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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.

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

2012-06-18

3

Phosphonic acid based exchange resins  

DOEpatents

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

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

1995-01-01

4

Phosphonic acid based ion exchange resins  

DOEpatents

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

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

1996-01-01

5

Phosphonic acid based ion exchange resins  

DOEpatents

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

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

1994-01-01

6

21 CFR 176.110 - Acrylamide-acrylic acid resins.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

7

Immobilization of glyoxylic acid on Wang resin  

Microsoft Academic Search

We report herein the simple preparation of immobilized glyoxylic acid, where the acid function is either linked through an amide or an ester bond to Wang resin. These compounds represent interesting aldehyde inputs for the generation of new libraries of small molecules.

Nathalie Schlienger; Martin R Bryce; Thomas K Hansen

2000-01-01

8

Antimicrobial activity of resin acid derivatives  

Microsoft Academic Search

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

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

2006-01-01

9

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...

2010-01-01

10

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

Code of Federal Regulations, 2010 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...

2009-04-01

11

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...

2013-04-01

12

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

PubMed

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

Mendez, R; Pillai, V N

1990-06-01

13

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

14

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

Microsoft Academic Search

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

Kiran Bhise; Shafi Shaikh; Divyakumar Bora

2008-01-01

15

New polystyrene sulfonic acid resin catalysts with enhanced acidic and catalytic properties  

Microsoft Academic Search

The effects of halogenation of polystyrene sulfonic acid resins on acidic and catalytic properties have been evaluated. Four polystyrene-co-divinylbenzene sulfonic acid resins from Rohm and Haas (Amberlyst 70, Amberlyst 15, Amberlyst 35 and Amberlyst 36) have been characterised in terms of their acidities (both strength and acid site concentrations) by ammonia adsorption flow microcalorimetry, their thermal and hydrothermal stabilities, and

P. F. Siril; H. E. Cross; D. R. Brown

2008-01-01

16

Enhanced vanillin production from ferulic acid using adsorbent resin  

Microsoft Academic Search

High vanillin productivity was achieved in the batch biotransformation of ferulic acid by Streptomyces sp. strain V-1. Due to the toxicity of vanillin and the product inhibition, fed-batch biotransformation with high concentration\\u000a of ferulic acid was unsuccessful. To solve this problem and improve the vanillin yield, a biotransformation strategy using\\u000a adsorbent resin was investigated. Several macroporous adsorbent resins were chosen

Dongliang Hua; Cuiqing Ma; Lifu Song; Shan Lin; Zhaobin Zhang; Zixin Deng; Ping Xu

2007-01-01

17

Biomimetic Remineralization of Resin-bonded Acid-etched Dentin  

PubMed Central

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

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

2009-01-01

18

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

Microsoft Academic Search

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

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

19

Comparative value of fatty acids and resin acids of tall oil in soaps  

Microsoft Academic Search

Summary  A study has been made of the detergency and foaming power of soaps made from a typical acid-refined American tall oil. Sodium\\u000a soap of tall oil, straight tall oil fatty-acid soap, and straight tall oil resin-acid soap were evaluated. The effect of fatty\\u000a acid-resin acid ratio was determined by using mixtures of those soaps. Sodium rosinate, sodium oleate, and mixtures

Foster Dee Snell; Irving Reich

1950-01-01

20

Treatment of DSD acid wastewater using a weak basic resin  

Microsoft Academic Search

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

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

2005-01-01

21

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

22

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

Microsoft Academic Search

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

Seiichi Yasuda; Kyoko Asano

2000-01-01

23

Fatty and resinic acids extractions from crude tall oil  

SciTech Connect

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

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

1996-11-01

24

Oxidation-resistant acidic resins prepared by partial carbonization as cocatalysts in synthesis of adipic acid.  

PubMed

The oxidation-resistant acidic resins are of great importance for the catalytic oxidation systems. In this paper, the oxidatively stable acidic resins are obtained from the cation ion exchange resins (CIERs) through the thermal treatment in N(2) atmosphere. The structure and properties of the thermally treated CIERs were characterized by chemical analysis, Fourier transform infrared (FT-IR) spectra, acid capacity measurement and scanning electron microscope (SEM). The thermally treated CIERs possess high acid capacity up to 4.09 mmol g(-1). A partial carbonization is observed in the thermal treatment process of CIERs, but the morphology of resin spheres maintains well. The as-prepared CIERs are used as solid acids to assist the hydrogen peroxide oxidation of cyclohexene to adipic acid (ADA) with tungstic acid as the catalyst precursor. The improved yields of ADA in the recycling reaction are obtained in the presence of acidic CIERs. Meanwhile, the unproductive decomposition of H(2)O(2) is effectively suppressed. The high yields of ADA (about 81%) are kept by the thermally treated CIERs even after the fifth cycle. The thermally treated CIERs exhibit excellent acid-catalytic performance and possess remarkable oxidation-resistant capability. PMID:22775061

Wei, Huijuan; Li, Hongbian; Liu, Yangqing; Jin, Peng; Wang, Xiangyu; Li, Baojun

2012-07-20

25

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

26

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

27

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

Microsoft Academic Search

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

Vu Hong Thang; Senad Novalin

2008-01-01

28

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

29

Storage of polyacid-modified resin composites (“compomers”) in lactic acid solution  

Microsoft Academic Search

Objectives: The aim of this study was to determine the interaction of four polyacid-modified resin composites with aqueous lactic acid solutions, and to compare changes with those for a glass-ionomer cement and a conventional resin composite.Methods: For each material, namely Compoglass F, Dyract AP, Hytac and Ana Compomer, plus AquaCem (glass-ionomer cement) and Pekafil (conventional composite resin), five cylindrical specimens

J. W. Nicholson; B. J. Millar; B. Czarnecka; H. Limanowska-Shaw

1999-01-01

30

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

Microsoft Academic Search

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

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

2000-01-01

31

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

Microsoft Academic Search

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

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

1979-01-01

32

Ultrastructural characteristics of glial fibrillary acidic protein expression in epoxy resin-embedded human brain tumors  

Microsoft Academic Search

Thirteen surgically removed, epoxy resin (Durcupan ACM or Epon 812)-embedded human brain tumors were examined for glial fibrillary acidic protein (GFAP) content in semithin and ultrathin sections with the immunogold-silver staining method. Mild aldehyde fixation and the hydrophobic resin embedding did not interfere with the antigenicity, since silver intensification of the immunogold marker provided excellent visualization of the reaction on

B. Bozóky; T. Krenács; Zs. Rázga; A. Erd?s

1993-01-01

33

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

Microsoft Academic Search

A new composite cation exchanger, tamarind sulphonic acid (TSA) resin has been synthesized. The chemically modified TSA ion exchange resin has been used for the removal and preconcentration of Zn, Cd, Fe, Co and Cu ions in aqueous solution and effluent from the Laxmi steel plant in Jodhpur, India. This type of composite represents a new class of hybrid ion

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

2012-01-01

34

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

Microsoft Academic Search

A new composite cation exchanger, tamarind sulphonic acid (TSA) resin has been synthesized. The chemically modified TSA ion exchange resin has been used for the removal and preconcentration of Zn, Cd, Fe, Co and Cu ions in aqueous solution and effluent from the Laxmi steel plant in Jodhpur, India. This type of composite represents a new class of hybrid ion

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

2011-01-01

35

Recovery of uranium from phosphoric acid solutions using chelating ion-exchange resins  

SciTech Connect

In fertilizer manufacture, calcium phosphate in phosphate rock is rendered soluble by sulfuric acid attack. The phosphoric acid obtained in this way usually contains 26%--28% P{sub 2}O{sub 5}. Several novel processes have been developed for the recovery of uranium from wet-process phosphoric acid. Experimental measurements have been made on the batch extraction of uranium from phosphoric acid solutions using various chelating ion-exchange resins (RSPO, Diaion-CRP200, Diphonix, Purolite S940, Duolite ES467, and Lewatit OC 1060) and a solvent containing ion-exchange resins (Actinide-CU). The kinetic performance of ion-exchange resins was compared, and the effect of Fe(II) and Ca(II) ions on the sorption and elution performance has also been examined. The results showed that the resin Actinide-CU containing a diphosphonate extractant was very effective for removing uranium from phosphoric acid solution. However, the elution performance of this resin with both acid and carbonate eluants was poor. It is concluded that the chelating resins Diphonix, Duolite ES467, Lewatit OC 1060, and Purolite S940 give reasonable sorption of uranium in the presence of Fe(II) ions in batch sorption trials. The desorption of uranium has been performed quantitatively using carbonate eluants. Purolite S940 was used in small-scale column extractions of uranium from phosphoric acid solutions, and promising loading/elution profiles were obtained.

Kabay, N.; Demircioglu, M.; Yayh, S.; Guenay, E.; Yueksel, M.; Saglam, M. [Ege Univ., Bornova (Turkey). Dept. of Chemical Engineering; Streat, M. [Loughborough Univ. (United Kingdom). Dept. of Chemical Engineering

1998-05-01

36

Improved gas chromatographic analysis of fatty and resin acid mixtures with special reference to tall oil  

Microsoft Academic Search

and Summary  A gas liquid chromatography system for the analysis of complex mixtures of fatty and resin acids has been developed. On 30–40\\u000a m long, 0.3 mm ID glass capillary columns coated with 1,4-butanediol succinate (BDS) and attaining over 90,000 effective theoretical\\u000a plates, all main fatty and resin acids in wood extractives and various tall oil products can be separated and

B. Holmbom

1977-01-01

37

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

Microsoft Academic Search

The formation of water-soluble organic ligands by radiolytic and chemical degradation of several strong acidic ion-exchange resins was investigated under conditions close to those of the near field of a cementitious repository. The most important degradation products were studied and their complexing properties evaluated. Irradiation of strong acidic cation exchange resins (Powder PCH and Lewatite S-100) resulted in the formation

L. R. van Loon; W. Hummel

1999-01-01

38

SuperLig(TM) 644 Ion Exchange Resin Stability in Nitric Acid at Elevated Temperatures  

Microsoft Academic Search

In the Hanford River Protection Project Waste Treatment Plan (RPP-WTP) flowsheet, opportunity exists for the organic SuperLig 644(TM) cation exchange resin to come in contact with concentrated (5 M) nitric acid at elevated temperatures in the acid recovery evaporator. These are similar conditions where other ion exchange resin (albeit usually anion) column explosions have occurred. The objective of these tests

2003-01-01

39

CHEMICAL ANALYSIS OF HIGH ASH BRAZILIAN COAL TAR. 2. ACID\\/BASIC\\/NEUTRAL SEPARATION OF RESINS  

Microsoft Academic Search

Resins, obtained by chromatographic separation on silica-gel as described in a previous work (Lanças and Caramão, 1992), were fractionated by acid\\/basic\\/neutral separation in modified silica gel (acidic and basic) and characterized by infrared and elemental analysis. Resins were the major components found in the preparative liquid chromatographic fractionation of coal tar, and, for this reason, we tried to fractionated them

Fernando Mauro Lanças; Elina Bastos Caramão

1996-01-01

40

Adsorption behavior and mechanism of amino methylene phosphonic acid resin for Ag(I)  

Microsoft Academic Search

The sorption properties of amino methylene phosphonic resin(APAR) for Ag(I) were studied. The amino methylene phosphonic acid resin(APAR) has a good adsorption ability for Ag(I) at pH=6.0 in the HAc-NaAc medium. The statically saturated adsorption capacity is 272 mg\\/g resin, Ag(I) adsorbed on APAR can be eluted by 5% (NH2)2CS-0.5 mol\\/L hydrochloric acid quantitatively. The adsorption rate constants determined under

Zeng-Nian SHU; Chun-Hua XIONG; Xu WANG

2006-01-01

41

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

Microsoft Academic Search

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

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

2008-01-01

42

REMOVAL OF ACETIC ACID IMPURITIES FROM ETHYL ACETATE BY ADSORPTION ON ION EXCHANGE RESINS  

Microsoft Academic Search

Removal of acetic acid impurities from ethyl acetate was attempted by sorption on basic ion-exchange resins. Kinetic studies showed that acid removal is controlled by intraparticle resistance from both ethyl acetate and alcohol. Breakthrough curves for uptake of the acid from ethyl acetate were obtained at different flow rates and concentrations. Desorption studies were performed using both ethyl acetate and

H. M. Anasthas; V. G. Gaikar

2001-01-01

43

Chemical Modification of Polystyrene. VI. Thermal Stability Studies of Sulfonic Acid Resins from Anhydride Modified Polystyrene  

Microsoft Academic Search

Thermal stabilities of the H form of sulfonic acid resins from polystyrene electrophilically substituted with phthalic anhydride, pyro-mellitic dianhydride, trimellitic anhydride, and cis-1,2,3,6-tetra-hydrophthalic anhydride have been studied and compared by DTA and TGA. Isothermal degradation studies of these resins at 150 ± 10°C for 72 h in air and nitrogen reveal significant changes in IR, decreases in sulfur content, and

Mukul Biswas; Shakuntala Chatterjee

1984-01-01

44

Effects of Saturated Acids on Physical Properties of UPE Resins Prepared from Recycled PET Products  

Microsoft Academic Search

In this study, effects of saturated acids on physical properties, including hardness, impact strength, flexural properties\\u000a and thermal properties, of unsaturated polyester or UPE resins prepared from recycled PET bottles and fabrics were investigated.\\u000a PET was depolymerized by glycolysis reaction with the excess propylene glycol in the presence of zinc acetate as a catalyst.\\u000a UPE resins were then synthesized by

K. Puangsansuk; M. Opaprakasit; W. Udomkichdecha; P. Potiyaraj

2009-01-01

45

Kinetics study on separation of cadmium from tellurium in acidic solution media using ion-exchange resins  

Microsoft Academic Search

The feasibility of using ion-exchange resins to separate cadmium from tellurium in acidic solutions of the two metals was investigated. We studied the competitive adsorption of cadmium and tellurium in such resins under varying acid strengths and contact time. We found that low sulfuric acid strength (i.e., 0.5M) was most effective in removing cadmium from solutions. Different ion-exchange resins were

Wenming Wang; Vasilis Fthenakis

2005-01-01

46

Sorption of curium, berkelium, californium, and einsteinium on cation exchange resin from nitric acid solutions  

Microsoft Academic Search

Plots of the distribution coefficients of curium, berkelium, einsteinium, and californium (+3 ions) adsorbed on Dowex 50-X8 resin from nitric acid solutions are U-shaped, while plots of einsteinium (+4 ions) distribution coefficients are similar to an exponential decay curve. The +3 ions exhibit a minimum sorption at a nitric acid concentration of 6 or 7 molar. (LK)

1976-01-01

47

Exposure to acid anhydrides in three resin and one cushioned flooring manufacturing plants.  

