ 0.05) in comparison with AIA. Differences ranged from 1.88% (Arg) to 7.08% (Gly). The greatest AID was for arginine and the lowest one for glycine, determined by both Cr2 O3 and AIA. Similarly for ATTD of DM, OM, N, Ca and P, there were no differences in digestibility determined by Cr2 O3 and AIA. Both, Cr2 O3 and AIA, are suitable and comparable markers for digestibility studies in pigs.

  9. Water-insoluble material from apple pomace makes changes in intracellular NAD⁺/NADH ratio and pyrophosphate content and stimulates fermentative production of hydrogen.

    PubMed

    Sato, Osamu; Suzuki, Yuma; Sato, Yuki; Sasaki, Shinsuke; Sonoki, Tomonori

    2015-05-01

    Apple pomace is one of the major agricultural residues in Aomori prefecture, Japan, and it would be useful to develop effective applications for it. As apple pomace contains easily fermentable sugars such as glucose, fructose and sucrose, it can be used as a feedstock for the fermentation of fuels and chemicals. We previously isolated a new hydrogen-producing bacterium, Clostridium beijerinckii HU-1, which could produce H2 at a production rate of 14.5 mmol of H2/L/h in a fed-batch culture at 37 °C, pH 6.0. In this work we found that the HU-1 strain produces H2 at an approximately 20% greater rate when the fermentation medium contains the water-insoluble material from apple pomace. The water-insoluble material from apple pomace caused a metabolic shift that stimulated H2 production. HU-1 showed a decrease of lactate production, which consumes NADH, accompanied by an increase of the intracellular pyrophosphate content, which is an inhibitor of lactate dehydrogenase. The intracellular NAD(+)/NADH ratios of HU-1 during H2 fermentation were maintained in a more reductive state than those observed without the addition of the water insoluble material. To correct the abnormal intracellular redox balance, caused by the repression of lactate production, H2 production with NADH oxidation must be stimulated.

  10. Effects of soluble and insoluble fractions from bilberries, black currants, and raspberries on short-chain fatty acid formation, anthocyanin excretion, and cholesterol in rats.

    PubMed

    Jakobsdottir, Greta; Nilsson, Ulf; Blanco, Narda; Sterner, Olov; Nyman, Margareta

    2014-05-14

    Dietary fiber and flavonoids, important components in berries, are suggested to improve metabolic health. This study investigates whether soluble and insoluble fractions isolated from bilberry, black currant, and raspberry affect the formation of short-chain fatty acids (SCFAs), uptake and excretion of flavonoids, and levels of cholesterol differently. Cecal SCFA pools were higher in rats fed the soluble than the insoluble fractions (525 vs 166 μmol, P < 0.001), whereas higher concentrations of butyric acid were found in the distal colon and serum of rats fed the insoluble fractions (5 vs 3 μmol/g and 58 vs 29 μmol/L, respectively, P < 0.001). The soluble bilberry fraction gave lower amounts of liver cholesterol (56 mg) than the other berry fractions (87 ± 5 mg), formed the highest amount of SCFAs (746 vs 266 ± 21 μmol), and contributed the highest intake of anthocyanins. Cyanidin-3-glucoside monoglucuronide was detected in the urine of all groups, whereas anthocyanins were found only in groups fed soluble black currant and raspberry.

  11. Catalyst Of A Metal Heteropoly Acid Salt That Is Insoluble In A Polar Solvent On A Non-Metallic Porous Support And Method Of Making

    DOEpatents

    Wang. Yong; Peden. Charles H. F.; Choi. Saemin

    2004-11-09

    The present invention includes a catalyst having (a) a non-metallic support having a plurality of pores; (b) a metal heteropoly acid salt that is insoluble in a polar solvent on the non-metallic support; wherein at least a portion of the metal heteropoly acid salt is dispersed within said plurality of pores. The present invention also includes a method of depositing a metal heteropoly acid salt that is insoluble in a polar solvent onto a non-metallic support having a plurality of pores. The method has the steps of: (a) obtaining a first solution containing a first precursor of a metal salt cation; (b) obtaining a second solution containing a second precursor of a heteropoly acid anion in a solvent having a limited dissolution potential for said first precursor; (c) impregnating the non-metallic support with the first precursor forming a first precursor deposit within the plurality of pores, forming a first precursor impregnated support; (d) heating said first precursor impregnated support forming a bonded first precursor impregnated support; (e) impregnating the second precursor that reacts with the precursor deposit and forms the metal heteropoly acid salt.

  12. Catalyst of a metal heteropoly acid salt that is insoluble in a polar solvent on a non-metallic porous support and method of making

    DOEpatents

    Wang, Yong [Richland, WA; Peden, Charles H. F. [West Richland, WA; Choi, Saemin [Richland, WA

    2002-10-29

    The present invention includes a catalyst having (a) a non-metallic support having a plurality of pores; (b) a metal heteropoly acid salt that is insoluble in a polar solvent on the non-metallic support; wherein at least a portion of the metal heteropoly acid salt is dispersed within said plurality of pores. The present invention also includes a method of depositing a metal heteropoly acid salt that is insoluble in a polar solvent onto a non-metallic support having a plurality of pores. The method has the steps of: (a) obtaining a first solution containing a first precursor of a metal salt cation; (b) obtaining a second solution containing a second precursor of a heteropoly acid anion in a solvent having a limited dissolution potential for said first precursor; (c) impregnating the non-metallic support with the first precursor forming a first precursor deposit within the plurality of pores, forming a first precursor impregnated support; (d) heating said first precursor impregnated support forming a bonded first precursor impregnated support; (e) impregnating the second precursor that reacts with the precursor deposit and forms the metal heteropoly acid salt.

  13. Statistical quality control of total ash, acid-insoluble ash, loss on drying, and hazardous heavy metals contained in the component medicinal herbs of "Ssanghwatang", a widely used oriental formula in Korea.

    PubMed

    Kim, Donggyu; Kim, Bogsoon; Yun, Eunsun; Kim, Junghun; Chae, Youngzoo; Park, Seungkook

    2013-01-01

    To investigate the current quality control status of raw materials in "Ssanghwatang", a widely used oriental formula effective for fatigue recovery in Korea, 1024 samples of 9 herbs available in Seoul area markets were collected, and the contents of quality inspection items such as total ash, acid-insoluble ash, loss on drying, and hazardous heavy metals (Pb, As, Cd, Hg) were examined. Medicinal herbs requiring quality control, which may not meet the specifications and standards set by the Korea Food and Drug Administration, were selected using robust z-scores, a random variable. Among the quality control items, control of total ash content was required for the Ssanghwatang raw materials Cinnamomi Cortex, Rehmanniae Radix Preparata, Zingiberis Rhizoma, and Zizyphi Fructus; loss on drying for Cinnamomi Cortex; and heavy metal (Cd) for Angelicae Gigantis Radix, Cinnamomi Cortex, and Zingiberis Rhizoma. Additionally, acid-insoluble ash content revealed how many fine soil and sand particles are present in commercial medicinal herbs, which were correlated with heavy metals such as Pb (r = 0.528) and As (r = 0.342) in Rehmanniae Radix Preparata (p < 0.01).

  14. Evolution of insoluble eutectic Si particles in anodic oxidation films during adipic-sulfuric acid anodizing processes of ZL114A aluminum alloys

    NASA Astrophysics Data System (ADS)

    Hua, Lei; Liu, Jian-hua; Li, Song-mei; Yu, Mei; Wang, Lei; Cui, Yong-xin

    2015-03-01

    The effects of insoluble eutectic Si particles on the growth of anodic oxide films on ZL114A aluminum alloy substrates were investigated by optical microscopy (OM) and scanning electron microscopy (SEM). The anodic oxidation was performed at 25°C and a constant voltage of 15 V in a solution containing 50 g/L sulfuric acid and 10 g/L adipic acid. The thickness of the formed anodic oxidation film was approximately 7.13 μm. The interpore distance and the diameters of the major pores in the porous layer of the film were within the approximate ranges of 10-20 nm and 5-10 nm, respectively. Insoluble eutectic Si particles strongly influenced the morphology of the anodic oxidation films. The anodic oxidation films exhibited minimal defects and a uniform thickness on the ZL114A substrates; in contrast, when the front of the oxide oxidation films encountered eutectic Si particles, defects such as pits and non-uniform thickness were observed, and pits were observed in the films.

  15. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Insoluble wastes. 227.12 Section 227.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR... Insoluble wastes. (a) Solid wastes consisting of inert natural minerals or materials compatible with...

  16. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Insoluble wastes. 227.12 Section 227.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR... Insoluble wastes. (a) Solid wastes consisting of inert natural minerals or materials compatible with...

  17. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Insoluble wastes. 227.12 Section 227.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR... Insoluble wastes. (a) Solid wastes consisting of inert natural minerals or materials compatible with...

  18. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Insoluble wastes. 227.12 Section 227.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR... Insoluble wastes. (a) Solid wastes consisting of inert natural minerals or materials compatible with...

  19. Functionalization of carbon nanotubes with water-insoluble porphyrin in ionic liquid: direct electrochemistry and highly sensitive amperometric biosensing for trichloroacetic acid.

    PubMed

    Tu, Wenwen; Lei, Jianping; Ju, Huangxian

    2009-01-01

    A functional composite of single-walled carbon nanotubes (SWNTs) with hematin, a water-insoluble porphyrin, was first prepared in 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]) ionic liquid. The novel composite in ionic liquid was characterized by scanning electron microscopy, ultraviolet absorption spectroscopy, and electrochemical impedance spectroscopy, and showed a pair of direct redox peaks of the Fe(III)/Fe(II) couple. The composite-[BMIM][PF(6)]-modified glassy carbon electrode showed excellent electrocatalytic activity toward the reduction of trichloroacetic acid (TCA) in neutral media due to the synergic effect among SWNTs, [BMIM][PF(6)], and porphyrin, which led to a highly sensitive and stable amperometric biosensor for TCA with a linear range from 9.0x10(-7) to 1.4x10(-4) M. The detection limit was 3.8x10(-7) M at a signal-to-noise ratio of 3. The TCA biosensor had good analytical performance, such as rapid response, good reproducibility, and acceptable accuracy, and could be successfully used for the detection of residual TCA in polluted water. The functional composite in ionic liquid provides a facile way to not only obtain the direct electrochemistry of water-insoluble porphyrin, but also construct novel biosensors for monitoring analytes in real environmental samples.

  20. Soluble vs. insoluble fiber

    MedlinePlus

    ... soluble and insoluble. Both are important for health, digestion, and preventing diseases. Soluble fiber attracts water and turns to gel during digestion. This slows digestion. Soluble fiber is found in ...

  1. Lyophilized wafers comprising carrageenan and pluronic acid for buccal drug delivery using model soluble and insoluble drugs.

    PubMed

    Kianfar, Farnoosh; Antonijevic, Milan; Chowdhry, Babur; Boateng, Joshua S

    2013-03-01

    Lyophilized muco-adhesive wafers with optimum drug loading for potential buccal delivery have been developed. A freeze-annealing cycle was used to obtain optimized wafers from aqueous gels containing 2% κ-carrageenan (CAR 911), 4% pluronic acid (F127), 4.4% (w/w) polyethylene glycol with 1.8% (w/w) paracetamol or 0.8% (w/w) ibuprofen. Thermogravimetric analysis showed acceptable water content between 0.9 and 1.5%. Differential scanning calorimetry and X-ray diffraction showed amorphous conversion for both drugs. Texture analysis showed ideal mechanical and mucoadhesion characteristics whilst both drugs remained stable over 6 months and drug dissolution at a salivary pH showed gradual release within 2h. The results show the potential of CAR 911 and F127 based wafers for buccal mucosa drug delivery.

  2. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw.

    PubMed

    Li, Yanfei; Ge, Xiaoyan; Sun, Zongping; Zhang, Junhua

    2015-06-01

    The competitive adsorption between cellulases and additives on lignin in the hydrolysis of lignocelluloses has been confirmed, whereas the effect of additives on the interaction between xylanase and lignin is not clear. In this work, the effects of additives, poly(ethylene glycol) 2000, poly(ethylene glycol) 6000, Tween 20, and Tween 80, on the xylanase adsorption/desorption onto/from acid-insoluble lignin from corn stover (CS-lignin) and wheat straw (WS-lignin) were investigated. The results indicated that the additives could adsorb onto isolated lignin and reduce the xylanase adsorption onto lignin. Compared to CS-lignin, more additives could adsorb onto WS-lignin, making less xylanase adsorbed onto WS-lignin. In addition, the additives could enhance desorption of xylanase from lignin, which might be due to the competitive adsorption between xylanase and additives on lignin. The released xylanase from lignin still exhibited hydrolytic capacity in the hydrolysis of isolated xylan and xylan in corn stover.

  3. Apparent digestibility of wheat bran and extruded flax in horses determined from the total collection of feces and acid-insoluble ash as an internal marker.

    PubMed

    De Marco, M; Miraglia, N; Peiretti, P G; Bergero, D

    2012-02-01

    Several studies have reported data on comparisons between two methods: the total collection of feces and the internal markers method. The aim of this study was to assess the apparent digestibility of two concentrates and to compare the apparent digestion coefficients using the total collection of feces and acid-insoluble ash (AIA) as the internal marker method. In 2009, six adult geldings aged between 3 and 11 years, with an average weight per trial of 543, 540 and 542 kg, respectively, were used to determine the apparent digestibility by means of three in vivo digestibility trials on hay, hay plus wheat bran (60 : 40) and hay plus extruded flax (80 : 20). Feces were collected over a 6-day period with a previous 14-day adaptation period. The three digestibility trials were carried out to determine the digestion coefficients of the three diets and, indirectly, of the two concentrates. The digestion coefficients of the diets were determined for the dry matter, organic matter, crude protein and gross energy, whereas the apparent digestion coefficients of the same parameters were calculated for wheat bran and extruded flax, by calculating the difference from the previous results. The data were analyzed using the Student t-test for paired samples. The digestion coefficients obtained were similar when the total collection of feces and the AIA method were used. Higher data variability, confirmed by a greater standard deviation, was observed using the AIA method to estimate the apparent digestion coefficients. It can be concluded that the use of AIA as an internal marker in digestibility trials on average leads to values similar to those obtained with the total collection of feces and can therefore be considered a less-expensive method to determine apparent digestion coefficients. Nevertheless, the total collection of feces should still be considered the best choice to determine the digestibility of some specific feedstuffs.

  4. Effect of insoluble-low fermentable fiber from corn on energy, fiber, and amino acid digestibility, and on hindgut degradability of fiber and growth performance of pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive use of corn co-products in swine diets increases the concentration of dietary fiber, raising concerns about energy and nutrient digestibility, and ultimately on pig performance. A metabolism trial was conducted to determine the effect of increasing levels of insoluble-low fermentable fiber...

  5. 40 CFR 227.12 - Insoluble wastes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Insoluble wastes. 227.12 Section 227.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE... wastes. (a) Solid wastes consisting of inert natural minerals or materials compatible with the...

  6. [Prebiotic phosphate: a problem insoluble in water ? ].

    PubMed

    Morchio, Renzo; Traverso, Silvano

    2005-01-01

    It is well-known that in water phosphate readily reacts with calcium, precipitating as insoluble apatite. How phosphorus could have been available for prebiotic reactions is still an open problem. We suggest that phosphorus-containing compounds might have accumulated in a hydrophobic medium, since the absence of calcium ions would have prevented them from precipitating as apatite. Hydrophobic compounds may have been synthesized on the early Earth through the polymerization of methane or through Fischer-Tropsch-type reactions. Moreover, hydrophobic compounds would have been delivered to the early Earth by extraterrestrial infall. In previous articles (Morchio and Traverso [1999], Morchio et al. [2001]) we suggested that such hydrophobic material would have formed a hydrophobic layer on the surface of the sea, which would have provided an environment thermodynamically more suitable than water for the concentration and polymerization of organic molecules fundamental to life, particularly amino acids and (pyrimidine) bases. It may be hypothesized that elemental phosphorus or phosphorus-containing compounds (such as phosphite) deriving from volcanic eruptions would have ended up raining down into the hydrophobic layer, accumulating due to the absence of calcium ions, in an environment protected against hydrolysis. Phosphorus-containing compounds might have interacted with hydrophobic molecules in the layer giving rise to polymers. In particular, phosphite might have reacted with the hydrophobic amino acids, giving rise to phosphoamino acids, which, in turn, might have interacted with pyrimidine bases (relatively abundant in the layer) giving rise to peptides and oligonucleotide-like polymers. Indeed, it has been experimentally shown (Zhou et al. [1996]) that, in an anhydrous organic medium (pyridine), dialkilphosphite reacts with amino acids to form phosphoamino acids, which interact with pyrimidine nucleosides to give nucleotides, short oligonucleotides and phosphoryl

  7. Acid soluble, pepsin resistant platelet aggregating material

    SciTech Connect

    Schneider, M.D.

    1982-08-31

    Disclosed is an acid soluble, pepsin resistant, platelet aggregating material isolated from equine arterial tissue by extraction with dilute aqueous acid. The method of isolation and use to control bleeding are described. 4 figs.

  8. In-depth proteomic analysis of a mollusc shell: acid-soluble and acid-insoluble matrix of the limpet Lottia gigantea

    PubMed Central

    2012-01-01

    Background Invertebrate biominerals are characterized by their extraordinary functionality and physical properties, such as strength, stiffness and toughness that by far exceed those of the pure mineral component of such composites. This is attributed to the organic matrix, secreted by specialized cells, which pervades and envelops the mineral crystals. Despite the obvious importance of the protein fraction of the organic matrix, only few in-depth proteomic studies have been performed due to the lack of comprehensive protein sequence databases. The recent public release of the gastropod Lottia gigantea genome sequence and the associated protein sequence database provides for the first time the opportunity to do a state-of-the-art proteomic in-depth analysis of the organic matrix of a mollusc shell. Results Using three different sodium hypochlorite washing protocols before shell demineralization, a total of 569 proteins were identified in Lottia gigantea shell matrix. Of these, 311 were assembled in a consensus proteome comprising identifications contained in all proteomes irrespective of shell cleaning procedure. Some of these proteins were similar in amino acid sequence, amino acid composition, or domain structure to proteins identified previously in different bivalve or gastropod shells, such as BMSP, dermatopontin, nacrein, perlustrin, perlucin, or Pif. In addition there were dozens of previously uncharacterized proteins, many containing repeated short linear motifs or homorepeats. Such proteins may play a role in shell matrix construction or control of mineralization processes. Conclusions The organic matrix of Lottia gigantea shells is a complex mixture of proteins comprising possible homologs of some previously characterized mollusc shell proteins, but also many novel proteins with a possible function in biomineralization as framework building blocks or as regulatory components. We hope that this data set, the most comprehensive available at present, will

  9. Comparison of acid-detergent lignin, alkaline-peroxide lignin, and acid-detergent insoluble ash as internal markers for predicting fecal output and digestibility by cattle offered bermudagrass hays of varying nutrient composition

    PubMed Central

    2014-01-01

    Background The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle offered bermudagrass [Cynodon dactylon (L.) Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 hay diets: low (L), medium low (ML), medium high (MH), and high (H) crude protein (CP) concentration (79, 111, 131, and 164 g CP/kg on a DM basis, respectively). Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08:00 and 16:00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake (DMI), DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results Forage DMI was affected by diet (P = 0.02), and DMI from MH and H was greater (P < 0.05) than from L. Apparent DMD tended (P = 0.08) to differ among diets while FO (P = 0.20) was not affected by diet treatments. Average ADL recovery (1.16) was greater (P < 0.05) than that of ADIA (1.03) and APL (1.06), but ADIA and APL did not differ (P = 0.42). Estimates of FO and DMD derived using APL and ADIA were not different (P ≥ 0.05) from total fecal collection while those using ADL differed (P < 0.05). There was no diet by marker interaction (P ≥ 0.22) for either FO or DMD. Conclusion Acid-detergent insoluble ash and APL accurately predicted FO and DMD of cattle fed bermudagrass hay of varying nutrient composition. These internal markers may facilitate studies involving large numbers of animals and forages. Results from such studies may be used to develop improved equations to predict energy values of

  10. Acid Rain: Resource Materials for Schools.

    ERIC Educational Resources Information Center

    American Biology Teacher, 1983

    1983-01-01

    Provides listings of acid rain resource material groups under: (1) printed materials (pamphlets, books, articles); (2) audiovisuals (slide/tape presentations, tape, video-cassette); (3) miscellaneous (buttons, pocket lab, umbrella); (4) transparencies; (5) bibliographies; and (6) curriculum materials. Sources and prices (when applicable) are…

  11. Soluble and insoluble fiber (image)

    MedlinePlus

    Dietary fiber is the part of food that is not affected by the digestive process in the body. ... of the stool. There are two types of dietary fiber, soluble and insoluble. Soluble fiber retains water and ...

  12. Docosahexaenoic acid-induced amelioration on impairment of memory learning in amyloid beta-infused rats relates to the decreases of amyloid beta and cholesterol levels in detergent-insoluble membrane fractions.

    PubMed

    Hashimoto, Michio; Hossain, Shahdat; Agdul, Haqu; Shido, Osamu

    2005-12-30

    We investigated the effects of dietary administration of docosahexaenoic acid (DHA; C22:6n-3) on the levels of amyloid beta (A beta) peptide (1-40) and cholesterol in the nonionic detergent Triton 100 x-insoluble membrane fractions (DIFs) of the cerebral cortex and, also, on learning-related memory in an animal model of Alzheimer's disease (AD) rats infused with A beta peptide (1-40) into the cerebral ventricle. The infusion increased the levels of A beta peptide and cholesterol in the DIFs concurrently with a significant increase in reference memory errors (measured by eight-arm radial-maze tasks) compared with those of vehicle rats. Conversely, the dietary administration of DHA to AD-model rats decreased the levels of A beta peptide and cholesterol in the DIFs, with the decrease being more prominent in the DHA-administered rats. Regression analysis revealed a significant positive correlation between A beta peptide and each of cholesterol, palmitic acid and stearic acid, and between the number of reference memory errors and each of cholesterol, palmitic, stearic and oleic acid; moreover, a significant negative correlation was observed between the number of reference memory errors and the molar ratio of DHA to palmitic plus stearic acid. These results suggest that DHA-induced protection of memory deficits in AD-model rats is related to the interactions of cholesterol, palmitic acid or stearic acid with A beta peptides in DIFs where DHA ameliorates these interactions.

  13. Humic and fluvic acids and organic colloidal materials in the environment

    SciTech Connect

    Gaffney, J.S.; Marley, N.A.; Clark, S.B.

    1996-04-01

    Humic substances are ubiquitous in the environment, occurring in all soils, waters, and sediments of the ecosphere. Humic substances arise from the decomposition of plant and animal tissues yet are more stable than their precursors. Their size, molecular weight, elemental composition, structure, and the number and position of functional groups vary, depending on the origin and age of the material. Humic and fulvic substances have been studied extensively for more than 200 years; however, much remains unknown regarding their structure and properties. Humic substances are those organic compounds found in the environment that cannot be classified as any other chemical class of compounds. They are traditionally defined according to their solubilities. Fulvic acids are those organic materials that are soluble in water at all pH values. Humic acids are those materials that are insoluble at acidic pH values (pH < 2) but are soluble at higher pH values. Humin is the fraction of natural organic materials that is insoluble in water at all pH values. These definitions reflect the traditional methods for separating the different fractions from the original mixture. The humic content of soils varies from 0 to almost 10%. In surface waters, the humic content, expressed as dissolved organic carbon (DOC), varies from 0.1 to 50 ppm in dark-water swamps. In ocean waters, the DOC varies from 0.5 to 1.2 ppm at the surface, and the DOC in samples from deep groundwaters varies from 0.1 to 10 ppm. In addition, about 10% of the DOC in surface waters is found in suspended matter, either as organic or organically coated inorganic particulates. Humic materials function as surfactants, with the ability to bind both hydrophobic and hydrophyllic materials, making numic and fluvic materials effective agents in transporting both organic and inorganic contaminants in the environment.

  14. Effect of insoluble-low fermentable fiber from corn-ethanol distillation origin on energy, fiber, and amino acid digestibility, hindgut degradability of fiber, and growth performance of pigs.

    PubMed

    Gutierrez, N A; Kerr, B J; Patience, J F

    2013-11-01

    Extensive use of corn coproducts in swine diets increases the concentration of dietary fiber, raising concerns on energy and nutrient digestibility and, ultimately, pig performance. A digestion trial was conducted to determine the effect of increasing levels of insoluble-low fermentable fiber from corn in the diet, using corn bran with solubles (CBS) from the corn-ethanol distillation industry, on digestibility of energy, fiber, and AA, and hindgut fermentation of fiber in diets fed to growing pigs. Fifteen growing pigs (BW=28.7 kg) arranged in a 3-period incomplete block design and fitted with a T-cannula in the distal ileum were provided 5 diets (n=9) containing either a corn-casein basal or the basal diet with 10, 20, 30, or 40% CBS. Fecal and ileal digesta samples were collected. Two subsequent 28-d growth trials determined the effects of increasing dietary fiber from CBS in 2 sets of 7 diets formulated either with declining (growing phase: 2,387 to 2,133 kcal NE/kg; finishing phase: 2,499 to 2,209 kcal NE/kg) or constant dietary NE (growing phase≈2,390 kcal NE/kg; finishing phase≈2,500 kcal NE/kg) on growth performance and apparent total tract digestibility (ATTD) of energy in 70 growing (BW=48.9 kg; n=10 per diet) and 70 finishing (BW=102.0 kg; n=10) pigs. Results indicated that increasing fiber from corn lowered (P<0.01) the apparent ileal digestibility of all indispensable amino acids except Arg, GE, DM, and CP but not NDF or total dietary fiber (TDF). Increased fiber from corn also reduced ATTD of GE, DM, CP, NDF, and TDF (P<0.01). Increasing fiber with declining diet NE lowered BW, ADG, and G:F (P<0.05) in growing and in finishing pigs. When NE was held constant, as fiber increased, BW and ADG were unaffected in growing and finishing pigs, and G:F was unaffected in finishing pigs but improved in growing pigs (P<0.05) with increasing dietary fiber. In both growing and finishing pigs, ADFI was unaffected by the increased fiber from corn, regardless of

  15. Resistance of geopolymer materials to acid attack

    SciTech Connect

    Bakharev, T

    2005-04-01

    This article presents an investigation into durability of geopolymer materials manufactured using a class F fly ash (FA) and alkaline activators when exposed to 5% solutions of acetic and sulfuric acids. The main parameters studied were the evolution of weight, compressive strength, products of degradation and microstructural changes. The degradation was studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The performance of geopolymer materials when exposed to acid solutions was superior to ordinary Portland cement (OPC) paste. However, significant degradation of strength was observed in some geopolymer materials prepared with sodium silicate and with a mixture of sodium hydroxide and potassium hydroxide as activators. The deterioration observed was connected to depolymerisation of the aluminosilicate polymers in acidic media and formation of zeolites, which in some cases lead to a significant loss of strength. The best performance was observed in the geopolymer material prepared with sodium hydroxide and cured at elevated temperature, which was attributed to a more stable cross-linked aluminosilicate polymer structure formed in this material.

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

    PubMed Central

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

    2016-01-01

    The nano- and micropatterned biosilica cell walls of diatoms are remarkable examples of biological morphogenesis and possess highly interesting material properties. Only recently has it been demonstrated that biosilica-associated organic structures with specific nanopatterns (termed insoluble organic matrices) are general components of diatom biosilica. The model diatom Thalassiosira pseudonana contains three types of insoluble organic matrices: chitin meshworks, organic microrings, and organic microplates, the latter being described in the present study for the first time. To date, little is known about the molecular composition, intracellular assembly, and biological functions of organic matrices. Here we have performed structural and functional analyses of the organic microrings and organic microplates from T. pseudonana. Proteomics analysis yielded seven proteins of unknown function (termed SiMat proteins) together with five known silica biomineralization proteins (four cingulins and one silaffin). The location of SiMat1-GFP in the insoluble organic microrings and the similarity of tyrosine- and lysine-rich functional domains identifies this protein as a new member of the cingulin protein family. Mass spectrometric analysis indicates that most of the lysine residues of cingulins and the other insoluble organic matrix proteins are post-translationally modified by short polyamine groups, which are known to enhance the silica formation activity of proteins. Studies with recombinant cingulins (rCinY2 and rCinW2) demonstrate that acidic conditions (pH 5.5) trigger the assembly of mixed cingulin aggregates that have silica formation activity. Our results suggest an important role for cingulins in the biogenesis of organic microrings and support the hypothesis that this type of insoluble organic matrix functions in biosilica morphogenesis. PMID:26710847

  17. Acidic magnetorheological finishing of infrared polycrystalline materials

    DOE PAGES

    Salzman, S.; Romanofsky, H. J.; West, G.; ...

    2016-10-12

    Here, chemical-vapor–deposited (CVD) ZnS is an example of a polycrystalline material that is difficult to polish smoothly via the magnetorheological–finishing (MRF) technique. When MRF-polished, the internal infrastructure of the material tends to manifest on the surface as millimeter-sized “pebbles,” and the surface roughness observed is considerably high. The fluid’s parameters important to developing a magnetorheological (MR) fluid that is capable of polishing CVD ZnS smoothly were previously discussed and presented. These parameters were acidic pH (~4.5) and low viscosity (~47 cP). MRF with such a unique MR fluid was shown to reduce surface artifacts in the form of pebbles; however,more » surface microroughness was still relatively high because of the absence of a polishing abrasive in the formulation. In this study, we examine the effect of two polishing abrasives—alumina and nanodiamond—on the surface finish of several CVD ZnS substrates, and on other important IR polycrystalline materials that were finished with acidic MR fluids containing these two polishing abrasives. Surface microroughness results obtained were as low as ~28 nm peak-to-valley and ~6-nm root mean square.« less

  18. Acidic magnetorheological finishing of infrared polycrystalline materials

    SciTech Connect

    Salzman, S.; Romanofsky, H. J.; West, G.; Marshall, K. L.; Jacobs, S. D.; Lambropoulos, J. C.

    2016-10-12

    Here, chemical-vapor–deposited (CVD) ZnS is an example of a polycrystalline material that is difficult to polish smoothly via the magnetorheological–finishing (MRF) technique. When MRF-polished, the internal infrastructure of the material tends to manifest on the surface as millimeter-sized “pebbles,” and the surface roughness observed is considerably high. The fluid’s parameters important to developing a magnetorheological (MR) fluid that is capable of polishing CVD ZnS smoothly were previously discussed and presented. These parameters were acidic pH (~4.5) and low viscosity (~47 cP). MRF with such a unique MR fluid was shown to reduce surface artifacts in the form of pebbles; however, surface microroughness was still relatively high because of the absence of a polishing abrasive in the formulation. In this study, we examine the effect of two polishing abrasives—alumina and nanodiamond—on the surface finish of several CVD ZnS substrates, and on other important IR polycrystalline materials that were finished with acidic MR fluids containing these two polishing abrasives. Surface microroughness results obtained were as low as ~28 nm peak-to-valley and ~6-nm root mean square.

  19. Measurement of pentane insolubles by hot soxhlet extraction

    SciTech Connect

    Choney, J.H. )

    1988-06-01

    A rapid, reliable and reproducible method for measuring pentane insoluble material in waxy lube stocks has been developed. The method uses a specially designed soxhlet apparatus in which approximately 20 to 30 g of neat waxy lube stock can be extracted using hot pentane. The duration of this test is 45 to 90 minutes. (For comparison, the ASTM method for measuring pentane insolubles requires a minimum of eight hours for sample dewaxing.) The reproducibility of the test method between two independent laboratories was determined.

  20. Components of the ether-insoluble resin glycoside-like fraction from Cuscuta chinensis.

    PubMed

    Du, X M; Kohinata, K; Kawasaki, T; Guo, Y T; Miyahara, K

    1998-07-01

    A trisaccharide and four new glycosidic acids, named cuscutic acids A-D, along with known organic acids, acetic acid, propionic acid, (2S)-2-methylbutyric acid, tiglic acid, (2R, 3 R)-nilic acid, (11S) convolvulinolic acid and (11S)-jalapinolic acid have been isolated from the alkaline hydrolysate of the ether-insoluble resin glycoside-like fraction of the seeds of Cuscuta chinensis. The compounds were characterized on the basis of chemical and physical data.

  1. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    SciTech Connect

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert

    2010-05-03

    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  2. Acid soluble platelet aggregating material isolated from human umbilical cord

    SciTech Connect

    Schneider, M.D.

    1983-12-27

    An acid soluble, pepsin sensitive platelet aggregating material is isolated from human umbilical cord tissue by extraction with dilute aqueous acid. The method of isolation is disclosed and its use to control bleeding is described. 2 figs.

  3. Sources of insoluble inclusions in stratospheric sulfate particles

    NASA Astrophysics Data System (ADS)

    Bigg, E. Keith

    2012-05-01

    Properties of aerosol collected in the stratosphere from altitudes of 20-45 km are reviewed. Removal of the soluble material from predominantly sulfate particles collected at 20 km revealed the presence of insoluble individual particles, or small groups of them, typically 40-50 nm in diameter. The size distribution of components of chain aggregates found above 35 km was almost identical, suggesting that rupture of the chains by condensing sulfuric acid, as they fell into the sulfate layer from above, was the source of the inclusions. Particles collected above 35 km on thin films of metal all showed the presence of a partially volatile liquid. On a copper surface, the liquid was stabilized, and of greater extent than the solid component. Three observations suggest that the upper stratospheric particles and their associated liquid were partly or wholly organic and derived from cometary dust too small to be heated on entering the atmosphere. These are: (1) the presence of a liquid that reacts with copper and the similarity to the behavior of particles collected on copper during a manned space flight, (2) their morphological similarity to published photographs of particles collected in the mesosphere from rockets, (3) the consistency with recent spacecraft observations of the size distribution of components sub-10 μm aggregates in cometary dust and the presence within them of carbon compounds.

  4. Plant and soil intake by organic broilers reared in tree- or grass-covered plots as determined by means of n-alkanes and of acid-insoluble ash.

    PubMed

    Jurjanz, S; Germain, K; Juin, H; Jondreville, C

    2015-05-01

    Free-range birds such as organic broilers may ingest soil and plants during exploration. The estimation of such intakes is of great interest to quantify possible nutritional supplies and also to evaluate the risk of exposure to parasites or to environmental contaminants. Marker-based techniques are now available and would allow to quantify plant and, especially, soil intake in free-range birds, and this quantification was the aim of this study. Methodologically, the proportion of plants in diet intake was determined first using a method based on n-alkanes. Subsequently, the fraction of soil in the total intake was estimated with a second marker, acid-insoluble ash. This approach was carried out to estimate ingested amounts of plants and soil for five successive flocks of organic broilers, exploring grass-covered yards or those under trees, at two time points for each yard: 51 and 64 days of age. Each factor combination (yard type×period=flock number×age) was repeated on two different yards of 750 broilers each. The birds' plant intake varied widely, especially on grass-covered yards. The proportion of plant intake was significantly higher on grass-covered plots than under trees and was also affected, but to a lesser extent, by age or flock number. The ingestion of plants would generally not exceed 11 g of DM daily, except two extreme outliers of nearly 30 g. The daily plant intake under trees tended to be lower and never exceeded 7 g of DM. The amount of ingested plants increased significantly for spring flocks. It increased slightly but significantly with age. The proportion of ingested soil was significantly higher under trees than on grass-covered yards. Dry soil intake was generally low with not more than 3 g per day. Only in adverse conditions - that is, older birds exploring yards under trees in winter - soil intake reached the extreme value of nearly 5 g. Broilers on yards under trees ingested significantly more soil than on grass-covered yards with least

  5. Insoluble and flexible silk films containing glycerol.

    PubMed

    Lu, Shenzhou; Wang, Xiaoqin; Lu, Qiang; Zhang, Xiaohui; Kluge, Jonathan A; Uppal, Neha; Omenetto, Fiorenzo; Kaplan, David L

    2010-01-11

    We directly prepared insoluble silk films by blending with glycerol and avoiding the use of organic solvents. The ability to blend a plasticizer like glycerol with a hydrophobic protein like silk and achieve stable material systems above a critical threshold of glycerol is an important new finding with importance for green chemistry approaches to new and more flexible silk-based biomaterials. The aqueous solubility, biocompatibility, and well-documented use of glycerol as a plasticizer with other biopolymers prompted its inclusion in silk fibroin solutions to assess impact on silk film behavior. Processing was performed in water rather than organic solvents to enhance the potential biocompatibility of these biomaterials. The films exhibited modified morphologies that could be controlled on the basis of the blend composition and also exhibited altered mechanical properties, such as improved elongation at break, when compared with pure silk fibroin films. Mechanistically, glycerol appears to replace water in silk fibroin chain hydration, resulting in the initial stabilization of helical structures in the films, as opposed to random coil or beta-sheet structures. The use of glycerol in combination with silk fibroin in materials processing expands the functional features attainable with this fibrous protein, and in particular, in the formation of more flexible films with potential utility in a range of biomaterial and device applications.

  6. Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

    DOEpatents

    Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher; Dai, Sheng

    2016-06-07

    An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.

  7. Alkaline phosphatase of Physarum polycephalum is insoluble.

    PubMed

    Furuhashi, Kiyoshi

    2008-02-01

    The plasmodia of Physarum polycephalum grow as multinucleated cells in the presence of sufficient humidity and nutriment. Under non-illuminating conditions, stresses such as low temperature or high concentrations of salts transform the plasmodia into spherules whereas dehydration induces sclerotization. Some phosphatases including protein phosphatase and acid phosphatase have been purified from the plasmodia, but alkaline phosphatase remains to be elucidated. Phosphatase of the plasmodia, spherules and sclerotia was visualized by electrophoresis gel-staining assay using 5-bromo-4-chloro-3-indolyl phosphate. Insoluble fractions of the sclerotia were abundant in phosphatase activity. The phosphatase which was extracted by nonionic detergent was subjected to column chromatography and preparative electrophoresis. Purified phosphatase showed the highest activity at pH 8.8, indicating that this enzyme belongs to alkaline phosphatase. The apparent molecular mass from sodium dodecyl sulfate-polyacrylamide gel electrophoresis under non-reducing condition was estimated to be 100 kDa whereas that under reducing was 105 kDa. An amount of 1% sodium dodecyl sulfate or 0.5 M NaCl had no effects on the activity although the phosphatase showed heat instability, Mg(2+)-dependency and sensitivity to 2-glycerophosphate or NaF. The extracting conditions and enzymatic properties suggest that this alkaline phosphatase which is in a membrane-bound form plays important roles in phosphate metabolism.

  8. Acid Rain Materials for Classroom Use.

    ERIC Educational Resources Information Center

    Factor, Lance; Kooser, Robert G.

    This booklet contains three separate papers suitable for use in an advanced high school or college chemistry course. The first paper provides background information on acids and bases. The second paper provides additional background information, focusing on certain aspects of atmospheric chemistry as it relates to the acid rain problem. An attempt…

  9. Production of insoluble exopolysaccharide of Agrobacterium sp. (ATCC 31749 and IFO 13140).

    PubMed

    Portilho, Márcia; Matioli, Graciette; Zanin, Gisella Maria; de Moraes, Flávio Faria; Scamparini, Adilma Regina Pippa

    2006-01-01

    Agrobacterium isolated from soil samples produced two extracellular polysaccharides: succinoglycan, an acidic soluble polymer, and curdlan gum, a neutral, insoluble polymer. Maize glucose, cassava glucose, and maize maltose were used in fermentation medium to produce insoluble polysaccharide. Two Agrobacterium sp. strains which were used (ATCC 31749 and IFO 13140) in the production of insoluble exopolysaccharide presented equal or superior yields compared to the literature. The strain ATCC 31749 yielded better production when using maize maltose, whose yield was 85%, whereas strain IFO 13140 produced more when fed maize glucose, producing a yield of 50% (on reducing sugars).

  10. Production of insoluble exopolysaccharide of Agrobacterium sp. (ATCC 31749 and IFO 13140).

    PubMed

    Portilho, Márcia; Matioli, Graciette; Zanin, Gisella Maria; de Moraes, Flávio Faria; Scamparini, Adilma Regina Pippa

    2006-03-01

    Agrobacterium isolated from soil samples produced two extracellular polysaccharides: succinoglycan, an acidic soluble polymer, and curdlan gum, a neutral, insoluble polymer. Maize glucose, cassava glucose, and maize maltose were used in fermentation medium to produce insoluble polysaccharide. Two Agrobacterium sp. strains which were used (ATCC 31749 and IFO 13140) in the production of insoluble exopolysaccharide presented equal or superior yields compared to the literature. The strain ATCC 31749 yielded better production when using maize maltose, whose yield was 85%, whereas strain IFO 13140 produced more when fed maize glucose, producing a yield of 50% (on reducing sugars).

  11. Peptide nucleic acids in materials science

    PubMed Central

    Bonifazi, Davide; Carloni, Laure-Elie; Corvaglia, Valentina; Delforge, Arnaud

    2012-01-01

    This review highlights the recent methods to prepare PNA-based materials through a combination of self-assembly and self-organization processes. The use of these methods allows easy and versatile preparation of structured hybrid materials showing specific recognition properties and unique physicochemical properties at the nano- and micro-scale levels displaying potential applications in several directions, ranging from sensors and microarrays to nanostructured devices for biochips. PMID:22925824

  12. Materials characterization of phosphoric acid fuel cell system

    NASA Technical Reports Server (NTRS)

    Venkatesh, Srinivasan

    1986-01-01

    The component materials used in the fabrication of phosphoric acid fuel cells (PAFC) must have mechanical, chemical, and electrochemical stability to withstand the moderately high temperature (200 C) and pressure (500 kPa) and highly oxidizing nature of phosphoric acid. This study discusses the chemical and structural stability, performance and corrosion data on certain catalysts, catalyst supports, and electrode support materials used in PAFC applications.

  13. Fundamental Study on Enhancement of Liquid-Liquid Direct Contact Heat Transfer of Descending Water Insoluble High Density Liquid Droplets in a Heat Source Water Layer by Using Wire Mesh as Dispersion Material

    NASA Astrophysics Data System (ADS)

    Inaba, Hideo; Horibe, Akihiko; Yokoyama, Naoki; Haruki, Naoto

    This paper has dealt with liquid-liquid direct contact heat transfer characteristics by means of water insoluble heat transfer medium. In the present study, Perfluorocarbon(PFC, density of 1830kg/m3)was injected from above into a hot water layer, which was mounted by stainless steel wire net in order to make PFC droplets finer. The measuring result of the drop let diameter revealed that the droplet size distribution exerted an influence on the temperature effectiveness between PFC droplets and the hot water layer. It was observed that PFC droplets were dispersed by collision with stainless steel wire nets during falling in the hot water layer. Finally correlations equations of the temperature effectiveness and average diameter of PFC droplets had been derived as a function of some parameters.

  14. Phosphoric acid, nitric acid, and hydrogen peroxide digestion of soil and plant materials for selenium determination

    SciTech Connect

    Dong, A.; Rendig, V.V.; Burau, R.G.; Besga, G.S.

    1987-11-15

    A mixture of phosphoric acid, nitric acid, and hydrogen peroxide has been proposed as an alternative to the use of the nitric/perchloric acid mixture to digest biological fluids to determine their selenium (Se) content. The purpose of the studies reported here was to test the applicability of this digestion method for the determination of Se in soil and plant materials.

  15. Water-insoluble Silk Films with Silk I Structure

    SciTech Connect

    Lu, Q.; Hu, X; Wang, X; Kluge, J; Lu, S; Cebe, P; Kaplan, D

    2010-01-01

    Water-insoluble regenerated silk materials are normally produced by increasing the {beta}-sheet content (silk II). In the present study water-insoluble silk films were prepared by controlling the very slow drying of Bombyx mori silk solutions, resulting in the formation of stable films with a predominant silk I instead of silk II structure. Wide angle X-ray scattering indicated that the silk films stabilized by slow drying were mainly composed of silk I rather than silk II, while water- and methanol-annealed silk films had a higher silk II content. The silk films prepared by slow drying had a globule-like structure at the core surrounded by nano-filaments. The core region was composed of silk I and silk II, surrounded by hydrophilic nano-filaments containing random turns and {alpha}-helix secondary structures. The insoluble silk films prepared by slow drying had unique thermal, mechanical and degradative properties. Differential scanning calorimetry results revealed that silk I crystals had stable thermal properties up to 250 C, without crystallization above the T{sub g}, but degraded at lower temperatures than silk II structure. Compared with water- and methanol-annealed films the films prepared by slow drying had better mechanical ductility and were more rapidly enzymatically degraded, reflecting the differences in secondary structure achieved via differences in post processing of the cast silk films. Importantly, the silk I structure, a key intermediate secondary structure for the formation of mechanically robust natural silk fibers, was successfully generated by the present approach of very slow drying, mimicking the natural process. The results also point to a new mode of generating new types of silk biomaterials with enhanced mechanical properties and increased degradation rates, while maintaining water insolubility, along with a low {beta}-sheet content.

  16. Endoplasmic Reticulum Bodies: Solving the Insoluble

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant cells produce and accumulate insoluble triglycerides, proteins and rubber that are assembled into inert ER-derived organelles broadly termed ER-bodies. ER-bodies appear to originate from tubular ER domains that are maintained by cytoskeletal interactions and integral ER proteins. ER-bodies seq...

  17. Rapid and repeatable redox cycling of an insoluble dietary antioxidant: electrochemical analysis.

    PubMed

    Lee, Morgan E; Kim, Eunkyoung; Liu, Yi; March, John C; Bentley, William E; Payne, Gregory F

    2014-10-08

    There are many unresolved questions concerning the health benefits of dietary antioxidants due in part to the complexity of the materials and mechanisms of action. We applied a new electrochemical method and report new observations for one of the richest sources of dietary antioxidants. We observed that the insoluble fraction of clove is redox-active and can be rapidly and repeatedly switched between oxidized and reduced states. Also, the radical scavenging antioxidant properties of insoluble clove are largely independent of this reversible redox activity, which is similar to observations made with the natural phenolic melanin. In contrast to melanin, insoluble clove was observed to have little pro-oxidant activity (as measured by H2O2 generation) irrelevant to whether it was poised in an oxidized or reduced state. These results suggest that dietary antioxidants, even when insoluble and nonabsorbed, can undergo important redox interactions in the intestinal tract.

  18. Surface-functionalized diatom microcapsules for drug delivery of water-insoluble drugs.

    PubMed

    Aw, Moom Sinn; Bariana, Manpreet; Yu, Yang; Addai-Mensah, Jonas; Losic, Dusan

    2013-08-01

    Naturally available and biocompatible materials are potential substitutes for synthetic mesoporous materials as suitable drug carriers for the development of cost-effective drug delivery systems. This work investigates the application of a porous silica material derived from diatoms, also known as diatomaceous earth. The aim is to explore the surface functionalization of diatom microcapsules and their impact on the drug loading and release characteristics of water-insoluble drugs. Indomethacin was used as the model for poorly soluble drug. The surface modification on diatoms was performed with two organosilanes; 3-aminopropyltriethoxy silane and N-(3-(trimethoxysilyl) propyl) ethylene diamine and phosphonic acids (2-carboxyethyl-phosphonic acid and 16-phosphono-hexadecanoic acid) providing organic surface hydrophilic and hydrophobic properties. Extensive characterizations using scanning electron microscopy, X-ray photoelectron spectroscopy and differential scanning calorimetry was performed to confirm covalent grafting of monolayer aminosilane and phosphonic acid on the diatom surfaces. Differences in loading capacity of diatoms (15-24%) and release time (6-15 days) were observed which is due to the presence of different functional groups on the surface. It was found that 2-carboxyethyl-phosphonic acid, 3-aminopropyltriethoxy silane and N-(3-(trimethoxysilyl) propyl) ethylene diamine render diatom surfaces hydrophilic, due to polar carboxyl functional group (COOH) and active amine species (NH and NH2) that favor drug adsorption; better encapsulation efficiency and prolonged release of drugs, over the hydrophobic surface created by 16-phosphono-hexadecanoic acid. This work demonstrates diatom porous silica as a promising drug carrier, with possibility to further improve their performances by tailoring their surface functionalities to achieve the required drug loading and release characteristics for different therapeutic conditions.

  19. Extraterrestrial material analysis: loss of amino acids during liquid-phase acid hydrolysis

    NASA Astrophysics Data System (ADS)

    Buch, Arnaud; Brault, Amaury; Szopa, Cyril; Freissinet, Caroline

    2015-04-01

    Searching for building blocks of life in extraterrestrial material is a way to learn more about how life could have appeared on Earth. With this aim, liquid-phase acid hydrolysis has been used, since at least 1970 , in order to extract amino acids and other organic molecules from extraterrestrial materials (e.g. meteorites, lunar fines) or Earth analogues (e.g. Atacama desert soil). This procedure involves drastic conditions such as heating samples in 6N HCl for 24 h, either under inert atmosphere/vacuum, or air. Analysis of the hydrolyzed part of the sample should give its total (free plus bound) amino acid content. The present work deals with the influence of the 6N HCl hydrolysis on amino acid degradation. Our experiments have been performed on a standard solution of 17 amino acids. After liquid-phase acid hydrolysis (6N HCl) under argon atmosphere (24 h at 100°C), the liquid phase was evaporated and the dry residue was derivatized with N-Methyl-N-(t-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF), followed by gas chromatography-mass spectrometry analysis. After comparison with derivatized amino acids from the standard solution, a significant reduction of the chromatographic peak areas was observed for most of the amino acids after liquid-phase acid hydrolysis. Furthermore, the same loss pattern was observed when the amino acids were exposed to cold 6N HCl for a short amount of time. The least affected amino acid, i.e. glycine, was found to be 73,93% percent less abundant compared to the non-hydrolyzed standard, while the most affected, i.e. histidine, was not found in the chromatograms after hydrolysis. Our experiments thereby indicate that liquid-phase acid hydrolysis, even under inert atmosphere, leads to a partial or total loss of all of the 17 amino acids present in the standard solution, and that a quick cold contact with 6N HCl is sufficient to lead to a loss of amino acids. Therefore, in the literature, the reported increase

  20. 76 FR 33243 - Sulfanilic Acid From India; Final Results of Expedited Sunset Review of Countervailing Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... include technical (or crude) sulfanilic acid, refined (or purified) sulfanilic acid and sodium salt of sulfanilic acid (sodium sulfanilate). Sulfanilic acid is a synthetic organic chemical produced from the....5 percent maximum aniline, and 0.25 percent maximum alkali insoluble materials. Sodium salt...

  1. Graphdiyne as a promising material for detecting amino acids

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Gao, Pengfei; Guo, Lei; Zhang, Shengli

    2015-11-01

    The adsorption of glycine, glutamic acid, histidine and phenylalanine on single-layer graphdiyne/ graphene is investigated by ab initio calculations. The results show that for each amino acid molecule, the adsorption energy on graphdiyne is larger than the adsorption energy on graphene and dispersion interactions predominate in the adsorption. Molecular dynamics simulations reveal that at room temperature the amino acid molecules keep migrating and rotating on graphdiyne surface and induce fluctuation in graphdiyne bandgap. Additionally, the photon absorption spectra of graphdiyne-amino-acid systems are investigated. We uncover that the presence of amino acid molecules makes the photon absorption peaks of graphdiyne significantly depressed and shifted. Finally, quantum electronic transport properties of graphdiyne-amino-acid systems are compared with the transport properties of pure graphdiyne. We reveal that the amino acid molecules induce distinct changes in the electronic conductivity of graphdiyne. The results in this paper reveal that graphdiyne is a promising two-dimensional material for sensitively detecting amino acids and may potentially be used in biosensors.

  2. 21 CFR 184.1372 - Insoluble glucose isomerase enzyme preparations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Insoluble glucose isomerase enzyme preparations... Substances Affirmed as GRAS § 184.1372 Insoluble glucose isomerase enzyme preparations. (a) Insoluble glucose isomerase enzyme preparations are used in the production of high fructose corn syrup described in §...

  3. [Determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS].

    PubMed

    Hu, Zhao-chu; Gao, Shan; Liu, Xiao-ming; Yuan, Hong-lin; Liu, Ye; Diwu, Chun-rong

    2007-12-01

    The authors studied in detail the memory effect of Bi, Sb, As and Te in ICP-MS. The produced memory effects of these element were in the order of Bi>Sb>Te>As. Bi was seriously adsorbed by the polypropylene sample storing bottle and the sample introduction system in the low nitric acid medium (0.01%-1% HNO3). The washout effect of 0.1% HF was found to be better than those of 6% HNO3 and 0.1% HClO4. Under the given experiment conditions, the instrumental limit of detection was 0.001 and 0.0001 ng x mL(-1) for Sb and Bi, respectively. The authors report the determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS (including AGV-2, BHVO-2, BCR-2, etc.). Most of the results were found to be in reasonable agreement with the reported values in the literature. The authors' determined values of Sb for GSR-1 (granite; 0.30 microg x g(-1)) and JP-1 (peridotite; 0.045 microg x g(-1)) are obviously higher than those reported values. This is attributed to the efficient pressurized acid digestion, which is generally much more efficient than conventional wet digestions for insoluble minerals.

  4. Enzymatic saccharification of dilute acid pretreated eucalyptus chips for fermentable sugar production.

    PubMed

    Wei, Weiqi; Wu, Shubin; Liu, Liguo

    2012-04-01

    Dilute sulfuric acid was used to pretreat eucalyptus chips prior to enzymatic hydrolysis. After both pretreatment and enzymatic hydrolysis processes. Attention is paid to sugar recovery. The maximum total sugars yield (combined xylose and glucose, 47.69g/100g raw material, representing 82% of total sugars in the eucalyptus biomass) was obtained at 160°C, 0.75% acid concentration and 10min residence time, which is consider to be the best reasonable conditions for the dilute acid pretreatment of eucalyptus, corresponding concentrations of acetic acid, HMF, and furfural in the prehydrolysate were about 2.01g/L, 0.13g/L and 1.37g/L, respectively. Under this optimal pretreatment condition, the acid-insoluble lignin recovery in the insoluble solid resulting from enzymatic hydrolysis, was 22.7g/100g raw material, representing 80% of acid-insoluble lignin in the eucalyptus biomass.

  5. Gradual surface degradation of restorative materials by acidic agents.

    PubMed

    Hengtrakool, Chanothai; Kukiattrakoon, Boonlert; Kedjarune-Leggat, Ureporn

    2011-01-01

    The aim of this study was to investigate the effect of acidic agents on surface roughness and characteristics of four restorative materials. Fifty-two discs were created from each restorative material: metal-reinforced glass ionomer cement (Ketac-S), resin-modified glass ionomer cement (Fuji II LC), resin composite (Filtek Z250), and amalgam (Valiant-PhD); each disc was 12 mm in diameter and 2.5 mm thick. The specimens were divided into four subgroups (n=13) and immersed for 168 hours in four storage media: deionized water (control); citrate buffer solution; green mango juice; and pineapple juice. Surface roughness measurements were performed with a profilometer, both before and after storage media immersion. Surface characteristics were examined using scanning electron microscopy (SEM). Statistical significance among each group was analyzed using two-way repeated ANOVA and Tukey's tests. Ketac-S demonstrated the highest roughness changes after immersion in acidic agents (p<0.05), followed by Fuji II LC. Valiant-PhD and Filtek Z250 illustrated some minor changes over 168 hours. The mango juice produced the greatest degradation effect of all materials tested (p<0.05). SEM photographs demonstrated gradual surface changes of all materials tested after immersions. Of the materials evaluated, amalgam and resin composite may be the most suitable for restorations for patients with tooth surface loss.

  6. Particle size reduction effectively enhances the cholesterol-lowering activities of carrot insoluble fiber and cellulose.

    PubMed

    Chou, Sze-Yuan; Chien, Po-Jung; Chau, Chi-Fai

    2008-11-26

    This study investigated and compared the effects of particle size reduction on the cholesterol-lowering activities of carrot insoluble fiber-rich fraction (IFF) and plant cellulose. Our results demonstrated that micronization treatment effectively pulverized the particle sizes of these insoluble fibers to different microsizes. Feeding the micronized insoluble fibers, particularly the micronized carrot IFF, significantly (p < 0.05) improved their abilities in lowering the concentrations of serum triglyceride (18.6-20.0%), serum total cholesterol (15.5-19.5%), and liver lipids (16.7-20.3%) to different extents by means of enhancing (p < 0.05) the excretion of lipids (124-131%), cholesterol (120-135%), and bile acids (130-141%) in feces. These results suggested that particle size was one of the crucial factors in affecting the characteristics and physiological functions of insoluble fibers. Therefore, particle size reduction by micronization might offer the industry an opportunity to improve the physiological functions of insoluble fibers, particularly the carrot IFF, in health food applications.

  7. Human urine certified reference material CZ 6009: creatinine, styrene metabolites (mandelic acid and phenylglyoxylic acid).

    PubMed

    Sperlingová, I; Dabrowská, L; Stránský, V; Kucera, J; Tichý, M

    2004-03-01

    The reference material was prepared by freeze-drying pooled urine samples obtained from healthy persons occupationally exposed to styrene. The concentrations of mandelic acid (MA), phenylglyoxylic acid (PGA), and hippuric acid (HA) in urine were determined by three modes of high-performance liquid chromatography (HPLC). For isochronous stability testing the urinary mandelic acid and phenylglyoxylic acid concentrations were followed over a 24-month period for a preliminary batch by use of HPLC. No changes of the concentration values were found. The creatinine concentration was stable for more than five years. Standard Reference Material NIST 914a Creatinine was used for traceability purposes for creatinine. Pure chemicals MA and PGA were used for traceability purposes. Control material ClinChek-Urine Control (Recipe) was analyzed simultaneously. The mean values of MA and PGA compare well with the means and fall within the control range of control samples. Results from homogeneity, stability, and traceability testing were evaluated using the statistical program ANOVA. The certified values and their uncertainties were evaluated from the results of interlaboratory comparisons, and homogeneity and stability tests. The values are unweighed arithmetical averages of accepted results and their uncertainties are combined uncertainties (coverage factor=1).

  8. Identification of "insoluble" red dyewoods by high performance liquid chromatography-photodiode array detection (HPLC-PDA) fingerprinting.

    PubMed

    Surowiec, Izabella; Nowik, Witold; Trojanowicz, Marek

    2004-02-01

    The paper describes a high performance liquid chromatography-UV/Vis spectrometry detection analytical approach to the identification of some redwood species of historical importance in textile dyeing. The group of extracted dyestuffs considered as "insoluble" because of their non-aqueous or alkaline extraction conditions is present in the wood of the Pterocarpus family and Baphia nitida species. First, the crude extracts of tinctorial and related species and their chromatographic fingerprints were studied. This part of work shows that some species not yet mentioned in the literature have potential dyeing properties. Subsequent experiments performed on the redwood cargo of a 200-year-old archaeological shipwreck allowed identification of the water-logged wood species. Furthermore, the different methods of dyestuff extraction used for dyeing according to traditional recipes and their impact on analytical results were studied. They show that standard recovery obtained by acid hydrolysis of dyestuff from dyed yarns is inadequate. Hence, alternative solvent-based procedures were proposed. The identification of species in textile threads then becomes possible. The applied approach was validated by analysis of dyed reference yarns with some indications of crude material extraction mode. The employed method of analysis seems to be useful for "insoluble" wood species identification in cultural heritage artifacts as well as for phytochemical purposes, despite the fact that very few detected color compounds were chemically identified.

  9. Effects of acid fog and dew on materials. Final report

    SciTech Connect

    Mansfeld, F.; Henry, R.; Vijayakumar, R.

    1989-10-01

    Field exposure tests have been carried out in order to separate the effects of acidic fog on materials damage from those caused by rain, dew and natural weathering. The test sites were McKittrick and Visalia in the Central Valley and West Casitas Pass in Ventura County. The field tests have been supported by laboratory tests in which materials damage has been determined during exposure to carefully controlled fog water chemistry. Analysis of the field exposure results for galvanized steel and the paint samples shows that the corrosivity of the atmosphere at the three test sites have been very low. The result is confirmed by the ACRM data which show very low corrosion activity. Since corrosion rates were so low approaching those for natural weathering, it was not possible to determine the effects of acidic fog. Based on the aerometric data and the observed corrosion behavior, it is doubtful that acidic fog conditions prevailed for significant times during the exposure period of 1/87 - 3/88 at Visalia and McKittrick. The results of the laboratory tests show that exposure to HNO3 at low pH and to high pollutant concentration increased the corrosion rate of galvanized steel to over 10 micro m/year. Exposure to HNO3 caused serious corrosion damage to anodized aluminum and the paint.

  10. Sono-assisted extraction of alcohol-insoluble extract from Althaea rosea: purification and chemical analysis.

    PubMed

    Eskandari, Meghdad; Samavati, Vahid

    2015-01-01

    A Box-Behnken design (BBD) was used to evaluate the effects of ultrasonic power, extraction time, extraction temperature, and water to raw material ratio on extraction yield of alcohol-insoluble polysaccharide of Althaea rosea leaf (ARLP). Purification was carried out by dialysis method. Chemical analysis of ARLP revealed contained 12.69 ± 0.48% moisture, 79.33 ± 0.51% total sugar, 3.82 ± 0.21% protein, 11.25 ± 0.37% uronic acid and 3.77 ± 0.15% ash. The response surface methodology (RSM) showed that the significant quadratic regression equation with high R(2) (=0.9997) was successfully fitted for extraction yield of ARLP as function of independent variables. The overall optimum region was found to be at the combined level of ultrasonic power 91.85 W, extraction time 29.94 min, extraction temperature 89.78 °C, and the ratio of water to raw material 28.77 (mL/g). At this optimum point, extraction yield of ARLP was 19.47 ± 0.41%. No significant (p>0.05) difference was found between the actual and predicted (19.30 ± 0.075%) values. The results demonstrated that ARLP had strong scavenging activities on DPPH and hydroxyl radicals.

  11. EDTA-insoluble, calcium-binding proteoglycan in bovine bone

    NASA Technical Reports Server (NTRS)

    Hashimoto, Y.; Lester, G. E.; Caterson, B.; Yamauchi, M.

    1995-01-01

    A calcium ion precipitable, trypsin-generated proteoglycan fragment has been isolated from the demineralized, EDTA-insoluble matrices of bone. The demineralized matrix was completely digested with trypsin, increasing concentrations of CaCl2 were added to the supernatant, and the resulting precipitates were analyzed. The amount of precipitate gradually increased with higher concentrations of calcium and was reversibly solubilized by EDTA. After molecular sieve and anion exchange chromatography, a proteoglycan-containing peak was obtained. Immunochemical analysis showed that this peak contained chondroitin 4-sulfate and possibly keratan sulfate. Amino acid analysis showed that this proteoglycan contained high amounts of aspartic acid/asparagine (Asx), serine (Ser), glutamic acid/glutamine (Glx), proline (Pro), and glycine (Gly); however, it contained little leucine (Leu) which suggests that it is not a member of the leucine-rich small proteoglycan family. In addition, significant amounts of phosphoserine (P-Ser) and hydroxyproline (Hyp) were identified in hydrolysates of this fraction. A single band (M(r) 59 kDa) was obtained on SDS-PAGE that stained with Stains-all but not with Coomassie Brilliant Blue R-250. If bone powder was trypsinized prior to demineralization, this proteoglycan-containing fraction was not liberated. Collectively, these results indicate that a proteoglycan occurs in the demineralized matrix that is precipitated with CaCl2 and is closely associated with both mineral and collagen matrices. Such a molecule might facilitate the structural network for the induction of mineralization in bone.

  12. Effects of the insoluble fiber derived from Passiflora edulis seed on plasma and hepatic lipids and fecal output.

    PubMed

    Chau, Chi-Fai; Huang, Ya-Ling

    2005-08-01

    The influence of the insoluble fiber-rich fraction (FRF) prepared from defatted Passiflora edulis seed, a potential fiber source, on plasma and hepatic lipids and fecal output were investigated in hamsters fed a hypercholesterolemic diet containing 5% insoluble FRF. The results showed that the consumption of insoluble FRF diet relative to cellulose diet could effectively (P < 0.05) decrease the levels of serum triglyceride, serum total cholesterol, and liver cholesterol, and increase (P < 0.05) the levels of total lipids, cholesterol, and bile acids in feces. The consumption of insoluble FRF also increased (P < 0.05) the fecal bulk and moisture. The marked cholesterol- and lipid-lowering effects of insoluble FRF might be partly attributed to its ability to enhance the excretion of lipids and bile acids via feces. Our results suggested that insoluble FRF could be a potential hypocholesterolemic ingredient for fiber-rich functional foods, but some further researches in humans may be needed to confirm its benefits.

  13. Relationship of Enhanced Butyrate Production by Colonic Butyrate-Producing Bacteria to Immunomodulatory Effects in Normal Mice Fed an Insoluble Fraction of Brassica rapa L.

    PubMed

    Tanaka, Sachi; Yamamoto, Kana; Yamada, Kazuki; Furuya, Kanon; Uyeno, Yutaka

    2016-05-01

    This study was performed to determine the effects of feeding a fiber-rich fraction of Brassica vegetables on the immune response through changes in enteric bacteria and short-chain fatty acid (SCFA) production in normal mice. The boiled-water-insoluble fraction of Brassica rapa L. (nozawana), which consists mainly of dietary fiber, was chosen as a test material. A total of 31 male C57BL/6J mice were divided into two groups and housed in a specific-pathogen-free facility. The animals were fed either a control diet or the control diet plus the insoluble B. rapa L. fraction for 2 weeks and sacrificed to determine microbiological and SCFA profiles in lower-gut samples and immunological molecules. rRNA-based quantification indicated that the relative population of Bacteroidetes was markedly lower in the colon samples of the insoluble B. rapa L. fraction-fed group than that in the controls. Populations of the Eubacterium rectale group and Faecalibacterium prausnitzii, both of which are representative butyrate-producing bacteria, doubled after 2 weeks of fraction intake, accompanying a marginal increase in the proportion of colonic butyrate. In addition, feeding with the fraction significantly increased levels of the anti-inflammatory cytokine interleukin-10 (IL-10) and tended to increase splenic regulatory T cell numbers but significantly reduced the population of cells expressing activation markers. We demonstrated that inclusion of the boiled-water-insoluble fraction of B. rapa L. can alter the composition of the gut microbiota to decrease the numbers of Bacteroidetes and to increase the numbers of butyrate-producing bacteria, either of which may be involved in the observed shift in the production of splenic IL-10.

  14. Effect of biosynthetic manipulation of heme on insolubility of Vitreoscilla hemoglobin in Escherichia coli

    SciTech Connect

    Hart, R.A.; Kallio, P.T.; Bailey, J.E.

    1994-07-01

    Vitreoscilla hemoglobulin (VHb) is accumulated at high levels in both soluble and insoluble forms when expressed from its native promoter on a pUC19-derived plasmid in Escherichia coli. Examination by atomic absorption spectroscopy and electron paramagnetic resonance spectroscopy revealed that the insoluble form uniformly lacks the heme prosthetic group (apoVHb). The purified soluble form contains heme (holoVHb) and is spectroscopically indistinguishable from holoVHb produced by Vitreoscilla cells. This observation suggested that a relationship may exist between the insolubility of apoVHb and biosynthesis of heme. To examine this possibility, a series of experiments were conducted to chemically and genetically manipulate the formation and conversion of 5-aminolevulinic acid (ALA), a key intermediate in heme biosynthesis. Chemical perturbations involved supplementing the growth medium with the intermediate ALA and the competitive inhibitor levulinic acid which freely cross the cell barrier. Genetic manipulations involved amplifying the gene dosage for the enzymes ALA synthase and ALA dehydratase. Results from both levulinic acid and ALA supplementations indicate that the level of soluble holoVHb correlates with the heme level but that the level of insoluble apoVHb does not. The ratio of soluble to insoluble VHb also does not correlate with the level of total VHb accumulated. The effect of amplifying ALA synthase and ALA dehydratase gene dosage is complex and may involve secondary factors. Results indicate that the rate-limiting step of heme biosynthesis in cells overproducing VHb does not lie at ALA synthesis, as it reportedly does in wild-type E. coli. 26 refs., 6 figs., 1 tab.

