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1

Development and evaluation of sustained release tablet of betahistine hydrochloride using ion exchange resin tulsion t344.  

PubMed

An attempt was made to sustain the release of Betahistine hydrochloride by complexation technique using strong cation-exchange resin, Tulsion T344. The drug loading onto ion-exchange resin was optimized for mixing time, activation, effect of pH, swelling time, ratio of drug?:?resin, and temperature. The resinate was evaluated for micromeritic properties and characterized using XRPD and IR. For resinate sustained release tablets were formulated using hydoxypropyl methylcellulose K100M. The tablets were evaluated for hardness, thickness, friability, drug content, weight variation, and in vitro drug release. Tablets thus formulated (Batch T-3) provided sustained release of drug over a period of 12?h. The release of Betahistine HCl from resinate controls the diffusion of drug molecules through the polymeric material into aqueous medium. Results showed that Betahistine HCl was formulated into a sustained dosage form as an alternative to the conventional tablet. PMID:22779010

Wagh, Vijay D; Pawar, Nilesh

2012-01-01

2

Development and Evaluation of Sustained Release Tablet of Betahistine Hydrochloride Using Ion Exchange Resin Tulsion T344  

PubMed Central

An attempt was made to sustain the release of Betahistine hydrochloride by complexation technique using strong cation-exchange resin, Tulsion T344. The drug loading onto ion-exchange resin was optimized for mixing time, activation, effect of pH, swelling time, ratio of drug?:?resin, and temperature. The resinate was evaluated for micromeritic properties and characterized using XRPD and IR. For resinate sustained release tablets were formulated using hydoxypropyl methylcellulose K100M. The tablets were evaluated for hardness, thickness, friability, drug content, weight variation, and in vitro drug release. Tablets thus formulated (Batch T-3) provided sustained release of drug over a period of 12?h. The release of Betahistine HCl from resinate controls the diffusion of drug molecules through the polymeric material into aqueous medium. Results showed that Betahistine HCl was formulated into a sustained dosage form as an alternative to the conventional tablet.

Wagh, Vijay D.; Pawar, Nilesh

2012-01-01

3

Phosphonic acid based exchange resins  

DOEpatents

An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

Horwitz, E. Philip (Naperville, IL); Alexandratos, Spiro D. (Knoxville, TN); Gatrone, Ralph C. (Naperville, IL); Chiarizia, Ronato (Oak Park, IL)

1995-01-01

4

Phosphonic acid based exchange resins  

DOEpatents

An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 10 figs.

Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

1995-09-12

5

Phosphonic acid based ion exchange resins  

DOEpatents

An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 9 figures.

Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

1994-01-25

6

Phosphonic acid based ion exchange resins  

DOEpatents

An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene disphosphonic acid with styrene, acrylonitrile and divinylbenzene.

Horwitz, E. Philip (Naperville, IL); Alexandratos, Spiro D. (Knoxville, TN); Gatrone, Ralph C. (Naperville, IL); Chiarizia, Ronato (Oak Park, IL)

1994-01-01

7

Phosphonic acid based ion exchange resins  

DOEpatents

An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

Horwitz, E. Philip (Naperville, IL); Alexandratos, Spiro D. (Knoxville, TN); Gatrone, Ralph C. (Naperville, IL); Chiarizia, Ronato (Oak Park, IL)

1996-01-01

8

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs...Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin (hydrolized polyacrylamide), only for...

2012-04-01

9

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs...Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin (hydrolized polyacrylamide), only for...

2010-04-01

10

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs...Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin (hydrolized polyacrylamide), only for...

2011-04-01

11

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2013 CFR

...120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin (hydrolized polyacrylamide...copolymerization of acrylamide and acrylic acid with the greater part of the...Viscometer or equivalent using a number 6 spindle at 20...

2013-04-01

12

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2010 CFR

... 2009-04-01 2009-04-01 false Acrylamide-acrylic acid resins. 176.110 Section...Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely...

2009-04-01

13

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 2009-04-01 true Acrylamide-acrylic acid resins. 176.110 Section...Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely...

2010-01-01

14

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Acrylamide-acrylic acid resins. 176.110 Section 176.110 Food and...Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of...

2013-04-01

15

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Acrylamide-acrylic acid resins. 176.110 Section 176.110 Food and...Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of...

2011-04-01

16

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Acrylamide-acrylic acid resins. 176.110 Section 176.110 Food and...Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of...

2012-04-01

17

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2012 CFR

...Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260 Food...Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section and...

2012-04-01

18

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2011 CFR

...Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260 Food...Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section and...

2011-04-01

19

Binding of Bile Acids by Polymerized Cyclodextrin Resins  

Microsoft Academic Search

Copolymers of ?-cyclodextrin and epichlorohydrin were prepared by a crosslinking reaction of ?-cyclodextrin with different amounts of epichlorohydrin. These copolymers were tested for their ability to bind several bile salts (including the sodium salts of cholic acid, glycocholic acid, taurocholic acid, and chenodeoxycholic acid), individually and competitively, from phosphate buffer solutions at room temperature. The polymer resins with a lower

X. X. Zhu; F. Brizard; C. C. Wen; G. R. Brown

1997-01-01

20

Taste Mask, Design and Evaluation of an Oral Formulation Using Ion Exchange Resin as Drug Carrier  

Microsoft Academic Search

The purpose of this research was to mask the bitter taste of Diphenhydramine Hydrochloride (DPH) using cation exchange resins.\\u000a Indion 234 and Tulsion 343 that contained crosslinked polyacrylic backbone were used. The drug resin complexes (DRC) were\\u000a prepared by batch process by taking drug: resin ratios 1:1, 1:2, and 1:3. The optimum drug: resin ratio and the time required\\u000a for

Kiran Bhise; Shafi Shaikh; Divyakumar Bora

2008-01-01

21

Biomimetic Remineralization of Resin-bonded Acid-etched Dentin  

PubMed Central

Degradation of denuded collagen within adhesive resin-infiltrated dentin is a pertinent problem in dentin bonding. A biomimetic remineralization scheme that incorporates non-classic crystallization pathways of fluidic amorphous nanoprecursors and mesoscopic transformation has been successful in remineralizing resin-free, acid-etched dentin, with evidence of intrafibrillar and interfibrillar remineralization. This study tested the hypothesis that biomimetic remineralization provides a means for remineralizing incompletely infiltrated resin-dentin interfaces created by etch-and-rinse adhesives. The remineralization medium consists of a Portland cement/simulated body fluid that includes polyacrylic acid and polyvinylphosphonic acid biomimetic analogs for amorphous calcium phosphate dimension regulation and collagen targeting. Both interfibrillar and intrafibrillar apatites became readily discernible within the hybrid layers after 2-4 months. In addition, intra-resin apatite clusters were deposited within the porosities of the adhesive resin matrices. The biomimetic remineralization scheme provides a proof-of-concept for the adoption of nanotechnology as an alternative strategy to extend the longevity of resin-dentin bonds.

Tay, F.R.; Pashley, D.H.

2009-01-01

22

Formulation, Characterization and Evaluation of Rapid Disintegrating Tablet of atifloxacin Sesquihydrate by ion exchange resin technique  

Microsoft Academic Search

Gatifloxacin Sesquihydrate is a Broad Spectrum Antimicrobial agent active against Gram Positive and Gram Negative Organism. It is slightly bitter in taste. In the present study an attempt has been made to prepare bitterless fast dissolving tablet of Gatifloxacin Sesquihydrate using Indion 204, Indion 214, Indion 234, Tulsion 335 (ion exchange resin) as a taste masking agent. X-ray powder diffractometry,

P. S. Gangane; K. G. Mahajan; H. S. Sawarkar; V. S. Adhao

23

Treatment of DSD acid wastewater using a weak basic resin  

Microsoft Academic Search

The D301R resin was screened to separate DSD acid from DSD acid wastewater. The effect of pH, temperature and time on adsorption behavior was investigated. Batch experiments indicated that the COD removal ratio of DSD acid wastewater was over 86%, and the COD of treated wastewater was under 100 mg\\/L at appropriate operating conditions. The results of column dynamic adsorption

Li-min Chai; Feng-bao Zhang; Guo-liang Zhang

2005-01-01

24

Reactivity of Resorcinol Formaldehyde Resin with Nitric Acid  

SciTech Connect

Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. The threshold conditions promoting reaction have been identified. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

King, William D.; Fondeur, Fernando F.; Wilmarth, William R.; Pettis, Myra E.

2005-10-25

25

REACTIVITY OF RESORCINOL FORMALDEHYDE RESIN WITH NITRIC ACID  

SciTech Connect

Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

King, W; Fernando Fondeur, F; Bill Wilmarth, B; Myra Pettis, M; Shirley Mccollum, S

2006-06-14

26

Polymer resins with amino acid containing pendants for sorption of bilirubin. I. Comparison of Merrifield and polyamide resins.  

PubMed

Merrifield resins with various amino acid containing pendants and a water swellable polyamide resin with the peptide alanine-alanine-alanine-arginine as the pendant group have been prepared by solid phase peptide synthesis. Merrifield resins with either arginine or lysine pendants are capable of sorbing bilirubin from aqueous solution (pH = 7.8) but those with other amino acid pendants gave no indication of sorption. The polyamide-arginine resin showed, on a functional group basis, a higher capacity for bilirubin than does cholestyramine. It is proposed that the formation of salt linkages causes a strong interaction of bilirubin with arginine and lysine. PMID:6490193

Henning, D S; Lajoie, G A; Brown, G R; St-Pierre, L E; St-Pierre, S

1984-07-01

27

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2013 CFR

...purpose of this section, partial phosphoric acid esters of polyester resins are prepared by...of the resin thus produced with phosphoric acid anhydride to produce a resin having an acid number of 81 to 98 and a phosphorus content of...

2013-04-01

28

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2010 CFR

...purpose of this section, partial phosphoric acid esters of polyester resins are prepared by...of the resin thus produced with phosphoric acid anhydride to produce a resin having an acid number of 81 to 98 and a phosphorus content of...

2010-01-01

29

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2010 CFR

...purpose of this section, partial phosphoric acid esters of polyester resins are prepared by...of the resin thus produced with phosphoric acid anhydride to produce a resin having an acid number of 81 to 98 and a phosphorus content of...

2009-04-01

30

Preparation and Water Absorbent Behavior of Superabsorbent Polyaspartic Acid Resin  

Microsoft Academic Search

Superabsorbent polyaspartic acid (PASP) resin was prepared from high molecular weight polysuccinimide (PSI), which was synthesized\\u000a from l-aspartic acid by thermal polycondensation. The effects of the reaction temperature, the reaction time, the concentration\\u000a of the solvent, the molecular weight of PSI, the concentration of the cross-linking agent, the hydrolysis conditions, and\\u000a the drying temperature on the swelling ratio of PASP

Li Fang; Ying Zhao; Tian Wei Tan

2006-01-01

31

Preparation of strongly acidic cation-exchange resins from gymnosperm acid hydrolysis lignin  

Microsoft Academic Search

The chemical preparation of strongly acidic cation-exchange resin from sulfuric acid lignin (Klason lignin) (SAL), a typical\\u000a acid hydrolysis lignin, was investigated. Sulfonation of resinified SAL itself gave a resin with an ion-exchange capacity\\u000a of 2.3 mEq\\/g. After resinification with formaldehyde, the phenolized SAL with a reactivep-hydroxyphenyl group yielded a resin with an ion-exchange capacity of 3.2 mEq\\/g. The latter

Seiichi Yasuda; Kyoko Asano

2000-01-01

32

Fatty and resinic acids extractions from crude tall oil  

SciTech Connect

The separation of fatty and resinic acidic fractions from crude tall-oil soap solutions with n-heptane by the technique of dissociation extraction is discussed. The theory of the overall process is supported by a systematic study developed to cover the high selectivity demonstrated in the differential solubility and the aptness between fatty and diterpenic acids to both liquids phases. To study the main factors affecting those liquid-liquid extraction systems and the amphiphilic behavior of such molecules involved, sodium salts aqueous solutions of crude tall oil and synthetic mixtures as molecular acidic models were used.

Nogueira, J.M.F. [Univ. of Lisbon (Portugal)

1996-11-01

33

Comparison of XAD macroporous resins for the concentration of fulvic acid from aqueous solution  

USGS Publications Warehouse

Five macroreticular, nonlonlc AmberlHe XAD resins were evaluated for concentration and Isolation of fulvlc acid from aqueous solution. The capacity of each resin for fulvlc acid was measured by both batch and column techniques. Elution efficiencies were determined by desorptlon with 0.1 N NaOH. Highest recoveries were obtained with the acrylic ester resins which proved to be most efficient for both adsorption and elution of fulvlc acid. Compared to the acrylic ester resins, usefulness of the styrene dvlnybenzene resins to remove fulvlc acid is limited because of slow diffusion-controlled adsorption and formation of charge-transfer complexes, which hinders elution. ?? 1979 American Chemical Society.

Aiken, G. R.

1979-01-01

34

Polystyrene sulphonic acid resins with enhanced acid strength via macromolecular self-assembly within confined nanospace  

NASA Astrophysics Data System (ADS)

Tightening environmental legislation is driving the chemical industries to develop efficient solid acid catalysts to replace conventional mineral acids. Polystyrene sulphonic acid resins, as some of the most important solid acid catalysts, have been widely studied. However, the influence of the morphology on their acid strength—closely related to the catalytic activity—has seldom been reported. Herein, we demonstrate that the acid strength of polystyrene sulphonic acid resins can be adjusted through their reversible morphology transformation from aggregated to swelling state, mainly driven by the formation and breakage of hydrogen bond interactions among adjacent sulphonic acid groups within the confined nanospace of hollow silica nanospheres. The hybrid solid acid catalyst demonstrates high activity and selectivity in a series of important acid-catalysed reactions. This may offer an efficient strategy to fabricate hybrid solid acid catalysts for green chemical processes.

Zhang, Xiaomin; Zhao, Yaopeng; Xu, Shutao; Yang, Yan; Liu, Jia; Wei, Yingxu; Yang, Qihua

2014-01-01

35

Polystyrene sulphonic acid resins with enhanced acid strength via macromolecular self-assembly within confined nanospace.  

PubMed

Tightening environmental legislation is driving the chemical industries to develop efficient solid acid catalysts to replace conventional mineral acids. Polystyrene sulphonic acid resins, as some of the most important solid acid catalysts, have been widely studied. However, the influence of the morphology on their acid strength--closely related to the catalytic activity--has seldom been reported. Herein, we demonstrate that the acid strength of polystyrene sulphonic acid resins can be adjusted through their reversible morphology transformation from aggregated to swelling state, mainly driven by the formation and breakage of hydrogen bond interactions among adjacent sulphonic acid groups within the confined nanospace of hollow silica nanospheres. The hybrid solid acid catalyst demonstrates high activity and selectivity in a series of important acid-catalysed reactions. This may offer an efficient strategy to fabricate hybrid solid acid catalysts for green chemical processes. PMID:24463793

Zhang, Xiaomin; Zhao, Yaopeng; Xu, Shutao; Yang, Yan; Liu, Jia; Wei, Yingxu; Yang, Qihua

2014-01-01

36

Extractive lactic acid fermentation using ion-exchange resin.  

PubMed

Lactic acid fermentation is an end-product-inhibited reaction. The restriction imposed by lactic acid on its fermentation can be avoided by extractive fermentation techniques. Studies were performed by attaching an ion-exchange resin packed column with a 2-L fermentor for separation of lactic acid. The fermentation, in a conventional batch mode, resulted in a lactic acid yield of 0.828 g . g(-1) and a lactic acid productivity of 0.313 g . L(-1) . h(-1). However, these could be further enhanced to 0.929 g . g(-1) and 1.665 g . L(-1) . h(-1) by extractive fermentation techniques. The effect of temperature on extractive fermentation was remarkable and has been included in this work. PMID:18600989

Srivastava, A; Roychoudhury, P K; Sahai, V

1992-03-15

37

Characterization of stearic acid modified soy protein isolate resin and ramie fiber reinforced ‘green’ composites  

Microsoft Academic Search

The effects of stearic acid on the physical, tensile, moisture, thermal and micro-structural properties of the soy protein isolate (SPI)-based resin have been investigated. Fully biodegradable, environment-friendly, unidirectional, ramie fiber reinforced ‘green’ composites were also successfully fabricated using SPI and stearic acid modified SPI (MSPI) resins and characterized for their tensile and flexural properties. The fiber\\/resin interfacial shear strength was

Preeti Lodha; Anil N. Netravali

2005-01-01

38

Kinetics and molecular orbital calculations of desulfonation of strong acid cation-exchange resin  

Microsoft Academic Search

This paper deals with the desulfonation properties of some strong acid cation-exchange resins. The sulfate concentration in solution is continuously increased when a strong acid cation-exchange resin is mixed with water. The leaching of sulfate results from the desulfonation of the fixed group, and the amount of leached sulfate depends on the counter ion charge, the crosslinking degree and the

Takao Fujimori; Kousuke Kurisaki; Tadashi Okobira; Kazuya Uezu; Kazuhisa Yoshimura

2011-01-01

39

Enrichment and Purification of Total Chlorogenic Acids from Tobacco Waste Extract with Macroporous Resins  

Microsoft Academic Search

In the present study, an evaluation was conducted on the performance and separation characteristics of nine macroporous resins for the enrichment and purification of total chlorogenic acids from tobacco (Nicotiana tobaccum L.) waste extracts. Based on the results, XAD-4 offered higher adsorption and desorption capacities for total chlorogenic acids than other resins. To optimize the separation process of total chlorogenic

Zhao Hui; Wang Jun; Jia Jing; Liu Ji; Ling Xiuquan; Lu Dingqiang

2010-01-01

40

Green Biorefinery: Separation of lactic acid from grass silage juice by chromatography using neutral polymeric resin  

Microsoft Academic Search

The aim of this work was to recover lactic acid in undissociated form from grass silage juice. For this aim, chromatographic separation using neutral polymeric resin Amberlite XAD1600 was investigated. Up to now, there is no hint in the literatures about using neutral polymeric resin for lactic acid separation from a mixture. Important factors (flow-rate, concentration of feed and loaded

Vu Hong Thang; Senad Novalin

2008-01-01

41

Heterogeneous catalysis using a nanostructured solid acid resin based on lyotropic liquid crystals.  

PubMed

The catalytic reactivity and selectivity of the first example of a nanostructured solid acid resin (1) are described. This new type of solid acid catalyst is formed by the self-assembly and copolymerization of two acidic lyotropic liquid crystals (LLCs), affording a columnar hexagonal polymer network with monodisperse nanochannels lined with sulfonic acid groups. The performance of this material as a heterogeneous catalyst was compared against that of two commercially available, amorphous sulfonic acid resins: Amberlyst-15 and Nafion NR50. Using the acid-catalyzed esterification of benzyl alcohol with 1-hexanoic acid in dry toluene as a test reaction, it was found that resin 1 displayed only slightly lower overall reactivity as compared to Amberlyst-15 and Nafion NR50 but more than an order of magnitude higher selectivity for the desired ester product over dibenzyl ether side-product. Control experiments revealed that the higher product selectivity is not due to differences in relative acidity between the nanostructured acid resin and the two amorphous resins. Instead, it appears that a large component of the enhanced selectivity is due to the regular nanostructure present in the LLC resin, which affords a much more uniform local acid microenvironment for reactions to occur. Resin 1 can also be recycled with almost complete recovery of catalytic activity and selectivity, and with essentially no leaching of reactive groups into the solution phase. PMID:14871076

Xu, Yanjie; Gu, Weiqiang; Gin, Douglas L

2004-02-18

42

Thermochemical comparisons of homogeneous and heterogeneous acids and bases. 1. Sulfonic acid solutions and resins as prototype Broensted acids  

SciTech Connect

Heats of ionization by thermometric titration for a series of bases (or acids) can be used to compare solid acids (or bases) with liquid analogues bearing the same functionalities in homogeneous solutions. The method is demonstrated for Broensted acids by reacting a series of substituted nitrogen bases with solutions of p-toluenesulfonic acid (PTSA) in acetonitrile and with suspensions of the microporous polymeric arylsulfonic acid resin-Dowex 50W-X8 in the same solvent. Under well-controlled anhydrous conditions there is a good correlation (r = 0.992) between the heats of reaction of the bases with the homogeneous and heterogeneous acid systems, but the homogeneous system gives a more exothermic interaction by 3-4 kcal mol/sup -1/ for a series of 29 substituted pyrimidines, anilines, and some other amines. This difference may be attributed to homohydrogen bonding interactions between excess acid and sulfonate anion sites which are more restricted geometrically in the resin than in solution. Other factors which affect the enthalpy change for the acid-base interaction are the acid/base ratio, the water content of the sulfonic acid, the solvent, and the resin structure (e.g., microporous vs. macroporous). Steric hindrance in the base does not differentiate solid from homogeneous acid. In addition to the use of titration calorimetry, heats of immersion are reported for the Dowex-arylsulfonic acid resins and the Nafion-perfluorinated sulfonic acid resin in a series of basic liquids. The results are compared with each other and with those from a previous study of several varieties of coal.

Arnett, E.M.; Haaksma, R.A.; Chawla, B.; Healy, M.H.

1986-08-06

43

Isolation of organic acids from large volumes of water by adsorption on macroporous resins  

USGS Publications Warehouse

Adsorption on synthetic macroporous resins, such as the Amberlite XAD series and Duolite A-7, is routinely used to isolate and concentrate organic acids from forge volumes of water. Samples as large as 24,500 L have been processed on site by using these resins. Two established extraction schemes using XAD-8 and Duolite A-7 resins are described. The choice of the appropriate resin and extraction scheme is dependent on the organic solutes of interest. The factors that affect resin performance, selectivity, and capacity for a particular solute are solution pH, resin surface area and pore size, and resin composition. The logistical problems of sample handling, filtration, and preservation are also discussed.

Aiken, George R.

1987-01-01

44

Bifunctional phenyl monophosphonic/sulfonic acid ion exchange resin and process for using the same  

DOEpatents

A cross-linked water-insoluble ion exchange resin comprised of polymerized monomers having a phenyl ring is disclosed. A contemplated resin contains (i) polymerized phenyl ring-containing monomers having a phosphonic acid ligand linked to the phenyl ring, (ii) about 2 to about 5 millimoles per gram (mmol/g) of phosphorus as phosphonic acid ligands, and (iii) a sufficient amount of a sulfonic acid ligand such that the ratio of mmol/g of phosphonic acid to mmol/g sulfonic acid is up to 3:1. A process for removing polyvalent metal cations from aqueous solution, and a process for removing iron(III) cations from acidic copper(II) cation-containing solutions that utilize the contemplated resin or other resins are disclosed.

Alexandratos, Spiro (Knoxville, TN); Shelley, Christopher A. (Knoxville, TN); Horwitz, E. Philip (Naperville, IL); Chiarizia, Renato (Elmhurst, IL); Gula, Michael J. (Chicago, IL); Xue, Sui (Darien, IL); Harvey, James T. (Naperville, IL)

2002-01-01

45

Bifunctional phenyl monophosphonic/sulfonic acid ion exchange resin and process for using the same  

DOEpatents

A cross-linked water-insoluble ion exchange resin comprised of polymerized monomers having a phenyl ring is disclosed. A contemplated resin contains (i) polymerized phenyl ring-containing monomers having a phosphonic acid ligand linked to the phenyl ring, (ii) about 2 to about 5 millimoles per gram (mmol/g) of phosphorus as phosphonic acid ligands, and (iii) a sufficient amount of a sulfonic acid ligand such that the ratio of mmol/g of phosphonic acid to mmol/g sulfonic acid is up to 3:1. A process for removing polyvalent metal cations from aqueous solution, and a process for removing iron(III) cations from acidic copper(II) cation-containing solutions that utilize the contemplated resin or other resins are disclosed.

Alexandratos, Spiro (Knoxville, TN); Shelley, Christopher A. (Knoxville, TN); Horwitz, E. Philip (Naperville, IL); Chiarizia, Renato (Elmhurst, IL)

2001-01-01

46

The effect of phosphoric acid concentration on resin tag length and bond strength of a photo-cured resin to acid-etched enamel  

Microsoft Academic Search

Objectives: To determine the relationship between depth of penetration and tensile bond strength of a photo-cured resin to phosphoric acid etched enamel, and the efficacy of enamel etchants that are less aggressive than a concentration of 10% H3PO4.Methods: The tensile bond strength and length of tags produced by a photo-cured (20s) resin consisting of pre-polymerized TMPT\\/silica in 3% HNPM–TEGDMA on

M. J. Shinchi; K. Soma; N. Nakabayashi

2000-01-01

47

Vacancy ion-exclusion chromatography of haloacetic acids on a weakly acidic cation-exchange resin.  

PubMed

A new and simple approach is described for the determination of the haloacetic acids (such as mono-, di- and trichloroacetic acids) usually found in drinking water as chlorination by-products after disinfection processes and acetic acid. The new approach, termed vacancy ion-exclusion chromatography, is based on an ion-exclusion mechanism but using the sample solution as the mobile phase, pure water as the injected sample, and a weakly acidic cation-exchange resin column (TSKgel OApak-A) as the stationary phase. The addition of sulfuric acid to the mobile phase results in highly sensitive conductivity detection with sharp and well-shaped peaks, leading to excellent and efficient separations. The elution order was sulfuric acid, dichloroacetic acid, monochloroacetic acid, trichloroacetic acid, and acetic acid. The separation of these acids depends on their pKa values. Acids with lower pKa values were eluted earlier than those with higher pKa, except for trichloroacetic acid due to a hydrophobic-adsorption effect occurring as a side-effect of vacancy ion-exclusion chromatography. The detection limits of these acids in the present study with conductivity detection were 3.4 microM for monochloroacetic acid, 0.86 microM for dichloroacetic acid and 0.15 microM for trichloroacetic acid. PMID:12830885

Helaleh, Murad I H; Tanaka, Kazuhiko; Mori, Masanobu; Xu, Qun; Taoda, Hiroshi; Ding, Ming-Yu; Hu, Wenzhi; Hasebe, Kiyoshi; Haddad, Paul R

2003-05-16

48

Lewis AcidBase Properties of a Gel-type Cation Exchange Resin  

Microsoft Academic Search

Gel-type cation exchange resins like SK-1B are based on DVB-crosslinked polystyrene with sulfonic acid functional groups. The behavior of some conjugate acid-base pairs was studied and explained in terms of Lewis and Pearson Acid-Base Theories. The application of these resins as a no contaminant medium for pH regulation has special interest in biological systems and is not limited to water

E. Ocampo; E. Cagnola; S. Alconchel; N. Piovano; G. Papa; H. Andrada; J. Verdura; M. Dapueto

1996-01-01

49

Adsorption of phenol and benzoic acid from dilute aqueous solution onto macroreticular resin  

Microsoft Academic Search

The adsorption of phenol and benzoic acid from dilute aqueous solution onto macroreticular resin was studied by a radiotracer technique for 0.4948-0.0003 mg\\/ml benzoic acid solutions at 25°C and for similar concentrations of phenol at 0°, 25°, and 70°C. Adsorption equilibrium with the Amberlite XAD-8 resin slurry was reached after 44 hr for benzoic acid and after 104 hr for

D. S. Farrier; A. L. Hines; S. W. Wang

1979-01-01

50

Biological degradation of resin acids in wood chips by wood-inhabiting fungi.  

PubMed Central

Resin acids in many pulp mill effluents are primary sources of toxicity to fish. Inconsistent biological detoxification of chlorinated and nonchlorinated resin acids in secondary treatment of pulp mill effluents is a continuing source of concern. An alternative approach to effluent detoxification is to remove or modify the toxic compounds present in wood chips prior to pulping. Results from experiments in which lodgepole pine sapwood chips were inoculated with several fungal candidates indicate that the total resin acid content can be reduced by up to 67% after fungal growth. Such a treatment could be an efficient and environmentally acceptable way for deresinating wood chips and so decreasing the toxicity of pulp mill effluents.

Wang, Z; Chen, T; Gao, Y; Breuil, C; Hiratsuka, Y

1995-01-01

51

Radiation curing of polyester resin modified with acrylic acid and its salts  

NASA Astrophysics Data System (ADS)

Polyester resin containing acrylic acid or its salts was cured with ? 60Co radiation. The course of curing was examined, the gel content and polymerization shrinkage were measured and also thermographic and IR absorption analyses were carried out. It was found that manganese, iron and copper acrylates inhibited the curing of resin while the remaining additives showed a slightly stimulating action. All the additives decreased the polymerization shrinkage by a factor of 2-3 and iron acrylate by as much as 8 times (up to 1%). They also increased the activation energy of the thermal decomposition of resin, and calcium, barium and copper acrylates increased the thermal stability of resin by 20 K. IR absorption spectra showed that acrylic acid and its salts reacted mainly with the monomeric component of the resin (styrene) whereas iron and copper acrylates first attacked the unsaturated bonds of the oligoester.

Szali?ska, H.; Pietrzak, M.; Janowska, G.

52

Chemically modified polymeric resins for separation of cations, organic acids, and small polar moleculea by high performance liquid chromatography.  

National Technical Information Service (NTIS)

This thesis is divided into 4 parts: a review, ion chromatography of metal cations on carboxylic resins, separation of hydrophilic organic acids and small polar compounds on macroporous resin columns, and use of eluent modifiers for liquid chromatographic...

J. B. Morris

1993-01-01

53

Studies on the Sorption of Palladium using Cross?Linked Poly (4?Vinylpyridine?Divinylbenzene) Resins in Nitric Acid Medium  

Microsoft Academic Search

Various cross?linked (4, 8, and 12%) gel?type weak?base poly(4?vinylpyridine) (PVP) resins were studied for palladium recovery from nitric acid medium. The sorption of palladium was found to decrease with an increase in cross?linkage of the resin. 8 and 12% PVP resins exhibited maximum DPd(II) values at 2–6 M HNO3, whereas 4% PVP resin showed maximum DPd(II) values at lower acidities (0.1 M

R. Kumaresan; K. N. Sabharwal; T. G. Srinivasan; P. R. Vasudeva Rao; Gunesh Dhekane

2008-01-01

54

Epoxidation of Canola Oil with Hydrogen Peroxide Catalyzed by Acidic Ion Exchange Resin  

Microsoft Academic Search

Canola oil with an iodine value of 112\\/100 g, and containing 60% oleic acid and 20% linoleic acid, was epoxidised using a\\u000a peroxyacid generated in situ from hydrogen peroxide and a carboxylic acid (acetic or formic acid) in the presence of an acidic\\u000a ion exchange resin (AIER), Amberlite IR 120H. Acetic acid was found to be a better oxygen carrier than

Rubeena Mungroo; Narayan C. Pradhan; Vaibhav V. Goud; Ajay K. Dalai

2008-01-01

55

Separation of aliphatic carboxylic acids and benzenecarboxylic acids by ion-exclusion chromatography with various cation-exchange resin columns and sulfuric acid as eluent  

Microsoft Academic Search

The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1–C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic

Kazutoku Ohta; Masayoshi Ohashi; Ji-Ye Jin; Toyohide Takeuchi; Chuzo Fujimoto; Seong-Ho Choi; Jae-Jeong Ryoo; Kwang-Pill Lee

2003-01-01

56

Intermediates to ethylene glycol: carbonylation of formaldehyde catalyzed by Nafion solid perfluorosulfonic acid resin  

SciTech Connect

Details of a series of reactions for the production of ethylene glycol using a catalyst of Nafion solid perfluorosulfonic acid resin was detailed. The reactions included the carbonylation of formaldehyde and esterification and then hydrogenation of the product of the carbonylation, glycolic acid. Other preparations included in the work included methyl glycolate, acetylglycolic acid, methyl acetylglycolate, and methyl methoxyacetate.

Hendriksen, D.E.

1983-01-01

57

Two new glycosidic acids, quamoclinic acids G and H, of the resin glycosides (Convolvulin) from the seeds of Quamoclit pennata.  

PubMed

Two new glycosidic acids, quamoclinic acids G and H, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit pennata BOJER. Both compounds are the first examples of bisdesmosides of glycosidic acid having the sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at its C-11. PMID:20823606

Ono, Masateru; Imao, Masae; Miyahara, Kazumoto

2010-09-01

58

The synergistic effect between hydrophobic and electrostatic interactions in the uptake of amino acids by strongly acidic cation-exchange resins  

Microsoft Academic Search

The goal of this work was to investigate the synergistic effect between the electrostatic and hydrophobic interactions upon the uptake of organic ions with hydrophobic moieties by ion-exchange resins with hydrophobic matrixes. The uptake of neutral amino acids by a macroporous polystyrene-based strongly acidic cation-exchange resin (D001) and two strongly acidic cation-exchange resins (poly(2-acrylamido-2-methyl propanesulfonic acid) and poly(vinylsulfonic acid)) with

Shaoling Cheng; Husheng Yan; Changqing Zhao

2006-01-01

59

Processing and composition control of weak-acid-resin-derived fuel microspheres  

Microsoft Academic Search

The current recycle fissile fuel for steam cycle high-temperature gas-cooled reactors in the U.S. is derived from weak acid ion-exchange resin microspheres loaded with uranyl ions. This material offers great versatility in the control of chemical and physical properties through careful process control. Processing the upgraded loaded resin begins with thermal decomposition or carbonization, which yields finely dispersed UOâ in

G. W. Weber; R. L. Beatty; V. J. Tennery

1977-01-01

60

Fatty Acid-Based Monomers as Styrene Replacements for Liquid Molding Resins.  

National Technical Information Service (NTIS)

One method of reducing styrene emissions from vinyl ester (VE) and unsaturated polyester resins (UPE) is to replace some or all of the styrene with fatty acid-based monomers. Methacrylated fatty acid (MFA) monomers are ideal candidates because they are in...

J. J. La Scala J. M. Sands J. A. Orlicki G. R. Palmese E. J. Robinette

2005-01-01

61

Vacancy ion-exclusion chromatography of inorganic acids on a weakly acidic cation-exchange resin column.  

PubMed

Vacancy ion-exclusion chromatography (VIEC) for inorganic acids such as H(2)SO(4), HCl, H(3)PO(4), HNO(3), HI and HF is tested on a polymethacrylate-based weakly acidic cation-exchange resin column in the H(+)-form. That is, mixture of inorganic acids in the mobile phase is adsorbed to the resin phase passing through the separation column, and each vacant peak induced by injecting water is determined. Retention times are dependent on the degrees of retention for each analyte in the resin phase. In VIEC, well-shaped peaks of inorganic acids are produced, leading to efficient separations. However, retention behaviors of inorganic acids were strongly affected by the concentrations of the acids in the mobile phase. Sulfosalicylic acid was mixed with inorganic acids in the mobile phase prior to the introduction of a separation column in order to obtain the well-resolutions in the lower concentrations of the acids. By using this method, the separations of inorganic acids could be achieved in the range of 0.01-1 mM, and the linear ranges could be extended over two-orders of magnitude. This is considered since the protonated carboxylic groups fixed on the resin phase were increased with increasing the acid concentrations in the mobile phase, and the penetration effects for the acids to the resin phase were thus enhanced. The detection limits (S/N=3) were below 1.0 microM for all analyte acids. Precision values for retention times were below 0.32% and for peak area were below 0.91%. PMID:16472541

Mori, Masanobu; Itabashi, Hideyuki; Helaleh, Murad I H; Kaczmarski, Krzysztof; G?ód, Bronis?aw; Kowalska, Teresa; Xu, Qun; Ikedo, Mikaru; Hu, Wenzhi; Tanaka, Kazuhiko

2006-06-16

62

Adsorptive Membranes vs. Resins for Acetic Acid Removal from Biomass Hydrolysates  

SciTech Connect

Acetic acid is a compound commonly found in hemicellulosic hydrolysates. This weak acid strongly influences the bioconversion of sugar containing hydrolysates. Previous investigators have used anion exchange resins for acetic acid removal from different hemicellulosic hydrolysates. In this study, the efficiency of an anion exchange membrane was compared to that of an anion exchange resin, for acetic acid removal from a DI water solution and an acidic hemicellulose hydrolysate pretreated using two different methods. Ion exchange membranes and resins have very different geometries. Here the performance of membranes and resins is compared using two dimensionless parameters, the relative mass throughput and chromatographic bed number. The relative mass throughput arises naturally from the Thomas solution for ion exchange. The results show that the membrane exhibit better performance in terms of capacity, and loss of the desired sugars. In addition acetic acid may be eluted at a higher concentration from the membrane thus leading to the possibility of recovery and re-use of the acetic acid.

Han, B.; Carvalho, W.; Canilha, L.; da Silva, S. S.; e Silva, J. B. A.; McMillan, J. D.; Wickramasinghe, S. R.

2006-01-01

63

Diterpene resin acids: Major active principles in tall oil against Variegated cutworm,Peridroma saucia (Lepidoptera: Noctuidae).  

PubMed

Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45-60% compared to controls. This suppression was significantly (P?0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil. PMID:24249127

Xie, Y; Isman, M B; Feng, Y; Wong, A

1993-06-01

64

Preparation of anion-exchange resins from pine sulfuric acid lignin, one of the acid hydrolysis lignins  

Microsoft Academic Search

To utilize acid hydrolysis lignin effectively, chemical conversion to anion-exchange resin was investigated by two methods. Sulfuric acid lignin (SAL) was selected as a typical acid hydrolysis lignin in this experiment. Because it is less reactive, SAL was phenolated with sulfuric acid catalyst to yield reactive phenolized SAL (P-SAL) with p-hydroxyphenyl nuclei. One method was the restricted resinification of P-SAL

Yasuyuki Matsushita; Seiichi Yasuda

2003-01-01

65

Sorption of Pu(IV) from nitric acid by bifunctional anion-exchange resins  

SciTech Connect

Anion exchange is attractive for separating plutonium because the Pu(IV) nitrate complex is very strongly sorbed and few other metal ions form competing anionic nitrate complexes. The major disadvantage of this process has been the unusually slow rate at which the Pu(IV) nitrate complex is sorbed by the resin. The paper summarizes the concept of bifunctional anion-exchange resins, proposed mechanism for Pu(IV) sorption, synthesis of the alkylating agent, calculation of K{sub d} values from Pu(IV) sorption results, and conclusions from the study of Pu(IV) sorption from 7M nitric acid by macroporous anion-exchange resins including level of crosslinking, level of alkylation, length of spacer, and bifunctional vs. monofunctional anion-exchange resins.

Bartsch, R.A.; Zhang, Z.Y.; Elshani, S.; Zhao, W. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry and Biochemistry; Jarvinen, G.D.; Barr, M.E.; Marsh, S.F.; Chamberlin, R.M. [Los Alamos National Lab., NM (United States). Nuclear Materials Technology Div.

1999-06-01

66

Liquid-phase synthesis of ethyl tert-butyl ether over acid cation-exchange inorganic–organic resins  

Microsoft Academic Search

In this study the possibility to increase the productivity of acid cation-exchange resin catalysts active sites in ETBE synthesis was elucidated. For this purpose the inorganic–organic sulfonated cation-exchange resins with different polymer loadings (1.5–9.2wt.%) have been synthesized. Such polymer\\/carrier composites as well as commercial acidic microporous gel-type ion-exchange resin KU-2-8 and macroporous Amberlyst 15 have been studied in the ETBE

N. V. Vlasenko; Yu. N. Kochkin; A. V. Topka; P. E. Strizhak

2009-01-01

67

Effect of acid groups in hydroxyl functional resins on the properties of polyester-urethane powder coatings  

Microsoft Academic Search

Hydroxyl-terminated polyester resins with different acid numbers were synthesized and used in powder coating formulations.\\u000a Coatings were formulated with isophorone diisocyanate (IPDI)-based hardeners and tested for mechanical performance, appearance,\\u000a and weathering. This study found that resins containing a high concentration of residual acid groups (also referred to as\\u000a undercondensed resins) had to be formulated according to their total reactive number,

Bin Wu; Sanjay Padaki; Daniel Maetens

2000-01-01

68

Chemically modified polymeric resins for separation of cations, organic acids, and small polar moleculea by high performance liquid chromatography  

SciTech Connect

This thesis is divided into 4 parts: a review, ion chromatography of metal cations on carboxylic resins, separation of hydrophilic organic acids and small polar compounds on macroporous resin columns, and use of eluent modifiers for liquid chromatographic separation of carboxylic acids using conductivity detection.

Morris, J.B.

1993-07-01

69

Wang-aldehyde resin as a recyclable support for the synthesis of alpha,alpha-disubstituted amino acid derivatives.  

PubMed

Merrifield resin was functionalised with hydroxybenzaldehyde under microwave irradiation. The resultant resin was used as a means for immobilisation and activation of alpha-amino acid esters for alkylation reactions. Alpha,alpha-disubstituted and cyclic amino acid esters were prepared in good yields. PMID:16106300

Guinó, Meritxell; Hii, King Kuok Mimi

2005-09-01

70

Gas chromatographic determination of organic acids from fruit juices by combined resin mediated methylation and extraction in supercritical carbon dioxide  

Microsoft Academic Search

A procedure in which anionic analytes, trapped on ion exchange resin, are simultaneously methylated and released using methyl iodide in either supercritical carbon dioxide or acetonitrile has been extended to polyfunctional organic acids. The combined SFE methylation of fruit juice acids trapped onto ion exchange resin proceeds in good yield producing the methyl esters of fumaric, succinic, malic, tartaric, isocitric

Timothy J. Barden; Marguerite Y. Croft; E. John Murby; Robert J. Wells

1997-01-01

71

Application of hydrophobic resin adhesives to acid-etched dentin with an alternative wet bonding technique.  