PubMed

Acid anhydrides are reactive organic chemicals of low molecular weight which cause occupational asthma. No previous research on the relationship between exposure to these chemicals and respiratory sensitization and development of occupational asthma has been reported. A retrospective cohort study was carried out in four factories (three alkyd resin factories and one cushioned flooring factory) to investigate the nature of exposure-response relationships for sensitization to phthalic anhydride (PA), trimellitic anhydride (TMA) and maleic anhydride (MA). This paper describes the results of full-shift and task-specific exposure measurements. Exposure to PA was low in relation to the Occupational Exposure Standard (OES). The highest full-shift PA exposures occurred among resin operators in the resin factory that used solid PA as compared to other resin factories where liquid PA was used. Arithmetic mean exposure levels to TMA and MA in the resin factories were well below their respective OESs. Short-term high exposures occurred during loading of acid anhydrides into the reactors and sampling and testing of the resin. Relatively high full-shift exposure to TMA occurred in the cushioned flooring factory, although no high peak exposures were detected. PMID:8526391

van Tongeren, M J; Barker, R D; Gardiner, K; Harris, J M; Venables, K M; Taylor, A J; Harrington, J M

1995-10-01

48

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

49

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

SciTech Connect

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

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

1999-06-01

50

Influence of a peracetic acid-based immersion on indirect composite resin.  

PubMed

The aim of this study was to evaluate the influence of immersion in a 0.2% peracetic acid-based disinfectant on the three-point flexural strength, water sorption and water solubility of an indirect composite resin. Specimens were produced according to ISO 4049:2000 specifications and were divided in two groups: Control group, with no disinfection and Disinfected group, with three 10 min immersions in the peracetic acid intercalated with 10 min immersions in sterile distilled water. All evaluations were conducted in compliance with ISO specifications. Three-point flexural strength, water sorption and solubility of indirect composite resin before and after immersion showed no statistical significant differences (p > 0.05) and met ISO standard requirements. Immersion in peracetic acid solution showed no influence in indirect composite resin tested properties. PMID:21780726

Samuel, Susana Maria Werner; Fracaro, Gisele Baggio; Collares, Fabrício Mezzomo; Leitune, Vicente Castelo Branco; Campregher, Ulisses Bastos

2011-06-01

51

Explosion hazards of ion exchange resin mixed with perchloric acid  

Microsoft Academic Search

On January 21, 2003, an explosion occurred while ion exchange resin (IER) was being used to separate impurities from uranium\\u000a solution. To clarify the cause of the accident and go\\/no-go criteria of the explosion, elemental analysis of the IER, DSC\\u000a analysis, and SIKAREX analysis (a screening tool for runaway reactions) were performed. Finally, experiments on the same scale\\u000a as the

Ken Okada; Miyako Akiyoshi; Atsumi Miyake; Terushige Ogawa; Mitsuo Nomura; Takehiro Matsunaga

2009-01-01

52

Ion-Exchange Studies in the Removal of Polybasic Acids. Anomalous Sorption Behavior of Phosphoric Acid on Weak Base Resins  

Microsoft Academic Search

Sorption behavior of phosphoric acid on the weak base resins Amberlite IRA-93 and Dowex WGR-2 is reported. Studies on sorption equilibria and dynamics reveal anomalous sorption behavior as compared to sorption of strong and weak monobasic acids. A mathematical treatment is developed to correlate the experimental data on sorption dynamics. An alternative type of mechanism is also proposed based on

V. M. Bhandari; V. A. Juvekar; S. R. Patwardhan

1997-01-01

53

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

Microsoft Academic Search

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

Yasuyuki Matsushita; Seiichi Yasuda

2003-01-01

54

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

55

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

Microsoft Academic Search

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

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

1997-01-01

56

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

PubMed

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

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

57

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

PubMed

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

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

2008-01-01

58

Selective sorption of alkali-metal cations by carboxylic acid resins containing acyclic or cyclic polyether units  

SciTech Connect

Novel ion-exchange resins have been prepared by condensation polymerization with formaldehyde in formic acid of three polyether carboxylic acids which possess two benzo group substituents. The selectivities and efficiencies of competitive alkali-metal cation sorption from aqueous solutions by these polyether carboxylic acid resins are strongly influenced by (1) the pH of the aqueous solution, (2) the acyclic or cyclic nature of the polyether unit, and (3) the conformational positioning of the carboxylic acid group in the resins derived from cyclic polyether (crown ether) compounds. Good sorption selectivity for Na{sup +} was observed for dibenzo-16-crown-5 resin 3 in which the pendant carboxylic acid group is oriented over the polyether cavity. Resin 3 was utilized as a stationary phase for selective column concentration of Na{sup +} from dilute aqueous solution.

Hayashita, Takashi; Goo, Mija; Lee, Jong Chan; Kim, Jong Seung; Krzykawski, J.; Bartsch, R.A. (Texas Tech Univ., Lubbock (USA))

1990-11-01

59

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

Microsoft Academic Search

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

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

2005-01-01

60

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

61

Polyaniline-doped benzene sulfonic acid\\/epoxy resin composites: structural, morphological, thermal and dielectric behaviors  

Microsoft Academic Search

Conducting polymer composites, which are simply physical mixtures of an insulating polymer matrix and intrinsically conducting polymers, are promising new materials for various applications such as antistatic coatings, shielding and electromagnetic absorbers. In this context, a novel conducting composite was successfully produced. It is based on epoxy resin and polyaniline (PANI) doped in benzene sulfonic acid, which was used as

Belkacem Belaabed; Saad Lamouri; Nacera Naar; Patrice Bourson; Sidi Ould Saad Hamady

2010-01-01

62

[Novel method to observe the interface between adhesive resin and dentin by staining Fe3+ with tannic acid].  

PubMed

The reaction of Fe3+ and tannic acid was used in a new visual method to confirm the Fe3+ incorporated with dentin during the pretreatment with a 10% citric acid-3% ferric chloride solution or EDTA ferric ammonium salt solution. The combination of Fe3+ and tannic acid was also effective to investigate the state of incorporated resin (resin tags and resin reinforced dentin) with the dentin. The adhered dentin treated by staining with tannic acid was examined. The incorporation of Fe3+ with dentin enhanced the monomer infiltration and resulted in a high bond strength. Addition of 4-META into the MMA-TBB resin increased the resin content in dentin by promoting the rate of monomer diffusion. PMID:1725831

Takarada, K; Nikaidou, T; Kojima, M; Nakabayashi, N

1990-05-01

63

Kinetics of Ethyl Acetate Synthesis Catalyzed by Acidic Resins  

ERIC Educational Resources Information Center

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

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

2011-01-01

64

Using resin supported nano zero-valent iron particles for decoloration of Acid Blue 113 azo dye solution  

Microsoft Academic Search

In this study, a synthesized cation exchange resin supported nano zero-valent iron (NZVI) complex forming NZVI–resin was proposed for the decoloration of an azo dye Acid Blue 113 (AB 113), taking into account reaction time, initial dye concentration, NZVI dose and pH. From results, the successful decoloration of the AB 113 solution was observed using a NZVI–resin. Increasing the iron

Hung-Yee Shu; Ming-Chin Chang; Chi-Chun Chen; Po-En Chen

2010-01-01

65

The Use of an Intermediate Resin in the Acid-etch Procedure: Retentive Strength, Microleakage, and Failure Mode Analysis  

Microsoft Academic Search

Three composite resin systems, one conventional (Concise) and two microfilled (IsoPast and Silar), used with and without an intermediate resin (Concise Enamel Bond), were evaluated with and without thermal stress for in vitro retentive strength and sealing ability to acid-etched human enamel.All three materials yielded significantly different shear strength values. The use of an intermediate resin significantly improved both the

A. P. Prevost; J. L. Fuller; L. C. Peterson

1982-01-01

66

Ion-exchange properties of a salicylic acid–melamine–formaldehyde terpolymer resin  

Microsoft Academic Search

Terpolymer resins, synthesized by the condensation of salicylic acid and melamine with formaldehyde in the presence of an acid catalyst, proved to be a selective chelating ion-exchange polymer for certain metals. The chelating ion-exchange properties of this polymer were studied for Cu2+, Ni2+, Co2+, Zn2+, Fe3+, Cd2+ and Pb2+ ions. A batch equilibrium method was employed in the study of

Wasudeo B Gurnule; H. D Juneja; L. J Paliwal

2002-01-01

67

Encapsulated Fatty Acids in an Acrylic Resin as Shape-stabilized Phase Change Materials for Latent Heat Thermal Energy Storage  

Microsoft Academic Search

This article aims to prepare novel shape-stabilized phase change materials (PCMs) by encapsulating fatty acids (stearic acid [SA], palmitic acid [PA], and myristic acid [MA]) as a PCM in an acrylic resin (Eudragit E) as supporting material and to determine latent heat thermal energy storage (LHTES) properties. The maximum percentage of all fatty acids in the shape-stabilized PCMs was found

K. Kaygusuz; C. Alkan; A. Sari; O. Uzun

2008-01-01

68

Paraffin isomerization, paraffin disproportionation, and benzene alkylation catalyzed by aluminum chloride/sulfonic acid resins  

SciTech Connect

The catalytic isomerization of n-butane at 298/sup 0/-413/sup 0/K and n-pentane at 343/sup 0/-413/sup 0/K in a packed-bed flow reactor at 1 atm in the presence of aluminum chloride/sulfonic acid resin was accompanied by disproportionation and cracking. The selectivity to isomerization products was approx. 40% for n-pentane and > 99% for n-butane. Kinetics of n-butane isomerization at 308/sup 0/-338/sup 0/K were determined by using a partially deactivated catalyst batch, and the dependence of the isomerization rate on the partial pressure of n-butane was fitted using a power-law or a Langmuir-Hinshelwood rate equation. Alkylations of benzene with propylene catalyzed by sulfonic acid resin at 328/sup 0/K and aluminum chloride/sulfonic acid resin at 295/sup 0/K gave isopropylbenzene and mono- to tetra-isopropylbenzenes, respectively. A catalyst deactivation model was developed and used to correlate the time-dependent behavior of n-butane isomerization and benzene propylation. The data indicated that Broensted acid sites are responsible for the activity of the supported aluminum chloride catalyst.

Fuentes-Zurita, G.A.

1980-01-01

69

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

70

Detoxification of Wheat Straw Hydrolysis in Formic Acid Reaction System by D311 Ion-exchange Resin  

Microsoft Academic Search

Formic acid hydrolysis is widely used in lignocellulose pretreatment. However, formic acid hydrolysis wheat straw cannot be directly used as a fermentation substrate owing to various fermentation inhibitors, especially the formic acid in reaction system and released during pretreatment. Study found treatment of wheat straw hydrolysate with D311 ion-exchange resin had a good result on reduction formic acid. We investigated

Junping Zhuang; Lu Lin; Chunsheng Pang; Zhen Wu; Ying Liu

2010-01-01

71

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

Microsoft Academic Search

The voltage-sensitive sodium channel present in the eel (Electrophorus electricus) has an unusually high content of sialic acid, including α-(2â8)-linked polysialic acid, not found in other electroplax membrane glycopeptides. Lectins from Limax flavus (LFA) and wheat germ (WGA) proved the most effective of 11 lectin resins tried. The most selective resin was prepared from IgM antibodies against Neisseria meningitidis α-(2â8)-polysialic

William M. James; Mark C. Emerick; William S. Agnew

1989-01-01

72

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

73

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

SciTech Connect

Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selected for use in the Hanford Waste Treatment and Immobilization Plant (WTP). It is also the primary ion exchange material under consideration for SCIX at the Hanford site. The elution step of the multi-step ion exchange process is typically done with 0.5 M nitric acid. An acid eluant is a potential hazard in the event of a spill, leak, etc. because the high-level waste tanks are made of carbon steel. Corrosion and associated structural damage may ensue. A study has been conducted to explore non-acid elution as an alternative. Batch contact sorption equilibrium screening tests have been conducted with 36 potential non-acid eluants. The sorption tests involve equilibrating each cesium-containing eluant solution with the sRF resin for 48 hours at 25 C in a shaker oven. In the sorption tests, an eluant is deemed to have a high cesium elution potential if it minimizes cesium sorption onto the sRF resin. The top candidates (based on lowest cesium sorption distribution coefficients) include ammonium carbonate, ammonium carbonate/ammonium hydroxide, ammonium bicarbonate, rubidium carbonate, ammonium acetate, ammonium acetate/ammonium hydroxide, ammonium bicarbonate/ammonium hydroxide, calcium chloride, and magnesium chloride. A select few of the top candidate eluants from the screening tests were subjected to actual sorption (loading) and elution tests to confirm their elution ability. The actual sorption (loading) and elution tests mimicked the typical sRF-cesium ion exchange process (i.e., sorption or loading, caustic wash, water rinse, and elution) via batch contact sorption and quasi column caustic wash/water rinse/elution. The eluants tested included ammonium carbonate, ammonium acetate, calcium acetate, magnesium acetate, and nitric acid. Calcium acetate and magnesium acetate were substitutes for calcium chloride and magnesium chloride respectively due to corrosion concerns. Nitric acid was selected for benchmarking since it is the baseline cesium eluant for sRF resin. The cesium elution performance of ammonium carbonate and ammonium acetate was approximately the same as the benchmark eluant, nitric acid. Ninety-seven (97), 94, and 100% percent of the cesium sorbed or loaded were eluted by ammonium carbonate, ammonium acetate, and nitric acid was respectively. The performance of calcium acetate and magnesium acetate, on the other hand, was mediocre. Percent elution was 16 and 8 respectively.

Adu-Wusu, K.; Pennebaker, F.

2010-12-22

74

Comparison of the apical seal obtained by a dual-cure resin based cement or an epoxy resin sealer with or without the use of an acidic primer.  