  15. Immobilization of EAFD heavy metals using acidic materials.

    PubMed

    Mitrakas, Manassis G; Sikalidis, Constantinos A; Karamanli, Theoktisti P

    2007-03-01

    This study was undertaken to determine the chemical and leaching characteristics of the Electric Arc Furnace Dust (EAFD) generated by a Greek plant and to investigate various acidic materials efficiency on the EAFD stabilization. In order to investigate how [OH(-)] neutralization influences EAFD heavy metals leachability, Na HCO3(-), HNO3 and H3PO4 were used as acidic materials. The concentration of Pb in leachate was found between 40 and 3.7 x 10(3) mg Pb/kg of EAFD, exceeding in all EAFD samples the maximum acceptable limit (MAL) 25 mg/kg for landfill disposal. Neutralization of [OH(-)] with HCO3(-) decreased Pb concentration in leachate at 350 mg Pb/kg of EAFD, while excess over a stoichiometry in HCO3(-) addition increased leachability of Pb, Cd, Cr, Cu as well as F. Using HNO3 as an acidic material decreased leachability of almost all the parameters concerning the EC directive 33/19-01-2003 in a pH value up to 7.2, in exception of Zn. Zinc leachability showed a U shape curve as a function of pH value. The concentration of Zn was minimized in a concentration lower than 1 mg Zn/kg EAFD in a pH range 10.5 to 9 and exceeded the MAL 90 mg/kg at a pH value 7.2. However, the major disadvantage of HNO3 was proved to be its leachability, since NO3(-) concentration in leachate was equal to HNO3 dose. H3PO4 was found the most promising acidic material for the chemical immobilization of heavy metals, since it decreased their leachability in a concentration significantly lower than MAL at a pH value up to 7.1. Finally, the concentration of Cl(-) ranged between 18 and 33 x 10(3) mg Cl(-)/kg EAFD exceeding in all EAFD samples the MAL 17 x 10(3) mg/kg. This high concentration of Cl(-) is attributed to the scrap and it could be reduced only by modification of its composition.

  16. DEVELOPMENT OF AN INSOLUBLE SALT SIMULANT TO SUPPORT ENHANCED CHEMICAL CLEANING TESTS

    SciTech Connect

    Eibling, R

    2008-05-23

    The closure process for high level waste tanks at the Savannah River Site will require dissolution of the crystallized salts that are currently stored in many of the tanks. The insoluble residue from salt dissolution is planned to be removed by an Enhanced Chemical Cleaning (ECC) process. Development of a chemical cleaning process requires an insoluble salt simulant to support evaluation tests of different cleaning methods. The Process Science and Engineering section of SRNL has been asked to develop an insoluble salt simulant for use in testing potential ECC processes (HLE-TTR-2007-017). An insoluble salt simulant has been developed based upon the residues from salt dissolution of saltcake core samples from Tank 28F. The simulant was developed for use in testing SRS waste tank chemical cleaning methods. Based on the results of the simulant development process, the following observations were developed: (1) A composition based on the presence of 10.35 grams oxalate and 4.68 grams carbonate per 100 grams solids produces a sufficiently insoluble solids simulant. (2) Aluminum observed in the solids remaining from actual waste salt dissolution tests is probably precipitated from sodium aluminate due to the low hydroxide content of the saltcake. (3) In-situ generation of aluminum hydroxide (by use of aluminate as the Al source) appears to trap additional salts in the simulant in a manner similar to that expected for actual waste samples. (4) Alternative compositions are possible with higher oxalate levels and lower carbonate levels. (5) The maximum oxalate level is limited by the required Na content of the insoluble solids. (6) Periodic mixing may help to limit crystal growth in this type of salt simulant. (7) Long term storage of an insoluble salt simulant is likely to produce a material that can not be easily removed from the storage container. Production of a relatively fresh simulant is best if pumping the simulant is necessary for testing purposes. The insoluble

  17. 21 CFR 866.5910 - Quality control material for cystic fibrosis nucleic acid assays.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... nucleic acid assays. 866.5910 Section 866.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Test Systems § 866.5910 Quality control material for cystic fibrosis nucleic acid assays. (a) Identification. Quality control material for cystic fibrosis nucleic acid assays. A quality control material...

  18. 21 CFR 866.5910 - Quality control material for cystic fibrosis nucleic acid assays.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... nucleic acid assays. 866.5910 Section 866.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Test Systems § 866.5910 Quality control material for cystic fibrosis nucleic acid assays. (a) Identification. Quality control material for cystic fibrosis nucleic acid assays. A quality control material...

  19. 21 CFR 866.5910 - Quality control material for cystic fibrosis nucleic acid assays.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... nucleic acid assays. 866.5910 Section 866.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Test Systems § 866.5910 Quality control material for cystic fibrosis nucleic acid assays. (a) Identification. Quality control material for cystic fibrosis nucleic acid assays. A quality control material...

  20. 21 CFR 866.5910 - Quality control material for cystic fibrosis nucleic acid assays.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... nucleic acid assays. 866.5910 Section 866.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Test Systems § 866.5910 Quality control material for cystic fibrosis nucleic acid assays. (a) Identification. Quality control material for cystic fibrosis nucleic acid assays. A quality control material...

  1. 21 CFR 866.5910 - Quality control material for cystic fibrosis nucleic acid assays.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... nucleic acid assays. 866.5910 Section 866.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Test Systems § 866.5910 Quality control material for cystic fibrosis nucleic acid assays. (a) Identification. Quality control material for cystic fibrosis nucleic acid assays. A quality control material...

  2. 21 CFR 184.1372 - Insoluble glucose isomerase enzyme preparations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Insoluble glucose isomerase enzyme preparations... enzyme preparations. (a) Insoluble glucose isomerase enzyme preparations are used in the production of... additional requirements for enzyme preparations in the Food Chemicals Codex, 3d Ed. (1981), p. 107, which...

  3. 21 CFR 184.1372 - Insoluble glucose isomerase enzyme preparations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Insoluble glucose isomerase enzyme preparations... enzyme preparations. (a) Insoluble glucose isomerase enzyme preparations are used in the production of... additional requirements for enzyme preparations in the Food Chemicals Codex, 3d Ed. (1981), p. 107, which...

  4. 21 CFR 184.1372 - Insoluble glucose isomerase enzyme preparations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Insoluble glucose isomerase enzyme preparations... enzyme preparations. (a) Insoluble glucose isomerase enzyme preparations are used in the production of... additional requirements for enzyme preparations in the Food Chemicals Codex, 3d Ed. (1981), p. 107, which...

  5. 21 CFR 184.1372 - Insoluble glucose isomerase enzyme preparations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Insoluble glucose isomerase enzyme preparations... enzyme preparations. (a) Insoluble glucose isomerase enzyme preparations are used in the production of... additional requirements for enzyme preparations in the Food Chemicals Codex, 3d Ed. (1981), p. 107, which...

  6. Vanadates form insoluble complexes with histones.

    PubMed

    Michele, D E; Thomsen, D; Louters, L L

    1997-07-01

    Vanadium oxoanions are known to have a variety of physiological effects including insulin-like activity, inhibition of phosphotyrosine phosphatases, as well as direct interactions with a variety of cellular proteins, such as microtubules. In this study, vanadate was found to form insoluble complexes with histones, as well as other positively charged proteins, in a concentration dependent fashion. This interaction occurred over a 0.5-10 mM range which corresponds to the concentration range required for many of vanadate's known physiological effects. Results from precipitation experiments using vanadate solutions with or without the yellow-orange decavanadate indicated that the decamer form is primarily responsible for this precipitation. Vanadate was able to selectively precipitate histones from soluble chromatin as well as from a soluble bacterial protein extract to which a low concentration of histones had been added. Vanadate was also able to effectively precipitate histone from solutions as low as 0.006 mg/mL histone. Thus, the selective precipitation of histones and other positively charged proteins by vanadate can be utilized as a tool for protein purification. In addition, this interaction may provide insight into the mechanisms for the physiological effects of vanadate.

  7. Adsorption of Ions at Uncharged Insoluble Monolayers.

    PubMed

    Peshkova, Tatyana V; Minkov, Ivan L; Tsekov, Roumen; Slavchov, Radomir I

    2016-09-06

    A method is proposed for the experimental determination of the adsorption of inorganic electrolytes at a surface covered with insoluble surfactant monolayer. This task is complicated by the fact that the change of the salt concentration alters both chemical potentials of the electrolyte and the surfactant. Our method resolves the question by combining data for the surface pressure versus area of the monolayer at several salt concentrations with data for the equilibrium spreading pressure of crystals of the surfactant (used to fix a standard state). We applied the method to alcohols spread at the surface of concentrated halide solutions. The measured salt adsorption is positive and has nonmonotonic dependence on the area per surfactant molecule. For the liquid expanded film, depending on the concentration, there is one couple of ions adsorbed per each 3-30 surfactant molecules. We analyzed which ion, the positive or the negative, stands closer to the surface, by measuring the effect of NaCl on the Volta potential of the monolayer. The potentiometric data suggest that Na(+) is specifically adsorbed, while Cl(-) remains in the diffuse layer, i.e., the surface is positively charged. The observed reverse Hofmeister series of the adsorptions of NaF, NaCl, and NaBr suggests the same conclusion holds for all these salts. The force that causes the adsorption of Na(+) seems to be the interaction of the ion with the dipole moment of the monolayer.

  8. Adsorption of Ions at Uncharged Insoluble Monolayers

    NASA Astrophysics Data System (ADS)

    Peshkova, T. V.; Minkov, I. L.; Tsekov, R.; Slavchov, R. I.

    2016-08-01

    A method is proposed for the experimental determination of the adsorption of inorganic electrolytes at a surface covered with insoluble surfactant monolayer. This task is complicated by the fact that the change of the salt concentration alters both chemical potentials of the electrolyte and the surfactant. Our method resolves the question by combining data for the surface pressure versus area of the monolayer at several salt concentrations with data for the equilibrium spreading pressure of crystals of the surfactant (used to fix a standard state). We applied the method to alcohols spread at the surface of concentrated halide solutions. The measured salt adsorption is positive and has nonmonotonic dependence on the area per surfactant molecule. For the liquid expanded film, depending on the concentration, there is one couple of ions adsorbed per each 3–30 surfactant molecules. We analyzed which ion, the positive or the negative, stands closer to the surface, by measuring the effect of NaCl on the Volta potential of the monolayer. The potentiometric data suggest that Na+ is specifically adsorbed, while Cl– remains in the diffuse layer, i.e., the surface is positively charged. The observed reverse Hofmeister series of the adsorptions of NaF, NaCl, and NaBr suggests the same conclusion holds for all these salts. The force that causes the adsorption of Na+ seems to be the interaction of the ion with the dipole moment of the monolayer.

  9. Water-Insoluble Photosensitizer Nanocolloids Stabilized by Supramolecular Interfacial Assembly towards Photodynamic Therapy

    PubMed Central

    Liu, Yamei; Ma, Kai; Jiao, Tifeng; Xing, Ruirui; Shen, Guizhi; Yan, Xuehai

    2017-01-01

    Nanoengineering of hydrophobic photosensitizers (PSs) is a promising approach for improved tumor delivery and enhanced photodynamic therapy (PDT) efficiency. A variety of delivery carriers have been developed for tumor delivery of PSs through the enhanced permeation and retention (EPR) effect. However, a high-performance PS delivery system with minimum use of carrier materials with excellent biocompatibility is highly appreciated. In this work, we utilized the spatiotemporal interfacial adhesion and assembly of supramolecular coordination to achieve the nanoengineering of water-insoluble photosensitizer Chlorin e6 (Ce6). The hydrophobic Ce6 nanoparticles are well stabilized in a aqueous medium by the interfacially-assembled film due to the coordination polymerization of tannic acid (TA) and ferric iron (Fe(III)). The resulting Ce6@TA-Fe(III) complex nanoparticles (referenced as Ce6@TA-Fe(III) NPs) significantly improves the drug loading content (~65%) and have an average size of 60 nm. The Ce6@TA-Fe(III) NPs are almost non-emissive as the aggregated states, but they can light up after intracellular internalization, which thus realizes low dark toxicity and excellent phototoxicity under laser irradiation. The Ce6@TA-Fe(III) NPs prolong blood circulation, promote tumor-selective accumulation of PSs, and enhanced antitumor efficacy in comparison to the free-carrier Ce6 in vivo evaluation. PMID:28230203

  10. Water-Insoluble Photosensitizer Nanocolloids Stabilized by Supramolecular Interfacial Assembly towards Photodynamic Therapy

    NASA Astrophysics Data System (ADS)

    Liu, Yamei; Ma, Kai; Jiao, Tifeng; Xing, Ruirui; Shen, Guizhi; Yan, Xuehai

    2017-02-01

    Nanoengineering of hydrophobic photosensitizers (PSs) is a promising approach for improved tumor delivery and enhanced photodynamic therapy (PDT) efficiency. A variety of delivery carriers have been developed for tumor delivery of PSs through the enhanced permeation and retention (EPR) effect. However, a high-performance PS delivery system with minimum use of carrier materials with excellent biocompatibility is highly appreciated. In this work, we utilized the spatiotemporal interfacial adhesion and assembly of supramolecular coordination to achieve the nanoengineering of water-insoluble photosensitizer Chlorin e6 (Ce6). The hydrophobic Ce6 nanoparticles are well stabilized in a aqueous medium by the interfacially-assembled film due to the coordination polymerization of tannic acid (TA) and ferric iron (Fe(III)). The resulting Ce6@TA-Fe(III) complex nanoparticles (referenced as Ce6@TA-Fe(III) NPs) significantly improves the drug loading content (~65%) and have an average size of 60 nm. The Ce6@TA-Fe(III) NPs are almost non-emissive as the aggregated states, but they can light up after intracellular internalization, which thus realizes low dark toxicity and excellent phototoxicity under laser irradiation. The Ce6@TA-Fe(III) NPs prolong blood circulation, promote tumor-selective accumulation of PSs, and enhanced antitumor efficacy in comparison to the free-carrier Ce6 in vivo evaluation.

  11. Boric acid inhibition of steam generator materials corrosion

    SciTech Connect

    Wootten, M.J.; Wolfe, C.R.; Hermer, R.E.

    1985-01-01

    In 1974, Westinghouse recommended a change from phosphate water chemistry control for nuclear steam generators to one in which no solids are intentionally added, called all volatile treatment (AVT). The reason for the recommended change in water chemistry control was the occurrence of phosphate thinning of the Alloy 600 heat transfer tubes in some operating plants. Since the change over to AVT, other types of corrosion from impurities in the water have been observed of the materials of construction of nuclear steam generators. Initially, several plants observed denting, which is caused by the corrosion of the carbon steel tube support plates. After 8 yr of usage as a denting inhibitor in nuclear plants, no detrimental effects have been identified as due to boric acid. It is believed that boric acid will inhibit denting-type corrosion and caustic attack of Alloy 600; however, it must be stressed that it is not a substitute for good chemistry practices and all levels and disciplines within the operating plant should recognize the importance of rigorous, long-term chemistry control.

  12. Solubilization of insoluble inorganic phosphate by Burkholderia cepacia DA23 isolated from cultivated soil

    PubMed Central

    Song, Ok-Ryul; Lee, Seung-Jin; Lee, Yong-Seok; Lee, Sang-Cheol; Kim, Keun-Ki; Choi, Yong-Lark

    2008-01-01

    A mineral phosphate solubilizing bacterium, Burkholderia cepacia DA23 has been isolated from cultivated soils. Phosphate-solubilizing activities of the strain against three types of insoluble phosphate were quantitatively determined. When 3% of glucose concentration was used for carbon source, the strain had a marked mineral phosphate-solubilizing activity. Mineral phosphate solubilization was directly related to the pH drop by the strain. Analysis of the culture medium by high pressure liquid chromatography identified gluconic acid as the main organic acid released by Burkholderia cepacia DA23. Gluconic acid production was apparently the result of the glucose dehydrogenase activity and glucose dehydrogenase was affected by phosphate regulation. PMID:24031195

  13. Microencapsulation of pancreatic islets in a water insoluble polyacrylate.

    PubMed

    Sugamori, M E; Sefton, M V

    1989-01-01

    Rat pancreatic islets were encapsulated in a water insoluble polyacrylate (Eudragit RL), a model polymer, by coaxial extrusion and interfacial precipitation. Despite exposure to organic solvents and nonsolvents (diethyl phthalate, corn oil, and mineral oil) and to shear, the islets survived encapsulation. They continued to secrete insulin into the tissue culture medium and responded to glucose in both static glucose challenges and perifusion assays as well and as long as control islets which were not encapsulated, but were maintained in tissue culture alongside the encapsulated islets. Unfortunately, there was a great deal of variability in the performance of all islets studied, making unequivocal conclusions difficult. Some encapsulated islets survived more than 140 days in vitro and histologically appeared healthy. However, there appeared to be a general deterioration in insulin secretion capacity following prolonged culture in all islets, with corresponding changes (e.g., central necrosis) visible by microscopy. Although Eudragit RL is not practical as an encapsulation polymer, this study was useful in demonstrating that islets may be encapsulated in materials other than alginate-polylysine, and ultimately in materials that may have a more optimum blend of the desired properties: biocompatibility, permselectivity, and mechanical durability.

  14. Insoluble coatings for Stirling engine heat pipe condenser surfaces

    NASA Technical Reports Server (NTRS)

    Dussinger, Peter M.

    1993-01-01

    The work done by Thermacore, Inc., Lancaster, Pennsylvania, for the Phase 1, 1992 SBIR National Aeronautics and Space Administration Contract, 'Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces' is described. The work was performed between January 1992 and July 1992. Stirling heat engines are being developed for electrical power generation use on manned and unmanned earth orbital and planetary missions. Dish Stirling solar systems and nuclear reactor Stirling systems are two of the most promising applications of the Stirling engine electrical power generation technology. The sources of thermal energy used to drive the Stirling engine typically are non-uniform in temperature and heat flux. Liquid metal heat pipe receivers are used as thermal transformers and isothermalizers to deliver the thermal energy at a uniform high temperature to the heat input section of the Stirling engine. The use of a heat pipe receiver greatly enhances system efficiency and potential life span. One issue that is raised during the design phase of heat pipe receivers is the potential solubility corrosion of the Stirling engine heat input section by the liquid metal working fluid. This Phase 1 effort initiated a program to evaluate and demonstrate coatings, applied to nickel based Stirling engine heater head materials, that are practically 'insoluble' in sodium, potassium, and NaK. This program initiated a study of nickel aluminide as a coating and developed and demonstrated a heat pipe test vehicle that can be used to test candidate materials and coatings. Nickel 200 and nickel aluminide coated Nickel 200 were tested for 1000 hours at 800 C at a condensation heat flux of 25 W/sq cm. Subsequent analyses of the samples showed no visible sign of solubility corrosion of either coated or uncoated samples. The analysis technique, photomicrographs at 200X, has a resolution of better than 2.5 microns (.0001 in). The results indicate that the heat pipe environment is not directly

  15. Insoluble coatings for Stirling engine heat pipe condenser surfaces

    NASA Astrophysics Data System (ADS)

    Dussinger, Peter M.

    1993-09-01

    The work done by Thermacore, Inc., Lancaster, Pennsylvania, for the Phase 1, 1992 SBIR National Aeronautics and Space Administration Contract, 'Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces' is described. The work was performed between January 1992 and July 1992. Stirling heat engines are being developed for electrical power generation use on manned and unmanned earth orbital and planetary missions. Dish Stirling solar systems and nuclear reactor Stirling systems are two of the most promising applications of the Stirling engine electrical power generation technology. The sources of thermal energy used to drive the Stirling engine typically are non-uniform in temperature and heat flux. Liquid metal heat pipe receivers are used as thermal transformers and isothermalizers to deliver the thermal energy at a uniform high temperature to the heat input section of the Stirling engine. The use of a heat pipe receiver greatly enhances system efficiency and potential life span. One issue that is raised during the design phase of heat pipe receivers is the potential solubility corrosion of the Stirling engine heat input section by the liquid metal working fluid. This Phase 1 effort initiated a program to evaluate and demonstrate coatings, applied to nickel based Stirling engine heater head materials, that are practically 'insoluble' in sodium, potassium, and NaK. This program initiated a study of nickel aluminide as a coating and developed and demonstrated a heat pipe test vehicle that can be used to test candidate materials and coatings. Nickel 200 and nickel aluminide coated Nickel 200 were tested for 1000 hours at 800 C at a condensation heat flux of 25 W/sq cm. Subsequent analyses of the samples showed no visible sign of solubility corrosion of either coated or uncoated samples. The analysis technique, photomicrographs at 200X, has a resolution of better than 2.5 microns (.0001 in). The results indicate that the heat pipe environment is not directly

  16. [Reaction of bone tissue elements on synthetic bioresorbable materials based on lactic and glycolic acids].

    PubMed

    Kulakov, A A; Grigor'ian, A S

    2014-01-01

    The aim of the study was to evaluate the adverse effects of synthetic polymeric bioresorbable materials based on lactic and glycolic acids on the bone tissue. The study was carried-out on 40 Wister-line rats. Four types of bioresorbable polymeric materials were implanted: PolyLactide Glycolide Acid (PLGA), Poly-L-Lactide Acid (PLLA); Poly-96L/4D-Lactide Acid (96/4 PLDLA); Poly-70L/30D-Lactide Acid (70/30 PLDLA). The results showed connective tissue formation (fibrointegration) bordering bone adjacent to implanted materials. This proved the materials to cause pathogenic influence on the bone which mechanisms are described in the article.

  17. Cytotoxicity of corrosion products of degradable Fe-based stents: relevance of pH and insoluble products.

    PubMed

    Fagali, Natalia S; Grillo, Claudia A; Puntarulo, Susana; Fernández Lorenzo de Mele, Mónica A

    2015-04-01

    Fe-based biodegradable metallic materials (Fe-BMMs) have been proposed for cardiovascular applications and are expected to disappear via corrosion after an appropriate period. However, in vivo studies showed that Fe ions release leads to accumulation of orange and brownish insoluble products at the biomaterial/cell interface. As an additional consequence, sharp changes in pH may affect the biocompatibility of these materials. In the present work, the experimental protocols were designed with the aim of evaluating the relative importance that these factors have on biocompatibility evaluation of BMMs. Mitochondrial activity (MTT assay) and thiobarbituric acid reactive substances (TBARS) assay on mammalian cells, exposed to 1-5 mM of added Fe3+ salt, were assessed and compared with results linked exclusively to pH effects. Soluble Fe concentration in culture medium and intracellular Fe content were also determined. The results showed that: (i) mitochondrial activity was affected by pH changes over the entire range of concentrations of added Fe3+ assayed, (ii) at the highest added Fe3+ concentrations (≥3 mM), precipitation was detected and the cells were able to incorporate the precipitate, that seems to be linked to cell damage, (iii) the extent of precipitation depends on the Fe/protein concentration ratio; and (iv) lipid peroxidation products were detected over the entire range of concentrations of added Fe3+. Hence, a new approach opens in the biocompatibility evaluation of Fe-based BMMs, since the cytotoxicity would not be solely a function of released (and soluble) ions but of the insoluble degradation product amount and the pH falling at the biomaterial/cell interface. The concentration of Fe-containing products at the interface depends on diffusional conditions in a very complex way that should be carefully analyzed in the future.

  18. General introduction: recombinant protein production and purification of insoluble proteins.

    PubMed

    Ferrer-Miralles, Neus; Saccardo, Paolo; Corchero, José Luis; Xu, Zhikun; García-Fruitós, Elena

    2015-01-01

    Proteins are synthesized in heterologous systems because of the impossibility to obtain satisfactory yields from natural sources. The production of soluble and functional recombinant proteins is among the main goals in the biotechnological field. In this context, it is important to point out that under stress conditions, protein folding machinery is saturated and this promotes protein misfolding and, consequently, protein aggregation. Thus, the selection of the optimal expression organism and the most appropriate growth conditions to minimize the formation of insoluble proteins should be done according to the protein characteristics and downstream requirements. Escherichia coli is the most popular recombinant protein expression system despite the great development achieved so far by eukaryotic expression systems. Besides, other prokaryotic expression systems, such as lactic acid bacteria and psychrophilic bacteria, are gaining interest in this field. However, it is worth mentioning that prokaryotic expression system poses, in many cases, severe restrictions for a successful heterologous protein production. Thus, eukaryotic systems such as mammalian cells, insect cells, yeast, filamentous fungus, and microalgae are an interesting alternative for the production of these difficult-to-express proteins.

  19. Organic Analysis in Miller Range 090657 and Buckley Island 10933 CR2 Chondrites: Part 1 In-Situ Observation of Carbonaceous Material

    NASA Technical Reports Server (NTRS)

    Cao, T.; Nakamura-Messenger, K.; Berger, E. L.; Burton, A. S.; Messenger, S.; Clemett, S. J.

    2016-01-01

    Primitive carbonaceous chondrites contain a wide variety of organic material, ranging from soluble discrete molecules to insoluble unstructured kerogen-like component as well as structured nano-globules of macromolecular carbon. The relationship between the soluble organic molecules, macromolecular organic material, and host minerals are poorly understood. Due to the differences in extractability of soluble and insoluble organic materials, the analysis methods for each differ and are often performed independently. The combination of soluble and insoluble analyses, when performed concurrently, can provide a wider understanding on spatial distribution, and elemental, structural and isotopic composition of organic material in primitive meteorites. Furthermore, they can provide broader perspective on how extraterrestrial organic ma-terials potentially contributed to the synthesis of life's essential compounds such as amino acids, sugar acids, activated phosphates and nucleobases.

  20. Dissolving mechanism of strain P17 on insoluble phosphorus of yellow-brown soil

    PubMed Central

    Chuan-qing, Zhong; Guang-xiang, Cao; Wei-yi, Huang; Xing-she, Luan; Yi-fei, Yang

    2014-01-01

    Strain P17 was a bacterial strain identified as Bacillus megaterium isolated from ground accumulating phosphate rock powder. The fermentation broth of strain P17 and the yellow-brown soil from Nanjing Agricultural University garden were collected to conduct this study. The simulation of fixed insoluble phosphorous forms after applying calcium superphosphate into yellow-brown soil was performed in pots, while available P and total P of soil were extremely positive correlative with those of groundwater. Then the dissolving effect of strain P17 on insoluble P of yellow-brown soil was studied. Results showed that Bacillus megaterium strain P17 had notable solubilizing effect on insoluble phosphates formed when too much water-soluble phosphorous fertilizer used. During 100 days after inoculation, strain P17 was dominant. Until the 120th day, compared with water addition, available P of strain P17 inoculation treated soil increased by 3 times with calcium superphosphate addition. Besides available P, pH, activity of acid and alkaline phosphatase and population of P-solubilizing microbes were detected respectively. P-solubilizing mechanism of P-solubilizing bacteria strain P17 seems to be a synergetic effect of pH decrease, organic acids, phosphatase, etc. PMID:25477929

  1. Dissolving mechanism of strain P17 on insoluble phosphorus of yellow-brown soil.

    PubMed

    Zhong, Chuan-qing; Cao, Guang-xiang; Huang, Wei-yi; Luan, Xing-she; Yang, Yi-fei

    2014-01-01

    Strain P17 was a bacterial strain identified as Bacillus megaterium isolated from ground accumulating phosphate rock powder. The fermentation broth of strain P17 and the yellow-brown soil from Nanjing Agricultural University garden were collected to conduct this study. The simulation of fixed insoluble phosphorous forms after applying calcium superphosphate into yellow-brown soil was performed in pots, while available P and total P of soil were extremely positive correlative with those of groundwater. Then the dissolving effect of strain P17 on insoluble P of yellow-brown soil was studied. Results showed that Bacillus megaterium strain P17 had notable solubilizing effect on insoluble phosphates formed when too much water-soluble phosphorous fertilizer used. During 100 days after inoculation, strain P17 was dominant. Until the 120th day, compared with water addition, available P of strain P17 inoculation treated soil increased by 3 times with calcium superphosphate addition. Besides available P, pH, activity of acid and alkaline phosphatase and population of P-solubilizing microbes were detected respectively. P-solubilizing mechanism of P-solubilizing bacteria strain P17 seems to be a synergetic effect of pH decrease, organic acids, phosphatase, etc.

  2. Wollastonite hybridizing stearic acid as thermal energy storage material

    NASA Astrophysics Data System (ADS)

    Xu, Dawei; Yang, Huaming

    2014-11-01

    This paper reported on the preparation of a novel stearic acid (SA)/wollastonite (W) composite as a form-stable phase change material (PCM) for thermal energy-storage (TES) by vacuum impregnation, and especially investigated the effect of the size grade of W on the thermal properties of the SA/W composite. Samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), laser particle-size analysis, and differential scanning calorimetry (DSC). Natural W (Wr) was classified into four size grades by wet screening. The results indicate that no chemical reaction took place between SA and W, and the SA load in the SA/W composite increased with an increase in the length/diameter (L/D) ratio of the W. The SA/W composite with a W L/D ratio of 22.5 exhibited latent heats of melting and freezing of 58.64 J/g and 56.95 J/g, respectively, which was higher than those of the composite incorporating natural W. We believe that the as-prepared form-stable PCM composite could provide a potential means of TES for the concentrated solar power.

  3. Materials study supporting thermochemical hydrogen cycle sulfuric acid decomposer design

    NASA Astrophysics Data System (ADS)

    Peck, Michael S.

    Increasing global climate change has been driven by greenhouse gases emissions originating from the combustion of fossil fuels. Clean burning hydrogen has the potential to replace much of the fossil fuels used today reducing the amount of greenhouse gases released into the atmosphere. The sulfur iodine and hybrid sulfur thermochemical cycles coupled with high temperature heat from advanced nuclear reactors have shown promise for economical large-scale hydrogen fuel stock production. Both of these cycles employ a step to decompose sulfuric acid to sulfur dioxide. This decomposition step occurs at high temperatures in the range of 825°C to 926°C dependent on the catalysis used. Successful commercial implementation of these technologies is dependent upon the development of suitable materials for use in the highly corrosive environments created by the decomposition products. Boron treated diamond film was a potential candidate for use in decomposer process equipment based on earlier studies concluding good oxidation resistance at elevated temperatures. However, little information was available relating the interactions of diamond and diamond films with sulfuric acid at temperatures greater than 350°C. A laboratory scale sulfuric acid decomposer simulator was constructed at the Nuclear Science and Engineering Institute at the University of Missouri-Columbia. The simulator was capable of producing the temperatures and corrosive environments that process equipment would be exposed to for industrialization of the sulfur iodide or hybrid sulfur thermochemical cycles. A series of boron treated synthetic diamonds were tested in the simulator to determine corrosion resistances and suitability for use in thermochemical process equipment. These studies were performed at twenty four hour durations at temperatures between 600°C to 926°C. Other materials, including natural diamond, synthetic diamond treated with titanium, silicon carbide, quartz, aluminum nitride, and Inconel

  4. Automated sequencing of insoluble peptides using detergent. Bacteriophage fl coat protein.

    PubMed

    Bailey, G S; Gillett, D; Hill, D F; Petersen, G B

    1977-04-10

    Peptides which are highly nonpolar and insoluble under moderate conditions of pH and ionic strength cannot be subjected to automated sequence analysis. We report a method for solubilization of one such peptide, bacteriophage fl coat protein, by chemical modification in the presence of sodium dodecyl sulfate. Following this treatment the 50-residue peptide was degraded stepwise in an automated sequenator using a single cleavage Quadrol program with high repetitive yield through residue 47. We also report a modified program using detergent incorporated into dimethylallylamine buffer which permitted sequencing with high repetitive yields for at least the first 18 residues of the unmodified and otherwise highly insoluble coat protein. The presence of detergent caused no observable difficulties in detection of residues by gas chromatography, thin layer chromatography, or amino acid analysis.

  5. Structural and physico-chemical properties of insoluble rice bran fiber: effect of acid–base induced modifications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The structural modifications of insoluble rice bran fiber (IRBF) by sequential regimes of sulphuric acid (H2SO4) and their effects on the physicochemical attributes were studied. The increment of H2SO4 concentration resulted in decreased water holding capacity that ultimately enhanced the oil bindin...

  6. An alkaline one-pot reaction to synthesize luminescent Eu-BTC MOF nanorods, highly pure and water-insoluble, under room conditions

    NASA Astrophysics Data System (ADS)

    Medina-Velazquez, D. Y.; Alejandre-Zuniga, B. Y.; Loera-Serna, S.; Ortiz, E. M.; Morales-Ramirez, A. de J.; Garfias-Garcia, E.; Garcia-Murillo, A.; Falcony, C.

    2016-12-01

    The increasing demand for optoelectronic devices requires the development of luminescent materials with high luminescence efficiency and low energy demands, and the metalorganic frameworks (MOFs) with lanthanides ions offer great potential in this area. The metalorganic materials provide properties of flexibility, low density, low-cost methods of synthesis, and insolubility in water, which gives them an advantage over traditional phosphors. In this study, a benzenetricarboxylate ligand (BTC) with a Eu3+ MOF was synthesized, and its structural and luminescent properties were measured. The metalorganic compound was generated in a one-pot reaction from europium nitrate and trimesic acid precursors. Through characterization by X-ray diffraction powder, infrared spectroscopy, SEM structural characterization, and luminescent spectroscopy, the formation of Europium benzenetricarboxylate (Eu-BTC) MOF nanorods was tested and the calculated value was in the range of 30-60 nm. A red luminescent emission with high intensity was observed for all the procedures.

  7. Acid Precipitation Awareness Curriculum Materials in the Life Sciences.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.

    1983-01-01

    Provides an outline of course content for acid precipitation and two acid rain activities (introduction to pH and effects of acid rain on an organism). Information for obtaining 20 additional activities as well as an information packet containing booklets, pamphlets, and articles are also provided. (JN)

  8. Hydrofluoric Acid Corrosion Study of High-Alloy Materials

    SciTech Connect

    Osborne, P.E.

    2002-09-11

    A corrosion study involving high-alloy materials and concentrated hydrofluoric acid (HF) was conducted in support of the Molten Salt Reactor Experiment Conversion Project (CP). The purpose of the test was to obtain a greater understanding of the corrosion rates of materials of construction currently used in the CP vs those of proposed replacement parts. Results of the study will help formulate a change-out schedule for CP parts. The CP will convert slightly less than 40 kg of {sup 233}U from a gas (UF{sub 6}) sorbed on sodium fluoride pellets to a more stable oxide (U{sub 3}O{sub 8}). One by-product of the conversion is the formation of concentrated HF. Six moles of highly corrosive HF are produced for each mole of UF{sub 6} converted. This acid is particularly corrosive to most metals, elastomers, and silica-containing materials. A common impurity found in {sup 233}U is {sup 232}U. This impurity isotope has several daughters that make the handling of the {sup 233}U difficult. Traps of {sup 233}U may have radiation fields of up to 400 R at contact, a situation that makes the process of changing valves or working on the CP more challenging. It is also for this reason that a comprehensive part change-out schedule must be established. Laboratory experiments involving the repeated transfer of HF through 1/2-in. metal tubing and valves have proven difficult due to the corrosivity of the HF upon contact with all wetted parts. Each batch of HF is approximately 1.5 L of 33 wt% HF and is transferred most often as a vapor under vacuum and at temperatures of up to 250 C. Materials used in the HF side of the CP include Hastelloy C-276 and Monel 400 tubing, Haynes 230 and alloy C-276 vessels, and alloy 400 valve bodies with Inconel (alloy 600) bellows. The chemical compositions of the metals discussed in this report are displayed in Table 1. Of particular concern are the almost 30 vendor-supplied UG valves that have the potential for exposure to HF. These valves have been

  9. Low-Vacuum Deposition of Glutamic Acid and Pyroglutamic Acid: A Facile Methodology for Depositing Organic Materials beyond Amino Acids.

    PubMed

    Sugimoto, Iwao; Maeda, Shunsaku; Suda, Yoriko; Makihara, Kenji; Takahashi, Kazuhiko

    2014-01-01

    Thin layers of pyroglutamic acid (Pygl) have been deposited by thermal evaporation of the molten L-glutamic acid (L-Glu) through intramolecular lactamization. This deposition was carried out with the versatile handmade low-vacuum coater, which was simply composed of a soldering iron placed in a vacuum degassing resin chamber evacuated by an oil-free diaphragm pump. Molecular structural analyses have revealed that thin solid film evaporated from the molten L-Glu is mainly composed of L-Pygl due to intramolecular lactamization. The major component of the L-Pygl was in β-phase and the minor component was in γ-phase, which would have been generated from partial racemization to DL-Pygl. Electron microscopy revealed that the L-Glu-evaporated film generally consisted of the 20 nm particulates of Pygl, which contained a periodic pattern spacing of 0.2 nm intervals indicating the formation of the single-molecular interval of the crystallized molecular networks. The DL-Pygl-evaporated film was composed of the original DL-Pygl preserving its crystal structures. This methodology is promising for depositing a wide range of the evaporable organic materials beyond amino acids. The quartz crystal resonator coated with the L-Glu-evaporated film exhibited the pressure-sensing capability based on the adsorption-desorption of the surrounding gas at the film surface.

  10. Low-Vacuum Deposition of Glutamic Acid and Pyroglutamic Acid: A Facile Methodology for Depositing Organic Materials beyond Amino Acids

    PubMed Central

    Sugimoto, Iwao; Maeda, Shunsaku; Suda, Yoriko; Makihara, Kenji; Takahashi, Kazuhiko

    2014-01-01

    Thin layers of pyroglutamic acid (Pygl) have been deposited by thermal evaporation of the molten L-glutamic acid (L-Glu) through intramolecular lactamization. This deposition was carried out with the versatile handmade low-vacuum coater, which was simply composed of a soldering iron placed in a vacuum degassing resin chamber evacuated by an oil-free diaphragm pump. Molecular structural analyses have revealed that thin solid film evaporated from the molten L-Glu is mainly composed of L-Pygl due to intramolecular lactamization. The major component of the L-Pygl was in β-phase and the minor component was in γ-phase, which would have been generated from partial racemization to DL-Pygl. Electron microscopy revealed that the L-Glu-evaporated film generally consisted of the 20 nm particulates of Pygl, which contained a periodic pattern spacing of 0.2 nm intervals indicating the formation of the single-molecular interval of the crystallized molecular networks. The DL-Pygl-evaporated film was composed of the original DL-Pygl preserving its crystal structures. This methodology is promising for depositing a wide range of the evaporable organic materials beyond amino acids. The quartz crystal resonator coated with the L-Glu-evaporated film exhibited the pressure-sensing capability based on the adsorption-desorption of the surrounding gas at the film surface. PMID:25254114

  11. Development of polylactic acid-based materials through reactive modification

    NASA Astrophysics Data System (ADS)

    Fowlks, Alison Camille

    2009-12-01

    Polylactic acid (PLA)-based systems have shown to be of great potential for the development of materials requiring biobased content, biodegradation, and sufficient properties. The efforts in this study are directed toward addressing the current research need to overcome some of the inherent drawbacks of PLA. To meet this need, reactive extrusion was employed to develop new materials based on PLA by grafting, compounding, and polymer blending. In the first part of this work, maleic anhydride (MA) was grafted onto PLA by reactive extrusion. Two structurally different peroxides were used to initiate grafting and results were reported on the basis of grafting, molecular weight, and thermal behavior. An inverse relationship between degree of grafting and molecular weight was established. It was also found that, regardless of peroxide type, there is an optimum peroxid-to-MA ratio of 0.5:2 that promotes maximum grafting, beyond which degradation reactions become predominant. Overall, it was found that the maleated copolymer (MAPLA) could be used as an interfacial modifier in PLA-based composites. Therefore, MAPLA was incorporated into PLA-talc composites in varying concentrations. The influence of the MAPLA addition on the mechanical and thermal behavior was investigated. When added in an optimum concentration, MAPLA improved the tensile strength and crystallization of the composite. Furthermore, microscopic observation confirmed the compatibilization effect of MAPLA in PLA-talc composites. Vinyltrimethoxysilane was free-radically grafted onto the backbone of PLA and subsequently moisture crosslinked. The effects of monomer, initiator, and catalyst concentration on the degree of crosslinking and the mechanical and thermal properties were investigated. The presence of a small amount of catalyst showed to be a major contributor to the crosslinking formation in the time frame investigated, shown by an increase in gel content and decrease in crystallinity. Furthermore

  12. 13C NMR spectroscopy of the insoluble carbon of carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Cronin, J. R.; Pizzarello, S.; Frye, J. S.

    1987-01-01

    13C NMR spectra have been obtained of the insoluble carbon residues resulting from HF-digestion of three carbonaceous chondrites, Orgueil (C1), Murchison (CM2), and Allende (CV3). Spectra obtained using the cross polarization magic-angle spinning technique show two major features attributable respectively to carbon in aliphatic/olefinic structures. The spectrum obtained from the Allende sample was weak, presumably as a consequence of its low hydrogen content. Single pulse excitation spectra, which do not depend on 1H-13C polarization transfer for signal enhancement were also obtained. These spectra, which may be more representative of the total carbon in the meteorite samples, indicate a greater content of carbon in aromatic/olefinic structures. These results suggest that extensive polycyclic aromatic sheets are important structural features of the insoluble carbon of all three meteorites. The Orgueil and Murchison materials contain additional hydrogenated aromatic/olefinic and aliphatic groups.

  13. [Determination of glutamic acid in biological material by capillary electrophoresis].

    PubMed

    Narezhnaya, E; Krukier, I; Avrutskaya, V; Degtyareva, A; Igumnova, E A

    2015-01-01

    The conditions for the identification and determination of Glutamic acid by capillary zone electrophoresis without their preliminary derivatization have been optimized. The effect of concentration of buffer electrolyte and pH on determination of Glutamic acid has been investigated. It is shown that the 5 Mm borate buffer concentration and a pH 9.15 are optimal. Quantitative determination of glutamic acid has been carried out using a linear dependence between the concentration of the analyte and the area of the peak. The accuracy and reproducibility of the determination are confirmed by the method "introduced - found". Glutamic acid has been determined in the placenta homogenate. The duration of analysis doesn't exceed 30 minutes. The results showed a decrease in the level of glutamic acid in cases of pregnancy complicated by placental insufficiency compared with the physiological, and this fact allows to consider the level of glutamic acid as a possible marker of complicated pregnancy.

  14. Improvement of thermostability and activity of Trichoderma reesei endo-xylanase Xyn III on insoluble substrates.

    PubMed

    Matsuzawa, Tomohiko; Kaneko, Satoshi; Yaoi, Katsuro

    2016-09-01

    Trichoderma reesei Xyn III, an endo-β-1,4-xylanase belonging to glycoside hydrolase family 10 (GH10), is vital for the saccharification of xylans in plant biomass. However, its enzymatic thermostability and hydrolytic activity on insoluble substrates are low. To overcome these difficulties, the thermostability of Xyn III was improved using random mutagenesis and directed evolution, and its hydrolytic activity on insoluble substrates was improved by creating a chimeric protein. In the screening of thermostable Xyn III mutants from a random mutagenesis library, we identified two amino acid residues, Gln286 and Asn340, which are important for the thermostability of Xyn III. The Xyn III Gln286Ala/Asn340Tyr mutant showed xylanase activity even after heat treatment at 60 °C for 30 min or 50 °C for 96 h, indicating a dramatic enhancement in thermostability. In addition, we found that the addition of a xylan-binding domain (XBD) to the C-terminal of Xyn III improved its hydrolytic activity on insoluble xylan.

  15. CR@BaSO4: an acid rain-indicating material.

    PubMed

    Gao, Hong-Wen; Xu, Xin-Hui

    2011-12-28

    The CR@BaSO(4) hybrid was synthesized, characterized and used as an acid rain-indicating (ARI) material. A painted ARI umbrella was discolored after exposure to simulated acid rain of pH 5 or less and returned to the initial color after the rain stopped. Such a functionalized material may make acid rain visual to remind people in real-time.

  16. Graphitization of Organic Material in a Progressively Metamorphosed Precambrian Iron Formation.

    PubMed

    French, B M

    1964-11-13

    Organic matter in the sedimentary Biwabik iron formation in northern Minnesota shows a progressive increase in crystallinity where the formation is metamorphosed by the intrusive Duluth gabbro complex. X-ray diffraction of acid-insoluble residues shows that there is a complete range in crystallinity, from amorphous material in the unmetamorphosed sediments to completely crystalline graphite adjacent to the gabbro.

  17. Detection of the cytotoxicity of water-insoluble fraction of cigarette smoke by direct exposure to cultured cells at an air-liquid interface.

    PubMed

    Nara, Hidenori; Fukano, Yasuo; Nishino, Tomoki; Aufderheide, Michaela

    2013-07-01

    For the biological evaluation of cigarette smoke in vitro, the particulate phase (PP) and the gas vapor phase (GVP) of mainstream smoke have usually been collected individually and exposed to biological material such as cultured cells. Using this traditional method, the GVP is collected by bubbling in an aqueous solution such as phosphate-buffered saline (PBS). In such a way the water-insoluble GVP fraction is excluded from the GVP, meaning that the toxic potential of the water-insoluble GVP fraction has hardly been investigated so far. In our experiments we used a direct exposure method to expose cells at the air-liquid interface (ALI) to the water-insoluble GVP fraction for demonstrating its toxicological/biological activity. In order to isolate the water-insoluble GVP fraction from mainstream smoke, the GVP was passed through 6 impingers connected in series with PBS. After direct exposure of Chinese hamster ovary cells (CHO-K1) with the water-insoluble GVP fraction in the CULTEX(®) system its cytotoxicity was assayed by using the neutral red uptake assay. The water-insoluble GVP fraction was proven to be less cytotoxic than the water-soluble GVP fraction, but showed a significant effect in a dose-dependent manner. The results of this study showed that the direct exposure of cultivated cells at the air-liquid interface offers the possibility to analyze the biological and toxicological activities of all fractions of cigarette smoke including the water-insoluble GVP fraction.

  18. Materials and methods for efficient lactic acid production

    DOEpatents

    Zhou, Shengde; Ingram, Lonnie O'Neal; Shanmugam, Keelnatham T.; Yomano, Lorraine; Grabar, Tammy B.; Moore, Jonathan C.

    2009-12-08

    The present invention provides derivatives of ethanologenic Escherichia coli K011 constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  19. Materials and methods for efficient lactic acid production

    SciTech Connect

    Zhou, Shengde; Ingram, Lonnie O'Neal; Shanmugam, Keelnatham T; Yomano, Lorraine; Grabar, Tammy B; Moore, Jonathan C

    2013-04-23

    The present invention provides derivatives of Escherichia coli constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  20. An oral controlled release system for ambroxol hydrochloride containing a wax and a water insoluble polymer.

    PubMed

    Chi, Na; Guo, Ju Hong; Zhang, Yu; Zhang, Wei; Tang, Xing

    2010-01-01

    This study was carried out to develop and optimize oral sustained-release formulations for Ambroxol hydrochloride matrix pellets using a combination of wax and water-insoluble polymer, glyceryl behenate (Compritol 888 ATO) and Ethylcellulose (EC(7 FP)). It involved three factors: the content of Compritol 888 ATO (X(1)), EC(7 FP) (X(2)), and the matrix formation methods (X(3)), as independent variables. The drug release percentages at 1, 2 and 4 h were the target responses and were restricted to 15-45% (Y(1)), 45-80% (Y(2)) and 80-100% (Y(3)), respectively. The final blend formulation prepared by extrusion spheronization, was achieved with 27.00% (w/w) Ambroxol hydrochloride, 48.70% (w/w) Compritol 888 ATO, and 24.30% (w/w) EC(7 Fp) with 40 degrees C for 12 h. Comparing the single matrix materials consisting of just the wax or water-insoluble in the complex matrix system containing wax and water-insoluble polymer, the release of the drug can be far more retarded, when the formulations have undergone the process of heat treatment. Furthermore, the combination of the two polymers, with flexible matrix formation methods, will offer a very promising way of producing matrix pellets instead of coated controlled-release pellets to meet various demands of drug release.

  1. Material compatibility evaluation for DWPF nitric-glycolic acid-literature review

    SciTech Connect

    Mickalonis, J.; Skidmore, E.

    2013-06-01

    Glycolic acid is being evaluated as an alternative for formic and nitric acid in the DWPF flowsheet. Demonstration testing and modeling for this new flowsheet has shown that glycolic acid and glycolate has a potential to remain in certain streams generated during the production of the nuclear waste glass. A literature review was conducted to assess the impact of glycolic acid on the corrosion of the materials of construction for the DWPF facility as well as facilities downstream which may have residual glycolic acid and glycolates present. The literature data was limited to solutions containing principally glycolic acid.

  2. Layered materials with coexisting acidic and basic sites for catalytic one-pot reaction sequences.

    PubMed

    Motokura, Ken; Tada, Mizuki; Iwasawa, Yasuhiro

    2009-06-17

    Acidic montmorillonite-immobilized primary amines (H-mont-NH(2)) were found to be excellent acid-base bifunctional catalysts for one-pot reaction sequences, which are the first materials with coexisting acid and base sites active for acid-base tamdem reactions. For example, tandem deacetalization-Knoevenagel condensation proceeded successfully with the H-mont-NH(2), affording the corresponding condensation product in a quantitative yield. The acidity of the H-mont-NH(2) was strongly influenced by the preparation solvent, and the base-catalyzed reactions were enhanced by interlayer acid sites.

  3. Custom fabrication of biomass containment devices using 3-D printing enables bacterial growth analyses with complex insoluble substrates

    SciTech Connect

    Nelson, Cassandra E.; Beri, Nina R.; Gardner, Jeffrey G.

    2016-09-21

    Physiological studies of recalcitrant polysaccharide degradation are challenging for several reasons, one of which is the difficulty in obtaining a reproducibly accurate real-time measurement of bacterial growth using insoluble substrates. Current methods suffer from several problems including (i) high background noise due to the insoluble material interspersed with cells, (ii) high consumable and reagent cost and (iii) significant time delay between sampling and data acquisition. A customizable substrate and cell separation device would provide an option to study bacterial growth using optical density measurements. To test this hypothesis we used 3-D printing to create biomass containment devices that allow interaction between insoluble substrates and microbial cells but do not interfere with spectrophotometer measurements. Evaluation of materials available for 3-D printing indicated that UV-cured acrylic plastic was the best material, being superior to nylon or stainless steel when examined for heat tolerance, reactivity, and ability to be sterilized. Cost analysis of the 3-D printed devices indicated they are a competitive way to quantitate bacterial growth compared to viable cell counting or protein measurements, and experimental conditions were scalable over a 100-fold range. The presence of the devices did not alter growth phenotypes when using either soluble substrates or insoluble substrates. Furthermore, we applied biomass containment to characterize growth of Cellvibrio japonicus on authentic lignocellulose (non-pretreated corn stover), and found physiological evidence that xylan is a significant nutritional source despite an abundance of cellulose present.

  4. Custom fabrication of biomass containment devices using 3-D printing enables bacterial growth analyses with complex insoluble substrates

    DOE PAGES

    Nelson, Cassandra E.; Beri, Nina R.; Gardner, Jeffrey G.

    2016-09-21

    Physiological studies of recalcitrant polysaccharide degradation are challenging for several reasons, one of which is the difficulty in obtaining a reproducibly accurate real-time measurement of bacterial growth using insoluble substrates. Current methods suffer from several problems including (i) high background noise due to the insoluble material interspersed with cells, (ii) high consumable and reagent cost and (iii) significant time delay between sampling and data acquisition. A customizable substrate and cell separation device would provide an option to study bacterial growth using optical density measurements. To test this hypothesis we used 3-D printing to create biomass containment devices that allow interactionmore » between insoluble substrates and microbial cells but do not interfere with spectrophotometer measurements. Evaluation of materials available for 3-D printing indicated that UV-cured acrylic plastic was the best material, being superior to nylon or stainless steel when examined for heat tolerance, reactivity, and ability to be sterilized. Cost analysis of the 3-D printed devices indicated they are a competitive way to quantitate bacterial growth compared to viable cell counting or protein measurements, and experimental conditions were scalable over a 100-fold range. The presence of the devices did not alter growth phenotypes when using either soluble substrates or insoluble substrates. Furthermore, we applied biomass containment to characterize growth of Cellvibrio japonicus on authentic lignocellulose (non-pretreated corn stover), and found physiological evidence that xylan is a significant nutritional source despite an abundance of cellulose present.« less

  5. Main chain acid-degradable polymers for the delivery of bioactive materials

    DOEpatents

    Frechet, Jean M. J. [Oakland, CA; Standley, Stephany M [Evanston, IL; Jain, Rachna [Milpitas, CA; Lee, Cameron C [Cambridge, MA

    2012-03-20

    Novel main chain acid degradable polymer backbones and drug delivery systems comprised of materials capable of delivering bioactive materials to cells for use as vaccines or other therapeutic agents are described. The polymers are synthesized using monomers that contain acid-degradable linkages cleavable under mild acidic conditions. The main chain of the resulting polymers readily degrade into many small molecules at low pH, but remain relatively stable and intact at physiological pH. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and other sites of inflammation.

  6. New water-soluble metal working fluids additives from phosphonic acid derivatives for aluminum alloy materials.

    PubMed

    Kohara, Ichitaro; Tomoda, Hideyuki; Watanabe, Shoji

    2007-01-01

    Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short paper describes properties of new additives for water-soluble cutting fluids for aluminum alloy materials. Some alkyldiphosphonic acids were prepared with known method. Amine salts of these phosphonic acids showed anti-corrosion property for aluminum alloy materials. However, they have no hard water tolerance. Monoesters of octylphosphonic acid were prepared by the reaction of octylphosphonic acid dichloride with various alcohols in the presence of triethylamine. Amine salts of monoester of octylphosphonic acid with diethyleneglycol monomethyl ether, ethyleneglycol monomethyl ether and triethyleneglycol monomethyl ether showed both of a good anti-corrosion property for aluminum alloy materials and hard water tolerance.

  7. Chromatographic determination of amino acid enantiomers in beers and raw materials used for their manufacture.

    PubMed

    Erbe, T; Brückner, H

    2000-06-09

    Using gas chromatography (GC) on a chiral stationary phase, accompanied by high-performance liquid chromatography, beers and raw materials used for manufacturing (hops, barley grains, malts) were investigated for the pattern and quantities of amino acid enantiomers. Although L-amino acids were most abundant, certain D-amino acids were detected in all beers and most of the raw materials. Highest amounts of D-amino acids were detected in special beers such as Berliner Weisse that underwent bottle-conditioning with lactic cultures, and Belgian fruit beers produced by spontaneous fermentation. It is demonstrated that GC on chiral stationary phases is highly suitable for the quantitative determination of amino acid enantiomers in beers and raw materials used for their manufacture. Quantities, relative amounts and pattern of amino acid enantiomers can serve in particular as chiral markers for the authenticity of special beers.

  8. Concentration and Purification of Viruses by Adsorption to and Elution from Insoluble Polyelectrolytes

    PubMed Central

    Wallis, Craig; Melnick, Joseph L.; Fields, Joseph E.

    1971-01-01

    Acid-resistant, nonenveloped viruses belonging to the enterovirus, reovirus, and adenovirus groups were readily concentrated on PE60, an insoluble cross-linked polyelectrolyte based on isobutylene maleic anhydride. Hydrolysis of PE60 by NaOH increased its capacity to adsorb viruses. Hydrogen ion levels played an important role in virus concentration; optimal pH levels for maximal virus adsorption were between pH 3.0 and 4.5. Undiluted virus was easily concentrated from large volumes on PE60, and the adsorbed virus was readily eluted at pH 8 to 9. PMID:4325020

  9. Iron dissolution of dust source materials during simulated acidic processing: the effect of sulfuric, acetic, and oxalic acids.

    PubMed

    Chen, Haihan; Grassian, Vicki H

    2013-09-17

    Atmospheric organic acids potentially display different capacities in iron (Fe) mobilization from atmospheric dust compared with inorganic acids, but few measurements have been made on this comparison. We report here a laboratory investigation of Fe mobilization of coal fly ash, a representative Fe-containing anthropogenic aerosol, and Arizona test dust, a reference source material for mineral dust, in pH 2 sulfuric acid, acetic acid, and oxalic acid, respectively. The effects of pH and solar radiation on Fe dissolution have also been explored. The relative capacities of these three acids in Fe dissolution are in the order of oxalic acid > sulfuric acid > acetic acid. Oxalate forms mononuclear bidentate ligand with surface Fe and promotes Fe dissolution to the greatest extent. Photolysis of Fe-oxalate complexes further enhances Fe dissolution with the concomitant degradation of oxalate. These results suggest that ligand-promoted dissolution of Fe may play a more significant role in mobilizing Fe from atmospheric dust compared with proton-assisted processing. The role of atmospheric organic acids should be taken into account in global-biogeochemical modeling to better access dissolved atmospheric Fe deposition flux at the ocean surface.

  10. Aqueous alkali metal hydroxide insoluble cellulose ether membrane

    NASA Technical Reports Server (NTRS)

    Hoyt, H. E.; Pfluger, H. L. (Inventor)

    1969-01-01

    A membrane that is insoluble in an aqueous alkali metal hydroxide medium is described. The membrane is a resin which is a water-soluble C2-C4 hydroxyalkyl cellulose ether polymer and an insolubilizing agent for controlled water sorption, a dialytic and electrodialytic membrane. It is particularly useful as a separator between electrodes or plates in an alkaline storage battery.

  11. Battle of the starches: Insoluble versus soluble at the refinery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study using the USDA starch research method has been conducted to evaluate the effects of total, insoluble, and soluble starch on raw sugar filterability and viscosity in international carbonatation refineries. Raw sugar qualities, i.e., pol, color, % invert, ash, and dextran, were also studied in...

  12. Organic Analysis in the Miller Range 090657 CR2 Chondrite: Part 2 Amino Acid Analyses

    NASA Technical Reports Server (NTRS)

    Burton, A. S.; Cao, T.; Nakamura-Messenger, K.; Berger, E. L.; Messenger, S.; Clemett, S. J.; Aponte, J. C.; Elsila, J. E.

    2016-01-01

    Primitive carbonaceous chondrites contain a wide variety of organic material, ranging from soluble discrete molecules to insoluble, unstructured kerogen-like components, as well as structured nano-globules of macromolecular carbon. The relationship between the soluble organic molecules, macromolecular organic material, and host minerals are poorly understood. Due to the differences in extractability of soluble and insoluble organic materials, the analysis methods for each differ and are often performed independently. The combination of soluble and insoluble analyses, when performed concurrently, can provide a wider understanding of spatial distribution, and elemental, structural and isotopic composition of organic material in primitive meteorites. Using macroscale extraction and analysis techniques in combination with in situ microscale observation, we have been studying both insoluble and soluble organic material in the primitive CR2 chondrite Miller Range (MIL) 090657. In accompanying abstracts (Cao et al. and Messenger et al.) we discuss insoluble organic material in the samples. By performing the consortium studies, we aim to improve our understanding of the relationship between the meteorite minerals and the soluble and insoluble organic phases and to delineate which species formed within the meteorite and those that formed in nebular or presolar environments. In this abstract, we present the results of amino acid analyses of MIL 090657 by ultra performance liquid chromatography with fluorescence detection and quadrupole-time of flight mass spectrometry. Amino acids are of interest because they are essential to life on Earth, and because they are present in sufficient structural, enantiomeric and isotopic diversity to allow insights into early solar system chemical processes. Furthermore, these are among the most isotopically anomalous species, yet at least some fraction are thought to have formed by aqueously-mediated processes during parent body alteration.

  13. Repeated exposure of acidic beverages on esthetic restorative materials: An in-vitro surface microhardness study

    PubMed Central

    Sunny, Steffy M.; Rai, Kavita; Hegde, Amitha M.

    2016-01-01

    Background A manifold increase in the consumption of aerated beverages has witnessed a twin increase in tooth wear and raised demand for esthetic restorative materials. This study aimed to evaluate the surface microhardness changes of esthetic restorative materials following treatment with aerated beverages in an in-vitro situation. Material and Methods The initial surface microhardness of the restorative materials GC Fuji II LC, GC Fuji IX, Nano Glass ionomer, Resin and Nano composite was recorded. These materials were studied under 3 groups that included those exposed to the acidic beverages daily, weekly once in a month and those that had no exposures at all. The final surface microhardness of the materials was recorded following experimentation and was subjected to statistical comparisons. Results The restorative materials were compared for their surface microhardness changes following respective treatments using the T-test and One-way ANOVA analysis. Inter-comparisons between the groups showed statistical significance (p<.05), when treated with both the beverages. The five restorative materials revealed surface microhardness loss; the maximum reduction noticed with the Nano glass ionomer cement tested (p<.0005). Conclusions The surface microhardness of restorative materials markedly reduced upon repeated exposures with acidic beverages; the product with phosphoric acid producing the maximum surface microhardness loss. Key words:Restorative materials, acidic beverages, surface microhardness, resin composites, glass ionomers. PMID:27398183

  14. Improved grid materials for valve regulated lead acid batteries

    SciTech Connect

    Prengaman, R.D.

    1997-12-01

    During the last several years, research into lead alloys used as grid materials for VRLA batteries has led to a much better understanding of the roles of chemical composition and mechanical properties on the performance of the battery. VRLA batteries have suffered from premature capacity losses. It was believed that the loss was due to the absence of antimony in the battery grids. Recent work has indicated the beneficial effects of high tin contents on enhancing the conductivity of the grid-active material interface, increasing the mechanical properties, and reducing the corrosion rates of Pb-Ca-Sn alloys used in VRLA batteries. Additions of silver and controlled deformation processes enhance resistance to growth at elevated operating temperatures. The paper discusses how modification of composition and processing parameters can produce more stable, corrosion resistant, grid materials for VRLA batteries.

  15. The polymer-like organic material in the Orgueil meteorite

    NASA Technical Reports Server (NTRS)

    Bandurski, E. L.; Nagy, B.

    1976-01-01

    Results are reported for analysis of polymeric organic material contained in powder from the Orgueil chondrite, using a stepwise high-vacuum pyrolysis-gas chromatography-mass spectrometry technique. Pyrolysis products obtained include a series of alkanes and alkenes to C8, an extensive series of alkylbenzene isomers, thiophene, alkylthiophenes, benzothiophene, acetonitrile, acrylonitrile, benzonitrile, acetone, and phenol. Most of these products are shown to be similar both qualitatively and quantitatively to those previously obtained from solvent-extracted Allende powder, indicating a basically aromatic and heteroaromatic polymer matrix with short aliphatic bridges or side chains. The production of acrylonitrile, acetonitrile, and benzonitrile (common breakdown products of amino acids) from the insoluble organic material is taken to suggest that amino acids exist in an insoluble form, perhaps as peptides, in the meteorite's polymeric component. Similarities between the structure of the Orgueil polymeric material and terrestrial kerogen are discussed which raise the possibility that both might have been produced in part by similar reactions.

  16. A review on synthesis and characterization of solid acid materials for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Mohammad, Norsyahida; Mohamad, Abu Bakar; Kadhum, Abdul Amir H.; Loh, Kee Shyuan

    2016-08-01

    Solid acids emerged as an electrolyte material for application in fuel cells due to their high protonic conductivity and stability at high temperatures between 100 °C and 250 °C. This paper gives an overview of the different solid acid materials and their properties, such as high protonic conductivity and thermal stability, in relation to phase transitions and mechanisms of proton transport. Various solid acid synthesis methods including aqueous and dry mixing, electrospinning, sol-gel, impregnation and thin-film casting will be discussed, and the impact of synthesis methods on the properties of solid acids will be highlighted. The properties of solid acids synthesized as either single crystals and or polycrystalline powders were identified via X-ray diffraction, nuclear magnetic resonance, thermal analyses, optical microscopy and infrared spectroscopy. A selection of electrolyte-electrode assembly methods and the performance of solid acid fuel cell prototypes are also reviewed.

  17. Characterization of insoluble residues from the dissolution of irradiated (U,Pu)O{sub 2}

    SciTech Connect

    Goode, J.H.; Arwood, P.C.

    1983-05-01

    Hot-cell tests were conducted using (U,Pu)O{sub 2} fuels that had been irradiated to about 5.2 TJ/kg (U + Pu) [60 MWd/kg (U + Pu)] in an effort to characterize the insoluble residues that remained after the fuel pellets had been dissolved in HNO{sub 3} and in HNO{sub 3}-KF. The composition, particle size range, and density of the material were determined by newer analytical techniques, including spark-source mass spectrometry, neutron activation, scanning electron microscopy, and x-ray fluorescence, combined with older methods such as sedimentation and powder density by water displacement.

  18. Starch-lipid complexes: Interesting material and applications from amylose-fatty acid salt inclusion complexes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aqueous slurries of high amylose starch can be steam jet cooked and blended with aqueous solutions of fatty acid salts to generate materials that contain inclusion complexes between amylose and the fatty acid salt. These complexes are simply prepared on large scale using commercially available steam...

  19. An In Situ Method for Sizing Insoluble Residues in Precipitation

    NASA Astrophysics Data System (ADS)

    Axson, J. L.; Creamean, J.; Bondy, A. L.; Warner, K. Y.; Ault, A. P.

    2014-12-01

    Aerosols acting as cloud condensation nuclei (CCN) and ice nuclei (IN) play an important role in the climate effects of clouds. Wet deposition of these particles via rainout, washout, or cloud seeding is an important removal mechanism for aerosols in the atmosphere. Many of these particles, especially those that serve as IN, are insoluble and remain suspended after uptake within precipitating droplets/crystals as insoluble residues. While studies have measured the dissolved ions or mass of species within collected precipitation, no studies to date have quantified the number and size of insoluble residues. Herein, we demonstrate for the first time an in situ method for determining the number concentration, number size distribution, and surface area distribution of insoluble residues < 1 μm in diameter in samples of melted snow and rain. This work evaluates the use of nanoparticle tracking analysis (NTA), a new and novel technique for determining particle size distributions in a liquid medium, to determine in situ size distributions of insoluble residue particles in precipitation and evaluate this technique versus other analytical methods, including dynamic light scattering (DLS) and transmission electron microscopy (TEM). Number size distribution modes ranged from 80-150 nm and were strongly sample dependent. Surface area distribution modes ranged from 150-400 nm. Differences were observed between concentrations and size distributions for snow collected at different locations and elevations and between rain and melted snow. These differences can indicate changes in the insoluble residues that vary with ambient aerosol concentration, cloud microphysics, and meteorological dynamics. This method has great potential for improving our understanding of the properties of the particles nucleating droplets and crystals, the surface area available for reactions to occur, and the number of particles removed by scavenging. Additionally, the snow samples were further evaluated

  20. Synthesis, characterization and catalytic activity of acid-base bifunctional materials through protection of amino groups

    SciTech Connect

    Shao, Yanqiu; Liu, Heng; Yu, Xiaofang; Guan, Jingqi; Kan, Qiubin

    2012-03-15

    Graphical abstract: Acid-base bifunctional mesoporous material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized under low acidic medium through protection of amino groups. Highlights: Black-Right-Pointing-Pointer The acid-base bifunctional material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized through protection of amino groups. Black-Right-Pointing-Pointer The obtained bifunctional material was tested for aldol condensation. Black-Right-Pointing-Pointer The SO{sub 3}H-SBA-15-NH{sub 2} catalyst containing amine and sulfonic acid groups exhibited excellent acid-basic properties. -- Abstract: Acid-base bifunctional mesoporous material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized under low acidic medium through protection of amino groups. X-ray diffraction (XRD), N{sub 2} adsorption-desorption, transmission electron micrographs (TEM), back titration, {sup 13}C magic-angle spinning (MAS) NMR and {sup 29}Si magic-angle spinning (MAS) NMR were employed to characterize the synthesized materials. The obtained bifunctional material was tested for aldol condensation reaction between acetone and 4-nitrobenzaldehyde. Compared with monofunctional catalysts of SO{sub 3}H-SBA-15 and SBA-15-NH{sub 2}, the bifunctional sample of SO{sub 3}H-SBA-15-NH{sub 2} containing amine and sulfonic acid groups exhibited excellent acid-basic properties, which make it possess high activity for the aldol condensation.

  1. Peptide nucleic acid (PNA): a model structure for the primordial genetic material?

    PubMed

    Nielsen, P E

    1993-12-01

    It is proposed that the primordial genetic material could have been peptide nucleic acids, i.e., DNA analogues having a peptide backbone. PNA monomers based on the amino acid, alpha, gamma-diaminobutyric acid or ornithine are suggested as compounds that could have been formed in the prebiotic soup. Finally, the possibility of a PNA/RNA world is presented, in which PNA constitutes the stable genetic material, while RNA which may be polymerized using the PNA as template accounts for enzymatic activities including PNA replication.

