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1

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. 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

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

3

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

4

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

5

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

6

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. 10 figs.

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

1996-07-23

7

Reduction of polyester resin shrinkage by means of epoxy resin—I. Epoxy resin modified with acids  

NASA Astrophysics Data System (ADS)

An attempt was made to decrease the shrinkage of unsaturated polyester resin, taking place during radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified with cinnamic and acrylic acids. A composition of 90 parts of polyesster resin, 10 parts of epoxy resin modified with cinnamic acid, and 150 parts of a silica filler showed a volume shrinkage of 1.2%.

Pietrzak, M.; Brzostowski, A.

8

Antimicrobial activity of resin acid derivatives  

Microsoft Academic Search

The wide potential of resin acids as bioactive agents gave rise to a growing effort in the search for new applications of the natural forms and their derivatives. In some of these compounds, the antimicrobial activity is associated to the presence in the molecules of functional groups such as the hydroxyl, aldehyde, and ketone or to their cis or trans

Sonia Savluchinske-Feio; Maria João Marcelo Curto; Bárbara Gigante; J. Carlos Roseiro

2006-01-01

9

Reactivity of Trametes laccases with fatty and resin acids  

Microsoft Academic Search

Lipophilic extractives commonly referred to as wood pitch or wood resin can have a negative impact on paper machine runnability and product quality. The lipophilic extractives are composed mainly of fatty acids, resin acids, sterols, steryl esters and triglycerides. In this work, the suitability of laccases for the modification of fatty and resin acids was studied, using two model fractions.

Stina Karlsson; Bjarne Holmbom; Peter Spetz; Annikka Mustranta; Johanna Buchert

2001-01-01

10

Antimicrobial activity of resin acid derivatives.  

PubMed

The wide potential of resin acids as bioactive agents gave rise to a growing effort in the search for new applications of the natural forms and their derivatives. In some of these compounds, the antimicrobial activity is associated to the presence in the molecules of functional groups such as the hydroxyl, aldehyde, and ketone or to their cis or trans configurations. The resin acid family covers a spectrum of antimicrobial activities against several microorganisms, from bacteria to fungi, in which the mode of action was studied by electron microscopy. The morphological alterations are consistent with an unspecific mode of action causing inhibition of the fungal growth or damaging the fungal cells in parallel with a mechanism of resistance based on the retention of the compound by the lipid accumulation. The sterol composition of phytopathogenic fungi Botrytis cinerea and Lophodermium seditiosum treated with methyl cis-7-oxo-deisopropyldehydroabietate revealed the presence of ergosterol (M+ 396) and dihydroergosterol (M+ 398) in both cultures showing that this compound did not interfere with the ergosterol metabolic pathway of both fungi. PMID:16896605

Savluchinske-Feio, Sonia; Curto, Maria João Marcelo; Gigante, Bárbara; Roseiro, J Carlos

2006-09-01

11

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

Code of Federal Regulations, 2010 CFR

...true Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2010-04-01

12

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

Code of Federal Regulations, 2012 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2012-04-01

13

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

Code of Federal Regulations, 2014 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2014-04-01

14

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

Code of Federal Regulations, 2013 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2013-04-01

15

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

Code of Federal Regulations, 2011 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2011-04-01

16

Synthesis, characterization and analytical application of a hydroxamic acid resin.  

PubMed

A chelating ion-exchange resin with hydroxamic acid functional groups was synthesized from styrene-maleic acid co-polymer cross-linked with divinylbenzene. A resin prepared from equimolar amounts of styrene and maleic anhydride with 0.75 mole% divinylbenzene gives the best sorption characteristics. The selectivity of the resin for metal ions is copper(II) > cobalt(II) > zinc(II) > nickel(II) > manganese(II) > chromium(III) > iron(III) > vanadium(V). Copper(II), chromium(III) and iron(III) in chromium plating baths can be separated by use of the resin and determined spectrophotometrically. PMID:18964984

Mendez, R; Pillai, V N

1990-06-01

17

Structure—property behaviour of gamma irradiated phosphinic acid resins  

Microsoft Academic Search

The effect of high dose (1000–6000 kGy) gamma radiation on the chemical and physical properties of the ionic polymer phosphinic acid resin has been investigated. It was found that the resin irradiated to a dose of 1000 kGy shows a decrease in the acid capacity of about 8%, reaching 25% at 6000 kGy. In addition, the grain size of the

A. M. El-Naggar; A. S. Emara; S. G. Abd Alla

1997-01-01

18

Synthesis and characterization of hyperbranched and air drying fatty acid based resins  

Microsoft Academic Search

In this research four hyperbranched resins having fatty acid residues were synthesized. Dipentaerythritol, which was used as the core molecule of the resins, was twice esterified with dimethylol propionic acid. This resin was then esterified with the castor oil fatty acids. The hydroxyl group present in the ricinoleic acid which constitutes almost 87% of the castor oil fatty acids was

Erhan Bat; Güngör Gündüz; Duygu K?sakürek; ?dris M. Akhmedov

2006-01-01

19

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

20

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

21

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

22

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

23

Capillary gas chromatography-mass spectrometry of resin acids in tall oil rosin  

Microsoft Academic Search

The resin acid composition of Finnish tall oil rosin was investigated by gas chromatography and mass spectrometry employing\\u000a open tubular capillary columns. On a column coated with 1,4-butanediol succinate, 16 resin acids found in tall oil rosin samples\\u000a were well resolved, and mass spectra could be recorded. All resin acids were confirmed to be of the pimaric and abietic types

B. Holmbom; E. Avela; S. Pekkala

1974-01-01

24

Fatty acid-based monomers as styrene replacements for liquid molding resins  

Microsoft Academic Search

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 inexpensive, have low volatilities, and free-radically polymerize with vinyl ester. The viscosity of VE resins using these fatty acid monomers ranged

John J. La Scala; James M. Sands; Joshua A. Orlicki; E. Jason Robinette; Giuseppe R. Palmese

2004-01-01

25

(Invited Review Paper) Preparation, Properties and Sorption Behavior of Impregnated Resins Containing Acidic Organophosphorus Extractants  

Microsoft Academic Search

In this paper, the preparation methods and physical properties of solvent-impregnated resin (SIR) containing acidic organophosphorus extractants are reviewed. The sorption phenomena of these resins, including batch equilibrium, kinetics, and column operation, are also described. The widely-used extractant di(2-ethylhexyl)phosphoric acid and Amberlite XAD macroporous resins for the recovery and selective separation of Cu(II) and Zn(II) ions is studied. In addition,

RUEY-SHIN JUANG

26

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

27

UPTAKE OF GOLD FROM HYDROCHLORIC ACID SOLUTIONS BY POLYMERIC RESINS BEARING VARIOUS PHOSPHORUS CONTAINING LIGANDS  

Microsoft Academic Search

Polymeric resins with phosphonate esters, phosphinate esters, and phosphine oxide ligands are synthesized via Arbusov reaction, characterized and used in the removal of Au(III) from hydrochloric acid solutions. It is found that phosphonate ethyl and butyl esters are able to adsorb as much as 100–120 mg Au\\/g of the resin. Affinity of these two resins towards gold, measured as the logarithm

Andrzej W. Trochimczuk

2002-01-01

28

SELECTIVE RECOVERY OF GOLD FROM ACIDIC SOLUTIONS USING RESINS WITH METHYLENEDIPHOSPHONATE AND CARBOXYMETHYLPHOSPHONATE LIGANDS  

Microsoft Academic Search

The polymeric resins with methylenediphosphonate and carboxymethylphosphonate ligands in the ethyl ester form have been synthesized, characterized and used in the removal of Au(III) from hydrochloric acid solutions. It has been found that they are able to adsorb as much as 130–166 mg Au\\/g of the resin at high concentration of the external solutions. At low concentrations affinity of resins

Andrzej W. Trochimczuk

2001-01-01

29

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

30

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

31

Quantitative composition of the resin acids produced by the coniferous species of the USSR  

Microsoft Academic Search

Conclusions  1. The chemical composition of mixtures of resin acids isolated from the balsams of native conifer species, Scotch, Crimean,\\u000a and Siberian pines andP. hamota andP. pityusa, Norway spruce, and Siberian larch, has been studied by the GLC method.\\u000a \\u000a 2. The following resin acids are present in the balsams: pimaric, sandaracopimaric, levopimaric, palustric, isopimaric, abietic,\\u000a dehydro- and dihydroabietic, neoabietic, four acids

I. I. Bardyshev; A. N. Bulgakov; A. L. Pertsovskii

1970-01-01

32

Microbial activity in an acid resin deposit: biodegradation potential and ecotoxicology in an extremely acidic hydrocarbon contamination.  

PubMed

Acid resins are residues produced in a recycling process for used oils that was in use in the forties and fifties of the last century. The resin-like material is highly contaminated with mineral oil hydrocarbons, extremely acidic and co-contaminated with substituted and aromatic hydrocarbons, and heavy metals. To determine the potential for microbial biodegradation the acid resin deposit and its surroundings were screened for microbial activity by soil respiration measurements. No microbial activity was found in the core deposit. However, biodegradation of hydrocarbons was possible in zones with a lower degree of contamination surrounding the deposit. An extreme acidophilic microbial community was detected close to the core deposit. With a simple ecotoxicological approach it could be shown that the pure acid resin that formed the major part of the core deposit, was toxic to the indigenous microflora due to its extremely low pH of 0-1. PMID:16530313

Kloos, Karin; Schloter, Michael; Meyer, Ortwin

2006-11-01

33

Resin–dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding  

PubMed Central

Objective To compare resin–dentin bond strengths and the micropermeability of hydrophobic vs. hydrophilic resins bonded to acid-etched or EDTA-treated dentin, using the ethanol wet-bonding technique. Methods Flat dentin surfaces from extracted human third molars were conditioned before bonding with: 37% H3PO4 (15 s) or 0.1 M EDTA (60 s). Five experimental resin blends of different hydrophilicities and one commercial adhesive (SBMP: Scotchbond Multi-Purpose) were applied to ethanol wet-dentin (1 min) and light-cured (20 s). The solvated resins were used as primers (50% ethanol/50% comonomers) and their respective neat resins were used as the adhesive. The resin-bonded teeth were stored in distilled water (24 h) and sectioned in beams for microtensile bond strength testing. Modes of failure were examined by stereoscopic light microscopy and SEM. Confocal tandem scanning microscopy (TSM) interfacial characterization and micropermeability were also performed after filling the pulp chamber with 1 wt% aqueous rhodamine-B. Results The most hydrophobic resin 1 gave the lowest bond strength values to acid-etched dentin and all beams failed prematurely when the resin was applied to EDTA-treated dentin. Resins 2 and 3 gave intermediate bond strengths to both conditioned substrates. Resin 4, an acidic hydrophilic resin, gave the highest bond strengths to both EDTA-treated and acid-etched dentin. Resin 5 was the only hydrophilic resin showing poor resin infiltration when applied on acid-etched dentin. Significance The ethanol wet-bonding technique may improve the infiltration of most of the adhesives used in this study into dentin, especially when applied to EDTA-treated dentin. The chemical composition of the resin blends was a determining factor influencing the ability of adhesives to bond to EDTA-treated or 37% H3PO4 acid-etched dentin, when using the ethanol wet-bonding technique in a clinically relevant time period. PMID:20074787

Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H.; Tay, Franklin R.; Watson, Timothy F.; Osorio, Raquel

2013-01-01

34

Isolation of hydrophilic organic acids from water using nonionic macroporous resins  

USGS Publications Warehouse

A method has been developed for the isolation of hydrophilic organic acids from aquatic environments using Amberlite* * Use of trade names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. XAD-4 resin. The method uses a two column array of XAD-8 and XAD-4 resins in series. The hydrophobic organic acids, composed primarily of aquatic fulvic acid, are removed from the sample on XAD-8, followed by the isolation of the more hydrophilic organic acids on XAD-4. For samples from a number of diverse environments, more of the dissolved organic carbon was isolated on the XAD-8 resin (23-58%) than on the XAD-4 resin (7-25%). For these samples, the hydrophilic acids have lower carbon and hydrogen contents, higher oxygen and nitrogen contents, and are lower in molecular weight than the corresponding fulvic acids. 13C NMR analyses indicate that the hydrophilic acids have a lower concentration of aromatic carbon and greater heteroaliphatic, ketone and carboxyl content than the fulvic acid. ?? 1992.

Aiken, G.R.; McKnight, D.M.; Thorn, K.A.; Thurman, E.M.

1992-01-01

35

Large scale purification of puerarin from Puerariae Lobatae Radix through resins adsorption and acid hydrolysis.  

PubMed

Puerarin is the major isoflavone of Puerariae Lobatae Radix. A method for large scale purification of puerarin was developed through resins adsorption and acid hydrolysis. The adsorption properties of six macroporous resins (D101, S-8, H103, X-5, HPD600, AB-8) were compared through the adsorption kinetics and equilibrium adsorption isotherms. Results showed that H103 resin had the best adsorption rate and capacity. The mass transfer zone motion model was further used for analyzing the fixed bed adsorption of H103 resin. Its length of mass transfer zone with 2mg/ml of puerarin in water and 10% ethanol at flow rate of 10ml/min were 41.6 and 47.5cm, while the equilibrium adsorption capacity was 165.03 and 102.88mg/g, respectively. By using 75% ethanol, puerarin could be well desorbed from the resin with recovery of 97.4%. Subsequently, H103 resin was successfully used for puerarin purification from Puerariae Lobatae Radix. The content of total isoflavones and puerarin in the resin adsorption product were 69.25% and 41.78%, respectively, which were about three times increased compared to the crude extract. Then, the product was hydrolyzed by 2.5M HCl at 90°C for 1h. Puerarin with purity of 90% and a byproduct daidzein with purity of 78% were obtained. PMID:25553536

Guo, Hai-Dong; Zhang, Qing-Feng; Chen, Ji-Guang; Shangguang, Xin-Cheng; Guo, Yu-Xian

2015-02-01

36

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. PMID:7887603

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

1995-01-01

37

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

38

Synthesis, characterization and applications of a new cation exchanger tamarind sulphonic acid (TSA) resin.  

PubMed

A new composite cation exchanger, tamarind sulphonic acid (TSA) resin has been synthesized. The chemically modified TSA ion exchange resin has been used for the removal and preconcentration of Zn2+, Cd2+, Fe2+, Co2+ and Cu2+ ions in aqueous solution and effluent from the Laxmi steel plant in Jodhpur, India. This type of composite represents a new class of hybrid ion exchangers with good ion exchange capacity, stability, reproducibility and selectivity for toxic metal ions found in effluent from the steel industry. The characterization of the resin was carried out by determining the ion-exchange capacity, elemental analysis, pH titration, Fourier transform infrared spectra and thermal analysis. The distribution coefficients (K(d)) of toxic metal ions were determined in a reference aqueous solution and the steel plant effluent at different pH values; the absorbency of different metal ions on the TSA resin was studied for up to 10 cycles. The adsorption of different metal ions on TSA resin follows the order: Co2+ > Cu2+ > Zn2+ > Fe2+ > Cd2+. The ion exchange capacity of TSA resin is 2.87%. PMID:22629619

Singh, A V; Sharma, Naresh Kumar; Rathore, Abhay S

2012-01-01

39

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

40

Northwood Pulp Mill -Winter 1996 Resin Acids and 1994-1996 Chlorophenolic Compounds Summary Report  

E-print Network

;Any comments regarding this report should be forwarded to: Technology and Pollution Prevention Section variability existed among eight participating laboratories. In 1996, AXYS Analytical (AXYS), Pacific Environmental Science Centre (PESC) and Institute of Ocean Sciences (IOS) analyzed resin acids in each of ten 24

41

Kinetics of Ethyl Acetate Synthesis Catalyzed by Acidic Resins  

ERIC Educational Resources Information Center

A low-cost experiment to carry out the second-order reversible reaction of acetic acid esterification with ethanol to produce ethyl acetate is presented to illustrate concepts of kinetics and reactor modeling. The reaction is performed in a batch reactor, and the acetic acid concentration is measured by acid-base titration versus time. The…

Antunes, Bruno M.; Cardoso, Simao P.; Silva, Carlos M.; Portugal, Ines

2011-01-01

42

Resin Bead Detection and Spectrophotometric Determination of Ascorbic Acid in Pharmaceutical Preparations Using m-Dinitrobenzene  

Microsoft Academic Search

A colorimetric reaction has been studied for the detection and determination of ascorbic acid in samples at the microgram level. the method is simple, rapid, and sensitive, the ascorbic acid was detected using resin beads and determined spectrophotometrically using m-dinitrobenzene in formaldehyde. the detection limit was 10?g. Beer's law is obeyed in the concentration range of 2 – 50?g\\/ml of

Saidul Zafar Qureshi; Ahsan Saeed; Tausiful Hasan

1989-01-01

43

Selection of resins, equilibrium and sorption kinetics of lactobionic acid, fructose, lactose and sorbitol  

Microsoft Academic Search

The separation of quaternary mixtures of lactobionic acid, lactose, sorbitol and fructose using a gel-type ion-exchange resin loaded with H+, K+ and Ca2+ ions has been investigated. This separation is relevant in order to improve the productivity of lactobionic acid obtained from the enzymatic reaction catalyzed by Glucose–fructose oxidoreductase and glucono-?-lactonase enzymes. Measurement of the single-component equilibrium isotherms for all

I. Pedruzzi; E. A. Borges da Silva; A. E. Rodrigues

2008-01-01

44

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

45

Preconcentration and speciation of chromium using a melamine based polymeric sequestering succinic acid resin: its application for Cr(VI) and Cr(III) determination in wastewater  

Microsoft Academic Search

A new melamine based polymeric sequestering resin was prepared for preconcentration and separation of hexavalent chromium from water, and its sequestering action was investigated. The water-insoluble, cross-linked sequestering resin was formed by reaction with bromosuccinic acid and cross-linking of melamine. The active sequestering group on the resin is ?NH–(Succinic acid) or salt thereof. The resulting chelating resin was characterized by

Melek Do?utan; Hayati Filik; ?zzet Tor

2003-01-01

46

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

47

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

SciTech Connect

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 the Hanford site. The elution step of the multi-step ion exchange process is typically done with 0.5 M nitric acid. An acid eluant is a potential hazard in the event of a spill, leak, etc. because the high-level waste tanks are made of carbon steel. Corrosion and associated structural damage may ensue. A study has been conducted to explore non-acid elution as an alternative. Batch contact sorption equilibrium screening tests have been conducted with 36 potential non-acid eluants. The sorption tests involve equilibrating each cesium-containing eluant solution with the sRF resin for 48 hours at 25 C in a shaker oven. In the sorption tests, an eluant is deemed to have a high cesium elution potential if it minimizes cesium sorption onto the sRF resin. The top candidates (based on lowest cesium sorption distribution coefficients) include ammonium carbonate, ammonium carbonate/ammonium hydroxide, ammonium bicarbonate, rubidium carbonate, ammonium acetate, ammonium acetate/ammonium hydroxide, ammonium bicarbonate/ammonium hydroxide, calcium chloride, and magnesium chloride. A select few of the top candidate eluants from the screening tests were subjected to actual sorption (loading) and elution tests to confirm their elution ability. The actual sorption (loading) and elution tests mimicked the typical sRF-cesium ion exchange process (i.e., sorption or loading, caustic wash, water rinse, and elution) via batch contact sorption and quasi column caustic wash/water rinse/elution. The eluants tested included ammonium carbonate, ammonium acetate, calcium acetate, magnesium acetate, and nitric acid. Calcium acetate and magnesium acetate were substitutes for calcium chloride and magnesium chloride respectively due to corrosion concerns. Nitric acid was selected for benchmarking since it is the baseline cesium eluant for sRF resin. The cesium elution performance of ammonium carbonate and ammonium acetate was approximately the same as the benchmark eluant, nitric acid. Ninety-seven (97), 94, and 100% percent of the cesium sorbed or loaded were eluted by ammonium carbonate, ammonium acetate, and nitric acid was respectively. The performance of calcium acetate and magnesium acetate, on the other hand, was mediocre. Percent elution was 16 and 8 respectively.

Adu-Wusu, K.; Pennebaker, F.

2010-12-22

48

Synthesis, characterization and adsorption properties of diethylenetriamine-modified hypercrosslinked resins for efficient removal of salicylic acid from aqueous solution.  

PubMed

We report an effective approach for tailoring the pore textural properties and surface polarity of a hypercrosslinked resin to enhance its adsorption capacity and selectivity for removing salicylic acid from aqueous solution. Four hypercrosslinked resins were synthesized by controlling the reaction time of the self Friedel-Crafts reaction of chloromethylated polystyrene-co-divinylbenzene, and then modified with diethylenetriamine to adjust their surface polarity. The resins were characterized with N(2) adsorption for pore textural properties, Fourier transform infrared spectroscopy (FT-IR) for surface functional groups, chemical analysis for residual chlorine content and weak basic exchange capacity. Adsorption equilibrium, kinetics and breakthrough performance were determined for the removal of salicylic acid from aqueous solution on a selected resin HJ-M01. The equilibrium adsorption capacity of salicylic acid on HJ-M01 is significantly higher than that on its precursor HJ-11 and a few commercial adsorbents including AB-8, XAD-4 and XAD-7. The dynamic adsorption capacity of salicylic acid on HJ-M01 was found to be 456.4 mg/L at a feed concentration of 1000 mg/L and 294 K. The used resin could be fully regenerated with 1% sodium hydroxide solution. The hypercrosslinked resins being developed were promising alternatives to commercial adsorbents for removing salicylic acid and other volatile organic compounds (VOCs) from aqueous solution. PMID:22482881

Huang, Jianhan; Jin, Xiaoying; Mao, Jinglin; Yuan, Bin; Deng, Rujie; Deng, Shuguang

2012-05-30

49

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. PMID:23755333

Motro, Pelin Fatma Karagoz; Yurdaguven, Haktan

2013-01-01

50

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

Code of Federal Regulations, 2014 CFR

...Product groups are indicated with an asterisk (*). *Alkyd Resins Dicyanodiamide Resin *Epoxy Resins *Fumaric Acid Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins...

2014-07-01

51

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

Code of Federal Regulations, 2013 CFR

...Product groups are indicated with an asterisk (*). *Alkyd Resins Dicyanodiamide Resin *Epoxy Resins *Fumaric Acid Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins...

2013-07-01

52

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

53

Application of electrolyzed acid water to sterilization of denture base part 1. Examination of sterilization effects on resin plate.  

PubMed

Bactericidal activities of electrolyzed strong and weak acid waters for acrylic denture base resin were evaluated in order to discuss the applicability of these waters for sterilization of denture base. Only 1-minute immersion in the electrolyzed strong or weak acid water could completely eliminate the attached bacteria, Staphylococcus aureus 209P, on the resin plate. When the resin was relined with tissue conditioner, 5-minute immersion or 1- to 2-minute ultrasonic cleaning reduced the number of the bacteria from 10(5)/cm2 level to 10(1)/cm2 and no surviving bacteria could be detected after 10-minute treatment. These findings suggest that both the electrolyzed strong and weak acid waters are well applicable to the disinfectant for acrylic denture base showing excellent bactericidal activities in a significantly shorter treatment as compared with the conventional denture cleaning. PMID:11523978

Nagamatsu, Y; Tajima, K; Kakigawa, H; Kozono, Y

2001-06-01

54

Radiolytic and chemical degradation of strong acidic ion-exchange resins: Study of ligands formed  

SciTech Connect

The formation of water-soluble organic ligands by radiolytic and chemical degradation of several strong acidic ion-exchange resins was investigated under conditions close to those of the near field of a cementitious repository. The most important degradation products were studied and their complexing properties evaluated. Irradiation of strong acidic cation exchange resins (Powder PCH and Lewatite S-100) resulted in the formation of mainly sulfate and dissolved organic carbon. High-performance liquid chromatography analysis indicated the presence of oxalate, contributing to 10 to 20% of the organic carbon. The identity of the remainder is unknown. The presence of oxalate as a complexant is consistent with results from earlier work. Complexation studies with Cu{sup 2+} and Ni{sup 2+} showed the presence of two ligands: oxalate and ligand X. Although ligand X could not be identified, it could be characterized by its concentration ([X]{sub T} {approximately} 10{sup {minus}5} to 10{sup {minus}6} M), a deprotonation constant (pK{sub H} {approximately} 7.4 at I = 0.1 M), and a complexation constant for the NiX complex (log K{sub NiX}{approximately} 7.0 at I = 0.1 M). In the absence of irradiation, no evidence for the formation of ligands was found.

Loon, L.R. van; Hummel, W.

1999-12-01

55

Surface roughness of flowable resin composites eroded by acidic and alcoholic drinks  

PubMed Central

Aim: The aim of this study is to evaluate the surface roughness of four flowable resin composites following exposure to acidic and alcoholic drinks. Materials and Methods: SureFil SDR flow, TetricEvoFlow, Esthet-X Flow and Amaris Flow HT samples were immersed in artificial saliva, Coca Cola and Chivas Regal Whisky. Each specimen was examined using a Leica DCM 3D microscope: Arithmetical mean height of the surface profiles was measured (Sa). Results: Kruskal-Wallis test showed significant differences among various groups (P<0,001). Mann Whitney test was applied and control groups showed significantly lower Sa values than other groups (P=0,008). Coca Cola groups showed highest Sa values (P<0,021). No significant differences (P=0,14) in surface texture were found among the specimens of the different materials. No significant differences were found among TetricEvoFlow, Esthet-X Flow and Amaris Flow under control conditions nor after Coca Cola application. Under control condition and after Coca Cola application SureFil SDR flow showed significantly higher Sa values. Moreover, after whisky application Amaris Flow showed significantly lower Sa values then the other three groups that showed no significant differences among them. Conclusions: Acidic and alcoholic drinks eroded the surface roughness of all evaluated flowable resin composites. PMID:22557811

Poggio, Claudio; Dagna, Alberto; Chiesa, Marco; Colombo, Marco; Scribante, Andrea

2012-01-01

56

Identification of dehydroabietc acid from Boswellia thurifera resin as a positive GABAA receptor modulator.  

PubMed

In a two-microelectrode voltage clamp assay with Xenopus laevis oocytes, a petroleum ether extract (100 ?g/mL) of the resin of Boswellia thurifera (Burseraceae) potentiated GABA-induced chloride currents (IGABA) through receptors of the subtype ??????s by 319.8% ± 79.8%. With the aid of HPLC-based activity profiling, three known terpenoids, dehydroabietic acid (1), incensole (2), and AKBA (3), were identified in the active fractions of the extract. Structure elucidation was achieved by means of HR-MS and microprobe 1D/2D NMR spectroscopy. Compound 1 induced significant receptor modulation in the oocyte assay, with a maximal potentiation of IGABA of 397.5% ± 34.0%, and EC?? of 8.7 ?M ± 1.3 ?M. This is the first report of dehydroabietic acid as a positive GABAA receptor modulator. PMID:25200370

Rueda, Diana C; Raith, Melanie; De Mieri, Maria; Schöffmann, Angela; Hering, Steffen; Hamburger, Matthias

2014-12-01

57

Isolation and characterization of resin acid degrading bacteria found in effluent from a bleached kraft pulp mill.  

PubMed

Thirteen resin acid degrading bacteria enriched on abietic or dehydroabietic acids were isolated from waste water from the aerated stabilization basin of a bleached kraft pulp mill. Standard biochemical tests were used to characterize each isolate. Each isolate was tested for its ability to degrade six abietane- and pimarane-type resin acids. Resin acid concentrations were determined by high pressure liquid chromatography and UV absorbance. Cluster analysis based on phenotypic characteristics identified two distinct clusters of degraders that differed in their ability to utilize carbohydrates as carbon sources. Fatty acid methyl ester analysis of representative isolates from each cluster identified A19-6a and D11-13 as Comamonas and Alcaligenes species, respectively. To determine genotypic relatedness, enterobacterial repetitive intergenic consensus sequences were used to amplify genomic DNA fragments from 10 isolates. These results supported the phenotypic analysis for all isolates tested except A19-5 and A19-6b. These two organisms were clustered closely together based on phenotype but had distinctly different banding patterns, suggesting that they are not related genotypically. All isolates degraded a subset of the six resin acid congeners. Isolates A19-3, A19-6a, A19-6b, and D11-37 were the most effective at degrading all six congeners. PMID:8640603

Morgan, C A; Wyndham, R C

1996-05-01

58

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

59

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

60

Low pressure process for continuous fiber reinforced polyamic acid resin matrix composite laminates  

NASA Technical Reports Server (NTRS)

A low pressure processor was developed for preparing a well-consolidated polyimide composite laminate. Prepreg plies were formed from unidirectional fibers and a polyamic acid resin solution. Molding stops were placed at the sides of a matched metal die mold. The prepreg plies were cut shorter than the length of the mold in the in-plane lateral direction and were stacked between the molding stops to a height which was higher than the molding stops. The plies were then compressed to the height of the stops and heated to allow the volatiles to escape and to start the imidization reaction. After removing the stops from the mold, the heat was increased and 0 - 500 psi was applied to complete the imidization reaction. The heat and pressure were further increased to form a consolidated polyimide composite laminate.

Druyun, Darleen A. (inventor); Hou, Tan-Hung (inventor); Kidder, Paul W. (inventor); Reddy, Rakasi M. (inventor); Baucom, Robert M. (inventor)

1994-01-01

61

Fixed bed adsorption of 2-naphthalenesulfonic acid from aqueous solution by composite resin.  

PubMed

Adsorption behavior of the iron impregnated, weakly basic resin D301 (Fe-D301) for removal of 2-naphthalenesulfonic acid (2-NSA) from aqueous solution was studied by using a fixed-bed column. The effects of process variables such as bed height, flow rate, and coexisting ions were investigated. The results indicated that the breakpoint and exhaustion point increased with increasing bed height and decreased with increasing 2-NSA flowrate. Experimental data showed a strong fit to the Bed Depth Service Time model. The coexisting ions in the 2-NSA solution had a clear effect on the breakthrough volume. The high extent of recovery of 2-NSA with good reproducibility provided an effective method for the separation of 2-NSA by the adsorbent Fe-D301. PMID:24645539

Jia, Dong M; Li, Ya P; Li, Yue J; Li, Yong G; Li, Chang H

2014-02-01

62

Coadsorption of trivalent metal ions and anions on strongly acidic cation-exchange resins by bridge bonding.  

PubMed

The effects of anions (P(V), P(III), P(I), Se(IV), OH(-), F(-), Cl(-), SCN(-), S(IV), and CH(3)COO(-)) on the adsorption of trivalent metal ions (Fe(3+), Al(3+), Ga(3+), In(3+), and Sc(3+)) to three strongly acidic cation-exchange resins (-S)(-) of different types (porous or gel) and different exchange capacities (4.55, 3.91, and 0.96 mmol g(-1)) were studied systematically. All these metal ions showed coadsorption of OH(-), irrespective of the resins. In contrast, coadsorption of P(V), P(III), P(I), and Se(IV) was observed on the resins of the higher exchange capacities but not on the resin of the lowest exchange capacity. Stoichiometric analyses and spectroscopic (Mossbauer and infrared) studies for Fe(3+) demonstrated the presence of the coadsorbed species: [(-S)(2)Fe(OH)] and [(-S)(2)(Fe-O-Fe)(S-)(2)] for OH(-), [(-S)(2)Fe(HPO(4))Fe(S-)(2)] for P(V), and [(-S)(2)FeX](j) (X(-) = H(2)PO(3)(-), H(2)PO(2)(-), HSeO(3)(-); j > 1) for P(III), P(I), and Se(IV). No coadsorption was observed for the other anions. These findings indicate that the bridge bonding of anions between the metal ions adsorbed on the resins of the higher exchange capacities plays a crucial role for the coadsorption. Some analytical implication was also discussed. PMID:19072270

Matsuura, Takanori; Ohnaka, Kenji; Takagi, Mayuu; Ohashi, Miki; Mibu, Ko; Yuchi, Akio

2008-12-15

63

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

64

Novel bioactive polyester scaffolds prepared from unsaturated resins based on isosorbide and succinic acid.  