PubMed

This study compared the apical leakage of roots obturated with gutta-percha using either a dual-cure resin based cement (Panavia F) or an epoxy-resin sealer (Thermaseal plus) with or without the application of an acidic primer (ED Primer). Eighty-six single rooted canine teeth were decoronated, cleaned, and shaped by using hand and rotary instruments, randomly divided into four groups, and obturated as follows: group A (n = 20): ED Primer applied followed by thermoplastized obturation with gutta-percha and Thermaseal Plus sealer; group B (n = 20): thermoplastized obturation with gutta-percha and Thermaseal Plus; group C (n = 20): ED primer applied followed by thermoplastized obturation with gutta-percha and Panavia F; group D (n = 20): thermoplastized obturation with gutta-percha and Panavia F. Both a negative control (n = 3; entire root coated with wax) and a positive control (n = 3; obturated with only a fitted master cone) were included in the study. Groups A, B, C, D, and the controls were immersed in molten sticky wax, leaving the apical 2-mm exposed, and quickly chilled. All teeth were immersed in 1% methylene blue dye solution for 10 days, rinsed, and sectioned longitudinally. Apical dye penetration was measured stereomicroscopically at 10-fold magnification. The analysis of variance and Duncan Multiple Range were used for result analysis. The specimens obturated with gutta-percha and an epoxy-resin sealer (with or without an acidic primer) demonstrated significantly less linear dye penetration than specimens obturated with gutta-percha and the dual-cure, resin-based cement (with or without an acidic primer). PMID:12398172

Britto, Leandro R; Borer, Robert E; Vertucci, Frank J; Haddix, James E; Gordan, Valeria V

2002-10-01

75

Retene and resin acid concentrations in sediment profiles of a lake recovering from exposure to pulp mill effluents  

Microsoft Academic Search

The stratigraphy of resin acids (pimaric, isopimaric, sandaracopimaric, dehydroabietic and abietic acids) and base neutral compounds (retene, tetrahydroretene, dehydroabietin and fichtelite) in sediments of a lake recovering after the mill closure from exposure to effluents from sulphite pulp mill was studied. The highest concentrations of these compounds were detected 1.5 km downstream from the effluent pipe in sediment depth of

Harri Leppänen; Aimo Oikari

2001-01-01

76

Removal of metal ions from the complexed solutions in fixed bed using a strong-acid ion exchange resin  

Microsoft Academic Search

Fixed bed removal of equimolar metal ions (Co2+, Ni2+, Mn2+, Sr2+) from aqueous solutions using a strong-acid resin was examined. The solution contained a water-soluble complexing agent including ethylenediaminetetraacetic acid, nitrilotriacetic acid, and citric acid. Experiments were performed under different solution pH and molar concentration ratios of complexing agent to the total metals. It was shown from batch studies that

Ruey-Shin Juang; Su-Hsia Lin; Tsung-Yuan Wang

2003-01-01

77

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

2012-12-28

78

Cancer chemopreventive effects and cytotoxic activities of the triterpene acids from the resin of Boswellia carteri.  

PubMed

Fifteen triterpene acids, viz., seven of the beta-boswellic acids (ursane-type) (1-7), two of the alpha-boswellic acids (oleanane-type) (8, 9), two of the lupeolic acids (lupane-type) (10, 11), and four of the tirucallane-type (12-14, 16), and two cembrane-type diterpenes (17, 18), isolated from the MeOH extract of the resin of Boswellia carteri (Burseraceae), together with a triterpene acid 15 (the acetyl derivative of 14), were examined for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells and on activation of (+/-)-(E)-methyl-2[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitrogen oxide (NO) donor, and cytotoxic activities against three human neuroblastoma cell lines, IMR-32, NB-39, and SK-N-SH in vitro. On evaluation against the EBV-EA activation induced by TPA, seven compounds, 2, 10, 11, and 13-16, showed potent inhibitory effects on EBV-EA induction. Upon evaluation against activation of NOR 1, five compounds, 7, 13, and 14-16, showed potent inhibitory effects. Further, fifteen compounds, 1-7, 9-11, 13-15, 17, and 18, exhibited potent cytotoxic activities with IC(50) values of 4.1-82.4 muM against all of the three human neuroblastoma cells tested. PMID:16946522

Akihisa, Toshihiro; Tabata, Keiichi; Banno, Norihiro; Tokuda, Harukuni; Nishimura, Reiko; Nishihara, Reiko; Nakamura, Yuji; Kimura, Yumiko; Yasukawa, Ken; Suzuki, Takashi

2006-09-01

79

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

2008-09-02

80

Taste mask, design and evaluation of an oral formulation using ion exchange resin as drug carrier.  

PubMed

The purpose of this research was to mask the bitter taste of Diphenhydramine Hydrochloride (DPH) using cation exchange resins. Indion 234 and Tulsion 343 that contained crosslinked polyacrylic backbone were used. The drug resin complexes (DRC) were prepared by batch process by taking drug: resin ratios 1:1, 1:2, and 1:3. The optimum drug: resin ratio and the time required for maximum complexation was determined. The drug resinates were evaluated for the drug content, taste, micromeritic properties drug release and X-ray diffraction (PXRD). Effervescent and dispersible tablets were developed from optimum drug: resin ratios of 1:2 and 1:1. The formulations were evaluated for uniformity of dispersion, disintegration time, and in vitro dissolution. The X-ray diffraction study confirmed the monomolecularity of entrapped drug in the resin beads. The taste evaluation depicted the successful taste masking of DPH with drug resin complexes. The drug release of 95% in 15 min was observed for effervescent and dispersible tablets. PMID:18491233

Bhise, Kiran; Shaikh, Shafi; Bora, Divyakumar

2008-05-06

81

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

PubMed Central

The purpose of this research was to mask the bitter taste of Diphenhydramine Hydrochloride (DPH) using cation exchange resins. Indion 234 and Tulsion 343 that contained crosslinked polyacrylic backbone were used. The drug resin complexes (DRC) were prepared by batch process by taking drug: resin ratios 1:1, 1:2, and 1:3. The optimum drug: resin ratio and the time required for maximum complexation was determined. The drug resinates were evaluated for the drug content, taste, micromeritic properties drug release and X-ray diffraction (PXRD). Effervescent and dispersible tablets were developed from optimum drug: resin ratios of 1:2 and 1:1. The formulations were evaluated for uniformity of dispersion, disintegration time, and in vitro dissolution. The X-ray diffraction study confirmed the monomolecularity of entrapped drug in the resin beads. The taste evaluation depicted the successful taste masking of DPH with drug resin complexes. The drug release of 95% in 15 min was observed for effervescent and dispersible tablets.

Shaikh, Shafi; Bora, Divyakumar

2008-01-01

82

Extraction and Separation of Zirconium(IV) and Hafnium(IV) from Chloride Media Using Magnetic Resin with Phosphoric Acid Functionality  

Microsoft Academic Search

Glycidyl methacrylate\\/divinylbenzene (GMA\\/DVB) resin modified by embedded magnetite was prepared. The resin was immobilized with phosphoric acid functionality and used to recover Zr(IV) and Hf(IV) from aqueous solutions using batch and column techniques. The resin obtained was investigated by means of infrared (IR), x-ray diffraction (XRD), and environmental scanning electron microscope ESEM. The measurements showed that the particles of Fe3O4

A. M. Donia; A. A. Atia; A. M. Daher; E. A. Elshehy

2011-01-01

83

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

Microsoft Academic Search

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

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

2007-01-01

84

Synthesis and Characterization of Polyacrylamide-Acrylic Acid Resin and Its Use for Treatment of Radioactive Liquid Waste  

Microsoft Academic Search

The cationic resin of polyacrylamide-acrylic acid “pAM–AA” was prepared by gamma radiation–induced polymerization of acrylic acid “AA” in presence of polyacrylamide “pAM” using a template polymerization technique. The product materials were characterized by powder x-ray diffraction, and infrared spectra.The ion-exchange capacity for Cu, Co, Cs ions decreases with increasing the hydrogen ion concentration. The ion selectivity decreases in the order

T. Siyam; M. M. Abdel-Hamid; I. M. El-Naggar

1995-01-01

85

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

PubMed

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

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

2008-12-15

86

Application of ion exchange resin in floating drug delivery system.  

PubMed

The purpose of this study was to explore the application of low-density ion exchange resin (IER) Tulsion(R) 344, for floating drug delivery system (FDDS), and study the effect of its particle size on rate of complexation, water uptake, drug release, and in situ complex formation. Batch method was used for the preparation of complexes, which were characterized by physical methods. Tablet containing resin with high degree of crosslinking showed buoyancy lag time (BLT) of 5-8 min. Decreasing the particle size of resin showed decrease in water uptake and drug release, with no significant effect on the rate of complexation and in situ complex formation for both preformed complexes (PCs) and physical mixtures (PMs). Thus, low-density and high degree of crosslinking of resin and water uptake may be the governing factor for controlling the initial release of tablet containing PMs but not in situ complex formation. However, further sustained release may be due to in situ complex formation. PMID:18777244

Upadhye, Abhijeet A; Ambike, Anshuman A; Mahadik, Kakasaheb R; Paradkar, Anant

2008-10-01

87

Synthetic Transformations of Resin Acids. IX. Certain Derivatives of 12-Br-Dehydroabietic Acid.  

National Technical Information Service (NTIS)

The authors attempted to produce anologs of gibberellins - potential plant growth regulators - from 12-Br-dehydroabietic acid. As a result of the synthetic transformation of 12-Br-dehydroabietic acid, 12-Br-6,7-diketomethyl dehydroabietate, 6 Br-1,2,3,4,1...

M. I. Goryaev F. S. Sharipova L. K. Tikhonova L. A. Elchibekova E. B. Popova

1972-01-01

88

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

PubMed Central

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

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

2012-01-01

89

Epoxy resin sand consolidation rejuvenation  

Microsoft Academic Search

A process is described for increasing the strength and stability of an epoxy resin-consolidated permeable mass of grains that has been weakened by a resin- degradative aqueous liquid. The mud acids, which comprise aqueous solutions of acidic materials that contain (or form) hydrofluoric acid, are particularly strong resin-degradative aqueous liquids. A consolidated permeable mass of grains that contains an epoxy

T. W. Jr. Hamby; W. T. Jr. Strickland

1972-01-01

90

Effect of acidic primers on adhesive bonding of tri-n-butylborane initiated adhesive resin to alumina.  

PubMed

The present study was conducted to evaluate the effect of acidic primers on adhesive bonding to sintered alumina. Alumina disk specimens were primed with one of the following acidic materials: Acryl Bond, All Bond II Primer B, Alloy Primer, Estenia Opaque Primer, Eye Sight Opaque Primer, M.L. Primer, MR. Bond, and Super-Bond Liquid. The disks were bonded with an adhesive resin (Super-Bond) initiated with a tri-n-butylborane (TBB) derivative, and bond strengths were determined. Average bond strength before thermocycling varied from 42.9 to 44.3 MPa, whereas post-thermocycling bond strength ranged from 22.0 to 42.8 MPa. Of the nine groups assessed, reduction of bond strength after thermocycling was not significant in three: Alloy Primer, Estenia Opaque Primer, and Eye Sight Opaque Primer. It can be concluded that phosphate-based primers are recommended for bonding sintered alumina with Super-Bond resin. PMID:21206159

Koizumi, Hiroyasu; Nakayama, Daisuke; Oba, Yusuke; Yamada, Kazuya; Matsumura, Hideo

2010-12-01

91

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

92

Acetyl11-keto-ß-boswellic acid, a constituent of a herbal medicine from Boswellia serrata resin, attenuates experimental ileitis  

Microsoft Academic Search

The gum resin extract from Boswellia serrata (H15), an herbal product, was recently shown to have positive therapeutic effects in inflammatory bowel disease (IBD). However, the mechanisms and constituents responsible for these effects are poorly understood. This study examined the effect of the Boswellia extract and its single constituent acetyl-11-keto-#-boswellic acid (AKBA) on leukocyte-endothelial cell interactions in an experimental model

Christian F. Krieglstein; Christoph Anthoni; Emile J. M. Rijcken; Mike Laukötter; Hans-Ulrich Spiegel; Sven E. Boden; Stephan Schweizer; Hasan Safayhi; Norbert Senninger; Guido Schürmann

2001-01-01

93

Adsorption and removal of As(V) and As(III) using Zr-loaded lysine diacetic acid chelating resin  

Microsoft Academic Search

An adsorption process for the removal of As(V) and As(III) was evaluated under various conditions using zirconium(IV) loaded chelating resin (Zr-LDA) with lysine-N?,N? diacetic acid functional groups. Arsenate ions strongly adsorbed in the pH range from 2 to 5, while arsenite was adsorbed between pH 7 and 10.5. The sorption mechanism is an additional complexation between arsenate or arsenite and

Tatineni Balaji; T. Yokoyama; Hideyuki Matsunaga

2005-01-01

94

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

PubMed

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

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

1997-10-17

95

Evaluation of resin and fatty acid concentration levels by online sample enrichment followed by atmospheric pressure chemical ionization-mass spectrometry (APCI-MS)  

Microsoft Academic Search

Background, aim, and scope  In papermaking, there is a continuous interest both to minimize fresh water consumption and to reduce discharges into the\\u000a environment. These general trends mean an increase in the amounts of detrimental substances, such as resin and fatty acids,\\u000a in papermaking process waters. Resin acids, in particular, are responsible for much of the toxicity typically present in paper

Piia Valto; Juha Knuutinen; Raimo Alén

2009-01-01

96

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

Microsoft Academic Search

Heats of ionization by thermometric titration for a series of bases (or acids) can be used to compare solid acids (or bases) with liquid analogues bearing the same functionalities in homogeneous solutions. The method is demonstrated for Broensted acids by reacting a series of substituted nitrogen bases with solutions of p-toluenesulfonic acid (PTSA) in acetonitrile and with suspensions of the

Edward M. Arnett; Rebecca A. Haaksma; B. Chawla; Marguerite H. Healy

1986-01-01

97

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

98

A novel extractant-impregnated resin containing carminic acid for selective separation and pre-concentration of uranium(VI) and thorium(IV)  

Microsoft Academic Search

The present work proposes the use of a novel extractant-impregnated resin (EIR) as an adsorbent in trace separation and pre-concentration of U(VI) and Th(IV) ions. The new EIR was prepared by impregnating carminic acid onto Amberlite XAD-16 resin beads. The morphology of new EIR was studied by BET surface area measurements and SEM micrographs. A column packed with CA\\/XAD-16 was

Ahmad Hosseini-Bandegharaei; Mohammad Saeid Hosseini; Yousef Jalalabadi; Mehdi Nedaie; Masoud Sarwghadi; Akram Taherian; Esmat Hosseini

2011-01-01

99

Synthesis and characterization of a new resin functionalized with 2-naphthol-3,6-disulfonic acid and its application for the speciation of chromium in natural water  

Microsoft Academic Search

A polystyrene divinyl benzene (8%) copolymer has been functionalized by coupling it through ?N?N? group with 2-naphthol-3,6-disulfonic acid (NDSA). The resulting resin has been characterized by elemental analysis, thermogravimetric analysis and infrared spectra. The hydrogen ion, water regain and metal ion capacities of the resin have been determined. Two forms of chromium show different exchange capacities at different pH values,