  2. Soluble and insoluble fiber contents of some Cameroonian foodstuffs.

    PubMed

    Tanya, A K; Mbofung, C M; Keshinro, O O

    1997-01-01

    As a result of the lack of reliable data on the fiber content of African foodstuffs, a study to determine the dietary fiber contents (soluble, insoluble and total) on a dry weight basis of a selected variety of major Cameroonian foods was conducted. The influence of processing and preparation methods on the fiber content was also assessed. Vegetables were found to be the richest source of total dietary fiber (57%), followed by legumes and seeds (30%) and fruits (16.5%). Okro (Hibiscus esculenta), plantain (Musa paradisiaca) and beans (Phaseolus spp) showed varietal differences in their soluble and insoluble fiber content, while methods of processing and preparation significantly influenced the fiber content of cassava (Manihot esculenta), corn (Zea mays) and beans.

  3. Development and Evaluation of a Calibrator Material for Nucleic Acid-Based Assays for Diagnosing Aspergillosis

    PubMed Central

    Abdul-Ali, Deborah; Loeffler, Juergen; White, P. Lewis; Wickes, Brian; Herrera, Monica L.; Alexander, Barbara D.; Baden, Lindsey R.; Clancy, Cornelius; Denning, David; Nguyen, M. Hong; Sugrue, Michele; Wheat, L. Joseph; Wingard, John R.; Donnelly, J. Peter; Barnes, Rosemary; Patterson, Thomas F.; Caliendo, Angela M.

    2013-01-01

    Twelve laboratories evaluated candidate material for an Aspergillus DNA calibrator. The DNA material was quantified using limiting-dilution analysis; the mean concentration was determined to be 1.73 × 1010 units/ml. The calibrator can be used to standardize aspergillosis diagnostic assays which detect and/or quantify nucleic acid. PMID:23616459

  4. Binding and solubility of oleic acid to laboratory materials: A possible artifact

    SciTech Connect

    Mailman, D.; Rose, C. )

    1990-01-01

    The possibility that significant amounts of fatty acids were dissolved in or bound to the surfaces of common laboratory materials was examined. The uptake or adsorption of radioisotopically labeled oleic acid and cholic acid by plastic tubing of Tygon{trademark}, Teflon{trademark}, and polyethylene, and Pyrex{trademark}, and borosilicate glass, and steel was measured. {sup 3}H-oleic acid and {sup 14}C-cholic acid were used in the presence of different concentration of unlabeled oleic acid, cholic acid, and/or bovine serum albumin. Concentrations, composition, pH, and perfusion rates were varied. Relatively large amounts of oleic acid were lost by dissolving in plastic and adsorption to glass or metal. The degree of losses decreased in the presence of compounds in the perfusion solution which could bind or dissolve oleic acid. In contrast, cholic acid was not lost to plastic, glass or metal. The magnitude of and influence of perfusion rate, composition, pH, and sequence of perfusion solutions on oleic acid losses were sufficiently large that the results of certain studies, such as those of unstirred water layers or albumin-stimulated fatty acid uptake by hepatocytes may need to be reexamined.

  5. Insoluble polyelectrolyte and ion-exchange hollow fiber impregnated therewith

    NASA Technical Reports Server (NTRS)

    Rembaum, A. (Inventor)

    1977-01-01

    The number of quaternary sites and ion exchange capacity of a polyquaternary, cross linked, insoluble copolymer of a vinyl pyridine and a dihalo organic compound is increased by about 15-35% by reaction of the polymer with an amine followed by quaternization, if required. The polymer forms spontaneously in the presence of a substrate such as within the pores of a hollow fiber. The improved resin impregnated fiber may be utilized to remove ions from waste or process steams.

  6. An Insoluble Titanium-Lead Anode for Sulfate Electrolytes

    SciTech Connect

    Ferdman, Alla

    2005-05-11

    The project is devoted to the development of novel insoluble anodes for copper electrowinning and electrolytic manganese dioxide (EMD) production. The anodes are made of titanium-lead composite material produced by techniques of powder metallurgy, compaction of titanium powder, sintering and subsequent lead infiltration. The titanium-lead anode combines beneficial electrochemical behavior of a lead anode with high mechanical properties and corrosion resistance of a titanium anode. In the titanium-lead anode, the titanium stabilizes the lead, preventing it from spalling, and the lead sheathes the titanium, protecting it from passivation. Interconnections between manufacturing process, structure, composition and properties of the titanium-lead composite material were investigated. The material containing 20-30 vol.% of lead had optimal combination of mechanical and electrochemical properties. Optimal process parameters to manufacture the anodes were identified. Prototypes having optimized composition and structure were produced for testing in operating conditions of copper electrowinning and EMD production. Bench-scale, mini-pilot scale and pilot scale tests were performed. The test anodes were of both a plate design and a flow-through cylindrical design. The cylindrical anodes were composed of cylinders containing titanium inner rods and fitting over titanium-lead bushings. The cylindrical design allows the electrolyte to flow through the anode, which enhances diffusion of the electrolyte reactants. The cylindrical anodes demonstrate higher mass transport capabilities and increased electrical efficiency compared to the plate anodes. Copper electrowinning represents the primary target market for the titanium-lead anode. A full-size cylindrical anode performance in copper electrowinning conditions was monitored over a year. The test anode to cathode voltage was stable in the 1.8 to 2.0 volt range. Copper cathode morphology was very smooth and uniform. There was no

  7. Use of super acids to digest chrysotile and amosite asbestos in simple mixtures or matrices found in building materials compositions

    SciTech Connect

    Sugama, T.; Petrakis, L.; Webster, R.P.

    1999-12-21

    A composition for converting asbestos-containing material to environmentally benign components is provided. The composition comprises a fluoro acid decomposing agent which can be applied to either amosite-containing thermal insulation or chrysotile-containing fire-proof material or to any asbestos-containing material which includes of chrysotile and amosite asbestos. The fluoro acid decomposing agent includes FP{sub 0}(OH){sub 2}, hexafluorophosphoric acid, a mixture of hydrofluoric and phosphoric acid and a mixture of hexafluorophosphoric acid and phosphoric acid. A method for converting asbestos-containing material to environmentally benign components is also provided.

  8. Transmission of Soluble and Insoluble α-Synuclein to Mice

    PubMed Central

    Jones, Daryl R.; Delenclos, Marion; Baine, AnnMarie T.; DeTure, Michael; Murray, Melissa E.; Dickson, Dennis W.; McLean, Pamela J.

    2015-01-01

    The neurodegenerative synucleinopathies, which include Parkinson disease, multiple system atrophy, and Lewy body disease, are characterized by the presence of abundant neuronal inclusions called Lewy bodies and Lewy neurites. These disorders remain incurable and a greater understanding of the pathologic processes is needed for effective treatment strategies to be developed. Recent data suggest that pathogenic misfolding of the presynaptic protein, α-synuclein (α-syn), and subsequent aggregation and accumulation is fundamental to the disease process. It is hypothesized that the misfolded isoform is able to induce misfolding of normal endogenous α-syn, much like what occurs in the prion diseases. Recent work highlighting the seeding effect of pathogenic α-syn has largely focused on the detergent-insoluble species of the protein. In this study we performed intracerebral inoculations of the sarkosyl-insoluble or sarkosyl-soluble fractions of human Lewy body disease brain homogenate and show that both fractions induce CNS pathology in mice at 4 months post-injection. Disease-associated deposits accumulated both near and distal to the site of the injection suggesting a cell-to-cell spread via recruitment of α-syn. These results provide further insight into the prion-like mechanisms of α-syn and suggest that disease-associated α-syn is not homogenous within a single patient but might exist in both soluble and insoluble isoforms. PMID:26574670

  9. Tracking of Drug Release and Material Fate for Naturally Derived Omega-3 Fatty Acid Biomaterials.

    PubMed

    Faucher, Keith M; Artzi, Natalie; Beck, Moshe; Beckerman, Rita; Moodie, Geoff; Albergo, Theresa; Conroy, Suzanne; Dale, Alicia; Corbeil, Scott; Martakos, Paul; Edelman, Elazer R

    2016-03-01

    In vitro and in vivo studies were conducted on omega-3 fatty acid-derived biomaterials to determine their utility as an implantable material for adhesion prevention following soft tissue hernia repair and as a means to allow for the local delivery of antimicrobial or antibiofilm agents. Naturally derived biomaterials offer several advantages over synthetic materials in the field of medical device development. These advantages include enhanced biocompatibility, elimination of risks posed by the presence of toxic catalysts and chemical crosslinking agents, and derivation from renewable resources. Omega-3 fatty acids are readily available from fish and plant sources and can be used to create implantable biomaterials either as a stand-alone device or as a device coating that can be utilized in local drug delivery applications. In-depth characterization of material erosion degradation over time using non-destructive imaging and chemical characterization techniques provided mechanistic insight into material structure: function relationship. This in turn guided rational tailoring of the material based on varying fatty acid composition to control material residence time and hence drug release. These studies demonstrate the utility of omega-3 fatty acid derived biomaterials as an absorbable material for soft tissue hernia repair and drug delivery applications.

  10. 21 CFR 177.1400 - Hydroxyethyl cellulose film, water-insoluble.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Hydroxyethyl cellulose film, water-insoluble. 177... cellulose film, water-insoluble. Water-insoluble hydroxyethyl cellulose film may be safely used for... cellulose film consists of a base sheet manufactured by the ethoxylation of cellulose under...

  11. 21 CFR 177.1400 - Hydroxyethyl cellulose film, water-insoluble.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Hydroxyethyl cellulose film, water-insoluble. 177... cellulose film, water-insoluble. Water-insoluble hydroxyethyl cellulose film may be safely used for... cellulose film consists of a base sheet manufactured by the ethoxylation of cellulose under...

  12. 21 CFR 177.1400 - Hydroxyethyl cellulose film, water-insoluble.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Hydroxyethyl cellulose film, water-insoluble. 177... cellulose film, water-insoluble. Water-insoluble hydroxyethyl cellulose film may be safely used for... cellulose film consists of a base sheet manufactured by the ethoxylation of cellulose under...

  13. 21 CFR 177.1400 - Hydroxyethyl cellulose film, water-insoluble.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Hydroxyethyl cellulose film, water-insoluble. 177... Repeated Use Food Contact Surfaces § 177.1400 Hydroxyethyl cellulose film, water-insoluble. Water-insoluble hydroxyethyl cellulose film may be safely used for packaging food in accordance with the following...

  14. 21 CFR 177.1400 - Hydroxyethyl cellulose film, water-insoluble.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Hydroxyethyl cellulose film, water-insoluble. 177... cellulose film, water-insoluble. Water-insoluble hydroxyethyl cellulose film may be safely used for... cellulose film consists of a base sheet manufactured by the ethoxylation of cellulose under...

  15. Testing the Role of Silicic Acid and Bioorganic Materials in the Formation of Rock Coatings

    SciTech Connect

    Kolb, Vera; Philip, Ajish I.; Perry, Randall S.

    2004-12-01

    Silica, amino acids, and DNA were recently discovered in desert varnish. In this work we experimentally test the proposed role of silicic acid and bio-chemicals in the formation of desert varnish and other rock coatings. We have developed a protocol in which hte rocks were treated with a mixture of silicic acid, sugars, amino acids, metals and clays, under the influence of heat and UV light. This protocol reflects the proposed mechanism of hte polymerization of silicic acid with the bioorganic materials, and the laboratory model for the natural conditions under which the desert varnish is formed. Our experiments produced coatings with a hardness and morphology that resemble the nature ones. These results provide a support for the role of silicic acid in the formation of rock coatings. Since the hard silica-based coatings preserve organic compounds in them, they may serve as a biosignature for life, here or possibly Mars.

  16. Electrode materials for hydrobromic acid electrolysis in Texas Instruments' solar chemical converter

    SciTech Connect

    Luttmer, J.D.; Konrad, D.; Trachtenberg, I.

    1985-05-01

    Texas Instruments has developed a solar chemical converter (SCC) which converts solar energy into chemical energy via the electrolysis of hydrobromic acid. Various materials were evaluated as anodes and cathodes for the electrolysis of the acid. Emphasis was placed on obtaining low overvoltage electrodes with good long-term stability. Sputtered platinum-iridium thin films were identified as the best choice as the cathode material, and sputtered iridium and iridium oxide thin films were identified as the best choice as anode materials. Electrochemical measurements indicate that low overvoltage losses are encountered on these materials at operating current densitities in the SCC. Accelerated corrosion tests of the materials predict acceptable electrode stability for 20 years in an environment representative of onthe-roof service.

  17. Artificially induced polymer particle erosion of oral hydrocolloid systems by the addition of insoluble cellulose fibres to fibre-free methylhydroxy ethylcellulose (MHEC).

    PubMed

    Freichel, Oliver L; Lippold, Bernhard C

    2004-05-01

    The erosion-controlled drug release from different methylhydroxy ethylcellulose (MHEC) hydrocolloid tablets was examined. The special polymer particle erosion mechanism, which is nearly independent from the hydrodynamic conditions in the dissolution medium, could be attributed to the existence of insoluble fibres within the polymer material. They could be identified via microscopic analysis. The study presents a precipitation method, which guarantees an appropriate incorporation of insoluble microcrystalline cellulose fibres into fibre-free MHEC material. This method leads to a manufacturing process for polymer particle erosion-controlled hydrocolloid systems with the possibility to adjust the drug release rate.

  18. Physiological function of insoluble dietary fiber prepared from exploded oak wood (Quercus mongolica).

    PubMed

    Yang, Jae-Kyung; Choi, Myung-Suk; Kim, Chang-Joon; Shin, Yong-Seung; Han, Dae-Yong; Han, Sang-Woo; Lim, Bu-Kug; Lee, Jong-Yoon; Rhee, Soon-Jae; Kim, Eun-Hee; Kim, Gon-Sup

    2006-01-01

    This study investigated the production of insoluble dietary fiber using exploded and chemically treated oak wood (Quercus mongolica) and the physiological functions of prepared insoluble dietary fiber in laboratory animals. To produce high quality insoluble dietary fiber, the steam explosion treatment was performed at 25 kgf/cm2 pressure for 6 minutes. In the chemical analysis of insoluble dietary fiber, exploded oak wood was pretreated by 1% sodium hydroxide solution. The insoluble dietary fiber contained 7.6% residual lignin and 61.7% of alpha-cellulose. In order to compare the physiological functions of prepared insoluble dietary fiber with those of commercial insoluble dietary fiber, Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal diet and five high cholesterol diets, containing 1% cholesterol. The high cholesterol diet groups were classified as the fiber-free diet (FF group), 5% commercial alpha-cellulose diet group (5C group), 10% commercial alpha-cellulose group (10C group), 5% insoluble dietary fiber group (5M group) and 10% insoluble dietary fiber group (10M group). Food intake, weight gain and food efficiency ratio in high cholesterol groups were significantly higher than those of the normal group, but there were no significant differences among the high cholesterol diet groups. In addition, there were no significant differences in the weights of liver, kidney and small intestine in insoluble dietary fiber-supplemented groups. Cecum weights in all insoluble dietary fiber groups were significantly higher than those of the FF group. There were no significant differences in the activities of the glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) among the insoluble dietary fiber-supplemented groups. In conclusion, the prepared insoluble dietary fiber and the commercially available insoluble fiber showed the same physiological effects. Moreover, the preparation method for the insoluble dietary

  19. Preparation, characterization and catalytic properties of MCM-48 supported tungstophosphoric acid mesoporous materials for green synthesis of benzoic acid

    SciTech Connect

    Wu, Hai-Yan; Zhang, Xiao-Li; Chen, Xi; Chen, Ya; Zheng, Xiu-Cheng

    2014-03-15

    MCM-48 and tungstophosphoric acid (HPW) were prepared and applied for the synthesis of HPW/MCM-48 mesoporous materials. The characterization results showed that HPW/MCM-48 obtained retained the typical mesopore structure of MCM-48, and the textural parameters decreased with the increase loading of HPW. The catalytic oxidation results of benzyl alcohol and benzaldehyde with 30% H{sub 2}O{sub 2} indicated that HPW/MCM-48 was an efficient catalyst for the green synthesis of benzoic acid. Furthermore, 35 wt% HPW/MCM-48 sample showed the highest activity under the reaction conditions. Highlights: • 5–45 wt% HPW/MCM-48 mesoporous catalysts were prepared and characterized. • Their catalytic activities for the green synthesis of benzoic acid were investigated. • HPW/MCM-48 was approved to be an efficient catalyst. • 5 wt% HPW/MCM-48 exhibited the highest catalytic activity.

  20. Determination of insoluble soap in agricultural soil and sewage sludge samples by liquid chromatography with ultraviolet detection.

    PubMed

    Cantarero, Samuel; Zafra-Gómez, Alberto; Ballesteros, Oscar; Navalón, Alberto; Vílchez, José L; Crovetto, Guillermo; Verge, Coral; de Ferrer, Juan A

    2010-11-01

    We have developed a new analytical procedure for determining insoluble Ca and Mg fatty acid salts (soaps) in agricultural soil and sewage sludge samples. The number of analytical methodologies that focus in the determination of insoluble soap salts in different environmental compartments is very limited. In this work, we propose a methodology that involves a sample clean-up step with petroleum ether to remove soluble salts and a conversion of Ca and Mg insoluble salts into soluble potassium salts using tripotassium ethylenediaminetetraacetate salt and potassium carbonate, followed by the extraction of analytes from the samples using microwave-assisted extraction with methanol. An improved esterification procedure using 2,4-dibromoacetophenone before the liquid chromatography with ultraviolet detection analysis also has been developed. The absence of matrix effect was demonstrated with two fatty acid Ca salts that are not commercial and are never detected in natural samples (C₁₃:₀ and C₁₇:₀). Therefore, it was possible to evaluate the matrix effect because both standards have similar environmental behavior (adsorption and precipitation) to commercial soaps (C₁₀:₀) to C₁₈:₀). We also studied the effect of the different variables on the clean-up, the conversion of Ca soap, and the extraction and derivatization procedures. The quantification limits found ranged from 0.4 to 0.8 mg/kg. The proposed method was satisfactorily applied for the development of a study on soap behavior in agricultural soil and sewage sludge samples.

  1. Development of Stable Solidification Method for Insoluble Ferrocyanides-13170

    SciTech Connect

    Ikarashi, Yuki; Masud, Rana Syed; Mimura, Hitoshi; Ishizaki, Eiji; Matsukura, Minoru

    2013-07-01

    The development of stable solidification method of insoluble ferrocyanides sludge is an important subject for the safety decontamination in Fukushima NPP-1. By using the excellent immobilizing properties of zeolites such as gas trapping ability and self-sintering properties, the stable solidification of insoluble ferrocyanides was accomplished. The immobilization ratio of Cs for K{sub 2}[CoFe(CN){sub 6}].nH{sub 2}O saturated with Cs{sup +} ions (Cs{sub 2}[CoFe(CN){sub 6}].nH{sub 2}O) was estimated to be less than 0.1% above 1,000 deg. C; the adsorbed Cs{sup +} ions are completely volatilized. In contrast, the novel stable solid form was produced by the press-sintering of the mixture of Cs{sub 2}[CoFe(CN){sub 6}].nH{sub 2}O and zeolites at higher temperature of 1,000 deg. C and 1,100 deg. C; Cs volatilization and cyanide release were completely depressed. The immobilization ratio of Cs, under the mixing conditions of Cs{sub 2}[CoFe(CN){sub 6}].nH{sub 2}O:CP= 1:1 and calcining temperature: 1,000 deg. C, was estimated to be nearly 100%. As for the kinds of zeolites, natural mordenite (NM), clinoptilolite (CP) and Chabazite tended to have higher immobilization ratio compared to zeolite A. This may be due to the difference in the phase transformation between natural zeolites and synthetic zeolite A. In the case of the composites (K{sub 2-X}Ni{sub X/2}[NiFe(CN){sub 6}].nH{sub 2}O loaded natural mordenite), relatively high immobilization ratio of Cs was also obtained. This method using zeolite matrices can be applied to the stable solidification of the solid wastes of insoluble ferrocyanides sludge. (authors)

  2. Novel sol-gel synthesis of acidic MgF(2-x)(OH)(x) materials.

    PubMed

    Wuttke, Stefan; Coman, Simona M; Scholz, Gudrun; Kirmse, Holm; Vimont, Alexandré; Daturi, Maro; Schroeder, Sven L M; Kemnitz, Erhard

    2008-01-01

    Novel magnesium fluorides have been prepared by a new fluorolytic sol-gel synthesis for fluoride materials based on aqueous HF. By changing the amount of water at constant stoichiometric amount of HF, it is possible to tune the surface acidity of the resulting partly hydroxylated magnesium fluorides. These materials possess medium-strength Lewis acid sites and, by increasing the amount of water, Brønsted acid sites as well. Magnesium hydroxyl groups normally have a basic nature and only with this new synthetic route is it possible to create Brønsted acidic magnesium hydroxyl groups. XRD, MAS NMR, TEM, thermal analysis, and elemental analysis have been applied to study the structure, composition, and thermal behaviour of the bulk materials. XPS measurements, FTIR with probe molecules, and the determination of N(2)/Ar adsorption-desorption isotherms have been carried out to investigate the surface properties. Furthermore, activity data have indicated that the tuning of the acidic properties makes these materials versatile catalysts for different classes of reactions, such as the synthesis of (all-rac)-[alpha]-tocopherol through the condensation of 2,3,6-trimethylhydroquinone (TMHQ) with isophytol (IP).

  3. Characterization of microcrystalline cellulose prepared from lignocellulosic materials. Part I. Acid catalyzed hydrolysis.

    PubMed

    Adel, Abeer M; Abd El-Wahab, Zeinab H; Ibrahim, Atef A; Al-Shemy, Mona T

    2010-06-01

    Rice hulls (RH) and bean hulls (BH) were subjected to prehydrolysis treatments, to define the optimum conditions for producing a high percentage of hydrolyzed hemicellulose with a small or moderate degradation of the cellulosic portion. The hydrolysis experiments were performed using hydrochloric and sulfuric acids in concentrations ranging from (0.5 to 5)% (w/w) at 120 degrees C for 90 min and 10% consistency. The effects of different temperatures (80 to 120 degrees C) and time (30 to 120 min) on acid hydrolysis of lignocellulosic materials were recorded. It was found that, the optimum condition to hydrolyze the lignocellulosic materials (RH) and (BH) are 2% (w/w) of mineral acid at 120 degrees C for 90 min and 10% consistency. The cellulose crystallinity index in the different types of lignocellulosic materials with and without acid treatment, were increased from 0.32 to 0.46 in case of RH and from 0.43 to 0.61 in case of BH. Due to the lignin depolymerization during the pretreatment process, the relative absorbency of the methoxyl group and the aromatic rings bands were lowered for the pretreated than the untreated lignocellulosic materials. Also, the band at 1730 cm(-1) which is attributed to carbonyl groups of uronic acids was lowered due the hemicellulose hydrolysis.

  4. Marine bacterioplankton can increase evaporation and gas transfer bymetabolizing insoluble surfactants from the air-seawater interface.

    PubMed

    Salter, Ian; Zubkov, Mikhail V; Warwick, Phil E; Burkill, Peter H

    2009-05-01

    Hydrophobic surfactants at the air-sea interface can retard evaporative and gaseous exchange between the atmosphere and the ocean.While numerous studies have examined the metabolic role of bacterioneuston at the air-sea interface, the interactions between hydrophobic surfactants and bacterioplankton are not well constrained. A novel experimental design was developed, using Vibrio natriegens and (3)H-labelled hexadecanoic acid tracer, to determine how the bacterial metabolism of fatty acids affects evaporative fluxes. In abiotic systems, >92% of the added hexadecanoic acid remained at the air-water interface. In contrast, the presence of V. natriegens cells draws down insoluble hexadecanoic acid from the air-water interface as an exponential function of time. The exponents characterizing the removal of hexadecanoic acid from the interface co-vary with the concentration of V. natriegens cells in the underlying water, with the largest exponent corresponding to the highest cell abundance. Radiochemical budgets show that evaporative fluxes from the system are linearly proportional to the quantity of hexadecanoic acid at the interface. Thus, bacterioplankton could influence the rate of evaporation and gas transfer in the ocean through the metabolism of otherwise insoluble surfactants.

  5. Peptide nucleic acid (PNA): A model structure for the primordial genetic material?

    NASA Astrophysics Data System (ADS)

    Nielsen, Peter Egil

    1993-12-01

    It is proposed that the primordial genetic material could have been peptide nucleic aicds,i.e., DNA analogues having a peptide backbone. PNA momomers based on the amino acid, α, γ-diaminobutyric acid or ornithine are suggested as compounds that could have been formed in the prebiotic soup. Finally, the possibility of a PNA/RNA world is presented, in which PNA constitutes the stable genetic material, while RNA which may be polymerized using the PNA as template accounts for enzymatic activities including PNA replication.

  6. Microbial production of specialty organic acids from renewable and waste materials.

    PubMed

    Alonso, Saúl; Rendueles, Manuel; Díaz, Mario

    2015-01-01

    Microbial production of organic acids has become a fast-moving field due to the increasing role of these compounds as platform chemicals. In recent years, the portfolio of specialty fermentation-derived carboxylic acids has increased considerably, including the production of glyceric, glucaric, succinic, butyric, xylonic, fumaric, malic, itaconic, lactobionic, propionic and adipic acid through innovative fermentation strategies. This review summarizes recent trends in the use of novel microbial platforms as well as renewable and waste materials for efficient and cost-effective bio-based production of emerging high-value organic acids. Advances in the development of robust and efficient microbial bioprocesses for producing carboxylic acids from low-cost feedstocks are also discussed. The industrial market scenario is also reviewed, including the latest information on the stage of development for producing these emerging bio-products via large-scale fermentation.

  7. Antimicrobial activity of transition metal acid MoO(3) prevents microbial growth on material surfaces.

    PubMed

    Zollfrank, Cordt; Gutbrod, Kai; Wechsler, Peter; Guggenbichler, Josef Peter

    2012-01-01

    Serious infectious complications of patients in healthcare settings are often transmitted by materials and devices colonised by microorganisms (nosocomial infections). Current strategies to generate material surfaces with an antimicrobial activity suffer from the consumption of the antimicrobial agent and emerging multidrug-resistant pathogens amongst others. Consequently, materials surfaces exhibiting a permanent antimicrobial activity without the risk of generating resistant microorganisms are desirable. This publication reports on the extraordinary efficient antimicrobial properties of transition metal acids such as molybdic acid (H(2)MoO(4)), which is based on molybdenum trioxide (MoO(3)). The modification of various materials (e.g. polymers, metals) with MoO(3) particles or sol-gel derived coatings showed that the modified materials surfaces were practically free of microorganisms six hours after contamination with infectious agents. The antimicrobial activity is based on the formation of an acidic surface deteriorating cell growth and proliferation. The application of transition metal acids as antimicrobial surface agents is an innovative approach to prevent the dissemination of microorganisms in healthcare units and public environments.

  8. Surface fractal dimension, water adsorption efficiency, and cloud nucleation activity of insoluble aerosol

    PubMed Central

    Laaksonen, Ari; Malila, Jussi; Nenes, Athanasios; Hung, Hui-Ming; Chen, Jen-Ping

    2016-01-01

    Surface porosity affects the ability of a substance to adsorb gases. The surface fractal dimension D is a measure that indicates the amount that a surface fills a space, and can thereby be used to characterize the surface porosity. Here we propose a new method for determining D, based on measuring both the water vapour adsorption isotherm of a given substance, and its ability to act as a cloud condensation nucleus when introduced to humidified air in aerosol form. We show that our method agrees well with previous methods based on measurement of nitrogen adsorption. Besides proving the usefulness of the new method for general surface characterization of materials, our results show that the surface fractal dimension is an important determinant in cloud drop formation on water insoluble particles. We suggest that a closure can be obtained between experimental critical supersaturation for cloud drop activation and that calculated based on water adsorption data, if the latter is corrected using the surface fractal dimension of the insoluble cloud nucleus. PMID:27138171

  9. High-throughput Screening of Carbohydrate-degrading Enzymes Using Novel Insoluble Chromogenic Substrate Assay Kits

    PubMed Central

    Willats, William G. T.

    2016-01-01

    Carbohydrates active enzymes (CAZymes) have multiple roles in vivo and are widely used for industrial processing in the biofuel, textile, detergent, paper and food industries. A deeper understanding of CAZymes is important from both fundamental biology and industrial standpoints. Vast numbers of CAZymes exist in nature (especially in microorganisms) and hundreds of thousands have been cataloged and described in the carbohydrate active enzyme database (CAZy). However, the rate of discovery of putative enzymes has outstripped our ability to biochemically characterize their activities. One reason for this is that advances in genome and transcriptome sequencing, together with associated bioinformatics tools allow for rapid identification of candidate CAZymes, but technology for determining an enzyme's biochemical characteristics has advanced more slowly. To address this technology gap, a novel high-throughput assay kit based on insoluble chromogenic substrates is described here. Two distinct substrate types were produced: Chromogenic Polymer Hydrogel (CPH) substrates (made from purified polysaccharides and proteins) and Insoluble Chromogenic Biomass (ICB) substrates (made from complex biomass materials). Both CPH and ICB substrates are provided in a 96-well high-throughput assay system. The CPH substrates can be made in four different colors, enabling them to be mixed together and thus increasing assay throughput. The protocol describes a 96-well plate assay and illustrates how this assay can be used for screening the activities of enzymes, enzyme cocktails, and broths. PMID:27684747

  10. Nucleation and growth of intragranular defect and insoluble atom clusters in nuclear oxide fuels

    NASA Astrophysics Data System (ADS)

    Garcia, P.; Martin, G.; Sabathier, C.; Carlot, G.; Michel, A.; Martin, P.; Dorado, B.; Freyss, M.; Bertolus, M.; Skorek, R.; Noirot, J.; Noirot, L.; Kaitasov, O.; Maillard, S.

    2012-04-01

    Uranium and plutonium oxides are subjected to high levels of radiation damage due to the slowing of fission fragments. In addition the composition of the material evolves over time as a result of fission events. Rare gases which constitute an abundant class of fission products are particularly insoluble and therefore tend either to be released from the fuel or form small nanometre size clusters. Bubbles are liable to grow and become trapping sites for migrating defects or other insoluble atoms. Interactions between migrating atoms, defects and existing clusters will determine the rate and extent to which clusters grow. Because the transfer of gas from within the grain to the grain boundaries is thought of as being the rate limiting process for fission gas release, a review of phenomena occurring on the sub-grain scale is carried out. The microstructural modifications induced by neutron irradiations of UO2 fuels are discussed with an emphasis on their relation to fission gas release. Based mainly on TEM studies, the phenomena which are usually taken into account in fission gas behaviour models are looked at and the limitations of these models outlined. More recent experimental and modelling approaches involving ion-irradiation experiments and atomic scale modelling are presented. It is shown that combining these approaches may lead, despite the complexity inherent to the system, to a better understanding of basic radiation induced microstructural changes, clustering events, and rare gas behaviour.

  11. Comparative toxicity and carcinogenicity of soluble and insoluble cobalt compounds.

    PubMed

    Behl, Mamta; Stout, Matthew D; Herbert, Ronald A; Dill, Jeffrey A; Baker, Gregory L; Hayden, Barry K; Roycroft, Joseph H; Bucher, John R; Hooth, Michelle J

    2015-07-03

    Occupational exposure to cobalt is of widespread concern due to its use in a variety of industrial processes and the occurrence of occupational disease. Due to the lack of toxicity and carcinogenicity data following exposure to cobalt, and questions regarding bioavailability following exposure to different forms of cobalt, the NTP conducted two chronic inhalation exposure studies in rats and mice, one on soluble cobalt sulfate heptahydrate, and a more recent study on insoluble cobalt metal. Herein, we compare and contrast the toxicity profiles following whole-body inhalation exposures to these two forms of cobalt. In general, both forms were genotoxic in the Salmonella T98 strain in the absence of effects on micronuclei. The major sites of toxicity and carcinogenicity in both chronic inhalation studies were the respiratory tract in rats and mice, and the adrenal gland in rats. In addition, there were distinct sites of toxicity and carcinogenicity noted following exposure to cobalt metal. In rats, carcinogenicity was observed in the blood, and pancreas, and toxicity was observed in the testes of rats and mice. Taken together, these findings suggest that both forms of cobalt, soluble and insoluble, appear to be multi-site rodent carcinogens following inhalation exposure.

  12. Insoluble and soluble roasted walnut proteins retain antibody reactivity.

    PubMed

    Downs, Melanie L; Simpson, Angela; Custovic, Adnan; Semic-Jusufagic, Aida; Bartra, Joan; Fernandez-Rivas, Montserrat; Taylor, Steve L; Baumert, Joseph L; Mills, E N Clare

    2016-03-01

    Thermal processing techniques commonly used during food production have the potential to impact food allergens by inducing physical and/or chemical changes to the proteins. English walnuts (Juglans regia) are among the most commonly allergenic tree nuts, but little information is available regarding how walnut allergens respond to thermal processing. This study evaluated the effects of dry roasting (132 or 180°C for 5, 10, or 20min) on the solubility and immunoreactivity of walnut proteins. A dramatic decrease in walnut protein solubility was observed following dry roasting at 180°C for 20min. However, both the soluble and insoluble protein fractions from roasted walnuts maintained substantial amounts of IgG immunoreactivity (using anti-raw and anti-roasted walnut antisera), with similar patterns of reactivity observed for human IgE from walnut-allergic individuals. Thus, walnut proteins are relatively stable under certain thermal processing conditions, and IgE reactivity remains present even when insoluble aggregates are formed.

  13. Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces

    NASA Technical Reports Server (NTRS)

    Dussinger, Peter M.; Lindemuth, James E.

    1997-01-01

    The principal objective of this Phase 2 SBIR program was to develop and demonstrate a practically insoluble coating for nickel-based superalloys for Stirling engine heat pipe applications. Specific technical objectives of the program were: (1) Determine the solubility corrosion rates for Nickel 200, Inconel 718, and Udimet 72OLI in a simulated Stirling engine heat pipe environment, (2) Develop coating processes and techniques for capillary groove and screen wick structures, (3) Evaluate the durability and solubility corrosion rates for capillary groove and screen wick structures coated with an insoluble coating in cylindrical heat pipes operating under Stirling engine conditions, and (4) Design and fabricate a coated full-scale, partial segment of the current Stirling engine heat pipe for the Stirling Space Power Convertor program. The work effort successfully demonstrated a two-step nickel aluminide coating process for groove wick structures and interior wall surfaces in contact with liquid metals; demonstrated a one-step nickel aluminide coating process for nickel screen wick structures; and developed and demonstrated a two-step aluminum-to-nickel aluminide coating process for nickel screen wick structures. In addition, the full-scale, partial segment was fabricated and the interior surfaces and wick structures were coated. The heat pipe was charged with sodium, processed, and scheduled to be life tested for up to ten years as a Phase 3 effort.

  14. Assessment of surface acidity in mesoporous materials containing aluminum and titanium

    NASA Astrophysics Data System (ADS)

    Araújo, Rinaldo S.; Maia, Débora A. S.; Azevedo, Diana C. S.; Cavalcante, Célio L., Jr.; Rodríguez-Castellón, E.; Jimenez-Lopez, A.

    2009-04-01

    The surface acidity of mesoporous molecular sieves of aluminum and titanium was evaluated using four different techniques: n-butylamine volumetry, cyclohexylamine thermodesorption, temperature-programmed desorption of ammonia and adsorption of pyridine. The nature, strength and concentration of the acid sites were determined and correlated to the results of a probe reaction of anthracene oxidation to 9,10-anthraquinone (in liquid phase). In general, the surface acidity was highly influenced by the nature, location and coordination of the metal species (Al and Ti) in the mesoporous samples. Moderate to strong Brönsted acid sites were identified for the Al-MCM-41 sample in a large temperature range. For mesoporous materials containing Ti, the acidity was represented by a combination of weak to moderate Brönsted and Lewis acid sites. The Ti-HMS sample exhibits a higher acidity of moderate strength together with a well-balanced concentration of Brönsted and Lewis acid sites, which enhanced both conversion and selectivity in the oxidation reaction of anthracene.

  15. EVALUATION OF POLY(LACTIC ACID) AND AGRICULTURAL COPRODUCTS AS GREEN COMPOSITE MATERIALS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Green composite materials of poly(lactic acid)(PLA) and agricultural coproducts such as sugar beet pulp(SBP), cuphea, lesquerella, and milkweed were compounded using a twin-screw extruder, molded by injection molding and evaluated for structural and mechanical properties using acoustic emission and ...

  16. Modification of wheat gluten with citric acid to produce superabsorbent materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat gluten was reacted with citric acid to produce natural superabsorbent materials able to absorb up to 78 times its weight in water. The properties of the modified gluten samples were characterized using Fourier Transform Infra-red (FTIR) spectroscopy, thermogravimetric analysis, and water uptak...

  17. Long-term stability of earthen materials in contact with acidic tailings solutions

    SciTech Connect

    Peterson, S.R.; Erikson, R.L.; Gee, G.W.

    1982-11-01

    The objectives of the studies documented in this report were to use experimental and geochemical computer modeling tools to assess the long-term environmental impact of leachate movement from acidic uranium mill tailings. Liner failure (i.e., an increase in the permeability of the liner material) was not found to be a problem when various acidic tailings solutions leached through liner materials for periods up to 3 years. On the contrary, materials that contained over 30% clay showed a decrease in permeability with time in the laboratory columns. The high clay materials tested appear suitable for lining tailings impoundment ponds. The decreases in permeability are attributed to pore plugging resulting from the precipitation of minerals and solids. This precipitation takes place due to the increase in pH of the tailings solution brought about by the buffering capacity of the soil. Geochemical modeling predicts, and x-ray characterization confirms, that precipitation of solids from solution is occurring in the acidic tailings solution/liner interactions studied. In conclusion the same mineralogical changes and contaminant reactions predicted by geochemical modeling and observed in laboratory studies were found at a drained evaporation pond (Lucky Mc in Wyoming) with a 4 year history of acid attack.

  18. The influence of acid treatments over vermiculite based material as adsorbent for cationic textile dyestuffs.

    PubMed

    Stawiński, Wojciech; Freitas, Olga; Chmielarz, Lucjan; Węgrzyn, Agnieszka; Komędera, Kamila; Błachowski, Artur; Figueiredo, Sónia

    2016-06-01

    The influence of different acid treatments over vermiculite was evaluated. Equilibrium, kinetic and column studies have been conducted. The results showed that vermiculite first treated with nitric acid and then with citric acid has higher adsorption capacity, presenting maximum adsorption capacities in column experiments: for Astrazon Red (AR), 100.8 ± 0.8 mg g(-1) and 54 ± 1 mg g(-1) for modified and raw material, respectively; for Methylene Blue (MB) 150 ± 4 mg g(-1) and 55 ± 2 mg g(-1) for modified and raw material, respectively. Materials characterization by X-ray diffraction, UV-vis-diffuse reflectance spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, X-ray fluorescence, N2 adsorption and CEC determination, has been performed. The results suggest the existence of exchange of interlayer cations, leaching of metals from vermiculite's sheets and formation of an amorphous phase in the material. Adsorption follows pseudo 2(nd) order model kinetics for both dyestuffs and equilibrium occurs accordingly to Langmuir's model for AR and Freundlich's model for MB. In column systems Yan's model is the best fit. The enhanced properties of acid treated vermiculite offer new perspectives for the use of this adsorbent in wastewater treatment.

  19. Limestone dissolution induced by fungal mycelia, acidic materials, and carbonic anhydrase from fungi.

    PubMed

    Li, Wei; Zhou, Peng-Peng; Jia, Li-Ping; Yu, Long-Jiang; Li, Xue-Li; Zhu, Min

    2009-01-01

    Microorganisms influence the dissolution of a number of minerals. Limestone is one of the most abundant rock types in karst areas, and is predominantly calcium carbonate. Two types of experimental systems were designed in this paper, to make comparisons of limestone dissolution rate among the acidic materials and extracellular carbonic anhydrase (CA) excreted by fungi and the enwrapping effect of fungal mycelia. One was the simulated experimental system containing microorganisms. Another was the simulated experimental system without microorganisms. Results of previous experiment indicated that the acidic materials and CA like enzymatic materials excreted by fungi and the enwrapping effect of fungal mycelia were important factors influencing limestone dissolution. In the three factors mentioned above, the dissolution effect was mycelia enwraping effect>acidic dissolution effect>CA enzymatic effect. The results of the second experiment demonstrated further that the limestone dissolution effect of the acidic materials excreted by fungi was stronger than that of CA excreted by fungi. Nevertheless, CA still played an important role in promoting the dissolution of limestone.

  20. Prediction of acid hydrolysis of lignocellulosic materials in batch and plug flow reactors.

    PubMed

    Jaramillo, Oscar Johnny; Gómez-García, Miguel Ángel; Fontalvo, Javier

    2013-08-01

    This study unifies contradictory conclusions reported in literature on acid hydrolysis of lignocellulosic materials, using batch and plug flow reactors, regarding the influence of the initial liquid ratio of acid aqueous solution to solid lignocellulosic material on sugar yield and concentration. The proposed model takes into account the volume change of the reaction media during the hydrolysis process. An error lower than 8% was found between predictions, using a single set of kinetic parameters for several liquid to solid ratios, and reported experimental data for batch and plug flow reactors. For low liquid-solid ratios, the poor wetting and the acid neutralization, due to the ash presented in the solid, will both reduce the sugar yield. Also, this study shows that both reactors are basically equivalent in terms of the influence of the liquid to solid ratio on xylose and glucose yield.

  1. Investigations of surface acidities and pore size distributions of selected pillared layered materials

    SciTech Connect

    Odom, M.A.; Wade, K.L.; Morgan, D.M.; White, J.L.; Schroeder, N.C.

    1996-10-01

    Pillared Layered Materials (PLMs) are being designed for a variety of applications. Currently, PLMs are being prepared in this laboratory for the selective sorption of radionuclides from liquid-nuclear wastes. It is important to have a good understanding of characteristics, such as pore size distributions and surface acidities, in order to tailor there sizes and environments are manipulated by varying the layered materials and pillaring species used for preparing the PLM. A variety of techniques have been employed to study these characteristics. For this study the pore size distributions were derived by determining the sorption of hydrocarbons of various sizes and shapes into the PLMs. The surface acidities were probed by sorbing basic species, such as ammonia and pyridine, and assessing the interactions with the acid sites using FTIR spectroscopy.

  2. Biomolecular interactions of emerging two-dimensional materials with aromatic amino acids

    NASA Astrophysics Data System (ADS)

    Mallineni, Sai Sunil Kumar; Karakaya, Mehmet; Podila, Ramakrishna; Rao, Apparao

    The present work experimentally investigates the interaction of aromatic amino acids, viz., tyrosine, tryptophan, and phenylalanine with novel two-dimensional (2D) materials including graphene (G), graphene oxide (GO), and boron nitride (BN). Photoluminescence, micro-Raman spectroscopy and cyclic voltammetry were employed to investigate the nature of interactions and possible charge transfer between 2D materials and amino acids. Consistent with previous theoretical studies, graphene and BN were observed to interact with amino acids through π- π interactions. Furthermore, we found that GO exhibits strong interactions with tryptophan and tyrosine as compared to graphene and BN, which we attribute to the formation of H-bonds between tryptophan and GO as shown theoretically in Ref. 2. On the other hand, phenylalanine did not exhibit much difference in interactions with G, GO, and BN. Clemson Nanomaterials Center, Clemson University, Clemson, SC, USA.

  3. In-depth compositional analysis of water-soluble and -insoluble organic substances in fine (PM2.5) airborne particles using ultra-high-resolution 15T FT-ICR MS and GC×GC-TOFMS.

    PubMed

    Choi, Jung Hoon; Ryu, Jijeong; Jeon, Sodam; Seo, Jungju; Yang, Yung-Hun; Pack, Seung Pil; Choung, Sungwook; Jang, Kyoung-Soon

    2017-03-05

    Airborne particulate matter consisting of ionic species, salts, heavy metals and carbonaceous material is one of the most serious environmental pollutants owing to its impacts on the environment and human health. Although elemental and organic carbon compounds are known to be major components of aerosols, information on the elemental composition of particulate matter remains limited because of the broad range of compounds involved and the limits of analytical instruments. In this study, we investigated water-soluble and -insoluble organic compounds in fine (PM2.5) airborne particles collected during winter in Korea to better understand the elemental compositions and distributions of these compounds. To collect ultra-high-resolution mass profiles, we analyzed water-soluble and -insoluble organic compounds, extracted with water and dichloromethane, respectively, using an ultra-high-resolution 15 T Fourier transform ion cyclotron resonance (15T FT-ICR) mass spectrometer in positive ion mode (via both electrospray ionization [ESI] and atmospheric pressure photoionization [APPI] for water-extracts and via APPI for dichloromethane-extracts). In conjunction with the FT-ICR mass spectrometry (MS) data, subsequent two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS) data were used to identify potentially hazardous organic components, such as polycyclic aromatic hydrocarbons. This analysis provided information on the sources of ambient particles collected during winter season and partial evidence of contributions to the acidity of organic content in PM2.5 particles. The compositional and structural features of water-soluble and -insoluble organic compounds from PM2.5 particles are important for understanding the potential impacts of aerosol-carried organic substances on human health and global ecosystems in future toxicological studies.

  4. Sucrose phosphate synthase activity and the co-ordination of carbon partitioning during sucrose and amino acid accumulation in desiccation-tolerant leaf material of the C4 resurrection plant Sporobolus stapfianus during dehydration.

    PubMed

    Whittaker, Anne; Martinelli, Tommaso; Farrant, Jill M; Bochicchio, Adriana; Vazzana, Concetta

    2007-01-01

    Both sucrose and amino acids accumulate in desiccation-tolerant leaf material of the C(4) resurrection plant, Sporobolus stapfianus Gandoger (Poaceae). The present investigation was aimed at examining sucrose phosphate synthase (SPS) activity and various metabolic checkpoints involved in the co-ordination of carbon partitioning between these competing pathways during dehydration. In the initial phase of dehydration, photosynthesis and starch content declined to immeasurable levels, whilst significant increases in hexose sugars, sucrose, and amino acids were associated with concomitant significant increases in SPS and pyruvate kinase (PK) activities, and maximal activity levels of phosphoenolpyruvate carboxylase (PEPCase), NADP-dependent isocitrate dehydrogenase (NADP-ICDH), and NADH-dependent glutamate synthase (NADH-GOGAT). The next phase of dehydration was characterized by changes in metabolism coinciding with net hexose sugar phosphorylation. This phase was characterized by a further significant increase in sucrose accumulation, with increased rates of net sucrose accumulation and maximum rates of SPS activity measured under both saturating and limiting (inhibitory) conditions. SPS protein was also increased. The stronger competitive edge of SPS for carbon entering glycolysis during hexose phosphorylation was also demonstrated by the further decrease in respiration and the simultaneous, significant decline in both PEPCase and PK activities. A decreased anabolic demand for 2-oxoglutarate (2OG), which remained constant, was shown by the co-ordinated decrease in GOGAT. It is proposed that the further increase in amino acids in this phase of dehydration may be in part attributable to the breakdown of insoluble proteins.

  5. Optical properties of selected components of mineral dust aerosol processed with organic acids and humic material

    NASA Astrophysics Data System (ADS)

    Alexander, Jennifer M.; Grassian, V. H.; Young, M. A.; Kleiber, P. D.

    2015-03-01

    Visible light scattering phase function and linear polarization profiles of mineral dust components processed with organic acids and humic material are measured, and results are compared to T-matrix simulations of the scattering properties. Processed samples include quartz mixed with humic material, and calcite reacted with acetic and oxalic acids. Clear differences in light scattering properties are observed for all three processed samples when compared to the unprocessed dust or organic salt products. Results for quartz processed with humic acid sodium salt (NaHA) indicate the presence of both internally mixed quartz-NaHA particles and externally mixed NaHA aerosol. Simulations of light scattering suggest that the processed quartz particles become more moderate in shape due to the formation of a coating of humic material over the mineral core. Experimental results for calcite reacted with acetic acid are consistent with an external mixture of calcite and the reaction product, calcium acetate. Modeling of the light scattering properties does not require any significant change to the calcite particle shape distribution although morphology changes cannot be ruled out by our data. It is expected that calcite reacted with oxalic acid will produce internally mixed particles of calcite and calcium oxalate due to the low solubility of the product salt. However, simulations of the scattering for the calcite-oxalic acid system result in rather poor fits to the data when compared to the other samples. The poor fit provides a less accurate picture of the impact of processing in the calcite-oxalic acid system.

  6. Nucleic acids and smart materials: advanced building blocks for logic systems.

    PubMed

    Pu, Fang; Ren, Jinsong; Qu, Xiaogang

    2014-09-03

    Logic gates can convert input signals into a defined output signal, which is the fundamental basis of computing. Inspired by molecular switching from one state to another under an external stimulus, molecular logic gates are explored extensively and recognized as an alternative to traditional silicon-based computing. Among various building blocks of molecular logic gates, nucleic acid attracts special attention owing to its specific recognition abilities and structural features. Functional materials with unique physical and chemical properties offer significant advantages and are used in many fields. The integration of nucleic acids and functional materials is expected to bring about several new phenomena. In this Progress Report, recent progress in the construction of logic gates by combining the properties of a range of smart materials with nucleic acids is introduced. According to the structural characteristics and composition, functional materials are categorized into three classes: polymers, noble-metal nanomaterials, and inorganic nanomaterials. Furthermore, the unsolved problems and future challenges in the construction of logic gates are discussed. It is hoped that broader interests in introducing new smart materials into the field are inspired and tangible applications for these constructs are found.

  7. Composites of manganese oxide with carbon materials as catalysts for the ozonation of oxalic acid.

    PubMed

    Orge, C A; Órfão, J J M; Pereira, M F R

    2012-04-30

    Manganese oxide and manganese oxide-carbon composites were prepared and tested as catalysts for the removal of oxalic acid by ozonation. Their performances were compared with the parent carbon material (activated carbon or carbon xerogel) used to prepare the composites. Oxalic acid degradation by carbon materials is slower than that attained with manganese oxide or manganese oxide-carbon composites. A complete degradation after 90 and 45 min of reaction was obtained for carbon materials and for the catalysts containing manganese, respectively. The ozonation in the presence of the prepared composites are supposed to occur mainly by surface reactions, following a direct oxidation mechanism by molecular ozone and/or surface oxygenated radicals.

  8. Reflectance and Emittance Properties of Spring-formed Ferricretes and Acid Mine Drainage Materials: Relevance to Remote Sensing of Mars

    NASA Astrophysics Data System (ADS)

    Farrand, W. H.; Lane, M. D.

    1999-03-01

    The reflectance and emittance properties of minerals associated with spring formed ferricretes and acid mine drainage materials is described. It is suggested that they may be appropriate analog materials for certain regions on Mars.

  9. A modified enzyme-linked immunosorbent assay adapted for immunodetection of low amounts of water-insoluble proteins.

    PubMed

    Godfrin, Dominique; Sénéchal, Hélène; Sutra, Jean-Pierre; Busnel, Jean-Marc; Desvaux, François-Xavier; Peltre, Gabriel

    2007-09-30

    A mixture of thiourea, urea and CHAPS (TUC) is an excellent solvent compatible with isoelectrofocusing (IEF) separation of water-insoluble protein extracts, and their subsequent two-dimensional gel electrophoresis is an important step in proteomic studies. The main aim of this work was to quantify extremely low amounts of water-insoluble proteins contained, for instance, in samples collected in bio-aerosol samplers. High CHAPS concentrations solubilize many proteins. However, enzyme-linked immunosorbent assay (ELISA), which is the most popular immunodetection method of quantifying antigens, is unfortunately not compatible with these high CHAPS concentrations and with the low protein concentrations of TUC extracts. The most common mixture used to solubilize these proteins contains 2 mol l(-1) thiourea, 7 mol l(-1) urea and 5% w/v CHAPS. This paper shows that these components inhibit the adsorption and/or recognition of proteins on microtitration plates, preventing antigen quantification under classic ELISA conditions. We have tried several solvents (ethanol, isopropanol, acetonitrile and trichloroacetic acid) to make the TUC-soluble proteins stick to the ELISA plates, and ethanol was shown to be the most appropriate. In this study, we have defined a new ELISA protocol allowing rapid and sensitive detection of low concentrations (60-500 ng ml(-1)) of water-insoluble proteins extracted with high concentrations of TUC.

  10. Synthesis of acid-base bifunctional mesoporous materials by oxidation and thermolysis

    SciTech Connect

    Yu, Xiaofang; Zou, Yongcun; Wu, Shujie; Liu, Heng; Guan, Jingqi; Kan, Qiubin

    2011-06-15

    Graphical abstract: A novel and efficient method has been developed for the synthesis of acid-base bifunctional catalyst. The obtained sample of SO{sub 3}H-MCM-41-NH{sub 2} containing amine and sulfonic acids exhibits excellent catalytic activity in aldol condensation reaction. Research highlights: {yields} Synthesize acid-base bifunctional mesoporous materials SO{sub 3}H-MCM-41-NH{sub 2}. {yields} Oxidation and then thermolysis to generate acidic site and basic site. {yields} Exhibit good catalytic performance in aldol condensation reaction between acetone and various aldehydes. -- Abstract: A novel and efficient method has been developed for the synthesis of acid-base bifunctional catalyst SO{sub 3}H-MCM-41-NH{sub 2}. This method was achieved by co-condensation of tetraethylorthosilicate (TEOS), 3-mercaptopropyltrimethoxysilane (MPTMS) and (3-triethoxysilylpropyl) carbamicacid-1-methylcyclohexylester (3TAME) in the presence of cetyltrimethylammonium bromide (CTAB), followed by oxidation and then thermolysis to generate acidic site and basic site. X-ray diffraction (XRD) and transmission electron micrographs (TEM) show that the resultant materials keep mesoporous structure. Thermogravimetric analysis (TGA), X-ray photoelectron spectra (XPS), back titration, solid-state {sup 13}C CP/MAS NMR and solid-state {sup 29}Si MAS NMR confirm that the organosiloxanes were condensed as a part of the silica framework. The bifunctional sample (SO{sub 3}H-MCM-41-NH{sub 2}) containing amine and sulfonic acids exhibits excellent acid-basic properties, which make it possess high activity in aldol condensation reaction between acetone and various aldehydes.

  11. Evaluation of the acid properties of porous zirconium-doped and undoped silica materials

    SciTech Connect

    Fuentes-Perujo, D.; Santamaria-Gonzalez, J.; Merida-Robles, J.; Rodriguez-Castellon, E.; Jimenez-Lopez, A.; Maireles-Torres, P. . E-mail: maireles@uma.es; Moreno-Tost, R.

    2006-07-15

    A series of porous silica and Zr-doped silica molecular sieves, belonging to the MCM-41 and MSU families, were prepared and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and N{sub 2} adsorption at 77 K. Their acid properties have been evaluated by NH{sub 3}-TPD, adsorption of pyridine and deuterated acetonitrile coupled to FT-IR spectroscopy and the catalytic tests of isopropanol decomposition and isomerization of 1-butene. The acidity of purely siliceous solids were, in all cases, very low, while the incorporation of Zr(IV) into the siliceous framework produced an enhancement of the acidity. The adsorption of basic probe molecules and the catalytic behaviour revealed that Zr-doped MSU-type silica was more acidic than the analogous Zr-MCM-41 solid, with a similar Zr content. This high acidity observed in the case of Zr-doped silica samples is due to the presence of surface zirconium atoms with a low coordination, mainly creating Lewis acid sites. - Graphical abstract: The adsorption of basic probe molecules and the catalytic behaviour have revealed that MSU-type materials are more acidic than the analogous MCM-41 solids, mainly after the incorporation of zirconium into the silica framework.

  12. Vinasse organic matter quality and mineralization potential, as influenced by raw material, fermentation and concentration processes.

    PubMed

    Parnaudeau, V; Condom, N; Oliver, R; Cazevieille, P; Recous, S

    2008-04-01

    Both dilute and concentrated vinasse can be spread on agricultural fields or used as organic fertilizer. The effects of different characteristics of the original raw material on the biochemical composition of vinasse and their C and N mineralization in soil were investigated. Vinasse samples were obtained from similar industrial fermentation processes based on the growth of microorganisms on molasses from different raw material (sugar beet or sugar cane) and vinasse concentration (dilute or concentrated). The nature of the raw material used for fermentation had the greatest effect on the nature and size of the resistant organic pool. This fraction included aromatic compounds originating from the raw material or from complex molecules and seemed to be quantitatively related to acid-insoluble N. Samples derived from sugar beet were richer in N compounds and induced greater net N mineralization. The effect of evaporation varied with the nature of the raw material. Concentration led to a slight increase in the abundance of phenolic compounds, acid-insoluble fraction, and a slight decrease in the labile fraction of vinasses partly or totally derived from sugar beet. The effect of the dilute vinasse from sugar cane was greater. The concentrated vinasse had a smaller labile fraction, induced N immobilization at the beginning of incubation, and exhibited greater N concentration in the acid-insoluble fraction than the dilute vinasse.

  13. Nanocrosses of lead sulphate as the negative active material of lead acid batteries

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Gao, Pengran; Bu, Xianfu; Kuang, Guizhi; Liu, Wei; Lei, Lixu

    2014-10-01

    Lead sulphate transforms into PbO2 and Pb in the positive and negative electrodes, respectively, when a lead acid battery is charged, thus, it is an active material. It is also generally acknowledged that sulphation results in the failure of lead acid batteries; therefore, it is very interesting to find out how to make lead sulphate more electrochemically active. Here, we demonstrate that nanocrystalline lead sulphate can be used as excellent negative active material in lead acid batteries. The lead sulphate nanocrystals, which are prepared by a facile chemical precipitation of aqueous lead acetate and sodium sulphate in a few minutes, look like crosses with diameter of each arm being 100 nm to 3 μm. The electrode is effectively formed in much shorter time than traditional technique, yet it discharges a capacity of 103 mA h g-1 at the current density of 120 mA g-1, which is 24% higher than that discharged by the electrode made from leady oxide under the same condition. During 100% DOD cycles, more than 80% of that capacity remains in 550 cycles. These results show that lead sulphate can be a nice negative active material in lead acid batteries.

  14. Quality improvement of acidic soils by biochar derived from renewable materials.

    PubMed

    Moon, Deok Hyun; Hwang, Inseong; Chang, Yoon-Young; Koutsospyros, Agamemnon; Cheong, Kyung Hoon; Ji, Won Hyun; Park, Jeong-Hun

    2017-02-01

    Biochar derived from waste plant materials and agricultural residues was used to improve the quality of an acidic soil. The acidic soil was treated for 1 month with both soy bean stover-derived biochar and oak-derived biochar in the range of 1 to 5 wt% for pH improvement and exchangeable cation enhancement. Following 1 month of treatment, the soil pH was monitored and exchangeable cations were measured. Moreover, a maize growth experiment was performed for 14 days with selected treated soil samples to confirm the effectiveness of the treatment. The results showed that the pH of the treated acidic soil increased by more than 2 units, and the exchangeable cation values were greatly enhanced upon treatment with 5 wt% of both biochars, after 1 month of curing. Maize growth was superior in the 3 wt% biochar-treated samples compared to the control sample. The presented results demonstrate the effective use of biochar derived from renewable materials such as waste plant materials and agricultural residues for quality improvement of acidic soils.

  15. Morphological Study of Insoluble Organic Matter Residues from Primitive

    NASA Technical Reports Server (NTRS)

    Changela, H. G.; Stroud, R. M.; Peeters, Z.; Nittler, L. R.; Alexander, C. M. O'D.; DeGregorio, B. T.; Cody, G. D.

    2012-01-01

    Insoluble organic matter (IOM) constitutes a major proportion, 70-99%, of the total organic carbon found in primitive chondrites [1, 2]. One characteristic morphological component of IOM is nanoglobules [3, 4]. Some nanoglobules exhibit large N-15 and D enrichments relative to solar values, indicating that they likely originated in the ISM or the outskirts of the protoplanetary disk [3]. A recent study of samples from the Tagish Lake meteorite with varying levels of hydrothermal alteration suggest that nanoglobule abundance decreases with increasing hydrothermal alteration [5]. The aim of this study is to further document the morphologies of IOM from a range of primitive chondrites in order to determine any correlation of morphology with petrographic grade and chondrite class that could constrain the formation and/or alteration mechanisms.

  16. Iron promotes protein insolubility and aging in C. elegans

    PubMed Central

    Klang, Ida M.; Schilling, Birgit; Sorensen, Dylan J.; Sahu, Alexandria K.; Kapahi, Pankaj; Andersen, Julie K.; Swoboda, Peter; Killilea, David W.; Gibson, Bradford W.; Lithgow, Gordon J.

    2014-01-01

    Many late-onset proteotoxic diseases are accompanied by a disruption in homeostasis of metals (metallostasis) including iron, copper and zinc. Although aging is the most prominent risk factor for these disorders, the impact of aging on metallostasis and its role in proteotoxic disease remain poorly understood. Moreover, it is not clear whether a loss of metallostasis influences normal aging. We have investigated the role of metallostasis in longevity of Caenorhabditis elegans. We found that calcium, copper, iron, and manganese levels increase as a function of age, while potassium and phosphorus levels tend to decrease. Increased dietary iron significantly accelerated the age-related accumulation of insoluble protein, a molecular pathology of aging. Proteomic analysis revealed widespread effects of dietary iron in multiple organelles and tissues. Pharmacological interventions to block accumulation of specific metals attenuated many models of proteotoxicity and extended normal lifespan. Collectively, these results suggest that a loss of metallostasis with aging contributes to age-related protein aggregation. PMID:25554795

  17. CLAY MINERALOGY OF INSOLUBLE RESIDUES IN MARINE EVAPORITES.

    USGS Publications Warehouse

    Bodine, Marc W.

    1985-01-01

    Insoluble residues from three sequences of Paleozoic marine evaporites (Retsof salt bed in western New York, Salado Formation in south-eastern New Mexico, and Paradox Member of the Hermosa Formation in southeastern Utah) are rich in trioctahedral clays. Chlorite (clinochlore), corrensite (mixed-layer chlorite-trioctahedral smectite), talc, and illite (the only dioctahedral clay) are the dominant clay minerals; serpentine, discrete trioctahedral smectite (saponite), and interstratified talc-trioctahedral smectite are sporadically abundant. These clay-mineral assemblages differ chemically and mineralogically from those observed in most continental and normal marine rocks, which commonly contain kaolinite, dioctahedral smectite (beidellite-montmorillonite), illite, mixed-layer illite-dioctahedral smectite, and, in most cases, no more than minor quantities of trioctahedral clay minerals. The distinctive clay mineralogy in these evaporite sequences suggests a largely authigenic origin. These clay minerals are thought to have formed during deposition and early diagenesis through interaction between argillaceous detritus and Mg-rich marine evaporite brines.

  18. Study of a nickel-copper filter for the future conditioning of insoluble residues

    NASA Astrophysics Data System (ADS)

    Massoni, Nicolas

    2016-10-01

    This paper deals with the feasibility of a separate conditioning for insoluble residues coming from spent nuclear fuel reprocessing. The two possible conditioning routes considered for insoluble residues were (i) added with cladding hulls with the considered filter (route #1) or (ii) melted with a nickel copper alloy already studied (route #2). Only route #2 was dealt with in this study. In France, the current practice is to store insoluble residues in a water suspension. For the two conditioning routes described here, dry insoluble residues are required for safety with melted metals. A nickel-copper filter was developed that can serve for the two types of conditioning. A filtration test performed with molybdenum particles as insoluble residue surrogates was done. The particle-charged filter was sintered, and Mo particles were kept inside the filter. Thus an integrated flowsheet for the filtration and immobilization of insoluble residues was demonstrated.

  19. Fermentative production of lactic acid from renewable materials: recent achievements, prospects, and limits.

    PubMed

    Wang, Ying; Tashiro, Yukihiro; Sonomoto, Kenji

    2015-01-01

    The development and implementation of renewable materials for the production of versatile chemical resources have gained considerable attention recently, as this offers an alternative to the environmental problems caused by the petroleum industry and the limited supply of fossil resources. Therefore, the concept of utilizing biomass or wastes from agricultural and industrial residues to produce useful chemical products has been widely accepted. Lactic acid plays an important role due to its versatile application in the food, medical, and cosmetics industries and as a potential raw material for the manufacture of biodegradable plastics. Currently, the fermentative production of optically pure lactic acid has increased because of the prospects of environmental friendliness and cost-effectiveness. In order to produce lactic acid with high yield and optical purity, many studies focus on wild microorganisms and metabolically engineered strains. This article reviews the most recent advances in the biotechnological production of lactic acid mainly by lactic acid bacteria, and discusses the feasibility and potential of various processes.

  20. 31P NMR characterization and efficiency of new types of water-insoluble phosphate fertilizers to supply plant-available phosphorus in diverse soil types.

    PubMed

    Erro, Javier; Baigorri, Roberto; Yvin, Jean-Claude; Garcia-Mina, Jose M

    2011-03-09

    Hydroponic plant experiments demonstrated the efficiency of a type of humic acid-based water-insoluble phosphate fertilizers, named rhizosphere controlled fertilizers (RCF), to supply available phosphorus (P) to different plant species. This effect was well correlated to the root release of specific organic acids. In this context, the aims of this study are (i) to study the chemical nature of RCF using solid-state (31)P NMR and (ii) to evaluate the real efficiency of RCF matrix as a source of P for wheat plants cultivated in an alkaline and acid soil in comparison with traditional water-soluble (simple superphosphate, SSP) and water-insoluble (dicalcium phosphate, DCP) P fertilizers. The (31)P NMR study revealed the formation of multimetal (double and triple, MgZn and/or MgZnCa) phosphates associated with chelating groups of the humic acid through the formation of metal bridges. With regard to P fertilizer efficiency, the results obtained show that the RCF matrix produced higher plant yields than SSP in both types of soil, with DCP and the water-insoluble fraction from the RCF matrix (WI) exhibiting the best results in the alkaline soil. By contrast, in the acid soil, DCP showed very low efficiency, WI performed on a par with SSP, and RCF exhibited the highest efficiency, thus suggesting a protector effect of humic acid from soil fixation.

  1. Insoluble coatings for Stirling engine heat pipe condenser surfaces. Final report

    SciTech Connect

    Dussinger, P.M.

    1993-09-01

    The work done by Thermacore, Inc., Lancaster, Pennsylvania, for the Phase 1, 1992 SBIR National Aeronautics and Space Administration Contract, Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces' is described. The work was performed between January 1992 and July 1992. Stirling heat engines are being developed for electrical power generation use on manned and unmanned earth orbital and planetary missions. Dish Stirling solar systems and nuclear reactor Stirling systems are two of the most promising applications of the Stirling engine electrical power generation technology. The sources of thermal energy used to drive the Stirling engine typically are non-uniform in temperature and heat flux. Liquid metal heat pipe receivers are used as thermal transformers and isothermalizers to deliver the thermal energy at a uniform high temperature to the heat input section of the Stirling engine. The use of a heat pipe receiver greatly enhances system efficiency and potential life span. One issue that is raised during the design phase of heat pipe receivers is the potential solubility corrosion of the Stirling engine heat input section by the liquid metal working fluid. This Phase 1 effort initiated a program to evaluate and demonstrate coatings, applied to nickel based Stirling engine heater head materials, that are practically 'insoluble' in sodium, potassium, and NaK. This program initiated a study of nickel aluminide as a coating and developed and demonstrated a heat pipe test vehicle that can be used to test candidate materials and coatings. Nickel 200 and nickel aluminide coated Nickel 200 were tested for 1000 hours at 800 C at a condensation heat flux of 25 W/sq cm. Subsequent analyses of the samples showed no visible sign of solubility corrosion of either coated or uncoated samples. The analysis technique, photomicrographs at 200X, has a resolution of better than 2.5 microns (.0001 in).

  2. Pretreatment of solid carbonaceous material with dicarboxylic aromatic acids to prevent scale formation

    SciTech Connect

    Brunson, R.J.

    1982-06-01

    Scale formation during the liquefaction of lower ranking coals and similar carbonaceous materials is significantly reduced and/or prevented by pretreatment with a pretreating agent selected from the group consisting of phthalic acid, phthalic anhydride, pyromellitic acid and pyromellitic anhydride. The pretreatment is believed to convert the scale-forming components to the corresponding phthalate and/or pyromellitate prior to liquefaction. The pretreatment is accomplished at a total pressure within the range from about 1 to about 2 atmospheres. Temperature during pretreatment will generally be within the range from about 5 to about 80/sup 0/ C.

  3. Pretreatment of solid carbonaceous material with dicarboxylic aromatic acids to prevent scale formation

    SciTech Connect

    Brunson, Roy J.