PubMed

Hydrophilic dentin adhesives are prone to water sorption that adversely affects the durability of resin-dentin bonds. This study examined the feasibility of bonding to dentin with hydrophobic resins via the adaptation of electron microscopy tissue processing techniques. Hydrophobic primers were prepared by diluting 2,2-bis[4(2-hydroxy-3-methacryloyloxy-propyloxy)-phenyl] pro- pane/triethyleneglycol dimethacrylate resins with known ethanol concentrations. They were applied to acid-etched moist dentin using an ethanol wet bonding technique that involved: (1) stepwise replacement of water with a series of increasing ethanol concentrations to prevent the demineralized collagen matrix from collapsing; (2) stepwise replacement of the ethanol with different concentrations of hydrophobic primers and subsequently with neat hydrophobic resin. Using the ethanol wet bonding technique, the experimental primer versions with 40, 50, and 75% resin exhibited tensile strengths which were not significantly different from commercially available hydrophilic three-step adhesives that were bonded with water wet bonding technique. The concept of ethanol wet bonding may be explained in terms of solubility parameter theory. This technique is sensitive to water contamination, as depicted by the lower tensile strength results from partial dehydration protocols. The technique has to be further improved by incorporating elements of dentin permeability reduction to avoid water from dentinal tubules contaminating water-free resin blends during bonding. PMID:17600324

Sadek, Fernanda T; Pashley, David H; Nishitani, Yoshihiro; Carrilho, Marcella R; Donnelly, Adam; Ferrari, Marco; Tay, Franklin R

2008-01-01

72

Recovery of plutonium from nitric acid containing oxalate and fluoride by a macroporous bifunctional phosphinic acid resin (MPBPA)  

Microsoft Academic Search

Summary  The sorption of Pu from nitric acid solutions containing oxalate\\/fluoride was studied using an indigenously available macroporous\\u000a bifunctional phosphinic acid (MPBPA) resin. Batch experiments were carried out to obtain the distribution data of Pu(IV) with\\u000a a view to optimize conditions for its recovery from nitric acid waste solutions containing oxalate or fluoride ions. The measurements\\u000a showed high distribution ratio (D)

K. Venugopal Chetty; A. G. Godbole; R. Swarup; V. N. Vaidya; V. Venugopal; P. R. Vasudeva Rao

2005-01-01

73

Exposure to Wood Dust, Resin Acids, and Volatile Organic Compounds During Production of Wood Pellets  

Microsoft Academic Search

The main aim of this study was to investigate exposure to airborne substances that are potentially harmful to health during the production of wood pellets, including wood dust, monoterpenes, and resin acids, and as an indicator of diesel exhaust nitrogen dioxide. In addition, area measurements were taken to assess background exposure levels of these substances, volatile organic compounds (VOCs), and

Katja Hagström; Sara Axelsson; Helena Arvidsson; Ing-Liss Bryngelsson; Cecilia Lundholm; Kåre Eriksson

2008-01-01

74

Exposure to Dust, Resin Acids, and Monoterpenes in Softwood Lumber Mills  

Microsoft Academic Search

A study to assess exposure to potential respiratory hazards in a large lumber mill processing spruce (Picea engelmannii and glauca), pine (Pinus contorta), and fir (Abies lasiocarpa) used a random sampling strategy to assess exposures for all jobs in the sawmill, planer mills, and yard. Personal samples for inhalable particulate were collected to measure exposure to dust and resin acids

Paul A. Demers; Kay Teschke; Hugh W. Davies; Susan M. Kennedy; Victor Leung

2000-01-01

75

Purification of dilute hydrofluoric acid by commercial ion exchange resins  

Microsoft Academic Search

This paper describes the results from an experimental study of the purification of dilute hydrofluoric acid (5wt.%) by ion exchange. Hydrofluoric acid was prepared by dilution from technical grade concentrated HF; important amounts of metal impurities were found in the diluted acid, mainly Na, Fe, As, B, Ca, K, Mg, Mn, Mo, PO43?, and Ti. The semiconductor industry developed the

I. Fernández-Olmo; J. L. Fernández; A. Irabien

2007-01-01

76

Preparation, Acid Curing, and Thermal Stability of Various Formulated Phenolic Resole Resins: Unfilled and Nanocomposites  

Microsoft Academic Search

Several phenol-formaldehyde resole resins were prepared with variety in monomers ratio, catalyst type, and content, having different nanoclay levels; then they were cured using various acids in the wide range of concentration. The acid-curing process was studied, considering gel time (tG) and cure time (tC). In addition, the thermal stability was investigated before and after cure for all samples. With

Foroozan Kassebi; Bakhtiar Mammadov; Somayyeh Mohammadian-Gezaz

2012-01-01

77

An approach to improve the application of acid-insoluble lignin from rice hull in phenol–formaldehyde resin  

Microsoft Academic Search

The study was based on the yield of ligninphenol and the resins, morphology, temperature stability, water and ultraviolet resistance of the formulated resins, to describe a route to improve the potential for partially replacing phenol with rice hull acid-insoluble lignin in phenol–formaldehyde (PF) resin. In this route, phenolation and three-step polymerization were combined to increase the reactivity of rice hull

Yuejia Ma; Xu Zhao; Xue Chen; Zichen Wang

2011-01-01

78

Acidic resin-catalysed conversion of fructose into furan derivatives in low boiling point solvents.  

PubMed

Conversion of fructose into furan derivatives 5-hydroxymethylfurfural (HMF) and 5-methoxymethylfurfural (MMF) is performed in tetrahydrofuran (THF) and methanol-organic solvent systems, catalysed by an acidic resin Amberlyst-15. The melted fructose can be converted into HMF on the surface of the solid resin catalyst in the presence of THF as an extracting phase, which is a good solvent for HMF and other by-products. The solid resin catalyst can be reused eleven times without losing its catalytic ability, with an average HMF yield of approximately 50%. Upon the addition of methanol, the generated HMF can further react with methanol to form MMF, and the total yield of HMF and MMF could be promoted to 65%. GC-MS analysis confirms the formation of a small amount of methyl levulinate in methanolorganic solvent system. PMID:21741626

Zhu, Hong; Cao, Quan; Li, Chunhu; Mu, Xindong

2011-09-27

79

Acute effects of chlorinated resin acid exposure on juvenile rainbow trout, Oncorhynchus mykiss  

SciTech Connect

The effects of an acute exposure to either 14-monochlorodehydroabietic acid (MCDHAA) or 12,14-dichlorodehydroabietic acid (DCDHAA) were examined in juvenile rainbow trout, Oncorhynchus mykiss. The experimentally determined 96-h LC50 values (and their 95% confidence limits) were 1.03 (0.72, 1.48) and 0.91 (0.70, 1.21) mg/L, for MCDHAA and DCDHAA, respectively. To measure effects on several biochemical parameters, swimming performance, and disease resistance, juvenile trout were exposed for 24 h to sublethal concentrations of one or the other resin acid in an intermittent-flow respirometer. Hematocrit, plasma lactate, and liver protein were significantly affected by exposure to the highest dose (80% of the 96-h LC50 value) of either of the resin acids. Plasma cortisol levels were 14- and 3-fold higher than were controls. Resistance to infection by Aeromonas salmonicida was significantly reduced; the cumulative percent mortalities due to furunculosis in fish exposed to MCDHAA or DCDHAA reached 20 and 26%, respectively. Swimming performance, measured as critical swimming speed (mean values 6.32 {+-} 0.20 and 5.93 {+-} 0.15 body lengths per second for MCDHAA and DCDHAA, respectively), was not significantly affected by resin acid exposure.

Kennedy, C.J.; Sweeting, R.M.; Farrell, A.P.; McKeown, B.A. [Simon Fraser Univ., Burnaby, British Columbia (Canada). Dept. of Biological Sciences; Johansen, J.A. [BioWest Environmental Research Consultants, Burnaby, British Columbia (Canada)

1995-06-01

80

Enhanced sorption of bisphenol A on ?-ketoglutaric acid-modified chitosan resins by hydrophobic sorption of hemimicelles  

Microsoft Academic Search

In this paper, ?-ketoglutaric acid-modified chitosan resins (KCR) were successfully prepared. The capacity of KCR as weak cation exchanger for sorbing bisphenol A (BPA) from aqueous solution was compared with crosslinked chitosan resins (CCR) with cetyl trimethyl ammonium bromide (CTAB) as the intermediary of BPA sorbed on sorbent. The BPA removal was found to be dependent on the initial pH,

Renmin Gong; Yan Jiang; Wenkai Cai; Ke Zhang; Bo Yuan; Jihong Jiang

2010-01-01

81

Siloxyl ether functionalized resins for chemoselective enrichment of carboxylic acids.  

PubMed

Although the carboxylic acid moiety is prevalent in many biologically produced molecules, including natural products and proteins, methods to chemoselectively target this functional group have remained elusive. Generally, strategies that utilize carboxylate nucleophilicity also promote reactions with other nucleophiles such as amines and hydroxyls. A reagent was sought to facilitate the selective isolation of carboxylic acid containing compounds from complex mixtures. Here, the development of siloxyl ether functionalized solid supports is described. PMID:21957886

Trader, Darci J; Carlson, Erin E

2011-10-21

82

Identification and characterization of component organic and glycosidic acids of crude resin glycoside fraction from Calystegia soldanella.  

PubMed

Alkaline hydrolysis of the crude resin glycoside fraction of the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae) gave four new glycosidic acids, named calysolic acids A, B, C, and D, along with one known glycosidic acid, soldanellic acid B, and three organic acids, 2S-methylbutyric, tiglic, and 2S,3S-nilic acids. The structures of the new glycosidic acids were characterized on the basis of spectroscopic data and chemical evidence. PMID:21881263

Takigawa, Ayako; Setoguchi, Hiroaki; Okawa, Masafumi; Kinjo, Junei; Miyashita, Hiroyuki; Yokomizo, Kazumi; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ono, Masateru

2011-01-01

83

Uranium dispersion in the coating of weak-acid-resin-deprived HTGR fuel microspheres  

Microsoft Academic Search

The current reference HTGR recycle fuel particle is a UO\\/UC$sub ; 2$ kernel with a Triso coating comprising a low-density pyrocarbon (PyC) buffer, ; a high-density PyC inner LTI coating, SiC, and a high-density PyC outer LTI. The ; kernel is fabricated from a weak-acid ion exchange resin (WAR). ; Microradiographic examination of coated WAR particles has demonstrated that ;

G. W. Weber; R. L. Beatty; V. J. Tennery; W. J. Jr. Lackey

1976-01-01

84

Hydroxyl and acid number prediction in polyester resins by near infrared spectroscopy and artificial neural networks  

Microsoft Academic Search

Back-propagation artificial neural networks (BP-ANN) are applied for modeling hydroxyl number and acid value of a set of 62 samples of polyester resins from their near infrared (NIR) spectra. The results are compared to the classical calibration approaches, i.e. principal component regression (PCR) and partial least squares (PLS). The set of available samples is split into: (i) a training set,

Emilio Marengo; Marco Bobba; Elisa Robotti; Marcello Lenti

2004-01-01

85

Mechanism of 1-butene hydration over acidic zeolite and ion-exchange resin catalysts  

Microsoft Academic Search

Vapour-phase hydration of 1-butene at atmospheric pressure above 373 K shows similar features on both H-clinoptilolite and sulphonic acid ion-exchange resin: the initial reaction rate linearly increases with the partial pressure of 1 -butene and passes through a maximum as a function of water pressure. Kinetics was evaluated accordingly. A decrease in the 1-butene isomerization rate indicated that under hydration

Dénes Kalló; R. Magdolna Mihályi

1995-01-01

86

Acrylic acid removal by acrylic acid utilizing bacteria from acrylonitrile-butadiene-styrene resin manufactured wastewater treatment system.  

PubMed

The aim of this study is to isolate the acrylic acid utilizing bacteria from the ABS resin manufactured wastewater treatment system. The bacteria should have the ability to remove acrylic acid and tolerate the acrylonitrile and acrylamide toxicity. The aim is also to understand the performance of isolated pure strain for treating different initial acrylic acid concentrations from synthetic wastewater. The results are: twenty strains were isolated from the ABS resin manufactured wastewater treatment system and twelve of them could utilize 600 mg/l acrylic acid for growth. Seven of twelve strains could tolerate the acrylonitrile and acrylamide toxicity, when the concentration was below 300 mg/l. Bacillus thuringiensis was one of the seven strains and the optimum growth temperature was 32 degrees C. Bacillus thuringiensis could utilize acrylic acid for growth, when the initial acrylic acid concentration was below 1,690.4 mg/l. Besides this, when the initial acrylic acid concentration was below 606.8 mg/l, the acrylic acid removal efficiency exceeded 96.3%. Bacillus thuringiensis could tolerate 295.7 mg/l acrylamide and 198.4 mg/l acrylonitrile toxicity but could not tolerate 297.3 mg/l epsilon-caprolactam. PMID:16749456

Wang, C C; Lee, C M

2006-01-01

87

Removal of resin acids and sterols from pulp mill effluents by activated sludge treatment.  

PubMed

The wastewater treatment plant of an elemental chlorine free bleaching kraft pulp mill located in eastern Finland was sampled in order to study the fate of wood extractives and the toxicity to luminescence bacteria (Vibrio fischeri) in different parts of the plant. Resin acids and sterols were analyzed from water, particles and sludge samples during three different runs. Waters before biotreatment and primary sludge were found to be toxic; but in the activated sludge treatment toxicity was removed. During wastewater treatment, concentrations of wood extractives were reduced over 97%. In activated sludge treatment, over 94% of the resin acids and over 41% of the sterols were degraded or transformed to other compounds. Furthermore, in general, less than 5% of the resin acids and over 31% of the sterols were removed in biosludge to the sludge thickener. Most of the extractives were discharged attached to particles. Although some disturbing factors increased the load of wood extractives during samplings, these factors did not affect the operational efficiency of the secondary treatment system. PMID:12767285

Kostamo, A; Kukkonen, J V K

2003-07-01

88

Screening analyses of pinosylvin stilbenes, resin acids and lignans in Norwegian conifers.  

PubMed

The content and distribution of stilbenes and resin acids in Scots pine (Pinus sylvestris) and spruce (Picea abies), sampled in central Norway, have been examined. The contents of pinosylvin stilbenes in pine heartwood/living knots were 0.2-2/2-8 %(w/w). No stilbenes could be detected in spruce (Picea abies). The resin acid contents of pine sapwood/heartwood and knots were 1-4 and 5-10 % (w/w), respectively. Minor amounts of resin acids (<0.2/<0.04 %w/w) were identified in spruce wood/knots. The lignan content in knots of Norwegian spruce was 6.5 % (w/w). Diastereomerically pure hydroxymatairesinol (HMR, 84 % of total lignans) was readily isolated from this source since only minor quantities (2.6 % of total lignans) of the allo-HMR diastereomer was detected. Insignificant amounts of lignans were present in the sapwood. Lignans could not be detected in the sapwood or knots of Norwegian sallow (Salix caprea), birch(Betula pendula) or juniper (Juniperus communis). PMID:17962750

Hovelstad, Hanne; Leirset, Ingebjorg; Oyaas, Karin; Fiksdahl, Anne

2006-01-01

89

The isolation of omega-3 polyunsaturated fatty acids and methyl esters of fish oils by silver resin chromatography  

Microsoft Academic Search

Multigram quantities of the highly unsaturated ?3 component from samples of fish oil fatty acids and esters were isolated\\u000a by silver resin chromatography. An XN1010 resin column saturated with silver ions was utilized. Polyunsaturated fatty acid\\u000a (PUFA) esters from fish oil concentrate (FOC) were fractionated based on the number of double bonds by using solvent programming\\u000a (acetonitrile in methanol). Larger

R. O. Adlof; E. A. Emken

1985-01-01

90

Effect of acid and laser etching on shear bond strength of conventional and resin-modified glass-ionomer cements to composite resin.  

PubMed

Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-?m-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm(2). Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20. PMID:21234634

Navimipour, Elmira Jafari; Oskoee, Siavash Savadi; Oskoee, Parnian Alizadeh; Bahari, Mahmoud; Rikhtegaran, Sahand; Ghojazadeh, Morteza

2012-03-01

91

Simultaneous ion-exclusion\\/cation-exchange chromatography of anions and cations in acid rain waters on a weakly acidic cation-exchange resin by elution with sulfosalicylic acid  

Microsoft Academic Search

A simple, selective, and sensitive method for the simultaneous determination of anions (sulfate, nitrate, and chloride) and cations (sodium, ammonium, potassium, magnesium, and calcium) in acid rain waters was developed using ion-exclusion\\/cation-exchange chromatography with conductimetric detection. A weakly acidic cation-exchange resin column (Tosho TSKgel OA-PAK-A) and a sulfosalicylic acid–methanol–water eluent was used. With a mobile phase comprising 1.25 mM sulfosalicylic

Kazuhiko Tanaka; Kazutoku Ohta; Paul R Haddad; James S Fritz; Akiyoshi Miyanaga; Wenzhi Hu; Kiyoshi Hasebe

2000-01-01

92

Shear bond strength of resin cement to an acid etched and a laser irradiated ceramic surface  

PubMed Central

PURPOSE To evaluate the effects of hydrofluoric acid etching and Er,Cr:YSGG laser irradiation on the shear bond strength of resin cement to lithium disilicate ceramic. MATERIALS AND METHODS Fifty-five ceramic blocks (5 mm × 5 mm × 2 mm) were fabricated and embedded in acrylic resin. Their surfaces were finished with 1000-grit silicon carbide paper. The blocks were assigned to five groups: 1) 9.5% hydrofluoric-acid etching for 60 s; 2-4), 1.5-, 2.5-, and 6-W Er,Cr:YSGG laser applications for 60 seconds, respectively; and 5) no treatment (control). One specimen from each group was examined using scanning electron microscopy. Ceramic primer (Rely X ceramic primer) and adhesive (Adper Single Bond) were applied to the ceramic surfaces, followed by resin cement to bond the composite cylinders, and light curing. Bonded specimens were stored in distilled water at 37? for 24 hours. Shear bond strengths were determined by a universal testing machine at 1 mm/min crosshead speed. Data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests (?=0.05). RESULTS Adhesion was significantly stronger in Group 2 (3.88 ± 1.94 MPa) and Group 3 (3.65 ± 1.87 MPa) than in Control group (1.95 ± 1.06 MPa), in which bonding values were lowest (P<.01). No significant difference was observed between Group 4 (3.59 ± 1.19 MPa) and Control group. Shear bond strength was highest in Group 1 (8.42 ± 1.86 MPa; P<.01). CONCLUSION Er,Cr:YSGG laser irradiation at 1.5 and 2.5 W increased shear bond strengths between ceramic and resin cement compared with untreated ceramic surfaces. Irradiation at 6 W may not be an efficient ceramic surface treatment technique.

Motro, Pelin Fatma Karagoz; Yurdaguven, Haktan

2013-01-01

93

Phosphoric acid esters cannot replace polyvinylphosphonic acid as phosphoprotein analogs in biomimetic remineralization of resin-bonded dentin  

PubMed Central

Polyvinylphosphonic acid (PVPA), a biomimetic analog of phosphoproteins, is crucial for recruiting polyacrylic acid (PAA)-stabilized amorphous calcium phosphate nanoprecursors during biomimetic remineralization of dentin collagen matrices. This study tested the null hypothesis that phosphoric acid esters of methacrylates in dentin adhesives cannot replace PVPA during bimimetic remineralization of resin-dentin interfaces. Human dentin specimens were bonded with: I) XP Bond, an etch-and-rinse adhesive using moist bonding; II) XP Bond using dry bonding; and III) Adper Prompt L-Pop, a self-etching adhesive. The control medium contained only set Portland cement and a simulated body fluid (SBF) without any biomimetic analog. Two experimental Portland cement/SBF remineralization media were evaluated: the first contained PAA as the sole biomimetic analog, the second contained PAA and PVPA as dual biomimetic analogs. No remineralization of the resin-dentin interfaces could be identified from specimens immersed in the control medium. After 2–4 months in the first experimental medium, specimens exhibited either no remineralization or large crystal formation within hybrid layers. Only specimens immersed in the second remineralization medium produced nanocrystals that accounted for intrafibrillar remineralization within hybrid layers. The null hypothesis could not be rejected; phosphoric acid esters in dentin adhesives cannot replace PVPA during biomimetic remineralization of adhesive-bonded dentin.

Mai, Sui; Kim, Young Kyung; Toledano, Manuel; Breschi, Lorenzo; Ling, Jun Qi; Pashley, David H.; Tay, Franklin R.

2009-01-01

94

Exposure to dust, resin acids, and monoterpenes in softwood lumber mills.  

PubMed

A study to assess exposure to potential respiratory hazards in a large lumber mill processing spruce (Picea engelmannii and glauca), pine (Pinus contorta), and fir (Abies lasiocarpa) used a random sampling strategy to assess exposures for all jobs in the sawmill, planer mills, and yard. Personal samples for inhalable particulate were collected to measure exposure to dust and resin acids (abietic acid and pimaric acid). To estimate wood dust exposure, rather than overall dust, the resin acid content within dust was used in combination with observations of job tasks and proximity to dust sources. Passive dosimeters were used to measure exposure to alpha-pinene, beta-pinene, delta3-carene, and other unidentified wood volatiles suspected to be monoterpenes. The GM of the 220 inhalable particulate samples was 1.0 mg/m3 whereas the mean abietic acid, pimaric acid, and estimated wood dust levels were 7.2 microg/m3, 0.6 microg/m3, and 0.5 mg/m3, respectively. The GMs of the 222 monoterpene samples were 0.1 mg/m3 for alpha-pinene, 0.3 mg/m3 for beta-pinene, 0.1 mg/m3 for delta3-carene, and 0.5 mg/m3 for the unidentified wood volatiles. Monoterpene exposures were much lower than those observed in other studies conducted in Sweden and Finland. The results of this exposure assessment highlight the importance of considering the content of airborne particulates in lumber mills as well as potential exposure to wood chemicals. PMID:10976682

Demers, P A; Teschke, K; Davies, H W; Kennedy, S M; Leung, V

2000-01-01

95

Cleavage of protected amino acids and peptides from benzyl ester resins by transesterification with potassium cyanide in benzyl alcohol.  

PubMed

The nature of the protected amino acid or peptide attached to the Merrifield resin influences the rate of KCN-catalyzed transesterification in benzyl alcohol. Although crown ether complexes of KCN do not expedite the reaction, sterically hindered amino acids are readily transesterified in the presence of saturating concentrations of KCN at elevated temperatures. PMID:7459690

Moore, G J; Kwok, Y C

1980-08-01

96

ANION EXCHANGE RESIN SEPARATION OF THE RARE EARTHS, YTTRIUM, AND SCANDIUM IN NITRIC ACID-METHANOL MIXTURES  

Microsoft Academic Search

The adsorption of the rare earths, yttrium, and scandium from nitric ; acid--methanol solutions was studied using strongly basic anion exchange resins. ; Adsorption measurements were made at room temperature using the column elution ; technique and employing emission spectrographic analysis. Distribution ; coefficients were a function of both the volume percentage of alcohol and of the ; nitric acid

J. P. Faris; J. W. Warton

1962-01-01

97

Self-assembly of resins and asphaltenes facilitates asphaltene dissolution by an organic acid.  

PubMed

Asphaltene precipitation occurs in petroleum fluids under certain unfavorable conditions, but can be controlled by tuning composition. Aromatic solvents in large quantities can prevent precipitation entirely and can dissolve already precipitated asphaltenes. Some polymeric surfactants can dissolve asphaltenes when added at much lower concentrations than required by aromatic solvents. Other dispersants can truncate asphaltene precipitation at the sub-micron length scale, creating stable colloidal asphaltene dispersants. One particular asphaltene dispersant, dodecylbenzene sulfonic acid (DBSA), can do both, namely: (1) stabilize asphaltene colloids and (2) dissolve asphaltenes to the molecular scale. Acid-base interactions are responsible for the efficiency of DBSA in dissolving asphaltenes compared to aromatic solvents. However, many details remain to be quantified regarding the action of DBSA on asphaltenes, including the effect of petroleum fluid composition. For instance, resins, naturally amphiphilic components of petroleum fluids, can associate with asphaltenes, but it is unknown whether they cooperate or compete with DBSA. Similarly, the presence of metals is known to hinder asphaltene dissolution by DBSA, but its effect on colloidal asphaltene stabilization has yet to be considered. We introduce the concepts of cooperativity and competition between petroleum fluid components and DBSA in stabilizing and dissolving asphaltenes. Notably, we find that resins cooperatively interact with DBSA in dissolving asphaltenes. We use UV-vis spectroscopy to investigate the interactions responsible for the phase transitions between unstable suspensions, stable suspensions, and molecular solutions of asphaltenes. PMID:23351475

Hashmi, Sara M; Firoozabadi, Abbas

2013-03-15

98

Iminodiacetic acid functionalized cation exchange resin for adsorptive removal of Cr(VI), Cd(II), Ni(II) and Pb(II) from their aqueous solutions  

Microsoft Academic Search

Iminodiacetic acid functionality has been introduced on styrene–divinyl benzene co-polymeric beads and characterized by FT-IR in order to develop weak acid based cation exchange resin. This resin was evaluated for the removal of different heavy metal ions namely Cd(II), Cr(VI), Ni(II) and Pb(II) from their aqueous solutions. The results showed greater affinity of resin towards Cr(VI) for which 99.7% removal

R. K. Misra; S. K. Jain; P. K. Khatri

2011-01-01

99

Affinity purification of the voltage-sensitive sodium channel from electroplax with resins selective for sialic acid  

SciTech Connect

The voltage-sensitive sodium channel present in the eel (Electrophorus electricus) has an unusually high content of sialic acid, including {alpha}-(2{yields}8)-linked polysialic acid, not found in other electroplax membrane glycopeptides. Lectins from Limax flavus (LFA) and wheat germ (WGA) proved the most effective of 11 lectin resins tried. The most selective resin was prepared from IgM antibodies against Neisseria meningitidis {alpha}-(2{yields}8)-polysialic acid which were affinity purified and coupled to Sepharose 4B. The sodium channel was found to bind to WGA, LFA, and IgM resins and was readily eluted with the appropriate soluble carbohydrates. Experiments with LFA and IgM resins demonstrated binding and unbinding rates and displacement kinetics, which suggest highly specific binding at multiple sites on the sodium channel protein. In preparative-scale purification of protein previously fractionated by anion-exchange chromatography, without stabilizing TTX, high yields were reproducibly obtained. Further, when detergent extracts were prepared from electroplax membranes fractionated by low-speed sedimentation, a single step over the IgM resin provided a 70-fold purification, yielding specific activities of 3,200 pmol of ({sup 3}H)TTX-binding sites/mg of protein and a single polypeptide of {approximately}285,000 Da on SDS-acrylamide gels. No small peptides were observed after this 5-h isolation. The authors describe a cation-dependent stabilization with millimolar levels of monovalent and micromolar levels of divalent species.

James, W.M.; Emerick, M.C.; Agnew, W.S. (Yale Univ. School of medicine, New Haven, CT (USA))

1989-07-11

100

Influence of Functional Sulfonic Acid Group on Pyrolysis Characteristics for Cation Exchange Resin  

Microsoft Academic Search

Pyrolysis of spent ion exchange resins is used to reduce radioactive waste volume and to make the final waste form more stable. The weight loss of cation exchange resin after pyrolysis is only 50w\\/o, while that of anion exchange resin is 90w\\/o. Fundamental experiments were performed to investigate the reason for the small weight loss of the former.The cation resin

Masami MATSUDA; Kiyomi FUNABASHI; Hideo YUSA; Makoto KIKUCHI

1987-01-01

101

Characterization of Negative Tone Photoresist Based on Acid Catalyzed Dehydration Crosslinking of Novolac Resins Having Pendant Carboxyl Groups  

Microsoft Academic Search

Esterification of 4-hydroxyphenylacetic acid with various alcohols of (+)-borneol, (±)-borneol and ethylene glycol monobutyl ether were carried out. The ester compounds were then copolymerized with various comonomers of bisphenol-A, phenol and formaldehyde. Physical properties and molecular structures of such synthesized phenolic resins were investigated by using IR, NMR, DSC, and TGA. To introduce carboxyl groups onto the side chain of

Hui-Hsiang Liu; Wei-Tin Chen; Fuh-Tsang Wu

2002-01-01

102

Recovery of nickel and cobalt from organic acid complexes: adsorption mechanisms of metal-organic complexes onto aminophosphonate chelating resin.  

PubMed

This study examined the recovery of nickel and cobalt from organic acid complexes using a chelating aminophosphonate Purolite S950 resin. These metal complexes are generated by bioleaching nickel laterite ores, a commercial nickel and cobalt mineral oxide, with heterotrophic organism and their metabolites or organic acid products. Equilibrium adsorption tests were conducted as a function of Ni and Co concentrations (15-2000 mg/L), solution pH (0.01 and 0.1 M acids) and three metabolic complexing agents (citrate, malate and lactate). It was shown that the adsorption of the various Ni- and Co-complexes on Purolite were quite low, 16-18 and 5.4-9 mg/g of resin, respectively, in comparison to the smaller nickel ions and nickel sulfate. This was attributed to the bulky organic ligands which promoted crowding effect or steric hindrance. The adsorption of these complexes was further hampered by the strong affinity of the resin to H+ ions under acidic conditions. Mechanisms of adsorption, as inferred from the fitted empirical Langmuir and Freundlich models, were correlated to the proposed steric hindrance and competitive adsorption effects. Nickel and cobalt elution from the resin were found be effective and were independent of the type of metal complexes and metal concentrations. This study demonstrated the relative challenges involved in recovering nickel and cobalt from bioleaching solutions. PMID:16698178

Deepatana, A; Valix, M

2006-09-21

103

Determinants of Exposure to Inhalable Particulate, Wood Dust, Resin Acids, and Monoterpenes in a Lumber Mill Environment  

Microsoft Academic Search

In a lumber mill in the northern inland region of British Columbia, Canada, we measured inhalable particulate, resin acid, and monoterpene exposures, and estimated wood dust exposures. Potential determinants of exposure were documented concurrently, including weather conditions, tree species, wood conditions, jobs, tasks, equipment used, and certain control measures. Over 220 personal samples were taken for each contaminant. Geometric mean

KAY TESCHKE; PAUL A. DEMERS; HUGH W. DAVIES; SUSAN M. KENNEDY; STEPHEN A. MARION; VICTOR LEUNG

1999-01-01

104

Influence of hydrofluoric acid on extraction of thorium using a commercially available extraction chromatographic resin.  

PubMed

The dependence of Th recovery on hydrofluoric acid (HF) concentration in nitric acid (HNO(3)) solutions (1-5 mol/dm(3)) containing 1x10(-6) mol/dm(3) of Th and various concentrations of HF and the elution behavior were studied using a commercially available UTEVA (for uranium and tetravalent actinide) resin column. Thorium recovery decreased with an increase in HF concentration in the sample solutions. The concentration of HF at which Th recovery started to decrease was approximately 1x10(-4) mol/dm(3) in 1 mol/dm(3) HNO(3) solution, approximately 1x10(-3) mol/dm(3) in 3 mol/dm(3) HNO(3) solution, and approximately 1x10(-2) mol/dm(3) in 5 mol/dm(3) HNO(3) solution. When Al(NO(3))(3) (0.2 mol/dm(3)) or Fe(NO(3))(3) (0.6 mol/dm(3)) was added as a masking agent for F(-) to the Th solution containing 1x10(-1) mol/dm(3) HF and 1 mol/dm(3) HNO(3), Th recovery improved from 1.4+/-0.3% to 95+/-5% or 93+/-3%. Effective extraction of Th using UTEVA resin was achieved by selecting the concentration of HNO(3) and/or adding masking agents such as Al(NO(3))(3) according to the concentration of HF in the sample solution. PMID:19327779

Shimada-Fujiwara, Asako; Hoshi, Akiko; Kameo, Yutaka; Nakashima, Mikio

2009-05-01

105

Vacancy ion-exclusion chromatography of haloacetic acids on a weakly acidic cation-exchange resin  

Microsoft Academic Search

A new and simple approach is described for the determination of the haloacetic acids (such as mono-, di- and trichloroacetic acids) usually found in drinking water as chlorination by-products after disinfection processes and acetic acid. The new approach, termed vacancy ion-exclusion chromatography, is based on an ion-exclusion mechanism but using the sample solution as the mobile phase, pure water as

Murad I. H. Helaleh; Kazuhiko Tanaka; Masanobu Mori; Qun Xu; Hiroshi Taoda; Ming-Yu Ding; Wenzhi Hu; Kiyoshi Hasebe; Paul R. Haddad

2003-01-01

106

Use of Sulfonated Cation-Exchange Resin Based on Hypercrosslinked Polystyrene for the Separation of Organic Acids  

Microsoft Academic Search

The use of sulfonated cation-exchange resins based on hypercrosslinked polystyrene (HCPS) and highly cross-linked polystyrene–divinylbenzene (80% divinylbenzene) for the separation of organic acids was studied. The influence of the concentration of the eluent, temperature of the chromatographic column, and concentration of acetonitrile in the eluent on the retention of aliphatic carboxylic acids in ion-exclusion chromatography was examined. The optimal separation

P. N. Nesterenko; P. A. Kebets; Yu. V. Volgin

2001-01-01

107

Hydrogenation of unsaturated carboxylic acids on functional gel-type resin supported Pd catalysts: The effect of reactant structure  

Microsoft Academic Search

Functional gel-type resin-based palladium catalysts (0.5–2wt.% Pd) of well dispersed Pd nanoparticles were prepared and characterized by SEM, TEM techniques and swelling measurements. The role of specific properties of gel-type matrix was studied in the hydrogenation of unsaturated CC bonds in series of carboxylic acids, derivatives of acrylic acid. They differ in the type of substituents (methyl, phenyl and carboxyl

A. Knapik; A. Drelinkiewicz; M. Szaleniec; W. Makowski; A. Waksmundzka-Góra; A. Bukowska; W. Bukowski; J. Noworól

2008-01-01

108

Separation of americium and curium by use of tertiary pyridine resin in nitric acid\\/methanol mixed solvent system  

Microsoft Academic Search

The separation of Am and Cm by using the tertiary pyridine resin embedded in silica beads was studied in nitric acid\\/methanol\\u000a mixed solvent system. This separation system of Am and Cm is very simple and easy. The adsorption and separation behaviors\\u000a of Am and Cm were investigated with changing the nitric acid and the methanol concentrations. It was confirmed that

T. Suzuki; K. Otake; M. Sato; A. Ikeda; M. Aida; Y. Fujii; M. Hara; T. Mitsugashira; M. Ozawa

2007-01-01

109

High-performance ion-exclusion\\/cation-exchange chromatography of anions and cations in acid rain waters on a weakly acidic cation-exchange resin  

Microsoft Academic Search

A new method for the simultaneous determination of anions (sulfate, nitrate, and chloride) and cations (sodium, ammonium, potassium, magnesium, and calcium) in acid rain waters was investigated using high-performance ion-exclusion\\/cation-exchange chromatography with conductimetric detection on a separation column packed with a polymethacrylate-based weakly acidic cation-exchange resin in the hydrogen-form and an eluent comprising 1.5 mM sulfosalicylic acid–6 mM 18-crown-6 at

Kazuhiko Tanaka; Kazutoku Ohta; Paul R Haddad; James S Fritz; Akiyashi Miyanaga; Wenzhi Hu; Kiyashi Hasebe; Kwang-Pill Lee; Corrado Sarzanini

2001-01-01

110

Two new glycosidic acids, multifidinic acids F and G, of the ether-insoluble resin glycoside (convolvulin) from the seeds of Quamoclit × multifida.  

PubMed

Two new glycosidic acids, multifidinic acids F and G, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit × multifida (syn. Q. sloteri House, Convolvulaceae), a hybrid between Q. pennata and Q. coccinea. The two compounds are the third and fourth examples of bisdesmosides of glycosidic acids having sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at C-11. PMID:23271665

Ono, Masateru; Akiyama, Kousuke; Kishida, Makiko; Okawa, Masafumi; Kinjo, Junei; Yoshimitsu, Hitoshi; Miyahara, Kazumoto

2013-10-01

111

Heating and microwave assisted SPPS of C-terminal acid peptides on trityl resin: the truth behind the yield.  

PubMed

Despite correct purity of crude peptides prepared on trityl resin by Fmoc/tBu microwave assisted solid phase peptide synthesis, surprisingly, lower yields than those expected were obtained while preparing C-terminal acid peptides. This could be explained by cyclization/cleavage through diketopiperazine formation during the second amino acid deprotection and third amino acid coupling. However, we provide here evidence that this is not the case and that this yield loss was due to high temperature promoted hydrolysis of the 2-chlorotrityl ester, yielding premature cleavage of the C-terminal acid peptides. PMID:24142338

Echalier, Cécile; Al-Halifa, Soultan; Kreiter, Aude; Enjalbal, Christine; Sanchez, Pierre; Ronga, Luisa; Puget, Karine; Verdié, Pascal; Amblard, Muriel; Martinez, Jean; Subra, Gilles

2013-12-01

112

Rapid removal of copper with magnetic poly-acrylic weak acid resin: Quantitative role of bead radius on ion exchange.  

PubMed

A novel magnetic weak acid resin NDMC was self-synthesized for the removal of Cu(2+) from aqueous solutions. NDMC showed superior properties on the removal of Cu(2+) compared to commercial resins C106 and IRC-748, which was deeply investigated by adsorption isotherms and kinetic tests. The equilibrium adsorption amount of Cu(2+) onto NDMC (267.2mg/g) was almost twice as large as that onto IRC-748 (120.0mg/g). The adsorption kinetics of Cu(2+) onto the three resins fitted well with the pseudo-second-order equation. The initial adsorption rate h of NDMC was about 4 times that of C106 and nearly 8 times that of IRC-748 at the initial concentration of 500mg/L. External surface area was determined to be the key factor in rate-controlling by further analyzing the adsorption thermodynamics, kinetics parameters and physicochemical properties of the resins. NDMC resin with the smallest bead radius possessed the largest external surface and therefore exhibited the fastest kinetics. The adsorption amount of Cu(2+) onto NDMC was not influenced as the concentration of Na(+) increased from 1.0 to 10.0mM/L. Dilute HCl solution could effectively desorb Cu(2+). NDMC demonstrated high stability during 10 adsorption/desorption cycles, showing great potential in the rapid removal of Cu(2+) from wastewater. PMID:24681592

Fu, Lichun; Shuang, Chendong; Liu, Fuqiang; Li, Aimin; Li, Yan; Zhou, Yang; Song, Haiou

2014-05-15

113

Efficacy of self-etching primers containing carboxylic acid monomers on the adhesion between composite resin and dentin.  

PubMed

A study was conducted to examine the efficacy of carboxylic acid monomers as self-etching primers by measuring the tensile bond strengths between composite resin and dentin. Several kinds of carboxylic acid monomers, such as o-(N-methacryloyl amino)benzoic acid (o-MABA), m-(N-methacryloyl amino)benzoic acid (m-MABA), p-(N-methacryloyl amino)benzoic acid (p-MABA), 4-methacryloxy phthalic acid (4-MPA), 2-(N-methacryloyl amino) terephthalic acid (2-MATPA), and 5-(N-methacryloyl) amino)isophthalic acid (5-MAIPA), were prepared. 4-methacryloxyethyl trimellitic anhydride (4-META) was also used as a component of the self-etching primer. The DMSO solutions of these monomers were used as self-etching primers. The tensile bond strengths between composite resin and dentin were measured after 24 h immersion in water at 37 degrees C. When DMSO was used as a self-etching primer, the bond strengths were below 5 MPa. Among the monocarboxylic acid monomers, m-MABA gave the highest mean bond strength at 60 s application, and 5MAIPA gave the highest mean bond strength at 30 s application among the dicarboxylic acid monomers, although the differences among the values were not always significant. The smear layer was partially dissolved by treatment with the self-etching primer. PMID:9663978

Hayakawa, T; Kikutake, K; Nemoto, K

1998-03-01

114

Bile Acid Binding Resin Improves Metabolic Control through the Induction of Energy Expenditure  

PubMed Central

Background Besides well-established roles of bile acids (BA) in dietary lipid absorption and cholesterol homeostasis, it has recently become clear that BA is also a biological signaling molecule. We have shown that strategies aimed at activating TGR5 by increasing the BA pool size with BA administration may constitute a significant therapeutic advance to combat the metabolic syndrome and suggest that such strategies are worth testing in a clinical setting. Bile acid binding resin (BABR) is known not only to reduce serum cholesterol levels but also to improve glucose tolerance and insulin resistance in animal models and humans. However, the mechanisms by which BABR affects glucose homeostasis have not been established. We investigated how BABR affects glycemic control in diet-induced obesity models. Methods and Findings We evaluated the metabolic effect of BABR by administrating colestimide to animal models for the metabolic syndrome. Administration of BABR increased energy expenditure, translating into significant weight reduction and insulin sensitization. The metabolic effects of BABR coincide with activation of cholesterol and BA synthesis in liver and thermogenesis in brown adipose tissue. Interestingly, these effects of BABR occur despite normal food intake and triglyceride absorption. Administration of BABR and BA had similar effects on BA composition and thermogenesis, suggesting that they both are mediated via TGR5 activation. Conclusion Our data hence suggest that BABR could be useful for the management of the impaired glucose tolerance of the metabolic syndrome, since they not only lower cholesterol levels, but also reduce obesity and improve insulin resistance.

Watanabe, Mitsuhiro; Morimoto, Kohkichi; Houten, Sander M.; Kaneko-Iwasaki, Nao; Sugizaki, Taichi; Horai, Yasushi; Mataki, Chikage; Sato, Hiroyuki; Murahashi, Karin; Arita, Eri; Schoonjans, Kristina; Suzuki, Tatsuya; Itoh, Hiroshi; Auwerx, Johan

2012-01-01

115

Hypercrosslinked strong anion-exchange resin for extraction of acidic pharmaceuticals from environmental water.  

PubMed

Two novel high-specific surface area polymeric sorbents (HXLPP-SAXa and HXLPP-SAXb) were synthesised and evaluated as solid-phase extraction sorbents. The novel sorbents under study are based on hypercrosslinked polymer microspheres and designed specifically to offer ion-exchange properties; the specific polymers of interest in the current work have been chemically modified in such a way as to impart a tuneable level of strong anion-exchange character onto the sorbents. The novel sorbents were applied as strong anion-exchange sorbents in solid-phase extraction studies, with the goal being to selectively extract a group of acidic compounds from complex environmental samples in an efficient manner. Out of two HXLPP-SAX resins evaluated in this study, it was found that the sorbent with the lower ion-exchange capacity (HXLPP-SAXa) gave rise to the best overall performance characteristics and, indeed, was found to compare favourably to the solid-phase extraction performance of commercial strong anion-exchange sorbents. When the HXLPP-SAXa sorbent was applied to the solid-phase extraction of environmental water samples, the result showed quantitative and selective extraction of low levels of acidic pharmaceuticals from 500 mL of river water and 100 mL of effluent wastewater. PMID:22907847

Bratkowska, Dominika; Davies, Arlene; Fontanals, Núria; Cormack, Peter A G; Borrull, Francesc; Sherrington, David C; Marcé, Rosa M

2012-10-01

116

RECOVERY OF URANIUM FROM AN ACID LEACH LIQUOR, USING AN ANION EXCHANGE RESIN AND SODIUM CARBONATE AND BICARBONATE AS ELUTING AGENTS  

Microsoft Academic Search

It has been shown that it is possible, using both sodium carbonate ; solution and sodium bicarbonate solution as eluting agents, to remove uranium ; completely from Amberlite IRA-400 anion exchange resin loaded from an acid leach ; liquor. During 51 cycles of loading and elution, the resin sample used showed ; only slight deterioration. The uranium was precipitated from

E. Kornelsen; V. M. McNamara; J. C. Ingles

1959-01-01

117

Degradation of salicylic acid by photo-assisted Fenton reaction using Fe ions on strongly acidic ion exchange resin as catalyst  

Microsoft Academic Search

The photo-assisted Fenton degradation of salicylic acid (SA) was studied by using strongly acidic ion exchange resin (SAIER) exchanged with Fe ions as catalyst in the presence of UV light (254nm) and H2O2. The X-ray photoelectron spectroscopy (XPS) results revealed that the Fe ions are indeed anchored by the sulfonate groups on the surface of the SAIER and are Fe3+.

Jiyun Feng; Xijun Hu; Po Lock Yue

2004-01-01

118

Effects of niacin combination therapy with statin or bile Acid resin on lipoproteins and cardiovascular disease.  

PubMed

Two large studies in populations selected for cardiovascular disease (CVD) demonstrated that raising high-density lipoprotein (HDL) cholesterol with niacin added to statin therapy did not decrease CVD. We examine the association of lipoprotein subfractions with niacin and changes in coronary stenosis and CVD event risk. One hundred and seven patients from 2 previous studies using niacin in combination with either statin or bile acid-binding resin were selected to evaluate changes in lipoproteins separated by density-gradient ultracentrifugation to progression of coronary artery disease as assessed by quantitative coronary angiography. Improvement in coronary stenosis was significantly associated with the decrease of cholesterol in the dense low-density lipoprotein (LDL) particles and across most of the intermediate density lipoprotein (IDL) and very low density lipoprotein particle density range, but, not with any of the HDL fraction or of the more buoyant LDL fractions. Event-free survival was significantly associated with the decrease of cholesterol in the dense LDL and IDL; there was no association with changes in cholesterol in the HDL and buoyant LDL fractions. Niacin combination therapy raises HDL cholesterol and decreases dense LDL and IDL cholesterol levels. Changes in LDL and IDL are related to improvement in CVD. Lipoprotein subfraction analysis should be performed in larger studies utilizing niacin in combination with statins. PMID:24641964

Zambon, Alberto; Zhao, Xue-Qiao; Brown, B Greg; Brunzell, John D

2014-05-01

119

Protic acid resin enhanced 1-butyl-3-methylimidazolium chloride pretreatment of Arundo donax Linn.  