Bhim Chandra Mondal; Debasis Das; Arabinda K. Das

2002-01-01

100

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

Microsoft Academic Search

The purpose of this study was to selectively remove chromium and copper from CCA-treated wood acid leachates (initial concentrations of 447–651mg As l?1, 374–453mg Cu l?1 and 335–622mg Cr l?1) using ion exchange resins and precipitation techniques. Batch experiments revealed that the chelating resin Dowex M4195 had a high copper selectivity in the presence of chromium while the Amberlite IR120

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

2009-01-01

101

Enhancing solid phase synthesis by a noncovalent protection strategy-efficient coupling of rhodamine to resin-bound peptide nucleic acids  

Microsoft Academic Search

Resins for solid-phase synthesis can affect coupling efficiencies by interacting with reactants. We have observed that polyethylene glycol-polystyrene (PEG-PS) solid support absorbs added activated fluorophores, preventing efficient labeling of peptide nucleic acids (PNAs). We now report that addition of an inexpensive unactivated fluorophore blocks the resin and allows efficient labeling. This protection strategy may have general benefits for peptide and

Lynn D. Mayfield; David R. Corey

1999-01-01

102

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

PubMed

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

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

1999-05-01

103

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

SciTech Connect

Small-column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions are among the waste treatment plans in the DOE-complex. Spherical Resorcinol-Formaldehyde (sRF) is the ion exchange resin selected for use in the Hanford Waste Treatment and Immobilization Plant (WTP). It is also the primary ion exchange material under consideration for SCIX at the Hanford site. The elution step of the multi-step ion exchange process is typically done with 0.5 M nitric acid. An acid eluant is a potential hazard in the event of a spill, leak, etc. because the high-level waste tanks are made of carbon steel. Corrosion and associated structural damage may ensue. Studies are ongoing to explore non-acid elution as an alternative. Batch contact sorption equilibrium screening tests have been conducted with 36 potential non-acid eluants. The sorption tests involve equilibrating each cesium-containing eluant solution with the sRF resin for 48 hours at 25 C in a shaker oven. In the sorption tests, an eluant is deemed to have a high cesium elution potential if it minimizes cesium sorption onto the sRF resin. The top candidates (based on lowest cesium sorption distribution coefficients) include ammonium carbonate, ammonium carbonate/ammonium hydroxide, ammonium bicarbonate, rubidium carbonate, ammonium acetate, ammonium acetate/ammonium hydroxide, ammonium bicarbonate/ammonium hydroxide, calcium chloride, and magnesium chloride. The next phase of testing for this work will focus on the following down selected eluants: Ammonium carbonate, ammonium acetate, calcium acetate, magnesium acetate, nitric acid, and ammonium hydroxide. The next testing phase is a confirmation of the elution ability of the selected eluants. It will mimic a typical sRF cesium ion exchange process i.e., sorption or loading, caustic wash, water rinse, and elution via batch contact sorption and quasi column caustic wash/water rinse/elution. Due to corrosion concerns, calcium acetate and magnesium acetate will be tested instead of calcium chloride and magnesium chloride respectively. Nitric acid is for benchmarking since it is the baseline sRF eluant. The information at hand indicates ammonium hydroxide, while a weak base, may hold promise as an effective eluant. Hence, its inclusion among the eluants to be studied despite the fact that it was not tested as a stand-alone eluant earlier.

Adu-Wusu, K.; Pennebaker, F.

2010-09-01

104

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

Code of Federal Regulations, 2012 CFR

...Nitrate *Ethylene-Methacrylic Acid Copolymers *Ethylene-Vinyl Acetate Copolymers *Fatty Acid Resins *Fluorocarbon Polymers Nylon 11 Resin *Nylon 6-66 Copolymers *Nylon 6âNylon 11 Blends Nylon 6 Resin Nylon 612 Resin Nylon 66...

2012-07-01

105

Input to Resin Column Structural Analysis if Autocatalytic Resin Reaction Occurs in HB-Line Phase II  

Microsoft Academic Search

Solutions of plutonium in nitric acid are purified and concentrated using anion resin prior to precipitation. There have been instances of resin column explosions caused by autocatalytic reactions of anion resins in nitric acid within the DOE complex

Hallman

2001-01-01

106

Enhanced adsorption and antifouling performance of anion-exchange resin by the effect of incorporated Fe3O4 for removing humic acid.  

PubMed

The application of anion-exchange resins (AERs) is limited by fouling, which increases the fresh resin dosage, regeneration frequency, and amount of regeneration effluent. In this study, five AERs with different Fe3O4 amounts was prepared by increasing the amount of Fe3O4 added to 100 g of monomer mixture for suspension polymerization from 0 g to 40 g. Results showed considerably improved pore volume and hydrophilicity of the resin with increased Fe3O4 content, leading to significantly enhanced adsorption and desorption of humic acid. A method of developing novel resins with enhanced adsorption and antifouling abilities by incorporating Fe3O4 was then proposed. The adsorbent structure resulting from the incorporated inorganic particles was found to be important in determining the adsorption behavior of a hybrid adsorbent. PMID:24011841

Shuang, Chendong; Wang, Mengqiao; Zhou, Qing; Zhou, Weiwei; Li, Aimin

2013-08-19

107

Influence of calcium hydroxide dressing and acid etching on the push-out bond strengths of three luting resins to root canal dentin.  

PubMed

OBJECTIVES: This study aims to investigate the effects of calcium hydroxide (Ca(OH)2) dressing in root canals and the effects of subsequent acid etching on the adhesion of luting resins to root canals. MATERIALS AND METHODS: Root specimens were prepared from extracted human permanent molars. Specimen canals were (1) filled with etch-and-rinse (Nexus® third generation (NX3)) and two self-adhesive (RelyX Unicem, Maxcem Elite) luting resins, respectively; (2) dressed with Ca(OH)2 before Ca(OH)2 removal and luting resin filling; (3) dressed with Ca(OH)2 before Ca(OH)2 removal and post-cementation; or (4) treated as described in item (2) except that the canals were further etched with phosphoric acid before luting resin filling. Push-out bond strengths were measured and analyzed using one-way analysis of variance, and Fisher's multiple comparison tests provided a follow-up comparison among these four canal treatments. Attenuated total reflectance-Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) were used to analyze the specimen surfaces. RESULTS: Ca(OH)2 dressing adversely affected the bond strengths to canal dentin of the three luting resins tested. Acid etching did not increase the bond strengths. Infrared analysis revealed that Ca(OH)2 dressing caused no structural changes on the dentin surface. XPS and SEM analyses revealed Ca(OH)2 remnants as the ultimate chemical cause leading to the decrease in bond strength. CONCLUSIONS: The bond strength of luting resin to dentin was affected by Ca(OH)2 dressing. Acid etching treatment could not increase the bond strength. CLINICAL RELEVANCE: Adhesion of the fiber post to the root canal wall may be compromised after Ca(OH)2 dressing. An effective method for complete removal of Ca(OH)2 dressing or increase of bond strength for luting resin needs to be developed. PMID:23686133

Lee, Bor-Shiunn; Lin, Yu-Chen; Chen, Sing-Fu; Chen, Shu-Yu; Chang, Che-Chen

2013-05-18

108

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

SciTech Connect

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

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

2011-10-23

109

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

PubMed Central

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

Lopez-Suevos, Francisco; Dickens, Sabine H.

2008-01-01

110

DETERMINATION OF THORIUM IN VARIOUS AQUEOUS SAMPLES BY ANION EXCHANGE. I. ADSORPTION OF THORIUM ON THE ANION EXCHANGE RESIN IN NITRIC ACID-AL OHOL MIXED SOLUTION IN THE PRESENCE OF PHOSPHATE  

Microsoft Academic Search

Adsorption of thorium on the anion exchanger Dowex l-X8 in various ; nitric acid-ethanol mixed solutions and effects of phosphoric acid and the ; phosphate precipitates of calcium and magnesium were studied. When phosphate is ; present, thorium is strongly adsorbed on the resin in low and high concentrations ; of nitric acid and ethanol, respectively. In general, presence of

Akaishi

1962-01-01

111

Monitoring the kinetics of the ion-exchange resin catalysed esterification of acetic acid with ethanol using near infrared spectroscopy with partial least squares (PLS) model  

Microsoft Academic Search

The esterification of acetic acid with ethanol in the presence of a heterogeneous acid catalyst was monitored by near infrared (NIR) spectroscopy. A strong acid macroporous poly(styrene-co-divinylbenzene) based ion-exchange resin was used as catalyst. The liquid phase esterification was carried out in a stirred batch laboratory reactor at 60°C. Samples taken from the reaction mixture were analysed both by NIR

Jarkko Helminen; Mika Leppämäki; Erkki Paatero; Pentti Minkkinen

1998-01-01

112

Biochemical and Genotoxic Responses of Adult Eel ( Anguilla anguillaL.) to Resin Acids and Pulp Mill Effluent: Laboratory and Field Experiments  

Microsoft Academic Search

The potential of a secondary-treated bleached kraft pulp mill effluent (BKPME) and resin acids (RAs) to induce liver ethoxyresorufin-O-deethylase (EROD) activity and erythrocytic nuclear abnormalities (ENAs) in adultAnguilla anguillaL. was investigated in laboratory and field experiments. Hepatic health was assessed by measurement of liver alanine transaminase (ALT). One single intraperitoneal injection of abietic acid (AA) or dehydroabietic acid (DHAA), at

M. Pacheco; M. A. Santos

1999-01-01

113

Basic physical and chemical properties of Reillex{sup TM}-HPQ anion exchange resin and its sorption behavior of halides in aqueous nitric acid solution  

SciTech Connect

The Reillex{sup TM}-HPQ anion exchange resin has a good potential toward the pretreatment of liquid nuclear wastes. In this work, a short procedure was devised to convert 99.997% of the resin from its chloride form to the nitrate form as a foundation of all quantitative measurements. It is determined that the resin can be dried to a constant mass at 60{degree}C in 28 hours and the electrostatic effect during weighings can hence be eliminated. The weight ratio between resins dried at 110{degree}C and 60{degree}C is 0.927{+-}0.005 (one standard deviation). The resin has an apparent pK{sub a} of 3.36{+-}0.05. The sorption capacity from primarily the weakly basic ionogenic sites (RNH{sup +}) is 1.08{+-}0.04 meq/g for resins dried at 60{degree}C. In highly basic solutions, the resin became unstable and started to release a substantial amount of methanol. In nitric acid solutions, the selectivity sequence of halide ions versus nitrate and pertechnetate ions is: TcO{sub 4}{sup -} > I{sup -} > NO{sub 3}{sup -} > Br{sup -} > Cl{sup -} > F{sup -}. The HPQ resin showed no sorption of fluoride ions. Although the sorption of chloride ions is also low the data can be modeled well by an equation similar to the Freundlich isotherm at a pH range between 2.0 and 3.0. Both bromide and iodide ions showed moderate sorptions when [HNO{sub 3}] = 1.00 M and the sorption data can be fitted well to an equation closely related to the Temkin isotherm. 25 refs., 6 figs., 5 tabs.

Wu, Y.Y.J.; Williamson, M.A.; Zhang, Q.; Grissom, M.R.; Chu, I.C. [East Texas State Univ., Commerce, TX (United States)

1996-03-01

114

Acid-breakable-resin-based chemical amplification positive resist for 0.1-um-rule reticle fabrication: design and lithographic performance  

NASA Astrophysics Data System (ADS)

We have designed a new chemical amplification (CA) positive resist for 0.1micrometers reticle fabrication. This positive resist consists of an acid-generator, an acid-diffusion controller, and an acid-breakable (AB) resin that can be converted to initial polyphenol units by an acid-catalyzed reaction. In the exposed region, main-chain scission of the AB resin matrix produces nearly mono-dispersed fragments (the polyphenol). This complete fragmentation results in an extremely high dissolution rate with an aqueous-base developer (tetramethylammonium hydroxide: 2.38 wt%). The AB resin-based resist enabled fabrication of scum free 0.15micrometers line-and-space patterns on a CrOx plate by using a 50-kV electron-beam reticle writer (HL series). The line- edge roughness of patterns delineated by this resist (<10 nm) was less than half that for previously developed novolak-resin-based CA resists (RE series:>30nm).

Migitaka, Sonoko; Arai, Tadashi; Sakamizu, Toshio; Kasuya, Kei; Hashimoto, Michiaki; Shiraishi, Hiroshi

2001-09-01

115

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

PubMed

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

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

2011-01-01

116

Recovery of uranium from phosphoric acid solutions using chelating ion-exchange resins  

Microsoft Academic Search

In fertilizer manufacture, calcium phosphate in phosphate rock is rendered soluble by sulfuric acid attack. The phosphoric acid obtained in this way usually contains 26%--28% PâOâ. Several novel processes have been developed for the recovery of uranium from wet-process phosphoric acid. Experimental measurements have been made on the batch extraction of uranium from phosphoric acid solutions using various chelating ion-exchange

N. Kabay; M. Demircioglu; S. Yayh; E. Guenay; M. Yueksel; M. Saglam; M. Streat

1998-01-01

117

Radiation Synthesis of Poly(Acrylamide-Acrylic Acid-Dimethylaminoethyl Methacrylate) Resin and Its Use for Binding of Some Anionic Dyes  

Microsoft Academic Search

Poly(acrylamide-acrylic acid-dimethylaminoethyl methacrylate) P(AAm-AA-DMAEMA) resin was prepared by the template copolymerization.\\u000a PAAm was used as a template for the copolymerization of DMAEMA and AA in aqueous solution using gamma rays. The adsorption\\u000a of indigo carmine and eriochrome black-T anionic dyes from aqueous media on P(AAm-AA-DMAEMA) has been investigated. The adsorption\\u000a behavior of this resin has been studied under different adsorption

H. M. Abdel-Aziz; T. Siyam

2011-01-01

118

ON THE CHEMICAL CONSTITUTION OF A LIGNITIC RESIN (thesis)  

Microsoft Academic Search

A sink-float procedure, employing a mixture of nheptane and CClâ ; as tbe separation medium, is a satisfactory means of separating the resins from ; the coal in a pure form. These resins are primarily resin acids and esters. The ; resin acids are composed of two major fractions, amber and a form of oxidized ; abietic acid. The oxidized

Tietjen

1958-01-01

119

Aromatic polyoxyalkylene amidoamines as curatives for epoxy resins — derivatives from t-butyl isophthalic acid  

Microsoft Academic Search

The condensation products of alkyl-substituted aromatic dicarboxylic acid and polyoxyalkylene polyamines were synthesized and used as epoxy curing agents. The novel amidoamines, prepared from t-butyl isophthalic acid (t-BuIPA) and polyoxyethylene diamines such as Jeffamine(R) EDR-148 and 192, exhibited fast cnring and good flexibility. Comparisons with other amidoamines derived from isophthalic and Dimer acid, and amines including Jeffamine(R) D-230, were made.