PubMed

In this study new biodegradable materials obtained by crosslinking poly(3-allyloxy-1,2-propylene succinate) (PSAGE) with oligo(isosorbide maleate) (OMIS) and small amount of methyl methacrylate were investigated. The porous scaffolds were obtained in the presence of a foaming system consisted of calcium carbonate/carboxylic acid mixture, creating in situ porous structure during crosslinking of liquid formulations. The maximum crosslinking temperature and setting time, the cured porous materials morphology as well as the effect of their porosity on mechanical properties and hydrolytic degradation process were evaluated. It was found that the kind of carboxylic acid used in the foaming system influenced compressive strength and compressive modulus of porous scaffolds. The MTS cytotoxicity assay was carried out for OMIS using hFOB1.19 cell line. OMIS resin was found to be non-toxic in wide range of concentrations. On the ground of scanning electron microscopy (SEM) observations and energy X-ray dispersive analysis (EDX) it was found that hydroxyapatite (HA) formation at the scaffolds surfaces within short period of soaking in phosphate buffer solution occurs. After 3h immersion a compact layer of HA was observed at the surface of the samples. The obtained results suggest potential applicability of resulted new porous crosslinked polymeric materials as temporary bone void fillers. PMID:25491802

Smiga-Matuszowicz, Monika; Janicki, Bartosz; Jaszcz, Katarzyna; ?ukaszczyk, Jan; Kaczmarek, Marcin; Lesiak, Marta; Siero?, Aleksander L; Simka, Wojciech; Mierzwi?ski, Maciej; Kusz, Damian

2014-12-01

65

Comparative evaluation of retentive properties of acid etched resin bonded fixed partial dentures  

PubMed Central

Background Little consensus exist in suitable tooth preparation design and alloy pre-treatment methods for improving the retention of resin bonded fixed partial dentures (RBFPDs). Methods An in-vitro experiment was done with four designs. Group A: standard form, B: wings and proximal slices, C: wings, proximal slice and grooves, D: wings, proximal slice, grooves and occlusal coverage. Alloys were subjected to pre-treatment procedures like Group I: control, II: sand blasting, III: electro etching, IV: tin plating. Debonding forces of the castings were recorded in a universal testing machine and results were analyzed by student's ‘t’ test. Results Group B, C and D showed higher debonding forces compared to A. However, there were no significant differences in mean force values among Groups B, C and D. Group II, III and IV with different alloy pre-treatment methods demonstrated higher values against control. Inter group variations among Group II, III and IV were not significant. Conclusion Tooth preparation with adequate surface extensions and pre-treatment procedures of casting alloys are two parameters that play important role in determining the retentive features of RBFPDs. Different types of tooth preparation designs and alloy pre-treatment methods exert almost similar influence in increasing the retention of acid etched RBFPDs. PMID:24623948

Arora, Vimal; Sharma, M.C.; Dwivedi, Ravi

2013-01-01

66

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 20 FPU/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

67

Relative sensitivity of five benthic invertebrate species to reference toxicants and resin-acid contaminated sediments  

SciTech Connect

Five sediment-dwelling native New Zealand freshwater invertebrate species (amphipod, Chaetocorophium c.f. lucasi; clam, Sphaerium novaezelandiae; oligochaete, Lumbriculus variegatus; tanaid, Tanais standfordi; and the burrowing mayfly, Ichthybotus hudsoni) were assessed for their suitability for sediment toxicity testing by comparison of sensitivity to reference toxicants [phenol and pentachlorophenol (PCP)] and contaminated sediments. The 96-h EC50 values at 20 C showed a greater range in test sensitivity for phenol (30-fold range) from the most sensitive test, amphipod (8.1 mg/L), to the least sensitive one, clam (243 mg/L), compared with PCP (14-fold range), with amphipod the most sensitive test species (0.13 mg/L) and tanaid the least sensitive (1.8 mg/L). Clam reburial was a more sensitive end point than was lethality for phenol (by 20-fold) and PCP (by 2.4-fold). Four of the test species, excluding the tanaid, showed good 10-d survival in reference muds ({ge}87%) but lower survival in sand sediments ({ge}79%). Bleached kraft mill sediment containing high resin-acid concentrations (total 1,900 mg/kg dry weight) showed significant reductions in amphipod survival (15%), clam reburial (30%), and oligochaete survival (17%), and reproduction (49%). Amphipods, clams, and oligochaetes were the most promising species for sublethal test development.

Hickey, C.W.; Martin, M.L. [National Inst. of Water and Atmospheric Research, Hamilton (New Zealand). NIWA Ecosystems

1995-08-01

68

Preparative separation of lithospermic acid B from Salvia miltiorrhiza by polyamide resin and preparative high-performance liquid chromatography.  

PubMed

Adsorption on polyamide resin was investigated as a means of separating lithospermic acid B (LAB) from a crude extract of the roots of the traditional Chinese medicine Salvia miltiorrhiza Bunge ("Danshen"). Variables affecting adsorption capacity (solution pH, contact time on resin, initial LAB concentration) were studied. Adsorption was strongly dependent upon the initial concentration of LAB and pH. In all conditions, the polyamide resin gave optimal adsorption of LAB at an initial concentration of 2.66 mg/mL and pH <3.0. The adsorption isotherm correlated well with the Langmuir-type adsorption isotherm. Maximal adsorption capacity was calculated to be 380 mg/g at pH 2.0 and 25°C. LAB purity of 85.30% could be obtained by polyamide resin adsorption followed by elution with 70% ethanol solution, and the recovery was 87.1%. After preparative HPLC, the maximum HPLC purity obtained was 99.28% with a recovery of 75.2%. This method provides an efficient and low-cost method for LAB purification for industrial applications. PMID:21652037

Guo, Y X; Zhou, L L; Li, T; Wang, L H

2011-07-22

69

Novel polysiloxane resin functionalized with dicyclohexano-18-crown-6 (DCH18C6): Synthesis, characterization and extraction of Sr(II) in high acidity HNO3 medium.  

PubMed

A novel kind of polysiloxane resin functionalized with dicyclohexano-18-crown-6 (DCH18C6) was synthesized through a post-modification approach. The DCH18C6 moieties bearing amino groups were firstly prepared, followed by covalent grafting to a silica precursor P-(CH(2))(3)-Cl (Where P represents a 3-dimentional polymerized silica matrix) based on nucleophilic substitution reaction. (29)Si and (13)C solid-state NMR, FT-IR, XPS, TGA, ESEM and elemental analysis were employed to systematically characterize the structure, thermal property and surface morphology of the functionalized resin. The results indicated that the DCH18C6 ligands were successfully bonded to the polysiloxane resin with a satisfactory grafting degree (33.6wt.%). Due to the robust organosilica framework and the covalent immobilization of the ligands, the functionalized resin had excellent thermal stability and acid resistance. Batch experiments showed that the resin could effectively separate Sr(II) in high acidity mediums. The distribution coefficient (K(d)) of 43.6cm(3)/g could be achieved in 5.0mol/L HNO(3) solution. The influences of contact time and acidity of HNO(3) on the resin's extraction performance were examined. The reusability and the selectivity to Sr(II) over interference ions were investigated. The DCH18C6-functionalized resin might be potentially applied for the radiostrontium removal in the high level liquid waste (HLLW). PMID:22609393

Ye, Gang; Bai, Feifei; Wei, Jichao; Wang, Jianchen; Chen, Jing

2012-07-30

70

Metal binding characterization and conformational studies using Raman microscopy of resin-bound poly(aspartic acid).  

PubMed

The metal binding capacities, conditional stability constants, and secondary structure of immobilized polyaspartic acid (PLAsp) (n = 6, 20, and 30) on TentaGel resin were determined when binding Mg2+, Co2+, Cd2+, and Ni2+. Metal binding to the synthesized peptides was evaluated using breakthrough curves from a packed microcolumn and flame atomic absorption spectrophotometry (FAAS) detection. The metal capacities reached values of 590, 2160, and 3710 mumol of metal/g of resin for the 6-mer, 20-mer, and 30-mer, respectively, and this resulted in 2-3 residues per metal for all peptides and metals tested. Surprisingly, the concentrated environment of the resin along with the spatial distribution of attachment groups allowed for most residues to participate in metal binding regardless of the peptide length. Conditional stability constants calculated using single metal binding isotherms indicated that binding strength decreased as the chain length increased on the resin. Raman microscopy on single beads was used to determine PLAsp secondary structure, and all peptides were of a mixed conformation (i.e., beta-sheets, alpha-helices, random chain, etc.) during neutral conditioning and metal binding. Uniquely, the longer 20-mer and 30-mer peptides showed a distinct change from a mixed conformation to beta-sheets and alpha-helices during metal release with acid. This study confirms that metal release by longer immobilized peptides is often assisted by a conformational change, which easily spoils the binding cavity, while shorter peptides may release metal primarily by H+ displacement. PMID:17249637

Stair, Jacqueline L; Holcombe, James A

2007-03-01

71

Selected resin acids in effluent and receiving waters derived from a bleached and unbleached kraft pulp and paper mill  

USGS Publications Warehouse

Water samples were collected on three dates at 24 sites influenced by effluent from Georgia-Pacific's Palatka Pulp and Paper Mill Operation, a bleached and unbleached kraft mill near Palatka, Florida, USA. The sampling sites were located within the mill retention ponds, Rice Creek, and the St. John's River. Samples were analyzed by gas chromatography-mass spectrometry for abietic, dehydroabietic, and isopimaric acids, all of which are potentially toxic by-products of pulp production. Isopimaric acid concentrations greater than 12 mg/L were measured at the mill's effluent outfall but were less than 20 ??g/L at the end of Rice Creek. This result indicates that the waters of Rice Creek provide dilution or conditions conducive for degradation or sorption of these compounds. Large differences in resin acid concentrations were observed between sampling events. In two sampling events, the maximum observed concentrations were less than 2 mg/L for each analyte. In a third sampling event, all of the compounds were detected at concentrations greater than 10 mg/L. Data from the three sample dates showed that resin acid concentrations were below 20 ??g/L before the confluence of Rice Creek and the St. John's River in all cases.

Quinn, B.P.; Booth, M.M.; Delfino, J.J.; Holm, S.E.; Gross, T.S.

2003-01-01

72

Small-Angle X-ray Scattering Study on Covalently Cross-linked Polyvinyl Alcohol\\/Epoxy Resin Membrane in Polyphosphoric Acid  

Microsoft Academic Search

Covalently cross-linked polyvinyl alcohol\\/epoxy resin membranes were prepared with different ratios of epoxy resin and cross-linking time in polyphosphoric acid (PPA). The structure and the membrane swelling behavior were investigated by small angle X-ray scattering (SAXS). It was found that fewer hydrophilic segments resulted in fewer and smaller hydrophilic domains during structural reorganization upon water swelling. The analogous swelling behavior

Cuihua Li; Jianhong Liu; Caizheng Zhu; Qianling Zhang; Zhongkuan Luo; Rong Guan

2010-01-01

73

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

74

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

75

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

E-print Network

, New Haven, CT 06510, United States a r t i c l e i n f o Article history: Received 23 August 2012 stability Non-polar electrostatics a b s t r a c t Asphaltene precipitation occurs in petroleum fluids under suggests that resins contain several fused five- and six-carbon rings in addition to alkyl chains [2

Firoozabadi, Abbas

76

Synthetic resin-bound truncated Candida antarctica lipase B for production of fatty acid alkyl esters by transesterification of corn and soybean oils with ethanol or butanol.  

PubMed

A gene encoding a synthetic truncated Candida antarctica lipase B (CALB) was generated via automated PCR and expressed in Saccharomyces cerevisiae. Western blot analysis detected five truncated CALB variants, suggesting multiple translation starts from the six in-frame ATG codons. The longest open reading frame, which corresponds to amino acids 35-317 of the mature lipase, appeared to be expressed in the greatest amount. The truncated CALB was immobilized on Sepabeads® EC-EP resin and used to produce ethyl and butyl esters from crude corn oil and refined soybean oil. The yield of ethyl esters was 4-fold greater from corn oil than from soybean oil and was 36% and 50% higher, respectively, when compared to a commercially available lipase resin (Novozym 435) using the same substrates. A 5:1 (v/v) ratio of ethanol to corn oil produced 3.7-fold and 8.4-fold greater yields than ratios of 15:1 and 30:1, respectively. With corn oil, butyl ester production was 56% higher than ethyl ester production. Addition of an ionic catalytic resin step prior to the CALB resin increased yields of ethyl esters from corn oil by 53% compared to CALB resin followed by ionic resin. The results suggest resin-bound truncated CALB has potential application in biodiesel production using biocatalysts. PMID:22342374

Hughes, Stephen R; Moser, Bryan R; Robinson, Samantha; Cox, Elby J; Harmsen, Amanda J; Friesen, Jon A; Bischoff, Kenneth M; Jones, Marjorie A; Pinkelman, Rebecca; Bang, Sookie S; Tasaki, Ken; Doll, Kenneth M; Qureshi, Nasib; Liu, Siqing; Saha, Badal C; Jackson, John S; Cotta, Michael A; Rich, Joseph O; Caimi, Paolo

2012-05-31

77

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

SciTech Connect

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 the Hanford site. The elution step of the multi-step ion exchange process is typically done with 0.5 M nitric acid. An acid eluant is a potential hazard in the event of a spill, leak, etc. because the high-level waste tanks are made of carbon steel. Corrosion and associated structural damage may ensue. Studies are ongoing to explore non-acid elution as an alternative. Batch contact sorption equilibrium screening tests have been conducted with 36 potential non-acid eluants. The sorption tests involve equilibrating each cesium-containing eluant solution with the sRF resin for 48 hours at 25 C in a shaker oven. In the sorption tests, an eluant is deemed to have a high cesium elution potential if it minimizes cesium sorption onto the sRF resin. The top candidates (based on lowest cesium sorption distribution coefficients) include ammonium carbonate, ammonium carbonate/ammonium hydroxide, ammonium bicarbonate, rubidium carbonate, ammonium acetate, ammonium acetate/ammonium hydroxide, ammonium bicarbonate/ammonium hydroxide, calcium chloride, and magnesium chloride. The next phase of testing for this work will focus on the following down selected eluants: Ammonium carbonate, ammonium acetate, calcium acetate, magnesium acetate, nitric acid, and ammonium hydroxide. The next testing phase is a confirmation of the elution ability of the selected eluants. It will mimic a typical sRF cesium ion exchange process i.e., sorption or loading, caustic wash, water rinse, and elution via batch contact sorption and quasi column caustic wash/water rinse/elution. Due to corrosion concerns, calcium acetate and magnesium acetate will be tested instead of calcium chloride and magnesium chloride respectively. Nitric acid is for benchmarking since it is the baseline sRF eluant. The information at hand indicates ammonium hydroxide, while a weak base, may hold promise as an effective eluant. Hence, its inclusion among the eluants to be studied despite the fact that it was not tested as a stand-alone eluant earlier.

Adu-Wusu, K.; Pennebaker, F.

2010-09-01

78

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

79

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

80

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. PMID:17980422

López-Suevos, Francisco; Dickens, Sabine H.

2008-01-01

81

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

82

Direct esterification of a hydroxyl functional polyester resin with p-hydroxybenzoic acid  

Microsoft Academic Search

Comparison of the physical properties of direct esterified, both purified and unpurified, and standard polyester coatings was undertaken. Clear and pigmented baked enamels, both non-cross-linked and cross-linked, were produced. Results indicate that coating binders containing the unpurified direct esterified resin are potentially superior to conventional binders as they exhibit the outstanding feature of being both hard and flexible. This improvement

Stephen G Boyes; Rodney P Chaplin; Thomas P Davis; Jim Viatos; David P Buxton

2000-01-01

83

Diterpenoid resin acid biosynthesis in conifers: characterization of two cytochrome P450-dependent monooxygenases and an aldehyde dehydrogenase involved in abietic acid biosynthesis.  

PubMed

Abietic acid is a major component of the rosin fraction of oleoresin synthesized by grand fir (Abies grandis), lodgepole pine (Pinus contorta), and many other conifer species as a defensive secretion against insect and pathogen attack. The diterpenoid resin acid is derived from geranylgeranyl pyrophosphate via abietadiene, with subsequent oxidation of the C18-methyl of this olefin to abietadienol, abietadienal, and abietic acid. The pathway was confirmed by administering [1,2-14C]acetic acid to grand fir stems which incorporated the radiolabel into abietadiene, the corresponding alcohol and aldehyde, as well as abietic acid. Three different enzymatic activities, catalyzing the sequential oxidation of the olefin to abietic acid, were demonstrated in cell-free stem extracts of both grand fir and lodgepole pine. The first two oxidation steps were catalyzed by the microsomal fraction and required both oxygen and a reduced pyridine nucleotide (NADPH preferred). Both activities were strongly inhibited by CO (blue light reversible) and were differentially sensitive to several substituted N-heterocyclic inhibitors, suggesting that these two enzymes are distinct, microsomal cytochrome P450-dependent monooxygenases. A third enzymatic activity, catalyzing the oxidation of abietadienal to abietic acid, was located in the soluble protein fraction. This oxidation reaction employed NAD+ as cofactor, but did not require oxygen and was not inhibited by CO, indicating that this last step of abietic acid biosynthesis is catalyzed by an operationally soluble aldehyde dehydrogenase. PMID:8311462

Funk, C; Croteau, R

1994-01-01

84

Improvement of enamel bond strengths for conventional and resin-modified glass ionomers: acid-etching vs. conditioning*  

PubMed Central

Objective: This study deals with the effect of phosphoric acid etching and conditioning on enamel micro-tensile bond strengths (?TBSs) of conventional and resin-modified glass ionomer cements (GICs/RMGICs). Methods: Forty-eight bovine incisors were prepared into rectangular blocks. Highly-polished labial enamel surfaces were either acid-etched, conditioned with liquids of cements, or not further treated (control). Subsequently, two matching pre-treated enamel surfaces were cemented together with one of four cements [two GICs: Fuji I (GC), Ketac Cem Easymix (3M ESPE); two RMGICs: Fuji Plus (GC), RelyX Luting (3M ESPE)] in preparation for ?TBS tests. Pre-treated enamel surfaces and cement-enamel interfaces were analyzed by scanning electron microscopy (SEM). Results: Phosphoric acid etching significantly increased the enamel ?TBS of GICs/RMGICs. Conditioning with the liquids of the cements produced significantly weaker or equivalent enamel ?TBS compared to the control. Regardless of etching, RMGICs yielded stronger enamel ?TBS than GICs. A visible hybrid layer was found at certain enamel-cement interfaces of the etched enamels. Conclusions: Phosphoric acid etching significantly increased the enamel ?TBSs of GICs/RMGICs. Phosphoric acid etching should be recommended to etch the enamel margins before the cementation of the prostheses such as inlays and onlays, using GICs/RMGICs to improve the bond strengths. RMGICs provided stronger enamel bond strength than GICs and conditioning did not increase enamel bond strength. PMID:24190447

Zhang, Ling; Tang, Tian; Zhang, Zhen-liang; Liang, Bing; Wang, Xiao-miao; Fu, Bai-ping

2013-01-01

85

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

86

Preparative-scale amino acid separation by thermal parametric pumping on an ion-exchange resin  

Microsoft Academic Search

Thermal parametric pumping was experimentally investigated for the concentration and separation of amino acids. Previous theories of parametric pumping were improved by taking into account dissociation equilibria in the liquid phase. Experiments were carried out with a mixture of glutamic acid, aspartic acid, serine and threonine in a highly acidic solution (HCl). A multi-component equilibrium model was mainy used to

Gabor Simon; Laszlo Hanak; Georges Grevillot; Tibor Szanya; Gyula Marton

1995-01-01

87

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

88

Catalytic Upgrading of bio-oil using 1-octene and 1-butanol over sulfonic acid resin catalysts  

SciTech Connect

Raw bio-oil from fast pyrolysis of biomass must be refined before it can be used as a transporation fuel, a petroleum refinery feed or for many other fuel uses. Raw bio-oil was upgraded with the neat model olefin, 1-octene, and with 1-octene/1-butanol mixtures over sulfonic acid resin catalysts frin 80 to 150 degrees celisus in order to simultaneously lower water content and acidity and to increase hydrophobicity and heating value. Phase separation and coke formation were key factors limiting the reaction rate during upgrading with neat 1-octene although octanols were formed by 1-octene hydration along with small amounts of octyl acetates and ethers. GC-MS analysis confirmed that olefin hydration, carboxylic acid esterification, acetal formation from aldehydes and ketones and O- and C-alkylations of phenolic compounds occurred simultaneously during upgrading with 1-octene/1-butanol mixtures. Addition of 1-butanol increased olefin conversion dramatically be reducing mass transfer restraints and serving as a cosolvent or emulsifying agent. It also reacted with carboxylic acids and aldehydes/ketones to form esters, and acetals, respectively, while also serving to stabilize bio-oil during heating. 1-Butanol addition also protected the catalysts, increasing catalyst lifetime and reducing or eliminationg coking. Upgrading sharply increased ester content and decreased the amounts of levoglucosan, polyhydric alcohols and organic acids. Upgrading lowered acidity (pH value rise from 2.5 to >3.0), removed the uppleasant ordor and increased hydrocarbon solubility. Water content decreased from 37.2% to < 7.5% dramatically and calorific value increased from 12.6 MJ kg to about 30.0 MJ kg.

Zhang, Zhijun; Wang, Qingwen; Tripathi, Prabhat; Pittman, Charles U.

2011-02-04

89

Preparation and characterization of anion exchange resin decorated with magnetite nanoparticles for removal of p-toluic acid from aqueous solution  

NASA Astrophysics Data System (ADS)

Polystyrene resin was covalently functionalized with diethanolamine and then decorated with magnetite nanoparticles by a novel and simple co-precipitation method using iron(II) sulfate as precursor. The products were characterized by Fourier transform infrared spectroscopy, elemental analysis, X-ray diffraction, Mössbauer spectroscopy, field-emission scanning electron microscopy and vibrating sample magnetometer. Adsorption of p-toluic acid (p-TA) onto magnetite-decorated polystyrene (MAG-PS) was studied and compared with that of diethanolamine-functionalized polystyrene and a commercial anion exchange resin. Results showed that the magnetite nanoparticles with an average size of 20.4 nm were successfully formed on the surface of polystyrene resin, and MAG-PS was exhibited high affinity for the removal of p-TA.

Davarpanah, Morteza; Ahmadpour, Ali; Rohani Bastami, Tahereh

2015-02-01

90

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

91

Characterization of Group V Dubnium Homologs on DGA Extraction Chromatography Resin from Nitric and Hydrofluoric Acid Matrices  

SciTech Connect

Studies of the chemical properties of superheavy elements (SHE) pose interesting challenges due to their short half-lives and low production rates. Chemical systems must have extremely fast kinetics, fast enough kinetics to be able to examine the chemical properties of interest before the SHE decays to another nuclide. To achieve chemistry on such time scales, the chemical system must also be easily automated. Most importantly however, a chemical system must be developed which provides suitable separation and kinetics before an on-line study of a SHE can be performed. Relativistic effects make studying the chemical properties of SHEs interesting due to the impact these effects could have on the SHEs chemical properties. Relativistic effects arise when the velocity of the s orbital electrons approach the speed of light. As this velocity increases, the Bohr radius of the inner electron orbitals decreases and there is an increase in the particles mass. This contraction results in a destabilization of the energy of the outer d and f electron orbitals (5f and 6d in the case of SHE), which can cause these to expand due to their increased shielding from the nuclear charge. Another relativistic effect is the spin-orbit splitting for p, d, and f orbitals into j = 1 {+-} 1/2 states. This can lead most interestingly to a possible increased stability of element 114, which due to large spin-orbit splitting of the 7p orbital and the relativistically stabilized 7p{sub 1/2} and 7s orbital gives rise to a closed shell ground state of 7s{sup 2}7p{sub 1/2}{sup 2}. The homologs of element 105, dubnium (Db), Ta and Nb and the pseudo-homolog Pa, are well known to hydrolyze and form both neutral and non-neutral monoatomic and polyatomic species that may cause issues with extraction from a given chemical system. Early ion-exchange and solvent-extraction studies show mixed results for the behavior of Db. Some studies show Db behaving most similar to Ta, while others show it behaving somewhere between Nb and Pa. Much more recent studies have examined the properties of Db from HNO{sub 3}/HF matrices, and suggest Db forms complexes similar to those of Pa. Very little experimental work into the behavior of element 114 has been performed. Thermochromatography experiments of three atoms of element 114 indicate that the element 114 is at least as volatile as Hg, At, and element 112. Lead was shown to deposit on gold at temperatures about 1000 C higher than the atoms of element 114. Results indicate a substantially increased stability of element 114. No liquid phase studies of element 114 or its homologs (Pb, Sn, Ge) or pseudo-homologs (Hg, Cd) have been performed. Theoretical predictions indicate that element 114 is should have a much more stable +2 oxidation state and neutral state than Pb, which would result in element 114 being less reactive and less metallic than Pb. The relativistic effects on the 7p{sub 1/2} electrons are predicted to cause a diagonal relationship to be introduced into the periodic table. Therefore, 114{sup 2+} is expected to behave as if it were somewhere between Hg{sup 2+}, Cd{sup 2+}, and Pb{sup 2+}. In this work two commercially available extraction chromatography resins are evaluated, one for the separation of Db homologs and pseudo?homologs from each other as well as from potential interfering elements such as Group IV Rf homologs and actinides, and the other for separation of element 114 homologs. One resin, Eichrom's DGA resin, contains a N,N,N',N'-tetra-n-octyldiglycolamide extractant, which separates analytes based on both size and charge characteristics of the solvated metal species, coated on an inert support. The DGA resin was examined for Db chemical systems, and shows a high degree of selectivity for tri-, tetra-, and hexavalent metal ions in multiple acid matrices with fast kinetics. The other resin, Eichrom's Pb resin, contains a di-t-butylcyclohexano 18-crown-6 extractant with isodecanol solvent, which separates analytes based on steric interactions between the cavity of the crown ether and electrostatic interac

Despotopulos, J D; Sudowe, R

2012-02-21

92

Preconcentration and speciation of chromium using a melamine based polymeric sequestering succinic acid resin: its application for Cr(VI) and Cr(III) determination in wastewater.  

PubMed

A new melamine based polymeric sequestering resin was prepared for preconcentration and separation of hexavalent chromium from water, and its sequestering action was investigated. The water-insoluble, cross-linked sequestering resin was formed by reaction with bromosuccinic acid and cross-linking of melamine. The active sequestering group on the resin is NH-(Succinic acid) or salt thereof. The resulting chelating resin was characterized by infrared spectra. The newly prepared resin quantitatively retained Cr(VI) at pH 2.0-4.0 when the flow rate was maintained between 1 and 5 ml min(-1). The retained Cr(VI) was instantaneously eluted with 25 ml of 0.1 M NaOH. The chromium species were determined by a flame atomic absorption spectrometer. The limits of detection for Cr(VI) and Cr(III) were found to be 5.3 and 4.2 microg l(-1), respectively. The precision and accuracy of the proposed procedure was checked by the use synthetic and reference steel samples. The established preconcentration method was successfully applied to the determination and selective separation of Cr(VI) in electroplating industry wastewater. Total concentrations determined by the spectrophotometric method (110.3+/-0.6 g l(-1) Cr(VI) and 1.2+/-0.3 g l(-1) Cr(III)) are compared with those found by FAAS and the obtained results (110.4+/-1.8 g l(-1) Cr(VI) and 1.4+/-0.5 g l(-1) Cr(III)) show good agreement. PMID:18968997

Do?utan, Melek; Filik, Hayati; Tor, Izzet

2003-04-10

93

Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating  

NASA Astrophysics Data System (ADS)

The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on the surface of Mn-Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz-1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite.

Wang, Wenjie; Zang, Chongguang; Jiao, Qingjie

2015-03-01

94

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

95

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

96

Solid phase extraction of some precious metals from hydrochloric acid to polystyrene-divinylbenzene porous resin impregnated with polyoxyethylene-type nonionic surfactant.  

PubMed

The solid phase extraction of gold(III), platinum(II), and palladium(II) to surfactant-impregnated polystyrene-divinylbenzene porous resin (XAD-4) was studied. The extracting media could be prepared just by mixing the resin in aqueous surfactant solutions. XAD-4 impregnated with a nonionic surfactant, polyethylene glycol monooleyl ether, was useful for extracting gold(III) from hydrochloric acid. The extractions of platinum(II) and palladium(II) were improved in the use of XAD-4 impregnated with a nitrogen-containing nonionic surfactant, polyethylene glycol stearyl amine. On the other hand, base metals such as copper(II), cobalt(II), nickel(II) and zinc(II), were hardly extracted. PMID:16259992

Saitoh, Tohru; Suzuki, Syuntaro; Hiraide, Masataka

2005-12-01

97

Effect of acid pre-conditioning and/or delayed light irradiation on enamel bond strength of three resin-modified glass ionomers  

PubMed Central

Background: Polymerization of resin-modified glass-ionomers (RMGIs) is mediated through two competing mechanisms: An acid-base reaction and a light-dependent resin polymerization. Furthermore, pre-conditioning with acid has resulted in an increase in enamel bond strength of some RMGIs. This in vitro study evaluated the effect of pre-conditioning and/or delayed irradiation on bond strength of three RMGIs to enamel. Materials and Methods: In this in vitro study, 144 flat enamel surfaces of human molars were ground using consecutively finer abrasives up to 600-grit silicon carbide paper. Each surface was rinsed and gently air-dried (n =12). The RMGIs (Fuji II LC Improved; Ionolux and Vitremer) were bonded to enamel surfaces using the following protocols: Groups 1: Based on manufacturers’ instructions; Groups 2: Pre-conditioning with phosphoric acid for 30 s; groups 3: A 2-min delay in irradiation; groups 4: Pre-conditioning with acid for 30 s plus a 2-min delay in light activation. After 24-h storage at 37°C and 500 rounds of thermocycling, the samples underwent shear bond strength (SBS) test. Data was analyzed with 3-way ANOVA and Tukey HSD test (? =0.05). Results: There were significant differences between the study groups (P < 0.001). Acid-pre-conditioning increased Fuji II LC SBS values; it significantly decreased SBS values of Vitremer but had no effect on SBS values of Ionolux. Ionolux and Vitremer exhibited decreased enamel bond strength after a delay in light activation (P < 0.05). A 2-min delay in light activation combined with acid pre-conditioning increased RMGI SBS values only for Fuji II LC. Conclusion: Within the limitations of the present study, the effect of acid pre-conditioning, delaying irradiation and both on enamel bond strength of RMGIs was material-dependent. Further investigations are recommended. PMID:24019800

Khoroushi, Maryam; Hosseini-Shirazi, Moeen; Soleimani, Hojatolah

2013-01-01

98

Effect of sodium hypochlorite and peracetic acid on the surface roughness of acrylic resin polymerized by heated water for short and long cycles  

PubMed Central

Objective: To evaluate the surface roughness of acrylic resin submitted to chemical disinfection via 1% sodium hypochlorite (NaClO) or 1% peracetic acid (C2H4O3). Materials and Methods: The disc-shaped resin specimens (30 mm diameter ×4 mm height) were polymerized by heated water using two cycles (short cycle: 1 h at 74°C and 30 min at 100°C; conventional long cycle: 9 h at 74°C). The release of substances by these specimens in water solution was also quantified. Specimens were fabricated, divided into four groups (n = 10) depending on the polymerization time and disinfectant. After polishing, the specimens were stored in distilled deionized water. Specimens were immersed in 1% NaClO or 1% C2H4O3 for 30 min, and then were immersed in distilled deionized water for 20 min. The release of C2H4O3 and NaClO was measured via visual colorimetric analysis. Roughness was measured before and after disinfection. Roughness data were subjected to two-way ANOVA and Tukey's test. Results: There was no interaction between polymerization time and disinfectant in influencing the average surface roughness (Ra, P = 0.957). Considering these factors independently, there were significant differences between short and conventional long cycles (P = 0.012), but no significant difference between the disinfectants hypochlorite and C2H4O3 (P = 0.366). Visual colorimetric analysis did not detect release of substances. Conclusion: It was concluded that there was the difference in surface roughness between short and conventional long cycles, and disinfection at acrylic resins polymerized by heated water using a short cycle modified the properties of roughness. PMID:25512737

Sczepanski, Felipe; Sczepanski, Claudia Roberta Brunnquell; Berger, Sandrine Bittencourt; Consani, Rafael Leonardo Xediek; Gonini-Júnior, Alcides; Guiraldo, Ricardo Danil

2014-01-01

99

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

100

Kinetic, equilibrium and thermodynamic studies on sorption of uranium and thorium from aqueous solutions by a selective impregnated resin containing carminic acid.  

PubMed

In this work, the removal of uranium and thorium ions from aqueous solutions was studied by solid-liquid extraction using an advantageous extractant-impregnated resin (EIR) prepared by loading carminic acid (CA) onto Amberlite XAD-16 resin beads. Batch sorption experiments using CA/XAD-16 beads for the removal of U(VI) and Th(IV) ions were carried out as a function of several parameters, like equilibration time, metal ion concentration, etc. The equilibrium data obtained from the sorption experiments were adjusted to the Langmuir isotherm model and the calculated maximum sorption capacities in terms of monolayer sorption were in agreement with those obtained from the experiments. The experimental data on the sorption behavior of both metal ions onto the EIR beads fitted well in both Bangham and intra-particle diffusion kinetic models, indicating that the intra-particle diffusion is the rate-controlling step. The thermodynamic studies at different temperatures revealed the feasibility and the spontaneous nature of the sorption process for both uranium and thorium ions. PMID:25576783

Rahmani-Sani, Abolfazl; Hosseini-Bandegharaei, Ahmad; Hosseini, Seyyed-Hossein; Kharghani, Keivan; Zarei, Hossein; Rastegar, Ayoob

2015-04-01

101

Effect of a self-etching primer and phosphoric acid etching on the bond strength of 4-META/MMA-TBB resin to human enamel.  

