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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 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

4

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2013 CFR

21 Food and Drugs 6 2013-04-01... Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... Acrylamide-acrylic acid resin....

2013-04-01

5

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2012 CFR

21 Food and Drugs 6 2012-04-01... Acrylamide-acrylic acid resin. 573.120 Section 573.120 Food and Drugs FOOD AND DRUG ADMINISTRATION...CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED... Acrylamide-acrylic acid resin....

2012-04-01

6

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

7

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

8

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

...2014-04-01 false Partial phosphoric acid esters of polyester resins. 175.260...Coatings § 175.260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified...

2014-04-01

9

Leaching of concrete admixtures containing thiocyanate and resin acids.  

PubMed

There is an increasing concern about the emission of pollutants during the construction and lifetime of buildings. The leaching of concrete admixtures containing thiocyanate and resin acids was studied using standard leaching tests and chemical analysis. Ecotoxicological risk was assessed for each admixture. Thiocyanate leaching from concrete, with a chlorine-free accelerating admixture, was determined by ion chromatography. Of the total amount of thiocyanate added, 6-8% was emitted within 30 d. The thiocyanate diffusion curve indicates a fast dissolution process from the surface layer, followed by a slower continuous diffusion process. Thiocyanate exhibits both acute and chronic toxicity, which makes it of immediate environmental concern. Resin acid leaching from concrete test specimens containing an admixture of air-entraining agents with tall oil was determined by solid-phase extraction, methylation, and GC/MS. Of added resin acids, 10% was emitted over 143 d. The leaching curves for the resin acids indicate a continuous diffusion that is proportional to the square root of time and follows Fick's first law of diffusion. The chemical composition of the resin acids in the leachate demonstrates degradation and rearrangement of the resin acids during diffusion. Resin acids emitted from concrete are of environmental concern because they are persistent and have the ability to bioaccumulate in aquatic organisms. PMID:11349293

Andersson, A C; Stromvall, A M

2001-02-15

10

Raman spectroscopic studies of acid dissociation in sulfonated polystyrene resins  

NASA Astrophysics Data System (ADS)

FT-Raman spectra of sulfonated polystyrene resins with varying levels of sulfonation from 9-97% have been recorded. Molecular markers of -SO 3H and -SO 3- moieties have been proposed and used to determine quantitatively the degree of dissociation of the acids as a function of total sulfonic acid and sulfonate concentrations. Comparison with the ethanesulfonic acid/water system has been made and it is concluded that the low-sulfonation and high-sulfonation resins closely resemble this molecular acid/water system, but that intermediate sulfonation specimens are dissociated some 18% less than the corresponding ethanesulfonic acid/water analogues. This is ascribed to the presence of hydrogen-bonded acid groups with water in the gel region of the resins which had been suggested in previous infrared spectroscopic measurements.

Edwards, H. G. M.; Brown, D. R.; Dale, J. R.; Plant, S.

2001-09-01

11

Biomimetic Remineralization of Resin-bonded Acid-etched Dentin  

PubMed Central

Degradation of denuded collagen within adhesive resin-infiltrated dentin is a pertinent problem in dentin bonding. A biomimetic remineralization scheme that incorporates non-classic crystallization pathways of fluidic amorphous nanoprecursors and mesoscopic transformation has been successful in remineralizing resin-free, acid-etched dentin, with evidence of intrafibrillar and interfibrillar remineralization. This study tested the hypothesis that biomimetic remineralization provides a means for remineralizing incompletely infiltrated resin-dentin interfaces created by etch-and-rinse adhesives. The remineralization medium consists of a Portland cement/simulated body fluid that includes polyacrylic acid and polyvinylphosphonic acid biomimetic analogs for amorphous calcium phosphate dimension regulation and collagen targeting. Both interfibrillar and intrafibrillar apatites became readily discernible within the hybrid layers after 2-4 months. In addition, intra-resin apatite clusters were deposited within the porosities of the adhesive resin matrices. The biomimetic remineralization scheme provides a proof-of-concept for the adoption of nanotechnology as an alternative strategy to extend the longevity of resin-dentin bonds. PMID:19734458

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

2009-01-01

12

Separation of resin acids from fatty acids in relation to environmental studies.  

PubMed

Kraft mills pulping coniferous wood species discharge to their receiving waters effluents containing mixed resin and fatty acids. To study the fish-toxic properties of these fractions it is desirable to be able to separate them without causing double bond isomerizations in the acid-labile resin acid fraction. A method is described using toluenesulphonic acid as catalyst under very mild conditions and four examples of its application are given. It was not possible to separate tall oil samples without a low degree of resin acid isomerization. PMID:1150822

Mahood, H W; Rogers, I H

1975-06-18

13

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

14

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

15

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

16

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

USGS Publications Warehouse

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

Aiken, G.R.

1979-01-01

17

Supporting Information Amino acids, amino acid derivatives, and resins were from Novabiochem. Gel filtration  

E-print Network

Supporting Information ­1­ Materials Amino acids, amino acid derivatives, and resins were from Analytical HPLC was performed with an Aligent C8 column or a Varian Dynamax C18 column with linear gradients with sinapinic acid (Fluka) as the matrix at the University of Wisconsin­Madison Biophysics Instrumentation

Raines, Ronald T.

18

Allergenic potential of abietic acid, colophony and pine resin-HA. Clinical and experimental studies.  

PubMed

Resin acids are considered to be the main allergens in colophony (rosin). Tall oils also contain resin acids and may then be potential sensitizers. A resin acid concentrate (pine resin-HA) together with Chinese colophony were included in our standard series and applied on 563 patients with contact dermatitis. Fourteen showed an isolated sensitivity to colophony and two to pine resin-HA. Six patients reacted to both test compounds. Guinea pig maximization tests (Magnusson & Kligman 1969) showed that pine resin-HA (2 series) was a grade I allergen, abietic acid a grade III allergen and colophony a grade IV allergen. The risk that the resin acids in tall oils would induce contact sensitivity to workers exposed to tall oil-containing products like cutting fluids and cleansing agents is considered to be minimal. PMID:7214893

Karlberg, A T; Boman, A; Wahlberg, J E

1980-12-01

19

Removal of dyes from water using crosslinked aminomethane sulfonic acid based resin.  

PubMed

A new polymeric resin with amino sulfonic acid pendant functions has been prepared for the extraction of acidic and basic dyes from water. Beaded polymer supports were prepared by suspension polymerization of vinyl benzyl chloride (0.9 mol) and ethylene glycol dimethacrylate (0.1 mol). The resulting copolymer beads were modified with amino methane sulfonic acid. The dye adsorption capacity of the resin was found as 0.16 g dye/g resin for ramazol black and 0.15 g dye/g resin for crystal violet. The pH depending measurements and dye sorption kinetics of the resin were also investigated. PMID:20401517

Kaner, Damla; Saraç, Ayfer; Senkal, Bahire Filiz

2010-08-01

20

Studies on structure and properties of CNSL novolac resins prepared with succinic acid catalyst  

Microsoft Academic Search

Cashew nut shell liquid (CNSL) was used to prepare a glass fabric laminate. Two fast curing model resins were prepared using\\u000a cardanol and formaldehyde in the presence of succinic acid catalyst. The resins possess ortho-ortho and ortho-para linkages.\\u000a The curing kinetics of the resins showed that the resin prepared with mole ratio 0·8 possesses good curing characteristics.\\u000a The IR spectra

K Sathiyalekshmi

1993-01-01

21

Synthesis and polymerization of a radiation curable hyperbranched resin based on epoxy functional fatty acids  

Microsoft Academic Search

A radiation curable resin has been synthesized from a hydroxy functional hyperbranched polyether onto which an epoxy functional fatty acid, vernolic acid, has been attached. The resin was cationically polymerized in presence of different amounts of vernolic acid methyl ester as a reactive diluent. The coating mixtures contained up to 30wt.% methyl ester and all formulations polymerized readily and formed

Johan Samuelsson; Per-Erik Sundell; Mats Johansson

2004-01-01

22

Surface and line-edge roughness in acid-breakable resin-based positive resist  

NASA Astrophysics Data System (ADS)

A positive chemical amplification resist based on acid-catalyzed fragmentation of acetal groups in its main-chain has been developed as a means for reducing line-edge roughness. The resist consists of an acid-generator, an acid-diffusion controller and an acid-breakable (AB) resin that is synthesized through a co-condensation reaction between polyphenol and aromatic multi-functional vinylether compound. The effects of the fractionation of AB resins on resin properties and line-edge roughness (LER) are evaluated. Although AB resins have wide molecular-weight distributions, the density of acetal groups in this AB resin is found to be almost constant except in the lower molecular-weight components. The resist with a fractionated resin from which such components removed provides the high resolution of 60-nm line-and-space (L/S) patterns with fairly low LER. AFM analysis shows the surface roughness (SR) for the resist with the fractionated resin is smaller than that for a resist using non-fractionated AB resin, and that the SR value is not altered throughout the range of exposure doses up to just below the beginning of dissolution. By using the fractionated AB resin, the AB resin-based resist (ABR) is capable of forming sub-100 nm L/S patterns with less than 5 nm of LER (3?).

Sakamizu, Toshio; Shiraishi, Hiroshi

2003-06-01

23

Recovery of lactic acid from simultaneous saccharification and fermentation media using anion exchange resins  

Microsoft Academic Search

The physicochemical properties (capacity, kinetics and selectivity) of the ion exchange resins Amberlite IRA900, IRA400, IRA96 and IRA67 were determined to evaluate their comparative suitability for lactic acid recovery. Both the kinetics of lactic acid sorption from aqueous solutions and the equilibrium were assessed using mathematical models, which provided a close interpretation of the experimental results. The best resins (Amberlite

A. B. Moldes; J. L. Alonso; J. C. Parajó

2003-01-01

24

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

Microsoft Academic Search

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

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

2010-01-01

25

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

26

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

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

Purification of chlorogenic acid in Flos Lonicerae with system of polar ordered resins  

Microsoft Academic Search

A system of polar ordered resins was established for purification of chlorogenic acid in Flos Lonicerae. It was composed of three reversed phase resins, AB-8, DM-130 and NKA-9, representative for their gradually increased polarity\\u000a and selectivity. A method of RP-HPLC was used for determination of chlorogenic acid. And the performance of adsorption and\\u000a desorption for chlorogenic acid with the system

Zhi-nan Xiang; Yu Zhan; Zheng-xiang Ning

2007-01-01

29

Properties of carbonized and converted uranium-loaded weak-acid resins  

Microsoft Academic Search

Weak-acid ion-exchange resins have been found to provide a practical method for fabricating uranium-containing HTGR fuel kernels. Two steps, thermal decomposition or carbonization and carbothermic reduction of UO or conversion, are required in the manufacture of these kernels. The property variations during carbonization of uranium-loaded weak-acid resin-derived fuel proceeds in a manner closely analogous to its thermogravimetric characteristics, particularly the

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

1977-01-01

30

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

SciTech Connect

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

Hendriksen, D.E.

1983-01-01

31

Synthesis, Characterization, and Applications of a New Ion Exchanger Tamarind 4-aminobenzoic Acid (TABA) Resin in Industrial Wastewater Treatment  

Microsoft Academic Search

Chromatographic column separations of toxic metal ions from industrial wastewater were achieved in acid media at optimized (Kd) values with a synthesized cation exchange TABA resin. The prepared TABA resin was characterized by FTIR, elemental, and thermogravimetric analysis. Studies of total ion exchange capacity, resin durability, and swelling were carried out. The distribution coefficient values of metal ions, viz Cu,

A. V. Singh; Naresh Kumar Sharma

2012-01-01

32

Potential of Presep(®) PolyChelate as a chelating resin: comparative study with some aminocarboxylic acid-type resins.  

PubMed

The potential of Presep(®) PolyChelate as a chelating resin was studied in detail. The chelating resin with extraction capacity for Cu of 0.30 mmol L(-1) could quantitatively extract Cd, Co, Cu, Fe, Mo, Ni, Pb, V, and Zn at pH 4 or 5.5; however, only very scant amounts of Na, K, Mg, and Ca were captured at pH levels below 7. The quantitative extraction could be achieved in 100 - 1000 mL of artificial seawater and at a flow rate of 3 - 30 mL min(-1). The performance of Presep(®) PolyChelate was compared to the other aminocarboxylic acid-type chelating resins, including Nobias Chelate-PA1, Chelex 100, Muromac B-1, Lewatit TP 207, and NTA Superflow, under the same conditions. The solid-phase extraction of the nine elements in the certified reference material (ES-L-1, ground water) and a commercially available table salt was also demonstrated. PMID:24212740

Kagaya, Shigehiro; Saeki, Yumi; Morishima, Daiki; Shirota, Riko; Kajiwara, Takehiro; Kato, Toshifumi; Gemmei-Ide, Makoto

2013-01-01

33

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

PubMed

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

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

1993-06-01

34

Evaluation of flowable resin composite surfaces eroded by acidic and alcoholic drinks.  

PubMed

The purpose of this study was to evaluate the morphological changes of the surfaces of flowable resins eroded by orange juice and alcohol drinks. The tested products were Beautifil Flow BF02 and BF10, Clearfil Majesty LV, Filtek Supreme XT Flowable Restorative, Unifil LoFlo Plus and Filtek Supreme. Filler percentages of flowable resins were calculated after the latter were incinerated at 750 degrees C. Specimens were shaped into a disk form with a diameter of 10 mm and a thickness of 1 mm. Morphological changes were evaluated for the following types of flowable resin surfaces: polished surface, surfaces eroded by 100% orange juice, wine and whisky. Filler percentages of the tested flowable resins ranged between 42 and 78%. Surface degradation was observed for the specimens immersed in acidic and alcoholic drinks, and it was thought that the lower the filler percentage, the greater was the surface degradation. Decomposition of the matrix resin and fallout of the fillers were observed in flowable resins that eroded with acidic and alcoholic drinks. PMID:18717176

Han, Linlin; Okamoto, Akira; Fukushima, Masayoshi; Okiji, Takashi

2008-05-01

35

Methylene crosslinked calix[6]arene hexacaarboxylic acid resin: a highly efficient solid phase extractant for decontamination of lead bearing effluents.  

PubMed

Calixarene-based cation exchange resin has been developed by methylene crosslinking of calix[6]arene hexacarboxylic acid derivative and the resin has been exploited for solid phase extraction of some toxic heavy metal ions. The selectivity order of the resin towards some metal ions follows the order Pb(II) > Cu(II)> Zn(II), Ni(II), Co(II). The maximum lead ion binding capacity of the resin was found to be 1.30 mmol g(-1) resin. The loaded lead was quantitatively eluted with dilute acid solution regenerating the resin. Mutual separation of Pb(II), Cu(II) and Zn(II) was achieved by using the column packed with the resin. PMID:21835544

Adhikari, Birendra Babu; Gurung, Manju; Kawakita, Hidetaka; Jumina; Ohto, Keisuke

2011-10-15

36

Acid-Breakable Resin-Based Chemical Amplification Positive Resist for Electron-Beam Mastering: Design and Lithographic Performance  

NASA Astrophysics Data System (ADS)

A positive chemical amplification resist based on acid-catalyzed fragmentation of acetal groups in its main chain has been developed as a means of reducing line-edge roughness. The resist consists of an acid generator, an acid-diffusion controller and an acid-breakable (AB) resin that is synthesized through a co-condensation reaction between polyphenol and aromatic multifunctional vinylether compound. The effects of the fractionation of AB resins on resin properties and line-edge roughness (LER) are evaluated. Although AB resins have wide molecular weight distributions, the density of acetal groups in this AB resin is found to be almost constant except in the lower molecular weight components. The resist with a fractionated resin from which such components are removed provides high-resolution patterns (70-nm-wide pit) with fairly low LER. AFM analysis shows that the surface roughness (SR) of the resist with the fractionated resin is smaller than that of a resist using nonfractionated AB resin, and that the SR value is not altered throughout the range of exposure doses up to just below the start of dissolution. By using the fractionated AB resin, the AB resin-based resist (ABR) is capable of forming sub-100 nm L/S patterns with less than 5 nm of LER (3?).

Sakamizu, Toshio; Shiraishi, Hiroshi

2004-07-01

37

Reaction of dicyclopentadiene with formic acid and chloroacetic acid with and without cation-exchange resins as catalysts  

Microsoft Academic Search

The uncatalysed and catalysed (with cation-exchange resin) esterification of formic acid and chloroacetic acid, with dicyclopentadiene (DCPD), i.e. 4,7-methano-3a,4,7,7a-tetrahydroindene, was carried out. The effect of various parameters, e.g. speed of agitation, catalyst loading, mole ratio of the reactants, temperature, concentration of formic acid in aqueous solutions were studied to optimise the reaction conditions. DCPD cam be quantitatively converted to the

Basudeb Saha; Man Mohan Sharma

1997-01-01

38

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

39

Modification of petroleum polymer resin from C9 fraction with maleic acid and its application to protecting treatment of wood  

Microsoft Academic Search

Modification of petroleum polymer resin with maleic acid is studied and changes in acid number, molecular weight and bromine\\u000a number of the forming product in time are determined. The modified petroleum polymer resin is shown useful for enhancing hydrophobic\\u000a properties of wood.

A. N. Chernaya; O. N. Filimonova; S. S. Nikulin

2007-01-01

40

Paal-Knorr Pyrrole Synthesis Using Recyclable Amberlite IR 120 Acidic Resin: A Green Approach  

Microsoft Academic Search

Amberlite IR 120 acidic resin, an age old polymer matrix, has been demonstrated as a catalyst for Paal-Knorr condensation of 2,5-hexadione with primary amines under solvent free conditions. This is an efficient, mild and green methodology for N-substituted pyrrole derivatives.

Aarti Devi; Shallu; M. L. Sharma; Jasvinder Singh

2012-01-01

41

Paal–Knorr Pyrrole Synthesis Using Recyclable Amberlite IR 120 Acidic Resin: A Green Approach  

Microsoft Academic Search

Amberlite IR 120 acidic resin, a polymer matrix, has been demonstrated as a catalyst for Paal-Knorr condensation of 2,5-hexadione with primary amines under solvent-free conditions. This is an efficient, mild, and green methodology for N-substituted pyrrole derivatives.

Aarti Devi; Shallu; M. L. Sharma; Jasvinder Singh

2012-01-01

42

The application of macroporous resins in the separation of licorice flavonoids and glycyrrhizic acid  

Microsoft Academic Search

Glycyrrhizic acid (GA) and licorice flavonoids (LF) are the two classes of bioactive components in licorice with known pharmacological effects. But long-term excessive intake of GA may cause sodium retention and hypertension. In this study, the performance and adsorption characteristics of four widely used macroporous resins for the separation of deglycyrrhizinated, flavonoids enriched licorice has been critically evaluated. The sorption

Boqiang Fu; Jie Liu; Huan Li; Lei Li; Frank S. C. Lee; Xiaoru Wang

2005-01-01

43

Reaction of 5-ethylidene-2-norbomene with formic acid: cation exchange resins as catalysts  

Microsoft Academic Search

The esterification of formic acid with ethylidene norbornene (ENB), i.e. 5-ethylidene bicyclo[2.2.1]hept 2-ene was carried out with and without cation exchange resins as catalysts. The effect of various parameters e.g. speed of agitation, catalyst loading, mole ratio of the reactants, temperature, concentration of formic acid in aqueous solutions were studied to optimise the reaction conditions; the reusability of catalysts was

Basudeb Saha

1998-01-01

44

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

SciTech Connect

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

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

1995-06-01

45

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

PubMed

The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic acids (pyromellitic, trimellitic, hemimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic, salicylic acids and phenol) was carried out using diluted sulfuric acid as the eluent. Silica-based cation-exchange resins (TSKgel SP-2SW and TSKgel CM-2SW) were very suitable for the ion-exclusion chromatographic separation of these benzenecarboxylic acids. Excellent simultaneous separation of these benzenecarboxylic acids was achieved on a TSKgel SP-2SW column (150 x 6 mm I.D.) in 17 min using a 2.5 mM sulfuric acid at pH 2.4 as the eluent. Polymethacrylate-based cation-exchange resins (TSKgel SP-5PW, TSKgel CM-5PW and TSKgel OA-Pak A) acted as advanced stationary phases for the ion-exclusion chromatographic separation of these C1-C7 aliphatic carboxylic acids. Excellent simultaneous separation of these C1-C7 acids was achieved on a TSKgel CM-5PW column (150 x 6 mm I.D.) in 32 min using a 0.05 mM sulfuric acid at pH 4.0 as the eluent. PMID:12830883

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

2003-05-16

46

Toxic effects of some conifer resin acids and tea tree oil on human epithelial and fibroblast cells  

Microsoft Academic Search

The present study was undertaken to assess and compare the in vitro cytotoxic effects of three resin acid analogues: dehydroabietic acid, podocarpic acid, O-methylpodocarpic acid; an essential oil from Australia (tea tree oil); and tapped oleoresin from Thailand, on human epithelial and fibroblast cells, using a quantitative neutral red spectrophotometric assay. All of the investigated compounds except for tea tree

Thor A. Söderberg; Anders Johansson; Rolf Gref

1996-01-01

47

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

PubMed

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

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

2006-01-01

48

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

49

Polyacrolein-isonicotinic acid hydrazone and polyacrylic acid-thiohydrazide resins-synthesis and sorption properties for precious and base metals  

Microsoft Academic Search

This investigation carries on previous studies on polyacrolein-styrene resins. Further attempts were made to convert the reactive aldehyde groups of the polymeric support to functional acrolein-isonicotinic acid hydrazone (P-NHZ) or acrylic acid-thiohydrazide derivatives (P-THZD). The conditions of synthesis and the basic sorption and desorption properties of the polymers synthesized are described. For gold and platinum group metals the resins show

Xiao-Peng Ge; Bao-Wen Zhang; Manfred Grote

1998-01-01

50

Application of polyacrolein–isonicotinic acid hydrazone resin for the separation and concentration of Pd and Pt in road dust  

Microsoft Academic Search

A chelating resin containing isonicotinic acid hydrazone as functional group (P-NHZ) was synthesized and characterized through IR spectra and elemental analysis. The potential of this resin for the separation and preconcentration of Pd and Pt was extensively investigated. Efforts were also made for its use in the determination of Pd and Pt by Q-ICP-MS. The interferences from YO+ during Pd

Xiaopeng Ge; Iris Wendler; Peter Schramel; Antonius Kettrup

2004-01-01

51

Evaluation of hydrogenated resin acids as molecular markers for tire-wear debris in urban environments.  

PubMed

To propose new molecular markers for tire-wear emissions, four dihydroresin acids, that is, 8-isopimaren-18-oic acid (I), 8-pimaren-18-oic acid (II), 13?(H)-abieten-18-oic acid (III), and 13?(H)-abiet-8-en-18-oic acid (IV), were identified and investigated for source specificities, distributions, and environmental stabilities. The absence of I-IV in natural sources and the linear correlations between dihydroresin acids with different skeletons in tires and in environmental samples demonstrated that I-IV are specific markers for synthetic rubbers. The ratio of III + IV to the sum of III + IV plus abietic acid showed the resin acids distribution between different environmental compartments receiving contributions from traffic and natural sources. The physicochemical properties and results of photolysis experiments suggested that I-IV can set lower limits for tire-wear contributions to environmental loads of particulate matter (PM) and polycyclic aromatic hydrocarbons with molecular weight ?202. By comparing III + IV concentrations or (III+IV)/pyrene or (III+IV)/benzo[a]pyrene ratios in tires and those in environmental matrices, the contributions of tire-wear emissions to PM, pyrene, and benzo[a]pyrene were estimated to be 0.68 ± 0.54%, 6.9 ± 4.8%, and 0.37 ± 0.18% in roadside PM and 0.83 ± 0.21%, 0.88 ± 0.52%, and 0.08 ± 0.06% in rooftop PM. PMID:22008013

Kumata, Hidetoshi; Mori, Mika; Takahashi, Sho; Takamiya, Shohei; Tsuzuki, Mikio; Uchida, Tatsuya; Fujiwara, Kitao

2011-12-01

52

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

PubMed

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

Hashmi, Sara M; Firoozabadi, Abbas

2013-03-15

53

Contact allergy due to colophony (VI). The sensitizing capacity of minor resin acids and 7 commercial modified-colophony products.  

PubMed

3 minor resin acids and 7 commercial modified-colophony products of different origins were studied by experimental sensitization by means of a modified FCA method. All 3 resin acids were almost negative. The commercial products gave different results. While the maleic-modified product of Greek origin showed a strong sensitizing power, the fumaric-modified, terpene-phenol-modified and a disproportioned rosin were only moderate. A remarkable difference was obtained with the Swedish and Finnish tall oil rosins, which, in contrast to the previously studied French product, exhibited only a weak sensitizing capacity. PMID:2209010

Hausen, B M; Hessling, C

1990-08-01

54

Analysis of pentacyclic triterpenic acids from frankincense gum resins and related phytopharmaceuticals by high-performance liquid chromatography. Identification of lupeolic acid, a novel pentacyclic triterpene  

Microsoft Academic Search

An HPLC gradient method with photodiode array detection was developed for the simultaneous analysis of 12 different pentacyclic triterpenic acids in Indian and African frankincense gum resins as well as in related phytopharmaceuticals. The triterpenic acids were obtained by an exhaustive extraction procedure. Identification of the compounds was based on retention times, UV-spectra and add on technique with standards isolated

Berthold Büchele; Waltraud Zugmaier; Thomas Simmet

2003-01-01

55

Stability of two resin combinations used as sealants against toothbrush abrasion and acid challenge in vitro.  

PubMed

Abstract Objective. To test the stability of two conventional adhesives when combined with a low-viscosity caries infiltrant used for sealing sound enamel against toothbrush abrasion and acid challenge in vitro. Materials and methods. Bovine enamel discs (Ø = 3 mm) randomly assigned to three groups (n = 10/group) were etched with 37% phosphoric acid for 30 s and treated with resins of different monomer contents forming three test groups: (1) Untreated specimens (Control); (2) Infiltrant (Icon, DMG) + conventional enamel bonding adhesive (Heliobond, Ivoclar Vivadent); and (3) Infiltrant + conventional orthodontic adhesive (Transbond XT Primer, 3M Unitek). All specimens were immersed in hydrochloric acid (pH 2.6) for up to 9 days, during which they were exposed to 1825 toothbrush-strokes per day. Calcium dissolution was assessed using Arsenazo III method at 24-h intervals. Data were analyzed by Kruskal-Wallis and Wilcoxon signed ranks tests. Results. Cumulative calcium dissolution for the untreated specimens (39.75 ± 7.32 ?mol/ml) exceeded the sealed groups (Icon + Heliobond: 23.44 ± 7.03 ?mol/ml; Icon + Transbond XT Primer: 22.17 ± 5.34 ?mol/ml). Untreated specimens presented a relatively constant calcium dissolution rate throughout the experimental period, whereas the sealed groups presented a gradual increase indicating weakening of the seal by toothbrush abrasion. Both sealed groups presented significantly lower daily calcium dissolution at all time points compared to the control, except for Group 2 on the last measurement day. Conclusions. Low-viscosity caries infiltrant application on sound enamel prior to conventional resin application provided a protective effect against enamel demineralization, but this effect was not stable when challenged mechanically by toothbrush abrasion. PMID:24850503

Yetkiner, Enver; Wegehaupt, Florian Just; Attin, Rengin; Wiegand, Annette; Attin, Thomas

2014-11-01

56

Sorption of dicyanoaurate anions by novel resins containing N,N{prime}-substituted diamides of malonic acid  

SciTech Connect

Two novel ion-exchange/coordinating resins have been synthesized and used in the sorption of dicyanoaurate anions, Au(CN){sub 2}{sup {minus}}, from aqueous solution from their mixtures with Fe(III) cyano complexes, Ag(I) cyano complexes, Zn(II) cyano complexes, Fe(II) cyano complexes, Cu(II) cyano complexes, and from solutions containing all of the above species. It has been found that Resin 1 containing the N,N{prime}-substituted amide of malonic acid with terminal guanidyl groups is able to remove ca. 10 mg Au/g, and Resin 2 containing the N,N{prime}-substituted amide of malonic acid with terminal imidazole groups removes ca. 13 mg Au/g from the above solutions when there is an initial concentration of 5.08 mg Au/dm{sup 3}. Resin 1 is selective toward gold over all metals but Fe(II). Resin 2 is more selective, and when sorption is carried out from the solution formulated with all the metals displays the following selectivity coefficients: of gold over Fe(II) + Fe(III), +{infinity}; of gold over Ag(I), +{infinity}; of gold over Zn(II), 3.79; and of gold over Cu(II), 2.81.