Jiang-Jen Lin; G. P. Speranza; H. G. Waddill

1996-01-01

120

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

2012-06-28

121

Kinetics Characterization of Ions Release Under Dynamic and Batch Conditions. Strong Acid and Strong Base Type Ion Exchange Resins  

Microsoft Academic Search

The purpose of this study has been to investigate the influence of key parameters (i.e., the structure of the resin organic polymer and its particle size, as well as the temperature of the process) on the release of calcium and fluoride ions from cationic and anionic ion exchange resins of strong character, in order to develop a formulation for a

A. Torrado; M. Valiente

2008-01-01

122

Fractionation and utilization of gossypol resin  

SciTech Connect

Gossypol resin is formed as a secondary waste product during distillation of fatty acides isolated from cottonseed oil soap stocks; it is insoluble in water but soluble in products of petroleum distillation. For fractionation, gossypol resin was saponified with caustic soda or caustic potash. Using this method, the resin was separated into unsaponifiable (21-24%) and saponifiable (76-79%) parts. Details of the individual fractions of gossypol resin are presented. The unsaponifiable fraction contains hydrocarbons, alcohols, beta-sito-sterol, beta-amyrin, and vitamin E. The fatty acid fraction of the resin is a mixture of fatty acids and lactones.

Tursunov, A.K.; Dzhailov, A.T.; Fatkhullaev, E.; Sadykov, A.A.

1985-10-01

123

The ion chromatographic separation of high valence metal cations using a neutral polystyrene resin dynamically modified with dipicolinic acid.  

PubMed

A neutral polystyrene resin column, dynamically loaded with dipicolinic acid at a concentration of 0.1 mM in 1 M potassium nitrate eluent, was investigated for the separation characteristics of a number of high valence metal cations over the pH range 0-3. The metal species studied were Th(IV), U(VI), Zr(IV), Hf(IV), Ti(IV), Sn(IV), V(IV) and V(V), Fe(III) and Bi(III), of which Ti(IV), Sn(IV), V(IV) and Fe(III) did not show any retention. For the remaining metal ions, significant retention was obtained with good peak shapes, except for Th(IV), which moved only slightly from the solvent front with some tailing. The retention order at pH 0.3 was Th(IV) < V(V) < Bi(III) < U(VI) < Hf(IV) < Zr(IV). A notable feature of this separation system was the high selectivity shown for uranium, zirconium and hafnium, the last two being nearly resolved in 15 min on the relatively short 10 cm column. PMID:11219043

Cowan, J; Shaw, M J; Achterberg, E P; Jones, P; Nesterenko, P N

2000-12-01

124

Transesterification of cyclohexyl acrylate with n-butanol and 2-ethylhexanol: acid-treated clay, ion exchange resins and tetrabutyl titanate as catalysts  

Microsoft Academic Search

Transesterification of cyclohexyl acrylate with n-butanol and 2-ethylhexanol was studied in a batch reactor using an acid-treated clay, ion exchange resins and tetrabutyl titanate as catalysts. The effect of various parameters on the conversion of cyclohexyl acrylate and towards the selectivity of cyclohexanol were studied to optimise the reaction conditions. The transesterified esters (n-butyl acrylate and 2-ethylhexyl acrylate) were separated

Basudeb Saha; Michael Streat

1999-01-01

125

Low-Density-Plastic-Foam Capsule of Resorcinol\\/Formalin and (Phloroglucinolcarboxylic Acid)\\/Formalin Resins for Fast-Ignition Realization Experiment (FIREX) in Laser Fusion Research  

Microsoft Academic Search

In this report, we describe fuel (deuterium and tritium) capsule preparation for the fast-ignition realization experiment (FIREX) in laser fusion research. The required diameter and thickness of the capsule are 500 and 20 mum, respectively. The material should be plastics with low-density foam. We have prepared such a capsule using (1) a new material of (phloroglucinolcarboxylic acid)\\/formalin resin to control

Fuyumi Ito; Keiji Nagai; Mitsuo Nakai; Takayoshi Norimatsu; Andrei Nikitenko; Sergei Tolokonnikov; Elena Koresheva; Takeshi Fujimura; Hiroshi Azechi; Kunioki Mima

2006-01-01

126

Selective Removal of Zinc from an Electroless Nickel Plating Bath by Solvent Impregnated Resin Using 2-Ethylhexylphosphonic Acid Mono2-Ethylhexyl Ester as the Extractant  

Microsoft Academic Search

A solvent impregnated resin (SIR) containing 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPNA) as the extractant was tested for zinc removal from aqueous solutions, including the real electroless nickel plating bath employed for an aluminum alloy substrate, in order to extend the bath life. The SIR effectively and selectively adsorbed zinc over nickel without any pH adjustment from the plating bath, although

Chaitanya Raj Adhikari; Hideaki Kumano; Mikiya Tanaka

2011-01-01

127

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

128

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

129

Synthesis and rheological properties of poly(methyl methacrylate)\\/polymethacrylic acid nanocomposites as denture resins  

Microsoft Academic Search

Hybrid materials, which consist of organic–inorganic materials, are of profound interest owing to their unexpected synergistically derived properties. Aluminium oxide (Al2O3) nanoparticles\\/polymer composites have been produced using a one-system polymer synthesis. The linear polymer, poly(methyl methacrylate) (PMMA, MW=15,000g\\/mol) and polymethacrylic acid (PMAA) are applied for the stabilization of Al2O3 nanoparticles. The Fourier transfer infrared (FT-IR) analysis data and scanning electron

Mohammad Reza Saboktakin; Roya M. Tabatabaie; Abel Maharramov; Mohammad Ali Ramazanov

2011-01-01

130

Acid–base properties of ion exchangers. I. Optimising of potentiometric titration of ion exchangers exemplified by carboxylic acid resins  

Microsoft Academic Search

The aim of this work was to determined conditions for fast titration the ion exchanger in the one-sample experiment allowing obtaining its equilibrium titration curve. Carboxylic acid ion exchangers KB-4 and Dowex MAC-3 were taken as examples. They were titrated under different conditions with NaOH, KOH and Ba(OH)2. The forward and backward titration of concentrated immersions of finely ground ion

V. S Soldatov; Z. I Sosinovich; T. A Korshunova; T. V Mironova

2004-01-01

131

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

2005-11-02

132

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

2013-06-23

133

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

PubMed Central

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

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

2013-01-01

134

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

National Technical Information Service (NTIS)

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

F. M. Pennebaker K. Adu-Wusu

2010-01-01

135

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

PubMed

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

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

2007-08-01

136

RESIN ATTRITION  

Microsoft Academic Search

ABS>Uranium metal is produced by the bomb reduction of UFâ with Mg. ; The slag from this reduction contains appreciable quantities of U, either in the ; metallic or the tetrafluoride form, in addition to the MgFâ. A process for ; recovering low enrichmeat U from this slag has gone into operation. A study of ; the causes of resin

G. R. Seiler; P. R. Ammann; A. B. Newey

1958-01-01

137

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

SciTech Connect

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

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

1994-10-01

138

[Adhesion of restorative resin to tooth substance. Treatment of tooth surface with aqueous solution of amino-acid derivatives and HEMA].  

PubMed

Although many studies have been made on the reinforcement of the bond between tooth and restorative resin, satisfactory results have not been obtained clinically. Attempts were made to obtain such a reinforced bonding using the aqueous solution of derivatives of amino acid, either N-methacryloyl alanine (MAL) or N-acryloyl alanine (AAL), and 2-hydroxyethyl methacrylate (HEMA). Following the treatment with these surfactants, a tensile bond strength of 103 kgf/cm2 (to enamel) and 80 kgf/cm2 (to dentin) was obtained by MAL-HEMA solution, and that of 99 kgf/cm2 (to enamel) and 58 kgf/cm2 (to dentin) in the case of AAL-HEMA solution. This is considered as the result of either the etching effect of the amino acid derivatives, effect of its reactive products with hydroxyapaptite or reaction between HEMA and an organic component of tooth structure, like a collagen. PMID:2134814

Takahashi, M; Suzuki, K; Nakai, H

1990-01-01

139

Solvent impregnated resins for the recovery of gold from Gold(I)Thiourea solutions  

Microsoft Academic Search

Solvent Impregnated Resins (SIRs) are high surface area, macroporous, polymeric resins which have been physically impregnated with an organic solvent. In this research, three resins have been impregnated with Di-2-ethylhexyl phosphoric acid, a solvent which has shown selectivity to gold. The ability of the resins to recover gold (1) thiourea perchlorate from solution has been investigated. The resins have been

Fiona Fitzpatrick

1997-01-01

140

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.

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

2011-01-01

141

Resin Chemistry  

Microsoft Academic Search

\\u000a During the ensuing years since the last phenolic resins book was published, many new and remarkable developments have occurred\\u000a in the realm of phenolic chemistry and are given in this chapter.\\u000a \\u000a \\u000a A critical examination of the first step or addition step (methylolation) in the preparation of resoles is described and how\\u000a it can be controlled and compared with the typical

Louis Pilato

2010-01-01

142

Enhanced catalysis of Yarrowia lipolytica lipase LIP2 immobilized on macroporous resin and its application in enrichment of polyunsaturated fatty acids.  

PubMed

An immobilization strategy was employed to improve activity and operational stability of Yarrowia lipolytica lipase LIP2 (YlLIP2) by using macroporous resins as carrier. D152H, a cation-exchange resin, was the best support. Under the optimized conditions, the immobilization efficiency was 89.81% and the specific activity was 809,751 U/g, being 2.1-fold higher than that of the free lipase. Bioimprinting and interfacial activation were used to further boost the catalytic activity of YlLIP2, respectively enhanced 21.5-fold, 231.2% and 107.2% compared to the free, non-bioimprinted and non-interfacial-activated lipases. The immobilized lipase exhibited much better thermal and pH stability and broader substrate specificity; when used to enrich docosahexaenoic acid (DHA) from Chlorella protothecoides oil, it could increase 1.66-fold of DHA content and show good operational stability. These indicate that the immobilized YlLIP2 offers a promising approach for the enrichment of DHA. PMID:23347925

Yan, Yunjun; Zhang, Xiaoyan; Chen, Dawei

2012-12-20

143

Modeling of breakthrough curves of single and quaternary mixtures of ethanol, glucose, glycerol and acetic acid adsorption onto a microporous hyper-cross-linked resin.  

PubMed

The adsorption of quaternary mixtures of ethanol/glycerol/glucose/acetic acid onto a microporous hyper-cross-linked resin HD-01 was studied in fixed beds. A mass transport model based on film solid linear driving force and the competitive Langmuir isotherm equation for the equilibrium relationship was used to develop theoretical fixed bed breakthrough curves. It was observed that the outlet concentration of glucose and glycerol exceeded the inlet concentration (c/c0>1), which is an evidence of competitive adsorption. This phenomenon can be explained by the displacement of glucose and glycerol by ethanol molecules, owing to more intensive interactions with the resin surface. The model proposed was validated using experimental data and can be capable of foresee reasonably the breakthrough curve of specific component under different operating conditions. The results show that HD-01 is a promising adsorbent for recovery of ethanol from the fermentation broth due to its large capacity, high selectivity, and rapid adsorption rate. PMID:23819972

Zhou, Jingwei; Wu, Jinglan; Liu, Yanan; Zou, Fengxia; Wu, Jian; Li, Kechun; Chen, Yong; Xie, Jingjing; Ying, Hanjie

2013-06-13

144

Resin composite restorative materials.  

PubMed

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

Ilie, N; Hickel, R

2011-06-01

145

Phenolic Resin Syntactic Foams.  

National Technical Information Service (NTIS)

Syntactic foams were prepared from blends of six phenolic resins and carbon microbubbles. The compressive strength of the phenolic resin foams is equivalent to the strength of foams made from a polyimide resin. Ammonia evolved during the cure diffuses rap...

H. M. McIlroy

1980-01-01

146

Variability and determinants of wood dust and resin acid exposure during wood pellet production: measurement strategies and bias in assessing exposure-response relationships.  

PubMed

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 production plants located in Sweden. Results were used to estimate within- and between-worker variability and to identify uniformly exposed groups and determinants of exposure. In addition, overexposure, whether the risk of the long-term mean exposure of a randomly selected worker exceeding the occupational exposure limit is acceptably low, was calculated as well as the underestimation of the exposure-response relationship (attenuation). Greater variability in exposure between work shifts than between workers was observed with the within-worker variation accounting for 57-99% of the total variance in the individual-based model. Several uniformly exposed groups were detected but were mostly associated with a between-worker variation of zero which is an underestimation of the between-worker variation but an indication of uniformly exposed groups. Cleaning was identified as a work task that increases exposure slightly; so reducing workers' exposure during this operation is advisable. The levels of wood dust were high and were found to pose unacceptable risks of overexposure at all plants for inhalable dust and at three out of four plants for total dust. These findings show that exposure to dust needs to be reduced in this industry. For resin acids, the exposure was classed as acceptable at all plants. According to an individual-based model constructed from the data, the level of attenuation was high, and thus there would be substantial bias in derived dose-response relationships. PMID:18703543

Hagström, Katja; Lundholm, Cecilia; Eriksson, Kare; Liljelind, Ingrid

2008-08-14

147

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

Microsoft Academic Search

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

M. CHANDA; G. L. REMPEL

2000-01-01

148

Separation of transition metals on a poly-iminodiacetic acid grafted polymeric resin column with post-column reaction detection utilising a paired emitter-detector diode system.  