PubMed

The purpose of this study was to evaluate the shear bond strength and durability of 4-META/MMA-TBB resin to human enamel. A self-etching primer that contained 4-META (Teeth Primer, TP) and 35-45% or 60-65% concentrations of phosphoric acid (K-Etchant Gel, KE, and Super Bond C&B Red Activator, RA) were used as the surface treatment agents. A methyl methacrylate (MMA)-based self-polymerizing resin (Super-Bond C&B) was used as a luting agent. The shear bond strength was determined both pre and post thermocycling. The results were statistically analyzed with a non-parametric procedure. The post-thermocycling shear bond strength of the TP group was significantly higher than that of other groups, and that of the KE group was significantly higher compared with the RA group. These results demonstrated that 4-META was effective. Furthermore, when the degree of tooth demineralization was compared, surface treatment with less demineralization using TP was the most effective treatment. PMID:25740168

Nogawa, Hiroshi; Koizumi, Hiroyasu; Saiki, Osamu; Hiraba, Haruto; Nakamura, Mitsuo; Matsumura, Hideo

2015-04-01

102

Separation of Hydroxycitric Acid Lactone from Fruit Pectins and Polyhydroxyphenols on Poly(4-Vinylpyridine) Weak-Base Resin  

Microsoft Academic Search

Poly(4-vinylpyridine) (PVP) has been used for the separation of hydroxycitric acid lactone (HCAL) from polyhydroxyphenols and fruit pectins, as the study has relevance to the problem of extraction of the antiobesity substance hydroxycitric acid from Garcinia cambogia fruits, a rich source of the acid. PVP has been used both in free-base form and in protonated or salt form as a

M. CHANDA; G. L. REMPEL

2000-01-01

103

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2011 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2011-04-01

104

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2014 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2014-04-01

105

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2012 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2012-04-01

106

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2013 CFR

...paragraph (d) of this section. (1) Nylon 66 resins are manufactured by the condensation...hexamethylene-diamine and sebacic acid. (3) Nylon 66/610 resins are manufactured by the...condensation of equal-weight mixtures of nylon 66 salts and nylon 610 salts....

2013-04-01

107

Method of curing unsaturated polymer resin  

Microsoft Academic Search

An unsaturated polyester resin in contact with a vulcanized rubber is ; haadened by ionization radiation. The unsaturated polyester resin includes ; unsaturated dibasic acid such as maleic anhydride and phthalic anhydride, ; reaction products with dihydric alcohols such as ethylene glycol and propylene ; glycol, the compounds that can be obtained by dissolving into vinyl monomer such ; as

K. Goto; K. Araki; T. Sasaki

1970-01-01

108

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

109

Reusable chelating resins concentrate metal ions from highly dilute solutions  

NASA Technical Reports Server (NTRS)

Column chromatographic method uses new metal chelating resins for recovering heavy-metal ions from highly dilute solutions. The absorbed heavy-metal cations may be removed from the chelating resins by acid or base washes. The resins are reusable after the washes are completed.

Bauman, A. J.; Weetal, H. H.; Weliky, N.

1966-01-01

110

Methyl Jasmonate Induces Traumatic Resin Ducts, Terpenoid Resin Biosynthesis, and Terpenoid Accumulation in Developing Xylem of Norway Spruce Stems  

Microsoft Academic Search

Norway spruce (Picea abies L. Karst) produces an oleoresin characterized by a diverse array of terpenoids, monoterpenoids, sesquiterpenoids, and diterpene resin acids that can protect conifers against potential herbivores and pathogens. Oleoresin accumulates constitutively in resin ducts in the cortex and phloem (bark) of Norway spruce stems. De novo formation of traumatic resin ducts (TDs) is observed in the developing

Diane Martin; Dorothea Tholl; Jonathan Gershenzon; Jorg Bohlmann

2002-01-01

111

Biological Ion Exchanger Resins  

PubMed Central

Utilizing Escherichia coli as the prototype of an ion-accumulating cell, the ion exchange isotherm is introduced as a concise method of characterizing biological ion exchange events. The ion exchange isotherm for the alkali cation exchange, K ? Na, is described. The total charge profile of this bacterium is compiled and compared for bacteria in the Na form and in the K form. Macromolecule fixed charge was found to provide 80% of the counter ions that pair with potassium. Therefore, in its physiological state, 80% of the cell potassium in E. coli is associated with an ion exchange site on a macromolecule. The primary cation exchange sites are found to be about equally divided between carboxylate and phosphate sites indicating that E. coli is a bifunctional resin with respect to cation exchange. During substrate-dependent cation accumulation (“active transport”), phosphate esters and organic acids were shown to accumulate. One may conclude that the role of intermediate metabolism in “active transport” is to increase the ion exchange capacity of the biological resin by the production of charged metabolites that sorb to the framework of the resin. PMID:4943652

Damadian, Raymond

1971-01-01

112

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

113

Contact allergy due to colophony. (IX). Sensitization studies with further products isolated after oxidative degradation of resin acids and colophony.  

PubMed

Degradation of abietic, levopimaric and dehydroabietic acids after exposure to air and light over a period of one to several months, as well as examination of degraded French tall oil rosin and Portuguese colophony, led to the isolation of numerous oxidation products. These compounds were synthesized and consigned to experimental sensitization in guinea pigs. From 20 substances studied as acids or as their methyl esters, in the present and preceding paper, at least 2 can be named: 8,12-peroxydo-delta 13(14)-dihydroabietic acid and 12 alpha-hydroxyabietic acid, that contribute a great deal to colophony allergy by both their sensitizing capacity and their determined concentration in the mixture of degradation products. We recommend the preparation of a new mixture of colophony oxidation products for patch testing in the diagnosis of contact allergy to colophony. PMID:8112061

Hausen, B M; Börries, M; Budianto, E; Krohn, K

1993-11-01

114

Determining resin/fiber content of laminates  

NASA Technical Reports Server (NTRS)

Article discusses procedure where hydrazine is used to extract graphite fibers from cured polyimide resin. Method does not attack graphite fibers and is faster than hot-concentrated-acid digestion process.

Garrard, G. G.; Houston, D. W.

1979-01-01

115

Resin hybrid composite laminates  

SciTech Connect

Hybrid composites are generally referred to as the materials that combine two or more fibers in a suitable binding resin. Resin hybrid composites described in this paper utilize two or more resins with a suitable reinforcement. The resins are rigid resin and flexible resins. The elongation of the rigid resin is less than 2% and elongation of the flexible resins are varied between 25% to 100% by blending a very flexible resin with the rigid resin. Test laminates are fabricated by using either glass, carbon or aramid reinforcement in a layered sequence. This produces rigid-flexible-rigid and flexible-rigid-flexible laminates. These laminates are tested for impact, compression, flexural and inter-laminar strengths. Results show that the resin hybriding provides a wide choice of mechanical properties to the composite industry.

Bhatnagar, A.

1986-01-01

116

Ligand-Exchange Chromatography of Some Amino Acids on Co(II)Loaded CMDAE-Sporopollenin Resin  

Microsoft Academic Search

Sporopollenin obtained from Lycopodium clavatum has been modified as an ligand-exchange material. In this study, the possibility of using sporopollenin as a ligand exchanger in the chromatographic separation of amino acids is examined. Since sporopollenin has important advantages (it is stable to chemicals and has a constant mesh size), it can be used as a column packing material. By first

A. Ayar; S. Yildiz; E. Pehlivan

1995-01-01

117

Influence of air-abrasion executed with polyacrylic acid-Bioglass 45S5 on the bonding performance of a resin-modified glass ionomer cement.  

PubMed

The aim of this study was to test the microtensile bond strength (?TBS), after 6 months of storage in PBS, of a resin-modified glass ionomer cement (RMGIC) bonded to dentine pretreated with Bioglass 45S5 (BAG) using various etching and air-abrasion techniques. The RMGIC (GC Fuji II LC) was applied onto differently treated dentine surfaces followed by light curing for 30 s. The specimens were cut into matchsticks with cross-sectional areas of 0.9 mm(2). The ?TBS of the specimens was measured after 24 h or 6 months of storage in PBS and the results were statistically analysed using two-way anova and the Student-Newman-Keuls test (? = 0.05). Further RMCGIC-bonded dentine specimens were used for interfacial characterization, micropermeability, and nanoleakage analyses by confocal microscopy. The RMGIC-dentine interface layer showed no water absorption after 6 months of storage in PBS except for the interdiffusion layer of the silicon carbide (SiC)-abraded/polyacrylic acid (PAA)-etched bonded dentine. The RMGIC applied onto dentine air-abraded with BAG/H(2)O only or with BAG/PAA-fluid followed by etching procedures (10% PAA gel) showed no statistically significant reduction in ?TBS after 6 months of storage in PBS. The abrasion procedures performed using BAG in combination with PAA might be a suitable strategy to enhance the bonding durability and the healing ability of RMGIC bonded to dentine. PMID:22409224

Sauro, Salvatore; Watson, Timothy F; Thompson, Ian; Toledano, Manuel; Nucci, Cesare; Banerjee, Avijit

2012-04-01

118

Acylation of Aromatic Ethers Using Different Carboxylic Acid Anhydrides as Acylating Agents in the Presence of Nontoxic, Noncorrosive Resin Amberlyst 15 as a Solid Acid Catalyst  

Microsoft Academic Search

Friedel–Crafts acylation of aromatic ethers, anisole, 2-methoxynaphthalene, and dimethoxybenzenes with different acid anhydrides is carried out in the presence of an inexpensive and nonhazardous solid acid, Amberlyst 15. The catalyst is reusable, thus making the process environmentally friendly.

Manoj A. Pande; Shriniwas D. Samant

2011-01-01

119

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

120

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. PMID:22991638

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

2012-01-01

121

Hydrolyzable polyester resins, varnishes and coating compositions containing the same  

DOEpatents

Preparation of hydrolyzable polyester resin comprising reacting polycarboxylic acid and polyhydric alcohol components, which is characterized by using, as at least part of said polyhydric alcohol component, a metallic salt of hydroxy carboxylic acid of the formula defined and effecting the polycondensation at a temperature which is no more than the decomposition temperature of said metallic salt. The polyester resins are useful as resinous vehicle of varnishes and antifouling paints.

Yamamori, Naoki (Minoo, JP); Yokoi, Junji (Nara, JP); Yoshikawa, Motoyoshi (Nara, JP)

1984-01-01

122

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

123

Cloning and expression of a CYP720B orthologue involved in the biosynthesis of diterpene resin acids in Pinus brutia.  

PubMed

Cytochrome P450 monooxygenases mediate a broad range of oxidative reactions involved in the biosynthesis of both primary and secondary metabolites in plants. Until now, only two P450 genes, CYP720B1 from Pinus taeda and CYP720B4 from Picea sitchensis, have been functionally characterised and described in the literature. The purpose of this study was to describe the cloning and expression of CYP720B from Pinus brutia due to its suggested role in the synthesis of bioactive compounds used for chemical defence against insects. A PCR product of the P. brutia CYP720B gene was cloned into the pCR8/GW/TOPO cloning vector. After optimising the sequence for codon usage in yeast, it was transferred into the inducible expression vector pYES-DEST52 and transfected into the S. cerevisiae INVSc1 strain. Sequence analysis showed that the P. brutia CYP720B gene contains an open reading frame of 1,464 nucleotides, which encodes a 53,570 Da putative protein of 487 amino acid residues. The putative protein contains the classic heme-binding sequence motif that is conserved in all P450 enzymes. It shares 99 and 61 % identity with the deduced amino acid sequences of CYP720B1 from Pinus taeda and CYP720B4 from Picea sitchensis, respectively. Recombinant CYP720B protein expression was confirmed using western blot analysis. Furthermore, recombinant CYP720B was functionally active, showing a Soret peak at approximately 448 nm in the reduced CO difference spectra. These data suggest that the cloned gene is an orthologue of CYP720B in P. brutia and might be involved in DRA biosynthesis. PMID:25394757

Semiz, Asli; Sen, Alaattin

2015-03-01

124

Evolution of Conifer Diterpene Synthases: Diterpene Resin Acid Biosynthesis in Lodgepole Pine and Jack Pine Involves Monofunctional and Bifunctional Diterpene Synthases1[W][OA  

PubMed Central

Diterpene resin acids (DRAs) are major components of pine (Pinus spp.) oleoresin. They play critical roles in conifer defense against insects and pathogens and as a renewable resource for industrial bioproducts. The core structures of DRAs are formed in secondary (i.e. specialized) metabolism via cycloisomerization of geranylgeranyl diphosphate (GGPP) by diterpene synthases (diTPSs). Previously described gymnosperm diTPSs of DRA biosynthesis are bifunctional enzymes that catalyze the initial bicyclization of GGPP followed by rearrangement of a (+)-copalyl diphosphate intermediate at two discrete class II and class I active sites. In contrast, similar diterpenes of gibberellin primary (i.e. general) metabolism are produced by the consecutive activity of two monofunctional class II and class I diTPSs. Using high-throughput transcriptome sequencing, we discovered 11 diTPS from jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta). Three of these were orthologous to known conifer bifunctional levopimaradiene/abietadiene synthases. Surprisingly, two sets of orthologous PbdiTPSs and PcdiTPSs were monofunctional class I enzymes that lacked functional class II active sites and converted (+)-copalyl diphosphate, but not GGPP, into isopimaradiene and pimaradiene as major products. Diterpene profiles and transcriptome sequences of lodgepole pine and jack pine are consistent with roles for these diTPSs in DRA biosynthesis. The monofunctional class I diTPSs of DRA biosynthesis form a new clade within the gymnosperm-specific TPS-d3 subfamily that evolved from bifunctional diTPS rather than monofunctional enzymes (TPS-c and TPS-e) of gibberellin metabolism. Homology modeling suggested alterations in the class I active site that may have contributed to their functional specialization relative to other conifer diTPSs. PMID:23370714

Hall, Dawn E.; Zerbe, Philipp; Jancsik, Sharon; Quesada, Alfonso Lara; Dullat, Harpreet; Madilao, Lina L.; Yuen, Macaire; Bohlmann, Jörg

2013-01-01

125

Evolution of conifer diterpene synthases: diterpene resin acid biosynthesis in lodgepole pine and jack pine involves monofunctional and bifunctional diterpene synthases.  

PubMed

Diterpene resin acids (DRAs) are major components of pine (Pinus spp.) oleoresin. They play critical roles in conifer defense against insects and pathogens and as a renewable resource for industrial bioproducts. The core structures of DRAs are formed in secondary (i.e. specialized) metabolism via cycloisomerization of geranylgeranyl diphosphate (GGPP) by diterpene synthases (diTPSs). Previously described gymnosperm diTPSs of DRA biosynthesis are bifunctional enzymes that catalyze the initial bicyclization of GGPP followed by rearrangement of a (+)-copalyl diphosphate intermediate at two discrete class II and class I active sites. In contrast, similar diterpenes of gibberellin primary (i.e. general) metabolism are produced by the consecutive activity of two monofunctional class II and class I diTPSs. Using high-throughput transcriptome sequencing, we discovered 11 diTPS from jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta). Three of these were orthologous to known conifer bifunctional levopimaradiene/abietadiene synthases. Surprisingly, two sets of orthologous PbdiTPSs and PcdiTPSs were monofunctional class I enzymes that lacked functional class II active sites and converted (+)-copalyl diphosphate, but not GGPP, into isopimaradiene and pimaradiene as major products. Diterpene profiles and transcriptome sequences of lodgepole pine and jack pine are consistent with roles for these diTPSs in DRA biosynthesis. The monofunctional class I diTPSs of DRA biosynthesis form a new clade within the gymnosperm-specific TPS-d3 subfamily that evolved from bifunctional diTPS rather than monofunctional enzymes (TPS-c and TPS-e) of gibberellin metabolism. Homology modeling suggested alterations in the class I active site that may have contributed to their functional specialization relative to other conifer diTPSs. PMID:23370714

Hall, Dawn E; Zerbe, Philipp; Jancsik, Sharon; Quesada, Alfonso Lara; Dullat, Harpreet; Madilao, Lina L; Yuen, Macaire; Bohlmann, Jörg

2013-02-01

126

Devolatilization of polymer resins  

NASA Technical Reports Server (NTRS)

Commercial silicon resin was devolatilized by vacuum distillation, cured at room temperature and tested favorably for outgassing criteria. Applications of the devolatilized resin are potting compounds and conformal coatings.

Seidenberg, B.; Park, J.; Clatterbuck, C.

1972-01-01

127

Detoxification of lignocellulose hydrolysates with ion-exchange resins  

Microsoft Academic Search

Lignocellulose hydrolysates contain fermentation inhibitors causing decreased ethanol production. The inhibitors include phenolic\\u000a compounds, furan aldehydes, and aliphatic acids. One of the most efficient methods for removing inhibiting compounds prior\\u000a to fermentation is treatment of the hydrolysate with ion-exchange resins. The performance and detoxification mechanism of\\u000a three different resins were examined: an anion exchanger, a cation exchanger, and a resin

Nils-Olof Nilvebrant; Anders Reimann; Simona Larsson; Leif J. Jönsson

2001-01-01

128

Phenol-Crotonaldehyde Resins. III. Curing Behavior with Hexamethylenetetramine  

Microsoft Academic Search

Solid thermoplastic resins were prepared by acid-catalyzed condensation of phenol and crotonaldehyde (both crude and distilled). The thermal and curing properties were compared with the conventional phenol-formaldehyde (PF) novolak resins. Phenol-crotonaldehyde (PC) resins were found to be thermoplastic even after curing with the crosslinking agent hexamethylenetetramine up to 160°C. This curing behavior was observed irrespective of the purity of the

R. N. Dongre; S. Ponrathnam; V. M. Nadkarni

1987-01-01

129

Deacidification of a synthetic oil with an anion exchange resin  

Microsoft Academic Search

Esters of trimethylolpropane were prepared by reaction of trimethylolpropane with erucic acid. Unreacted erucic acid was eliminated\\u000a by fixation on an anion exchange resin to produce an oil with a low free fatty acid content. The authors describe the deacidification\\u000a of the reaction product by Lewatit MP500A and MP600 resins in a fixed-bed reactor or in a stirred reactor. The

Valérie Eychenne; Zéphirin Mouloungui

1998-01-01

130

Advanced thermoplastic resins, phase 2  

NASA Technical Reports Server (NTRS)

High temperature structural resins are required for use on advanced aerospace vehicles as adhesives and composite matrices. NASA-Langley developed polyimide resins were evaluated as high temperature structural adhesives for metal to metal bonding and as composite matrices. Adhesive tapes were prepared on glass scrim fabric from solutions of polyamide acids of the semicrystalline polyimide LARC-CPI, developed at the NASA-Langley Research Center. Using 6Al-4V titanium adherends, high lap shear bond strengths were obtained at ambient temperature (45.2 MPa, 6550 psi) and acceptable strengths were obtained at elevated temperature (14.0 MPa, 2030 psi) using the Pasa-Jell 107 conversion coating on the titanium and a bonding pressure of 1.38 MPa (200 psi). Average zero degree composite tensile and compressive strengths of 1290 MPa (187 ksi) and 883 MPa (128 ksi) respectively were obtained at ambient temperature with unsized AS-4 carbon fiber reinforcement.

Brown, A. M.; Hill, S. G.; Falcone, A.

1991-01-01

131

High Temperature Transfer Molding Resins  

NASA Technical Reports Server (NTRS)

High temperature resins containing phenylethynyl groups that are processable by transfer molding have been prepared. These phenylethynyl containing oligomers were prepared from aromatic diamines containing phenylethynyl groups and various ratios of phthalic anhydride and 4-phenylethynlphthalic anhydride in glacial acetic acid to form a mixture of imide compounds in one step. This synthetic approach is advantageous since the products are a mixture of compounds and consequently exhibit a relatively low melting temperature. In addition, these materials exhibit low melt viscosities which are stable for several hours at 210-275 C, and since the thermal reaction of the phenylethynyl group does not occur to any appreciable extent at temperatures below 300 C, these materials have a broad processing window. Upon thermal cure at approximately 300-350 C, the phenylethynyl groups react to provide a crosslinked resin system. These new materials exhibit excellent properties and are potentially useful as adhesives, coatings, films, moldings and composite matrices.

Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

2000-01-01

132

Adsorption behaviour of metal ions on hydroximate resins.  

PubMed

Some new chelating ion-exchange resins containing a hydroxamic acid moiety attached to a divinylbenzene styrene (DVBS) copolymer, i.e. glycine hydroximate in DVBS (GH-DVBS). anthranilic acid hydroximate in DVBS (AAHDVBS), malonic acid dihydroximate in DVBS (MAH-DVBS) and iminodiacetic acid dihydroximate in DVBS (IDAAH-DVBS). have been synthesized and their various physicochemical characteristics studied. The degree of retention of metal ions by the resins at equilibrium has been determined in terms of the molar distribution coefficient (k(d)). In general, the resins having a dihydroximate moiety are found to be more efficient compared to monohydroximate resins. However, it is of interest to note that the monohydroximate derivative of amino acid (GH-DVBS) showed better metal retention capability than the dihydroximate of carboxylic acid (MAH-DVBS). The selectivity of the resins for transition and highly charged metal ions is quite high compared to that for alkaline earth metals. All the synthesized resins can be utilized for the separation of a mixture of metal ions because the differences in the distribution coefficient values are large enough to permit good separations on columns. However, the GH-DVBS resin was tried for the separation of copper cobalt and copper nickel mixtures at pH 5.5 using the column mode of operation. PMID:18966686

Ahuja, M; Rai, A K; Mathur, P N

1996-11-01

133

Disinfection of viable Pseudomonas stutzeri in ultrapure water with ion exchange resins  

Microsoft Academic Search

This study describes the disinfection of gram-negative bacteria, Pseudomonas stutzeri, isolated from ultrapure water (total organic carbon 5 ppb; effluent resistivity, > 18 M? cm at 25°C) with ion exchange resins using a batchwise procedure. A single bed of strong base anion exchange resin (SBAER) in OH? form shows disinfection ability; however, a bed of strong acid cation exchange resin

Nae Matsuda; Wataru Agui; Keizo Ogino; Norimichi Kawashima; Tokeru Watanabe; Hideki Sakai; Masahiko Abe

1996-01-01

134

Synthesis of improved polyester resins  

NASA Technical Reports Server (NTRS)

Eighteen aromatic unsaturated polyester prepolymers prepared by a modified interfacial condensation technique were investigated for their solubility in vinyl monomers and ability to provide high char yield forming unsaturated polyester resins. The best resin system contained a polyester prepolymer of phthalic, fumaric and diphenic acids reacted with 2,7-naphthalene diol and 9,9-bis(4-hydroxyphenyl)fluorene. This prepolymer is very soluble in styrene, divinyl benzene, triallyl cyanurate, diallyl isophthalate and methylvinylpyridine. It provided anaerobic char yields as high as 41 percent at 800 C. The combination of good solubility and char yield represents a significant improvement over state-of-the-art unsaturated polyester resins. The majority of the other prepolymers had only low or no solubility in vinyl monomers. Graphite composites from this prepolymer with styrene were investigated. The cause for the observed low shear strengths of the composites was not determined, however 12-week aging of the composites at 82 C showed that essentially no changes in the composites had occurred.

Mcleod, A. H.; Delano, C. B.

1979-01-01

135

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

136

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

137

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

138

Preparation and characterization of chitosan-grafted-poly(2-amino-4,5-pentamethylene-thiophene-3-carboxylic acid N'-acryloyl-hydrazide) chelating resin for removal of Cu(II), Co(II) and Ni(II) metal ions from aqueous solutions.  

PubMed

The graft copolymerization of ethylacrylate (EA) onto chitosan initiated by potassium persulphate and Mohr's salt combined redox initiator system in limited aqueous medium was carried out in heterogeneous media. Moreover, modification of the grafted chitosan was carried out by reaction of the ester group (-COOEt) with 2-amino-4,5-pentamethylene-thiophene-3-carboxylic acid hydrazide which eventually produce chitosan-grafted-poly(2-amino-4,5-pentamethylene-thiophene-3-carboxylic acid N'-acryloyl-hydrazide) (chitosan-g-ATAH) chelating resin. The application of the modified resin for metal ion uptake was studied using Cu(2+), Co(2+) and Ni(2+) ions. The modified chelating resins were characterized using FTIR spectroscopy, SEM and X-ray diffraction. PMID:21277322

Bekheit, M M; Nawar, N; Addison, A W; Abdel-Latif, D A; Monier, M

2011-05-01

139

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2011 CFR

...conditions: (a) Polysulfide polymer-polyepoxy resins are the reaction products of liquid polysulfide polymers and polyfunctional...Naphthalene sulfonic acid-formaldehyde condensate, sodium salt Sodium dibutyl naphthalene sulfonate Wetting agent....

2011-04-01

140

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

141

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

142

Chemical and biological investigation of Araucaria heterophylla Salisb. resin.  

PubMed

Three labdane diterpenes, namely lambda-8(17),14-diene, 13-epicupressic acid, and 13-Oacetyl-13-epicupressic acid, were isolated from the resin collected from stem exudates of Araucaria heterophylla Salisb. (Araucariaceae). The isolated compounds were identified using different spectroscopic methods (1H NMR, 13C NMR, HMQC, HMBC and COSY). The resin extract showed antiulcerogenic activity against ethanol-induced stomach ulcers in Sprauge Dawely rats using ranitidine as standard. In addition, the resin and the isolated compounds showed variable cytotoxic activities against breast (MCF7) and colon (HCT116) cancer cell lines. PMID:20158152

Abdel-Sattar, Essam; Monem, Azza R Abdel; Ezzat, Shahira M; El-Halawany, Ali M; Mouneir, Samar M

2009-01-01

143

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

144

CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN  

SciTech Connect

This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two {approx}11 mL beds in columns in a lead-lag arrangement. The first two campaigns used Savannah River Site (SRS) Tank 2F nonradioactive simulant while the latter two were fed with actual dissolved salt in the Savannah River National Laboratory (SRNL) Shielded Cells. Both radioactive cycles ran to cesium breakthrough of the lead column. The resin beds saw in excess of 400 bed volumes of feed in each cycle. Resin disposal plans in tank farm processing depend on characterizations of resin used with actual tank feed. Following a final 30 bed volume (BV) elution with nitric acid, the resin beds were found to contain detectable chromium, barium, boron, aluminum, iron, sodium, sulfur, plutonium, cesium, and mercury. Resin affinity for plutonium is important in criticality safety considerations. Cesium-137 was found to be less than 10E+7 dpm/g of resin, similar to past work with sRF resin. Sulfur levels are reasonably consistent with other work and are expected to represent sulfur chemistry used in the resin manufacture. There were low but detectable levels of technetium, americium, and curium. Toxicity Characteristic Leaching Procedure (TCLP) work on the used (eluted) resin samples showed significant contents of mercury, barium, and chromium. One resin sample exceeded the TCLP level for mercury while the other metals were below TCLP levels. TCLP organics measurements indicated measurable benzene in one case, though the source was unknown. Results of this work were compared with other work on similar sRF resin characterizations in this report. This is the first work to quantify mercury on sRF resin. Resin mercury content is important in plans for the disposition of used sRF resin. Mercury speciation in high level waste (HLW) is unknown. It may be partly organic, one example being methyl mercury cation. Further study of the resin's affinity for mercury is recommended.

Nash, C.; Duignan, M.

2010-02-23

145

Biocompatibility of composite resins  

PubMed Central

Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concerns about their degradation and substances which may be segregated into oral cavity. PMID:23372592

Mousavinasab, Sayed Mostafa

2011-01-01

146

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

147

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

148

Adsorption of uranium ions by resins with amidoxime and amidoxime/carboxyl group prepared by radiation-induced polymerization  

NASA Astrophysics Data System (ADS)

In order to recover uranium ions from seawater, chelate-type resins with amidoxime and amidoxime/carboxylic acid groups were prepared by radiation-induced polymerization of acrylonitrile (AN) and AN/acrylic acid and by subsequent amidoximation of cyano group of poly(AN), respectively. The resins were characterized by FT-IR, FT-Raman, solid-state 13C-NMR, SEM, and elemental analysis, respectively. The adsorption rate of uranium ion by resins with the amidoxime/carboxylic acid group were higher than that of resins with the amidoxime group. The adsorption of uranium ions in artificial seawater to chelate-type resins was also examined.

Choi, Seong-Ho; Choi, Min-Seok; Park, Yong-Tae; Lee, Kwang-Pill; Kang, Hee-Dong

2003-06-01

149

Acetylene terminated matrix resins  

NASA Technical Reports Server (NTRS)

The synthesis of resins with terminal acetylene groups has provided a promising technology to yield high performance structural materials. Because these resins cure through an addition reaction, no volatile by-products are produced during the processing. The cured products have high thermal stability and good properties retention after exposure to humidity. Resins with a wide variety of different chemical structures between the terminal acetylene groups are synthesized and their mechanical properties studied. The ability of the acetylene cured polymers to give good mechanical properties is demonstrated by the resins with quinoxaline structures. Processibility of these resins can be manipulated by varying the chain length between the acetylene groups or by blending in different amounts of reactive deluents. Processing conditions similar to the state-of-the-art epoxy can be attained by using backbone structures like ether-sulfone or bis-phenol-A. The wide range of mechanical properties and processing conditions attainable by this class of resins should allow them to be used in a wide variety of applications.

Goldfarb, I. J.; Lee, Y. C.; Arnold, F. E.; Helminiak, T. E.

1985-01-01

150

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

Code of Federal Regulations, 2010 CFR

...Polyesters *Furan Resins Glyoxal-Urea Formaldehyde Textile Resin *Ketone-Formaldehyde Resins *Melamine Resins *Phenolic Resins *Polyacetal Resins Polyacrylamide *Polyurethane Prepolymers *Polyurethane Resins...

2010-07-01

151

Study on dehydrochlorination of waste poly (vinyl chloride) resins by microwave irradiation  

NASA Astrophysics Data System (ADS)

Waste poly (vinyl chloride: PVC) resins are experimentally dehydrochlorinated by microwave irradiation. The following unique results are obtained: (1) plasticizer in PVC resin absorbs microwave power more effectively than PVC polymer. The higher the plasticizer content in PVC resin, the higher is the dehydrochlorination reaction (2) low PVC polymer content materials such as cushion floor require high microwave irradiation power to secure a high dehydrochlorination yield, (3) calcium carbonate in PVC resin reacts with released hydrochloric acid gas and results calcium chloride during microwave irradiation, (4) additives in PVC resin strongly influence dehydrochlorination yield, (5) it is evidenced that the PVC copolymer is also dehydrochlorinated by microwave irradiation.

Moriwaki, Saburo; Qian, Qingrong; Sunohara, Satoshi; Machida, Motoi; Tatsumoto, Hideki

152

Fiber reinforced thermoplastic resin matrix composites  

NASA Technical Reports Server (NTRS)

Polyimide polymer composites having a combination of enhanced thermal and mechanical properties even when subjected to service temperatures as high as 700.degree. F. are described. They comprise (a) from 10 to 50 parts by weight of a thermoplastic polyimide resin prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and (b) from 90 to 50 parts by weight of continuous reinforcing fibers, the total of (a) and (b) being 100 parts by weight. Composites based on polyimide resin formed from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and pyromellitic dianhydride and continuous carbon fibers retained at least about 50% of their room temperature shear strength after exposure to 700.degree. F. for a period of 16 hours in flowing air. Preferably, the thermoplastic polyimide resin is formed in situ in the composite material by thermal imidization of a corresponding amide-acid polymer prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane. It is also preferred to initially size the continuous reinforcing fibers with up to about one percent by weight of an amide-acid polymer prepared from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane. In this way imidization at a suitable elevated temperature results in the in-situ formation of a substantially homogeneous thermoplastic matrix of the polyimide resin tightly and intimately bonded to the continuous fibers. The resultant composites tend to have optimum thermo-mechanical properties.

Jones, Robert J. (Inventor); Chang, Glenn E. C. (Inventor)

1989-01-01

153

[Study of purity tests for silicone resins].  

PubMed

In the 8th edition of Japan's Specifications and Standards for Food Additives, the purity test for silicone resins requires the determination of the refractive index and kinetic viscosity of the extracted silicone oil, and allows for only a limited amount of silicon dioxide. In the purity test, carbon tetrachloride is used to separate the silicone oil and silicon dioxide. To exclude carbon tetrachloride, methods were developed for separating the silicone oil and silicon dioxide from silicone resin, which use hexane and 10% n-dodecylbenzenesulfonic acid in hexane. For silicone oil, the measured refractive index and kinetic viscosity of the silicone oil obtained from the hexane extract were shown to be equivalent to those of the intact silicone oil. In regard to silicon dioxide, it was confirmed that, following the separation with 10% n-dodecylbenzenesulfonic acid in hexane, the level of silicon dioxide in silicone resin can be accurately determined. Therefore, in this study, we developed a method for testing the purity of silicone resins without the use of carbon tetrachloride, which is a harmful reagent. PMID:23243991

Sato, Kyoko; Otsuki, Noriko; Ohori, Akio; Chinda, Mitsuru; Furusho, Noriko; Osako, Tsutomu; Akiyama, Hiroshi; Kawamura, Yoko

2012-01-01

154

Graphite fiber reinforced thermoplastic resins  

NASA Technical Reports Server (NTRS)

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). Tensile, flexural, interlaminar shear, creep and impact strengths were measured for polysulfone, polyarylsulfone and a state-of-the-art epoxy resin samples. In general, the thermoplastic resins exhibited environmental degradation resistance equal to or superior to the reference epoxy resin. Demonstration of the utility and quality of a graphite/thermoplastic resin system was accomplished by successfully thermoforming a simulated compressor blade and a fan exit guide vane.