Trochimczuk, A.W.; Kolarz, B.N.; Jermakowicz-Bartkowiak, D.; Apostoluk, W. [Wroclaw Univ. of Technology (Poland)] [Wroclaw Univ. of Technology (Poland)

1999-08-01

57

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

58

Determination of thyroid hormones in serum by means of a cation exchange resin and chloric acid digestion  

Microsoft Academic Search

A simple and specific method for the determination of iodoamino acids (IAA) and hormonal iodine (HI) in serum is presented. 0.5 ml serum is allowed to run through a small column with a cation exchange resin. To isolate IAA, the column is washed with water and eluted with ammonia. To isolate HI, the column is washed with borate buffer, then

E. T. Backer; T. H. J. Postmes; J. D. Wiener

1967-01-01

59

Long-term impact of acid resin waste deposits on soil quality of forest areas II. Biological indicators.  

PubMed

In this study, we evaluated the effects of two acid resin deposits on the soil microbiota of forest areas by means of biomass, microbial activity-related estimations and simple biological ratios. The determinations carried out included: total DNA yield, basal respiration, intracellular enzyme activities (dehydrogenase and catalase) and extracellular enzyme activities involved in the cycles of C (beta-glucosidase and chitinase), N (protease) and P (acid-phosphatase). The calculated ratios were: total DNA/total N; basal respiration/total DNA; dehydrogenase/total DNA and catalase/total DNA. Total DNA yield was used to estimate soil microbial biomass. Results showed that microbial biomass and activity were severely inhibited in the deposits, whilst resin effects on contaminated zones were variable and site-dependant. Correlation analysis showed no clear effect of contaminants on biomass and activities outside the deposits, but a strong interdependence with natural organic matter related parameters such as total N. In contrast, by using simple ratios we could detect more stressful conditions in terms of organic matter turnover and basal metabolism in contaminated areas compared to their uncontaminated counterparts. These results stress that developed ecosystems such as forests can buffer the effects of pollutants and preserve high functionality via natural attenuation mechanisms, but also that acid resins can be toxic to biological targets negatively affecting soil dynamics. Acid resin deposits can therefore act as contaminant sources adversely altering soil processes and reducing the environmental quality of affected areas despite the solid nature of these wastes. PMID:18768212

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

2008-11-15

60

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

E-print Network

on asphaltenes, including the effect of petroleum fluid composition. For instance, resins, naturally amphiphilic investigations into low-dosage asphaltene inhibitors used a selection of amphiphilic molecules with known structure in an effort to mimic resins, naturally-occuring petroleum amphiphiles [1]. Resins

Firoozabadi, Abbas

61

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

62

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

PubMed Central

Background Besides well-established roles of bile acids (BA) in dietary lipid absorption and cholesterol homeostasis, it has recently become clear that BA is also a biological signaling molecule. We have shown that strategies aimed at activating TGR5 by increasing the BA pool size with BA administration may constitute a significant therapeutic advance to combat the metabolic syndrome and suggest that such strategies are worth testing in a clinical setting. Bile acid binding resin (BABR) is known not only to reduce serum cholesterol levels but also to improve glucose tolerance and insulin resistance in animal models and humans. However, the mechanisms by which BABR affects glucose homeostasis have not been established. We investigated how BABR affects glycemic control in diet-induced obesity models. Methods and Findings We evaluated the metabolic effect of BABR by administrating colestimide to animal models for the metabolic syndrome. Administration of BABR increased energy expenditure, translating into significant weight reduction and insulin sensitization. The metabolic effects of BABR coincide with activation of cholesterol and BA synthesis in liver and thermogenesis in brown adipose tissue. Interestingly, these effects of BABR occur despite normal food intake and triglyceride absorption. Administration of BABR and BA had similar effects on BA composition and thermogenesis, suggesting that they both are mediated via TGR5 activation. Conclusion Our data hence suggest that BABR could be useful for the management of the impaired glucose tolerance of the metabolic syndrome, since they not only lower cholesterol levels, but also reduce obesity and improve insulin resistance. PMID:22952571

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

2012-01-01

63

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

Microsoft Academic Search

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

Jiyun Feng; Xijun Hu; Po Lock Yue

2004-01-01

64

Resin acid conversion with CYP105A1: an enzyme with potential for the production of pharmaceutically relevant diterpenoids.  

PubMed

Cytochrome P450s are very versatile enzymes with great potential for biotechnological applications because of their ability to oxidize unactivated C?H bonds. CYP105A1 from Streptomyces griseolus was first described as a herbicide-inducible sulfonylurea hydroxylase, but it is also able to convert other substrates such as vitamin D(3) . To extend the substrate pool of this interesting enzyme further, we screened a small diterpenoid compound library and were able to show the conversion of several resin acids. Binding of abietic acid, dehydroabietic acid, and isopimaric acid to the active site was assayed, and V(max) and K(m) values were calculated. The products were analyzed by NMR spectroscopy and identified as 15-hydroxyabietic acid, 15-hydroxydehydroabietic acid, and 15,16-epoxyisopimaric acid. As the observed products are difficult to obtain by chemical synthesis, CYP105A1 has proved to be a promising candidate for biotechnological applications that combine bioconversion and chemical synthesis to obtain functionalized resin acids. PMID:23371760

Janocha, Simon; Zapp, Josef; Hutter, Michael; Kleser, Michael; Bohlmann, Jörg; Bernhardt, Rita

2013-03-01

65

Adhesion of resin composite to hydrofluoric acid-exposed enamel and dentin in repair protocols.  

PubMed

Intraoral repairs of ceramic fixed-dental-prostheses (FDP) often include cervical recessions that require pretreatment of the exposed tooth surfaces either before or after the ceramic is conditioned with hydrofluoric (HF) acid gel. The sequence of repair protocol may cross-contaminate the exposed etched enamel or dentin surfaces during the application or rinsing process and thereby affect the adhesion. This study evaluated the influence of HF acid gel with two concentrations on bond strengths of composite to enamel and dentin. Human third molars (N=100, n=10 per group) with similar sizes were selected and randomly divided into 10 groups. Flat surfaces of enamel and dentin were created by wet ground finishing. Before or after the enamel (E) or dentin (D) was conditioned with phosphoric acid (P), substrate surfaces were conditioned with either 9.5% HF (HF(9.5)) or 5% HF (HF(5)). Subsequently, a bonding agent (B) was applied. The experimental groups by conditioning sequence were as follows where the first letter of the group abbreviation represents the substrate (E or D) followed by the acid type and concentration: group 1 (EPHF(9.5)), group 2 (EPHF(5)), group 3 (EHF(9.5)P), group 4 (EHF(5)P), group 5 (DPHF(9.5)), group 6 (DPHF(5)), group 7 (DHF(9.5)P), and group 8 (DHF(5)P). Group 9 (EPB) and group 10 (DPB) acted as the control groups. Repair resin was adhered incrementally onto the conditioned enamel and dentin in polyethylene molds. Each layer was photo-polymerized for 40 seconds. All specimens were thermocycled (×1000, 5°-55°C) and subjected to shear test (universal testing machine, 1 mm/min). Specimens that debonded during thermocycling were considered as 0 MPa. The bond strength data were analyzed using Kruskal-Wallis test and failure types using the chi-square test (?=0.05). Overall, the bond results (MPa) were lower on dentin than on enamel (p<0.01). EPB (25.6 ± 6.6) and DPB (20.2 ± 4.9) control groups showed significantly higher results than those of other groups (p<0.05). While higher mean bond strengths were obtained in group 1 (EPHF(9.5)) (11.5 ± 2.1) and group 2 (EPHF(5)) (7.3 ± 0.6), lower results were obtained when HF acid gels were applied prior to phosphoric acid (EHF(9.5)P: 5.0 ± 1.1, EHF(5)P: 3.6 ± 0.1) (p<0.05). On dentin, the results were the lowest in group 8 (DHF(5)P: 1.5 ± 1.6), being significantly lower than those of group 5 (DPHF(9.5)) (p<0.05). Scanning electron microscope (SEM) images revealed predominantly mixed failures with less than half of the composite left on both enamel and dentin surfaces (64 out of 80) (p<0.05), indicating that in general, adhesion was not ideal. Contamination of the enamel or dentin surfaces with HF acid gel impairs the bond strength of composites. Considering both the bond strength results and failure types, when dental tissues are to be repaired next to ceramic, application of phosphoric acid before HF acid gel application can be recommended. HF acid gel concentration did not influence the results except on enamel. PMID:21859315

Saracoglu, A; Ozcan, M; Kumbuloglu, O; Turkun, M

2011-01-01

66

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

67

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

PubMed

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

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

2014-05-01

68

Synthesis and characterization of abietadiene, levopimaradiene, palustradiene, and neoabietadiene: hydrocarbon precursors of the abietane diterpene resin acids  

Microsoft Academic Search

The abietane diterpenes—abietadiene, levopimaradiene, palustradiene, and neoabietadiene (1b–4b)—were prepared from the corresponding resin acids by diazomethane esterifications, LiAlH4 reductions, tosylations, and Zn\\/NaI reductions. Abietadiene was also obtained less efficiently by catechol borane reduction of abietadienal tosylhydrazone and Li\\/NH3 reduction of its 18-phenylthio derivative. These conjugated dienes were characterized by chromatographic properties (HPLC, TLC, GC), MS fragmentation patterns, optical rotations, and

Hyung-Jae Lee; Matthew M. Ravn; Robert M. Coates

2001-01-01

69

UPTAKE OF METAL IONS BY A NEW CHELATING ION-EXCHANGE RESIN. PART 2: ACID DEPENDENCIES OF TRANSITION AND POST-TRANSITION METAL IONS  

Microsoft Academic Search

Diphonixis a new dual-mechanism polyfunctional resin containing sulfonic and gem-diphosphonic acid groups. In Part 1 of this series the effectiveness of Diphonix in removing actinide ions from very acidic solutions was demonstrated. In this paper we report on the uptake of various transition and post-transition metal ions with Diphonix and two other resins for comparison. The results show that Diphonix

R. Chiarizia; E. P. Horwitz; R. C. Gatrone; S. D. Alexandratos; A. Q. Trochimczuk; D. W. Crick

1993-01-01

70

The erosion kinetics of conventional and resin-modified glass-ionomer luting cements in acidic buffer solutions.  

PubMed

This study investigated the erosion kinetics of conventional and resin-modified glass-ionomer luting cements in acidic buffer solutions as a function of time. Disc shaped specimens were prepared from conventional (Ketac-Cem: KTC) and resin-modified glass ionomer cements (Fuji Plus: FP) and immersed in three acidic buffer solutions (0.01 M) namely, acetic acid/sodium acetate (AA(B)), lactic acid/sodium lactate (LA(B)) and citric acid/sodium citrate (CA(B)) with a constant pH of 4.1 and stored for 1, 8, 24, 48, 80, 120 and 168 h. F concentration was determined using ion-specific electrode. Si, Ca and Al concentrations were determined by atomic absorption spectroscopy. Ca, Al, Si and F solubility rates in both FP and KTC were the highest in CA(B) solution. The erosion rates of both FP and KTC in all buffer solutions increased as a function of immersion time. The amount of F eluted from FP was more than that of KTC. The total amount of elements released from FP was less than KTC in all solutions. PMID:23207217

Hazar-Yoruc, Binnaz; Bavbek, Andac Barkin; Özcan, Mutlu

2012-01-01

71

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

72

Chemical evidence for archaeological frankincense: Boswellic acids and their derivatives in solvent soluble and insoluble fractions of resin-like materials  

Microsoft Academic Search

?-Boswellic acid (3?-hydroxyolean-12-en-24-oic acid) and ?-boswellic acid (3?-hydroxyurs-12-en-24-oic acid) and their acetates were identified in the solvent soluble fraction of samples of amorphous resin-like materials recovered from excavations at Qasr Ibrîm (Egyptian Nubia). The complementary 24-noroleana-3,12-diene and 24-norursa-3,12-diene were identified in pyrolysates of the residues where they were produced from the ?- and ?-boswellic acid and their acetates.

Pim F. van Bergen; Torren M. Peakman; Elizabeth C. Leigh-Firbank; Richard P. Evershed

1997-01-01

73

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

74

Study on the Flame-retardance and Thermal Stability of the Acid Anhydride-cured Epoxy Resin Flame-retarded by Triphenyl Phosphate and Hydrated Alumina  

Microsoft Academic Search

The effect of hydrated alumina and triphenyl phosphate on the flame-retardance and thermal stability of the acid anhydride-cured epoxy resin was studied by thermogravimetry and limiting oxygen index determination. The results show that both the hydrated alumina and triphenyl phosphate act as flame-retardants for epoxy resin in gas phase and display condensed phase flame-retardant synergism when they are used together.

Weidong Xiao; Peixin He; Gaoping Hu; Benqiao He

2001-01-01

75

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

76

Fatty and resin acid analysis in tall oil products via supercritical fluid extraction-supercritical fluid reaction using enzymatic catalysis.  

PubMed

Supercritical fluid extraction (SFE) is combined with supercritical fluid reaction (SFR) in an analytical mode to assess tall oil products for their fatty or resin acid content or both. The SFR consists of an inline enzymatically catalyzed reaction in which a lipase transesterifies specific lipids with methanol. The SFE-SFR sequence is conducted employing commercially available extractors using supported lipases in the extraction cell to form methyl esters. In this study, six different commercially available lipases are screened for activity. The SFE-SFR extracts are analyzed by capillary gas chromatography and supercritical fluid chromatography and then compared with tall oil products derivatized by conventional chemical derivatization techniques. PMID:11471988

Taylor, S L; King, J W

2001-07-01

77

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

SciTech Connect

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

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

1987-02-01

78

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

79

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

80

Complexation behavior of mono- and disaccharides by the vinylbenzeneboronic acid-divinylbenzene copolymer resins packed in a high-performance liquid chromatographic column.  

PubMed

Using an HPLC column packed with monodispersed vinylbenzeneboronic acid-divinylbenzene (V-D) copolymer resins, the elution behaviors of the mono- and disaccharides were studied under different pH mobile phases. The monodispersed V-D copolymer resins were prepared by the copolymerization of 4-vinylbenzeneboronic acid and divinylbenzene in the presence of template silica gel particles (particle size: 5 microm; pore size: 10 nm), followed by dissolution of the template silica gel using a NaOH solution. Similarly, styrene-divinylbenzene (S-D) copolymer resins as the control resins were also synthesized. The transmission electron micrographs of these polymer resins revealed a good monodispersity. The complexation behavior of the saccharides was evaluated by comparison of the peak area eluted through the V-D column for that through the S-D column. Four aldopentoses (D-ribose, D-arabinose, D-xylose, and D-lyxose) and four aldohexoses (D-glucose, D-mannose, D-galactose, and D-talose) were retained completely at pH 11.9. Especially, ribose and talose were totally retained even under acidic and neutral conditions. For the disaccharides, unlike sucrose and maltose, palatinose was completely retained in basic mobile phases. PMID:19362721

Kitahara, Kei-Ichi; Noguchi, Yuji; Itoh, Satoshi; Chiba, Nobunao; Tohyama, Tasuku; Nagashima, Kunio; Hanada, Takako; Yoshihama, Isao; Arai, Sadao

2009-10-30

81

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

82

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

83

Variability and Determinants of Wood Dust and Resin Acid Exposure during Wood Pellet Production: Measurement Strategies and Bias in Assessing Exposure-Response Relationships  

Microsoft Academic Search

Production of wood pellets is a relatively new and expanding industry in which the exposure profiles differ from those in other wood-processing industries like carpentries and sawmills where there are lower levels of wood dust. Sixty-eight personal exposure measurements of wood dust (inhalable and total dust) and resin acids were collected for 44 participants at four produc- tion plants located

KATJA HAGSTROM; CECILIA LUNDHOLM; KARE ERIKSSON; INGRID LILJELIND

2008-01-01

84

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

85

Synthesis of multifunctional Ag@Au@phenol formaldehyde resin particles loaded with folic acids for photothermal therapy.  

PubMed

Multifunctional Ag@Au@ phenol formaldehyde resin (PFR) particles loaded with folic acids (FA) have been designed for killing tumor cells through photothermy conversion under the irradiation of near-infrared (NIR) light. Possessing the virtue of good fluorescence, low toxicity, and good targeting, the nanocomposite consists of an Ag core, an Au layer, a PFR shell, and folic acids on the PFR shell. The Ag@PFR core-shell structure can be prepared with a simple hydrothermal method after preheating. We then filled the PFR shell with a layer of Au by heating and modified the shell with polyelectrolyte to change its surface charge state. To capture tumor cells actively, FA molecules were attached onto the surface of the Ag@Au@PFR particles in the presence of 1-ethyl-3-(3-dimethly aminopropyl) carbodiimide (EDAC) and N-hydroxysuccinimide (NHS). Owing to the excellent property of Au NPs and Ag NPs as photothermal conversion agents, the Ag@Au@ PFR@FA particles can be utilized to kill tumor cells when exposed to NIR light. PMID:22744779

Yang, Ping; Xu, Qi-Zhi; Jin, Sheng-Yu; Lu, Yang; Zhao, Yang; Yu, Shu-Hong

2012-07-23

86

Ion-exclusion chromatographic behavior of aliphatic carboxylic acids and benzenecarboxylic acids on a sulfonated styrene--divinylbenzene co-polymer resin column with sulfuric acid containing various alcohols as eluent.  

PubMed

The addition of C1-C7 alcohols (methanol, ethanol, propanol, butanol, heptanol, hexanol and heptanol) to dilute sulfuric acid as eluent in ion-exclusion chromatography using a highly sulfonated styrene-divinylbenzene co-polymer resin (TSKgel SCX) in the H+ form as the stationary phase was carried out for the simultaneous separations of both (a) C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, 2-methylvaleric, isocaproic, caproic, 2,2-dimethyl-n-valeric, 2-methylhexanoic, 5-methylhexanoic and heptanoic acids) and (b) benzenecarboxylic acids (pyromellitic, hemimellitic, trimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic and salicylic acids and phenol). Heptanol was the most effective modifier in ion-exclusion chromatography for the improvement of peak shapes and a reduction in retention volumes for higher aliphatic carboxylic acids and benzenecarboxylic acids. Excellent simultaneous separation and relatively highly sensitive conductimetric detection for these C1-C7 aliphatic carboxylic acids were achieved on the TSKgel SCX column (150 x 6 mm I.D.) in 30 min using 0.5 mM sulfuric acid containing 0.025% heptanol as eluent. Excellent simultaneous separation and highly sensitive UV detection at 200 nm for these benzenecarboxylic acids were also achieved on the TSKgel SCX column in 30 min using 5 mM sulfuric acid containing 0.075% heptanol as eluent. PMID:12830881

Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi

2003-05-16

87

Efficiency of macroporous poly(vinylphosphoramidic acid) resin adsorbing of selected elements and determination of trace dysprosium, holmium, erbium, and ytterbium in waste water by inductively coupled plasma optical emission spectrometry  

SciTech Connect

A macroporous poly(vinylphosphoramidic acid) resin is synthesized through the reaction of macroporous poly(vinylethylenediamine) resin with formaldehyde and phosphorus acid. The adsorption efficiency of the resin to selected elements is determined. An ICP-OES method has been established for the resin enrichment and separation of trace Dy, Ho, Er and Yb ions in waste water. The ability of the Na-form resin to adsorb Dy, Ho, Er, and Yb ions is far better than the H-form resin. The IR spectra of the resin before and after adsorbing Dy are shown. The mechanism of resin adsorption of Dy is explored. The results of resin enriched waste water analysis from a smelter plant are 31.0 ng/ml for dy, 41.1 ng/ml for Hl, 20.6 ng/ml for Er and 20.2 ng/ml for Yb ions. The recovery of standard additions of Dy, Ho, Er, and Yb to the waste water is in the range of 97.0-98.5%.

Zhan Guangyao; Su Zhixing; Lou Xingyin; Chang Xijun (Lanzhou Univ., Gansu (China))

1992-03-01

88

Induction of EROD Activity and Genotoxic Effects by Polycyclic Aromatic Hydrocarbons and Resin Acids on the Juvenile Eel ( Anguilla anguillaL.)  

Microsoft Academic Search

The purpose of this research is the study of total ethoxyresorufinO-deethylase (EROD) activity and erythrocytic nuclear abnormalities (NA) induction by polycyclic aromatic hydrocarbons (PAHs) and resin acids (RAs) on the juvenile eelAnguilla anguillaL. Juvenile eels were exposed, during 3 days, to the same molar concentration range (0, 0.1, 0.3, 0.9, and 2.7 ?M) of ?-naphthoflavone (BNF) and benzo[a]pyrene (BP)—PAHs—and abietic

M. Pacheco; M. A. Santos

1997-01-01

89

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

Microsoft Academic Search

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

A Latorre; A Rigol; S Lacorte; D Barceló

2003-01-01

90

Disinfecting the acrylic resin plate using electrolyzed acid water and 2% glutaraldehyde: a comparative microbiological study  

Microsoft Academic Search

Marked bactericidal activity of the electrolyzed acid water (EAW) and its less undesirable effects on biological tissues and\\u000a the environment has been successfully utilized in dental practice. A review of literature reveals that not many studies have\\u000a been performed to determine the disinfection effect of EAW on heat cured acrylic denture bases. The objective of the study\\u000a is to determine

K. R. Jnanadev; C. L. Satish Babu; S. Shilpa Shetty; G. P. Surendra Kumar; H. S. Sheetal

2011-01-01

91

High-performance bio-based bismaleimide resins using succinic acid and eugenol  

Microsoft Academic Search

Biseugenyl succinate (BEUS) and bis(4-maleimidephenyl) succinate (BMIS) were synthesized by the reaction of succinic acid (SA) with eugenol and the reaction of succinyl chloride with 4-hydroxyphenylmaleimide, respectively. A gelled mixture of BEUS and BMIS at a molar ratio of 1\\/1, 1\\/2 or 1\\/3 at 200 °C was compression-molded at 230 °C for 1 h to produce a cured BEUS\\/BMIS product.

Mitsuhiro Shibata; Naozumi Teramoto; Toshiaki Shimasaki; Megumi Ogihara

2011-01-01

92

Using of chelating resin to study the kinetic desorption of Eu(III) from humic acid-Al 2O 3 colloid surfaces  

NASA Astrophysics Data System (ADS)

The association of organic-inorganic colloid-borne trace elements was investigated. Radionuclide 152+154Eu(III) was chosen as a representative and chemical homologue for trivalent lanthanide and actinide ions present in radioactive nuclear waste. Effect of pH and contact time of organic-inorganic/Eu(III) on the kinetic dissociation of Eu(III) from HA-Al 2O 3 colloids was studied. The kinetic desorption behavior of sorbed 152+154Eu(III) from humic acid-?-Al 2O 3 colloids was studied at pH values of 4.5 ± 0.2, 5.3 ± 0.2 and 6.5 ± 0.2, respectively, by the addition of the chelating resin. The experimental results suggest that the fractions of irreversible sorption of radionuclide 152+154Eu(III) to HA-Al 2O 3 colloids increase with increasing pH values, and are independent of aging time. At least two different species, "weak" and "strong" dissociation fractions, are required to simulate the kinetic desorption of 152+154Eu(III) from HA-Al 2O 3 colloids. The species of Eu(III) sorbed on HA-Al 2O 3 colloids move from "weak" sites to "strong" sites with increasing aging time, whereas the fractions of irreversible sorption are independent of aging time. The results are important for the evaluation of radionuclides' behavior in the environment.

Wang, Xiangke; Zhou, Xiang; Du, Jinzhou; Hu, Wenping; Chen, Changlun; Chen, Yixue

2006-01-01

93

Multielemental elution behavior of metal ions adsorbed on iminodiacetic acid chelating resin by using hydrogen peroxide as an eluent.  

PubMed

In the present work, we investigated the multielemental elution behavior of metal ions absorbed on iminodiacetic acid (IDA) chelating resin by using hydrogen peroxide (H(2)O(2)) as an eluent. As a result, V(V), Mo(VI), W(VI), Nb(V) and Ta(V) were efficiently eluted by H(2)O(2). In contrast, other metal ions were rarely recovered. The oxidation states of V(V), Mo(VI), and W(VI) were not changed through the H(2)O(2) eluting process, checked by X-ray photoelectron analysis. In addition, the UV-vis adsorption spectra and IR spectra of V(V), Mo(VI) and W(VI) in the H(2)O(2) eluent suggested the formation of metal-peroxo complexes through H(2)O(2) elution. The desorption of these metal ions from IDA functional groups is explained in term of destabilization along with the coordination of peroxo-ligands to the V(V)-, Mo(VI)- and W(VI)-IDA complexes, and a decrease in the adsorption capacity by electrostatic repulsion between dissociated carboxylic groups of IDA and the oxoanions in the neutral pH shown in 30 wt% H(2)O(2). When this method was applied to the selective separation of V(V), Mo(VI) and W(VI) from other metals in an acid soluble fraction of fly-ash, 83.4 ± 2.5% of V(V), 88.1 ± 3.3% of Mo(VI), and 69.3 ± 5.4% of W(VI) were recovered in a 30 wt% H(2)O(2) eluent. PMID:22687925

Yabutani, Tomoki; Sumi, Hidehiko; Nakamura, Takamasa; Akatsuki, Shinsuke; Thuy, Le Thi Xuan

2012-01-01

94

Surface chemical modification on hyper-cross-linked resin by hydrophilic carbonyl and hydroxyl groups to be employed as a polymeric adsorbent for adsorption of p-aminobenzoic acid from aqueous solution  

Microsoft Academic Search

In this study, a novel hyper-cross-linked HJ-Y10 resin was synthesized and its adsorption behaviors for p-aminobenzoic acid were investigated from aqueous solution. The results indicated that the skeleton surface of HJ-Y10 resin was modified by formaldehyde carbonyl, quinone carbonyl and phenolic hydroxyl groups, the unadjusted p-aminobenzoic acid solution was favorable for the adsorption, the isotherms could be fitted by Langmuir

Xiaomei Wang; Jianhan Huang; Kelong Huang

2010-01-01

95

Effect of hybridization on bond strength and adhesive interface after acid-base challenge using 4-META/MMA-TBB resin.  

PubMed

The purposes of this study were twofold, namely to evaluate: (1) the effect of hybridization on microtensile bond strength (microTBS) to dentin, and (2) the ultrastructure of the dentin-adhesive interface with 4-META/MMA-TBB resin after acid-base challenge. Dentin surfaces, which received no treatment (NT), 65% phosphoric acid (PA), or 10% citric acid-3% ferric chloride (10-3), were bonded with a 4-META/MMA-TBB resin. To evaluate dentin bond strength, microTBS test was performed at a crosshead speed of 1 mm/min. For ultrastructural evaluation of the adhesive interfaces, SEM was used to examine the interfaces of the bonded specimens after acid-base challenge. The microTBS of NT was not determined, while that of 10-3 was significantly higher than that of PA (p < 0.05). With PA and 10-3, the hybrid layer was clearly observed, but no so for the acid-base resistant zone. Wall lesion was found in NT only. In conclusion, hybridization is vital to improving microTBS to dentin and enhancing resistance at the adhesive interface against acid-base challenge. PMID:19496398

Takagaki, Tomohiro; Nikaido, Toru; Tsuchiya, Satoko; Ikeda, Masaomi; Foxton, Richard M; Tagami, Junji

2009-03-01

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

Design and characterization of an efficient CYP105A1-based whole-cell biocatalyst for the conversion of resin acid diterpenoids in permeabilized Escherichia coli.  

PubMed

Cytochrome P450 enzymes exhibit a tremendous potential for biotechnological applications due to their ability to introduce oxygen into non-activated carbon atoms. Their catalytic diversity is complemented by a broad substrate range covering many natural compounds. Especially the functionalization of terpenoids by P450s becomes increasingly interesting due to the diverse biological effects of these compounds. The bacterial CYP105A1 from Streptomyces griseolus was recently identified to carry out a one-step hydroxylation of several abietane-type resin acids. In this work, a whole-cell system for CYP105A1 with its heterologous electron transfer proteins Arh1 and Etp1(fd) from Schizosaccharomyces pombe was designed in Escherichia coli JM109 cells. Additionally, an enzyme-coupled cofactor regeneration system was integrated by co-expression of alcohol dehydrogenase from Lactobacillus brevis. In order to overcome mass transfer limitations of substrate into the cell, different agents were tested towards their permeabilizing activity on the E. coli membrane. The peptide antibiotic polymyxin B proved to be the most effective permeabilizer. After optimising the expression and conversion conditions, the cells were able to completely convert 200 ?M of abietic acid into 15-hydroxyabietic acid within 2 h, exhibiting an initial conversion rate of 125 ?M/h. These results demonstrate the high potential of this whole-cell system for the synthesis of functionalized resin acid diterpenoids. PMID:23793341

Janocha, Simon; Bernhardt, Rita

2013-09-01

98

FB-Line resin testing final report  

SciTech Connect

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form, and the Dowex 50W resins have characteristic water retention capacities. These tests conclude that the ion exchange resins in use in FB-Line meet the approved safety document criteria for cross-linking, ionic form, and resin type.