PubMed

To improve the cellulose digestibility of energy crop Arudo donax Linn. with cost-efficient, a novel pretreatment of protic acid resin Amberlyst 35DRY catalyzed inexpensive ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) was developed in this work. The pretreatment was performed at 160°C with [C4mim]Cl for 1.5h, followed by Amberlyst 35DRY catalyzed at 90°C for 1h. The IL-Amberlyst pretreatment was demonstrated to be effective, evidenced by the reduction in cellulose crystallinity (31.4%) and increased porosity caused by extensive swelling the undissolved biomass and partial depolymerization of the longer cellulose chain of the dissolved biomass by Amberlyst. Consequently, a higher glucose yield (92.8%) was obtained than for the single [C4mim]Cl pretreatment (42.8%) at an enzyme loading of 20FPU/g substrate. Overall, the enhanced pretreatment was competitive by using inexpensive and recyclable IL-Amberlyst 35DRY pretreated system with shorter processing time and reduced enzyme usage. PMID:25001325

You, Tingting; Zhang, Liming; Zhou, Sukun; Xu, Feng

2014-09-01

120

Gas chromatographic determination of organic acids from fruit juices by combined resin mediated methylation and extraction in supercritical carbon dioxide.  

PubMed

A procedure in which anionic analytes, trapped on ion exchange resin, are simultaneously methylated and released using methyl iodide in either supercritical carbon dioxide or acetonitrile has been extended to polyfunctional organic acids. The combined SFE methylation of fruit juice acids trapped onto ion exchange resin proceeds in good yield producing the methyl esters of fumaric, succinic, malic, tartaric, isocitric and citric acids which are readily separated by GC. Using this procedure low concentrations of one acid can be detected and quantitated in the presence of very high concentrations of another. This new method detects tartaric acid at levels of 10 ppm in juices containing 10,000 ppm citric acid. Quantitation was performed either by using GC-FID with triethyl citrate or diethyl tartrate as internal standards or with the element specific calibration capability of the GC-AED. A simple new technique for the determination of citric/isocitric acid ratio is now available. Also, in contrast to HPLC methods, the identity of an analyte is readily confirmed by GC-MS. PMID:9409006

Barden, T J; Croft, M Y; Murby, E J; Wells, R J

1997-10-17

121

Effect of ascorbic acid on bond strength between the hydrogen peroxide-treated fiber posts and composite resin cores  

PubMed Central

Aim: This study evaluated the effect of 10% ascorbic acid on the bond strength between fiber post and composite resin core after applying 24% hydrogen peroxide. Materials and Methods: Twenty-four hydrogen peroxide-treated fiber posts were divided into 4 groups (n = 6). Group 1 was the control group with no treatment. In groups 2-4, post surfaces were treated with 10% v ascorbic acid solution for 10, 30 and 60 minutes, respectively. Cores were built up using flowable composite resin. Two sticks were prepared from each specimen. Microtensile bond strength test was performed for each stick. Failure modes of sticks were evaluated under a stereomicroscope (×20). Surface morphologies of two fractured sticks from each group were assessed by SEM. Statistical analysis: Data were analyzed using one-way ANOVA and Tukey HSD tests (? = 0.05). Results: The highest microtensile bond strength was observed in Group 4 (20.55 ± 2.09) and the lowest in Group 1 (10.10 ± 0.55). There were significant differences in microtensile bond strength between all the groups (P < 0.05). Conclusion: It is concluded that ascorbic acid application increased the microtensile bond strength between the hydrogen peroxide treated fiber post and composite resin core. The increase is dependent on the duration of exposure to the antioxidant.

Talebian, Reza; Khamverdi, Zahra; Nouri, Maryam; Kasraei, Shahin

2014-01-01

122

Solid-phase synthesis with attachment of peptide to resin through an amino acid side chain: (8-lysine)-vasopressin.  

PubMed

It is proposed that the scope of solid-phase peptide synthesis could be considerably broadened by attaching peptides to the solid-phase through functional side-chain groups rather than through the commonly used alpha-carboxyl groups. Side-chain attachment offers the use of a large variety of chemical linkages to solid supports. Attachment through the epsilon-amino group of the lysine residue to a polystyrene resin has been applied to a solid-phase synthesis of lysine-vasopressin. N(alpha)-tert-butyl-oxycarbonyl-L-lysyl-glycinamide was condensed with chloroformoxymethyl polystyrene-2% divinylbenzene resin. After removal of the N(alpha)-protecting tert-butyloxycarbonyl group, the peptide chain was elongated by standard Merrifield procedures to give Tos-Cys(Bzl)-Tyr-Phe-Glu-(NH(2)) - Asp(NH(2)) - Cys(Bzl) - Pro - Lys(Z - resin) - Gly-NH(2). Cleavage from the resin with HBr in dioxane or trifluoroacetic acid gave a partially protected nonapeptide hydrobromide. For purification, it was converted into a fully protected peptide by treatment with benzyl p-nitro-phenyl carbonate and crystallized. Deprotection by sodium in liquid ammonia, oxidative cyclization, IRC-50 desalting, and ion-exchange chromatography gave lysinevasopressin with high potency in a rat-pressor assay. PMID:5280519

Meienhofer, J; Trzeciak, A

1971-05-01

123

The effect of trimethyl, triethyl, tripropyl, and tributyl amine functional groups in strong-base anion exchange resin on the sorption of Pu(IV) from nitric acid  

SciTech Connect

Four macroporous, strong-base anion exchange resins of similar crosslinkage and porosity, which differed only in their trialkyl amine functional groups, were compared for sorbing PU(IV) from nitric acid. Resins with trimethyl, triethyl or tripropyl amine functional groups exhibited generally similar behavior over the range of 1 to 12 M nitric acid. The distribution coefficients of these three resins for PU(IV) peaked near 7 M nitric acid, as expected. However, the resin with a tributyl amine functional group sorbed PU(IV) only from >7 M nitric acid, in a pattern different from that seen with any other anion exchange resin. We believe this behavior indicates two independent sorption mechanisms for Pu(IV). For the first three resins, a hydrophilic Pu(HNO{sub 3}){sub 4}{center_dot}5H{sub 2} complex approaches the exchange site, where it is converted to HPu(NO{sub 3}){sub 6}{sup {minus}} during sorption. The other process, which has been observed only with the tributyl amine resin, may involve the direct sorption of a hydrophobic hexanitratoplutonate complex. This possibility is supported by absorption spectrophotometric data.

Marsh, S.F.

1992-12-01

124

Application of polymethacrylate resin as stationary phase in liquid chromatography with UV detection for C1-C7 aliphatic monocarboxylic acids and C1-C7 aliphatic monoamines.  

PubMed

The application of unfunctionized polymethacrylate resin (TSKgel G3000PWXL) as a stationary phase in liquid chromatography with UV detection for C1-C7 aliphatic monocarboxylic acids (formic acid, acetic acid, propionic acid, butyric acid, isovaleric acid, valeric acid, 3,3-dimethylbutyric acid, 4-methylvaleric acid, hexanoic acid, 2-methylhexanoic acid, 5-methylhexanoic acid and heptanoic acid) and C1-C7 aliphatic monoamines (methylamine, ethylamine, propylamine, isobutylamine, butylamine, isoamylamine, amylamine, 1,3-dimethylbutylamine, hexylamine, 2-heptylamine and heptylamine) was carried out. Using dilute sulfuric acid as the eluent, the TSKgel G3000PWXL, resin acted as an advanced stationary phase for these C1-C7 carboxylic acids. Excellent simultaneous separation and symmetrical peaks for these C1-C7 carboxylic acids were achieved on a TSKgel G3000PWXL column (150 mm x 6 mm i.d.) in 60 min with 0.25 mM sulfuric acid containing 1 mM 2-methylheptanoic acid at pH 3.3 as the eluent. Using dilute sodium hydroxide as the eluent, the TSKgel G3000PWXL resin also behaved as an advanced stationary phase for these C1-C7 amines. Excellent simultaneous separation and good peaks for these C1-C7 amines were achieved on the TSKgel G3000PWXL column in 60 min with 10 mM sodium hydroxide containing 0.5 mM 1-methylheptylamine at pH 11.9 as the eluent. PMID:15250419

Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi; Takeuchi, Toyohide

2004-06-11

125

Novel silica-based ion exchange resin.  

National Technical Information Service (NTIS)

Eichrom's highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchang...

1997-01-01

126

A green and efficient protocol for large-scale production of glycyrrhizic acid from licorice roots by combination of polyamide and macroporous resin adsorbent chromatography.  

PubMed

A green and efficient method for large-scale preparation of glycyrrhizic acid from licorice roots was developed by combination of polyamide and macroporous resin. The entire preparation procedure consisted of two simple separation steps. The first step is to use polyamide resin to remove licorice flavoniods from the licorice crude extract. Subsequently, various macroporous resins were tried to purify glycyrrhizic acid, and HPD-400 showed the most suitable adsorption and desorption properties. Under the optimized conditions, a large-scale preparation of glycyrrhizic acid from licorice roots was carried out. A 20 kg raw material produced 0.43 kg of glycyrrhizic acid using green aqueous ethanol as the solvent. The purity of glycyrrhizic acid was increased from 11.40 to 88.95% with a recovery of 76.53%. The proposed method may be also extended to produce large-scale other triterpenoid saponins from herbal materials. PMID:23355362

Zheng, Yun-Feng; Wei, Juan-Hua; Qi, Lian-Wen; Cheng, Jian-Ming; Peng, Guo-Ping

2013-02-01

127

Adsorption characteristics of rebaudioside A and stevioside on cross-linked poly(styrene-co-divinylbenzene) macroporous resins functionalized with chloromethyl, amino and phenylboronic acid groups.  

PubMed

The adsorptive separation of each steviol glycoside from aqueous solutions by polymeric adsorbents has attracted a lot of interest in recent years. The adsorption properties of chloromethylated cross-linked poly(styrene-co-divinylbenzene) macroporous resins, functionalised with chloromethyl, amino and phenylboronic acid groups, towards rebaudioside A and stevioside were studied. The results revealed that the resins with amino and phenylboronic acid groups preferred to adsorb stevioside rather than rebaudioside A, and their adsorption kinetics fitted a pseudo-second-order model. Isothermal equilibrium curves of rebaudioside A and stevioside showed a good fitness with the Langmuir and Freundlich models. The adsorption of rebaudioside A and stevioside onto resins was a spontaneous and exothermic process as indicated by the negative values in free energy and enthalpy. Results from the resin-packed column demonstrated that an effluent rich in rebaudioside A (purity 98%) was obtained prior to the breakthrough point of stevioside. PMID:24767024

Ye, Fayin; Yang, Ruijin; Hua, Xiao; Zhao, Guohua

2014-09-15

128

Determinants of exposure to inhalable particulate, wood dust, resin acids, and monoterpenes in a lumber mill environment.  

PubMed

In a lumber mill in the northern inland region of British Columbia, Canada, we measured inhalable particulate, resin acid, and monoterpene exposures, and estimated wood dust exposures. Potential determinants of exposure were documented concurrently, including weather conditions, tree species, wood conditions, jobs, tasks, equipment used, and certain control measures. Over 220 personal samples were taken for each contaminant. Geometric mean concentrations were 0.98 mg/m3 for inhalable particulate, 0.49 mg/m3 for estimated wood dust, 8.04 micrograms/m3 for total resin acids, and 1.11 mg/m3 for total monoterpenes. Multiple regression models for all contaminants indicated that spruce and pine produced higher exposures than alpine fir or mixed tree species, cleaning up sawdust increased exposures, and personnel enclosure was an effective means of reducing exposures. Sawing wood in the primary breakdown areas of the mill was the main contributor to monoterpene exposures, so exposures were highest for the barker operator, the head rig operator, the canter operator, the board edgers, and a roving utility worker in the sawmill, and lowest in the planer mills (after kiln drying of the lumber) and yard. Cleaning up sawdust, planing kiln-dried lumber, and driving mobile equipment in the yard substantially increased exposures to both inhalable particulate and estimated wood dust. Jobs at the front end of the sawmill where primary breakdown of the logs takes place had lower exposures. Resin acid exposures followed a similar pattern, except that yard driving jobs did not increase exposures. PMID:10432869

Teschke, K; Demers, P A; Davies, H W; Kennedy, S M; Marion, S A; Leung, V

1999-05-01

129

Long-term impact of acid resin waste deposits on soil quality of forest areas I. Contaminants and abiotic properties.  

PubMed

Acid resins are residues characterised by elevated concentrations of hydrocarbons and trace elements, which were produced by mineral oil industries in Central Europe during the first half of the last century. Due to the lack of environmental legislation at that time, these wastes were dumped into excavated ponds in public areas without further protection. In this work, the long-term effects of such resin deposits on soil quality of two forest areas (Bayern, Germany) were assessed. We evaluated the distribution and accumulation of contaminants in the surroundings of the deposits, where the waste was disposed of about 60 years ago. General soil chemical properties such as pH, C, N and P content were also investigated. Chemical analysis of resin waste from the deposits revealed large amounts of potential contaminants such as hydrocarbons (93 g kg(-1)), As (63 mg kg(-1)), Cd (24 mg kg(-1)), Cu (1835 mg kg(-1)), Pb (8100 mg kg(-1)) and Zn (873 mg kg(-1)). Due to the location of the deposits on a hillside and the lack of adequate isolation, contaminants have been released downhill despite the solid nature of the waste. Five zones were investigated in each site: the deposit, three affected zones along the plume of contamination and a control zone. In affected zones, contaminants were 2 to 350 times higher than background levels depending on the site. In many cases, contaminants exceeded the German environmental guidelines for the soil-groundwater path and action levels based on extractable concentrations. Resin contamination yielded larger total C/total N ratios in affected zones, but no clear effect was observed on absolute C, N and P concentrations. In general, no major acidification effect was reported in affected zones. PMID:18775554

Pérez-de-Mora, Alfredo; Madejón, Engracia; Cabrera, Francisco; Buegger, Franz; Fuss, Roland; Pritsch, Karin; Schloter, Michael

2008-11-15

130

Vapor-phase esterification of acetic acid with ethanol catalyzed by a macroporous sulfonated styrene-divinylbenzene (20%) resin  

SciTech Connect

The kinetics of the vapor-phase (85-120/sup 0/C) esterification of acetic acid with ethyl alcohol, at atmospheric pressure, catalyzed by a macroporous sulfonated styrene-divinylbenzene (DVB;20%) resin, has been studied. A simple first-order model (r = kp/sub 1/) fits experimental kinetic data properly for a constant reactants ratio. Discussion by means of L-H-H-W models shows that the rate-controlling step is the surface reaction with a single-site mechanism. The apparent activation energy is 4000 cal/mol.

Gimenez, J.; Costa, J.; Cervera, S.

1987-02-01

131

Selective recovery of Cr and Cu in leachate from chromated copper arsenate treated wood using chelating and acidic ion exchange resins.  

PubMed

The purpose of this study was to selectively remove chromium and copper from CCA-treated wood acid leachates (initial concentrations of 447-651 mg As l(-1), 374-453 mg Cu l(-1) and 335-622 mg Cr l(-1)) using ion exchange resins and precipitation techniques. Batch experiments revealed that the chelating resin Dowex M4195 had a high copper selectivity in the presence of chromium while the Amberlite IR120 resin had a high chromium sorption capacity. Combining M4195 and IR120 resins in four successive columns, made with Plexiglas tube, led to 96% copper extraction and 68% chromium extraction. NH(4)OH (4M) efficiently eluted copper from the chelating resin while H(2)SO(4) (10%v/v) was used for IR120 resin elution. Copper and chromium recovery by elution reached 94% and 81%, respectively. Successive sorption and elution steps using M4195 and IR120 ion exchange resins presented similar metal removal capacities over the five cycles. No resin deterioration was observed but the results suggested arsenic bulk diffusion into the M4195 resin. Successive treatments of CCA-treated wood leachate with M4195 and IR120 allowed for copper and chromium removal while arsenic could be extracted by coagulation treatment with ferric chloride and precipitation with Ca(OH)(2) at pH 5.7. This final process led to 99.9% arsenic removal. The final effluent contained less than 1 mg l(-1) of arsenic, chromium and copper. PMID:19446391

Janin, Amélie; Blais, Jean-François; Mercier, Guy; Drogui, Patrick

2009-09-30

132

A quantitative study of enamel acid etch patterns on surfaces used for retention of resin-bonded fixed prostheses.  

PubMed

This study investigated the quality of in vivo etch patterns on the bonding surfaces of 46 abutment teeth following acid etching with 37% phosphoric acid for 30 seconds. Two-stage putty and light bodied addition cured silicone impressions of the etched lingual surfaces were used to form replicas that were then viewed using the scanning electron microscope. Over 69% of the lingual bonding surface area of incisors, canine and premolars were unetched, 16% barely etched, 7% etched and less than 2% ideally etched. There was no significant difference in the quality of etch between different tooth types. There was a significantly greater proportion of poorly etched enamel towards the cervical margin in comparison with the occlusal half. This may have implications in retention of resin bonded bridges. PMID:16180638

Hobson, R S; Crotty, T; Thomason, J M; Jepson, N J A

2005-09-01

133

EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM SPHERICAL RESORCINOL-FORMALDEHYDE RESIN  

SciTech Connect

Ion Exchange column loading and elution of cesium from spherical resorcinol-formaldehyde resin have been conducted for two potential non-acid eluants -(NH{sub 4}){sub 2}CO{sub 3} and CH{sub 3}COONH{sub 4}. The results revealed encouraging cesium elution performance. 100% elution was achieved in at most 22 hours ({approx}28 bed volumes) of elution. Elution performance was fairly high at 6 hours ({approx}8 bed volumes) of elution for some of the eluants and also practically comparable to the benchmark acid eluant (HNO{sub 3}). Hence, it is quite possible 100% percent elution will be closer to the 6th hour than the 22nd hour. Elution is generally enhanced by increasing the concentration and pH of the eluants, and combining the eluants.

Adu-Wusu, K.; Nash, C.; Pennebaker, F.

2011-10-23

134

EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM RESORCINOL-FORMALDEHYDE RESIN  

Microsoft Academic Search

Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selected for use in the Hanford Waste Treatment and Immobilization Plant (WTP). It is also the primary ion exchange material under consideration for SCIX at

K. Adu-Wusu; F. Pennebaker

2010-01-01

135

Degree of cure and fracture properties of experimental acid-resin modified composites under wet and dry conditions  

PubMed Central

Objective Evaluate the effects of core structure and storage conditions on the mechanical properties of acid-resin modified composites and a control material by three-point bending and conversion measurements 15 min and 24 h after curing. Methods The monomers pyromellitic dimethacrylate (PMDM), biphenyldicarboxylic-acid dimethacrylate (BPDM), (isopropylidene-diphenoxy)bis(phthalic-acid) dimethacrylate (IPDM), oxydiphthalic-acid dimethacrylate (ODPDM), and Bis-GMA were mixed with triethyleneglycol dimethacrylate (TEGDMA) in a 40/60 molar ratio, and photo-activated. Composite bars (Barium-oxide-glass/resin = 3/1 mass ratio, (2 × 2 × 25) mm, n = 5) were light-cured for 1 min per side. Flexural strength (FS), elastic modulus (E), and work-of-fracture (WoF) were determined in three-point bending after 15 min (stored dry); and after 24 h under dry and wet storage conditions at 37 °C. Corresponding degrees of conversion (DC) were evaluated by Fourier transform infrared spectroscopy. Data was statistically analyzed (2-way analysis of variance, ANOVA, Holm-Sidak, p < 0.05). Results Post-curing significantly increased FS, E and DC in nearly all cases. WoF did not change, or even decreased with time. For all properties ANOVA found significant differences and interactions of time and material. Wet storage reduced the moduli and the other properties measured with the exception of FS and WoF of ODPDM; DC only decreased in BPDM and IPDM composites. Significance Differences in core structure resulted in significantly different physical properties of the composites studied with two phenyl rings connected by one ether linkage as in ODPDM having superior FS, WoF and DC especially after 24 h under wet conditions. As expected, post-curing significantly contributed to the final mechanical properties of the composites, while wet storage generally reduced the mechanical properties.

Lopez-Suevos, Francisco; Dickens, Sabine H.

2008-01-01

136

Extraction of Cu(II) from sulfuric acid by macrocycle-synergized cation exchange. Comparing a novel impregnated resin with its solvent-extraction analog  

Microsoft Academic Search

A novel extractive resin employing the tetradentate macrocyclic ionophore tetrathia-14-crown-4 (TT14C4) has been demonstrated via impregnation of strong-acid poly(styrene-divinylbenzene) cation-exchange beads. Following uptake of several weight percent TT14C4, the sulfonic acid resin exhibits a 10-100-fold enhancement in the cation-exchange extraction of Cu(II) as expressed by the Cu(II) distribution coefficient (D[sub Cu]). Since extraction of Cu(II) by unfunctionalized poly(styrene-divinylbenzene) impregnated with

Bruce A. Moyer; G. N. Case; Spiro D. Alexandratos; A. Amanda. Kriger

1993-01-01

137

Effect of adhesive hydrophilicity and curing-time on the permeability of resins bonded to water vs. ethanol-saturated acid-etched dentin  

PubMed Central

Objective This study examined the ability of five comonomer blends (R1-R5) of methacrylate-based experimental dental adhesives solvated with 10 mass% ethanol, at reducing the permeability of acid-etched dentin. The resins were light-cured for 20, 40 or 60 s. The acid-etched dentin was saturated with water or 100% ethanol. Method Human unerupted third molars were converted into crown segments by removing the occlusal enamel and roots. The resulting crown segments were attached to plastic plates connected to a fluid-filled system for quantifying fluid flow across smear layer-covered dentin, acid-etched dentin and resin-bonded dentin. The degree of conversion of the resins was measured using Fourier transform infrared spectroscopy. Result Application of the most hydrophobic comonomer blend (R1) to water-saturated dentin produced the smallest reductions in dentin permeability (31.9, 44.1 and 61.1% after light-curing for 20, 40 or 60 s respectively). Application of the same blend to ethanol-saturated dentin reduced permeability of 74.1, 78.4 and 81.2%, respectively (p<0.05). Although more hydrophilic resins produced larger reductions in permeability, the same trend of significantly greater reductions in ethanol-saturated dentin over that of water-saturated dentin remained. This result can be explained by the higher solubility of resins in ethanol vs. water. Significance The largest reductions in permeability produced by resins were equivalent but not superior, to those produced by smear layers. Resin sealing of dentin remains a technique-sensitive step in bonding etch-and-rinse adhesives to dentin.

Cadenaro, Milena; Breschi, Lorenzo; Rueggeberg, Frederick A.; Agee, Kelli; Di Lenarda, Roberto; Carrilho, Marcela; Tay, Franklin R.; Pashley, David H.

2009-01-01

138

Salicylic acid and derivatives anchored on poly(styrene- co-divinylbenzene) resin and membrane via a diazo bridge: Synthesis, characterisation and application to metal extraction  

Microsoft Academic Search

New materials for chelating solid-phase extraction have been prepared by grafting of salicylic acid and derivatives on poly(styrene-co-divinylbenzene) based sorbents. These sorbents are either resin bead-shaped Amberlite® XAD-4 or membrane disk-shaped Empore™ SDB-XC. Grafting has been achieved via –NN– spacer. The grafted ligands are salicylic acid (SA), its dimer form methylenedisalicylic acid (MDSA) and trimer form aurintricarboxylic form (ATA) in

Sabrina Boussetta; Catherine Branger; André Margaillan; Jean-Luc Boudenne; Bruno Coulomb

2008-01-01

139

Esterification of oleic acid in a three-phase, fixed-bed reactor packed with a cation exchange resin catalyst.  

PubMed

Esterification of oleic acid was performed in a three-phase fixed-bed reactor with a cation exchange resin catalyst (Amberlyst-15) at high temperature, which was varied from 80 to 120 °C. The fatty acid methyl ester (FAME) yields in the fixed-bed reactor were increased with increases in the reaction temperature, methanol flow rate and bed height. Moreover, the FAME yields were higher than those obtained using a batch reactor due to an equilibrium shift toward the product that resulted from continuous evaporation of the produced water. In addition, there was no catalyst deactivation during the esterification of oleic acid. However, addition of sunflower oil to the oleic acid reduced the FAME yield obtained from simultaneous esterification and transesterification. The FAME yield was 97.5% at a reaction temperature of 100 °C in the fixed-bed with a height of 5 cm when the methanol and oleic acid feed rates were 8.6 and 9.0 mL/h, respectively. PMID:20855192

Son, Sung Mo; Kimura, Hiroko; Kusakabe, Katsuki

2011-01-01

140

Binding and elution behavior of small deoxyribonucleic acid fragments on a strong anion-exchanger multimodal chromatography resin.  

PubMed

The separation behavior of small single-stranded from double-stranded DNA molecules has been determined on a multimodal (mixed-mode) chromatography system. The resin used is a strong anion exchanger which also modulates hydrophobic recognition. The intrinsic differences between single- and double-stranded DNAs concerning charge, hydrophobicity and three-dimensional structure render this form of MMC suitable for separation of the different nucleic acid molecules. All DNAs tested bound strongly to the resin and they could be eluted with increasing NaCl concentrations. Each homopolymeric ssDNA sample resulted in a base-specific elution pattern when using a linear NaCl gradient. The elution order was poly(dA)

Matos, Tiago; Queiroz, João A; Bülow, Leif

2013-08-01

141

Highly efficient co-removal of copper (II) and phthalic acid with self-synthesized polyamine resin.  

PubMed

A novel method was proposed for efficient co-removal of Cu (II) and phthalic acid (PA) using self-synthesized polyamine resin (R-NH(2)). The adsorption properties of R-NH(2) were thoroughly investigated by equilibrium, kinetic and dynamic tests in sole and binary systems at pH 5.0. The Freundlich model was a good fit for all the isotherm data, showing higher Kf values in the binary system than the sole system. The pseudo-second-order kinetic equation showed a better correlation to the experimental data in all cases and PA uptake was much faster than that of Cu (II). R-NH(2) showed highest adsorption capacities to both Cu (II) and PA among the five tested resins. Moreover, the presence of PA markedly enhanced the adsorption of Cu (II), being around 3.5 times of that of the sole system. The adsorption of PA was also slightly increased when Cu (II) was coexistent. Furthermore, using Fourier transform infrared spectrometry (FTIR) and species calculations, possible mechanisms were proposed that Cu (II) coordinated with -NH(2) and negative PA species interacted with -NH(3)(+) by electrostatic attraction. [Cu-PA] complex in the binary system possessed a much higher affinity than free Cu (II) to chelating with -NH(2), resulting in mutual enhancement. PMID:24804663

Ling, Chen; Liu, Fu-Qiang; Long, Chao; Wei, Meng-Meng; Li, Aimin

2014-01-01

142

In vitro metabolism, permeation, and brain availability of six major boswellic acids from Boswellia serrata gum resins.  

PubMed

Boswellia serrata gum resin extracts (BSE) revealed potent anti-inflammatory actions in preclinical and clinical studies. In 2002 BSE was assigned an orphan drug status by the European Medicines Agency (EMA) for the treatment of peritumoral edema. In the past pharmacological effects of BSE were mainly attributed to 11-keto-?-boswellic acid (KBA) and 3-acetyl-11-keto-?-boswellic acid (AKBA). Therefore pharmacokinetic and pharmacodynamic studies focused mainly on these two boswellic acids (BAs). However, other BAs, like ?-boswellic acid (?BA), might also contribute to the anti-inflammatory actions of BSE. Here, we determined the metabolic stability, permeability and brain availability of six major BAs, that is, KBA, AKBA, ?BA, 3-acetyl-?-boswellic acid (A?BA), ?-boswellic acid (?BA), and 3-acetyl-?-boswellic acid (A?BA). For permeability studies, the Caco-2 model was adapted to physiological conditions by the addition of bovine serum albumin (BSA) to the basolateral side and the use of modified fasted state simulated intestinal fluid (FaSSIF) on the apical side. Under these conditions the four BAs lacking the 11-keto moiety revealed moderate permeability. Furthermore the permeability of AKBA and KBA was improved compared to earlier studies. In contrast to A?- and A?BA, ?BA and ?BA were intensively metabolized after incubation with human and rat liver microsomes. Finally, the availability of all six major BAs could be confirmed in rat brain 8h after oral administration of 240mg/kg BSE to rats showing mean concentrations of 11.6ng/g for KBA, 37.5ng/g for AKBA, 485.1ng/g for ?BA, 1066.6ng/g for ?BA, 43.0ng/g for A?BA and 163.7ng/g for A?BA. PMID:23103296

Gerbeth, Kathleen; Hüsch, Jan; Fricker, Gert; Werz, Oliver; Schubert-Zsilavecz, Manfred; Abdel-Tawab, Mona

2013-01-01

143

Use of a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin column and propionic acid as an eluent in ion-exclusion/adsorption chromatography of aliphatic carboxylic acids and ethanol in food samples.  

PubMed

We developed an ion-exclusion/adsorption chromatography (IEAC) method employing a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin (PS-WCX) column with propionic acid as the eluent for the simultaneous determination of multivalent aliphatic carboxylic acids and ethanol in food samples. The PS-WCX column well resolved mono-, di-, and trivalent carboxylic acids in the acidic eluent. Propionic acid as the eluent gave a higher signal-to-noise ratio, and enabled sensitive conductimetric detection of analyte acids. We found the optimal separation condition to be the combination of a PS-WCX column and 20-mM propionic acid. Practical applicability of the developed method was confirmed by using a short precolumn with a strongly acidic cation-exchange resin in the H(+)-form connected before the separation column; this was to remove cations from food samples by converting them to hydrogen ions. Consequently, common carboxylic acids and ethanol in beer, wine, and soy sauce were successfully separated by the developed method. PMID:21558657

Mori, Masanobu; Hironaga, Takahiro; Kajiwara, Hiroe; Nakatani, Nobutake; Kozaki, Daisuke; Itabashi, Hideyuki; Tanaka, Kazuhiko

2011-01-01

144

Removal of sulfur dioxide and\\/or trioxide from gaseous effluents of fossil fuel operated power and steam plants. [weak acid, cation exchange resins  

Microsoft Academic Search

The removal of sulfur dioxide (SOâ) and\\/or sulfur trioxide (SOâ) from the gaseous effluents of fossil fuel burning steam and power plants using certain macroreticular, weak acid, cation exchange resins is described. The gaseous streams to be treated may be derived from other sources but the invention has particular utility and applicability in the control of pollution emanating from the

Kunin

1975-01-01

145

Adsorption characteristics of arsenic(III) and arsenic(V) on iron(III)-loaded chelating resin having lysine-N ?,N ?-diacetic acid moiety  

Microsoft Academic Search

An iron(III)-loaded chelating resin (Fe-LDA) with lysine-N?,N?-diacetic acid functional groups has been prepared and its adsorption characteristics for arsenic(III) and arsenic(V) have been examined. Arsenic(V) was strongly adsorbed to the resin in the pH range from 2 to 4, while arsenic(III) was moderately adsorbed between pH 8 and 10. The isotherm data for arsenic(V) at pH 3.5 fitted well to

H. Matsunaga; T. Yokoyama; R. J. Eldridge; B. A. Bolto

1996-01-01

146

Separation and conductimetric detection of C1-C7 aliphatic monocarboxylic acids and C1-C7 aliphatic monoamines on unfunctionized polymethacrylate resin columns.  

PubMed

The application of unfunctionized polymethacrylate resin (TSKgel G3000PWXL) as a stationary phase in liquid chromatography with conductimetric detection for C1-C7 aliphatic monocarboxylic acids (formic acid, acetic acid, propionic acid, butyric acid, isovaleric acid, valeric acid, 3,3-dimethylbutyric acid, 4-methylvaleric acid, hexanoic acid, 2-methylhexanoic acid, 5-methylhexanoic acid and heptanoic acid) and C1-C7 aliphatic monoamines (methylamine, ethylamine, propylamine, isobutylamine, butylamine, isoamylamine, amylamine, 1,3-dimethylbutylamine, hexylamine, 2-heptylamine and heptylamine) was attempted with C8 aliphatic monocarboxylic acids (2-propylvaleric acid, 2-ethylhexanoic acid, 2-methylheptanoic acid and octanoic acid) and C8 aliphatic monoamines (1,5-dimethylhexylamine, 2-ethylhexylamine, 1-methylheptylamine and octylamine) as eluents, respectively. Using 1 mM 2-methylheptanoic acid at pH 4.0 as the eluent, excellent separation and relatively high sensitive detection for these C1-C7 carboxylic acids were achieved on a TSKgel G3000PWXL column (150 mm x 6 mm i.d.) in 60 min. Using 2 mM octylamine at pH 11.0 as the eluent, excellent separation and relatively high sensitive detection for these C1-C7 amines were also achieved on the TSKgel G3000PWXL column in 60 min. PMID:15250420

Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi; Takeuchi, Toyohide

2004-06-11

147

Synthesis of chitosan resin possessing 3,4-diamino benzoic acid moiety for the collection\\/concentration of arsenic and selenium in water samples and their measurement by inductively coupled plasma-mass spectrometry  

Microsoft Academic Search

A chitosan resin functionalized with 3,4-diamino benzoic acid (CCTS-DBA resin) was newly synthesized by using a cross-linked chitosan (CCTS) as base material. The adsorption behavior of trace amounts of elements on the CCTS-DBA resin was examined by the pretreatment with a mini-column and measurement of the elements by inductively coupled plasma-Mass spectrometry (ICP–MS). Arsenic(V) could be retained on the CCTS-DBA

Akhmad Sabarudin; Koji Oshita; Mitsuko Oshima; Shoji Motomizu

2005-01-01

148

Flow injection online spectrophotometric determination of uranium after preconcentration on XAD-4 resin impregnated with nalidixic acid.  

PubMed

In this work, spectrophotometer was used as a detector for the determination of uranium from water, biological, and ore samples with a flow injection system coupled with solid phase extraction. In order to promote the online preconcentration of uranium, a minicolumn packed with XAD-4 resin impregnated with nalidixic acid was utilized. The system operation was based on U(VI) ion retention at pH 6 in the minicolumn at flow rate of 15.2 mL min(-1). The uranium complex was removed from the resin by 0.1 mol dm(-3) HCl at flow rate of 3.2 mL min(-1) and was mixed with arsenazo III solution (0.05 % solution in 0.1 mol dm(-3) HCl, 3.2 mL min(-1)) and driven to flow through cell of spectrophotometer where its absorbance was measured at 651 nm. The influence of chemical (pH and HCl (as eluent and reagent medium) concentration) and flow (sample and eluent flow rate and preconcentration time) parameters that could affect the performance of the system as well as the possible interferents was investigated. At the optimum conditions for 60 s preconcentration time (15.2 mL of sample volume), the method presented a detection limit of 1.1 ?g L(-1), a relative standard deviation (RSD) of 0.8 % at 100 ?g L(-1), enrichment factor of 30, and a sample throughput of 42 h(-1), whereas for 300 s of the preconcentration time (76 mL of sample volume), a detection limit of 0.22 ?g L(-1), a RSD of 1.32 % at 10 ?g L(-1), enrichment factor of 150, and a sampling frequency of 11 h(-1) were reported. PMID:22580790

Shahida, Shabnam; Ali, Akbar; Khan, Muhammad Haleem; Saeed, Muhammad Mufazzal

2013-02-01

149

Preparation of urine samples for liquid-chromatographic determination of catecholamines: bonded-phase phenylboronic acid, cation-exchange resin, and alumina adsorbents compared.  

PubMed

We compared results for the liquid-chromatographic determination of free norepinephrine and epinephrine in urine after purifying the catechols by the following methods: (a) acid-washed alumina, (b) weak cation-exchange resin (WCX), (c) a combination of weak cation-exchange resin followed by alumina (WCX-alumina), and (d) commercially available phenylboronic acid adsorbent. We evaluated analytical specificity, sensitivity, recovery, and turnaround time. The WCX-alumina combination produced the most sensitive and specific chromatograms for urinary catecholamines; the other methods took less processing time. Neither WCX nor alumina alone was suitable for routine work because of chromatographic interferences in a significant proportion of urines. The phenylboronic acid method is adequately sensitive and specific for norepinephrine and epinephrine, and samples can be assayed faster. Thus it provides a compromise between the high analytical performance of the WCX-alumina method and the speed of the WCX and alumina methods. PMID:3967369

Wu, A H; Gornet, T G

1985-02-01

150

Catalysis with Metal Cation-Exchanged Resins  

Microsoft Academic Search

There have been a paucity of reports dealing with catalytic reactions involving metal or metal cations incorporated into ion-exchange resins. It is the objective of this review to summarize these reactions and to discuss in detail one such resin, a perfluorinated Exchange polymer, PFIEP. here survey two resin types, polystyrene sulfonic acid (PSSA) and PFIEP or Nafion [11. Acid catalysis

F. J. Waller

1986-01-01

151

Esterification of maleic acid with ethanol over cation-exchange resin catalysts  

Microsoft Academic Search

Diethyl maleate is an important intermediate extensively used in the production of latex emulsion polymers, thermoplast and thermoset plastics. The current paper delineates the efficacy of several heterogeneous catalysts, such as Indion-170, Amberlyst-36, Amberlyst-15, Amberlite IRA 120, 20% DTP\\/K-10 (dodecatungstophosphoric acid supported on K-10 clay) in the esterification of maleic acid with ethanol at reflux. Amongst these Indion-170, Amberlyst-36, Amberlyst-15

G. D. Yadav; M. B Thathagar

2002-01-01

152

AN ANALYSIS OF THE CHARACTERISTICS OF ANION EXCHANGE RESINS SUITABLE FOR THE URANIUM RECOVERY FROM ACID LEACH LIQUORS  

Microsoft Academic Search

A brief outline of the ion exchange process for U extraction is ; presented with special reference to the aspects of interest in resin evaluation. ; The various properties of the resin which play an important role in the ion ; exchange operation are discussed in some detail. (W.L.H.);

R. E. Robinson; R. G. Velthuis; E. T. Pinkney

1959-01-01

153

Comparison of gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry for the determination of fatty and resin acids in paper mill process waters  

Microsoft Academic Search

A comparative study of the performance of liquid chromatography (LC)–atmospheric pressure chemical ionisation (APCI)–mass spectrometry (MS) and gas chromatography (GC)–mass spectrometry techniques for the determination of resin and fatty acids from paper mill process waters was carried out. These compounds are responsible for the high toxicity of paper mill effluents and little research has been carried out regarding their analysis

A Latorre; A Rigol; S Lacorte; D Barceló

2003-01-01

154

Measurement and Theoretical Description of Ion Sorption and Diffusion of Water and Counterions in a Cation Exchange Resin Bearing Sulfonic Acid Groups  

Microsoft Academic Search

Sorption of LiCl, diffusion of Li+ions, and diffusion of water have been studied as a function of the salt concentration in a synthesized cation-exchange resin bearing sulfonic acid groups. The Li+diffusion shows a maximum in the salt concentration dependence reflecting on one side the enhanced diffusion due to screening of the fixed charges on the charged matrix and on the

H. van Keulen; J. G. Hollander; J. A. M. Smit

1997-01-01

155

Effect of acid etching duration on tensile bond strength of composite resin bonded to erbium:yttrium–aluminium–garnet laser-prepared dentine. Preliminary study  

Microsoft Academic Search

The purpose of this study was to compare the tensile bond strength of composite resin bonded to erbium:yttrium–aluminium–garnet\\u000a (Er:YAG) laser-prepared dentine after different durations of acid etching. The occlusal third of 68 human third molars was\\u000a removed in order to expose the dentine surface. The teeth were randomly divided into five groups: group B (control group),\\u000a prepared with bur and

M. Chousterman; D. Heysselaer; S. M. Dridi; F. Bayet; B. Misset; L. Lamard; A. Peremans; C. Nyssen-Behets; S. Nammour

2010-01-01

156

Design, Synthesis, Application and Recovery of Guar Gum 5Amino Salicylic Acid Hydroximate [GASAH] Resin for Selective Separation and Determination of Trace and Heavy Metal Ions  

Microsoft Academic Search

The ion exchange method is applied for removal of heavy metal ions from industrial wastewater and determines the applicability of synthesized guar gum 5-amino salicylic acid hydroximate (GASAH) resin. The effect of experimental parameters such as pH, agitation speed, contact time, adsorbent dose and flow rate on the removal of metal ions has been studied. Fourier-transform infrared spectrum and elemental

A. V. Singh; Naresh Kumar Sharma

2012-01-01

157

Acetyl-11-keto-beta-boswellic acid, a constituent of a herbal medicine from Boswellia serrata resin, attenuates experimental ileitis.  

PubMed

The gum resin extract from Boswellia serrata (H15), an herbal product, was recently shown to have positive therapeutic effects in inflammatory bowel disease (IBD). However, the mechanisms and constituents responsible for these effects are poorly understood. This study examined the effect of the Boswellia extract and its single constituent acetyl-11-keto-beta-boswellic acid (AKBA) on leukocyte-endothelial cell interactions in an experimental model of IBD. Ileitis was induced by two subcutaneous injections of indomethacin (7.5 mg/kg) in Sprague-Dawley rats 24 h apart. Rats also received oral treatment with the Boswellia extract (H15) or AKBA at two different doses (low and high) equivalent to recommendations in human disease over 2 days. Controls received only the carriers NaHCO3 (subcutaneously) and tylose (orally). Effects of treatment were assessed by intravital microscopy in ileal submucosal venules for changes in the number of rolling and adherent leukocytes and by macroscopic and histological scoring. Increased leukocyte-endothelial cell adhesive interactions and severe tissue injury accompanied indomethacin-induced ileitis. Treatment with the Boswellia extract or AKBA resulted in a dose-dependent decrease in rolling (up to 90%) and adherent (up to 98%) leukocytes. High-dose Boswellia extract as well as both low- and high-dose AKBA significantly attenuated tissue injury scores. Oral therapy with the Boswellia extract or AKBA significantly reduces macroscopic and microcirculatory inflammatory features normally associated with indomethacin administration, indicating that the anti-inflammatory actions of the Boswellia extract in IBD may be due in part to boswellic acids such as AKBA. PMID:11355324

Krieglstein, C F; Anthoni, C; Rijcken, E J; Laukötter, M; Spiegel, H U; Boden, S E; Schweizer, S; Safayhi, H; Senninger, N; Schürmann, G

2001-04-01

158

Resin glycosides from Porana duclouxii.  

PubMed

A new intact resin glycoside (3) and two glycosidic acids (1 and 2), all having a common trisaccharide moiety and (11S)-hydroxytetradecanoic acid or (3S,11S)-dihydroxytetradecanoic acid as the aglycone, were obtained from the roots of Porana duclouxii. Their structures were elucidated by spectroscopic analyses and chemical correlations. These compounds represent the first examples of resin glycosides from the genus Porana. PMID:24320876

Ding, Wen-Bing; Zhang, Dai-Gui; Liu, Chun-Jie; Li, Guan-Hua; Li, You-Zhi

2014-01-01

159

Phosphorus-containing bisimide resins  

NASA Technical Reports Server (NTRS)

The production of fire-resistant resins particularly useful for making laminates with inorganic fibers such as graphite fibers is discussed. The resins are by (1) condensation of an ethylenically unsaturated cyclic anhydride with a bis(diaminophenyl) phosphine oxide, and (2) by addition polymerization of the bisimide so obtained. Up to about 50%, on a molar basis, of benzophenonetetracarboxylic acid anhydride can be substituted for some of the cyclic anhydride to alter the properties of the products. Graphite cloth laminates made with these resins show 800 C char yields greater than 70% by weight in nitrogen. Limiting oxygen indexes of more than 100% are determined for these resins.