Novak, R. C.

1975-01-01

155

The role of maleic anhydride in adhesive resin cements.  

PubMed

The adherence of resin cements depends upon, among other factors, the polar interactions across the interface: resin cement/restorative material. The polar interactions may be augmented by inclusion of polar additives such as maleic anhydride to the cement monomer. However, maleic anhydride is slowly converted to maleic acid when exposed to an aqueous environment. This may affect mechanical properties of such a cement in a negative way. It was the aim of the present investigation to analyze the role of maleic anhydride dissolved in the monomer of resin cements. The resin cement monomers used were common methacrylates, to which maleic anhydride in amounts of up to 30 mol% was added. Polymerization initiators were included to make the materials dual curing. Finally, the preparations were mixed with silanated fillers. The adherence energy of the cements bonded to a chromium-cobalt alloy was assessed by means of the double cantilever beam test. The strength and stiffness of the resin cements were recorded at base line and after two months storage in water. The initial adherence energy increased by a factor of about two as a result of addition of maleic anhydride. However, resin cements containing maleic anhydride suffered significant reductions in long-term adherence, strength and stiffness. These reductions were particularly pronounced in non-irradiated specimens. The use of resin cements containing maleic anhydride is not a viable means of conveying adhesiveness to resin cements. PMID:9708691

Asmussen, E; Peutzfeldt, A

1998-08-01

156

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.  

PubMed

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. The order of elution for the model cations was H+ > Li+ > Na+ > NH4+ > Ca2+ > > Mg2+. A sharp and highly symmetrical peak was obtained for H+ and this was attributed to the capacity of H2Y2(2-) to receive and bind H+. H+ was detected conductiometrically and detector response (reduction in conductivity as a result of H+ +H2Y2- --> H3Y-) was linearly proportional to the concentration of H+ in the sample. The detection limit for H+ with this IC system was better than 4.7 micromol L(-1). A significant advantage of this method was the ability to separate and determine, in one step, H+ and other cations. The successful determination of H+ and other cation species in real acid-rain samples demonstrated the usefulness of this method. PMID:11393236

Hu, W; Iles, A; Hasebe, K; Matsukami, H; Cao, S; Tanaka, K

2001-05-01

157

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

158

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

159

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

160

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

161

Glycoprotein Enrichment Resin User Manual  

E-print Network

Glycoprotein Enrichment Resin User Manual Cat. No. 635647 PT4050-1 (PR912675) Published 14 January Laboratories, Inc. Version No. PR912675 ATakara Bio Company 2 Glycoprotein Enrichment Resin User Manual I.................................................................................................4 IV. Glycoprotein Enrichment

Lebendiker, Mario

162

Preirradiation grafting of ethylene vinyl acetate copolymer resins  

Microsoft Academic Search

Acrylic acid was graft copolymerised on to EVA powdered resins containing 9%, 18% and 28% vinyl acetate. A preirradiation grafting method was used and the effect on graft level of varying the parameters of gamma irradiation dose (2–50 kGy), dose rate (0.5–5 kGy h?1), monomer concentration (2.5–25%) and grafting time (1–4 h) and temperature (35–98°C) was investigated. The graft copolymer resins

B. J Ringrose; E Kronfli

1999-01-01

163

Boron Isotope Fractionation in Column Chromatography with Glucamine Type Resins  

Microsoft Academic Search

Glucamine type resins have specific affinity toward boric acid and borate ion. Various studies of chromatographic separation of boron isotopes have been carried out, but few have addressed effects of base polymer skeletons. In this study, we used three glucamine type resins, which have different base polymer skeletons: synthesized GMA-DVB-Glu, commercial Diaion CRB02 and Chelest Fiber GRY-L. They were packed

Akinari SONODA; Yoji MAKITA; Takahiro HIROTSU

2006-01-01

164

Barium titanate formation by organic resins formed with mixed citrate  

Microsoft Academic Search

Citric precursors are used to produce BaTiO3, the Ba\\/Ti ratio being fixed by a mixed Ba-Ti citrate. The conditions for its solubility in organic agents (ethylene glycol or ethylene glycol+ citric acid) has been studied and used to investigate various routes of synthesis (resin, spray pyrolysis or films). The transformation from the resin to the mineral phase has been investigated.

J. P. Coutures; P. Odier; C. Proust

1992-01-01

165

Progress in DUV resins  

NASA Astrophysics Data System (ADS)

Starting from general arguments on the relation of polymer structure, transparency at 248 nm, resin hydrophilicity and resist dissolution characteristics, binder systems for novel DUV resists are presented, and the results of their lithographic evaluation are discussed. Phenolic polymers studied include homo- and copolymers of 2-, 3-, and 4- hydroxystyrenes and of their alkyl substituted derivatives for three- component systems, as well as 2- and 4-hydroxyphenylmethacrylates for use in two-component t-BOC-type resists. As an alternative nonphenolic resin, the performance of a maleimide/styrene copolymer in a two- component system is discussed.

Przybilla, Klaus J.; Roeschert, Heinz; Spiess, Walter; Eckes, Charlotte; Chatterjee, Subhankar; Khanna, Dinesh N.; Pawlowski, Georg; Dammel, Ralph R.

1991-06-01

166

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

167

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

168

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

169

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

170

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

171

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

172

Gastroprotective effect of the Mapuche crude drug Araucaria araucana resin and its main constituents  

Microsoft Academic Search

The resin from the tree Araucaria araucana (Araucariaceae) has been used since pre-columbian times by the Mapuche amerindians to treat ulcers. The gastroprotective effect of the resin was assessed in the ethanol–HCl-induced gastric ulcer in mice showing a dose-dependent gastroprotective activity at 100, 200 and 300mg\\/kg per os. The main three diterpene constituents of the resin, namely imbricatolic acid, 15-hydroxyimbricatolal

Guillermo Schmeda-Hirschmann; Luis Astudillo; Jaime Rodríguez; Cristina Theoduloz; Tania Yáñez

2005-01-01

173

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

174

Selective separation of germanium(IV) by 2,3-dihydroxypropyl chitosan resin  

Microsoft Academic Search

2,3-Dihydroxypropyl chitosan resin, prepared from chitosan and a 1,2-diol, adsorbed only germanium(IV) from aqueous solutions containing semimetals over the range of acidic to weakly basic media. The adsorption capacities of the chitosan resin were up to about 1.4mmolg?1. The selective separation of germanium(IV) from tellurium(VI) and boron was achieved with a column method using the chitosan resin. The breakthrough points

Yoshinari Inukai; Toyotaka Chinen; Toshio Matsuda; Yasuhiko Kaida; Seiji Yasuda

1998-01-01

175

In vitro toothbrush-dentifrice abrasion of resin-modified glass ionomers  

Microsoft Academic Search

Objectives. This study was conducted to compare the rate of abrasive wear and change in surface roughness of resin-modified and conventional acid-base glass ionomers when subjected to toothbrush-dentifrice abrasion.Methods. Two resin-modified and two conventional glass ionomers were used. Samples of a high-copper amalgam and a hybrid resin composite were used as reference materials. Specimens of each material were prepared and

Yasuko Momoi; Kunitsugu Hirosaki; Atsushi Kohno; John F. McCabe

1997-01-01

176

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

177

A comparative study of fluoride-releasing adhesive resin materials.  

PubMed

One of the most important and exciting properties of recently introduced dental restorative materials is their ability to release fluoride ions, as this has several advantageous effects on tooth structures. They have been extensively used as fluoride-releasing filling and luting materials. Recently, fluoride-releasing adhesive resins and fluoride-releasing adhesive resin cement have been developed and introduced for clinical use. The purpose of this study was to evaluate the fluoride release from these adhesive resins and the fluoride uptake by both enamel and dentin, as well as the acid-resistance of these tooth structures. Based on our results, we conclude that fluoride-releasing adhesive resins and luting cements are useful for the prevention of initial or secondary caries, especially along the margins of restorations. PMID:12046524

Han, Linlin; Edward, Cruz; Okamoto, Akira; Iwaku, Masaaki

2002-03-01

178

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. PMID:17062742

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

2008-01-01

179

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2012 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2012-04-01

180

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2010 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2010-04-01

181

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2014 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2014-04-01

182

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2011 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2011-04-01

183

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2013 CFR

...4â²-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section...4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified...4?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which...

2013-04-01

184

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

185

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

186

Removal of CdTe in acidic media by magnetic ion-exchange resin: a potential recycling methodology for cadmium telluride photovoltaic waste.  

PubMed

Sulfonated magnetic microspheres (PSt-DVB-SNa MPs) have been successfully prepared as adsorbents via an aqueous suspension polymerization of styrene-divinylbenzene and a sulfonation reaction successively. The resulting adsorbents were confirmed by means of Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope equipped with an energy dispersive spectrometer (SEM-EDS) and vibrating sample magnetometer (VSM). The leaching process of CdTe was optimized, and the removal efficiency of Cd and Te from the leaching solution was investigated. The adsorbents could directly remove all cations of Cd and Te from a highly acidic leaching solution of CdTe. The adsorption process for Cd and Te reached equilibrium in a few minutes and this process highly depended on the dosage of adsorbents and the affinity of sulfonate groups with cations. Because of its good adsorption capacity in strong acidic media, high adsorbing rate, and efficient magnetic separation from the solution, PSt-DVB-SNa MPs is expected to be an ideal material for the recycling of CdTe photovoltaic waste. PMID:25128764

Zhang, Teng; Dong, Zebin; Qu, Fei; Ding, Fazhu; Peng, Xingyu; Wang, Hongyan; Gu, Hongwei

2014-08-30

187

Environment and Genotype Affect Sweetpotato Storage Root Periderm Resin Glycoside Content  

Technology Transfer Automated Retrieval System (TEKTRAN)

Resin glycosides are complex compounds composed primarily of fatty acids and sugars that contribute to allelopathic potential and pest resistance in sweetpotato. Total periderm resin glycoside (PRG) contents of 10 sweetpotato (Ipomoea batatas L.) clones grown in three different field trials was det...

188

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

189

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

190

Retrofit for Plastic Resin Driers  

E-print Network

RETROFIT FOR PLASTIC RESIN DRIERS BABU JOSEPH PH.D. Supervising Engineer Southern California Edison Company, Irwindale, California GEORGE THURO Thuro, & Associates, Costa Mesa, California Plastic resins used in injection molding have... temperature units, and vary depending on the resin, the mold and the molding process. Typically the drier is set for the worst possible conditions. So there are opportunities for energy savings. This study conducted by Southern California Edison Company...

Joseph, B.; Thuro, G.

191

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins  

Code of Federal Regulations, 2012 CFR

...HAP) From the Manufacture of Amino/Phenolic Resins 2 Table...Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63...HAP) From the Manufacture of Amino/Phenolic Resins Organic... Yes Cresol and cresylic acid (mixed) 1319-77-3...

2012-07-01

192

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins  

Code of Federal Regulations, 2011 CFR

...HAP) From the Manufacture of Amino/Phenolic Resins 2 Table...Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63...HAP) From the Manufacture of Amino/Phenolic Resins Organic... Yes Cresol and cresylic acid (mixed) 1319-77-3...

2011-07-01

193

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins  

Code of Federal Regulations, 2014 CFR

...HAP) From the Manufacture of Amino/Phenolic Resins 2 Table...Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63...HAP) From the Manufacture of Amino/Phenolic Resins Organic... Yes Cresol and cresylic acid (mixed) 1319-77-3...

2014-07-01

194

40 CFR Table 2 to Subpart Ooo of... - Known Organic Hazardous Air Pollutants (HAP) From the Manufacture of Amino/Phenolic Resins  

Code of Federal Regulations, 2013 CFR

...HAP) From the Manufacture of Amino/Phenolic Resins 2 Table...Pollutant Emissions: Manufacture of Amino/Phenolic Resins Pt. 63...HAP) From the Manufacture of Amino/Phenolic Resins Organic... Yes Cresol and cresylic acid (mixed) 1319-77-3...

2013-07-01

195

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.’ PMID:21217945

Nandini, Suresh

2010-01-01

196

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

197

Methyl Jasmonate Induces Traumatic Resin Ducts, Terpenoid Resin Biosynthesis, and Terpenoid Accumulation in Developing Xylem of Norway Spruce Stems1  

PubMed Central

Norway spruce (Picea abies L. Karst) produces an oleoresin characterized by a diverse array of terpenoids, monoterpenoids, sesquiterpenoids, and diterpene resin acids that can protect conifers against potential herbivores and pathogens. Oleoresin accumulates constitutively in resin ducts in the cortex and phloem (bark) of Norway spruce stems. De novo formation of traumatic resin ducts (TDs) is observed in the developing secondary xylem (wood) after insect attack, fungal elicitation, and mechanical wounding. Here, we characterize the methyl jasmonate-induced formation of TDs in Norway spruce by microscopy, chemical analyses of resin composition, and assays of terpenoid biosynthetic enzymes. The response involves tissue-specific differentiation of TDs, terpenoid accumulation, and induction of enzyme activities of both prenyltransferases and terpene synthases in the developing xylem, a tissue that constitutively lacks axial resin ducts in spruce. The induction of a complex defense response in Norway spruce by methyl jasmonate application provides new avenues to evaluate the role of resin defenses for protection of conifers against destructive pests such as white pine weevils (Pissodes strobi), bark beetles (Coleoptera, Scolytidae), and insect-associated tree pathogens. PMID:12114556

Martin, Diane; Tholl, Dorothea; Gershenzon, Jonathan; Bohlmann, Jörg

2002-01-01

198

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

199

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

200

Uptake of actinides and other ions by Diphosil, a new silica-based chelating ion exchange resin  

SciTech Connect

After adsorption of actinides on a phosphonic acid resin, it may be desirable to leave the actinides on the resin. It may be preferable that the polymeric resin matrix be replaced by an inorganic material, in order to prevent formation of radiolytic gases from the organic polymer. A new version of the Diphonix resin has been prepared, where the chelating diphosphonic acid groups are grafted to a silica support. This material is called Diphosil, for Diphonix on silica. This paper reports some results on equilibrium and kinetics of uptake of a number of actinide species and other metal ions of nuclear, environmental, or hydrometallurgical interest by Diphosil.

Chiarizia, R.; Horwitz, E.P.; D`Arcy, K.A. [Argonne National Lab., IL (United States); Alexandratos, S.D.; Trochimczuk [Tennessee Univ., Knoxville, TN (United States). Dept. of Chemistry

1996-06-01

201

An Engineering Evaluation of Spherical Resorcinol Formaldehyde Resin  

SciTech Connect

A small column ion exchange (SCIX) system has been proposed for removal of cesium from caustic, supernatant, and dissolved salt solutions stored or generated from high-level tank wastes at the US Department of Energy (DOE) Hanford Site and Savannah River Sites. In both instances, deployment of SCIX systems, either in-tank or near-tank, is a means of expediting waste pretreatment and dispositioning with minimal or no new infrastructure requirements. Conceptually, the treatment approach can utilize a range of ion exchange media. Previously, both crystalline silicotitanate (CST), an inorganic, nonelutable sorbent, and resorcinol-formaldehyde (RF), an organic, elutable resin, have been considered for cesium removal from tank waste. More recently, Pacific Northwest National Laboratory (PNNL) evaluated use of SuperLig{reg_sign} 644, an elutable ion exchange medium, for the subject application. Results of testing indicate hydraulic limitations of the SuperLig{reg_sign} resin, specifically a high pressure drop through packed ion exchange columns. This limitation is likely the result of swelling and shrinkage of the irregularly shaped (granular) resin during repeated conversions between sodium and hydrogen forms as the resin is first loaded then eluted. It is anticipated that a similar flow limitation would exist in columns packed with conventional, granular RF resin. However, use of spherical RF resin is a likely means of mitigating processing limitations due to excessive pressure drop. Although size changes occur as the spherical resin is cycled through loading and elution operations, the geometry of the resin is expected to effectively mitigate the close packing that leads to high pressure drops across ion exchange columns. Multiple evaluations have been performed to determine the feasibility of using spherical RF resin and to obtain data necessary for design of an SCIX process. The work performed consisted of examination of radiation effects on resin performance, quantification of cesium adsorption performance as a function of operating temperature and pH, and evaluation of sodium uptake (titration) as function of pH and counteranion concentration. The results of these efforts are presented in this report. Hydraulic performance of the resin and the use of eluant alternatives to nitric acid have also been evaluated and have been reported elsewhere (Taylor 2009, Taylor and Johnson 2009).

Birdwell Jr, Joseph F [ORNL; Lee, Denise L [ORNL; Taylor, Paul Allen [ORNL; Collins, Robert T [ORNL; Hunt, Rodney Dale [ORNL

2010-09-01

202

Four new triterpenoids isolated from the resin of Garcinia hanburyi.  

PubMed

Four new triterpenoids, 2-O-acetyl-3-O-(4'-O-acetyl)-?-l-arabinopyranosylmaslinic acid (1), 2-O-acetyl-3-O-(3'-O-acetyl)-?-l-arabinopyranosylmaslinic acid (2), 2-O-acetyl-3-O-(3',4'-O-diacetyl)-?-l-arabinopyranosylmaslinic acid (3), and 3-O-(3'-O-acetyl)-?-l-arabinopyranosyloleanolic acid (4), together with six known triterpenoids, 3-O-(4'-O-acetyl)-?-l-arabinopyranosyloleanolic acid (5), maslinic acid (6), 2-O-acetylmaslinic acid (7), 3-O-acetylmaslinic acid (8), betulinic acid (9), and 2?-hydroxy-3?-O-acetylbetulinic acid (10), were isolated from the EtOAc extract of Garcinia hanburyi resin. Their structures were elucidated by analysis of the spectroscopic data and chemical methods. PMID:24392659

Wang, Hong-Min; Liu, Qun-Fang; Zhao, Yi-Wu; Liu, Shuang-Zhu; Chen, Zhen-Hua; Zhang, Ru-Jun; Wang, Zhen-Zhong; Xiao, Wei; Zhao, Wei-Min

2014-01-01

203

Investigating the Use of Ion Exchange Resins for Processing Biodiesel Feedstocks  

E-print Network

feedstocks. Specifically, this research explored using ion exchange resins to remove free fatty acids (FFA) from soybean and waste cooking oils, catalyze transesterification of soybean oil, and catalyze in-situ conversion of dried algal biomass to biodiesel...

Jamal, Yousuf 1973-

2012-11-27

204

21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.  

Code of Federal Regulations, 2012 CFR

...G in table 2 of § 176.170(c), and with foods of Types VIII and IX without use temperature restriction. Styrene-isobutylene copolymer Terpene resins consisting of polymers of ?-pinene, ?-pinene, and/or dipentene; acid value less...

2012-04-01

205

21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.  

Code of Federal Regulations, 2013 CFR

...G in table 2 of § 176.170(c), and with foods of Types VIII and IX without use temperature restriction. Styrene-isobutylene copolymer Terpene resins consisting of polymers of ?-pinene, ?-pinene, and/or dipentene; acid value less...

2013-04-01

206

21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.  

Code of Federal Regulations, 2014 CFR

...G in table 2 of § 176.170(c), and with foods of Types VIII and IX without use temperature restriction. Styrene-isobutylene copolymer Terpene resins consisting of polymers of ?-pinene, ?-pinene, and/or dipentene; acid value less...

2014-04-01

207

21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.  

Code of Federal Regulations, 2011 CFR

...G in table 2 of § 176.170(c), and with foods of Types VIII and IX without use temperature restriction. Styrene-isobutylene copolymer Terpene resins consisting of polymers of ?-pinene, ?-pinene, and/or dipentene; acid value less...

2011-04-01

208

Boron recovery from clay waste using Diaion CRB?02 resin  

Microsoft Academic Search

A two?step process for boron recovery from clay waste is proposed in the present work. The leachate obtained after the clay waste was leached with sulphuric acid solution was treated with Diaion CRB?02 – a boron?specific resin for the separation of boron from the alkaline species in the leachate. The batch studies showed that a maximum boron recovery of about

?. K?pçak; M. Özdemir

2010-01-01

209

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

210

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

211

Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments  

PubMed Central

Objective: The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. Materials and Methods: A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the restorations were removed out leaving only middle part. One side of the cavity was finished with course diamond bur and the other was air-abraded with 50 ?m Al2O3. They were randomly divided into four groups (n = 10) to receive: Group 1: Adper Single Bond 2; Group 2: All Bond 3; Group 3: ClearfilSE; Group 4: BeautiBond, before being repaired with the same resin composite (Filtek Z250). The specimens were re-thermocycled (1000×), sealed with nail varnish, stained with 0.5% basic fuchsin, sectioned mesiodistally and photographed digitally. The extent of dye penetration was measured by image analysis software (ImageJ) for both bur-finished and air-abraded surfaces at resin-tooth and resin-resin interfaces. The data were analyzed statistically. Results: BeautiBond exhibited the most microleakage at every site. Irrespective of adhesive and initial composite type, air-abrasion showed less microleakage except for BeautiBond. The type of initial repaired restorative material did not affect the microleakage. BeautiBond adhesive may not be preferred in resin composite repair in terms of microleakage prevention. Conclusions: Surface treatment with air-abrasion produced the lowest microleakage scores, independent of the adhesive systems and the pre-existing resin composite type. Pre-existing composite type does not affect the microleakage issue. All-in-one adhesive resin (BeautiBond) may not be preferred in resin composite repair in terms of microleakage prevention. PMID:25713491

Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan

2015-01-01

212

Microshear bond strength of composite resins to enamel and porcelain substrates utilizing unfilled versus filled resins  

PubMed Central

Background: Failures such as marginal discoloration and composite chipping are still the problems of tooth-colored restorations on the substrate of enamel and porcelain, which some of these problems are consequently as a result of failures in the bonding layer. Using filled resin has been recently introduced to increase the bond strength of this layer. The aim of this study was to compare the microshear bond strength (?-SBS) of composite resins to enamel incubated in periods of 24 h and 9 months and porcelain with unfilled resin and flowable composites (filled resin). Materials and Methods: In this in vitro study, two groups of 75 enamel samples with different storage times (24 h and 9 months) and a group of 75 porcelain samples were used. They were divided into 5 experimental groups of 15 samples in each. Composite cylinders in tygon tubes were bonded on the surface of acid-etched enamel and pretreated porcelain. Wave, Wave MV, Wave HV, Grandioflow and Margin Bond were used as bonding agents. The ?-SBS was measured at the speed of 1.0 mm/min. The bond strengths were analyzed with one-way analysis of variance (ANOVA) test followed by Tukey test. P < 0.05 was selected as the level of statistical significance in this study. Results: The results showed that for enamel (24 h), the ?-SBS of the Wave MV and Wave HV groups were significantly lower than the Margin Bond group. Tukey test indicated the absence of a significant difference between the ?-SBS of the Wave group and the Margin Bond group. However, the ?-SBS of the Grandioflow group was significantly higher than the one for the Margin Bond as a bonding agent. In enamel (9 months), there was a significant difference between the Grandioflow and Margin Bond groups. Regarding bonding to the porcelain the one-way ANOVA test did not show a significant difference among the groups. Conclusion: This study revealed that flowable composites (filled resins) can be used instead of unfilled resins in bonding composite resins to enamel and porcelain substrates. PMID:25540657

Najafi-Abrandabadi, Ahmad; Najafi-Abrandabadi, Siamak; Ghasemi, Amir; Kotick, Philip G.

2014-01-01

213

Degradation of resin composites in a simulated deep cavity.  

PubMed

The aim of this study was to analyze the sorption and solubility of a nanofilled (Filtek Z350) and a midifilled (Filtek P60) resin composite in oral environment-like substances, in a simulated deep cavity. A cylindrical cavity prepared in a bovine incisor root was incrementally filled with resin composites. The obtained resin composite cylinders were cut perpendicularly to the axis to obtain 1-mm-thick discs that were divided into fifteen groups (n=5) according to depth (1, 2, 3, 4 and 5 mm) and immersion media (distilled water - DW, artificial saliva - AS and lactic acid - LA). The sorption and solubility were calculated based on ISO 4049:2000. Additionally, the degree of conversion (DC%) was calculated by FT-IR spectroscopy. Data were analyzed using multifactor analysis of variance (MANOVA) followed by Tukey's HSD post-hoc test and linear regression analysis (a=0.05). The DC% was higher for the midifilled resin composite and was negatively influenced by cavity depth (p<0.05). The nanofilled resin composite presented higher sorption and solubility than did the midifilled (p<0.05). The immersion media influenced the sorption and the solubility as follows: LA>AS>DW, (p<0.05). Both phenomena were influenced by cavity depth, with the sorption and solubility increasing from 1 to 5 mm (p<0.05). The degradation of resin composite restorations may be greater in the deepest regions of class II restorations when the composite is exposed to organic acids present in the oral biofilm (lactic acid). PMID:25590201

Gonçalves, Luana; Amaral, Cristiane Mariote; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes; Silva, Eduardo Moreira da

2014-12-01

214

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

215

Tubular Occlusion Optimizes Bonding of Hydrophobic Resins to Dentin  

Microsoft Academic Search

Although hydrophobic resins may be bonded to acid-etched dentin with an ethanol wet-bonding technique, the protocol is sensitive to moisture contamination when bonding is performed in deep dentin. This study tested the hypothesis that the use of oxalate or poly(glutamic) acid-modified, diluted ceramicrete (PADC) for dentinal tubule occlusion prevents fluid contamination and improves the bonding of an experimental hydrophobic adhesive

F. T. Sadek; D. H. Pashley; M. Ferrari; F. R. Tay

2007-01-01

216

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

217

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

218

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

219

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

220

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

221

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

222

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...

223

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

224

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

225

Methane production using resin-wafer electrodeionization  

DOEpatents

The present invention provides an efficient method for creating natural gas including the anaerobic digestion of biomass to form biogas, and the electrodeionization of biogas to form natural gas and carbon dioxide using a resin-wafer deionization (RW-EDI) system. The method may be further modified to include a wastewater treatment system and can include a chemical conditioning/dewatering system after the anaerobic digestion system. The RW-EDI system, which includes a cathode and an anode, can either comprise at least one pair of wafers, each a basic and acidic wafer, or at least one wafer comprising of a basic portion and an acidic portion. A final embodiment of the RW-EDI system can include only one basic wafer for creating natural gas.

Snyder, Seth W; Lin, YuPo; Urgun-Demirtas, Meltem

2014-03-25

226

Liquid monobenzoxazine based resin system  

DOEpatents

The present invention provides a liquid resin system including a liquid monobenzoxazine monomer and a non-glycidyl epoxy compound, wherein the weight ratio of the monobenzoxazine monomer to the non-glycidyl epoxy compound is in a range of about 25:75 to about 60:40. The liquid resin system exhibits a low viscosity and exceptional stability over an extended period of time making its use in a variety of composite manufacturing methods highly advantageous.

Tietze, Roger; Nguyen, Yen-Loan; Bryant, Mark

2014-10-07

227

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

228

Cariogenic Bacteria Degrade Dental Resin Composites and Adhesives  

PubMed Central

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.

2013-01-01

229

Biological activity of some naturally occurring resins, gums and pigments against in vitro LDL oxidation.  

PubMed

Naturally occurring gums and resins with beneficial pharmaceutical and nutraceutical properties were tested for their possible protective effect against copper-induced LDL oxidation in vitro. Chiosmastic gum (CMG) (Pistacia lentiscus var. Chia resin) was the most effective in protecting human LDL from oxidation. The minimum and maximum doses for the saturation phenomena of inhibition of LDL oxidation were 2.5 mg and 50 mg CMG (75.3% and 99.9%, respectively). The methanol/water extract of CMG was the most effective compared with other solvent combinations. CMG when fractionated in order to determine a structure-activity relationship showed that the total mastic essential oil, collofonium-like residue and acidic fractions of CMG exhibited a high protective activity ranging from 65.0% to 77.8%. The other natural gums and resins (CMG resin 'liquid collection', P. terebinthus var. Chia resin, dammar resin, acacia gum, tragacanth gum, storax gum) also tested as above, showed 27.0%-78.8% of the maximum LDL protection. The other naturally occurring substances, i.e. triterpenes (amyrin, oleanolic acid, ursolic acid, lupeol, 18-a-glycyrrhetinic acid) and hydroxynaphthoquinones (naphthazarin, shikonin and alkannin) showed 53.5%-78.8% and 27.0%-64.1% LDL protective activity, respectively. The combination effects (68.7%-76.2% LDL protection) of ursolic-, oleanolic- and ursodeoxycholic- acids were almost equal to the effect (75.3%) of the CMG extract in comparable doses. PMID:12748987

Andrikopoulos, Nikolaos K; Kaliora, Andriana C; Assimopoulou, Andreana N; Papapeorgiou, Vassilios P

2003-05-01

230

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

231

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

232

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

233

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

234

Pictet-spengler reaction using ion-exchange resin as a catalyst and support for 'catch and release' purification.  

PubMed

The Pictet-Spengler reaction between tryptamine and aldehydes was catalyzed by Dowex 50W-X4 acidic ion-exchange resin. The products were obtained from the resin in high purity by 'catch and release' without the need for separate chromatographic purification. PMID:21307579

Izumi, Minoru; Kido, Takeshi; Murakami, Miyu; Nakajima, Shuhei; Ganesan, A

2011-01-01

235

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

236

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. PMID:23571321

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

2013-01-01

237

The adsorption of lead and copper from aqueous solution on modified peat-resin particles.  

PubMed

Raw peat was modified with sulfuric acid, then mixed modified with resin to prepare the modified peat-resin particles. Using the batch experimental systems, the removal of heavy metals (copper and lead) on the modified peat-resin particles was investigated. The data of the adsorption isotherm could be fitted by the Langmuir equation well. The adsorption rate of heavy metals on modified peat-resin particles was very swift. The removal processes of heavy metals on modified peat-resin particles could be well described by pseudo-second order model. The adsorption rate of lead was affected by the initial heavy metal concentration, initial pH, particle size, agitation speed and particle mass. In the adsorption of heavy metals (lead and copper) on the modified peat-resin particles, ion exchange was the major reaction mechanism. Desorption data showed that the lead adsorbed by modified peat-resin particle could be desorbed by 0.5 N or 1.0 N HNO3. The desorption rate was swift. The experiments indicated that the modified peat-resin particles have great potential for the removal of heavy metals from wastewater. PMID:15499788

Sun, Q Y; Lu, P; Yang, L Z

2004-01-01

238

Modeling Ion-Exchange Processing With Spherical Resins For Cesium Removal  

SciTech Connect

The spherical Resorcinol-Formaldehyde and hypothetical spherical SuperLig(r) 644 ion-exchange resins are evaluated for cesium removal from radioactive waste solutions. Modeling results show that spherical SuperLig(r) 644 reduces column cycling by 50% for high-potassium solutions. Spherical Resorcinol Formaldehyde performs equally well for the lowest-potassium wastes. Less cycling reduces nitric acid usage during resin elution and sodium addition during resin regeneration, therefore, significantly decreasing life-cycle operational costs. A model assessment of the mechanism behind ''cesium bleed'' is also conducted. When a resin bed is eluted, a relatively small amount of cesium remains within resin particles. Cesium can bleed into otherwise decontaminated product in the next loading cycle. The bleed mechanism is shown to be fully isotherm-controlled vs. mass transfer controlled. Knowledge of residual post-elution cesium level and resin isotherm can be utilized to predict rate of cesium bleed in a mostly non-loaded column. Overall, this work demonstrates the versatility of the ion-exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. This evaluation justifies further development of a spherical form of the SL644 resin.

Hang, T.; Nash, C. A.; Aleman, S. E.

2012-09-19

239

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

240

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2010 CFR

...fluoride resins. Polyvinylidene fluoride resins may be safely used...section, the polyvinylidene fluoride resins consist of basic resins...polymerization of vinylidene fluoride. (b) The finished food-contact...with the solvents distilled water, 50 percent (by...

2010-04-01

241

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

242

Distribution Coefficients (Kd Values) for Waste Resins Generated from the K and L Disassembly Basin Facilities  

SciTech Connect

The objective of this study was to measure 14C, 129I, and 99Tc Kd values of spent resin generated from the K and L Disassembly Basin Facilities. The scope of the work was to conduct Kd measurements of resins combined in the ratio that they are disposed, 42:58 cation:anion. Because it was not known how these spent resins would be buried, it was necessary to measure the Kd values in such a manner as to simulate both trench and vault disposal. This was accomplished by using an acid-rain simulant (a standard U.S. Environmental Protection Agency protocol) and a cement leachate simulant .