Bannochie, C.J.

1992-01-23

99

Adsorption of humic acid by bi-functional resin JN-10 and the effect of alkali-earth metal ions on the adsorption.  

PubMed

This study investigated the adsorption of humic acid (HA) by bi-functional resin JN-10, which removed the HA more effectively than the commercial resins D-301, D-201, XAD-7, and globe active carbon F-400. The difference between the FT-IR spectroscopy and (13)C NMR analysis of JN-10 before and after it adsorbing the HA revealed that both hydrophobic interaction and electric attraction were the adsorption force for the HA. The related thermodynamic parameters exhibited that the adsorption of the HA by JN-10 was an endothermic process. The occurring of adsorption was due to the increase of entropy, and the electric attraction was also a main adsorption force. In order to investigate the influence of the molecule weight (MW) of the HA on its removal by JN-10, the HA with the MWs ranging from 2000 to 100,000 Da was divided into six fractions by ultra-filtration. The HA with a medium MW (6000-10,000 Da) was preferentially removed by JN-10 due to the synergistic effect of hydrophilicity, molecular size, and aromaticity of the HA. The adsorption capacity of JN-10 for the HA increased in the presence of low concentration of alkali-earth metal ions Ca(2+) and Mg(2+), which neutralized the negative charges of the HA, but it decreased as the concentration of these ions increased because the hydrates formed by the alkali-earth metal ions occupied the adsorption sites of the resin. PMID:20074851

Wang, Jinnan; Zhou, Yang; Li, Aimin; Xu, Li

2010-04-15

100

Synthesis and application of a new chelating resin functionalized with 2,3-dihydroxy benzoic acid for Fe(III) determination in water samples by flame atomic absorption spectrometry  

Microsoft Academic Search

To obtain a selective chelating resin for separation and preconcentration of Fe(III) ions in various water samples, amberlite XAD-4 was functionalized with 2,3-dihydroxy benzoic acid by coupling it through an –NN– spacer. The resulting resin, characterized by thermogravimetric analysis and infrared (IR) spectroscopy, was packed in a minicolumn to be used as a sorbent. It was shown that Fe3+ ions

Mohammad Saeid Hosseini; Haidar Raissi; Sara Madarshahian

2006-01-01

101

Distribution coefficients of 52 elements on a strongly basic anion-exchange resin in aqueous solutions of orthophosphoric acid  

Microsoft Academic Search

BS>Preliminary results of the systematic determination of the ; distribution coefficients of 52 elements on Dowex 1-X8 resin in HâPOâ ; solutions at concentrations from 0.1 to 14 M at room temperature are reported. ; Adsorbabilities of elements show marked differences even for elements in the same ; group of the Periodic Table. With few exceptions the distribution coefficients ;

H. Polkowska-Motrenko; R. Dybczynski

1974-01-01

102

Ion-exclusion chromatographic separations of C1-C6 aliphatic carboxylic acids on a sulfonated styrene-divinylbenzene co-polymer resin column with 5-methylhexanoic acid as eluent.  

PubMed

The application of C7 aliphatic carboxylic acids (heptanoic, 2-methylhexanoic, 5-methylhexanoic and 2,2-dimethyl-n-valeric acids) as eluents in ion-exclusion chromatography with conductimetric detection for C1-C6 aliphatic carboxylic acids (formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, isocaproic and caproic acids) was carried out using a highly sulfonated styrene-divinylbenzene co-polymer resin (TSKgel SCX) in the H+ form as a stationary phase. When using 0.05 mM sulfuric acid at pH 4.0 as the eluent, peak shapes of hydrophobic carboxylic acids (isovaleric, valeric, isocaproic and caproic acids) were tailed strongly. In contrast, when using 1 mM these C7 carboxylic acids at pH ca. 4 as the eluents, although system peaks (vacant peaks) corresponding to these C7 carboxylic acids appeared, peak shapes of these hydrophobic acids were improved drastically. Excellent simultaneous separation and relatively high sensitive conductimetric detection for these C1-C6 aliphatic carboxylic acids were achieved in 25 min on the TSKgel SCX column (150 x 6 mm I.D.) using 1 mM 5-methylhexanoic acid at pH 4.0 as the eluent. PMID:12830882

Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi

2003-05-16

103

Evolution of Diterpene Metabolism: Sitka Spruce CYP720B4 Catalyzes Multiple Oxidations in Resin Acid Biosynthesis of Conifer Defense against Insects1[C][W][OA  

PubMed Central

Diterpene resin acids (DRAs) are specialized (secondary) metabolites of the oleoresin defense of conifers produced by diterpene synthases and cytochrome P450s of the CYP720B family. The evolution of DRA metabolism shares common origins with the biosynthesis of ent-kaurenoic acid, which is highly conserved in general (primary) metabolism of gibberellin biosynthesis. Transcriptome mining in species of spruce (Picea) and pine (Pinus) revealed CYP720Bs of four distinct clades. We cloned a comprehensive set of 12 different Sitka spruce (Picea sitchensis) CYP720Bs as full-length cDNAs. Spatial expression profiles, methyl jasmonate induction, and transcript enrichment in terpenoid-producing resin ducts suggested a role of CYP720B4 in DRA biosynthesis. CYP720B4 was characterized as a multisubstrate, multifunctional enzyme by the formation of oxygenated diterpenoids in metabolically engineered yeast, yeast in vivo transformation of diterpene substrates, in vitro assays with CYP720B4 protein produced in Escherichia coli, and alteration of DRA profiles in RNA interference-suppressed spruce seedlings. CYP720B4 was active with 24 different diterpenoid substrates, catalyzing consecutive C-18 oxidations in the biosynthesis of an array of diterpene alcohols, aldehydes, and acids. CYP720B4 was most active in the formation of dehydroabietic acid, a compound associated with insect resistance of Sitka spruce. We identified patterns of convergent evolution of CYP720B4 in DRA metabolism and ent-kaurene oxidase CYP701 in gibberellin metabolism and revealed differences in the evolution of specialized and general diterpene metabolism in a gymnosperm. The genomic and functional characterization of the gymnosperm CYP720B family highlights that the evolution of specialized metabolism involves substantial diversification relative to conserved, general metabolism. PMID:21994349

Hamberger, Bjorn; Ohnishi, Toshiyuki; Hamberger, Britta; Seguin, Armand; Bohlmann, Jorg

2011-01-01

104

Evaluation of ultrafiltration membranes in the purification of guayule resin  

E-print Network

. Extensive research on the utilization of guayule resin is being conducted (5) resulting in a need to fractionate certain constituents of the resin to suit specific purposes. Research on the composition of the resin is still going on and about, 44 wtFs of...' the resin remains uncharacterized. The characterized portion consists of glycolipids, phosphatidic acids, flavonoids (6), flavonoid glyco- sides, solubilized lignins and polyacetylenes (7). Analyses have also indicated tliat the resin composition changes...

Jeyaseelan, Ranjit S.

2012-06-07

105

Time- and concentration-dependent metabolic and genomic responses to exposure to resin acids in brown trout (Salmo trutta m. lacustris).  

PubMed

The presence of metabolically conjugated resin acids (RAs) in the bile is considered to be a sensitive indicator for exposure of fish to pulp and paper industry effluents; however, to our knowledge, no comprehensive kinetic study of this response has been made. Juvenile brown trout (Salmo trutta m. lacustris) were exposed to a waterborne mixture of seven RAs (wood rosin) in time (0.1-192.0 h; average concentration, 8 microg/L) and dose (average concentrations, 0, 0.6, 4, 14, and 78 microg/L; 10 d) series, and total RAs were analyzed in bile. In time-dependent exposure, total RAs in bile increased up to 24 h. In concentration-dependent exposure, RAs increased along with the concentration of RAs in water, revealing a high-capacity biotransformation and elimination system in trout liver. In concentration-dependent exposures, the effects on the hepatic transcriptome was studied using a high-density cDNA microarray, and dose-dependent changes were found in a large number of genes. Resin acids interfered with iron metabolism, as evidenced by the decrease in transcripts for iron transporters and heme-containing proteins. Expression of genes encoding for enzymes degrading reactive oxygen species also decreased. Coordinated down-regulation of the protein biosynthesis machinery could result from inhibition of the energy metabolism. A number of changes in gene expression indicated recovery and remodeling of hepatic tissues. We conclude that analysis of total RAs in the bile provides a sensitive and quantitative tool for assessing the exposure of fish to waterborne RAs, whereas multiple gene expression analyses are able to elucidate simultaneous cellular functions for use as potential biomarkers of RAs. PMID:17702544

Meriläinen, Päivi S; Krasnov, Aleksei; Oikari, Aimo

2007-09-01

106

Acylated glycosides of hydroxy fatty acid methyl esters generated from the crude resin glycoside (pharbitin) of seeds of Pharbitis nil by treatment with indium(III) chloride in methanol.  

PubMed

Treatment of the crude ether-insoluble resin glycoside (convolvulin) from seeds of Pharbitis nil (Pharbitis Semen), called pharbitin, with indium(III) chloride in methanol provided seven oligoglycosides of hydroxy fatty acid methyl esters partially acylated by 2-methyl-3-hydroxybutyric (nilic) and 2S-methylbutyric acids. Their structures were elucidated on the basis of NMR and MS data and chemical conversions. PMID:20939542

Ono, Masateru; Takigawa, Ayako; Mineno, Tomoko; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ikeda, Tsuyoshi; Fukuda-Teramachi, Emiko; Noda, Naoki; Miyahara, Kazumoto

2010-11-29

107

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

Microsoft Academic Search

Indian frankincense is a gum resin from Boswellia serrata of Burseraceae used in Ayurveda and Western medicine for the antinflammatory effects of boswellic acids, particularly 3-O-acetyl-11-keto-?-boswellic acid (AKBA). We evaluated in vitro cytotoxicities of B. serrata extract and AKBA on differentiated and undifferentiated keratinocytes (HaCaT and NCTC 2544), and foetal dermal fibroblasts (HFFF2), using neutral red uptake (NRU), MTT, and

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

2008-01-01

108

FB-Line resin testing final report  

Microsoft Academic Search

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer`s specified ionic type and form,

Bannochie

1992-01-01

109

FB-Line resin testing final report  

Microsoft Academic Search

The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form,

Bannochie

1992-01-01

110

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

PubMed

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

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

2014-08-01

111

Distributed Drug Discovery, Part 2: Global Rehearsal of Alkylating Agents for the Synthesis of Resin-Bound Unnatural Amino Acids and Virtual D3 Catalog Construction  

PubMed Central

Distributed Drug Discovery (D3) proposes solving large drug discovery problems by breaking them into smaller units for processing at multiple sites. A key component of the synthetic and computational stages of D3 is the global rehearsal of prospective reagents and their subsequent use in the creation of virtual catalogs of molecules accessible by simple, inexpensive combinatorial chemistry. The first section of this article documents the feasibility of the synthetic component of Distributed Drug Discovery. Twenty-four alkylating agents were rehearsed in the United States, Poland, Russia, and Spain, for their utility in the synthesis of resin-bound unnatural amino acids 1, key intermediates in many combinatorial chemistry procedures. This global reagent rehearsal, coupled to virtual library generation, increases the likelihood that any member of that virtual library can be made. It facilitates the realistic integration of worldwide virtual D3 catalog computational analysis with synthesis. The second part of this article describes the creation of the first virtual D3 catalog. It reports the enumeration of 24?416 acylated unnatural amino acids 5, assembled from lists of either rehearsed or well-precedented alkylating and acylating reagents, and describes how the resulting catalog can be freely accessed, searched, and downloaded by the scientific community. PMID:19105725

2008-01-01

112

40 CFR 414.40 - Applicability; description of the thermoplastic resins subcategory.  

Code of Federal Regulations, 2010 CFR

...Nitrate *Ethylene-Methacrylic Acid Copolymers *Ethylene-Vinyl Acetate Copolymers *Fatty Acid Resins *Fluorocarbon Polymers...Alpha)Olefins Polyacrylic Acid *Polyamides *Polyarylamides... *Polybutenes Polybutenyl Succinic Anhydride...

2010-07-01

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

Gold recovery with ion exchange used resins  

Microsoft Academic Search

In this paper one strong acidic, one strong basic and one weak basic ion-exchange resins, considered as exhausted in an industrial demineralizing plant, are screened for gold recovery from cyanide solutions. Based on the observed ability for the recovery and on the ease of regeneration, the weak base anion exchanger Purolite A-100 is selected. This spent resin is stable until

Carmen P. Gomes; Manuel F. Almeida; José M. Loureiro

2001-01-01

115

Novolak resin analogs for resist applications  

NASA Astrophysics Data System (ADS)

Novolak resins, used to make typical g or i-line resists, are commonly made by condensing phenolic monomers with aldehydes. In the strictest definition of novolaks the aldehyde of choice is always formaldehyde. Under the acid catalyzed conditions generally used to make novolak the resins the carbocations formed by the protonation of the aldehydic carbonyl react with the phenolic reactant(s) to form the resins with elimination of water. Other aldehydes or low molecular weight ketones have been used on occasion to make useful analog for resist applications. Competing aldol condensations may interfere with isolation of pure polymeric resins especially in the case of ketones. Unique novolak resin analogs have been made by condensing `masked' bifunctional electrophiles with phenolic reactants under acidic conditions similar to standard novolak resin techniques. These resins were used as replacements for novolak resins and showed increased image contrast and thermal resistance. They were also used as photoactive compound backbones. Low molecular weight resins made with polyhydroxy aromatic phenolic monomers were especially useful as speed enhancing additives in thick film applications.

Wanat, Stan F.; Jensen, Kathryn H.; Lu, Ping-Hung; McKenzie, Douglas S.

1998-06-01

116

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

117

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

118

SPECTROSCOPIC STUDIES OF PETROLEUM RESINS  

Microsoft Academic Search

Resin fractions containing heteroatoms obtained from deasphaltened oils of petroleum residues (500C+) of Bombay High 7lpar;BH) and Gujrat Crude Mix (GCM) have been separated into acidic, basic and neutral Lewis base (NLB) types employing chromatographic methods. Ultimate compositions of these fractions have been determined for deducing the average molecular formulae. Infrared spectroscopy has been employed for assigning various heteroatomic functional

S. L. S. Sarowha; I. D. Singh

1988-01-01

119

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2010 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2010-04-01

120

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2012 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2012-04-01

121

21 CFR 177.1556 - Polyaryletherketone resins.  

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2014-04-01

122

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2013 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2013-04-01

123

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2011 CFR

...that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature. (b) Optional adjuvant substances. The basic...

2011-04-01

124

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

125

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

126

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

127

Magnetic ion-exchange resin treatment: impact of water type and resin use.  

PubMed

Three raw waters of fundamentally different natural organic matter (NOM) character were treated by magnetic resin using a bench-scale method designed to mimic how the resin is used in continuous operation. Increasing water hydrophobicity resulted in reduced dissolved organic carbon (DOC) removal with removal of 56%, 33% and 25% for waters containing 21%, 50% and 75% hydrophobic NOM, respectively. Study of consecutive resin uses showed that the NOM in the hydrophobic water had high affinity for the resin shown by DOC removal of 65% after the first use of the resin. This dropped to 25% DOC removal after 15 consecutive resin uses. For the more hydrophilic waters, NOM removal remained consistent after each resin use. The hydrophobic sample contained higher MW NOM that was capable of blocking resin sites that prevented continual adsorption of organics on to the resin. The hydrophilic NOM containing a large proportion of hydrophilic acids was consistently removed to around 60%. The water containing algogenic-derived NOM was poorly removed by magnetic resin. Subsequent coagulation showed higher removal with increasing hydrophobicity. PMID:18155745

Mergen, Max R D; Jefferson, Bruce; Parsons, Simon A; Jarvis, Peter

2008-04-01

128

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

129

Morphology of resin-dentin interfaces after Er,Cr:YSGG laser and acid etching preparation and application of different bonding systems.  

PubMed

The goal of this study was to show the modifications in the ultrastructure of the dentin surface morphology following different surface treatments. The stability of the adhesive compound with dentin after laser preparation compared with conventional preparation using different bonding agents was evaluated. An Er,Cr:YSGG laser and 36% phosphoric acid in combination with various bonding systems were used. A total of 100 caries-free human third molars were used in this study. Immediately after surgical removal teeth were cut using a band saw and 1-mm thick dentin slices were created starting at a distance of 4 mm from the cusp plane to ensure complete removal of the enamel. The discs were polished with silicon carbide paper into rectangular shapes to a size of 6 × 4 mm (±0,2 mm).The discs as well as the remaining teeth stumps were stored in 0.9% NaCl at room temperature. The specimens were divided into three main groups (group I laser group, group II etch group, group III laser and etch group) and each group was subdivided into three subgroups which were allocated to the different bonding systems (subgroup A Excite, subgroup B Scotchbond, subgroup C Syntac). Each disc and the corresponding tooth stump were treated in the same way. After preparation the bonding composite material was applied according to the manufacturers' guidelines in a hollow tube of 2 mm diameter to the disc as well as to the corresponding tooth stump. Shear bond strength testing and environmental scanning electron microscopy were used to assess the morphology and stability of the resin-dentin interface. The self-etching bonding system showed the highest and the most constant shear values in all three main groups, thus enabling etching with phosphoric acid after laser preparation to be avoided. Thus we conclude that laser preparation creates a surface texture that allows prediction of the quality of the restoration without the risk of negative influences during the following treatment steps. This can easily and repeatedly be achieved. PMID:21948398

Beer, Franziska; Buchmair, Alfred; Körpert, Wolfram; Marvastian, Leila; Wernisch, Johann; Moritz, Andreas

2012-07-01

130

DIPHONIX-CS : A NOVEL COMBINED CESIUM AND STRONTIUM SELECTIVE ION EXCHANGE RESIN  

Microsoft Academic Search

The recently developed Diphonix® resin contains the geminally substituted diphosphonic acid ligand chemically bonded to a styrene-divinylbenzene copolymer. The resin exhibits an extraordinarily strong affinity for actinides, especially in the terra- and hexavalent oxidation states. Therefore the resin has potential for application in TRU removal from nuclear wastes. The Diphonix-CS resin is a Diphonix-type resin that contains also phenolic groups

R. Chiarizia; E. P. Horwitz; R. A. Beauvais; S. D. Alexandratos

1998-01-01

131

Resin processing system  

SciTech Connect

This patent describes a resin processing system for use in chemical decontamination of nuclear reactor primary systems. It comprises a fresh resin supply tank; a batching tank; a fresh resin pump connected to the fresh resin supply tank and the batching tank; a plurality of demineralizers wherein process fluids are demineralized; a resin feed pump connected to the batching tank capable of transporting fresh resin from the batching tank; a movable connection means connecting the resin feed pump to one of the plurality of demineralizers; a sluice water supply tank; a sluice water pump connected to the sluice water supply tank and the plurality of demineralizers; a spent resin storage tank connected to each of the plurality of demineralizers; a recycle pump connected to an outlet of the spent resin storage tank and having a pump outlet connected to the sluice water supply tank; and a screen at the outlet of the spent resin storage tank to retain spent resin within the spent resin storage tank while allowing sluice water to be recycled.

Corpora, G.J.; Schlonski, J.S.; Miller, P.E.; Bauer, F.I.

1992-08-18

132

A mechanism for enhancing ionic accessibility into selective ion exchange resins  

SciTech Connect

A bifunctional monophosphonic/sulfonic acid ion exchange resin with high capacity has been synthesized. Metal ion studies have been carried out with europium, americium, and ferric nitrate in solutions of varying acidity, with and without sodium nitrate added. The bifunctional resin complexes far higher levels of Eu(III) from 0.5 and 1 N nitric acid than the monofunctional phosphonic acid resin. It is postulated that the sulfonic acid ligand provides an access mechanism for the metal ions into the polymer matrix by hydrating the matrix and preventing its collapse in high ionic strength solutions thus allowing for rapid ionic complexation by the selective phosphonic acid ligands. The bifunctional monophosphonic/sulfonic acid resin has both ligands bound to a polystyrene support. It complexes higher levels of metal ions than a comparable resin differing only by having the monophosphonic acid ligand directly bound to the C-C backbone. Results are compared to a diphosphonic/sulfonic acid resin.

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

1998-07-01

133

Effect of Resins and DBSA on Asphaltene Precipitation from Petroleum Fluids  

E-print Network

of various resins and dodecyl benzene sulfonic acid (DBSA) amphiphile on asphaltene precipitation from that of resins. When the DBSA amphiphile is mixed with the petroleum fluid at different concentrations, we

Firoozabadi, Abbas

134

Resin glycosides. XV. Simonins I-V, ether-soluble resin glycosides (jalapins) from the roots of Ipomoea batatas (cv. Simon).  

PubMed

Five new ether-soluble resin glycosides (jalapins), simonins I-V, have been isolated from the roots of Ipomoea batatas and characterized on the bases of chemical and spectral data. Simonin I is the first example of resin glycoside with aromatic acid (trans-cinnamic acid) as a component organic acid. PMID:1294318

Noda, N; Yoda, S; Kawasaki, T; Miyahara, K

1992-12-01

135

Polyester Resin Hazards  

PubMed Central

Polyester resins are being increasingly used in industry. These resins require the addition of catalysts and accelerators. The handling of polyester resin system materials may give rise to skin irritations, allergic reactions, and burns. The burns are probably due to styrene and organic peroxides. Atmospheric pollution from styrene and explosion and fire risks from organic peroxides must be prevented. Where dimethylaniline is used scrupulous cleanliness and no-touch technique must be enforced. Handling precautions are suggested. Images PMID:14014495

Bourne, L. B.; Milner, F. J. M.

1963-01-01

136

Preparation of site-selective ion-exchange resins  

SciTech Connect

Ion-exchange resins were prepared by copolymerization of styrenic monomers with metal ion complex compounds bearing polymerizable ligands. Removal of the metal ions by acid washing produced sites in the resins which contained ligands configured to match the bonding characteristics of the ions used in their construction. This template procedure was performed with Ni{sup 2+} and Cu{sup 2+} ions, and comparisons were made of exchange capacities and equilibrium constants for templated and untemplated resins. Templated resins showed order of magnitude capacity preferences for the ion used in their preparation. Equilibrium constants were found to be inversely related to capacities.

Harkins, D.A.; Schweitzer, G.K. (Univ. of Tennessee, Knoxville (USA))

1991-01-01

137

Improved well stimulation with resin-coated proppants  

SciTech Connect

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

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

1983-02-01

138

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

139

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

140

IRRADIATED PETROLEUM RESINS  

Microsoft Academic Search

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

J. E. Shewmaker; J. F. Nelson

1963-01-01

141

Resin catalysts and method of preparation  

DOEpatents

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

Smith, L.A. Jr.

1986-12-16

142

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

143

Maleimide Functionalized Siloxane Resins  

SciTech Connect

Polyorganosiloxanes are a commercially important class of compounds. They exhibit many important properties, including very low glass transition temperatures, making them useful over a wide temperature range. In practice, the polysiloxane polymer is often mixed with a filler material to help improve its mechanical properties. An alternative method for increasing polymer mechanical strength is through the incorporation of certain substituents on the polymer backbone. Hard substituents such as carbonates and imides generally result in improved mechanical properties of polysiloxanes. In this paper, we present the preparation of novel polysiloxane resins modified with hard maleimide substituents. Protected ethoxysilyl-substituted propyl-maleimides were prepared. The maleimide substituent was protected with a furanyl group and the monomer polymerized under aqueous acidic conditions. At elevated temperatures (>120 C), the polymer undergoes retro Diels-Alder reaction with release of foran (Equation 1). The deprotected polymer can then be selectively crosslinked by a forward Diels-Alder reaction (in the presence of a co-reactant having two or more dime functionalities).

Loy, D.A.; Shaltout, R.M.

1999-04-01

144

Reillex/trademark/ HPQ: A new, macroporous polyvinylpyridine resin for separating plutonium using nitrate anion exchange  

SciTech Connect

Anion exchange in nitric acid is the major aqueous process used to recover and purify plutonium from impure scrap materials. Most strong-base anion exchange resins incorporate a styrene-divinylbenzene copolymer. A newly available, macroporous anion exchange resin based on a copolymer of 1-methyl-4-vinylpyridine and divinylbenzene has been evaluated. Comparative data for Pu(IV) sorption kinetics and capacity are presented for this new resin and two other commonly used anion exchange resins. The new resin offers high capacity and rapid sorption kinetics for Pu(IV) from nitric acid, as well as greater stability to chemical and radiolytic degradation. 8 refs., 12 figs.

Marsh, S.F.

1989-01-01

145

Radiation testing of organic ion exchange resins  

SciTech Connect

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

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

1995-09-01

146

Adsorption and removal of oxo-anions of arsenic and selenium on the zirconium(IV) loaded polymer resin functionalized with diethylenetriamine-N,N,N',N'-polyacetic acid.  

PubMed

A polymer adsorbent in which a Zr(IV)-edta complex analogue is immobilized has been prepared and applied to the removal of oxo-anions of As(III), As(V) and Se(IV). Effective retention of these anions has been demonstrated with the proposed polymer complex system. The adsorption mechanism of oxo-anions onto the Zr(IV)-chelated polymer complex has been investigated using Zr(IV)-edta as the model compound. The formation of mixed complexes with oxo-anions has been exemplified by the isolation of the carbonato complex K2[Zr(CO3)edta].3H2O, the structure of which has been confirmed by X-ray crystallography. NMR study suggests that oxo-anions that form weak or moderate conjugate acids, including those of As(III), As(V) and Se(IV), can form mixed complexes with Zr(IV)-edta using the unsaturated coordination site. However, oxo-anions of strong conjugate acids did not show any appreciable interaction with this complex. According to these observations, retention of oxo-anions on the Zr(IV)-chelated polymer complex has been interpreted by a ligand substitution reaction. The adsorption characteristics of As(III), As(V) and Se(IV) on the Zr(IV)-loaded resin have been examined with respect to the equilibrium adsorption, percentage extraction and the effect of co-existing ions. The adsorption and desorption cycles of the oxo-anions have been demonstrated using a column packed with the proposed resin without any loss of column performance, which indicates the possibility for repeated use. PMID:11296739

Suzuki, T M; Tanaka, D A; Tanco, M A; Kanesato, M; Yokoyama, T

2000-12-01

147

Benzonorbornadiene end caps for PMR resins  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

148

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

149

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

150

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

151

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

152

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

NASA Astrophysics Data System (ADS)

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

Nakayama, Morio

153

Guayule resin separation and purification  

E-print Network

to investigate economic viability. The composition of the resin is only partially known. A substantial portion, about 44%, of the resin remains uncharacterized. This uncharacterized portion is of low volatility (5). The characterized portion consists... resin chromatography most of the mass elutes in the 2nd fraction. This is possibly so because of the difference in composition of the two resins. 30 Table 2. Column chromatography of xylene resins over basic alumina Fraction Eluting solvent hexane...

Bajwa, Mohinder P.S.

2012-06-07

154

Applications of fossil resin studies to an understanding of depositional and paleoenvironments  

SciTech Connect

Fossil resins are polymerized terpene (isoprenoid) acids. Because of their complexity and resulting variability, isoprenoids have been useful for their information content and geochemical signatures. Fossil resin occurs throughout a 304-ft continuous core and correlated outcrops from the Late Cretaceous Fruitland Formation in the Fossil Forest study area, San Juan basin, New Mexico, in associated with coal, sandstone, shale, and petrified wood. Fourier transformation infrared (FTIR) spectra of resin from throughout the sequence reveal oxidative and chemical variation. FTIR spectra of resin incorporated in petrified wood differ from those of resin exposed to the paleoatmosphere in the same individual tree. This study was initiated to complement previous studies related to analyses of fluid inclusions in fossil resin and to elucidate reactions between the resin matrix and possible atmospheric inclusions. It was done in conjunction with extensive trace-element, palynological, and mineralogical analyses. Understanding the biogeochemistry of fossil resin may elucidate the origin, diagenesis, and depositional environment of smaller concentrations of isoprenoids.

Bellis, D.; Wolberg, D.L. (New Mexico Bureau of Mines and Mineral Resources, Socorro (USA))

1989-09-01

155

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

156

Synthesis and Characterization of Linear and Branched Polylactic Acid for Use in Food Packaging Applications.  

E-print Network

?? Polylactic acid (PLA) resins of various molecular weights and molecular weight distributions were synthesized. Linear, narrow molecular weight distribution (MWD) PLA resins were synthesized,… (more)

Bentz, Kyle C

2011-01-01

157

Color test for selective detection of secondary amines on resin and in solution.  