Varma, I. K.; Fohlen, G. M.; Parker, J. A. (inventors)

1981-01-01

160

Advanced thermoplastic resins, phase 1  

NASA Technical Reports Server (NTRS)

Eight thermoplastic polyimide resin systems were evaluated as composite matrix materials. Two resins were selected for more extensive mechanical testing and both were versions of LaRC-TPI (Langley Research Center - Thermoplastic Polyimide). One resin was made with LaRC-TPI and contained 2 weight percent of a di(amic acid) dopant as a melt flow aid. The second system was a 1:1 slurry of semicrystalline LaRC-TPI powder in a polyimidesulfone resin diglyme solution. The LaRC-TPI powder melts during processing and increases the melt flow of the resin. Testing included dynamic mechanical analysis, tension and compression testing, and compression-after-impact testing. The test results demonstrated that the LaRC-TPI resins have very good properties compared to other thermoplastics, and that they are promising matrix materials for advanced composite structures.

Hendricks, C. L.; Hill, S. G.; Falcone, A.; Gerken, N. T.

1991-01-01

161

Galbanic acid, a cytotoxic sesquiterpene from the gum resin of Ferula asafoetida, blocks protein farnesyltransferase.  

PubMed

Farnesylation of the activated RAS oncogene product by protein farnesyltransferase (FTase) is a critical step for its oncogenic function. Bioassay-guided purification of Ferula asafoetida (Umbelliferae) extract led to the isolation of the coumarin-derived sesquiterpene galbanic acid (1) as an active principal for FTase inhibitory activity, together with the four structurally related sesquiterpenes karatavicinol (2), umbelliprenin (3), farnesiferol B (4), and farnesiferol C (5). The 50 % inhibitory concentration (IC (50)) of 1 against FTase in an enzyme-based assay was calculated as 2.5 µM. Compound 1 also demonstrated potent inhibition of the proliferation of oncogenic RAS-transformed NIH3T3/Hras-F in a dose-dependent manner. The IC (50) value of 1 on the proliferation of oncogenic RAS-transformed NIH3T3/Hras-F cells was calculated as 16.2 µM, whereas its IC (50) value on control vector-transfected normal RAS-containing NIH3T3/ZIPneo cells was 58.5 µM. PMID:20560115

Cha, Mi-Ran; Choi, Yeon Hee; Choi, Chun Whan; Kim, Young Sup; Kim, Young-Kyoon; Ryu, Shi Yong; Kim, Young Ho; Choi, Sang Un

2011-01-01

162

Bead Settling During Cation and Anion Resin Separation  

Microsoft Academic Search

The production of ultrapure water by ion exchange requires thorough mixing of cationic and anionic resins. In many cases the resins are regenerated; requiring bead-type separation prior to chemical treatment with the respective acid or base. Resin separation is predictable based upon backwash conditions, resin properties and system geometry. An important factor in an accurate model is the drag coefficient

Bharathwaj Gopalakrishnan; Gary L. Foutch; Drew Fleck; Hasith Suriyapperuma

2012-01-01

163

Functional gel-type resin based palladium catalysts: The role of polymer properties in the hydrogenation of the C C bond of maleic and fumaric acids, the isomers of dicarboxylic acids  

Microsoft Academic Search

Functional gel-type resins (OFP) composed of 2-hydroxyethyl methacrylate (HEMA, 20mol%), styrene (60–77mol%) and diethylene glycol dimethacrylate, the crosslinking reagent (DEGDMA, 3–20mol%) are used as supports for palladium catalysts (0.25–2wt% Pd). The influence of polymer mass expansion on the activity of Pd\\/OFP catalysts in the hydrogenation of cis- and trans-isomers of unsaturated dicarboxylic acids, maleic (MA) and fumaric (FA), is examined.

A. Drelinkiewicz; A. Knapik; A. Waksmundzka-Góra; A. Bukowska; W. Bukowski; J. Noworól

2008-01-01

164

Preliminary Report on Evaluation of Potential Eluants for Non-Acid Elution of Cesium from Resorcinol-Formaldehyde Resin.  

National Technical Information Service (NTIS)

Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selec...

F. M. Pennebaker K. Adu-Wusu

2010-01-01

165

Lignin pyrolysis products, lignans, and resin acids as specific tracers of plant classes in emissions from biomass combustion  

Microsoft Academic Search

Biomass smoke aerosols contain thermally unaltered and partially altered biomarker compounds from major vegetation taxa. These compounds range from C[sub 8] to C[sub 31] and include phytosterols, lignans, phenolic products from lignin, and diterpenoids from resins. Certain of the higher molecular weight biomarkers are vaporized from the parent plant material and subsequently condense unaltered into the particle phase. Other compounds

Bernd R. T. Simoneit; W. F. Rogge; G. R. Cass; M. A. Mazurek; L. J. Standley; L. M. Hildemann

1993-01-01

166

Dentine sealing provided by smear layer/smear plugs vs. adhesive resins/resin tags.  

PubMed

The aim of this study was to evaluate the ability of five experimental resins, which ranged from hydrophobic to hydrophilic blends, to seal acid-etched dentine saturated with water or ethanol. The experimental resins (R1, R2, R3, R4, and R5) were evaluated as neat bonding agents (100% resin) or as solutions solvated with absolute ethanol (70% resin/30% ethanol). Fluid conductance was measured at 20 cm H(2)O hydrostatic pressure after sound dentine surfaces were: (i) covered with a smear layer; (ii) acid-etched; or (iii) bonded with neat or solvated resins, which were applied to acid-etched dentine saturated with water or ethanol. In general, the fluid conductance of resin-bonded dentine was significantly higher than that of smear layer-covered dentine. However, when the most hydrophobic neat resins (R1 and R2) were applied to acid-etched dentine saturated with ethanol, the fluid conductance was as low as that produced by smear layers. The fluid conductance of resin-bonded dentine saturated with ethanol was significantly lower than for resin bonded to water-saturated dentine, except for resin R4. Application of more hydrophobic resins may provide better sealing of acid-etched dentine if the substrate is saturated with ethanol instead of with water. PMID:17697173

Carrilho, Marcela R; Tay, Franklin R; Sword, Jeremy; Donnelly, Adam M; Agee, Kelli A; Nishitani, Yoshihiro; Sadek, Fernanda T; Carvalho, Ricardo M; Pashley, David H

2007-08-01

167

Distribution of 14 elements from two solutions simulating Hanford HLW Tank 102SY (acid-dissolved sludge and acidified supernate) on four cation exchange resins and five anion exchange resins having different functional groups  

Microsoft Academic Search

As part of the Tank Waste Remediation System program at Los Alamos, we evaluated a series of cation exchange and anion exchange resins for their ability to remove hazardous components from radioactive high-level waste (HLW). The anion exchangers were ReillexTM HPQ, a polyvinylpyridine resin, and four strong-base polystyrene resins having trimethyl, triethyl, tripropyl, and tributyl amine as their respective functional

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

1995-01-01

168

Preconcentration of seleno-amino acids on a XAD resin and determination in regional olive oils by SPE UPLC-ESI-MS/MS.  

PubMed

This study describes a method for seleno-amino acids determination in Argentinean olive oils. Preliminary total selenium determination in olive oils probed low concentrations (62.8±1.6 to 117.4±3.0 ?g/kg) and the necessity of implementing a preconcentration method. To this end a XAD® resin was employed as sorbent for selenomethionine (Se-Met), selenomethylselenocysteine (Se-MetSeCys), and selenocysteine (Se-Cys) preconcentration. Determinations were performed by UPLC-ESI-MS/MS. Recoveries were between 84% and 97% for the seleno-amino acids studied, reaching a detection limit of 0.09 ?g/kg, a precision of 10% (RSD, n=6), and an enhancement factor of 60-fold (6 for the extraction system and 10 for the preconcentration approach). The only detected Se species in the olive oils was Se-MetSeCys in concentrations ranging from 2.0 to 8.3 ?g/kg. PMID:24767074

Torres, Sabier; Cerutti, Soledad; Raba, Julio; Pacheco, Pablo; Silva, María Fernanda

2014-09-15

169

Adsorption of o-cresol and benzoic acid in an adsorber packed with an ion-exchange resin: A comparative study of diffusional models  

SciTech Connect

Both solid- and pore-diffusion models were employed to simulate the adsorption of o-cresol and benzoic acid in a fixed-bed adsorber packed with an anion-exchange resin. The equilibrium adsorption data were modeled by a Langmuir isotherm. When the shape of the adsorption isotherm was approximately linear (as in the case of o-cresol), both models agreed well with the experimental break-through data, and they could be effectively applied to predict the breakthrough curve of longer columns. For a favorable adsorption isotherm (say, benzoic acid), however, better results were obtained by using the solid-diffusion model. In addition to the shape of the adsorption isotherm, several factors, such as the type of adsorbent, modeling of equilibrium data, computation efficiency, and concentration dependence of the intraparticle diffusivity, should also be taken into account for selecting a suitable diffusion model.

Run-Tun Huang; Teh-Liang Chen; Hung-Shan Weng [National Cheng Kung Univ., Taiwan (China)

1994-10-01

170

PRELIMINARY REPORT ON EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM RESORCINOL-FORMALDEHYDE RESIN  

Microsoft Academic Search

Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selected for use in the Hanford Waste Treatment and Immobilization Plant (WTP). It is also the primary ion exchange material under consideration for SCIX at

K. Adu-Wusu; F. Pennebaker

2010-01-01

171

Effects of Resin Swelling and Substitution on Solid Phase Synthesis. (Reannouncement with New Availability Information).  

National Technical Information Service (NTIS)

Resins sold by several companies were examined for swelling, uniformity of beads, and substitution in the case of resins sold with the first amino acid attached. Effects of resin swelling, uniformity, and substitution on the solid phase synthesis of long,...

K. C. Pugh E. J. York J. M. Stewart

1992-01-01

172

Exposure of Atlantic salmon parr (Salmo salar) to a combination of resin acids and a water soluble fraction of diesel fuel oil: A model to investigate the chemical causes of pigmented salmon syndrome  

SciTech Connect

Pigmented salmon syndrome is a pollutant-induced hemolytic anemia and hyperbilirubinemia. As part of an investigation of this condition, S2 Atlantic salmon parr (Salmo salar) were exposed to a diesel fuel oil, water soluble fraction (WSF) in combination with a mixture of three resin acids (isopimaric, dehydroabietic, and abietic acids) in a continuous-flow freshwater system. The total nominal concentrations of resin acids in the exposure tanks were 10, 50, and 100 {micro}g/L; the diesel WSF was generated in situ and provided a mean hydrocarbon concentration of 2.0 {+-} 0.1 mg/L (n = 12) during the 9-d exposure period. Exposure to the diesel WSF alone depressed liver bilirubin UDP-glucuronosyl transferase (UDPGT) activity and induced phenol UDPGT activity. Exposure to the diesel WSF in the absence or presence of resin acids induced liver cytochrome P4501A and increased the concentrations in the plasma of the enzymes lactate dehydrogenase, alkaline phosphatase, and glutamic oxaloacetic transaminase. The combined exposure to diesel WSF with either 50 or 100 {micro}g/L total resin acid caused significant elevations in the concentrations of bilirubin in the plasma and many of these fish had yellow pigmentation on the ventral surface and around the gill arches. The results demonstrate that exposure to combinations of two groups of contaminants can result in the manifestation of toxic effects not apparent from exposure to either of these chemicals in isolation.

Croce, B. [Scottish Office Agriculture, Environment, and Fisheries Dept., Aberdeen (United Kingdom). Marine Lab.]|[Scottish Environmental Protection Agency, Aberdeen (United Kingdom). North East River Purification Board; Stagg, R.M. [Scottish Office Agriculture, Environment, and Fisheries Dept., Aberdeen (United Kingdom). Marine Lab.

1997-09-01

173

A comparative study of chelating and cationic ion exchange resins for the removal of palladium(II) complexes from acidic chloride media.  

PubMed

The increasing demand for palladium for technological application requires the development of ion exchange chromatography. Recently ion exchange chromatography has developed largely as a result of new types of ion exchangers available on the market of which two types are widely applied. One of them are selective (chelating) and modified ion exchangers and the other one are liquid exchangers. Two types of ion exchange resins such as chelating (Lewatit TP 214, Purolite S 920) and cationic (Chelite S, Duolite GT 73) ion exchangers are used for the recovery of palladium(II) complexes from chloride media (0.1-2.0M HCl-1.0M NaCl-0.0011 M Pd(II); 0.1-2.0M HCl-2.0M NaCl-0.0011M Pd(II)). The influence of concentration of hydrochloric acid, sodium chloride as well as the phase contact time on the degree of recovery of palladium(II) complexes was studied. Moreover, the amount of palladium(II) chlorocomplexes sorbed onto ion exchangers, the working ion exchange capacities and the weight and bed distribution coefficients were calculated in order to judge which of two types of resins possesses the best performance towards palladium(II) complexes. PMID:18980805

Hubicki, Zbigniew; Wo?owicz, Anna

2009-05-30

174

Influence of acidic eluent for retention behaviors of common anions and cations by ion-exclusion/cation-exchange chromatography on a weakly acidic cation-exchange resin in the H+ -form.  

PubMed

Influence of acidic eluent on retention behaviors of common anions and cations by ion-exclusion/cation-exchange chromatography (ion-exclusion/CEC) were investigated on a weakly acidic cation-exchange resin in the H(+)-form with conductivity. Sensitivities of analyte ions, especially weak acid anions (F(-) and HCOO(-)), were affected with degree of background conductivity level with pK(a1) (first dissociation constant) of acid in eluent. The retention behaviors of anions and cations were related to that of elution dip induced after eluting acid to separation column and injecting analyte sample. These results were largely dependent on the natures of acid as eluent. Through this study, succinic acid as the eluent was suitable for simultaneous separation of strong acid anions (SO(4)(2-), Cl(-), NO(3)(-) and I(-)), weak acid anions (F(-), HCOO(-) and CH(3)COO(-)), and cations (Na(+), K(+), NH(4)(+), Mg(2+) and Ca(2+)). The separation was achieved in 20 min under the optimum eluent condition, 20 mM succinic acid/2 mM 18-crown-6. Detection limits at S/N=3 ranged from 0.10 to 0.51 microM for strong acid anions, 0.20 to 5.04 microM for weak acid anions and 0.75 to 1.72 microM for cations. The relative standard deviations of peak areas in the repeated chromatographic runs (n=10) were in the range of 1.1-2.9% for anions and 1.8-4.5% for cations. This method was successfully applied to hot spring water containing strong acid anions, weak acid anions and cations, with satisfactory results. PMID:16546200

Mori, Masanobu; Tanaka, Kazuhiko; Satori, Tatsuya; Ikedo, Mikaru; Hu, Wenzhi; Itabashi, Hideyuki

2006-06-16

175

Resin composite restorative materials.  

PubMed

This paper surveys the most important developments in resin-based dental composites and focuses on the deficits (e.g. polymerization shrinkage) and strengths of the materials and their clinical implications. Moreover, differences between composite categories, such as hybrid, nanohybrid, microfilled, packable, ormocer-based, silorane-based, polyacid-modified composites (compomers) and flowable composites are highlighted, especially in view of their mechanical behaviour. In addition to the classical dimethacrylate-based composites, special attention is given to alternative monomers, such as siloranes, ormocers or high-molecular-weight dimethacrylate monomers (e.g. dimer acid-based dimethacrylates and tricyclodecane (TCD)-urethane), analysing their advantages, behaviour and abilities. Finally, the paper attempts to establish the needs and wishes of clinicians for further development of resin-based composites. PMID:21564116

Ilie, N; Hickel, R

2011-06-01

176

Synthesis of insulin-like growth factor I using N-methyl pyrrolidinone as the coupling solvent and trifluoromethane sulphonic acid cleavage from the resin.  

PubMed

Insulin-like growth factor I (IGF-I), a protein of 70 amino acid residues and 3 cystine bridges, has been synthesized by two solid phase Boc methods. The first method used N-methylpyrrolidinone as the solvent with single coupling cycles while the second synthesis used dimethylformamide and dichloromethane as the solvents with a double-coupling protocol. In both cases, trifluoroacetic acid/trifluoromethanesulphonic acid cleavage of the peptide from the resin was employed. Purification of the cleavage products followed by removal of the S-acetamidomethyl protecting groups gave reduced peptides which were then oxidized under conditions favouring the formation of the correct disulphide bonds. The purified synthetic IGF-I peptides were full agonists of natural IGF-I in a radioimmunoassay, in an IGF-I radioreceptor assay, in a bioassay which measures the stimulation of protein synthesis in rat L6 myoblasts and in an IGF-binding protein competitive binding assay. Moreover, in each of these assays, the synthetic IGF peptides were found to be at least 70% as potent as natural IGF-I. PMID:1964154

Bagley, C J; Otteson, K M; May, B L; McCurdy, S N; Pierce, L; Ballard, F J; Wallace, J C

1990-10-01

177

High-speed ion-exclusion chromatography of dissolved carbon dioxide on a small weakly acidic cation-exchange resin column with ion-exchange enhancement columns of conductivity detection.  

PubMed

The high-speed ion-exclusion chromatographic determination of dissolved carbon dioxide, i.e., carbonic acid, hydrogencarbonate or carbonate, with conductivity detection was obtained using a small column packed with a weakly acidic cation-exchange resin in the H+-form (40 mm long x 4.6 mm i.d., 3 microm-particle and 0.1 meq./ml-capacity). Two different ion-exchange resin columns, which were a strongly acidic cation-exchange resin in the K+-form and a strongly basic anion-exchange resin in the OH- -form, were connected after the separation column. The sequence of columns could convert dissolved carbon dioxide to KOH having high conductivity response. The enhancement effect for dissolved carbon dioxide could retain even on the vast chromatographic runs, by using the enhancement columns with high ion-exchange capacity above 1.0 meq./ml. The retention time was in 60 s at flow-rate of 1.2 ml/min. The calibration graph of dissolved carbon dioxide estimated as H2CO3- was linear in the range of 0.005-10 mM. The detection limit at signal to noise of 3 was 0.15 microM as H2CO3-. This method was applicable to several rainwater and tap water samples. PMID:16199234

Mori, Masanobu; Ikedo, Mikaru; Hu, Wenzhi; Helaleh, Murad I H; Xu, Qun; Itabashi, Hideyuki; Tanaka, Kazuhiko

2005-10-28

178

Processing large-diameter poly(L-lactic acid) microfiber mesh/mesenchymal stromal cell constructs via resin embedding: an efficient histologic method.  

PubMed

In this study, we performed a complete histologic analysis of constructs based on large diameter (?>?100??m) poly-L-lactic acid (PLLA) microfibers obtained via dry-wet spinning and rat Mesenchymal Stromal Cells (rMSCs) differentiated towards the osteogenic lineage, using acrylic resin embedding.In many synthetic polymer-based microfiber meshes, ex post processability of fiber/cell constructs for histologic analysis may face deterring difficulties, leading to an incomplete investigation of the potential of these scaffolds. Indeed, while polymeric nanofiber (fiber diameter = tens of nanometers)/cell constructs can usually be embedded in common histologic media and easily sectioned, preserving the material structure and the antigenic reactivity, histologic analysis of large polymeric microfiber/cell constructs in the literature is really scant. This affects microfiber scaffolds based on FDA-approved and widely used polymers such as PLLA and its copolymers. Indeed, for such constructs, especially those with fiber diameter and fiber interspace much larger than cell size, standard histologic processing is usually inefficient due to inhomogeneous hardness and lack of cohesion between the synthetic and the biological phases under sectioning.In this study, the microfiber/MSC constructs were embedded in acrylic resin and the staining/reaction procedures were calibrated to demonstrate the possibility of successfully employing histologic methods in tissue engineering studies even in such difficult cases. We histologically investigated the main osteogenic markers and extracellular matrix molecules, such as alkaline phosphatase, osteopontin, osteocalcin, TGF-?1, Runx2, Collagen type I and the presence of amorphous, fibrillar and mineralized matrix. Biochemical tests were employed to confirm our findings. This protocol permitted efficient sectioning of the treated constructs and good penetration of the histologic reagents, thus allowing distribution and expression of almost all the tested molecules to be revealed. Our results demonstrated that it is possible to perform histologic analyses of large-diameter PLLA-based microfiber scaffold/MSC constructs that face the failure of standard histologic procedures. PMID:25029413

D'Alessandro, Delfo; Pertici, Gianni; Moscato, Stefania; Metelli, Maria Rita; Danti, Sabrina; Nesti, Claudia; Berrettini, Stefano; Petrini, Mario; Danti, Serena

2014-08-01

179

Novel silica-based ion exchange resin  

SciTech Connect

Eichrom`s highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchange systems. Unlike conventional resins, Diphonix resin contains chelating ligands that are diphosphonic acid groups that recognize and remove the targeted metals and reject the more common elements such as sodium, calcium and magnesium. This latter property makes Diphonix ideal for many industrial scale applications, including those involving waste treatment. For treatment of low-level, transuranic (TRU) and high- level radioactive wastes, Diphonix`s polystyrene backbone hinders its application due to radiolytic stability of the carbon-hydrogen bonds and lack of compatibility with expected vitrification schemes. Polystyrene-based Diphonix is approximately 60% carbon- hydrogen. In response to an identified need within the Department of Energy for a resin with the positive attributes of Diphonix that also exhibits greater radiolytic stability and final waste form compatibility, Eichrom has successfully developed a new, silica-based resin version of Diphonix. Target application for this new resin is for use in environmental restoration and waste management situations involving the processing of low-level, transuranic and high-level radioactive wastes. The resin can also be used for processing liquid mixed waste (waste that contains low level radioactivity and hazardous constituents) including mixed wastes contaminated with organic compounds. Silica-based Diphonix is only 10% carbon-hydrogen, with the bulk of the matrix silica.

NONE

1997-11-01

180

Use of Anion Exchange Resin and Acidic-Organic Mixtures in the Separation of Na, Cs and Ba.  

National Technical Information Service (NTIS)

A systematic study was carried out on the adsorption of Na, Cs and Ba on Dowex 1x8 from various concentrations of hydrochloric and nitric acid solutions. The addition of water-miscible organic solvents to the acidic solutions was found to increase the Ksu...

R. Shabana H. Ruf

1977-01-01

181

Preparation of Cation-Exchange Resin from Lignin  

Microsoft Academic Search

Lignin precipitated from black liquor of soda pulping of bagasse was used to prepare cation-exchange resin. The effects of sulfuric acid treatment and concentration of phenol and formaldehyde on the properties of the prepared cation-exchange resin were investigated. It was found that sulfonated resinified phenolized lignin gave a resin with an ion-exchange capacity higher than that of resin, which resulted

S. Kamel

2005-01-01

182

Stability Of A Carbon-Dioxide-Removing Resin  

NASA Technical Reports Server (NTRS)

Report describes experiments determing long-term chemical stability of IRA-45, commerical ion-exchange resin candidate for use in removing CO2 from atmosphere of Space Station. In proposed system, cabin air passes through resin, and acidic CO2 absorbed by weakly-basic hydrated diethylenetriamine bonded to porous resin substrate. When resin absorbs all CO2, disconnects from airstream and heated with steam to desorb CO2. Resin reuseable. Removed by post-treating process air with phosphoric acid on charcoal. Other chemicals removed by trace-contaminant-control subsystem of Space Station.

Wydeven, Theodore; Wood, Peter

1990-01-01

183

21 CFR 177.1555 - Polyarylate resins.  

Code of Federal Regulations, 2010 CFR

...Identity. Polyarylate resins (1, 3-benzenedicarboxylic acid, diphenyl ester, polymer with diphenyl 1,4-benzenedicarboxylate and 4-4â²-(1-methylethylidine) bis(phenol)) are formed by melt polycondensation of...

2009-04-01

184

21 CFR 177.1555 - Polyarylate resins.  

Code of Federal Regulations, 2010 CFR

...Identity. Polyarylate resins (1, 3-benzenedicarboxylic acid, diphenyl ester, polymer with diphenyl 1,4-benzenedicarboxylate and 4-4â²-(1-methylethylidine) bis(phenol)) are formed by melt polycondensation of...

2010-01-01

185

Novel silica-based ion exchange resin  

SciTech Connect

Shortcomings of chelating resins have been addressed by a new class of ion exchange resins called dual mechanism bifunctional polymers (DMBPs). DMBPs use hydrophilic cation exchange ligands with rapid uptake kinetics and use chelating ligands for selectivity for one or more metals; result is a resin that quickly recognizes and removes targeted metals from waste, remediation, and process streams. Eichrom`s Diphonix {reg_sign} resin is the first DMBP to be widely released as a commercial product; it is polystyrene based. Objective of this work is to synthesize commercial quantities of a silica-based ion exchange resin with the same or better metal ion selectivity, metal uptake kinetics, and acid stability as Diphonix. Feasibility was determined, however the process needs to be optimized. Studies at Eichrom and ANL of the performance of Diphonix resin over a broad range of HNO3 and HCl conditions and inorganic salt loadings are discussed together with the proposed method of incorporating similar characteristics into a silica-based resin. The new, silica-based resin functionalized with diphosphonic acid ligands can be used in environmental restoration and waste management situations involving processing of low-level, transuranic, and high-level radioactive wastes; it can also be used for processing liquid mixed waste including wastes contaminated with organic compounds.

Gula, M.; Harvey, J.

1996-12-31

186

Microscale Dehydration of Cyclohexanol Using a Macroreticular Cation Exchange Resin as Catalyst  

NASA Astrophysics Data System (ADS)

There are few experiments for the undergraduate laboratory involving ion exchange resins as catalysts. In this experiment, cyclohexanol is dehydrated to cyclohexene using Amberlyst 15 macroreticular resin as an acid catalyst. The procedure is carried out with partners, one student using phosphoric acid-sulfuric acid catalyst, the other student using the resin. Yields and ease of manipulation between the two options are compared.

Moeur, Harriet P.; Swatik, Sharon A.; Pinnell, Robert P.

1997-07-01

187

Effects of coupling agents on dynamic mechanical properties of aged and wet multi-functional epoxy resins cured with acid anhydrides and filled with pitch based carbon short fibers treated with coupling agents  

Microsoft Academic Search

Pitch-based carbon short fibers (PCF) as functional fillers were treated with five types of coupling agents (CA) and were filled with multi-functional epoxy resin (EP) cured with three types of acid anhydrides at 22.2 wt%. The influence of aging and wetting on the dynamic mechanical properties was studied by use of a non-resonant forced-vibration method. The samples were aged at

Muneaki Yamaguchi; Yuko Tanaka; Katsutoshi Tanaka

1998-01-01

188

Determination of hydrogen ion by ion chromatography (IC) with sulfonated cation-exchange resin as the stationary phase and aqueous EDTA (ethylenediamine-N,N,N?,N?-tetraacetic acid) solution as the mobile phase  

Microsoft Academic Search

An ion chromatographic (IC) method has been developed for determination of hydrogen ion (H+). It is based on the use of sulfonated cation-exchange resin as stationary phase, aqueous ethylenediamine-N,N,N?,N?-tetraacetic acid (dipotassium salt, EDTA-2K, written as K2H2Y) solution as mobile phase, and conductivity for detection. H+ was separated mainly by cation-exchange, but its elution was accelerated by the presence of EDTA.

Wenzhi Hu; Alexander Iles; Kiyoshi Hasebe; Hidenori Matsukami; Shunan Cao; Kazuhiko Tanaka

2001-01-01

189

Effect of configuration of amino acid moieties on adsorption of alanine and glycine peptides by a cation-exchange resin  

Microsoft Academic Search

1.A change in the configuration of the N-terminal amino acid moiety, or its replacement by glycine, in H-AlaAlaAla-OH(LLL) gives a greater difference in the retention times than does a change in the second and third moieties.2.A strict fulfillment is not observed of the assumption that for the higher peptides the changes in their retention times on a sulfonated cationite are

V. A. Tsyryapkin; V. A. Shirokov; V. M. Belikov

1974-01-01

190

A novel star-shaped poly(carboxylic acid) for resin-modified glass-ionomer restoratives.  

PubMed

We have developed a novel glass-ionomer cement (GIC) system composed of photo-curable star-shaped poly(acrylic acid-co-itaconic acid)s. These polyacids were synthesized via a chain-transfer radical polymerization using a newly synthesized multi-arm chain-transfer agent. The star-shaped polyacids showed significantly lower viscosities in water as compared to the linear polyacids. Due to the lower viscosities, the molecular weight (MW) of the polyacids can be significantly increased for enhancing the mechanical strengths while keeping the ease of mixing and handling. The effects of MW, GM-tethering ratio, P/L ratio, and aging on the compressive properties of the experimental cements were significant. The light-cured experimental cements showed significantly improved mechanical strengths i.e. 49% in yield strength, 41% in modulus, 25% in CS, 20% in DTS, and 36% in FS, higher than commercial Fuji II LC. After aging in water for 1 month, the compressive strength of the novel light-cured experimental cement reached 343?MPa, which was 34% and 42% higher than Fuji II and Fuji II LC, respectively. This one-month aged experimental cement was also 23% higher than itself after one day aging, indicating that aging in water can significantly enhance salt-bridge formation for this novel star-shaped polyacid-comprised GIC. PMID:24865692

Weng, Y; Howard, L; Xie, D

2014-07-01

191

Effect of Ascorbic Acid on Shear Bond Strength of Orthodontic Brackets Bonded with Resin-modified Glass-ionomer Cement to Bleached Teeth  

PubMed Central

Background and aims Bleaching can considerably reduce shear bond strength (SBS) of orthodontic brackets bonded with composite adhesives. Application of antioxidants is a method to reverse the negative effect of bleaching on composite-to-enamel bond. However, the efficacy of antioxidants in increasing the SBS of brackets bonded using resin-modified glass-ionomer cement (RMGIC) has not been studied, which was the aim of this study. Materials and methods Fifty freshly extracted human maxillary first premolars were bleached with 35% hydrogen peroxide (Pola Office Bleaching, SDI). Sodium ascorbate 10% was applied to the experimental specimens (n=25). All the specimens were etched with 37% phosphoric acid (Ivoclar/Vivadent) and bonded using RMGIC (Fuji Ortho LC, GC). The specimens were subjected to incubation (37°C, 24h) and thermocycling (1000 cycles, 5-55°C, dwell time = 1 min). The SBS was measured at 0.5 mm/min debonding crosshead speed. The adhesive remnant index (ARI) was scored under ×10 magni-fication. Data were analyzed using Mann-Whitney U test, one- and independent-samples t-test, and Fisher’sexact test (?=0.05). Results The mean SBS of experimental and control groups were 11.97 ± 4.49 and 7.7 ± 3.19 MPa, respectively. The dif-ference was statistically significant (P=0.000 by t-test). SBS of both control (P=0.014) and experimental (P=0.000) groups were significantly higher than the minimum acceptable SBS of 6 MPa, according to one-sample t-test. Conclusion Application of ascorbic acid can guarantee a strong bond when RMGIC is to be used. However, RMGIC might tolerate the negative effect of bleaching with minimum SA treatments (or perhaps without treatments), which de-serves further studies.

Khosravanifard, Behnam; Rakhshan, Vahid; Araghi, Solmaz; Parhiz, Hadi

2012-01-01

192

Resin composition and articles molded therefrom  

US Patent & Trademark Office Database

A resin composition having a high refractive index and low dispersion characteristics including a carbonate residue, a phosphonic acid residue and a dihydric phenol residue, wherein the mol fractions of the phosphonic acid residue and the carbonate residue satisfy wherein (a) represents the number of moles of the phosphonic acid residues, and (b) represents the number of moles of the carbonate residues.

2004-06-15

193

K Basin Sludge Conditioning Process Testing Project Results from Test 4, ''Acid Digestion of Mixed-Bed Ion Exchange Resin''  

SciTech Connect

Approximately 73 m{sup 3} of heterogeneous solid material, ''sludge,'' (upper bound estimate, Packer 1997) have accumulated at the bottom of the K Basins in the 100 K Area of the Hanford Site. This sludge is a mixture of spent fuel element corrosion products, ion exchange materials (organic and inorganic), graphite-based gasket materials, iron and aluminum metal corrosion products, sand, and debris (Makenas et al. 1996, 1997). In addition, small amounts of polychlorinated biphenyls (PCBs) have been found. Ultimately, it is planned to transfer the K Basins sludge to the Hanford double shell tanks (DSTs). The Hanford Spent Nuclear Fuel (HSNF) project has conducted a number of evaluations to examine technology and processing alternatives to pretreat K Basin sludge to meet storage and disposal requirements. From these evaluations, chemical pretreatment has been selected to address criticality issues, reactivity, and the destruction or removal of PCBs before the K Basin sludge can be transferred to the DSTs. Chemical pretreatment, referred to as the K Basin sludge conditioning process, includes nitric acid dissolution of the sludge (with removal of acid insoluble solids), neutrons absorber addition, neutralization, and reprecipitation. Laboratory testing is being conducted by the Pacific Northwest National Laboratory (PNNL) to provide data necessary to develop the sludge conditioning process.

Pool, K.H.; Delegard, C.H.; Schmidt, A.J.; Thornton, B.M.; Silvers, K.L.

1999-04-02

194

Development of PBBI Laminating Resin.  

National Technical Information Service (NTIS)

PBBI resin formulary studies were performed in order to increase resin toughness and to decrease resin shrinkage while maintaining improved moisture resistance over state of the art, 177 C (350 F) service epoxy resins. The most promising approach was iden...

R. W. Vaughan R. A. Buyny

1979-01-01

195

Comparison of the irritation potentials of Boswellia serrata gum resin and of acetyl-11-keto-beta-boswellic acid by in vitro cytotoxicity tests on human skin-derived cell lines.  

PubMed

Indian frankincense is a gum resin from Boswellia serrata of Burseraceae used in Ayurveda and Western medicine for the antinflammatory effects of boswellic acids, particularly 3-O-acetyl-11-keto-beta-boswellic acid (AKBA). We evaluated in vitro cytotoxicities of B. serrata extract and AKBA on differentiated and undifferentiated keratinocytes (HaCaT and NCTC 2544), and foetal dermal fibroblasts (HFFF2), using neutral red uptake (NRU), MTT, and DNA assays. Comparison between NRU and MTT, and between the extract and AKBA, suggested a relatively higher toxicity of both substances on lysosomes respect to mitochondria. Extract cytotoxicity on lysosomes was higher in NCTC and HFFF2 than on the more differentiated HaCaT. DNA assay showed low extract inhibition on HFFF2 proliferation, possibly due to lower growth rate, and a stronger effect on NCTC than on HaCaT, possibly related to higher proapoptotic effect on the less differentiated NCTC, as also suggested by higher AKBA toxicity on NCTC than on HaCaT. In general, gum resin and AKBA toxicities were slightly lower or higher than that of the reference compound SDS. Our in vitro model allowed to compare the sensitivities of different human skin cells to B. serrata, and indicated that the gum resin and AKBA exert moderate to low toxicity on the skin. PMID:18304763

Burlando, Bruno; Parodi, Alessandro; Volante, Andrea; Bassi, Anna Maria

2008-03-15

196

Biological Ion Exchanger Resins  

PubMed Central

The cell is presented as a biological ion exchanger resin. The similarities between ion accumulating cells and ion exchanger resins are correlated. The kinetic characteristics of biological ion exchange are shown to be amenable to analysis by a model commonly used for ion exchanger resins. The theories of ion exchange equilibria currently in use with ion exchanger resins are reviewed with their suitability for adaptation to biological ion exchange in mind. ImagesFIGURE 1

Damadian, Raymond

1971-01-01

197

Trimerization of isobutene over cation exchange resins: Effect of physical properties of the resins and reaction conditions  

Microsoft Academic Search

Oligomerization of isobutene has been investigated using several cation exchange resins in order to produce triisobutenes that are useful feedstock for heavy alkylates and neo-acids. Trimers selectivity increases with increasing isobutene conversion. High isobutene conversion is obtained at high temperature and low space velocity by using macroporous cation exchange resins that have high concentration of sulfonic acid groups. Under selected

Ji Woong Yoon; Jong-San Chang; Hee-Du Lee; Tae-Jin Kim; Sung Hwa Jhung

2006-01-01

198

Resin-Powder Dispenser  

NASA Technical Reports Server (NTRS)

Resin-powder dispenser used at NASA's Langley Research Center for processing of composite-material prepregs. Dispenser evenly distributes powder (resin polymer and other matrix materials in powder form) onto wet uncured prepregs. Provides versatility in distribution of solid resin in prepreg operation. Used wherever there is requirement for even, continuous distribution of small amount of powder.

Standfield, Clarence E.

1994-01-01

199

Sorption of organics from aqueous solution onto polymeric resins  

SciTech Connect

The uptake of phenol, toluene, chlorobenzene, and benzoic acid by several polymeric resins and activated carbon was investigated experimentally. Presentation of the sorption data in terms of the number of sorbed monolayers and fractional pore volume filled indicated that, for the polymeric resins, solute uptake cannot be viewed as only a surface adsorption phenomenon. It is suggested that the aqueous phase uptake of phenol, toluene, chlorobenzene, and benzoic acid by the polymeric resins is attributable, in part, to solute absorption. The present study also suggests that solute uptake is affected by the swelling of some of the polymeric resins in water.

Gusler, G.M.; Browne, T.E.; Cohen, Y. (Univ. of California, Los Angeles, CA (United States). Dept. of Chemical Engineering)

1993-11-01

200

Thermal stability of boron-containing phenol formaldehyde resin  

Microsoft Academic Search

The boron-containing phenol-formaldehyde resin derived from phenol, formaldehyde and boric acid was synthesized. The mechanisms of synthesis and curing reactions were investigated by infrared spectroscopy and chemical analysis. The kinetics of thermal degradation and thermal stability were determined by thermal analysis. The results show that the resin has higher heat oxidation resistance than common phenol-formaldehyde resins. In addition, the fiberglass-reinforced

Jungang Gao; Yanfang Liu; Liting Yang

1999-01-01

201

Use of Cation Exchange Resins for Production of UâOâ Suitable for the Al-UâOâ Powder Metallurgy Process  

Microsoft Academic Search

This report describes the production of UâOâ powders from three types of cation exchange resins: Dowex 50W, a strong acid, sulfonate resin; AG MP-50, a macroporous form of sulfonate resin; and Bio-Rex 70, a weak acid, carboxylic resin.

2001-01-01

202

Evaluation of Elution Parameters for Cesium Ion Exchange Resins  

SciTech Connect

Cesium ion exchange is one of the planned processes for treating and disposing of waste at the U.S. Department of Energy Hanford Site. Radioactive supernatant liquids from the waste tanks will undergo ultrafiltration, followed by cesium ion exchange using a regenerable organic ion exchange resin. Two resins, SuperLig?644 and a Resorcinol-formaldehyde resin are being evaluated for cesium removal and cesium elution characteristics. The main purpose of this study is to optimize the cesium elution to provide a resin which after undergoing elution would meet the U.S. Department of Energy/Office of River Protection Project-Waste Treatment Plant processing and resin disposal criteria. Columns of each resin type were loaded to greater or equal to 90% breakthrough with a Hanford waste stimulant and eluted with nitric acid. The temperature, flow rate and nitric acid concentration were varied to determine the optimal elution conditions. Temperature and eluant flow rate were the most important elution parameters. As would be predicted based upon kinetic consideration alone, decreasing the eluant flow rate and increasing the temperature provided the optimal elution conditions. Varying the nitric acid concentration did not have a significant effect on the elution; however, elutions performed using both high acid concentration (1M) and elevated temperature (45 C) resulted in resin degradation, causing gas generation and resin bed disruption.

Burgeson, Ingrid E.; Deschane, Jaquetta R.; Cook, Bryan J.; Blanchard, David L.; Weier, Dennis R.

2006-08-28

203

21 CFR 175.300 - Resinous and polymeric coatings.  

Code of Federal Regulations, 2011 CFR

... (d ) Rosin salts: Calcium resinate...Phenolic resins as the basic polymer formed by...Elastomers, as the basic polymer: Butadiene-acrylonitrile...acid, to form the salt listed in paragraph...Zirconium. (b ) Salts: Caprate. Caprylate...minimum), as the basic polymer....

2011-04-01

204

Advanced Thermoplastic Resins, Phase 1.  

National Technical Information Service (NTIS)

Eight thermoplastic polyimide resin systems were evaluated as composite matrix materials. Two resins were selected for more extensive mechanical testing and both were versions of LaRC-TPI (Langley Research Center - Thermoplastic Polyimide). One resin was ...

C. L. Hendricks S. G. Hill A. Falcone N. T. Gerken

1991-01-01

205

Cation exchange resins from chemically modified poly(vinyl chloride)  

Microsoft Academic Search

Poly(vinyl chloride) has been modified chemically to a cation exchange resin by halogen displacement reactions with phenol sulfonic acid, bisphenol-A sulfonic acid and phenolpthalein sulfonic acid. Ion-exchange capacity, salt-splitting capacity and pH-titration characteristics of these resins have been evaluated. pH-titration behaviour of these resins is consistent with that of a polyfunctional cation-exchanger having pK1=2 and pK2=9–10 corresponding to -SO3H and

Subrata Moitra; Mukul Biswas

1987-01-01

206

Improved well stimulation with resin-coated proppants  

SciTech Connect

Resin-coated proppants improve well stimulation results by preventing flowback, or fracture evacuation, near the wellbore, a phenomenon that effectively ''decouples'' the wellbore and the productive formation. In addition, the deformable coating protects the resin-coated proppants from crushing and helps resist embedment in softer formations. The tough coating is chemically inert in crude oils, brines, and most acids. The resin-coated materials work best under actual downhole conditions since the closure stress and temperature help lock the materials in the fracture for the life of the well. This paper reviews case histories from four wells in which resin-coated proppants were used. In addition, simple lab tests of the resin-coated proppants in an API crush cell confirm their excellent properties and potential. Together, these results show the need for resin-coated proppants in many types of wells. In many ways they act as ''ideal'' proppants that can be economically justified over uncoated proppants.

Sinclair, A.R.; Graham, J.W.; Sinclair, C.P.

1983-02-01

207

IRRADIATED PETROLEUM RESINS  

Microsoft Academic Search

A method for improving the properties of polymeric material produced by ; the Friedel-Crafts polymerization of light, cracked petroleum fractions is ; presented. The petroleum resins are mixed with a divinyl aromatic and irradiated ; at a dose rate of at least 0.1 equivalent Mr\\/hr until at least 1\\/2 equivalent Mr ; is absorbed. Resinous solids are obtained that have

J. E. Shewmaker; J. F. Nelson

1963-01-01

208

Incombustible resin composition  

NASA Technical Reports Server (NTRS)

Incombustible resin compositions composed of aromatic compounds were obtained through (1) combustion polymer material and (2) bisphenol A or halogenated bisphenol A and bisphenol A diglycidl ether or halogenated bisphenol A diglycidyl ether. The aromatic compound is an adduct of bifunctional phenols and bifunctional epoxy resins.

Akima, T.

1982-01-01

209

Delayed cure bismaleimide resins  

DOEpatents

Prior art polybismaleimides begin to polymerize at or just above the melting point of the monomer. This patent describes new bismaleimide resins which have an increased pot life and provide longer time periods in which the monomer remains fluid. The resins can be polymerized into molded articles with a high uniformity of properties. (DLC)

Not Available

1982-08-12

210

A new configuration of membrane stack for retrieval of nickel absorbed in resins  

Microsoft Academic Search

A new configuration integrated ion exchange effect with both electro-migration and electrochemical reaction in a single cell was developed to effectively retrieve metal ions from simulated wastewater using ion exchange resins without additive chemicals. By simply assembling cation exchange resins and anion exchange resins separated by homogeneous membranes, we found that the system will always be acidic in the concentrate

CHEN Xue-fen; WU Zu-cheng

211

Lignin from waste black liquor 3-treated lignin in phenol formaldehyde resin  

Microsoft Academic Search

Bagasse and rice straw lignins undergo different treatments, e.g. acid hydrolysis, oxidation with hydrogen peroxide and thermal treatment, before being used as a partial replacement for phenol in phenol formaldehyde resin. These treatments improved the resin formation properties of the lignin. The effect of these treatments on the improvement of the properties of the resin produced has the following sequence:

A. M. A. Nada; M. A. Yousef; K. A. Shaffei; A. Salah

2000-01-01

212

In situ derivatisation and extraction of volatile fatty acids entrapped on anion-exchange resin from aqueous solutions and urine as a test matrix using pentafluorobenzyl bromide in supercritical carbon dioxide.  