Kaplan, D.I.

2002-12-02

243

Solid phase extraction of copper(II) by fixed bed procedure on cation exchange complexing resins.  

PubMed

The efficiency of the metal ion recovery by solid phase extraction (SPE) in complexing resins columns is predicted by a simple model based on two parameters reflecting the sorption equilibria and kinetics of the metal ion on the considered resin. The parameter related to the adsorption equilibria was evaluated by the Gibbs-Donnan model, and that related to the kinetics by assuming that the ion exchange is the adsorption rate determining step. The predicted parameters make it possible to evaluate the breakthrough volume of the considered metal ion, Cu(II), from different kinds of complexing resins, and at different conditions, such as acidity and ionic composition. PMID:20036367

Pesavento, Maria; Sturini, Michela; D'Agostino, Girolamo; Biesuz, Raffaela

2010-02-19

244

Thermal debracketing of orthodontic resins.  

PubMed

Ten commercial brands of orthodontic bonding materials representing three modes of delivery systems (two-paste, no-mix, and powder/liquid) were used to bond stainless steel brackets to bovine teeth. Heat was applied to the bracket, and the temperature at debonding was noted for each type of resin. The two-paste systems required a higher temperature to debond than did the no-mix systems. The powder/liquid system required the lowest temperature. There is a direct relationship between filler content and debonding temperature. There is an inverse exponential relationship between debonding temperature and load needed to cause debracketing. Room-temperature debonding showed failure at the bracket/resin interface with evidence of cohesive enamel fracture. Thermal debonding showed no evidence of overt enamel fracture, and failure site shifted toward the tooth/resin interface. Ceramic brackets required almost twice the time to debracket than did stainless steel brackets. PMID:2194390

Rueggeberg, F A; Lockwood, P

1990-07-01

245

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

246

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3140 Resin applicator. (a) Identification. A resin applicator is a brushlike device...

2010-04-01

247

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 “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

2013-04-01

248

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 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 “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

2010-04-01

249

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2012 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 “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

2012-04-01

250

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2011 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 “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by...

2011-04-01

251

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2014 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 “Intrinsic Viscosity (IV) of Lexan ® Polyestercarbonate Resin by a...

2014-04-01

252

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2011 CFR

...Identification. A resin applicator is a brushlike device intended for use in spreading dental resin on a tooth during application of tooth shade material. (b) Classification. Class I (general controls). The device is exempt...

2011-04-01

253

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2011 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2011-04-01

254

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2014 CFR

...HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2014-04-01

255

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2010 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2010-04-01

256

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2013 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2013-04-01

257

21 CFR 172.280 - Terpene resin.  

Code of Federal Regulations, 2012 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

2012-04-01

258

Improved and selective platinum recovery from spent alpha-alumina supported catalysts using pretreated anionic ion exchange resin.  

PubMed

Improved and selective recovery of platinum from a spent dehydrogenation platinum alpha-alumina supported catalyst using a strong basic ion exchange resin is reported. Platinum and other precious metal group (PMG) complexes are leached using concentrated hydrochloric acid along with about 0.20 vol.% nitric acid as an oxidizing agent from de-coked and crushed spent catalyst. Effects of hydrochloric acid concentration, time, and temperature in leaching stage are investigated. The strong basic anionic resin is treated by sodium hydroxide solution to replace chloride anion by hydroxyl group ion. The supernatant of the leaching process is passed through a fixed column of hydroxylated strong base anionic resin. The treated resin on which the platinum complex is adsorbed is dried and burned in an oxidizing atmosphere at 750-800 degrees C. The recovered gray metallic powder is mainly platinum. Results compared with those obtained from untreated anionic resin show that adsorption of platinum complexes onto the treated anionic resin is more selective and the yield of separation is considerably improved. The breakthrough curves of the pretreated anion exchanger and that of untreated exchange resin reveals that the capacity of the hyroxilated resin is decreased by about 14%. These breakthrough curves can be used for calculation of height of a practical exchange plate (HPEP) for design purposes. PMID:16260084

Shams, K; Goodarzi, F

2006-04-17

259

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

260

Resin-based preparation of HTGR fuels: operation of an engineering-scale uranium loading system  

Microsoft Academic Search

The fuel particles for recycle of ²³³U to High-Temperature Gas-Cooled Reactors are prepared from uranium-loaded carboxylic acid ion exchange resins which are subsequently carbonized, converted, and refabricated. The development and operation of individual items of equipment and of an integrated system are described for the resin-loading part of the process. This engineering-scale system was full scale with respect to a

Haas

1977-01-01

261

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

262

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

263

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...

264

SRM filament wound case resin characterization studies  

NASA Technical Reports Server (NTRS)

The amine cured epoxy wet winding resin used in fabrication of the SRM filament wound case is analyzed. High pressure liquid chromatography (HPSC) is utilized extensively to study lot-to-lot variation in both resin and curing agent. The validity of quantitative hplc methodology currently under development in-process resin/catalyst assay is assessed.

Chou, L. W.

1985-01-01

265

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

266

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

267

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

268

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

269

Polymer properties on resins composed of UDMA and methacrylates with the carboxyl group.  

PubMed

The properties of dental matrix resins have been improved by synthesis of new monomers. However, except for improvements in water-resistance, monomers with better mechanical properties than Bis-GMA and UDMA could not being synthesized. Changing the point of emphasis, we tried to improve the mechanical properties controlling the matrix resin higher structure using noncovalent bonds. We prepared a matrix resin structured by UDMA, which is a high viscosity base monomer with imino groups, and by a low viscosity acidic monomer with carboxyl groups, which permits noncovalent bonds such as hydrogen bonds or electrostatic interaction with imino groups. The maximal mechanical strength for matrix resins structured by UDMA and an acidic monomer was obtained with a composition of imino groups and carboxyl groups at a ratio of 1:1. This mechanical strength value was higher than those obtained with UDMA resin or with a Bis-GMA/TEGDMA/UDMA resin with typical composition. The improvement in mechanical properties may be due to the complex based on noncovalent bonds, between the imino groups of UDMA and the carboxyl groups of the acidic monomers. PMID:11806155

Tanaka, J; Hashimoto, T; Stansbury, J W; Antonucci, J M; Suzuki, K

2001-09-01

270

Devices using resin wafers and applications thereof  

DOEpatents

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

271

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...

272

Effect of wettability of adhesive resins on bonding to dentin.  

PubMed

The purpose of this study was to investigate on human dentin the relationships between, on the one hand, the wettability of five adhesive compounds, characterized by different solubility parameters delta, and on the other, the thickness of the resin impregnated dentin layer (RIL) and the shear bond strength (SBS). Cut dentin surfaces were treated with conditioners of pH 1.25, 3.6 or 7.4. Shear bond strength was measured on 20 specimens each. RIL was determined by scanning electron microscope on specimens fractured perpendicularly to the bonding interface. When resins with delta 32, 30 or 39 (MJ1/2/m3/2) were used RILs were consistently 4 microns and 1 micron on dentin pretreated with the two acidic conditioners. No clearly measurable RIL was shown after application of the conditioner with pH 7.4, and when resins with delta-values of 20 and 25 were applied. For the same adhesive no difference in SBS was found, when applied on the differently conditioned dentin sites. Resins with delta > 30 produced significantly higher SBS than the two adhesives with smaller delta. PMID:9115677

Finger, W J; Inoue, M; Asmussen, E

1994-02-01

273

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

274

The many faces of ion-exchange resins  

SciTech Connect

Ion-exchange resins have been used commercially for over 60 years. Softening and demineralization of water for boiler feed and process use were then, and continue to be, the most familiar and widespread applications of ion-exchange resins throughout the chemical process industries (CPI). Several types of membrane-based technologies, such as electrodialysis, reverse osmosis and, more recently, electrodeionization are recognized as alternative methods for water treatment. Yet, modern versions of ion-exchange resins remain a major player in water treatment. In addition, these versatile materials can be found performing a wide range of tasks in both aqueous and nonaqueous environments. Some of these diverse applications include: acid or base catalysis; manufacture of high-purity solvents and reagent chemicals; separation of by-products of fermentation processes; deacidification of organic solvents; high-purity water production for semiconductor manufacture; recovery of valuable waste from dilute process effluents; controlled release of pharmaceutical products; and chromatography, both on the analytical and the industrial scale. The key to understanding the potential of ion-exchange resins is to look beyond their exchange and adsorptive characteristics, and to see their fundamental nature. In other words, it`s necessary to first consider them as spherical, particulate reactive polymers that perform chemical reactions.

McNutty, J.T. [Rohm and Haas Co., Philadelphia, PA (United States)

1997-06-01

275

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

276

Metal Affinity Resins User Manual  

E-print Network

BD TALONTM Metal Affinity Resins User Manual PT1320-1 (PR34731) Published 29 April 2003 BD Biosciences #12;BD Biosciences Clontech www.bdbiosciences.com Protocol No. PT1320-1 2 Version No. PR34731 BD III. Additional Materials Required 13 IV. Buffers for BD TALONTM Purification & Buffer Kits 17 V

Lebendiker, Mario

277

Process for curing bismaleimide resins  

NASA Technical Reports Server (NTRS)

This invention relates to vinyl pyridine group containing compounds and oligomers, their advantageous copolymerization with bismaleimide resins, and the formation of reinforced composites based on these copolymers. When vinyl pyridines including vinyl stilbazole materials and vinyl styrylpyridine oligomer materials are admixed with bismaleimides and cured to form copolymers the cure temperatures of the copolymers are substantially below the cure temperatures of the bismaleimides alone.

Parker, John A. (inventor); OTHY S.imides alone. (inventor)

1986-01-01

278

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

279

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

280

The use of Diphonix{sup {trademark}} ion exchange resin as a preconcentration step for the lanthanides and actinides in analytical applications  

SciTech Connect

Diphonix ion exchange resin is a chelating ion exchange resin containing sulfonic and gemdiphosphonic acid groups. This resin has a high specificity for the lanthanides and actinides, especially at acidities below pH = 3. Currently, we are investigating new ways to use Diphonix resin as a preconcentration step to separate the lanthanides and actinides from interfering elements present in a variety of environmental matrices. Once the lanthanides and actinides have been separated from the interfering matrix constituents, the elements are removed from the resin and passed through subsequent separation schemes. This presentation will outline the use of Diphonix resin with a variety of problem matrices, and demonstrate its usefulness for analysis of the lanthanides and actinides.

Rollins, A.N.; Thakkar, A.H.; Fern, M.J. [Eichrom Industries, Inc., Darien, IL (United States)] [and others

1995-12-01

281

Phenoxy resins containing pendent ethynyl groups  

NASA Technical Reports Server (NTRS)

As part of an effort on tougher/solvent resistant matrix resins for composites, research was directed towards exploring methods to improve the solvent resistance of linear amorphous thermoplastics. Ethyl reactive groups were placed on the ends of oligomers and pendent along the polymer chain and subsequently thermally reacted to provide crosslinking and thus improvement in solvent resistance. This concept is extended to another thermoplastic, a phenoxy resin. A commercially available phenoxy resin (PKHH) was systematically modified by reaction of the pendent hydroxyl groups on the phenoxy resin with various amounts of 4-ethynylbenzoyl chloride. As the pendent ethynyl group content in the phenoxy resin increased, the cured resin exhibited a higher glass transition temperature, better solvent resistance and less flexibility. The solvent resistance was further improved by correcting a low molecular weight diethynyl compound, 2,2-bis(4-ethynylbenzoyloxy-4'-phenyl)propane, with a phenoxy resin containing pendent ethynyl groups.

Hergenrother, P. M.; Jensen, B. J.; Havens, S. J.

1984-01-01

282

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

283

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

284

Sorption behaviour of lanthanum(III), neodymium(III), terbium(III), thorium(IV) and uranium(VI) on Amberlite XAD-4 resin functionalized with bicine ligands  

Microsoft Academic Search

The complexing properties (capacity, pH effect, breakthrough curve) of a chelating resin, containing bicine ligands, were investigated for La(III), Nd(III), Tb(III), Th(IV) and U(VI). Trace amounts of these metal ions were quantitatively retained on the resin and recovered by eluting with 1 M hydrochloric acid. The capacity of the resin for La(III), Nd(III), Tb(III), Th(IV) and U(VI) was found to

Kapil Dev; Rita Pathak; G. N Rao

1999-01-01

285

Diphonix{trademark} Resin: A review of its properties and applications  

SciTech Connect

The recently developed Diphonix{trademark} resin is a new multifunctional chelating ion exchange resin containing seminally substituted diphosphonic acid ligands chemically bonded to a styrene-based polymeric matrix. Diphonix can be regarded as a dual mechanism polymer, with a sulfonic acid cation exchange group allowing for rapid access, mostly non-specific, of ions into the polymeric network, and the diphosphonic acid group responsible for specificity (recognition) for a number of metal cations. The Diphonix resin exhibits an extraordinarily strong affinity for actinides, especially in the tetra- and hexavalent oxidation states. It has potential applications in TRU and mixed waste treatment and characterization, and in the development of new procedures for rapid actinide preconcentration and separation from environmental samples. Metal uptake studies have been extended to alkaline earth cations, to transition and post transition metal species, and to metal sorption from neutral or near neutral solutions. Also the kinetic behavior of the resin has been investigated in detail. Influence of the most commonly occurring matrix constituents (Na, Ca, Al, Fe, hydrofluoric, sulfuric, oxalic and phosphoric acids) on the uptake of actinide ions has been measured. This review paper summarizes the most important results studies on the Diphonix resin and gives an overview of the applications already in existence or under development in the fields of mixed waste treatment, actinide separation procedures, treatment of radwaste from nuclear power plants, and removal of iron from copper electrowinning solutions.

Chiarizia, R.; Horwitz, E.P. [Argonne National Lab., IL (United States); Alexandratos, S.D. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry; Gula, M.J. [Eichrom Industies, Inc., Darien, IL (United States)

1995-12-31

286

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

287

Evaluation of MMA-4-META-TBB resin as a dental adhesive material.  

PubMed

A new adhesive resin containing a reactive monomer, 4-methacryloxyethyl trimellitate anhydride (4-META) was prepared, and its application to hard tooth tissues and metals was studied. Scanning electron microscopy showed that the average length of 4-META resin tags in enamel and dentin was 22 mu and 40 mu respectively. The tensile adhesive strength between 4-META resin and enamel was about 130 kg/cm2 after etching with 65% phosphoric acid. Its bond strength to dentin treated with a cleaning solution of 10% citric acid and 3% ferric chloride was about 190 kg/cm2. In precious alloys heated at 500 degrees C for 5-10 minutes, a bond strength of more than 100 kg/cm2 was obtained. The precious alloys containing Au, Ag, Pt and Cu should be selected especially for dental restorations. In polished non-precious alloys, the bond strength was greater than 100 kg/cm2. If non-precious alloys were oxidized with HNO3, the bond strength increased to 150-200 kg/cm2. The results suggest that the nickel-chromium alloy used in fixed prosthodontics must be treated chemically before adhesion with 4-META resin, but cobalt-chromium alloy used in removable partial dentures bonds well with 4-META resin without chemical treatment. In conclusion, MMA-4-META-TBB resin seems to be a promising adhesive material in dentistry. PMID:6571588

Kuo, Y S

1984-04-01

288

Analysis of diterpenoic compounds in natural resins applied as binders in museum objects by capillary electrophoresis.  

PubMed

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 such museum objects the identification of the binding media used is undoubtedly of paramount importance. In the present paper, the characterization of these resins based on the pattern of their diterpenoid constituents is carried out by capillary electrophoresis. For separation a background electrolyte which has been initially introduced for the analysis of chlorinated and natural resin acids in waste water was modified and the experimental conditions were adjusted in terms of resolution and analysis time. Separation was carried out in borate buffer at pH 9.25 (ionic strength 20 mmol L(-1)) with methyl-beta-cyclodextrin and sulfobutylether-beta-cyclodextrin as additives to increase selectivity and enhance the solubility of the analytes. With this electrophoretic system the resin acids of interest and larixol acetate--all as anionic cyclodextrin complexes--were separated within 5 min and detected at 200, 250 and 270 nm with a diode array detector. The electrophoretic patterns served for the characterisation of the relevant diterpenoic resins, balsams and copals. Sample pre-treatment was limited to sonication in methanol at 55 degrees C for 30 min. This enables the identification of the resins in mixtures with other binders like plant gums, animal glues or drying oils, even when these media are present in excess. Colophony was identified as resinous constituent of a modelling mass for gilded frames originating from the 19th century. PMID:17521659

Findeisen, Anna; Kolivoska, Viliam; Kaml, Isabella; Baatz, Wolfgang; Kenndler, Ernst

2007-07-20

289

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

290

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

291

Bonding of self-adhesive resin cements to enamel using different surface treatments: bond strength and etching pattern evaluations.  

PubMed

This study evaluated the shear bond strengths and etching patterns of seven self-adhesive resin cements to human enamel specimens which were subjected to one of the following surface treatments: (1) Polishing with #600 polishing paper; (2) Phosphoric acid; (3) G-Bond one-step adhesive; or (4) Phosphoric acid and G-Bond. After surface treatment, the human incisor specimens were bonded to a resin composite using a self-adhesive resin cement [Maxcem (MA), RelyX Unicem (UN), Breeze (BR), BisCem (BI), seT (SE), Clearfil SA Luting (CL)] or a conventional resin cement [ResiCem (RE)]. Representative morphology formed with self-adhesive resin cements showed areas of etched enamel intermingled with areas of featureless enamel. In conclusion, etching efficacy influenced the bonding effectiveness of self-adhesive resin cements to unground enamel, and that a combined use of phosphoric acid and G-Bond for pretreatment of human enamel surfaces improved the bond strength of self-adhesive resin cements. PMID:20668359

Lin, Jie; Shinya, Akikazu; Gomi, Harunori; Shinya, Akiyoshi

2010-08-01

292

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

293

Separation of Lanthanide Ions with Kläui Ligand Resin  

SciTech Connect

Separation and pre-concentration of the desired analyte is often a critical step in many radioanalytical methods. Current procedures for separating and concentrating analytes for detection are complex, and can be both expensive and time consuming. Therefore, the purpose of this research is to develop an alternative method of separating lanthanide ions through the use of an extraction chromatography resin containing a Klaui ligand salt. This research is a continuation of a concerted effort to develop new methods of detecting small concentrations of radionuclides and lanthanides using Klaui ligands. The Klaui ligands, C5Me5Co(OP(OR)2)3- (R=Me, Et, n-Pr) (LOR-), have unique affinity for lanthanide and actinide ions in the presence of competing metal ions. The use of 1 wt% NaLOR (R=Et or n-Pr) adsorbed onto resin support has been shown to extract lanthanide ions from aqueous nitric acid solutions of different concentrations. In order to further evaluate the utility of these materials in radiochemical separation, the selectivity of the resins for the different lanthanide ions was examined by measuring the distribution coefficients (Kd) for a series of lanthanides over a range of solution conditions. Based on prior research with actinide ions, it was hypothesized that the lanthanide ions would bond strongly with the Klaui ligands. The success of this research is important, because it will assist in expanding and improving current automated radiochemical methods, which will decrease the cost of developing and implementing radiochemical methods. To date, Kd values have been determined for Eu+3, Nd+3 and Pr+3 under varying nitric acid (HNO3) concentration, using a resin consisting of 1.0 wt% NaLOPr on Amberlite XAD-7HP. The dependence of the Kd values for Eu+3 has also been examined as a function of the ligand-to-europium ratio and the nitrate concentration. Decreasing Kd values were obtained upon increasing the nitric acid concentration, indicating protonation of the ligand, which competes with binding of the lanthanide ions. As expected, increasing the Klaui ligand-to-europium ratio results in increasing Kd, but no conclusions could be made from these data regarding stoichiometry of the complex formed on the resin. No dependence of the Kd on the nitrate concentration was observed, supporting the notion that the HNO3 dependence is dominated by the presence of the acidic hydronium ion (as opposed to the nitrate ion). Future work will involve the determination of the Kd values for the remainder of the lanthanide series to further assess the potential of the Klaui ligand for intra-group lanthanide separations.

Granger, Trinity D.; Henry, Victoria A.; Latesky, Stanley

2007-07-01

294

Removal of cadmium from fish sauce using chelate resin.  

PubMed

Fish sauce that is prepared from squid organs contains cadmium (Cd), which may be present at hazardous concentrations. Cd molecules are predominantly protein bound in freshly manufactured fish sauce, but are present in a liberated form in air-exposed fish sauce. In the present study, we developed a new method for removing both Cd forms from fish sauce using chelate resin and a previously reported tannin treatment. Sixteen-fold decreases in Cd concentrations were observed (0.78-0.05 mg/100 mL) following the removal of liberated Cd using chelate resin treatment, and the removal of protein-bound Cd using tannin treatment. Major nutritional components of fish sauce were maintained, including free amino acids and peptides, and angiotensin I-converting enzyme inhibitory and antioxidant activities. PMID:25466035

Sasaki, Tetsuya; Araki, Ryohei; Michihata, Toshihide; Kozawa, Miyuki; Tokuda, Koji; Koyanagi, Takashi; Enomoto, Toshiki

2015-04-15

295

Accurate determination of ¹²?I concentrations and ¹²?I/¹³?Cs ratios in spent nuclear resins by Accelerator Mass Spectrometry.  

PubMed

Determining long-lived radionuclide concentrations in radioactive waste has fundamental implications for the long-term management of storage sites. This paper focuses on the measurement of low (129)I contents in ion exchange resins used for primary fluid purification in Pressurised Water Reactors (PWR). Iodine-129 concentrations were successfully determined using Accelerator Mass Spectrometry (AMS) following a chemical procedure which included (1) acid digestion of resin samples in HNO3/HClO4, (2) radioactive decontamination by selective iodine extraction using a new chromatographic resin (CL Resin), and (3) AgI precipitation. Measured (129)I concentrations ranged from 4 to 12 ng/g, i.e. from 0.03 to 0.08 Bq/g. The calculation of (129)I/(137)Cs activity ratios used for routine waste management produced values in agreement with the few available data for PWR resin samples. PMID:24525301

Nottoli, Emmanuelle; Bienvenu, Philippe; Labet, Alexandre; Bourlès, Didier; Arnold, Maurice; Bertaux, Maité

2014-04-01

296

Scintillating 99Tc Selective Ion Exchange Resins  

SciTech Connect

Scintillating technetium (99Tc) selective ion exchange resins have been developed and evaluated for equilibrium capacities and detection efficiencies. These resins can be utilized for the in-situ concentration and detection of low levels of pertechnetate anions (99TcO4-) in natural waters. Three different polystyrene type resin support materials were impregnated with varying amounts of tricaprylmethylammonium chloride (Aliquat 336) extractant, several different scintillating fluors and wavelength shifters. The prepared resins were contacted batch-wise to equilibrium over a wide range of 99TcO4- concentrations in natural water. The measured capacities were used to develop Langmuir adsorption isotherms for each resin. 99Tc detection efficiencies were determined and up to 71.4 ± 2.6% was achieved with some resins. The results demonstrate that a low level detection limit for 99TcO4- in natural waters can be realized.

Mitchell Greenhalgh; Richard D. Tillotson

2012-07-01

297

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

298

UPTAKE OF METAL IONS BY A NEW CHELATING ION EXCHANGE RESIN. PART 3: PROTONATION CONSTANTS VIA POTENTIOMETRIC TITRATION AND SOLID STATE 31P NMR SPECTROSCOPY  

Microsoft Academic Search

A new chelating ion exchange resin which incorporates methylenediphosphonate, carboxylate, and sulfonate functional groups in a polystyrene-divinylbenzene matrix has been prepared. This resin exhibits exceptionally high affinity for polyvalent cations even from moderately acidic aqueous media. Metal ion coordination occurs primarily at the diphosphonate group with the secondary binding sites contributing to charge neutralization when necessary and possible, and to

K. L. Nash; P. G. Rickert; J. V. Muntean; S. D. Alexandratos

1994-01-01

299

Factorial experimental design for recovering heavy metals from sludge with ion-exchange resin.  

PubMed

Wastewaters containing heavy metals are usually treated by chemical precipitation method in Taiwan. This method can remove heavy metals form wastewaters efficiently, but the resultant heavy metal sludge is classified as hazardous solid waste and becomes another environmental problem. If we can remove heavy metals from sludge, it becomes non-hazardous waste and the treatment cost can be greatly reduced. This study aims at using ion-exchange resin to remove heavy metals such as copper, zinc, cadmium, and chromium from sludge generated by a PCB manufacturing plant. Factorial experimental design methodology was used to study the heavy metal removal efficiency. The total metal concentrations in the sludge, resin, and solution phases were measured respectively after 30 min reaction with varying leaching agents (citric acid and nitric acid); ion-exchange resins (Amberlite IRC-718 and IR-120), and temperatures (50 and 70 degrees C). The experimental results and statistical analysis show that a stronger leaching acid and a higher temperature both favor lower heavy metal residues in the sludge. Two-factors and even three-factor interaction effects on the heavy metal sorption in the resin phase are not negligible. The ion-exchange resin plays an important role in the sludge extraction or metal recovery. Empirical regression models were also obtained and used to predict the heavy metal profiles with satisfactory results. PMID:16843592

Lee, I Hsien; Kuan, Yu-Chung; Chern, Jia-Ming

2006-12-01

300

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

301

Advanced resin systems for graphite epoxy composites  

NASA Technical Reports Server (NTRS)

The value of resin/carbon fiber composites as lightweight structures for aircraft and other vehicle applications is dependent on many properties: environmental stability, strength, toughness, resistance to burning, smoke produced when burning, raw material costs, and complexity of processing. A number of woven carbon fiber and epoxy resin composites were made. The epoxy resin was commercially available tetraglycidylmethylene dianiline. In addition, composites were made using epoxy resin modified with amine and carboxyl terminated butadiene acrylonitrile copolymer. Strength and toughness in flexure as well as oxygen index flammability and NBS smoke chamber tests of the composites are reported.

Gilwee, W. J.; Jayarajan, A.

1980-01-01

302

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. PMID:5373675

Stamm, John M.; Engelhard, Warren E.; Parsons, James E.

1969-01-01

303

Tubular occlusion optimizes bonding of hydrophobic resins to dentin.  

PubMed

Although hydrophobic resins may be bonded to acid-etched dentin with an ethanol wet-bonding technique, the protocol is sensitive to moisture contamination when bonding is performed in deep dentin. This study tested the hypothesis that the use of oxalate or poly(glutamic) acid-modified, diluted ceramicrete (PADC) for dentinal tubule occlusion prevents fluid contamination and improves the bonding of an experimental hydrophobic adhesive to acid-etched, ethanol-dehydrated dentin. Mid-coronal and deep acid-etched moist dentin pre-treated with oxalate or PADC was dehydrated by ethanol wet-bonding and infiltrated with the experimental three-step etch-and-rinse hydrophobic adhesive under simulated pulpal pressure. Tensile bond strengths to deep dentin without pre-treatment were severely compromised. Conversely, oxalate and PADC pre-treatments reduced dentin permeability, prevented water contamination, and improved bond strengths. Minimal nanoleakage was identified within hybrid layers created in the oxalate- and PADC-pre-treated deep dentin. The use of tubular occluding agents optimized bonding of hydrophobic resins to dentin. PMID:17525351

Sadek, F T; Pashley, D H; Ferrari, M; Tay, F R

2007-06-01

304

Evaluating ion exchange resin efficiency and oxidative capacity for the separation of uranium(IV) and uranium(VI)  

PubMed Central

Background Previously described methods to separate dissolved U(IV) from dissolved U(VI) under acidic anoxic conditions prior to laboratory analysis were ineffective with materials currently available commercially. Three strong anion exchange resins were examined for their efficiency in separating, recovering, and preserving both redox states during separation. Results Under oxic conditions, recovery of U(VI) from three exchange resins (Bio-Rad AG® 1x8 Poly-Prep® prefilled columns, Bio-Rad AG® 1x8 powder, and Dowex® 1x8 powder) ranged from 72% to 100% depending on the dosed mass, eluent volume, and resin selected. Dowex® 1x8 resin was the only resin found to provide 100% recovery of U(VI) with fewer than 5 bed volumes of eluent. Under anoxic conditions, all three resins oxidized U(IV) in aqueous solutions with relatively low U(IV) concentrations (<3x10-6 M). Resin-induced oxidation was observed visually using a leuco dye, safranin-o. Oxidants associated with the resin were irreversibly reduced by the addition of Ti(III). After anoxic resin pre-treatment, a series of U(IV)/U(VI) mixtures at micro-molar levels were prepared and separated using the Dowex® 1x8 resin with 100% recovery of both U(IV) and U(VI) with no resin-induced changes in oxidation state. Conclusions Currently available anion exchange resins with apparently identical physical properties were found to have significantly different recoveries for hexavalent uranium at micro-molar concentrations. A novel qualitative technique was developed to visually assess oxidative capacities of anion exchange resins under acidic anoxic conditions. A protocol was developed for pre-treatment and use of currently available anion exchange resins to achieve quantitative separation of U(IV) and U(VI) in aqueous solutions with low U(IV) concentrations. This method can be applied to future work to quantitatively assess dissolved U(IV) and U(VI) concentrations in both laboratory and field samples. PMID:23363052

2013-01-01

305

75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan  

Federal Register 2010, 2011, 2012, 2013, 2014

...Polytetrafluoroethylene Resin From Italy and Japan AGENCY: United States International Trade...polytetrafluoroethylene resin from Italy and Japan...polytetrafluoroethylene resin from Italy and Japan would be likely to lead to...

2010-11-01

306

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...Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical...identified generically as modified phenolic resin (PMN P-01-561) is...

2010-07-01

307

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2009-04-01 true Phenolic resins in molded articles. 177.2410 Section...Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be...

2010-04-01

308

40 CFR 721.5905 - Modified phenolic resin (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified phenolic resin (generic). 721.5905 Section...Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical...identified generically as a modified phenolic resin (PMN P-01-441) is...

2010-07-01

309

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Aromatic aldehyde phenolic resin (generic). 721.5762 Section...721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical...generically as aromatic aldehyde phenolic resin (PMN P-01-573) is...

2010-07-01

310

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...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2010-04-01

311

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2012-07-01

312

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2014-07-01

313

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2011-07-01

314

40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

2013-07-01

315

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Root canal filling resin. 872.3820 Section 872... Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of...

2012-04-01

316

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Root canal filling resin. 872.3820 Section 872... Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of...

2014-04-01

317

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 872...Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device material,...

2011-04-01

318

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 872...Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a device material,...

2010-04-01

319

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2011 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...

2011-04-01

320

Adsorption and desorption of phenol on anion-exchange resin and activated carbon  

SciTech Connect

Adsorption and desorption of phenol on activated carbon and strong base anion-exchange resin were investigated in a fixed-bed column. Phenol was effectively adsorbed on both adsorbents. Experimental breakthrough curves were compared with values calculated on the assumption of surface diffusion controlling. Two methods of regeneration of adsorbents were carried out, that is, caustic desorption and acid desorption. Regeneration by sodium hydroxide or hydrochloric acid was effectively performed for the resin. On the other hand, regeneration of the activated carbon by sodium hydroxide was not performed completely. The adsorption capacity for activated carbon decreased gradually during the repetition process of adsorption and desorption, while the capacity for anion-exchange resin remained constant. 14 references, 9 figures, 1 table.

Goto, M.; Hayashi, N.; Goto, S.

1986-05-01

321

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

322

Biocompatibility of resin-modified filling materials.  

PubMed

Increasing numbers of resin-based dental restorations have been placed over the past decade. During this same period, the public interest in the local and especially systemic adverse effects caused by dental materials has increased significantly. It has been found that each resin-based material releases several components into the oral environment. In particular, the comonomer, triethyleneglycol di-methacrylate (TEGDMA), and the 'hydrophilic' monomer, 2-hydroxy-ethyl-methacrylate (HEMA), are leached out from various composite resins and 'adhesive' materials (e.g., resin-modified glass-ionomer cements [GICs] and dentin adhesives) in considerable amounts during the first 24 hours after polymerization. Numerous unbound resin components may leach into saliva during the initial phase after polymerization, and later, due to degradation or erosion of the resinous restoration. Those substances may be systemically distributed and could potentially cause adverse systemic effects in patients. In addition, absorption of organic substances from unpolymerized material, through unprotected skin, due to manual contact may pose a special risk for dental personnel. This is borne out by the increasing numbers of dental nurses, technicians, and dentists who present with allergic reactions to one or more resin components, like HEMA, glutaraldehyde, ethyleneglycol di-methacrylate (EGDMA), and dibenzoyl peroxide (DPO). However, it must be emphasized that, except for conventional composite resins, data reported on the release of substances from resin-based materials are scarce. There is very little reliable information with respect to the biological interactions between resin components and various tissues. Those interactions may be either protective, like absorption to dentin, or detrimental, e.g., inflammatory reactions of soft tissues. Microbial effects have also been observed which may contribute indirectly to caries and irritation of the pulp. Therefore, it is critical, both for our patients and for the profession, that the biological effects of resin-based filling materials be clarified in the near future. PMID:11021634

Geurtsen, W

2000-01-01

323

Degradation of aqueous carbon tetrachloride by nanoscale zerovalent copper on a cation resin.  