PubMed

Resins for solid-phase synthesis give orange to red-brown resin beads selectively when secondary amines are present on the resin when treated with a solution of acetaldehyde and an Fmoc-amino acid in NMP. The method shows good specificity and gives colorless beads when exposed to a variety of other functional groups. Furthermore, the acetaldehyde/Fmoc amino acid method can be used as a selective colorimetric test for secondary amines in solution. PMID:25360626

Boas, Ulrik; Mirsharghi, Sahar

2014-11-21

158

Determination of isotopic composition of dissolved copper in seawater by multi-collector inductively coupled plasma mass spectrometry after pre-concentration using an ethylenediaminetriacetic acid chelating resin.  

PubMed

Copper is an essential trace metal that shows a vertical recycled-scavenged profile in the ocean. To help elucidate the biogeochemical cycling of Cu in the present and past oceans, it is important to determine the distribution of Cu isotopes in seawater. However, precise isotopic analysis of Cu has been impaired by the low concentrations of Cu as well as co-existing elements that interfere with measurements by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The objective of this study is to develop a simple Cu pre-concentration method using Nobias-chelate PA1 resin (Hitachi High Technologies). This extraction followed by anion exchange, allows precise analysis of the Cu isotopic composition in seawater. Using this method, Cu was quantitatively concentrated from seawater and >99.9999% of the alkali and alkaline earth metals were removed. The technique has a low procedural blank of 0.70 ng for Cu for a 2L sample and the precision of the Cu isotopic analysis was ±0.07‰ (±2SD, n=6). We applied this method to seawater reference materials (i.e., CASS-5 and NASS-6) and seawater samples obtained from the northwestern Pacific Ocean. The range of dissolved ?(65)Cu was 0.40-0.68‰. PMID:23746405

Takano, Shotaro; Tanimizu, Masaharu; Hirata, Takafumi; Sohrin, Yoshiki

2013-06-19

159

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

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

2014-07-01

160

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

161

Antioxidant activity of natural resins and bioactive triterpenes in oil substrates  

Microsoft Academic Search

Natural resins that possess biological properties (Pistacia lentiscus var. Chia, Commiphora myrrh, Boswellia serrata and Gum storax) and the bioactive triterpenes (oleanolic acid and ursolic acid) were studied for their antioxidant activities. Lard, corn oil, olive oil and sunflower oil were used as oil substrates for the antioxidant assay.Pistacia lentiscus resin showed significant antioxidant activity in each of the oil

A. N. Assimopoulou; S. N. Zlatanos; V. P. Papageorgiou

2005-01-01

162

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

163

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

164

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

165

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

166

Selective synthesis of perfumery grade cyclohexyl esters from cyclohexene and carboxylic acids over ion exchange resins: an example of 100% atom economy  

Microsoft Academic Search

Summary Esterification is important in the perfumery and flavour chemical industry, wherein, both homogeneous and heterogeneous cata- lysts have been widely used. The use of solid acid catalysts can be effective from the view of activity, selectivity, reusability and economy in the manufacture of perfumery esters. This paper delineates a 100% atom economical process for the preparation of cyclohexyl esters

G. D. Yadav; P. K. Goel

2000-01-01

167

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... 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 to be dried to specified levels...

Joseph, B.; Thuro, G.

168

Production of petroleum polymer resins  

Microsoft Academic Search

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

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

1988-01-01

169

Powdered resin for condensate polishing  

Microsoft Academic Search

Powdered resin systems have a lot to offer in the deionization of low TDS waters, as can be seen in the wide use of this process for the treatment of condensate in the electric power industry. I believe that as new ion-exchange resins are developed, we will see the powdered ion-exchange resin process adopted in other industries. At this time,

Richard Hetherington

1997-01-01

170

Sulfo cation-exchange resins as heterogeneous catalysts for the reaction of styrene with formaldehyde  

SciTech Connect

Macroporous and gel sulfo cation-exchange resins are active catalysts for the condensation of styrene with formaldehyde. The product, 4-phenyl-1,3-dioxane was obtained in up to 97% yield. The activity of macroporous sulfo cation-exchange resins increases with decreasing particle diameter but in the case of the gel samples, granule size has only a slight effect on the reaction rate. The enhanced activity of sulfo cation-exchange resins is presumably a result of the high value of the acidity function H/sub 0/ of the sulfonic acid groups of the cation-exchange resin.

Kasymova, K.A.; Sharf, V.Z.; Litvin, E.F.; Grigor'eva, E.N.

1987-07-20

171

Glycidyl methacrylate based polymer resins with diethylene triamine tetra acetic acid functions for efficient removal of Ca(II) and Mg(II)  

Microsoft Academic Search

Crosslinked terpolymer beads prepared by suspension polymerization of glycidyl methacrylate (GMA) (0.4 mol), methyl methacrylate (MMA) (0.5 mol) and divinyl benzene (DVB) (0.1 mol) mixtures have been modified through epoxy functions in two steps: (i) by treating with excess of diethylene triamine (DETA); and (ii) by subsequent reaction with potassium chloroacetate. The resulting polymer possessing diethylene triamine tetra acetic acid

Bahire Filiz ?enkal; Niyazi Biçak

2001-01-01

172

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

173

Production of petroleum polymer resins  

SciTech Connect

A dark-colored styrene-indene resin and light-colored petroleum polymer resins of two types- SPP and Piroplast-2 are in commercial production in the Soviet Union. The raw material for the production of the dark-colored styrene-indene resin is heavy pyrolysis tar which is a residue from the distillation of liquid byproducts obtained in pyrolysis. The flow plans for the continuous production of SPP resin and Piroplast-2 are described. These resins are low cost materials as the original raw material is inexpensive and the production costs are low.

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

1988-09-01

174

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

175

Processing of continuous fiber composites using thermoplastic polyimide matrix resins  

SciTech Connect

Composites have been produced which contain a solvent resistant polyimide matrix with favorable physical properties. The polyimide matrix resin has been designated as P12. The prepegs used to produce the composite contain a low molecular weight resin which is the polyamic acid precursor to P12. Polymerization and imidization of the precursor resin occurs in-situ during processing. Similar commercial systems are often processed in an autoclave and pressure is used at high temperatures to obtain consolidation between prepreg laminates. Pressure is generally applied after polymerization and imidization are complete and at temperatures above the melting point of the polymer. In this research a significant decrease in composite void content was obtained by applying pressure earlier in the cure. Obtaining composites with low void content with these types of systems can be difficult. This is due in part to the generation of low molecular weight reaction by products, water and methanol. High void content results in a decrease in the physical properties of the composite structure. This is especially true for fracture properties. An empirical equation was used to describe the rate of resin removal from the composite to the bleeder cloth during processing. This equation is based on Springer-Loos resin flow model. The conditions in which this model does not apply were also determined. Determining resin removal rates is helpful in producing composites with consistent fiber/resin ratios. In addition, conditions which favor void growth can be prevented.

Kranjc, M.D.

1993-01-01

176

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

177

Studies on metal complexes of SMH resin  

Microsoft Academic Search

The nature of bonding in poly(styrene-co-maleic hydroxamic acid) resin complexes of Fe(III), Cu(II), Ni(II), and Co(II) was investigated using FT-i.r., electronic and EPR spectra. Ligand to metal bonding is through the hydroxamic acid-nitrogen. Fe(III), Co(II), and Ni(II) show octahedral geometry and Cu(II) shows a square planar geometry. Thermal decomposition studies by TG and DTA indicate catalysis of decomposition by the

Rita Mendez; K. Usha; K. K. Mohammed Yussuf; V. N. Sivasankara Pillai

1996-01-01

178

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

179

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

180

Morphological characterization of furfuraldehyde resins adsorbents  

SciTech Connect

Sugar cane is one of the most traditional plantation cultivated crops in large areas in Brazil. The State University of the North of Rio de Janeiro, UENF, is currently engaged in a program aimed to exploit the potentialities of sugar cane industry as a self sustained non-polluting enterprise. One of the projects being carried out at the UENF is the transformation of sugar cane bagasse in precursor materials for the industry of furan derivatives such as the furfuraldehyde resins obtained by acid catalysis. The possibility of employing acid catalyzed furfuraldehyde resins as selective adsorbents has arisen during a comprehensive study of physical-chemical adsorption properties of these materials. The morphology of these resins depend on the synthesis method. Scanning Electron Microscopic studies of these materials which were synthesized, in bulk (FH-M) and solution (FH-D), showed differences in surface density and particle size. Using mercury porosimeter techniques and BET adsorption methods, it was found different pore size distributions and a decrement in surface area when solvent was employed in the synthesis process. By thermogravimetric analysis it was found similar weight losses (6%) of water adsorption and a small differences in thermal stabilities.

Sanchez, R.; Monteiro, S.N. [State Univ. of the North of Rio de Janeiro (Brazil); D`Almeida, J.R. [Rio de Janeiro-Catholic Univ. (Brazil)

1996-12-31

181

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

182

Phenoxy resins containing pendent ethynyl groups and cured resins therefrom  

SciTech Connect

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

Hergenrother, P.M.

1984-05-01

183

Functional polycyclopentadiene resins via hydroboration process  

Microsoft Academic Search

This patent describes a process for preparing a functionalized petroleum resin. It comprises dissolving a petroleum resin in a solvent to form a solution, the resin being formed by polymerizing feeds containing cyclopentadiene, dicyclopentadiene and alkyl derivatives thereof, the resin having a norbornene moiety with a double bond; adding to the solution a borane, reacting the petroleum resin with the

T. C. Chung; E. Berluche; J. Bock; R. V. Kastrup

1992-01-01

184

Effect of resin sulfonation on the retention of polar organic compounds in solid-phase extraction  

Microsoft Academic Search

The hydrophobic nature of polymeric resins used in solid-phase extraction (SPE) often limits their efficiency by preventing intimate surface contact with aqueous samples. A polymeric resin modified by a series of chemical derivatizations with sulfuric acid was found to display excellent surface hydrophilicity and improved extraction efficiencies. The degree of sulfonation was found to play a vital role in determining

Philip J. Dumont; James S. Fritz

1995-01-01

185

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2012 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2012-04-01

186

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2013 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2013-04-01

187

21 CFR 178.3930 - Terpene resins.  

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2014-04-01

188

21 CFR 178.3930 - Terpene resins.  

Code of Federal Regulations, 2011 CFR

... Terpene resins. The terpene resins identified in paragraph (a) of this section may be safely used as components of polypropylene film intended for use in contact with food, and the terpene resins identified in paragraph (b) of this section may...

2011-04-01

189

Synthesis, characterization and some adsorption properties of TMMA chelating resin  

NASA Astrophysics Data System (ADS)

In order to separate U(VI) ions and lanthanide ions from acidic media, N, N, N', N'-tetramethylmalonamide, (TMMA), chelating resin was synthesized by chemically bonding the functional group to the main chain of chloromethylstyrene-divinylbenzene copolymer. Characterization of the resin in terms of IR, solid-NMR, porosity and elemental analysis suggested that TMMA was uniformly linked to the polymer particles following the expected synthetic scheme and that the introduction ratio was ca. 75%. The uptake behavior of Ce(III) ions and of U(VI) ions from different acidic media were investigated using the batch technique. The kinetic and equilibrium studies showed that the obtained resin is promising for the proposed separation.

Nogami, M.; Ismail, I. M.; Yamaguchi, M.; Suzuki, K.

2003-02-01

190

Uranium Removal from Contaminated Groundwater by Synthetic Resins  

SciTech Connect

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

Phillips, Debra H. [Queen's University, Belfast; Gu, Baohua [ORNL; Watson, David B [ORNL; Parmele, C. S. [Science Applications International Corporation (SAIC), Oak Ridge, TN

2008-01-01

191

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

SciTech Connect

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

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

1992-01-01

192

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

193

Processable High Temperature Laminating Resins.  

National Technical Information Service (NTIS)

P13N Polyimide Resin was modified to provide autoclave moldability for boron monofilament and graphite fiber prepregs and to improve the thermo-oxidative stability of composites. It was shown that a modified P13N resin provided autoclave molded boron and ...

R. W. Vaughan, R. J. Jones

1971-01-01

194

Platinum cluster catalysts supportedon porous chelate resin-metal complexes: Effect of resin porosity on catalytic activity  

SciTech Connect

Porous chelate resin-metal complexes were prepared from a commercial chelate resin having iminodiacetic acid moieties. This was accomplished by complexing with multivalent cations such as Al{sup 3+} and drying after washing with ethanol. The supported platinum cluster catalysts, formed by reducing the platinum ions on the porous chelate resin-metal complexes, had a mean diameter of 26 {Angstrom}, occupying pores approximately 40 {Angstrom} in diameter of the chelate resin-metal complexes. These systems were then used as catalysts during the hydrogenation of olefin or diene. The catalytic activity was found to depend on the type of metal ion used in the chelate resin-metal complexes, and it increased in the order of Na{sup +} < Mg{sup 2+} < Al{sup 3+}. The surface area of the chelate resin-metal complex, measured by a BET method, also increased in the same order, suggesting that the surface area is related to the catalytic activity. 23 refs., 6 figs., 3 tabs.

Toshima, Naoki; Teranishi, Toshiharu; Asanuma, Hiroyuki [Univ. of Tokoyo, Hongo, Bunkyo-ku (Japan)] [and others

1992-04-30

195

Diverse secondary interactions between ions exchanged into the resin phase and their analytical applications.  

PubMed

The research activities by the author's group to elucidate the chemical states of ions within the ion exchange resin phase are summarized. The resin with the higher exchange capacity has the smaller space available for ion exchange, and the higher cross linking degree interferes more with swelling of the resin. As a result, diverse secondary interactions between exchanged ions are observed on the resins of high exchange capacities and high cross linking degrees: the van der Waals contact results in incomplete exchange or enhanced dehydration of ions, hydrogen bond formation between acidic anions, and coadsorption of anions with metal ions. Contribution of the simple ion exchange mechanism to the reactions of iminodiactate-type chelating resins with metal ions in the acidic media is quantitatively discussed. The resulting complexes were successfully applied to preconcentration and separation of anions. PMID:24420244

Yuchi, Akio

2014-01-01

196

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

197

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

198

Resin reinforced expansion anchor system  

SciTech Connect

An expansion anchor assembly is described in combination with a dual compartment resin and cartridge inserted into a mine roof opening, the anchor assembly including: (a) an elongated bolt having a head at one end and threaded for a portion of its length at the other end; (b) an expansion member engaged with the threaded end of the bolt; (c) the expansion member including an expansion shell having a plurality of leaf segments; (d) a first means for engaging the expansion shell with the elongated bolt; (e) a wedge threaded on the elongated bolt for engagement with the expansion shell to urge the latter into gripping engagement with the mine roof; (f) a first resin passageway means on the outer surface of the wedge for permitting resin to gravitate therethrough; (g) the leaf segments of the expansion shell being separated to form a second resin passageway means aligned with the first resin passageway means, whereby resin may gravitate downwardly through substantially the entire length of the assembly, and (h) a second means within the first passageway and engageable with one of the leaf segments to prevent relative rotation of the wedge member with respect to the expansion shell; (i) the resin being mixed upon rotation of the bolt and expansion member and gravitating downwardly through the first and second passageway means into engagement with that portion of the mine roof defining the mine roof opening.

Clark, C.A.; Wright, R.L.

1988-08-16

199

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

200

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

SciTech Connect

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

Marsh, S.F.

1991-01-01

201

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

202

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

203

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

204

Pentasaccharide resin glycosides from Ipomoea cairica and their cytotoxic activities.  

PubMed

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

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

2013-11-01

205

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

206

Petroleum resins and their production  

Microsoft Academic Search

A process is described for the production of petroleum resins compatible with base polymers in hot melt formulations and having a softening point of from about 60°C. to about 120°C. and Gardner color of about 4 or less, comprising copolymerizing using a Friedel-Crafts catalyst. The mixture is substantially free form cyclopentadiene and dicyclopentadiene. This patent also describes a resin consisting

Luvinh

1989-01-01

207

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

208

Copper and boron fixation in wood by pyrolytic resins.  

PubMed

A phenol-formaldehyde (PF)-resin designed to penetrate wood and immobilize copper and boron in wood cells for protection against decay was investigated. The phenol portion of the PF-resin was partially substituted with pyrolysis oil derived from softwood bark. The objective was to reduce the environmental impact associated with the production of petroleum-borne phenol, as well as to improve the product economics. Leaching tests were conducted with three different formulas of resins containing 50%, 75% or 85% by weight of pyrolytic oil on a total phenol basis. The leachates were analyzed for the presence of copper by atomic absorption spectroscopy while inductively coupled plasma spectroscopy was used for boron detection. Copper leaching was reduced up to 18 times when comparing the treatments with and without the resin. Preservative leaching varied between wood species as well as between the resins containing different concentrations of pyrolytic oil. The organic leachates were measured using gas chromatography and mass spectroscopy. Trace amounts of organics, mostly acetic acid, were found in the leachates. PMID:18835155

Mourant, Daniel; Yang, Dian-Qing; Lu, Xiao; Riedl, Bernard; Roy, Christian

2009-02-01

209

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

SciTech Connect

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

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

1982-01-01

210

Alkyd-amino resins based on waste PET for coating applications  

SciTech Connect

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

Torlakoglu, A. [Department of Chemical Engineering, Faculty of Engineering, Istanbul University, 34320 Avcilar, Istanbul (Turkey); Gueclue, G. [Department of Chemical Engineering, Faculty of Engineering, Istanbul University, 34320 Avcilar, Istanbul (Turkey)], E-mail: gguclu@istanbul.edu.tr

2009-01-15

211

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

212

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

213

Phenolic cation exchange resin material for recovery of cesium and strontium  

SciTech Connect

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

1983-12-27

214

Demineralizer operation with morpholine and boric acid  

SciTech Connect

The effect on condensate and blowdown deep bed demineralizer performance of morpholine and boric acid are examined. The high concentration of morpholine required to reduce corrosion product transport exhausts demineralizer cation resin too fast to allow hydrogen cycle demineralizer operation. Extremely efficient resin separation and high crosslinked cation resins will be required to minimize sodium leakage during demineralizer morpholine cyde operation. Organic anions formed by morpholine decomposition tend to leak through demineralizers during amine cycle operation. Concentrations of these species vary markedly between plants. The anion resin selectivity coefficient for borate is low, and only a fraction of hydroxide form anion resin is converted to the borate form. Borate has little effect on condensate demineralizer sodium, chloride and sulfate leakage during hydrogen/borate cycle operation. However, sodium leakage increases during amine/borate cycle resin operation. In addition, silica is not effectively removed by anion resin in the presence of boric acid.

Siegwarth, D.P. (NWT Corp., San Jose, CA (United States))

1992-07-01

215

Functional polycyclopentadiene resins via hydroboration process  

SciTech Connect

This patent describes a process for preparing a functionalized petroleum resin. It comprises dissolving a petroleum resin in a solvent to form a solution, the resin being formed by polymerizing feeds containing cyclopentadiene, dicyclopentadiene and alkyl derivatives thereof, the resin having a norbornene moiety with a double bond; adding to the solution a borane, reacting the petroleum resin with the borane compound at about room temperature for a sufficient period of time to form a derivative of the petroleum resin containing a borane group; and reacting the derivative of the petroleum resin with a chemical agent capable of replacing the borane group of the petroleum resin derivative with a functional group, thereby converting the derivative into the functionalized petroleum resin.

Chung, T.C.; Berluche, E.; Bock, J.; Kastrup, R.V.

1992-03-03

216

Disposal of bead ion exchange resin wastes  

SciTech Connect

Bead ion exchange resin wastes are disposed of by a process which involves spray-drying a bead ion exchange resin waste in order to remove substantially all of the water present in such waste, including the water on the surface of the ion exchange resin beads and the water inside the ion exchange resin beads. The resulting dried ion exchange resin beads can then be solidified in a suitable solid matrix-forming material, such as a polymer, which solidifies to contain the dried ion exchange resin beads in a solid monolith suitable for disposal by burial or other conventional means.

Gay, R.L.; Granthan, L.F.

1985-12-17

217

Pilot scale comparison of enhanced coagulation with magnetic resin plus coagulation systems.  

PubMed

Previous work has shown that magnetic ion-exchange treatment before coagulation gives high natural organic matter (NOM) removal and reduced levels of disinfection byproduct when compared to conventional enhanced coagulation. The impact of the resin process on the downstream floc formation process after coagulation and the subsequent effect on clarification has not previously been shown. Water containing high concentrations of NOM were treated at pilot scale using (1) conventional enhanced coagulation and compared with (2) treatment using magnetic resin followed by coagulation at reduced doses of 50-70%. Bench scale testing was also carried out to determine floc properties for systems with and without resin pretreatment It was demonstrated that pretreatment using magnetic resin was able to significantly reduce the turbidity load onto filters as a result of the formation of a large and more robust floc. Resin pretreatment also improved NOM removal and reduced disinfection byproduct formation when compared with conventional coagulation. The turbidity load on to the filters following resin pretreatment was 1.5 +/- 0.7 NTU, whereas this value was 2.9 +/- 0.3 NTU for conventional coagulation. Flocs produced with resin pretreatment were larger than those produced by conventional coagulation, with a median floc size of 1000 microm compared to 600 microm. The improvement in floc properties following magnetic resin pretreatment was proposed to be due to the removal of NOM thatwas characteristic of carboxylic acids before the coagulation stage. PMID:18351105

Jarvis, Peter; Mergen, Max; Banks, Jenny; McIntosh, Brian; Parsons, Simon A; Jefferson, Bruce

2008-02-15

218

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

219

Sorption of SO/sub 2/ by stationary layers of granular ion-exchange resins from moist mixtures of gases  

SciTech Connect

The present investigation studied the process of freezing moist air from SO/sub 2/ in stationary layers of granular ion-exchange resins. Results indicated that the effective sorption of SO/sub 2/ by anion-exchange resins can take place from gas flows with moisture contents > 50 rel.%; for sorption on strongly acidic polymerization resins the favorable range of phi is 70-100%; polymerization anion-exchange resins are more effective in the purification of gases supersaturate with moisture. In the case of the continuous moistening of the layer of resin, the humidity of the gas of course had no significance, but the aerodynamic resistance of the layer of resin, amounting under the conditions shown in Table 1 to about 1000 N/m/sup 2/, rose approximately fivefold. The sorption capacity for SO/sub 2/ of the most effective anion-exchange resins under the conditions of the optimum humidity of the gases being purified at C/sub SO/sub 2// = 5 mg/liter (0.17 vol. %) and t = 20-25/sup 0/C amounted to 20-40 wt.% in relation to the dry resins and 10-15% in relation to the weight of the moist resins or 50-90 g/liter of moist resins.

Vulikh, A.I.; Zagorskaya, M.K.; Varlamova, L.V.; Alovyainikov, A.A.

1982-11-20

220

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

221

Effect of hydrophilically functionalized carbon nanotubes on the reinforcement of water-borne epoxy resin.  

PubMed

Multi-walled carbon nanotubes (MWNTs) were modified covalently with hydrophilic polyacrylic acid (PAA) oligomer. Fourier transform infrared (FTIR), thermogravimetric (TG) analysis, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to characterize the modified MWNTs. The solubility of the modified MWNTs in water was determined to be 55.6 mg/mL by UV/vis spectroscopy. They could be dispersed homogeneously in water-borne epoxy resin and improve the mechanical properties of the resin significantly. The reinforcing ability of the modified MWNTs should be contributed by the fine dispersion of the MWNTs in resin matrix and the robust covalent binding formed by the carbon nanotube-bound carboxylic acid and epoxy groups in the resin. PMID:21770160

Mao, Zhiqing; Wu, Wei; Cheng, Yuan; Xie, Chen; Zhang, Dunming; Jiang, Xiqun

2011-06-01

222

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

223

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

224

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

Code of Federal Regulations, 2010 CFR

...isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified in paragraph...conditions. (a) The resins are produced by the condensation of xylene-formaldehyde resin and 4,4?-isopropylidenediphenol-epichlorohydrin...di-, or trimethylol phenol and capryl alcohol...

2010-04-01

225

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

226

Synthesis of Vinyl Ester Resins in the Presence of Monoepoxies: A Kinetic Study  

Microsoft Academic Search

The synthesis of vinyl ester resins V1, V2, and V3 was carried out using bisphenol-A–based epoxy resin and acrylic acid in presence of phenyl, cresyl, butyl, and glycidyl ethers, respectively, as reactive diluent and triphenylphosphine as catalyst. The reaction was performed at 70°, 75°, 80°, 85°, and 90°C and it followed the first-order kinetics. The specific rate constants, calculated by

Neelam Pal; Akanksha Srivastava; J. S. P. Rai

2003-01-01

227

Management of Spent Organic Ion-Exchange Resins by Photochemical Oxidation  

Microsoft Academic Search

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

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

2003-01-01

228

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

229

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

230

Resin glycosides from the flowers of Ipomoea murucoides.  

PubMed

The CHCl(3)-soluble extract from the flowers of the Mexican medicinal plant Ipomoea murucoides, through preparative-scale recycling HPLC, yielded murucoidins I-V (1-5), which are new pentasaccharides of jalapinolic acid, as well as the known stoloniferin I (6). Saponification of the crude resin glycoside mixture yielded two glycosidic acids, simonic acid B (9) and operculinic acid A (10), and their esterifying residues were composed of the two short-chain fatty acids, 2-methylpropanoic and (2S)-methylbutyric acids. All the isolated compounds (1-6) were characterized through high-field NMR spectroscopy. Compound 4 exhibited marginal cytotoxicity against Hep-2 cells (ED(50) 4 microg/mL). PMID:16643033

Chérigo, Lilia; Pereda-Miranda, Rogelio

2006-04-01

231

Improved Fire-Resistant Resins for Laminates  

NASA Technical Reports Server (NTRS)

Fire-resistant resins for fabricating laminates with inorganic fibers, especially graphite fibers, are formed from bisimides containing main-chain phosphorus and olefinic end groups. Bisimides are thermally polymerized to form resins and laminates virtually imcombustible in pure oxygen at 300 degrees C. New resins are suitable for many applications requiring good adhesion and excellent resistance to heat, fire, solvents and chemicals.

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

1982-01-01

232

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...

233

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

234

Interphase mobility and migration of hydrophobic organic metal extractant molecules in solvent-impregnated resins  

Microsoft Academic Search

Solvent-impregnated resins (SIRs) were made from polyvinyl pyridine and polyvinyl benzyl ammonium types of ionic polymers by impregnation of thiophosphoric acid type extractants. Morphological and nuclear magnetic resonance (NMR) studies were performed to observe the physical migration of the extractants under variation of two chemical factors: acidity and metal concentration. Morphological (surface area) measurements of the SIR-type polymer reveal surface

Abraham Warshawsky; Alex G. Strikovsky; Mark Y. Vilensky; Karel Jerabek

2002-01-01

235

DISPOSAL OF LIQUID WASTE IN THE RESIN-IN-PULP-TYPE URANIUM MILLING FLOWSHEET  

Microsoft Academic Search

Stream and ground water pollution from radioactive nuclides, principally ; radium-228 and thorium-230, in liquid wastes from U mills can be minimized by ; reusing the waste solution within the mill. Such reuse of waste solution in an ; acid leach-resin-in-pulp flowsheet was investigated. The process consists of ; acid leaching for dissolution of the U, sand-slime separation and countercurrent

K. E. Tame; J. B. Rosenbaum

1962-01-01

236

Glycoprotein Enrichment Resin User Manual  

E-print Network

buffer containing either Tris or sorbitol. Specific Enrichment of Glycoproteins Glycoprotein Enrichment Enrichment Resin· Other User Manual (PT4050-1)· Visit our Protein Expression and Purification product pages at www.clontech.com for a current list of products available for protein research. #12;Glycoprotein

Lebendiker, Mario

237

Color Improvement of Petroleum Resin \\  

Microsoft Academic Search

A reaction of thermal-cracked higher fractions obtained from petroleum naptha with maleic anhydride gives a raw material affording a lighter color petroleum resin of 6 G than ordinarily produced one of 11 to 12 G, measured by Gardner scale. Then, some color components which were not yet reported, removed by the reaction, have been identified from the reaction products to

Yoshiyuki Iwase

1979-01-01

238

A new functionalized resin and its application in preconcentration system with multivariate optimization for nickel determination in food samples  

Microsoft Academic Search

In this work, Amberlite XAD-2 resin functionalized with 4,5-dihydroxy-1,3-benzenedisulfonic acid was synthesized, characterized and applied as a new packing material for an on-line system to nickel preconcentration. The method is based on the sorption of Ni(II) ions in a minicolumn containing the synthesized resin, posterior desorption using an acid solution and measurement of the nickel by spectrophotometry (PAR method). The

Valfredo Azevedo Lemos; Patrícia Xavier Baliza; Juracir Silva Santos; Luana Sena Nunes; Adriana Alves de Jesus; Marcelo Eça Rocha

2005-01-01

239

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

240

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

241

An investigation of the applicability of the new ion exchange resin, Reillex{trademark}-HPQ, in ATW separations. Milestone 4, Final report  

SciTech Connect

The investigations with the anion exchange resin Reillex{trademark}-HPQ is continuing along several different paths. The topics of current investigations that are reported here are: The sorption behavior of chromium(VI) on Reillex{trademark}-HPQ from nitric acid solutions and from sodium hydroxide/sodium nitrate solutions; sorption behavior of F{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; sorption behavior of Cl{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; sorption behavior of Br{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; and the Honors thesis by one of the students is attached as Appendix II (on ion exchange properties of a new macroperous resin using bromide as the model ion in aqueous nitrate solutions).