PubMed

The simultaneous extraction and derivatisation of anion-exchange resin-trapped volatile fatty acids (C2-C5) as their pentafluorobenzyl esters has successfully been performed under CO2 supercritical fluid extraction conditions. Volatile fatty acid standards of acetic, propionic and n-butyric acids (at 20 and 100 ppm) as their ester derivatives were recovered at 78.0-101.5% (C.V. 3.5-7.5%, n=6 and 7). Likewise, acrylic acid recoveries were 57.0-61.0% (C.V. 5.5-5.6%, n=6 and 7). This methodology was applied to the quantitation of acetic, propionic, n-butyric and n-valeric acids in spiked urine as a test matrix. Initial clean-up of phosphate and sulfate in the urine was required prior to anion-exchange application and this was achieved by barium salt precipitation. Recoveries ranged from 36 to 66.5% (C.V. 5.9-14.4%, n=9 and 6). PMID:9234843

Cummins, M T; Wells, R J

1997-06-20

213

Radiation testing of organic ion exchange resins  

SciTech Connect

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated with a {sup 60}Co source to a total absorbed dose of 10{sup 9} R over a period of 5 months in a static (no flow) and a flowing configuration with neutralized current acid waste (NCAW) simulant as a feed. Based on a maximum concentration of {sup 137}Cs on the resin that would result from processing NCAW, this dose represents an operational period of at least 150 days for the RF resin and at least 1260 days for the CS-100 resin. Gas generation in the static experiment was continuously monitored and G values (molecules of gas per 100 eV) were determined for each species. Resin samples were obtained periodically and the equilibrium behavior of the resins was assessed by determining the distribution coefficients (K{sub d}s). Structural information was also obtained by {sup 13}C cross polarization magic angle (CPMAS) nuclear magnetic resonance (NMR) spectrometry and Fourier Transform Infrared (FTIR) spectroscopy so that changes to the chemical structure could be correlated with changes in K{sub d}.

Carlson, C.D.; Bray, L.A.; Bryan, S.A. [and others

1995-09-01

214

Ethylated Urea - Ether - Modified Urea - Formaldehyde Resins, Part I: Structural and Physicochemical Properties  

Microsoft Academic Search

First, phenol - formaldehyde (PF) and urea - formaldehyde (UFII) resins were separately conventionally prepared in our laboratory. Also, UF resin synthesized from the acid modified synthesis procedure was synthesized in a purely acid medium of pH 1.0, FU molar ratio of 1.0 and at 50oC (one-stage acid modified-synthesis procedure). Subsequently, the UF resin II was modified during synthesis by

Mathew Obichukwu EDOGA

215

Development of resins for composites by resin transfer molding  

NASA Technical Reports Server (NTRS)

Designed to cover a wide range of resin technology and to meet the near-term and long-term needs of the aircraft industry, this research has three objectives: to produce resin transfer molding (RES) resins with improved processability, to produce prepreg systems with high toughness and service temperature, and to produce new resin systems. Progress on reaching the objectives is reported.

Woo, Edmund P.; Puckett, Paul M.; Maynard, Shawn J.

1991-01-01

216

Resin catalysts and method of preparation  

DOEpatents

Heat stabilized catalyst compositions are prepared from nuclear sulfonic acid, for example, macroporous crosslinked polyvinyl aromatic compounds containing sulfonic acid groups are neutralized with a metal of Al, Fe, Zn, Cu, Ni, ions or mixtures and alkali, alkaline earth metals or ammonium ions by contacting the resin containing the sulfonic acid with aqueous solutions of the metals salts and alkali, alkaline earth metal or ammonium salts. The catalysts have at least 50% of the sulfonic acid groups neutralized with metal ions and the balance of the sulfonic acid groups neutralized with alkali, alkaline earth ions or ammonium ions.

Smith, L.A. Jr.

1986-12-16

217

Resin catalysts and method of preparation  

DOEpatents

Heat stabilized catalyst compositions are prepared from nuclear sulfonic acid, for example, macroporous crosslinked polyvinyl aromatic compounds containing sulfonic acid groups are neutralized with a metal of Al, Fe, Zn, Cu, Ni, ions or mixtures and alkali, alkaline earth metals or ammonium ions by contacting the resin containing the sulfonic acid with aqueous solutions of the metals salts and alkali, alkaline earth metal or ammonium salts. The catalysts have at least 50% of the sulfonic acid groups neutralized with metal ions and the balance of the sulfonic acid groups neutralized with alkali, alkaline earth ions or ammonium ions.

Smith, Jr., Lawrence A. (P.O. Box 34687, Houston, TX 77243)

1986-01-01

218

Epoxy Schiff Base Resin Manufacturing Method.  

National Technical Information Service (NTIS)

A manufacturing method for epoxy Schiff base resin is described, characterized by the fact that at least one or more types of dicarboxylic acid having an azomethyne compound represented by the general expression: HOOC-R sub 1 -N=HC-R sub 2 -COOH, HOOC-R s...

T. Kimura

1986-01-01

219

Development of metal-resin composite restorative material. Part 4. Flexural strength and flexural modulus of metal-resin composite using Ag-In alloy particles as filler.  

PubMed

The flexural strength and flexural modulus of an experimental metal-resin composite, which used Ag-In alloy particle as the filler, were evaluated. The effect of acid treatment and heat treatment on the Ag-In alloy particle was investigated. The flexural strength of the experimental metal-resin composites ranged from 65.5 MPa to 91.0 MPa. The flexural strength of the metal-resin composite increased with the temperature of the heat treatment until 350 degrees C, but its effect varied with the concentrations of HCl of the acid treatment. A metal-resin composite, which used acid-treated and 350 degrees C heat-treated Ag-In alloy fillers, matched the requirement of strength of ISO 4049. The average of flexural modulus of the experimental metal-resin composite was 9.1 GPa. The flexural modulus of the metal-resin composite did not vary with the treatment conditions of the metal filler. The flexural modulus of a metal-resin composite, which used Ag-In alloy particle as the filler, was lower than that of Ag-Sn alloy metal-resin composite, which was reported previously. However, the flexural strength of the Ag-In alloy metal-resin composite was similar to that of Ag-Sn alloy metal-resin composite. We can control a flexural modulus of a metal-resin composite without decreasing flexural strength by choosing filler materials. PMID:12238786

Kakuta, Kiyoshi; Urapepon, Somchai; Miyagawa, Yukio; Ogura, Hideo; Yamanaka, Masahiko; Suchatlampong, Chatcharee; Rittapai, Apiwat

2002-06-01

220

Binding Studies on Resins Imprinted with (S)-naproxen.  

National Technical Information Service (NTIS)

Resins were prepared in a free-radical polymerization of 4- vinylpyridine and ethylene glycol dimethacrylate in the presence of (S)-(+)-6- methoxy-alpha-methyl-2- naphtaleneacetic acid ((S)-naproxen). Initially (S)- naproxen, the imprinted molecule templa...

R. A. Orwoll Y. Hu

2002-01-01

221

Biocidal quaternary ammonium resin  

NASA Technical Reports Server (NTRS)

Activated carbon (charcoal) and polymeric resin sorbents are widely used in the filtration and treatment of drinking water, mainly to remove dissolved organic and inorganic impurities and to improve the taste. Earlier hopes that activated carbon might "disinfect' water proved to be unfounded. The feasibility of protecting against microbial infestation in charcoal and resin beds such as those to be incorporated into total water reuse systems in spacecraft was investigated. The biocidal effect of IPCD (insoluable polymeric contact disinfectants) in combination with a representative charcoal was assessed. The ion exchange resins (IPCD) were shown to adequately protect charcoal and ion exchange beds.

Janauer, G. E.

1983-01-01

222

Separation of organic ion exchange resins from sludge -- engineering study  

SciTech Connect

This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

Duncan, J.B.

1998-08-25

223

Commercial Flame Retardancy of Unsaturated Polyester and Vinyl Resins: Review  

Microsoft Academic Search

Chlorendic acid-based and tetrabromophthalate polyesters are major flame-retardant polyester resins, often used with antimony trioxide. For translucency, colloidal antimony pentoxide is preferred. Brominated diols are occasionally used. In the vinyl ester group, the adducts of acrylic or methacrylic acid with the diglycidyl ether of tetrabromobisphenol A are prodominant, and the styrene-cured resins often have advantageous physical properties and hydrolytic stability.

Edward D. Weil; Sergei V. Levchik

2004-01-01

224

Benzonorbornadiene end caps for PMR resins  

NASA Technical Reports Server (NTRS)

Several ortho-disubstituted benzonorbornadiene derivatives are described. These molecules contain acid, ester, or anhydride functionality permitting their use as end caps in PMR (polymerization of monomer reactants) polyimide systems. The replacement of the currently used norbornenyl end caps with benzonorbornadienyl end caps affords resins of increased aromatic content. It also allows evaluation of some mechanistic aspects of PMR cross-linking. Initial testing of N-phenylimide model compounds and of actual resin formulations using the benzonorbornadienyl end cap reveals that they undergo efficient thermal crosslinking to give oligomers with physical properties and thermal stability comparable to commercial norbornene-end-capped PMR systems.

Panigot, Michael J.; Waters, John F.; Varde, Uday; Sutter, James K.; Sukenik, Chaim N.

1992-01-01

225

Branched polymeric media: boron-chelating resins from hyperbranched polyethylenimine.  

PubMed

Extraction of boron from aqueous solutions using selective resins is important in a variety of applications including desalination, ultrapure water production, and nuclear power generation. Today's commercial boron-selective resins are exclusively prepared by functionalization of styrene-divinylbenzene (STY-DVB) beads with N-methylglucamine to produce resins with boron-chelating groups. However, such boron-selective resins have a limited binding capacity with a maximum free base content of 0.7 eq/L, which corresponds to a sorption capacity of 1.16 ± 0.03 mMol/g in aqueous solutions with equilibrium boron concentration of ?70 mM. In this article, we describe the synthesis and characterization of a new resin that can selectively extract boron from aqueous solutions. We show that branched polyethylenimine (PEI) beads obtained from an inverse suspension process can be reacted with glucono-1,5-D-lactone to afford a resin consisting of spherical beads with high density of boron-chelating groups. This resin has a sorption capacity of 1.93 ± 0.04 mMol/g in aqueous solution with equilibrium boron concentration of ?70 mM, which is 66% percent larger than that of standard commercial STY-DVB resins. Our new boron-selective resin also shows excellent regeneration efficiency using a standard acid wash with a 1.0 M HCl solution followed by neutralization with a 0.1 M NaOH solution. PMID:22827255

Mishra, Himanshu; Yu, Changjun; Chen, Dennis P; Goddard, William A; Dalleska, Nathan F; Hoffmann, Michael R; Diallo, Mamadou S

2012-08-21

226

Dilatometry on Thermoset Resins.  

National Technical Information Service (NTIS)

A simple capillary and bulb mercury dilatometer designed for making specific volume measurements on thermoset resin systems during the curing reaction and as a function of temperature is described. The design, calibration, operation, data treatment and er...

A. W. Snow J. P. Armistead

1991-01-01

227

Thermally stable laminating resins  

NASA Technical Reports Server (NTRS)

Improved thermally stable laminating resins were developed based on the addition-type pyrolytic polymerization. Detailed monomer and polymer synthesis and characterization studies identified formulations which facilitate press molding processing and autoclave fabrication of glass and graphite fiber reinforced composites. A specific resin formulation, termed P10P was utilized to prepare a Courtaulds HMS reinforced simulated airfoil demonstration part by an autoclave molding process.

Jones, R. J.; Vaughan, R. W.; Burns, E. A.

1972-01-01

228

Conversion of ion exchange resin to various functional resins and the application in the field of pharmaceutical sciences  

NASA Astrophysics Data System (ADS)

Ion exchange resins are widely used for separating ions in the solution, desalination, removal of impurities, and etc. Giving a new function to these ion exchange resins enables the application in more various fields. Until now, we carried out the research work about the following 5 project.: (1) Conversion of ion exchange resins into selective adsorbents by using low molecular reagents, which possess capabilities of a selective reaction with target ions, ion exchange reaction with the ion exchange resin and strong physical adsorption to the ion exchange resin. (2) Synthesis of resins for ion exchange high performance liquid chromatography (IEHPLC) and the analysis of biomaterials. (3) Development of insoluble macromolecular Sn(II) complex based on the aminophosphonic acid type ion exchange resin and its application to the 99mTc labeling of proteins. (4) Development of a new 68Ge-68Ga generator using N-methylglucamine type organic polymer as the adsorbent for 68Ge and production of 68Ga for PET. (5) Preparation of an ion-exchangeable polymer bead wrapped with bilayer membrane structures. In this paper, the application of various functional resins prepared based on ion exchange resin in the field of pharmaceutical sciences has been summarized.

Nakayama, Morio

229

Improved resin infiltration of natural caries lesions.  

PubMed

In artificial lesions, improved penetration and the caries-inhibiting properties of infiltrating resins could be observed with increasing penetration coefficients (PCs). The aim of the present study was to compare the penetration abilities of an experimental 'infiltrant' into natural lesions with those of an adhesive in vitro. Extracted human molars and premolars showing proximal white spots were cut across the lesions perpendicular to the surface. Corresponding lesion halves were etched for 120 sec with 15% hydrochloric acid gel and were subsequently treated with either an adhesive (PC: 31 cm/sec) or an infiltrant (PC: 273 cm/sec). Specimens were observed by confocal microscopy and transverse microradiography. Penetration depths of the adhesive were significantly lower compared with those of the infiltrant (p < 0.001; Wilcoxon). It can be concluded that resins with higher PCs (infiltrants) show superior ability to penetrate natural lesions compared with resins with lower PCs. PMID:19029077

Meyer-Lueckel, H; Paris, S

2008-12-01

230

Use of Cation Exchange Resins for Production of U{sub 3}O{sub 8} Suitable for the Al-U{sub 3}O{sub 8} Powder Metallurgy Process  

SciTech Connect

This report describes the production of U{sub 3}O{sub 8} powders from three types of cation exchange resins: Dowex 50W, a strong acid, sulfonate resin; AG MP-50, a macroporous form of sulfonate resin; and Bio-Rex 70, a weak acid, carboxylic resin.

Mosley, W.C.

2001-09-17

231

40 CFR 414.50 - Applicability; description of the thermosetting resins subcategory.  

Code of Federal Regulations, 2013 CFR

...Ketone-Formaldehyde Resins *Melamine Resins *Phenolic Resins *Polyacetal Resins Polyacrylamide *Polyurethane Prepolymers *Polyurethane Resins *Urea Formaldehyde Resins *Urea Resins [52 FR 42568, Nov. 5, 1987, as amended...

2013-07-01

232

Characterization of resins in alternative fuel mixtures  

SciTech Connect

Resins is a class of compounds believed to play an important role in the conversion processes of coal and coal-related material into oils. Methods currently used to isolate this fraction, generally lack reproducibility and yield impure and strongly overlapping fractions which do not reflect the actual group type distribution in the liquid fuel. A separation method based on liquid column chromatography was developed, which divides liquid fuels into eight distinct and minimally overlapping chemical classes: five non-polar (saturated, mono-, di-, tri-, and polynuclear aromatics), one intermediate polar (resins), and two polar (asphaltenes and asphaltols) fractions. Chemical characterization of resins fractions, derived from two alternative fuels (coal-derived liquid and sugarcane bagasse), was achieved by first subjecting them to acid-base-neutral separation, followed by analysis of each subfraction by GC/MS. Identification of the eluted components was carried out utilizing a library search system, by comparing retention time (indices) of 150 model compounds believed to exist in liquid fuels, on two fused silica capillary columns (Carbowax 20 M and Se-54), and by mass spectral interpretation. GC/MS results indicate that resins are mainly composed of weakly acidic (phenols, indanols, naphthols), mildly basic (benzoquinolines, choroanilines, etc.), neutral-nitrogen (indoles and carbazoles), and oxygen (carbonyl) compounds, and are free of hydrocarbons.

Karam, H.S.

1986-01-01

233

Phenoxy Resins Containing Pendent Ethynyl Groups and Cured Resins Therefrom.  

National Technical Information Service (NTIS)

Phenoxy resins containing pendent ethynyl groups, the process for preparing the same, and the cured resin products obtained therefrom, are discussed. Upon the application of heat, the ethynyl groups react to provide branching and crosslinking. The cure te...

P. M. Hergenrother

1984-01-01

234

Ageing behaviour and analytical characterization of the Jatobá resin collected from Hymenaea stigonocarpa Mart.  

NASA Astrophysics Data System (ADS)

This paper reports the results of an analytical study to characterize the trunk resin collected from the Hymenaea stigonocarpa Mart. species from the region of Minas Gerais (Brazil), popularly known as Jatobá resin. Hymenaea resins are reported to have been used in artistic applications such as protective varnishes in polychromed sculptures and paintings. Therefore, the identification of the main chemical changes that take place in the resin when it is prepared as a thin film exposed to atmospheric effects have been considered herein. Changes due to the degradation effect of light have been studied on a series of specimens prepared as a thin films and subjected to accelerated UV light ageing. The results based on GC-MS, THM-Py-GC-MS analyses, and on-line trimethylsilylation Py-GC-MS using hexamethyldislylazane as a derivatization reagent, have been compared. The study shows that eperuic acid and its [Delta]7 and [Delta]8 isomers, together with copalic acid, are the major components of the studied resin. Other compounds such as kolavenic acid, iso-ozic acid and epi-pinifolic acid are also present in this resin as minor components. This composition differs from those of resins obtained from other species of the Hymenaea genus growing in this Amazonian region. UV light ageing of the Jatobá resin prepared as a thin film results in the appearance of a new isomer of eperuic acid. Some changes in the relative content of the major components present in the resin have also been observed after ageing.

Doménech-Carbó, María Teresa; de La Cruz-Cañizares, Juana; Osete-Cortina, Laura; Doménech-Carbó, Antonio; David, Helena

2009-07-01

235

High-performance bismaleimide resin for resin film infusion  

Microsoft Academic Search

A novel high-performance resin system, suitable for resin film infusion (RFI) process, has been developed. It was prepared from N,N?-diphenylbismaleimide, o,o?-diallylbisphenol A, and polyethylsulfone. The resin and its composite, reinforced by a glass fiber cloth, were prepared and characterized in detail. The results showed that the prepared resin film is stable at room temperature, the infusion temperature is 120°C, and

Guozheng Liang; Dong Wang

2002-01-01

236

Method for regenerating ion exchange resin.  

National Technical Information Service (NTIS)

This invention is comprised of a method for regenerating ion exchange resin consisting of a mixed resin containing granular cation exchange resin and anion exchange resin contaminated during condensation treatment in steam power generating plants, charact...

M. Ogihara, K. Ichikawa, T. Idemizu

1991-01-01

237

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

Techniques were developed that provided thermo-oxidatively stable A-type polyimide/graphite fiber composites using the approach of in situ polymerization of monomeric reactants directly on reinforcing fibers, rather than employing separately prepared prepolymer varnish. This was accomplished by simply mixing methylene dianiline and two ester-acids and applying this solution to the fibers for subsequent molding. Five different formulated molecular weight resins were examined, and an optimized die molding procedure established for the 1500 formulated molecular weight system. Extensive ultrasonic inspection of composites was successfully utilized as a technique for monitoring laminate quality. Composite mechanical property studies were conducted with this polyimide resin at room temperature and after various time exposures in a thermo-oxidative environment at 561 K (550 F), 589 K (600 F) and 617 K (650 F). It was determined that such composites have a long term life in the temperature range of 561 K to 589 K. The final phase involved the fabrication and evaluation of a series of demonstration airfoil specimens.

Cavano, P. J.

1974-01-01

238

Use of unconventional oils in surface coatings: blends of alkyd resins with epoxy esters  

Microsoft Academic Search

The alkyd resin of short oil length with low acid value was modified with novolac-based epoxy esters, prepared by using tobacco seed oil fatty acids. The prepared blends were cured using an aliphatic amine as curing agent. The films of cured resins were applied over various panels and their film characteristics were studied. It was found that the scratch hardness

Madhu Bajpai; Sunita Seth

2000-01-01

239

Method for removing contaminants from plastic resin  

DOEpatents

A resin recycling method that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The method includes receiving the resin in container form. The containers are then ground into resin particles. The particles are exposed to a solvent, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. After separating the particles and the resin, a solvent removing agent is used to remove any residual solvent remaining on the resin particles after separation.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-12-09

240

Graphite Fiber Reinforced Thermoplastic Resins.  

National Technical Information Service (NTIS)

Mechanical properties of neat resin samples and graphite fiber reinforced samples of thermoplastic resins were characterized with particular emphasis directed to the effects of environmental exposure (humidity, temperature and ultraviolet radiation). Tens...

R. C. Novak

1975-01-01

241

The effects of ionizing radiation on Reillex trademark HPQ, a new macroporous polyvinylpyridine resin, and on four conventional polystyrene anion exchange resins  

SciTech Connect

This study compares the effects of ionizing radiation on Reillex{trademark} HPQ, a recently available macroporous copolymer of 1-methyl-4-vinylpyridine/divinylbenzene, and on four conventional strong-base polystyrene anion exchange resins. The polystyrene resins investigated included one gel type, Dowex{trademark} 1 {times} 4, and three macroporous resins: Dow{trademark} MSA-1, Amberlite{trademark} IRA-900, and Lewatit{trademark} MP-500-FK. Each resin, in 7 M nitric acid, was subjected to seven different levels of {sup 60}Co gamma radiation ranging from 100 to 1000 megarads. Irradiated resins were measured for changes in dry weight, wet volume, chloride and Pu(IV) exchange capacities, and thermal stability. In separate experiments, each resin was subjected to approximately 340 megarads of in situ alpha particles from sorbed plutonium. Resin damage from alpha particles was less than half that caused by gamma rays, which may be a consequence of different production rates of radiolytic nitrite and nitro radicals in the two systems. Reillex{trademark} HPQ resin provided the greatest radiation stability, whereas Lewatit{trademark} MP-500-FK was the least stable of the resins tested. Thermogravimetric analyses of dry, nitrate-form resin revealed that dry Reillex{trademark} HPQ resin offered the best thermal stability for absorbed gamma doses to 370 megarads, but the worst thermal stability after exposures of 550 megarads or more. 25 refs., 11 figs., 13 tabs.

Marsh, S.F.

1990-11-01

242

Cationic resins prepared by radiation-induced graft copolymerization  

NASA Astrophysics Data System (ADS)

Poly(acrylamide-acrylic acid) resin P(PAM-AA) was prepared by gamma radiation-initiated grafting copolymerization of acrylic acid (AA) on polyacrylamide (PAM) by addition of Mohr's salt as an inhibitor for homopolymerization. The polymerization was studied at different absorbed doses, polymor/monomer ratios and the monomer concentrations. The grafting percentage increases by increasing the dose and the monomer concentration and decreases by increasing polymer/monomer ratio. There is no significant change in the swelling degree of the obtained resin. It was found that the capacity of the resins towards Cu 2+ increases with increasing the monomer concentration and decreases by increasing the polymer/monomer ratio. The capacity of the resin was found to be constant at all doses.

Siyam, T.; Youssef, H. A.

1999-07-01

243

Production of petroleum polymer resins  

Microsoft Academic Search

In other countries, petroleum polymer resins are being used successfully in large volumes. In the U.S. in 1982, for example, 128,000 tonnes of petroleum polymer resins were produced [2], much of which was used in the paint and varnish industry. In commercial production in the USSR are a dark-colored styrene-lndene resin and light-colored petroleum polymer resins of two types --

Yu. V. Dumskii; M. E. Belyakov; A. K. Suroto; G. F. Cherednikova; L. B. Grin'ko

1988-01-01

244

A NOVEL STRONTIUM-SELECTIVE EXTRACTION CHROMATOGRAPHIC RESIN  

Microsoft Academic Search

The effect of nitric acid concentration on the selectivity of a novel extraction chromatographic resin consisting of an octanol solution of 4,4?(5?)-bis(t-butyl-cyclohexano)-18-crown-6 sorbed on an inert polymeric support for strontium over a number of alkali, alkaline earth, and other metal cations was evaluated. The effect of macro quantities of selected elements on strontium retention by the resin was also examined.

E. Philip Horwitz; Renato Chiarizia; Mark L. Dietz

1992-01-01

245

Experience with Urea-Resin Stabilization of Soils  

Microsoft Academic Search

In construction practice, the procedure of injecting gel-forming grout into soil after its pretreatment is currently used primarily for the urea-resin stabilization of sandy soils where hydrochloric and oxalic acids are mainly used as hardeners. The Scientific-Research Institute of Foundations and Underground Structures has developed new formulas based on urea resin and the following complex hardeners: Fe 2 (SO 4

N. A. Bleskina

2005-01-01

246

FIA-AAS determination of salicylic acid by a solid-phase reactor of copper carbonate incorporated in polyester resin beads  

Microsoft Academic Search

The determination of salicylic acid was carried out by reaction of the drug with copper carbonate entrapped in a polymeric material in a solid-phase reactor; the released cupric ions were monitored by flame atomic absorption at 324.8 nm. The calibration graph is linear over the range 4.0–75 ?g ml?1 of salicylic acid, with a relative standard deviation of less than

G. A. Rivas; J. Martínez Calatayud

1995-01-01

247

ANALYSIS OF VENTING OF A RESIN SLURRY  

SciTech Connect

A resin slurry venting analysis was conducted to address safety issues associated with overpressurization of ion exchange columns used in the Purex process at the Savannah River Site (SRS). If flow to these columns were inadvertently interrupted, an exothermic runaway reaction could occur between the ion exchange resin and the nitric acid used in the feed stream. The nitric acid-resin reaction generates significant quantities of noncondensable gases, which would pressurize the column. To prevent the column from rupturing during such events, rupture disks are installed on the column vent lines. The venting analysis models accelerating rate calorimeter (ARC) tests and data from tests that were performed in a vented test vessel with a rupture disk. The tests showed that the pressure inside the test vessel continued to increase after the rupture disk opened, though at a slower rate than prior to the rupture. Calculated maximum discharge rates for the resin venting tests exceeded the measured rates of gas generation, so the vent size was sufficient to relieve the pressure in the test vessel if the vent flow rate was constant. The increase in the vessel pressure is modeled as a transient phenomenon associated with expansion of the resin slurry/gas mixture upon rupture of the disk. It is postulated that the maximum pressure at the end of this expansion is limited by energy minimization to approximately 1.5 times the rupture disk burst pressure. The magnitude of this pressure increase is consistent with the measured pressure transients. The results of this analysis demonstrate the need to allow for a margin between the design pressure and the rupture disk burst pressure in similar applications.

Laurinat, J.; Hensel, S.

2012-03-27

248

Resin impregnation process for producing a resin-fiber composite  

NASA Technical Reports Server (NTRS)

Process for vacuum impregnation of a dry fiber reinforcement with a curable resin to produce a resin-fiber composite, by drawing a vacuum to permit flow of curable liquid resin into and through a fiber reinforcement to impregnate same and curing the resin-impregnated fiber reinforcement at a sufficient temperature and pressure to effect final curing. Both vacuum and positive pressure, e.g. autoclave pressure, are applied to the dry fiber reinforcement prior to application of heat and prior to any resin flow to compact the dry fiber reinforcement, and produce a resin-fiber composite of reduced weight, thickness and resin content, and improved mechanical properties. Preferably both a vacuum and positive pressure, e.g. autoclave pressure, are also applied during final curing.

Palmer, Raymond J. (Inventor); Moore, William E. (Inventor)

1994-01-01

249

Development of Polyimide Resins.  

National Technical Information Service (NTIS)

Polyimides are well-known to be attractive matrix resins for fiber-reinforced composites due to their superior thermal stability. However, their poor fabricability and high cost have been preventing them from being widely used. This paper reports three ap...

Y. Aito

1984-01-01

250

A NEW EXTRACTION CHROMATOGRAPHY RESIN CONTAINING KLÄUI LIGANDS FOR APPLICATION IN ACTINIDE SEPARATIONS  

SciTech Connect

An extraction chromatography resin containing the anionic ligand (?5-pentamethylcyclopentadienyl)tris-(diethylphosphito-P)cobalt(III), (L) has been prepared. The resin consists of 1 wt% L on Amberlite® XAD-7. This resin strongly sorbs Am(III) and Pu(IV). The sorption of these ions decreases with increasing nitric acid concentration, but this effect is more pronounced for Am(III). This allows for convenient separation of Am(III) from Pu(IV) by simple adjustments in the nitric acid concentration. The tripodal geometry of L disfavors the complexation of uranyl ion, so sorption of U(VI) by the L-containing resin is weak.

Lumetta, Gregg J.; Wester, Dennis W.; McNamara, Bruce K.; Hubler, Timothy L.; Latesky, Stanley L.; Martyr, Cuthbert C.; Richards, Kia N.

2004-11-01

251

Nontoxic Resins Advance Aerospace Manufacturing  

NASA Technical Reports Server (NTRS)

The 2008 NASA Commercial Invention of the Year, PETI-330, is a polyimide matrix resin that performs well at high temperatures and is easily processed into composites in a simple, short curing cycle. Invented by scientists at Langley Research Center, PETI-330 is now licensed to Ube Industries, based in Japan with its American headquarters in New York. In addition to being durable and lightweight, the resin is also nontoxic, which makes it safe for workers to handle. PETI-330 was created specifically for heat-resistant composites formed with resin transfer molding and resin infusion, which formerly could only be used with low temperature resin systems.

2009-01-01

252

Selective extraction of U(VI), Th(IV), and La(III) from acidic matrix solutions and environmental samples using chemically modified Amberlite XAD-16 resin  

Microsoft Academic Search

A new grafted polymer has been developed by the chemical modification of Amberlite XAD-16 (AXAD-16) polymeric matrix with [(2-dihydroxyarsinoylphenylamino)methyl]phosphonic acid (AXAD-16-AsP). The modified polymer was characterized by a combination of 13C CPMAS and 31P solid-state NMR, Fourier transform-NIR-FIR-Raman spectroscopy, CHNPS elemental analysis, and thermogravimetric analysis (TGA). The distribution studies for the extraction of U(VI), Th(IV), and La(III) from acidic solutions

D. Prabhakaran; M. S. Subramanian

2004-01-01

253

Pre-esterification of FFA in plant oil transesterified into biodiesel with the help of solid acid catalysis of sulfonated cation-exchange resin  

Microsoft Academic Search

One of the ways for the economically reasonable biodiesel production is to use the low quality plant oil as the cost advantageous feedstock. However, a large amount of free fatty acids (FFA) contained in the low quality plant oil causes the various problems: slowdown of the base-catalyzed transesterification, loss of the produced biodiesel and so on. Therefore, much interest has

Masato Kouzu; Atsuko Nakagaito; Jyu-suke Hidaka

2011-01-01

254

Method for digesting spent ion exchange resins and recovering actinides therefrom using microwave radiation  

DOEpatents

The present invention relates to methods for digesting diphosphonic acid substituted cation exchange resins that have become loaded with actinides, rare earth metals, or heavy metals, in a way that allows for downstream chromatographic analysis of the adsorbed species without damage to or inadequate elution from the downstream chromatographic resins. The methods of the present invention involve contacting the loaded diphosphonic acid resin with concentrated oxidizing acid in a closed vessel, and irradiating this mixture with microwave radiation. This efficiently increases the temperature of the mixture to a level suitable for digestion of the resin without the use of dehydrating acids that can damage downstream analytical resins. In order to ensure more complete digestion, the irradiated mixture can be mixed with hydrogen peroxide or other oxidant, and reirradiated with microwave radiation.

Maxwell, III, Sherrod L. (Aiken, SC); Nichols, Sheldon T. (Augusta, GA)

1999-01-01

255

Management of Spent Organic Ion-Exchange Resins by Photochemical Oxidation  

SciTech Connect

Management of spent ion-exchange resin waste arising from nuclear reactor operations by traditional practice of encapsulation in cement is associated with problems such as swelling and disintegration. Complete oxidation (mineralization) is an attractive alternative option. This paper reports the development of photochemical mineralization process for organic ion-exchange resins of poly (styrene-divinyl benzene) type with sulfonic acid and quaternary ammonium functional groups. It is a two-step process consisting of dissolution (conversion of solid resin into water-soluble reaction products) and photo-Fenton mineralization of the dissolved resin. Cation and anion resin dissolution was effected by reaction of the resin with H2O2 at 50-60 C in the presence of ferrous/copper sulphate catalyst. Direct dissolution of mixed resin was not efficient. However, the cation resin portion in the mixed resin could be selectively dissolved without affecting the anion portion. The solid anion resin after separation from the cation resin solution could be dissolved. About 0.5 liters of 50% H2O2 was required for dissolution of one kg of wet resin. The reaction time was 4-5 hours. Dissolution experiments were conducted on up to 8 liters of wet resin. The second step, viz., photo-Fenton mineralization of the dissolved resin was effected at ambient temperature(25-35 C). Kinetic results of laboratory scale experiments in immersion type photo-reactor and pilot scale experiments in tubular flow photo-reactor were presented. These results clearly demonstrated the photo-Fenton mineralization of dissolved resin at ambient temperature with stoichiometric quantity of H2O2 as against 70-200% excess H2O2 requirement in chemical mineralization experiments under Fenton oxidation conditions at 90-95 C. Based on these studies, a treatment scheme was developed and presented in this paper.

Srinivas, C.; Sugilal, S.; Wattal, P. K.

2003-02-26

256

Effects of the addition of fluoride to a 4-META/MMA-TBB-based resin adhesive on fluoride release, acid resistance of enamel and shear bond strength in vitro.  

PubMed

This study investigated fluoride release, acid resistance and shear bond strength (SBS) of new 4-META/MMA-TBB-based fluoride-containing resin adhesive (Super-Bond/F3). Super-Bond, Transbond Plus and Fuji Ortho LC were selected for comparison. Fluoride release into distilled water during 6-month period was measured using disk-shaped specimens. Brackets were bonded to human premolars with each material and then the specimens for the nanoindentation test were subjected to alternating immersion (demineralizing and remineralizing solutions); the hardness and elastic modulus of the enamel around bracket were determined. Rest of the specimens was subjected to examine the SBS. Super-Bond/F3 and Fuji Ortho LC showed significantly greater fluoride release compared with the other materials. The reductions in hardness and the elastic modulus for Super-Bond/F3 and Fuji Ortho LC were lower than those for the other materilas. Super-Bond and Super-Bond/F3 showed significantly greater SBS than Fuji Ortho FC. In conclusion, Super-Bond/F3 showed high fluoride-release, cariostatic potential and equivalent SBS. PMID:23370885

Iijima, Masahiro; Ito, Shuichi; Nakagaki, Susumu; Muguruma, Takeshi; Kohda, Naohisa; Saito, Takashi; Mizoguchi, Itaru

2013-01-01

257

Decomposition of Rare Earth Loaded Resin Particles  

SciTech Connect

The Fuel Cycle R and D (FCR and D) program within the Department of Energy Office of Nuclear Energy (DOE-NE) is evaluating nuclear fuel cycle options, including once-through, modified open, and fully closed cycles. Each of these scenarios may utilize quite different fuel management schemes and variation in fuel types may include high thermal conductivity UO{sub 2}, thoria-based, TRISO, metal, advanced ceramic (nitride, carbide, composite, etc.), and minor actinide (MA) bearing fuels and targets. Researchers from the US, Europe, and japan are investigating methods of fabricating high-specific activity spherical particles for fuel and target applications. The capital, operating, and maintenance costs of such a fuel fabrication facility can be significant, thus fuel synthesis and fabrication processes that minimize waste and process losses, and require less footprint are desired. Investigations have been performed at the Institute for Transuranium Elements (ITU) and the French Atomic Energy Commission (CEA) studying the impact of americium and curium on the fuel fabrication process. proof of concept was demonstrated for fabrication of MA-bearing spherical particles, however additional development will be needed for engineering scale-up. Researchers at the Paul Scherer Institute (PSI) and the Japan Atomic Energy Association (JAEA) have collaborated on research with ceramic-metallic (CERMET) fuels using spherical particles as the ceramic component dispersed in the metal matrix. Recent work at the CEA evaluates the burning of MA in the blanket region of sodium fast reactors. There is also interest in burning MA in Canada Deuterium Uranium (CANDU) reactors. The fabrication of uranium-MA oxide pellets for a fast reactor blanket or MA-bearing fuel for CANDU reactors may benefit from a low-loss dedicated footprint for producing MA-spherical particles. One method for producing MA-bearing spherical particles is loading the actinide metal on a cation exchange resin. The AG-50W resin is made of sulfonic acid functional groups attached to a styrene divinylbenzene copolymer lattice (long chained hydrocarbon). The metal cation binds to the sulfur group, then during thermal decomposition in air the hydrocarbons will form gaseous species leaving behind a spherical metal-oxide particle. Process development for resin applications with radioactive materials is typically performed using surrogates. For americium and curium, a trivalent metal like neodymium can be used. Thermal decomposition of Nd-loaded resin in air has been studied by Hale. Process conditions were established for resin decomposition and the formation of Nd{sub 2}O{sub 3} particles. The intermediate product compounds were described using x-ray diffraction (XRD) and wet chemistry. Leskela and Niinisto studied the decomposition of rare earth (RE) elements and found results consistent with Hale. Picart et al. demonstrated the viability of using a resin loading process for the fabrication of uranium-actinide mixed oxide microspheres for transmutation of minor actinides in a fast reactor. For effective transmutation of actinides, it will be desirable to extend the in-reactor burnup and minimize the number of recycles of used actinide materials. Longer burn times increases the chance of Fuel Clad Chemical or Mechanical Interaction (FCCI, FCMI). Sulfur is suspected of contributing to Irradiation Assisted Stress Corrosion Cracking (IASCC) thus it is necessary to maximize the removal of sulfur during decomposition of the resin. The present effort extends the previous work by quantifying the removal of sulfur during the decomposition process. Neodymium was selected as a surrogate for trivalent actinide metal cations. As described above Nd was dissolved in nitric acid solution then contacted with the AG-50W resin column. After washing the column, the Nd-resin particles are removed and dried. The Nd-resin, seen in Figure 1 prior to decomposition, is ready to be converted to Nd oxide microspheres.

Voit, Stewart L [ORNL; Rawn, Claudia J [ORNL

2010-09-01

258

Distribution of thorium during full loading of carboxylic acid cation exchange resins with uranium from nitrate solutions at 30 and 40°C  

Microsoft Academic Search

The recycle of ²³³U for the refabrication of fuel elements for a high-temperature gas-cooled reactor will require an assessment of chemical specifications for impurities in the uranyl nitrate product stream from the fuel reprocessing facility. The behavior of thorium, as an impurity in this simulated process stream, was investigated under equilibrium conditions during full loading of carboxylic acid cation exchange

J. H. Shaffer; C. W. Greene

1978-01-01

259

Flame Retardant Epoxy Resins  

NASA Technical Reports Server (NTRS)

As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.

2004-01-01

260

The adsorption of basic dyes from aqueous solution on modified peat–resin particle  

Microsoft Academic Search

Modified peat was prepared by mixing thoroughly raw peat with sulfuric acid, and modified peat–resin particle was obtained, by mixing modified peat with solutions of polyvinylalcohol (PVA) and formaldehyde. In this paper, the adsorption of Basic Magenta and Basic Brilliant Green onto modified peat–resin particle is examined. The adsorption isotherm showed that the adsorption of basic dyes on modified peat–resin

Qingye Sun; Linzhang Yang

2003-01-01

261

Proton conducting polymer electrolytes based on phosphorylated phenol–formaldehyde resins  

Microsoft Academic Search

Phosphorylated phenol–formaldehyde (PPF) resins were synthesized and investigated as the acidic components of proton conducting polymer electrolytes. The synthesis of PPF resins was carried out by melt polycondensation of monophenyl phosphate and formaldehyde (in the form of trioxane). The structure and molecular weight characterization of PPF resins were performed employing 1H-, 13C- and 31P-NMR spectroscopy, Fast Atom Bombardment mass spectrometry

Micha? K?dzierski; Zbigniew Florja?czyk

2006-01-01

262

Characterization of phenol–formaldehyde resins derived from liquefied lodgepole pine barks  

Microsoft Academic Search

In this study, lodgepole pine (Pinus contorta Dougl.) barks with and without infestation by mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) were liquefied in phenol with sulfuric acid. The liquefied portions of the bark were used to synthesize bark-derived phenol–formaldehyde (BPF) adhesive resins under alkaline conditions. In comparison to a commercial phenol–formaldehyde (PF) resin and a lab PF resin, the

Yong Zhao; Ning Yan; Martin Feng

2010-01-01

263

Structure and properties of boron-containing bisphenol-A formaldehyde resin  

Microsoft Academic Search

The boron-containing bisphenol-A formaldehyde resin from bisphenol-A, formaldehyde and boric acid was synthesized. The mechanism of synthesis and curing reaction were investigated by infrared spectroscopy and chemical analysis method. The kinetics of thermal degradation and thermal stability were determined by thermal analysis. The results show that the resin has higher heat resistant property and oxidative resistance than common phenol–formaldehyde resin.

Jungang Gao; Yanfang Liu; Fengli Wang

2001-01-01

264

Removal of chromium(III) by cation exchange resin, Indion 790 for tannery waste treatment  

Microsoft Academic Search

Extraction of chromium(III) from a model solution and from a tannery waste solution was studied by ion exchange using Indion 790 resin which is a macro-porous strongly acidic cation exchange resin of sulfonated polystyrene group. The resin was found to be selective for the sorption of chromium(III) in the pH range 0.5–3.5 from a model solution containing 500ppm Cr(III). Beyond

S. K. Sahu; P. Meshram; B. D. Pandey; V. Kumar; T. R. Mankhand

2009-01-01

265

The Acrylic Resin Leather Coating Agent Modified by Nano-SiO2  

Microsoft Academic Search

The acrylic resin leather coating agent modified by nano-SiO2 is investigated in this article. Nano-SiO2 is prepared by the sol–gel reaction from tetraethoxysilane (TEOS) catalyzed with acid and mixed with an acrylic resin. The properties of nano-SiO2 particles at different aging times are studied. The physical–mechanical properties of the films from modified acrylic resin by nano-SiO2 sol particles are obtained.

Jianzhong Ma; Jing Hu; Zhijie Zhang; Lingyun Liu

2006-01-01

266

Manufacture of cellulose nanocrystals by cation exchange resin-catalyzed hydrolysis of cellulose  

Microsoft Academic Search

Cellulose nanocrystals (CNC) were prepared from microcrystalline cellulose (MCC) by hydrolysis with cation exchange resin (NKC-9) or 64% sulfuric acid. The cation exchange resin hydrolysis parameters were optimized by using the Box–Behnken design and response surface methodology. An optimum yield (50.04%) was achieved at a ratio of resin to MCC (w\\/w) of 10, a temperature of 48°C and a reaction

Li-rong Tang; Biao Huang; Wen Ou; Xue-rong Chen; Yan-dan Chen

2011-01-01

267

Polymer-metal complexes of phenolic resin with Ln (III): thermal, catalytic and antimicrobial aspects  

Microsoft Academic Search

The polycondensation of 2-hydroxy-4-ethoxybenzophenone with 1, 3 butane diol was carried out in presence of polyphosphoric\\u000a acid as a catalyst at 155 °C for 10 h to synthesize desired resin. The resin was used to synthesize polymer-metal complexes\\u000a with 4f-block elements. The resin and its polymer-metal complexes were characterized on the basis of elemental analyses, electronic\\u000a spectra, magnetic susceptibilities, FTIR, NMR

Mihir Patel; Malav Kapadia; Jayantilal Joshi

2009-01-01

268

Quantitative analysis of PMR-15 polyimide resin by HPLC  

NASA Technical Reports Server (NTRS)

The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

Roberts, Gary D.; Lauver, Richard W.