    1982-01-01

    Scale formation during the liquefaction of lower ranking coals and similar carbonaceous materials is significantly reduced and/or prevented by pretreatment with a pretreating agent selected from the group consisting of phthalic acid, phthalic anhydride, pyromellitic acid and pyromellitic anhydride. The pretreatment is believed to convert the scale-forming components to the corresponding phthalate and/or pyromellitate prior to liquefaction. The pretreatment is accomplished at a total pressure within the range from about 1 to about 2 atmospheres. Temperature during pretreatment will generally be within the range from about 5.degree. to about 80.degree. C.

  4. Tank 12H Acidic Chemical Cleaning Sample Analysis And Material Balance

    SciTech Connect

    Martino, C. J.; Reboul, S. H.; Wiersma, B. J.; Coleman, C. J.

    2013-11-08

    A process of Bulk Oxalic Acid (BOA) chemical cleaning was performed for Tank 12H during June and July of 2013 to remove all or a portion of the approximately 4400 gallon sludge heel. Three strikes of oxalic acid (nominally 4 wt% or 2 wt%) were used at 55°C and tank volumes of 96- to 140-thousand gallons. This report details the sample analysis of a scrape sample taken prior to BOA cleaning and dip samples taken during BOA cleaning. It also documents a rudimentary material balance for the Tank 12H cleaning results.

  5. Characterization and Localization of Insoluble Organic Matrices Associated with Diatom Cell Walls: Insight into Their Roles during Cell Wall Formation

    PubMed Central

    Tesson, Benoit; Hildebrand, Mark

    2013-01-01

    Organic components associated with diatom cell wall silica are important for the formation, integrity, and function of the cell wall. Polysaccharides are associated with the silica, however their localization, structure, and function remain poorly understood. We used imaging and biochemical approaches to describe in detail characteristics of insoluble organic components associated with the cell wall in 5 different diatom species. Results show that an insoluble organic matrix enriched in mannose, likely the diatotepum, is localized on the proximal surface of the silica cell wall. We did not identify any organic matrix embedded within the silica. We also identified a distinct material consisting of glucose polymer with variable localization depending on the species. In some species this component was directly involved in the morphogenesis of silica structure while in others it appeared to be only a structural component of the cell wall. A novel glucose-rich structure located between daughter cells during division was also identified. This work for the first time correlates the structure, composition, and localization of insoluble organic matrices associated with diatom cell walls. Additionally we identified a novel glucose polymer and characterized its role during silica structure formation. PMID:23626714

  6. Crosslinked hydrogels—a promising class of insoluble solid molecular dispersion carriers for enhancing the delivery of poorly soluble drugs

    PubMed Central

    Sun, Dajun D.; Lee, Ping I.

    2014-01-01

    Water-insoluble materials containing amorphous solid dispersions (ASD) are an emerging category of drug carriers which can effectively improve dissolution kinetics and kinetic solubility of poorly soluble drugs. ASDs based on water-insoluble crosslinked hydrogels have unique features in contrast to those based on conventional water-soluble and water-insoluble carriers. For example, solid molecular dispersions of poorly soluble drugs in poly(2-hydroxyethyl methacrylate) (PHEMA) can maintain a high level of supersaturation over a prolonged period of time via a feedback-controlled diffusion mechanism thus avoiding the initial surge of supersaturation followed by a sharp decline in drug concentration typically encountered with ASDs based on water-soluble polymers. The creation of both immediate- and controlled-release ASD dosage forms is also achievable with the PHEMA based hydrogels. So far, ASD systems based on glassy PHEMA have been shown to be very effective in retarding precipitation of amorphous drugs in the solid state to achieve a robust physical stability. This review summarizes recent research efforts in investigating the potential of developing crosslinked PHEMA hydrogels as a promising alternative to conventional water-soluble ASD carriers, and a related finding that the rate of supersaturation generation does affect the kinetic solubility profiles implications to hydrogel based ASDs. PMID:26579361

  7. Preparation, characterization, and thermal properties of starch microencapsulated fatty acids as phase change materials thermal energy storage applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stable starch-oil composites can be prepared from renewable resources by excess steam jet-cooking aqueous slurries of starch and vegetable oils or other hydrophobic materials. Fatty acids such as stearic acid are promising phase change materials (PCMs) for latent heat thermal energy storage applica...

  8. Use of Fly Ash as a Liming Material for Corn and Soybean Production on an Acidic Sandy Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fly ash (FA) produced from subbituminous coal combustion can potentially serve as a lime material for crop production in acidic soils in areas. A five-year study was conducted to determine if FA can be used as a liming material in an acid sandy soil under corn and soybean grain production. Fly ash...

  9. Hydrogels from Amorphous Calcium Carbonate and Polyacrylic Acid: Bio-Inspired Materials for "Mineral Plastics".

    PubMed

    Sun, Shengtong; Mao, Li-Bo; Lei, Zhouyue; Yu, Shu-Hong; Cölfen, Helmut

    2016-09-19

    Given increasing environmental issues due to the large usage of non-biodegradable plastics based on petroleum, new plastic materials, which are economic, environmentally friendly, and recyclable are in high demand. One feasible strategy is the bio-inspired synthesis of mineral-based hybrid materials. Herein we report a facile route for an amorphous CaCO3 (ACC)-based hydrogel consisting of very small ACC nanoparticles physically cross-linked by poly(acrylic acid). The hydrogel is shapeable, stretchable, and self-healable. Upon drying, the hydrogel forms free-standing, rigid, and transparent objects with remarkable mechanical performance. By swelling in water, the material can completely recover the initial hydrogel state. As a matrix, thermochromism can also be easily introduced. The present hybrid hydrogel may represent a new class of plastic materials, the "mineral plastics".

  10. Chemical modeling of acid-base properties of soluble biopolymers derived from municipal waste treatment materials.

    PubMed

    Tabasso, Silvia; Berto, Silvia; Rosato, Roberta; Marinos, Janeth Alicia Tafur; Ginepro, Marco; Zelano, Vincenzo; Daniele, Pier Giuseppe; Montoneri, Enzo

    2015-02-04

    This work reports a study of the proton-binding capacity of biopolymers obtained from different materials supplied by a municipal biowaste treatment plant located in Northern Italy. One material was the anaerobic fermentation digestate of the urban wastes organic humid fraction. The others were the compost of home and public gardening residues and the compost of the mix of the above residues, digestate and sewage sludge. These materials were hydrolyzed under alkaline conditions to yield the biopolymers by saponification. The biopolymers were characterized by 13C NMR spectroscopy, elemental analysis and potentiometric titration. The titration data were elaborated to attain chemical models for interpretation of the proton-binding capacity of the biopolymers obtaining the acidic sites concentrations and their protonation constants. The results obtained with the models and by NMR spectroscopy were elaborated together in order to better characterize the nature of the macromolecules. The chemical nature of the biopolymers was found dependent upon the nature of the sourcing materials.

  11. Rates of dissolution and biodegradation of water-insoluble organic compounds.

    PubMed Central

    Thomas, J M; Yordy, J R; Amador, J A; Alexander, M

    1986-01-01

    We conducted a study of the relationship between the dissolution rates of organic compounds that are sparingly soluble in water and the biodegradation of these compounds by mixed cultures of bacteria. The rates of dissolution of naphthalene and 4-chlorobiphenyl were directly related to their surface areas. The bacteria caused a decline in the concentration of the soluble substrate. The rate of bacterial growth fell abruptly when 4-chlorobiphenyl or naphthalene was no longer detectable in solution. The population continued to increase in media with different surface areas of insoluble 4-chlorobiphenyl, but the final counts were higher in media in which the surface areas of the substrate were larger. The rates of dissolution of palmitic acid, octadecane, di(2-ethylhexyl) phthalate, and 1-naphthyl N-methylcarbamate were determined in the absence of microorganisms. A mixed culture of microorganisms mineralized palmitic acid, di(2-ethylhexyl) phthalate, and Sevin (1-naphthyl N-methylcarbamate) at a logarithmic rate, but octadecane mineralization was linear. The rates of mineralization at the end of the active phase of the biodegradation were lower than the rate of dissolution of palmitic acid but higher than the rate of dissolution of octadecane in the uninoculated medium. We suggest that spontaneous dissolution rates are only one of the factors that govern the rates of biodegradation. PMID:3092736

  12. Direct Image-Based Enumeration of Clostridium phytofermentans Cells on Insoluble Plant Biomass Growth Substrates

    PubMed Central

    Alvelo-Maurosa, Jesús G.; Lee, Scott J.; Hazen, Samuel P.

    2015-01-01

    A dual-fluorescent-dye protocol to visualize and quantify Clostridium phytofermentans ISDg (ATCC 700394) cells growing on insoluble cellulosic substrates was developed by combining calcofluor white staining of the growth substrate with cell staining using the nucleic acid dye Syto 9. Cell growth, cell substrate attachment, and fermentation product formation were investigated in cultures containing either Whatman no. 1 filter paper, wild-type Sorghum bicolor, or a reduced-lignin S. bicolor double mutant (bmr-6 bmr-12 double mutant) as the growth substrate. After 3 days of growth, cell numbers in cultures grown on filter paper as the substrate were 6.0- and 2.2-fold higher than cell numbers in cultures with wild-type sorghum and double mutant sorghum, respectively. However, cells produced more ethanol per cell when grown with either sorghum substrate than with filter paper as the substrate. Ethanol yields of cultures were significantly higher with double mutant sorghum than with wild-type sorghum or filter paper as the substrate. Moreover, ethanol production correlated with cell attachment in sorghum cultures: 90% of cells were directly attached to the double mutant sorghum substrate, while only 76% of cells were attached to wild-type sorghum substrate. With filter paper as the growth substrate, ethanol production was correlated with cell number; however, with either wild-type or mutant sorghum, ethanol production did not correlate with cell number, suggesting that only a portion of the microbial cell population was active during growth on sorghum. The dual-staining procedure described here may be used to visualize and enumerate cells directly on insoluble cellulosic substrates, enabling in-depth studies of interactions of microbes with plant biomass. PMID:26637592

  13. Organic/inorganic hybrid amine and sulfonic acid tethered silica materials: Synthesis, characterization and application

    NASA Astrophysics Data System (ADS)

    Hicks, Jason Christopher

    The major goals of this thesis were to: (1) create a site-isolated aminosilica material with higher amine loadings than previously reported isolation methods, (2) use spectroscopic, reactivity, and catalytic (olefin polymerization precatalysts) probes to determine isolation of amine groups on these organic/inorganic hybrid materials, (3) synthesize an organic/inorganic hybrid material capable of activating Group 4 olefin polymerization precatalysts, and (4) synthesize a high amine loaded organic/inorganic hybrid material capable of reversibly capturing CO2 in a simulated flue gas stream. The underlying motivation of this research involved the synthesis and design of novel amine and sulfonic acid materials. Traditional routes to synthesize aminosilicas have led to the formation of a high loading of multiple types of amine sites on the silica surface. Part of this research involved the creation of a new aminosilica material via a protection/deprotection method designed to prevent multiple sites, while maintaining a relatively high loading. As a characterization technique, fluorescence spectroscopy of pyrene-based fluorophores loaded on traditional aminosilicas and site-isolated aminosilicas was used to probe the degree of site-isolation obtained with these methods. Also, this protection/deprotection method was compared to other reported isolation techniques with heterogeneous Group 4 constrained-geometry inspired catalysts (CGCs). It was determined that the degree of separation of the amine sites could be controlled with protection/deprotection methods. Furthermore, an increase in the reactivity of the amines and the catalytic activity of CGCs built off of the amines was determined for aminosilicas synthesized by a protection/deprotection method. The second part of this work involved developing organic/inorganic hybrid materials as heterogeneous Bronsted acidic cocatalysts for activation of olefin polymerization precatalysts. This was the first reported organic

  14. Electrochemical degradation of trichloroacetic acid in aqueous media: influence of the electrode material.

    PubMed

    Esclapez, M D; Díez-García, M I; Sàez, V; Bonete, P; González-García, José

    2013-01-01

    The electrochemical degradation of trichloroacetic acid (TCAA) in water has been analysed through voltammetric studies with a rotating disc electrode and controlled-potential bulk electrolyses. The influence of the mass-transport conditions and initial concentration of TCAA for titanium, stainless steel and carbon electrodes has been studied. It is shown that the electrochemical reduction of TCAA takes place prior to the massive hydrogen evolution in the potential window for all electrode materials studied. The current efficiency is high (> 18%) compared with those normally reported in the literature, and the fractional conversion is above 50% for all the electrodes studied. Only dichloroacetic acid (DCAA) and chloride anions were routinely detected as reduction products for any of the electrodes, and reasonable values of mass balance error were obtained. Of the three materials studied, the titanium cathode gave the best results.

  15. Inhibition by hop bract polyphenols of cellular adherence and water-insoluble glucan synthesis of mutans streptococci.

    PubMed

    Tagashira, M; Uchiyama, K; Yoshimura, T; Shirota, M; Uemitsu, N

    1997-02-01

    The inhibitory effect of hop bract polyphenols (HBP) on cariogenic streptococci was investigated. It was found that the high molecular weight polyphenol (estimated about 36,000-40,000) inhibited the cellular adherence of Streptococcus mutans MT8148 (serotype C) and Streptococcus sobrinus ATCC 33478 (serotype g) at much small concentrations than the polyphenols extracted from oolong tea or green tea leaves. Furthermore, HBP also inhibited the action of glucosyltransferase, which was involved in the water-insoluble glucan synthesis, but did not suppress the growth and the acid production of the bacteria. These results suggest that HBP would be a candidate to act against dental caries caused by Mutans Streptococci.

  16. Boric acid corrosion of light water reactor pressure vessel head materials.

    SciTech Connect

    Park, J.-H.; Chopra, O. K.; Natesan, K.; Shack, W. J.; Cullen, Jr.; W. H.; Energy Technology; USNRC

    2005-01-01

    This work presents experimental data on electrochemical potential and corrosion rates for the materials found in the reactor pressure vessel head and control rod drive mechanism (CRDM) nozzles in boric acid solutions of varying concentrations at temperatures of 95-316 C. Tests were conducted in (a) high-temperature, high-pressure aqueous solutions with a range of boric acid concentrations, (b) high-temperature (150-316 C)H-B-Osolutions at ambient pressure, in wet and dry conditions, and (c) low-temperature (95 C) saturated, aqueous, boric acid solutions. These correspond to the following situations: (a) low leakage through the nozzle and nozzle/head annulus plugged, (b) low leakage through the nozzle and nozzle/head annulus open, and (c) significant cooling due to high leakage and nozzle/head annulus open. The results showed significant corrosion only for the low-alloy steel and no corrosion for Alloy 600 or 308 stainless steel cladding. Also, corrosion rates were significant in saturated boric acid solutions, and no material loss was observed in H-B-O solution in the absence of moisture. The results are compared with the existing corrosion/wastage data in the literature.

  17. The well-coordinated linkage between acidogenicity and aciduricity via insoluble glucans on the surface of Streptococcus mutans

    PubMed Central

    Guo, Lihong; McLean, Jeffrey S.; Lux, Renate; He, Xuesong; Shi, Wenyuan

    2015-01-01

    Streptococcus mutans is considered the principal cariogenic bacterium for dental caries. Despite the recognition of their importance for cariogenesis, the possible coordination among S. mutans’ main virulence factors, including glucan production, acidogenicity and aciduricity, has been less well studied. In the present study, using S. mutans strains with surface-displayed pH-sensitive pHluorin, we revealed sucrose availability- and Gtf functionality-dependent proton accumulation on S. mutans surface. Consistent with this, using a pH-sensitive dye, we demonstrated that both in vivo cell-produced and in vitro enzymatically synthesized insoluble glucans displayed proton-concentrating ability. Global transcriptomics revealed proton accumulation triggers the up-regulation of genes encoding functions involved in acid tolerance response in a glucan-dependent manner. Our data suggested that this proton enrichment around S. mutans could pre-condition the bacterium for acid-stress. Consistent with this hypothesis, we found S. mutans strains defective in glucan production were more acid sensitive. Our study revealed for the first time that insoluble glucans is likely an essential factor linking acidogenicity with aciduricity. The coordination of these key virulence factors could provide new insights on how S. mutans may have become a major cariogenic pathogen. PMID:26657939

  18. Screening for perfluoroalkyl acids in consumer products, building materials and wastes.

    PubMed

    Bečanová, Jitka; Melymuk, Lisa; Vojta, Šimon; Komprdová, Klára; Klánová, Jana

    2016-12-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a large group of important chemical compounds with unique and useful physico-chemical properties, widely produced and used in many applications. However, due to the toxicity, bioaccumulation and long-range transport potential of certain PFASs, they are of significant concern to scientists and policy makers. To assess human exposure to PFASs, it is necessary to understand the concentrations of these emerging contaminants in our environment, and particularly environments where urban population spend most of their time, i.e. buildings and vehicles. A total of 126 samples of building materials, consumer products, car interior materials and wastes were therefore analyzed for their content of key PFASs - 15 perfluoroalkyl acids (PFAAs). At least one of the target PFAAs was detected in 88% of all samples. The highest concentration of Σ15PFAAs was found in textile materials (77.61 μg kg(-1)), as expected, since specific PFAAs are known to be used for textile treatment during processing. Surprisingly, PFAAs were also detected in all analyzed composite wood building materials, which were dominated by perfluoroalkyl carboxylic acids with 5-8 carbons in the chain (Σ4PFCAs up to 32.9 μg kg(-1)). These materials are currently widely used for building refurbishment, and this is the first study to find evidence of the presence of specific PFASs in composite wood materials. Thus, in addition to consumer products treated with PFASs, materials used in the construction of houses, schools and office buildings may also play an important role in human exposure to PFASs.

  19. Biodegradable packaging materials conception based on starch and polylactic acid (PLA) reinforced with cellulose.

    PubMed

    Masmoudi, Fatma; Bessadok, Atef; Dammak, Mohamed; Jaziri, Mohamed; Ammar, Emna

    2016-10-01

    The plastic materials used for packaging are increasing leading to a considerable amount of undegradable solid wastes. This work deals with the reduction of conventional plastics waste and the natural resources preservation by using cellulosic polymers from renewable resources (alfa and luffa). Plasticized starch films syntheses were achieved at a laboratory scale. These natural films showed some very attractive mechanical properties at relatively low plasticizers levels (12 to 17 % by weight). Furthermore, mixtures including polylactic acid polymer (PLA) and cellulose fibers extracted from alfa and luffa were investigated by melt extrusion technique. When used at a rate of 10 %, these fibers improved the mixture mechanical properties. Both developed materials were biodegradable, but the plasticized starch exhibited a faster biodegradation kinetic compared to the PLA/cellulose fibers. These new materials would contribute to a sustainable development and a waste reduction.

  20. Carob pulp preparation rich in insoluble dietary fiber and polyphenols enhances lipid oxidation and lowers postprandial acylated ghrelin in humans.

    PubMed

    Gruendel, Sindy; Garcia, Ada L; Otto, Baerbel; Mueller, Corinna; Steiniger, Jochen; Weickert, Martin O; Speth, Maria; Katz, Norbert; Koebnick, Corinna

    2006-06-01

    Ghrelin is an orexigenic hormone that may affect substrate utilization in humans. Ghrelin is influenced by macronutrients, but the effects of insoluble dietary fiber and polyphenols are unknown. We investigated the effects of a polyphenol-rich insoluble dietary fiber preparation from carob pulp (carob fiber) on postprandial ghrelin responses and substrate utilization. Dose-dependent effects of the consumption of carob fiber were investigated in a randomized, single-blind, crossover study in 20 healthy subjects, aged 22-62 y. Plasma total and acylated ghrelin, triglycerides, and serum insulin and nonesterified fatty acids (NEFA) levels were repeatedly assessed before and after ingestion of an isocaloric standardized liquid meal with 0, 5, 10, or 20 g of carob fiber over a 300-min period. The respiratory quotient (RQ) was determined after consumption of 0 or 20 g of carob fiber. Carob fiber intake lowered acylated ghrelin to 49.1%, triglycerides to 97.2%, and NEFA to 67.2% compared with the control meal (P < 0.001). Total ghrelin and insulin concentrations were not affected by consumption of a carob fiber-enriched liquid meal. Postprandial energy expenditure was increased by 42.3% and RQ was reduced by 99.9% after a liquid meal with carob fiber compared with a control meal (P < 0.001). We showed that the consumption of a carob pulp preparation, an insoluble dietary fiber rich in polyphenols, decreases postprandial responses of acylated ghrelin, triglycerides, and NEFA and alters RQ, suggesting a change toward increased fatty acid oxidation. These results indicate that carob fiber might exert beneficial effects in energy intake and body weight.

  1. Conquering the control of insoluble and soluble starch with novel applications of amylase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The new knowledge that there is markedly more insoluble starch than previously considered in products across both the sugarcane factory and refinery has processing implications. This includes the application of a-amylases in the factory to control not only soluble but insoluble starch. Studies wer...

  2. Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

    PubMed

    Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

    2013-12-26

    A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) → Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) → V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) → Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine.

  3. A conservative interface-interaction model with insoluble surfactant

    NASA Astrophysics Data System (ADS)

    Schranner, Felix S.; Adams, Nikolaus A.

    2016-12-01

    In this paper we extend the conservative interface-interaction method of Hu et al. (2006) [34], adapted for weakly-compressible flows by Luo et al. (2015) [37], to include the effects of viscous, capillary, and Marangoni stresses consistently as momentum-exchange terms at the sharp interface. The interface-interaction method is coupled with insoluble surfactant transport which employs the underlying sharp-interface representation. Unlike previous methods, we thus achieve discrete global conservation in terms of interface interactions and a consistently sharp interface representation. The interface is reconstructed locally, and a sub-cell correction of the interface curvature improves the evaluation of capillary stresses and surfactant diffusion in particular for marginal mesh resolutions. For a range of numerical test cases we demonstrate accuracy and robustness of the method. In particular, we show that the method is at least as accurate as previous diffuse-interface models while exhibiting throughout the considered test cases improved computational efficiency. We believe that the method is attractive for high-resolution level-set interface-tracking simulations as it straightforwardly incorporates the effects of variable surface tension into the underlying conservative interface-interaction approach.

  4. Recovery of organic acids

    DOEpatents

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  5. Recovery of organic acids

    DOEpatents

    Verser, Dan W [Menlo Park, CA; Eggeman, Timothy J [Lakewood, CO

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  6. Naturally occurring radioactive material (NORM) from a former phosphoric acid processing plant.

    PubMed

    Beddow, H; Black, S; Read, D

    2006-01-01

    In recent years there has been an increasing awareness of the radiological impact of non-nuclear industries that extract and/or process ores and minerals containing naturally occurring radioactive material (NORM). These industrial activities may result in significant radioactive contamination of (by-) products, wastes and plant installations. In this study, scale samples were collected from a decommissioned phosphoric acid processing plant. To determine the nature and concentration of NORM retained in pipe-work and associated process plant, four main areas of the site were investigated: (1) the 'Green Acid Plant', where crude acid was concentrated; (2) the green acid storage tanks; (3) the Purified White Acid (PWA) plant, where inorganic impurities were removed; and (4) the solid waste, disposed of on-site as landfill. The scale samples predominantly comprise the following: fluorides (e.g. ralstonite); calcium sulphate (e.g. gypsum); and an assemblage of mixed fluorides and phosphates (e.g. iron fluoride hydrate, calcium phosphate), respectively. The radioactive inventory is dominated by 238U and its decay chain products, and significant fractionation along the series occurs. Compared to the feedstock ore, elevated concentrations (< or =8.8 Bq/g) of 238U were found to be retained in installations where the process stream was rich in fluorides and phosphates. In addition, enriched levels (< or =11 Bq/g) of 226Ra were found in association with precipitates of calcium sulphate. Water extraction tests indicate that many of the scales and waste contain significantly soluble materials and readily release radioactivity into solution.

  7. The development and amino acid binding ability of nano-materials based on azo derivatives: theory and experiment.

    PubMed

    Shang, Xuefang; Du, Jinge; Yang, Wancai; Liu, Yun; Fu, Zhiyuan; Wei, Xiaofang; Yan, Ruifang; Yao, Ningcong; Guo, Yaping; Zhang, Jinlian; Xu, Xiufang

    2014-05-01

    Two nano-material-containing azo groups have been designed and developed, and the binding ability of nano-materials with various amino acids has been characterized by UV-vis and fluorescence titrations. Results indicated that two nano-materials showed the strongest binding ability for homocysteine among twenty normal kinds of amino acids (alanine, valine, leucine, isoleucine, methionine, aspartic acid, glutamic acid, arginine, glycine, serine, threonine, asparagine, phenylalanine, histidine, tryptophan, proline, lysine, glutamine, tyrosine and homocysteine). The reason for the high sensitivity for homocysteine was that two nano-materials containing an aldehyde group reacted with SH in homocysteine and afforded very stable thiazolidine derivatives. Theoretical investigation further illustrated the possible binding mode in host-guest interaction and the roles of molecular frontier orbitals in molecular interplay. Thus, the two nano-materials can be used as optical sensors for the detection of homocysteine.

  8. Evaluation of oxygen pressurized microwave-assisted digestion of botanical materials using diluted nitric acid.

    PubMed

    Bizzi, Cezar Augusto; Barin, Juliano Smanioto; Müller, Edson Irineu; Schmidt, Lucas; Nóbrega, Joaquim A; Flores, Erico Marlon Moraes

    2011-02-15

    The feasibility of diluted nitric acid solutions for microwave-assisted decomposition of botanical samples in closed vessels was evaluated. Oxygen pressurized atmosphere was used to improve the digestion efficiency and Al, Ca, K, Fe, Mg and Na were determined in digests by inductively coupled plasma optical emission spectrometry (ICP OES). Efficiency of digestion was evaluated taking into account the residual carbon content (RCC) and residual acidity in digests. Samples were digested using nitric acid solutions (2, 3, 7, and 14 mol L(-1) HNO(3)) and the effect of gas phase composition inside the reaction vessels by purging the vessel with Ar (inert atmosphere, 1 bar), air (20% of oxygen, 1 bar) and pure O(2) (100% of oxygen, 1 bar) was evaluated. The influence of oxygen pressure was studied using pressures of 5, 10, 15 and 20 bar. It was demonstrated that a diluted nitric acid solution as low as 3 mol L(-1) was suitable for an efficient digestion of sample masses up to 500 mg of botanical samples using 5 bar of oxygen pressure. The residual acidities in final digests were lower than 45% in relation to the initial amount of acid used for digestion (equivalent to 1.3 mol L(-1) HNO(3)). The accuracy of the proposed procedure was evaluated using certified reference materials of olive leaves, apple leaves, peach leaves and pine needles. Using the optimized conditions for sample digestion, the results obtained were in agreement with certified values. The limit of quantification was improved up to a factor of 14.5 times for the analytes evaluated. In addition, the proposed procedure was in agreement with the recommendations of the green chemistry once it was possible to obtain relatively high digestion efficiency (RCC<5%) using only diluted HNO(3), which is important to minimize the generation of laboratory residues.

  9. Sialic Acid-Responsive Polymeric Interface Material: From Molecular Recognition to Macroscopic Property Switching

    PubMed Central

    Xiong, Yuting; Jiang, Ge; Li, Minmin; Qing, Guangyan; Li, Xiuling; Liang, Xinmiao; Sun, Taolei

    2017-01-01

    Biological systems that utilize multiple weak non-covalent interactions and hierarchical assemblies to achieve various bio-functions bring much inspiration for the design of artificial biomaterials. However, it remains a big challenge to correlate underlying biomolecule interactions with macroscopic level of materials, for example, recognizing such weak interaction, further transforming it into regulating material’s macroscopic property and contributing to some new bio-applications. Here we designed a novel smart polymer based on polyacrylamide (PAM) grafted with lactose units (PAM-g-lactose0.11), and reported carbohydrate-carbohydrate interaction (CCI)-promoted macroscopic properties switching on this smart polymer surface. Detailed investigations indicated that the binding of sialic acid molecules with the grafted lactose units via the CCIs induced conformational transformation of the polymer chains, further resulted in remarkable and reversible switching in surface topography, wettability and stiffness. With these excellent recognition and response capacities towards sialic acid, the PAM-g-lactose0.11 further facilitated good selectivity, strong anti-interference and high adsorption capacity in the capture of sialylated glycopeptides (important biomarkers for cancers). This work provides some enlightenment for the development of biointerface materials with tunable property, as well as high-performance glycopeptide enrichment materials. PMID:28084463

  10. Sialic Acid-Responsive Polymeric Interface Material: From Molecular Recognition to Macroscopic Property Switching

    NASA Astrophysics Data System (ADS)

    Xiong, Yuting; Jiang, Ge; Li, Minmin; Qing, Guangyan; Li, Xiuling; Liang, Xinmiao; Sun, Taolei

    2017-01-01

    Biological systems that utilize multiple weak non-covalent interactions and hierarchical assemblies to achieve various bio-functions bring much inspiration for the design of artificial biomaterials. However, it remains a big challenge to correlate underlying biomolecule interactions with macroscopic level of materials, for example, recognizing such weak interaction, further transforming it into regulating material’s macroscopic property and contributing to some new bio-applications. Here we designed a novel smart polymer based on polyacrylamide (PAM) grafted with lactose units (PAM-g-lactose0.11), and reported carbohydrate-carbohydrate interaction (CCI)-promoted macroscopic properties switching on this smart polymer surface. Detailed investigations indicated that the binding of sialic acid molecules with the grafted lactose units via the CCIs induced conformational transformation of the polymer chains, further resulted in remarkable and reversible switching in surface topography, wettability and stiffness. With these excellent recognition and response capacities towards sialic acid, the PAM-g-lactose0.11 further facilitated good selectivity, strong anti-interference and high adsorption capacity in the capture of sialylated glycopeptides (important biomarkers for cancers). This work provides some enlightenment for the development of biointerface materials with tunable property, as well as high-performance glycopeptide enrichment materials.

  11. Acid and enzymatic hydrolysis of pretreated cellulosic materials as an analytical tool

    SciTech Connect

    Ladisch, C.M.; Chiasson, C.M.; Tsao, G.T.

    1982-07-01

    A rapid and accurate procedure for the quantitative analysis of cellulose in textiles based on acid and enzymatic hydrolysis was investigated. Total hydrolysis was achieved by a two-step procedure: the cellulose in the sample was first dissolved in cadoxen and then reprecipitated. The material, thus pretreated, was then hydrolyzed with acid or enzyme catalytic agents. Hydrolysis products were detected and quantified by colorimetric, enzymic, and liquid chromatographic methods of analysis. Samples examined included cotton, rayon, Avicel, CF-11, and cotton/polyester blends. The specificity of the enzyme hydrolysis method allowed analysis of raw cotton without prior purification. Results of the analyses were compared to those obtained by existing methods of analysis.

  12. Method for acid oxidation of radioactive, hazardous, and mixed organic waste materials

    DOEpatents

    Pierce, Robert A.; Smith, James R.; Ramsey, William G.; Cicero-Herman, Connie A.; Bickford, Dennis F.

    1999-01-01

    The present invention is directed to a process for reducing the volume of low level radioactive and mixed waste to enable the waste to be more economically stored in a suitable repository, and for placing the waste into a form suitable for permanent disposal. The invention involves a process for preparing radioactive, hazardous, or mixed waste for storage by contacting the waste starting material containing at least one organic carbon-containing compound and at least one radioactive or hazardous waste component with nitric acid and phosphoric acid simultaneously at a contacting temperature in the range of about 140.degree. C. to about 210 .degree. C. for a period of time sufficient to oxidize at least a portion of the organic carbon-containing compound to gaseous products, thereby producing a residual concentrated waste product containing substantially all of said radioactive or inorganic hazardous waste component; and immobilizing the residual concentrated waste product in a solid phosphate-based ceramic or glass form.

  13. Effect of Different Electrode Materials on the Electropolymerization Process of Aniline in Nitric Acid Media

    NASA Astrophysics Data System (ADS)

    Li, Yaozong; Yi, Yun; Yang, Weifang; Liu, Xiaoqing; Li, Yuanyuan; Wang, Wei

    2017-02-01

    The electropolymerization process of aniline on different electrode surfaces such as Pt, Au, RuTi and polyaniline film in nitric acid solution containing 1 M aniline was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Proposed electrical equivalent circuits were used to give a further analysis. Results show that the electrode materials accelerate the aniline electropolymerization remarkably as a catalyst, especially the electrochemical oxidation process of monomer aniline to its cation radical, which is the key step to incur the electropolymerization reaction of aniline on the electrode surface. The polymerization of aniline on RuTi electrode has the lowest reaction resistance for its adsorption sites, and the catalytic effects of these different electrodes decrease in the order: RuTi > polyaniline film > Pt > Au. The results also show that several states of polyaniline films are formed during the potential linear scan process in nitric acid solution and the corresponding oxidation and reduction reaction are reversible.

  14. Probing the mechanisms of drug release from amorphous solid dispersions in medium-soluble and medium-insoluble carriers.

    PubMed

    Sun, Dajun D; Lee, Ping I

    2015-08-10

    The objective of the current study is to mechanistically differentiate the dissolution and supersaturation behaviors of amorphous drugs from amorphous solid dispersions (ASDs) based on medium-soluble versus medium-insoluble carriers under nonsink dissolution conditions through a direct head-to-head comparison. ASDs of indomethacin (IND) were prepared in several polymers which exhibit different solubility behaviors in acidic (pH1.2) and basic (pH7.4) dissolution media. The selected polymers range from water-soluble (e.g., PVP and Soluplus) and water-insoluble (e.g., ethylcellulose and Eudragit RL PO) to those only soluble in an acidic or basic dissolution medium (e.g., Eudragit E100, Eudragit L100, and HPMCAS). At 20wt.% drug loading, DSC and powder XRD analysis confirmed that the majority of incorporated IND was present in an amorphous state. Our nonsink dissolution results confirm that whether the carrier matrix is medium soluble determines the release mechanism of amorphous drugs from ASD systems which has a direct impact on the rate of supersaturation generation, thus in turn affecting the evolution of supersaturation in amorphous systems. For example, under nonsink dissolution conditions, the release of amorphous IND from medium-soluble carriers is governed by a dissolution-controlled mechanism leading to an initial surge of supersaturation followed by a sharp decline in drug concentration due to rapid nucleation and crystallization. In contrast, the dissolution of IND ASD from medium-insoluble carriers is more gradual as drug release is regulated by a diffusion-controlled mechanism by which drug supersaturation is built up gradually and sustained over an extended period of time without any apparent decline. Since several tested carrier polymers can be switched from soluble to insoluble by simply changing the pH of the dissolution medium, the results obtained here provide unequivocal evidence of the proposed transition of kinetic solubility profiles from the

  15. Evaporation of Sessile Droplets Laden with Particles and Insoluble Surfactants.

    PubMed

    Karapetsas, George; Chandra Sahu, Kirti; Matar, Omar K

    2016-07-12

    We consider the flow dynamics of a thin evaporating droplet in the presence of an insoluble surfactant and noninteracting particles in the bulk. On the basis of lubrication theory, we derive a set of evolution equations for the film height, the interfacial surfactant, and bulk particle concentrations, taking into account the dependence of liquid viscosity on the local particle concentration. An important ingredient of our model is that it takes into account the fact that the surfactant adsorbed at the interface hinders evaporation. We perform a parametric study to investigate how the presence of surfactants affects the evaporation process as well as the flow dynamics with and without the presence of particles in the bulk. Our numerical calculations show that the droplet lifetime is affected significantly by the balance between the ability of the surfactant to enhance spreading, suppressing the effect of thermal Marangoni stresses-induced motion, and to hinder the evaporation flux through the reduction of the effective interfacial area of evaporation, which tend to accelerate and decelerate the evaporation process, respectively. For particle-laden droplets and in the case of dilute solutions, the droplet lifetime is found to be weakly dependent on the initial particle concentration. We also show that the particle deposition patterns are influenced strongly by the direct effect of the surfactant on the evaporative flux; in certain cases, the "coffee-stain" effect is enhanced significantly. A discussion of the delicate interplay between the effects of capillary pressure and solutal and thermal Marangoni stresses, which drive the liquid flow inside of the evaporating droplet giving rise to the observed results, is provided herein.

  16. Proteome analysis of the triton-insoluble erythrocyte membrane skeleton.

    PubMed

    Basu, Avik; Harper, Sandra; Pesciotta, Esther N; Speicher, Kaye D; Chakrabarti, Abhijit; Speicher, David W

    2015-10-14

    Erythrocyte shape and membrane integrity is imparted by the membrane skeleton, which can be isolated as a Triton X-100 insoluble structure that retains the biconcave shape of intact erythrocytes, indicating isolation of essentially intact membrane skeletons. These erythrocyte "Triton Skeletons" have been studied morphologically and biochemically, but unbiased proteome analysis of this substructure of the membrane has not been reported. In this study, different extraction buffers and in-depth proteome analyses were used to more fully define the protein composition of this functionally critical macromolecular complex. As expected, the major, well-characterized membrane skeleton proteins and their associated membrane anchors were recovered in good yield. But surprisingly, a substantial number of additional proteins that are not considered in erythrocyte membrane skeleton models were recovered in high yields, including myosin-9, lipid raft proteins (stomatin, flotillin1 and 2), multiple chaperone proteins (HSPs, protein disulfide isomerase and calnexin), and several other proteins. These results show that the membrane skeleton is substantially more complex than previous biochemical studies indicated, and it apparently has localized regions with unique protein compositions and functions. This comprehensive catalog of the membrane skeleton should lead to new insights into erythrocyte membrane biology and pathogenic mutations that perturb membrane stability. Biological significance Current models of erythrocyte membranes describe fairly simple homogenous structures that are incomplete. Proteome analysis of the erythrocyte membrane skeleton shows that it is quite complex and includes a substantial number of proteins whose roles and locations in the membrane are not well defined. Further elucidation of interactions involving these proteins and definition of microdomains in the membrane that contain these proteins should yield novel insights into how the membrane skeleton

  17. Improving stable carbon and oxygen isotope geochemical measurements in dolomite: reference material and acid fractionation factor

    NASA Astrophysics Data System (ADS)

    Vandeginste, V.; John, C. M.; Jourdan, A.; Davis, S.

    2010-12-01

    The analysis of stable carbon and oxygen isotope composition is one of the most commonly used techniques in stratigraphic and diagenetic research of carbonate rocks. The wide-spread use and easy access of this long-established method has the side effect that little attention is paid to fundamental calibrations. Dolomite is often measured against a calcite standard (NBS19), and the acid fractionation factor used to calibrate is based on the one for calcite. To date, no reference material exists for dolomite. In this study, which is part of dolomite research in the Qatar Carbonates and Carbon Storage Research Centre project, we focus on two main goals. First, we characterize a current standard of dolomite used for major and minor elemental geochemistry, and assess its suitability as a new dolomite standard for δ18O and δ13C. Second, we attempt to better constrain the acid fractionation factor for dolomite and assess the influence of different dolomite types on this fractionation factor. As only two third of the total oxygen in the carbonate is released in the form of CO2 during acid reaction, a fractionation between the reacting carbonate and the resulting gas will occur. A recent study by Kim et al. (2007) improved on the acid fractionation factors for calcite and aragonite. Often, the acid fractionation factor for dolomite is used to calculate δ18O and δ13C from the values obtained by calibration with the calcite standard. Only two studies (from the 1980’s) have attempted to constrain the acid fractionation factor for dolomite, of which only Rosenbaum and Sheppard (1986) did experiments not only at 25°C, but also at 50 and 100°C. The dataset of the latter authors is, however, very limited and contains only two dolomite samples. We aim at improving the constraints on the acid fractionation factor of dolomite by reacting a wide range of different types of dolomite at a wide range of acid temperature, and compare this to the absolute isotopic composition of

  18. Modelling of the nitric acid reduction process: Application to materials behavior in reprocessing plants

    SciTech Connect

    Sicsic, D.; Balbaud-Celerier, F.; Tribollet, B.

    2012-07-01

    In France, the recycling process of nuclear waste fuels involves the use of hot concentrated nitric acid. The understanding and the prediction of the structural materials (mainly austenitic stainless steels) behaviour requires the determination of the nitric acid reduction process. Nitric acid is indirectly reduced by an autocatalytic mechanism depending on the cathodic overpotential and the acid concentration. This mechanism has been widely studied. All the authors agree on its autocatalytic nature, characterized by the predominant role of the reduction products. It is also generally admitted that nitric acid or the nitrate ion are not the electro-active species. However, uncertainties remain concerning the nature of the electro-active species, the place where the catalytic species regenerates and the thermodynamic and kinetic behaviour of the reaction intermediates. The aim of this study is to clarify some of these uncertainties by performing an electrochemical investigation of the 4 mol.L -1 nitric acid reduction process at 40 deg. C occurring on an inert electrode (platinum or gold). An inert electrode was chosen as a working electrode in a first step in order to avoid its oxidation and focus the research on the reduction mechanism. This experimental work enabled to suggest a coherent sequence of electrochemical and chemical reactions. Then, a kinetic modelling of this sequence was carried out for a gold rotating disk system. In this objective, a thermodynamic study at 25 deg. C led to the evaluation of the composition of liquid and gaseous phases for nitric acid solutions from 0.5 to 22 mol.L -1. The kinetics of the reduction process of nitric acid 4 mol.L -1 was investigated by cyclic voltammetry and chrono-amperometry on an inert electrode at 40 deg. C. A coupling of chrono-amperometry and FTIR in gaseous phase led to the identification of the gaseous reduction products as a function of the cathodic overpotential. These different results showed that for

  19. Humic acid-like material from sewage sludge stimulates culture growth of ectomycorrhizal fungi in vitro.

    PubMed

    Hrselová, H; Soukupová, L; Gryndler, M

    2007-01-01

    Significant effects of humic acid-like material (HALM) extracted from sewage sludge on dry matter production of cultures of ectomycorrhizal basidiomycetes were found in vitro. Mycelial growth of the majority of isolates tended to increase in the presence of the HALM and this effect was significant for 6 isolates. Strongest stimulation was observed in the case of Amanita muscaria, Leccinum aurantiacum and Lactarius deterrimus. The results suggest that the HALM can be used as an additive to media for cultivation of ectomycorrhizal basidiomycetes.

  20. Economic and environmental assessment of propionic acid production by fermentation using different renewable raw materials.

    PubMed

    Tufvesson, Pär; Ekman, Anna; Sardari, Roya R R; Engdahl, Kristina; Tufvesson, Linda

    2013-12-01

    Production of propionic acid by fermentation of glycerol as a renewable resource has been suggested as a means for developing an environmentally-friendly route for this commodity chemical. However, in order to quantify the environmental benefits, life cycle assessment of the production, including raw materials, fermentation, upstream and downstream processing is required. The economic viability of the process also needs to be analysed to make sure that any environmental savings can be realised. In this study an environmental and economic assessment from cradle-to-gate has been conducted. The study highlights the need for a highly efficient bioprocess in terms of product titre (more than 100g/L and productivity more than 2g/(L · h)) in order to be sustainable. The importance of the raw materials and energy production for operating the process to minimize emissions of greenhouse gases is also shown.

  1. Removal of Basic Violet 14 from aqueous solution using sulphuric acid activated materials.

    PubMed

    Suresh, S

    2016-01-01

    In this study the adsorption of Basic Violet, 14 from aqueous solution onto sulphuric acid activated materials prepared from Calophyllum inophyllum (CS) and Theobroma cacao (TS) shells were investigated. The experimental data were analysed by Langmuir, Freundlich and Temkin isotherm models. The results showed that CS has a superior adsorption capacity compared to the TS. The adsorption capacity was found to be 1416.43 mg/g for CS and 980.39 mg/g for TS. The kinetic data results at different concentrations were analysed using pseudo first-order and pseudo-second order model. Boyd plot indicates that the dye adsorption onto CS and TS is controlled by film diffusion. The adsorbents were characterised by scanning electron microscopy. The materials used in this study were economical waste products and hence can be an attractive alternative to costlier adsorbents for dye removal in industrial wastewater treatment processes.

  2. Chemical Modeling of Acid-Base Properties of Soluble Biopolymers Derived from Municipal Waste Treatment Materials

    PubMed Central

    Tabasso, Silvia; Berto, Silvia; Rosato, Roberta; Tafur Marinos, Janeth Alicia; Ginepro, Marco; Zelano, Vincenzo; Daniele, Pier Giuseppe; Montoneri, Enzo

    2015-01-01

    This work reports a study of the proton-binding capacity of biopolymers obtained from different materials supplied by a municipal biowaste treatment plant located in Northern Italy. One material was the anaerobic fermentation digestate of the urban wastes organic humid fraction. The others were the compost of home and public gardening residues and the compost of the mix of the above residues, digestate and sewage sludge. These materials were hydrolyzed under alkaline conditions to yield the biopolymers by saponification. The biopolymers were characterized by 13C NMR spectroscopy, elemental analysis and potentiometric titration. The titration data were elaborated to attain chemical models for interpretation of the proton-binding capacity of the biopolymers obtaining the acidic sites concentrations and their protonation constants. The results obtained with the models and by NMR spectroscopy were elaborated together in order to better characterize the nature of the macromolecules. The chemical nature of the biopolymers was found dependent upon the nature of the sourcing materials. PMID:25658795

  3. Novel cross-linked alcohol-insoluble solid (CL-AIS) affinity gel from pea pod for pectinesterase purification.

    PubMed

    Wu, Ming-Chang; Lin, Guan-Hui; Wang, Yuh-Tai; Jiang, Chii-Ming; Chang, Hung-Min

    2005-10-05

    Alcohol-insoluble solids (AIS) from pea pod were cross-linked (CL-AIS) and used as an affinity gel matrix to isolate pectin esterases (PEs) from tendril shoots of chayote (TSC) and jelly fig achenes (JFA), and the results were compared with those isolated by ion-exchange chromatography with a commercial resin. CL-AIS gel matrix in a column displayed poor absorption and purification fold of PE; however, highly methoxylated CL-AIS (HM-CL-AIS), by exposing CL-AIS to methanolic sulfuric acid to increase the degree of esterification (DE) to 92%, facilitated the enzyme purification. The purified TSC PE and JFA PE by the HM-CL-AIS column were proofed as a single band on an SDS-PAGE gel, showing that the HM-CL-AIS column was a good matrix for purification of PE, either with alkaline isoelectric point (pI) (TSC PE) or with acidic pI (JFA PE).

  4. Topical fluoride application is able to reduce acid susceptibility of restorative materials.

    PubMed

    Yu, Hao; Buchalla, Wolfgang; Cheng, Hui; Wiegand, Annette; Attin, Thomas

    2012-01-01

    This study aimed to investigate the effect of topical fluoride application on the acid susceptibility of restorative materials. Four restorative materials were investigated in this study: 2 composite resins (Tetric EvoCeram and Filtek Silorane), a polyacid-modified resin composite (Dyract Extra), and a conventional glass-ionomer cement (Ketac Fil Plus). The samples were treated once with 1 of 8 different fluoride solutions (TiF4, NaF, AmF, and SnF2, each at native pH or pH 4) for 3 min or remained untreated (control). The samples were then eroded by citric acid (pH 2.6) for 5 days (6×1 min daily). Erosive substance loss, surface topographic and compositional changes were investigated using surface profilometry, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), respectively, after fluoride pretreatment and after erosion. The results indicate high-concentrated AmF solution at native pH was effective in inhibiting erosion in the conventional glass-ionomer cement and polyacid-modified resin composite.

  5. Novel conducting polymer-heteropoly acid hybrid material for artificial photosynthetic membranes.

    PubMed

    McDonald, Michael B; Freund, Michael S

    2011-04-01

    Artificial photosynthetic (AP) approaches to convert and store solar energy will require membranes capable of conducting both ions and electrons while remaining relatively transparent and chemically stable. A new approach is applied herein involving previously described in situ chemical polymerization of electronically conducting poly(3,4-ethylenedioxythiophene) (PEDOT) in the presence of proton conducting heteropoly acid (HPA) phosphomolybdic acid (PMA). The electrochemical behaviour of the PEDOT/PMA hybrid material was investigated and it was found that the conducting polymer (CP) is susceptible to irreversible oxidative processes at potentials where water is oxidized. This will be problematic in AP devices should the process occur in very close proximity to a conducting polymer-based membrane. It was found that PEDOT grants the system good electrical performance in terms of conductivity and stability over a large pH window; however, the presence of PMA was not found to provide sufficient proton conductivity. This was addressed in an additional study by tuning the ionic (and in turn, electronic) conductivity in creating composites with the proton-permselective polymer Nafion. It was found that a material of this nature with near-equal conductivity for optimal chemical conversion efficiency will consist of roughly three parts Nafion and one part PEDOT/PMA.

  6. Cross-linked polystyrene sulfonic acid and polyethylene glycol as a low-fouling material.

    PubMed

    Alghunaim, Abdullah; Zhang Newby, Bi-min

    2016-04-01

    A negatively charged hydrophilic low fouling film was prepared by thermally cross-linking a blend consisting of polystyrene sulfonic acid (PSS) and polyethylene glycol (PEG). The film was found to be stable by dip-washing. The fouling resistance of this material toward bacterial (Escherichia coli) and colloidal (polystyrene particles) attachment, non-specific protein (fibronectin) adsorption and cell (3T3 NIH) adhesion was evaluated and was compared with glass slides modified with polyethylene glycol (PEG) brushes, oxidized 3-mercaptopropyltrimethoxysilane (sulfonic acid, SA), and n-octadecyltrichlorosilane (OTS). The extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory and thermodynamic models based on surface energy were used to explain the interaction behaviors of E. coli/polystyrene particles-substrate and protein-substrate interactions, respectively. The cross-linked PSS-PEG film was found to be slightly better than SA and PEG toward resisting non-specific protein adsorption, and showed comparable low attachment results as those of PEG toward particle, bacterial and NIH-3T3 cells adhesion. The low-fouling performance of PSS-PEG, a cross-linked film by a simple thermal curing process, could allow this material to be used for applications in aqueous environments, where most low fouling hydrophilic polymers, such as PSS or PEG, could not be easily retained.

  7. Amphiphilic poly(L-amino acids) - new materials for drug delivery.

    PubMed

    Lalatsa, Aikaterini; Schätzlein, Andreas G; Mazza, Mariarosa; Le, Thi Bich Hang; Uchegbu, Ijeoma F

    2012-07-20

    The formulation of drug compounds into medicines will increasingly rely on the use of specially tailored molecules, which fundamentally alter the drug's pharmacokinetics to enable its therapeutic activity. This is particularly true of the more challenging hydrophobic drugs or therapeutic biological molecules. The demand for such enabled medicines will translate into a demand for advanced highly functionalised drug delivery materials. Polymers have been used to formulate medicines for many decades and this is unlikely to change soon. Amphiphilic polymers based on amino acids are the subject of this review. These molecules, which present as either poly(L-amino acid) block copolymers or poly(L-amino acid) backbones with hydrophobic substituents, self assemble into micelles, vesicles, nanofibres and solid nanoparticles and such self assemblies, have drug delivery capabilities. The nature of the self-assembly depends on the chemistry of the constituent molecules, with the more hydrophilic molecules forming nanosized micellar aggregates including peptide nanofibres, molecules of intermediate hydrophobicity forming polymeric vesicles and the more hydrophobic variants forming amorphous polymeric nanoparticles of 100-1000 nm in diameter. The self-assemblies may be loaded with drugs or may present as micelle forming polymer-drug conjugates and the supramolecular aggregates have been employed as drug solubilisers, tumour targeting agents, gene delivery vectors and facilitators of intracellular drug uptake, with a more promising polymer-drug conjugate progressing to clinical testing.

  8. Comparison of water solubility enhancements of organic solutes by aquatic humic materials and commercial humic acids

    SciTech Connect

    Chiou, C.T.; Kile, D.E.; Brinton, T.I.; Malcolm, R.L.; Leenheer, J.A.; MacCarthy, P.

    1987-12-01

    Water solubility enhancements of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (p,p'-DDT), 2,4,5,2',5'-pentachlorobiphenyl (2,4,5,2',5'-PCB), and 2,4,4'-trichlorobiphenyl (2,4,4'-PCB) by dissolved organic matter have been studied with the following samples: (1) acidic water samples from the Suwannee River, Georgia, and the Sopchoppy River, Florida; (2) a humic extract of a nearly neutral pH water from the Calcasieu River, Louisiana; (3) commercial humic acids from the Aldrich Chemical Co. and Fluka-Tridom Chemical Corp. The calculated partition coefficients on a dissolved organic carbon basis (K/sub doc/) for organic solutes with water samples and aquatic humic extracts from this and earlier studies indicate that the enhancement effect varies with the molecular composition of the aquatic humic materials, The K/sub doc/ values with water and aquatic humic samples are, however, far less than the observed K/sub doc/ values obtained with the two commercial samples, by factors of about 4-20. In view of this finding, one should be cautious in interpreting the effects of the dissolved organic matter on solubility enhancement of organic solutes on the basis of the use of commercial humic acids. 14 references, 3 figures, 2 tables.

  9. Preparation and characterization of dry method esterified starch/polylactic acid composite materials.

    PubMed

    Zuo, Yingfeng; Gu, Jiyou; Yang, Long; Qiao, Zhibang; Tan, Haiyan; Zhang, Yanhua

    2014-03-01

    Corn starch and maleic anhydride were synthesized from a maleic anhydride esterified starch by dry method. Fourier transform infrared spectroscopy (FTIR) was used for the qualitative analysis of the esterified starches. The reaction efficiency of dry method esterified starch reached 92.34%. The dry method esterified starch was blended with polylactic acid (PLA), and the mixture was melted and extruded to produce the esterified starch/polylactic acid (ES/PLA) composites. The degree of crystallinity of the ES/PLA was lower than that of the NS/PLA, indicating that the relative dependence between these two components of starch and polylactic acid was enhanced. Scanning electron microscopy (SEM) indicated that the dry method esterified starch increased the two-phase interface compatibility of the composites, thereby improving the tensile strength, bending strength, and elongation at break of the ES/PLA composite. The introduction of a hydrophobic ester bond and increase in interface compatibility led to an increase in ES/PLA water resistance. Melt index determination results showed that starch esterification modification had improved the melt flow properties of starch/PLA composite material. Strain scanning also showed that the compatibility of ES/PLA was increased. While frequency scanning showed that the storage modulus and complex viscosity of ES/PLA was less than that of NS/PLA.

  10. Improvement of β-TCP/PLLA biodegradable material by surface modification with stearic acid.

    PubMed

    Ma, Fengcang; Chen, Sai; Liu, Ping; Geng, Fang; Li, Wei; Liu, Xinkuan; He, Daihua; Pan, Deng

    2016-05-01

    Poly-L-lactide (PLLA) is a biodegradable polymer and used widely. Incorporation of beta tricalcium phosphate (β-TCP) into PLLA can enhance its osteoinductive properties. But the interfacial layer between β-TCP particles with PLLA matrix is easy to be destroyed due to inferior interfacial compatibility of the organic/inorganic material. In this work, a method of β-TCP surface modification with stearic acid was investigated to improve the β-TCP/PLLA biomaterial. The effects of surface modification on the β-TCP were investigated by FTIR, XPS, TGA and CA. It was found that the stearic acid reacted with β-TCP and oxhydryl was formed during the surface modification. Hydrophilicity of untreated or modified β-TCP/PLLA composite was increased by the addition of 10 wt.% β-TCP, but it decreased as the addition amount increased from 10 wt.% to 20 wt.%. Two models were suggested to describe the effect of β-TCP concentration on CA of the composites. Mechanical properties of β-TCP/PLLA composites were tested by bending and tensile tests. Fractures of the composites after mechanical test were observed by SEM. It was found that surface modification with stearic acid improved bending and tensile strengths of the β-TCP/PLLA composites obviously. The SEM results indicated that surface modification decreased the probability of interface debonding between fillers and matrix under load.

  11. Autonomous healing materials based on epoxidized natural rubber and ethylene methacrylic acid ionomers

    NASA Astrophysics Data System (ADS)

    Arifur Rahman, Md; Penco, Maurizio; Peroni, Isabella; Ramorino, Giorgio; Janszen, Gerardus; Di Landro, Luca

    2012-03-01

    The development of autonomous healing material has an enormous scientific and technological interest. In this context, this research work deals with the investigation of autonomous healing behavior of epoxidized natural rubber (ENR) and its blends with ethylene methacrylic acid ionomers. The autonomous healing behavior of ENR and its blends containing two different ionomers [poly(ethylene-co-methacrylic acid sodium salt) (EMNa) and poly(ethylene-co-methacrylic acid zinc salt) (EMZn)] has been studied by ballistic puncture tests. Interestingly, EMNa/ENR blends exhibit complete healing just after the ballistic test but EMZn/ENR blends do not show full self-repairing. The healing efficiency has been evaluated by optical microscopy and a depressurized air-flow test. The healing mechanism has been investigated by characterizing thermal and mechanical properties of the blends. The chemical structure studied by FTIR and thermal analysis show that the ion content of ionomers and functionality of ENR has a significant influence on the self-healing behavior.

  12. Thermal Characterization of Lauric-Stearic Acid/Expanded Graphite Eutectic Mixture as Phase Change Materials.

    PubMed

    Zhu, Hua; Zhang, Peng; Meng, Zhaonan; Li, Ming

    2015-04-01

    The eutectic mixture of lauric acid (LA) and stearic acid (SA) is a desirable phase change material (PCM) due to the constant melting temperature and large latent heat. However, its poor thermal conductivity has hampered its broad utilization. In the present study, pure LA, SA and the mixtures with various mass fractions of LA-SA were used as the basic PCMs, and 10 wt% expanded graphite (EG) was added to enhance the thermal conductivities. The phase change behaviors, microstructural analysis, thermal conductivities and thermal stabilities of the mixtures of PCMs were investigated by differential scanning calorimetry (DSC), scanning electronic microscope (SEM), transient plane source (TPS) and thermogravimetric analysis (TGA), respectively. The results show that the LA-SA binary mixture of mixture ratio of 76.3 wt%: 23.7 wt% forms an eutectic mixture, which melts at 38.99 °C and has a latent heat of 159.94 J/g. The melted fatty acids are well absorbed by the porous network of EG and they have a good thermal stability. Furthermore, poor thermal conductivities can be well enhanced by the addition of EG.

  13. Development of palm-based reference materials for the quantification of fatty acids composition.

    PubMed

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai; Kuntom, Ainie

    2008-01-01

    Characterisation of fatty acids composition of three palm-based reference materials was carried out through inter-laboratory proficiency tests. Twelve laboratories collaborated in these tests and the fatty acids compositions of palm oil, palm olein and palm stearin were determined by applying the MPOB Test Methods p3.4:2004 and p3.5:2004. Determination of consensus values and their uncertainties were based on the acceptable statistical agreement of results obtained from the collaborating laboratories. The consensus values and uncertainties (%) for each palm oil reference material produced are listed as follows : 0.20% (C12:0), 1.66+/-0.05% (C14:0), 43.39+/-0.39% (C16:0), 0.14+/-0.06% (C16:1), 3.90+/-0.11% (C18:0), 40.95+/-0.23% (C18:1), 9.68+/-0.21% (C18:2), 0.16+/-0.07% (C18:3) and 0.31+/-0.08% (C20:0) for fatty acids composition of palm oil; 0.23+/-0.04% (C12:0), 1.02+/-0.04% (C14:0), 39.66+/-0.19% (C16:0), 0.18+/-0.07% (C16:1), 3.81+/-0.04% (C18:0), 44.01+/-0.08% (C18:1), 10.73+/-0.08% (C18:2), 0.20+/-0.06% (C18:3) and 0.34+/-0.04% (C20:0) for fatty acids composition of palm olein; and 0.20% (C12:0), 1.14+/-0.05% (C14:0), 49.42+/-0.25% (C16:0), 0.16+/-0.08% (C16:1), 4.15+/-0.10% (C18:0), 36.14+/-0.77% (C18:1), 7.95+/-0.29% (C18:2), 0.11+/-0.07% (C18:3) and 0.30+/-0.08% (C20:0) for fatty acids composition of palm stearin.

  14. Novel proteins identified in the insoluble byssal matrix of the freshwater zebra mussel.

    PubMed

    Gantayet, Arpita; Rees, David J; Sone, Eli D

    2014-04-01

    The freshwater zebra mussel, Dreissena polymorpha, is an invasive, biofouling species that adheres to a variety of substrates underwater, using a proteinaceous anchor called the byssus. The byssus consists of a number of threads with adhesive plaques at the tips. It contains the unusual amino acid 3, 4-dihydroxyphenylalanine (DOPA), which is believed to play an important role in adhesion, in addition to providing structural integrity to the byssus through cross-linking. Extensive DOPA cross-linking, however, renders the zebra mussel byssus highly resistant to protein extraction, and therefore limits byssal protein identification. We report here on the identification of seven novel byssal proteins in the insoluble byssal matrix following protein extraction from induced, freshly secreted byssal threads with minimal cross-linking. These proteins were identified by LC-MS/MS analysis of tryptic digests of the matrix proteins by spectrum matching against a zebra mussel cDNA library of genes unique to the mussel foot, the organ that secretes the byssus. All seven proteins were present in both the plaque and thread. Comparisons of the protein sequences revealed common features of zebra mussel byssal proteins, and several recurring sequence motifs. Although their sequences are unique, many of the proteins display similarities to marine mussel byssal proteins, as well as to adhesive and structural proteins from other species. The large expansion of the byssal proteome reported here represents an important step towards understanding zebra mussel adhesion.

  15. Molecular organization of a water-insoluble iridium(III) complex in mixed monolayers.

    PubMed

    Giner-Casares, Juan J; Pérez-Morales, Marta; Bolink, Henk J; Muñoz, Eulogia; de Miguel, Gustavo; Martín-Romero, María T; Camacho, Luis

    2007-11-01

    In this work, organized mixed monolayers containing a cationic water-insoluble iridium(III) complex, Ir-dye, [Ir(ppy)(2)(tmphen)]PF(6), (tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline, and ppy = 2-phenylpyridine), and an anionic lipid matrix, DMPA, dimyristoyl-phosphatidic acid, with different molar proportions, were formed by the co-spreading method at the air-water interface. The presence of the dye at the interface, as well as the molecular organization of the mixed films, is deduced from surface techniques such as pi-A isotherms, Brewster angle microscopy (BAM) and reflection spectroscopy. The results obtained remark the formation of an equimolar mixed film, Ir-dye/DMPA = 1:1. BAM images reveal a whole homogeneous monolayer, with gradually increasing reflectivity along the compression process up to reaching the collapse of this equimolecular monolayer at pi approximately equal to 37 mNm(-1). Increasing the molar ratio of DMPA in the mixture, the excess of lipid molecules organizes themselves forming dark flower-like domains of pure DMPA at high surface pressures, coexisting with the mixed Ir-dye/DMPA = 1:1 monolayer. On the other hand, unstable mixed monolayers are obtained by using an initial dye surface concentration higher than the equimolecular one. These mixed Langmuir monolayers have been successfully transferred onto solid substrates by the LB (Langmuir-Blodgett) technique.

  16. Dielectric properties tangential to the interface in model insoluble monolayers: theoretical assessment.

    PubMed

    Shushkov, Philip G; Tzvetanov, Stanislav A; Ivanova, Anela N; Tadjer, Alia V

    2008-05-06

    Studies of insoluble monolayers built of phospholipids and various long-chained fatty acids or their glycerin esters are the major source for what is currently known about the relationship between monolayer composition and physicochemical properties. The surface pressure, dipole moment, dielectric permittivity, polarizability, refractivity, and other electrical and optical features are governed by the surfactant structural specificity and solvent organization at the microscopic level. To provide insight into the atomistic details of the interfacial structure, model monolayers at the air/water interface of two distinctly different in composition and isotherm profile surfactants are investigated by means of molecular dynamics all-atom simulations. Analysis of the computational results allows the estimation of empirically unattainable quantities such as tangential (di)electric properties, their decomposition to surfactant and water contributions, and their relationship with the changes in interfacial molecular organization at different surface concentrations. The employed theoretical approach provides a comprehensive description of interfacial phenomena at the molecular level where the traditional phenomenological investigations are ineffective.

  17. Blends of enteric and GIT-insoluble polymers used for film coating: physicochemical characterization and drug release patterns.

    PubMed

    Lecomte, F; Siepmann, J; Walther, M; MacRae, R J; Bodmeier, R

    2003-05-20

    THE OBJECTIVES OF THIS STUDY WERE: (i). to use blends of gastrointestinal tract (GIT)-insoluble and enteric polymers (ethyl cellulose and Eudragit L) as coating materials for multiparticulate controlled release dosage forms; (ii). to investigate the effects of the polymer blend ratio and coating level on the resulting drug release patterns; and (iii). to explain the observed phenomena based on the physicochemical properties of the systems. Propranolol HCl-loaded pellets were coated in a fluidized bed coater with organic polymer solutions; thin, drug-containing and drug-free, polymeric films were prepared using a casting knife. In vitro drug release, water uptake and dry weight loss studies were performed in 0.1 M HCl and phosphate buffer pH 7.4, respectively. The apparent drug diffusion coefficients within the polymeric systems were determined using different experimental and theoretical techniques (side-by-side diffusion cells, in vitro drug release from thin films; exact and approximate solutions of Fick's second law of diffusion). A broad range of drug release patterns from coated pellets could be achieved by varying the GIT-insoluble:enteric polymer blend ratio. With increasing relative amounts of Eudragit L, the release rates in both media significantly increased. The increase at low pH could be attributed to an increase in water uptake, as observed with thin films. Interestingly, only partial Eudragit L leaching occurred in phosphate buffer pH 7.4 even at high enteric polymer contents, indicating that the GIT-insoluble polymer effectively hindered the dissolution of the entrapped Eudragit L. At high pH, both polymer leaching and polymer swelling contributed to the control of drug release. The determined apparent drug diffusion coefficients take the two effects adequately into account.

  18. Biology Teacher and Expert Opinions about Computer Assisted Biology Instruction Materials: A Software Entitled Nucleic Acids and Protein Synthesis

    ERIC Educational Resources Information Center

    Hasenekoglu, Ismet; Timucin, Melih

    2007-01-01

    The aim of this study is to collect and evaluate opinions of CAI experts and biology teachers about a high school level Computer Assisted Biology Instruction Material presenting computer-made modelling and simulations. It is a case study. A material covering "Nucleic Acids and Protein Synthesis" topic was developed as the…

  19. Changes of insoluble elastin in the rat aorta depending on isolation method.

    PubMed

    Wimmerová, J; Benesová, J; Kosar, K; Ledvina, M

    1989-01-01

    The present paper brings data on quantitative and qualitative changes of insoluble elastin in the rat aorta depending on the used isolation method. In the content of desmosine crosslinks, so as in the accumulation of insoluble elastin in the aorta, considerable differences were found between the results obtained by means of the cyanogen bromide method and those determined in the samples after alkaline hydrolysis. It is underlined by the authors that these methodical differences must be taken into consideration whenever effects of various drugs on the formation of insoluble elastin and on the desmosine crosslinks are examined. Accumulation of insoluble elastin and formation of desmosine crosslinks in the rat aorta were found to be delayed as compared to the chicks. This, unlike the chicks, enables us to influence the formation of desmosine crosslinks in the rat even during the postnatal period.

  20. Analysis of glyphosate and aminomethylphosphonic acid in water, plant materials and soil.

    PubMed

    Koskinen, William C; Marek, LeEtta J; Hall, Kathleen E

    2016-03-01

    There is a need for simple, fast, efficient and sensitive methods of analysis for glyphosate and its degradate aminomethylphosphonic acid (AMPA) in diverse matrices such as water, plant materials and soil to facilitate environmental research needed to address the continuing concerns related to increasing glyphosate use. A variety of water-based solutions have been used to extract the chemicals from different matrices. Many methods require extensive sample preparation, including derivatization and clean-up, prior to analysis by a variety of detection techniques. This review summarizes methods used during the past 15 years for analysis of glyphosate and AMPA in water, plant materials and soil. The simplest methods use aqueous extraction of glyphosate and AMPA from plant materials and soil, no derivatization, solid-phase extraction (SPE) columns for clean-up, guard columns for separation and confirmation of the analytes by mass spectrometry and quantitation using isotope-labeled internal standards. They have levels of detection (LODs) below the regulatory limits in North America. These methods are discussed in more detail in the review.

  1. Critical evaluation of changes in the ratio of insoluble bound to soluble phenolics on antioxidant activity of lentils during germination.