Ashley, K.R.; Ball, J.; Grissom, M.; Williamson, M.; Cobb, S.; Young, D.; Wu, Yen-Yuan J.

1993-09-07

242

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

243

Properties of resorcinol-tannin-formaldehyde copolymer resins prepared from the bark extracts of Taiwan acacia and China fir.  

PubMed

Resorcinol-tannin-formaldehyde copolymer resins (RTF) were prepared by using the bark extracts of Taiwan acacia (Acacia confusa) and China fir (Cunninghamia lanceolata) to substitute part of the resorcinol. From the results, the content of reactive phenolic materials in Taiwan acacia and China fir bark extracts were 51.6% and 46.5%, respectively. Aromatic compounds were the main components in the bark extracts showed by FT-IR analysis. The conventional synthesis condition used for RF resin was certainly not suitable for the RTF copolymer resin. It should be formed the novolak RF prepolymer by reacting the resorcinol with formaldehyde at the first stage, and then the bark extracts added and underwent the copolymerization reaction under acidic condition at the second-stage. The RTF copolymer resins prepared had cold-setting capability. They had higher viscosity, shorter gel time as compared with the RF resin. The RTF copolymer resins could be carried out the gluing application immediately after the hardener was added and had bonding strength the same as RF resin. But the RTF copolymer resins had worse stability and shorter shelf life than RF resin. PMID:16171683

Lee, Wen-Jau; Lan, Wei-Chuan

2006-01-01

244

Extraction of high quality DNA from seized Moroccan cannabis resin (Hashish).  

PubMed

The extraction and purification of nucleic acids is the first step in most molecular biology analysis techniques. The objective of this work is to obtain highly purified nucleic acids derived from Cannabis sativa resin seizure in order to conduct a DNA typing method for the individualization of cannabis resin samples. To obtain highly purified nucleic acids from cannabis resin (Hashish) free from contaminants that cause inhibition of PCR reaction, we have tested two protocols: the CTAB protocol of Wagner and a CTAB protocol described by Somma (2004) adapted for difficult matrix. We obtained high quality genomic DNA from 8 cannabis resin seizures using the adapted protocol. DNA extracted by the Wagner CTAB protocol failed to give polymerase chain reaction (PCR) amplification of tetrahydrocannabinolic acid (THCA) synthase coding gene. However, the extracted DNA by the second protocol permits amplification of THCA synthase coding gene using different sets of primers as assessed by PCR. We describe here for the first time the possibility of DNA extraction from (Hashish) resin derived from Cannabis sativa. This allows the use of DNA molecular tests under special forensic circumstances. PMID:24124454

El Alaoui, Moulay Abdelaziz; Melloul, Marouane; Alaoui Amine, Sanaâ; Stambouli, Hamid; El Bouri, Aziz; Soulaymani, Abdelmajid; El Fahime, Elmostafa

2013-01-01

245

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

246

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

247

Petroleum resins and their production  

SciTech Connect

A process is described for the production of petroleum resins compatible with base polymers in hot melt formulations and having a softening point of from about 60/sup 0/C. to about 120/sup 0/C. and Gardner color of about 4 or less, comprising copolymerizing using a Friedel-Crafts catalyst. The mixture is substantially free form cyclopentadiene and dicyclopentadiene. This patent also describes a resin consisting essentially of a copolymer containing from 5 to 80 wt. % of units derived from an olefinically unsaturated aromatic compound form 5 to 80 wt. % of units derived from C/sub 5/ olefines or diolefines or C/sub 6/ olefines diolefines or a mixture of C/sub 5/ and C/sub 6/ olefines or diolefines and from 7 to 45 wt. % of units derived from a terpene.

Luvinh, Q.

1989-04-25

248

Recovery of sulphuric acid from waste aqueous solutions containing arsenic by ion exchange  

Microsoft Academic Search

Laboratory scale experiments with anion and cation exchange resins aiming to separate arsenic from highly acidic, sulphate-containing solutions were carried out. The data obtained proved that the use of strong acid cation exchangers in the Na form gives the opportunity for arsenic\\/acid separation in two stages. During the period of sulphuric acid accumulation (a period in which the resin is

V. Nenov; N. Dimitrova; I. Dobrevsky

1997-01-01

249

Pharmaceutical Applications of Ion-Exchange Resins  

NASA Astrophysics Data System (ADS)

The historical uses of ion-exchange resins and a summary of the basic chemical principles involved in the ion-exchange process are discussed. Specific applications of ion-exchange resins are provided. The utility of these agents to stabilize drugs are evaluated. Commonly occurring chemical and physical incompatibilities are reviewed. Ion-exchange resins have found applicability as inactive pharmaceutical constituents, particularly as disintegrants (inactive tablet ingredient whose function is to rapidly disrupt the tablet matrix on contact with gastric fluid). One of the more elegant approaches to improving palatability of ionizable drugs is the use of ion-exchange resins as taste-masking agents. The selection, optimization of drug:resin ratio and particle size, together with a review of scaleup of typical manufacturing processes for taste-masked products are provided. Ion-exchange resins have been extensively utilized in oral sustained-release products. The selection, optimization of drug:resin ratio and particle size, together with a summary of commonly occurring commercial sustained-release products are discussed. Ion-exchange resins have also been used in topical products for local application to the skin, including those where drug flux is controlled by a differential electrical current (ionotophoretic delivery). General applicability of ion-exchange resins, including ophthalmic delivery, nasal delivery, use as drugs in their own right (e.g., colestyramine, formerly referred to as cholestyramine), as well as measuring gastrointestinal transit times, are discussed. Finally, pharmaceutical monographs for ion-exchange resins are reviewed.

Elder, David P.

2005-04-01

250

The influence of plutonium concentration and solution flow rate on the effective capacity of macroporous anion exchange resin. [Lewatit MP-500-FK; Pu/sup +/  

SciTech Connect

The principal aqueous process used to recover and purify plutonium at the Los Alamos Plutonium Facility is anion exchange in nitric acid. Previous studies with gel-type anion exchange resin have shown an inverse relationship between plutonium concentration in the feed solution and the optimum flow rate for this process. Because gel-type resin has been replaced with macroporous resin at Los Alamos, the relationship between plutonium concentration and solution flow rate was reexamined with the selected Lewatit MP-500-FK resin using solutions of plutonium in nitric acid and in nitric acid with high levels of added nitrate salts. Our results with this resin differ significantly from previous data obtained with gel-type resin. Flow-rate variation from 10 to 80 liters per hour had essentially no effect on the measured quantities of plutonium sorbed by the macroporous resin. However, the effect of plutonium concentration in the feed solutions was pronounced, as feed solutions that contained the highest concentrations of plutonium also produced the highest resin loadings. The most notable effect of high concentrations of dissolved nitrate salts in these solutions was an increased resin capacity for plutonium at low flow rates. 16 refs., 7 figs., 2 tabs.

Marsh, S.F.; Gallegos, T.D.

1987-07-01

251

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

252

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

253

Seasonal variation and resin composition in the Andean tree Austrocedrus chilensis.  

PubMed

Little is known about the changes in resin composition in South American gymnosperms associated with the different seasons of the year. The diterpene composition of 44 resin samples from seven Austrocedrus chilensis (Cupressaceae) trees, including male and female individuals, was investigated in three different seasons of the year (February, June and November). Twelve main diterpenes were isolated by chromatographic means and identified by gas chromatography-mass spectrometry and nuclear magnetic resonance (NMR). The diterpene composition was submitted to multivariate analysis to find possible associations between chemical composition and season of the year. The principal component analysis showed a clear relation between diterpene composition and season. The most characteristic compounds in resins collected in summer were Z-communic acid (9) and 12-oxo-labda-8(17),13E-dien-19 oic acid methyl ester (10) for male trees and 8(17),12,14-labdatriene (7) for female trees. For the winter samples, a clear correlation of female trees with torulosic acid (6) was observed. In spring, E-communic acid (8) and Z-communic acid (9) were correlated with female trees and 18-hydroxy isopimar-15-ene (1) with male tree resin. A comparison between percent diterpene composition and collection time showed p < 0.05 for isopimara-8(9),15-diene (2), sandaracopimaric acid (4), compound (7) and ferruginol (11). PMID:24853713

Olate, Verónica Rachel; Soto, Alex; Schmeda-Hirschmann, Guillermo

2014-01-01

254

Ether-soluble resin glycosides from the roots of Ipomoea batatas.  

PubMed

Two new resin glycosides, batataosides I (1) and II (2), and five known compounds, friedelin (3), scopoletin (4), octadecyl caffeate (5), beta-sistosterol (6) and daucosterol (7), were isolated from the roots of Ipomoea batatas. Their structures have been determined based on the chemical and spectral data. Batataosides I and II have novel structures because the core simonic acid B was esterised with cinnamic acid for the first time, and three different substituent esterification groups in one resin glycoside is scarce. The absolute configuration of the aglycone was elucidated to be S by Mosher's method. PMID:18335340

Yin, Yong-Qin; Kong, Ling-Yi

2008-01-01

255

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

256

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

257

New modified hydrocarbon resins; An alternative to styrenated terpene resins in hot melts  

SciTech Connect

This paper reports on the development of two hydrocarbon-based resin formulations that could be used with different thermoplastic block copolymers to formulate pressure-sensitive adhesives. Results are examined with one of these resins in formulations with styrene-isoprene-styrene (SIS) and styrene-butadiene (SB) compounds. The new modified hydrocarbon resin, with a softening point of 98{degrees} C, matches the adhesive performance of a terpene resin with a softening point of 105{degrees} C. The resin performs as well as the modified terpene in SIS-, SB-, and EVA-based adhesives. The new hydrocarbon resin is especially well suited for hot-melt adhesives. It exhibits low volatility, good color stability, and excellent melt viscosity stability. Since the new resin is based on petroleum hydrocarbon feedstocks, it should be available at moderate, stable prices. The other hydrocarbon resin, with a softening point of 85{degrees} C, produced comparable results.

Carper, J.D. (Hercules Inc., Wilmington, DE (US))

1990-06-01

258

Porous Ceramic Spheres from Ion Exchange Resin  

NASA Technical Reports Server (NTRS)

A commercial cation ion exchange resin, cross-linked polystyrene, has been successfully used as a template to fabricate 20 to 50 micron porous ceramic spheres. Ion exchange resins have dual template capabilities. Pore architecture of the ceramic spheres can be altered by changing the template pattern. Templating can be achieved by utilizing the internal porous structure or the external surface of the resin beads. Synthesis methods and chemical/physical characteristics of the ceramic spheres will be reported.

Dynys, Fred

2005-01-01

259

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

260

Complexing properties of Diphonix, a new chelating resin with diphosphonate ligands, toward Ga(III) and In(III)  

SciTech Connect

The complexing properties of Diphonix, a new chelating ion-exchange resin, toward indium and gallium cations was investigated. Variables included bead size, contact time, solution pH, and the presence of competing cations. The resin, which contains diphosphonic acid ligands, displayed rapid rates of complexation and high selectivity under acidic conditions. Metal uptake from 1 M sulfuric acid solution under continuous flow conditions was 0.47 mmol/g (33.0 mg/g) for gallium and 0.76 mmol/g (87.8 mg/g) for indium. The resin may be regenerated by elution with 1-hydroxyethane-1,1-diphosphonic acid or hydrochloric acid. 11 refs., 5 figs.

Trochimczuk, A.W.; Alexandratos, S.D. (Univ. of Tennessee, Knoxville, TN (United States)); Horwitz, E.P. (Argonne National Lab., IL (United States))

1994-02-01

261

Interferometric study of epoxy resin gelation  

SciTech Connect

The transition of epoxy resins from a mobile liquid to a rubbery gel is a complex process depending on chemical reaction kinetics and both heat and mass transfer. The purpose of this study is to determine the locus of initial gelation in an epoxy resin, and the course of gelatin through both neat resins and glass fiber/epxoy resin composites. This was accomplished by monitoring the local changes in refractive index in transparent epoxy castings using laser interferometry, supplemented by temperature profiles obtained from thermocouple arrays. These experiments were carried out on pure DGEBA epoxy (DOW DER-332) cured with a variety of primary amine, secondary amine, and anhydride curing agents.

Hirschbuehler, K.R.

1981-01-01

262

Characterization of PMR polyimide resin and prepreg  

NASA Technical Reports Server (NTRS)

Procedures for the chemical characterization of PMR-15 resin solutions and graphite-reinforced prepregs were developed, and a chemical data base was established. In addition, a basic understanding of PMR-15 resin chemistry was gained; this was translated into effective processing procedures for the production of high quality graphite composites. During the program the PMR monomers and selected model compounds representative of postulated PMR-15 solution chemistry were acquired and characterized. Based on these data, a baseline PMR-15 resin was formulated and evaluated for processing characteristics and composite properties. Commercially available PMR-15 resins were then obtained and chemically characterized. Composite panels were fabricated and evaluated.

Lindenmeyer, P. H.; Sheppard, C. H.

1984-01-01

263

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

264

Sand control with resin and explosive  

SciTech Connect

This patent describes a method for treating a well having perforated casing to prevent solids movement through the perforations and into the wellbore. It comprises positioning a quantity of liquid resin solution such that the solution occupies the interval of the casing having perforations; positioning an explosive in proximity with the liquid resin solution; detonating the explosive; displacing the liquid resin solution remaining in the wellbore after step (c) through the perforations with a displacing fluid; and injecting a chemical solution through the perforations to cause the resin to polymerize to form a consolidated permeable matrix.

Dees, J.M.; Begnaud, W.J.; Sahr, N.L.

1992-09-08

265

Resin flow analysis with fiber preform deformation in through thickness direction during Compression Resin Transfer Molding  

Microsoft Academic Search

Resin flow during Compression Resin Transfer Molding (CRTM) can be best described and analyzed in three phases. In the first phase, a gap is created by holding the upper mold platen parallel to the preform surface at a fixed distance from it. The desired amount of resin injected into the gap quickly flows primarily over the preform. The second phase

Justin Merotte; Pavel Simacek; Suresh G. Advani

2010-01-01

266

Failure load of acrylic resin denture teeth bonded to high impact acrylic resins  

Microsoft Academic Search

Statement of problem. Techniques for bonding denture teeth to an acrylic resin denture base remain empirical, with little consensus from the literature, among clinicians, or among dental laboratories. Purpose. This study evaluated the failure load of acrylic resin teeth bonded to 2 high impact acrylic resins. Methods and material. The ridge lap portion on 120 identical denture teeth were modified

Donna Barpal; Donald A. Curtis; Frederick Finzen; Jovin Perry; Stuart A. Gansky

1998-01-01

267

Product forms and packaging in the fatty acid industry  

Microsoft Academic Search

tion. Dimer acids are used in the synthesis of polyester resins of improved flexibility; e.g., in oilless alkyds used in coil coatings. Other applications are in hot melt adhesive polyester resins, and in surface coatings based on oilmodified alkyds, epoxy esters or urethanes. Esters of dimer acids are used in modern industrial lubricants and metal-working compounds to provide both lubrication

J. A. Rauch

1979-01-01

268

Synthesis of perrhenic acid using ion exchange method  

Microsoft Academic Search

The paper presents results of the study for obtaining perrhenic acid from aqueous ammonium perrhenate solutions by ion exchange. Two ways of perrhenic acid synthesis have been examined: sorption of perrhenate anion on selected anion exchange resins (followed by elution of the sorbed rhenium as HReO4), and sorption of ammonium ion on selected cation exchange resins. The method of ammonium

K. Leszczy?ska-Sejda; G. Benke; A. Chmielarz; S. Krompiec; S. Michalik; M. Krompiec

2007-01-01

269

75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan  

Federal Register 2010, 2011, 2012, 2013

...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

270

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2012-07-01

271

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2011-07-01

272

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2013-07-01

273

40 CFR 721.4380 - Modified hydrocarbon resin.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified hydrocarbon resin. 721.4380 Section 721...Substances § 721.4380 Modified hydrocarbon resin. (a) Chemical substance...identified generically as a modified hydrocarbon resin (P-91-1418) is...

2010-07-01

274

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

2012-04-01

275

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

2013-04-01

276

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

2011-04-01

277

21 CFR 177.2510 - Polyvinylidene fluoride resins.  

...2014-04-01 2014-04-01 false Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

2014-04-01

278

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 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...

2013-04-01

279

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

280

21 CFR 872.3770 - Temporary crown and bridge resin.  

...2014-04-01 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...

2014-04-01

281

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2012-04-01

282

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 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...

2011-04-01

283

Sulfonated Petroleum Polymeric Resins as Plasticizers for Cement Mortars  

Microsoft Academic Search

Sulfonation of petroleum polymeric resins based on the C9 fraction with various suilfonatic agents was studied, and procedure was developed for preparing sulfonated resins. The possibility of using sulfo resins as effective plasticizers for concrete was examined.

V. P. Lesnyak; L. V. Gaponik; V. P. Mardykin; F. N. Kaputskii

2003-01-01

284

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

285

Complexation of metal ion with poly(1-vinylimidazole) resin prepared by radiation-induced polymerization with template metal ion. [Gamma radiation  

SciTech Connect

Poly(1-vinylimidazole) (PVI) resin was prepared with Ni/sup 2 +/, CO/sup 2 +/, or Zn/sup 2 +/ as a template to study the adsorption of metal ions. The metal-1-vinylimidazole complex was copolymerized and cross-linked with 1-vinyl-2-pyrrolidone by ..gamma..-ray irradiation and the template metal ion was removed by treating the polymer complex with an acid. These PVI resins adsorbed metal ions more effectively than the PVI resin prepared without the template. The number of adsorption sites (As) and the stability constant (K) of Ni/sup 2 +/ complex were larger for the PVI resin prepared with the Ni ion template caused by the smaller dissociation rate constant of Ni ion from the resin. The composition of the Ni/sup 2 +/ complex in the resin remained constant. This suggests that the complexation proceeded via a one-step mechanism.

Kato, M. (Waseda Univ., Tokyo, Japan); Nishide, H.; Tsuchida, E.; Sasaki, T.

1981-07-01

286

Development of solvent-free offset ink using vegetable oil esters and high molecular-weight resin.  

PubMed

In the development of solvent-free offset ink, the roles of resin molecular weight and used solvent on the ink performance were evaluated by examining the relationship between the various properties of resin and solvent and print quality. To find the best performing resin, the soy-oil fatty acid methyl ester (FAME) was applied to the five modified-phenolic resins having different molecular weights. It is found from the experimental results that the ink made of higher molecular weight and better solubility resin gives better printability and print quality. It is because larger molecular weight resin with better solubility gives higher rate of ink transfer. From the ink application of different esters to high molecular weight resin, the best printing performance was yielded from the soy-oil fatty acid butyl ester (FABE). It is due to its high kinematic viscosity resulting in the smallest change of ink transfer weight upon multiple number of printing, which improves the stability of ink quality. PMID:23728325

Park, Jung Min; Kim, Young Han; Kim, Sung Bin

2013-01-01

287

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

288

Preconcentration of Cu (II) from seawater using a novel and stable phenol-formaldehyde resin.  

PubMed

Preconcentration of Cu (II) from seawater using a novel phenol-formaldehyde (P-F) resin was investigated. 1,2-dihydroxybenzene-4-azo-3-hydroxybenzene-formaldehyde resin (DAHBF) was prepared by condensing 1,2-dihydroxybenzene-4-azo-3-hydroxybenzene with formaldehyde (1:2 mole ratio) in the presence of oxalic acid as catalyst. Polychelates were obtained when the DAHBF was treated with the aqueous solution of Cu (II) ions. The polymeric resin and polymer-metal complexes were characterized with thermal analysis and spectral studies. The IR spectra of polychelates suggest that the metal was coordinated through the oxygen atoms of the dihydroxybenzene moiety. The TGA data revealed the thermal stability of the resin and the polychelates. X-ray diffraction study revealed the incorporation of the metal ion significantly enhanced the degree of crystallinity. The sorption properties of the chelate forming resin towards divalent metal ion [Cu(II)] was studied as a function of pH, preconcentration time, metal concentration, amount of resin, aqueous phase volume and presence of electrolyte. This procedure was validated for recovery of copper from seawater samples. The method has adequate accuracy and it can be used for determination of copper in sea water samples. PMID:20371945

Manivannan, D; Starvin, Maria; Biju, V M

2010-01-01

289

21 CFR 177.1500 - Nylon resins.  

...ibr_locations.html. (ii) The viscosity number (VN) for Nylon 6/69 and Nylon PA-6-3-T resins in a 99 percent cresol solution (5 milligrams resin per milliliter) shall be determined at 25 °C (77 °F) by method ISO...

2014-04-01

290

Ethynyl-Containing Aromatic Polyamide Resins.  

National Technical Information Service (NTIS)

In accordance with the present invention there is provided a novel aromatic polyamide resin having repeating units, each containing at least one o-ethynyl amido subunits. The resins of this invention which contain the above subunit can be thermally treate...

R. C. Evers

1985-01-01

291

Fluorinated diamond bonded in fluorocarbon resin  

SciTech Connect

By fluorinating diamond grit, the grit may be readily bonded into a fluorocarbon resin matrix. The matrix is formed by simple hot pressing techniques. Diamond grinding wheels may advantageously be manufactured using such a matrix. Teflon fluorocarbon resins are particularly well suited for using in forming the matrix.

Taylor, Gene W. (Los Alamos, NM)

1982-01-01

292

Fluorinated diamond bonded in fluorocarbon resin  

SciTech Connect

By fluorinating diamond grit, the grit may be readily bonded into a fluorocarbon resin matrix. The matrix is formed by simple hot pressing techniques. Diamond grinding wheels may advantageously be manufactured using such a matrix. Teflon fluorocarbon resins are particularly well suited for using in forming the matrix.

Taylor, G.W.

1982-08-10

293

Novel process of isolating novolac resin fractions  

NASA Astrophysics Data System (ADS)

Typical phenol/formaldehyde resin syntheses generate a broad distribution of molecular weight fragments with a wide polydispersity. A process was developed to isolate novolak resin fractions of narrow polydispersity from phenol- formaldehyde condensation products in ethyl lactate without any high temperature distillation. The characterization and the performance of these fractions in i-line photoresist composition are discussed.

Rahman, M. D.; Lu, Ping-Hung; Cook, Michelle M.

1997-07-01

294

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

295

Chemical affinities between the solvent extractable and the bulk organic matter of fossil resin associated with an extinct podocarpaceae  

USGS Publications Warehouse

Analyses by GC-MS and GC-IR of resin associated to Dacridiumites mawsonii deposits, an extinct species of Podocarpaceae occurring on the South Island of New Zealand during the Bortonian (Middle Eocene), have revealed that dehydroabietic acid is the predominant component of the solvent soluble fraction. Accordingly, this diterpenoid has been selected as the principal component material for spectroscopic comparison with the bulk resin using IR and CP/MAS 13C NMR. ?? 1989.

Grimalt, J.O.; Simoneit, B.R.T.; Hatcher, P.G.

1989-01-01

296

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

297

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

298

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

299

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

300

New affinity resin for purification of cap-binding proteins.  

PubMed

Cap binding proteins, which recognize the cap structure present at 5' termini of RNA polymerase II transcripts, have been routinely isolated and purified using affinity resins with mononucleotide cap analogs attached. Here we present a new methodology in which dinucleotide cap analog, m7GpppG, has been linked to the EAH-Sepharose. The method is based on derivatization of 2',3'-cis diol of the second nucleotide within the cap structure, with levulinic acid, and subsequent coupling of resulted acetal through its carboxylic group with aminohexyl-agarose. PMID:16247979

Jankowska-Anyszka, Marzena; Nogalski, Maciej; Darzynkiewicz, Edward

2005-01-01

301

Solidification of ion exchange resin wastes  

SciTech Connect

Solidification media investigated included portland type I, portland type III and high alumina cements, a proprietary gypsum-based polymer modified cement, and a vinyl ester-styrene thermosetting plastic. Samples formulated with hydraulic cement were analyzed to investigate the effects of resin type, resin loading, waste-to-cement ratio, and water-to-cement ratio. The solidification of cation resin wastes with portland cement was characterized by excessive swelling and cracking of waste forms, both after curing and during immersion testing. Mixed bed resin waste formulations were limited by their cation component. Additives to improve the mechanical properties of portland cement-ion exchange resin waste forms were evaluated. High alumina cement formulations dislayed a resistance to deterioration of mechanical integrity during immersion testing, thus providing a significant advantage over portland cements for the solidification of resin wastes. Properties of cement-ion exchange resin waste forms were examined. An experiment was conducted to study the leachability of /sup 137/Cs, /sup 85/Sr, and /sup 60/Co from resins modified in portland type III and high alumina cements. The cumulative /sup 137/Cs fraction release was at least an order of magnitude greater than that of either /sup 85/Sr or /sup 60/Co. Release rates of /sup 137/Cs in high alumina cement were greater than those in portland III cement by a factor of two.Compressive strength and leach testing were conducted for resin wastes solidified with polymer-modified gypsum based cement. /sup 137/Cs, /sup 85/Sr, and /sup 60/Co fraction releases were about one, two and three orders of magnitude higher, respectively, than in equivalent portland type III cement formulations. As much as 28.6 wt % dry ion exchange resin was successfully solidified using vinyl ester-styrene compared with a maximum of 25 wt % in both portland and gypsum-based cement.

Not Available

1982-08-01

302

The Separation of Beryllium from Selected Elements Using the Dipex Extraction Chromatographic Resin  

Microsoft Academic Search

An extraction chromatographic resin containing the acidic chelating organophosphorus extractant, Dipex, sorbed onto an inert polymeric substrate has been evaluated for the separation of beryllium from a wide range of elements. The elements selected comprise those which can interfere with the determination of beryllium by inductively coupled plasma?atomic emission spectroscopy (ICP?AES) and matrix elements which commonly occur in environmental and

E. Philip Horwitz; Daniel R. McAlister

2005-01-01

303

Effects of resin hydrophilicity on water sorption and changes in modulus of elasticity  

Microsoft Academic Search

As acidic monomers of self-etching adhesives are incorporated into dental adhesives at high concentrations, the adhesive becomes more hydrophilic. Water sorption by polymers causes plasticization and lowers mechanical properties. The purpose of this study was to compare the water sorption and modulus of elasticity (E) of five experimental neat resins (EX) of increasing hydrophilicity, as ranked by their Hoy's solubility

Shuichi Ito; Masanori Hashimoto; Bakul Wadgaonkar; Nadia Svizero; Ricardo M. Carvalho; Cynthia Yiu; Frederick A. Rueggeberg; Stephen Foulger; Takashi Saito; Yoshihiro Nishitani; Masahiro Yoshiyama; Franklin R. Tay; David H. Pashley

2005-01-01

304

Fabrication and Mechanical Characterization of Water-Soluble Resin-Coated Natural Fiber Green Composites  

Microsoft Academic Search

In this study, water-soluble biodegradable resin was introduced as a coating agent to improve the interfacial strength and then to fabricate a high-performance green composite with polylactic acid (PLA) and hemp yarn. Dip coating was carried out for hemp yarn and the green composites were fabricated by hot processing. The coated green composite achieves a high tensile strength of 117

Ken-Ichi Manabe; Tomoyuki Hayakawa

2009-01-01

305

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

306

Oxidative degradation of 2,6-dibromophenol using anion-exchange resin supported supramolecular catalysts of iron(III)-5,10,15,20-tetrakis (p-hydroxyphenyl)porphyrin bound to humic acid prepared via formaldehyde and urea-formaldehyde polycondensation.  