PubMed

The selectivity, retention and separation of transition metals on a short (2 mm x 50 mm) column packed with a poly-iminodiacetic acid functionalised polymer 10 microm resin (Dionex ProPac IMAC-10) are presented. This stationary phase, typically used for the separation of proteins, is composed of long chain poly-iminodiacetic acid groups grafted to a hydrophilic layer surrounding a 10 microm polymeric bead. Through the use of a combination of a multi-step pH and picolinic acid gradient, the separation of magnesium, iron, cobalt, cadmium, zinc, lead and copper was possible, followed by post-column reaction with 4-(2-pyridylazo) resorcinol (PAR) and absorbance detection at 510 nm using a novel and inexpensive optical detector, comprised of two light emitting diodes with one acting as a light source and the other as a detector. Column efficiency for selective transition metals was in excess of N=10,000, with the baseline separation of seven metal cations in <3 min possible under optimised conditions. Detection limits of between 5 and 81 microg/L were possible based upon a 50 microL injection volume. PMID:18778827

Barron, Leon; O'Toole, Martina; Diamond, Dermot; Nesterenko, Pavel N; Paull, Brett

2008-08-19

149

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

150

Novel silica-based ion exchange resin  

SciTech Connect

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

NONE

1997-11-01

151

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

1998-06-01

152

Engineering Plastics from Lignin. IX. Phenolic Resin Synthesis and Characterization  

Microsoft Academic Search

The performance of phenol-formaldehyde (PF) resins, formulated with lignin derivatives previously synthesized as phenolic resin prepolymers, was evaluated by thermal analysis of the curing process, and by a hard maple shear block test. At 54 and 60% phenol replacement levels, respectively, kraft (KL) and steam explosion lignin (SEL)-based resoles exhibited cure behavior very similar to a standard PF resin. Acid

Peter C. Muller; Stephen S. Kelley; Wolfgang G. Glasser

1984-01-01

153

Examination of styrene-divinylbenzene ion-exchange resins, used in contact with food, for potential migrants  

Microsoft Academic Search

The nature of extractable substances from five types of styrene-divinylbenzene ion-exchange resins used in the preparation of foodstuffs was investigated. Strong acid cation resins, strong and weak base anion resins, and an active carbon replacement resin were examined. These resins are used for a variety of purposes including water softening, decalcification of sugar syrups, demineralization, removal of nitrate ions from

J. A. Sidwell; B. G. Willoughby

2006-01-01

154

BASIC PHYSICAL AND CHEMICAL PROPERTIES OF REILLEX-HPQ ANION EXCHANGE RESIN AND ITS SORPTION BEHAVIOR OF HALIDES IN AQUEOUS NITRIC ACID SOLUTION  

Microsoft Academic Search

The Reillex™-HPQ anion exchange resin has a good potential toward the pretreatment of liquid nuclear wastes. In this work, a short procedure was devised to convert 99.997% of the resin from its chloride form to the nitrate form as a foundation of all quantitative measurements. It is determined that the resin can be dried to a constant mass at 60°C

Yen-Yuan J. Wu; Michelle A. Williamson; Qihui Zhang; Melissa R. Grissom; I-Ching Chu

1996-01-01

155

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.

2008-01-01

156

The energy-saving production of tartaric acid using ion exchange resin-filling bipolar membrane electrodialysis  

Microsoft Academic Search

In view of some inherent disadvantages of traditional technique, production of tartaric acid was attempted through the laboratory-scale bipolar membrane electrodialysis (BMED) in this work. Due to the relatively low solubility of bitartrate, the three-compartment configuration but not the two-compartment configuration which is preferred for weak acid production was selected. Thus, one of the aims of this work lies in

Kai Zhang; Meng Wang; Duo Wang; Congjie Gao

2009-01-01

157

Diphonix® Resin: A Review of Its Properties and Applications  

Microsoft Academic Search

The recently developed Diphonix® resin is a new multifunctional chelating ion exchange resin containing geminally 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

R. Chiariza; E. P. Horwitz; S. D. Alexandrators; M. J. Gula

1997-01-01

158

Novel silica-based ion exchange resin  

SciTech Connect

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

Gula, M.; Harvey, J.

1996-12-31

159

THE APPLICATION OF LIQUID ION-EXCHANGE RESINS IN ANALYSIS. PART II. THE REACTIONS OF ZIRCONIUM, TITANIUM AND VANADIUM IN SULPHURIC ACID MEDIA  

Microsoft Academic Search

S> With the advent of liquid ion-exchange resins which are insoluble in ; water but soluble in organic solvents, it is now possible to remove ions from ; solutions by solvent extraction techniques using ion exchange. In Part I, the ; results were given of an investigation into the degree of extraction obtained ; with a liquid anion-exchange resin in

1962-01-01

160

Characterization and utilization in phenolic resins of lignin from wood saccharification by mineral acids. Annual report, October 1, 1984-September 30, 1985  

SciTech Connect

This research is to explore conditions under which the lignin-rich residue from TVA's two stage hardwood based wood saccharification pilot plant can be used as a prepolymer for phenol-formaldehyde resin products and other thermosetting plastics. Six specific tasks studied were to isolate a uniform polymer fraction from the lignin-rich pilot plant residue; to characterize the chemical and molecular structure of the useful lignin fraction; to test the reactivity of this fraction with phenol, with formaldehyde and phenol in sequence, and with propylene oxide, and to analyze the reaction products; to synthesize phenolic resins with substitution levels in excess of 50% of phenol, and to evaluate these resins by thermal analysis; to test selected resins by shear block testing and to prepare polyurethane thermosets by crosslinking with diisocyanates; and to compare the performance of the phenolic resins and polyurethanes with those obtained with other lignins. 4 figs., 3 tabs.

Glasser, W.G.

1985-01-01

161

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

NASA Astrophysics Data System (ADS)

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

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

1997-07-01

162

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

Microsoft Academic Search

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

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

1997-01-01

163

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

164

Resin glycosides from the leaves and stems of Ipomoea digitata  

Microsoft Academic Search

Alkaline hydrolysis of the ether-soluble resin glycoside (jalapin) fraction of the leaves and stems of Ipomoea digitata L. (Convolvulaceae) gave six organic acids, isobutyric, (S)-2-methylbutyric, tiglic, n-decanoic, n-dodecanoic, and cinnamic acids, and two glycosidic acids, quamoclinic acid A and operculinic acid A. Further, a new genuine\\u000a resin glycoside, named digitatajalapin I, was isolated from the jalapin fraction, along with three

Masateru Ono; Hitoshi Fukuda; Hiroko Murata; Kazumoto Miyahara

2009-01-01

165

Phenolic resin syntactic foams  

Microsoft Academic Search

Syntactic foams were prepared from blends of six phenolic resins and carbon microbubbles. The compressive strength of the phenolic resin foams is equivalent to the strength of foams made from a polyimide resin. Ammonia evolved during the cure diffuses rapidly and is not bound by the foam.

McIlroy

1980-01-01

166

Polyester Resin Hazards  

Microsoft Academic Search

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

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

1963-01-01

167

Epoxy resin  

DOEpatents

By mixing one part of a prepolymer containing a polyamine partially polymerized with an organic epoxide and subsequently reacted with a fatty acid containing from 8 to 32 carbon atoms, and then reacting this prepolymer mixture with 3 parts of an organic epoxide, a composition was obtained which made a gas frothable, shear-stable, room temperature curing, low density foam. A particularly advantageous prepolymer was prepared using a polyamine selected from the group consisting of diethylenetriamine, triethylenetetramine, and tetraethylenepentamine, partially polymerized with an organic epoxide having an average molecular weight of about 350 and having an epoxide equivalent of 185 to 192, and reacted with 2-10 weight percent linoleic acid. When one part of this prepolymer was reacted with about three parts of epoxy, and frothed by whipping in air or nitrogen an epoxy foam was produced which could be troweled onto surfaces and into corners or crevices, and subsequently cured, at near ambient temperature, to a strong dimensionally stable foam product.

Wilson, Glenn R. (Dayton, OH); Salyer, Ival O. (Dayton, OH); Ball, III, George L. (West Carrollton, OH)

1976-07-13

168

ELUTION OF URANIUM FROM RESIN  

DOEpatents

A method is described for eluting uranium from anion exchange resins so as to decrease vanadium and iron contamination and permit recycle of the major portion of the eluats after recovery of the uranium. Diminution of vanadium and iron contamination of the major portion of the uranium is accomplished by treating the anion exchange resin, which is saturated with uranium complex by adsorption from a sulfuric acid leach liquor from an ore bearing uranium, vanadium and iron, with one column volume of eluant prepared by passing chlorine into ammonium hydroxide until the chloride content is about 1 N and the pH is about 1. The resin is then eluted with 8 to 9 column volumes of 0.9 N ammonium chloride--0.1 N hydrochloric acid solution. The eluants are collected separately and treated with ammonia to precipitate ammonium diuranate which is filtered therefrom. The uranium salt from the first eluant is contaminated with the major portion of ths vanadium and iron and is reworked, while the uranium recovered from the second eluant is relatively free of the undesirable vanadium and irons. The filtrate from the first eluant portion is discarded. The filtrate from the second eluant portion may be recycled after adding hydrochloric acid to increase the chloride ion concentration and adjust the pH to about 1.

McLEan, D.C.

1959-03-10

169

Cyanate Ester Composite Resins Derived from Renewable Polyphenol Sources.  

National Technical Information Service (NTIS)

Cyanate ester resins were synthesized from a series of renewable phenols including; vanillin, creosol, resorcylic acid, resveratrol, and nordihydroguarietic acid. These phenols can be derived from plant sources and even waste biomass, allowing for high pe...

A. G. Guenthner B. G. Harvey M. Davis M. E. Wright S. Compel

2011-01-01

170

Sorption of organics from aqueous solution onto polymeric resins  

SciTech Connect

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

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

1993-11-01

171

Commercial Ion Exchange Resin Vitrification in Borosilicate Glass  

SciTech Connect

Bench-scale studies were performed to determine the feasibility of vitrification treatment of six resins representative of those used in the commercial nuclear industry. Each resin was successfully immobilized using the same proprietary borosilicate glass formulation. Waste loadings varied from 38 to 70 g of resin/100 g of glass produced depending on the particular resin, with volume reductions of 28 percent to 68 percent. The bench-scale results were used to perform a melter demonstration with one of the resins at the Clemson Environmental Technologies Laboratory (CETL). The resin used was a weakly acidic meth acrylic cation exchange resin. The vitrification process utilized represented a approximately 64 percent volume reduction. Glass characterization, radionuclide retention, offgas analyses, and system compatibility results will be discussed in this paper.

Cicero-Herman, C.A.; Workman, P. [Westinghouse Savannah River Co., Aiken, SC (United States); Poole, K.; Erich, D.; Harden, J. [Clemson Environmental Technologies Laboratory, Anderson, SC (United States)

1998-05-01

172

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

2011-08-26

173

40 CFR Appendix B to Subpart Nnn... - Free Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride  

Code of Federal Regulations, 2010 CFR

...Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride B Appendix B to Subpart...Formaldehyde Analysis of Insulation Resins by Hydroxylamine Hydrochloride 1. Scope This...hydrochloric acid that is liberated when hydroxylamine hydrochloride reacts with...

2009-07-01

174

Improved Well Stimulation With Resin-Coated Proppants  

Microsoft Academic Search

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

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

1983-01-01

175

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

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

1963-01-01

176

Organic-Inorganic Hybrid Materials Based on the Incorporation of Polysilicic Acid Nanoparticle (PN) with Organic Polymers. 3. Shrinkage Characteristics in the Cure of Unsaturated Polyester Resin in the Presence of a Modified PN  

Microsoft Academic Search

The polysilicic acid nanoparticle (PN) was modified by the reaction of silanol group on its surface with silyl group (–Si(OR)3) containing modifiers such as phenyltrimethoxylsilane (PTS), 2-(p-styryl)ethyltrimethoxylsilane (SETS), and 3-(trimethoxylsilyl)propyl methacrylate (TPMA), respectively, to afford modified PNs (M-PNs) including P-PN, S-PN, and T-PN. P-PN, S-PN and T-PN were mixed, respectively, with unsaturated polyester resin (UP) in styrene, UP\\/St, and then

Y. G. Hsu; C. P. Wang

2003-01-01

177

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

178

Cleanup of TMI-2 demineralizer resins  

SciTech Connect

Radiocesium is being removed from Demineralizers A and B (DA and DB by a process that was developed from laboratory tests on small samples of resin from the demineralizers. The process was designed to elute the radiocesium from the demineralizer resins and then to resorb it onto the zeolite ion exchangers contained in the Submerged Demineralizer System (SDS). The process was also required to limit the maximum cesium activities in the resin eluates (SDS feeds) so that the radiation field surrounding the pipelines would not be excessive. The process consists of 17 stages of batch elution. In the initial stage, the resin is contacted with 0.18 M boric acid. Subsequent stages subject the resin to increasing concentrations of sodium in NaH/sub 2/BO/sub 3/-H/sub 3/BO/sub 3/ solution (total B = 0.35 M) and then 1 M sodium hydroxide in the final stages. Results on the performance of the process in the cleanup of the demineralizers at TMI-2 are compared to those obtained from laboratory tests with small samples of the DA and DB resins. To date, 15 stages of batch elution have been completed on the demineralizers at TMI-2 which resulted in the removal of about 750 Ci of radiocesium from DA and about 3300 Ci from DB.

Bond, W.D.; King, L.J.; Knauer, J.B.; Hofstetter, K.J.; Thompson, J.D.

1985-01-01

179

Separation of Sr in combination of ion exchange and Sr resin with alcohol-nitric acid solution and rapid determination of 90 Sr in wine and soil samples  

Microsoft Academic Search

This paper describes the procedures of isolating strontium from wine and soil samples which enable creating of procedure for\\u000a rapid determination of 90Sr. The method of determination of 90Sr includes binding of Sr on the cationic exchanger IR-120 from the sample and simultaneous elution from the cation column\\u000a and binding on the Sr column, separation of Sr on Sr resin

Željko Grahek; Astrid Gojmerac Ivši?; Nikolina Krljan; Marijana Nodilo

180

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

Microsoft Academic Search

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

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

2000-01-01

181

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

182

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

183

Examination of styrene-divinylbenzene ion-exchange resins, used in contact with food, for potential migrants.  

PubMed

The nature of extractable substances from five types of styrene-divinylbenzene ion-exchange resins used in the preparation of foodstuffs was investigated. Strong acid cation resins, strong and weak base anion resins, and an active carbon replacement resin were examined. These resins are used for a variety of purposes including water softening, decalcification of sugar syrups, demineralization, removal of nitrate ions from water and decolourization. Analysis was carried out using electrospray LC-MS- and GC-MS-based methodologies. Extractable substances from new resins were identified as mainly being by-products of the resin manufacturing process. Levels of extractable substances decreased with washing. PMID:16751150

Sidwell, J A; Willoughby, B G

2006-07-01

184

Resin glycosides from the aerial parts of Operculina turpethum.  