PubMed

Nanoscale zerovalent copper supported on a cation resin was successfully synthesized to enhance the removal of carbon tetrachloride (CCl(4)) from contaminated water. The use of the cation resin as a support prevents the reduction of surface area due to agglomeration of nanoscale zerovalent copper particles. Moreover, the cation resin recycles the copper ions resulting from the reaction between CCl(4) and Cu(0) by simultaneous ion exchange. The decline in the amount of CCl(4) in aqueous solution results from the combined effects of degradation by nanoscale zerovalent copper and sorption by the cation resin; thus the amount of CCl(4) both in aqueous solution and sorbed onto the resin were measured. The pseudo-first-order rate constant normalized by the surface-area and the mass concentration of nanoscale zerovalent copper (k(SA)) was 2.1+/-0.1 x 10(-2)lh(-1)m(-2), approximately twenty times that of commercial powdered zerovalent copper (0.04 mm). Due to the exchange between Cu(2+) and the strongly acidic ions (H(+) or Na(+)), the pH was between 3 and 4 in unbuffered solution and Cu(2+) at the concentration of less than 0.1 mg l(-1) was measured after the dechlorination reaction. In the above-ground application, resin as a support would facilitate the development of a process that could be designed for convenient emplacement and regeneration of porous reductive medium. PMID:15857641

Lin, Chin Jung; Lo, Shang-Lien; Liou, Ya Hsuan

2005-06-01

324

Polyimide Resins Resist Extreme Temperatures  

NASA Technical Reports Server (NTRS)

Spacecraft and aerospace engines share a common threat: high temperature. The temperatures experienced during atmospheric reentry can reach over 2,000 F, and the temperatures in rocket engines can reach well over 5,000 F. To combat the high temperatures in aerospace applications, Dr. Ruth Pater of Langley Research Center developed RP-46, a polyimide resin capable of withstanding the most brutal temperatures. The composite material can push the service temperature to the limits of organic materials. Designed as an environmentally friendly alternative to other high-temperature resins, the RP-46 polyimide resin system was awarded a 1992 "R&D 100" award, named a "2001 NASA Technology of the Year," and later, due to its success as a spinoff technology, "2004 NASA Commercial Invention of the Year." The technology s commercial success also led to its winning the Langley s "Paul F. Holloway Technology Transfer Award" as well as "Richard T. Whitcom Aerospace Technology Transfer Award" both for 2004. RP-46 is relatively inexpensive and it can be readily processed for use as an adhesive, composite, resin molding, coating, foam, or film. Its composite materials can be used in temperatures ranging from minus 150 F to 2,300 F. No other organic materials are known to be capable of such wide range and extreme high-temperature applications. In addition to answering the call for environmentally conscious high-temperature materials, RP-46 provides a slew of additional advantages: It is extremely lightweight (less than half the weight of aluminum), chemical and moisture resistant, strong, and flexible. Pater also developed a similar technology, RP-50, using many of the same methods she used with RP-46, and very similar in composition to RP-46 in terms of its thermal capacity and chemical construction, but it has different applications, as this material is a coating as opposed to a buildable composite. A NASA license for use of this material outside of the Space Agency as well as additional government-funded testing proved that RP-46 is even more exceptional than originally thought.

2009-01-01

325

Phosphorus-containing imide resins  

NASA Technical Reports Server (NTRS)

Cured polymers of bis and tris-imides derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydride or its derivatives, and addition polymers of such imides, including a variant in which a monoimide is condensed with a dianhydride and the product is treated with a further quantity of maleic anhydride prior to curing are disclosed and claimed. Such polymers are flame resistant. Also disclosed are an improved method of producing tris(m-aminophenyl) phosphine oxides from the nitro analogues by reduction with hydrazine hydrate using palladized charcoal or Raney nickel as the catalyst and fiber reinforced cured resin composites.

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

1985-01-01

326

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2012 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2012-04-01

327

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2013 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2013-04-01

328

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2011 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2011-04-01

329

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2014 CFR

...dimethylamine and oxidized with hydrogen peroxide whereby the resin contains not...calcium, carbonate, chloride, hydrogen, hydroxyl, magnesium...cation-exchange resins in the hydrogen form identified in...

2014-04-01

330

Extraction and separation of In(III), Ga(III) and Zn(II) from sulfate solution using extraction resin  

Microsoft Academic Search

The separation of In(III), Ga(III) and Zn(II) from sulfate solution has been studied using an extraction resin containing 2-ethylhexyl phosphoric acid mono(2-ethylhexyl) ester (P507 extraction resin). The effect of pH on the extraction of each metal was determined. Extraction isotherms were then constructed at selected pH. Results show that In(III) is first extracted from aqueous solutions at pH 2.0 using

J. S. Liu; H. Chen; X. Y. Chen; Z. L. Guo; Y. C. Hu; C. P. Liu; Y. Z. Sun

2006-01-01

331

The use of bimodal blends of vinyl ester monomers to improve resin processing and toughen polymer properties  

Microsoft Academic Search

Vinyl ester (VE) monomers with bimodal molecular weight distributions were prepared by reacting methacrylic acid with blends of monodisperse epoxy resins ranging in molecular weight from 350–7000g\\/mol. Monodisperse vinyl ester monomers were prepared from epoxy resins of a single molecular weight. The extent of vinyl ester formation was found to be near complete and side reactions, such as etherification, did

John J. La Scala; Joshua A. Orlicki; Cherise Winston; E. Jason Robinette; James M. Sands; Giuseppe R. Palmese

2005-01-01

332

The effect of additional etching and curing mechanism of composite resin on the dentin bond strength  

PubMed Central

PURPOSE The aim of this study was to evaluate the effects of additional acid etching and curing mechanism (light-curing or self-curing) of a composite resin on the dentin bond strength and compatibility of one-step self-etching adhesives. MATERIALS AND METHODS Sixteen human permanent molars were randomly divided into eight groups according to the adhesives used (All-Bond Universal: ABU, Clearfil S3 Bond: CS3), additional acid etching (additional acid etching performed: EO, no additional acid etching performed: EX), and composite resins (Filtek Z-250: Z250, Clearfil FII New Bond: CFNB). Group 1: ABU-EO-Z250, Group 2: ABU-EO-CFNB, Group 3: ABU-EX-Z250, Group 4: ABU-EX-CFNB, Group 5: CS3-EO-Z250, Group 6: CS3-EO-CFNB, Group 7: CS3-EX-Z250, Group 8: CS3-EX-CFNB. After bonding procedures, composite resins were built up on dentin surfaces. After 24-hour water storage, the teeth were sectioned to make 10 specimens for each group. The microtensile bond strength test was performed using a microtensile testing machine. The failure mode of the fractured specimens was examined by means of an optical microscope at ×20 magnification. The data was analyzed using a one-way ANOVA and Scheffe's post-hoc test (?=.05). RESULTS Additional etching groups showed significantly higher values than the no additional etching group when using All-Bond Universal. The light-cured composite resin groups showed significantly higher values than the self-cured composite resin groups in the Clearfil S3 Bond. CONCLUSION The additional acid etching is beneficial for the dentin bond strength when using low acidic one-step self-etch adhesives, and low acidic one-step self-etch adhesives are compatible with self-cured composite resin. The acidity of the one-step self-etch adhesives is an influencing factor in terms of the dentin bonding strength and incompatibility with a self-cured composite resin. PMID:24353889

Lee, In-Su; Son, Sung-Ae; Hur, Bock; Kwon, Yong-Hoon

2013-01-01

333

Surface preparations for metal frameworks of composite resin veneered prostheses made with an adhesive opaque resin.  

PubMed

Bond strengths of a laboratory developed light-cured composite resin to dental casting alloys were evaluated with a new adhesive opaque resin. The metal specimens were type III gold, nickel-chromium, and cobalt-chromium alloys, while the surface treatments for bonding were heating, Sn plating, and ion coating. The cast metal specimens were "particle blasted" with aluminum oxide and were surface treated. Adhesive 4-META/MMA-TBB opaque resin was applied and a light-cured composite resin was placed over the opaque layer. The prepared specimens were thermocycled in water and shear bond strengths were recorded. The light-cured composite resin was bonded strongly to heated or Sn-plated type III alloy with 4-META/MMA-TBB opaque resin. Copper ion coating in a sputter coater was effective for all three alloys, with only slightly diminished bond strengths. These methods were satisfactory for making composite resin veneered prostheses. PMID:1941662

Matsumura, H; Kawahara, M; Tanaka, T; Atsuta, M

1991-07-01

334

Modified resins for solid-phase extraction  

DOEpatents

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Fritz, James S. (Ames, IA); Sun, Jeffrey J. (Ames, IA)

1991-12-10

335

Modified resins for solid-phase extraction  

DOEpatents

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Fritz, James S. (Ames, IA); Sun, Jeffrey J. (Ames, IA)

1993-07-27

336

IMPROVEMENTS IN EPOXY RESIN EMBEDDING METHODS  

Microsoft Academic Search

Epoxy embedding methods of Glauert and Kushida have been modified so as to yield rapid, reproducible, and convenient embedding methods for electron microscopy. The sections are robust and tissue damage is less than with methacrylate embedding. It has become apparent that there is considerable advantage in using epoxy resins in embedding tissues for electron microscopy. Compared to methacrylates, epoxy resins

JOHN H. LUFT

337

Volumetric polymerization shrinkage of contemporary composite resins.  

PubMed

The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill Magic, Alert, and Solitaire) to determine whether there are differences among these materials. The tests were conducted with precision of 0.1 mg. The volumetric shrinkage was measured by hydrostatic weighing before and after polymerization and calculated by known mathematical equations. One-way ANOVA (á = 0.05) was used to determine statistically significant differences in volumetric shrinkage among the tested composite resins. Suprafill (1.87+/-0.01) and Definite (1.89+/-0.01) shrank significantly less than the other composite resins. SureFil (2.01+/-0.06), Filtek Z250 (1.99+/-0.03), and Fill Magic (2.02+/-0.02) presented intermediate levels of polymerization shrinkage. Alert and Solitaire presented the highest degree of polymerization shrinkage. Knowing the polymerization shrinkage rates of the commercially available composite resins, the dentist would be able to choose between using composite resins with lower polymerization shrinkage rates or adopting technical or operational procedures to minimize the adverse effects deriving from resin contraction during light-activation. PMID:19089177

Nagem Filho, Halim; Nagem, Haline Drumond; Francisconi, Paulo Afonso Silveira; Franco, Eduardo Batista; Mondelli, Rafael Francisco Lia; Coutinho, Kennedy Queiroz

2007-10-01

338

Silicone modified resins for graphite fiber laminates  

NASA Technical Reports Server (NTRS)

Six silicone modified resins were selected for evaluation in unidirectional filament wound graphite laminates. Neat samples of these resins had 1,000 C char residues of 6-63%. The highest flexural values measured for the laminates were a strength of 1,220 MPa and a modulus of 105 GPa. The highest interlaminar shear strength was 72 MPa.

Frost, L. W.; Bower, G. M.

1980-01-01

339

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2013 CFR

...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

2013-04-01

340

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2012 CFR

...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

2012-04-01

341

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2010 CFR

...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

2010-04-01

342

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2011 CFR

...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

2011-04-01

343

21 CFR 177.1550 - Perfluorocarbon resins.  

Code of Federal Regulations, 2014 CFR

...characteristic infrared spectra. (2) Melt-viscosity. (i) The per-fluoro-carbon resins...1) of this section shall have a melt viscosity of not less than 104 poises at 380...ibr_locations.html. The melt viscosity of the perfluorocarbon resins...

2014-04-01

344

TALONTM Resins I. List of Components  

E-print Network

) 5 2-ml Disposable Gravity Columns 1 10-ml Disposable Gravity Column · TALONTM Buffer Kit (#K1252 Imidazole, pH 7) · TALONTM 2-ml Disposable Gravity Columns (#8903-1) TALONTMResinProtocol 37BD Biosciences to TALON Resins, which decreases resin specific capacity and the final purity of your target protein. You

Lebendiker, Mario

345

Therapeutic effects of novel resin bonding systems containing bioactive glasses on mineral-depleted areas within the bonded-dentine interface.  

PubMed

This study aimed in evaluating the effects of two experimental resin bonding systems containing conventional Bioglass 45S5 (BAG) or Zinc-polycarboxylated bioactive glass (BAG-Zn) micro-fillers on the resin-bonded dentine interface after storage in a simulated body fluid solution (SBFS). Three resin bonding systems were formulated: Resin-A: (BAG containing); Resin-B; (BAG-Zn containing); Resin-C (no filler). The ability of the experimental resins to evoke apatite formation was evaluated using confocal Raman spectroscopy. Acid-etched dentine specimens were bonded, and prepared for AFM/nano-indentation analysis in a fully-hydrated status to evaluate the modulus of elasticity (Ei) and hardness (Hi) across the interface at different SBFS storage periods. Further resin-dentine specimens were tested for microtensile bond strength after 24 h or 3 months of SBFS storage. SEM examination was performed after de-bonding and confocal laser microscopy was used to evaluate the ultramorphology of the interfaces and micropermeability. The resin A and B showed a consistent presence of apatite (967 cm(-1)), reduced micropermeability within the resin-dentine interface and a significant increase of the Ei and Hi along the bonded-dentine interface after prolonged SBFS storage. Bond strength values were affected by the resin system (P < 0.0001) and by storage time (P < 0.0001) both after 24 h and 3 months of SBFS storage. In conclusion, resin bonding systems containing bioactive fillers may a have therapeutic effect on the nano-mechanical properties and sealing ability of mineral-depleted resin-dentine interface. PMID:22466816

Sauro, Salvatore; Osorio, Raquel; Watson, Timothy F; Toledano, Manuel

2012-06-01

346

Characterization of an anti-tuberculosis resin glycoside from the prairie medicinal plant Ipomoea leptophylla.  

PubMed

The organic soluble extract from the leaves of the native North American prairie plant Ipomoea leptophylla (big root morning glory) showed in vitro activity against M. tuberculosis. Bioassay-guided fractionation of this extract resulted in the identification of two new resin glycosides (6, 7). Base-catalyzed hydrolysis of these glycosides gave operculinic acid (1) as the glycosidic acid component as well as trans-cinnamic acid, propanoic acid, and lauric acid. The complete structure elucidation was accomplished through derivatization, 1D and 2D NMR spectroscopy (TOCSY, ROESY, HSQC, HMBC), and MS/MS experiments on 6 and 7 as well as the permethylated derivative 8. PMID:14640518

Barnes, Curtis C; Smalley, Mary K; Manfredi, Kirk P; Kindscher, Kelly; Loring, Hillary; Sheeley, Douglas M

2003-11-01

347

Reduction of polyester resin shrinkage by means of epoxy resin—II. Epoxy resin modified with acrylamide and N-hydroxymethyloloacrylamide  

NASA Astrophysics Data System (ADS)

The possibility was investigated of reducing the shrinkage of unsaturated polyester resin taking place in radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified by introducing unsaturated bonds via acrylamide and N-hydroxymethyloloacrylamide. A composition of 90% unsaturated polyester resin and 10% acrylamide-modified epoxy resin, filled with silica (1:1.5), showed a volume shrinkage below 2%.

Pietrzak, M.; Brzostowski, A.

348

Synthesis and characterization of amphoteric resins and its use for treatment of radioactive liquid waste  

SciTech Connect

Amphoteric resins such as poly (acrylamide-acrylic acid-diallylamine-hydrochloride) {open_quotes}P(AH-AA-DAA){sup +}Cl{close_quotes} and poly (acrylamide-acrylic acid-dially-ethylamine-hydrochloride) {open_quotes}P(AM-AA-DAEA){sup +} Cl{close_quotes} were prepared by gamma radiation-induced polymerization of acrylic acid {open_quotes}AA{close_quotes} in the presence of poly(amidoamines) such as poly(acryl-amide-diallyamine-hydrochloride) {open_quotes}P(AM- DAAH){sup +}Cl{close_quotes} and poly(acrylamide-dially-ethylamine-hydrochloride){close_quotes}P(AM-DAEAH){sup +} Cl{sup -}{close_quotes} it as template polymers using a template polymerization technique. Spectroscopic studies showed that resins contain both amide- and carboxylic groups, and the peak of {r_angle}NH of amine salts at (3000-2700 cm{sup {minus}1}) and (2700-2500 cm{sup {minus}1}) is disappeared. This indicates that the addition of acrylic acid monomer on ammonium groups. These ammonium groups in template polymers are converted into acrylic acid chain ends in the obtained resins accordingly, the probability of the polymer degradation of decreases may be attributed to the high radiation stability of these chain ends of acrylic acid units. The capacities of the obtained resins increase by increasing the absorbed doses of about {approximately}20 kGy, but at high doses the capacities decrease. On increasing the amines ratio in template polymers the capacities of resins for cation decreased but increased for anions. The capacities of the product materials to some heavy metal ions decrease with increasing the hydrogen ion concentrations and the selectivity is decreased in the order Cu{sup 2+} > Co{sup 2+} > Cs{sup +}.

Siyam, T.; El-Naggar, I.M.; Aly, H.F. [Atomic Energy Authority, Cairo (Egypt)

1996-12-31

349

Release and toxicity of dental resin composite  

PubMed Central

Dental resin composite that are tooth-colored materials have been considered as possible substitutes to mercury-containing silver amalgam filling. Despite the fact that dental resin composites have improved their physico-chemical properties, the concern for its intrinsic toxicity remains high. Some components of restorative composite resins are released in the oral environment initially during polymerization reaction and later due to degradation of the material. In vitro and in vivo studies have clearly identified that these components of restorative composite resins are toxic. But there is a large gap between the results published by research laboratories and clinical reports. The objective of this manuscript was to review the literature on release phenomenon as well as in vitro and in vivo toxicity of dental resin composite. Interpretation made from the recent data was also outlined. PMID:23293458

Gupta, Saurabh K.; Saxena, Payal; Pant, Vandana A.; Pant, Aditya B.

2012-01-01

350

Zoledronate and ion-releasing resins impair dentin collagen degradation.  

PubMed

This study analyzed the amounts of solubilized telopeptides cross-linked carboxyterminal telopeptide of type I collagen (ICTP) and C-terminal crosslinked telopeptide of type I collagen (CTX) derived from matrix-metalloproteinases (MMPs) and cysteine cathepsins (CTPs) subsequent to application of a filler-free (Res.A) or an ion-releasing resin (Res.B) to ethylenediaminetetraacetic acid (EDTA)-demineralized dentin with or without zoledronate-containing primer (Zol-primer) pre-treatment. The chemical modification induced following treatments and artificial saliva (AS) storage was also analyzed through attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Totally EDTA-demineralized specimens were infiltrated with Res.A or Res.B with or without Zol-primer pre-treatment, light-cured, and immersed in AS for up to 4 wk. ICTP release was reduced following infiltration with Res.B and further reduced when Res.B was used with Zol-primer; remarkable phosphate mineral uptake was attained after AS storage. CTX release was increased in Res.A- and Res.B-treated dentin. However, when Zol-primer was used with Res.A, the CTX release fell significantly compared to the other tested resin-infiltration methods. In conclusion, zoledronate offers an additional inhibitory effect to the ion-releasing resins in MMP-mediated collagen degradation. However, Zol-primer induces a modest reduction in CTX release only when used with resin-based systems containing no ion-releasing fillers. PMID:25074494

Tezvergil-Mutluay, A; Seseogullari-Dirihan, R; Feitosa, V P; Tay, F R; Watson, T F; Pashley, D H; Sauro, S

2014-10-01

351

POLYAMIDE-EPICHLOROHYDRIN RESINS FOR UNION DYEING WOOL/COTTON BLENDED FABRICS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cationic amine polyamide-epichlorohydrin (PAE) resins were applied as pretreatments to all-wool, all-cotton, and blends of wool/cotton for subsequent one-step union dyeing with acid dyes following the conventional wool dyeing process. Compared to cationic biguanide and dimethyloldihydroxyethyleneur...

352

Mechanical Properties of Surface-Charged Poly(Methyl Methacrylate) as Denture Resins  

PubMed Central

The aim of this study was to examine the mechanical properties of a new surface-modified denture resin for its suitability as denture base material. This experimental resin is made by copolymerization of methacrylic acid (MA) to poly(methyl methacrylate) (PMMA) to produce a negative charge. Four experimental groups consisted of Orthodontic Dental Resin (DENTSPLY Caulk) as a control and three groups of modified PMMA (mPMMA) produced at differing ratios of methacrylic acid (5 : 95, 10 : 90, and 20 : 80 MA : MMA). A 3-point flexural test using the Instron Universal Testing Machine (Instron Corp.) measured force-deflection curves and a complete stress versus strain history to calculate the transverse strength, transverse deflection, flexural strength, and modulus of elasticity. Analysis of Variance and Scheffe Post-test were performed on the data. Resins with increased methacrylic acid content exhibited lower strength values for the measured physical properties. The most significant decrease occurred as the methacrylic acid content was increased to 20% mPMMA. No significant differences at P < .05 were found in all parameters tested between the Control and 5% mPMMA. PMID:20339462

Park, Sang E.; Chao, Maggie; Raj, P. A.

2009-01-01

353

Adsorption and desorption of phenol on anion-exchange resin and activated carbon  

Microsoft Academic Search

Adsorption and desorption of phenol on activated carbon and strong base anion-exchange resin were investigated in a fixed-bed column. Phenol was effectively adsorbed on both adsorbents. Experimental breakthrough curves were compared with values calculated on the assumption of surface diffusion controlling. Two methods of regeneration of adsorbents were carried out, that is, caustic desorption and acid desorption. Regeneration by sodium

Motonobu. Goto; Norio. Hayashi; Shigeo. Goto

1986-01-01

354

LAB STUDY ON REGENERATION OF SPENT DOWEX 21K 16-20 MESH ION EXCHANGE RESIN  

SciTech Connect

Currently the effort to remove chromate from groundwater in the 100K and 100H Areas uses DOWEX 21K 16-20. This report addresses the procedure and results of a laboratory study for regeneration of the spent resin by sodium hydroxide, sulfuric acid, or sodium sulfate to determine if onsite regeneration by the Effluent Treatment Facility is a feasible option.

DUNCAN, J.B.

2007-01-24

355

Boron Removal by Anion Exchangers Impregnated with Citric and Tartaric Acids  

Microsoft Academic Search

The separation of boron compounds, boric acid and borax, with anion-exchange resins, before and after impregnation with citric and tartaric acids, has been studied. Three different commercially available anion exchangers were selected for this study. The results indicate that ion-exchanging on the examined resins is not quite effective for the removal of boron from boric acid and borax water solution.

M. Dj. Risti?; Lj. V. Rajakovi?

1996-01-01

356

Antimicrobial Activities of Amphiphilic Peptides Covalently Bonded to a Water-Insoluble Resin  

Microsoft Academic Search

A series of polymer-bound antimicrobial peptides was prepared, and the peptides were tested for their antimicrobial activities. The immobilized peptides were prepared by a strategy that used solid-phase peptide synthesis that linked the carboxy-terminal amino acid with an ethylenediamine-modified polyamide resin (PepsynK). The acid-stable, permanent amide bond between the support and the nascent peptide renders the peptide resistant to cleavage

SHARON L. HAYNIE; GRACE A. CRUM; ANDBRUCE A. DOELE

1995-01-01

357

Resin/graphite fiber composites  

NASA Technical Reports Server (NTRS)

Processing techniques were developed for the fabrication of both polyphenylquinoxaline and polyimide composites by the in situ polymerization of monomeric reactants directly on the graphite reinforcing fibers, rather than using previously prepared prepolymer varnishes. Void-free polyphenylquinoxaline composites were fabricated and evaluated for room and elevated flexure and shear properties. The technology of the polyimide system was advanced to the point where the material is ready for commercial exploitation. A reproducible processing cycle free of operator judgment factors was developed for fabrication of void-free composites exhibiting excellent mechanical properties and a long time isothermal life in the range of 288 C to 316 C. The effects of monomer reactant stoichiometry and process modification on resin flow were investigated. Demonstration of the utility and quality of this polyimide system was provided through the successful fabrication and evaluation of four complex high tip speed fan blades.

Cavano, P. J.

1974-01-01

358

Investigation of gamma induced degradation of Amberlite 200 cation resin by mass spectrometer and liquid chromatograph  

E-print Network

exchange capacity, salt-splitting exchange capacity and solids content changed with accumulated dose losing 14, 19, and 7 percent, respectively, after 5XIO Rads. 8 ACKNOWLEDGEMENTS i wish to express my appreciation to Dr. James B. Smathers, who advi... effluent pH versus accumulated dose. . 10 4a. Irradiated resin effluent at 192 hours (1. 655XIO 8 Rads). 12 4b. Known sulfuric acid. 13 INTRODUCTION Eon exchange resins are used in demineralizers for cleanup and maintaining the purity of primary water...

Freitag, Albert Antonio

1977-01-01

359

Tc-99 Ion Exchange Resin Testing  

SciTech Connect

Pacific Northwest National Laboratory was contracted by CHPRC to evaluate the release of 99Tc from spent resin used to treat water from well 299-W15-765 and stored for several years. The key questions to be answered are: 1) does 99Tc readily release from the spent ion exchange resin after being in storage for several years; 2) if hot water stripping is used to remove the co-contaminant carbon tetrachloride, will 99Tc that has been sequestered by the resin be released; and 3) can spent resin be encapsulated into a cementitious waste form; if so, how much 99Tc would be released from the weathering of the monolith waste form? The results from the long term stability leach test results confirm that the resin is not releasing a significant amount of the sequestered 99Tc, evident by the less than 0.02% of the total 99Tc loaded being identified in the solution. Furthermore, it is possible that the measured 99Tc concentration is the result of 99Tc contained in the pore spaces of the resin. In addition to these results, analyses conducted to examine the impact of hot water on the release of 99Tc suggest that only a small percentage of the total is being released. This suggest that hot water stripping to remove carbon tetrachloride will not have a significant affect on the resin’s ability to hold-on to sequestered 99Tc. Finally, encapsulation of spent resin in a cementitious material may be a viable disposal option, but additional tests are needed to examine the extent of physical degradation caused by moisture loss and the effect this degradation process can have on the release of 99Tc.

Valenta, Michelle M.; Parker, Kent E.; Pierce, Eric M.

2010-08-01

360

Characterizing Delamination Resistance of Toughened Resin Composites  

NASA Technical Reports Server (NTRS)

The delamination resistance of toughened resin composites was studied. Both the edge delamination test (EDT) and the double-cantilever-beam (DCB) test provided a useful ranking of improvements in delamination resistance between brittle and tough resin composites. Several layups were designed for the edge delamination test to cover a wide range of mixed-mode conditions. The DCB and the various layups of the EDT were then used to characterize the interlaminar fracture behavior of brittle and toughened resin composites subjected to both static and cyclic loading.

Obrien, T. K.

1984-01-01

361

Improved microbial-check-valve resins  

NASA Technical Reports Server (NTRS)

Improved microbial-check-valve resins have been tested for their microbicidal effectiveness and long-term stability. Resins give more-stable iodine concentrations than previous preparations and do not impart objectionable odor or taste to treated water. Microbial check valve is small cylindrical device, packed with iodide-saturated resin, that is installed in water line where contamination by micro-organisms is to be prevented. Prototype microbial check valve was tested for stability and performance under harsh environmental conditions. Effectiveness was 100 percent at 35 deg, 70 deg, and 160 deg F (2 deg, 21 deg, and 71 deg C).

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

1980-01-01

362

Method for selective plugging using resin emulsions  

SciTech Connect

Methods and compositions are provided for selectively plugging the water-rich strata of subterranean formations, including injection into the formation of a water-insoluble, oil-soluble resin emulsion. A series of chemical reactions is initiated insitu such that the emulsion demulsifies, resulting in the coalescence of resin droplets. The coalesced water-insoluble, oil-soluble resin droplets are effective to selectively plug the water-rich strata over a relatively long distance and over a relatively long period of time.

Friedman, R.H.

1982-10-05

363

Chemical Characterization of Phenol/Formaldehyde Resins  

NASA Technical Reports Server (NTRS)

Report discusses tests of commercial phenol/formaldehyde resins to establish relationships among composition before use, behavior during curing, and strength after curing. Resin used in carbon/carbon laminates. In curing process, two molecules of phenol joined together in sequence of reactions involving molecule of formaldehyde. Last step of sequence, molecule of water released. Sequence repeats until one of ingredients used up, leaving solidified thermoset plastic. Issues to be resolved: number and relative abundances of ingredients, presence of certain chemical groups, heat-producing ability of resin, and range of molecular weights present.

Brayden, T. H.

1986-01-01

364

SEM and elemental analysis of composite resins  

SciTech Connect

Twenty-four chemically cured, 21 light-cured anterior, three light-cured anterior/posterior, and 18 light-cured posterior composite resins were examined using scanning electron microscopy, and the elemental composition of their filler particles was analyzed with an energy dispersive electron probe microanalyzer. According to the results obtained, the composite resins were divided into five groups (traditional, microfilled type, submicrofilled type, hybrid type, and semihybrid), with two additional hypothetical categories (microfilled and hybrid). Characteristics of each type were described with clinical indications for selective guidance of respective composite resins for clinical use.

Hosoda, H.; Yamada, T.; Inokoshi, S. (Tokyo Medical and Dental Univ., (Japan))

1990-12-01

365

Cobalt Ions Improve the Strength of Epoxy Resins  

NASA Technical Reports Server (NTRS)

Technique developed for improving mechanical strength of epoxy resins by adding cobalt ions in form of tris(acetylacetonato)cobalt (III) complex. Solid cast disks prepared from cobalt ion-containing epoxy resins tested for flexural strength and stiffness. Incorporation of cobalt ions into epoxies increased flexural strength of resins by 10 to 95 percent. Suitable resins for this technique include any liquid or solid TGMDA resins. Improved epoxy formulation proves useful as composite matrix resin, adhesive, or casting resin for applications on commercial and advanced aircraft.

Stoakley, D. M.; St. Clair, A. K.

1986-01-01

366

A medicated polycarboxylate cement to prevent complications in composite resin therapy  

SciTech Connect

Preparative treatment is the preferred method to protect the dentin and pulp from complications in composite resin therapy. This study investigated the in vivo effects of the polycarboxylate cement containing zinc fluoride and tannic acid in composite resin restorations. Scanning electron micrographs established that the composite resin failed to contact the axial wall. The gaps varied from 10 to 60 microns. However, this polycarboxylate cement was shown to provide excellent adaptation to dentin when used as a base and its chemical adhesion allowed it to make close contact with the unetched dentin. The newly developed electron probe x-ray microanalyzer revealed that the in vivo penetration of fluoride and zinc occurred through the dentinal tubules. When this polycarboxylate cement was used, the orifices of dentinal tubules were partially occluded, possibly with the smear layer fixed by tannic acid. In addition, by releasing the components, this polycarboxylate cement adds acid resistance to dentin and increases the resistance of dentin collagen to proteolytic enzymes. As such this polycarboxylate cement offers advantages as a base to composite resin therapy.

Okamoto, Y.; Shintani, H.; Yamaki, M. (Hiroshima Univ., School of Dentistry (Japan))

1990-01-01

367

Gastroprotective effect of the Mapuche crude drug Araucaria araucana resin and its main constituents.  