    PubMed

    Yeo, JuDong; Shahidi, Fereidoon

    2015-01-21

    A new indicator, the ratio of insoluble bound phenolics (IBPs) to soluble phenolics (SPs), is suggested as an effective means to monitor changes in the antioxidant activity of lentils during germination. This indicator may be used to monitor other process-induced changes in antioxidant potential of food phenolics in other foods. The antioxidant activity of SPs, IBPs, and total value, the sum of both free and esterified phenolics, of germinated CDC Richlea lentil variety was evaluated for 4 days. Total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging ability were employed to record antioxidant activities. An incremental increase in IBPs was found in TPC, TFC, DPPH, and ABTS radical cation scavenging ability, whereas SPs showed a declining trend in TFC, DPPH, and ABTS, except TPC during 4 days of germination. The ratio of IBPs to SPs increased using most methods, and this may be possibly due to the changes of phenolic compound formation from soluble into insoluble bound form during germination process. The ratio can be used as a novel method for monitoring process-induced changes in the antioxidant activity of foods.

  2. Comparisons of methods to obtain insoluble particles in snow for transmission electron microscopy

    NASA Astrophysics Data System (ADS)

    Ren, Yong; Zhang, Xiongfei; Wei, Hailun; Xu, Liang; Zhang, Jian; Sun, Jiaxing; Wang, Xin; Li, Weijun

    2017-03-01

    Most studies of insoluble particles in snow have been focused on their mass concentration. Little is understood about the physicochemical properties of individual insoluble particles in snow. However, the information is essential to trace sources of the particles, to understand ice nuclei, and to quantify critical aerosol particles (e.g., black carbon) in snow analyzed by bulk methods. The lack of individual particle analyses of snow meltwater stems from the difficulty of producing feasible samples of the snow-borne insoluble particles. In this study, we examined six sample preparation methods and compared their results using transmission electron microscopy (TEM). The results are the following: (1) Drop-by-drop method (DDM) is the easiest method to make TEM samples but cannot remove the influence of the dissolved substances in snow meltwater. (2) Direct filtration method (DFM) was infeasible because the water penetration of carbon film on copper TEM grids is low. (3) Filtration and transfer method (FTM) is through using ultrasonication to transfer insoluble particles on the nuclepore polycarbonate membranes to TEM grids. The drawback of this method is that ultrasonication breaks individual particles into fragments. (4) Freeze-drying method (FDM) can result in new particles from the drying dissolved substances, which interferes with the identification of insoluble particles. (5) Dilution-gravity separation method (DGM) can obtain different substances based on their specific gravity in long standing water. The method can effectively reduce soluble substances but lose insoluble carbonaceous particles (e.g., soot and organic particles). (6) Tangential flow filtration and dilution (TFF-D) through concentrating and desalting dissolved substances is to remove the dissolved substances but keep insoluble particles in snow meltwater. The TFF-D method not only can be suitable for electron microscopy to study individual insoluble particles in snow meltwater but also for any

  3. The existence of an insoluble Z disc scaffold in chicken skeletal muscle.

    PubMed

    Granger, B L; Lazarides, E

    1978-12-01

    Extraction of glycerinated chicken skeletal muscle with 0.6 M potassium iodide leaves a framework of insoluble components within each muscle fiber. This framework is composed primarily of planes of in-register Z discs that have been thickened by the accumulation of material on both sides of each disc during extraction. Membrane vesicles, presumably remnants of the T system, remain surrounding the Z discs. When the framework is sheared in a blender, it is preferentially cleaved between Z planes, resulting in the formation of large sheets of interconnected, closely packed Z discs in a honeycomb-like array. Cleavage occurs in regions formerly occupied by the A bands, which have been weakened by the removal of myosin. The existence and stability of these planar Z disc arrays demonstrate the presence and strength of connections between adjacent myofibrils. SDS-polyacrylamide gel electrophoresis reveals that this framework consists primarily of actin and desmin, with lesser amounts of a few proteins including alpha-actinin, myosin and tropomyosin. Z disc sheets and KI-extracted myofibrils provide a distinct face-on view and side view, respectively, of the Z disc. In indirect immunofluorescence, these two views have revealed that desmin is present at the periphery of each Z disc, forming a network of proteinaceous collars within the Z plane. alpha-Actinin is localized within each disc, giving a face-on fluorescence pattern that is complementary to that of desmin. Actin is present throughout the thickened Z plane, while myosin and tropomyosin exist only in the insoluble residue that coalesces on both faces of each disc. We conclude that desmin, perhaps in conjunction with actin, is responsible for interlinking Z discs of adjacent myofibrils, and may thus serve as a mechanical and structural integrator of muscle fibers. Its hydrophobic nature and coincident distribution with the T system suggest that it may also be responsible for mediating filament-membrane interactions

  4. Improving the controlled release of water-insoluble emodin from amino-functionalized mesoporous silica

    NASA Astrophysics Data System (ADS)

    Xu, Yunqiang; Wang, Chunfeng; Zhou, Guowei; Wu, Yue; Chen, Jing

    2012-06-01

    Several types of amino-functionalized mesoporous silica, including F5-SBA-15, F10-SBA-15, and F15-SBA-15 were prepared through co-condensation of tetraethoxysilane (TEOS) and (3-aminopropyl)triethoxysilane (APTES) in varying molar ratios (5 mol%, 10 mol%, and 15 mol%) via a hydrothermal process. The materials obtained were characterized by means of small-angle X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption, Fourier transformed infrared spectra, and X-ray photoelectron spectroscopy. Increasing APTES molar ratios decreased the degree of orderliness of the functionalized mesoporous silica. Pure and amino-functionalized SBA-15 samples were employed as supports for the controlled release of water-insoluble drug emodin. Loading experiments showed that drug loading capacities mainly depended on the surface areas and pore diameters of the carriers. Controlled release profiles of emodin-loaded samples were studied in phosphate buffered saline (PBS, pH 7.4), and results indicated that the emodin release rate could be controlled by surface amino-functionalized carriers. Emodin loaded on functionalized mesoporous supports exhibited a lower release rate than that of loaded on pure SBA-15, emodin loaded on F10-SBA-15 showed the smallest release amount (71.74 wt%) after stirring in PBS for 60 h. Findings suggest that functionalized mesoporous SBA-15 is a promising carrier for achieving prolonged release time periods.

  5. Effects of insoluble surfactants on the nonlinear dynamics of oscillating liquid bridges

    NASA Astrophysics Data System (ADS)

    Whitaker, John; Ambravaneswaran, Balasubramanian; Basaran, Osman A.

    1998-11-01

    The dynamics of oscillating liquid bridges is of importance in applications including drop and jet breakup, measurement of physical properties of high temperature materials, and agglomeration of powders. Although the stability of static bridges and the dynamics of oscillating and stretching bridges of pure liquids have been extensively studied, even a rudimentary understanding of the dynamics of oscillating bridges of surfactant-laden liquids is lacking. In this work, the dynamics of a bridge of a Newtonian liquid containing an insoluble surfactant are analyzed by solving numerically the complete free boundary problem comprised of the transient Navier-Stokes system that governs fluid flow and the convection-diffusion equation that governs surfactant transport. The dynamical response of oscillating bridges are determined here by performing both a frequency response analysis (FRA) and a sweep procedure in which either the forcing frequency or forcing amplitude is first increased and then decreased over a range. Results of FRA reveal how unintended contaminants present on the fluid interface can alter property measurements made with the oscillating bridge technique. Furthermore, it is shown that the relative importance of surfactant convection to surfactant diffusion plays a complex role in setting the dynamic response of oscillating liquid bridges and their resonance frequencies.

  6. Determination of the Insoluble Aluminum Content in Steel Samples by Using Laser-Induced Breakdown Spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Jia, Yunhai; Zhang, Yong; Sun, Nian

    2015-08-01

    The insoluble aluminum content in steel samples has a significant influence on the quality of the steel. In this paper, laser-induced breakdown spectroscopy (LIBS) is used to analyze the insoluble aluminum content in steel samples using a scanning mode. The average intensity plus 2.5 standard deviations was iterated and the final iteration value was taken as the threshold that distinguishes soluble and insoluble aluminum, and thus total and soluble aluminum content calibration curves were generated. Using the relevant total and soluble aluminum content calibration curves, the total and soluble aluminum contents in steel samples could be determined. The insoluble aluminum content could be determined by subtracting the soluble aluminum content from the total aluminum content. The insoluble aluminum content of standard samples and process product samples were determined using the present mathematical model; the results agreed well with the certified reference values. This method could be used to rapidly characterize the insoluble aluminum content in steel samples. supported by National Key Scientific Instrument and Equipment Development Project, China (No. 2012YQ20018208)

  7. Dilute sulfuric acid pretreatment of sunflower stalks for sugar production.

    PubMed

    Ruiz, Encarnación; Romero, Inmaculada; Moya, Manuel; Cara, Cristóbal; Vidal, Juan D; Castro, Eulogio

    2013-07-01

    In this work the pretreatment of sunflower stalks by dilute sulfuric acid is studied. Pretreatment temperature and the concentration of acid solution were selected as operation variables and modified according to a central rotatable composite experimental design. Based on previous studies pretreatment time was kept constant (5 min) while the variation range for temperature and acid concentration was centered at 175°C and 1.25% (w/v) respectively. Following pretreatment the insoluble solids were separated by filtration and further submitted to enzymatic hydrolysis, while liquid fractions were analyzed for sugars and inhibitors. Response surface methodology was applied to analyze results based on the combined severity of pretreatment experiments. Optimized results show that up to 33 g of glucose and xylose per 100g raw material (65% of the glucose and xylose present in the raw material) may be available for fermentation after pretreatment at 167°C and 1.3% sulfuric acid concentration.

  8. Influence of fatty acid composition of raw materials on biodiesel properties.

    PubMed

    Ramos, María Jesús; Fernández, Carmen María; Casas, Abraham; Rodríguez, Lourdes; Pérez, Angel

    2009-01-01

    The aim of this work was the study of the influence of the raw material composition on biodiesel quality, using a transesterification reaction. Thus, ten refined vegetable oils were transesterificated using potassium methoxide as catalyst and standard reaction conditions (reaction time, 1h; weight of catalyst, 1 wt.% of initial oil weight; molar ratio methanol/oil, 6/1; reaction temperature, 60 degrees C). Biodiesel quality was tested according to the standard [UNE-EN 14214, 2003. Automotive fuels. Fatty acid methyl esters (FAME) for diesel engines. Requirements and test methods]. Some critical parameters like oxidation stability, cetane number, iodine value and cold filter plugging point were correlated with the methyl ester composition of each biodiesel, according to two parameters: degree of unsaturation and long chain saturated factor. Finally, a triangular graph based on the composition in monounsaturated, polyunsaturated and saturated methyl esters was built in order to predict the critical parameters of European standard for whatever biodiesel, known its composition.

  9. A new supporting material for fascia grafting during myringoplasty: polyglycolic acid sheets.

    PubMed

    Yamanaka, Toshiaki; Sawai, Yachiyo; Hosoi, Hiroshi

    2013-08-01

    We used polyglycolic acid (PGA) sheets, a reinforcing material, as supporting devices for securing the fascia instead of fibrin glue or Gelfoam in patients with tympanic membrane (TM) perforations. PGA sheets were placed lateral to the fascia graft attached using the underlay grafting technique in 6 patients. In each case, the PGA sheet had been macerated and had merged into the fascia within 1 week of the procedure. At 2 to 3 postoperative weeks, parts of the sheet had become dehydrated and detached from the fascia, revealing a new epithelialized TM underneath. Eventually, the sheet had disappeared, and complete epithelialization had been achieved at 4 to 5 postoperative weeks, resulting in the successful closure of the perforation. The repair of TM remained stable throughout the follow-up period of at least 6 months in all patients. These results suggest that PGA sheets have the potential to secure fascia grafts and to guide the epithelialization of new tissue.

  10. Self-assembly into soft materials of molecules derived from naturallyoccurring fatty-acids

    NASA Astrophysics Data System (ADS)

    Zhang, Mohan

    The self-assembly of molecular gelators has provided an attractive route for the construction of nanostructured materials with desired functionalities. A well-defined paradigm for the design of molecular gels is needed, but none has yet been established. One of the important challenges to defining this paradigm is the creation of structure-property correlations for gelators at different distance scales. This dissertation centers on gaining additional insights in the relationship between small changes in gelator structures derived from long-chain, naturally-occurring fatty acids and the properties of the corresponding gels. This approach offers a reasonable method to probe the rational design of molecular gelators. (Abstract shortened by ProQuest.).

  11. Synthesis and characterization of polymeric materials derived from 2,5-diketopiperazines and pyroglutamic acid

    NASA Astrophysics Data System (ADS)

    Parrish, Dennis Arch

    The research presented in this dissertation describes the investigation of 2,5-diketopiperazines (DKPs) as property modifiers for addition polymers and the self association behavior of pyroglutamic acid derivatives. The first project involved the copolymerization of methyl methacrylate and styrene with DKP-based methacrylate monomers. Low incorporations of serine- and aspartame-based DKPs in the copolymer resulted in dramatic increases in the glass transition temperature (Ts). The research presented in Chapter II focuses on the ring-opening reactions of pyroglutamic diketopiperazine (pyDKP). The original intent was to synthesize polymers containing backbone DKPs through ring-opening polymerization of the five-membered rings. However, it was discovered that regioselective ring-opening occurs at the six-membered ring to give pyroglutamic acid derivatives. Since this reaction had not been reported previously, the focus of research was altered to investigate the scope and limitations of the new reaction. The ring-opening reactions of pyDKP with diamines to give bispyroglutamides is described in Chapter IV. While these materials are not polymeric, they display polymeric behavior. It was found that multi-functional pyroglutamides display Tgs during thermal analysis, exhibit high thermal stability, and form melt-drawn fibers. In contrast, the materials have low solution viscosities and are freely soluble in water, ethanol, and chloroform. This behavior is attributed to non-covalent supramolecular associations. The final part of this dissertation involved the investigation of thermoreversible organic solvent gelators. The ring-opening reaction of pyDKP with long alkyl amines unexpectedly gelled the reaction solvent. A series of analogous gelators were synthesized, and the minimum concentration required for gelation in various solvents was determined. It was found that the nature of the solvent, alkyl chain length, and optical activity of the gelator determined gelator

  12. Characterization and Acid-Mobilization Study of Iron-Containing Mineral Dust Source Materials

    SciTech Connect

    Cwiertny, David M.; Baltrusaitis, Jonas; Hunter, Gordon J.; Laskin, Alexander; Scherer, Michelle; Grassian, Vicki H.

    2008-03-04

    Processes that solubilize the iron in mineral dust aerosols may increase the amount of iron supplied to ocean surface waters, and thereby stimulate phytoplankton productivity. It was recently proposed that mixing of mineral dusts with SO2 and HNO3 produces extremely acidic environments that favor the formation of bioavailable Fe(II). Here, four authentic mineral dust source materials (Saudi Beach sand (SB), Inland Saudi sand (IS), Saharan Sand (SS) and China Loess (CL)) and one commercial reference material (Arizona Test Dust (AZTD)) were spectroscopically characterized, and their dissolution at pH 1 was examined in aqueous batch systems. Spectroscopic analyses indicated that the bulk and near-surface region of all samples possessed similar elemental compositions and that iron was unevenly distributed among dust 10 particles. Mössbauer spectroscopy revealed Fe(III) in all samples, although SB, CL and AZTD also contained appreciable Fe(II). Both Fe(II) and Fe(III) were primarily substituted into aluminosilicates, although CL, AZTD and IS also contained Fe(III) oxides. Total iron solubility (defined as the summed concentration of dissolved Fe(II) and Fe(III) measured after 24 h) ranged 14 between 4-12% of the source materials’ iron content, but did not scale with either the surface area or the iron content of the samples. This suggests that other factors such as iron speciation and mineralogy may play a key role in iron solubility. Also, the elevated nitrate concentrations encountered from nitric acid at pH 1 suppressed dissolution of Fe(II) from AZTD, CL and SB particles, which we propose results from the surface-mediated, non-photochemical reduction of nitrate by Fe(II).

  13. Why do proteins aggregate? “Intrinsically insoluble proteins” and “dark mediators” revealed by studies on “insoluble proteins” solubilized in pure water

    PubMed Central

    Song, Jianxing

    2013-01-01

    In 2008, I reviewed and proposed a model for our discovery in 2005 that unrefoldable and insoluble proteins could in fact be solubilized in unsalted water. Since then, this discovery has offered us and other groups a powerful tool to characterize insoluble proteins, and we have further addressed several fundamental and disease-relevant issues associated with this discovery. Here I review these results, which are conceptualized into several novel scenarios. 1) Unlike 'misfolded proteins', which still retain the capacity to fold into well-defined structures but are misled to 'off-pathway' aggregation, unrefoldable and insoluble proteins completely lack this ability and will unavoidably aggregate in vivo with ~150 mM ions, thus designated as 'intrinsically insoluble proteins (IIPs)' here. IIPs may largely account for the 'wastefully synthesized' DRiPs identified in human cells. 2) The fact that IIPs including membrane proteins are all soluble in unsalted water, but get aggregated upon being exposed to ions, logically suggests that ions existing in the background play a central role in mediating protein aggregation, thus acting as 'dark mediators'. Our study with 14 salts confirms that IIPs lack the capacity to fold into any well-defined structures. We uncover that salts modulate protein dynamics and anions bind proteins with high selectivity and affinity, which is surprisingly masked by pre-existing ions. Accordingly, I modified my previous model. 3) Insoluble proteins interact with lipids to different degrees. Remarkably, an ALS-causing P56S mutation transforms the β-sandwich MSP domain into a helical integral membrane protein. Consequently, the number of membrane-interacting proteins might be much larger than currently recognized. To attack biological membranes may represent a common mechanism by which aggregated proteins initiate human diseases. 4) Our discovery also implies a solution to the 'chicken-and-egg paradox' for the origin of primitive membranes embedded

  14. Peptide interfacial biomaterials improve endothelial cell adhesion and spreading on synthetic polyglycolic acid materials.

    PubMed

    Huang, Xin; Zauscher, Stefan; Klitzman, Bruce; Truskey, George A; Reichert, William M; Kenan, Daniel J; Grinstaff, Mark W

    2010-06-01

    Resorbable scaffolds such as polyglycolic acid (PGA) are employed in a number of clinical and tissue engineering applications owing to their desirable property of allowing remodeling to form native tissue over time. However, native PGA does not promote endothelial cell adhesion. Here we describe a novel treatment with hetero-bifunctional peptide linkers, termed "interfacial biomaterials" (IFBMs), which are used to alter the surface of PGA to provide appropriate biological cues. IFBMs couple an affinity peptide for the material with a biologically active peptide that promotes desired cellular responses. One such PGA affinity peptide was coupled to the integrin binding domain, Arg-Gly-Asp (RGD), to build a chemically synthesized bimodular 27 amino acid peptide that mediated interactions between PGA and integrin receptors on endothelial cells. Quartz crystal microbalance with dissipation monitoring (QCMD) was used to determine the association constant (K (A) 1 x 10(7) M(-1)) and surface thickness (~3.5 nm). Cell binding studies indicated that IFBM efficiently mediated adhesion, spreading, and cytoskeletal organization of endothelial cells on PGA in an integrin-dependent manner. We show that the IFBM peptide promotes a 200% increase in endothelial cell binding to PGA as well as 70-120% increase in cell spreading from 30 to 60 minutes after plating.

  15. Enhanced biocompatibility and antibacterial property of polyurethane materials modified with citric acid and chitosan.

    PubMed

    Liu, Tian-Ming; Wu, Xing-Ze; Qiu, Yun-Ren

    2016-08-01

    Citric acid (CA) and chitosan (CS) were covalently immobilized on polyurethane (PU) materials to improve the biocompatibility and antibacterial property. The polyurethane pre-polymer with isocyanate group was synthesized by one pot method, and then grafted with citric acid, followed by blending with polyethersulfone (PES) to prepare the blend membrane by phase-inversion method so that chitosan can be grafted from the membrane via esterification and acylation reactions eventually. The native and modified membranes were characterized by attenuated total reflectance-Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy, scanning electron microscopy, water contact angle measurement, and tensile strength test. Protein adsorption, platelet adhesion, hemolysis assay, activated partial thromboplastin time, prothrombin time, thrombin time, and adsorption of Ca(2+) were executed to evaluate the blood compatibility of the membranes decorated by CA and CS. Particularly, the antibacterial activities on the modified membranes were evaluated based on a vitro antibacterial test. It could be concluded that the modified membrane had good anticoagulant property and antibacterial property.

  16. Rehabilitating acid soils for increasing crop productivity through low-cost liming material.

    PubMed

    Bhat, Javid Ahmad; Kundu, Manik Chandra; Hazra, Gora Chand; Santra, Gour Hari; Mandal, Biswapati

    2010-09-15

    Productivity of red and lateritic soils is low because of their acidity and deficiencies in few essential nutrients viz., nitrogen, phosphorus, calcium, zinc, boron, molybdenum etc. We compared the effectiveness of basic slag, a low-cost liming material, with that of calcite as an ameliorant for these soils using mustard followed by rice as test crops. Experiments were conducted with three levels of each of basic slag and calcite along with a control on farmers' fields at 14 different locations. Influence of farmyard manure (FYM) and poultry manure (PM) on the effectiveness of the slag was also tested. On an average, basic slag performed better than calcite in increasing yields of both mustard and rice and left over higher amounts of available Ca, Si and Zn in residual soils. The slag also improved N, P, K and Ca nutrition of mustard and Si and Zn nutrition of rice with a favorable benefit:cost (B:C) ratio over the calcite (4.82 vs. 1.44). Effectiveness of the basic slag improved when it was applied in combination with FYM or PM (B:C, 5.83 and 6.27). Basic slag can, therefore, be advocated for use in the acidic red and lateritic soils for economically improving their productivity.

  17. Small intestinal goblet cell proliferation induced by ingestion of soluble and insoluble dietary fiber is characterized by an increase in sialylated mucins in rats.

    PubMed

    Hino, Shingo; Takemura, Naoki; Sonoyama, Kei; Morita, Akio; Kawagishi, Hirokazu; Aoe, Seiichiro; Morita, Tatsuya

    2012-08-01

    The study aimed to examine the effects of insoluble and soluble fibers on mucin sialylation and sulfation in the small intestine. First, diets containing soluble [konjac mannan (KM), psyllium, or guar gum; 50 g/kg) or insoluble (polystyrene foam, wheat bran, or cornhusk; 80 g/kg) fiber were fed to rats for 13 d. The fiber-fed groups had more goblet cells in the ileum than the fiber-free control group. High-iron diamine/alcian blue staining showed more sialylated mucin-producing cells in the fiber-fed groups than in the control, whereas sulfated mucin-producing cells were fewer (insoluble fibers) or unchanged (soluble fibers). Second, feeding KM (50 g/kg) and beet fiber (BF) (80 g/kg) diets for 7 d yielded a higher ileum Siat4C expression than the control, but Gal3ST2 and Gal3ST4 expression was comparable. Luminal mucin content correlated with sialic acid (r = 0.96; P < 0.001) or sulfate (r = 0.62; P < 0.01), but the slope of the sialic acid-derived equation was greater than that of the sulfate-derived equation, indicating a preferred increase in sialylated mucins. Third, rats were fed the control diet for 10 d while receiving antibiotic treatment. Analysis of the luminal mucin showed that sialylated mucins were more vulnerable to bacterial degradation than sulfated mucins. Finally, a study of bromo-deoxyuridine incorporation in rats fed a BF diet indicated that goblet cell proliferation accompanied by increased sialylated mucin appeared to be related to accelerated ileal epithelial cell migration. We conclude that intestinal goblet cell responses to insoluble and soluble fibers are characterized by increases in sialylated mucin production.

  18. Effects of sulfation on the physicochemical and functional properties of a water-insoluble polysaccharide preparation from Ganoderma lucidum.

    PubMed

    Liu, Wei; Wang, Hengyu; Yao, Wenbing; Gao, Xiangdong; Yu, Liangli Lucy

    2010-03-24

    The sulfation of a water-insoluble Ganoderma lucidum polysaccharide (GLP) was successfully carried out with chlorosulfonic acid-pyridine in dimethyl formamide to prepare three sulfated GLP derivatives, named sGLP1, sGLP2, and sGLP3. The chemical structure of the sulfated GLP was confirmed by Fourier transform infrared and (13)C NMR analyses. The sGLPs were evaluated for their water solubility, degree of substitution (DS), antioxidant properties, and bile acid-binding capacities. The results showed that sulfation improved the water solubility of GLP and increased its scavenging capacities against hydroxyl and superoxide anion radicals, hydrogen peroxide-scavenging activity, Fe(II) chelating ability, reducing power, and bile acid-binding capacities. It was also observed that the DS may influence the physicochemical and functional properties of sGLPs. For instance, the sulfated GLP with the lowest DS had the greatest bile acid-binding capacity, and the sGLP that had the highest DS showed the lowest bile acid-binding ability under the experimental conditions. The results from this study suggested that sulfation is a possible approach to obtain novel water-soluble derivatives of GLP with improved physicochemical, functional, and biological properties for potential utilization in functional foods or supplemental products.

  19. Biocompatibility of poly(lactic acid) with incorporated graphene-based materials.

    PubMed

    Pinto, Artur M; Moreira, Susana; Gonçalves, Inês C; Gama, Francisco M; Mendes, Adélio M; Magalhães, Fernão D

    2013-04-01

    The incorporation of graphene-based materials has been shown to improve mechanical properties of poly(lactic acid) (PLA). In this work, PLA films and composite PLA films incorporating two graphene-based materials - graphene oxide (GO) and graphene nanoplatelets (GNP) - were prepared and characterized regarding not only biocompatibility, but also surface topography, chemistry and wettability. The presence of both fillers changed the films surface topography, increasing the roughness, and modified the wettability - the polar component of surface free energy increased 59% with GO and decreased 56% with GNP. Mouse embryo fibroblasts incubated with both fillers exceeded the IC(50) in both cases with a concentration of 10 μg mL(-1). No variations in cell proliferation at the surface of the composite films were observed, except for those containing GO after 24 h incubation, which presented higher cell proliferation than pristine PLA films. Platelet adhesion to PLA and PLA/GNP films was lower in the presence of plasma proteins than when no proteins were present. Furthermore, incorporation of GNP into PLA reduced platelet activation in the presence of plasma proteins. The results indicated that low concentrations of GO and GNP may be incorporated safely in PLA to improve aspects relevant for biomedical applications, such as mechanical properties.

  20. Rheological characterization of hyaluronic acid derivatives as injectable materials toward nucleus pulposus regeneration.

    PubMed

    Gloria, Antonio; Borzacchiello, Assunta; Causa, Filippo; Ambrosio, Luigi

    2012-02-01

    Nucleus pulposus (NP) is the soft center of the intervertebral disc (IVD), able to resist compressive loads, while the annulus fibrosus withstands tension and gives mechanical strength. NP function may be altered as consequence of several pathologies or injury and when a damaged IVD does not properly play its role. In the past years, a great effort has been devoted to the design of injectable systems as NP substitutes. The different synthetic- and natural hydrogel-based materials proposed, present many drawbacks and, in particular, they do not seem to mimic the required behavior. In the search for natural-based systems a dodecylamide of hyaluronic acid (HA), HYADD3®, has been proved as bioactive and suitable vehicle to carry cells for NP tissue engineering, while a crosslinked HA ester, HYAFF120® showed interesting results if used as injectable acellular material. Even though these derivatives showed appropriate biological behavior up to now, data on mechanical behavior of these derivatives are still missing. In this frame, the aim of this study was to provide a rheological characterization of these HA derivatives to asses their biomechanical compatibility with the NP tissue. To this, the rheological properties of these derivatives were studied through dynamic shear tests before and after injection through needles used in the current surgical procedure. Both HA derivatives showed a 'gel-like' rheological behavior similar to the native NP tissue and this behavior was not altered by injection.

  1. Silylated melamine and cyanuric acid as precursors for imprinted and hybrid silica materials with molecular recognition properties.

    PubMed

    Arrachart, Guilhem; Carcel, Carole; Trens, Philippe; Moreau, Jöel J E; Wong Chi Man, Michel

    2009-06-15

    Two monotrialkoxysilylated compounds that consist of complementary fragments of melamine (M) and cyanuric acid (CA) have been synthesised. The molecular recognition properties of the M and CA fragments through complementary hydrogen bonds (DAD and ADA; D=donor, A=acceptor) are the key factor used to direct the formation of hybrid silica materials by using a sol-gel process. These materials were synthesised following two methods: First, an organo-bridged silsesquioxane was obtained by the hydrolysis of the two complementary monotrialkoxysilylated melamine and cyanuric acid derivatives, with fluoride ions as a catalyst. The hydrogen-bonding interactions between the two organic fragments are responsible for the formation of the bridging unit. The transcription of the assembly into the hybrid material was characterised and evidenced by solid-state NMR (29Si, 13C) and FTIR spectroscopic experiments. Second, the molecular recognition was exploited to synthesise an imprinted hybrid silica. This material was prepared by co-condensation of tetraethyl orthosilicate (TEOS) with the monosilylated cyanuric acid derivative (CA) templated by nonsilylated melamine. The melamine template was completely removed by treating the solid material with hydrochloric acid. The reintroduction of the template was performed by treating the resulting material with an aqueous suspension of melamine. These steps were monitored and analysed by several techniques, such as solid-state NMR (29Si, 13C) and FTIR spectroscopic analysis and nitrogen adsorption-desorption isotherms.

  2. Molecular glass positive i-line photoresist materials containing 2,1,4-DNQ and acid labile group

    NASA Astrophysics Data System (ADS)

    Wang, Liyuan; Yu, Jinxing; Xu, Na

    2010-04-01

    Recent years increasing attention has been given to molecular glass resist materials. In this paper, maleopimaric acid, cycloaddition reaction product of rosin with maleic anhydride, was reacted with hydroxylamine and then further esterified with 2-diazo-1-naphthoquinone-4-sulfonyl chloride to give N-hydroxy maleopimarimide sulfonate. The carboxylic acid group of the compound was then protected by the reaction of this compound with vinyl ethyl ether or dihydropyran. Thus obtained compounds were amorphous. When irradiated with i-line light, the 2,1,4-DNQ group undergo photolysis not only to give off nitrogen gas but also generate sulfonic acid which can result in the decomposition of the acid labile group. So, a novel chemically amplified positive i-line molecular glass photoresists can be formed by the compound and other acidolytic molecular glass compounds. The lithographic performance of the resist materials is evaluated.

  3. Studies of Diesel Fuel Insolubles Formation and Fuel Stabilizer Additives

    DTIC Science & Technology

    1988-08-01

    gel 1-Octadecene 98.6% min Indole 99+%6 * -. ,2-Methyl Indole 98% Benzoic Acid Primary Standard p- Phenylphenol 99+%6 Quinoline Reagent Grade I-Butanol...each sample. Analysis of the precipitate showed that it was p- phenylphenol . During the preparation of the MS-1 samples, difficulty was experienced in...getting the p- phenylphenol to fully dissolve. Also GC/MS analysis of the sediments formed by MS-I showed only the starting reagents. For these reasons

  4. Carbon Materials Research

    DTIC Science & Technology

    2005-07-14

    behavior, interfacial energies, and surface molecular orientation (surface anchoring states) for mesophase pitch on carbon fibers and other...Mochida (2) extended it to the production of mesophase pitch by dramatically raising Distribution A: Approved for public release; distribution...involved i.e. it is a very insoluble material. Mochida, however, recognized that this material was liquid-crystalline mesophase pitch , which was

  5. Physicochemical and Functional Properties of Insoluble Dietary Fiber Isolated from Bambara Groundnut (Vigna subterranea [L.] Verdc.).

    PubMed

    Diedericks, Claudine F; Jideani, Victoria A

    2015-09-01

    Bambara groundnut (BGN) is a widely cultivated legume with a rich nutritional profile, yet despite its many benefits it still remains underutilized. To highlight its potential value, 4 BGN varieties-brown, red, black eye, and brown eye were subjected to sequential enzymatic treatments followed by centrifugation to obtain the insoluble dietary fiber (IDF) fraction. The IDFs were vacuum-dried and evaluated for color, hydration properties, fat absorption, polyphenolic compounds, neutral sugars, and uronic acids. An optimized white bread formulation was also determined using brown BGN-IDF in an optimal (IV) mixture design. Three mixture components constrained at lower and upper limits (water: 57% to 60%, yeast: 2.3% to 5.3%, and BGN-IDF: 7% to 10%) were evaluated for their effects on responses of specific loaf volume, gumminess, chewiness, and resilience of the loaves. All BGN-IDFs differed significantly (P ≤ 0.05) across all color parameters. Polyphenols were significantly (P ≤ 0.05) highest in red and brown BGN-IDFs. Arabinose/galactose (31.04% to 37.12%), xylose (16.53% to 27.30%), and mannose (14.48% to 22.24%) were the major sugars identified. Swelling capacity was significantly (P ≤ 0.05) highest for brown eye BGN-IDF (7.72 ± 0.49 mL/g). Water retention capacity ranged from 1.63 to 2.01 g water/g dry weight. Fat absorption for red BGN-IDF differed significantly (P ≤ 0.05). Furthermore, the best optimal white bread formulation enriched with brown BGN-IDF was established with numerical optimization at 59.5% water, 4.3% yeast, and 8.5% BGN-IDF. Overall positive physicochemical and functional properties were observed for BGN-IDFs, and it was shown that an optimal white bread enriched with BGN-IDF could be produced.

  6. Effects of material thickness and processing method on poly(lactic-co-glycolic acid) degradation and mechanical performance.

    PubMed

    Shirazi, Reyhaneh Neghabat; Aldabbagh, Fawaz; Ronan, William; Erxleben, Andrea; Rochev, Yury; McHugh, Peter

    2016-10-01

    In this study, the effects of material thickness and processing method on the degradation rate and the changes in the mechanical properties of poly(lactic-co-glycolic acid) material during simulated physiological degradation were investigated. Two types of poly(lactic-co-glycolic acid) materials were considered: 0.12 mm solvent-cast films and 1 mm compression-moulded plates. The experimental results presented in this study were compared to the experimental results of Shirazi et al. (Acta Biomaterialia 10(11):4695-703, 2014) for 0.25 mm solvent-cast films. These experimental observations were used to validate the computational modelling predictions of Shirazi et al. (J Mech Behav Biomed Mater 54: 48-59, 2016) on critical diffusion length scale and also to refine the model parameters. The specific material processing methods considered here did not have a significant effect on the degradation rate and the changes in mechanical properties during degradation; however, they influenced the initial molecular weight and they determined the stiffness and hardness of the poly(lactic-co-glycolic acid) material. The experimental observations strongly supported the computational modelling predictions that showed no significant difference in the degradation rate and the changes in the elastic modulus of poly(lactic-co-glycolic acid) films for thicknesses larger than 100 μm.

  7. Labeled Indole-Macromolecular Conjugates from Growing Stems Supplied with Labeled Indoleacetic Acid 1

    PubMed Central

    Davies, P. J.; Galston, A. W.

    1971-01-01

    Pea (Pisum sativum var. Alaska) and bean (Phaseolus vulgaris var. Red Kidney) stem sections treated with indoleacetic acid-1-14C, indoleacetic acid-2-14C, and indoleacetic acid-5-3H were homogenized, extracted with phenol, and the water-soluble, ethanol-insoluble material subjected to further fractionation. Following an 18-hour incubation period in indoleacetic acid-1-14C, most of the label was found as nonindole-14C in high molecular weight polysaccharide, as phenol extraction is specific for both RNA and polysaccharides. With indoleacetic acid-2-14C and -5-3H, and to a lesser extent with indoleacetic acid-1-14C, radioactive indoles were obtained by hydrolysis from a heterogeneous fraction between about 500 and 30,000 molecular weight, possibly polysaccharide in nature. Indoleacetic acid accounted for 8% and indole aldehyde accounted for 21% of the total radioactivity in the extract. PMID:16657637

  8. Production and cytotoxicity of extracellular insoluble and droplets of soluble melanin by Streptomyces lusitanus DMZ-3.

    PubMed

    Madhusudhan, D N; Mazhari, Bi Bi Zainab; Dastager, Syed G; Agsar, Dayanand

    2014-01-01

    A Streptomyces lusitanus DMZ-3 strain with potential to synthesize both insoluble and soluble melanins was detected. Melanins are quite distinguished based on their solubility for varied biotechnological applications. The present investigation reveals the enhanced production of insoluble and soluble melanins in tyrosine medium by a single culture. Streptomyces lusitanus DMZ-3 was characterized by 16S rRNA gene analysis. An enhanced production of 5.29 g/L insoluble melanin was achieved in a submerged bioprocess following response surface methodology. Combined interactive effect of temperature (50°C), pH (8.5), tyrosine (2.0 g/L), and beef extract (0.5 g/L) were found to be critical variables for enhanced production in central composite design analysis. An optimized indigenous slant culture system was an innovative approach for the successful production (264 mg/L) of pure soluble melanin from the droplets formed on the surface of the culture. Both insoluble and soluble melanins were confirmed and characterized by Chemical, reactions, UV, FTIR, and TLC analysis. First time, cytotoxic study of melanin using brine shrimps was reported. Maximum cytotoxic activity of soluble melanin was Lc50-0.40 µg/mL and insoluble melanin was Lc50-0.80 µg/mL.

  9. Suitability of polymer materials for production of pulmonary microparticles using a PGSS supercritical fluid technique: thermodynamic behaviour of fatty acids, PEGs and PEG-fatty acids.

    PubMed

    Vijayaraghavan, Meera; Stolnik, Snjezana; Howdle, Steven M; Illum, Lisbeth

    2012-11-15

    The thermodynamic behaviour of selected polymeric components for preparation of controlled release microparticles using supercritical carbon dioxide (scCO(2)) processing was investigated. The polymeric materials selected were egg lecithin (a model for the lung surfactant phospholipid), poly(ethyleneglycol) (PEG) of different molecular weights, fatty acids (C18, C16, and C14), and physical blends of PEGs and fatty acids. In addition a range of PEG-stearates was also assessed. Analysis of thermodynamic behaviour was performed by differential scanning calorimetry (DSC) and by assessment of their interaction with scCO(2) in a high-pressure variable volume view cell. The key criterion was to demonstrate a strong interaction with scCO(2) and to show liquefaction of the polymeric material at acceptable processing temperatures and pressures. Positive results should then indicate the suitability of these materials for processing by the Particle from Gas Saturated Solutions (PGSS) technique using scCO(2) to create microparticles for pulmonary administration. It was found that the materials tested interacted with scCO(2) and showed a sufficient lowering of their melting temperature (T(m)) to make them suitable for use in the PGSS microparticle production rig. Fatty acids of low T(m) were shown to act as a plasticising agent and to lower the T(m) of PEG further during interaction with scCO(2).

  10. Timolol maleate release from hyaluronic acid-containing model silicone hydrogel contact lens materials.

    PubMed

    Korogiannaki, Myrto; Guidi, Giuliano; Jones, Lyndon; Sheardown, Heather

    2015-09-01

    This study was designed to assess the impact of a releasable wetting agent, such as hyaluronic acid (HA), on the release profile of timolol maleate (TM) from model silicone hydrogel contact lens materials. Polyvinylpyrrolidone (PVP) was used as an alternative wetting agent for comparison. The model lenses consisted of a hydrophilic monomer, either 2-hydroxyethyl methacrylate or N,N-dimethylacrylamide and a hydrophobic silicone monomer of methacryloxypropyltris (trimethylsiloxy) silane. The loading of the wetting and the therapeutic agent occurred during the synthesis of the silicone hydrogels through the method of direct entrapment. The developed materials were characterized by minimal changes in the water uptake, while lower molecular weight of HA improved their surface wettability. The transparency of the examined silicone hydrogels was found to be affected by the miscibility of the wetting agent in the prepolymer mixture as well as the composition of the developed silicone hydrogels. Sustained release of TM from 4 to 14 days was observed, with the drug transport occurring presumably through the hydrophilic domains of the silicone hydrogels. The release profile was strongly dependent on the hydrophilic monomer composition, the distribution of hydrophobic (silane) domains, and the affinity of the therapeutic agent for the silicone hydrogel matrix. Noncovalent entrapment of the wetting agent did not change the in vitro release duration and kinetics of TM, however the drug release profile was found to be controlled by the simultaneous release of TM and HA or PVP. In the case of HA, depending on the HA:drug ratio, the release rate was decreased and controlled by the release of HA, likely due to electrostatic interactions between protonated TM and anionic HA. Overall, partitioning of the drug within the hydrophilic domains of the silicone hydrogels as well as interactions with the wetting agent determined the drug release profile.

  11. Lactic acid fermentation by cells immobilised on various porous cellulosic materials and their alginate/poly-lactic acid composites.

    PubMed

    Kumar, Mrinal Nishant; Gialleli, Angelika-Ioanna; Masson, Jean Bernard; Kandylis, Panagiotis; Bekatorou, Argyro; Koutinas, Athanasios A; Kanellaki, Maria

    2014-08-01

    Porous delignified cellulose (or tubular cellulose, abbr. TC) from Indian Mango (Mangifera indica) and Sal (Shorea robusta) wood and Rice husk, and TC/Ca-alginate/polylactic acid composites, were used as Lactobacillus bulgaricus immobilisation carriers leading to improvements in lactic acid fermentation of cheese whey and synthetic lactose media, compared to free cells. Specifically, shorter fermentation rates, higher lactic acid yields (g/g sugar utilised) and productivities (g/Ld), and higher amounts of volatile by-products were achieved, while no significant differences were observed on the performance of the different immobilised biocatalysts. The proposed biocatalysts are of food grade purity, cheap and easy to prepare, and they are attractive for bioprocess development based on immobilised cells. Such composite biocatalysts may be used for the co-immobilisation of different microorganisms or enzymes (in separate layers of the biocatalyst), to efficiently conduct different types of fermentations in the same bioreactor, avoiding inhibition problems of chemical or biological (competition) nature.

  12. Ingestion of insoluble dietary fibre increased zinc and iron absorption and restored growth rate and zinc absorption suppressed by dietary phytate in rats.

    PubMed

    Hayashi, K; Hara, H; Asvarujanon, P; Aoyama, Y; Luangpituksa, P

    2001-10-01

    We examined the effects of ingestion of five types of insoluble fibre on growth and Zn absorption in rats fed a marginally Zn-deficient diet (6.75 mg (0.103 mmol) Zn/kg diet) with or without added sodium phytate (12.6 mmol/kg diet). The types of insoluble fibre tested were corn husks, watermelon skin, yam-bean root (Pachyrhizus erosus) and pineapple core, and cellulose was used as a control (100 g/kg diet). Body-weight gain in the cellulose groups was suppressed by 57 % by feeding phytate. Body-weight gain in phytate-fed rats was 80 % greater in the watermelon skin fibre and yam-bean root fibre group than that in the cellulose group. Zn absorption ratio in the cellulose groups was lowered by 46 and 70 % in the first (days 7-10) and second (days 16-19) measurement periods with feeding phytate. In the rats fed the phytate-containing diets, Zn absorption ratio in the watermelon skin, yam-bean root and pineapple core fibre groups was 140, 80 and 54 % higher respectively than that in the cellulose group, in the second period. Fe absorption was not suppressed by phytate, however, feeding of these three types of fibre promoted Fe absorption in rats fed phytate-free diets. The concentration of soluble Zn in the caecal contents in the watermelon skin fibre or yam-bean root fibre groups was identical to that in the control group in spite of a higher short-chain fatty acid concentration and lower pH in the caecum. These findings indicate that ingestion of these types of insoluble fibre recovered the growth and Zn absorption suppressed by feeding a high level of phytate, and factors other than caecal fermentation may also be involved in this effect of insoluble fibre.

  13. A mortality study of workers exposed to insoluble forms of beryllium

    PubMed Central

    Boffetta, Paolo; Fordyce, Tiffani

    2014-01-01

    This study investigated lung cancer and other diseases related to insoluble beryllium compounds. A cohort of 4950 workers from four US insoluble beryllium manufacturing facilities were followed through 2009. Expected deaths were calculated using local and national rates. On the basis of local rates, all-cause mortality was significantly reduced. Mortality from lung cancer (standardized mortality ratio 96.0; 95% confidence interval 80.0, 114.3) and from nonmalignant respiratory diseases was also reduced. There were no significant trends for either cause of death according to duration of employment or time since first employment. Uterine cancer among women was the only cause of death with a significantly increased standardized mortality ratio. Five of the seven women worked in office jobs. This study confirmed the lack of an increase in mortality from lung cancer and nonmalignant respiratory diseases related to insoluble beryllium compounds. PMID:24589746

  14. A mortality study of workers exposed to insoluble forms of beryllium.

    PubMed

    Boffetta, Paolo; Fordyce, Tiffani; Mandel, Jack S

    2014-11-01

    This study investigated lung cancer and other diseases related to insoluble beryllium compounds. A cohort of 4950 workers from four US insoluble beryllium manufacturing facilities were followed through 2009. Expected deaths were calculated using local and national rates. On the basis of local rates, all-cause mortality was significantly reduced. Mortality from lung cancer (standardized mortality ratio 96.0; 95% confidence interval 80.0, 114.3) and from nonmalignant respiratory diseases was also reduced. There were no significant trends for either cause of death according to duration of employment or time since first employment. Uterine cancer among women was the only cause of death with a significantly increased standardized mortality ratio. Five of the seven women worked in office jobs. This study confirmed the lack of an increase in mortality from lung cancer and nonmalignant respiratory diseases related to insoluble beryllium compounds.

  15. Tough and elastic hydrogel of hyaluronic acid and chondroitin sulfate as potential cell scaffold materials.

    PubMed

    Ni, Yilu; Tang, Zhurong; Cao, Wanxu; Lin, Hai; Fan, Yujiang; Guo, Likun; Zhang, Xingdong

    2015-03-01

    Natural polysaccharides are extensively investigated as cell scaffold materials for cellular adhesion, proliferation, and differentiation due to their excellent biocompatibility, biodegradability, and biofunctions. However, their application is often severely limited by their mechanical behavior. In this study, a tough and elastic hydrogel scaffold was prepared with hyaluronic acid (HA) and chondroitin sulfate (CS). HA and CS were conjugated with tyramine (TA) and the degree of substitution (DS) was 10.7% and 11.3%, respectively, as calculated by (1)H NMR spectra. The hydrogel was prepared by mixing HA-TA and CS-TA in presence of H2O2 and HRP. The sectional morphology of hydrogels was observed by SEM, static and dynamic mechanical properties were analyzed by Shimadzu electromechanical testing machine and dynamic mechanical thermal analyzer Q800. All samples showed good ability to recover their appearances after deformation, the storage modulus (E') of hydrogels became higher as the testing frequency went up. Hydrogels also showed fatigue resistance to cyclic compression. Mesenchymal stem cells encapsulated in hydrogels showed good cell viability as detected by CLSM. This study suggests that the hydrogels have both good mechanical properties and biocompatibility, and may serve as model systems to explore mechanisms of deformation and energy dissipation or find some applications in tissue engineering.

  16. Use of wet FGD material for revegetation of an abandoned acidic coal refuse pile

    SciTech Connect

    Mafi, S.; Stehouwer, R.C.

    1996-12-31

    Wet FGD material has a neutralizing potential of 15% CaCO{sub 3}. These properties may make it a beneficial amendment for revegetation of hyper-acidic coal refuse. In greenhouse and field experiments, coal refuse (pH = 2.5) was amended with wet FGD (300, 500, and 700 tons/acre). Amendment with FGD was as effective as agricultural lime (AL) in increasing refuse pH and decreasing soluble Al and Fe. Addition of compost to the FGD further increased pH and decreased soluble Al and Fe. Downward transport of Ca was greater with FGD than AL, but FGD did not increase leachate concentrations of S. Amendment with FGD increased refuse, leachate and plant tissue concentrations of B. Other trace elements were not increased by FGD. In the greenhouse, plant growth was similar with AL and FGD except during the first three months when AL produced more growth than FGD. The initial growth suppression by FGD was likely due to high soluble salts, and possibly by high B concentrations. During the first year of the field experiment plant growth was greater with FGD than with AL. In both the field and greenhouse experiments compost increased plant growth when combined with FGD. These experiments show revegetation of toxic coal refuse and improvement in drainage water quality is possible by amendment with FGD. Revegetation success will be improved by combined amendment with FGD and compost.

  17. Hydrothermal treatment of MSWI bottom ash forming acid-resistant material

    SciTech Connect

    Etoh, Jiro Kawagoe, Takeshi; Shimaoka, Takayuki; Watanabe, Koichiro

    2009-03-15

    To recycle municipal solid waste incinerator (MSWI) bottom ash, synthesis of hydrothermal minerals from bottom ash was performed to stabilize heavy metals. MSWI bottom ash was mixed with SiO{sub 2}, Al(OH){sub 3}, and Mg(OH){sub 2} so its chemical composition was similar to that of hydrothermal clay minerals. These solid specimens were mixed with water at a liquid/solid ratio of 5. The reaction temperature was 200 deg. C, and reactions were performed for 24-240 h. Generation of kaolinite/smectite mixed-layer clay mineral was found in the samples after the reaction of the mixture of bottom ash, SiO{sub 2}, and Mg(OH){sub 2}. Calcium silicate hydrate minerals such as tobermorite and xonotlite were also generated. X-ray powder diffraction suggested the presence of amorphous materials. Leaching tests at various pHs revealed that the concentration of heavy metals in the leachates from MSWI bottom ash hydrothermally treated with SiO{sub 2} and Mg(OH){sub 2} was lower than that in leachates from non-treated bottom ash, especially under acid conditions. Hydrothermal treatment with modification of chemical composition may have potential for the recycling of MSWI bottom ash.

  18. Oxalic acid-assisted combustion synthesized LiVO3 cathode material for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Jian, X. M.; Wenren, H. Q.; Huang, S.; Shi, S. J.; Wang, X. L.; Gu, C. D.; Tu, J. P.

    2014-01-01

    LiVO3 materials are synthesized by combustion method with oxalic acid as fuel. Owing to its relatively low crystallization and small particle size, the LiVO3 calcined at 450 °C for 2 h displays optimal electrochemical performances, delivering a high discharge capacity of 298.4 mAh g-1 and 262.5 mAh g-1 between 1.0 and 3.5 V at a current density of 50 mA g-1 and 500 mA g-1 respectively, and exhibiting good cyclic stability. In this work, the chemical diffusion coefficient of Li+ (DLi+) in the LiVO3 electrode is determined by electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT). The value calculated by EIS is in the range of 10-9-10-8 cm2 s-1, while it calculated by GITT is 10-9.5-10-8 cm2 s-1.

  19. Beef, chicken and lamb fatty acid analysis--a simplified direct bimethylation procedure using freeze-dried material.

    PubMed

    Lee, M R F; Tweed, J K S; Kim, E J; Scollan, N D

    2012-12-01

    When fractionation of meat lipids is not required, procedures such as saponification can be used to extract total fatty acids, reducing reliance on toxic organic compounds. However, saponification of muscle fatty acids is laborious, and requires extended heating times, and a second methylation step to convert the extracted fatty acids to fatty acid methyl esters prior to gas chromatography. Therefore the development of a more rapid direct methylation procedure would be of merit. The use of freeze-dried material for analysis is common and allows for greater homogenisation of the sample. The present study investigated the potential of using freeze-dried muscle samples and a direct bimethylation to analyse total fatty acids of meat (beef, chicken and lamb) in comparison with a saponification procedure followed by bimethylation. Both methods compared favourably for all major fatty acids measured. There was a minor difference in relation to the C18:1 trans 10 isomer with a greater (P<0.05) recovery with saponification. However, numerically the difference was small and likely as a result of approaching the limits of isomer identification by single column gas chromatography. Differences (P<0.001) between species were found for all fatty acids measured with no interaction effects. The described technique offers a simplified, quick and reliable alternative to saponification to analyse total fatty acids from muscle samples.

  20. The effect of water on the mechanical properties of soluble and insoluble ceramic cements.

    PubMed

    Koh, Ilsoo; López, Alejandro; Pinar, Ana B; Helgason, Benedikt; Ferguson, Stephen J

    2015-11-01

    Ceramic cements are good candidates for the stabilization of fractured bone due to their potential ease of application and biological advantages. New formulations of ceramic cements have been tested for their mechanical properties, including strength, stiffness, toughness and durability. The changes in the mechanical properties of a soluble cement (calcium sulfate) upon water-saturation (saturation) was reported in our previous study, highlighting the need to test ceramic cements using saturated samples. It is not clear if the changes in the mechanical properties of ceramic cements are exclusive to soluble cements. Therefore the aim of the present study was to observe the changes in the mechanical properties of soluble and insoluble ceramic cements upon saturation. A cement with high solubility (calcium sulfate dihydrate, CSD) and a cement with low solubility (dicalcium phosphate dihydrate, DCPD) were tested. Three-point bending tests were performed on four different groups of: saturated CSD, non-saturated CSD, saturated DCPD, and non-saturated DCPD samples. X-ray diffraction analysis and scanning electron microscopy were also performed on a sample from each group. Flexural strength, effective flexural modulus and flexural strain at maximum stress, lattice volume, and crystal sizes and shape were compared, independently, between saturated and non-saturated groups of CSD and DCPD. Although material dissolution did not occur in all cases, all calculated mechanical properties decreased significantly in both CSD and DCPD upon saturation. The results indicate that the reductions in the mechanical properties of saturated ceramic cements are not dependent on the solubility of a ceramic cement. The outcome raised the importance of testing any implantable ceramic cements in saturated condition to estimate its in vivo mechanical properties.

  1. Gelation properties of spent duck meat surimi-like material produced using acid-alkaline solubilization methods.

    PubMed

    Nurkhoeriyati, T; Huda, N; Ahmad, R

    2011-01-01

    The gelation properties of spent duck meat surimi-like material produced using acid solubilization (ACS) or alkaline solubilization (ALS) were studied and compared with conventionally processed (CON) surimi-like material. The ACS process yielded the highest protein recovery (P < 0.05). The ALS process generated the highest lipid reduction, and the CON process yielded the lowest reduction (P < 0.05). Surimi-like material produced by the CON process had the highest gel strength, salt extractable protein (SEP), and water holding capacity (WHC), followed by materials produced via the ALS and ACS processes and untreated duck meat (P < 0.05). The material produced by the CON process also had the highest cohesiveness, hardness, and gumminess values and the lowest springiness value. Material produced by the ACS and ALS processes had higher whiteness values than untreated duck meat gels and gels produced by the CON method (P < 0.05). Surimi-like material produced using the ACS and CON processes had significantly higher myoglobin removal (P < 0.05) than that produced by the ALS method and untreated duck meat. Among all surimi-like materials, the highest Ca(2+)-ATPase activity was found in conventionally produced gels (P < 0.05). This suggests that protein oxidation was induced by acid-alkaline solubilization. The gels produced by ALS had a significantly lower (P < 0.05) total SH content than the other samples. This result showed that the acid-alkaline solubilization clearly improved gelation and color properties of spent duck and possibly applied for other high fat raw material.

  2. Comparison of four digestion procedures not requiring perchloric acid for the trace-element analysis of plant material

    SciTech Connect

    Knight, M. J.

    1980-05-01

    Perchloric acid (HClO/sub 4/) is often used to destroy organic material contained in plant tissue during sample preparation for trace-element analysis. However, since perchloric acid is an extremely strong oxidizing agent that can cause fire and explosion when in contact with combustible materials, its use is best avoided when proper safety equipment and training is unavailable. A comparison was made of four digestion procedures that do not require perchloric acid: wet digestion with nitric and sulfuric acids; wet digestion with nitric acid alone; a repeated wet digestion with nitric acid; and direct dry ashing. Each procedure was used to digest National Bureau of Standards orchard leaves (SRM 1571). To investigate the effect of possible filter paper adsorption on the determination of trace elements, digested samples were either filtered or not filtered before analysis. Atomic absorption spectrophotometry was employed to determine concentrations of As, Be, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, and Zn in each digested sample. Recoveries of each element and the relative error of each determination for each digestion procedure were then calculated. A statistical analysis of these data indicates that the direct dry ashing procedure is best suited for multi-element analysis. Dry ashing is appropriate to recover As, Be, Cr, Cu, Fe, Mn, Mo, Pb, and Zn. The nitric-sulfuric acids, nitric acid, and repeated nitric acid digestion procedures were deemed poor for multi-element analysis; however, each proved useful for the recovery of certain individual elements, including Cd, Pb, and Zn. Sample filtration significantly (p less than or equal to 0.05) lowered the recovery of Cr, Mn, Pb, and Zn from the digested samples. Conversely, the recovery of As, Mo, and Sr was significantly (p less than or equal to 0.05) higher in samples filtered before analysis when compared to the recovery of these elements in unfiltered samples.

  3. An In Situ Method for Sizing Insoluble Residues in Precipitation and Other Aqueous Samples.

    PubMed

    Axson, Jessica L; Creamean, Jessie M; Bondy, Amy L; Capracotta, Sonja S; Warner, Katy Y; Ault, Andrew P

    2015-01-01

    Particles are frequently incorporated into clouds or precipitation, influencing climate by acting as cloud condensation or ice nuclei, taking up coatings during cloud processing, and removing species through wet deposition. Many of these particles, particularly ice nuclei, can remain suspended within cloud droplets/crystals as insoluble residues. While previous studies have measured the soluble or bulk mass of species within clouds and precipitation, no studies to date have determined the number concentration and size distribution of insoluble residues in precipitation or cloud water using in situ methods. Herein, for the first time we demonstrate that Nanoparticle Tracking Analysis (NTA) is a powerful in situ method for determining the total number concentration, number size distribution, and surface area distribution of insoluble residues in precipitation, both of rain and melted snow. The method uses 500 μL or less of liquid sample and does not require sample modification. Number concentrations for the insoluble residues in aqueous precipitation samples ranged from 2.0-3.0(±0.3)×10(8) particles cm(-3), while surface area ranged from 1.8(±0.7)-3.2(±1.0)×10(7) μm(2) cm(-3). Number size distributions peaked between 133-150 nm, with both single and multi-modal character, while surface area distributions peaked between 173-270 nm. Comparison with electron microscopy of particles up to 10 μm show that, by number, > 97% residues are <1 μm in diameter, the upper limit of the NTA. The range of concentration and distribution properties indicates that insoluble residue properties vary with ambient aerosol concentrations, cloud microphysics, and meteorological dynamics. NTA has great potential for studying the role that insoluble residues play in critical atmospheric processes.

  4. An In Situ Method for Sizing Insoluble Residues in Precipitation and Other Aqueous Samples

    PubMed Central

    Axson, Jessica L.; Creamean, Jessie M.; Bondy, Amy L.; Capracotta, Sonja S.; Warner, Katy Y.; Ault, Andrew P.

    2015-01-01

    Particles are frequently incorporated into clouds or precipitation, influencing climate by acting as cloud condensation or ice nuclei, taking up coatings during cloud processing, and removing species through wet deposition. Many of these particles, particularly ice nuclei, can remain suspended within cloud droplets/crystals as insoluble residues. While previous studies have measured the soluble or bulk mass of species within clouds and precipitation, no studies to date have determined the number concentration and size distribution of insoluble residues in precipitation or cloud water using in situ methods. Herein, for the first time we demonstrate that Nanoparticle Tracking Analysis (NTA) is a powerful in situ method for determining the total number concentration, number size distribution, and surface area distribution of insoluble residues in precipitation, both of rain and melted snow. The method uses 500 μL or less of liquid sample and does not require sample modification. Number concentrations for the insoluble residues in aqueous precipitation samples ranged from 2.0–3.0(±0.3)×108 particles cm−3, while surface area ranged from 1.8(±0.7)–3.2(±1.0)×107 μm2 cm−3. Number size distributions peaked between 133–150 nm, with both single and multi-modal character, while surface area distributions peaked between 173–270 nm. Comparison with electron microscopy of particles up to 10 μm show that, by number, > 97% residues are <1 μm in diameter, the upper limit of the NTA. The range of concentration and distribution properties indicates that insoluble residue properties vary with ambient aerosol concentrations, cloud microphysics, and meteorological dynamics. NTA has great potential for studying the role that insoluble residues play in critical atmospheric processes. PMID:25705069

  5. Application of a radiometric method for evaluation of loss of salicylic acid during isolation from biologic material.

    PubMed

    Ostrowski, A

    1983-01-01

    A radiometric method for evaluation of loss of salicylic acid in the process of isolation from biologic material is described. According to this study the mean loss during the total process of isolation amounts to 33.59%, the specific values being 19.47% during protein precipitation, 10.68% during extraction, and 3.44% during evaporation of solvent.

  6. Electrophilic acid gas-reactive fluid, proppant, and process for enhanced fracturing and recovery of energy producing materials

    DOEpatents

    Fernandez, Carlos A.; Heldebrant, David J.; Bonneville, Alain H. R.; Jung, Hun Bok; Carroll, Kenneth

    2016-09-20

    An electrophilic acid gas-reactive fracturing and recovery fluid, proppant, and process are detailed. The fluid expands in volume to provide rapid and controlled increases in pressure that enhances fracturing in subterranean bedrock for recovery of energy-producing materials. Proppants stabilize openings in fractures and fissures following fracturing.

  7. Pulmonary granulomatous vasculitis induced by insoluble particulates: a case report.

    PubMed

    Hammar, Samuel P; Williams, M Glenn; Dodson, Ronald F

    2003-01-01

    The authors report a case of a 39-year-old woman who sustained an injury to her left knee requiring arthroscopic surgical medial menisectomy and ganglionic block for reflex sympathetic dystrophy syndrome. Approximately 1 year after injury, the patient presented with an elevated white blood cell count and fever and was diagnosed to have a psoas muscle abscess, which was treated with antibiotics. She was also taking 4 different oral medications that contained microcrystalline cellulose as a filter. Approximately 1 month after being diagnosed with the psoas muscle abscess, the patient developed shortness of breath, marked weakness, diaphoresis, and intermittent emesis. She became hypotensive and tachyneic and expired. Postmortem examination showed granulomatous vasculitis with extensive occlusions of pulmonary arteries by birefringent crystalline material identified to be cellulose histochemically and by analytical electron microscopy evaluation. This case report describes the ultrastructural and chemical features of various medicinal tablet fillers and compares them to pure samples. This report also demonstrates the usefulness of analytical electron microscopy in accurately identifying birefringent material in lung tissue.

  8. Development of High-purity Certified Reference Materials for 17 Proteinogenic Amino Acids by Traceable Titration Methods.

    PubMed

    Kato, Megumi; Yamazaki, Taichi; Kato, Hisashi; Eyama, Sakae; Goto, Mari; Yoshioka, Mariko; Takatsu, Akiko

    2015-01-01

    To ensure the reliability of amino acid analyses, the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has developed high-purity certified reference materials (CRMs) for 17 proteinogenic amino acids. These CRMs are intended for use as primary reference materials to enable the traceable quantification of amino acids. The purity of the present CRMs was determined based on two traceable methods: nonaqueous acidimetric titration and nitrogen determination by the Kjeldahl method. Since neither method could distinguish compounds with similar structures, such as amino acid-related impurities, impurities were thoroughly quantified by combining several HPLC methods, and subtracted from the obtained purity of each method. The property value of each amino acid was calculated as a weighted mean of the corrected purities by the two methods. The uncertainty of the property value was obtained by combining measurement uncertainties of the two methods, a difference between the two methods, the uncertainty from the contribution of impurities, and the uncertainty derived from inhomogeneity. The uncertainty derived from instability was considered to be negligible based on stability monitoring of some CRMs. The certified value of each amino acid, property value with uncertainty, was given for both with or without enantiomeric separation.

  9. Overexpression of Aspergillus tubingensis faeA in protease-deficient Aspergillus niger enables ferulic acid production from plant material.

    PubMed

    Zwane, Eunice N; Rose, Shaunita H; van Zyl, Willem H; Rumbold, Karl; Viljoen-Bloom, Marinda

    2014-06-01

    The production of ferulic acid esterase involved in the release of ferulic acid side groups from xylan was investigated in strains of Aspergillus tubingensis, Aspergillus carneus, Aspergillus niger and Rhizopus oryzae. The highest activity on triticale bran as sole carbon source was observed with the A. tubingensis T8.4 strain, which produced a type A ferulic acid esterase active against methyl p-coumarate, methyl ferulate and methyl sinapate. The activity of the A. tubingensis ferulic acid esterase (AtFAEA) was inhibited twofold by glucose and induced twofold in the presence of maize bran. An initial accumulation of endoglucanase was followed by the production of endoxylanase, suggesting a combined action with ferulic acid esterase on maize bran. A genomic copy of the A. tubingensis faeA gene was cloned and expressed in A. niger D15#26 under the control of the A. niger gpd promoter. The recombinant strain has reduced protease activity and does not acidify the media, therefore promoting high-level expression of recombinant enzymes. It produced 13.5 U/ml FAEA after 5 days on autoclaved maize bran as sole carbon source, which was threefold higher than for the A. tubingensis donor strain. The recombinant AtFAEA was able to extract 50 % of the available ferulic acid from non-pretreated maize bran, making this enzyme suitable for the biological production of ferulic acid from lignocellulosic plant material.

  10. Clay-Nucleic Acid Complexes: Characteristics and Implications for the Preservation of Genetic Material in Primeval Habitats

    NASA Astrophysics Data System (ADS)

    Franchi, Marco; Bramanti, Emilia; Morassi Bonzi, Laura; Luigi Orioli, Pier; Vettori, Cristina; Gallori, Enzo

    1999-05-01

    The equilibrium adsorption of three nucleic acids: chromosomal DNA, supercoiled plasmid DNA, and 25S rRNA, on the clay minerals, montmorillonite (M) and kaolinite (K), were studied. Adsorption of the nucleic acid on the clays was rapid and maximal after 90 min of contact time. Chromosomal DNA was adsorbed to a greater extent than plasmid DNA and RNA, and the adsorption was also greater on M than on K. Adsorption isotherms were of the L type, and a plateau was reached with all the complexes, with the exception of chromosomal DNA adsorbed on M. To determine where nucleic acids are adsorbed on clay minerals and the nature of the interaction, complexes were studied by X-ray diffraction (X-RD), electron microscopy, and Fourier transform infrared (FT-IR) spectroscopy. X-RD showed that nucleic acids did not penetrate the clay, indicating that the adsorption occurred primarily on the external surfaces of clay particles, as also suggested by electron microscopy observations. FT-IR spectra of clay-tightly bound nucleic acid complexes showed absorption bands that indicate a variation of the nucleic acids status as a consequence of their adsorption on clay. Data obtained suggested that the formation of clay-nucleic acid complex could have an important role in the preservation of genetic material in primeval habitats.

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

    PubMed

    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

  12. The fluorimetric determination of oxalic acid in blood and other biological materials

    PubMed Central

    Zarembski, P. M.; Hodgkinson, A.

    1965-01-01

    1. Oxalic acid is separated from interfering substances by extraction with tri-n-butyl phosphate followed by co-precipitation with calcium sulphate. The precipitated oxalic acid is then reduced to glyoxylic acid, which is coupled with resorcinol to form a coloured fluorescent complex. 2. The spectrofluorometric method described is sensitive and highly specific, the minimum detectable amount of oxalic acid being 0·9μmole under the recommended conditions. 3. The concentration of oxalic acid in blood from 15 normal adults was 200–320μg./100ml. For serum the range was 135–280μg./100ml. The urinary excretion of oxalic acid by 60 normal adults on a normal diet was 9·0–28·5mg./24hr. PMID:5862411

  13. Insoluble carob fiber rich in polyphenols lowers total and LDL cholesterol in hypercholesterolemic sujects.

    PubMed

    Ruiz-Roso, Baltasar; Quintela, José C; de la Fuente, Ester; Haya, Javier; Pérez-Olleros, Lourdes

    2010-03-01

    Recently, polyphenols have been found to affect blood lipids in animals in a similar manner as soluble dietary fibre. The aim was to assess whether an insoluble dietary fiber very rich in polyphenols has a beneficial effect on serum lipids in humans. In a double-blind randomized placebo-controlled clinical study with parallel arms, 88 volunteers with hypercholesterolemia were randomly assigned to consume daily either, fiber with insoluble 84% polyphenols 4 g twice a day (n = 43) or placebo (n = 45). Serum total, LDL and HDL cholesterol and triglycerides were assessed at baseline and after 4 weeks. The insoluble polyphenols consumption reduced the total cholesterol by 17.8 +/- 6.1% (p < 0.05), LDL cholesterol by 22.5 +/- 8.9% (p < 0.001), LDL: HDL cholesterol ratio by 26.2 +/- 14.3% (p < 0.001) and triglycerides by 16.3 +/- 23.4% (p < 0.05) at the end of the study compared with baseline. No significant differences were found during the study time in the placebo group for the lipid profile. The consumption of fiber very rich in insoluble polyphenols shows beneficial effects on human blood lipid profile and may be effective in prevention and treatment of hyperlipemia.