PubMed

Three glycosidic acids, turpethic acids A-C, and two intact resin glycosides, turpethosides A and B, all having a common pentasaccharide moiety and 12-hydroxy fatty acid aglycones of different chain lengths, were obtained from the aerial parts of Operculina turpethum. Their structures were elucidated by spectroscopic analyses and chemical correlations. The aglycones were characterized as 12-hydroxypentadecanoic acid in two compounds, 12-hydroxyhexadecanoic acid in two other components, and 12-hydroxyheptadecanoic acid in the fifth compound, which were all confirmed by synthesis. The absolute configurations of these aglycones were all established as S by Mosher's method. These compounds represent the first examples of resin glycosides with a monohydroxylated 12-hydroxy fatty acid as an aglycone, and one compound is the first described resin glycoside having a hydroxylated C(17) fatty acid as its aglycone. PMID:22717506

Ding, Wenbing; Jiang, Zi-Hua; Wu, Ping; Xu, Liangxiong; Wei, Xiaoyi

2012-06-18

185

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.

Mousavinasab, Sayed Mostafa

2011-01-01

186

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

187

Evaluation of a new, macroporous polyvinylpyridine resin for processing 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 greatly stability to chemical and radiolytic degradation. 8 refs., 14 figs.

Marsh, S.F.

1989-04-01

188

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

Microsoft Academic Search

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

Mathew Obichukwu EDOGA

189

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

National Technical Information Service (NTIS)

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

R. A. Orwoll Y. Hu

2002-01-01

190

Flow-injection flame atomic absorption spectrometric determination of trace amounts of cadmium in solid and semisolid milk products coupling a continuous ultrasound-assisted extraction system with the online preconcentration on a chelating aminomethylphosphoric acid resin.  

PubMed

A new sensitive and low-cost method that combines continuous acid extraction, online preconcentration, and flame atomic absorption spectrometry for cadmium determination at microg levels in solid and semisolid milk products is described. A continuous ultrasound-assisted extraction system is used to carry out the dynamic acid extraction step. The acid extract is preconcentrated online on a minicolumn packed with a chelating resin (Chelite P, with aminomethylphosphoric acid groups), and the retained cadmium is eluted with hydrochloric acid and continuously monitored by flame atomic absorption spectrometry. An experimental design (Plackett-Burman 2-6*3/16) is used to optimize the continuous extraction and the preconcentration step. The method allowed a total sampling frequency of 28 samples/h. A good precision of the whole procedure (3.0% relative standard deviation) for a cheese sample containing 0.103 +/- 0.004 microg/g Cd (dry mass), a high enrichment factor (20.5), and detection and quantification limits of 0.014 and 0.067 microg/g, respectively, for a 60 mg of sample were obtained with this methodology. The method was successfully applied to the determination of trace amounts of cadmium in solid and semisolid milk products, such as cheese and yogurt samples. PMID:16512246

Cancela, Sheila; Yebra, M Carmen

191

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method  

Code of Federal Regulations, 2010 CFR

...Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method A Appendix...Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method 1. Scope ...hydrochloric acid that is liberated when hydroxylamine hydrochloride reacts with...

2010-07-01

192

40 CFR Appendix A to Subpart Ddd... - Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method  

Code of Federal Regulations, 2010 CFR

...Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method A Appendix...Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method 1. Scope ...hydrochloric acid that is liberated when hydroxylamine hydrochloride reacts with...

2009-07-01

193

Dilatometry on Thermoset Resins.  

National Technical Information Service (NTIS)

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

A. W. Snow J. P. Armistead

1991-01-01

194

Thermally Stable Laminating Resins.  

National Technical Information Service (NTIS)

Improved thermally stable laminating resins were developed based on the addition-type pyrolytic polymerization. Detailed monomer and polymer synthesis and characterization studies identified formulations which facilitate press molding processing and autoc...

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

1972-01-01

195

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

196

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

2012-08-10

197

Preparation of Magnetic Amine Resins by Polymer Modification  

Microsoft Academic Search

Weak acid ion exchangers prepared by graft polymerization of acrylic acid on cross-linked PVA microbeads containing magnetic iron oxide were converted to strong or weak base resins by reaction with glycidyltrimethylammonium chloride or with epichlorohydrin and diethylamine, respectively. Capacities up to 2.6 meq\\/g were obtained, but the products were susceptible to alkaline hydrolysis. Comparable resins prepared by grafting substituted methacrylic

R. J. Eldridge

1982-01-01

198

Novel strontium-selective extraction chromatographic resin  

SciTech Connect

The effect of nitric acid concentration on the selectivity of a novel extraction chromatographic resin consisting of an octanol solution of 4,4`(5`)-bis(t-butyl-cyclohexano)-18-crown-6 sorbed on an inert polymeric support for strontium over a number of alkali, alkaline earth, and other metal cations was evaluated. The effect of macro quantities of selected elements on strontium retention by the resin was also examined. The resin is shown to exhibit excellent selectivity for strontium over nearly all of the test elements; only lead and tetravalent neptunium, polonium, and plutonium show significant affinity for the material. In addition, concentrations of calcium or sodium ion up to approx.0.1 M are shown not to diminish the sorption of strontium appreciably. Several useful radiochemical separation schemes devised on the basis of the results obtained are described. 35 refs., 6 figs., 3 tabs.

Horwitz, E.P.; Chiarizia, R.; Dietz, M.L. [Argonne National Lab., IL (United States)

1992-04-01

199

Easy flat embedding of oriented samples in hydrophilic resin (LR White) under controlled atmosphere: application allowing both nucleic acid hybridizations (CARD-FISH) and ultrastructural observations.  

PubMed

Hydrophilic resins present the advantage of making possible both hybridization experiments involving either antibodies or oligonucleotide probes and ultrastructural observations. Whereas various embedding protocols are available, only very few concern flat-embedded preparations. In this study we describe an easy protocol for flat embedding of small-oriented biological samples in hydrophilic resins (LR White). The most important constraints are (i) to polymerize the samples under argon-saturated atmosphere (avoiding oxygen which is an inhibitor of LR White polymerization) and (ii) to use transparent flat embedding molds. Two kinds of samples were analyzed: small pieces of large tissue that need to be accurately oriented for a valuable analysis and very small organisms such as free-living nematodes, which are very hard to investigate with conventional paraffin wax embedding techniques. Semi-thin sections strongly reinforce the quality of the observations from oligonucleotidic in situ hybridization experiments by reducing the background usually encountered in oligonucleotide probe hybridization experiments from sections. Such protocols could also permit a cheap alternative to the use of laser scanning confocal microscopes for oligonucleotidic in situ hybridization as in FISH and CARD-FISH experiments from histological sections. The interest of this embedding protocol is reinforced by the fact that molecular in situ hybridization experiments and ultrastructural observations from thin sections can be carried out from a single-small individual (<1mm in length) sample. PMID:18187186

Gros, Olivier; Maurin, Leslie C

2008-01-09

200

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

201

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

202

Core\\/Shell Structured PCM Nanocapsules Obtained by Resin Fortified Emulsion Process  

Microsoft Academic Search

Phase change material (PCM, octadecane) nanocapsules were successfully prepared by resin fortified emulsion (RFE) polymerization using the alkali soluble resin (ASR) of poly(ethylene?co?acrylic acid) (EAA) and poly(styrene?co?acrylic acid) (SAA). Stable PCM nanocapsules were obtained by resin fortified emulsion polymerization, which could be attributed to the prevention of Ostwald ripening due to PCM being hydrophobic. Analysis of online FTIR measurements throughout

2007-01-01

203

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

204

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

NASA Astrophysics Data System (ADS)

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

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

2009-07-01

205

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

206

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

207

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

208

Wood Panel Adhesives from Low Molecular Mass Lignin and Tannin without Synthetic Resins  

Microsoft Academic Search

Mixed interior wood panel tannin adhesive formulations were developed in which lignin was in considerable proportion, 50%, of the wood panel binder, and in which no 'fortification' with synthetic resins, such as isocyanates or phenol-formaldehyde resins as used in the past, was necessary to obtain results satisfying relevant standards. A low molecular mass lignin obtained industrially by formic acid\\/acetic acid

P. Navarrete; H. R. Mansouri; A. Pizzi; S. Tapin-Lingua; B. Benjelloun-Mlayah; H. Pasch; S. Rigolet

2010-01-01

209

CTBN Modified Epoxy Resin.  

National Technical Information Service (NTIS)

An encapsulating resin for electronic components is evaluated for critical parameters. The encapsulant studied is a CTBN/Epoxy/DEA system. Several curatives were evaluated for use with the system, as were the effect of an antioxidant. Compared with a more...

K. E. Creed

1975-01-01

210

Resin composite contours.  

PubMed

When placing posterior composite resin restorations, clinicians often struggle to achieve good contacts. Frequently contacts that are successful are only confined to the occlusal aspect of the proximal wall. A clinical technique is discussed which achieves the correct contour as well as tight contacts. The technique is also minimally invasive and highly aesthetic. PMID:20448605

Sidelsky, H

2010-05-01

211

Preirradiation grafting of ethylene vinyl acetate copolymer resins  

Microsoft Academic Search

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

B. J Ringrose; E Kronfli

1999-01-01

212

A NOVEL STRONTIUM-SELECTIVE EXTRACTION CHROMATOGRAPHIC RESIN  

Microsoft Academic Search

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

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

1992-01-01

213

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 standard method for eluting the cesium from the RF resin uses 15-20 bed volumes (BV) of 0.5 M nitric acid (HNO3). 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 generated by the standard elution method exceeds the capacity of DWPF to destroy the nitrate ions and maintain the required chemical reducing conditions in the glass melt. 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 bed volumes of 0.5 M nitric acid 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 standard elution method removes a very small quantity of cesium from the resin. The resin was loaded with 9.5 g Cs/L of resin prior to elution, which is the maximum expected loading for RF resin treating the actual dissolved salt waste at SRS. For the baseline elution method, 465 g of nitrate is used per liter of resin, and >99.9999% of the cesium is removed from the resin. An alternative method that used 4 bed volumes of 0.5 M HNO3 followed by 11 bed volumes of 0.05 M HNO3, used 158 g of nitrate per liter of resin (66% less nitrate than used for the standard elution) and removed >99.998% of the cesium. A staccato flow mode using 0.5 M HNO3 (1 hr on at 1 BV/hr, followed by 3 hrs off) after the resin had been titrated using a continuous flow of acid at 1 BV/hr removed 99.9998% of the cesium while using 12 BV of acid (20% less than the baseline). Formic acid was slightly less efficient than nitric acid for eluting the resin, but 20 BV of 0.5 M HCOOH removed 99.98% of the cesium from the resin.

Taylor, Paul Allen [ORNL; Johnson, Heather Lauren [University of Tennessee, Knoxville (UTK)

2009-01-01

214

ION EXCHANGE RESIN SEPARATION OF CALCIUM AND STRONTIUM  

Microsoft Academic Search

Calcium and Sr were separated on an Amberlite IR-120 resin column with ; ethylenediaminetetraacetic acid, and Ca was determined spectrophotometrically and ; in the presence of ethylenediaminetetraacetic acid. Calcium recovery from the ; CaEDTA complex was 85% at the 100 mu g level. Recoveries of Ca from the CaEDTA ; complex in the presence of large quantities of EDTA were

Breault

1963-01-01

215

Composition of asphaltenes and resins of west Siberian petroleums  

SciTech Connect

ESR and X-ray diffraction analysis was used to examine asphaltene and resin samples of West Siberia. Experiments were carried out to simulate the effect of catagenesis on resin and asphaltene composition. Processes of thermocatalytic transformations of crude oil in the deposit were found to have no marked effect on asphaltene and resin composition. Transformation of the organic input at sedimentation was assumed to be the main factor determining the qualitative and quantitative composition of crude oil resins and asphaltenes of West Siberia. Petroleums formed from organic matter, accumulating under reducing conditions, contain more asphaltenes and resins, they include much tetravalent vanadium and the asphaltenes have abundant paramagnetic centres. Petroleums formed from oxidized organic matter contain very little asphaltene low concentrations of paramagnetic centers, and little tetravalent vanadium. Resins of these petroleums are rich in oxygen. High levels of asphalt-resin matter in petroleums is related to the presence in the initial organic progenitors of polyunsaturated fatty acids and various nitrogen- and sulfur-containing compounds.

Goncharov, I.V.; Babicheva, T.A.; Bodak, A.N.; Nemirovskaya, G.B.; Mashigorov, A.A.

1985-01-01

216

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

217

Decomposition of Rare Earth Loaded Resin Particles  

SciTech Connect

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

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

2010-09-01

218

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

DOEpatents

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

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

1999-01-01

219

Enlightening the past: analytical proof for the use of Pistacia exudates in ancient Egyptian embalming resins.  

PubMed

Mastic, the resinous exudate of the evergreen shrub Pistacia lentiscus, is frequently discussed as one of the ingredients used for embalming in ancient Egypt. We show the identification of mastic in ancient Egyptian embalming resins by an unambiguous assignment of the mastic triterpenoid fingerprint consisting of moronic acid, oleanonic acid, isomasticadienonic and masticadienonic acid through the consolidation of NMR and GC/MS analysis. Differences in the observed triterpenoid fingerprints between mummy specimens suggest that more than one plant species served as the triterpenoid resin source. Analysis of the triterpenoid acids of ancient embalming resin samples in the form of their methyl- and trimethylsilyl esters is compared. In addition we show a simple way to differentiate between residues of mastic from its use as incense during embalming or from direct mastic application in the embalming resin. PMID:22083980

Nicholson, Tim M; Gradl, Manuela; Welte, Beatrix; Metzger, Michael; Pusch, Carsten M; Albert, Klaus

2011-11-14

220

Uptake of metal ions by a new chelating ion exchange resin. Part 8. Simultaneous uptake of cationic and anionic species  

SciTech Connect

The uptake of tri-, tetra-, and hexa-valent actinides as well as pertechnetate anions by some new multifunctional ion exchange resins has been investigated. The new resins, identified as Diphonix A, for anionic Diphonix, contain the same geminally substituted diphosphonic acid groups bonded to a styrenic-based polymer matrix as the regular Diphonix resin, plus strong base anion exchange groups such as the tetralkylammonium (Diphonix A - Type 1 resins) or the quaternized pyridinium (Diphonix A - Type 2 resins) groups. Our uptake measurements have shown that the Type 2 Diphonix A resins are as effective as the regular Diphonix resin in the rapid uptake of actinides from acidic solutions, while at the same time sorbing pertechnetate anions in a manner comparable to existing commercial anion exchange resins. The failure of the Type 1 Diphonix A resins to perform equally well has been explained as a consequence of the mutual interaction of adjacent diphosphonic acid groups and tetralkylammonium groups. Uptake data have also been obtained with Se(IV). The behavior of the Diphonix A resins toward Se(IV) uptake in acidic solutions is comparable to that of commercial anion exchange resins. 21 refs., 9 figs., 3 tabs.