PubMed

The resin from the tree Araucaria araucana (Araucariaceae) has been used since pre-columbian times by the Mapuche amerindians to treat ulcers. The gastroprotective effect of the resin was assessed in the ethanol-HCl-induced gastric ulcer in mice showing a dose-dependent gastroprotective activity at 100, 200 and 300 mg/kg per os. The main three diterpene constituents of the resin, namely imbricatolic acid, 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid were isolated and evaluated for gastroprotective effect at doses of 50, 100 and 200 mg/kg. A dose-related gastroprotective effect with highly significant activity (P<0.01) was observed at doses up to 200 mg/kg. At 100 mg/kg, the highest gastroprotective activity was provided by 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of the main diterpenes as well as lansoprazole was studied towards human lung fibroblasts (MRC-5) and determined by the MTT reduction assay. A concentration-dependent cell viability inhibition was found with IC50 values ranging from 125 up to 290 microM. Our results support the traditional use of the Araucaria araucana resin by the Mapuche culture. PMID:15985351

Schmeda-Hirschmann, Guillermo; Astudillo, Luis; Rodríguez, Jaime; Theoduloz, Cristina; Yáñez, Tania

2005-10-01

368

Hydraulic Permeability of Resorcinol-Formaldehyde Resin  

SciTech Connect

An ion exchange process using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the Hanford Site, using large scale columns as part of the Waste Treatment Plant (WTP). The RF resin is also being evaluated for use in the proposed small column ion exchange (SCIX) system, which is an alternative treatment option at Hanford and at the Savannah River Site (SRS). A recirculating test loop with a small ion exchange column was used to measure the effect of oxygen uptake and radiation exposure on the permeability of a packed bed of the RF resin. The lab-scale column was designed to be prototypic of the proposed Hanford columns at the WTP. Although the test equipment was designed to model the Hanford ion exchange columns, the data on changes in the hydraulic permeability of the resin will also be valuable for determining potential pressure drops through the proposed SCIX system. The superficial fluid velocity in the lab-scale test (3.4-5.7 cm/s) was much higher than is planned for the full-scale Hanford columns to generate the maximum pressure drop expected in those columns (9.7 psig). The frictional drag from this high velocity produced forces on the resin in the lab-scale tests that matched the design basis of the full-scale Hanford column. Any changes in the resin caused by the radiation exposure and oxygen uptake were monitored by measuring the pressure drop through the lab-scale column and the physical properties of the resin. Three hydraulic test runs were completed, the first using fresh RF resin at 25 C, the second using irradiated resin at 25 C, and the third using irradiated resin at 45 C. A Hanford AP-101 simulant solution was recirculated through a test column containing 500 mL of Na-form RF resin. Known amounts of oxygen were introduced into the primary recirculation loop by saturating measured volumes of the simulant solution with oxygen and reintroducing the oxygenated simulant into the feed tank. The dissolved oxygen (DO) concentration of the recirculating simulant was monitored, and the amount of oxygen that reacted with the resin was determined from the change in the DO concentration of the recirculating simulant solution. Prior to hydraulic testing the resin for runs 2 and 3 was covered with the simulant solution and irradiated in a spent fuel element at the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR). Both batches of resin were irradiated to a total gamma dose of 177 Mrad, but the resin for run 2 reached a maximum temperature during irradiation of 51 C, while the resin for run 3 reached a temperature of 38 C. The different temperatures were the result of the operating status of HFIR at the time of the irradiation and were not part of the test plan; however, the results clearly show the impact of the higher-temperature exposure during irradiation. The flow rate and pressure drop data from the test loop runs show that irradiating the RF resin reduces both the void fraction and the permeability of the resin bed. The mechanism for the reduction in permeability is not clear because irradiation increases the particle size of the resin beads and makes them deform less under pressure. Microscopic examination of the resin beads shows that they are all smooth regular spheres and that irradiation or oxygen uptake did not change the shape of the beads. The resin reacts rapidly with DO in the simulant solution, and the reaction with oxygen reduces the permeability of a bed of new resin by about 10% but has less impact on the permeability of irradiated resin. Irradiation increases the toughness of the resin beads, probably by initiating cross-linking reactions in them. Oxygen uptake reduces the crush strength of both new and irradiated resin; however, the pressures that caused the beads to crush are much higher than would be expected during the operation of an ion exchange column. There was no visible evidence of broken beads in any of the resin samples taken from the test loop. Reaction with oxygen red

Taylor, Paul Allen [ORNL

2010-01-01

369

Method for regenerating magnetic polyamine-epichlorohydrin resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

1997-07-29

370

Method for regenerating magnetic polyamine-epichlorohydrin resin  

DOEpatents

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

Kochen, R.L.; Navratil, J.D.

1997-07-29

371

Phenoxy resins containing pendent ethynyl groups and cured resins obtained therefrom  

NASA Technical Reports Server (NTRS)

Phenoxy resins containing pendent ethynyl groups, the process for preparing the same, and the cured resin products obtained therefrom are disclosed. Upon the application of heat, the ethynyl groups react to provide branching and crosslinking with the cure temperature being lowered by using a catalyst if desired but not required. The cured phenoxy resins containing pendent ethynyl groups have improved solvent resistance and higher use temperature than linear uncrosslinked phenoxy resins and are applicable for use as coatings, films, adhesives, composited matrices and molding compounds.

Hergenrother, P. M. (inventor)

1985-01-01

372

Factors influencing the rate of gas evolution from epoxide resins during irradiation  

SciTech Connect

This work examined the influence of resin and hardener structure, together with the associated processing variables, on the rate of radiation induced gas evolution. Glycidyl ether and glycidyl amine resins are considered, together with aromatic amine and acid anhydride hardeners and such processing variables as cure schedule, accelerator content and amount of anhydride hardener. The effect of specimen geometry on the total gas evolved for unit radiation dose is also examined. A range of {open_quote}radical scavengers{close_quote} has been investigated, in relation to the structure of the resin and hardener components, to investigate the possibility of reducing the total radiolytic gas evolution. A nuclear reactor was used for the irradiation studies - and a system of dosimetry based on the well characterized gas evolution from polyethylene provided comprehensive information relating to dose distribution within the reactor.

Evans, D. [Rutherford Appleton Lab., Oxon (United Kingdom); Reed, R.P. [Cryogenic Materials Inc., Boulder, CO (United States)

1997-06-01

373

Improved recovery and purification of plutonium at Los Alamos using macroporous anion exchange resin  

SciTech Connect

For almost 30 years, Los Alamos National Laboratory has used anion exchange in nitric acid as the major aqueous process or the recovery and purification of plutonium. One of the few disadvantages of this system is the particularly slow rate at which the anionic nitrato complex of Pu(IV) equilibrates with the resin. The Nuclear Materials Process Technology Group at Los Alamos recently completed an ion exchange development program that focused on improving the slow sorption kinetics that limits this process. A comprehensive investigation of modern anion exchange resins identified porosity and bead size as the properties that most influence plutonium sorption kinetics. Our study found that small beads of macroporous resin produced a dramatic increase in plutonium process efficiency. The Rocky Flats Plant has already adopted this improved ion exchange technology, and it currently is being evaluated for use in other DOE plutonium-processing facilities.

Marsh, S.F.; Mann, M.J. (ed.)

1987-05-01

374

Accurate determination of ?¹Ca concentrations in spent resins from the nuclear industry by accelerator mass spectrometry.  

PubMed

The radiological characterisation of nuclear waste is essential for managing storage sites. Determining the concentration of Long-Lived RadioNuclides (LLRN) is fundamental for their long-term management. This paper focuses on the measurement of low (41)Ca concentrations in ions exchange resins used for primary fluid purification in Pressurised Water Reactors (PWR). (41)Ca concentrations were successfully measured by Accelerator Mass Spectrometry (AMS) after the acid digestion of resin samples, followed by radioactive decontamination and isobaric suppression through successive hydroxide, carbonate, nitrate and final CaF2 precipitations. Measured (41)Ca concentrations ranged from 0.02 to 0.03 ng/g, i.e. from 0.06 to 0.09 Bq/g. The (41)Ca/(60)Co activity ratios obtained were remarkably reproducible and in good agreement with the current ratio used for resins management. PMID:24144617

Nottoli, Emmanuelle; Bourlès, Didier; Bienvenu, Philippe; Labet, Alexandre; Arnold, Maurice; Bertaux, Maité

2013-12-01

375

Selective recovery of gold from secondary sources by Dowex-50-X8 sorbed Rhodamine-B resin.  

PubMed

Gold recovery from spent materials has been performed on modified cation-exchange resin. The modified resin was prepared by sorption of Rhodamine-B on Dowex-50-X8 (Na+) resin at pH 2.0. Distribution coefficients of gold ion have been determined with 15% (w/v) potassium chloride in different concentrations of hydrochloric acid. On the basis of Kd values quantitative separation of gold from secondary sources has been achieved. Gold(III) has been selectively separated from gold containing spent materials by column chromatography using modified ionexchange resin and the recovery was more than 92% compared to conventional cyanidation process. The results of the proposed method are suggestive of its applicability to other gold containing secondary sources. PMID:12556038

Syed, Sabir; Sharma, Lalit Mohan; Mohammad, A; Syed, Akheel Ahmed

2002-01-01

376

Sorption of beryllium from fluorine-containing solutions by amino-phosphonate amphoteric ion-exchange resins  

SciTech Connect

Sorption of beryllium ions by a series of amino-phosphonate amphoteric ion-exchange resins from BeF/sub 2/ solutions containing HF, NH/sub 4/F.HF, and NH/sub 4/F has been studied. The influence of the salt form of the resin, concentration of fluoride ions, and beryllium content in the original solutions was demonstrated. The mechanism of ion exchange on amphoteric ion-exchangers was postulated on the basis of chemical analysis and sorption and IR-spectroscopic data. Conclusions are drawn regarding the participation of phosphorus-containing groups of the resins in exchange. Data are presented on desorption of complex fluoride ions and beryllium from amphoteric ion-exchange resins by solutions of hydrofluoric, hydrochloric, and sulfuric acids, ammonium fluoride, and ammonium hydrogenfluoride.

Pakholkov, V.S.; Rychkov, V.N.

1981-10-20

377

Synthesis of improved phenolic and polyester resins  

NASA Technical Reports Server (NTRS)

Thirty-seven cured phenolic resin compositions were prepared and tested for their ability to provide improved char residues and moisture resistance over state of the art epoxy resin composite matrices. Cyanate, epoxy novolac and vinyl ester resins were investigated. Char promoter additives were found to increase the anaerobic char yield at 800 C of epoxy novolacs and vinyl esters. Moisture resistant cyanate and vinyl ester compositions were investigated as composite matrices with Thornel 300 graphite fiber. A cyanate composite matrix provided state of the art composite mechanical properties before and after humidity exposure and an anaerobic char yield of 46 percent at 800 C. The outstanding moisture resistance of the matrix was not completely realized in the composite. Vinyl ester resins showed promise as candidates for improved composite matrix systems.

Delano, C. B.

1980-01-01

378

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2011 CFR

...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1...of this chapter and the following: (1) Benzoyl chloride, poly(tetrafluoro ethylene). (2) [Reserved] (c)...

2011-04-01

379

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2010 CFR

...Surfaces § 177.1556 Polyaryletherketone resins. The poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1...of this chapter and the following: (1) Benzoyl chloride, poly(tetrafluoro ethylene). (2) [Reserved] (c)...

2010-04-01

380

An update on resin-bonded bridges.  

PubMed

Since the introduction of the 'Rochette' bridge in the 1970s the resin-bonded bridge has undergone a number of developments to become a commonly used technique for replacement of a missing tooth, especially in a minimally restored dentition. One of the major advantages of the resin-bonded bridge is that it requires less tooth preparation than conventional bridgework, with some authorities advising no preparation at all. Some reports have suggested poor long-term success rates, however, if used in appropriate clinical situations, this treatment modality can be extremely successful. The aim of this paper is to review the literature relating to resin-bonded bridges and suggest recommendations for clinicalpractice concerning the provision of resin-bonded bridges. PMID:18468318

Barber, M W; Preston, A J

2008-03-01

381

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2010 CFR

...hydrocarbons obtainable from sulfate turpentine and meeting the following specifications: Drop-softening point of 118°-138 °C; iodine value less than 20. (b) Terpene resins consisting of polymers of beta-pinene and meeting the following...

2010-04-01

382

Silicone modified resins for graphite fiber laminates  

NASA Technical Reports Server (NTRS)

The development of silicon modified resins for graphite fiber laminates which will prevent the dispersal of graphite fibers when the composites are burned is discussed. Eighty-five silicone modified resins were synthesized and evaluated including unsaturated polyesters, thermosetting methacrylates, epoxies, polyimides, and phenolics. Neat resins were judged in terms of Si content, homogeneity, hardness, Char formation, and thermal stability. Char formation was estimated by thermogravimetry to 1,000 C in air and in N2. Thermal stability was evaluated by isothermal weight loss measurements for 200 hrs in air at three temperatures. Four silicone modified epoxies were selected for evaluation in unidirectional filament wound graphite laminates. Neat samples of these resins had 1,000 C char residues of 25 to 50%. The highest flexural values measured for the laminates were a strength of 140 kpsi and a modulus of 10 Mpsi. The highest interlaminar shear strength was 5.3 kpsi.

Frost, L. W.; Bower, G. M.

1979-01-01

383

Improved high-temperature resistant matrix resins  

NASA Technical Reports Server (NTRS)

A study was performed with the objective of developing matrix resins that exhibit improved thermo-oxidative stability over state-of-the-art high temperature resins for use at temperatures up to 644 K (700 F) and air pressures up to 0.7 MPa (100 psia). The work was based upon a TRW discovered family of polyimides currently licensed to and marketed by Ethyl Corporation as EYMYD(R) resins. The approach investigated to provide improved thermo-oxidative properties was to use halogenated derivatives of the diamine, 2, 2-bis (4-(4-aminophenoxy)phenyl) hexafluoropropane (4-BDAF). Polyimide neat resins and Celion(R) 12,000 composites prepared from fluorine substituted 4-BDAF demonstrated unexpectedly lower glass transition temperatures (Tg) and thermo-oxidative stabilities than the baseline 4-BDAF/PMDA polymer.

Green, H. E.; Chang, G. E.; Wright, W. F.; Ueda, K.; Orell, M. K.

1989-01-01

384

Cesium-specific phenolic ion exchange resin  

DOEpatents

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio. 2 figs.

Bibler, J.P.; Wallace, R.M.

1995-08-15

385

Cesium-specific phenolic ion exchange resin  

DOEpatents

A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio.

Bibler, Jane P. (Aiken, SC); Wallace, Richard M. (Aiken, SC)

1995-01-01

386

Durability of Resin-Dentin Bonds to Water- vs. Ethanol-saturated Dentin  

PubMed Central

Higher 24-hour resin-dentin bond strengths are created when ethanol is used to replace water during wet bonding. This in vitro study examined if ethanol-wet-bonding can increase the durability of resin-dentin bonds over longer times. Five increasingly hydrophilic experimental resin blends were bonded to acid-etched dentin saturated with water or ethanol. Following composite build-ups, the teeth were reduced into beams for 24-hour microtensile bond strength evaluation, and for water-aging at 37°C for 3, 6, or 12 months before additional bond strength measurements. Although most bonds made to water-saturated dentin did not change over time, those made to ethanol-saturated dentin exhibited higher bond strengths, and none of them fell over time. Decreased collagen fibrillar diameter and increased interfibrillar spacing were seen in hybrid layers created with ethanol-wet-bonding. Increases in bond strength and durability in ethanol-wet-bonding may be due to higher resin uptake and better resin sealing of the collagen matrix, thereby minimizing endogenous collagenolytic activities. PMID:19278986

Hosaka, K.; Nishitani, Y.; Tagami, J.; Yoshiyama, M.; Brackett, W.W.; Agee, K.A.; Tay, F.R.; Pashley, D.H.

2009-01-01

387

Molecular Structure of Isophthalic acid  

NSDL National Science Digital Library

Isophthalic acid is one of the three simple aromatic dicarboxylic acids with the carboxyl groups in the meta postions. It is used to produce isophthalic polyester that together with other components is used in resin systems for flame retardants and in corrosion prevention.

2008-01-10

388

Effects of Porous Polystyrene Resin Parameters on Candida antarctica Lipase B Adsorption, Distribution, and Polyester Synthesis Activity  

SciTech Connect

Polystyrene resins with varied particle sizes (35 to 350-600 {mu}m) and pore diameters (300-1000 {angstrom}) were employed to study the effects of immobilization resin particle size and pore diameter on Candida antarctica Lipase B (CALB) loading, distribution within resins, fraction of active sites, and catalytic properties for polyester synthesis. CALB adsorbed rapidly (saturation time {<=}4 min) for particle sizes 120 {mu}m (pore size = 300 {angstrom}). Infrared microspectroscopy showed that CALB forms protein loading fronts regardless of resin particle size at similar enzyme loadings ({approx}8%). From the IR images, the fractions of total surface area available to the enzyme are 21, 33, 35, 37, and 88% for particle sizes 350-600, 120, 75, 35 {mu}m (pore size 300 {angstrom}), and 35 {mu}m (pore size 1000 {angstrom}), respectively. Titration with methyl p-nitrophenyl n-hexylphosphate (MNPHP) showed that the fraction of active CALB molecules adsorbed onto resins was {approx}60%. The fraction of active CALB molecules was invariable as a function of resin particle and pore size. At {approx}8% (w/w) CALB loading, by increasing the immobilization support pore diameter from 300 to 1000 {angstrom}, the turnover frequency (TOF) of {var_epsilon}-caprolactone ({var_epsilon}-CL) to polyester increased from 12.4 to 28.2 s{sup -1}. However, the {var_epsilon}-CL conversion rate was not influenced by changes in resin particle size. Similar trends were observed for condensation polymerizations between 1,8-octanediol and adipic acid. The results herein are compared to those obtained with a similar series of methyl methacrylate resins, where variations in particle size largely affected CALB distribution within resins and catalyst activity for polyester synthesis.

Chen,B.; Miller, M.; Gross, R.

2007-01-01

389

77 FR 1267 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...  

Federal Register 2010, 2011, 2012, 2013, 2014

...defined here: ABS--Acrylonitrile Butadiene Styrene Resin ADAF...Resins Source Categories A. Acrylonitrile Butadiene Styrene Resin (ABS) B...Methacrylate- 325211 1317 Acrylonitrile-Butadiene-Styrene...

2012-01-09

390

Use of ion exchange resins in the analysis of rocks and minerals: Separation of sodium and potassium  

USGS Publications Warehouse

This procedure was developed primarily for analyses in which limited amounts of sample are available. Sodium and potassium can be separated from the other constituents of silicate rocks by cation exchange resin (Amberlite IR-120). The sample is decomposed with hydrofluoric and sulfuric acids and passed through the resin bed after expulsion of the fluorine. The column is eluted with 0.12N hydrochloric acid at a fast flow rate of 4 ml. per sq. cm. per minute and the sodium and potassium are recovered together within a reasonable time. Other constituents of the sample, except silica, can be determined on the same portion of sample.

Reichen, L.E.

1958-01-01

391

Molecular Structure of Fumaric acid  

NSDL National Science Digital Library

Fumaric acid is odorless and colorless or white crystalline powder with a fruit acid taste. Fumaric acid is used as a substitute of tartaric acid in beverages and baking powders and as a replacement for citric acid in fruits drinks. It is also used as antioxidant to prevent rancidity in butter, cheese, powdered milk, and other foodstuff. In addition, fumaric acid is a chemical intermediate in the manufacture of pharmaceuticals, synthetic resins and plastics. Fumaric acid can be prepared by catalytic oxidation of benzene or by bacterial action on glucose and it is involved in the production of energy from food. Fumaric acid (known as trans-butanedioic acid) is the trans isomer of maleic acid (also called cis-butanedioic acid). Fumaric acid is more stable than maleic acid and can be prepared by heating maleic acid.

2004-11-05

392

Effect of elevated temperatures on the strength of cured resins and resin-based materials  

Microsoft Academic Search

Measurement of the loss of weight and ultimate compressive strength of phenol-formaldehyde resins under the influence of elevated temperatures has shown that during thermal degradation there is an abrupt transition from a first to a second and third structural stage with steadily increasing stabilization of the strength properties. Apart from the dependence on the heat treatment conditions, all the resins

E. B. Trostyanskaya; V. U. Novikov; Yu. N. Kazanskii

1966-01-01

393

Plastination of decalcified bone by a new resin technique  

PubMed Central

Background: The scope of this study was to preserve whole detailed structure of dissected and decalcified bones, taken from used cadavers, by a new plastination technique. Materials and Methods: Specimens we used in this study were sheep femurs and human bones including pelvis, femur, tibia, and fibula. Bones, at first, fixed with 5% formalin and were decalcified with 5% nitric acid, and then were fixed again and washed under the tap water. The resulted flexible bones were dehydrated in ?25°C acetone and degreased them in +25°C acetone. Then, the experimental and control specimen were placed in the vacuum chamber for forced impregnation with our new flexible unsaturated polyester resin (UP89 method) and silicon resin (S10 method), respectively. Finally, the strength and flexibility of plastinated decalcified specimens were investigated by tensometer, and the weight diversity was measured by digital balance. Results: Plastinated bones prepared by this technique were found to be dried, non-fragile, durable, odorless, non-greasy, and demonstrating all detailed structures of the bones. Tensile and weight tests results indicated that plastinated decalcified femurs have owned higher flexibility and strength but lesser weight than plastinated undecalcified femurs. The characteristics of both experimental and control groups of plastinated decalcified specimens were found to have no significant difference. Conclusions: Our synthesized resin found to be much more economical than conventional plastination method. In more details, properties of these new products were the same as, S10 method, from points of strength, flexibility and weight, but, since the money cost for producing them was about one fifth that of S10 method. PMID:24592368

Rabiei, Abbas Ali; Esfandiary, Ebrahim; Hajian, Morteza; Shamosi, Atefe; Mardani, Mohammad; Rashidi, Bahman; Setayeshmehr, Mohsen

2014-01-01

394

Influence of contamination on resin bond strength to nano-structured alumina-coated zirconia ceramic.  

PubMed

The purpose of this study was to evaluate the influence of contamination and subsequent cleaning on the bond strength and durability of an adhesive resin to nano-structured alumina-coated zirconia ceramic. Zirconia ceramic disks were coated with nano-structured alumina, utilizing the hydrolysis of aluminum nitride powder. After immersion in saliva or the use of a silicone disclosing agent, specimens were cleaned with phosphoric acid etching or with tap water rinsing only. Uncontaminated specimens served as controls. Plexiglas tubes filled with composite resin were bonded with a phosphate monomer [10-methacryloxydecyl-dihydrogenphosphate (MDP)]-containing resin (Panavia 21). Subgroups of eight specimens each were stored in distilled water at 37 degrees C, either for 3 d without thermal cycling (TC) or for 150 d with 37,500 thermal cycles from 5 to 55 degrees C. The tensile bond strength (TBS) was determined using a universal testing machine at a crosshead speed of 2 mm min(-1). The topography of the debonded surface was scrutinized for fractographic features, utilizing both optical and scanning electron microscopy. The TBS to uncontaminated nano-structured alumina-coated zirconia ceramic was durable, while contamination significantly reduced the TBS. Phosphoric acid cleaning was effective in removal of saliva contamination from the coated bonding surface but was not effective in removal of the silicone disclosing agent. Nano-structured alumina coating improves resin bonding to zirconia ceramic and eliminates the need for air-abrasion before bonding. PMID:20662914

Zhang, Shanchuan; Kocjan, Andraz; Lehmann, Frank; Kosmac, Tomaz; Kern, Matthias

2010-08-01

395

Qualification of Reillex{trademark} HPQ anion exchange resin for use in SRS processes  

SciTech Connect

The Phase 2 portion of the HB-Line facility was built in the early 1980's to process plutonium and neptunium from nitric acid solutions into oxide suitable for storage in a vault. Although the other portions of HB-Line were started up in the mid 1980's and have operated since that time, the anion exchange and precipitation processes in Phase 2 were never started up. As part of the material stabilization efforts, Phase 2 is currently being started up. A new anion exchange resin is needed because the resins that were proposed for use 10 years ago are limited by performance characteristics, disposal requirements, or are no longer commercially available. SRTC is responsible for qualifying all resins prior to their use in Nuclear Materials Stabilization and Storage (NMSS) processes. Qualification consists of both process suitability and thermal stability with nitric acid. This report describes the thermal stability qualification of Reillex{trademark} HPQ, the new resin proposed for processing plutonium and neptunium in the HB Line facility.

Crooks, W.J. III

2000-05-18

396

Composite Properties of Polyimide Resins Made From "Salt-Like" Solution Precursors  

NASA Technical Reports Server (NTRS)

Recent work in high temperature materials at NASA Langley Research Center (LaRC (trademark)) have led to the development of new polyimide resin systems with very attractive properties. The majority of the work done with these resin systems has concentrated on determining engineering mechanical properties of composites prepared from a poly(amide acid) precursor. Three NASA Langley-developed polyimide matrix resins, LaRC (trademark) -IA, LaRC (trademark) -IAX, and LaRC (trademark) -8515, were produced via a salt-like process developed by Unitika Ltd. The 'salt-like' solutions (sixty-five percent solids in NMP) were prepregged onto Hexcel IM7 carbon fiber using the NASA LaRC Multipurpose Tape Machine. Process parameters were determined and composite panels fabricated. Mechanical properties are presented for these three intermediate modulus carbon fiber/polyimide matrix composites and compared to existing data on the same polyimide resin systems and IM7 carbon fiber manufactured via poly(amide acid) solutions (thirty-five percent solids in NMP). This work studies the effects of varying the synthetic route on the processing and mechanical properties of polyimide composites.

Cano, Roberto J.; Weiser, Erik S.; SaintClair, Terry L.; Echigo, Yoshiaki; Kaneshiro, Hisayasu

1997-01-01

397

Resin phase spectrophotometry of beryllium by an optical fiber and beryllon II.  

PubMed

We have developed a resin phase spectrophotometric method to determine the amount of beryllium by detecting a change in absorbance of the resin phase. 8-Hydroxynaphthalene-3,6-disulphonic acid-(1-azo-2')-1',8'-dihydroxynaphthalene-3',6'-disulphonic acid tetrasodium salt (beryllon II) immobilized by a strong base anion-exchange resin on the end of a bifurcated optical fiber bundle was chosen as a material sensitive to beryllium. Experiments were made using a home-made optical fiber spectrophotometer. The properties of the resin phase proved to be good for continual use of 350 times during a month. The reaction order between immobilized beryllon II and beryllium in solution was determined by kinetic theory and experiments. This method was also used to determine the amount of beryllium in beryllium-copper alloy; the response was linear from 0.43 to 2.60 mug/ml at pH 12.5 and 676 nm. The effect of interfering ions on the determination of beryllium was studied at the same time. PMID:18965722

Xu, Y; Chen, X; Hu, Z

1993-06-01

398

Resin flow monitoring in vacuum-assisted resin transfer molding using optical fiber distributed sensor  

NASA Astrophysics Data System (ADS)

In this study, we implemented resin flow monitoring by using an optical fiber sensor during vacuum assisted resin transfer molding (VaRTM).We employed optical frequency domain reflectometry (OFDR) and fiber Bragg grating (FBG) sensor for distributed sensing. Especially, long gauge FBGs (about 100mm) which are 10 times longer than an ordinary FBG were employed for more effective distributed sensing. A long gauge FBG was embedded in GFRP laminates, and other two ones were located out of laminate for wavelength reference and temperature compensation, respectively. During VaRTM, the embedded FBG could measure how the preform affected the sensor with vacuum pressure and resin was flowed into the preform. In this study, we intended to detect the gradient of compressive strain between impregnated part and umimpregnated one within long gauge FBG. If resin is infused to preform, compressive strain which is generated on FBG is released by volume of resin. We could get the wavelength shift due to the change of compressive strain along gauge length of FBG by using short-time Fourier transformation for signal acquired from FBG. Therefore, we could know the resin flow front with the gradient of compressive strain of FBG. In this study, we used silicon oil which has same viscosity with resin substitute for resin in order to reuse FBG. In order to monitor resin flow, the silicon oil was infused from one edge of preform, the silicon oil was flowed from right to left. Then, we made dry spot within gauge length by infusing silicon oil to both sides of preform to prove the ability of dry spot monitoring with FBG. We could monitor resin flow condition and dry spot formation successfully using by FBG based on OFDR.

Eum, Soohyun; Kageyama, Kazuro; Murayama, Hideaki; Ohsawa, Isamu; Uzawa, Kiyoshi; Kanai, Makoto; Igawa, Hirotaka

2007-04-01

399

Anion-exchange resin-based desulfurization process  

SciTech Connect

The University of Tennessee Space Institute (UTSI) has a Department of Energy grant to further develop the Institute's anion-exchange resin-based flue gas, desulfurization concept. The developmental program proposed includes screening of commercially available resins to select three candidate resins for further study. These three resins will undergo a series of experiments designed to test the resins' performance under different process conditions (including the use of spent MHD seed material). The best of these resins will be used in optimizing the regeneration step and in testing the effects of performance enhancers. The process schematic developed from the results will be used to estimate the related economics.

Sheth, A.C.; Strevel, S.D.

1991-01-01

400

Antistaphylococcal and biofilm inhibitory activities of acetyl-11-keto-?-boswellic acid from Boswellia serrata  

Microsoft Academic Search

Background  Boswellic acids are pentacyclic triterpenes, which are produced in plants belonging to the genus Boswellia. Boswellic acids appear in the resin exudates of the plant and it makes up 25-35% of the resin. ?-boswellic acid, 11-keto-?-boswellic\\u000a acid and acetyl-11-keto-?-boswellic acid have been implicated in apoptosis of cancer cells, particularly that of brain tumors\\u000a and cells affected by leukemia or colon

Alsaba F Raja; Furqan Ali; Inshad A Khan; Abdul S Shawl; Daljit S Arora; Bhahwal A Shah; Subhash C Taneja

2011-01-01

401

Diffusion of residual monomer in polymer resins.  

PubMed Central

A simplified mathematical model which made use of Fick's laws of diffusion written in spherical coordinates was developed to describe the rate of diffusion of residual monomers from polymer resins. The properties of the monomer-polymer system which influenced the amount of monomer remaining in the polymer as a function of time were the diffusivity and solubility of the monomer in the polymer, and the particle size of the polymer resin. This model was used to analyze literature data on the diffusion of residual vinyl chloride monomer in polyvinyl chloride resins made by the suspension process. It was concluded that particle size of the resin was a significant parameter which should be taken advantage of in process equipment designed to remove residual monomer from PVC resins. The diffusivity of the monomer in the polymer was a function of the solubility of the monomer in the polymer. Monomer solubility can be determined from Henry's law. It was suggested that this model could be adapted to describe diffusion of monomers from any monomer-polymer system, and would be a useful approach to modeling the transport of nonreactive chemical additives from plastics. PMID:1026410

Piver, W T

1976-01-01

402

Development of a heterogeneous laminating resin system  

NASA Technical Reports Server (NTRS)

The factors which effect the impact resistance of laminating resin systems and yet retain equivalent performance with the conventional 450 K curing epoxy matrix systems in other areas were studied. Formulation work was conducted on two systems, an all-epoxy and an epoxy/bismaleimide, to gain fundamental information on the effect formulation changes have upon neat resin and composite properties. The all-epoxy work involved formulations with various amounts and combinations of eight different epoxy resins, four different hardeners, fifteen different toughening agents, a filler, and a catalyst. The epoxy/bismaleimide effort improved formulations with various amounts and combinations of nine different resins, four different hardeners, eight different toughening agents, four different catalysts, and a filler. When a formulation appeared to offer the proper combination of properties required for a laminating resin Celion 3K-70P fabric was prepregged. Initial screening tests on composites primarily involved Gardner type impact and measurement of short beam shear strengths under dry and hot/wet conditions.

Biermann, T. F.; Hopper, L. C.

1985-01-01

403

76 FR 3614 - Granular Polytetrafluoroethylene Resin From Japan: Final Results of Sunset Review and Revocation...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Granular Polytetrafluoroethylene Resin From Japan: Final Results of Sunset Review and Revocation...polytetrafluoroethylene resin (``PTFE resin'') from Japan. See Initiation of Five-Year (``Sunset...duty order on imports of PTFE resin from Japan. See Antidumping Duty Order;...

2011-01-20

404

76 FR 42114 - Granular Polytetrafluoroethylene Resin From Italy: Continuation of Antidumping Duty Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Granular Polytetrafluoroethylene Resin From Italy: Continuation of Antidumping Duty Order...polytetrafluoroethylene resin (``PTFE resin'') from Italy would likely lead to a continuation or...antidumping duty order on PTFE resin from Italy, pursuant to section 751(c)(2)...

2011-07-18

405

76 FR 12939 - Granular Polytetrafluoroethylene Resin From Italy: Final Results of Expedited Sunset Review of...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Granular Polytetrafluoroethylene Resin From Italy: Final Results of Expedited Sunset Review...polytetrafluoroethylene resin (``PTFE resin'') from Italy. The Department has conducted an expedited...antidumping duty order on PTFE resin from Italy pursuant to section 751(c) of the...

2011-03-09

406

PETIs as High-Temperature Resin-Transfer-Molding Materials  

NASA Technical Reports Server (NTRS)

Compositions of, and processes for fabricating, high-temperature composite materials from phenylethynyl-terminated imide (PETI) oligomers by resin-transfer molding (RTM) and resin infusion have been developed. Composites having a combination of excellent mechanical properties and long-term high-temperature stability have been readily fabricated. These materials are particularly useful for the fabrication of high-temperature structures for jet-engine components, structural components on highspeed aircraft, spacecraft, and missiles. Phenylethynyl-terminated amide acid oligomers that are precursors of PETI oligomers are easily made through the reaction of a mixture of aromatic diamines with aromatic dianhydrides at high stoichiometric offsets and 4-phenylethynylphthalic anhydride (PEPA) as an end-capper in a polar solvent such as N-methylpyrrolidinone (NMP). These oligomers are subsequently cyclodehydrated -- for example, by heating the solution in the presence of toluene to remove the water by azeotropic distillation to form low-molecular-weight imide oligomers. More precisely, what is obtained is a mixture of PETI oligomeric species, spanning a range of molecular weights, that exhibits a stable melt viscosity of less than approximately 60 poise (and generally less than 10 poise) at a temperature below 300 deg C. After curing of the oligomers at a temperature of 371 deg C, the resulting polymer can have a glass-transition temperature (Tg) as high as 375 C, the exact value depending on the compositions.