  14. Nonidet P-40 extraction of lymphocyte plasma membrane. Characterization of the insoluble residue.

    PubMed

    Davies, A A; Wigglesworth, N M; Allan, D; Owens, R J; Crumpton, M J

    1984-04-01

    Purified preparations of lymphocyte plasma membrane were extracted exhaustively with Nonidet P-40 in Dulbecco's phosphate-buffered saline medium. The insoluble fraction, as defined by sedimentation at 10(6) g-min, contained about 10% of the membrane protein as well as cholesterol and phospholipid. The lipid/protein ratio, cholesterol/phospholipid ratio and sphingomyelin content were increased in the residue. Density-gradient centrifugation suggested that the lipid and protein form a common entity. As judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, the Nonidet P-40-insoluble fractions of the plasma membranes of human B lymphoblastoid cells and pig mesenteric lymph-node lymphocytes possessed similar qualitative polypeptide compositions but differed quantitatively. Both residues comprised major polypeptides of Mr 28 000, 33 000, 45 000 and 68 000, together with a prominent band of Mr 120 000 in the human and of Mr 200 000 in the pig. The polypeptides of Mr 28 000, 33 000, 68 000 and 120 000 were probably located exclusively in the Nonidet P-40-insoluble residue, which also possessed a 4-fold increase in 5'-nucleotidase specific activity. The results indicate that a reproducible fraction of lymphocyte plasma membrane is insoluble in non-ionic detergents and that this fraction possesses a unique polypeptide composition. By analogy with similar studies with erythrocyte ghosts, it appears likely that the polypeptides are located on the plasma membrane's cytoplasmic face.

  15. Insoluble dietary fiber of wheat bran increased viscosity of pig whole cecal contents in vitro.

    PubMed

    Sakata, Takashi; Saito, Masaaki

    2007-08-01

    Viscosity of whole pig cecal contents with (2 g/200 mL) or without insoluble dietary fibers prepared from wheat bran of two particle sizes (WB fine 0.22+/-0.22 mm(2), n=1,723; WB coarse 0.51+/-1.12 mm(2), n=1,457, mean+/-SD) was measured using a rotary viscometer equipped with a vane spindle at the shear rates of 0.05, 0.16, 0.47, 0.78 and 1.56 (s(-1)) and at 0 and 2 h. Such measurements were repeated twice each for five different donor pig groups. We were able to measure the coefficient of viscosity of such samples over a wide range of shear rate. Coefficient of viscosity depended on shear rate. Addition of insoluble dietary fiber increased the coefficient of viscosity. Insoluble dietary fiber from WB coarse had a significantly stronger effect than that from WB fine. The above results demonstrated that insoluble dietary fibers of wheat bran increase the viscosity of gut contents, and thereby potentially retard digestion and absorption.

  16. A kinetic model for heterogeneous condensation of vapor on an insoluble spherical particle.

    PubMed

    Luo, Xisheng; Fan, Yu; Qin, Fenghua; Gui, Huaqiao; Liu, Jianguo

    2014-01-14

    A kinetic model is developed to describe the heterogeneous condensation of vapor on an insoluble spherical particle. This new model considers two mechanisms of cluster growth: direct addition of water molecules from the vapor and surface diffusion of adsorbed water molecules on the particle. The effect of line tension is also included in the model. For the first time, the exact expression of evaporation coefficient is derived for heterogeneous condensation of vapor on an insoluble spherical particle by using the detailed balance. The obtained expression of evaporation coefficient is proved to be also correct in the homogeneous condensation and the heterogeneous condensation on a planar solid surface. The contributions of the two mechanisms to heterogeneous condensation including the effect of line tension are evaluated and analysed. It is found that the cluster growth via surface diffusion of adsorbed water molecules on the particle is more important than the direct addition from the vapor. As an example of our model applications, the growth rate of the cap shaped droplet on the insoluble spherical particle is derived. Our evaluation shows that the growth rate of droplet in heterogeneous condensation is larger than that in homogeneous condensation. These results indicate that an explicit kinetic model is benefit to the study of heterogeneous condensation on an insoluble spherical particle.

  17. Turning a Water And Oil Insoluble Cisplatin Derivative into a Nanoparticle Formulation for Cancer Therapy

    PubMed Central

    Guo, Shutao; Wang, Yuhua; Miao, Lei; Xu, Zhenghong; Lin, C. Michael; Huang, Leaf

    2014-01-01

    The formulation of water insoluble organic compounds into nanoparticles has become a widely established method for enhancing the delivery and efficacy of cancer therapeutics. Therefore, a comparable approach when applied to water insoluble inorganic compounds should also promote similar advantages. Herein, we have successfully formulated insoluble iodinated cisplatin (CDDP-I) into a LPI NPs (lipid-coated iodinated CDDP nanoparticles). Two separate microemulsions were combined, each containing a precursor for the synthesis of CDDP-I. The resulting CDDP-I precipitate was then coated with an anionic lipid and dispersed in water with the help of an additional lipid. This method allows us to effectively encapsulate CDDP-I and was able to achieve a considerable drug loading of 82 wt%. Administered LPI NPs demonstrated high level accumulation in tumor tissues and exhibited an anti-cancer activity comparable to free CDDP in two melanoma xenograft models without inducing nephrotoxocity. The benefits offered through this delivery formulation are not unique to CDDP-I, as this versatile platform may be extended to the formulation of other inorganic compounds that are both water and oil insoluble into nanoparticles for superior anticancer efficacy. PMID:24920436

  18. Development of a new ferulic acid certified reference material for use in clinical chemistry and pharmaceutical analysis

    PubMed Central

    Yang, Dezhi; Wang, Fengfeng; Zhang, Li; Gong, Ningbo; Lv, Yang

    2015-01-01

    This study compares the results of three certified methods, namely differential scanning calorimetry (DSC), the mass balance (MB) method and coulometric titrimetry (CT), in the purity assessment of ferulic acid certified reference material (CRM). Purity and expanded uncertainty as determined by the three methods were respectively 99.81%, 0.16%; 99.79%, 0.16%; and 99.81%, 0.26% with, in all cases, a coverage factor (k) of 2 (P=95%). The purity results are consistent indicating that the combination of DSC, the MB method and CT provides a confident assessment of the purity of suitable CRMs like ferulic acid. PMID:26579451

  19. Development of a new ferulic acid certified reference material for use in clinical chemistry and pharmaceutical analysis.

    PubMed

    Yang, Dezhi; Wang, Fengfeng; Zhang, Li; Gong, Ningbo; Lv, Yang

    2015-05-01

    This study compares the results of three certified methods, namely differential scanning calorimetry (DSC), the mass balance (MB) method and coulometric titrimetry (CT), in the purity assessment of ferulic acid certified reference material (CRM). Purity and expanded uncertainty as determined by the three methods were respectively 99.81%, 0.16%; 99.79%, 0.16%; and 99.81%, 0.26% with, in all cases, a coverage factor (k) of 2 (P=95%). The purity results are consistent indicating that the combination of DSC, the MB method and CT provides a confident assessment of the purity of suitable CRMs like ferulic acid.

  20. [Analysis of volcanic-ash-based insoluble ingredients of facial cleansers].

    PubMed

    Ikarashi, Yoshiaki; Uchino, Tadashi; Nishimura, Tetsuji

    2011-01-01

    The substance termed "Shirasu balloons", produced by the heat treatment of volcanic silicates, is in the form of hollow glass microspheres. Recently, this substance has gained popularity as an ingredient of facial cleansers currently available in the market, because it lends a refreshing and smooth feeling after use. However, reports of eye injury after use of a facial cleanser containing a substance made from volcanic ashes are on the rise. We presumed that the shape and size of these volcanic-ash-based ingredients would be the cause of such injuries. Therefore, in this study, we first developed a method for extracting water-insoluble ingredients such as "Shirasu balloons" from the facial cleansers, and then, we examined their shapes and sizes. The insoluble ingredients extracted from the cleansers were mainly those derived from volcanic silicates. A part of the ingredients remained in the form of glass microspheres, but for the most part, the ingredients were present in various forms, such as fragments of broken glass. Some of the fragments were larger than 75 microm in length. Foreign objects having a certain hardness, shape, and size (e.g., size greater than 75 microm) can possibly cause eye injury. We further examined insoluble ingredients of facial scrubs, such as artificial mineral complexes, mud, charcoal, and polymers, except for volcanic-silicate-based ingredients. The amounts of insoluble ingredients extracted from these scrubs were small and did not have a sharp edge. Some scrubs had ingredients with particles larger than 75 microm in size, but their specific gravities were small and their hardness values were much lower than those of glass microspheres of ingredients such as "Shirasu balloons". Because the fragments of glass microspheres can possibly cause eye injury, the facial cleansers containing large insoluble ingredients derived from volcanic ashes should be avoided to use around eyes.

  1. Acid Precipitation Learning Materials: Science, Environmental and Social Studies, Grades 6-12.

    ERIC Educational Resources Information Center

    Hessler, Edward W.

    The major environmental problem of acid precipition is addressed through a series of activities contained in this guide for teachers of grades 6 through 12. Exercises are provided to help students learn science inquiry skills, facts, and concepts while focusing on the acid rain situation. Activities are organized by content areas. These include:…

  2. Effects of chemical and enzymatic modifications on starch-linoleic acid complex formation.

    PubMed

    Arijaje, Emily Oluwaseun; Wang, Ya-Jane

    2017-02-15

    This study investigated the complexation yield and physicochemical properties of soluble and insoluble starch complexes with linoleic acid when a β-amylase treatment was applied to acetylated and debranched potato starch. The degree of acetylation was generally higher in the soluble complexes than in the insoluble ones. The insoluble complexes from the acetylated starch displayed the V-type pattern, whereas, the soluble complexes displayed a mixture of either the A-/V-type or the B-/V-type pattern. Acetylation decreased onset and peak melting temperatures for the insoluble complexes, whereas no melting endotherm was observed in the soluble complexes. Acetylation substantially increased the amount of complexed linoleic acid in the insoluble complexes, but had little positive effect on the formation of the soluble complexes. The β-amylase treatment significantly increased the complexed linoleic content in both soluble and insoluble complexes for the low acetylated starch, but not for the high acetylated starch.

  3. Comparative Evaluation of Shear Bond Strength of Luting Cements to Different Core Buildup Materials in Lactic Acid Buffer Solution

    PubMed Central

    Patil, Siddharam M.; Desai, Raviraj G.; Arabbi, Kashinath C.; Prakash, Ved

    2015-01-01

    Aim and Objectives The core buildup material is used to restore badly broken down tooth to provide better retention for fixed restorations. The shear bond strength of a luting agent to core buildup is one of the crucial factors in the success of the cast restoration. The aim of this invitro study was to evaluate and compare the shear bond strength of luting cements with different core buildup materials in lactic acid buffer solution. Materials and Methods Two luting cements {Traditional Glass Ionomer luting cement (GIC) and Resin Modified Glass Ionomer luting cement (RMGIC)} and five core buildup materials {Silver Amalgam, Glass ionomer (GI), Glass Ionomer Silver Reinforced (GI Silver reinforced), Composite Resin and Resin Modified Glass Ionomer(RMGIC)} were selected for this study. Total 100 specimens were prepared with 20 specimens for each core buildup material using a stainless steel split metal die. Out of these 20 specimens, 10 specimens were bonded with each luting cement. All the bonded specimens were stored at 370c in a 0.01M lactic acid buffer solution at a pH of 4 for 7days. Shear bond strength was determined using a Universal Testing Machine at a cross head speed of 0.5mm/min. The peak load at fracture was recorded and shear bond strength was calculated. The data was statistically analysed using Two-way ANOVA followed by HOLM-SIDAK method for pair wise comparison at significance level of p<0.05. Results Two-Way ANOVA showed significant differences in bond strength of the luting cements (p<0.05) and core materials (p<0.05) and the interactions (p<0.05). Pairwise comparison of luting cements by HOLM-SIDAK test, showed that the RMGIC luting cement had higher shear bond strength values than Traditional GIC luting cement for all the core buildup materials. RMGIC core material showed higher bond strength values followed by Composite resin, GI silver reinforced, GI and silver amalgam core materials for both the luting agents. Conclusion Shear bond strength of

  4. A novel sodium N-fatty acyl amino acid surfactant using silkworm pupae as stock material

    NASA Astrophysics Data System (ADS)

    Wu, Min-Hui; Wan, Liang-Ze; Zhang, Yu-Qing

    2014-03-01

    A novel sodium N-fatty acyl amino acid (SFAAA) surfactant was synthesized using pupa oil and pupa protein hydrolysates (PPH) from a waste product of the silk industry. The aliphatic acids from pupa oil were modified into N-fatty acyl chlorides by thionyl chloride (SOCl2). SFAAA was synthesized using acyl chlorides and PPH. GC-MS analysis showed fatty acids from pupa oil consist mainly of unsaturated linolenic and linoleic acids and saturated palmitic and stearic acids. SFAAA had a low critical micelle concentration, great efficiency in lowering surface tension and strong adsorption at an air/water interface. SFAAA had a high emulsifying power, as well as a high foaming power. The emulsifying power of PPH and SFAAA in an oil/water emulsion was better with ethyl acetate as the oil phase compared to n-hexane. The environment-friendly surfactant made entirely from silkworm pupae could promote sustainable development of the silk industry.

  5. A novel sodium N-fatty acyl amino acid surfactant using silkworm pupae as stock material.

    PubMed

    Wu, Min-Hui; Wan, Liang-Ze; Zhang, Yu-Qing

    2014-03-21

    A novel sodium N-fatty acyl amino acid (SFAAA) surfactant was synthesized using pupa oil and pupa protein hydrolysates (PPH) from a waste product of the silk industry. The aliphatic acids from pupa oil were modified into N-fatty acyl chlorides by thionyl chloride (SOCl2). SFAAA was synthesized using acyl chlorides and PPH. GC-MS analysis showed fatty acids from pupa oil consist mainly of unsaturated linolenic and linoleic acids and saturated palmitic and stearic acids. SFAAA had a low critical micelle concentration, great efficiency in lowering surface tension and strong adsorption at an air/water interface. SFAAA had a high emulsifying power, as well as a high foaming power. The emulsifying power of PPH and SFAAA in an oil/water emulsion was better with ethyl acetate as the oil phase compared to n-hexane. The environment-friendly surfactant made entirely from silkworm pupae could promote sustainable development of the silk industry.

  6. Materialism.

    PubMed

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website.

  7. Preparation and characterization of 5-sulphosalicylic acid doped tetraethoxysilane composite ion-exchange material by sol-gel method.

    PubMed

    Rehman, Suhail-ul; Islam, Nasarul; Ahad, Sozia; Fatima, Syed Zeeshan; Pandith, Altaf Hussain

    2013-09-15

    In this manuscript, we report the preparation and characterization of sulphosalicylic doped tetraethoxysilane (SATEOS), composite material by sol-gel method as a new ion exchanger for the removal of Ni(II) from aqueous solution. The fine granular material was prepared by acid catalyzed condensation polymerization through sol-gel mechanism in the presence of cationic surfactant. The material has an ion exchange capacity of 0.64 mequiv./g(dry) for sodium ions, 0.60 mequiv./g(dry) for potassium ions, 1.84 mequiv./g(dry) for magnesium ions, 1.08 mequiv./g(dry) for calcium ions and 1.36 mequiv./g(dry) for strontium ions. Its X-ray diffraction studies suggest that it is crystalline in nature. The material has been characterized by SEM, IR, TGA and DTG so as to identify the various functional groups and ion exchange sites present in this material. Quantum chemical computations at DFT/B3LYP/6-311G (d,p) level on model systems were performed to substantiate the structural conclusions based ion instrumental techniques. Investigations into the elution behaviour, ion exchange reversibility and distribution capacities of this material towards certain environmentally hazardous metal ions are also performed. The material shows good chemical stability towards acidic conditions and exhibits fast elution of exchangeable H(+) ions under neutral conditions. This material shows remarkable selectivity for Ni(II) and on the basis of its Kd value (4×10(2) in 0.01M HClO4) some binary separations of Ni(II) from other metal ions are performed.

  8. Fabrication of Li2TiO3 pebbles using PVA-boric acid reaction for solid breeding materials

    NASA Astrophysics Data System (ADS)

    Park, Yi-Hyun; Cho, Seungyon; Ahn, Mu-Young

    2014-12-01

    Lithium metatitanate (Li2TiO3) is a candidate breeding material of the Helium Cooled Ceramic Reflector (HCCR) Test Blanket Module (TBM). The breeding material is used in pebble-bed form to reduce the uncertainty of the interface thermal conductance. In this study, Li2TiO3 pebbles were successfully fabricated by the slurry droplet wetting method using the cross-linking reaction between polyvinyl alcohol (PVA) and boric acid. The effects of fabrication parameters on the shaping of Li2TiO3 green body were investigated. In addition, the basic characteristics of the sintered pebble were also evaluated. The shape of Li2TiO3 green bodies was affected by slurry viscosity, PVA content and boric acid content. The grain size and average crush load of sintered Li2TiO3 pebble were controlled by the sintering time. The boron was completely removed during the final sintering process.

  9. Highly-ordered layered organo-mineral materials prepared via reactions of n-alkylphosphonic acids with apatite.

    PubMed

    Gelfer, Mikhail Y; Burger, Christian; Hsiao, Benjamin S; D'Andrea, Susan C; Fadeev, Alexander Y

    2006-03-15

    This work describes a novel class of layered organo-mineral materials manufactured via a single-step solution-phase reaction of n-alkylphosphonic acids (CnH(2n+1)P(O)(OH)2) with calcium hydroxyapatite mineral (CaHAP). TEM, SAXS, WAXS, FTIR, and Vapor Phase Adsorption data suggest that these alkyl-CaHAP materials present a surface-modified CaHAP matrix coated with ordered layers of calcium alkylphosphonates that are strongly adhered to the surface. Interlayer spacing increases from 1.47 (C3-CaHAP) to 4.77 nm (C18-CaHAP). According to FTIR, ordering of alkyl chains improves with the alkyl chain length. The organic loads in these alkyl-CaHAP can be controlled over a wide range (up to approximately 60%) by varying alkyl chain and the concentration of alkylphosphonic acids in the solution.

  10. Proteomic and biochemical basis for enhanced growth yield of Enterobacter sp. LCR1 on insoluble phosphate medium.

    PubMed

    Kumar, Arvind; Rai, Lal Chand

    2015-01-01

    Proteomics and biochemical analyses were used to unravel the basis for higher growth yield of Enterobacter sp. LCR1 on insoluble phosphate medium compared to soluble. Proteomic analysis using 2-DE, MALDI-TOF/MS and LC-MS revealed the involvement of nine proteins. Down-regulation of fructose bisphosphate aldolase with decreased concentrations of glucose-6-phosphate and fructose-6-phosphate indicated diminished glycolysis. However, up-regulation of phosphoglycerate mutase, increase in the activities of 6-phosphogluconate dehydratase, 2-keto-3-deoxy-6-phosphogluconate aldolase and 6-phosphogluconate dehydrogenase suggested induction of Entner-Doudoroff and pentose phosphate pathways. These pathways generate sufficient energy from gluconic acid, which is also used for biosynthesis as indicated by up-regulation of elongation factor Tu, elongation factor G and protein disulfide isomerase. Increased reactive oxygen species (ROS) formation resulting from organic acid oxidation leads to overexpressed manganese superoxide dismutase and increased activities of catalase and ascorbate peroxidase. Thus the organism uses gluconate instead of glucose for energy, while alleviating extra ROS formation by oxidative defense enzymes.

  11. Behavior of transplutonium elements on ion-exchange materials in mixed aqueous-organic solutions of mineral acids

    SciTech Connect

    Guseva, L.I.; Tikhomirov, G.S.; Stepushkina, V.V.

    1987-03-01

    Systematic studies are reported on the behavior of transplutonium elements (TPE) on cation-exchange and anion-exchange materials in mixed aqueous-organic solutions of mineral acids (HClO/sub 4/, HCl, HNO/sub 3/, H/sub 2/SO/sub 4/, H/sub 3/PO/sub 4/) as affected by solution composition, nature of acid, and nature of organic solvent. With all these acids, replacing most of the water by alcohol increases the TPE uptake on the ion exchangers, and the effect occurs for the cation exchangers at lower contents of the organic component. Optimum conditions have been identified for concentrating and separating TPE from numerous elements. The most effective system consists of anion exchanger with HNO/sub 3/ and alcohol.

  12. [Effect of polymer material thermal destruction products on external respiration and acid-base status of blood].

    PubMed

    Tavolzhanova, T I; Rozova, K V

    2004-01-01

    In experiments on white laboratory rats the influence of fluor-, cyan- and sulfur-containing gaseous products, formed under thermodestruction of synthetic materials in normal and high environmental temperature on external respiration and some parameters of acid-base blood values was investigated. It was shown, that external respiration, due to considerable it depression, could not compensate neither hypoxic state, accompanied by hypoxemia, nor hypercapnia and acidosis, developed under the influence of toxic agents both in normal environmental temperature and in hyperthermia.

  13. Use of wastewater sludge as a raw material for production of L-lactic acid

    SciTech Connect

    Nakasaki, Kiyohiko; Akakura, Naoki; Adachi, Tomohiko; Akiyama, Tetsuo

    1999-01-01

    This study utilizes wastewater sludges to produce L-lactic acid, a precursor of biodegradable plastic. The high concentrations of cellulose contained in the sludge, derived from a paper manufacturing facility, have been found to be convertible to L-lactic acid at a rate as high as 6.91 g/L. To achieve such a high conversion rate, the sludge must be pretreated with cellulase. This pretreatment includes inoculation of the sludge with lactic acid bacteria, strain LA1, after the sludge has been subjected to enzymatic hydrolysis.

  14. A stable solid acid material: Sulfated ZrO2 dispersed on alumina nanotubes

    NASA Astrophysics Data System (ADS)

    Feng, Yu; Jiaqi, Chen; Xu, Wang; Rui-Feng, Li

    2017-02-01

    A tubular solid acid catalyst was designed by loading sulfated zirconia into γ-Al2O3 nanotubes using the method of stepwise deposition. The XRD, N2 adsorption-desorption characterization demonstrated that introducing alumina nanotube and SO4 2- anions have played an important role in stabilizing the metastable tetragonal ZrO2 phase, and the sulfated zirconia on the surface of the γ-Al2O3 nanotube has high dispersion and stability. The catalyst reused repeatedly possesses large amounts of acid sites and good acidity, exhibiting high catalytic activity and stability for isopropylbenzene cracking.

  15. Proteomic strategy for identifying mollusc shell proteins using mild chemical degradation and trypsin digestion of insoluble organic shell matrix: a pilot study on Haliotis tuberculata.

    PubMed

    Bédouet, Laurent; Marie, Arul; Berland, Sophie; Marie, Benjamin; Auzoux-Bordenave, Stéphanie; Marin, Frédéric; Milet, Christian

    2012-08-01

    A successful strategy for the identification of shell proteins is based on proteomic analyses where soluble and insoluble fractions isolated from organic shell matrix are digested with trypsin with the aim of generating peptides, which are used to identify novel shell proteins contained in databases. However, using trypsin as a sole degradative agent is limited by the enzyme's cleavage specificity and is dependent upon the occurrence of lysine and arginine in the shell protein sequence. To bypass this limitation, we investigated the ability of trifluoroacetic acid (TFA), a low-specificity chemical degradative agent, to generate clusters of analyzable peptides from organic shell matrix, suitable for database annotation. Acetic acid-insoluble fractions from Haliotis tuberculata shell were processed by trypsin followed by TFA digestion. The hydrolysates were used to annotate an expressed sequence tag library constructed from the mantle tissue of Haliotis asinina, a tropical abalone species. The characterization of sequences with repeat motifs featured in some of the shell matrix proteins benefited from TFA-induced serial cutting, which can result in peptide ladder series. Using the degradative specificities of TFA and trypsin, we were able to identify five novel shell proteins. This pilot study indicates that a mild chemical digestion of organic shell matrix combined with trypsin generates peptides suitable for proteomic analysis for better characterization of mollusc shell matrix proteins.

  16. Passive neutralization of acid mine drainage using basic oxygen furnace slag as neutralization material: experimental and modelling.

    PubMed

    Zvimba, John N; Siyakatshana, Njabulo; Mathye, Matlhodi

    2017-03-01

    This study investigated passive neutralization of acid mine drainage using basic oxygen furnace slag as neutralization material over 90 days, with monitoring of the parameters' quality and assessment of their removal kinetics. The quality was observed to significantly improve over time with most parameters removed from the influent during the first 10 days. In this regard, removal of acidity, Fe(II), Mn, Co, Ni and Zn was characterized by fast kinetics while removal kinetics for Mg and SO4(2-) were observed to proceed slowly. The fast removal kinetics of acidity was attributed to fast release of alkalinity from slag minerals under mildly acidic conditions of the influent water. The removal of acidity through generation of alkalinity from the passive treatment system was also observed to generally govern the removal of metallic parameters through hydroxide formation, with overall percentage removals of 88-100% achieved. The removal kinetics for SO4(2-) was modelled using two approaches, yielding rate constant values of 1.56 and 1.53 L/(day mol) respectively, thereby confirming authenticity of SO4(2-) removal kinetics experimental data. The study findings provide insights into better understanding of the potential use of slags and their limitations, particularly in mine closure, as part of addressing this challenge in South Africa.

  17. AFM studies of the crystallization and habit modification of an excipient material, adipic acid.

    PubMed

    Keel, T R; Thompson, C; Davies, M C; Tendler, S J B; Roberts, C J

    2004-08-06

    Atomic force microscopy (AFM) has been used to investigate the (1 0 0) face of crystalline adipic acid, both in air and liquid environments. In air, surface reorganization occurred during scanning of the AFM probe, which has been investigated using single point force-distance analysis under a controlled relative humidity (RH) environment. We suggest such reorganization can be attributed to the influence of a network of water molecules bound to the hydrophilic (1 0 0) surface permitting local AFM tip-enhanced dissolution and reorganization of the solute. In situ imaging was also carried out on the crystals, revealing etch-pit formation during dissolution, and rapid growth at higher levels of supersaturation (sigma), both of which are direct consequences of the hydrophilic nature of the (1 0 0) face. Also presented here are nanoscale observations of the effect of octanoic acid, a structurally-related habit modifier, on crystalline adipic acid. Using AFM, we have been able to show that the presence of octanoic acid at low concentration has little observable affect on the development of the (1 0 0) face; however, as this concentration is increased, there are clear changes in step morphology and growth mode on the (1 0 0) face of the crystal. At a concentration of 1.26 mmol dm(-3) (a concentration corresponding to a molar ratio of approximately 1:175 octanoic acid:adipic acid), growth on the (1 0 0) face is inhibited, with in situ AFM imaging indicating this is a direct consequence of octanoic acid binding to the surface, and pinning the monomolecular growth steps.

  18. Using Enviro-Pod low altitude imagery to inventory building surface materials for an acid rain study - A Baltimore example

    NASA Technical Reports Server (NTRS)

    Ellefsen, Richard; Coffland, Bruce

    1987-01-01

    Low altitude, oblique and vertical color photography taken from EPA's Enviro-Pod Ka 85 camera system has provided the data for taking an inventory of building surface materials in a test area of downtown Baltimore. Photography was acquired from a gridded flight plan to provide views of all sides of buildings. Color, texture, and linear detail are employed in the photo interpretation aided by contextual reference to a classification of building construction type developed in an earlier study. The work could potentially support a materials inventory initiated by the National Acid Precipitation Assessment Program (NAPAP) by scientists from EPA, Geological Survey, and the Department of Energy. Initial results show the method to be viable. Discrete surface materials such as brick, both bare and painted, stone, and metal are identified.

  19. Quaternized chitosan/κ-carrageenan/caffeic acid-coated poly(3-hydroxybutyrate) fibrous materials: Preparation, antibacterial and antioxidant activity.

    PubMed

    Ignatova, Milena; Manolova, Nevena; Rashkov, Iliya; Markova, Nadya

    2016-11-20

    Novel fibrous materials with antioxidant and antibacterial properties from poly(3-hydroxybutyrate) (PHB), quaternized chitosan (QCh), κ-carrageenan (Car) and caffeic acid (CA) were obtained. These materials were prepared by applying electrospinning or electrospinning in conjunction with dip-coating and polyelectrolyte complex (PEC) formation. It was found that the CA release depended on the fiber composition. X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC) revealed that CA incorporated in the fibers was in the amorphous state, whereas CA included in the coating was in the crystalline state. In contrast to the neat PHB mats, the CA-containing mats and the PEC QCh/Car-coated mats were found to kill the Gram-positive bacteria S. aureus and the Gram-negative bacteria E. coli and were effective in suppressing the adhesion of pathogenic bacteria S. aureus. Enhancement of the antioxidant activity of the fibrous materials containing both CA and QCh/Car coating was observed.

  20. Determination of Perfluorinated Alkyl Acid Concentrations in Biological Standard Reference Materials

    EPA Science Inventory

    Standard reference materials (SRMs) are homogeneous, well-characterized materials used to validate measurements and improve the quality of analytical data. The National Institute of Standards and Technology (NIST) has a wide range of SRMs that have mass fraction values assigned ...

  1. Organic materials retain high proportion of protons, iron and aluminium from acid sulphate soil drainage water with little subsequent release.

    PubMed

    Dang, Tan; Mosley, Luke M; Fitzpatrick, Rob; Marschner, Petra

    2016-12-01

    When previously oxidised acid sulphate soils are leached, they can release large amounts of protons and metals, which threaten the surrounding environment. To minimise the impact of the acidic leachate, protons and metals have to be retained before the drainage water reaches surrounding waterways. One possible amelioration strategy is to pass drainage water through permeable reactive barriers. The suitability of organic materials for such barriers was tested. Eight organic materials including two plant residues, compost and five biochars differing in feedstock and production temperature were finely ground and filled into PVC cores at 3.5 g dry wt/core. Field-collected acidic drainage water (pH 3, Al 22 mg L(-1) and Fe 48 mg L(-1)) was applied in six leaching events followed by six leaching events with reverse osmosis (RO) water (45 mL/event). Compost and biochars increased the leachate pH by up to 4.5 units and had a high retention capacity for metals. The metal and proton release during subsequent leaching with RO water was very small, cumulatively only 0.05-0.8 % of retained metals and protons. Retention was lower in the two plant residues, particularly wheat straw, which raised leachate pH by 2 units only in the first leaching event with drainage water, but had little effect on leachate pH in the following leaching events. It can be concluded that organic materials and particularly biochars and compost have the potential to be used in acid drainage treatment to remove and retain protons and metals.

  2. Fate of the naturally occurring radioactive materials during treatment of acid mine drainage with coal fly ash and aluminium hydroxide.

    PubMed

    Madzivire, Godfrey; Maleka, Peane P; Vadapalli, Viswanath R K; Gitari, Wilson M; Lindsay, Robert; Petrik, Leslie F

    2014-01-15

    Mining of coal is very extensive and coal is mainly used to produce electricity. Coal power stations generate huge amounts of coal fly ash of which a small amount is used in the construction industry. Mining exposes pyrite containing rocks to H2O and O2. This results in the oxidation of FeS2 to form H2SO4. The acidic water, often termed acid mine drainage (AMD), causes dissolution of potentially toxic elements such as, Fe, Al, Mn and naturally occurring radioactive materials such as U and Th from the associated bedrock. This results in an outflow of AMD with high concentrations of sulphate ions, Fe, Al, Mn and naturally occurring radioactive materials. Treatment of AMD with coal fly ash has shown that good quality water can be produced which is suitable for irrigation purposes. Most of the potentially toxic elements (Fe, Al, Mn, etc) and substantial amounts of sulphate ions are removed during treatment with coal fly ash. This research endeavours to establish the fate of the radioactive materials in mine water with coal fly ash containing radioactive materials. It was established that coal fly ash treatment method was capable of removing radioactive materials from mine water to within the target water quality range for drinking water standards. The alpha and beta radioactivity of the mine water was reduced by 88% and 75% respectively. The reduced radioactivity in the mine water was due to greater than 90% removal of U and Th radioactive materials from the mine water after treatment with coal fly ash as ThO2 and UO2. No radioisotopes were found to leach from the coal fly ash into the mine water.

  3. Efficacy and tolerance of insoluble carob fraction in the treatment of travellers' diarrhoea.

    PubMed

    Hostettler, M; Steffen, R; Tschopp, A

    1995-09-01

    The water-insoluble carob fraction (fraction insoluble caroube, FIC, Nestlé) has been successfully used in the treatment of infantile diarrhoea. To investigate the efficacy and toxicity of FIC (1970 mg to be taken every 2 hours over a 48-hour period except during sleeping time) in the treatment of travellers' diarrhoea in adults, a double-blind, computer randomized, placebo-controlled study was conducted. Of the 755 volunteers recruited at the Zurich University Vaccination Centre, 628 (83.5%) returned their questionnaires. Among them, 164 (27.7%) had diarrhoea, but only 69 (42%) used the trial medication correctly; the others were rated non-complaint. No significant difference in efficacy (p = 0.12) or adverse effects were observed in the two study groups. In conclusion, FIC, although showed a positive trend, was not efficacious.

  4. Wetting and hydration of insoluble soot particles in the upper troposphere.

    PubMed

    Persiantseva, N M; Popovicheva, O B; Shonija, N K

    2004-12-01

    Wettability and hydration are determined for aircraft combustor and laboratory-made soots which are used as surrogates for the insoluble part of aircraft-generated black carbon particles in the upper troposphere (UT). The measured water/ice contact angles on the soot surfaces are in the range 60-80 degrees. Factors influencing the soot wetting show a tremendous dependence on the surface chemical composition and microstructure. Wetting characteristics of soots are directly related to its hydrophilicity. The inverse Kelvin effect is considered as a mechanism of ice nucleation which is facilitated by the soot agglomerated structure with interparticle cavities in which condensation takes place on the insoluble surface with a high water contact angle. Estimations of the critical supersaturations needed for the ice condensation growth of particles are provided to determine which of the wetting characteristics are required for cirrus cloud formation in ice saturated regions of the UT.

  5. Cloning of a Streptococcus mutans glucosyltransferase gene coding for insoluble glucan synthesis.

    PubMed Central

    Aoki, H; Shiroza, T; Hayakawa, M; Sato, S; Kuramitsu, H K

    1986-01-01

    The gtfB gene coding for a glucosyltransferase (GTF) activity of Streptococcus mutans GS-5 was isolated on a 15.4-kilobase DNA fragment by using a lambda L47.1 gene library. The activity was catalyzed by gene products of 150 and 145 kilodaltons which reacted with antibodies directed against both soluble and insoluble glucan-synthesizing GTFs. The enzyme present in crude Escherichia coli extracts synthesized both soluble and insoluble glucans. The enzyme was partially purified from lysates of the lambda DS-76 clone and synthesized both types of glucans in a primer-independent fashion. In addition, the purified enzyme exhibited a pI of approximately 5.0. Southern blot analysis indicated that the cloned GTF gene represented a contiguous nucleotide sequence on the strain GS-5 chromosome. Furthermore, evidence for the existence of a distinct gene sharing partial homology with gtfB was also obtained. The gtfB gene was subcloned into plasmid pACYC184 into E. coli and exhibited GTF activity when carried on GS-5 inserts as small as 5 kilobases. The approximate location of the GTF promoter and the direction of gene transcription were also determined. The cloned enzyme was not secreted through the cytoplasmic membrane of E. coli, since most of the activity was found in the cytoplasm and, in lesser amounts, associated with the cytoplasmic membrane. The gtfB gene was insertionally inactivated by introducing a gene fragment coding for erythromycin resistance into the GTF coding region. After transformation of strain GS-5 with the altered gene, transformants defective in insoluble glucan synthesis were identified. These results indicate that the gtfB gene codes for a GTF involved in insoluble glucan synthesis in strain GS-5. Images PMID:3017865

  6. An immunostimulating water insoluble β-glucan of an edible hybrid mushroom: isolation and characterization.

    PubMed

    Maity, Kousik; Samanta, Surajit; Bhanja, Sunil K; Maity, Saikat; Sen, Ipsita K; Maiti, Swatilekha; Behera, Birendra; Maiti, Tapas K; Sikdar, Samir R; Islam, Syed S

    2013-01-01

    An immunostimulating water-insoluble β-glucan isolated from hot alkaline extract of the fruiting bodies of an edible somatic hybrid mushroom of Pleurotus florida and Calocybe indica var. APK2 showed significant macrophage, splenocyte, and thymocyte activations. On the basis of total hydrolysis, methylation analysis, and NMR experiments ((1)H, (13)C, DQF-COSY, TOCSY, NOESY, DEPT-135, and HSQC), the repeating unit of the polysaccharide is established.

  7. Parameterization of cloud droplet formation for global and regional models: including adsorption activation from insoluble CCN

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Sokolik, I. N.; Nenes, A.

    2008-09-01

    Dust and black carbon aerosol have long been known to have potentially important and diverse impacts on cloud droplet formation. Most studies to date focus on the soluble fraction of such particles, and ignore interactions of the insoluble fraction with water vapor (even if known to be hydrophilic). To address this gap, we develop a new parameterization framework that considers cloud droplet formation within an ascending air parcel containing insoluble (but wettable) particles mixed with aerosol containing an appreciable soluble fraction. Activation of particles with a soluble fraction is described through well-established Köhler Theory, while the activation of hydrophilic insoluble particles is treated by "adsorption-activation" theory. In the latter, water vapor is adsorbed onto insoluble particles, the activity of which is described by a multilayer Frankel-Halsey-Hill (FHH) adsorption isotherm modified to account for particle curvature. We further develop FHH activation theory, and i) find combinations of the adsorption parameters AFHH, BFHH for which activation into cloud droplets is not possible, and, ii) express activation properties (critical supersaturation) that follow a simple power law with respect to dry particle diameter. Parameterization formulations are developed for sectional and lognormal aerosol size distribution functions. The new parameterization is tested by comparing the parameterized cloud droplet number concentration against predictions with a detailed numerical cloud model, considering a wide range of particle populations, cloud updraft conditions, water vapor condensation coefficient and FHH adsorption isotherm characteristics. The agreement between parameterization and parcel model is excellent, with an average error of 10% and R2 ~0.98.

  8. Parameterization of cloud droplet formation for global and regional models: including adsorption activation from insoluble CCN

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Sokolik, I. N.; Nenes, A.

    2009-04-01

    Dust and black carbon aerosol have long been known to exert potentially important and diverse impacts on cloud droplet formation. Most studies to date focus on the soluble fraction of these particles, and overlook interactions of the insoluble fraction with water vapor (even if known to be hydrophilic). To address this gap, we developed a new parameterization that considers cloud droplet formation within an ascending air parcel containing insoluble (but wettable) particles externally mixed with aerosol containing an appreciable soluble fraction. Activation of particles with a soluble fraction is described through well-established Köhler theory, while the activation of hydrophilic insoluble particles is treated by "adsorption-activation" theory. In the latter, water vapor is adsorbed onto insoluble particles, the activity of which is described by a multilayer Frenkel-Halsey-Hill (FHH) adsorption isotherm modified to account for particle curvature. We further develop FHH activation theory to i) find combinations of the adsorption parameters AFHH, BFHH which yield atmospherically-relevant behavior, and, ii) express activation properties (critical supersaturation) that follow a simple power law with respect to dry particle diameter. The new parameterization is tested by comparing the parameterized cloud droplet number concentration against predictions with a detailed numerical cloud model, considering a wide range of particle populations, cloud updraft conditions, water vapor condensation coefficient and FHH adsorption isotherm characteristics. The agreement between parameterization and parcel model is excellent, with an average error of 10% and R2~0.98. A preliminary sensitivity study suggests that the sublinear response of droplet number to Köhler particle concentration is not as strong for FHH particles.

  9. Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942)

    SciTech Connect

    Lu Swan, Delta Ferrites LLC

    2009-09-30

    A new process for manufacturing an enriched, iron-based product (strontium hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to develop and demonstrate (via pilot scale testing and partial-capacity production trials) the viability of a patented method to produce strontium-based compounds that, when mixed with steel pickling acid and roasted, would result in a strontium hexaferrite powder precursor which could then be subjected to further heat treatment in an atmosphere that promotes rapid, relatively low-temperature formation of discrete strontium hexaferrite magnetic domains yielding an enriched iron-based product, strontium hexaferrite, that can be used in manufacturing hard ferrite magnets.

  10. Reversible collapse of insoluble monolayers: new insights on the influence of the anisotropic line tension of the domain.

    PubMed

    González-Delgado, Antonio M; Pérez-Morales, Marta; Giner-Casares, Juan J; Muñoz, Eulogia; Martín-Romero, María T; Camacho, Luis

    2009-10-08

    In this paper, we study the collapse of a mixed insoluble monolayer formed by a cationic matrix, dioctadecyl-dimethylammonium bromide (DOMA), and a tetra-anionic porphyrin, tetrakis(4-sulfonatophenyl)porphyrin (TSPP), in a molar ratio TSPP/DOMA = 1:4. During the collapse of this system, we visualized the formation of circular domains consisting exclusively of trilayer, although the domains coalescence was not observed. The coexistence of trilayer and monolayer at the final step of the collapse cannot be interpreted exclusively in terms of a thermodynamic phase equilibrium, intervening as an additional factor the anisotropic line tension of the domain. A high line tension implies a high resistance to the domain deformation, and the anisotropy of the line tension implies the lack of coalescence between these domains, which has been experimentally observed by Brewster angle microscopy for us. Under these circumstances, the domains of collapsed material could enclose monolayer regions where the local surface pressure drops thus stopping the collapse process. The collapse of the TSPP/DOMA system is reversible, that is, the return of the three-dimensional material to the monolayer fits into a simple kinetics according to the nucleation-growth-collision theory. As for the collapse, the reverse process is also affected by the line tension of the domains. This paper relates the high line tension and the anisotropic line tension of a given domains with the reversible nature of the collapse process.

  11. Production of hydrogen and volatile fatty acid by Enterobacter sp. T4384 using organic waste materials.

    PubMed

    Kim, Byung-Chun; Deshpande, Tushar R; Chun, Jongsik; Yi, Sung Chul; Kim, Hyunook; Um, Youngsoon; Sang, Byoung-In

    2013-02-01

    In a study of hydrogen-producing bacteria, strain T4384 was isolated from rice field samples in the Republic of Korea. The isolate was identified as Enterobacter sp. T4384 by phylogenetic analysis of 16S rRNA and rpoB gene sequences. Enterobacter sp. T4384 grew at a temperature range of 10-45 degrees C and at an initial pH range of 4.5-9.5. Strain T4384 produced hydrogen at 0-6% NaCl by using glucose, fructose, and mannose. In serum bottle cultures using a complete medium, Enterobacter sp. T4384 produced 1,098 ml/l H2, 4.0 g/l ethanol, and 1.0 g/l acetic acid. In a pH-regulated jar fermenter culture with the biogas removed, 2,202 ml/l H2, 6.2 g/l ethanol, and 1.0 g/l acetic acid were produced, and the lag-phase time was 4.8 h. Strain T4384 metabolized the hydrolysate of organic waste for the production of hydrogen and volatile fatty acid. The strain T4384 produced 947 ml/l H2, 3.2 g/l ethanol, and 0.2 g/l acetic acid from 6% (w/v) food waste hydrolysate; 738 ml/l H2, 4.2 g/l ethanol, and 0.8 g/l acetic acid from Miscanthus sinensis hydrolysate; and 805 ml/l H2, 5.0 g/l ethanol, and 0.7 g/l acetic acid from Sorghum bicolor hydrolysate.

  12. Investigation of Rheological Impacts on Sludge Batch 3 as Insoluble Solids and Wash Endpoints are Adjusted

    SciTech Connect

    Fellinger, T. L.

    2005-07-12

    The Defense Waste Processing Facility (DWPF) is currently processing and immobilizing radioactive sludge slurry into a durable borosilicate glass. The DWPF has already processed three sludge batches (Sludge Batch 1A, Sludge Batch 1B, and Sludge Batch 2) and is currently processing the fourth sludge batch (Sludge Batch 3). A sludge batch is defined as a single tank of sludge slurry or a combination of sludge slurries from different tanks that has been or will be qualified before being transferred to DWPF. As a part of the Sludge Batch 3 (SB3) qualification task, rheology measurements of the sludge slurry were requested at different insoluble solids loadings. These measurements were requested in order to gain insight into potential processing problems that may occur as the insoluble solids are adjusted up or down (by concentration or dilution) during the process. As a part of this study, a portion of the ''as received'' SB3 sample was washed with inhibited water (0.015 M NaOH and 0.015 M NaNO2) to target 0.5M Na versus a measured 1M Na in the supernate. The purpose of the ''washing'' step was to allow a comparison of the SB3 rheological data to the rheological data collected for Sludge Batch 2 (SB2) and to determine if there was a dependence of the yield stress and consistency as a function of washing. The ''as received'' SB3 rheology data was also compared to SB3 simulants prepared by the Simulant Development Program in order to provide guidance for selecting a simulant that is more representative of the rheological properties of the radioactive sludge slurry. A summary of the observations, conclusions are: (1) The yield stress and plastic viscosity increased as the weight percent insoluble solids were increased for the ''as received'' and ''washed'' SB3 samples, at a fixed pH. (2) For the same insoluble solids loading, the yield stress for the SB2 sample is approximately a factor of three higher than the ''as received'' SB3 sample. There also appears to be small

  13. Effect of homogenization and ultrasonication on the physical properties of insoluble wheat bran fibres

    NASA Astrophysics Data System (ADS)

    Hu, Ran; Zhang, Min; Adhikari, Benu; Liu, Yaping

    2015-10-01

    Wheat bran is rich in dietary fibre and its annual output is abundant, but underutilized. Insoluble dietary fibre often influences food quality negatively; therefore, how to improve the physical and chemical properties of insoluble dietary fibre of wheat bran for post processing is a challenge. Insoluble dietary fibre was obtained from wheat bran and micronized using high-pressure homogenization, high-intensity sonication, and a combination of these two methods. The high-pressure homogenization and high-pressure homogenization+high-intensity sonication treatments significantly (p<0.05) improved the solubility, swelling, water-holding, oil-holding, and cation exchange capacities. The improvement of the above properties by high-intensity sonication alone was marginal. In most cases, the high-pressure homogenization process was as good as the high-pressure homogenization+high-intensity sonication process in improving the above-mentioned properties; hence, the contribution of high-`intensity sonication in the high-pressure homogenization+high-intensity sonication process was minimal. The best results show that the minimum particle size of wheat bran can reach 9 μm, and the solubility, swelling, water-holding, oil-holding, cation exchange capacities change significantly.

  14. Insoluble drug delivery strategies: review of recent advances and business prospects

    PubMed Central

    Kalepu, Sandeep; Nekkanti, Vijaykumar

    2015-01-01

    The emerging trends in the combinatorial chemistry and drug design have led to the development of drug candidates with greater lipophilicity, high molecular weight and poor water solubility. Majority of the failures in new drug development have been attributed to poor water solubility of the drug. Issues associated with poor solubility can lead to low bioavailability resulting in suboptimal drug delivery. About 40% of drugs with market approval and nearly 90% of molecules in the discovery pipeline are poorly water-soluble. With the advent of various insoluble drug delivery technologies, the challenge to formulate poorly water soluble drugs could be achieved. Numerous drugs associated with poor solubility and low bioavailabilities have been formulated into successful drug products. Several marketed drugs were reformulated to improve efficacy, safety and patient compliance. In order to gain marketing exclusivity and patent protection for such products, revitalization of poorly soluble drugs using insoluble drug delivery technologies have been successfully adopted by many pharmaceutical companies. This review covers the recent advances in the field of insoluble drug delivery and business prospects. PMID:26579474

  15. Insoluble drug delivery strategies: review of recent advances and business prospects.

    PubMed

    Kalepu, Sandeep; Nekkanti, Vijaykumar

    2015-09-01

    The emerging trends in the combinatorial chemistry and drug design have led to the development of drug candidates with greater lipophilicity, high molecular weight and poor water solubility. Majority of the failures in new drug development have been attributed to poor water solubility of the drug. Issues associated with poor solubility can lead to low bioavailability resulting in suboptimal drug delivery. About 40% of drugs with market approval and nearly 90% of molecules in the discovery pipeline are poorly water-soluble. With the advent of various insoluble drug delivery technologies, the challenge to formulate poorly water soluble drugs could be achieved. Numerous drugs associated with poor solubility and low bioavailabilities have been formulated into successful drug products. Several marketed drugs were reformulated to improve efficacy, safety and patient compliance. In order to gain marketing exclusivity and patent protection for such products, revitalization of poorly soluble drugs using insoluble drug delivery technologies have been successfully adopted by many pharmaceutical companies. This review covers the recent advances in the field of insoluble drug delivery and business prospects.

  16. Glucose content in the liquid hydrolysate after dilute acid pretreatment is affected by the starch content in rice straw.

    PubMed

    Teramura, Hiroshi; Oshima, Tomoko; Matsuda, Fumio; Sasaki, Kengo; Ogino, Chiaki; Yamasaki, Masanori; Kondo, Akihiko

    2013-12-01

    Lignocellulosic biomass, such as rice straw, is often utilized as a bioresource after being hydrolyzed using dilute acid and separated into liquid hydrolysate and acid-insoluble residue. However, the biomass component that determines the distribution between liquid hydrolysate and acid-insoluble residue has not yet been clarified. In this study, the glucose content in the liquid hydrolysate and weight of acid-insoluble residue of 13 rice cultivars were analyzed. Starch content was positively correlated with glucose content in the liquid hydrolysate, and negatively correlated with acid-insoluble residue weight. These results indicate that the glucose in the liquid hydrolysate is mainly liberated from starch rather than cellulose in the rice straw. These observations suggest that starch content is a good indicator of the glucose distribution between the liquid hydrolysate and insoluble residue.

  17. The chaotrope-soluble glycoprotein GP1 is a constituent of the insoluble glycoprotein framework of the Chlamydomonas cell wall.

    PubMed

    Voigt, Jürgen; Frank, Ronald; Wöstemeyer, Johannes

    2009-02-01

    Chlamydomonas reinhardtii wild-type cells are surrounded by the insoluble cell wall component, a sac-like framework of cross-linked glycoproteins containing 22% hydroxyproline. The chaotrope-soluble cell wall glycoprotein GP1 is the only polypeptide with an even higher proportion of hydroxyproline (35%) occurring in vegetative C. reinhardtii cells. Mass spectrometric analyses of peptides released from the purified insoluble cell wall fraction by trypsin treatment and epitope analyses of polyclonal antibodies raised against different deglycosylation products of this particular wall fraction using 181 chemically synthesized GP1-derived pentadecapeptides revealed evidence that GP1 is indeed a constituent of the insoluble wall component.

  18. Synthesis of homoveratric acid-imprinted polymers and their evaluation as selective separation materials.

    PubMed

    Dana, Mariusz; Luliński, Piotr; Maciejewska, Dorota

    2011-05-05

    A bulk polymerization method was used to easily and efficiently prepare homoveratric acid (3,4-dimethoxyphenylacetic acid)-imprinted polymers from eight basic monomers: 2-vinylpyridine, 4-vinylpyridine, 1-vinylimidazole, N-allylaniline, N-allylpiperazine, allylurea, allylthiourea, and allylamine, in the presence of homoveratric acid as a template in N,N-dimethylformamide as a porogen. The imprinted polymer prepared from allylamine had the highest affinity to the template, showing an imprinting factor of 3.43, and allylamine polymers MIP8/NIP8 were selected for further studies. Their binding properties were analyzed using the Scatchard method. The results showed that the imprinted polymers have two classes of heterogeneous binding sites characterized by two pairs of K(d), B(max) values: K(d)(1) = 0.060 μmol/mL, B(max)(1) = 0.093 μmol/mg for the higher affinity binding sites, and K(d)(2) = 0.455 μmol/mL, B(max)(2) = 0.248 μmol/mg for the lower affinity binding sites. Non-imprinted polymer has only one class of binding site, with K(d) = 0.417 μmol/mL and B(max) = 0.184 μmol/mg. A computational analysis of the energies of the prepolymerization complexes was in agreement with the experimental results. It showed that the selective binding interactions arose from cooperative three point interactions between the carboxylic acid and the two methoxy groups in the template and amino groups in the polymer cavities. Those results were confirmed by the recognition studies performed with the set of structurally related compounds. Allylamine polymer MIP8 had no affinity towards biogenic amines. The obtained imprinted polymer could be used for selective separation of homoveratric acid.

  19. Evaluation of educational materials from a social marketing campaign to promote folic acid use among Hispanic women: insight from Cuban and Puerto Rican ethnic subgroups.

    PubMed

    Quinn, Gwendolyn P; Thomas, Kamilah B; Hauser, Kimberlea; Rodríguez, Nydia Y; Rodriguez-Snapp, Nazach

    2009-10-01

    Current data indicate significant disparities in awareness and use of folic acid between Hispanic and non-Hispanic women. Hispanic women are less likely to have heard about folic acid, to know that folic acid can prevent birth defects, to take folic acid daily, and to take folic acid before pregnancy. "Three Sisters/Las Tres Hermanos" is a folic acid social marketing campaign designed for Mexican-American women. To determine the effectiveness of the materials on other Hispanic sub groups, women of childbearing age from Cuba and Puerto Rico were recruited to evaluate the materials. Participants were asked five pre-test questions about folic acid knowledge and were then provided with the folic acid educational materials that included either a photo-novella and a low literacy brochure, or a video-novella in English or Spanish. Once the participants reviewed the materials, they were asked 10 post-test questions about the materials. The results of the evaluation are discussed.

  20. Water adsorption and cloud condensation nuclei activity of calcite and calcite coated with model humic and fulvic acids

    NASA Astrophysics Data System (ADS)

    Hatch, Courtney D.; Gierlus, Kelly M.; Schuttlefield, Jennifer D.; Grassian, Vicki H.

    Recent studies have shown that organics can alter the water adsorption and cloud condensation nuclei (CCN) activity of common deliquescent species in the Earth's atmosphere. However, very little is known about the effect of organics on water adsorption and CCN activity of insoluble nuclei, such as mineral dust aerosol. A large fraction of unidentified organic material in aerosol particles is composed of poly-acidic compounds resembling humic substances. The presence of these humic-like substances (HULIS) can alter the water adsorption and CCN activity of mineral dust aerosol. We have measured the CCN activity of model humic and fulvic acids and of mineral dust particles coated with these substances in the laboratory. We find that coatings of humic and fulvic acids on calcite particles significantly increases water adsorption compared to uncoated particles. CCN measurements indicate that humic- or fulvic acid-coated calcite particles are more CCN active than uncoated calcite particles. Additionally, thicker coatings of humic or fulvic acids appear to result in more efficient CCN activity. Thus, mineral dust particles coated with high molecular weight organic materials will take up more water and become more efficient CCN in the atmosphere than uncoated mineral dust particles, potentially altering the effect of mineral dust on the Earth's climate. In addition to the experimental results, we have explored a newly modified Köhler theory for predicting the CCN activity of insoluble, wettable particles based on multi layer water adsorption measurements of calcite.

  1. Inoculation of Pichia kudriavzevii RB1 degrades the organic acids present in raw compost material and accelerates composting.

    PubMed

    Nakasaki, Kiyohiko; Araya, Shogo; Mimoto, Hiroshi

    2013-09-01

    In this study, the yeast strain Pichia kudriavzevii RB1 was used as an inoculum to accelerate organic matter degradation of rabbit food with added organic acids, which was used as a model food waste for composting. The RB1 strain rapidly degraded the organic acids present in the raw compost material, leading to an increase in pH beyond the neutral level, within 2 days. Both mesophilic and thermophilic bacteria proliferated faster in the compost with RB1 inoculation than in that without inoculation. Although the yeast died with the increase in compost temperature, it affected the early stages of composting prior to the thermophilic stage and accelerated the composting process by 2 days by eliminating the initial lag phase seen in the growth of other microorganisms. Moreover, populations of Bacillus thermoamylovorans, Bacillus foraminis, and Bacillus coagulans became dominant during the thermophilic stages of both composting with and without RB1 inoculation.

  2. Synthesis and characterization of an insoluble polymer based on polyamidoamine: applications for the decontamination of metals in aqueous systems.

    PubMed

    Valdés, Oscar; Vergara, Claudia E; Camarada, Maria B; Carrasco-Sánchez, Veronica; Nachtigall, Fabiane M; Tapia, Jaime; Fischer, Rainer; González-Nilo, F D; Santos, Leonardo S

    2015-01-01

    We present a novel, insoluble, low-generation polyamidoamine (PAMAM)-based polymer. The monomer and polymer were characterized by fourier transform infrared spectroscopy, electrospray ionization mass spectrometry and thermogravimetric measurement, revealing that G0 acryloyl-terminated PAMAM were synthesized and polymerized using ammonium persulfate as an initiator, producing a high-density PAMAM derivative (PAMAM-HD). PAMAM-HD was tested for its ability to remove Na(I), K(I), Ca(II), Mg(II), Cu(II), Mn(II), Cd(II), Pb(II) and Zn(II) ions from acidic, neutral and basic aqueous solutions. PAMAM-HD efficiently removed metals ions from all three solutions. The greatest absorption efficiency at neutral pH was observed against Cu(II), Cd(II) and Pb(II), and the experimental data were supported by the calculated Kd values. Our data could have a significant impact on water purification by providing an inexpensive and efficient polymer for the removal of metal ions.

  3. Development of Lentivirus-Based Reference Materials for Ebola Virus Nucleic Acid Amplification Technology-Based Assays.

    PubMed

    Mattiuzzo, Giada; Ashall, James; Doris, Kathryn S; MacLellan-Gibson, Kirsty; Nicolson, Carolyn; Wilkinson, Dianna E; Harvey, Ruth; Almond, Neil; Anderson, Robert; Efstathiou, Stacey; Minor, Philip D; Page, Mark

    2015-01-01

    The 2013-present Ebola virus outbreak in Western Africa has prompted the production of many diagnostic assays, mostly based on nucleic acid amplification technologies (NAT). The calibration and performance assessment of established assays and those under evaluation requires reference materials that can be used in parallel with the clinical sample to standardise or control for every step of the procedure, from extraction to the final qualitative/quantitative result. We have developed safe and stable Ebola virus RNA reference materials by encapsidating anti sense viral RNA into HIV-1-like particles. The lentiviral particles are replication-deficient and non-infectious due to the lack of HIV-1 genes and Envelope protein. Ebola virus genes were subcloned for encapsidation into two lentiviral preparations, one containing NP-VP35-GP and the other VP40 and L RNA. Each reference material was formulated as a high-titre standard for use as a calibrator for secondary or internal standards, and a 10,000-fold lower titre preparation to serve as an in-run control. The preparations have been freeze-dried to maximise stability. These HIV-Ebola virus RNA reference materials were suitable for use with in-house and commercial quantitative RT-PCR assays and with digital RT-PCR. The HIV-Ebola virus RNA reference materials are stable at up to 37°C for two weeks, allowing the shipment of the material worldwide at ambient temperature. These results support further evaluation of the HIV-Ebola virus RNA reference materials as part of an International collaborative study for the establishment of the 1st International Standard for Ebola virus RNA.

  4. Synthesis, Characterization, and Environmental Applications of Hybrid Materials Based on Humic Acid Obtained by the Sol-Gel Route.

    PubMed

    Oliveira, Lílian Karla de; Molina, Eduardo Ferreira; Moura, André L A; de Faria, Emerson Henrique; Ciuffi, Katia Jorge

    2016-01-20

    Humic acids (HAs) are ubiquitous macromolecules in the environment. Due to their high contents of oxygenated functional groups, they can interact with contaminants present in the natural environment and therefore influence the behavior of pollutants. However, a pH of 2 or lower is required to maintain HAs in the solid form. To increase the stability of HAs and their capacity to bind to contaminants, this work proposes the development of new hybrid materials based on alkoxysilanes and HAs for environmental applications such as dye adsorption. Three different materials with new functional groups were prepared by employing the following alkoxysilanes: tetraethyl orthosilicate, (3-aminopropyl)triethoxysilane, and N-[3-(trimethoxylsilyl)propyl]ethylenediamine. The final materials were denoted HWA, HOA, and HTA, respectively, and they were characterized by elemental analysis, diffuse reflectance Fourier-transform infrared spectroscopy (DRIFT), small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM), and N2 gas-volumetric adsorption. The point of zero charge (pzc) and stability of these materials were also determined. Their selectivity was evaluated in adsorption experiments performed with two different charged dyes in aqueous medium, namely anionic rose bengal (RB) and cationic methylene blue (MB). The elemental, DRIFT, SAXS, SEM, and textural analyses confirmed the presence of a combination of the features of HAs and alkoxysilanes. The pzc results showed that the new materials displayed different characteristics and affinities. All the materials were stable in aqueous solution up to pH 10. For MB, the percentage removal values obtained by using HWA, HOA, and HTA were 98, 85, and 67%, respectively. As for RB, the percentage removal values were 19, 18, and 44% for HWA, HOA, and HTA, respectively. These hybrid materials have potential use as adsorbents for the removal of cationic or anionic species and could be viable alternatives to remove various

  5. Lipoic Acid Gold Nanoparticles Functionalized with Organic Compounds as Bioactive Materials

    PubMed Central

    Turcu, Ioana; Zarafu, Irina; Popa, Marcela; Chifiriuc, Mariana Carmen; Bleotu, Coralia; Culita, Daniela; Ghica, Corneliu; Ionita, Petre

    2017-01-01

    Water soluble gold nanoparticles protected by lipoic acid were obtained and further functionalized by standard coupling reaction with 1-naphtylamine, 4-aminoantipyrine, and 4′-aminobenzo-15-crown-5 ether. Derivatives of lipoic acid with 1-naphtylamine, 4-aminoantipyrine, and 4′-aminobenzo-15-crown-5 ether were also obtained and characterized. All these were tested for their antimicrobial activity, as well as for their influence on mammalian cell viability and cellular cycle. In all cases a decreased antimicrobial activity of the obtained bioactive nanoparticles was observed as compared with the organic compounds, proving that a possible inactivation of the bioactive groups could occur during functionalization. However, both the gold nanoparticles as well as the functionalized bioactive nanosystems proved to be biocompatible at concentrations lower than 50 µg/mL, as revealed by the cellular viability and cell cycle assay, demonstrating their potential for the development of novel antimicrobial agents. PMID:28336877

  6. Use of amino acid-based polymeric material for isolation of a protein from poison

    NASA Astrophysics Data System (ADS)

    Erol, Kadir; Köse, Kazım; Güngüneş, Hakan; Köse, Dursun Ali

    2017-02-01

    Melittin is a small protein with 126 amino acid residues which exists in the bee and snake venom. In this study, the Fe(II)-Ni(II) double-salt incorporated poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-aspartic acid), poly(HEMA-MAsp), magnetic microparticles were synthesized for the separation of melittin. Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer and Mossbauer spectroscopy techniques were used for the characterization. The melittin adsorption capacity of magnetic microparticles in aqueous solution were identified as 69.60 mg/g, whereas that in real be venom solution was 46.80 mg/g microparticle. The adsorption-desorption cycle was repeated 5 times and no significant decrease were observed in the adsorption capacity.

  7. Method for the extraction of the volatile compound salicylic acid from tobacco leaf material.

    PubMed

    Verberne, Marianne C; Brouwer, Nynke; Delbianco, Federica; Linthorst, Huub J M; Bol, John F; Verpoorte, Robert

    2002-01-01

    Salicylic acid (SA) is a signalling compound in plants which is able to induce systemic acquired resistance. In the analysis of SA in plant tissues, the extraction recovery is often very low and variable. This is mainly caused by sublimation of SA, especially during evaporation of organic solvents. Techniques have been designed in order to overcome this problem. In the first part of the extraction procedure, sublimation of SA was prevented by addition of 0.2 M sodium hydroxide. At a later stage of the extraction procedure, sublimation of SA during solvent evaporation was controlled by the addition of a small amount of HPLC eluent. In this way, recoveries in the range of 71-91% for free SA and 65-79% for acid-hydrolysed SA were obtained. Recoveries could be further optimised by the use of an internal standard to correct for volume changes after the addition of the HPLC eluent.

  8. Methods and materials for the production of L-lactic acid in yeast

    DOEpatents

    Hause, Ben; Rajgarhia, Vineet; Suominen, Pirkko

    2009-05-19

    Recombinant yeast are provided having, in one aspect, multiple exogenous LDH genes integrated into the genome, while leaving native PDC genes intact. In a second aspect, recombinant yeast are provided having an exogenous LDH gene integrated into its genome at the locus of a native PDC gene, with deletion of the native PDC gene. The recombinant yeast are useful in fermentation process for producing lactic acid.

  9. Changes in Lignin and Polysaccharide Components in 13 Cultivars of Rice Straw following Dilute Acid Pretreatment as Studied by Solution-State 2D 1H-13C NMR

    PubMed Central

    Teramura, Hiroshi; Sasaki, Kengo; Oshima, Tomoko; Aikawa, Shimpei; Matsuda, Fumio; Okamoto, Mami; Shirai, Tomokazu; Kawaguchi, Hideo; Ogino, Chiaki; Yamasaki, Masanori; Kikuchi, Jun; Kondo, Akihiko

    2015-01-01

    A renewable raw material, rice straw is pretreated for biorefinery usage. Solution-state two-dimensional (2D) 1H-13 C hetero-nuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) spectroscopy, was used to analyze 13 cultivars of rice straw before and after dilute acid pretreatment, to characterize general changes in the lignin and polysaccharide components. Intensities of most (15 of 16) peaks related to lignin aromatic regions, such as p-coumarate, guaiacyl, syringyl, p-hydroxyphenyl, and cinnamyl alcohol, and methoxyl, increased or remained unchanged after pretreatment. In contrast, intensities of most (11 of 13) peaks related to lignin aliphatic linkages or ferulate decreased. Decreased heterogeneity in the intensities of three peaks related to cellulose components in acid-insoluble residues resulted in similar glucose yield (0.45–0.59 g/g-dry biomass). Starch-derived components showed positive correlations (r = 0.71 to 0.96) with glucose, 5-hydroxymethylfurfural (5-HMF), and formate concentrations in the liquid hydrolysates, and negative correlations (r = –0.95 to –0.97) with xylose concentration and acid-insoluble residue yield. These results showed the fate of lignin and polysaccharide components by pretreatment, suggesting that lignin aromatic regions and cellulose components were retained in the acid insoluble residues and starch-derived components were transformed into glucose, 5-HMF, and formate in the liquid hydrolysate. PMID:26083431

  10. Strong Fluorescent Smart Organogel as a Dual Sensing Material for Volatile Acid and Organic Amine Vapors.

    PubMed

    Xue, Pengchong; Yao, Boqi; Wang, Panpan; Gong, Peng; Zhang, Zhenqi; Lu, Ran

    2015-11-23

    An L-phenylalanine derivative (C12PhBPCP) consisting of a strong emission fluorophore with benzoxazole and cyano groups is designed and synthesized to realize dual responses to volatile acid and organic amine vapors. The photophysical properties and self-assembly of the said derivative in the gel phase are also studied. C12PhBPCP can gelate organic solvents and self-assemble into 1 D nanofibers in the gels. UV/Vis absorption spectral results show H-aggregate formation during gelation, which indicates strong exciton coupling between fluorophores. Both wet gel and xerogel emit strong green fluorescence because the cyano group suppresses fluorescence quenching in the self-assemblies. Moreover, the xerogel film with strong green fluorescence can be used as a dual chemosensor for quantitative detection of volatile acid and organic amine vapors with fast response times and low detection limits owing to its large surface area and amplified fluorescence quenching. The detection limits are 796 ppt and 25 ppb for gaseous aniline and trifluoroacetic acid (TFA), respectively.

  11. Acid rain and weathering damage to carbonate building stone: Results of material loss measurements

    SciTech Connect

    Reddy, M.M.; Youngdahl, C.A.

    1986-11-01

    Marble and limestone specimens were exposed to atmospheric conditions at four eastern US sites. A number of methods were employed for damage assessment; this paper describes the results of chemical and physical measurements of material loss. Good agreement was observed among results obtained with different methods. A rate of surface recession near 15 ..mu..m/y was observed for skyward surfaces of marble tested in North Carolina, and comparable results were obtained at the other test sites. Response of the porous limestone was assessed with greater difficulty; a rate of loss similar to that of marble was inferred. Initial correlations of material loss with environmental factors are briefly discussed.