1987-01-01

269

Effects of Resin Hydrophilicity on Dentin Bond Strength  

PubMed Central

The purpose of this study was to determine if hydrophobic resins can be coaxed into dentin wet with ethanol instead of water. The test hypothesis was that dentin wet with ethanol would produce higher bond strengths for hydrophobic resins than would dentin wet with water. This study examined the microtensile bond strength of 5 experimental adhesives (50 wt% ethanol/50% comonomers) of various degrees of hydrophilicity to acid-etched dentin that was left moist with water, moist with ethanol, or air-dried. Following composite buildups, hourglass-shaped slabs were prepared from the bonded teeth for microtensile testing. For all 3 types of dentin surfaces, higher bond strengths were achieved with increased resin hydrophilicity. The lowest bond strengths were obtained on dried dentin, while the highest bond strengths were achieved when dentin was bonded moist with ethanol. Wet-bonding with ethanol achieved higher bond strengths with hydrophobic resins than were possible with water-saturated matrices.

Nishitani, Y.; Yoshiyama, M.; Donnelly, A.M.; Agee, K.A.; Sword, J.; Tay, F.R.; Pashley, D.H.

2008-01-01

270

Amino acid analysis  

NASA Technical Reports Server (NTRS)

The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

Winitz, M.; Graff, J. (inventors)

1974-01-01

271

System for removing contaminants from plastic resin  

DOEpatents

A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2010-11-23

272

Dry PMR-15 Resin Powders  

NASA Technical Reports Server (NTRS)

Shelf lives of PMR-15 polymides lengthened. Procedure involves quenching of monomer reactions by vacuum drying of PRM-15 resin solutions at 70 to 90 degree F immediately after preparation of solutions. Absence of solvent eliminates formation of higher esters and reduces formation of imides to negligible level. Provides fully-formulated dry PMR-15 resin powder readily dissolvable in solvent at room temperature immediately before use. Resins used in variety of aerospace, aeronautical, and commercial applications.

Vannucci, Raymond D.; Roberts, Gary D.

1988-01-01

273

Vitrification of ion exchange resins  

DOEpatents

The present invention relates to vitrification of ion exchange resins that have become loaded with hazardous or radioactive wastes, in a way that produces a homogenous and durable waste form and reduces the disposal volume of the resin. The methods of the present invention involve directly adding borosilicate glass formers and an oxidizer to the ion exchange resin and heating the mixture at sufficient temperature to produce homogeneous glass.

Cicero-Herman, Connie A. (Aiken, SC); Workman, Rhonda Jackson (North Augusta, SC)

2001-01-01

274

Influence of metals on the phenol–formaldehyde resin degradation in friction composites  

Microsoft Academic Search

Degradation process and influence of metal particles (Cu, Fe, CuZn) on the stability of acid catalyzed (novolak) phenolic resin during curing and friction process in friction composites have been studied. Using TGA, FTIR and Py-GC methods, the significant influence of copper and iron chips, in case of high metal concentrations, on degradation process during curing of novolac phenolic resin has

Monika K???stková; Peter Filip; Zden?k Weiss; Rudolf Peter

2004-01-01

275

Development and Evaluation of Ion-Exchange Resins for Removal of Specific Metals in Water Treatment.  

National Technical Information Service (NTIS)

An ion-exchange resin specific for iron was developed and evaluated for its performance in removing iron from water supplies. The resin was synthesized by converting the carboxyl groups of Chelex 100 (Bio-Rad) to hydroxamic acids by reaction with ethyl-ch...

A. Winston C. R. Jenkins W. Lerdthusnee S. J. Masten

1981-01-01

276

Modified resin-intermediate processing of perovskite powders:Part I. Optimization of polymeric precursors  

Microsoft Academic Search

The formation of a polyester between citric acid (CA) and ethylene glycol (EG) was found to be a decisive factor for the foaming of resin intermediates in a Pechini-type powder process. This process was modified by changing the organic mass ratio of CA\\/EG which results in ceramic powders with different morphologies. The most porous resin intermediate (with or without chelated

Lone-Wen Tai; Paul A. Lessing

1992-01-01

277

A pyrolysis-based technology for recovering useful materials from IC package molding resin waste  

Microsoft Academic Search

This paper describes a pyrolysis-based technology for recovering useful materials from molding resin waste, which is the main type of thermosetting plastic waste generated in the fabrication of IC packages. In our pyrolysis of molding resin waste, the main impurities in the recovered silica were carbon (C), antimony (Sb) and phosphoric acid ion (PO43). The amount of carbon and phosphoric

Y. Ikuta; M. Iji; D. Ayukawa; S. Shibano

1996-01-01

278

Phenolic cation exchange resin material for recovery of cesium and strontium  

Microsoft Academic Search

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear waste solutions. The organic resins are condensation

M. A. Ebra; R. M. Wallace

1983-01-01

279

Phenolic cation-exchange resin material for recovery of cesium and strontium. [Patent application  

Microsoft Academic Search

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear wate solutions. The organic resins are condensation

M. A. Ebra; R. M. Wallace

1982-01-01

280

Comparison between different ion exchange resins for the deacidification of passion fruit juice  

Microsoft Academic Search

Passion fruit is highly appreciated for its aroma, but its strong acidity limits its use in formulated food products. In this study, deacidification of clarified passion fruit juice using ion exchange resins has been evaluated. Ten commercial weakly basic anion exchange resins were compared using a 50 ml column. The deacidification was carried out in order to increase juice pH

Edwin Vera; Manuel Dornier; Jenny Ruales; Fabrice Vaillant; Max Reynes

2003-01-01

281

21 CFR 177.1380 - Fluorocarbon resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Fluorocarbon resins. 177.1380 Section 177.1380 Food and Drugs...Food Contact Surfaces § 177.1380 Fluorocarbon resins. Fluorocarbon resins may be safely used as articles or components...

2011-04-01

282

21 CFR 177.1595 - Polyetherimide resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyetherimide resin. 177.1595 Section 177.1595 Food and Drugs...Contact Surfaces § 177.1595 Polyetherimide resin. The polyetherimide resin identified in this section may be safely...

2012-04-01

283

21 CFR 177.1595 - Polyetherimide resin.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyetherimide resin. 177.1595 Section 177.1595 Food and Drugs...Contact Surfaces § 177.1595 Polyetherimide resin. The polyetherimide resin identified in this section may be safely...

2011-04-01

284

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and Drugs...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

2011-04-01

285

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Polyestercarbonate resins. 177.1585 Section 177.1585 Food and...Contact Surfaces § 177.1585 Polyestercarbonate resins. Polyestercarbonate resins may be safely used as articles or...

2010-01-01

286

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Terpene resins. 178.3930 Section 178.3930 Food and Drugs...Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of this...

2012-04-01

287

21 CFR 177.1680 - Polyurethane resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyurethane resins. 177.1680 Section 177.1680 Food and...Contact Surfaces § 177.1680 Polyurethane resins. The polyurethane resins identified in paragraph (a) of this...

2011-04-01

288

40 CFR 721.9495 - Acrylosilane resins.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Acrylosilane resins. 721.9495 Section 721.9495 ...Substances § 721.9495 Acrylosilane resins. (a) Chemical substance and significant...chemical substances identified as acrylosilane resins (PMNs P-95-1024/1040) are...

2012-07-01

289

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2012-04-01 false Resin applicator. 872.3140 Section 872.3140...DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device intended...

2012-04-01

290

21 CFR 872.3140 - Resin applicator.  

... 2014-04-01 2014-04-01 false Resin applicator. 872.3140 Section 872.3140...DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device intended...

2014-04-01

291

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyestercarbonate resins. 177.1585 Section 177.1585 Food and...Contact Surfaces § 177.1585 Polyestercarbonate resins. Polyestercarbonate resins may be safely used as articles or...

2011-04-01

292

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Resin applicator. 872.3140 Section 872.3140...DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device intended...

2011-04-01

293

40 CFR 721.9495 - Acrylosilane resins.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Acrylosilane resins. 721.9495 Section 721.9495 ...Substances § 721.9495 Acrylosilane resins. (a) Chemical substance and significant...chemical substances identified as acrylosilane resins (PMNs P-95-1024/1040) are...

2010-07-01

294

21 CFR 177.1560 - Polyarylsulfone resins.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Polyarylsulfone resins. 177.1560 Section 177.1560 Food and Drugs...Contact Surfaces § 177.1560 Polyarylsulfone resins. Polyarylsulfone resins (CAS Reg. No. 79293-56-4) may be...

2010-01-01

295

21 CFR 177.1380 - Fluorocarbon resins.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Fluorocarbon resins. 177.1380 Section 177.1380 Food and Drugs...Food Contact Surfaces § 177.1380 Fluorocarbon resins. Fluorocarbon resins may be safely used as articles or components...

2010-01-01

296

21 CFR 177.1680 - Polyurethane resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyurethane resins. 177.1680 Section 177.1680 Food and...Contact Surfaces § 177.1680 Polyurethane resins. The polyurethane resins identified in paragraph (a) of this...

2012-04-01

297

21 CFR 177.1560 - Polyarylsulfone resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyarylsulfone resins. 177.1560 Section 177.1560 Food and Drugs...Contact Surfaces § 177.1560 Polyarylsulfone resins. Polyarylsulfone resins (CAS Reg. No. 79293-56-4) may be...

2011-04-01

298

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Resin applicator. 872.3140 Section 872.3140...DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device intended...

2010-04-01

299

40 CFR 721.9495 - Acrylosilane resins.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Acrylosilane resins. 721.9495 Section 721.9495 ...Substances § 721.9495 Acrylosilane resins. (a) Chemical substance and significant...chemical substances identified as acrylosilane resins (PMNs P-95-1024/1040) are...

2011-07-01

300

40 CFR 721.9495 - Acrylosilane resins.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Acrylosilane resins. 721.9495 Section 721.9495 ...Substances § 721.9495 Acrylosilane resins. (a) Chemical substance and significant...chemical substances identified as acrylosilane resins (PMNs P-95-1024/1040) are...

2013-07-01

301

21 CFR 177.2440 - Polyethersulfone resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyethersulfone resins. 177.2440 Section 177.2440 Food and...Repeated Use § 177.2440 Polyethersulfone resins. Polyethersulfone resins identified in paragraph (a) of this...

2011-04-01

302

21 CFR 177.1560 - Polyarylsulfone resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyarylsulfone resins. 177.1560 Section 177.1560 Food and Drugs...Contact Surfaces § 177.1560 Polyarylsulfone resins. Polyarylsulfone resins (CAS Reg. No. 79293-56-4) may be...

2012-04-01

303

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyestercarbonate resins. 177.1585 Section 177.1585 Food and...Contact Surfaces § 177.1585 Polyestercarbonate resins. Polyestercarbonate resins may be safely used as articles or...

2012-04-01

304

21 CFR 177.1595 - Polyetherimide resin.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Polyetherimide resin. 177.1595 Section 177.1595 Food and Drugs...Contact Surfaces § 177.1595 Polyetherimide resin. The polyetherimide resin identified in this section may be safely...

2010-01-01

305

21 CFR 177.2440 - Polyethersulfone resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyethersulfone resins. 177.2440 Section 177.2440 Food and...Repeated Use § 177.2440 Polyethersulfone resins. Polyethersulfone resins identified in paragraph (a) of this...

2012-04-01

306

21 CFR 177.1380 - Fluorocarbon resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Fluorocarbon resins. 177.1380 Section 177.1380 Food and Drugs...Food Contact Surfaces § 177.1380 Fluorocarbon resins. Fluorocarbon resins may be safely used as articles or components...

2012-04-01

307

A p-methylbenzhydrylamine resin for improved solid-phase synthesis of peptide amides.  

PubMed

A p-methylbenzhydrylamine-resin, alpha-(p-tolyl)-amino-aminomethyl-functionalized copoly(styrene-1%-dvinylbenzene), was prepared for the improved solid-phase synthesis of peptide alpha-carboxamides. Following a Friedel-Crafts acylation of polymer beads, the resulting ketone resin was reductively aminated via the Leuckart reaction. A comparison of the relative acid stability of the p-methylbenzhydrylamine-(MBHA)-, benzhydrylamine (BHA)- and alpha-phenyethylamine-resins indicated that the p-methylbenzhydrylamine-resin provided the best yields of the model peptide carboxamides. PMID:7243625

Matsueda, G R; Stewart, J M

1981-01-01

308

Indirect resin composites  

PubMed Central

Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth is limited to relatively small cavities due to polymerization stresses. Indirect composites offer an esthetic alternative to ceramics for posterior teeth. This review article focuses on the material aspect of the newer generation of composites. This review was based on a PubMed database search which we limited to peer-reviewed articles in English that were published between 1990 and 2010 in dental journals. The key words used were ‘indirect resin composites,’ composite inlays,’ and ‘fiber-reinforced composites.’

Nandini, Suresh

2010-01-01

309

Effect of pH on Porphyromonas gingivalis endotoxin affinity for resins.  

PubMed

This study evaluated the effect of pH on Porphyromonas gingivalis lipopolysaccharide (LPS) affinity for polymethyl methacrylate, polyethyl methacrylate, and polyethyl and polyisobutyl methacrylate resins. Specimens were exposed to 1,010 endotoxin units LPS in potassium phosphate buffer at pH 6, pH 7, or pH 8. Control specimens were incubated in LPS-free water. Sequence I evaluated LPS uptake and release from resin when exposure and elution pH were identical, whereas Sequence II evaluated LPS release from resin when elution pH differed from exposure pH. A slightly acidic pH decreased LPS affinity for all resins compared to pH 7. A slightly alkaline pH increased LPS affinity for the polyethyl methacrylate resin but decreased LPS affinity for the others compared to pH 7. The pH may affect resin-LPS affinity by altering LPS molecular charge. PMID:8957858

Knoernschild, K L; Tompkins, G R; Lefebvre, C A; Griffiths, L L; Schuster, G S

1996-01-01

310

Imide Modified Epoxy Matrix Resins.  

National Technical Information Service (NTIS)

Results of a program designed to develop tough imide modified epoxy (IME) resins cured by bisimide amine (BIA) hardeners are presented. State of the art epoxy resin, MY720, was used. Three aromatic bisimide amines and one aromatic aliphatic BIA were evalu...

D. A. Scola

1982-01-01

311

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

High char yield epoxy using novel bisimide amines (BIA's) as curing agents with a state of the art epoxy resin was developed. Stoichiometric quantities of the epoxy resin and the BIA's were studied to determine the cure cycle required for preparation of resin specimens. The bisimide cured epoxies were designated IME's (imide modified epoxy). The physical, thermal and mechanical properties of these novel resins were determined. The levels of moisture absorption exhibited by the bisimide amine cured expoxies (IME's) were considerably lower than the state of the art epoxies. The strain-to-failure of the control resin system was improved 25% by replacement of DDS with 6F-DDS. Each BIA containing resin exhibited twice the char yield of the control resin MY 720/DDS. Graphite fiber reinforced control (C) and IME resins were fabricated and characterized. Two of the composite systems showed superior properties compared to the other Celion 6000/IME composite systems and state of the art graphite epoxy systems. The two systems exhibited excellent wet shear and flexural strengths and moduli at 300 and 350 F.

Scola, D. A.; Pater, R. H.

1981-01-01

312

Uranium removal from contaminated groundwater by synthetic resins.  

PubMed

Synthetic resins are shown to be effective in removing uranium from contaminated groundwater. Batch and field column tests showed that strong-base anion-exchange resins were more effective in removing uranium from both near-neutral-pH (6.5)- and high-pH (8)-low-nitrate-containing groundwaters, than metal-chelating resins, which removed more uranium from acidic-pH (5)-high-nitrate-containing groundwater from the Oak Ridge Reservation (ORR) Y-12 S-3 Ponds area in Tennessee, USA. Dowex 1-X8 and Purolite A-520E anion-exchange resins removed more uranium from high-pH (8)-low-nitrate-containing synthetic groundwater in batch tests than metal-chelating resins. The Dowex 21K anion-exchange resin achieved a cumulative loading capacity of 49.8 mg g(-1) before breakthrough in a field column test using near-neutral-pH (6.5)-low-nitrate-containing groundwater. However, in an acidic-pH (5)-high-nitrate-containing groundwater, metal-chelating resins Diphonix and Chelex-100 removed more uranium than anion-exchange resins. In 15 m L of acidic-pH (5)-high-nitrate-containing groundwater spiked with 20 mg L(-1) uranium, the uranium concentrations ranged from 0.95 mg L(-1) at 1-h equilibrium to 0.08 mg L(-1) at 24-h equilibrium for Diphonix and 0.17 mg L(-1) at 1-h equilibrium to 0.03 mg L(-1) at 24-h equilibrium for Chelex-100. Chelex-100 removed more uranium in the first 10 min in the 100mL of acidic-(pH 5)-high-nitrate-containing groundwater ( approximately 5 mg L(-1) uranium); however, after 10 min, Diphonix equaled or out-performed Chelex-100. This study presents an improved understanding of the selectivity and sorption kenetics of a range of ion-exchange resins that remove uranium from both low- and high-nitrate-containing groundwaters with varying pHs. PMID:17697694

Phillips, D H; Gu, B; Watson, D B; Parmele, C S

2008-01-01

313

Design and Synthesis of Prototype Air-Dry Resins for Use in BEP (Bureau of Engraving and Printing) Intaglio Ink Vehicles.  

National Technical Information Service (NTIS)

Over 60 air-dry resins were designed and synthesized to provide prototype resins for intaglio inks used in the Bureau of Engraving and Printing for printing currency. Most of the resins contain linseed oil fatty acids as the air-dry part. The polysols use...

B. Dickens B. J. Bauer W. R. Blair E. J. Parks

1989-01-01

314

Copper resinate: an XPS study of degradation  

NASA Astrophysics Data System (ADS)

In this paper, we describe an X-ray photoelectron spectroscopy (XPS) study of copper resinate, a transparent green glaze that is coloured by copper salts of resin acids. This pigment was used in Europe in the fifteenth and sixteenth centuries, but it does not seem to be a usual feature of the palette anywhere after the end of the sixteenth century, because its tendency to discolour was already widely known by artists. An essential prerequisite for the restoration of works of art is the understanding of the effects of various climatic parameters on the deterioration process. For this reason, pictorial models of copper resinate in linseed oil, capable of simulating the ancient paintings on mobile supports, were prepared and aged in a climatic chamber, under different conditions such as exposure to UV radiations, humidity and different concentration of chemical pollutants (NO2 and SO2). All the samples were investigated by XPS and the data obtained were evaluated in order to estimate aging effects as well as mechanisms of degradation. On these paint layers damage induced by X-ray irradiation was also verified.

Altavilla, C.; Ciliberto, E.

2006-06-01

315

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

The results of a program designed to develop tough imide modified epoxy resins cured by bisimide amine (BIA) hardeners are described. State-of-the-art epoxides MY720 and DER383 were used, and four bismide amines were evaluated. These were the BIA's derived from the 6F anhydride (4,4'-(hexafluoroisopropylidene) bis(phthalic anhydride) and the diamines 3,3'-diaminodiphynyl sulfone, 4,4'-oxygianiline, 4,4'-methylene dianiline, and 1,12-dodecane diamine. A key intermediate, designated 6F anhydride, is required for the synthesis of the bisimide amines. Reaction parameters to synthesize a precursor to the 6F anhydride (6FHC) in high yields were investigated. The catalyst trifluoromethane sulfonic acid was studied. Although small scale runs yielded the 6FHC in 50 percent yield, efforts to ranslate these results to a larger scale synthesis gave the 6FHC in only 9 percent yield. Results show that the concept of using bisimide amine as curing agents to improve the toughness properties of epoxies is valid.

Scola, D. A.

1984-01-01

316

Quantitative evaluation of XAD-8 and XAD-4 resins used in tandem for removing organic solutes from water  

USGS Publications Warehouse

The combined XAD-8 and XAD-4 resin procedure for the isolation of dissolved organic solutes from water was found to isolate 85% or more of the organic solutes from Lake Skjervatjern in Norway. Approximately 65% of the dissolved organic carbon (DOC) was first removed on XAD-8 resin, and then an additional 20% of the DOC was removed on XAD-4 resin. Approximately 15% of the DOC solutes (primarily hydrophilic neutrals) were not sorbed or concentrated by the procedure. Of the 65% of the solutes removed on XAD-8 resin, 40% were fulvic acids, 16% were humic acids, and 9% were hydrophobic neutrals. Approximately 20% of the hydrophilic solutes that pass through the XAD-8 resin were sorbed solutes on the second resin, XAD-4 (i.e., they were hydrophobic relative to the XAD-4 resin). The fraction sorbed on XAD-4 resin was called XAD-4 acids because it represented approximately 85-90% of the hydrophilic XAD-8 acid fraction according to the original XAD-8 fractionation procedure. The recovery of hydrophobic acids (fulvic acids and humic acids) and the hydrophobic neutral fraction from XAD-8 resin was essentially quantitative at 96%, 98%, and 86%, respectively. The recovery of XAD-4 acids from the XAD-4 resin was only about 50%. The exact reason for this moderately low recovery is unknown, but could result from ??-?? bonding between these organic solutes and the aromatic matrix of XAD-4. The hydrophobic/hydrophilic solute separation on XAD-8 resin for water from background Side A and Side B of the lake was almost identical at 65 and 67%, respectively. This result suggested that both sides of the lake are similar in organic chemical composition even though the DOC variation from side to side is 20%.

Malcolm, R. L.; MacCarthy, P.

1992-01-01

317

Quantitative evaluation of XAD-8 and XAD-4 resins used in tandem for removing organic solutes from water  

SciTech Connect

The combined XAD-8 and XAD-4 resin procedure for the isolation of dissolved organic solutes from water was found to isolate 85% or more of the organic solutes from Lake Skjervatjern in Norway. Approximately 65% of the dissolved organic carbon (DOC) was first removed on XAD-8 resin, and then an additional 20% of the DOC was removed on XAD-4 resin. Approximately 15% of the DOC solutes (primarily hydrophilic neutrals) were not sorbed or concentrated by the procedure. Of the 65% of the solutes removed on XAD-8 resin, 40% were fulvic acids, 16% were humic acids, and 9% were hydrophobic neutrals. Approximately 20% of the hydrophilic solutes that pass through the XAD-8 resin were sorbed solutes on the second resin, XAD-4 (i.e., they were hydrophobic relative to the XAD-4 resin). The fraction sorbed on XAD-4 resin was called XAD-4 acids because it represented approximately 85-90% of the hydrophilic XAD-8 acid fraction according to the original XAD-8 fractionation procedure. The recovery of hydrophobic acids (fulvic acids and humic acids) and the hydrophobic neutral fraction from XAD-8 resin was essentially quantitative at 96%, 98%, and 86%, respectively. The recovery of XAD-4 acids from the XAD-4 resin was only about 50%. The exact reason for this moderately low recovery is unknown, but could result from [pi]-[pi] bonding between these organic solutes and the aromatic matrix of XAD-4. The hydrophobic/hydrophilic solute separation on XAD-8 resin for water from background Side A and Side B of the lake was almost identical at 65 and 67%, respectively. This result suggested that both sides of the lake are similar in organic chemical composition even though the DOC variation from side to side is 20%. 12 refs., 5 figs., 3 tabs.

Malcolm, R.L. (Geological Survey, Denver, CO (United States)); MacCarthy, P. (Colorado School of Mines, Golden (United States))

1992-01-01

318

Detoxification of lignocellulose hydrolysates with ion-exchange resins.  

PubMed

Lignocellulose hydrolysates contain fermentation inhibitors causing decreased ethanol production. The inhibitors include phenolic compounds, furan aldehydes, and aliphatic acids. One of the most efficient methods for removing inhibiting compounds prior to fermentation is treatment of the hydrolysate with ion-exchange resins. The performance and detoxification mechanism of three different resins were examined: an anion exchanger, a cation exchanger, and a resin without charged groups (XAD-8). A dilute acid hydrolysate of spruce was treated with the resins at pH 5.5 and 10.0 prior to ethanolic fermentation with Saccharomyces cerevisiae. In addition to the experiments with hydrolysate, the effect of the resins on selected model compounds, three phenolics (vanillin, guaiacol, and coniferyl aldehyde) and two furan aldehydes (furfural and hydroxymethyl furfural), was determined. The cation exchanger increased ethanol production, but to a lesser extent than XAD-8, which in turn was less effective than the anion exchanger. Treatment at pH 10.0 was more effective than at pH 5.5. At pH 10.0, the anion exchanger efficiently removed both anionic and uncharged inhibitors, the latter by hydrophobic interactions. The importance of hydrophobic interactions was further indicated by a substantial decrease in the concentration of model compounds, such as guaiacol and furfural, after treatment with XAD-8. PMID:11963864

Nilvebrant, N O; Reimann, A; Larsson, S; Jönsson, L J

2001-01-01

319

Furfural resin-based bio-nanocomposites reinforced by reactive nanocrystalline cellulose  

NASA Astrophysics Data System (ADS)

The work presented herein has been focused on reinforcing the furfural resins (FA) by reactive-modified nanocrystalline cellulose (NCC) in an attempt to create a bio-nanocomposite completely based on natural resources. FA prepolymers were synthesized with an acid catalyst, and NCC was rendered reactive via the grafting of maleic anhydride (MAH). The resulting NCC and nanocomposites were characterized using TEM, SEM and FT-IR. It was found that NCC appeared to be spherical in shape with diameters under 100 nm. FT-IR confirmed that there were hydrogen and esterification bonding between MAH and NCC or FA prepolymer. After solidified with paratoluenesulfonic acid, NCC-reinforced FA resin composites showed granular cross-section while FA resin with layered structures. Mechanical property tests indicated that NCC-reinforced FA resin composites possessed the improved tensile and flexural strengths, in comparison with FA resin.

Wang, C.; Sun, S.; Zhao, G.; He, B.; Xiao, H.

2009-07-01

320

Radiation curable epoxy resin  

Microsoft Academic Search

A carboxyl containing polymer is either prepared in the presence of a polyepoxide or reacted with a polyepoxide. The polymer has sufficient acid groups to react with only about 1 to 10 percent of the epoxide (oxirane) groups. The remaining epoxide groups are reacted with an unsaturated monocarboxylic acid such as acrylic or methacrylic acid to form a radiation curable

Najvar

1978-01-01

321

Volume reduction of ion exchange resin by a pyrolysis technique  

Microsoft Academic Search

Volume reduction techniques, such as incineration and acid digestion, of spent ion exchange resins from nuclear power plants are being developed with a view toward reducing radioactive waste volume and also making the final waste form more stable. The authors chose pyrolysis as a technique that can be done at low operating temperatures and low gas flow rates in a

M. Matsuda; K. Funabashi; S. Uchida; M. Kikuchi

1985-01-01

322

Melamine-formaldehyde-NTA chelating gel resin: Synthesis, characterization and application for copper(II) ion removal from synthetic wastewater.  

PubMed

A new chelating resin was synthesised by anchoring nitrilotriacetic acid (NTA) to melamine during the melamine-formaldehyde gelling reaction in the presence of water, using acetone and guaiacol as a porogen mixture. This technique gives a porous chelating gel resin capable of removing heavy metals from wastewater. FT-IR, XRD, elemental analysis, surface area and water regain measurements were conducted for characterization of the new chelating gel resin. A comprehensive adsorption study (kinetics isotherm, and thermodynamics) of Cu(II) removal from synthetic acidic aqueous solutions by adsorption on this resin was conducted regarding the effects of time, temperature, initial pH and copper(II) initial concentration. PMID:16887265

Baraka, Ahmad; Hall, P J; Heslop, M J

2007-02-01

323

Chromatography resin support  

DOEpatents

An apparatus and method of using an improved chromatography resin support is disclosed. The chromatography support platform is provided by a stainless steel hollow cylinder adapted for being inserted into a chromatography column. An exterior wall of the stainless steel cylinder defines a groove for carrying therein an "O"-ring. The upper surface of the stainless steel column is covered by a fine stainless steel mesh welded to the edges of the stainless steel cylinder. When placed upon a receiving ledge defined within a chromatography column, the "O"-ring provides a fluid tight seal with the inner edge wall of the chromatography cylinder. The stainless steel mesh supports the chromatography matrix and provides a back flushable support which is economical and simple to construct.

Dobos, James G. (North Augusta, SC)

2002-01-01

324

Flammability screening tests of resins  

NASA Technical Reports Server (NTRS)

Selected flammability characteristics of glass cloth laminates of thermosetting resins are evaluated. A protocol for the evaluation of the flammability hazards presented by glass cloth laminates of thermosetting resins and the usefulness of that protocol with two laminates are presented. The glass laminates of an epoxy resin, M-751 are evaluated for: (1) determination of smoke generation from the laminates; (2) analysis of products of oxidative degradation of the laminates; (3) determination of minimum oxygen necessary to maintain flaming oxidation; (4) evaluation of toxicological hazards.

Arhart, R. W.; Farrar, D. G.; Hughes, B. M.

1979-01-01

325

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

High temperature resin matrices suitable for use in advanced graphite fiber composites for jet engine applications were evaluated. A series of planned, sequential screening experiments with resin systems in composite form were performed to reduce the number of candidates to a single A-type polyimide resin that repetitively produced void-free, high strength and modulus composites acceptable for use in the 550 F range for 1000 hours. An optimized processing procedure was established for this system. Extensive mechanical property studies characterized this single system, at room temperature, 500 F, 550 F and 600 F, for various exposure times.

Cavano, P. J.; Jones, R. J.; Vaughan, R. W.

1972-01-01

326

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorous. The pendent groups have the formula ##STR1## wherein R is hydrogen, a cation or mixtures thereof; and R.sup.1 is hydrogen or an C.sub.1 -C.sub.2 alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange-resin are also disclosed.

Trochimcznk, Andrzej W. (Knoxville, TN); Gatrone, Ralph C. (Plymouth, PA); Alexandratos, Spiro (Knoxville, TN); Horwitz, E. Philip (Naperville, IL)

1998-01-27

327

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorus. The pendent groups have the formula as shown in the patent wherein R is hydrogen, a cation or mixtures thereof; and R{sup 1} is hydrogen or an C{sub 1}-C{sub 2} alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange resin are also disclosed.

Trochimcznk, A.W.; Gatrone, R.C.; Alexandratos, S.; Horwitz, E.P.

1997-04-08

328

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorous. The pendent groups have the formula ##STR1## wherein R is hydrogen, a cation or mixtures thereof; and R.sup.1 is hydrogen or an C.sub.1 -C.sub.2 alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange resin are also disclosed.

Trochimcznk, Andrzej W. (Knoxbille, TN); Gatrone, Ralph C. (Plymouth, PA); Alexandratos, Spiro (Knoxville, TN); Horwitz, E. Philip (Naperville, IL)

1997-01-01

329

Reactive Additives for Phenylethynyl-Containing Resins  

NASA Technical Reports Server (NTRS)

Phenylethynyl-containing reactive additive (PERA) compounds and mixtures have been found to be useful for improving the processability of oligomers, polymers, co-oligomers, and copolymers that contain phenylethynyl groups. The additives can be incorporated in different forms: A solution of an amide acid or an imide of a PERA can be added to a solution of phenylethynyl-containing oligomer, polymer, co-oligomer, or copolymer; or An imide powder of a PERA can be mixed with a dry powder of a phenylethynyl-containing oligomer, polymer, co-oligomer, or copolymer. The effect of a given PERA on the processability and other properties of the resin system depends on whether the PERA is used in the amide acid or an imide form. With proper formulation, the PERA reduces the melt viscosity of the resin and thereby reduces the processing pressures needed to form the adhesive bonds, consolidate filled or unfilled moldings, or fabricate fiber-reinforced composite laminates. During thermal cure, a PERA reacts with itself as well as with the phenylethynyl-containing host resin and thereby becomes chemically incorporated into the resin system. The effects of the PERA on mechanical properties, relative to those of the host resin, depend on the amount of PERA used. Typically, the incorporation of the PERA results in (1) increases in the glass-transition temperature (Tg), modulus of elasticity, and parameters that characterize behavior under compression, and (2) greater retention of the aforementioned mechanical properties at elevated temperatures without (3) significant reduction of toughness or damage tolerance. Of the formulations tested thus far, the ones found to yield the best overall results were those for which the host resin was the amide acid form of a phenylethynyl-terminated imide (PETI) co-oligomer having a molecular weight of 5,000 g/mole [hence, designated PETI-5] and a PERA denoted as PERA-1. PETI-5 was made from 3,3',4'4'-biphenyltetracarboxylic dianhydride, 3,4'-oxydianiline (3,4'-ODA), 1,3-bis(3-aminophenoxy) benzene (1,3-APB), and 4-phenylethynylphthalic anhydride (PEPA). PERA-1 was made from 3,5-diamino- 4.-phenylethynylbenzophenon and equimolar amounts of phthalic anhydride and PEPA. To make PERA-1 in the imide form, the aforementioned ingredients were processed by refluxing in glacial acetic acid. To make the amide form of PERA-1, the ingredients were reacted in N-methyl-2-pyrrolidinone (NMP) under nitrogen at a temperature of 23 C (see figure). On the basis of the processability and other properties, a blend comprising 20 weight percent of PERA-1 and 80 weight percent PETI-5 was selected for further evaluation. Relative to neat PETI-5, the blend exhibited an increase in Tg; improved processability; and comparable values of shear strength in adhesion to titanium panels, open-hole compressive properties, compression properties after impact, and resistance to microcracking.

Connell, John W.; Smith, Joseph G., Jr.; Hergenrother, Paul M.; Rommel, Monica L.

2005-01-01

330

In vitro color change of three dental veneering resins in tea, coffee and tamarind extracts  

PubMed Central

Objective To study the in vitro color changes of three dental resin veneering materials when immersed in tea, coffee and tamarind extracts. Materials and Methods The color changes of heat polymerized tooth colored acrylic resin (Stellondetrey, B, F14, DPI Dental products of India Ltd, Mumbai), auto polymerized tooth colored acrylic resin (DPI, B, QV5, DPI Dental products of India Ltd, Mumbai) and light polymerized resin composite (Herculite XRV, Enamel A2, part no. 22860, lot no. 910437, Kerr Corporation, West Collins Avenue, Orange, CA, USA) when immersed in water extracts of tea (Tata Tea Ltd. Bangalore, India), coffee (Tata Coffee Ltd. Coorg, India) and tamarind were evaluated using computer vision systems. The color images were recorded in R (red), G (green) and B (blue) form and converted into H (hue), S (saturation) and V (value). Results Significant color change occurred for auto polymerized tooth colored acrylic resin in tamarind extract, for heat polymerized tooth colored acrylic resin in tea extract and for light polymerized resin composite in coffee extract. Auto polymerized tooth colored acrylic resin samples showed an overall higher color change. However, for all the material samples coffee extract produced more color change. Conclusion These results suggest that the color stability of the resins is influenced by the presence of secondary metabolites such as tartaric acid, tannins, caffeine, saponins and phenols in tamarind, tea and coffee extracts.

Subramanya, J.K.; Muttagi, S.

2011-01-01

331

Demineralizer operation with morpholine and boric acid  

Microsoft Academic Search

The effect on condensate and blowdown deep bed demineralizer performance of morpholine and boric acid are examined. The high concentration of morpholine required to reduce corrosion product transport exhausts demineralizer cation resin too fast to allow hydrogen cycle demineralizer operation. Extremely efficient resin separation and high crosslinked cation resins will be required to minimize sodium leakage during demineralizer morpholine cyde

Siegwarth

1992-01-01

332

The comparative effects of gamma radiation and in situ alpha particles on five strong-base anion exchange resins  

SciTech Connect

The effects of external gamma radiation and in situ alpha particles were measured on a recently available, macroporous, strong-base polyvinylpyridine resin and on four strong-base polystyrene anion exchange resins. Each resin was irradiated in 7 M nitric acid to 1--10 megaGray of gamma radiation from external {sup 60}Co, or to 5--14 megaGray of alpha particles from sorbed {sup 238}Pu. Each irradiated resin was measured for changes in dry weight, wet volume, weak-base and strong-base chloride exchange capacities, and exchange capacities for Pu(4) from nitric acid. Alpha-induced resin damage was significantly less than that caused by an equivalent dose of gamma radiation. The polyvinylpyridine resin offers the greatest resistance to damage from gamma radiation and from alpha particles. 5 refs., 1 figs. 5 tabs.

Marsh, S.F.

1991-01-01

333

Epoxy hydantoins as matrix resins  

NASA Technical Reports Server (NTRS)

Tensile strength and fracture toughness of castings of the hydantoin resins cured with methylenedianiline are significantly higher than MY 720 control castings. Water absorption of an ethyl, amyl hydantoin formulation is 2.1 percent at equilibrium and Tg's are about 160 C, approximately 15 deg below the final cure temperature. Two series of urethane and ester-extended hydantoin epoxy resins were synthesized to determine the effect of crosslink density and functional groups on properties. Castings cured with methylenedianiline or with hexahydrophthalic anhydride were made from these compounds and evaluated. The glass transition temperatures, tensile strengths and moduli, and fracture toughness values were all much lower than that of the simple hydantoin epoxy resins. Using a methylene bishydantoin epoxy with a more rigid structure gave brittle, low-energy fractures, while a more flexible, ethoxy-extended hydantoin epoxy resin gave a very low Tg.

Weiss, J.

1983-01-01

334

Regenerating Water-Sterilizing Resins  

NASA Technical Reports Server (NTRS)

Iodine-dispensing resin can be regenerated after iodine content has been depleted, without being removed from water system. Resin is used to make water potable by killing bacteria, fungi, and viruses. Regeneration technique may be come basis of water purifier for very long space missions. Enough crystalline iodine for multiple regenerations during mission can be stored in one small cartridge. Cartridge could be inserted in waterline as necessary on signal from iodine monitor or timer.

Colombo, G. V.; Putnam, D. F.

1982-01-01

335

Process for the preparation of lactic acid and glyceric acid  

DOEpatents

Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

2008-12-02

336

Pentasaccharide resin glycosides from Ipomoea cairica and their cytotoxic activities.  

PubMed

Six partially acylated pentasaccharide resin glycosides, cairicosides A-F, were isolated from the aerial parts of Ipomoea cairica. These compounds were characterized as a group of macrolactones of simonic acid A, partially acylated with different organic acids. The lactonization site of 11S-hydroxyhexadecanoic acid (jalapinolic acid) was bound to the second saccharide moiety at C-3 in cairicosides A-E, while at C-2 in cairicoside F. Structures were established by spectroscopic and chemical methods. Compounds cairicosides A-E exhibited moderate cytotoxicity against a small panel of human tumor cell lines with IC50 values in the range of 4.28-14.31?M. PMID:23954073

Yu, Bangwei; Luo, Jianguang; Wang, Junsong; Zhang, Dongming; Yu, Shishan; Kong, Lingyi

2013-11-01

337

Dissolution of ion exchange resin by hydrogen peroxide  

SciTech Connect

The resin dissolution process was conducted successfully in full-scale equipment at the SRL Semiworks. A solution containing 0.001M Fe/sup 2 +/, or Fe/sup 3 +/, and 3 vol % H/sub 2/O/sub 2/ in 0.1M HNO/sub 3/ is sufficient to dissolve up to 40 vol % resin slurry (Dowex 50W-X8). Foaming and pressurization can be eliminated by maintaining the dissolution temperature below 99/sup 0/C. The recommended dissolution temperature range is 85 to 90/sup 0/C. Premixing hydrogen peroxide with all reactants will not create a safety hazard, but operating with a continual feed of hydrogen peroxide is recommended to control the dissolution rate. An air sparging rate of 1.0 to 1.5 scfm will provide sufficient mixing. Spent resin from chemical separation contains DTPA (diethylenetriaminepentaacetic acid) residue, and the resin must be washed with 0.1M NH/sub 4/ OH to remove excess DTPA before dissolution. Gamma irradiation of resin up to 4 kW-hr/L did not change the dissolution rate significantly.

Lee, S.C.

1981-08-01

338

Cariogenic bacteria degrade dental resin composites and adhesives.  

PubMed

A major reason for dental resin composite restoration replacement is related to secondary caries promoted by acid production from bacteria including Streptococcus mutans (S. mutans). We hypothesized that S. mutans has esterase activities that degrade dental resin composites and adhesives. Standardized specimens of resin composite (Z250), total-etch (Scotchbond Multipurpose, SB), and self-etch (Easybond, EB) adhesives were incubated with S. mutans UA159 or uninoculated culture medium (control) for up to 30 days. Quantification of the BisGMA-derived biodegradation by-product, bishydroxy-propoxy-phenyl-propane (BisHPPP), was performed by high-performance liquid chromatography. Surface analysis of the specimens was performed by scanning electron microscopy (SEM). S. mutans was shown to have esterase activities in levels comparable with those found in human saliva. A trend of increasing BisHPPP release throughout the incubation period was observed for all materials and was more elevated in the presence of bacteria vs. control medium for EB and Z250, but not for SB (p < .05). SEM confirmed the increased degradation of all materials with S. mutans UA159 vs. control. S. mutans has esterase activities at levels that degrade resin composites and adhesives; degree of degradation was dependent on the material's chemical formulation. This finding suggests that the resin-dentin interface could be compromised by oral bacteria that contribute to the progression of secondary caries. PMID:24026951

Bourbia, M; Ma, D; Cvitkovitch, D G; Santerre, J P; Finer, Y

2013-11-01

339

Energy value of paraquat-treated and resin-soaked lobolly pine  

SciTech Connect

With a basal injector, loblolly pines were treated with 5% paraquat cation (weight/weight basis) and harvested after 18 months. The resin acid, turpentine, moisture content (MC) and energy value were measured in three bolts of the stem. In bolt 1, the first 152 cm above the injection site, the increase in resin acids was 392% and in turpentine, 564%. Within the whole stem (the first two 152 cm bolts and the third bolt to a 7.6 cm inside-bark diameter) resin acids and turpentine increased 203 and 296% respectively. Moisture content was reduced 9%, 8%, and 8% in bolts 1, 2 and 3, respectively. Turpentine from treated and untreated trees had an average heating value of 19,369 cal/g. When weighted for volume, net energy content was 7.8% greater for treated than control trees because of the increase in resin, including turpentine and the lowered MC.

Kossuth, S.V.; Roberts, D.R.; Huffman, J.B.; Wang, S.C.

1984-07-01

340

Ion-exchange resins in non-aqueous solvents-I Sorption rates of p-nitroaniline and the effects of small amounts of water.  

PubMed

The rates of sorption of p-nitroaniline onto three hydrogenform resins in methanol, ethanol, n-propanol, isopropanol, n-butanol, acetonitrile, benzene, acetic acid and dioxan are reported. Two of the resins are typical gel-type, microreticular, sulphonated resins and the third is a new, highly porous and rigid, macroreticular, sulphonated resin, Amberlyst 15. There appears to be a correlation between viscosity or dielectric constant and the time for maximum sorption or maximum distribution coefficient when the alcohols are used, but no correlation for all the solvents is apparent. The macroreticular resin still functions when dry, even in the presence of non-polar solvents, but the microreticular resin does not. Small amounts of water present in the solvent or resin aid the sorption of the amine onto both types of resin. The effect of mesh size and cross-linkage are examined. PMID:18959870

Pietrzyk, D J

1966-02-01

341

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2010 CFR

... α-Methylstyrene-vinyltoluene resins, hydrogenated. 178.3610 Section... ?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1...

2010-01-01

342

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2012 CFR

... α-Methylstyrene-vinyltoluene resins, hydrogenated. 178.3610 Section... ?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1...