Connell, John N.; Smith, Joseph G., Jr.; Hergenrother, Paul M.

2005-01-01

407

A microcapsule containing chelating resin selective for cadmium (II).  

PubMed

Ion exchange and solvent extraction technologies have been widely used for uptake and recovery of heavy metals from aqueous phases. However, different problems have been encountered on applying these techniques. Alternative to overcome these limitations is the microcapsulation of extractants within a functionalized polymeric shell. A chelating resin was prepared by treating Ceralite IR 400 with chromotropic acid and characterized by FTIR spectrum and sulphur analysis. Then, polystyrene microcapsules containing chelating resin were prepared by interfacial copolymerization of w/o/w emulsions. The adsorption of Zn(II), Cd(II), Ni(II), Co(II), Cu(II) and Pb(II) into microcapsule was studied by batch experiments. The effect of pH and counter ions on adsorption behavior has been investigated. Maximum uptake of Cd(II) into microcapsule was found in the presence of I ions and remained unchanged in the pH range 1-7 and the Cd(II) ions remained unaffected in the microcapsule even in 1 M HCl solution. The selectivity for Cd(II) was over four times greater than the other investigated metal ions. The breakthrough capacity for Cd(II) was 2.68 m mol/g microcapsule. The microcapsule packed mini-column has been applied for separation of Cd(II) from Zn(II), Pb(II), Cu(II), Ni(II) and Co(II). The microcapsule has also been tested for selective recovery of Cd(II) from river water. PMID:23505815

Gehlot, C L; Singh, Anuradha

2011-10-01

408

Polycarboxylated microfillers incorporated into light-curable resin-based dental adhesives evoke remineralization at the mineral-depleted dentin.  

PubMed

This study aimed at evaluating the remineralizing properties of three experimental light-curable resin-based dental adhesives containing tailored polycarboxylated microfillers. A co-monomers blend was firstly formulated and then mixed with each of the following microfillers: polycarboxylated bioactive glass (PBAG), polycarboxylated calcium silicates (PCS), and polycarboxylated calcium silicates-doped brushite (PDP). The three experimental and a filler-free control resins were applied onto 10% orthophosphoric acid treated dentin discs and light cured. The specimens were soaked in artificial saliva (AS) for 3, 7, and 14?days. Dentin mineral variation was monitored using attenuated total reflection-Fourier transform infrared (ATR-FTIR) and Raman spectroscopy. Confocal laser scanning microscopy (CLSM) was employed to observe the ultra-morphology/nanoleakage along the resin-dentin interface. The bonding ability and the durability of the resin-dentin bonds were investigated through microtensile bond strength (?TBS) test. ATR-FTIR and Raman showed a significant increase of the mineral matrix area ratio and phosphate peak intensity in specimens treated with the experimental resins within 14?days (p?resin (p?>?0.05). Dentin treated using PBAG or PCS exhibited higher level of remineralization than the specimens in PDP group. CLSM showed reduction in nanoleakage, although the remineralization of the hybrid layer induced a significant drop in the ?TBS after 3-month storage (p?resin-based dental adhesives containing bioactive microfillers remineralize the resin-dentin interfaces when in intimate contact with biological fluids. PMID:24597956

Wang, Zhejun; Shen, Ya; Haapasalo, Markus; Wang, Jiao; Jiang, Tao; Wang, Yining; Watson, Timothy F; Sauro, Salvatore

2014-01-01

409

Setting reaction of polyacid modified composite resins or compomers.  

PubMed

The hardening of modified polyacid composite resins (compomers) and glass-ionomers have been studied using infrared spectroscopy. The acid-base reaction in Ketac-fil, a glass ionomer, was followed by the ratio between the COOH band located around 1715 cm?¹ and that corresponding to COO? located around 1570 cm?¹. The combination of infrared analysis and band narrowing treatments enable us to propose in the glass-ionomer two maturation steps. First, a very rapid equilibrium acid-base related, and second the cross-linking of polycarboxylate with the metal ions present in the cement. In compomers, a new reaction has been described involving polymerization induced by free radicals besides the two steps associated with the acid-base reaction. Using infrared spectroscopy and band narrowing techniques, it is shown that water is essential to complete the hardening process but no acid-base reaction is produced since the COO? band does not appear. The reaction associated with free radicals could be described as a polymerization of methacrylate monomers together with an aqueous dilution of the filling particles releasing different metal cations that would chelate with the polymer molecules to form a macromolecular structure. PMID:19834564

Arrondo, J L R; Collado, M I; I, Soler; Triana, R; Ellacuria, J

2009-01-01

410

Additive effects on the toughening of unsaturated polyester resins  

SciTech Connect

An elastomer additive, carboxy-terminated acrylonitrile-butadiene copolymer, was used for toughening in the free radical cross-linking copolymerization of unsaturated polyester (UP) resins. For molded parts, Charpy impact behavior was generally enhanced and the number of catastrophic failures was reduced. The miscibility and interfacial properties of additive and resin blends play important roles in the toughening process. Phase-diagram studies showed that the elastomer additive is immiscible with the UP resin and is phase-separated from the resin matrix during curing. This phase-separation phenomenon is similar to that in the low-profile mechanism of UP resins. Additive-resin system miscibility greatly influences curing morphology. Microvoids occurred in the additive phase of cured resin because of shrinkage stress. The intrinsic inhomogeneity of the polyester network and the existence of microvoids in the final product limit the toughening effect of additives on unsaturated polyester resins. 49 refs., 13 figs., 3 tabs.

Suspene, L. [Centre de Recherches et de Technologies de Verneuil, Verneuil-en-Halatte (France); Yang, Y.S.; Pascault, J.P. [Institut National des Science Appliquees de Lyon, Villeurbanne (France)

1993-12-31

411

Performance Properties of Graphite Reinforced Composites with Advanced Resin Matrices  

NASA Technical Reports Server (NTRS)

This article looks at the effect of different resin matrices on thermal and mechanical properties of graphite composites, and relates the thermal and flammability properties to the anaerobic char yield of the resins. The processing parameters of graphite composites utilizing graphite fabric and epoxy or other advanced resins as matrices are presented. Thermoset resin matrices studied were: aminecured polyfunctional glycidyl aminetype epoxy (baseline), phenolicnovolac resin based on condensation of dihydroxymethyl-xylene and phenol cured with hexamine, two types of polydismaleimide resins, phenolic resin, and benzyl resin. The thermoplastic matrices studied were polyethersulfone and polyphenylenesulfone. Properties evaluated in the study included anaerobic char yield, limiting oxygen index, smoke evolution, moisture absorption, and mechanical properties at elevated temperatures including tensile, compressive, and short-beam shear strengths. Generally, it was determined that graphite composites with the highest char yield exhibited optimum fire-resistant properties.

Kourtides, Demetrius A.

1980-01-01

412

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

Code of Federal Regulations, 2014 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2014-04-01

413

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

Code of Federal Regulations, 2013 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2013-04-01

414

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

Code of Federal Regulations, 2010 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2010-04-01

415

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

Code of Federal Regulations, 2012 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2012-04-01

416

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

Code of Federal Regulations, 2011 CFR

...?-Methylstyrene-vinyltoluene resins, hydrogenated. Hydrogenated ?-methylstyrene-vinyltoluene copolymer resins having a molar ratio of 1 ?-methylstyrene to 3 vinyltoluene may be safely used as components of polyolefin film intended for use in...

2011-04-01

417

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650 Section...CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components...Surfaces § 177.1650 Polysulfide polymer-polyepoxy resins....

2012-04-01

418

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650 Section...CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components...Surfaces § 177.1650 Polysulfide polymer-polyepoxy resins....

2013-04-01

419

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650 Section...CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components...Surfaces § 177.1650 Polysulfide polymer-polyepoxy resins....

2014-04-01

420

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2013 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2013-04-01

421

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2010 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2010-04-01

422

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2014 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2014-04-01

423

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2012 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2012-04-01

424

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2011 CFR

...the purpose of this section the mineral reinforced nylon resins consist of nylon 66, as identified in and complying with the specifications...calcium silicate. (b) The mineral reinforced nylon resins may contain up to 0.2 percent by...

2011-04-01

425

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2011-04-01

426

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin...

2013-04-01

427

21 CFR 872.3200 - Resin tooth bonding agent.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3200 Resin tooth bonding agent. (a) Identification. A resin tooth bonding agent is a...

2014-04-01

428

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2010-04-01

429

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a...

2013-04-01

430

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin...

2011-04-01

431

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2010 CFR

...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

2010-04-01

432

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2011 CFR

...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

2011-04-01

433

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2014 CFR

...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

2014-04-01

434

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2012 CFR

...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

2012-04-01

435

21 CFR 872.3690 - Tooth shade resin material.  

Code of Federal Regulations, 2013 CFR

...Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl methacrylate (Bis-GMA) intended to restore carious lesions or structural defects in teeth. (b)...

2013-04-01

436

Standard tests for toughened resin composites, revised edition  

NASA Technical Reports Server (NTRS)

Several toughened resin systems are evaluated to achieve commonality for certain kinds of tests used to characterize toughened resin composites. Specifications for five tests were standardized; these test standards are described.

1983-01-01

437

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2013 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2013-04-01

438

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2012 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2012-04-01

439

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2010 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2010-04-01

440

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2011 CFR

...FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2011-04-01

441

21 CFR 172.215 - Coumarone-indene resin.  

Code of Federal Regulations, 2014 CFR

...HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Coatings, Films and Related Substances § 172.215 Coumarone-indene resin. The food additive coumarone-indene resin may be...

2014-04-01

442

Occupational dermatitis to epoxydic and phenolic resins.  

PubMed

Contact dermatitis to epoxydic and phenolic resins are the most frequent contact dermatoses due to plastics, in particular in the form of airborne dermatitis. The chemical formulas of the various components of these resins and their additives are complex and the patch tests available in the trade are insufficient and often arrive at a late stage in the progress of industry, in particular in advanced technologies like aeronautical engineering, shipbuilding or the new floor and wall coverings in buildings. This article is a review of the actions to be taken with these allergies, as well as with regards to their diagnosis, prevention and medico-legal compensation. PMID:19349256

Geraut, Christian; Tripodi, Dominique; Brunet-Courtois, Béatrice; Leray, Fabrice; Geraut, Laurent

2009-01-01

443

Technical assessment for quality control of resins  

NASA Technical Reports Server (NTRS)

Survey visits to companies involved in the manufacture and use of graphite-epoxy prepregs were conducted to assess the factors which may contribute to variability in the mechanical properties of graphite-epoxy composites. In particular, the purpose was to assess the contributions of the epoxy resins to variability. Companies represented three segments of the composites industry - aircraft manufacturers, prepreg manufacturers, and epoxy resin manufacturers. Several important sources of performance variability were identified from among the complete spectrum of potential sources which ranged from raw materials to composite test data interpretation.

Gosnell, R. B.

1977-01-01

444

Resin transfer molding of textile composites  

NASA Technical Reports Server (NTRS)

The design and manufacture of textile composite panels, tubes, and angle sections that were provided to NASA for testing and evaluation are documented. The textile preform designs and requirements were established by NASA in collaboration with Boeing and several vendors of textile reinforcements. The following four types of preform architectures were used: stitched uniweave, 2D-braids, 3D-braids, and interlock weaves. The preforms consisted primarily of Hercules AS4 carbon fiber; Shell RSL-1895 resin was introduced using a resin transfer molding process. All the finished parts were inspected using ultrasonics.

Falcone, Anthony; Dursch, Harry; Nelson, Karl; Avery, William

1993-01-01

445

The role of MDP in a bonding resin of a two-step self-etching adhesive system.  

PubMed

The purpose of this study was to evaluate the role of 10-methacryloyloxydecyl dihydrogen phosphate (MDP) contained in the bonding resin of a two-step self-etch adhesive system. An experimental adhesive (M0) containing MDP only in the primer, but not in the bonding resin was prepared. Clearfil SE Bond (MM) and M0 were compared in terms of microtensile bond strength to dentin, ultimate tensile strength of the bonding resin, and dentin-resin bonding interface morphology under SEM and TEM. The immediate µTBS values of MM significantly decreased after thermal cycles while M0 were stable even after 10,000 cycles. In the SEM observations, formation of erosion was observed beneath the acid-base resistant zone only in M0. The results suggested that MDP in the bonding resin of the two-step self-etching system; 1) improved the immediate bond strength, but caused reduction in long-term bond durability; 2) offered the advantages of acid-base resistance at the ABRZ forefront area. PMID:25740167

Matsui, Naoko; Takagaki, Tomohiro; Sadr, Alireza; Ikeda, Masaomi; Ichinose, Shizuko; Nikaido, Toru; Tagami, Junji

2015-04-01

446

??????????????????????????????????????????????????????????????????????? D2EHPA SEPARATION OF URANIUM FROM TRISODIUM PHOSPHATE SOLUTION BY D2EHPA IMPREGNATED RESINS ????????? ???????????1, ??????? ??????????1 ??? ????? ????????????1  

Microsoft Academic Search

In the monazite ore breakdown by alkali process to separate nuclear elements and rare earth elements composed in this phosphate ore, trisodium phosphate byproduct from the digestion process may contain uranium up to 300 ppm. Therefore, it is necessary to purify this trisodium phosphate. This study has used di(2-ethylhexyl) phosphoric acid (D2EHPA) impregnated resins to extract uranium from the trisodium

Uthaiwan Injarean; Pipat Pichestapong; Wannee Srinuttrakul

447

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Polyester resin kits. 173.165 Section 173.165...Other Than Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Polyester resin kits consisting of a base material...

2013-10-01

448

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Polyester resin kits. 173.165 Section...Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Except for transportation by aircraft, polyester resin kits consisting of a base...

2012-10-01

449

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Polyester resin kits. 173.165 Section...Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Except for transportation by aircraft, polyester resin kits consisting of a base...

2011-10-01

450

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Polyester resin kits. 173.165 Section 173.165...Other Than Class 1 and Class 7 § 173.165 Polyester resin kits. (a) Polyester resin kits consisting of a base material...

2014-10-01

451

Seasonal variation in the leaf resin components of Mimulus aurantiacus  

Microsoft Academic Search

The chaparral subshrub, Mimulus aurantiacus, produces leaf surface resins in excess of 30% of leaf dry weight. The resin provides some defense against the insect herbivore, Euphydryas chalcedona, and perhaps from desiccation and injury from UV light. The resin comprises six flavanones and an ?-pyrone. The different components may differ in their ecological roles. Methoxylated components may be most effective

J. Daniel Hare

2002-01-01

452

Bismaleimide resins for flame resistant honeycomb sandwich panels  

NASA Technical Reports Server (NTRS)

A 60 kg batch of Resin M751 was produced in pilot plant scale. The resin was delivered to the prepreg company as an NMP solution. 100 kg of glass-fabric prepregs were fabricated. Prepreg characteristics and curing cycles for laminate fabrication were provided. A new batch of Resin M756 (Code M756 - 2) was synthesized.

1978-01-01

453

Urea–formaldehyde (UF) adhesive resins for wood  

Microsoft Academic Search

Urea–formaldehyde (UF) resins are the most important type of adhesive resins for the production of wood based panels. They convince by their high reactivity and good performance in the production and by their low price, however they lack in water resistance of the hardened resin owing to the reversibility of the aminomethylene link and hence the susceptibility to hydrolysis. This

M. Dunky

1998-01-01

454

Occupational asthma due to unheated polyvinylchloride resin dust.  

PubMed Central

Polyvinylchloride (PVC) resins are widely used in industry. Asthma due to the thermal degradation products of PVC are well documented. In this first case of occupational asthma due to unheated PVC resin dust the patient was exposed to PVC resin dust during the mixing of chemicals used for making plastic seals for bottle caps. PMID:2590649

Lee, H S; Yap, J; Wang, Y T; Lee, C S; Tan, K T; Poh, S C

1989-01-01

455

Actinide Binding by Kläui Ligands: REDOX Speciation and Sorption on an Extraction Chromatography Resin  

SciTech Connect

The sorption of Eu(III) and actinide ions in various oxidation states from nitric acid solutions by an extraction chromatography resin containing 1 wt% of the Kläui ligand Cp*Co[P(O)(OR)2]3– [Cp* = pentamethylcyclopentadienyl, R = –CH2 CH2CH3] on Amberlite® XAD-7HP was examined. At 0.3 M HNO3 and a metal-to-ligand ratio of 0.07, the relative affinity of the resin for the ions investigated followed the order: tetravalent >> hexavalent > trivalent > pentavalent; however, the relative affinity for the trivalent and hexavalent ions can be reversed, depending on the extent of ligand loading and the nitric acid concentration. The sorption of the tetravalent ions was exceptionally strong in the entire range of nitric acid concentration examined (0.2 to 8 M HNO3). Resin samples loaded with various actinide ions were examined spectrophotometrically. No Np(V) and Pu(III) species were identified on the resin; rather, reduction-oxidation (REDOX) reactions occurred during equilibration, resulting in their complete conversion to M(IV) species bound by the Kläui ligand. Similarly, the sorption behavior of Pu(VI) and Np(VI) was complicated by their reduction to M(IV) upon sorption. The observed REDOX processes were apparently driven by the extremely high affinity of the Kläui ligand for the tetravalent ions. The acid-base properties of the methyl derivative of the Kläui ligand were investigated in aqueous solution, and its pKa was found to be highly dependent upon the solution ionic strength. The binding constants of this ligand with various actinide ions measured in a mixed methanol/carbon tetrachloride solvent exhibited qualitative agreement with the sorption selectivity trends.

Levitskaia, Tatiana G.; Sinkov, Sergey I.; Lumetta, Gregg J.

2008-12-01

456

Ceramicrete{trademark} Stabilization of CST Resin: ITP Alternative Phase III Feasibility Study  

Microsoft Academic Search

The Ceramicrete{trademark} waste form is a magnesium phosphate hydrate, which sets as the result of an acid-base reaction between KHâPOâ and MgO in the presence of water. Based on the results of this feasibility study, this low temperature ceramic waste form is acceptable for stabilization of cesium loaded crystalline silicotitanate (CST) resin. The performance objective of CST stabilization is to

Langton

1998-01-01

457

Bark extractives-based phenol–formaldehyde resins from beetle-infested lodgepole pine  

Microsoft Academic Search

In this study, phenol–formaldehyde (PF) resins derived from the bark extractives were synthesized and characterized. Bark of lodgepole pine (Pinus contorta Dougl.) infested by mountain pine beetle (Dendroctonus ponderosae Hopkins) was first extracted with 1% NaOH. The bark extractives with and without acid-neutralization were then dried to the solid state. The neutralized and non-neutralized extractives were used to partially replace

Yong Zhao; Ning Yan; Martin W. Feng

2012-01-01

458

Ion exchange equilibria of heavy metals in aqueous solution on new chelating resins of sporopollenin  

Microsoft Academic Search

Studies have been conducted on the sorption of several heavy metal ions Cu(II), Ni(II), Zn(II), Cd(II) and Al(III) from aqueous solutions on the new chelating exchangers of sporopollenin (Lycopodium clavatum) as a function of pH at several temperatures between 20 and 50°C. The novel metal-ligand exchange resins possessing oxime and carboxylic acid side arm functionality were prepared through the reaction

M. Ersoz; E. Pehlivan; H. J. Duncan; S. Yildiz; M. Pehlivan

1995-01-01

459

Uptake of metal ions by a new chelating ion exchange resin. Part 3: Protonation constants via potentiometric titration and solid state [sup 31]P NMR spectroscopy  

SciTech Connect

A new chelating ion exchange resin which incorporates methylenediphosphonate, carboxylate, and sulfonate functional groups in a polystyrene-divinylbenzene matrix has been prepared. This resin exhibits exceptionally high affinity for polyvalent cations even from moderately acidic aqueous media. Metal ion coordination occurs primarily at the diphosphonate group with the secondary binding sites contributing to charge neutralization when necessary and possible, and to increasing hydrophilicity of the resin pores. In the present investigation, the protonation equilibria of the phosphonate groups in the resin are investigated via potentiometric titration and solid-state [sup 31]P NMR spectroscopy of the resin. Intrinsic equilibrium constants for the first two diphosphonate protonation reactions are pK[sub 4] = 10.47 and pK[sub 3] = 7.24. The last two protons added to the diphosphonate group are acidic having pK[sub a] values less than 2.5. These protonation constants are consistent with those reported previously for monomer analog 1,1-diphosphonic acids. This result implies that thermodynamic data available in the literature can be used to predict the relative affinity of the resin for polyvalent cations. 17 refs., 2 figs., 3 tabs.

Nash, K.L.; Rickert, P.G.; Muntean, J.V.; Alexandratos, S.D.

1994-01-01

460

Method of recovering hazardous waste from phenolic resin filters  

SciTech Connect

A method has been found for treating phenolic resin filter, whereby the filter is solubilized within the filter cartridge housing so the filter material can be removed from the cartridge housing in a remote manner. The invention consists of contacting the filter within the housing with an aqueous solution of about 8 to 12M nitric acid, at a temperature from about 110 to 190{degree}F, maintaining the contact for a period of time sufficient to solubilize the phenolic material within the housing, and removing the solubilized phenolic material from the housing, thereby removing the filter cartridge from the housing. Any hazardous or other waste material can then be separated from the filter material by chemical or other means.

Meikrantz, D.H.; Bourne, G.L.; McFee, J.N.; Burdge, B.G.; McConnell, J.W. Jr.

1990-12-31

461

Chromate (CrO(4)(2-)) and copper (Cu2+) adsorption by dual-functional ion exchange resins made from agricultural by-products.  

PubMed

Ion exchange resins commonly have a single functionality for either cations or anions. Resins that have a dual functionality for both cations and anions are uncommon. The objective of this study was to create dual-functional ion exchange resins derived from soybean hulls, sugarcane bagasse and corn stover. Dual-functional resins were prepared by two separate two-step processes. In the first two-step process, by-products were reacted with a solution of citric acid in order to impart additional negative charge, and then reacted with the cross-linking reagent dimethyloldihydroxyethylene urea (DMDHEU) and a quaternary amine (choline chloride) to add positive charge to the lignocellulosic material. In the second two-step process, the order of reaction was reversed, with positive charge added first, followed by the addition of negative charge. These combined reactions added both cationic and anionic character to the by-products as evidenced by the increased removal from solution of copper (Cu(2+)) cation and the chromate (CrO(4)(2-)) anion compared to unmodified by-products. The order of reaction appeared to slightly favor the functionality that was added last. That is, if negative charge was added last, the resulting resin sequestered more copper ion than a comparable resin where the negative charge was added first and vice-versa. Cu(2+) and CrO(4)(2-) were used as marker ions in a solution that contained both competing cations and anions. The dual-functional resins adsorbed as much as or more of the marker ions compared to commercial cation or anion exchange resins used for comparison. None of the commercial resins exhibited dual-functional properties to the same extent as the by-product-based resins. PMID:16764901

Marshall, Wayne E; Wartelle, Lynda H

2006-07-01

462

Low-melt Viscosity Polyimide Resins for Resin Transfer Molding (RTM) II  

NASA Technical Reports Server (NTRS)

A series of polyimide resins with low-melt viscosities in the range of 10-30 poise and high glass transition temperatures (Tg s) of 330-370 C were developed for resin transfer molding (RTM) applications. These polyimide resins were formulated from 2,3,3 ,4 -biphenyltetracarboxylic dianhydride (a-BPDA) with 4-phenylethynylphthalic anhydride endcaps along with either 3,4 - oxyaniline (3,4 -ODA), 3,4 -methylenedianiline, (3,4 -MDA) or 3,3 -methylenedianiline (3,3 -MDA). These polyimides had pot lives of 30-60 minutes at 260-280 C, enabling the successful fabrication of T650-35 carbon fiber reinforced composites via RTM process. The viscosity profiles of the polyimide resins and the mechanical properties of the polyimide carbon fiber composites will be discussed.

Chuang, Kathy C.; Criss, Jim M.; Mintz, Eric A.; Scheiman, Daniel A.; Nguyen, Baochau N.; McCorkle, Linda S.

2007-01-01

463

On the Fatigue Behavior of Resin-Dentin Bonds after Degradation by Biofilm  

PubMed Central

The durability of resin-dentin bonds is a growing concern in the placement of composite restorations. Most reported evaluations concerning the mechanical behavior of the bonded interface are conducted using static loading to failure only. They also do not account for the acid production of biofilms, which is one of the most common contributors to interfacial failures in vivo. In this investigation resin-dentin bonded interface specimens were exposed to S. mutans for 14 days and then subjected to quasi-static or cyclic four-point flexure to failure. Control specimens (without biofilm) were evaluated after aging for one and fourteen days. While no significant difference in flexure strength resulted from the duration of water aging (66.2 MPa vs 56.9 MPa), biofilm exposure caused a significant reduction in strength (29.3 MPa; p?0.000). After water aging for one and fourteen days the apparent endurance limits were 13.0 MPa and 13.1 MPa, respectively. Biofilm treatment caused a significant (p?0.001) reduction in fatigue resistance of the interface, and the endurance limit was reduced to 9.9 MPa. Fatigue failure of the control specimens initiated within the resin composite adjacent to the interface, whereas failure of the biofilm treated specimens initiated within the hybrid layer and appeared attributed to the localized demineralization of dentin. Biofilm degradation is an important consideration in assessing the durability of resin-dentin bonds. PMID:23276517

Mutluay, Mustafa Murat; Zhang, Ke; Ryou, Heonjune; Yahyazadefar, Mobin; Majd, Hessam; Xu, Hockin H. K.; Arola, Dwayne

2012-01-01

464

Effects of sports beverages and polishing systems on color stability of different resin composites  

PubMed Central

Background: Consumption of certain acidic beverages may alter the physical and esthetic properties of resin composites. Aim: The aim of this study was to evaluate the effects of two sports beverages on color stability of two different types of resin composites polished with different composite polishing systems. Materials and Methods: A total of 96 disk-shaped specimens (diameter: 8-mm and thickness: 2-mm) were made from two different resin composites (Cavex Quadrant Universal-LC, and Clearfil-APX). All of the specimens were stored in distilled water for 24 h at 37°C. Color measurements of each specimen were performed using a colorimeter according to the CIEL*a*b* color scale at baseline and after seven days of immersion in two different sports beverages (Powerade and Buzzer). Statistical Analysis Used: The data were evaluated using Kruskal Wallis and Mann-Whitney U tests. Results: Significant differences were found between the mean ?E values of the groups after seven days of immersion (P < 0.05). The highest level of the mean color change was observed in the Clearfil APX specimens immersed in Powerade (?E = 3.5 ± 0.9). Control groups stored in distilled water for both composites exhibited small color changes (?E-Cavex-bur = 2.1 ± 1; ?E-Clearfil APX-bur = 2.1 ± 0.4). Conclusion: Sport beverages caused discoloration in the resin composites after seven days. PMID:25125843

Ta?k?nsel, Ertan; Özel, Emre; Öztürk, Elif

2014-01-01

465

Ion-pair sorption of alkali metal chlorides by crown ether carboxamide resins  

SciTech Connect

Ten crown ether carboxamide resins are prepared by condensation polymerization of N,N-dialkyl sym-(R)dibenzo-16-crown-5-oxyacetamide monomers with formaldehyde in formic acid. Competitive ion-pair sorption of alkali metal chlorides from aqueous methanol solutions by these novel resins reveals that both sorption selectivity and efficiency are influenced by: (1) the conformational positioning of the pendant carboxamide group with respect to the crown ether cavity; (2) the length of the N,N-dialkyl chains on the pendant carboxamide group; (3) the methanol content of the aqueous methanol solution; (4) the concentration of alkali metal chlorides in the sample solution; and (5) the temperature of the sample solution. The highest sorption efficiency and Na{sup +} selectivity are obtained for a resin prepared from N,N-dibutyl sym-(propyl)dibenzo-16-crown-5-oxacetamide monomer in which the geminal propyl group orients the carboxamide-containing side arm over the crown ether cavity. Lengthening the alkyl chains in the carboxamide group is detrimental to both sorption efficiency and selectivity. A very sharp response of alkali metal chloride sorption to the methanol content of the sample solution is noted for the crown ether resins which possess preorganized carboxamide side arms.

Hayashita, Takashi; Yamasaki, Kenji [Saga Univ., Honjo-Machi, Saga (Japan); White, J.C. [Texas Tech Univ., Lubbock, TX (United States)] [and others

1996-09-01

466

Glutathione Resins I. List of Components  

E-print Network

that is applicable for up to 50 g of E. coli cells. Other extraction methods can be used with varying recovery purifications of up to 10 mg of GST-tagged protein per column. · Five Glutathione-Uniflow Columns Each column Clontech · www.clontech.com · 800-662-2566 #12;GlutathioneResinProtocol · Polypropylene tubes · Centrifuge

Lebendiker, Mario

467

REMOVING RADIUM-226 ION EXCHANGE RESINS  

E-print Network

1 1 REMOVING RADIUM-226 FROM ION EXCHANGE RESINS USED IN DRINKING WATER TREATMENT James McMahon Dr) SEPTEMBER 22, 2007 2 Presentation Outline · Radionuclide/Radium-226 Regulations · Radium-226 Treatment for Radionuclides · 1962 US Public Health Services DWS ­ 3 pCi/L Radium 226 · 1977 USEPA National Interim Prim. DWS

468

Pharmaceutical Applications of Ion-Exchange Resins  

ERIC Educational Resources Information Center

The historical uses of ion-exchanged resins and a summary of the basic chemical principles involved in the ion-exchanged process are discussed. Specific applications of ion-exchange are provided that include drug stabilization, pharmaceutical excipients, taste-masking agents, oral sustained-release products, topical products for local application…

Elder, David

2005-01-01

469

A model for resin viscosity during cure in the resin transfer moulding process  

Microsoft Academic Search

A cure model has been developed for the viscosity of two-part epoxy\\/amine resins, focussing on low extents of cure—the most important region for the mould-filling stage in resin transfer moulding. A key advantage of the model is that it is not explicitly dependent on the extent of cure; therefore, the model can be used to predict the viscosity during cure

N Kiuna; C. J Lawrence; Q. P. V Fontana; P. D Lee; T Selerland; P. D. M Spelt

2002-01-01

470

Studies in the reaction-separation method for the preparation of barium chloride from barite using ion exchange  

SciTech Connect

The authors report the application of an ion-exchange process as a reaction-separation strategy for the preparation of barium chloride from barite ore and sodium chloride. Experimental studies were carried out to evaluate the process efficiency and purity/yield of barium chloride using a strong acid cation-exchange resin, Tulsion T-42. The effects of various process parameters such as concentration of barium sulfide and concentration of sodium chloride were investigated, and optimization of the experimental variables was attempted. The results indicate the developed strategy to be attractive and an alternative route to existing processes. The methodology developed has large potential for the inorganic chemical process industry in general.

Gokarn, A.N.; Gaikwad, A.G.; Phalak, C.A.; Bhandari, V.M. [National Chemical Lab., Pune (India). Chemical Engineering Div.] [National Chemical Lab., Pune (India). Chemical Engineering Div.

1999-06-01

471

NITRATE CONVERSION OF HB-LINE REILLEXTM HPQ RESIN  

SciTech Connect

Reillex{trademark} HPQ ion exchange resin is used by HB Line to remove plutonium from aqueous streams. Reillex{trademark} HPQ resin currently available from Vertellus Specialties LLC is a chloride ionic form, which can cause stress corrosion cracking in stainless steels. Therefore, HB Line Engineering requested that Savannah River National Laboratory (SRNL) convert resin from chloride form to nitrate form in the Engineering Development Laboratory (EDL). To perform this task, SRNL treated two batches of resin in 2012. The first batch of resin from Reilly Industries Batch 80302MA was initially treated at SRNL in 2001 to remove chloride. This batch of resin, nominally 30 liters, has been stored wet in carboys since that time until being retreated in 2012. The second batch of resin from Batch 23408 consisted of 50 kg of new resin purchased from Vertellus Specialties in 2012. Both batches were treated in a column designed to convert resin using downflow of 1.0 M sodium nitrate solution through the resin bed followed by rinsing with deionized water. Both batches were analyzed for chloride concentration, before and after treatment, using Neutron Activation Analysis (NAA). The resin specification [Werling, 2003] states the total chlorine and chloride concentration shall be less than 250 ppm. The resin condition for measuring this concentration is not specified; however, in service the resin would always be fully wet. Measurements in SRNL showed that changing from oven dry resin to fully wet resin, with liquid in the particle interstices but no supernatant, increases the total weight by a factor of at least three. Therefore, concentration of chlorine or chloride expressed as parts per million (ppm) decreases by a factor of three. Therefore, SRNL recommends measuring chlorine concentration on an oven dry basis, then dividing by three to estimate chloride concentration