  12. Acid rain and weathering damage to carbonate building stone: Results of material loss measurements

    SciTech Connect

    Reddy, M.; Youngdahl, C.A.

    1987-01-01

    Marble and limestone specimens were exposed to atmospheric conditions at four eastern U.S. sites. A number of methods were employed for damage assessment; this paper describes the results of chemical and physical measurements of material loss. Good agreement was observed among results obtained with different methods. A rate of surface recession near 15 ..mu..m/y was observed for skyward surfaces of marble tested in North Carolina, and comparable results were obtained at the other test sites. Response of the porous limestone was assessed with greater difficulty; a rate of loss similar to that of marble was inferred. Initial correlations of material loss with environmental factors are briefly discussed.

  13. Composite particles formed by complexation of poly(methacrylic acid) - stabilized magnetic fluid with chitosan: Magnetic material for bioapplications.

    PubMed

    Safarik, Ivo; Stepanek, Miroslav; Uchman, Mariusz; Slouf, Miroslav; Baldikova, Eva; Nydlova, Leona; Pospiskova, Kristyna; Safarikova, Mirka

    2016-10-01

    A simple procedure for the synthesis of magnetic fluid (ferrofluid) stabilized by poly(methacrylic acid) has been developed. This ferrofluid was used to prepare a novel type of magnetically responsive chitosan-based composite material. Both ferrofluid and magnetic chitosan composite were characterized by a combination of microscopy (optical microscopy, TEM, SEM), scattering (static and dynamic light scattering, SANS) and spectroscopy (FTIR) techniques. Magnetic chitosan was found to be a perspective material for various bioapplications, especially as a magnetic carrier for immobilization of enzymes and cells. Lipase from Candida rugosa was covalently attached after cross-linking and activation of chitosan using glutaraldehyde. Baker's yeast cells (Saccharomyces cerevisiae) were incorporated into the chitosan composite during its preparation; both biocatalysts were active after reaction with appropriate substrates.

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

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  15. Development of a research method to measure insoluble and soluble starch in sugarcane factory and refinery products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rapid, quantitative research method using microwave-assisted probe ultrasonication was developed to facilitate the determination of total insoluble, and soluble starch in various sugar factory and refinery products. Several variables that affect starch solubilization were evaluated: 1) conductiv...

  16. Studies of novel hyaluronic acid-collagen sponge materials composed of two different species of type I collagen.

    PubMed

    Lin, Yung-Kai; Liu, Deng-Cheng

    2007-01-01

    The authors have developed novel hyaluronic acid (HA)-collagen sponge materials (HACSMs) composed of various ratios of bird feet (BF) and pig skin (PS) collagen that are fabricated employing a combination of freezing, lyophilizing, and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) crosslinking methods. Morphology, swelling ratio, resistance to collagenase, thermal stability, tensile strength, and free amine index are determined to evaluate the physical-chemical properties of various HACSMs. Different BF: PS ratios directly vary with the physical-chemical properties of HACSMs and control their biodegradability for multiple uses. Resistance to collagenase, thermal stability, and tensile strength of HACSMs increases as the ratio of BF collagen increases. On the contrary, the higher swelling ratio, free amine index, and pore size occur in materials composed of higher ratios of PS collagen. A linear relationship between the decreased ratio of PS collagen and the increase in tensile strength and biostability are observed. The materials of B4P1HA (BF: PS: HA=4: 1: 0.2) exhibit the highest value of tensile strength, but no significant difference exists between B4P1HA and B5P0HA (BF: PS: HA=5: 0: 0.2). These phenomena should be closely related to the BF collagen which contains a higher amount of carboxyl groups of glutamic or aspartic acid residues and forms more amine bonds under EDC cross-linking when compared to PS collagen. However, these results suggest that the B4P1HA and B5P0HA materials should be produced according to highest bio-stability and mechanical strength and, furthermore they may be suitable for artificial skin or drug delivery applications.

  17. Porous carbon material containing CaO for acidic gas capture: preparation and properties.

    PubMed

    Przepiórski, Jacek; Czyżewski, Adam; Pietrzak, Robert; Toyoda, Masahiro; Morawski, Antoni W

    2013-12-15

    A one-step process for the preparation of CaO-containing porous carbons is described. Mixtures of poly(ethylene terephthalate) with natural limestone were pyrolyzed and thus hybrid sorbents could be easily obtained. The polymeric material and the mineral served as a carbon precursor and CaO delivering agent, respectively. We discuss effects of the preparation conditions and the relative amounts of the raw materials used for the preparations on the porosity of the hybrid products. The micropore areas and volumes of the obtained products tended to decrease with increasing CaO contents. Increase in the preparation temperature entailed a decrease in the micropore volume, whereas the mesopore volume increased. The pore creation mechanism is proposed on the basis of thermogravimetric and temperature-programmed desorption measurements. The prepared CaO-containing porous carbons efficiently captured SO2 and CO2 from air. Washing out of CaO from the hybrid materials was confirmed as a suitable method to obtain highly porous carbon materials.

  18. Comparative study on functionalized SBA-15 and SBA-16 nanostructured materials used for immobilization of D-amino acid oxidase

    NASA Astrophysics Data System (ADS)

    Hy, Le Gia; Phuong, Dang Tuyet; Yen, Hoang; Hoan, Nguyen Thi Vuong; Linh, Bui Thi Hai; Thang, Hoang vinh; Hoa, Tran Thi Kim; Thang, Dinh Cao; Nguyen, Vu Thi Hanh; Thao, Phan Thi Hong; Giap, Chu Van; Tuan, Vu Anh

    2008-12-01

    SBA-15 and SBA-16 nanostucrured materials were synthesized via hydrothermal treatment and were functionalized with 3-aminopropyltriethoxysilane (APTES), and vinyltriethoxysilane (VTES). The obtained samples were characterized by different techniques such as XRD, BET, IR and TEM. After functionalization, it showed that these nanostrucrured materials were still maintained the hexagonal pore structure of the parent SBA-15 and cubic cage structure of the parent SBA-16. The non-functionalized pure silica SBA-15 and SBA-16 as well as functionalized SBA-15 and SBA-16 materials were used to immobilize DAAO, which is industrially important enzyme for the production of glutaryl 7-amino cephalosporanic acid (GL-7-ACA) from cephalosporin C (CPC). The obtained results revealed that functionalized SBA- 15 and SBA-16 materials exhibited higher enzymatic activity and stability than those of non-functionalized ones. This might be due to the enhancing of surface hydrophobicity upon functionalization. The surface functionalization of the nanostructured silicas with organic groups can enhance the interaction between enzyme and the supports and consequently increasing the operational stability of the immobilized enzyme. The loading of enzyme on SBA-15 materials was higher than that on SBA-16 samples (both functionalized and non-functionalized types). This might be explained by the difference in pore size and type (cylindrical for SBA-15 and bottle-neck for SBA-16) as well as structure shape (hexagonal for SBA-15 and cubic cage for SBA-16) of both mesoporous materials. Additionally, nature of functionalized groups significantly affected the enzymatic activity. Effects on surface binding force, nature of functional groups, pore size of supports were investigated and discussed.

  19. The Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface: Micro-Gravity Experiments and Theoretical Developments

    NASA Technical Reports Server (NTRS)

    Catalina, Adrian V.; Ssen, Subhayu; Stefanescu, Doru M.

    2003-01-01

    The interaction of an insoluble particle with an advancing solid/liquid interface (SLI) has been a subject of investigation for the past four decades. While the original interest stemmed from geology applications (e.g., frost heaving in soil), researchers soon realized that the complex science associated with such an interaction is relevant to many other scientific fields encompassing metal matrix composites (MMCs), high temperature superconductors, inclusion management in steel, growth of monotectics, and preservation of biological cells. During solidification of a liquid containing an insoluble particle, three distinct interaction phenomena have been experimentally observed: instantaneous engulfment of the particle, continuous pushing, and particle pushing followed by engulfment. It was also observed that for given experimental conditions and particle size there is a critical solidification velocity, V(sub cr), above which a particle is engulfed. During solidification of MMCs pushing leads to particle agglomeration at the grain boundaries and this has detrimental effects on mechanical properties of the casting. Consequently, the process must be designed for instantaneous engulfment to occur. This implies the development of accurate theoretical models to predict V(sub cr), and perform benchmark experiments to test the validity of such models. Although considerable progress has been made in understanding the pushing/engulfment phenomenon (PEP), its quantification in terms of the material and processing parameters remains a focus of research. Since natural convection currents occurring during terrestrial solidification experiments complicate the study of PEP, execution of experiments on the International Space Station (ISS) has been approved and funded by NASA. Extensive terrestrial (1g) experiments and preliminary micro-gravity (mu g) experiments on two space shuttle missions have been conducted in preparation for future experiments on the ISS. The investigated

  20. Strength determination of periodontal splints fabricated from acid-etched retained materials.

    PubMed

    Compton, F H; Beagrie, G S; Chernecky, R

    1977-07-01

    Six systems (one polycarboxylate, one polymethyl methacrylate, one unfilled BIS-GMA resin, two combinations of methyl cyanoacrylate and polymethyl methacrylate, and one combination of unfilled BIS-GMA and filled composite resin) were evaluated for in vitro retention to acid-etched human enamel. Also tested were one unfilled-filled resin combination backed by perforated orthodontic band metal and another unfilled resin backed by stainless steel wire mesh. Significant differences in retention were found. Results show that retention depends pril surface and to resist subsequent chemical degradation.

  1. SORPTION BEHAVIOR OF MONOSODIUM TITANATE AND AMORPHOUS PEROXOTITANATE MATERIALS UNDER WEAKLY ACIDIC CONDITIONS

    SciTech Connect

    Hobbs, D.; Elvington, M.; Click, D.

    2009-11-11

    Inorganic, titanate-based sorbents are tested with respect to adsorption of a variety of sorbates under weakly acidic conditions (pH 3). Specifically, monosodium titanate (MST) and amorphous peroxotitanate (APT) sorption characteristics are initially probed through a screening process consisting of a pair of mixed metal solutions containing a total of 29 sorbates including alkali metals, alkaline earth metals, transition metals, metalloids and nonmetals. MST and APT sorption characteristics are further analyzed individually with chromium(III) and cadmium(II) using a batch method at ambient laboratory temperature, varying concentrations of the sorbents and sorbates and contact times. Maximum sorbate loadings are obtained from the respective adsorption isotherms.

  2. Using a Simulated Industrial Setting for the Development of an Improved Solvent System for the Recrystallization of Benzoic Acid: A Student-Centered Project

    ERIC Educational Resources Information Center

    Hightower, Timothy R.; Heeren, Jay D.

    2006-01-01

    Recrystallization of benzoic acid is an excellent way to remove insoluble impurities. In a traditional organic laboratory experiment, insoluble impurities are removed through the recrystallization of benzoic acid utilizing water as the recrystallization solvent. It was our goal to develop a peer-led, problem-solving organic laboratory exercise…

  3. Studies on the oxidation of hexamethylbenzene 2: Preparation of dimethylpyromellitic acid

    NASA Technical Reports Server (NTRS)

    Chiba, K.; Tomura, S.

    1986-01-01

    Hexamethylbenzene (HMB) was difficult to be oxidized with an alkaline potassium permanganate solution, since HMB was insoluble in an aqueous alkaline solution. But, when HMB was warmed with 50% nitric acid for a short time, and then treated with aqueous potassium permanganate, the reaction occurred readily and dimethylpyromellitic acid was obtained. When HMB was warmed with 50% nitric acid for 1 to 2 minutes, a yellow material was produced, which was soluble in hot aqueous potassium hydroxide, though free from carboxylic acids. It contained a little amount of bis-(nitromethyl)prehnitene and several unknown compounds. Further, the heat stability of polyimide prepared by the reaction of tetramethyldimethylpyromellitate with 4,4 prime-diaminodiphenylmethane turned out to be nearly equal to that of polyimide prepared from tetramethylpyromellitate.

  4. Alveolar retention and clearance of insoluble particles in rats simulated by a new physiology-oriented compartmental kinetics model

    SciTech Connect

    Stoeber, W.M.; Morrow, P.E.; Morawietz, G. )

    1990-08-01

    A physiology-oriented compartmental kinetics model of alveolar retention of inhaled insoluble particulate matter in rat lungs was proposed in a recent paper, and the retention patterns obtained with the model for a hypothetical set of input data appeared to simulate phenomena which were observed in inhalation studies with Fischer 344 rats. The present paper represents the results of applying the new model for simulations of the actual experimental retention data of five different inhalation studies with Fischer 344 rats exposed to three different materials. The experimental data showed that model adjustments had to be made in order to account for clearance effects that appeared to be influenced by the age of the animals. After these adjustments were made and an appropriate set of values for the model parameters describing the respective exposure conditions was used, the model was constrained to represent the empirical data of all of the studies by one unique set of parameter values. Changes in particular values of this set were considered to be acceptable only if they reflected changes of relevant properties of the inhaled particulate matter. The final simulations did not completely comply with this self-imposed criterion. However, the degree of compliance and the simulation quality achieved with a minimum of parameter variations seem to be unprecedented in retention modeling. The results of the study encourage attempts for further refining the present model.

  5. Ligand-induced association of surface immunoglobulin with the detergent insoluble cytoskeleton may involve an 89K protein

    SciTech Connect

    Gupta, S.K.; Woda, B.

    1986-03-01

    Membrane immunoglobulin of B-lymphocytes is thought to play an important role in antigen recognition and cellular activation. Binding of cross-linking ligands to surface immunoglobulin (SIg) on intact cells converts it to a detergent insoluble state, and this conversion is associated with the transmission of a mitogenic signal. Insolubilized membrane proteins may be solubilized by incubating the detergent insoluble cytoskeletons in buffers which convert F-actin to G-actin ((Buffer 1), 0.34M sucrose, 0.5mM ATP, 0.5mM Dithiothrietol and lmM EDTA). Immunoprecipitation of SIg from the detergent soluble fraction of /sup 35/S-methionine labeled non ligand treated rat B-cells results in the co-isolation of an 89K protein and a 44K protein, presumably actin. The 89K protein is not associated with the fraction of endogenous detergent insoluble SIg. On treatment of rat B cells with cross-linking ligand (anti-Ig) the 89K protein becomes detergent insoluble along with most of the SIg and co-isolates with SIg on immunoprecipitation of the detergent insoluble, buffer l solubilized fraction. The migration of the SIg-associated 89K protein from the detergent soluble fraction to the detergent insoluble fraction after ligand treatment, suggests that this protein might be involved in linking SIg to the underlying cytoskeleton and could be involved in the transmission of a mitogenic signal.

  6. Synthesis and characterization of new composite materials based on poly(methacrylic acid) and hydroxyapatite with applications in dentistry.

    PubMed

    Cucuruz, Andrei Tiberiu; Andronescu, Ecaterina; Ficai, Anton; Ilie, Andreia; Iordache, Florin

    2016-08-30

    The use of methacrylic acid (MAA) in medicine was poorly investigated in the past but can be of great importance because the incorporation of hydroxyapatite (HA) can lead to new composite materials with good properties due to the strong electrostatic interactions between carboxylate groups of polymer and Ca(2+) ions from HA. The scope of this study was to determine the potential of using composite materials based on poly(methacrylic acid) (PMAA) and hydroxyapatite in dentistry. Two routes of synthesis were taken into account: i) HA was synthesised in situ and ii) commercial HA was used. Fourier transform infrared spectroscopy and X-ray diffraction were used for compositional assessments. Scanning electron microscopy was performed to determine the morphology and differential thermal analysis (DTA) coupled with thermogravimetric analysis (TG) was used to study the thermal behaviour and to observe quantitative changes. In-vitro tests were also performed in order to evaluate the biocompatibility of both PMAA/HA composites by monitoring the development potential of human endothelial cells using MTT assay and fluorescent microscopy.

  7. Preparation of a multifunctional material with superhydrophobicity, superparamagnetism, mechanical stability and acids-bases resistance by electrospinning

    NASA Astrophysics Data System (ADS)

    Wang, Shuai; Liu, Qingwen; Zhang, Yang; Wang, Shaodan; Li, Yaoxian; Yang, Qingbiao; Song, Yan

    2013-08-01

    A multifunctional material with superhydrophobicity, superparamagnetism, mechanical stability and acids-bases resistance was developed from the bead-on-string PVDF and Fe3O4@SiO2@POTS nanoparticles by electrospinning in this work. The Fe3O4@SiO2@POTS nanoparticles which have excellent superparamagnetism were successfully prepared and subsequently introduced into PVDF precursor solution. Through electrospinning, Fe3O4@SiO2@POTS nanoparticles irregularly distributed in the membrane to not only make a dual-scale roughness which is beneficial to obtain a superhydrophobic surface but also stimulate the material turns to superparamagnetic for wider use in different fields. More importantly, the film shows stable superhydrophobicity even for many corrosive solutions, such as acidic or basic solutions over a wide pH range and remarkable mechanical stability. The composition and surface structure of the film are the two critical factors that induce such unusual properties. The weight ratio of Fe3O4@SiO2@POTS/PVDF can strongly influence the superhydrophobicity and mechanical properties of the composite films.

  8. Evaluation of gallic acid loaded zein sub-micron electrospun fibre mats as novel active packaging materials.

    PubMed

    Neo, Yun Ping; Swift, Simon; Ray, Sudip; Gizdavic-Nikolaidis, Marija; Jin, Jianyong; Perera, Conrad O

    2013-12-01

    The applicability of gallic acid loaded zein (Ze-GA) electrospun fibre mats towards potential active food packaging material was evaluated. The surface chemistry of the electrospun fibre mats was determined using X-ray photon spectroscopy (XPS). The electrospun fibre mats showed low water activity and whitish colour. Thermogravimetric analysis (TGA) and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy revealed the stability of the fibre mats over time. The Ze-GA fibre mats displayed similar rapid release profiles, with Ze-GA 20% exhibiting the fastest release rate in water as compared to the others. Gallic acid diffuses from the electrospun fibres in a Fickian diffusion manner and the data obtained exhibited a better fit to Higuchi model. L929 fibroblast cells were cultured on the electrospun fibres to demonstrate the absence of cytotoxicity. Overall, the Ze-GA fibre mats demonstrated antibacterial activity and properties consistent with those considered desirable for active packaging material in the food industry.

  9. Morphological study of Insoluble Organic Matter from carbonaceous chondrites: Correlation with petrologic grade

    NASA Astrophysics Data System (ADS)

    Changela, Hitesh G.

    2015-06-01

    The major form of organic material delivered to Earth from an extraterrestrial origin is Insoluble Organic Matter (IOM). A morphological study of IOM in the CR (Renazzo-type) and CM (Mighei-type) carbonaceous chondrites was performed in order to constrain its origins and processing history. IOM residues from the following CR chondrites: GRO 95577 (CR1), Al Rais (CR1/2), EET 92042 (CR2), QUE 99177 (CR3) and the CM chondrites: MET 01070 (CM2.2), Cold Bokkeveld (CM2.3), Murchison (CM2.4) and QUE 97990 (CM2.5) were studied using Annular Dark Field STEM imaging. Characteristic features of the IOM, organic nanoglobules, were manually identified and measured for their abundances and size distributions. The IOM residues were also compared holistically for their degree of average 'roughness' or 'coarsening' using fractal image analysis. Manually identified nanoglobules have abundances making up less than 10% of the total IOM, which is consistent with previous studies. Their measured abundances do not correlate with petrologic grade. Thus parent body processing did not systematically deplete their abundances. The IOM is however on average 'smoother' or 'coarser' in the more altered chondrites, demonstrated by a lower fractal dimension using fractal box counting (DB). The DB values for the IOM in the CR chondrites are distinctive: QUE 99177 has the largest DB value (average = 1.54 ± 0.004) and GRO 99577 has the lowest (average = 1.45 ± 0.011). Al Rais and EET 92042 have IOM with average DB values within this range (average, 1.46 ± 0.009 and 1.50 ± 0.006). The CMs record a similar but less distinctive trend in DB, with QUE 97990 having the largest value (1.52 ± 0.004), MET 01070 the lowest (1.45 ± 0.019), and Cold Bokkeveld (1.50 ± 0.011) and Murchison (1.49 ± 0.017) equivalent to one another within error. The identified nanoglobules in the IOM of the CM chondrites are on average larger than those in the CR chondrites. The 'coarsening' or 'smoother' texture of the IOM

  10. Time Dependence of Material Properties of Polyethylene Glycol Hydrogels Chain Extended with Short Hydroxy Acid Segments

    PubMed Central

    Barati, Danial; Moeinzadeh, Seyedsina; Karaman, Ozan; Jabbari, Esmaiel

    2014-01-01

    The objective of this work was to investigate the effect of chemical composition and segment number (n) on gelation, stiffness, and degradation of hydroxy acid-chain-extended star polyethylene glycol acrylate (SPEXA) gels. The hydroxy acids included glycolide (G,), L-lactide (L), p-dioxanone (D) and -caprolactone (C). Chain-extension generated water soluble macromers with faster gelation rates, lower sol fractions, higher compressive moduli, and a wide-ranging degradation times when crosslinked into a hydrogel. SPEGA gels with the highest fraction of inter-molecular crosslinks had the most increase in compressive modulus with n whereas SPELA and SPECA had the lowest increase in modulus. SPEXA gels exhibited a wide range of degradation times from a few days for SPEGA to a few weeks for SPELA, a few months for SPEDA, and many months for SPECA. Marrow stromal cells and endothelial progenitor cells had the highest expression of vasculogenic markers when co-encapsulated in the faster degrading SPELA gel. PMID:25267858

  11. A comparison of water solubility enhancements of organic solutes by aquatic humic materials and commercial humic acids

    USGS Publications Warehouse

    Chlou, C.T.; Kile, D.E.; Brinton, T.I.; Malcolm, R.L.; Leenheer, J.A.; MacCarthy, P.

    1987-01-01

    Water solubility enhancements of 1,1-bis(p-chloro-phenyl)-2,2,2-trichloroethane (p,p???-DDT), 2,4,5,2???,5???-pentachlorobiphenyl (2,4,5,2???,5???-PCB), and 2,4,4???-tri-chlorobiphenyl (2,4,4???-PCB) by dissolved organic matter have been studied with the following samples: (1) acidic water samples from the Suwannee River, Georgia, and the Sopchoppy River, Florida; (2) a humic extract of a nearly neutral pH water from the Calcasieu River, Louisiana; (3) commercial humic acids from the Aldrich Chemical Co. and Fluka-Tridom Chemical Corp. The calculated partition coefficients on a dissolved organic carbon basis (Kdoc) for organic solutes with water samples and aquatic humic extracts from this and earlier studies indicate that the enhancement effect varies with the molecular composition of the aquatic humic materials. The Kdoc values with water and aquatic humic samples are, however, far less than the observed Kdoc values obtained with the two commercial samples, by factors of about 4-20. In view of this finding, one should be cautious in interpreting the effects of the dissolved organic matter on solubility enhancement of organic solutes on the basis of the use of commercial humic acids.

  12. Self-assembly of nucleic acids, silk and hybrid materials thereof.

    PubMed

    Humenik, Martin; Scheibel, Thomas

    2014-12-17

    Top-down approaches based on etching techniques have almost reached their limits in terms of dimension. Therefore, novel assembly strategies and types of nanomaterials are required to allow technological advances. Self-assembly processes independent of external energy sources and unlimited in dimensional scaling have become a very promising approach. Here,we highlight recent developments in self-assembled DNA-polymer, silk-polymer and silk-DNA hybrids as promising materials with biotic and abiotic moieties for constructing complex hierarchical materials in ‘bottom-up’ approaches. DNA block copolymers assemble into nanostructures typically exposing a DNA corona which allows functionalization, labeling and higher levels of organization due to its specific addressable recognition properties. In contrast, self-assembly of natural silk proteins as well as their recombinant variants yields mechanically stable β-sheet rich nanostructures. The combination of silk with abiotic polymers gains hybrid materials with new functionalities. Together, the precision of DNA hybridization and robustness of silk fibrillar structures combine in novel conjugates enable processing of higher-order structures with nanoscale architecture and programmable functions.

  13. Self-assembly of nucleic acids, silk and hybrid materials thereof

    NASA Astrophysics Data System (ADS)

    Humenik, Martin; Scheibel, Thomas

    2014-12-01

    Top-down approaches based on etching techniques have almost reached their limits in terms of dimension. Therefore, novel assembly strategies and types of nanomaterials are required to allow technological advances. Self-assembly processes independent of external energy sources and unlimited in dimensional scaling have become a very promising approach. Here, we highlight recent developments in self-assembled DNA-polymer, silk-polymer and silk-DNA hybrids as promising materials with biotic and abiotic moieties for constructing complex hierarchical materials in ‘bottom-up’ approaches. DNA block copolymers assemble into nanostructures typically exposing a DNA corona which allows functionalization, labeling and higher levels of organization due to its specific addressable recognition properties. In contrast, self-assembly of natural silk proteins as well as their recombinant variants yields mechanically stable β-sheet rich nanostructures. The combination of silk with abiotic polymers gains hybrid materials with new functionalities. Together, the precision of DNA hybridization and robustness of silk fibrillar structures combine in novel conjugates enable processing of higher-order structures with nanoscale architecture and programmable functions.

  14. Hollow mesoporous silica as a high drug loading carrier for regulation insoluble drug release.

    PubMed

    Geng, Hongjian; Zhao, Yating; Liu, Jia; Cui, Yu; Wang, Ying; Zhao, Qinfu; Wang, Siling

    2016-08-20

    The purpose of this study was to develop a high drug loading hollow mesoporous silica nanoparticles (HMS) and apply for regulation insoluble drug release. HMS was synthesized using hard template phenolic resin nanoparticles with the aid of cetyltrimethyl ammonium bromide (CTAB), which was simple and inexpensive. To compare the difference between normal mesoporous silica (NMS) and hollow mesoporous silica in drug loading efficiency, drug release behavior and solid state, NMS was also prepared by soft template method. Transmission electron microscopy (TEM), specific surface area analysis, FT-IR and zeta potential were employed to characterize the morphology structure and physicochemical property of these carriers. The insoluble drugs, carvedilol and fenofibrate(Car and Fen), were chosen as the model drug to be loaded into HMS and NMS. We also chose methylene blue (MB) as a basic dye to estimate the adsorption ability of these carriers from macroscopic and microscopic view, and the drug-loaded carriers were systematically studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and UV-vis spectrophotometry. What' more, the in vivo process of HMS was also study by confocal microscopy and in vivo fluorescence imaging. In order to confirm the gastrointestinal safety of HMS, the pathological examination of stomach and intestine also be evaluated. HMS allowed a higher drug loading than NMS and exhibited a relative sustained release curve, while NMS was immediate-release. And the effect of preventing drugs crystallization was weaker than NMS. As for in vivo process, HMS was cleared relatively rapidly from the mouse gastrointestinal and barely uptake by intestinal epithelial cell in this study due to its large particle size. And the damage of HMS to gastrointestinal could be ignored. This study provided a simple method to obtain high drug loading and regulation insoluble drug release, expanded the application of inorganic carriers in drug delivery system

  15. Environmental monitoring study of linear alkylbenzene sulfonates and insoluble soap in Spanish sewage sludge samples.

    PubMed

    Cantarero, Samuel; Zafra-Gómez, Alberto; Ballesteros, Oscar; Navalón, Alberto; Reis, Marco S; Saraiva, Pedro M; Vílchez, José L

    2011-01-01

    In this work we present a monitoring study of linear alkylbenzene sulfonates (LAS) and insoluble soap performed on Spanish sewage sludge samples. This work focuses on finding statistical relations between LAS concentrations and insoluble soap in sewage sludge samples and variables related to wastewater treatment plants such as water hardness, population and treatment type. It is worth to mention that 38 samples, collected from different Spanish regions, were studied. The statistical tool we used was Principal Component Analysis (PC), in order to reduce the number of response variables. The analysis of variance (ANOVA) test and a non-parametric test such as the Kruskal-Wallis test were also studied through the estimation of the p-value (probability of obtaining a test statistic at least as extreme as the one that was actually observed, assuming that the null hypothesis is true) in order to study possible relations between the concentration of both analytes and the rest of variables. We also compared LAS and insoluble soap behaviors. In addition, the results obtained for LAS (mean value) were compared with the limit value proposed by the future Directive entitled "Working Document on Sludge". According to the results, the mean obtained for soap and LAS was 26.49 g kg(-1) and 6.15 g kg(-1) respectively. It is worth noting that LAS mean was significantly higher than the limit value (2.6 g kg(-1)). In addition, LAS and soap concentrations depend largely on water hardness. However, only LAS concentration depends on treatment type.

  16. Dietary total and insoluble fiber intakes are inversely associated with prostate cancer risk.

    PubMed

    Deschasaux, Mélanie; Pouchieu, Camille; His, Mathilde; Hercberg, Serge; Latino-Martel, Paule; Touvier, Mathilde

    2014-04-01

    Although experimental data suggest a potentially protective involvement of dietary fiber in prostate carcinogenesis, very few prospective studies have investigated the relation between dietary fiber intake and prostate cancer risk, and those have had inconsistent results. Our objective was to study the association between dietary fiber intake (overall, insoluble, soluble, and from different sources, such as cereals, vegetables, fruits, and legumes) and prostate cancer risk. Stratifications by excess weight status, insulin-like growth factors, and amount of alcohol intake were also considered. This prospective analysis included 3313 men from the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) cohort who completed at least 3 24-h dietary records. One hundred thirty-nine incident prostate cancers were diagnosed between 1994 and 2007 (median follow-up of 12.6 y). Associations between quartiles of energy-adjusted dietary fiber intake and prostate cancer risk were characterized by multivariate Cox proportional hazards models. Prostate cancer risk was inversely associated with total dietary fiber intake (HR of quartile 4 vs. quartile 1 = 0.47; 95% CI: 0.27, 0.81; P = 0.001), insoluble (HR = 0.46; 95% CI: 0.27, 0.78; P = 0.001), and legume (HR = 0.55; 95% CI: 0.32, 0.95; P = 0.04) fiber intakes. In contrast, we found no association between prostate cancer risk and soluble (P = 0.1), cereal (P = 0.7), vegetable (P = 0.9), and fruit (P = 0.4) fiber intakes. In conclusion, dietary fiber intake (total, insoluble, and from legumes but not soluble or from cereals, vegetables, and fruits) was inversely associated with prostate cancer risk, consistent with mechanistic data.

  17. Anti-tau antibody reduces insoluble tau and decreases brain atrophy

    PubMed Central

    Yanamandra, Kiran; Jiang, Hong; Mahan, Thomas E; Maloney, Susan E; Wozniak, David F; Diamond, Marc I; Holtzman, David M

    2015-01-01

    Objective We previously found a strong reduction in tau pathology and insoluble tau in P301S tau transgenic mice following intracerebroventricular infusion of the anti-tau antibody HJ8.5. We sought to determine the effects of HJ8.5 in the same model following peripheral administration. Methods The primary objective was to determine if HJ8.5 administered at a dose of 50 mg kg−1 week−1 by intraperitoneal (IP) injection to 6-month-old P301S mice for 3 months would influence phospho-tau (p-tau) accumulation, tau insolubility, and neurodegeneration. Results Treatment with HJ8.5 at 50 mg/kg showed a very strong decrease in detergent-insoluble tau. Importantly, HJ8.5 significantly reduced the loss of cortical and hippocampal tissue volumes compared to control treated mice. HJ8.5 treatment reduced hippocampal CA1 cellular layer staining with the p-tau antibody AT8 and thio-S-positive tau aggregates in piriform cortex and amygdala. Moreover, mice treated with HJ8.5 at 50 mg/kg showed a decrease in motor/sensorimotor deficits compared to vehicle-treated mice. Some effects of HJ8.5, including reduction in brain atrophy, and p-tau immunostaining were also seen with a dose of 10 mg kg−1 week−1. In BV2-microglial cells, we observed significantly higher uptake of P301S tau aggregates in the presence of HJ8.5. HJ8.5 treatment also resulted in a large dose-dependent increase of tau in the plasma. Interpretation Our results indicate that systemically administered anti-tau antibody HJ8.5 significantly decreases insoluble tau, decreases brain atrophy, and improves motor/sensorimotor function in a mouse model of tauopathy. These data further support the idea that anti-tau antibodies should be further assessed as a potential treatment for tauopathies. PMID:25815354

  18. Immunization in vitro and production of monoclonal antibodies specific to insoluble and weakly immunogenic proteins.

    PubMed Central

    Van Ness, J; Laemmli, U K; Pettijohn, D E

    1984-01-01

    A procedure is described for immunizing in vitro and stimulating proliferation of specific B-cell lymphocytes. The method is applicable to production of monoclonal antibodies against proteins that are soluble only in denaturing solvents. An induction period is described in which antigen is presented to the B-cell population in the absence of serum. Also, antigen is coupled to mitogenic silica, which allows the effective presentation of both soluble and insoluble antigens. The results indicate hybridomas can be obtained that secrete IgMs directed against highly conserved or weakly immunogenic antigens. Images PMID:6083563

  19. Corrosion-resistant iridium-platinum anode material for high polarization application in corrosive acids

    SciTech Connect

    Farmer, J.; Summers, L.; Lewis, P.

    1993-09-08

    The present invention relates to highly corrosion resistant components for use in an electrochemical cell. Specifically, these components are resistant to corrosion under very extreme conditions such as exposure to aqua regia in the presence of a constant current density of 100mA/m{sup 2}. The components are comprised of an iridium-platinum alloy that comprises less than 30% iridium. In a preferred embodiment of the present invention, the iridium-platinum alloy comprises 15-20% iridium. In another preferred embodiment of the present invention, the iridium-platinum alloy is deposited on the surface of an electrochemical cell component by magnetron sputtering. The present invention also relates to a method for conducting an electrochemical reaction in the presence of highly corrosive acids under a high degree of polarization wherein the electrochemical cell comprises a component, preferably the anode, containing an iridium-platinum alloy that comprises less than 30% iridium.

  20. Unusual effects of monocarboxylic acids on the structure and on the transport and mechanical properties of chitosan films.

    PubMed

    Chen, Fei; Gällstedt, Mikael; Olsson, Richard T; Gedde, Ulf W; Hedenqvist, Mikael S

    2015-11-05

    The purpose of this study was to study the transport of monocarboxylic acids in chitosan films, since this is important for understanding and predicting the drying kinetics of chitosan from aqueous solutions. Despite the wealth of data on chitosan films prepared from aqueous monocarboxylic acid solutions, this transport has not been reported. Chitosan films were exposed to formic, acetic, propionic and butyric acid vapours, it was found that the rate of uptake decreased with increasing molecular size. The equilibration time was unexpectedly long, especially for propionic and butyric acid, nine months. A clear two-stage uptake curve was observed for propionic acid. Evidently, the rate of uptake was determined by acid-induced changes in the material. X-ray diffraction and infrared spectroscopy indicated that the structure of the chitosan acetate and buffered chitosan films changed during exposure to acid and during the subsequent drying. The dried films previously exposed to the acid showed less crystalline features than the original material and a novel repeating structure possibly involving acid molecules. The molar mass of the chitosan decreased on exposure to acid but tensile tests revealed that the films were always ductile. The films exposed to acid vapour (propionic and butyric acid) for the longest period of time were insoluble in the size-exclusion chromatography eluent, and they were also the most ductile/extensible of all samples studied.

  1. Materials

    NASA Technical Reports Server (NTRS)

    Glaessgen, Edward H.; Schoeppner, Gregory A.

    2006-01-01

    NASA Langley Research Center has successfully developed an electron beam freeform fabrication (EBF3) process, a rapid metal deposition process that works efficiently with a variety of weldable alloys. The EBF3 process can be used to build a complex, unitized part in a layer-additive fashion, although the more immediate payoff is for use as a manufacturing process for adding details to components fabricated from simplified castings and forgings or plate products. The EBF3 process produces structural metallic parts with strengths comparable to that of wrought product forms and has been demonstrated on aluminum, titanium, and nickel-based alloys to date. The EBF3 process introduces metal wire feedstock into a molten pool that is created and sustained using a focused electron beam in a vacuum environment. Operation in a vacuum ensures a clean process environment and eliminates the need for a consumable shield gas. Advanced metal manufacturing methods such as EBF3 are being explored for fabrication and repair of aerospace structures, offering potential for improvements in cost, weight, and performance to enhance mission success for aircraft, launch vehicles, and spacecraft. Near-term applications of the EBF3 process are most likely to be implemented for cost reduction and lead time reduction through addition of details onto simplified preforms (casting or forging). This is particularly attractive for components with protruding details that would require a significantly large volume of material to be machined away from an oversized forging, offering significant reductions to the buy-to-fly ratio. Future far-term applications promise improved structural efficiency through reduced weight and improved performance by exploiting the layer-additive nature of the EBF3 process to fabricate tailored unitized structures with functionally graded microstructures and compositions.

  2. Amino acid derivative-mediated detoxification and functionalization of dual cure dental restorative material for dental pulp cell mineralization.

    PubMed

    Minamikawa, Hajime; Yamada, Masahiro; Iwasa, Fuminori; Ueno, Takeshi; Deyama, Yoshiaki; Suzuki, Kuniaki; Yawaka, Yasutaka; Ogawa, Takahiro

    2010-10-01

    Current dental restorative materials are only used to fill the defect of hard tissues, such as dentin and enamel, because of their cytotoxicity. Therefore, exposed dental pulp tissues in deep cavities must be first covered by a pulp capping material like calcium hydroxide to form a layer of mineralized tissue. However, this tissue mineralization is based on pathological reaction and triggers long-lasting inflammation, often causing clinical problems. This study tested the ability of N-acetyl cysteine (NAC), amino acid derivative, to reduce cytotoxicity and induce mineralized tissue conductivity in resin-modified glass ionomer (RMGI), a widely used dental restorative material having dual cure mechanism. Rat dental pulp cells were cultured on untreated or NAC-supplemented RMGI. NAC supplementation substantially increased the percentage of viable cells from 46.7 to 73.3% after 24-h incubation. Cell attachment, spreading, proliferative activity, and odontoblast-related gene and protein expressions increased significantly on NAC-supplemented RMGI. The mineralization capability of cells, which was nearly suppressed on untreated RMGI, was induced on NAC-supplemented RMGI. These improved behaviors and functions of dental pulp cells on NAC-supplemented RMGI were associated with a considerable reduction in the production of intracellular reactive oxygen species and with the increased level of intracellular glutathione reserves. These results demonstrated that NAC could detoxify and functionalize RMGIs via two different mechanisms involving in situ material detoxification and antioxidant cell protection. We believe that this study provides a new approach for developing dental restorative materials that enables mineralized tissue regeneration.

  3. Solar driven nitrous acid formation on building material surfaces containing titanium dioxide: A concern for air quality in urban areas?

    NASA Astrophysics Data System (ADS)

    Langridge, Justin M.; Gustafsson, R. Joel; Griffiths, Paul T.; Cox, R. Anthony; Lambert, Richard M.; Jones, Roderic L.

    The photoenhanced uptake of nitrogen dioxide (NO 2) to the surface of commercially available self-cleaning window glass has been studied under controlled laboratory conditions. This material is one of an array of modern building products which incorporate titanium dioxide (TiO 2) nanoparticles and are finding increasing use in populated urban areas. Amongst the principal drivers for the use of these materials is that they are thought to facilitate the irreversible removal of pollutants such as NO 2 and organic molecules from the atmosphere and thus act to remediate air quality. While it appears that TiO 2 materials do indeed remove organic molecules from built environments, in this study we show that the photoenhanced uptake of NO 2 to one example material, self-cleaning window glass, is in fact accompanied by the substantial formation (50-70%) of gaseous nitrous acid (HONO). This finding has direct and serious implications for the use of these materials in urban areas. Not only is HONO a harmful respiratory irritant, it is also readily photolysed by solar radiation leading to the formation of hydroxyl radicals (OH) together with the re-release of NO x as NO. The net effect of subsequent OH initiated chemistry can then be the further degradation of air quality through the formation of secondary pollutants such as ozone and VOC oxidation products. In summary, we suggest that a scientifically conceived technical strategy for air quality remediation based on this technology, while widely perceived as universally beneficial, could in fact have effects precisely opposite to those intended.

  4. [Bound amino acids in local strains of Trichomonas vaginalis].

    PubMed

    Tsvetkova, A; Osinovski, E; Vasilevska, M

    1990-01-01

    Amino acid composition of water-soluble and water-insoluble proteins of 8 strains of Tr. vaginalis is studied. 17 amino acids are found in both protein hydrolyzates. Despite the complete coincidence of their qualitative compositions there are reliable differences in the quantitative contents of some amino acids. Differences in the contents of main amino acids of water-soluble proteins of different strains reflect the belonging of the latter to different sero-groups. No reliable differences in the quantitative contents of amino acids of both water-soluble and water-insoluble proteins in strains belonging to one sero-group are recognised.

  5. Copper release from dental prosthetic crowns, dental materials, and human teeth into acetic acid.

    PubMed

    Kalicanin, Biljana M; Nikolić, Ruzica S

    2010-01-01

    This article examines the dilution of the ion of copper from human teeth and dental prosthetic crowns in 4% CH(3)COOH during a period of 24 hr at room temperature. The content of the diluted copper in an acetate extract, as well as the overall content of this metal in the samples, was determined by means of a potentiometric stripping analysis. The comparative measurements were carried out using the furnace atomic absorption spectrophotometry technique, which is recommended by the International Standards (ISO 6872:2008; ISO 24234:2004) as a method for quality control of dental-prosthetic material (dental ceramic, metal restorative materials, dental amalgams) in the process of checking for heavy metals. During a 24-hr period in 4% CH(3)COOH at a temperature of 25 degrees C, approximately 72% of the overall copper was released from the tooth. The percentage of the released copper from baby teeth is higher, ranging from 88 to 92%, which is probably a consequence of the bone tissue being in development, its infirmity, and inadequate stability. On these conditions, approximately 72% of the overall copper was released from the dental-ceramic prosthetic crowns.

  6. Corrosion resistance and behavior of construction materials exposed to dilute sulfuric acid at elevated temperatures under static conditions

    SciTech Connect

    Nguyen, D.T.

    1994-10-01

    Laboratory investigation has been undertaken to determine the electrochemical behavior and corrosion resistance of various construction materials in a simulated hydrolysis environment (5 wt % sulfuric acid) at temperatures ranging from 90 to 220C. Tests were performed in an autoclave-type electrochemical cell. The corrosion behavior of the test materials was determined using computer-controlled DC potentiodynamic polarization. Corrosion rates of the test materials were determined using AC impedance techniques. Among the stainless steels tested, only alloy N08026 (Carpenter 20Mo-6) performed satisfactory up to a temperature of 100C. The alloy passivated spontaneously in the environment and corroded at a rate of less than 2 mpy. None of the stainless steels tested could be used at 120{degrees}C or above. A number of nickel-based alloys tested had good corrosion resistance up to 100C, but their corrosion rate exceeded 2 mpy at higher temperatures. Zirconium alloys were satisfactory up to 180C. Only tantalum and a tantalum-niobium alloy were satisfactory up to 220C.

  7. Insights into the Interactions of Amino Acids and Peptides with Inorganic Materials Using Single-Molecule Force Spectroscopy.

    PubMed

    Das, Priyadip; Duanias-Assaf, Tal; Reches, Meital

    2017-03-06

    The interactions between proteins or peptides and inorganic materials lead to several interesting processes. For example, combining proteins with minerals leads to the formation of composite materials with unique properties. In addition, the undesirable process of biofouling is initiated by the adsorption of biomolecules, mainly proteins, on surfaces. This organic layer is an adhesion layer for bacteria and allows them to interact with the surface. Understanding the fundamental forces that govern the interactions at the organic-inorganic interface is therefore important for many areas of research and could lead to the design of new materials for optical, mechanical and biomedical applications. This paper demonstrates a single-molecule force spectroscopy technique that utilizes an AFM to measure the adhesion force between either peptides or amino acids and well-defined inorganic surfaces. This technique involves a protocol for attaching the biomolecule to the AFM tip through a covalent flexible linker and single-molecule force spectroscopy measurements by atomic force microscope. In addition, an analysis of these measurements is included.

  8. Certification of NIST standard reference material 2389a, amino acids in 0.1 mol/L HCl--quantification by ID LC-MS/MS.

    PubMed

    Lowenthal, Mark S; Yen, James; Bunk, David M; Phinney, Karen W

    2010-05-01

    An isotope-dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS) measurement procedure was developed to accurately quantify amino acid concentrations in National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 2389a-amino acids in 0.1 mol/L hydrochloric acid. Seventeen amino acids were quantified using selected reaction monitoring on a triple quadrupole mass spectrometer. LC-MS/MS results were compared to gravimetric measurements from the preparation of SRM 2389a-a reference material developed at NIST and intended for use in intra-laboratory calibrations and quality control. Quantitative mass spectrometry results and gravimetric values were statistically combined into NIST-certified mass fraction values with associated uncertainty estimates. Coefficients of variation (CV) for the repeatability of the LC-MS/MS measurements among amino acids ranged from 0.33% to 2.7% with an average CV of 1.2%. Average relative expanded uncertainty of the certified values including Types A and B uncertainties was 3.5%. Mean accuracy of the LC-MS/MS measurements with gravimetric preparation values agreed to within |1.1|% for all amino acids. NIST SRM 2389a will be available for characterization of routine methods for amino acid analysis and serves as a standard for higher-order measurement traceability. This is the first time an ID LC-MS/MS methodology has been applied for quantifying amino acids in a NIST SRM material.

  9. A Vertical Draining Film with an Insoluble Surfactant and Nonlinear Surface Properties

    NASA Astrophysics Data System (ADS)

    Naire, Shailesh; Braun, Richard; Snow, Steve

    2000-11-01

    The drainage of a thin Newtonian film with an insoluble surfactant is studied theoretically in 1+1 dimensions. Lubrication theory is applied to the thin film, which is suspended vertically from a frame and drains into a bath. Three nonlinear partial differential equations (PDEs) govern the evolution of the film shape, surface velocity and surfactant concentration. The surface viscosity and the surface tension of the films are nonlinear functions of the surface concentration; the functions are of the form defined by Lopez and Hirsa for hemicyanine in water. At high concentrations the effects from surface viscosity and the Marangoni effect become more pronounced. Slow and fast draining limits can still be reached and a Marangoni-driven wave that is very localized may be observed. In some instances, the film surface may even be swept clean over some part of its length. When the surface is swept clean, we expect that a vertical film cannot be made for any useful length of time. This is in agreement with expected behavior when films are made with insoluble surfactants; the surface concentration must be high in order for the film to last. This work has been partially supported by the NSF and Dow Corning.

  10. Gastrointestinal effects associated with soluble and insoluble copper in drinking water.

    PubMed Central

    Pizarro, F; Olivares, M; Araya, M; Gidi, V; Uauy, R

    2001-01-01

    The aim of this study was to determine whether total copper or soluble copper concentration is associated with gastrointestinal signs and symptoms. Forty-five healthy adult women (18-55 years of age), living in Santiago, Chile, ingested tap water with 5 mg/L of copper containing different ratios of soluble copper (copper sulfate) and insoluble copper (copper oxide) over a 9-week period. Three randomized sequences of the different copper ratios (0:5, 1:4, 2:3, 3:2, and 5:0 mg/L) were followed. Subjects recorded their water consumption and gastrointestinal symptoms daily on a special form. Mean water consumption was similar among groups. Serum copper levels, ceruloplasmin, and activities of liver enzymes were within normal limits. No differences were detected between the means of biochemical parameters at the beginning and at the end of the study. Twenty subjects presented gastrointestinal disturbances at least once during the study, 9 suffered diarrhea (with or without abdominal pain and vomiting), and the other 11 subjects reported abdominal pain, nausea, or vomiting. No differences were found in incidence of abdominal pain, nausea, vomiting, and diarrhea regardless of the ratio of copper sulfate to copper oxide. In conclusion, both copper sulfate (a soluble compound) and copper oxide (an insoluble compound) have comparable effects on the induction of gastrointestinal manifestations, implying that similar levels of ionic copper were present in the stomach. PMID:11673125

  11. Nano and microparticle engineering of water insoluble drugs using a novel spray-drying process.

    PubMed

    Schafroth, Nina; Arpagaus, Cordin; Jadhav, Umesh Y; Makne, Sushil; Douroumis, Dennis

    2012-02-01

    In the current study nano and microparticle engineering of water insoluble drugs was conducted using a novel piezoelectric spray-drying approach. Cyclosporin A (CyA) and dexamethasone (DEX) were encapsulated in biodegradable poly(D,L-lactide-co-glycolide) (PLGA) grades of different molecular weights. Spray-drying studies carried out with the Nano Spray Dryer B-90 employed with piezoelectric driven actuator. The processing parameters including inlet temperature, spray mesh diameter, sample flow rate, spray rate, applied pressure and sample concentration were examined in order to optimize the particle size and the obtained yield. The process parameters and the solute concentration showed a profound effect on the particle engineering and the obtained product yield. The produced powder presented consistent and reproducible spherical particles with narrow particle size distribution. Cyclosporin was found to be molecularly dispersed while dexamethasone was in crystalline state within the PLGA nanoparticles. Further evaluation revealed excellent drug loading, encapsulation efficiency and production yield. In vitro studies demonstrated sustained release patterns for the active substances. This novel spray-drying process proved to be efficient for nano and microparticle engineering of water insoluble active substances.

  12. Neuromelanins of human brain have soluble and insoluble components with dolichols attached to the melanic structure.

    PubMed

    Engelen, Mireille; Vanna, Renzo; Bellei, Chiara; Zucca, Fabio A; Wakamatsu, Kazumasa; Monzani, Enrico; Ito, Shosuke; Casella, Luigi; Zecca, Luigi

    2012-01-01

    Neuromelanins (NMs) are neuronal pigments of melanic-lipidic type which accumulate during aging. They are involved in protective and degenerative mechanisms depending on the cellular context, however their structures are still poorly understood. NMs from nine human brain areas were analyzed in detail. Elemental analysis led to identification of three types of NM, while infrared spectroscopy showed that NMs from neurons of substantia nigra and locus coeruleus, which selectively degenerate in Parkinson's disease, have similar structure but different from NMs from brain regions not targeted by the disease. Synthetic melanins containing Fe and bovine serum albumin were prepared to model the natural product and help clarifying the structure of NMs. Extensive nuclear magnetic resonance spectroscopy studies showed the presence of dolichols both in the soluble and insoluble parts of NM. Diffusion measurements demonstrated that the dimethyl sulfoxide soluble components consist of oligomeric precursors with MWs in the range 1.4-52 kDa, while the insoluble part contains polymers of larger size but with a similar composition. These data suggest that the selective vulnerability of neurons of substantia nigra and locus coeruleus in Parkinson's disease might depend on the structure of the pigment. Moreover, they allow to propose a pathway for NM biosynthesis in human brain.

  13. Detergent-insoluble EAAC1/EAAT3 aberrantly accumulates in hippocampal neurons of Alzheimer's disease patients.

    PubMed

    Duerson, Kevin; Woltjer, Randall L; Mookherjee, Paramita; Leverenz, James B; Montine, Thomas J; Bird, Thomas D; Pow, David V; Rauen, Thomas; Cook, David G

    2009-04-01

    Disturbed glutamate homeostasis may contribute to the pathological processes involved in Alzheimer's disease (AD). Once glutamate is released from synapses or from other intracellular sources, it is rapidly cleared by glutamate transporters. EAAC1 (also called EAAT3 or SLC1A1) is the primary glutamate transporter in forebrain neurons. In addition to transporting glutamate, EAAC1 plays other roles in regulating GABA synthesis, reducing oxidative stress in neurons, and is important in supporting neuron viability. Currently, little is known about EAAC1 in AD. To address whether EAAC1 is disturbed in AD, immunohistochemistry was performed on tissue from hippocampus and frontal cortex of AD and normal control subjects matched for age and gender. While EAAC1 immunostaining in cortex appeared comparable to controls, in the hippocampus, EAAC1 aberrantly accumulated in the cell bodies and proximal neuritic processes of CA2-CA3 pyramidal neurons in AD patients. Biochemical analyses showed that Triton X-100-insoluble EAAC1 was significantly increased in the hippocampus of AD patients compared to both controls and Parkinson's disease patients. These findings suggest that aberrant glutamate transporter expression is associated with AD-related neuropathology and that intracellular accumulation of detergent-insoluble EAAC1 is a feature of the complex biochemical lesions in AD that include altered protein solubility.

  14. Vaporization Mechanisms of Water-Insoluble Cs in Ash During Thermal Treatment with Calcium Chloride Addition.

    PubMed

    Jiao, Facun; Iwata, Norie; Kinoshita, Norikazu; Kawaguchi, Masato; Asada, Motoyuki; Honda, Maki; Sueki, Keisuke; Ninomiya, Yoshihiko

    2016-12-20

    The vaporization mechanisms of water-insoluble Cs in raw ash and Cs-doped ash during thermal treatment with CaCl2 addition was systematically examined in a lab-scale electrical heating furnace over a temperature range of 500-1500 °C. The results indicate that the water-insoluble Cs in the ash was associated with aluminosilicate as pollucite. Addition of 10% CaCl2 caused the maximum vaporization ratio of Cs in the raw ash to reach approximately 80% at temperatures higher than 1200 °C, whereas approximately 95% of Cs was vaporized at temperatures higher than 1300 °C when 30% CaCl2 was added. The formation of an intermediate compound, CsCaCl3, through the chemical reaction of Cs with CaCl2 was responsible for Cs vaporization by means of the subsequent decomposition of this intermediate upon the increase in temperature. The indirect chlorination of Cs by the gaseous chlorine released from the decomposition of CaCl2 was insignificant. A high CaCl2 content in the resulting annealed products with 30% CaCl2 addition delayed the decomposition of CsCaCl3 and thus lowered the Cs vaporization ratio compared to that with 10% CaCl2 addition at 900-1250 °C. Thermal treatment with CaCl2 addition is a proposed method to remove Cs from Cs-contaminated incineration ash.

  15. Total, Soluble and Insoluble Oxalate Contents of Ripe Green and Golden Kiwifruit

    PubMed Central

    Nguyễn, Hà Vũ Hồng; Savage, Geoffrey P.

    2013-01-01

    Three bulk samples of two different cultivars of kiwifruit, green (Actinidia deliciosa L.) and golden (Actinidia chinensis L.) were bought ripe, ready to eat from a local market. The aim of the study was to determine the oxalate composition of each of the three fractions of kiwifruit, namely skin, pulp and seeds. The pulp consisted of 90.4% of the edible portion of the two cultivars while the skin and seeds made up a mean of 8.0% and 1.6% respectively. Total oxalate was extracted with 2.0 M HCL at 21 °C for 15 min and soluble oxalates extracted at 21 °C in water for 15 min from each fraction. The total and soluble oxalate compositions of each fraction were determined using ion exchange HPLC chromatography. The pulp of golden kiwifruit contained lower amounts of total oxalates (15.7 vs. 19.3 mg/100 g FW) and higher amounts of soluble oxalates (8.5 vs. 7.6 mg/100 g FW) when compared to the green cultivar. The skin of the green cultivar contained lower levels of insoluble oxalates (36.9 vs. 43.6 mg/100 g FW), while the seeds of the green cultivar contained higher levels of insoluble oxalates 106.7 vs. 84.7 mg/100 g FW.

  16. [Soluble and insoluble dietary fiber in cereals and legumes cultivated in Chile].

    PubMed

    Pak, N; Ayala, C; Vera, G; Pennacchiotti, I; Araya, H

    1990-03-01

    Insoluble, soluble and total dietary fiber (DF) were determined in 35 varieties of certified whole seeds (without processing) of cereals (rice, oat, rye, and wheat) and legumes (pea, cowpea, beans, chikpea, lentil and lupine). The enzymatic method of Asp, Johansson and Siljestrom was used, with modifications in relation to time of incubation with alpha amylase, filtration system and volumes of the filtrates. Results were expressed as g/100 g dry weight. Total DF for cereals showed a range from 10.1 (wheat var. Chasqui) to 22.2 (rice var Quella). Rye, var. Tetra Baer and oats var. Pony Baer presented the highest soluble fiber content (3.3 and 3.9, respectively). In legumes, total DF fluctuated between 12.7 (pea, var. yellow) and 36.6 (lupine, var. Multolupa). Bean, var. Pinto INIA and lupine var. Multolupa presented the highest soluble fiber values (5.8 for both). Based on the results of this research work, it might be concluded that great variation exists in regard to the amount of total soluble and insoluble DF in cereals and legumes, a fact which impedes generalization as to its content in each food item.

  17. Functional and physiological properties of total, soluble, and insoluble dietary fibres derived from defatted rice bran.

    PubMed

    Daou, Cheickna; Zhang, Hui

    2014-12-01

    Enzymatic- gravimetric method was used to obtain three fractions of dietary from defatted rice bran. The functional and physiological properties such as viscosity, cation exchange capacity (CEC), and glucose dialysis retardation index (GDRI), cholesterol and bile salt adsorption capacity of the resultant fractions were evaluated. Insoluble dietary fibre (IDF) and soluble dietary fibre (SDF) when compared showed that SDF exhibited significantly (p < 0.05) higher viscosity (2.35 mPa.s), greater GDRI value (17.65 %) at 60 min and significantly lowered concentration of cholesterol at pH 7 (29.90 %, p < 0.05). However IDF showed the highest CEC and its adsorption capacity of bile salt was higher than SDF (18.20 % vs. 13.76 %; p < 0.05), while CEC and cholesterol absorption capacity of TDF were similar to SDF. These properties indicate that rice bran soluble, insoluble and total fibres are functional ingredients which can be added to various food products and dietetic, low-calorie high-fiber foods to enhance their nutraceutical properties and health benefits.

  18. Characterisation of detergent-insoluble membranes in pollen tubes of Nicotiana tabacum (L.)

    PubMed Central

    Moscatelli, Alessandra; Gagliardi, Assunta; Maneta-Peyret, Lilly; Bini, Luca; Stroppa, Nadia; Onelli, Elisabetta; Landi, Claudia; Scali, Monica; Idilli, Aurora Irene; Moreau, Patrick

    2015-01-01

    ABSTRACT Pollen tubes are the vehicle for sperm cell delivery to the embryo sac during fertilisation of Angiosperms. They provide an intriguing model for unravelling mechanisms of growing to extremes. The asymmetric distribution of lipids and proteins in the pollen tube plasma membrane modulates ion fluxes and actin dynamics and is maintained by a delicate equilibrium between exocytosis and endocytosis. The structural constraints regulating polarised secretion and asymmetric protein distribution on the plasma membrane are mostly unknown. To address this problem, we investigated whether ordered membrane microdomains, namely membrane rafts, might contribute to sperm cell delivery. Detergent insoluble membranes, rich in sterols and sphingolipids, were isolated from tobacco pollen tubes. MALDI TOF/MS analysis revealed that actin, prohibitins and proteins involved in methylation reactions and in phosphoinositide pattern regulation are specifically present in pollen tube detergent insoluble membranes. Tubulins, voltage-dependent anion channels and proteins involved in membrane trafficking and signalling were also present. This paper reports the first evidence of membrane rafts in Angiosperm pollen tubes, opening new perspectives on the coordination of signal transduction, cytoskeleton dynamics and polarised secretion. PMID:25701665

  19. An automatic collector to monitor insoluble atmospheric deposition: application for mineral dust deposition

    NASA Astrophysics Data System (ADS)

    Laurent, B.; Losno, R.; Chevaillier, S.; Vincent, J.; Roullet, P.; Bon Nguyen, E.; Ouboulmane, N.; Triquet, S.; Fornier, M.; Raimbault, P.; Bergametti, G.

    2015-07-01

    Deposition is one of the key terms of the mineral dust cycle. However, dust deposition remains poorly constrained in transport models simulating the atmospheric dust cycle. This is mainly due to the limited number of relevant deposition measurements. This paper aims to present an automatic collector (CARAGA), specially developed to sample the total (dry and wet) atmospheric deposition of insoluble dust in remote areas. The autonomy of the CARAGA can range from 25 days to almost 1 year depending on the programmed sampling frequency (from 1 day to 2 weeks respectively). This collector is used to sample atmospheric deposition of Saharan dust on the Frioul islands in the Gulf of Lions in the Western Mediterranean. To quantify the mineral dust mass in deposition samples, a weighing and ignition protocol is applied. Almost 2 years of continuous deposition measurements performed on a weekly sampling basis on Frioul Island are presented and discussed with air mass trajectories and satellite observations of dust. Insoluble mineral deposition measured on Frioul Island was 2.45 g m-2 for February to December 2011 and 3.16 g m-2 for January to October 2012. Nine major mineral deposition events, measured during periods with significant MODIS aerosol optical depths, were associated with air masses coming from the southern Mediterranean Basin and North Africa.

  20. Polypropylene Glycol-Silver Nanoparticle Composites: A Novel Anticorrosion Material for Aluminum in Acid Medium

    NASA Astrophysics Data System (ADS)

    Solomon, Moses M.; Umoren, Saviour A.; Israel, Aniekemeabasi U.; Ebenso, Eno E.

    2015-11-01

    Admixture of polypropylene glycol and 1 mM AgNO3 together with natural honey as reducing and stabilizing agent was employed to prepare in situ polypropylene glycol/silver nanoparticle (PPG/AgNPs) composite. The prepared PPG/AgNPs composite was characterized by UV-Vis spectroscopy, FTIR, XRD, and EDS, while the morphology of the Ag nanoparticles in the composite was obtained by TEM. TEM results revealed that the Ag nanoparticles were spherical in shape. The anticorrosion property of PPG/AgNPs composite was examined by electrochemical, weight loss, SEM, EDS, and water contact angle measurements. Results obtained show that PPG/AgNPs are effective in retarding the dissolution of Al in an acid-induced corrosive environment. Inhibition efficiency increased with the increasing composite concentration but decreased with the increasing temperature. Potentiodynamic polarization results revealed that PPG/AgNPs functions as a mixed-type corrosion inhibitor. The adsorption of the composite onto Al surface was found to follow El-Awady et al. adsorption isotherm model. SEM, EDS, and water contact angle results confirmed the adsorption of PPG/AgNPs films onto Al surface.

  1. Preparation and research of nano-scale europium (III)-pyromellitic acid powder luminescent material.

    PubMed

    Zhenfeng, Cui; Huijuan, Ren; Chun, Zheng; Fenghua, Chen; Guangyan, Hong

    2010-03-01

    The nanoscale luminescent complex of europium (III)-pyromellitic acid was synthesized successfully in the polyvinylpyrrolidone (PVP) matrix by a co-precipitation method. The chemical formula of the synthesized complex was speculated to be PVP/Eu4/3L x 3H2O by elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and Fourier-transform infrared spectroscopy (FT-IR). The X-ray diffraction (XRD) pattern of PVP/Eu4/3L x 3H2O indicated that it was a new crystalline complex since the diffraction angle, diffraction intensity, and distance of the crystal plane were all different from those of the ligand. It is proved by the thermogravimetric curve that the synthesized nanoscale luminescent complex was stable, ranging from ambient temperature to 479 degrees C in air. The transmission electron microscopy (TEM) image showed that the complex was nanoparticles. The synthesized complex emitted the characteristic red fluorescence of Eu(III) ions under ultraviolet excitation by the photoluminescence analyses. For example, the emission peaks of PVP/Eu4/3L x 3H2O at 578, 591, 612, and 694 nm using 322 nm as exciting wavelength are assigned to the 5D0 --> 7F0, 5D0 --> 7F1, 5D0 --> F2, and 5D0 --> 7F4 electron transitions of the Eu3+ ions, respectively.

  2. Material characterization of poly-lactic acid shelled ultrasound contrast agent and their dynamics

    NASA Astrophysics Data System (ADS)

    Paul, Shirshendu; Russakow, Daniel; Rodgers, Tyler; Sarkar, Kausik; Cochran, Michael; Wheatley, Margaret

    2011-11-01

    Micron-size gas bubbles encapsulated with lipids and proteins are used as contrast enhancing agents for ultrasound imaging. Biodegradable polymer poly-lactic acid (PLA) has recently been suggested as a possible means of encapsulation. Here, we report in vitro measurement of attenuation and scattering of ultrasound through an emulsion of PLA agent as well as theoretical modeling of the encapsulated bubble dynamics. The attenuation measured with three different transducers of central frequencies 2.25, 3.5 and 5 MHz, shows a peak around 2-3 MHz. These bubbles also show themselves to possess excellent scattering characteristics including strong non-linear response that can be used for harmonic and sub-harmonic contrast imaging. Our recently developed interfacial rheological models are applied to describe the dynamics of these bubbles; rheological model properties are estimated using measured attenuation data. The model is then applied to predict nonlinear scattered response, and the prediction is compared against experimental observation. Partially supported by NSF and NIH.

  3. Poly(lactic acid)/TiO₂ nanocomposites as alternative biocidal and antifungal materials.

    PubMed

    Fonseca, Carmen; Ochoa, Almudena; Ulloa, Maria Teresa; Alvarez, Eduardo; Canales, Daniel; Zapata, Paula A

    2015-12-01

    Poly(lactic acid) (PLA) composites with titanium oxide (TiO2) ~10-nm nanoparticles were produced by the melting process and their main properties were evaluated. The nanoparticles are homogeneously dispersed in the matrix with a low degree of agglomeration, as seen by transmission electron microscopy (TEM). The crystallinity temperature increased ~12% when 5 wt.% of TiO2 was added, showing that the nanoparticles acted as nucleating agents this trend was confirmed by optical images. The elastic modulus increased ~54% compared to neat PLA at 5 wt.% of nanoparticles. Despite these improvements, PLA/TiO2 nanocomposites showed lower shear viscosity than neat PLA, possibly reflecting degradation of the polymer due to the particles. Regarding biocidal properties, after 2h of contact the PLA/TiO2 composites with 8 wt.% TiO2 showed a reduction of Escherichia coli colonies of ~82% under no UVA irradiation compared to pure PLA. This biocidal characteristic can be increased under UVA irradiation, with nanocomposites containing 8 wt.% TiO2 killing 94% of the bacteria. The PLA/TiO2 nanocomposites with 8 wt.% were also 99.99% effective against Aspergillus fumigatus under the UVA irradiation.

  4. Determination of the non-ionic detergent insolubility and phosphoprotein associations of glycosylphosphatidylinositol-anchored proteins expressed on T cells.

    PubMed Central

    Solomon, K R; Mallory, M A; Finberg, R W

    1998-01-01

    Glycosylphosphatidylinositol (GPI)-anchored proteins are poorly solublized in non-ionic detergents such as Triton X-100 and Nonidet P40, but are easily solublized by detergents with high critical micelle concentrations such as octylglucoside. This solubility profile has been suggested to be due to the localization of GPI-anchored proteins to lipid microdomains rich in cholesterol and sphingolipids. Additionally, GPI-anchored proteins expressed on haemopoietic cells have been shown to associate with src-family tyrosine kinases and heterotrimeric G proteins. Despite these observations, the non-ionic detergent insolubility of GPI-anchored proteins on haemopoietic cells has not been quantified nor has a relationship between the non-ionic detergent insolubility of these proteins and their association with signal-transduction molecules been identified. Here we show that GPI-anchored proteins found on T-cell tumours and activated T cells, although significantly more insoluble then transmembrane proteins, are not uniform in their detergent insolubility. Whereas CD59 was between 4% and 13% soluble, CD48 was between 13% and 25% soluble, CD55 was between 20% and 30% soluble, and CD109 was between 34% and 75% soluble. The ability of these GPI-anchored proteins to associate with phosphoproteins was correlated with their detergent insolubility: the more detergent-insoluble that a GPI-anchored protein was, the greater the level of phosphoprotein associations. These experiments reveal a relationship between non-ionic detergent insolubility and association with signal-transduction molecules and suggest a cause-and-effect relationship between these two properties. In total, these experiments support the hypothesis that the association of GPI-anchored proteins with signalling molecules is due to their sorting to lipid microdomains. PMID:9716490

  5. Determination of the non-ionic detergent insolubility and phosphoprotein associations of glycosylphosphatidylinositol-anchored proteins expressed on T cells.