PubMed

An iron(III)-porphyrin catalyst, iron(III)-tetrakis(p-hydroxyphenyl)porphyrin (FeTHP), was introduced into a humic acid via a formaldehyde or urea-formaldehyde polycondensation reaction to stabilize the catalyst. The prepared supramolecular catalysts were then attached to Dowex-22, an anion-exchange resin. The oxidation of 2,6-dibromophenol (2,6-DBP) was then used, to evaluate the catalytic activities of the supported catalysts. The supported catalyst prepared via the urea-formaldehyde polycondensation reaction showed the highest catalytic activity of all catalysts tested. However, no debromination was observed under any conditions. To examine the reusability of the supported catalysts, they were evaluated on the basis of the decrease in the percent degradation of 2,6-DBP for the number times that they could be used. To determine why the catalytic activities decreased with increasing use, the surface of the supported catalysts were observed by scanning electron microscopy and energy dispersive X-ray spectrometry (SME-EDS) after each use. The poor reusability of the supported catalysts can be attributed to the fact that 2,6-DBP and/or brominated byproducts are tightly absorbed to the catalyst in the vicinity of the active site, which leads to inactivation of the supported catalysts. PMID:20721797

Shigetatsu, Satoko; Fukushima, Masami; Nagao, Seiya

2010-10-01

307

Impact of curing condition on pH and alkalinity\\/acidity of structural wood adhesives  

Microsoft Academic Search

Nine formulations were selected for evaluating the effect of different curing methods on pH and alkalinity or acidity of various structural wood adhesives. These included four phenol–formaldehyde (PF) resins with high pH, one phenol–resorcinol–formaldehyde (PRF) resin with intermediate pH, two melamine–urea–formaldehyde (MUF) resins, and two melamine–formaldehyde (MF) resins with low pH. The four curing methods used in the study were:

Yaolin Zhang; Xiang-Ming Wang; Romulo Casilla; Paul Cooper; Zeen Huang; Xiaodong Wang

2010-01-01

308

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

309

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

310

Modification of Malonamide Ion-Exchange\\/Chelating Resins Using the Fields–Kabatschnik Reaction and Their Application to Metal Ion Removal from Aqueous Solutions  

Microsoft Academic Search

A resin containing 2-aminoethyl-substituted amides of malonic acid was modified in the Fields–Kabatschnik reaction using diethyl phosphite. The resultant ion-exchange\\/chelating resins have aminomethylphosphonate groups. Modification proceeds almost quantitatively, giving a resin with P=1.97 mmol\\/g, N=4.20 mmol\\/g, and water regain of 0.44 g\\/g. It can be selectively hydrolyzed by treatment with trimethylchlorosilane\\/potassium bromide in dry acetonitrile. Both acidic and ester forms

Andrzej W. Trochimczuk; Julia Jezierska

2000-01-01

311

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

312

Alkyd–amino resins based on waste PET for coating applications  

Microsoft Academic Search

Waste polyethylene terephthalate (PET) flakes were depolymerized by using propylene glycol (PG) in the presence of zinc acetate as catalyst. Glycolysis reaction products of waste PET obtained by using PET\\/glycol molar ratio 1\\/2. Two short oil alkyd resins of high acid values (30–40mgKOH\\/g) were prepared from phthalic anhydride (PA), glycerin (G), coconut oil fatty acids (COFA) and glycolyzed products of

A. Torlako?lu; G. Gueclue

2009-01-01

313

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

314

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

315

Removing Aquatic Organic Substances by Anion Exchange Resins  

Microsoft Academic Search

The focus of this study was verification of the mechanisms of removal of aquatic organic substances by anion exchange resins, influence of resin properties and clarification processes on removal, and Chromatographie behavior of organic substances in anion exchange columns. Depending on the type of resin and the nature of the organic matter, anion exchange resins removed up to 80 percent

Paul L. K. Fu; James M. Symons

1990-01-01

316

Microleakage at the resin-alloy interface of chemically retained composite resins for cast restorations.  

PubMed

New retentive mechanisms between veneering resins and casting alloys are claimed to have a chemical bond that results in a high bond strength combined with low microleakage between the veneering resin and cast restoration. This study compared the microleakage of four chemical bonding mechanisms when three veneering resins were bonded to two dental casting alloys. Resin-veneered alloy disks were immersed in red India ink and kept at 37 degrees C for 72 hours. The disks were then bench dried for 24 hours. The resin veneer was sectioned into eight sectors in an engineering milling machine and these resin sectors were removed to display the microleakage pattern. It was concluded that (1) no microleakage was found in two combinations, and (2) the highest microleakage was with Sr-Isosit-N/Panavia EX/Firmilay combinations. PMID:1712849

Strygler, H; Nicholls, J I; Townsend, J D

1991-06-01

317

EP-toxicity test of saturated GT-73 resin and resin in grout  

SciTech Connect

The results of EP-toxicity tests on mercury saturated Duolite{reg sign} GT-73 cation exchange resin clarify options for the ultimate disposal of spent resin. Samples of GT-73 saturated with mercury passed the EP-toxicity test, indicating that fully spent resin may be classifed as solid''-not hazardous''-waste and stored or disposed-of as such. Samples of GT-73 resin saturated with mercury and then incorporated into Portland Type 1 cement did not pass the EP-toxicity test and fall into the hazardous waste'' category. Samples of GT-73 resin less-than-saturated with mercury which were in corporated in Portland Type 1 cement passed the EP-toxicity test and may be classified as solid waste.'' Other commercially available materials are being investigated for incorporating fully spent GT-73 resin in a solid waste form.

Bibler, J.P.

1985-04-24

318

4META Opaque Resin — A New Resin Strongly Adhesive to Nickel-Chromium Alloy  

Microsoft Academic Search

Opaque resins lacking adhesion and mechanical retention devices are required in positioning crowns; the average bond strength in such cases is 60-70 kg\\/cm2. An adhesive opaque resin containing 4-methacryloxyethyl trimellitate anhydride was prepared for use with acrylic veneer crowns, and its bond strength and durability of adhesion with an alloy were studied. Its bonding strength between cured resin and dental

T. Tanaka; K. Nagata; M. Takeyama; M. Atsuta; N. Nakabayashi; E. Masuhara

1981-01-01

319

New modified hydrocarbon resins; An alternative to styrenated terpene resins in hot melts  

Microsoft Academic Search

This paper reports on the development of two hydrocarbon-based resin formulations that could be used with different thermoplastic block copolymers to formulate pressure-sensitive adhesives. Results are examined with one of these resins in formulations with styrene-isoprene-styrene (SIS) and styrene-butadiene (SB) compounds. The new modified hydrocarbon resin, with a softening point of 98° C, matches the adhesive performance of a terpene

Carper

1990-01-01

320

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

321

Curing kinetics of phenol formaldehyde resin and wood-resin interactions in the presence of wood substrates  

Microsoft Academic Search

The curing kinetics of resol PF resin and resin–wood interactions in the presence of wood substrates have been studied by differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The activation energy of cure of PF resin generally increases when PF resin is mixed with wood, mainly due to the decrease of the pH values resulting from the presence

Guangbo He; Bernard Riedl

2004-01-01

322

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

323

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

324

Removal of Trace Contaminants from Water Using New Chelating Resins  

Microsoft Academic Search

The modification of cross?linked polyacrylamide (CPAAm) and incorporation of methyl thiourea (MeTU) or phenyl thiourea (PhTU) group were utilized in the preparation of two new chelating resins CPAAm?EDA?MeTU (resin I) and CPAAM?EDA?PhTU (resin II), [EDA=ethylenediamine]. The prepared resins were characterized by elemental analysis and IR spectroscopy. The sorption behaviors of Cd(II), Pb(II), and Zn(II) ions on the prepared resins were

Mohammed A. Sharaf; Said A. Sayed; Ahmed A. Younis; A. B. Farag; Hassan A. Arida

2007-01-01

325

Nano/microstructured ion exchange resins and their applications.  

PubMed

Ion exchange resins, due to their specific nano/microstructures and applications, have attracted great attention in the past decades. This paper reviews the recent advances and applications of nano/microstructured ion exchange resins, with an introduction to the preparation and property of different ion exchange resins. The applications of different ion exchange resins in catalysts, medicine, metallurgical regeneration, metals, and chemicals removal are summarized and discussed. The perspectives for the future developments of ion exchange resins are also proposed. PMID:24749456

Yu, Bing; Cong, Hailin; Yuan, Hua; Liu, Xuesong; Jiao, Mingming; Wang, Dong

2014-02-01

326

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

327

21 CFR 177.1580 - Polycarbonate resins.  

Code of Federal Regulations, 2011 CFR

...transporting, or holding food, in accordance with the following prescribed conditions: (a) Polycarbonate resins are polyesters produced by: (1) The condensation of 4,4?-iso-propylidenediphenol and carbonyl chloride to which may have...

2011-04-01

328

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2013 CFR

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2013-04-01

329

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 CFR

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2010-04-01

330

21 CFR 177.1585 - Polyestercarbonate resins.  

...regulations/ibr_locations.html. (ii) A minimum weight-average molecular weight of 27,000, as determined by gel permeation chromatography using polystyrene standards. (2) Extractives limitations. The polyestercarbonate resins to be...

2014-04-01

331

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

332

21 CFR 177.1680 - Polyurethane resins.  

...3-Tetramethylbutyl) - phenyl]-omega- hydroxypoly(oxyethylene) (5 moles), average molecular weight 425. Trimethylol propane. (b) Optional adjuvant substances employed in the production of the polyurethane resins or added thereto to impart...

2014-04-01

333

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

334

Certain characteristics of the statics of molybdenum sorption on AV-17P anion-exchange resin with modified structure  

SciTech Connect

The statics of molybdenum sorption by anion exchangers is characterized by the complex interaction of various factors, including not only the chemical structure of the polymeric matrix of the given resin and solution pH, but also the salt composition of the medium, the porosity of the resin, changes of the ionic state of molybdenum in solution, and polymerization of the adsorbed molybdenum ions in the resin structure. The isotherms of molybdenum sorption in alkaline media on anion exchangers are represented by convex curves, but in weakly acidic media ion exchange on modified resins is accompanied by the establishment of false ion-exchange equilibrium on nonporous and fine-grained forms of the sorbents and by changes of the ionic state of molybdenum in the liquid and sorbent phases, depending on the concentration in these phases. This paper elaborates on these process features.

Kholmogorov, A.G.; Il'ichev, S.N.; Kirillova, V.P.

1986-09-10

335

Simultaneous production of high quality biodiesel and glycerin from Jatropha oil using ion-exchange resins as catalysts and adsorbent.  

PubMed

The simultaneous production of high quality biodiesel and glycerin was realized by a bench-scale process using expanded-bed reactors packed with cation- and anion-exchange resins. The mixed-solution of crude Jatropha oil and methanol at a stoichiometric molar ratio was supplied to the process. The free fatty acid as well as triglyceride was completely converted to biodiesel. All by-products were adsorbed on the resin and the effluent from the process was free from them. The effluent fully met the international biodiesel standard specifications without any downstream purification processes except for removing methanol. The glycerin adsorbed on the resin was completely recovered as a transparent methanol solution during regeneration of the resin. PMID:23796424

Shibasaki-Kitakawa, Naomi; Kanagawa, Keiichi; Nakashima, Kazunori; Yonemoto, Toshikuni

2013-08-01

336

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

337

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

338

Fabrication and Mechanical Characterization of Water-Soluble Resin-Coated Natural Fiber Green Composites  

NASA Astrophysics Data System (ADS)

In this study, water-soluble biodegradable resin was introduced as a coating agent to improve the interfacial strength and then to fabricate a high-performance green composite with polylactic acid (PLA) and hemp yarn. Dip coating was carried out for hemp yarn and the green composites were fabricated by hot processing. The coated green composite achieves a high tensile strength of 117 MPa even though the fiber volume fraction is less than 30%. Interfacial shear strength (IFSS) was measured by a single fiber pull-out test, and the effect of water-soluble resin on the tensile properties of the composites was evaluated. As a result, when using coated natural bundles, the IFSS value is smaller than when using noncoated natural bundles. On the basis of observations of the fractured surface of composites and initial yarns using a scanning electron microscope (SEM), the effect of the impregnation of water-soluble resin into the natural bundles on the tensile strength is discussed in detail. It is found that water-soluble resin is effective in improving the mechanical properties of the composite, although the interfacial strength between PLA and water-soluble resin was decreased, and as a result, the tensile strength of green composites increases by almost 20%.

Manabe, Ken-Ichi; Hayakawa, Tomoyuki

339

Ion Exchange Temperature Testing with SRF Resin  

SciTech Connect

Ion exchange using the Spherical Resorcinol-Formaldehyde (SRF) resin has been selected by the U.S. Department of Energy’s Office of River Protection for use in the Pretreatment Facility of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) and for potential application in an at-tank deployment for removing 137Cs. Recent proposed changes to the WTP ion exchange process baseline indicate that higher temperatures (50°C) to alleviate post-filtration precipitation issues prior to reaching the ion exchange columns may be required. Therefore, it is important to understand the behavior of SRF resin performance under the conditions expected with the new equipment and process changes. This research examined the impact of elevated temperature on resin loading and resin degradation during extended solution flow using elevated temperature (45°, 50°, 55°, 60°, 65°, 75°C). Testing for extended times at elevated temperatures showed that the resin does degrade and loading capacity is reduced at and above 45°C. Above 60°C the resin appears to not load at all.

Russell, Renee L.; Rinehart, Donald E.; Brown, Garrett N.; Peterson, Reid A.

2012-03-01

340

[Resin-bonded fixed partial dentures].  

PubMed

A resin-bonded fixed partial denture is a prosthetic construction which can replace I or several teeth in an occlusal system and which comprises a pontic element which is adhesively attached to 1 or more abutment teeth. To compensate for the limited shear strength of the adhesive layer, the Jixed partial denture is occlusally supported by the abutment(s). A direct resin-bonded fixed partial denture is made of composite, reinforced or not by a frame of flexible metal or fiber material. For an indirect resin-bonded fixed partial denture, a metal, fibre-reinforced composite or ceramic substructure is fabricated in a dental laboratory. The basic principle of a resin-bonded fixed partial denture is minimal invasiveness. However, a restoration in an abutment tooth requires a certain occlusal space which is realized by tooth preparation. Resistance preparations may be performed to improve the longevity of resin-bonded fixed partial dentures. Both financially and biologically, a resin-bonded bridge is a cost-effective prosthetic construction. The longevity is limited, but when the construction fails the negative consequences for the abutments are generally limited, which leaves open several types of other treatments. PMID:23495569

Kreulen, C M; Creugers, N H J

2013-02-01

341

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

342

Three new pentasaccharide resin glycosides from the roots of sweet potato (Ipomoea batatas).  

PubMed

Three new pentasaccharide resin glycosides, batatosides III-V (1-3), were isolated from the roots of Sweet potato (Ipomoea batatas). Saponification of the crude resin glycoside mixture yielded substituents and simonic acid B. The structures of the isolated compounds (1-3) were established through spectroscopic analyses, including high field NMR spectroscopy and HR-ESI-MS, and chemical correlation. The major characteristics of 3 are the presence of three different substituents, especially the substituent of cinnamic acid was seldom. The monosaccharides of 1-3 were proved by GC-MS and the absolute configuration of aglycone was further established as S by Mosher's method with R-methyloxyphenylacetic acid (MPA) and S-MPA. PMID:19043237

Yin, Yong-Qin; Huang, Xue-Feng; Kong, Ling-Yi; Niwa, Masatake

2008-12-01

343

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

344

Epoxy resin system for in situ rehabilitation of pipes  

SciTech Connect

This patent describes a process for in situ pipe rehabilitation. It comprises: impregnating a fibrous substrate with a liquid epoxy resin composition comprising at least one liquid epoxy resin having epoxide equivalent weight within the range of about 165 to about 195; a minor amount, relative to the liquid epoxy resin, of an epoxide functional reactive diluent; a minor amount, relative to the liquid epoxy resin, of a thixotroping agent; and an effective amount of a liquid curing agent comprising a polyamide resin, a polyoxalkylenediamine, and from about 35 to about 55 weight percent, based on the weight of component, of 2-ethyl-4-methyl imidazole or derivatives thereof; positioning the resin-impregnated fibrous substrate within a pipe to be rehabilitated so that a surface of the resin-impregnated fibrous substrate is in contact with the interior surface of the pipe; and subjecting the thus-positioned resin-impregnated fibrous substrate to conditions effective to cure the liquid epoxy resin.

Edwards, G.D.; Wilson, B.S.

1992-04-14

345

Switch to an advanced ion exchange resin cuts boiler costs  

SciTech Connect

This article discusses how a field study demonstrated how that one refinery could save $384,000/yr by changing boiler feedwater ion exchange resin. Constant deterioration of ion exchange resin, used to demineralize boiler feedwater, prompted Star Enterprise to conduct a side-by-side evaluation of two resins. The study compared the macroporous weak base anion (WBA) resin that the refinery had used for years with a new WBA resin that features a uniform particle size. The results of this field trial, which was conducted over an 18-month period, showed that the uniform particle size resin had a higher resistance to organic fouling and produced an average of 28 percent more treated water per cycle than the old resin. Replacement and regeneration costs with the new resin resulted in a $48,000 annual savings per bed of resin.

Kratzer, W.R.; Coker, S.D.

1994-10-01

346

Magnetic ion-exchange resin treatment: Impact of water type and resin use  

Microsoft Academic Search

Three raw waters of fundamentally different natural organic matter (NOM) character were treated by magnetic resin using a bench-scale method designed to mimic how the resin is used in continuous operation. Increasing water hydrophobicity resulted in reduced dissolved organic carbon (DOC) removal with removal of 56%, 33% and 25% for waters containing 21%, 50% and 75% hydrophobic NOM, respectively. Study

Max R. D. Mergen; Bruce Jefferson; Simon A. Parsons; Peter Jarvis

2008-01-01

347

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

Microsoft Academic Search

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

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

2007-01-01

348

Effect of resin hydrophilicity and temperature on water sorption of dental adhesive resins  

Microsoft Academic Search

This study examined the effects of copolymer hydrophilicity and temperature on water sorption and solubility characteristics of five copolymer blends of increasing degree of hydrophilicity using gravimetric measurements. Six resin disks (15mm in diameter×1mm in thickness) were prepared from each copolymer blend and were stored in deionised water at 23, 37 and 55°C. Water sorption and solubility of the resin

Cynthia K. Y. Yiu; Nigel M. King; Marcela R. O. Carrilho; Salvatore Sauro; Frederick A. Rueggeberg; Carlo Prati; Ricardo M. Carvalho; David H. Pashley; Franklin R. Tay

2006-01-01

349

Emulsion Paint of Aromatic Petroleum Resin. I. Emulsification of Aromatic Petroleum Resin Solution in Water  

Microsoft Academic Search

Industrial emulsification of an aromatic petroleum resin solu tion in bodied linseed oil was investigated using an emulsion inversion process. It was found that the preferred surfactant had the best match in solubility parameter between olefinic group and resin solution A slight variation was found in optimum H LB for emulsification, depending on the chemical family of surfactants chosen, but

Yoshiyuki Iwase

1980-01-01

350

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

351

The Case for Polylactic Acid as a Commodity Packaging Plastic  

Microsoft Academic Search

Polylactide, sometimes called polylactic acid (PLA), meets many requirements as a packaging thermoplastic and is suggested as a commodity resin for general packaging applications. Its general physical properties and melt processing ease are similar to conventional packaging resins. PLA slowly degrades by hydrolysis in even a slightly moist environment over a period of several months to a year to environmentally-friendly

R. G. Sinclair

1996-01-01

352

Thermal cycling effects on adhesion of resin-bovine enamel junction among different composite resins.  

PubMed

Thermal cycling is used to mimic the changes in oral cavity temperature experienced by composite resins when used clinically. The purpose of this study is to assess the thermal cycling effects of in-house produced composite resin on bonding strength. The dicalcium phosphate anhydrous filler surfaces are modified using nanocrystals and silanization (w/NP/Si). The resin is compared with commercially available composite resins Filtek Z250, Z350, and glass ionomer restorative material GIC Fuji-II LC (control). Different composite resins were filled into the dental enamel of bovine teeth. The bond force and resin-enamel junction graphical structures of the samples were determined after thermal cycling between 5 and 55°C in deionized water for 600 cycles. After thermal cycling, the w/NP/Si 30wt%, 50wt% and Filtek Z250, Z350 groups showed higher shear forces than glass ionomer GIC, and w/NP/Si 50wt% had the highest shear force. Through SEM observations, more of the fillings with w/NP/Si 30wt% and w/NP/Si 50wt% groups flowed into the enamel tubule, forming closed tubules with the composite resins. The push-out force is proportional to the resin flow depth and uniformity. The push-out tubule pore and resin shear pattern is the most uniform and consistent in the w/NP/Si 50wt% group. Accordingly, this developed composite resin maintains great mechanical properties after thermal cycling. Thus, it has the potential to be used in a clinical setting when restoring non-carious cervical lesions. PMID:25047352

Chen, Wen-Cheng; Ko, Chia-Ling; Wu, Hui-Yu; Lai, Pei-Ling; Shih, Chi-Jen

2014-10-01

353

New bismaleimide matrix resins for graphite fiber composites  

NASA Technical Reports Server (NTRS)

Two new bismaleimide resins based on the N,N'-m-phenylene-bis(m-amino-benzamide) structure have been synthesized and characterized. The mixtures of the two resins gave better handling, processing, mechanical, and thermal properties in graphite composites than did the individual resins. The mechanical strength of the cured graphite composites prepared from the 1:1 copolymer of the two bismaleimide resins was excellent at both ambient and elevated temperatures. The physical and mechanical properties of the composites from the new bismaleimide matrix resin systems are compared with conventional composites based on epoxy and other bismaleimide systems. The copolymer system provides another method for improving bismaleimide resins.

Hsu, M.-T. S.; Chen, T. S.; Parker, J. A.; Heimbuch, A. H.

1985-01-01

354

Thermal rearrangement of novolak resins used in microlithography  

NASA Astrophysics Data System (ADS)

Changes in phenolic-formaldehyde resin properties are described in terms of thermal exposure. At high temperature, resin molecular weight, dissolution properties and chemical composition change depending on the presence or absence of monomers. Without monomer in the resin melt at 220 degree(s)C, resin molecular weight increases with a corresponding decrease in dissolution rate. In the presence of monomer, molecular weight generally decreases. Dissolution rate may fluctuate depending on the monomer mixture. Three,five- Xylenol and 2,3,5-trimethylphenol co-monomers induced the most extreme changes in resin properties with thermal treatment. Resin degradation-recombination processes suggest a classical Friedel-Craft rearrangement mechanism.

Hardy, Ricky; Zampini, Anthony; Monaghan, Michael J.; O'Leary, Michael J.; Cardin, William J.; Eugster, Timothy J.

1995-06-01

355

Influence of Nd:YAG or Er:YAG laser surface treatment on microtensile bond strength of indirect resin composites to resin cement. Lasers surface treatment of indirect resin composites.  

PubMed

This study evaluated the influence of the surface pretreatment of indirect resin composite (Signum, Admira Lab and Sinfony) on the microtensile bond strength of a resin cement. Sixty samples made of each brand were divided into 6 groups, according to surface treatment: (1) control; (2) controlled-air abrasion with Al2O3; (3) Er:YAG Laser 200 mJ, 10 Hz, for 10s; (4) Er: YAG Laser 300 mJ, 10 Hz, for 10 s; (5) Nd:YAG 80 mJ, S15Hz for 1 min; (6) Nd:YAG 120mJ, 15 Hz for 1 min. After treatments, all the groups received an application of 37% phosphoric acid and adhesive. The pair of blocks of the same brand were cemented to each other with dual resin cement. The blocks were sectioned to obtain resin-resin sticks (1 x1 mm) and analyzed by microtensile bond testing. The bond strength values were statistically different, irrespective of the surface treatment performed, with highest values for Sinfony (43.81 MPa) and lowest values for Signum (32.33 MPA). The groups treated with the Nd:YAG laser showed the lowest bond strength values and power did not interfere in the results, both for Nd:YAG laser and Er:YAG. Controlled-air abrasion with Al203 is an efficient surface treatment method and the use of the Nd:YAG and Er:YAG lasers reduced bond strength, irrespective of the intensity of energy used. PMID:23101180

Caneppele, T M F; de Souza, A C Oliveira; Batista, G R; Borges, A B; Torres, C R G

2012-09-01

356

Colesevelam and colestipol: novel medication resins in the gastrointestinal tract.  

PubMed

We report the morphologic description of the bile acid sequestrants (BAS) colesevelam and colestipol, as well as the largest series of cholestyramine. Histologically similar medication resins from 4 institutions were prospectively collected over 1 year (26 specimens, 15 patients). Comorbidities included hyperlipidemia (4/15), hypertension (4/15), inflammatory bowel disease (4/15), coronary artery disease (3/15), diarrhea (7/15), hypothyroidism (2/15), and ischemic bowel (1/15). Sites of involvement included the esophagus (1/26), stomach (1/26), small intestine (1/26), ileocecal valve (1/26), and colorectum (22/26). Associated histologic diagnoses included normal (8/26), chronic mucosal injury (11/26), acute inflammation (9/26), erosion/ulceration (6/26), and cytomegalovirus (2/26). The BAS resins were histologically indistinguishable from each other; they were all eosinophilic on hematoxylin and eosin (H&E) and lacked internal "fish-scales." To validate these observations, respective medications were submitted for histologic processing; the processed medications were identical to those in the patient specimens. Rare, irregular "fracture" lines presented diagnostic pitfalls by mimicking the true "fish-scales" of Kayexalate and sevelamer. Clues to the correct identification of BAS include recognition that the "fracture" lines were subtle, irregular, and restricted to large fragments or thick sections, likely representing a processing artifact. Moreover, Kayexalate is violet on H&E and black on acid fast bacillus, and sevelamer characteristically displays a 2-tone color on H&E and is magenta on acid fast bacillus. An association with inflammatory injury was seen (15/26). We believe that the BAS are innocent bystanders in complicated patients, although we cannot exclude their ability to cause mucosal injury in specific settings. PMID:24921636

Arnold, Michael A; Swanson, Benjamin J; Crowder, Clinton D; Frankel, Wendy L; Lam-Himlin, Dora; Singhi, Aatur D; Stanich, Peter P; Arnold, Christina A

2014-11-01

357

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

358

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

359

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

360

Improved high temperature resistant matrix resins  

NASA Technical Reports Server (NTRS)

The objective was to develop organic matrix resins suitable for service at temperatures up to 644 K (700 F) and at air pressures up to 0.4 MPa (60 psia) for time durations of a minimum of 100 hours. Matrix resins capable of withstanding these extreme oxidative environmental conditions would lead to increased use of polymer matrix composites in aircraft engines and provide significant weight and cost savings. Six linear condensation, aromatic/heterocyclic polymers containing fluorinated and/or diphenyl linkages were synthesized. The thermo-oxidative stability of the resins was determined at 644 K and compressed air pressures up to 0.4 MPa. Two formulations, both containing perfluoroisopropylidene linkages in the polymer backbone structure, exhibited potential for 644 K service to meet the program objectives. Two other formulations could not be fabricated into compression molded zero defect specimens.

Chang, G. E.; Powell, S. H.; Jones, R. J.

1983-01-01

361

[Allergic contact eczema from epoxy resin].  

PubMed

Epoxy resins are plastics that are widely used as electrical insulation, in coatings, and as adhesives and paints. They have strong sensitizing power and are one of the main causes of allergic contact eczema, both in the workplace and elsewhere. We present the case of a worker at a plastics/chemical plant, who handled aeronautical components in the process of manufacturing fuselage parts. He consulted his physician because of eczematous lesions on his fingers, hands and forearms which had developed over a two-year period and were clearly related to his work. The standard battery of skin tests was performed, along with the plastics and adhesives series and tests using the products from his workplace. Positivity was shown to epoxy resins (standard battery) and to the products from his workplace, which included different fiberglass and carbon fiber sheets impregnated with epoxy resins and epoxy adhesives. PMID:16476309

Calzado, Leticia; Ortiz-de Frutos, Francisco J; del Prado Sánchez-Caminero, María; Galera, Carmen María; Valverde, Ricardo; Vanaclocha, Francisco

2005-11-01

362

Jetted mixtures of particle suspensions and resins  

NASA Astrophysics Data System (ADS)

Drop-on-demand (DoD) ink-jetting of hard particle suspensions with volume fraction ? ˜ 0.25 has been surveyed using 1000 ultra-high speed videos as a function of particle size (d90 = 0.8—3.6 ?m), with added 2 wt. % acrylic (250 kDa) or 0.5 wt. % cellulose (370 kDa) resin, and also compared with Newtonian analogues. Jet break-off times from 80 ?m diameter nozzles were insensitive (120 ± 10 ?s) to particle size, and resin jet break-off times were not significantly altered by >30 wt. % added particles. Different particle size grades can be jetted equally well in practice, while resin content effectively controls DoD break-off times.

Hoath, S. D.; Hsiao, W.-K.; Hutchings, I. M.; Tuladhar, T. R.

2014-10-01

363

Setting Reaction of Polyacid Modified Composite Resins or Compomers  

PubMed Central

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

364

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

365

Biphenyl liquid crystalline epoxy resin as a low-shrinkage resin-based dental restorative nanocomposite.  