2012-04-01

343

21 CFR 178.3610 - ?-Methylstyrene-vinyltoluene resins, hydrogenated.  

Code of Federal Regulations, 2011 CFR

... α-Methylstyrene-vinyltoluene resins, hydrogenated. 178.3610 Section... ?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1...

2011-04-01

344

Alkyd-amino resins based on waste PET for coating applications.  

PubMed

Waste polyethylene terephthalate (PET) flakes were depolymerized by using propylene glycol (PG) in the presence of zinc acetate as catalyst. Glycolysis reaction products of waste PET obtained by using PET/glycol molar ratio 1/2. Two short oil alkyd resins of high acid values (30-40mgKOH/g) were prepared from phthalic anhydride (PA), glycerin (G), coconut oil fatty acids (COFA) and glycolyzed products of waste PET (PET-based alkyd resins) or glycols (PG) (reference alkyd resins). These alkyd resins were blended with 30%, 40%, and 50% of a commercial urea-formaldehyde, melamine-formaldehyde and urea-formaldehyde/melamine-formaldehyde mixture (1/1 weight ratio) and heated at 140 degrees C. The physical and chemical properties such as drying time, hardness, abrasion resistance, adhesion strength, water resistance, alkaline resistance, acid resistance, gelation time, and thermal oxidative degradation resistance (with thermogravimetric analysis, TGA) of these alkyd-amino resins were investigated. The properties of the waste PET-based resins were found to be compatible with the properties of the reference resins. PMID:18424023

Torlako?lu, A; Güçlü, G

2009-01-01

345

K Basin sludge/resin bead separation test report  

SciTech Connect

The K Basin sludge is an accumulation of fuel element corrosion products, organic and inorganic ion exchange materials, canister gasket materials, iron and aluminum corrosion products, sand, dirt and minor amounts of other organic material. The sludge will be collected and treated for storage and eventual disposal. This process will remove the large solid materials by a 1/4 inch screen. The screened material will be subjected to nitric acid in a chemical treatment process. The organic ion exchange resin beads produce undesirable chemical reactions with the nitric acid. The resin beads must be removed from the bulk material and treated by another process. An effective bead separation method must extract 95% of the resin bead mass without entraining more than 5% of the other sludge component mass. The test plan I-INF-2729, ``Organic Ion Exchange Resin Separation Methods Evaluation,`` proposed the evaluation of air lift, hydro cyclone, agitated slurry and elutriation resin bead separation methods. This follows the testing strategy outlined in section 4.1 of BNF-2574, ``Testing Strategy to Support the Development of K Basins Sludge Treatment Process``. Engineering study BNF-3128, ``Separation of Organic Ion Exchange Resins from Sludge,`` Rev. 0, focused the evaluation tests on a method that removed the fine sludge particles by a sieve and then extracted the beads by means of a elutriation column. Ninety-nine percent of the resin beads are larger than 125 microns and 98.5 percent are 300 microns and larger. Particles smaller than 125 microns make up the largest portion of sludge in the K Basins. Eliminating a large part of the sludge`s non-bead component will reduce the quantity that is lifted with the resin beads in the elutriation column. Resin bead particle size distribution measurements are given in Appendix A The Engineering Testing Laboratory conducted measurements of a elutriation column`s ability to extract resin beads from a sieved, non-radioactive sludge simulant. A elutriation column uses a constant velocity upward flow stream to segregate materials. In simplistic terms, the dense particles fall to the column`s bottom while the flow lifts less dense particles to the column`s top. A particle can be streamlined or have a high drag profile; this factor also influences the lift or fall of a particle exposed to the column flow. The sludge components that lift or fall are determined by the fluid velocity. The column flow velocity needed to lift the bulk of the resin beads will also lift other, non-bead, sludge components. Resin bead treatment and disposal are complicated by large quantities of non-bead material. Tests are necessary to determine a column flow velocity that will collect the bulk of the resin beads and the amount of non-bead sludge components that are also collected.

Squier, D.M.

1998-08-25

346

Irradiation effects in the storage and disposal of radioactive ion-exchange resins  

SciTech Connect

Research is under way to characterize the effects of self-irradiation on radwastes which may be generated when organic ion-exchange media are used in water demineralization or decontamination operations at nuclear facilities. External factors affecting the relation between laboratory evaluations and field performance are emphasized. Initial experiments do not yet indicate substantial radiation dose-rate effects on radiolytic gas yields or acid product formation, when (fully swollen) sulfonic acid resins are irradiated in a sealed air environment. At the same time, oxygen gas is removed from the environment of irradiated resins. Interaction between mild steel coupons and acidic species produced in the irradiation induced decomposition of sulfonic acid resin results in irradiation enhanced corrosion. Corrosion rates depend on radiation dose rate, moisture content and resin chemical loading. In some cases, corrosion rates decrease with time, suggesting depletion of acidic species within the resin bed, or a synergistic interaction between resin and corrosion coupon. Implications of these and other results on evaluating field behavior of radwaste containing ion-exchange media are discussed. 4 figures, 2 tables.

Swyler, K.J.; Dodge, C.E.; Dayal, R.; Weiss, A.J.

1982-01-01

347

Coemulsion and electrodeposition properties of mixtures of cationic epoxy resin and cationic acrylic resin containing butoxymethylamide groups  

SciTech Connect

Butyl acrylate, styrene, N,N-dimethylaminoethylmethacrylate, and N-(n-butoxy-methyl) acrylamide were copolymerized to prepare a cationic acrylic copolymer (I) containing butoxymethylamide groups. This copolymer can be mixed with an epoxy-amine adduct (II), acetic acid, and deionized water to form a coemulsion containing two cationic resins. The electrophoretic codeposition of the coemulsion and physical and chemical properties of the deposited film were investigated. The resin composition of film deposited from coemulsion was determined by Fourier transform Infrared (FTIR) quantitative analysis to study the coemulsion and electrophoretic codeposition behavior. The applicability of this two-component coemulsion in primer-surfacer (pricer) electrodeposition paint was also discussed. The results indicate that at any coemulsion resin composition the resin composition of electrodeposited film is almost equal to the coemulsion resin composition. The throwing power of emulsion increases with increasing applied voltage, as expected. However, the throwing power of coemulsion is almost equal to that of the II emulsion but greater than that of the I emulsion. Furthermore, all cured films derived from mixtures of I/II show excellent adhesive strength, good hardness, and high levels of salt spray resistance.

Chinping Yang; Yahnhaur Chen (Tatung Inst. of Tech., Taipei (Taiwan, Province of China). Dept. of Chemical Engineering)

1993-10-15

348

Phenolic cation-exchange resin material for recovery of cesium and strontium. [Patent application  

DOEpatents

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear wate solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs/sup +/ and Sr/sup 2 +/ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

Ebra, M.A.; Wallace, R.M.

1982-05-05

349

Phenolic cation exchange resin material for recovery of cesium and strontium  

DOEpatents

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear waste solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs.sup.+ and Sr.sup.2+ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

Ebra, Martha A. (Aiken, SC); Wallace, Richard M. (Aiken, SC)

1983-01-01

350

WEAK-ACID ION EXCHANGE FOR REMOVING BARIUM, RADIUM, AND HARDNESS  

EPA Science Inventory

Weak-acid resin in the hydrogen form was found to effectively remove barium, radium, and hardness, without increasing the sodium content of the product water. The maximum capacity of the weak-acid resin was about 2.3 times that of strong-acid resin, and much less spent regenerant...

351

Technical Task and Quality Assurance Plan in Support of BNFL Part B: Studies of Ion Exchange Resin Integrity under Flowsheet Extremes: Part II  

SciTech Connect

This task will address four items related to ion exchange stability: (1) process upset evaluation of resin in contact with 1 molar sodium permanganate at 25 and 40 degrees C, (2) accelerated aging with nitric acid solution used during normal regeneration operations, (3) prolonged contacting of SuperLig 644 resin with 5 molar nitric acid at room temperature, and (4) prolonged contacting of SuperLig 644 resin with deionized water at 60 plus/minus 5 degrees C.

Nash, C.A.

2000-08-23

352

Diphonix-CS : a novel combined cesium and strontium selective ion exchange resin.  

SciTech Connect

The recently developed Diphonix{reg_sign} resin contains the geminally substituted diphosphonic acid ligand chemically bonded to a styrene-divinylbenzene copolymer. The resin exhibits an extraordinarily strong affinity for actinides, especially in the terra- and hexavalent oxidation states. Therefore the resin has potential for application in TRU removal from nuclear wastes. The Diphonix-CS resin is a Diphonix-type resin that contains also phenolic groups chemically attached to the polymeric matrix. The phenolic groups exhibit high affinity for Cs{sup +} ions from highly alkaline media. Thanks to the combined action of the diphosphonic acid and the phenolic groups, the Diphonix-CS resin can simultaneously remove actinide species, Cs and Sr from alkaline media. In this paper the results obtained in the characterization of the new resin are reported, with regard to the uptake equilibrium and kinetics of Cs+ and Sr+2 removal from NaOH solutions and from synthetic alkaline wastes. The chemical and radiolytic stability of the resin has been investigated. The results have indicated that the Diphonix-CS resin is remarkably stable under the experimental conditions of this work (up to 35 days in I to 4 M NaOH, and up to 200 MRad gamma ray absorbed dose). The possibility of stripping the Cs{sup +} and Sr{sup +2} from the resin has been investigated in column experiments by using 1 M HNO{sub 3} as the stripping agent. Some problems encountered in the stripping of Sr{sup +2} and possible ways to improve the stripping performance are discussed.

Chiarizia, R.; Horwitz, E. P.; Beauvais, R. A.; Alexandratos, S. D.; Chemistry; Univ. of Tennessee

1998-01-01

353

Sorption of trace heavy metals by thiol containing chelating resins  

SciTech Connect

The sorption of copper, cadmium, nickel and zinc ions on thiol (-SH) based chelating polymeric resins (thiomethyl resin and Duolite GT-73) has been investigated. The physical and chemical characterization of these polymers in the form of scanning electron micrographs (SEM), BET and Langmuir surface area measurements. Fourier transform infra red spectroscopy (FTIR) analysis, X-ray photoelectron spectroscopy (XPS) analysis, atomic composition measurement, sodium capacity determination and zeta potential measurements have been conducted to assess their performance as sorbents for trace toxic metal removal. Density functional theory (DFT) has been used to analyze the pore size distribution data. The adsorption of metal ions from aqueous solution on these sorbents has been studied in batch equilibrium experiments. The influence of pH on metal adsorption capacity has also been examined. The kinetic performance of these polymers has been assessed and the results have been analyzed by a pore diffusion model. The resins have been used in mini-columns to study the selectivity towards the desired metal ion. The desorption of metal ions has been studied using hydrochloric acid (1 M and 4 M), sulfuric acid (1 M and 4 M) and acidified thiourea. The present study confirms that these thiol based chelating resins are very effective for selective removal of trace heavy metals from water.

Saha, B.; Iglesias, M.; Cumming, I.W.; Streat, M.

2000-01-01

354

Low Melt Viscosity Resins for Resin Transfer Molding  

NASA Technical Reports Server (NTRS)

In recent years, resin transfer molding (RTM) has become one of the methods of choice for high performance composites. Its cost effectiveness and ease of fabrication are major advantages of RTM. RTM process usually requires resins with very low melt viscosity (less than 10 Poise). The optimum RTM resins also need to display high thennal-oxidative stability, high glass transition temperature (T(sub g)), and good toughness. The traditional PMR-type polyimides (e.g. PMR-15) do not fit this requirement, because the viscosities are too high and the nadic endcap cures too fast. High T(sub g), low-melt viscosity resins are highly desirable for aerospace applications and NASA s Reusable Launch Vehicle (RLV) program. The objective of this work is to prepare low-melt viscosity polyimide resins for RTM or resin film infusion (RFI) processes. The approach involves the synthesis of phenylethynyl-terminated imide oligomers. These materials have been designed to minimize their melt viscosity so that they can be readily processed. During the cure, the oligomers undergo both chain extension and crosslinking via the thermal polymerization of the phenylethynyl groups. The Phenylethynyl endcap is preferred over the nadic group due to its high curing temperature, which provides broader processing windows. This work involved the synthesis and polymerization of oligomers containing zig-zag backbones and twisted biphenyl structures. Some A-B type precursors which possessed both nitro and anhydride functionality, or both nitro and amine functionality, were also synthesized in order to obtain the well defined oligomers. The resulting zig-zag structured oligomers were then end-capped with 4-phenylethynylphthalic anhydride (PEPA) for further cure. The properties of these novel imide oligomers are evaluated.

Harris, Frank W.

2002-01-01

355

Chromatographic Studies of the Lanthanide Element Separation for the Americium/Curium Large Scale Separation Using Ion Exchange Resins.  

National Technical Information Service (NTIS)

The Am/Cm large scale separations, operated by chromatography with the use of ion exchange resins, are described. Use of sulfonate cationic resins; development by elution with the alpha hydroxyisobutyric acid; column loadings between 1 and 30% of the capa...

C. Ginisty

1981-01-01

356

Effect of ferrioxalate-exchanged resin on the removal of 2,4-D by a photocatalytic process  

Microsoft Academic Search

A new approach combining sorption and an advanced oxidation process has been developed for wastewater treatment. Fe3+ is incorporated into a cationic resin with or without the oxalate to afford two types of catalyst: ferrioxalate-exchanged resin (FOR) and ferric-exchange resin (FR), respectively. The removal of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) by different resin-mediated processes including sole FOR, FOR\\/H2O2, UV\\/FOR, UV\\/R\\/H2O2, UV\\/FR\\/H2O2,

Cheuk Yan Kwan; Wei Chu

2006-01-01

357

Bond strength of self-adhesive resin cements to composite submitted to different surface pretreatments  

PubMed Central

Objectives Extensively destroyed teeth are commonly restored with composite resin before cavity preparation for indirect restorations. The longevity of the restoration can be related to the proper bonding of the resin cement to the composite. This study aimed to evaluate the microshear bond strength of two self-adhesive resin cements to composite resin. Materials and Methods Composite discs were subject to one of six different surface pretreatments: none (control), 35% phosphoric acid etching for 30 seconds (PA), application of silane (silane), PA + silane, PA + adhesive, or PA + silane + adhesive (n = 6). A silicone mold containing a cylindrical orifice (1 mm2 diameter) was placed over the composite resin. RelyX Unicem (3M ESPE) or BisCem (Bisco Inc.) self-adhesive resin cement was inserted into the orifices and light-cured. Self-adhesive cement cylinders were submitted to shear loading. Data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). Results Independent of the cement used, the PA + Silane + Adhesive group showed higher microshear bond strength than those of the PA and PA + Silane groups. There was no difference among the other treatments. Unicem presented higher bond strength than BisCem for all experimental conditions. Conclusions Pretreatments of the composite resin surface might have an effect on the bond strength of self-adhesive resin cements to this substrate.

dos Santos, Victor Hugo; Griza, Sandro; de Moraes, Rafael Ratto

2014-01-01

358

Fatigue of the Resin-Enamel Bonded Interface and the Mechanisms of Failure  

PubMed Central

The durability of adhesive bonds to enamel and dentin and the mechanisms of degradation caused by cyclic loading are important to the survival of composite restorations. In this study a novel method of evaluation was used to determine the strength of resin-enamel bonded interfaces under both static and cyclic loading, and to identify the mechanisms of failure. Specimens with twin interfaces of enamel bonded to commercial resin composite were loaded in monotonic and cyclic 4-point flexure to failure within a hydrated environment. Results for the resin-enamel interface were compared with those for the resin composite (control) and values reported for resin-dentin adhesive bonds. Under both modes of loading the strength of the resin-enamel interface was significantly (p?0.0001) lower than that of the resin composite and the resin-dentin bonded interface. Fatigue failure of the interface occurred predominately by fracture of enamel, adjacent to the interface, and not due to adhesive failures. In the absence of water aging or acid production of biofilms, the durability of adhesive bonds to enamel is lower than that achieved in dentin bonding.

Yahyazadehfar, Mobin; Mutluay, Mustafa Murat; Majd, Hessam; Ryou, Heonjune; Arola, Dwayne

2013-01-01

359

Speciation and surface interactions of actinides on aged ion-exchange resins  

SciTech Connect

The United States Department of Energy is presently faced with the stabilization and safe disposition of hundreds of metric tons of residue materials resulting from 50+ years of nuclear weapons production activities. These residues encompass a broad range of substrates and radionuclides and include both solid and liquid materials. Combustible residues constitute a significant fraction of the total residue inventory, and an important constituent within the combustible category is spent anion ion-exchange resins. These resins are typically utilized for the separation of plutonium from other radionuclides under strongly acidic nitric or hydrochloric acid solution conditions which favor the formation and partitioning of anionic Pu(IV) nitrato or chloride species. The spent resins are usually rinsed prior to storage as residues to reduce both acid and radionuclide concentrations, but significant radionuclide concentrations remain in these resins, and the long-term effects of concentrated acid and radiolysis on the resin integrity are relatively unexplored. Thus, new research is needed to assess the stability of these resin residues and address the need for further treatment to ensure stability prior to long-term disposal.

Morris, D.E.; Buscher, C.T.; Donohoe, R.J. [and others

1997-09-01

360

Radionuclide Leaching from Organic Ion Exchange Resin  

SciTech Connect

Laboratory tests were performed to examine the efficacy of leach treatments for decontaminating organic ion exchange resins (OIER), which have been found in a number of samples retrieved from K East Basin sludge. Based on process records, the OIER found in the K Basins is a mixed-bet strong acid/strong base material marketed as Purolite{trademark} NRW-037. Radionuclides sorbed or associated with the OIER can restrict its disposal to the Environmental Restoration Disposal Facility (ERDF). The need for testing to support development of a treatment process for K Basin sludge has been described in Section 4.2 of ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process'' (Flament 1998). To help understand the effects of anticipated OIER elutriation and washing, tests were performed with well-rinsed OIER material from K East Basin floor sludge (sample H-08 BEAD G) and with well-rinsed OIER having approximately 5% added K East canister composite sludge (sample KECOMP). The rinsed resin-bearing material also contained the inorganic ion exchanger Zeolon-900{trademark}, a zeolite primarily composed of the mineral mordenite. The zeolite was estimated to comprise 27 weight percent of the dry H-08 BEAD G material.

Delegard, C.H.; Rinehart, D.E.

1999-04-02

361

Characterization of PMR Polyimide Resin and Prepreg.  

National Technical Information Service (NTIS)

Procedures for the chemical characterization of PMR-15 resin solutions and graphite-reinforced prepregs were developed, and a chemical data base was established. In addition, a basic understanding of PMR-15 resin chemistry was gained; this was translated ...

C. H. Sheppard P. H. Lindenmeyer

1984-01-01

362

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2013 CFR

...following specifications: (i) The solution intrinsic viscosity of the polyestercarbonate resins shall be a minimum of 0...per gram, as determined by a method entitled âIntrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

2013-04-01

363

Microparticle and Fiber Reinforcement of Epoxy Resins.  

National Technical Information Service (NTIS)

Microparticle and fiber materials have been investigated as reinforcing agents for a diglycidyl ether of bisphenol a type of epoxy resin. These materials were limited to low concentrations in order to insure retention of the resin binder properties, such ...

A. G. Sands E. J. Kohn R. C. Clark

1966-01-01

364

Soluble high molecular weight polyimide resins  

NASA Technical Reports Server (NTRS)

High molecular weight polyimide resins have greater than 20 percent /by weight/ solubility in polar organic solvents. They permit fabrication into films, fibers, coatings, reinforced composite, and adhesive product forms. Characterization properties for one typical polyimide resin are given.

Jones, R. J.; Lubowitz, H. R.

1970-01-01

365

Hyperbranched Polymers for Resin Transfer Molding.  

National Technical Information Service (NTIS)

The purpose of this proposal study new low viscosity thermoset additives - hyperbranched polymers (HBPs) - as processing aids and toughening additives for high performance resin transfer molding (RTM) resins. The proposed research project will culminate w...

P. T. Mather

2005-01-01

366

Rapid Curing Epoxy Resins Derived from Resorcinol.  

National Technical Information Service (NTIS)

Epoxy resins that can be cured rapidly at room temperature are highly desirable from the production standpoint. A new epoxy resin, diglycidyl ether of 4-methylol resorcinol was synthesized. In the molecule, the hydroxyl from the methylol substituent is pr...

J. J. Schmid W. McCarvill

1974-01-01

367

21 CFR 177.1655 - Polysulfone resins.  

Code of Federal Regulations, 2012 CFR

...POLYMERS Substances for Use as Basic Components of Single and Repeated...25154-01-2) consisting of basic resins produced when the disodium salt of 4,4?-isopropylidenediphenol...dimethylformamide. (b) The basic polysulfone resins...

2012-04-01

368

21 CFR 177.1655 - Polysulfone resins.  

Code of Federal Regulations, 2011 CFR

...POLYMERS Substances for Use as Basic Components of Single and Repeated...25154-01-2) consisting of basic resins produced when the disodium salt of 4,4?-isopropylidenediphenol...dimethylformamide. (b) The basic polysulfone resins...

2011-04-01

369

Resins with Identical Specifications are not Identical. Identifying a Useful Solid-Phase Resin  

PubMed Central

The quality of the most commonly used support for solid phase syntheses, polystyrene resin cross linked with 1% of divinylbenzene, differs considerably even among different lots of resin from the same source. Determination of the swelling capacity of resins before carrying out solid-phase synthesis represents a very simple means of nondestructive pre-synthetic resin characterization.

Bouillon, Isabelle; Soural, Miroslav; Miller, Marvin J.; Krchnak, Viktor

2009-01-01

370

Effect of solution concentration and aging conditions on PMR-15 resin  

NASA Technical Reports Server (NTRS)

High performance liquid chromatography is utilized to evaluate the effect of temperature, solution concentration, and aging time on PMR-15 resin solutions. Fifty- and 70-wt percent PMR-15 resin solutions were prepared from the mixture of 5-norbornene-2,3-dicarboxylic ester (NE) acid, 4.4'-methylenedianiline (MDA), methanol, and 3,3',4.4.-benzophenonetetracarboxylic dimethyl ester (BTDE) acid solution. It is observed that in PMR-15 resin solution aged for 35 days at room temperature NE and MDA react to form amide and imide intermediates. The precipitation data reveal that in the 70-wt percent solution precipitation occurs after 12 days and in the 50-wt percent solution after 20 days; however, at lower temperatures (-11 C, and 2 C) no precipitation is detected. It is concluded that storage of resin solutions and powders at reduced temperatures extends shelf life by reducing the rate of imide formation.

Roberts, G. D.; Vannucci, R. D.

1986-01-01

371

Solventless LARC-160 Polyimide Matrix Resin.  

National Technical Information Service (NTIS)

The addition polyimide, LARC-160, which was originally synthesized from low cost liquid monomers as a laminating resin in ethanol, was prepared as a solventless, high viscosity, neat liquid resin. The resin was processed by hot-melt coating techniques int...

T. L. St Clair R. A. Jewell

1978-01-01

372

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Polyaryletherketone resins. 177.1556 Section 177.1556 ...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1...4-phenylenecarbonyl-1,4-phenylene) resins (CAS Reg. No. 55088-54-5 and...

2010-01-01

373

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Terpene resin. 172.280 Section 172.280 Food and Drugs...and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with the...

2012-04-01

374

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Terpene resin. 172.280 Section 172.280 Food and Drugs...and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance with the...

2011-04-01

375

21 CFR 177.1555 - Polyarylate resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyarylate resins. 177.1555 Section 177.1555 Food and Drugs...Food Contact Surfaces § 177.1555 Polyarylate resins. Polyarylate resins (CAS Reg. No. 51706-10-6) may be...

2011-04-01

376

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Polyaryletherketone resins. 177.1556 Section 177.1556 ...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1...4-phenylenecarbonyl-1,4-phenylene) resins (CAS Reg. No. 55088-54-5 and...

2012-04-01

377

21 CFR 177.1555 - Polyarylate resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyarylate resins. 177.1555 Section 177.1555 Food and Drugs...Food Contact Surfaces § 177.1555 Polyarylate resins. Polyarylate resins (CAS Reg. No. 51706-10-6) may be...

2012-04-01

378

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Polyaryletherketone resins. 177.1556 Section 177.1556 ...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1...4-phenylenecarbonyl-1,4-phenylene) resins (CAS Reg. No. 55088-54-5 and...

2011-04-01

379

Method of removing contaminants from plastic resins  

DOEpatents

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-11-18

380

Method for removing contaminants from plastic resin  

DOEpatents

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-12-30

381

Method of removing contaminants from plastic resins  

DOEpatents

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert,George W. (Harrisonville, MO); Hand,Thomas E. (Lee's Summit, MO); Delaurentiis,Gary M. (Jamestown, CA)

2007-08-07

382

Preparation of nano alumina via resin synthesis  

Microsoft Academic Search

The effect of type of precursor on the characteristics of alumina powders prepared via urea formaldehyde resin formation is demonstrated through the introduction of three different Al3+ precursors. An Al ester (aluminum acetate), and two inorganic salts aluminum sulphate and aluminum phosphate hydrate, were added during resin formation. The resins and the powders after burning out of the organic part

D. M. Ibrahim; Y. M. Abu-Ayana

2009-01-01

383

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2010 CFR

...5 0.5 5.1 Nylon 11 resins for use in articles intended...25 .3 5.2 Nylon 11 resins for use only: 1.04...with food b. In side-seam cements for articles intended for...this chapter 6.1 Nylon 6 resins 1.15±.015...

2009-04-01

384

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2010 CFR

...5 0.5 5.1 Nylon 11 resins for use in articles intended...25 .3 5.2 Nylon 11 resins for use only: 1.04...with food b. In side-seam cements for articles intended for...this chapter 6.1 Nylon 6 resins 1.15±.015...

2010-01-01

385

Effect of three boron flame retardants on thermal curing behavior of urea formaldehyde resin  

Microsoft Academic Search

The purpose of the study was to investigate the effects of three kinds of flame retardant (FR), boric acid, zinc borate, and\\u000a borax on the thermal curing behavior of urea–formaldehyde (UF) resin. Both pH value and gel time were measured to study the\\u000a curing characters of the UF resin with different loading levels of FR. In addition, differential thermal analysis

Jiang Jinxue; Yang Yonglin; Li Cheng; Li Jianzhang

2011-01-01

386

Control of micropore formation in the carbonized ion exchange resin by utilizing pillar effect  

Microsoft Academic Search

A new method is presented for controlling the micropore structure of porous carbon by use of pillar effect of metal and\\/or sulfur compounds. An ion exchange resin having sulfonic acid groups as ion exchangeable functional groups was used as a raw material. Resins having various cations of H+, K+, Na+, Ca2+, Zn2+, Cu2+, Fe2+, Ni2+ and Fe3+ were prepared from

H Nakagawa; K Watanabe; Y Harada; K Miura

1999-01-01

387

Devices using resin wafers and applications thereof  

SciTech Connect

Devices incorporating a thin wafer of electrically and ionically conductive porous material made by the method of introducing a mixture of a thermoplastic binder and one or more of anion exchange moieties or cation exchange moieties or mixtures thereof and/or one or more of a protein capture resin and an electrically conductive material into a mold. The mixture is subjected to temperatures in the range of from about 60.degree. C. to about 170.degree. C. at pressures in the range of from about 0 to about 500 psig for a time in the range of from about 1 to about 240 minutes to form thin wafers. Devices include electrodeionization and separative bioreactors in the production of organic and amino acids, alcohols or esters for regenerating cofactors in enzymes and microbial cells.

Lin, YuPo J. (Naperville, IL); Henry, Michael P. (Batavia, IL); Snyder, Seth W. (Lincolnwood, IL); St. Martin, Edward (Libertyville, IL); Arora, Michelle (Woodridge, IL); de la Garza, Linda (Woodridge, IL)

2009-03-24

388

Alternate Methods for Eluting Cesium from Spherical Resorcinol-Formaldehyde Resin  

SciTech Connect

A small-column ion exchange (SCIX) system has been proposed for removing cesium from the supernate and dissolved salt solutions in the high-level-waste tanks at the Savannah River Site (SRS). The SCIX system could use either crystalline silicotitanate (CST), an inorganic, non-regenerable sorbent, or spherical resorcinol-formaldehyde (RF), a new regenerable resin, to remove cesium from the waste solutions. The baseline method for eluting the cesium from the RF resin uses 15 bed volumes (BV) of 0.5 M nitric acid (HNO{sub 3}). The nitric acid eluate, containing the radioactive cesium, would be combined with the sludge from the waste tanks and would be converted into glass at the Defense Waste Processing Facility (DWPF) at SRS. The amount of nitric acid that would be used to elute the RF resin, using the current elution protocol, exceeds the capacity of DWPF to destroy the nitrate ions and maintain the required chemical reducing environment in the glass melt. Installing a denitration evaporator at SRS is technically feasible but would add considerable cost to the project. Alternate methods for eluting the resin have been tested, including using lower concentrations of nitric acid, other acids, and changing the flow regimes. About 4 BV of 0.5 M HNO{sub 3} are required to remove the sodium (titrate the resin) and most of the cesium from the resin, so the bulk of the acid used for the baseline elution method removes a very small quantity of cesium from the resin. A summary of the elution methods that have been tested are listed.

Taylor, Paul Allen [ORNL; Johnson, Heather Lauren [University of Tennessee, Knoxville (UTK)

2009-02-01

389

Synthesis of improved phenolic resins  

NASA Technical Reports Server (NTRS)

Twenty seven addition cured phenolic resin compositions were prepared and tested for their ability to give char residues comparable to state-of-the-art phenolic resins. Cyanate, epoxy, allyl, acrylate, methacrylate and ethynyl derivatized phenolic oligomers were investigated. The novolac-cyanate and propargyl-novolac resins provided anaerobic char yields at 800 C of 58 percent. A 59 percent char yield was obtained from modified epoxy novolacs. A phosphonitrilic derivative was found to be effective as an additive for increasing char yields. The novolac-cyanate, epoxy-novolac and methacrylate-epoxy-novolac systems were investigated as composite matrices with Thornel 300 graphite fiber. All three resins showed good potential as composite matrices. The free radical cured methacrylate-epoxy-novolac graphite composite provided short beam shear strengths at room temperature of 93.3 MPa (13.5 ksi). The novolac-cyanate graphite composite produced a short beam shear strength of 74 MPa (10.7 ksi) and flexural strength of 1302 MPa (189 ksi) at 177 C. Air heat aging of the novolac-cyanate and epoxy novolac based composites for 12 weeks at 204 C showed good property retention.

Delano, C. B.; Mcleod, A. H.

1979-01-01

390

Polyesteramide-amino Resin Systems for Industrial Maintenance Coatings  

Microsoft Academic Search

Oil-modified polyesteramide resins, suitable for surface coating applications, have been synthesised, using a non-traditional semidrying niger seed oil (Guizota Olifera). N,N-bis-(2-hydroxyethyl) niger amide (HENA) has been prepared by aminolysis of the oil with diethanolamine using zinc oxide as a catalyst. HENA was reacted separately with both phthalic anhydride (PA) and isophthalic acid (IPA) in varying molar ratios to obtain two

T. K. Roy; V. M. Mannari; D. A. Raval

1998-01-01

391

Aliphatic polycarbonate resins for radiation curable powder coatings  

Microsoft Academic Search

Thermosetting resins based on semi-crystalline poly(dimethyl trimethylene carbonate) (PDTC) were synthesised and characterised. Polymers with linear and branched architectures were synthesised through cationic ring opening polymerisation (CROP) of dimethyl trimethylene carbonate (DTC) using a series of polyols as initiators and fumaric acid as catalyst. The best powders were stable during storage at 45°C for one week and could subsequently form

Peter Löwenhielm; Daniel Nyström; Mats Johansson; Anders Hult

2005-01-01

392

Method of recovering hazardous waste from phenolic resin filters  

DOEpatents

The invention is a process for the recovery of hazardous wastes such as heavy metals and radioactive elements from phenolic resin filter by a circulating a solution of 8 to 16 molar nitric acid at a temperature of 110 to 190 degrees F. through the filter. The hot solution dissolves the filter material and releases the hazardous material so that it can be recovered or treated for long term storage in an environmentally safe manner.

Meikrantz, David H. (Idaho Falls, ID); Bourne, Gary L. (Idaho Falls, ID); McFee, John N. (Albuquerque, NM); Burdge, Bradley G. (Idaho Falls, ID); McConnell, Jr., John W. (Idaho Falls, ID)

1991-01-01

393

Diclofenac removal in urine using strong-base anion exchange polymer resins.  

PubMed

One of the major sources of pharmaceuticals in the environment is wastewater effluent of which human urine contributes the majority of pharmaceuticals. Urine source separation has the potential to isolate pharmaceuticals at a higher concentration for efficient removal as well as produce a nutrient byproduct. This research investigated the efficacy of using strong-base anion exchange polymer resins to remove the widely detected and abundant pharmaceutical, diclofenac, from synthetic human urine under fresh and ureolyzed conditions. The majority of experiments were conducted using a strong-base, macroporous, polystyrene resin (Purolite A520E). Ion-exchange followed a two-step removal rate with rapid removal in 1 h and equilibrium removal in 24 h. Diclofenac removal was >90% at a resin dose of 8 mL/L in both fresh and ureolyzed urine. Sorption of diclofenac onto A520E resin was concurrent with desorption of an equivalent amount of chloride, which indicates the ion-exchange mechanism is occurring. The presence of competing ions such as phosphate and citrate did not significantly impact diclofenac removal. Comparisons of three polystyrene resins (A520E, Dowex 22, Dowex Marathon 11) as well as one polyacrylic resin (IRA958) were conducted to determine the major interactions between anion exchange resin and diclofenac. The results showed that polystyrene resins provide the highest level of diclofenac removal due to electrostatic interactions between quaternary ammonium functional groups of resin and carboxylic acid of diclofenac and non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Diclofenac was effectively desorbed from A520E resin using a regeneration solution that contained 4.5% (m/m) NaCl in an equal-volume mixture of methanol and water. The greater regeneration efficiency of the NaCl/methanol-water mixture over the aqueous NaCl solution supports the importance of non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Experiments with ketoprofen, in addition to diclofenac, suggest that polystyrene anion exchange resins can be used to selectively remove other acidic pharmaceuticals from urine. PMID:24029637

Landry, Kelly A; Boyer, Treavor H

2013-11-01

394

Chemically modified polymeric resins for solid-phase extraction and group separation prior to analysis by liquid or gas chromatography  

SciTech Connect

Polystyrene divinylbenzene was modified by acetyl, sulfonic acid, and quaternary ammonium groups. A resin functionalized with an acetyl group was impregnated in a PTFE membrane and used to extract and concentrate phenolic compounds from aqueous samples. The acetyl group created a surface easily wetted, making it an efficient adsorbent for polar compounds in water. The membrane stabilized the resin bed. Partially sulfonated high surface area resins are used to extract and group separate an aqueous mixture of neutral and basic organics; the bases are adsorbed electrostatically to the sulfonic acid groups, while the neutraons are adsorbed hydrophobically. A two-step elution is then used to separate the two fractions. A partially functionalized anion exchange resin is used to separate organic acids and phenols from neutrals in a similar way. Carboxylic acids are analyzed by HPLC and phenols by GC.

Schmidt, L.W.

1993-07-01

395

EVALUATION OF METHODS FOR THE ISOLATION OR CONCENTRATION OF ORGANIC SUBSTANCES FROM WATER USING XAD-4 QUATERNARY RESIN  

EPA Science Inventory

A synthetic resin (Amberlite XAD-4 Quaternary in the OH- form) was evaluated as an adsorption medium for the concentration/isolation of acids, amines, aldehydes, carbohydrates, chlorobiphenyls, esters, hydrocarbons, ketones, phenols, polynuclear aromatic hydrocarbons, and trihalo...

396

Chemically modified polymeric resins for solid-phase extraction and group separation prior to analysis by liquid or gas chromatography.  

National Technical Information Service (NTIS)

Polystyrene divinylbenzene was modified by acetyl, sulfonic acid, and quaternary ammonium groups. A resin functionalized with an acetyl group was impregnated in a PTFE membrane and used to extract and concentrate phenolic compounds from aqueous samples. T...

L. W. Schmidt

1993-01-01

397

Vinylstyrylpyridine-modified bismaleimide composite resins  

NASA Technical Reports Server (NTRS)

Vinylstilbazole (vinylstyrylpyridine) and vinylpolystyrylpyridine was prepared for the purpose of modifying bismaleimide composite resins. Cure studies of resin systems were investigated by differential scanning calorimetry. The vinylstyrylpyridine-modified bismaleimide composite resins were found to have lower cure and gel temperatures, and shorter cure times than the corresponding unmodified composite resins. The resin systems were reinforced with commercially available satin-weave carbon cloth fabricated by hot melt (or solvent) techniques. Thermal stability, flammability, moisture absorption, and mechanical properties of the composites (such as flexural strength, modulus, tensile and short beam shear strength) were determined. Composite laminates showed substantial improvements in both processability and mechanical properties compared to the bismaleimide control systems.

Hsu, M.-T. S.; Chen, T. S.; Parker, J. A.; Heimbuch, A. H.

1984-01-01

398

Contemporary denture base resins: Part 2.  

PubMed

Provision of partial and complete dentures constructed from resin is commonplace and a satisfactory outcome requires the consideration of the properties of the resin, the oral tissues and prosthodontic principles. This second of a two-part series examines the advantages and disadvantages of flexible nylon denture base resins, which have found popularity for the provision of partial dentures. Adverse effects of denture base resins are examined and the benefits and shortcomings of softliners are explored. Chairside adjustment and polishing, and denture hygiene are also discussed. Clinical Relevance: Knowledge of contemporary denture base resin systems will help to achieve optimal outcomes in removable prosthodontics. PMID:22675889

Rickman, Luke J; Padipatvuthikul, Pavinee; Satterthwaite, Julian D

2012-04-01

399

A Method for Characterizing PMR-15 Resin  

NASA Technical Reports Server (NTRS)

Quantitative analysis technique based on reverse-phase, highperformance liquid chromatography (HPLC) and paired-ion chromatography (PIC) developed for PMR-15 resins. In reverse-phase HPLC experiment, polar solvent containing material to be analyzed passed through column packed with nonpolar substrate. Composition of PMR-15 Resin of 50 weight percent changes as resin ages at room temperature. Verification of proper resin formulation and analysis of changes in resin composition during storage important to manufacturers of PMR-15 polymer matrix composite parts. Technique especially suitable for commercial use by manufacturers of high-performance composite components.

Roberts, G. D.; Lauver, R. W.

1986-01-01

400

High Temperature VARTM of Phenylethynyl Terminated Imides (PETI) Resins  

NASA Technical Reports Server (NTRS)

Fabrication of composite structures using vacuum assisted resin transfer molding (VARTM) is generally more affordable than conventional autoclave techniques. Recent efforts have focused on adapting VARTM for the fabrication of high temperature composites. Due to their low melt viscosity and long melt stability, certain phenylethynyl terminated imides (PETI) can be processed into composites using high temperature VARTM (HT-VARTM). However, one of the disadvantages of the current HT-VARTM resin systems has been the high porosity of the resultant composites. For aerospace applications a void fraction of less than 2% is desired. In the current study, two PETI resins, LARCTM PETI-330 and LARCTM PETI-8 have been used to fabricate test specimens using HT-VARTM. The resins were infused into carbon fiber preforms at 260 C and cured between 316 C and 371 C. Modifications to the thermal cycle used in the laminate fabrication have reduced the void content significantly (typically < 3%) for carbon fiber biaxially woven fabric. Photomicrographs of the panels were taken and void contents were determined by acid digestion. For carbon fiber uniaxial fabric, void contents of less than 2% have been obtained using both PETI-8 and PETI-330. Mechanical properties of the panels were determined at both room and elevated temperatures. These include short beam shear and flexure tests. The results of this work are presented herein.

Ghose, Sayata; Cano, Roberto J.; Britton, Sean M.; Watson, Kent A.; Jensen, Brian J.; Connell, John W.

2010-01-01

401

Bond strength of fiber-reinforced composite resin restorations.  

PubMed

Severe tooth wear is common in older dentate individuals, with one treatment option being composite resin restorations reinforced with a suitable matrix. This study evaluated the use of high modulus polyethylene (Celanese) fibers as a reinforcing matrix for composite resin. Human mandibular incisor teeth were sectioned to simulate severe tooth wear. Sectioned surfaces were measured, the teeth paired and assigned to control or test sample groups, and further assigned to be tested with a labial or lingual shearing force. A phosphorylated dentin bonding adhesive was applied to the abraded dentin surface. Labial and lingual intra-enamel bevel preparations were cut on each specimen. A piece of Celanese fabric was bonded onto the acid-etched labial and lingual bevels of the test specimens using an enamel bonding agent. Class IV composite resin restorations were then placed onto the test and control specimens. Following water storage, the specimens were subjected to shearing forces. Bond strengths for test specimens were significantly greater (p < 0.03) than the controls. Specimens with a labially applied force also had significantly higher bond strengths (p < 0.001). SEM analysis revealed adhesive bond failures over dentin surfaces, with cohesive bond failures within the composite resin. Celanese fibers maintained the restorations on the teeth, although adhesive failures were seen between the fibers and enamel bonding agent. PMID:1419220

Galan, D; Lynch, E; Heath, M R

1992-01-01

402

Alkylation of phenol with MTBE and other tert-butyl ethers: cation exchange resins as catalysts  

Microsoft Academic Search

Alkylation of phenol was carried out using methyl tert-butyl ether, mono tert-butyl ether of mono ethylene glycol, tert-butanol and isobutylene in the presence of cation exchange resins, acid treated clay and para-toluene sulfonic acid as catalysts. The selectivity with respect to 2- and 4-tert-butyl phenol was studied.

K. Gokul Chandra; M. M. Sharma

1993-01-01

403

The use of extraction chromatography resins to concentrate actinides and strontium from soil for radiochromatographic analyses  

Microsoft Academic Search

An analytical technique utilizing selective extractant resins to concentrate strontium and actinides from soil followed by separation with radiochromatography was evaluated. The technique was tested using uncontaminated soil samples spiked with a radionuclide tracer solution that were either microwave-aided acid digested or leached with a strong acid. Extraction of the strontium and actinides from the acidified solution was accomplished using

J. E. Roane; T. A. DeVol; J. D. Leyba; R. A. Fjeld

2003-01-01

404

Analysis of diterpenoic compounds in natural resins applied as binders in museum objects by capillary electrophoresis  

Microsoft Academic Search

The exudates of conifers consist mainly of diterpenoic acids of the abietane and pimarane type (abietic, neoabietic, dehydroabietic, palustric, pimaric, isopimaric, levopimaric and sandaracopimaric acid) and larixol acetate. These natural resins were used as adhesives, coatings, varnishes or plasticizers in artistic and historic works since ancient times. For the purpose of conservation and restoration and for art historic examination of

Anna Findeisen; Viliam Kolivoska; Isabella Kaml; Wolfgang Baatz; Ernst Kenndler

2007-01-01

405

Serum proteins and enzymes in pregnant rats treated with epoxy resin or triethylenetetraamine stabilizer  

Microsoft Academic Search

A study was made of the serum and amniotic fluid levels of several acute phase reactants (seromucoid, haptoglobin, and sialic acid) and enzymatic activities (lactate dehydrogenase, leucylnaphthylamidase, ?-glutamyltranspeptidase, aminotransferases, cholmesterase, and alkaline and acid phosphatases) in pregnant and nonpregnant rats treated with epoxy resin Epidian 5 or triethylenetetraamine stabilizer. Changes produced by the action of the chemicals were similar, including

W. Dobryszycka; M. Warwas; A. Woytofi; J. Woyto?; J. Szacki

1974-01-01

406

BENCH SCALE EVALUATION OF RESINS AND ACTIVATED CARBONS FOR WATER PURIFICATION  

EPA Science Inventory

Adsorption isotherms and bench scale column studies were used to compare the performance of five types of commercially available activated carbon and four types of resin for the removal of humic acids, fulvic acids, 2-methylisoborneol (MIB), and chloroform from water. For the ads...