    PubMed

    Solomon, K R; Mallory, M A; Finberg, R W

    1998-09-01

    Glycosylphosphatidylinositol (GPI)-anchored proteins are poorly solublized in non-ionic detergents such as Triton X-100 and Nonidet P40, but are easily solublized by detergents with high critical micelle concentrations such as octylglucoside. This solubility profile has been suggested to be due to the localization of GPI-anchored proteins to lipid microdomains rich in cholesterol and sphingolipids. Additionally, GPI-anchored proteins expressed on haemopoietic cells have been shown to associate with src-family tyrosine kinases and heterotrimeric G proteins. Despite these observations, the non-ionic detergent insolubility of GPI-anchored proteins on haemopoietic cells has not been quantified nor has a relationship between the non-ionic detergent insolubility of these proteins and their association with signal-transduction molecules been identified. Here we show that GPI-anchored proteins found on T-cell tumours and activated T cells, although significantly more insoluble then transmembrane proteins, are not uniform in their detergent insolubility. Whereas CD59 was between 4% and 13% soluble, CD48 was between 13% and 25% soluble, CD55 was between 20% and 30% soluble, and CD109 was between 34% and 75% soluble. The ability of these GPI-anchored proteins to associate with phosphoproteins was correlated with their detergent insolubility: the more detergent-insoluble that a GPI-anchored protein was, the greater the level of phosphoprotein associations. These experiments reveal a relationship between non-ionic detergent insolubility and association with signal-transduction molecules and suggest a cause-and-effect relationship between these two properties. In total, these experiments support the hypothesis that the association of GPI-anchored proteins with signalling molecules is due to their sorting to lipid microdomains.

  6. Synthesis of a novel electrode material containing phytic acid-polyaniline nanofibers for simultaneous determination of cadmium and lead ions.

    PubMed

    Huang, Hui; Zhu, Wencai; Gao, Xiaochun; Liu, Xiuyu; Ma, Houyi

    2016-12-01

    The development of nanostructured conducting polymers based materials for electrochemical applications has attracted intense attention due to their environmental stability, unique reversible redox properties, abundant electron active sites, rapid electron transfer and tunable conductivity. Here, a phytic acid doped polyaniline nanofibers based nanocomposite was synthesized using a simple and green method, the properties of the resulting nanomaterial was characterized by electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). A glassy carbon electrode modified by the nanocomposite was evaluated as a new platform for the simultaneous detection of trace amounts of Cd(2+) and Pb(2+) using differential pulse anodic stripping voltammetry (DPASV). The synergistic contribution from PANI nanofibers and phytic acid enhances the accumulation efficiency and the charge transfer rate of metal ions during the DPASV analysis. Under the optimal conditions, good linear relationships were obtained for Cd(2+) in a range of 0.05-60 μg L(-1), with the detection limit (S/N = 3) of 0.02 μg L(-1), and for Pb(2+) in a range of 0.1-60 μg L(-1), with the detection limit (S/N = 3) of 0.05 μg L(-1). The new electrode was successfully applied to real water samples for simultaneous detection of Cd(2+) and Pb(2+) with good recovery rates. Therefore, the new electrode material may be a capable candidate for the detection of trace levels of heavy metal ions.

  7. Temperature shifts for extraction and purification of zygomycetes chitosan with dilute sulfuric acid.

    PubMed

    Zamani, Akram; Edebo, Lars; Niklasson, Claes; Taherzadeh, Mohammad J

    2010-08-13

    The temperature-dependent hydrolysis and solubility of chitosan in sulfuric acid solutions offer the possibility for chitosan extraction from zygomycetes mycelia and separation from other cellular ingredients with high purity and high recovery. In this study, Rhizomucor pusillus biomass was initially extracted with 0.5 M NaOH at 120 °C for 20 min, leaving an alkali insoluble material (AIM) rich in chitosan. Then, the AIM was subjected to two steps treatment with 72 mM sulfuric acid at (i) room temperature for 10 min followed by (ii) 120 °C for 45 min. During the first step, phosphate of the AIM was released into the acid solution and separated from the chitosan-rich residue by centrifugation. In the second step, the residual AIM was re-suspended in fresh 72 mM sulfuric acid, heated at 120 °C and hot filtered, whereby chitosan was extracted and separated from the hot alkali and acid insoluble material (HAAIM). The chitosan was recovered from the acid solution by precipitation at lowered temperature and raised pH to 8-10. The treatment resulted in 0.34 g chitosan and 0.16 g HAAIM from each gram AIM. At the start, the AIM contained at least 17% phosphate, whereas after the purification, the corresponding phosphate content of the obtained chitosan was just 1%. The purity of this chitosan was higher than 83%. The AIM subjected directly to the treatment with hot sulfuric acid (at 120 °C for 45 min) resulted in a chitosan with a phosphate impurity of 18.5%.

  8. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    NASA Astrophysics Data System (ADS)

    Gomes, Ruth; Dutta, Saikat; Bhaumik, Asim

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state 13C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N2 sorption, HR-TEM, and NH3 temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  9. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    SciTech Connect

    Gomes, Ruth; Bhaumik, Asim; Dutta, Saikat

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state {sup 13}C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N{sub 2} sorption, HR-TEM, and NH{sub 3} temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  10. Physical state and acidity of inorganic sulfate can regulate the production of secondary organic material from isoprene photooxidation products.

    PubMed

    Kuwata, Mikinori; Liu, Yingjun; McKinney, Karena; Martin, Scot T

    2015-02-28

    The production of secondary organic material (SOM) by the reactive uptake of isoprene photooxidation products was investigated using partially to wholly neutralized sulfuric acid particles. The experiments were performed at a relative humidity (RH) of <5% and a temperature of 20 °C. The extent X of neutralization was adjusted from that of sulfuric acid (X = 0) to that of ammonium sulfate (X = 1). Significant SOM production was observed only for X < 0.7. The threshold of 0.7 corresponded to the transition point of the sulfate particles from aqueous to solid for <5% RH. The phase transition of inorganic sulfate therefore regulated the particle-phase reactions that produce isoprene SOM, at least for the investigated conditions. For aqueous particles, a decreasing extent of neutralization was associated with increasing production of SOM, including increased production of oligomers and organosulfates. These results can underpin treatments of phase-dependent SOM production within chemical transport models, thereby improving the accuracy of simulations of biogenic-anthropogenic interactions in the atmosphere and the associated impacts of aerosol particles on climate and air quality.

  11. Influence of carbons on the structure of the negative active material of lead-acid batteries and on battery performance

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Nikolov, P.; Rogachev, T.

    It has been established that addition of carbon additives to the lead negative active material (NAM) of lead-acid batteries increase battery charge acceptance in hybrid electric vehicle mode of operation. The present work studies three types of activated carbons and two types of carbon blacks with the aim to evaluate their efficiency in improving the charge acceptance of lead-acid batteries. It has been established that the size of carbon particles and their affinity to lead are essential. If carbon particles are of nanosizes, they are incorporated into the bulk of the skeleton branches of NAM and may thus increase the latter's ohmic resistance. Their content in NAM should not exceed 0.2-0.5 wt.%. At this loading level, carbon grains are adsorbed only on the surface of NAM contributing to the increase of its specific surface area and thus improving its charge acceptance. When carbon particles are of micron sizes and have high affinity to lead, they are integrated into the skeleton structure of NAM as a structural component and act as super-capacitors, i.e. electric charges are concentrated in them and then the current is distributed along the adjacent branches of the lead skeleton with the lowest ohmic resistance. This eventually improves the charge acceptance of the negative battery plates.

  12. Synthesis and characterization of a material derived from 4-mercaptobenzoic acid: A novel platform for oligonucleotide immobilization.

    PubMed

    Alves, Rafael da Fonseca; da Silva, Amanda Gonçalves; Ferreira, Lucas Franco; Franco, Diego Leoni

    2017-04-01

    This paper reports the electrochemical modification of pencil carbon graphite electrodes with a polymeric material derived from 4-mercaptobenzoic acid. Acidic solutions (pH 0 and 5.02) yielded an insulating polymeric film with anionic permselective properties. Scanning Electron Microscopy (SEM) analysis showed a complete coverage of the carbon graphite electrodes with a laminar-like polymeric structure. Different characterization studies indicate that the carboxyl group remained unchanged since the absorbance peak and oxidation potential did not change with the increase in pH at the pKa accounting for the carboxyl/carboxylate redox transition. The functionalized matrix was activated using carbodiimide, succinimide and an amine-modified oligonucleotide. The immobilization and hybridization processes were successfully verified using the redox electroactive indicator methylene blue, where better electrochemical signals were obtained when compared with the traditional self-assembled monolayer system. The selectivity of the system was verified using a noncomplementary target where no significant difference in electric current was observed when compared to the system containing only the probe. The method showed a good linear correlation coefficient (r(2)=0.9915), low limit of detection (1.17nmolL(-1)), and an acceptable precision (RSD=2.75%). The proposed method is suitable for further studies using different sequences of oligonucleotides.

  13. Monitoring changes in acid value, total polar material, and antioxidant capacity of oils used for frying chicken.

    PubMed

    Song, JuHee; Kim, Mi-Ja; Kim, Young-Jun; Lee, JaeHwan

    2017-04-01

    Oxidation products and tocol homologues were monitored in oils during chicken frying to determine the discarding point of highly used frying oils. Oils were heated without chicken for 170h while chicken frying was performed 130 cycles at 180°C. As heating time and frying cycles increased, all oxidation parameters including acid value, total polar materials (TPM), conjugated dienoic acid (CDA), and p-anisidine values (p-AV) increased significantly (p<0.05). γ-Tocopherol and γ-tocotrienol had the lowest stability in oils during heating or frying processes compared to other tocol homologues. TPM values over 24% were obtained after about 109h for heated oil and 100 cycles for oils used to fry chicken. A decrease of 2,2-diphenyl-1-picrylhydrazyl (DPPH) in isooctane and methanol was highly correlated with the formation of TPM in oils during the frying process. Both DPPH loss and TPM values could be applied to determine the discarding points of highly used frying oils.

  14. Poly(citric acid)-block-poly(ethylene glycol) copolymers--new biocompatible hybrid materials for nanomedicine.

    PubMed

    Naeini, Ashkan Tavakoli; Adeli, Mohsen; Vossoughi, Manouchehr

    2010-08-01

    Linear-dendritic ABA triblock copolymers containing poly(ethylene glycol) (PEG) as B block and hyperbranched poly(citric acid) (PCA) as A blocks were synthesized through polycondensation. The molecular self-assembly of synthesized PCA-PEG-PCA copolymers in water led to formation of nanoparticles and fibers in different sizes and shapes depending on the time and size of PCA blocks. Ten days after dissolving PCA-PEG-PCA copolymers in water, the size of fibers had reached several millimeters. Mixing a water solution of fluorescein as a small guest molecule and PCA-PEG-PCA copolymers led to the encapsulation of fluorescein by products of molecular self-assembly. To investigate their potential application in nanomedicine and to understand the limitations and capabilities of these materials as nanoexcipients in biological systems, different types of short-term in vitro cytotoxicity experiments on the HT1080 cell line (human fibrosarcoma) and hemocompatibility tests were performed. From the clinical editor: This manuscript investigates the potentials of linear-dendritic ABA triblock copolymers containing poly(ethylene glycol) (PEG) as B block and hyperbranched poly(citric acid) (PCA) as A blocks for future applications in nanomedicine.

  15. Effect of plate preparation on active-material utilization and cycleability of positive plates in automotive lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Ozgun, H.; Lam, L. T.; Rand, D. A. J.; Bhargava, S. K.

    The power demands from automotive lead/acid batteries are rising steadily with the increasing number of electronic accessories that are being fitted to modern vehicles. In order to meet new levels of performance, automotive batteries have been redesigned to use low-ohmic microporous separators, as well as thinner plates (to increase the number of plates per cell) that are made with a low paste density. This approach, however, has led to a separate problem, namely, an appreciable reduction in battery service life. To redress this situation, a research programme has been implemented in our laboratories to examine, in detail, the effect of plate preparation on the active-material utilization and cycleability of automotive positive plates with grids made from low-antimony alloy. The cycleability is evaluated in terms of repetitive reserve-capacity. The results suggest that a paste formula with a combination of high density and low acid-to-oxide ratio is the most appropriate technology for the production of the thin positive plates that are required in advanced designs of automotive batteries.

  16. The effect of ascorbic acid on the nature and production of collagen and elastin by rat smooth-muscle cells.

    PubMed Central

    de Clerck, Y A; Jones, P A

    1980-01-01

    1. The effects of various concentrations of ascorbic acid on the quality and quantity of the insoluble extracellular matrices produced by two strains of cultured rat smooth-muscle cells were studied. 2. Ascorbic acid was necessary for the appearance of insoluble collagen in the extracellular matrix. 3. Secretion of soluble collagen continued in the absence of ascorbic acid, but this soluble collagen was markedly underhydroxylated. 4. The amount of insoluble collagen present in the matrix was directly related to the ascorbic acid concentration. 5. The insoluble collagen that appeared in the matrix under conditions where ascorbic acid was limiting was no more than 7% underhydroxylated. 6. In contrast, the amount of insoluble elastin produced was inversely proportional to the ascorbic acid concentration. 7. The elastin produced in the absence of ascorbic acid had the expected amino acid composition, but hydroxyproline was absent. 8. The hydroxyproline content of elastin was also directly dependent on the ascorbic acid concentration. 9. Ascorbic acid had variable effects on the quantity of glycoprotein(s) present in the matrix. 10. The appearance of insoluble collagen in the extracellular matrices produced by cultured human fibroblasts and calf endothelial cells was also completely dependent on the presence of ascorbic acid. PMID:7370010

  17. Corrosion investigations on zircaloy-4 and titanium dissolver materials for MOX fuel dissolution in concentrated nitric acid containing fluoride ions

    NASA Astrophysics Data System (ADS)

    Jayaraj, J.; Krishnaveni, P.; Krishna, D. Nanda Gopala; Mallika, C.; Mudali, U. Kamachi

    2016-05-01

    Aqueous reprocessing of plutonium-rich mixed oxide fuels require fluoride as a dissolution catalyst in boiling nitric acid for an effective dissolution of the spent fuel. High corrosion rates were obtained for the candidate dissolver materials zircaloy-4 (Zr-4) and commercial pure titanium (CP-Ti grade 2) in boiling 11.5 M HNO3 + 0.05 M NaF. Complexing the fluoride ions either with Al(NO3)3 or ZrO(NO3)2 aided in decreasing the corrosion rates of Zr-4 and CP-Ti. From the obtained corrosion rates it is concluded that CP-Ti is a better dissolver material than Zr-4 for extended service life in boiling 11.5 M HNO3 + 0.05 M NaF, when complexed with 0.15 M ZrO(NO3)2. XPS analysis confirmed the presence of TiO2 and absence of fluoride on the surface of CP-Ti samples, indicating that effective complexation had occurred in solution leading to passivation of the metal and imparting high corrosion resistance.

  18. Preparation and characterization of trihydroxamic acid functionalized carbon materials for the removal of Cu(II) ions from aqueous solution

    NASA Astrophysics Data System (ADS)

    Godino-Salido, M. Luz; Santiago-Medina, Antonio; López-Garzón, Rafael; Gutiérrez-Valero, María D.; Arranz-Mascarós, Paloma; López de la Torre, M. Dolores; Domingo-García, María; López-Garzón, F. Javier

    2016-11-01

    The main objective of this study is to prepare and characterize two functionalizated carbon materials with enhanced adsorptive properties for Cu(II). Thus, two novel hybrid materials have been prepared by a non-covalent functionalization method based on the adsorption of a pyrimidine-desferrioxamine-B conjugate compound (H4L) on two activated carbons, ACs (labelled Merck and F). The adsorption of H4L on the ACs is pH-dependent and highly irreversible. This is due to strong π-π interactions between the arene centers of the ACs and the pyrimidine moiety of H4L. The textural characterization of the AC/H4L hybrids shows large decreases of their surface areas. Thus the values of Merck and F are 1031 and 1426 m2/g respectively, while these of Merck/H4L and F/H4L hybrids are 200 and 322 m2/g. An important decrease in the micropore volumes is also found, due to the blockage of narrow porosity produced by the adsorption of H4L molecules. The ACs/H4L hybrids show larger adsorption capacities for Cu(II) (0.105(4) and 0.13(2) mmol/g, at pH 2.0, and 0.20(3) and 0.242(9) mmol/g, at pH 5.5, for Merck/H4L and F/H4L, respectively) than those of the ACs (0.024(6) and 0.096(9) mmol/g, at pH 2.0, and 0.10(2) and 0.177(8) mmol/g, at pH 5.5, for Merck and F respectively), which is explained on the basis of the complexing ability of the trihydroxamic acid functions. The desorption of Cu(II) from the ACs/H4L/Cu(II) materials in acid solution allows the regeneration of most active sites (78.5% in the case of Merck/H4L/Cu(II) and 83.0% in the case of F/H4L/Cu(II)).

  19. Sorption of estrogens and pesticides from aqueous solution by a humic acid and raw and processed plant materials

    NASA Astrophysics Data System (ADS)

    Loffredo, Elisabetta; Taskin, Eren

    2016-04-01

    The huge number of organic contaminants released in water as a consequence of anthropogenic activities have detrimental effects to environmental systems and human health. Industrial products and byproducts, pharmaceuticals, pesticides, detergents and so on impose increasing costs for wastewater decontamination. Adsorption techniques can be successfully used for the treatment of wastewaters to remove contaminants of various nature. Humic acids (HA) have well-known adsorptive capacities towards hydrophilic and, especially, hydrophobic compounds. In the recent years, alternative low-cost adsorbents, especially originated from agricultural wastes and food industries residues, such as wood chips, almond and coconut shells, peanut and rice husks, are under investigation. Biochar is also considered a promising and relatively low-cost adsorbent, even if there are still knowledge gaps about the influence of feedstock type, pyrolysis conditions, physical and chemical properties on its potential and safe use. In the present work, a HA from a green compost was used along with three other materials of plant origin to remove two estrogens, 4-tert-octylphenol and 17-β-estradiol, and two pesticides, carbaryl and fenuron, from an aqueous solution. The four molecules were spiked in water each at a concentration of 1 mg L-1. The materials were: a biochar obtained from 100% red spruce pellet pyrolysed at 550 °C, spent coffee grounds and spent tea leaves. Kinetics curves and adsorption isotherms studies were performed using a batch equilibrium method. Adsorption data obtained for each compound were fitted to a linear equation and non-linear Freundlich and Langmuir models. Kinetics data of the four compounds onto all adsorbents showed an initial very rapid adsorption which was completed in few hours when it reached equilibrium. The two estrogens were adsorbed onto all materials more quickly than the two less hydrophobic pesticides. Significant differences among adsorbents and the

  20. The use of nanometer tetrabasic lead sulfate as positive active material additive for valve regulated lead-acid battery

    NASA Astrophysics Data System (ADS)

    Lang, Xiaoshi; Wang, Dianlong; Hu, Chiyu; Tang, Shenzhi; Zhu, Junsheng; Guo, Chenfeng

    2014-12-01

    Conventional tetrabasic lead sulfate used as positive active material additive shows the results of the low effective lead dioxide conversion rate due to the large grain size and crossed the crystal structure. In this paper, we study on a type of nanometer tetrabasic lead sulfate. Through the XRD and SEM test and Material Studio software calculation, the purity of tetrabasic lead sulfate is very high, the grain size of the nanometer 4BS is almost unanimous, and can be controlled below 200 nm. When charged and discharged in 1.75 V-2.42 V with the current density of 40 mA g-1, 80 mA g-1 and 160 mA g-1, the effective lead dioxide conversion rate of nanometer 4BS after formation can achieve to 83.48%, 71.42%, and 66.96%. Subsequently, the nanometer 4BS as additive is added to positive paste of lead-acid battery. When the batteries are tested galvanostatically between 1.75 V and 2.42 V at 0.25 C charge and 0.5 C discharge rates at room temperature. The ratio of adding nanometer 4BS is 0%, 1% and 4% and the initial discharge specific capacities are 60 mAh g-1, 65 mAh g-1 and 68 mAh g-1. After 80 cycles, the initial discharge capacity of positive active material with 1% nanometer 4BS decreased less than 10%, while adding 4% nanometer 4BS, the initial discharge capacity doesn't decrease obviously.

  1. Effect of chemical composition on corneal cellular response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid.

    PubMed

    Lai, Jui-Yang

    2013-10-01

    Characterization of corneal cellular response to hydrogel materials is an important issue in ophthalmic applications. In this study, we aimed to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and material compatibility towards corneal stromal and endothelial cells. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Results of electrokinetic measurements showed that an increase in absolute zeta potential of photopolymerized membranes is observed with increasing the volume ratios of AAc/HEMA. Following 4 days of incubation with various hydrogels, the primary rabbit corneal stromal and endothelial cell cultures were examined for viability, proliferation, and pro-inflammatory gene expression. The samples prepared from the solution mixture containing 0-10 vol.% AAc displayed good cytocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the decreased viability, inhibited proliferation, and stimulated inflammation were noted in both cell types, probably due to the stronger charge-charge interactions. On the other hand, the ionic pump function of corneal endothelial cells exposed to photopolymerized membranes was examined by analyzing the Na(+),K(+)-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of material samples having higher anionic charge density (i.e., zeta potential of -38 to -56 mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal stromal and endothelial cell responses to polymeric biomaterials.

  2. Immobilization of Lactobacillus rhamnosus in mesoporous silica-based material: An efficiency continuous cell-recycle fermentation system for lactic acid production.

    PubMed

    Zhao, Zijian; Xie, Xiaona; Wang, Zhi; Tao, Yanchun; Niu, Xuedun; Huang, Xuri; Liu, Li; Li, Zhengqiang

    2016-06-01

    Lactic acid bacteria immobilization methods have been widely used for lactic acid production. Until now, the most common immobilization matrix used is calcium alginate. However, Ca-alginate gel disintegrated during lactic acid fermentation. To overcome this deficiency, we developed an immobilization method in which Lactobacillus rhamnosus cells were successfully encapsulated into an ordered mesoporous silica-based material under mild conditions with a high immobilization efficiency of 78.77% by using elemental analysis. We also optimized the cultivation conditions of the immobilized L. rhamnosus and obtained a high glucose conversion yield of 92.4%. Furthermore, L. rhamnosus encapsulated in mesoporous silica-based material exhibited operational stability during repeated fermentation processes and no decrease in lactic acid production up to 8 repeated batches.

  3. Brain Targeting of a Water Insoluble Antipsychotic Drug Haloperidol via the Intranasal Route Using PAMAM Dendrimer.

    PubMed

    Katare, Yogesh K; Daya, Ritesh P; Sookram Gray, Christal; Luckham, Roger E; Bhandari, Jayant; Chauhan, Abhay S; Mishra, Ram K

    2015-09-08

    Delivery of therapeutics to the brain is challenging because many organic molecules have inadequate aqueous solubility and limited bioavailability. We investigated the efficiency of a dendrimer-based formulation of a poorly aqueous soluble drug, haloperidol, in targeting the brain via intranasal and intraperitoneal administration. Aqueous solubility of haloperidol was increased by more than 100-fold in the developed formulation. Formulation was assessed via different routes of administration for behavioral (cataleptic and locomotor) responses, and for haloperidol distribution in plasma and brain tissues. Dendrimer-based formulation showed significantly higher distribution of haloperidol in the brain and plasma compared to a control formulation of haloperidol administered via intraperitoneal injection. Additionally, 6.7 times lower doses of the dendrimer-haloperidol formulation administered via the intranasal route produced behavioral responses that were comparable to those induced by haloperidol formulations administered via intraperitoneal injection. This study demonstrates the potential of dendrimer in improving the delivery of water insoluble drugs to brain.

  4. Thermodynamically consistent description of the hydrodynamics of free surfaces covered by insoluble surfactants of high concentration

    NASA Astrophysics Data System (ADS)

    Thiele, Uwe; Archer, Andrew J.; Plapp, Mathis

    2012-10-01

    In this paper, we propose several models that describe the dynamics of liquid films which are covered by a high concentration layer of insoluble surfactant. First, we briefly review the "classical" hydrodynamic form of the coupled evolution equations for the film height and surfactant concentration that are well established for small concentrations. Then we re-formulate the basic model as a gradient dynamics based on an underlying free energy functional that accounts for wettability and capillarity. Based on this re-formulation in the framework of nonequilibrium thermodynamics, we propose extensions of the basic hydrodynamic model that account for (i) nonlinear equations of state, (ii) surfactant-dependent wettability, (iii) surfactant phase transitions, and (iv) substrate-mediated condensation. In passing, we discuss important differences to most of the models found in the literature.

  5. Dewetting and deposition of thin films with insoluble surfactants from curved silicone hydrogel substrates.

    PubMed

    Bhamla, M Saad; Balemans, Caroline; Fuller, Gerald G

    2015-07-01

    We investigate the stabilizing effect of insoluble surfactant monolayers on thin aqueous films. We first describe an experimental platform that enables the formation of aqueous films laden with dipalmitoylphosphatidylcholine (DPPC) monolayers on curved silicone hydrogel (SiHy) substrates. We show that these surfactant layers extend the lifetime of the aqueous films. The films eventually "dewet" by the nucleation and growth of dry areas and the onset of this dewetting can be controlled by the surface rheology of the DPPC layer. We thus demonstrate that increasing the interfacial rheology of the DPPC layer leads to stable films that delay dewetting. We also show that dewetting can be exploited to controllably pattern the underlying curved SiHy substrates with DPPC layers.

  6. Coating of an inclined plane in the presence of insoluble surfactant.

    PubMed

    Edmonstone, B D; Matar, O K; Craster, R V

    2005-07-01

    We consider the flow of a thin liquid film coating an inclined plane in the presence of an insoluble surfactant. A fully non-linear two-dimensional system of governing equations is formulated using lubrication theory to describe the dynamics. Numerical simulations of this system highlight a fingering instability present at the main fluid front and elucidate the role of surfactant in the destabilizing mechanism. A full parametric study is undertaken which reveals the dependence of the fingering characteristics on system parameters. Numerical solutions at low angles of inclination are also obtained in order to illustrate the connection between gravitationally driven fingering and the instability induced by surfactant on a flat substrate. The similarities and differences between the destabilizing mechanisms in each case are discussed.

  7. Derivation of a continuum model and the energy law for moving contact lines with insoluble surfactants

    SciTech Connect

    Zhang, Zhen Xu, Shixin; Ren, Weiqing

    2014-06-15

    A continuous model is derived for the dynamics of two immiscible fluids with moving contact lines and insoluble surfactants based on thermodynamic principles. The continuum model consists of the Navier-Stokes equations for the dynamics of the two fluids and a convection-diffusion equation for the evolution of the surfactant on the fluid interface. The interface condition, the boundary condition for the slip velocity, and the condition for the dynamic contact angle are derived from the consideration of energy dissipations. Different types of energy dissipations, including the viscous dissipation, the dissipations on the solid wall and at the contact line, as well as the dissipation due to the diffusion of surfactant, are identified from the analysis. A finite element method is developed for the continuum model. Numerical experiments are performed to demonstrate the influence of surfactant on the contact line dynamics. The different types of energy dissipations are compared numerically.

  8. Generation of transverse waves in a liquid layer with insoluble surfactant subjected to temperature gradient

    NASA Astrophysics Data System (ADS)

    Mikishev, Alexander B.; Friedman, Barry A.; Nepomnyashchy, Alexander A.

    2016-12-01

    The formation of Faraday waves (FWs) at the surfactant-covered free surface of a vertically vibrated liquid layer is considered. The layer is subjected to a vertical temperature gradient. The surfactant is insoluble. Linear stability analysis and the Floquet method are used for disturbances with arbitrary wave numbers to find the regions of critical vibration amplitude where FWs are generated. The problem is considered for the semi-infinite liquid layer, as well as for the layer of a finite depth. It is shown numerically, that in the semi-infinite case the critical tongue of a neutral stability curve corresponding to the lowest value of the forcing amplitude is related to the subharmonic instability mode. It changes to the harmonic one in the case of finite depth. The influence of thermocapillary Marangoni number on the critical amplitude of FWs is studied. The growth of that number stabilizes the system, however, this effect is very weak.

  9. Laboratory Simulated Acid-Sulfate Weathering of Basaltic Materials: Implications for Formation of Sulfates at Meridiani Planum and Gusev Crater, Mars

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, Douglas W.; Morris, Richard V.; Mertzman, A.

    2006-01-01

    Acid-sulfate weathering of basaltic materials is a candidate formation process for the sulfate-rich outcrops and rocks at the MER rover Opportunity and Spirit landing sites. To determine the style of acid-sulfate weathering on Mars, we weathered basaltic materials (olivine-rich glassy basaltic sand and plagioclase feldspar-rich basaltic tephra) in the laboratory under different oxidative, acid-sulfate conditions and characterized the alteration products. We investigated alteration by (1) sulfuric-acid vapor (acid fog), (2) three-step hydrothermal leaching treatment approximating an open system and (3) single-step hydrothermal batch treatment approximating a "closed system." In acid fog experiments, Al, Fe, and Ca sulfates and amorphous silica formed from plagioclase-rich tephra, and Mg and Ca sulfates and amorphous silica formed from the olivine-rich sands. In three-step leaching experiments, only amorphous Si formed from the plagioclase-rich basaltic tephra, and jarosite, Mg and Ca sulfates and amorphous silica formed from olivine-rich basaltic sand. Amorphous silica formed under single-step experiments for both starting materials. Based upon our experiments, jarosite formation in Meridiani outcrop is potential evidence for an open system acid-sulfate weathering regime. Waters rich in sulfuric acid percolated through basaltic sediment, dissolving basaltic phases (e.g., olivine) and forming jarosite, other sulfates, and iron oxides. Aqueous alteration of outcrops and rocks on the West Spur of the Columbia Hills may have occurred when vapors rich in SO2 from volcanic sources reacted with basaltic materials. Soluble ions from the host rock (e.g., olivine) reacted with S to form Ca-, Mg-, and other sulfates along with iron oxides and oxyhydroxides.

  10. Allotropic control: How certain fluorinated carbonate electrolytes protect aluminum current collectors by promoting the formation of insoluble coordination polymers

    SciTech Connect

    Shkrob, Ilya A.; Pupek, Krzysztof Z.; Abraham, Daniel P.

    2016-07-28

    Here, there is a strong incentive for increasing the operation voltage of Li-ion cells above 4.5 V in order to increase the density of stored energy. Aluminum is an inexpensive, lightweight metal that is commonly used as a positive electrode current collector in these cells. Imide LiX salts, such as lithium bis(trifluoromethylsulfonyl)imide (X = TFSI), and lithium bis(fluorosulfonyl)imide (X = FSI), are chemically stable on the energized lithiated transition metal oxide electrodes, but their presence in the electrolyte causes rapid anodic dissolution and pitting of Al current collectors at potentials exceeding 4.0 V versus Li/Li+. For LiBF4 and LiPF6, the release of HF near the energized surfaces passivates the exposed Al metal, inhibiting this pitting corrosion, but it also causes the gradual degradation of the cathode active material, negating this important advantage. Here we report that in certain electrolytes containing fluorinated carbonate solvents and LiX salts, the threshold voltage for safe operation of Al current collectors can be increased to 5.5 V versus Li/Li+. Interestingly, the most efficient solvent also facilitates the formation of an insoluble gel when AlX3 is introduced into this solvent. We suggest that this solvent promotes the aggregation of coordination polymers of AlX3 at the exposed Al surface that isolate this surface from the electrolyte, thereby preventing further Al dissolution and corrosion. Other examples of Al collector protection may also involve this mechanism. Our study suggests that such “allotropic control” could be a way of widening the operation window of Li-ion cells without electrode deterioration, Al current collector corrosion, and electrolyte breakdown.

  11. Hot Melt Extrusion: Development of an Amorphous Solid Dispersion for an Insoluble Drug from Mini-scale to Clinical Scale.

    PubMed

    Agrawal, Anjali M; Dudhedia, Mayur S; Zimny, Ewa

    2016-02-01

    The objective of the study was to develop an amorphous solid dispersion (ASD) for an insoluble compound X by hot melt extrusion (HME) process. The focus was to identify material-sparing approaches to develop bioavailable and stable ASD including scale up of HME process using minimal drug. Mixtures of compound X and polymers with and without surfactants or pH modifiers were evaluated by hot stage microscopy (HSM), polarized light microscopy (PLM), and modulated differential scanning calorimetry (mDSC), which enabled systematic selection of ASD components. Formulation blends of compound X with PVP K12 and PVP VA64 polymers were extruded through a 9-mm twin screw mini-extruder. Physical characterization of extrudates by PLM, XRPD, and mDSC indicated formation of single-phase ASD's. Accelerated stability testing was performed that allowed rapid selection of stable ASD's and suitable packaging configurations. Dissolution testing by a discriminating two-step non-sink dissolution method showed 70-80% drug release from prototype ASD's, which was around twofold higher compared to crystalline tablet formulations. The in vivo pharmacokinetic study in dogs showed that bioavailability from ASD of compound X with PVP VA64 was four times higher compared to crystalline tablet formulations. The HME process was scaled up from lab scale to clinical scale using volumetric scale up approach and scale-independent-specific energy parameter. The present study demonstrated systematic development of ASD dosage form and scale up of HME process to clinical scale using minimal drug (∼500 g), which allowed successful clinical batch manufacture of enabled formulation within 7 months.

  12. Allotropic control: How certain fluorinated carbonate electrolytes protect aluminum current collectors by promoting the formation of insoluble coordination polymers

    DOE PAGES

    Shkrob, Ilya A.; Pupek, Krzysztof Z.; Abraham, Daniel P.

    2016-07-28

    Here, there is a strong incentive for increasing the operation voltage of Li-ion cells above 4.5 V in order to increase the density of stored energy. Aluminum is an inexpensive, lightweight metal that is commonly used as a positive electrode current collector in these cells. Imide LiX salts, such as lithium bis(trifluoromethylsulfonyl)imide (X = TFSI), and lithium bis(fluorosulfonyl)imide (X = FSI), are chemically stable on the energized lithiated transition metal oxide electrodes, but their presence in the electrolyte causes rapid anodic dissolution and pitting of Al current collectors at potentials exceeding 4.0 V versus Li/Li+. For LiBF4 and LiPF6, themore » release of HF near the energized surfaces passivates the exposed Al metal, inhibiting this pitting corrosion, but it also causes the gradual degradation of the cathode active material, negating this important advantage. Here we report that in certain electrolytes containing fluorinated carbonate solvents and LiX salts, the threshold voltage for safe operation of Al current collectors can be increased to 5.5 V versus Li/Li+. Interestingly, the most efficient solvent also facilitates the formation of an insoluble gel when AlX3 is introduced into this solvent. We suggest that this solvent promotes the aggregation of coordination polymers of AlX3 at the exposed Al surface that isolate this surface from the electrolyte, thereby preventing further Al dissolution and corrosion. Other examples of Al collector protection may also involve this mechanism. Our study suggests that such “allotropic control” could be a way of widening the operation window of Li-ion cells without electrode deterioration, Al current collector corrosion, and electrolyte breakdown.« less

  13. Steam injection well gravel pack material of sintered bauxite

    SciTech Connect

    Elson, T. D.; Millhone, R. S.

    1985-08-27

    A packing material useful in a gravel pack for open or cased wells or in a prepack for use in steam or hot fluid injection and production wells. The packing material is a material which is insoluble in high temperature caustic fluids and subsurface formation fluids. Sintered bauxite is a claimed material.

  14. Steam injection well gravel prepack material of sintered bauxite

    SciTech Connect

    Elson, T. D.; Millhone, R. S.

    1985-10-22

    A packing material useful in a gravel pack for open or cased wells or in a prepack for use in steam or hot fluid injection and production wells. The packing material is a material which is insoluble in high temperature caustic fluids and subsurface formation fluids. Sintered bauxite is a claimed material.

  15. Difructose anhydride III enhances bioavailability of water-insoluble iron in anemic Vietnamese women.

    PubMed

    Nakamori, Masayo; Hien, Vu Thi Thu; Khan, Nguyen Cong; Lam, Nguyen Thi; Dung, Nguyen Tri; Uotsu, Nobuo; Shiomi, Takuya; Okuhara, Yasuhide; Kise, Mitsuo; Shigematsu, Norihiro; Yamamoto, Shigeru

    2010-01-01

    Difructose anhydride III (DFAIII) is an indigestible disaccharide and has been shown to enhance iron absorption in animal studies; however, the effect has not been investigated in anemic subjects. We investigated the efficacy of co-administration of DFAIII with water-insoluble iron in the treatment of iron deficiency anemia in Vietnamese women. One hundred sixty-eight moderately anemic women (80 g/Linsoluble iron in anemic Vietnamese women.

  16. Insoluble Off-Pathway Aggregates as Crowding Agents during Amyloid Fibril Formation.

    PubMed

    Crespo, Rosa; Villar-Alvarez, Eva; Taboada, Pablo; Rocha, Fernando A; Damas, Ana M; Martins, Pedro M

    2017-03-08

    The study of drug candidates for the treatment of amyloidosis and neurodegenerative diseases frequently involves in vitro measurements of amyloid fibril formation. Macromolecular crowding and off-pathway aggregation (OPA) are, by different reasons, two important phenomena affecting the scalability of amyloid inhibitors and their successful application in vivo. On the one hand, the cellular milieu is crowded with macromolecules that drastically increase the effective (thermodynamic) concentration of the amyloidogenic protein. On the other hand, off-pathway aggregates, rather than amyloid fibrils, are increasingly appointed as causative agents of toxicity. The present contribution reveals that insoluble off-pathway aggregates of hen egg-white lysozyme (HEWL) are a peculiar type of crowding agents that, unlike classical macromolecular crowders, decrease the thermodynamic concentration of protein. Illustrating this effect, OPA is shown to resume after lowering the fraction of insoluble aggregates at a constant soluble HEWL concentration. Protein depletion and thioflavin-T fluorescence progress curves indicate that OPA rebirth is not accompanied by additional amyloid fibril formation. The crystallization-like model extended to account for OPA and time-dependent activity coefficients is able to fit multiple kinetic results using a single set of three parameters describing amyloid nucleation, autocatalytic growth, and off-pathway nucleation. The list of fitted results notably includes the cases of aggregation rebirth and all types of progress curves measured for different HEWL concentrations. The quantitative challenges posed by macromolecular crowding and OPA find here a unified response with broader implications for the development of on- and off-pathway inhibitors.

  17. Spatial distribution and potential sources of trace metals in insoluble particles of snow from Urumqi, China.

    PubMed

    Li, Xiaolan; Jiang, Fengqing; Wang, Shaoping; Turdi, Muyesser; Zhang, Zhaoyong

    2015-01-01

    The purpose of this work is to characterize trace elements in snow in urban-suburb gradient over Urumqi city, China. The spatial distribution patterns of 11 trace metals in insoluble particulate matters of snow were revealed by using 102 snow samples collected in and around urban areas of Urumqi, a city suffering from severe wintertime air pollution in China. Similar spatial distribution for Mn, Cu, Zn, Ni, and Pb was found and their two significant high-value areas located in the west and east, respectively, and a high-value area in the south, which were correlated with factory emissions, traffic activities, and construction fugitive dust. The high-value areas of Cr, Ni, and V occurred in the northeast corner and along main traffic paths, which were linked to oil refinery and vehicular emissions. High value of Be presented in the west of the city. The high-value area of Co in the northeast could be related to local soil. Cd and U displayed relatively even spatial patterns in the urban area. In view of distance from the urban center, e.g., from the first circular belt to the fourth circular belt, except Be, V, Cd, and U, the contents of other metals generally decreased from the first circular belt to the forth circular belt, implying the effect of human activity clearly. Additionally, prevailing northwesterly winds and occasionally southeasterly winds in winter were associated with decreased, generally, concentrations of trace metal in snow from the urban center to the southern suburb along a northwest and southeast transect. The information on concentrations and spatial distributions of these metals in insoluble particles of snow in winter will be valuable for further environmental protection and planning.

  18. Use of anionic denaturing detergents to purify insoluble proteins after overexpression

    PubMed Central

    2012-01-01

    Background Many proteins form insoluble protein aggregates, called “inclusion bodies”, when overexpressed in E. coli. This is the biggest obstacle in biotechnology. Ever since the reversible denaturation of proteins by chaotropic agents such as urea or guanidinium hydrochloride had been shown, these compounds were predominantly used to dissolve inclusion bodies. Other denaturants exist but have received much less attention in protein purification. While the anionic, denaturing detergent sodiumdodecylsulphate (SDS) is used extensively in analytical SDS-PAGE, it has rarely been used in preparative purification. Results Here we present a simple and versatile method to purify insoluble, hexahistidine-tagged proteins under denaturing conditions. It is based on dissolution of overexpressing bacterial cells in a buffer containing sodiumdodecylsulfate (SDS) and whole-lysate denaturation of proteins. The excess of detergent is removed by cooling and centrifugation prior to affinity purification. Host- and overexpressed proteins do not co-precipitate with SDS and the residual concentration of detergent is compatible with affinity purification on Ni/NTA resin. We show that SDS can be replaced with another ionic detergent, Sarkosyl, during purification. Key advantages over denaturing purification in urea or guanidinium are speed, ease of use, low cost of denaturant and the compatibility of buffers with automated FPLC. Conclusion Ionic, denaturing detergents are useful in breaking the solubility barrier, a major obstacle in biotechnology. The method we present yields detergent-denatured protein. Methods to refold proteins from a detergent denatured state are known and therefore we propose that the procedure presented herein will be of general application in biotechnology. PMID:23231964

  19. A simple procedure for preparing chitin oligomers through acetone precipitation after hydrolysis in concentrated hydrochloric acid.

    PubMed

    Kazami, Nao; Sakaguchi, Masayoshi; Mizutani, Daisuke; Masuda, Tatsuhiko; Wakita, Satoshi; Oyama, Fumitaka; Kawakita, Masao; Sugahara, Yasusato

    2015-11-05

    Chitin oligomers are of interest because of their numerous biologically relevant properties. To prepare chitin oligomers containing 4-6 GlcNAc units [(GlcNAc)4-6], α- and β-chitin were hydrolyzed with concentrated hydrochloric acid at 40 °C. The reactant was mixed with acetone to recover the acetone-insoluble material, and (GlcNAc)4-6 was efficiently recovered after subsequent water extraction. Composition analysis using gel permeation chromatography and MALDI-TOF mass spectrometry indicated that (GlcNAc)4-6 could be isolated from the acetone-insoluble material with recoveries of approximately 17% and 21% from the starting α-chitin and β-chitin, respectively. The acetone precipitation method is highly useful for recovering chitin oligomers from the acid hydrolysate of chitin. The changes in the molecular size and higher-order structure of chitin during the course of hydrolysis were also analyzed, and a model that explains the process of oligomer accumulation is proposed.

  20. Research on the interaction of hydrogen-bond acidic polymer sensitive sensor materials with chemical warfare agents simulants by inverse gas chromatography.

    PubMed

    Yang, Liu; Han, Qiang; Cao, Shuya; Huang, Feng; Qin, Molin; Guo, Chenghai; Ding, Mingyu

    2015-06-02

    Hydrogen-bond acidic polymers are important high affinity materials sensitive to organophosphates in the chemical warfare agent sensor detection process. Interactions between the sensor sensitive materials and chemical warfare agent simulants were studied by inverse gas chromatography. Hydrogen bonded acidic polymers, i.e., BSP3, were prepared for micro-packed columns to examine the interaction. DMMP (a nerve gas simulant) and 2-CEES (a blister agent simulant) were used as probes. Chemical and physical parameters such as heats of absorption and Henry constants of the polymers to DMMP and 2-CEES were determined by inverse gas chromatography. Details concerning absorption performance are also discussed in this paper.

  1. Fabrication and electrochemical properties of insoluble fullerene-diamine adduct thin-films as buffer layer by alternate immersion process

    NASA Astrophysics Data System (ADS)

    Saito, Jo; Akiyama, Tsuyoshi; Suzuki, Atsushi; Oku, Takeo

    2017-01-01

    Insoluble fullerene-diamine adduct thin-films consisting of C60 and 1,2-diaminoethane were easily fabricated on an electrode by an alternate immersion process. Formation of the C60-diamine adduct films were confirmed using transmission absorption spectroscopy and atomic force microscopy. An inverted-type organic solar cells were fabricated by using the C60-diamine adduct film as the electron transport layer. The resultant photoelectric conversation performance of the solar cells suggested that photocurrent is generated via the photoexcitation of polythiophene. The result suggests that the present insoluble fullerene-diamine adduct films worked as buffer layer for organic thin-film solar cells.

  2. Thermal behavior of potato starch and water-vaporization behavior of its paste controlled with amino acid and peptide-rich food materials.

    PubMed

    Sakauchi, Satoshi; Hattori, Makoto; Yoshida, Tadashi; Yagishita, Takahiro; Ito, Koichi; Akemitsu, Shin-Ichi; Takahashi, Koji

    2010-03-01

    The particular effect of 4 kinds of amino acid and peptide-rich food material (APRM) containing different charged amino acid contents on the gelatinization and retrogradation behavior of potato starch granules and on the water-vaporization behavior was analyzed by differential scanning calorimetry, rapid viscoanalysis, x-ray diffractometry, thermal gravimetry-differential thermal analysis, and pulsed NMR. APRM with a high-charged amino acid content produced unique gelatinization and retrogradation behavior in terms of an elevated gelatinization temperature, reduced viscosity, higher setback, and lower retrograded starch melting enthalpy. The recovered x-ray diffraction intensity decreased with increasing charged amino acid content. APRM with high-charged amino acid content could provide an improved paste having easy vaporization of external water in the swollen starch granules due to the reduced swelling.

  3. In vitro hypoglycemic effects of different insoluble fiber-rich fractions prepared from the peel of Citrus sinensis L. cv. Liucheng.

    PubMed

    Chau, Chi-Fai; Huang, Ya-Ling; Lee, Mao-Hsiang

    2003-10-22

    Insoluble fiber-rich fractions (FRFs), including insoluble dietary fiber, alcohol-insoluble solid, and water-insoluble solid, were isolated from the peel of Citrus sinensis L. cv. Liucheng. We found that these three FRFs could effectively adsorb glucose, retard glucose diffusion, and inhibit the activity of alpha-amylase to different extents. These mechanisms might create a concerted benefit in decreasing the rate of glucose absorption and eventually lower the concentration of postprandial serum glucose. The potential hypoglycemic effects of these FRFs suggested that they could be incorporated as low-calorie bulk ingredients in high-fiber foods to reduce calorie level and control blood glucose level.

  4. Fiber opticpH sensor for the acidic range using fluorescent dye-doped sol-gel materials

    NASA Astrophysics Data System (ADS)

    Manyam, Upendra H.

    A plethora of new sensor technologies have emerged for chemical, biological, environmental and security applications. However, their adoption has been constrained by lack of integration of vastly different technical areas. Fiber optic chemical sensing is one such technology; a combination of spectroscopy, materials science and optical engineering. In this work, the example of an acidic pH sensor is used to individually develop these three areas and integrate them into a working device. Acidic pH is an important parameter in chemical processes, with no suitable optical alternatives. The fluorescent pH indicator 5-(and 6)-carboxydichlorofluorescein (CDCF) was doped in a sol-gel matrix. CDCF has a pKa of 4.53, making it well suited for the acidic range. MTMS and TEOS gels were developed as films with good mechanical and chemical stability. The pH state of the immobilized dye affects the ratio of the absorption peaks. The fluorescence spectrum was red shifted in the organically modified gel. The fluorescence of hybrid spin-coated thin films resembled that of TEOS gels rather than that of hybrid bulk gels. The pH response was reversible and repeatable with a dynamic range of 5 pH units. Changes in ionic strength cause hysteresis in the sensor's response, which disappears when the film surface is saturated with electrolytes. The mechanical strength of the films in air and when immersed in solution was improved by using specific aging routines. Photo-bleaching was reduced by limiting excitation time to the duration of the measurement. Sonication, organic modification and aging in pH 2 buffer reduced leaching of the dye. Solid surface energy of the gels increased with organic modification. Hybrid gels were hydrophobic, resulting in slow response times. The diffusion constant of hydronium ions was found to depend on protonation state of the indicator and ionic strength of the solution. The diffusion constant in 0%MTMS and 10%MTMS films was of the order of 10-9 cm2/s, while

  5. Structural, optical, thermal and mechanical characterization of an organic nonlinear optical material: 4-methyl-3-nitrobenzoic acid single crystal

    NASA Astrophysics Data System (ADS)

    Bharathi, M. Divya; Ahila, G.; Mohana, J.; Chakkaravarthi, G.; Anbalagan, G.

    2016-11-01

    Organic single crystals of 4-methyl-3-nitrobenzoic acid (4M3N) have been grown by slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction study reveals that 4M3N crystallizes in monoclinic system with space group P21/n. The crystalline perfection of the crystal was analyzed by high resolution X-ray diffraction (HRXRD) measurements. The functional groups present in 4M3N have been identified from FT-IR and FT-Raman spectra. The lower cut-off wavelength of 4M3N is found to be 404 nm and the optical band gap is calculated as 2.91 eV. The refractive index shows normal behavior with wavelength. The physio chemical changes, decomposition and stability of the 4M3N compound were established by TG-DTA studies. Vickers microhardness measurement concludes that 4M3N belongs to soft material (n=2.5) category. The LDT value is found to be higher than that of KDP and some of the important organic NLO materials. The third order nonlinear refractive index and nonlinear absorption coefficient of the 4M3N have been measured by Z-scan studies. The imaginary and real parts of the third-order susceptibility values were determined as Im χ3=9.129×10-11 esu and Re χ3=1.4034×10-9 esu respectively. The dislocation density was calculated to be 3.0448×106 cm-2 which indicates the quality of the crystal.

  6. Effect of chemical composition on corneal tissue response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid.

    PubMed

    Lai, Jui-Yang

    2014-01-01

    The purpose of this work was to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and hydrogel material compatibility towards ocular anterior segment tissues, particularly the corneal endothelium. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Then, the 7-mm-diameter membrane implants made from photopolymerized materials were placed into the ocular anterior chamber for 4days and assessed by biomicroscopic examinations, corneal thickness measurements, and quantitative real-time reverse transcription polymerase chain reaction analyses. The poly(HEMA-co-AAc) implants prepared from the solution mixture containing 0-10vol.% AAc displayed good biocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the enhanced inflammatory response, decreased endothelial cell density, and increased ocular score and corneal thickness were observed, probably due to the influence of surface charge of copolymer membranes. On the other hand, the ionic pump function of corneal endothelium exposed to photopolymerized membranes was examined by analyzing the Na(+),K(+)-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of the implants having higher amount of AAc incorporated in the copolymers (i.e., 15.1 to 24.7μmol) and zeta potential (i.e., -38.6 to -56.5mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal tissue responses to polymeric biomaterials.

  7. Effects of simple acid leaching of crushed and powdered geological materials on high-precision Pb isotope analyses

    NASA Astrophysics Data System (ADS)

    Todd, Erin; Stracke, Andreas; Scherer, Erik E.

    2015-07-01

    We present new results of simple acid leaching experiments on the Pb isotope composition of USGS standard reference material powders and on ocean island basalt whole rock splits and powders. Rock samples were leached with cold 6 N HCl in an ultrasonic bath, then on a hot plate, and washed with ultrapure H2O before sample digestion in HF-HNO3 and chromatographic purification of Pb. Lead isotope analyses were measured by Tl-doped MC-ICPMS. Intrasession and intersession analytical reproducibilities of repeated analyses of both synthetic Pb solutions and Pb from single digests of chemically processed natural samples were generally better than 100 ppm (2 SD). The comparison of leached and unleached samples shows that leaching consistently removes variable amounts of contaminants that differ in Pb isotopic composition for different starting materials. For repeated digests of a single sample, analyses of leached samples reproduce better than those of unleached ones, confirming that leaching effectively removes most of the heterogeneously distributed extraneous Pb. Nevertheless, the external reproducibility of leached samples is still up to an order of magnitude worse than that of Pb solution standards (˜100 ppm). More complex leaching methods employed by earlier studies yield Pb isotope ratios within error of those produced by our method and at similar levels of reproducibility, demonstrating that our simple leaching method is as effective as more complex leaching techniques. Therefore, any Pb isotope heterogeneity among multiple leached digests of samples in excess of the external reproducibility is attributed to inherent isotopic heterogeneity of the sample. The external precision of ˜100 ppm (2 SD) achieved for Pb isotope ratio determination by Tl-doped MC-ICPMS is thus sufficient for most rocks. The full advantage of the most precise Pb isotope analytical methods is only realized in cases where the natural isotopic heterogeneity among samples in a studied suite is

  8. Recovery of valuable metals from waste cathode materials of spent lithium-ion batteries using mild phosphoric acid.

    PubMed

    Chen, Xiangping; Ma, Hongrui; Luo, Chuanbao; Zhou, Tao

    2017-03-15

    Sustainable recycling of valuable metals from spent lithium-ion batteries (LIBs) may be necessary to alleviate the depletion of strategic metal resources and potential risk of environmental pollution. Herein a hydrometallurgical process was proposed to explore the possibility for the recovery of valuable metals from the cathode materials (LiCoO2) of spent LIBs using phosphoric acid as both leaching and precipitating agent under mild leaching conditions. According to the leaching results, over 99% Co can be separated and recovered as Co3(PO4)2 in a short-cut process involved merely with leaching and filtrating, under the optimized leaching conditions of 40°C (T), 60min (t), 4 vol.% H2O2, 20mLg(-1) (L/S) and 0.7mol/L H3PO4. Then leaching kinetics was investigated based on the logarithmic rate kinetics model and the obtained results indicate that the leaching of Co and Li fits well with this model and the activation energies (Ea) for Co and Li are 7.3 and 10.2kJ/mol, respectively. Finally, it can be discovered from characterization results that the obtained product is 97.1% pure cobalt phosphate (Co3(PO4)2).

  9. Hazardous waste to materials: recovery of molybdenum and vanadium from acidic leach liquor of spent hydroprocessing catalyst using alamine 308.

    PubMed

    Sahu, K K; Agrawal, Archana; Mishra, D

    2013-08-15

    Recovery of valuable materials/metals from waste goes hand in hand with environmental protection. This paper deals with the development of a process for the recovery of metals such as Mo, V, Ni, Al from spent hydroprocessing catalyst which may otherwise cause a nuisance if dumped untreated. A detailed study on the separation of molybdenum and vanadium from the leach solution of spent hydroprocessing catalyst of composition: 27.15% MoO₃, 1.7% V₂O₅, 3.75% NiO, 54.3% Al₂O₃, 2.3% SiO₂ and 10.4% LOI is reported in this paper. The catalyst was subjected to roasting under oxidizing atmosphere at a temperature of about 550 °C and leaching in dilute sulphuric acid to dissolve molybdenum, vanadium, nickel and part of aluminium. Metals from the leach solution were separated by solvent extraction. Both molybdenum and vanadium were selectively extracted with a suitable organic solvent leaving nickel and dissolved aluminium in the raffinate. Various parameters such as initial pH of the aqueous feed, organic to aqueous ratio (O:A), solvent concentration etc. were optimized for the complete extraction and recovery of Mo and V. Molybdenum and vanadium from the loaded organic were stripped by ammonia solution. They were recovered as their corresponding ammonium salt by selective precipitation, and were further calcined to get the corresponding oxides in pure form.

  10. Effects of crystalline structures and surface functional groups on the adsorption of haloacetic acids by inorganic materials.

    PubMed

    Punyapalakul, Patiparn; Soonglerdsongpha, Suwat; Kanlayaprasit, Chutima; Ngamcharussrivichai, Chawalit; Khaodhiar, Sutha

    2009-11-15

    The effects of the crystalline structure and surface functional groups of porous inorganic materials on the adsorption of dichloroacetic acid (DCAA) were evaluated by using hexagonal mesoporous silicates (HMS), two surface functional group (3-aminopropyltriethoxy- and 3-mercaptopropyl-) modified HMSs, faujasite Y zeolite and activated alumina as adsorbents, and compared with powdered activated carbon (PAC). Selective adsorption of HAA(5) group was studied by comparing single and multiple-solute solution, including effect of common electrolytes in tap water. Adsorption capacities were significantly affected by the crystalline structure. Hydrogen bonding is suggested to be the most important attractive force. Decreasing the pH lower than the pH(zpc) increased the DCAA adsorption capacities of these adsorbents due to electrostatic interaction and hydrogen bonding caused by protonation of the hydronium ion. Adsorption capacities of HAA(5) on HMS did not relate to molecular structure of HAA(5). Common electrolytes did not affect the adsorption capacities and selectivity of HMS for HAA5, while they affected those of PAC.

  11. Ampholine-functionalized hybrid organic-inorganic silica material as sorbent for solid-phase extraction of acidic and basic compounds.

    PubMed

    Wang, Tingting; Chen, Yihui; Ma, Junfeng; Chen, Mingliang; Nie, Chenggang; Hu, Minjie; Li, Ying; Jia, Zhijian; Fang, Jianghua; Gao, Haoqi

    2013-09-20

    A novel sorbent for solid-phase extraction (SPE) was synthesized by chemical immobilization of ampholine on hybrid organic-inorganic silica material. The ampholine-functionalized hybrid organic-inorganic silica sorbent is consisted of aliphatic amine groups, carboxyl groups and long carbon chains, allowing for extraction of both acidic and basic compounds. The retention properties of the developed sorbent were evaluated for 1-hydroxy-2-naphthoic acid (HNA), 1-naphthoic acid (NA), 3-hydroxybenzoic acid (HBA), benzoic acid (BA), sorbic acid (SA), vanillic aldehyde (VA), butyl 4-hydroxybenzoate (BHB), propyl 4-hydroxybenzoate (PHB), ethyl 4-hydroxybenzoate (EHB), and methyl 4-hydroxybenzoate (MHB). The results show that such a sorbent has three types of interaction, i.e., electrostatic interaction, hydrophobic interaction, and hydrogen bonding, exhibiting high extraction efficiency towards the compounds tested. The adsorption capacities of the analytes ranged from 0.61 to 6.54μgmg(-1). The reproducibility of the sorbent preparation was evaluated at three spiking concentration levels, with relative standard deviations (RSDs) of 1.0-10.5%. The recoveries of ten acidic and basic compounds spiked in beverage Coca-Cola(®) sample ranged from 82.5% to 98.2% with RSDs less than 5.8%. Under optimum conditions, the ampholine-functionalized hybrid organic-inorganic silica sorbent rendered higher extraction efficiency for acidic compounds than that of the commercially available ampholine-functionalized silica particles, and was comparable to that of the commercial Oasis WAX and Oasis WCX.

  12. Novel lead-graphene and lead-graphite metallic composite materials for possible applications as positive electrode grid in lead-acid battery

    NASA Astrophysics Data System (ADS)

    Yolshina, L. A.; Yolshina, V. A.; Yolshin, A. N.; Plaksin, S. V.

    2015-03-01

    Novel lead-graphene and lead-graphite metallic composites which melt at temperature of the melting point of lead were investigated as possible positive current collectors for lead acid batteries in sulfuric acid solution. Scanning electron microscopy, Raman spectroscopy, difference scanning calorimetry, cyclic voltammetry and prolonged corrosion tests were employed to characterize the effect of the newly proposed lead-carbon metallic composites on the structure and electrochemical properties of positive grid material. Both lead-graphene and lead-graphite metallic composite materials show the similar electrochemical characteristics to metallic lead in the voltage range where the positive electrodes of lead acid batteries operate. It has been shown that carbon both as graphene and graphite does not participate in the electrochemical process but improve corrosion and electrochemical characteristics of both metallic composite materials. No products of interaction of lead with sulfuric acid were formed on the surface of graphene and graphite so as it was not found additional peaks of carbon discharge on voltammograms which could be attributed to the carbon. Graphene inclusions in lead prevent formation of leady oxide nanocrystals which deteriorate discharge characteristics of positive electrode of LAB. Both lead-graphene alloy and lead-graphite metallic composite proved excellent electrochemical and corrosion behavior and can be used as positive grids in lead acid batteries of new generation.

  13. Comparative Study of Stearic Acid/Iron-Oxide Binary and Stearic Acid/Iron-Oxide/Titanium-Oxide Ternary for Use as Energy Storage Material

    NASA Astrophysics Data System (ADS)

    Andiarto, Rizky; Khalish Nuryadin, Muhammad; Saleh, Rosari

    2016-04-01

    In this work, a series of stearic acid/Fe3O4, and stearic acid/Fe3O4/TiO2 nanocomposites for thermal energy storage (TES) system were synthesized through a two-step process. Fe3O4 nanoparticles and Fe3O4/TiO2 nanocomposites were first prepared using sol-gel methods and then both samples were mixed into stearic acid by dispersion technique at three different weight % ratio to stearic acid: 5%, 10% and 15% to obtain stearic acid/Fe3O4, and stearic acid/Fe3O4/TiO2 nanocomposites. Morphologies and structural properties of the samples were characterized by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectroscopy (EDX), while thermal properties of the sample were determined by differential scanning calorimetry (DSC) and fhermogravimetric analysis (TGA). The XRD patterns demonstrate, that stearic acid/Fe3O4 contained characteristic peaks of Fe3O4 and stearic acid structures, while peaks corresponded to anatase TiO2 structures appear in stearic acid/ Fe3O4/TiO2 nanocomposites. From the DSC measurements, it is found that the maximum latent heat was found at samples with weight ratio of 5%. Moreover, the enhancement up to 20% of latent heat in solidifying as well as melting processes was observed. TGA measurements show high degradation temperature in the range of 246 - 251°C. The TGA results also shows that the residual mass of the sample matches the composition of Fe3O4 and Fe3O4/TiO2 which is added to the stearic acid.

  14. An N-ethylated barbituric acid end-capped bithiophene as an electron-acceptor material in fullerene-free organic photovoltaics.

    PubMed

    Sullivan, Paul; Collis, Gavin E; Rochford, Luke A; Arantes, Junior Ferreira; Kemppinen, Peter; Jones, Tim S; Winzenberg, Kevin N

    2015-04-11

    A new evaporable electron acceptor material for organic photovoltaics based on N-ethyl barbituric acid bithiophene (EBB) has been demonstrated. Bilayer devices fabricated with this non-fullerene acceptor and boron subphthalocyanine chloride (SubPc) donor produce power conversion efficiencies as high as 2.6% with an extremely large open-circuit voltage approaching 1.4 V.

  15. Re-examining the applications of amylase in the sugar industry: Conquering the control of insoluble and soluble starch

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The new knowledge that there is markedly more insoluble starch than previously considered in products across both the sugarcane factory and refinery has processing implications. Processing parameters such as viscosity and filtration are implicated, as well as the application of '-amylases in the fa...

  16. Hydroxyl radical production by a heterogeneous Fenton reaction supported in insoluble tannin from bark of Pinus radiata.

    PubMed

    Romero, Romina; Contreras, David; Segura, Cristina; Schwederski, Brigitte; Kaim, Wolfgang

    2016-09-02

    Fenton reactions driven by dihydroxybenzenes (DHBs) have been used for pollutant removal via advanced oxidation processes (AOPs), but such systems have the disadvantage of DHB release into the aqueous phase. In this work, insoluble tannins from bark can be used to drive Fenton reactions and as a heterogeneous support. This avoids the release of DHBs into the aqueous phase and can be used for AOPs. The production of ·OH was investigated using a spin-trapping electron paramagnetic resonance technique (5-dimethyl-1-pyrroline-N-oxide/·OH) in the first minute of the reaction and a high-performance liquid chromatography-fluorescence technique (coumarin/7-hydroxycoumarin) for 20 min. The ·OH yield achieved using insoluble tannins from Pinus radiata bark was higher than that achieved using catechin to drive the Fenton reaction. The Fenton-like system driven by insoluble tannins achieved 92.6 ± 0.3 % degradation of atrazine in 30 min. The degradation kinetics of atrazine was linearly correlated with ·OH production. The increased reactivity in ·OH production and insolubility of the ligand are promising for the development of a new technique for degradation of pollutants in wastewater using heterogeneous Fenton systems.

  17. [Chemical characteristics and insoluble particulates' surface morphology of a snowfall process in the southeastern suburb of Urumqi].

    PubMed

    Lu, Hui; Wei, Wen-Shou; Cui, Cai-Xia; He, Qing; Wang, Yao

    2014-04-01

    In order to understand the composition and potential pollution of metal elements in precipitation in the southeastern suburb of Urumqi on February 21 to 23, 2012, soluble elements were determined by inductively coupled plasma mass spectrometry (ICP-MS); in addition, energy spectrum and morphological analysis were made for insoluble particulates. The results showed that the content of toxic heavy metals in snowfall was a little high; and the enrichment factors of Se, As and Cd were 124.65, 57.69 and 36.70, respectively, showing a typical coal pollution characteristic. The back trajectory cluster analysis suggested that the coal fly ash of snowfall mainly induced by air masses originated from the coal-fire power plant in the Southwestern sampling site. Morphology analyses conducted under an scan electron microscope demonstrated fly ash coming from coal burning process and irregular mineral are in the majority of insoluble particulates in snowfall, soot aggregates were compact, when the soot was wetted (the hygroscopic behaviour), and the morphology changed further. Insoluble particulates of the southeastern suburb of Urumqi were coal fly ash and insoluble soil minerals.

  18. Development of an analytical method to measure insoluble and soluble starch in sugarcane and sweet sorghum products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rapid, quantitative research method using microwave-assisted probe ultrasonication was developed to facilitate the determination of total insoluble, and soluble starch in various sugar crop products. Several variables that affect starch solubilization were evaluated, 1) conductive boiling time, 2...

  19. Conversion of olive tree biomass into fermentable sugars by dilute acid pretreatment and enzymatic saccharification.

    PubMed

    Cara, Cristóbal; Ruiz, Encarnación; Oliva, José Miguel; Sáez, Felicia; Castro, Eulogio

    2008-04-01

    The production of fermentable sugars from olive tree biomass was studied by dilute acid pretreatment and further saccharification of the pretreated solid residues. Pretreatment was performed at 0.2%, 0.6%, 1.0% and 1.4% (w/w) sulphuric acid concentrations while temperature was in the range 170-210 degrees C. Attention is paid to sugar recovery both in the liquid fraction issued from pretreatment (prehydrolysate) and that in the water-insoluble solid (WIS). As a maximum, 83% of hemicellulosic sugars in the raw material were recovered in the prehydrolysate obtained at 170 degrees C, 1% sulphuric acid concentration, but the enzyme accessibility of the corresponding pretreated solid was not very high. In turn, the maximum enzymatic hydrolysis yield (76.5%) was attained from a pretreated solid (at 210 degrees C, 1.4% acid concentration) in which cellulose solubilization was detected; moreover, sugar recovery in the prehydrolysate was the poorest one among all the experiments performed. To take account of fermentable sugars generated by pretreatment and the glucose released by enzymatic hydrolysis, an overall sugar yield was calculated. The maximum value (36.3 g sugar/100 g raw material) was obtained when pretreating olive tree biomass at 180 degrees C and 1% sulphuric acid concentration, representing 75% of all sugars in the raw material. Dilute acid pretreatment improves results compared to water pretreatment.

  20. Effect of addition of antibiotics and an antioxidant on the stability of tissue reference materials for domoic acid, the amnesic shellfish poison.

    PubMed

    McCarron, Pearse; Burrell, Stephen; Hess, Philipp

    2007-04-01

    Five separate reference materials (RMs) were prepared from a mussel (Mytilus edulis) tissue containing domoic acid (DA) from scallop hepatopancreas (Pecten maximus). Homogenates were separately spiked with antibiotics, an antioxidant, or a combination of both. Control materials did not contain any additives and were prepared from lightly cooked and autoclaved mussel tissues. Stability studies were run over a 148-day period at three different temperature conditions: -20 degrees C, +4 degrees C and +40 degrees C. DA contents in all materials were characterised by HPLC-UV. Homogeneities were demonstrated at the beginning of the study, with coefficients of variance of less than 4% (n = 9). DA was stable at -20 degrees C in all materials. The control materials showed significant degradation after two days at +40 degrees C, and after eight days at +4 degrees C. Each of the materials containing additives demonstrated better stability during the initial period of the study. In addition there was no significant degradation in any of the materials with additives stored at +4 degrees C over the duration of the study. The material containing a combination of the antibiotics and the antioxidant displayed the best stability of all the materials. There was no significant reduction in DA concentration at all temperature conditions after eight days, and after 32 days the decrease at +40 degrees C was still <20 %. Following this, a DA laboratory reference material (LRM) was prepared and, based on previous results, spiked with both the antioxidant and antibiotics. A short-term stability study on this material gave similar results to the corresponding material in the additives study. This study shows that combined use of the additives investigated in the preparation of a mussel tissue reference material for DA ensures analyte stability for a period of up to eight days at temperatures of up to +40 degrees C, a condition that is particularly important when shipping test materials