PubMed

Low-shrinkage resin-based photocurable liquid crystalline epoxy nanocomposite has been investigated with regard to its application as a dental restoration material. The nanocomposite consists of an organic matrix and an inorganic reinforcing filler. The organic matrix is made of liquid crystalline biphenyl epoxy resin (BP), an epoxy resin consisting of cyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECH), the photoinitiator 4-octylphenyl phenyliodonium hexafluoroantimonate and the photosensitizer champhorquinone. The inorganic filler is silica nanoparticles (?70-100 nm). The nanoparticles were modified by an epoxy silane of ?-glycidoxypropyltrimethoxysilane to be compatible with the organic matrix and to chemically bond with the organic matrix after photo curing. By incorporating the BP liquid crystalline (LC) epoxy resin into conventional ECH epoxy resin, the nanocomposite has improved hardness, flexural modulus, water absorption and coefficient of thermal expansion. Although the incorporation of silica filler may dilute the reinforcing effect of crystalline BP, a high silica filler content (?42 vol.%) was found to increase the physical and chemical properties of the nanocomposite due to the formation of unique microstructures. The microstructure of nanoparticle embedded layers was observed in the nanocomposite using scanning and transmission electron microscopy. This unique microstructure indicates that the crystalline BP and nanoparticles support each other and result in outstanding mechanical properties. The crystalline BP in the LC epoxy resin-based nanocomposite was partially melted during exothermic photopolymerization, and the resin expanded via an order-to-disorder transition. Thus, the post-gelation shrinkage of the LC epoxy resin-based nanocomposite is greatly reduced, ?50.6% less than in commercialized methacrylate resin-based composites. This LC epoxy nanocomposite demonstrates good physical and chemical properties and good biocompatibility, comparable to commercialized composites. The results indicate that this novel LC nanocomposite is worthy of development and has potential for further applications in clinical dentistry. PMID:22842038

Hsu, Sheng-Hao; Chen, Rung-Shu; Chang, Yuan-Ling; Chen, Min-Huey; Cheng, Kuo-Chung; Su, Wei-Fang

2012-11-01

366

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

367

Resin additive improves performance of high-temperature hydrocarbon lubricants  

NASA Technical Reports Server (NTRS)

Paraffinic resins, in high temperature applications, improve strength of thin lubricant film in Hertzian contacts even though they do not increase bulk oil viscosity. Use of resin circumvents corrosivity and high volatility problems inherent with many chemical additives.

Johnson, R. L.; Loomis, W. R.

1971-01-01

368

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 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....

2011-04-01

369

Influence of resin coating materials on Porphyromonas gingivalis attachment.  

PubMed

Resin coating materials have been used for composite resin or provisional restoration in order to prevent plaque accumulation on their surfaces. However, it is not clear whether the coating materials influence attachment of periodontal bacteria. Therefore, we investigated the effect of resin coating materials on the attachment of Porphyromonas gingivalis (Pg). The polymerized auto cure resin plates were coated with two resin coating materials. To estimate the Pg attachment, each plate was immersed in brain heart infusion medium containing Pg. The quantity of bacteria attached on each plate was evaluated by crystal violet quantification. Morphological change of Pg was recorded using scanning electron microscopy. Both coating groups presented significantly lower Pg attachment compared to the control. The Pg shapes on the plates with resin coating materials were similar to the non-treated control plates. The resin coating materials clearly prevent Pg attachment on the polymerized auto cure resin plate. PMID:22277610

Kumada, Ai; Matsuka, Yoshizo; Mine, Atsushi; Ono, Mitsuaki; Uehara, Junji; Sonoi, Norihiro; Ito, Takashi; Takashiba, Shogo; Kuboki, Takuo

2012-02-01

370

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

371

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

372

Use of crystalline, crosslinked synthetic resins as a storage material in latent heat stores  

SciTech Connect

The invention relates to the use of crystalline resins as storage material in latent heat accumulators. Crystalline synthetic resins replace the crystalline inorganic salt of the known latent heat reservoirs. Preferably epoxide resins, polyurethane resins and polyester resins, which contain very specific long-chain polyester molecule moieties, are used. The crystalline synthetic resins have one or more, preferably two, crystallite melt temperatures.

Kreibich, U.; Schmid, R.

1981-03-31

373

Effects of etching and adhesive applications on the bond strength between composite resin and glass-ionomer cements  

PubMed Central

Objective This study determined the effects of various surface treatment modalities on the bond strength of composite resins to glass-ionomer cements. Material and Methods Conventional (KetacTM Molar Quick ApplicapTM) or resin-modified (PhotacTM Fil Quick AplicapTM) glass-ionomer cements were prepared. Two-step etch-rinse & bond adhesive (AdperTM Single Bond 2) or single-step self-etching adhesive (AdperTM PromptTM L-PopTM) was applied to the set cements. In the etch-rinse & bond group, the sample surfaces were pre-treated as follows: (1) no etching, (2) 15 s of etching with 35% phosphoric acid, (3) 30 s of etching, and (4) 60 s of etching. Following the placement of the composite resin (FiltekTM Z250), the bond strength was measured in a universal testing machine and the data obtained were analyzed with the two-way analysis of variance (ANOVA) followed by the Tukey's HSD post hoc analysis (p=0.05). Then, the fractured surfaces were examined by scanning electron microscopy. Results The bond strength of the composite resin to the conventional glass-ionomer cement was significantly lower than that to the resin-modified glass-ionomer cement (p<0.001). No significant differences were determined between the self-etching and etch-rinse & bond adhesives at any etching time (p>0.05). However, a greater bond strength was obtained with 30 s of phosphoric acid application. Conclusions The resin-modified glass-ionomer cement improved the bond strength of the composite resin to the glass-ionomer cement. Both etch-rinse & bond and self-etching adhesives may be used effectively in the lamination of glass-ionomer cements. However, an etching time of at least 30 s appears to be optimal. PMID:23329245

PAMIR, Tijen; SEN, Bilge Hakan; EVCIN, Ozgur

2012-01-01

374

The nature and origin of sesquiterpenoids in some tertiary fossil resins  

NASA Astrophysics Data System (ADS)

Analyses of two Tertiary fossil resins and a Tertiary montan wax have revealed the presence of a number of sesquiterpenoids. Using gas chromatographic retention data obtained on both polar and non-polar stationary phases and mass spectral comparisons with authentic compounds, the sesquiterpenoids ?-cedrene, cedrane, cuparene, cedren-10-one, 8?H cedran-9-one and cuparenic acid have been identified in the fossil resin retinellite and a montain wax (both Oligocene) from lignite beds in the Bovey basin of Devon, England, and in the Pliocene fossil resin ionite from the lone valley of California. U.S.A. The sesquiterpenoids ?-cedrene, cuparene and cuparenic acid are characteristic constituents of the essential oils of the Cupressaceae, a family of trees and shrubs of the order Coniferales, and it is argued that these fossil resins, and the montan wax, were derived from older forms of this family of plants. The ketones cedren-10-one and 8?H cedran-9-one, and the saturated hydrocarbon cedrane, are not reported to be constituents of modern genera of Cupressaceae and may have been formed during diagenesis. The cedrane occurring in these deposits appears to be a chemical hydrogenation product of ?-cedrene. The ketones, on the other hand, may have resulted from the oxidation of ?-cedrene although the mechanism of these reactions is not clear. If the ketones are not undetected constituents of these plants, then the presence in these deposits of both oxidised and fully-reduced ?-cedrene products infers that separate phases of oxidation and reduction occurred during the diagenesis of the fossil resins and the montan wax.

Grantham, P. J.; Douglas, A. G.

1980-11-01

375

From waste to functional additive: toughening epoxy resin with lignin.  

PubMed

A novel approach to toughen epoxy resin with lignin, a common waste material from the pulp and paper industry, is presented in this article. First, carboxylic acid-functionalized alkali lignin (AL-COOH) was prepared and subsequently incorporated into anhydride-cured epoxy networks via a one-pot method. The results of mechanical tests show that covalent incorporation of rigid AL-COOH into epoxy networks can significantly toughen the epoxy matrix without deteriorating its tensile strength and modulus. The addition of 1.0 wt % AL-COOH gives increases of 68 and 164% in the critical stress intensity factor (K(IC)) and critical strain energy release rate (G(IC)), respectively, relative to that of neat epoxy. This article opens up the possibility of utilizing low-cost and renewable lignin feedstocks as effective toughening agents for thermoset polymers. PMID:24660855

Liu, Wanshuang; Zhou, Rui; Goh, Hwee Li Sally; Huang, Shu; Lu, Xuehong

2014-04-23

376

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

...Use Only as Components of Paper and Paperboard § 176...adjuvants in the manufacture of paper and paperboard in amounts...necessary to accomplish the technical effect and not to exceed 2 percent by weight of the paper or...

2014-04-01

377

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2012 CFR

...Use Only as Components of Paper and Paperboard § 176...adjuvants in the manufacture of paper and paperboard in amounts...necessary to accomplish the technical effect and not to exceed 2 percent by weight of the paper or...

2012-04-01

378

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2013 CFR

...Use Only as Components of Paper and Paperboard § 176...adjuvants in the manufacture of paper and paperboard in amounts...necessary to accomplish the technical effect and not to exceed 2 percent by weight of the paper or...

2013-04-01

379

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2011 CFR

...Use Only as Components of Paper and Paperboard § 176...adjuvants in the manufacture of paper and paperboard in amounts...necessary to accomplish the technical effect and not to exceed 2 percent by weight of the paper or...

2011-04-01

380

21 CFR 573.120 - Acrylamide-acrylic acid resin.  

Code of Federal Regulations, 2011 CFR

...units. (b) The additive meets the following specifications: (1) A minimum molecular weight of 3 million. (2) Viscosity range: 3,000 to 6,000 centipoises at 77 °F in a 1 percent aqueous solution as determined by LVF Brookfield...

2011-04-01

381

Storage effect of a pre-activated silane on the resin to ceramic bond  

Microsoft Academic Search

Objectives. The purpose of this study was to investigate the process of hydrolysis and chemical stability of a pre-activated silane solution stored for different periods of time. The tensile bond strength of resin composite to ceramic was also evaluated in order to determine the functional effectiveness after storage of the pre-activated silane solutions.Methods. Silane solutions using ?-methacryloxypropyltrimethoxysilane (?-MPTS), acetic acid

Tabassom Hooshmand; Richard van Noort; Alireza Keshvad

2004-01-01

382

Separation of the lanthanides on high-efficiency bonded phases and conventional ion-exchange resins  

Microsoft Academic Search

High-performance liquid chromatographic separations (< 20 min) of the lanthanides are illustrated for both 5- and 10-..mu..m bonded-phase strong-acid ion exchangers. The performance of these bonded phase packings is compared with that obtained with a 13-..mu..m styrene-divinylbenzene resin. The eluted metal ions are detected with a variable-wavelength detector after a post-column complexation reaction. The requirements and characteristics of post-column reaction

S. Elchuk; R. M. Cassidy

1979-01-01

383

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

384

Water-borne and air-drying oil-based resins  

Microsoft Academic Search

New water-borne polyurethane resins were produced using maleinized monoglyceride (MMG), hydroxyl-terminated polybutadiene (HTPB), toluene di-isocyanate, and ethylene diamine (EDA). Maleinization was performed in order to insert hydrophilic groups in the fatty acid residues, which were then inserted to the backbone of polyurethane. The MMG was mixed with HTPB in different proportions, and the mixture was used as the polyol part

G. Gündüz; A. H. Khalid; ?. A. Mecido?lu; L. Aras

2004-01-01

385

Properties of polymeric compositions based on epoxy and functional petroleum polymeric resins  

Microsoft Academic Search

We studied cross-linking, water resistance, and impedance characteristics of polymeric compositions based on epoxydiane and\\u000a maleinized petroleum polymeric resins. It is shown that epoxy and petroleum polymeric components interact at temperatures\\u000a of 150C and higher to form cross-linked copolymers. The gel-fraction content of the composition increases with the acid number\\u000a of the petroleum polymeric component. Small amounts of tertiary amine

V. I. Pokhmurs'kyi; T. V. Humenets'kyi; L. M. Bilyi; Yu. V. Dums'kyi

1996-01-01

386

Properties of epoxy-amine coatings modified with petroleum polymeric resins  

Microsoft Academic Search

We study the composition of the gel fraction, water absorption, and impedance characteristics of epoxy coatings modified with\\u000a petroleum polymeric resin treated with maleic anhydride. It is shown that modified epoxy coatings are characterized by higher\\u000a water resistance and better protective properties in acid media. We determine the optimal amount of the petroleum polymeric\\u000a modifier and demonstrate the possibility of

V. I. Pokhmurs'kyi; T. V. Humenets'kyi; L. M. Bilyi

1996-01-01

387

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

388

Tensile Properties of Resin-infiltrated Demineralized Human Dentin  

Microsoft Academic Search

The ability of adhesive resins to restore the physical properties of demineralized dentin has not been well-documented. The unfilled resins that are used for adhesion have relatively low moduli of elasticity and limited ability to increase dentin stiffness, although they may increase the ultimate tensile strength of dentin. This study tested the hypothesis that resin infiltration of demineralized dentin can

H. Sano; T. Takatsu; B. Ciucchi; C. M. Russell; D. H. Pashley

1995-01-01

389

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2010-07-01

390

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2011-07-01

391

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2013-07-01

392

40 CFR 721.9499 - Modified silicone resin.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Modified silicone resin. 721.9499 Section...Substances § 721.9499 Modified silicone resin. (a) Chemical...identified generically as a modified silicone resin (PMN P-96-1649...uses are: (i) Release to water. Requirements as...

2012-07-01

393

Creep behavior of epoxy resin during irradiation at cryogenic temperature  

Microsoft Academic Search

Creep tests of an epoxy resin during bending and irradiation have been carried out to investigate the synergistic effects of radiation and stress on mechanical properties of the resin. Simultaneous application of stress and irradiation on the epoxy resin enhanced creep rates in comparison with the application of stress on an irradiated sample. In order to clarify the mechanism of

Tetsuya Nishiura; Shigehiro Nishijima; Toichi Okada

1999-01-01

394

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

395

Composites from Natural Fibers and Soy Oil Resins  

Microsoft Academic Search

The goal of this project is to develop new composites using fibers and resins from renewable resources. The ACRES (Affordable Composites from Renewable Sources) group at the University of Delaware has developed new chemistries to synthesize rigid polymers from plant oils. The resins produced contain at least 50% plant triglycerides and have mechanical properties comparable to commercially available synthetic resins

George I. Williams; Richard P. Wool

2000-01-01

396

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2013-04-01

397

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

...2014-04-01 2014-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2014-04-01

398

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2011-04-01

399

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

2012-04-01

400

Occupational asthma due to unheated polyvinylchloride resin dust.  

PubMed

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

1989-11-01

401

Simulation of the C5 Aliphatic Petroleum Resins Production Process  

Microsoft Academic Search

Petroleum resins are used widely in many industries. They are solvable in most of aromatic and aliphatic solvents. There are different grades of petroleum resins from dark and viscose liquids to bright and hard ones. They are used mostly in the adherent industry as binder. In this article the production process of aliphatic petroleum resin is simulated based on the

B. Berahman; B. Dabir; S. Sadeghpour

2010-01-01

402

PETROLEUM RESINS: SEPARATION, CHARACTER, AND ROLE IN PETROLEUM  

Microsoft Academic Search

In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes are precipitated, adsorbents are added to the n-pentane solutions of the resins and oils, by which process the

Simon I. Andersen; James G. Speight

2001-01-01

403

Determination of trace elements in urine using inductively coupled plasma spectroscopy with a poly (dithiocarbamate) chelating resin  

NASA Astrophysics Data System (ADS)

The application or a poly(dithiocarbamate) resin for the concentration and separation of Be, Zn. Mn, Hg, Cu, Co, Tl, Mo, Fe, Ti, and V in urine is developed with inductively coupled plasma-atomic emission spectroscopy. Except for V, the metals studied are quantitatively recovered either directly from urine or from acid-digested urine.

Barnes, Ramon M.; Fodor, Peter; Inagaki, Kenji; Fodor, Marta

404

Anomalous effects in the character of the carbonyl absorption (ca. 1700 cm⁻¹) in the infrared spectra of petroleum resins and asphaltenes  

Microsoft Academic Search

The presence of the carbonyl functional groups in asphaltenes and resins were detected by ir spectroscopy following saponification. By following the spectra through a reaction sequence, the bituminous extracts from fresh oil sands showed the presence of esters and carboxylic acids. The extracts from a hot water process showed either carboxylic acids or esters. 1 figure, 2 tables.

J. G. Speight; S. E. Moschopedis

1981-01-01

405

Resin Powder Slurry Process for Composite Fabrication  

NASA Technical Reports Server (NTRS)

Potentially useful process for fabrication of fiber-reinforced resinmatrix composites is powder slurry technique. Applicability of technique demonstrated using powdered resin made from thermoplastic polyimide LaRC/ TPI (thermoplastic polyimide). Use of process circumvents need for such high-cost organic solvents as N-methylpyrrolidinone and diglyme (diglycol methyl ether). Two basic slurries for LaRC/TPI powder investigated.

Mike, R. A.

1986-01-01

406

Resin Vacuum Casting System for LED Screen  

Microsoft Academic Search

This paper mainly describes the resin vacuum casting system for LED screen which uses thin film degassing technology and meter mix technology. Thin film degassing technology is currently the most effective method. In this paper, we describe in detail its working model. And meter mix dispensing technology integrates metering pump and mixing pump. It mixes materials according to the demand.

Hong Robin; Wang Hongmei; Hu Ming

2010-01-01

407

Ternary Resin-Bound Dynamic Combinatorial Chemistry  

PubMed Central

The ability to carry out simultaneous orthogonal exchange chemistries has opened new opportunities for increasing the numerical and structural diversity accessible to Dynamic Combinatorial Chemistry. We present proof-of-concept experiments demonstrating this concept is transferrable to resin-bound DCC, facilitating the generation and analysis of libraries with greater structural diversity. PMID:22240966

Gromova, Anna V.; Ciszewski, Joseph M.; Miller, Benjamin L.

2013-01-01

408

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

409

Process for manufacturing a petroleum resin  

Microsoft Academic Search

The present invention relates to a process for manufacturing a petroleum resin wherein a fraction (Component a) containing an aromatic hydrocarbon obtained by cracking of petroleum and a thermally polymerized oil (Component b) obtained by previously thermal-polymerizing the component a are mixed and then the mixture of the components a and B is subjected to polymerization by employing a Friedel-Crafts

T. Iwashita; M. Nagano; K. Tanaka

1981-01-01

410

Resin transfer molding speeds composite making  

NASA Astrophysics Data System (ADS)

Fabrication resin transfer molding (RTM) composite parts for different industrial applications is discussed. These applications include composite aerospace parts, sports car components, and high performance sporting equipment. It is pointed out that RTM parts are lighter than metals and can be formulated to have superior durability. But like all composite parts, they are expensive and are made in limited runs.

Valenti, Michael

1992-11-01

411

Effect of posterior resin composite placement technique on the resin-dentin interface formed in vivo  

Microsoft Academic Search

Objective: The aim of this study was to evaluate the morphology of the resin-dentin interface formed in vivo with two posterior resin composite placement techniques (incremental and bulk). Method and materi- als: After approval from the patients, 12 Class II cavities with margins in enamel (2.5 2.5 4.5 mm) were prepared in caries-free premolars scheduled to be extracted for orthodontic

Guilherme Carpena Lopes; Luiz Narciso Baratieri; Sylvio Monteiro; Luiz Clóvis Cardoso Vieira

412

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

413

Cation exchange resin immobilized bimetallic nickel-iron nanoparticles to facilitate their application in pollutants degradation.  

PubMed

Nanoscale zerovalent iron (nZVI) usually suffers from reduction of reactivity by aggregation, difficulty of assembling, environmental release and health concerns. Furthermore, data are lacking on the effect of cheap nickel on debromination of decabromodiphenyl ether (DBDE) by immobilized nZVI in aqueous system. In this study, strong acid polystyrene cation-exchange resins with particle diameter from 0.4 to 0.6 mm were utilized as matrices to immobilize bimetallic nickel-iron nanoparticles in order to minimize aggregation and environmental leakage risks of nZVI and to enhance their reactivity. Elemental distribution mapping showed that iron particles distributed uniformly on the surface of the resin and nickel particles were dispersed homogeneously into Fe phase. The reaction rate of resin-bound nZVI is about 55% higher than that of dispersed nZVI. The immobilized bimetallic nanoparticles with 9.69% Ni had the highest debromination percent (96%) and reaction rate (0.493 1/h). The existence of Ni significantly improved the debromination rate, due to the surface coverage of catalytic metal on the reductive metal and the formation of a galvanic cell. The environmental dominant congeners, such as BDE 154, 153, 100, 99 and 47, were produced during the process. Outstanding reactive performance, along with magnetic separation assured that resin-bound bimetallic nickel-iron nanoparticles are promising material that can be utilized to remediate a wide variety of pollutants contaminated sites including polybrominated diphenyl ethers. PMID:24559714

Ni, Shou-Qing; Yang, Ning

2014-04-15

414

Catalytic wet peroxide oxidation of p-nitrophenol by Fe (III) supported on resin.  

PubMed

Fe(III) supported on resin (Fe(III)-resin) as an effective catalyst for peroxide oxidation was prepared and applied for the degradation of p-nitrophenol (PNP). Catalytic wet peroxide oxidation (CWPO) experiments with hydrogen peroxide as oxidant were performed in a batch rector with p-nitrophenol as the model pollutant. Under given conditions (PNP concentration 500?mg/L, H(2)O(2) 0.1?M, 80°C, resin dosage 0.6% g/mL), p-nitrophenol was almost completely removed, corresponding to an 84% of COD removal. It was found that the reaction temperature, oxidant concentration. and initial pH of solution significantly affected both p-nitrophenol conversion and COD removal by oxidation. It can be inferred from the experiments that Fe(III) supported on resin was an effective catalyst in the mineralization of p-nitrophenol. In an acidic environment of oxidation, the leaching test showed that there was only a slight leaching effect on the activity of catalytic oxidation. It was also confirmed by the aging test of catalysts in the oxidation. PMID:20962404

Liou, Rey-May; Chen, Shih-Hsiung; Huang, Cheng-Hsien; Lai, Cheng-Lee; Shih, C Y; Chang, Jing-Song; Hung, Mu-Ya

2010-01-01

415

Resin film infusion mold tooling and molding method  

NASA Technical Reports Server (NTRS)

A mold apparatus and method for resin film infusion molding including an outer mold tool having a facing sheet adapted to support a resin film and preform assembly. The facing sheet includes attachment features extending therefrom. An inner mold tool is positioned on the facing sheet to enclose the resin film and preform assembly for resin film infusion molding. The inner mold tool includes a plurality of mandrels positioned for engagement with the resin film and preform assembly. Each mandrel includes a slot formed therein. A plurality of locating bars cooperate with the slots and with the attachment features for locating the mandrels longitudinally on the outer mold tool.

Burgess, Roger (Inventor); Grossheim, Brian (Inventor); Mouradian, Karbis (Inventor); Thrash, Patrick J. (Inventor)

1999-01-01

416

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 in the fully wet condition. Chloride concentration in the first batch (No.80302MA) was nearly the same before the current treatment (759 ppm dry) and after treatment (745 ppm dry or {approx}248 ppm wet). Treatment of the second batch of resin (No.23408) was very successful. Chloride concentration decreased from 120,000 ppm dry to an average of 44 ppm dry or {approx}15ppm wet, which easily passes the 250 ppm wet criterion. Per guidance from HB Line Engineering, SRNL blended Batch 80302 resin with Batch P9059 resin which had been treated previously by ResinTech to remove chloride. The chloride concentrations for the two drums of Batch P9059 were 248 ppm dry ({approx}83 ppm wet) {+-}22.8% and 583 ppm dry ({approx}194 ppm wet) {+-} 11.8%. The blended resin was packaged in five gallon buckets.

Steimke, J.; Williams, M.; Steeper, T.; Leishear, R.

2012-05-29

417

Removal of phenol from saline water by polyamine chelating resin.  

PubMed

Removal of phenol from saline water was carried out with chelating resin. A polyamine chelating resin, Diaion CR-20, removed phenol compounds selectively from industrial wastewater containing 2% salt. From saline water containing 20 mg/L phenol, 70% of the phenol was removed. After treatment, phenol was eluted from the resin by aqueous NaOH, and the resin could also be regenerated by heating in air. Diaion CR-20 adsorbed phenol even in the presence of FeCl3, indicating that treatment with this resin of wastewater containing metal can remove phenol and metal cations in a single step. PMID:24185065

Yamada, Arisa; Matsui, Akihiro; Tsuji, Hideyuki

2013-01-01

418

Method for detecting resin leakage in LWR coolant  

SciTech Connect

Resin leakage from condensate polishing units can result in steam generator corrosion. This report describes the development of a resin leakage detection method based in analyzing the organic breakdown products released from resin on heating. The breakdown products are analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. Some of the organic products formed have been identified. A design for a resin monitoring unit, suitable for incorporation into the IONTRAC system, is presented. Theoretically, detection of ppB levels of resin by processing about one liter of water, is possible.

Girard, J.E.

1988-05-01

419

Programmed gelation of polymers using melamine resins  

SciTech Connect

This patent describes a process for enhancing the amount of oil recovered from a subterranean oil-bearing formation having relatively high permeability zones and relatively low permeability zones penetrated by at least one injection well and at least one production well by selectively plugging at least a portion of the relatively high permeability zones with a profile control gel. It comprises: determining a quantity of a gel-forming mixture required for the selective plugging of at least a portion of the relatively high permeability zones within the formation and the period of time within which full gelation of the mixture is to be completed; preparing a gel-forming mixture comprising a polymer which is crosslinkable by reaction with an amino resin, a rapid amino resin crosslinking agent and a delayed amino resin crosslinking agent, the gel-forming mixture capable of complete gelation within the period of time determined; partially gelling the mixture to impart selectivity to the mixture by reacting the polymer with the rapid amino resin crosslinking agent which is effective to complete the partial gelation by crosslinking the polymer to form a viscous liquid; injecting the viscous liquid into the relatively high permeability zones within the formation; fully gelling the viscous liquid by reacting the polymer with the delayed amino resin crosslinking agent which is effective to complete the full gelation by crosslinking the polymer within the period of time determined; injecting a flooding fluid into the relatively low permeability zones of the formation via the injection well; and recovering fluids including oil from the formation via the production well.

Shu, P.

1990-10-23

420

Speciation of Cr(III) and Cr(VI) in environmental samples by solid phase extraction on Ambersorb 563 resin.  

PubMed

A simple and sensitive method for the speciation, separation and preconcentration of Cr(VI) and Cr(III) in natural water, soil and sediment samples was developed. Cr(VI) has been separated from Cr(III) and preconcentrated as Cr(III)-diphenylcarbazone complex by using Ambersorb 563 resin and determined by spectrophotometric method at 540 nm. Effect of analytical parameters such as sulfuric acid concentration, ligand volume, type of elution solution, sample volume, amount of resin and foreign ions were investigated. The presented procedure was successfully applied for the chromium speciation in various environmental samples with successfully results. PMID:16442725

Narin, Ibrahim; Surme, Yavuz; Soylak, Mustafa; Dogan, Mehmet

2006-08-25

421

Recovery of palladium(II) and gold(III) from diluted liquors using the resin duolite GT73  

Microsoft Academic Search

The adsorption of Pd(II) and Au(III) on the Duolite GT-73 has been investigated. The results obtained in chloride media showed a higher adsorption for Au(III) (0.58±0.03mmol\\/g resin) than for Pd(II) (0.262±0.015mmol\\/g resin); however, the adsorption for Pd(II) is faster.The influence of several variables such as the hydrochloric acid concentration in both metals adsorption and the addition of thiocyanate and dioxan

M Iglesias; E Anticó; V Salvadó

1999-01-01

422

Electrically conductive resinous bond and method of manufacture  

DOEpatents

A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40.degree. to 365.degree. C. to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.

Snowden, Jr., Thomas M. (P.O. Box 4231, Clearwater, FL 33518); Wells, Barbara J. (865 N. Village Dr., Apt. 101B, St. Petersburg, FL 33702)

1987-01-01

423

Technique for removing resin from a molded object  

NASA Technical Reports Server (NTRS)

Resin is removed from a molded object in such a way that no cracks or expansion occurs in the casting. The resin is first mixed with a ceramics powder or metal powder. This mixture is then molded and the resin is removed by heat. The molded object is then placed into a container which is sealed and large enough to allow the gas from the resin to be controlled by heat from the resin. The gas pressure at the surface of the object is increased by the gas pressure generated from the resin and the resin removed. The increase in gas pressure from the surface of the molded object is 1.5 atm to 3 atm at 350 C to 400 C.