407

Tensile bond strength of Er,Cr:YSGG laser-irradiated human dentin and analysis of dentin–resin interface  

Microsoft Academic Search

ObjectivesAs the bond strength of composite resin to Er,Cr:YSGG laser-irradiated dentin has not yet been evaluated, the objectives of this study were to investigate the tensile bond strength and to analyze the resin–dentin interface among bur-cut\\/acid-etched, Er,Cr:YSGG laser-ablated\\/acid-etched and Er,Cr:YSGG laser-ablated human dentin.

Bor-Shiunn Lee; Po-Yen Lin; Min-Huey Chen; Tseng-Ting Hsieh; Chun-Pin Lin; Juin-Yih Lai; Wan-Hong Lan

2007-01-01

408

Effect of dissolved organic matter on nitrate-nitrogen removal by anion exchange resin and kinetics studies.  

PubMed

The effects of dissolved organic matter (DOM) on the removal of nitrate-nitrogen from the model contaminated water have been investigated utilizing the strong base anion exchange resins. With the increase of gallic acid concentration from 0 to 400 mg/L, the adsorption amount of nitrate-nitrogen on the commercial resins, including D201, Purolite A 300 (A300) and Purolite A 520E (A520E), would significantly decrease. However, the presence of tannin acid has little impact on nitrate-nitrogen adsorption on them.Compared to D201 and A300 resins, A520E resin exhibited more preferable adsorption ability toward nitrate-nitrogen in the presence of competing organic molecules, such as gallic acid and tannin acid at greater levels in aqueous solution. Attractively, the equilibrium data showed that the adsorption isotherm of nitrate-nitrogen on A520E resin was in good agreement with Langmuir and Freundlich equations. The rate parameters for the intra particle diffusion have been estimated for the different initial concentrations. In batch adsorption processes, nitrate-nitrogen diffuse in porous adsorbent and rate process usually depends on t1/2 rather than the contact time. The pseudo first- and the second-order kinetic models fit better for nitrate-nitrogen adsorption onto A520E resin. The observations reported herein illustrated that A520E resin will be an excellent adsorbent for enhanced removal of nitrate-nitrogen from contaminated groundwater. PMID:23586305

Song, Haiou; Yao, Zhijian; Wang, Mengqiao; Wang, Jinnan; Zhu, Zhaolian; Li, Aimin

2013-01-01

409

Synthesis and swelling properties of ?-cyclodextrin-based superabsorbent resin with network structure.  

PubMed

A biodegradable, ?-cyclodextrin-based superabsorbent resin was synthesized by the inverse suspension method. The microstructure, chemical structure, and thermal performance of the resin were characterized by scanning electron microscopy, Fourier transform-infrared spectroscopy, and differential scanning calorimetry. The effects of the synthesis conditions (dosage of cross-linking agent, mass ratios of acrylic acid to acrylamide, mass ratios of ?-cyclodextrin to total monomer, neutralization degree, initiator dosage, and reaction time) were optimized to achieve a resin with a maximum swelling capacity. The water absorbency of the optimized resin in distilled water was 1544.76 g/g and that in 0.9 wt.% NaCl was 144.52 g/g. The resin, which is thermoplastic as well as pH-sensitive, had good salt resistance and underwent a maximum in swelling with time in CaCl(2) and AlCl(3) solutions. The fracture surface of the dry resin contained many pores. After swelling, the internal hydrogel showed a typical three-dimensional network structure. The biodegradation of the resin reached 71.2% after 18 days treatment at 30 °C with Lentinus edodes. PMID:23399293

Huang, Zhanhua; Liu, Shouxin; Fang, Guizhen; Zhang, Bin

2013-02-15

410

Sorption and desorption of perchlorate and U(VI) by strong-base anion-exchange resins.  

PubMed

This study investigated the sorption affinity and capacity of six strong-base anion-exchange (SBA) resins for both uranium [U(VI)] and perchlorate (ClO4-) in simulated groundwater containing varying concentrations of sulfate (SO4(2-)). Additionally, desorption of U(VI) from spent resins was studied to separate U(VI) from resins with sorbed ClO4- for waste segregation and minimization. Results indicate that all SBA resins investigated in this study strongly sorb U(VI). The gel-type polyacrylic resin (Purolite A850) showed the highest sorption affinity and capacityfor U(VI) butwasthe least effective in sorbing ClO4-. The presence of SO4(2-) had little impact on the sorption of U(VI) but significantly affected the sorption of ClO4-, particularly on monofunctional SBA resins. A dilute acid wash was found to be effective in desorbing U(VI) but ineffective in desorbing ClO4- from bifunctional resins (Purolite A530E and WBR109). A single wash removed approximately 75% of sorbed U(VI) but only approximately 0.1% of sorbed ClO4- from the bifunctional resins. On the other hand, only 21.4% of sorbed U(VI) but approximately 34% of sorbed ClO4- was desorbed from the Purolite A850 resin. This study concludes that bifunctional resins could be used effectively to treatwater contaminated with ClO4- and traces of U(VI), and dilute acid washes could minimize hazardous wastes by separating sorbed U(VI) from ClO4- prior to the regeneration of the spent resin loaded with ClO4-. PMID:15757357

Gu, Baohua; Ku, Yee-Kyoung; Brown, Gilbert M

2005-02-01

411

Foam, Foam-resin composite and method of making a foam-resin composite  

NASA Technical Reports Server (NTRS)

This invention relates to a foam, a foam-resin composite and a method of making foam-resin composites. The foam set forth in this invention comprises a urethane modified polyisocyanurate derived from an aromatic amino polyol and a polyether polyol. In addition to the polyisocyanurate foam, the composite of this invention further contains a resin layer, wherein the resin may be epoxy, bismaleimide, or phenolic resin. Such resins generally require cure or post-cure temperatures of at least 350.degree. F.

Cranston, John A. (Inventor); MacArthur, Doug E. (Inventor)

1995-01-01

412

Chemical synthesis of NS-1 region of hepatitis C-viral polyprotein fragments: a comparison of PS-BDODMA resin and merrifield resin.  

PubMed

Three peptide fragments selected from the NS-1 region of hepatitis C-viral polyprotein (Leu-Ile-Asn-Thr-Asn-Ala-Ser-Trp-His-Ala-Asn-Arg-Thr-Ala-Leu-Ser Asn-Asp Ser-Lys Leu Asn Thr-Gly Ala NH(2), Leu-lle Asn Thr Asn Ala Ser-Trp-His-Ala-Asn-Arg-Thr Ala NH(2) and Leu-Asn-Cys(Acm)-Asn-Asp-Ser-Leu-Asn-Thr-Ala-NH(2)) have been synthesized on PS-BDODMA resin. The synthetic capability of the resin PS-BDODMA resin was compared with Merrifield resin. The peptides were synthesized by the stepwise fluoren-9-yl methoxycarbonyl (Fmoc) solid-phase method. The synthesized peptides were purified by HPLC and the identity of the peptides was established by mass spectrum and amino acid analysis. The synthesis of these peptides illustrates the application of the PS-BDODMA resin for the synthesis of long chain peptides in high yield and homogeneity compared to the Merrifield resin. PMID:12144521

Roice, Michael; Kumar, K Santhosh; Pillai, V N Rajasekharan

2002-06-01

413

Extraction of high quality DNA from seized Moroccan cannabis resin (Hashish).  

PubMed

The extraction and purification of nucleic acids is the first step in most molecular biology analysis techniques. The objective of this work is to obtain highly purified nucleic acids derived from Cannabis sativa resin seizure in order to conduct a DNA typing method for the individualization of cannabis resin samples. To obtain highly purified nucleic acids from cannabis resin (Hashish) free from contaminants that cause inhibition of PCR reaction, we have tested two protocols: the CTAB protocol of Wagner and a CTAB protocol described by Somma (2004) adapted for difficult matrix. We obtained high quality genomic DNA from 8 cannabis resin seizures using the adapted protocol. DNA extracted by the Wagner CTAB protocol failed to give polymerase chain reaction (PCR) amplification of tetrahydrocannabinolic acid (THCA) synthase coding gene. However, the extracted DNA by the second protocol permits amplification of THCA synthase coding gene using different sets of primers as assessed by PCR. We describe here for the first time the possibility of DNA extraction from (Hashish) resin derived from Cannabis sativa. This allows the use of DNA molecular tests under special forensic circumstances. PMID:24124454

El Alaoui, Moulay Abdelaziz; Melloul, Marouane; Alaoui Amine, Sanaâ; Stambouli, Hamid; El Bouri, Aziz; Soulaymani, Abdelmajid; El Fahime, Elmostafa

2013-01-01

414

Resin registration for interocclusal records.  

PubMed

An ideal material for registering interocclusal records should (1) have reproductive accuracy, (2) be easy to handle, (3) offer no resistance to closure during the registration, (4) be rigid when set, and (5) have a fair degree of hardness when set. The acrylic resin, Duralay, has these qualities. Techniques for utilizing Duralay to register interocclusal records for unilateral restorations, bilateral restorations, full-arch restorations, as well as fixed and removable restorations in the same arch have been demonstrated. PMID:319224

Skurnik, H

1977-02-01

415

Phosphorus-containing imide resins  

NASA Technical Reports Server (NTRS)

Flame-resistant reinforced bodies are disclosed which are composed of reinforcing fibers, filaments or fabrics in a cured body of bis- and tris-imide resins derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, or of addition polymers of such imides, including a variant in which a mono-imide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride.

Varma, I. K.; Fohlen, G. M.; Parker, J. A. (inventors)

1984-01-01

416

Regeneration of strong-base anion-exchange resins by sequential chemical displacement  

DOEpatents

A method for regenerating strong-base anion exchange resins utilizing a sequential chemical displacement technique with new regenerant formulation. The new first regenerant solution is composed of a mixture of ferric chloride, a water-miscible organic solvent, hydrochloric acid, and water in which tetrachloroferrate anion is formed and used to displace the target anions on the resin. The second regenerant is composed of a dilute hydrochloric acid and is used to decompose tetrachloroferrate and elute ferric ions, thereby regenerating the resin. Alternative chemical displacement methods include: (1) displacement of target anions with fluoroborate followed by nitrate or salicylate and (2) displacement of target anions with salicylate followed by dilute hydrochloric acid. The methodology offers an improved regeneration efficiency, recovery, and waste minimization over the conventional displacement technique using sodium chloride (or a brine) or alkali metal hydroxide.

Brown, Gilbert M. (Knoxville, TN); Gu, Baohua (Oak Ridge, TN); Moyer, Bruce A. (Oak Ridge, TN); Bonnesen, Peter V. (Knoxville, TN)

2002-01-01

417

Removal of NO by coordination to iron (II) immobilized chelate resins  

SciTech Connect

This paper reports on the equilibrium constants for coordination of NO to the resin-immobilized Fe(II) complex in an aqueous slurry and to the iminodiacetato-Fe(II) complex in an aqueous solution measured at different pHs and temperatures. The equilibrium constant in the resin phase was about 1/20th of that in the liquid phase but is still about 20 times as large as that in the absence of iminodiacetic acid. It is difficult to avoid oxidation of Fe(II) in the course of thermal regeneration of spent Fe(II) immobilized chelate resins, so it seems to be more realistic to recover only chelate resins from spent absorbent and immobilize Fe(II) again to them.

Sada, E.; Kumazawa, H.; Kayahara, H.; Hagiwara, H.; Bae, S.Y. (Dept. of Chemical Engineering, Kyoto Univ., Kyoto 606 (JP))

1990-05-01

418

Fast removal of uranium from aqueous solutions using tetraethylenepentamine modified magnetic chitosan resin.  

PubMed

Chitosan was cross-linked using glutaraldehyde in the presence of magnetite. The resin was chemically modified through the reaction with tetraethylenepentamine (TEPA) to produce amine bearing chitosan. The resin showed a higher affinity towards the uptake of UO2(2+) ions from aqueous medium: maximum sorption capacity reached 1.8 mmol g(-1) at pH 4 and 25 °C. The nature of interaction of UO2(2+) ions with the resin was identified. Kinetics were carried out at different temperatures and thermodynamic parameters were evaluated. Breakthrough curves for the removal of UO2(2+) were studied at different flow rates, bed heights and after 3 regeneration cycles. Hydrochloric acid (0.5 M) was used for desorbing UO2(2+) from loaded resin: desorption yield as high as 98% was obtained. PMID:24503051

Elwakeel, Khalid Z; Atia, Asem A; Guibal, Eric

2014-05-01

419

Evaluation of ion exchange resins for the removal of dissolved organic matter from biologically treated paper mill effluent.  

PubMed

In this study, the efficiency of six ion exchange resins to reduce the dissolved organic matter (DOM) from a biologically treated newsprint mill effluent was evaluated and the dominant removal mechanism of residual organics was established using advanced organic characterisations techniques. Among the resins screened, TAN1 possessed favourable Freundlich parameters, high resin capacity and solute affinity, closely followed by Marathon MSA and Marathon WBA. The removal efficiency of colour and lignin residuals was generally good for the anion exchange resins, greater than 50% and 75% respectively. In terms of the DOM fractions removal measured through liquid chromatography-organic carbon and nitrogen detector (LC-OCND), the resins mainly targeted the removal of humic and fulvic acids of molecular weight ranging between 500 and 1000 g mol(-1), the portion expected to contribute the most to the aromaticity of the effluent. For the anion exchange resins, physical adsorption operated along with ion exchange mechanism assisting to remove neutral and transphilic acid fractions of DOM. The column studies confirmed TAN1 being the best of those screened, exhibited the longest mass transfer zone and maximum treatable volume of effluent. The treatable effluent volume with 50% reduction in dissolved organic carbon (DOC) was 4.8 L for TAN1 followed by Marathon MSA - 3.6L, Marathon 11 - 2.0 L, 21K-XLT - 1.5 L and Marathon WBA - 1.2 L. The cation exchange resin G26 was not effective in DOM removal as the maximum DOC removal obtained was only 27%. The resin capacity could not be completely restored for any of the resins; however, a maximum restoration up to 74% and 93% was achieved for TAN1 and Marathon WBA resins. While this feasibility study indicates the potential option of using ion exchange resins for the reclamation of paper mill effluent, the need for improving the regeneration protocols to restore the resin efficiency is also identified. Similarly, care should be taken while employing LC-OCND for characterising resin-treated effluents, as the resin degradation is expected to contribute some organic carbon moieties misleading the actual performance of resin. PMID:23116827

Bassandeh, Mojgan; Antony, Alice; Le-Clech, Pierre; Richardson, Desmond; Leslie, Greg

2013-01-01

420

Induction of isoprenyl diphosphate synthases, plant hormones and defense signalling genes correlates with traumatic resin duct formation in Norway spruce (Picea abies).  

PubMed

Norway spruce (Picea abies) defends itself against herbivores and pathogens by formation of traumatic resin ducts filled with terpenoid-based oleoresin. An important group of enzymes in terpenoid biosynthesis are the short-chain isoprenyl diphosphate synthases which produce geranyl diphosphate (C(10)), farnesyl diphosphate (C(15)), and geranylgeranyl diphosphate (C(20)) as precursors of monoterpenes, sesquiterpenes, and diterpene resin acids, respectively. After treatment with methyl jasmonate (MJ) we investigated the expression of all isoprenyl diphosphate synthase genes characterized to date from Norway spruce and correlated this with formation of traumatic resin ducts and terpene accumulation. Formation of traumatic resin ducts correlated with higher amounts of monoterpenes, sesquiterpenes and diterpene resin acids and an upregulation of isoprenyl diphosphate synthase genes producing geranyl diphosphate or geranylgeranyl diphosphate. Among defense hormones, jasmonate and jasmonate-isoleucine conjugate accumulated to higher levels in trees with extensive traumatic resin duct formation, whereas salicylate did not. Jasmonate and ethylene are likely to both be involved in formation of traumatic resin ducts based on elevated transcripts of genes encoding lipoxygenase and 1-aminocyclopropane-1-carboxylic acid oxidase associated with resin duct formation. Other genes involved in defense signalling in other systems, mitogen-activated protein kinase3 and nonexpressor of pathogenesis-related gene1, were also associated with traumatic resin duct formation. These responses were detected not only at the site of MJ treatment, but also systemically up to 60 cm above the site of treatment on the trunk. PMID:22002747

Schmidt, Axel; Nagel, Raimund; Krekling, Trygve; Christiansen, Erik; Gershenzon, Jonathan; Krokene, Paal

2011-12-01

421

The influence of plutonium concentration and solution flow rate on the effective capacity of macroporous anion exchange resin. [Lewatit MP-500-FK; Pu/sup +/  

SciTech Connect

The principal aqueous process used to recover and purify plutonium at the Los Alamos Plutonium Facility is anion exchange in nitric acid. Previous studies with gel-type anion exchange resin have shown an inverse relationship between plutonium concentration in the feed solution and the optimum flow rate for this process. Because gel-type resin has been replaced with macroporous resin at Los Alamos, the relationship between plutonium concentration and solution flow rate was reexamined with the selected Lewatit MP-500-FK resin using solutions of plutonium in nitric acid and in nitric acid with high levels of added nitrate salts. Our results with this resin differ significantly from previous data obtained with gel-type resin. Flow-rate variation from 10 to 80 liters per hour had essentially no effect on the measured quantities of plutonium sorbed by the macroporous resin. However, the effect of plutonium concentration in the feed solutions was pronounced, as feed solutions that contained the highest concentrations of plutonium also produced the highest resin loadings. The most notable effect of high concentrations of dissolved nitrate salts in these solutions was an increased resin capacity for plutonium at low flow rates. 16 refs., 7 figs., 2 tabs.

Marsh, S.F.; Gallegos, T.D.

1987-07-01

422

Wear rates of resin composites.  

PubMed

SUMMARY A laboratory study was conducted to examine the wear of resin composite materials using a generalized wear simulation model. Ten specimens each of five resin composites (Esthet•X [EX], Filtek Supreme Plus [SP], Filtek Z250 [Z2], Tetric EvoCeram [EC], and Z100 Restorative [Z1]) were subjected to wear challenges of 100,000, 400,000, 800,000, and 1,200,000 cycles. The materials were placed in cylinder-shaped stainless-steel fixtures, and wear was generated using a flat stainless-steel antagonist in a slurry of polymethylmethacrylate beads. Wear (mean facet depth [?m] and volume loss [mm(3)]) was determined using a noncontact profilometer (Proscan 2000) with Proscan and ProForm software. Statistical analysis of the laboratory data using analysis of variance and Tukey's post hoc test showed a significant difference (p<0.05) for mean wear facet depth and volume loss for both the number of cycles and resin composite material. Linear regression analysis was used to develop predictive wear rates and volume loss rates. Linear wear was demonstrated with correlation coefficients (R(2)) ranging from 0.914 to 0.995. Mean wear values (mean facet depth [?m]) and standard deviations (SD) for 1200K cycles were as follows: Z1 13.9 (2.0), Z2 26.7 (2.7), SP 30.1 (4.1), EC 31.8 (2.3), and EX 67.5 (8.2). Volume loss (mm(3)) and SDs for 1200K cycles were as follows: Z1 0.248 (0.036), Z2 0.477 (0.044), SP 0.541 (0.072), EC 0.584 (0.037), and EX 1.162 (0.139). The wear rate (?m) and volume loss rate (mm(3)) per 100,000 cycles for the five resin composites were as follows: wear rate Z1 0.58, EC 1.27, Z2 1.49, SP 1.62, and EX 4.35, and volume loss rate Z1 0.009, EC 0.024, Z2 0.028, SP 0.029, and EX 0.075. The generalized wear model appears to be an excellent method for measuring relative wear of resin composite materials. PMID:22856679

Barkmeier, W W; Erickson, R I; Latta, M A; Wilwerding, T M

2013-01-01

423

Decomposition of ion exchange resins by pyrolysis  

SciTech Connect

Pyrolysis of spent ion exchange resins is one of the most effective methods for reducing radioactive waster volume and for making the final waste form more stable. Fundamental experiments were performed to clarify the pyrolysis characteristics of anion and cation exchange resins. Residual elemental analyses and off-gas analyses showed that the decomposition ratio of cation resins was only 50 wt% at 600/sup 0/C, while that of anion resins was 90 wt% at 400/sup 0/C. Infrared spectroscopy for cation resins attributed its low decomposition ratio to formation of a highly heat-resistant polymer (sulfur bridged) during pyrolysis. Measurements of residual hygroscopicity and cement package strength indicated that the optimum pyrolysis temperatures for preventing resins swelling and package expansion were between 300 and 500/sup 0/C.

Matsuda, M.; Funabashi, K.; Nishi, T.; Yusa, H.; Kikuchi, M.

1986-11-01

424

Development of tough, moisture resistant laminating resins  

NASA Technical Reports Server (NTRS)

Tough, moisture resistant laminating resins for employment with graphite fibers were developed. The new laminating resins exhibited cost, handleability and processing characteristics equivalent to 394K (250 F) curing epoxies. The laminating resins were based on bisphenol A dicyanate and monofunctional cyanates with hydrophobic substituents. These resins sorb only small quantities of moisture at equilibrium (0.5% or less) with minimal glass transition temperature depression and represent an improvement over epoxies which sorb around 2% moisture at equilibrium. Toughening was accomplished by the precipitation of small diameter particles of butadiene nitrile rubber throughout the resin matrix. The rubber domains act as microcrack termini and energy dissipation sites, allowing increased stress accommodation prior to catastrophic failure. A unique blend of amine terminated butadiene nitrile elastomer (MW 2,000) and a high nitrile content butadiene nitrile rubber yielded the desired resin morphology.

Brand, R. A.; Harrison, E. S.

1982-01-01

425

Pharmaceutical Applications of Ion-Exchange Resins  

Microsoft Academic Search

The historical uses of ion-exchange resins and a summary of the basic chemical principles involved in the ion-exchange process are discussed. Specific applications of ion-exchange resins are provided. The utility of these agents to stabilize drugs are evaluated. Commonly occurring chemical and physical incompatibilities are reviewed. Ion-exchange resins have found applicability as inactive pharmaceutical constituents, particularly as disintegrants (inactive tablet

David P. Elder

2005-01-01

426

RADIATION STABILITY OF ION EXCHANGE RESINS  

Microsoft Academic Search

the structure of the micromolecular framework, the chemical nature, the ; exchange group, the type of crosslinkage and the radiation medium. Both in DVB-; styrene copolymers and in phenol-formaldehyde resins the C--R bond (KF-1 and RF ; resins) was more resistant towards ionizing radiation than the C--S bond (KU-2, ; KU-1 resins). By changing the structure of the crosslinking component

E. D. Kiseleva; K. V. Chmutov; V. N. Krupnova

1962-01-01

427

Radiation testing of organic ion exchange resins  

Microsoft Academic Search

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of ¹³⁷Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by

C. D. Carlson; L. A. Bray; S. A. Bryan

1995-01-01

428

Porous Ceramic Spheres from Ion Exchange Resin  

NASA Technical Reports Server (NTRS)

A commercial cation ion exchange resin, cross-linked polystyrene, has been successfully used as a template to fabricate 20 to 50 micron porous ceramic spheres. Ion exchange resins have dual template capabilities. Pore architecture of the ceramic spheres can be altered by changing the template pattern. Templating can be achieved by utilizing the internal porous structure or the external surface of the resin beads. Synthesis methods and chemical/physical characteristics of the ceramic spheres will be reported.

Dynys, Fred

2005-01-01

429

Solid phase synthesis of tertiary amines on amide REM resins: Grignard and metal hydride compatible resins.  

PubMed

Four new amide REM resins (AM REM 2-5) are described, and their use is illustrated for the synthesis of tertiary amines 6-9 and 13-16. Amide REM resins 4 and 5, which have a phenyl ring attached to the amide nitrogen, are found to give superior product yields and purities, and the resins are stable to a wider range of reagents and conditions compared to REM resin 1. PMID:11029176

Plater, M J; Murdoch, A M; Morphy, J R; Rankovic, Z; Rees, D C

2000-01-01

430

Seasonal Variation and Resin Composition in the Andean Tree Austrocedrus chilensis.  

PubMed

Little is known about the changes in resin composition in South American gymnosperms associated with the different seasons of the year. The diterpene composition of 44 resin samples from seven Austrocedrus chilensis (Cupressaceae) trees, including male and female individuals, was investigated in three different seasons of the year (February, June and November). Twelve main diterpenes were isolated by chromatographic means and identified by gas chromatography-mass spectrometry and nuclear magnetic resonance (NMR). The diterpene composition was submitted to multivariate analysis to find possible associations between chemical composition and season of the year. The principal component analysis showed a clear relation between diterpene composition and season. The most characteristic compounds in resins collected in summer were Z-communic acid (9) and 12-oxo-labda-8(17),13E-dien-19 oic acid methyl ester (10) for male trees and 8(17),12,14-labdatriene (7) for female trees. For the winter samples, a clear correlation of female trees with torulosic acid (6) was observed. In spring, E-communic acid (8) and Z-communic acid (9) were correlated with female trees and 18-hydroxy isopimar-15-ene (1) with male tree resin. A comparison between percent diterpene composition and collection time showed p < 0.05 for isopimara-8(9),15-diene (2), sandaracopimaric acid (4), compound (7) and ferruginol (11). PMID:24853713

Olate, Verónica Rachel; Soto, Alex; Schmeda-Hirschmann, Guillermo

2014-01-01

431

Etching conditions for resin-modified glass ionomer cement for orthodontic brackets.  

PubMed

This study reports the tensile bond strength of orthodontic eyelets (RMO, Inc, Denver, Colo) bonded to human extracted teeth with a resin-modified glass ionomer cement (RMGIC) (Fuji Ortho LC, GC America, Alsip, Ill) and various acid etchants (Etch-37 and All-Etch, Bisco, Schaumburg, Ill; Ultra Etch, 3M Unitek, St Paul, Minn) for enamel preparation before bonding. The enamel etch conditions were as follows: 37% phosphoric acid with silica; 37% phosphoric acid, silica-free; 10% phosphoric acid, silica-free; 10% polyacrylic acid; and unetched enamel. Bond strength was measured by pulling in tension on the eyelet with a 0.018-in steel wire perpendicular to the enamel surface with a testing machine (Instron model 1125, Canton, Mass) at a speed of 2 mm/min. A light-cured resin cement (Transbond XT, 3M Unitek, Monrovia, Calif) applied to enamel etched with 37% phosphoric acid containing silica served as a control. Each group included 30 specimens. The Weibull distribution (m) was used for statistical analysis with a 90% CI. The different etchants used with RMGIC did not affect tensile bond strength. The resin cement group had the highest tensile strength. Significantly lower bond strengths were observed when glass ionomer cement was used to bond orthodontic attachments to nonetched teeth. However, unlike resin cement, RMGIC can bond effectively to etched teeth in a moist environment without an additional bonding agent. PMID:12045770

Valente, Rudolfo M; De Rijk, Waldemar G; Drummond, James L; Evans, Carla A

2002-05-01

432

Characterization of PMR polyimide resin and prepreg  

NASA Technical Reports Server (NTRS)

Procedures for the chemical characterization of PMR-15 resin solutions and graphite-reinforced prepregs were developed, and a chemical data base was established. In addition, a basic understanding of PMR-15 resin chemistry was gained; this was translated into effective processing procedures for the production of high quality graphite composites. During the program the PMR monomers and selected model compounds representative of postulated PMR-15 solution chemistry were acquired and characterized. Based on these data, a baseline PMR-15 resin was formulated and evaluated for processing characteristics and composite properties. Commercially available PMR-15 resins were then obtained and chemically characterized. Composite panels were fabricated and evaluated.

Lindenmeyer, P. H.; Sheppard, C. H.

1984-01-01

433

Microbiological study of water-softener resins.  

PubMed

Microbial identification using effluents backflushed from exhausted urban and rural tank resins and cleaned resins containing the sulfonated copolymer of styrene and divinylbenzene (SDB) were completed, along with microbial assessment of the concentrated stock salt brine. Forty-four different bacterial and fungal genera were identified. Extensive biochemical and animal virulence tests completed on one of the six bacterial salt brine isolates indicated a pathogenic staphylococcal strain. The retention of Staphylococcus aureus, a Flavobacterium sp, and Escherichia coli B bacteriophage was demonstrated both by using the nonexhausted sodium-regenerated resin and by using the same resin exchanged with different mono-, di-, and trivalent cations. Effluent counts completed after bacterial seepage through the resins indicated the Pb(++) exchanged resin removed 55% of the bacteria; Na(+), Fe(++), and Al(+++) removed 31 to 36% and Ca(++) and Cu(++) removed about 10 to 15%. Seventy per cent or more of the bacteriophage was removed by Fe(++), Cu(++), and Al(+++), whereas the Ca(++) and Na(++) cations removed 25 to 31%. Over a 77-day period, nonsterile tap water was passed through bacterial seeded and uninoculated SDB (Na) resin columns. Effluent and resin elution counts demonstrated the growth and survival of 2 different bacteria per column. Increased bacterial retention, survival, and multiplication occurred concomitantly with accumulation of organic and inorganic materials and the Ca(++) and Mg(++) cations from the tap water. Furthermore, microbial elution from resin particles taken from column depths of 1, 8, and 16 cm indicated a bacterial diminution with increasing depths. PMID:5373675

Stamm, J M; Engelhard, W E; Parsons, J E

1969-09-01

434

Microbiological Study of Water-Softener Resins  

PubMed Central

Microbial identification using effluents backflushed from exhausted urban and rural tank resins and cleaned resins containing the sulfonated copolymer of styrene and divinylbenzene (SDB) were completed, along with microbial assessment of the concentrated stock salt brine. Forty-four different bacterial and fungal genera were identified. Extensive biochemical and animal virulence tests completed on one of the six bacterial salt brine isolates indicated a pathogenic staphylococcal strain. The retention of Staphylococcus aureus, a Flavobacterium sp, and Escherichia coli B bacteriophage was demonstrated both by using the nonexhausted sodium-regenerated resin and by using the same resin exchanged with different mono-, di-, and trivalent cations. Effluent counts completed after bacterial seepage through the resins indicated the Pb++ exchanged resin removed 55% of the bacteria; Na+, Fe++, and Al+++ removed 31 to 36% and Ca++ and Cu++ removed about 10 to 15%. Seventy per cent or more of the bacteriophage was removed by Fe++, Cu++, and Al+++, whereas the Ca++ and Na++ cations removed 25 to 31%. Over a 77-day period, nonsterile tap water was passed through bacterial seeded and uninoculated SDB (Na) resin columns. Effluent and resin elution counts demonstrated the growth and survival of 2 different bacteria per column. Increased bacterial retention, survival, and multiplication occurred concomitantly with accumulation of organic and inorganic materials and the Ca++ and Mg++ cations from the tap water. Furthermore, microbial elution from resin particles taken from column depths of 1, 8, and 16 cm indicated a bacterial diminution with increasing depths.

Stamm, John M.; Engelhard, Warren E.; Parsons, James E.

1969-01-01

435

Graphite composites with advanced resin matrices  

NASA Technical Reports Server (NTRS)

The effect of processing variables on the flammability and mechanical properties for state-of-the-art and advanced resin matrices for graphite composites were studied. Resin matrices which were evaluated included state-of-the-art epoxy, phenolic-novolac, phenolic-xylok, two types of bismaleimides, benzyl, polyethersulfone, and poly(p-phenylene sulfone). Comparable flammability and thermochemical data on graphite-reinforced laminates prepared with these resin matrices are presented, and the relationship of some of these properties to the anaerobic char yield of the resins is described.

Kourtides, D. A.

1980-01-01

436

Flexible heat resistant neutron shielding resin  

NASA Astrophysics Data System (ADS)

A flexible heat resistant neutron shielding material has been developed, which consists of polymer resin with 1 wt% boron. The neutron shielding performance of the developed resin, examined by the 252Cf neutron source, is almost the same as that of the polyethylene. The outgas of H 2, H 2O, CO and CO 2 from the resin have been measured at ˜250 °C environment. The resin will be applied around the port of the vacuum vessel as an additional shielding material and reduce the neutron streaming from a superconducting tokamak device such as JT-60SA.

Sukegawa, Atsuhiko M.; Anayama, Yoshimasa; Okuno, Koichi; Sakurai, Shinji; Kaminaga, Atsushi

2011-10-01

437

Diphonix: A new ion exchange resin for the treatment of industrial waste streams, contaminated groundwaters, and mixed-wastes  

SciTech Connect

The resin contains geminally substituted diphosphonic acid functional groups; it is synthesized by copolymerization of a tetralkylvinylidene diphosphonate with styrene, divinylbenzene, and acrylonitrile, followed by deesterifaction by refluxing with conc. HCl (the nitrile group is hydrolyzed to a carboxylic acid). The diphosphonic acid functional dominates the resin behavior toward metal ions; it has strong affinity for actinides in all oxidation states, even in 10 M HNO{sub 3} and high salt concentrations. (Efficient agents for stripping actinides from Diphonix all have a strong complexing agent containing the gem-diphosphonic acid functionality.) Diphonix can also remove heavy, toxi metals in high salt concentrations. 4 figs, 2 tabs.

Horwitz, E.P.

1994-03-01

438

Different surface preparation techniques of porcelain repaired with composite resin and fracture resistance  

PubMed Central

Background: Porcelain from prosthesis such as crown or bridge can be fractured if exposed to trauma; and, can be repaired at chairside using composite resin. Aim: To investigate the fracture resistance of few techniques of surface preparation in repairing fractured porcelain using composite resin. Materials and Methods: Eighty samples of porcelain blocks were divided into 4 groups for different surface preparations, such as, Cimara repairing kit; porcelain etch kit containing hydrofluoric acid; Panavia F resin cement; and, sandblasting using aluminium oxide, before composite resin (Filtek Z250, 3M ESPE) was bonded to the prepared porcelain blocks. Twenty others samples in the control group comprised of pure porcelain blocks. The fracture resistance of each sample was tested using Instron machine (UK). Results: With the exception of the group repaired using hydrofluoric acid (3.04±1.04 Mpa), all the other groups showed significant difference in the fracture resistance values when compared to the control group (3.05 ± 1.42 MPa) at P<0.05. Conclusions: Etching of the porcelain blocks with hydrofluoric acid holds promise in the repair of fractured porcelain with composite resin at chairside.

Abd Wahab, Mohd Helmy Khalid; Bakar, Wan Zaripah Wan; Husein, Adam

2011-01-01

439

Imide modified epoxy matrix resins  

NASA Technical Reports Server (NTRS)

Results of a program designed to develop tough imide modified epoxy (IME) resins cured by bisimide amine (BIA) hardeners are presented. State of the art epoxy resin, MY720, was used. Three aromatic bisimide amines and one aromatic aliphatic BIA were evaluated. BIA's derived from 6F anhydride (3,3 prime 4,4 prime-(hexafluoro isopropyl idene) bis (phthalic anhydride) and diamines, 3,3 prime-diam nodiphenyl sulfone (3,3 prime-DDS), 4,4 prime-diamino diphenyl sulfone (4,4 prime-DDS), 1.12-dodecane diamine (1,12-DDA) were used. BIA's were abbreviated 6F-3,3 prime-DDS, 6F-4,4 prime-DDS, 6F-3,3 prime-DDS-4,4 prime DDS, and 6F-3,3 prime-DDS-1,12-DDA corresponding to 6F anhydride and diamines mentioned. Epoxy resin and BIA's (MY720/6F-3,3 prime-DDS, MY720/6F-3,3 prime-DDS-4,4 prime-DDS, MY720/6F-3,3 prime-DDS-1,12-DDA and a 50:50 mixture of a BIA and parent diamine, MY720/6F-3,3 prime-DDS/3,3 prime-DDS, MY720/6F-3,3 prime-DDS-4,4 prime-DDS/3,3 prime-DDS, MY720/6F-3,3 prime-DDS-1,12-DDA/3,3 prime-DDS were studied to determine effect of structure and composition. Effect of the addition of two commercial epoxies, glyamine 200 and glyamine 100 on the properties of several formulations was evaluated. Bisimide amine cured epoxies were designated IME's (imide modified epoxy). Physical, thermal and mechanical properties of these resins were determined. Moisture absorption in boiling water exhibited by several of the IME's was considerably lower than the state of the art epoxies (from 3.2% for the control and state of the art to 2.0 wt% moisture absorption). Char yields are increased from 20% for control and state of the art epoxies to 40% for IME resins. Relative toughness characteristics of IME resins were measured by 10 deg off axis tensile tests of Celion 6000/IME composites. Results show that IME's containing 6F-3,3 prime-DDS or 6F-3,3 prime-DDS-1,12-DDA improved the "toughness" characteristics of composites by about 35% (tensile strength), about 35% (intralaminar shear strength), and about 78% (shear strain to failure) relative to the control composite.

Scola, D. A.

1982-01-01

440

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2013 CFR

... false Phenolic resins in molded articles. 177.2410 Section 177.2410...Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified...

2013-04-01

441

40 CFR 721.5908 - Modified phenolic resin (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified phenolic resin (generic). 721.5908 Section 721...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical substance...identified generically as modified phenolic resin (PMN P-01-561) is subject to...

2010-07-01

442

21 CFR 872.3690 - Tooth shade resin material.  

...2014-04-01 2014-04-01 false Tooth shade resin material. 872.3690 Section 872.3690...Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of...

2014-04-01

443

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Resin tooth bonding agent. 872.3200 Section...DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device...

2011-04-01

444

21 CFR 177.2430 - Polyether resins, chlorinated.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Polyether resins, chlorinated. 177.2430 Section 177...for Repeated Use § 177.2430 Polyether resins, chlorinated. Chlorinated polyether resins may be safely used as articles or...

2010-01-01

445

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

... 2014-04-01 false Hydrophilic resin coating for dentures. 872.3300 ...Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device...

2014-04-01

446

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Phenolic resins in molded articles. 177.2410 Section 177...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

2012-04-01

447

21 CFR 872.3310 - Coating material for resin fillings.  

...2014-04-01 false Coating material for resin fillings. 872.3310 Section 872...Devices § 872.3310 Coating material for resin fillings. (a) Identification. A coating material for resin fillings is a device intended to be...

2014-04-01

448

21 CFR 872.3670 - Resin impression tray material.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Resin impression tray material. 872.3670...DEVICES Prosthetic Devices § 872.3670 Resin impression tray material. (a) Identification. Resin impression tray material is a device...

2013-04-01

449

21 CFR 872.3310 - Coating material for resin fillings.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Coating material for resin fillings. 872.3310 Section 872...Devices § 872.3310 Coating material for resin fillings. (a) Identification. A coating material for resin fillings is a device intended to be...

2010-04-01

450

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770 Food...872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2010-04-01

451

40 CFR 721.2673 - Aromatic epoxide resin (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Aromatic epoxide resin (generic). 721.2673 Section 721...Substances § 721.2673 Aromatic epoxide resin (generic). (a) Chemical substance...identified generically as aromatic epoxide resin (PMN P-99-1399) is subject to...

2013-07-01

452

21 CFR 181.32 - Acrylonitrile copolymers and resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Acrylonitrile copolymers and resins. 181.32 Section 181.32 Food and... § 181.32 Acrylonitrile copolymers and resins. (a) Acrylonitrile copolymers and resins listed in this section, containing...

2011-04-01

453

21 CFR 872.3310 - Coating material for resin fillings.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Coating material for resin fillings. 872.3310 Section 872...Devices § 872.3310 Coating material for resin fillings. (a) Identification. A coating material for resin fillings is a device intended to be...

2013-04-01

454

40 CFR 721.2755 - Cycloaliphatic epoxy resin (generic).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Cycloaliphatic epoxy resin (generic). 721.2755 Section 721...Substances § 721.2755 Cycloaliphatic epoxy resin (generic). (a) Chemical substance...identified generically as cycloaliphatic epoxy resin (PMN P-98-105) is subject to...

2011-07-01

455

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Tooth shade resin material. 872.3690 Section 872.3690...Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of...

2011-04-01

456

21 CFR 872.3770 - Temporary crown and bridge resin.  

...2014-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770 Food...872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2014-04-01

457

21 CFR 872.3310 - Coating material for resin fillings.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Coating material for resin fillings. 872.3310 Section 872...Devices § 872.3310 Coating material for resin fillings. (a) Identification. A coating material for resin fillings is a device intended to be...

2012-04-01

458

40 CFR 721.2755 - Cycloaliphatic epoxy resin (generic).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Cycloaliphatic epoxy resin (generic). 721.2755 Section 721...Substances § 721.2755 Cycloaliphatic epoxy resin (generic). (a) Chemical substance...identified generically as cycloaliphatic epoxy resin (PMN P-98-105) is subject to...

2012-07-01

459

21 CFR 173.10 - Modified polyacrylamide resin.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Modified polyacrylamide resin. 173.10 Section 173.10 Food and Drugs...Treatment § 173.10 Modified polyacrylamide resin. Modified polyacrylamide resin may be safely used in food in accordance...

2010-01-01

460

21 CFR 181.32 - Acrylonitrile copolymers and resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Acrylonitrile copolymers and resins. 181.32 Section 181.32 Food and... § 181.32 Acrylonitrile copolymers and resins. (a) Acrylonitrile copolymers and resins listed in this section, containing...

2012-04-01

461

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510 Food and...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles or...

2012-04-01

462

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770 Food...872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2012-04-01

463

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Mineral reinforced nylon resins. 177.2355 Section 177.2355 Food and...Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this...

2012-04-01

464

21 CFR 177.2430 - Polyether resins, chlorinated.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyether resins, chlorinated. 177.2430 Section 177...for Repeated Use § 177.2430 Polyether resins, chlorinated. Chlorinated polyether resins may be safely used as articles or...

2011-04-01

465

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Polyethylene resins, carboxyl modified. 177.1600 Section...Surfaces § 177.1600 Polyethylene resins, carboxyl modified. Carboxyl-modified polyethylene resins may be safely used as the...

2011-04-01

466

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Root canal filling resin. 872.3820 Section 872.3820 Food...Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material,...

2010-04-01

467

21 CFR 872.3670 - Resin impression tray material.  

...2014-04-01 2014-04-01 false Resin impression tray material. 872.3670...DEVICES Prosthetic Devices § 872.3670 Resin impression tray material. (a) Identification. Resin impression tray material is a device...

2014-04-01

468

40 CFR 721.5908 - Modified phenolic resin (generic).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Modified phenolic resin (generic). 721.5908 Section 721...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical substance...identified generically as modified phenolic resin (PMN P-01-561) is subject to...

2011-07-01

469

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Mineral reinforced nylon resins. 177.2355 Section 177.2355 Food and...Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this...

2011-04-01

470

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Polyvinylidene fluoride resins. 177.2510 Section 177.2510 Food and...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles or...

2010-01-01

471

21 CFR 872.3670 - Resin impression tray material.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Resin impression tray material. 872.3670...DEVICES Prosthetic Devices § 872.3670 Resin impression tray material. (a) Identification. Resin impression tray material is a device...

2010-04-01

472

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Epoxy resin containing phosphorus (generic). 721...Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). ...substance identified generically as an epoxy resin containing phosphorus (PMN...

2012-07-01

473

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Resin tooth bonding agent. 872.3200 Section...DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device...

2013-04-01

474

21 CFR 173.10 - Modified polyacrylamide resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Modified polyacrylamide resin. 173.10 Section 173.10 Food and Drugs...Treatment § 173.10 Modified polyacrylamide resin. Modified polyacrylamide resin may be safely used in food in accordance...

2012-04-01

475

21 CFR 872.3820 - Root canal filling resin.  

...2014-04-01 false Root canal filling resin. 872.3820 Section 872.3820 Food...Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material,...

2014-04-01

476

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Resin tooth bonding agent. 872.3200 Section...DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device...

2010-04-01

477