Hemmi, I.; Morishita, T.; Ono, T.

1983-01-01

424

Electrically conductive resinous bond and method of manufacture  

DOEpatents

A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40 to 365/sup 0/C to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.

Snowden, T.M. Jr.; Wells, B.J.

1985-01-01

425

Study on the resin temperature developments during UV imprinting process.  

PubMed

During the imprinting process, the temperature of the UV resin increases as the phase of the resin changes from fluid into solid. During UV curing, some amount of heat is released from inside the resin and transferred into contacting materials. The heat flow is measured with photo-DSC, and other related thermal and mechanical properties of the resin. With the measured material properties, the temperature developments both inside of the resin layer and along the interfaces of the contacting materials are computed. During the UV exposure period, the thermal deformation of the mold, which directly influences the pattern distortion are investigated. Under this condition, the developments of strain and temperature inside the mold structure including the UV resin of 3-D shape are computed with the transient time scale during UV curing according to the thickness of resin layer. These computational results are expected to provide useful information for better designs of the imprinting mold and the process condition. PMID:22629908

Jeon, Jongduk; Jang, Siyoul

2012-02-01

426

Uranium Adsorption on Ion-Exchange Resins - Batch Testing  

SciTech Connect

The uranium adsorption performance of five resins (Dowex 1, Dowex 21K 16-30 [fresh], Dowex 21K 16-30 [regenerated], Purofine PFA600/4740, and ResinTech SIR-1200) were tested using unspiked, nitrate-spiked, and nitrate-spiked/pH adjusted source water from well 299-W19-36. These batch tests were conducted in support of a resin selection process in which the best resin to use for uranium treatment in the 200-West Area groundwater pump-and-treat system will be identified. The results from these tests are as follows: • The data from the high-nitrate (1331 mg/L) tests indicated that Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 all adsorbed uranium similarly well with Kd values ranging from ~15,000 to 95,000 ml/g. All four resins would be considered suitable for use in the treatment system based on uranium adsorption characteristics. • Lowering the pH of the high nitrate test conditions from 8.2 to 7.5 did not significantly change the uranium adsorption isotherms for the four tested resins. The Kd values for these four resins under high nitrate (1338 mg/L), lower pH (7.5) ranged from ~15,000 to 80,000 ml/g. • Higher nitrate concentrations greatly reduced the uranium adsorption on all four resins. Tests conducted with unspiked (no amendments; nitrate at 337 mg/L and pH at 8.2) source water yielded Kd values for Dowex 1, Dowex 21K 16-30 (fresh), Purofine PFA600/4740, and ResinTech SIR-1200 resins ranging from ~800,000 to >3,000,000 ml/g. These values are about two orders of magnitude higher than the Kd values noted from tests conducted using amended source water. • Compared to the fresh resin, the regenerated Dowex 21K 16-30 resin exhibited significantly lower uranium-adsorption performance under all test conditions. The calculated Kd values for the regenerated resin were typically an order of magnitude lower than the values calculated for the fresh resin. • Additional testing using laboratory columns is recommended to better resolve differences between the adsorption abilities of the resins and to develop estimates of uranium loading on the resins. By determining the quantity of uranium that each resin can adsorb and the time required to reach various levels of loading, resin lifetime in the treatment system can be estimated.

Mattigod, Shas V.; Golovich, Elizabeth C.; Wellman, Dawn M.; Cordova, Elsa A.; Smith, Ronald M.

2010-12-01

427

1,3-dioxolyl acetals as powerful crosslinkers of phenolic resin  

NASA Astrophysics Data System (ADS)

The principle of chemical amplification has proven to be successful for the design of highly sensitive, high resolution resist materials of both positive and negative tone, respectively. This paper discusses our new approach to a high resolution, aqueous base developable deep-UV negative tone resist. It is based on the acid catalyzed cleavage of acetal blocked aromatic aldehydes, which, if treated with strong Broensted acid, react with the surrounding phenolic resin in a Friedel-Crafts type reaction, thereby leading to matrix crosslinking. Resists based on this type of crosslinking chemistry show good deep-UV transparency, have high sensitivity, and can be developed with an aqueous base.

Schaedeli, Ulrich P.; Muenzel, Norbert; Holzwarth, Heinz E.

1993-09-01

428

Plasma treatment increased shear bond strength between heat cured acrylic resin and self-curing acrylic resin.  

PubMed

Self-curing acrylic resin is generally used for the repair of a fractured denture base. However, re-fracture of the repaired denture base resin often occurs because of poor bonding strength between the base resin and self-curing repair resin. The effect of plasma treatment on the shear bond strength between heat cured acrylic resin and the self-cured acrylic was examined. It was revealed that plasma irradiation is effective in increasing the shear bond strength. Plasma irradiation does not cause environmental pollution, as it does not require chemicals. It is a useful method to increase adhesive strength between heat cured acrylic resin and self-curing acrylic resin. PMID:14641672

Nishigawa, G; Maruo, Y; Oka, M; Oki, K; Minagi, S; Okamoto, M

2003-11-01

429

Bond strength of resin cement to zirconia ceramic with different surface treatments.  

PubMed

Zirconia-based ceramics offer strong restorations in dentistry, but the adhesive bond strength of resin cements to such ceramics is not optimal. This study evaluated the influence of surface treatments on the bond strength of resin cement to yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic. Seventy-five plates of Y-TZP ceramic were randomly assigned to five groups (n = 15) according to the surface treatments [airborne particle abrasion, neodymium-doped yttrium aluminum garnet (Nd:YAG) laser irradiation (Fidelis Plus 3, Fotona; 2 W, 200 mJ, 10 Hz, with two different pulse durations 180 or 320 ?s), glaze applied, and then 9.5 % hydrofluoric acid gel conditioned, control]. One specimen from each group was randomly selected, and specimens were evaluated with x-ray diffraction and SEM analysis. The resin cement (Clearfil Esthetic Cement, Kuraray) was adhered onto the zirconia surfaces with its corresponding adhesive components. Shear bond strength of each sample was measured using a universal testing machine at a crosshead speed of 1 mm/min. Bond strengths were analyzed through one-way ANOVA/Tukey tests. Surface treatments significantly modified the topography of the Y-TZP ceramic. The Nd:YAG laser-irradiated specimens resulted in both increased surface roughness and bond strength of the resin cement. The highest surface roughness and bond strength values were achieved with short pulse duration. Nd:YAG laser irradiation increased both surface roughness of Y-TZP surfaces and bond strength of resin cement to the zirconia surface. PMID:22718473

Usumez, Asl?han; Hamdemirci, Nermin; Koroglu, Bilge Yuksel; Simsek, Irfan; Parlar, Ozge; Sari, Tugrul

2013-01-01

430

Levulinic acid production based on extrusion and pressurized batch reaction  

Microsoft Academic Search

Levulinic acid is a highly versatile chemical with numerous industrial uses, having the potential to become a commodity chemical. It can be used as a raw material for resins, plasticizers, textiles, animal feed, coatings and antifreeze. Starches and sugars are typically converted to levulinic acid using a batch reactor. Blends of corn starch (70%), sulfuric acid (5%), and water (25%)

J. Y Cha; M. A Hanna

2002-01-01

431

Selective concentration of aromatic bases from water with a resin adsorbent  

USGS Publications Warehouse

Aromatic bases are concentrated from water on columns of a resin adsorbent and recovered by aqueous-acid elution. The degree of concentration attainable depends on the ratio of the capacity factor (k) of the neutral form of the amine to that of the ionized form. Capacity factors of ionic forms of amines on XAD-8 resin (a methylacrylic ester polymer) are greater than zero, ranging from 20 to 250 times lower than those of their neutral forms; they increase with increasing hydrophobicity of the amine. Thus, desorption by acid is an edition (k during desorption >0) rather than a displacement (k during desorption = 0) process. The degree of concentration attainable on XAD-8 resin varies with the hydrophobicity of the amine, being limited for hydrophilic solutes (for example, pyridine) by small neutral-form k's, reaching a maximum for amines of intermediate hydrophobicity (for example, quinoline), and decreasing for more hydrophobc solutes (for example, acridine) because of their large ionic-form k's.

Stuber, H.A.; Leenheer, J.A.

1983-01-01

432

Ethynylated aromatics as high temperature matrix resins  

NASA Technical Reports Server (NTRS)

Difunctional and trifunctional arylacetylenes were used as monomers to form thermoset matrix resin composites. Composites can be hot pressed at 180 C to react 80 percent of the acetylene groups. Crosslinking is completed by postcuring at 350 C. The postcured resins are thermally stable to nominally 460 C in air. As a result of their high crosslink density, the matrix exhibits brittle failure when unaxial composites are tested in tension. Failure of both uniaxial tensile and flexural specimens occurs in shear at the fiber matrix interface. Tensile fracture stresses for 0 deg composites fabricated with 60 v/o Celion 6K graphite fiber were 827 MPa. The strain to failure was 0.5 percent. Composites fabricated with 8 harness satin Celion cloth (Fiberite 1133) and tested in tension also failed in shear at tensile stresses of 413 MPa.

Hurwitz, Frances I.

1986-01-01

433

Process for manufacturing a petroleum resin  

SciTech Connect

The present invention relates to a process for manufacturing a petroleum resin wherein a fraction (Component a) containing an aromatic hydrocarbon obtained by cracking of petroleum and a thermally polymerized oil (Component b) obtained by previously thermal-polymerizing the component a are mixed and then the mixture of the components a and B is subjected to polymerization by employing a Friedel-Crafts catalyst. It is also directed to propose a petroleum resin of a superior quality having a softening point optionally in a range of 30-120/sup 0/C and various bromine value in such a manner that a mixing ratio of the components a and B is properly adjusted.

Iwashita, T.; Nagano, M.; Tanaka, K.

1981-08-11

434

Flammability of Epoxy Resins Containing Phosphorus  

NASA Technical Reports Server (NTRS)

As part of a program to develop fire-resistant exterior composite structures for future subsonic commercial and general aviation 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 neat epoxy formulations were characterized by thermogravimetric analysis, propane torch test, elemental analysis, microscale combustion calorimetry, and fire calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness and compressive strength of several cured formulations showed no detrimental effect due to phosphorus content. The chemistry and properties of these new epoxy formulations are discussed.

Hergenrother, P. M.; Thompson, C. M.; Smith, J. G.; Connell, J. W.; Hinkley, J. A.

2005-01-01

435

Controlled catalytic and thermal sequential pyrolysis and hydrolysis of phenolic resin containing waste streams to sequentially recover monomers and chemicals  

DOEpatents

A process of using fast pyrolysis in a carrier gas to convert a waste phenolic resin containing feedstreams in a manner such that pyrolysis of said resins and a given high value monomeric constituent occurs prior to pyrolyses of the resins in other monomeric components therein comprising: selecting a first temperature program range to cause pyrolysis of said resin and a given high value monomeric constituent prior to a temperature range that causes pyrolysis of other monomeric components; selecting, if desired, a catalyst and a support and treating said feedstreams with said catalyst to effect acid or basic catalyzed reaction pathways to maximize yield or enhance separation of said high value monomeric constituent in said first temperature program range to utilize reactive gases such as oxygen and steam in the pyrolysis process to drive the production of specific products; differentially heating said feedstreams at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantity of said high value monomeric constituent prior to pyrolysis of other monomeric components therein; separating said high value monomeric constituent; selecting a second higher temperature program range to cause pyrolysis of a different high value monomeric constituent of said phenolic resins waste and differentially heating said feedstreams at said higher temperature program range to cause pyrolysis of said different high value monomeric constituent; and separating said different high value monomeric constituent.

Chum, Helena L. (Arvada, CO); Evans, Robert J. (Lakewood, CO)

1992-01-01

436

Characterisation and discrimination of various types of lac resin using gas chromatography mass spectrometry techniques with quaternary ammonium reagents.  

PubMed

A variety of lac resin samples obtained from artists' suppliers, industrial manufacturers, and museum collections were analysed using gas chromatography mass spectrometry (GCMS) and reactive pyrolysis GCMS with quaternary ammonium reagents. These techniques allowed a detailed chemical characterisation of microgram-sized samples, based on the detection and identification of derivatives of the hydroxy aliphatic and cyclic (sesquiterpene) acids that compose the resin. Differences in composition could be related to the nature of the resin, e.g. wax-containing (unrefined), bleached, or aged samples. Furthermore, differences in the relative abundances of aliphatic hydroxyacids appear to be associated with the biological source of the resin. The diagnostic value of newly characterised lac components, including 8-hydroxyacids, is discussed here for the first time. Identification of derivatised components was aided by AMDIS deconvolution software, and discrimination of samples was enhanced by statistical evaluation of data using principal component analysis. The robustness of the analyses, together with the minimal sample size required, make these very powerful approaches for the characterisation of lac resin in museum objects. The value of such analyses for enhancing the understanding of museum collections is illustrated by two case studies of objects in the collection of the Philadelphia Museum of Art: a restorer's varnish on a painting by Luca Signorelli, and a pictorial inlay in an early nineteenth-century High Chest by George Dyer. PMID:24642395

Sutherland, K; del Río, J C

2014-04-18

437

Determination of 232Th in seawater by ICP-MS after preconcentration and separation using a chelating resin.  

PubMed

This article describes an analytical method for the separation, preconcentration and determination of (232)Th in seawater samples at sub-ng/L levels using a NOBIAS CHELATE PA1 resin and a sector field (SF) inductively coupled plasma mass spectrometer (ICP-MS). The resin showed excellent adsorption of (232)Th at a low pH of 2.4 ± 0.4 in a relatively small volume (200 mL) of seawater. (232)Th adsorbed on the resin was easily eluted using 5 mL of 0.8M HNO(3). An enrichment factor of 40 was achieved for (232)Th analysis. Ethylenediamine-tetraacetic acid disodium salt dehydrate (EDTA) was used to investigate the effect of (232)Th-binding organic ligand on the retention of (232)Th on the chelating resin. Results obtained using acidified samples (pH of 2.4 ± 0.4) showed EDTA had no significant effect on (232)Th recovery, indicating that at this low pH, (232)Th was dissociated from the (232)Th-binding organic ligand and quantitatively retained on the NOBIAS CHELATE PA1 resin. The developed analytical method was characterized by a separation and preconcentration taking approximately 4h and a low detection limit of 0.0038 ng/L for (232)Th, and was successfully applied to the determination of (232)Th in seawater samples collected from coastal areas, Japan. PMID:21872017

Takata, Hyoe; Zheng, Jian; Tagami, Keiko; Aono, Tatsuo; Uchida, Shigeo

2011-09-30

438

Anion-exchange resin-based desulfurization process. Final report  

SciTech Connect

The following investigations were performed: (1) batch mode screening of eleven(11) commercially available resins and selection of three candidate resins for further evaluation in a fixed-bed setup. (2) Process variables study using three candidate resins in the fixed-bed setup and selection of the ``best`` resin for process economics development. (3) Exhaustion efficiency and solution concentration were found to be inversely related necessitating a trade-off between the resin cost versus the cost of evaporation/concentration of ensuing effluents. (4) Higher concentration of the HCO{sub 3}{sup {minus}} form of active sites over less active CO{sub 3}{sup 2{minus}} form of sites in the resin was believed to be the main reason for the observed increase in the equilibrium capacity of the resin at an elevated static CO{sub 2}-pressure. This Increase in capacity was found to level off around 80--120 psig range. The increase in CO{sub 2}-pressure, however, did not appear to affect the overall ion-exchange kinetics. (5) In the fixed-bed mode, the solution concentration was found to affect the equilibrium capacity of candidate resins. Their relationship was well satisfied by the Langmuir type non-linear equilibrium isotherm. Alternatively, the effect of solution concentration on overall ion-exchange kinetics varied from resin to resin. (6) Product inhibition effect on the resin was observed as an initial increase followed by a significant decrease in the resin`s equilibrium capacity for SO{sub 4}{sup 2{minus}} as the HCO{sub 3}{sup {minus}}/SO{sub 4}{sup 2{minus}} molar ratio in the solution was increased from 0 to 1.0. This ratio, however, did not affect the overall ion-exchange kinetics.

Sheth, A C; Dharmapurikar, R; Strevel, S D

1994-01-01

439

Potential contribution of exposed resin to ecosystem emissions of monoterpenes  

NASA Astrophysics Data System (ADS)

Conifers, especially pines, produce and store under pressure monoterpene-laden resin in canals located throughout the plant. When the plants are damaged and resin canals punctured, the resin is exuded and the monoterpenes are released into the atmosphere, a process that has been shown to influence ecosystem-level monoterpene emissions. Less attention has been paid to the small amounts of resin that are exuded from branches, expanding needles, developing pollen cones, and terminal buds in the absence of any damage. The goal of this study was to provide the first estimate of the potential of this naturally-exposed resin to influence emissions of monoterpenes from ponderosa pine (Pinus ponderosa) ecosystems. When resin is first exuded as small spherical beads from undamaged tissues it emits monoterpenes to the atmosphere at a rate that is four orders of magnitude greater than needle tissue with an equivalent exposed surface area and the emissions from exuded beads decline exponentially as the resin dries. We made measurements of resin beads on the branches of ponderosa pine trees in the middle of the growing season and found, on average, 0.15 cm2 of exposed resin bead surface area and 1250 cm2 of total needle surface area per branch tip. If the resin emerged over the course of 10 days, resin emissions would make up 10% of the ecosystem emissions each day. Since we only accounted for exposed resin at a single point in time, this is probably an underestimate of how much total resin is exuded from undamaged pine tissues over the course of a growing season. Our observations, however, reveal the importance of this previously unrecognized source of monoterpenes emitted from pine forests and its potential to influence regional atmospheric chemistry dynamics.

Eller, Allyson S. D.; Harley, Peter; Monson, Russell K.

2013-10-01

440

Candida albicans adhesion to composite resin materials  

Microsoft Academic Search

The adhesion of Candida albicans to dental restorative materials in the human oral cavity may promote the occurrence of oral candidosis. This study aimed\\u000a to compare the susceptibility of 14 commonly used composite resin materials (two compomers, one ormocer, one novel silorane,\\u000a and ten conventional hybrid composites) to adhere Candida albicans. Differences in the amount of adhering fungi should be

Ralf Bürgers; Wulf Schneider-Brachert; Martin Rosentritt; Gerhard Handel; Sebastian Hahnel

2009-01-01

441

Ion Exchange Resins Transforming Drug Delivery Systems.  

PubMed

Ion-exchange resins are light, porous, three-dimensional high molecular weight cross -linked matrix of hydrocarbon chains carrying positively or negatively charged sites that can attract an ion of opposite charge from the surrounding medium. There is stoichiometric exchange of mobile ions between the solid and the solution called as Ion-exchange which does not lead to any radical change in the properties and structure of the solid. Depending upon the type of Ionexchanged it can be either Cation-exchange or Anion-exchange. They are prepared in the form of granules, beads or sheets. As drug delivery systems they have received considerable attention after the 1950s due to their inertness, freedom from side effects, high drug loading capacity, ease of sterilization and the fact that their structure can be easily altered to achieve the desired drug release characteristics. Their use is revolutionizing all traditional delivery systems namely- oral, nasal, ophthalmic and parenteral. Ion- exchange resins have been used for the development of novel drug delivery systems (NDDSs), to modify the characteristics of the dosage form and various other biomedical applications. The present article deals with the varied applications of ion-exchange resins for taste making, as resinates (simple and microencapsulated or coated), Pennkinetic systems, in selective recovery of pharmaceuticals, in pH and ionic strength responsive systems, in gastro-retentive systems, in hollow fiber systems, as sigmoidal release systems, as site specific delivery systems and as inotophoretically assisted transdermal drug delivery systems. They also have an immense importance when used as disintegrants/ superdisintegrants in formulation of orodispersible tablets, powder processing aids and in the dissolution and stabilization of drugs. PMID:20497105

Gupta, Shweta; Benien, Parul; Sahoo, P K

2010-05-24

442

Ion Exchange Resins Transforming Drug Delivery Systems.  

PubMed

Ion-exchange resins are light, porous, three-dimensional high molecular weight cross -linked matrix of hydrocarbon chains carrying positively or negatively charged sites that can attract an ion of opposite charge from the surrounding medium. There is stoichiometric exchange of mobile ions between the solid and the solution called as Ion-exchange which does not lead to any radical change in the properties and structure of the solid. Depending upon the type of Ion-exchanged it can be either Cation-exchange or Anion-exchange. They are prepared in the form of granules, beads or sheets. As drug delivery systems they have received considerable attention after the 1950s due to their inertness, freedom from side effects, high drug loading capacity, ease of sterilization and the fact that their structure can be easily altered to achieve the desired drug release characteristics. Their use is revolutionizing all traditional delivery systems namely- oral, nasal, ophthalmic and parenteral. Ion- exchange resins have been used for the development of novel drug delivery systems (NDDSs), to modify the characteristics of the dosage form and various other biomedical applications. The present article deals with the varied applications of ion-exchange resins for taste making, as resinates (simple and microencapsulated or coated), Pennkinetic systems, in selective recovery of pharmaceuticals, in pH and ionic strength responsive systems, in gastro-retentive systems, in hollow fiber systems, as sigmoidal release systems, as site specific delivery systems and as inotophoretically assisted transdermal drug delivery systems. They also have an immense importance when used as disintegrants / superdisintegrants in formulation of orodispersible tablets, powder processing aids and in the dissolution and stabilization of drugs. PMID:20158479

Gupta, Shweta; Parul; Sahoo, P K

2010-02-17

443

Fire- and Heat-Resistant Laminating Resins  

NASA Technical Reports Server (NTRS)

Imide compounds containing phosphourus thermally polymerized. New maleimido- or citraconimido-end-capped monomers, have relatively low melting temperatures, polymerized at moderate temperatures to rigid bisimide resins without elimination of volatiles. Monomers dissolve in such solvents as methyl ethyl ketone, acetone, and tetrahydrofuran, suitable and perferred as "varnish solvents" for composite fabrication. Low melting points of these componds allow use as adhesives without addition of solvents.

Kourtides, Demetrius A.; Mikroyannidis, John A.

1987-01-01

444

Light color, low softening point hydrocarbon resins  

Microsoft Academic Search

This patent describes a hydrocarbon resin having a softening point of from 0° C to about 40° C, a Gardner color of about 7 or less, a number average molecular weight (Mn) of from about 100 to about 600, and a M{sub {ital w}}\\/M{sub {ital n}} ratio of from about 1.1 to about 2.7, prepared by Friedel Crafts polymerization of

M. L. Evans; S. G. Hentges

1990-01-01

445

Glutathione Resins I. List of Components  

E-print Network

-1) Purchase of the GST Purification Kit provides sufficient reagents for performing five batch/gravity flow Clontech · www.clontech.com · 800-662-2566 #12;GlutathioneResinProtocol · Polypropylene tubes · Centrifuge (pre-chilled to 4ºC) · TALONTM 2-ml Disposable Gravity Columns (#8903-1) · Deionized H2O · Ice · Column

Lebendiker, Mario

446

Ceramic whisker reinforcement of dental resin composites.  

PubMed

Resin composites currently available are not suitable for use as large stress-bearing posterior restorations involving cusps due to their tendencies toward excessive fracture and wear. The glass fillers in composites provide only limited reinforcement because of the brittleness and low strength of glass. The aim of the present study was to reinforce dental resins with ceramic single-crystalline whiskers of elongated shapes that possess extremely high strength. A novel method was developed that consisted of fusing silicate glass particles onto the surfaces of individual whiskers for a two-fold benefit: (1) to facilitate silanization regardless of whisker composition; and (2) to enhance whisker retention in the matrix by providing rougher whisker surfaces. Silicon nitride whiskers, with an average diameter of 0.4 microm and length of 5 microm, were coated by the fusion of silica particles 0.04 microm in size to the whisker surface at temperatures ranging from 650 degrees C to 1000 degrees C. The coated whiskers were silanized and manually blended with resins by spatulation. Flexural, fracture toughness, and indentation tests were carried out for evaluation of the properties of the whisker-reinforced composites in comparison with conventional composites. A two-fold increase in strength and toughness was achieved in the whisker-reinforced composite, together with a substantially enhanced resistance to contact damage and microcracking. The highest flexural strength (195+/-8 MPa) and fracture toughness (2.1+/-0.3 MPa x m(1/2)) occurred in a composite reinforced with a whisker-silica mixture at whisker:silica mass ratio of 2:1 fused at 800 degrees C. To conclude, the strength, toughness, and contact damage resistance of dental resin composites can be substantially improved by reinforcement with fillers of ceramic whiskers fused with silica glass particles. PMID:10029470

Xu, H H; Martin, T A; Antonucci, J M; Eichmiller, F C

1999-02-01

447

Metallic-resin compounds fuel processing process  

Microsoft Academic Search

In a demonstration plant for the recycling of post-use electric home appliances, the authors developed a metal-resin compounds fuel processing system for generated plastics and shredder dusts from this recycling plant. In this system, waste plastics and other shredder dust is thermally cracked in an oxygen-free rotary carbonization reactor with a maximum rate of 250 kg\\/h. Most of the plastic

H. Hoshina; T. Hayanose

1999-01-01

448

Thermochemical study of behavior of petroleum resins  

Microsoft Academic Search

The stability of petroleum disperse systems and the structural-mechanical properties of these systems are determined mainly by the presence of high-molecular-weight waxes, asphaltenes, and resins, which form complex structural units (CSUs) in the system. The influence of the energy of intermolecular interaction (IMI) on the formation of associates has not yet been thoroughly evaluated, although an important role has been

E. N. Sazonova; M. Yu. Mashkov; A. A. Velikov; N. V. Yudina

1988-01-01

449

Composition of acid tars from sulfuric acid treatment of petroleum oils  

Microsoft Academic Search

In the production of distillate and residual lube oils, the lube stocks may be treated with concentrated sulfuric acid or oleum. This removes unsaturates, aromatics, sulfur compounds, nitrogen compounds and resinous substances, all of which are materials that lower the stability and have a detrimental effect on the service indexes of commercial petroleum oils. Acid tar is formed as a

A. F. Frolov; T. S. Titova; I. V. Karpova; T. L. Denisova

1985-01-01

450

Sulfur geochemistry of hydrothermal waters in Yellowstone National Park, Wyoming, USA. III. An anion-exchange resin technique for sampling and preservation of sulfoxyanions in natural waters  

USGS Publications Warehouse

A sampling protocol for the retention, extraction, and analysis of sulfoxyanions in hydrothermal waters has been developed in the laboratory and tested at Yellowstone National Park and Green Lake, NY. Initial laboratory testing of the anion-exchange resin Bio-Rad??? AG1-X8 indicated that the resin was well suited for the sampling, preservation, and extraction of sulfate and thiosulfate. Synthetic solutions containing sulfate and thiosulfate were passed through AG1-X8 resin columns and eluted with 1 and 3 M KCl, respectively. Recovery ranged from 89 to 100%. Comparison of results for water samples collected from five pools in Yellowstone National Park between on-site IC analysis (U.S. Geological Survey mobile lab) and IC analysis of resin-stored sample at SUNY-Stony Brook indicates 96 to 100% agreement for three pools (Cinder, Cistern, and an unnamed pool near Cistern) and 76 and 63% agreement for two pools (Sulfur Dust and Frying Pan). Attempts to extract polythionates from the AG1-X8 resin were made using HCl solutions, but were unsuccessful. Bio-Rad??? AG2-X8, an anion-exchange resin with weaker binding sites than the AG1-X8 resin, is better suited for polythionate extraction. Sulfate and thiosulfate extraction with this resin has been accomplished with KCl solutions of 0.1 and 0.5 M, respectively. Trithionate and tetrathionate can be extracted with 4 M KCl. Higher polythionates can be extracted with 9 M hydrochloric acid. Polythionate concentrations can then be determined directly using ion chromatographic methods, and laboratory results indicate recovery of up to 90% for synthetic polythionate solutions using AG2-X8 resin columns. ?? The Royal Society of Chemistry and the Division of Geochemistry of the American Chemical Society 2003.

Druschel, G.K.; Schoonen, M.A.A.; Nordstorm, D.K.; Ball, J.W.; Xu, Y.; Cohn, C.A.

2003-01-01

451

Sulfur geochemistry of hydrothermal waters in Yellowstone National Park, Wyoming, USA. III. An anion-exchange resin technique for sampling and preservation of sulfoxyanions in natural waters  

PubMed Central

A sampling protocol for the retention, extraction, and analysis of sulfoxyanions in hydrothermal waters has been developed in the laboratory and tested at Yellowstone National Park and Green Lake, NY. Initial laboratory testing of the anion-exchange resin Bio-Rad™ AG1-X8 indicated that the resin was well suite