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

1996-05-01

221

System for removing contaminants from plastic resin  

DOEpatents

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

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

2010-11-23

222

Comparison of the effect of storage media on shear punch strength of resin luting cements  

Microsoft Academic Search

ObjectivesTo measure the shear punch strength of eight resin-containing luting cements before and after immersion in acidic solution and ethanol at different temperatures (37°C and 60°C). Method: Specimens were prepared from six resin luting cements; Set (SDI), Panavia F (Kuraray), RelyX Veneer (3M\\/ESPE), VarioloinkII (Ivoclar), Maxcem (Kerr), Nexus2 (Kerr) and two Resin-modified glass-ionomer luting cements (RM-GICs); GC Fuji Plus (GC

Rafat Bagheri; Ay?e Mese; Michael F. Burrow; Martin J. Tyas

2010-01-01

223

Composite Properties of Polyimide Resins Made From ÒSalt-LikeÓ Solution Precursors1  

Microsoft Academic Search

Recent work in high temperature materials at NASA Langley Research Center (LaRCª) have led to the development of new polyimide resin systems with very attractive properties. The majority of the work done with these resin systems has concentrated on determining engineering mechanical properties of composites prepared from a poly(amide acid) precursor. Three NASA Langley-developed polyimide matrix resins, LaRCª-IA, LaRCª-IAX, and

Yoshiaki Echigo; Hisayasu Kaneshiro

224

Effect of Ion Exchange Resins on Composition of Milk and Its Fractions  

Microsoft Academic Search

Ultraeentrifugation and dialysis studies were made to determine the distribution of calcium, phosphorus, and nitrogen in milk treated with ion exchange resins to remove radionuclides. In System I, milk was passed through Dowex 2-X8 (Cl:P:Cit) resin, acidified to pH 5.35 with citric acid, passed through IR-120 (Ca:Mg:K:Na) resin, and neutralized to pH 6.8 with KOH. In System II, the same

G. K. Murthy

1967-01-01

225

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

Microsoft Academic Search

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

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

1998-01-01

226

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

Microsoft Academic Search

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

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

1997-01-01

227

Effects of Resin Hydrophilicity on Dentin Bond Strength  

PubMed Central

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

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

2008-01-01

228

Indirect resin composites  

PubMed Central

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

Nandini, Suresh

2010-01-01

229

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

Microsoft Academic Search

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

Lone-Wen Tai; Paul A. Lessing

1992-01-01

230

Elution and electrowinning of gold from gold-selective strong-base resins  

Microsoft Academic Search

The recovery of gold was investigated using the new gold-selective resin, Minix, which was developed by Mintek. The most suitable elution technique for this resin was found to be an acidic thiourea eluant. The gold-selective adsorption characteristics of Minix, particularly its high selectivity against cobalt and iron cyanides, make it possible to use the advantages of the thiourea method (fast

P. J. Conradie; M. W. Johns; R. J. Fowles

1995-01-01

231

Regeneration of strong-base anion-exchange resins by sequential chemical displacement  

Microsoft Academic Search

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

Gilbert M. Brown; Baohua Gu; Bruce A. Moyer; Peter V. Bonnesen

2002-01-01

232

Comparison of some physicochemical characteristics between solid and fluid Chios mastic resin  

Microsoft Academic Search

A comparative study was done on some physicochemical characteristics of solid and fluid mastic resin, harvested by the traditional and a new method. the parameters measured were: solubility, colour, grain size, specific gravity, hardness, viscosity, essential oil content, ash and fatty acids. Colour, hardness and vicosity were the main characteristics which differ significantly between the two types of resin and

M. Melanitou; D. Papanicolaou; K. Katsaboxakis; K. Stamoula

1995-01-01

233

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

National Technical Information Service (NTIS)

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

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

1981-01-01

234

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

PubMed Central

A new configuration integrated ion exchange effect with both electro-migration and electrochemical reaction in a single cell was developed to effectively retrieve metal ions from simulated wastewater using ion exchange resins without additive chemicals. By simply assembling cation exchange resins and anion exchange resins separated by homogeneous membranes, we found that the system will always be acidic in the concentrate compartment so that ion exchange resins could be in-situ regenerated without hydroxide precipitation. Such a realizable design will be really suitable for wastewater purification.

Chen, Xue-fen; Wu, Zu-cheng

2005-01-01

235

Cytotoxic alkoxylated xanthones from the resin of Garcinia hanburyi.  

PubMed

Three new xanthones, garcinolic acid (1), 10?-ethoxy-9,10-dihydromorellic acid (2), and 10?-ethoxy-9,10-dihydrogambogenic acid (3), along with six known compounds were isolated from the resin of Garcinia hanburyi. These compounds were tested for their cytotoxicities against A549, HCT116, SK-BR-3 and HepG2, and showed high inhibitory effects on the cell lines. PMID:22981505

Deng, Yun-Xia; Pan, Sheng-Li; Zhao, Sheng-Yin; Wu, Meng-Qiang; Sun, Zhong-Qiang; Chen, Xiu-Hua; Shao, Zhi-Yu

2012-09-06

236

ELUTION OF URANIUM FROM RESIN  

Microsoft Academic Search

A method is described for eluting uranium from anion exchange resins so ; as to decrease vanadium and iron contamination and permit recycle of the major ; portion of the eluats after recovery of the uranium. Diminution of vanadium and ; iron contamination of the major portion of the uranium is accomplished by ; treating the anion exchange resin, which

1959-01-01

237

Mechanical Retention of Resin Veneers.  

National Technical Information Service (NTIS)

Mechanical retention of resin veneers is provided for by a number of means, including the use of retentive beads. Studies have been reported in which resin-gold bonds were evaluated using beads, but no known effort had been made to determine the number be...

J. W. O'Hara W. G. Richardson R. J. Leupold G. B. Pelleu

1974-01-01

238

Water Damage in Polyester Resins  

Microsoft Academic Search

The nature of cracks, produced in three cured polyester resins during exposure to water has been studied by the combined techniques of optical microscopy, scanning electron microscopy and electron probe X-ray microanalysis. There are many cracks totally enclosed within the resin and it is shown that these must be attributed to pockets of high pressure produced at impurity inclusions by

K. H. G. Ashbee; F. C. Frank; R. C. Wyatt

1967-01-01

239

Phosphorous-Containing Imide Resins.  

National Technical Information Service (NTIS)

Flame-resistant reinforced bodies are disclosed which are composed of reinforcing fibers, filaments or fabrics in a cured body of bis- and tris-imide resins. These resins are derived from tris(m-aminophenyl) phosphine oxides by reaction with maleic anhydr...

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

1983-01-01

240

Uranium removal from contaminated groundwater by synthetic resins.  

PubMed

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

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

2007-07-14

241

On-resin synthesis of an acylated and fluorescence-labeled cyclic integrin ligand for modification of poly(lactic-co-glycolic acid).  

PubMed

Cyclic Arg-Gly-Asp (RGD) peptides show remarkable affinity and specificity to integrin receptors and mediate important physiological effects in tumor angiogenesis. Additionally, they are one of the keyplayers in improving the biocompatibility of biomaterials. The fully biodegradable polymer poly(lactic-co-glycolic acid) (PLGA) is frequently used for biomedical implants and can be applied as nanoparticles for drug delivery. The aim of this work was the generation of a lipidated c[RGDfK] peptide including a second functionality for coating of hydrophobic PLGA. Therefore, we established a general and straightforward strategy for the introduction of two different modifications into the same c[RGDfK] peptide. This allowed the generation of a palmitoylated integrin-binding lipopeptide that shows high affinity to PLGA. Additionally, we coupled 5(6)-carboxyfluorescein to the second site for modification to enable sensitive quantification of the immobilized lipopeptide on PLGA. In conclusion, we present a synthesis protocol that enables the preparation of c[RGDfK] lipopeptides with a strong affinity to PLGA and an additional site for modifications. This will provide the opportunity to introduce a variety of effector molecules site-specifically to the c[RGDfK] lipopeptide, which will enable the introduction of multifunctionality into c[RGDfK]-coated PLGA devices or nanoparticles. PMID:23161641

Hassert, Rayk; Hoffmeister, Peter-Georg; Pagel, Mareen; Hacker, Michael; Schulz-Siegmund, Michaela; Beck-Sickinger, Annette G

2012-11-01

242

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

Code of Federal Regulations, 2010 CFR

...Manufacture of Amino/Phenolic Resins 2 Table 2...Manufacture of Amino/Phenolic Resins Pt. 63, Subpt...Manufacture of Amino/Phenolic Resins Organic HAP... Cresol and cresylic acid (mixed) 1319-77-3...91-20-3 Yes Yes Phenol 108-95-2...

2010-07-01

243

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

Code of Federal Regulations, 2010 CFR

...Manufacture of Amino/Phenolic Resins 2 Table 2...Manufacture of Amino/Phenolic Resins Pt. 63, Subpt...Manufacture of Amino/Phenolic Resins Organic HAP... Cresol and cresylic acid (mixed) 1319-77-3...91-20-3 Yes Yes Phenol 108-95-2...

2009-07-01

244

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

245

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

NASA Astrophysics Data System (ADS)

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

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

2009-07-01

246

Separation of zirconium and hafnium using Diphonix® chelating ion-exchange resin  

Microsoft Academic Search

The sorption behavior and possible separation of zirconium and hafnium from acid solution was studied on Diphonix® chelating resin containing diphosphonic, sulfonic and carboxylic acid groups. Sulfuric acid solution was selected and then used in dynamic studies. The effects of acid concentration, temperature and solution flow rate on the separation of Zr and Hf using Diphonix® ion-exchanger were investigated. The

M. Smolik; A. Jakóbik-Kolon; M. Pora?ski

2009-01-01

247

The effects of driers on film properties of alkyd resin  

Microsoft Academic Search

Reports on a comprehensive study of the effects of different driers on film properties of alkyd resin. The driers selected for study were calcium naphthanate and the octoates of cobalt, manganese, lead and zirconium. The properties studied were hardness, adhesion, flexibility, film formation, skinning tendency, water and acid resistance, viscosity and drying time. Concludes that driers not only dry coatings

V. D. Athawale; A. V. Chamanker

1997-01-01

248

Grafted methylenediphosphonate ion exchange resins  

DOEpatents

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

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

1997-04-08

249

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

SciTech Connect

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

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

1996-06-01

250

Synthesis of Improved Polyester Resins.  

National Technical Information Service (NTIS)

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 re...

A. H. McLeod C. B. Delano

1979-01-01

251

The leachability of decontamination ion-exchange resins solidified in cement at operating nuclear power plants  

SciTech Connect

Data are presented on the release of radionuclides, stable metals, and organic reagents from decontamination ion-exchange resin wastes solidified in Portland cement. Both solidified and unsolidified decontamination resin waste samples were collected from five commercial light water reactors following chemical decontaminations of primary coolant systems. The decontaminations were performed using the Can-Decon, AP/Citrox, Dow NS-1, and LOMI processes. Samples of unsolidified decontamination resin waste were analyzed for concentrations of 10 CFR Part 61 radionuclides, selected transition metals, and organic chelating and complexing agents. The organic acids included oxalic acid, citric acid, formic acid, picolinic acid, ethylenediaminetetraacetic acid (EDTA), and diethylenetriaminepentaacetic acid (DPTA). Seven solidified resin waste samples were leached in deionized water following the ANS 16.1 leach-test procedure. Releases rates and leachability indexes of radionuclides, transition metals, and organic acids were determined. Analytical methods are described which were used to measure organic acids in resin wastes and in leachate solutions generated during leach-testing of waste form samples. Gas-liquid and ion chromatography methods were developed which allowed detection of organic acids in the tenths-of-a-ppM range. 59 refs., 65 figs., 55 tabs.

McIsaac, C.V.; Mandler, J.W.

1989-03-01

252

Synthetic-resin-free wood panel adhesives from mixed low molecular mass lignin and tannin  

Microsoft Academic Search

Mixed interior wood panel tannin adhesive formulations were developed in which lignin is in considerable proportion, 50%,\\u000a of the wood panel binder and in which no “fortification” with synthetic resins, such as isocyanates and phenol-formaldehyde\\u000a resins as used in the past, was necessary to obtain results satisfying relevant standards. A low molecular mass lignin obtained\\u000a industrially by formic acid\\/acetic acid

H. R. Mansouri; P. Navarrete; A. Pizzi; S. Tapin-Lingua; B. Benjelloun-Mlayah; H. Pasch; S. Rigolet

2011-01-01

253

Resin composition having lubricating properties  

Microsoft Academic Search

This patent describes a resin composition having lubricating properties, which comprises; (i) 100 parts by weight of a synthetic resin, (ii) from 0.5 to 20.0 parts by weight of an organopolysiloxane, and (iii) from 0.5 to 20.0 parts by weight of a fluorine-containing elastomer or from 0.05 to 7.0 parts by weight of an alkoxysilane, wherein at least one of

M. Morozumi; M. Egami

1988-01-01

254

Method for permanently storing radioactive ion exchanger resins  

Microsoft Academic Search

A method is claimed for forming a hardened product containing a radioactive ion exchanger resin in a condition for permanent, noncontaminating storage, by the steps of: providing, before fixing, a mass of such ion exchanger resin saturated in water, the resin being at least one resin selected from the group consisting of spherical resins and powdered resins; mixing the resin

S. Kunze; G. Eden; R. Koster

1984-01-01

255

Tensile strength of enamel-resin-metal joints.  

PubMed

This study evaluated the tensile strength of enamel-resin-metal joints formed with four adhesive systems for attaching resin-bonded FPDs. Groups of 10 cast alloy cylinders were blasted with 50 microns alumina, washed, and prepared for bonding according to the resin as follows: (1) Panavia Ex with no treatment, (2) Super-Bond oxidized for 2 minutes with potassium permanganate in sulphuric acid, (3) Conclude electrolytically etched, and (4) ABC conditioned with primer. The cylinders were bonded to etched human enamel and after 24 hours in water at 37 degrees C the tensile strengths of the joints were recorded. Joint failure was examined under a stereomicoscope and a scanning electron microscope. The results demonstrated that the adhesive system influenced the tensile strength and mode of failure of the joints. PMID:2657026

Aboush, Y E; Jenkins, C B

1989-06-01

256

Removal of phenols from aqueous solution by XAD-4 resin.  

PubMed

The experiments on the adsorption of phenols from aqueous solution by Amberlite XAD-4, a polystyrene-divinylbenzene resin without functional group, were carried out under different conditions. The phenols studied in this research include 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, 2-nitrophenol, 2,4-dinitrophenol, 2-methylphenol, and 2,4-dimethylphenol. The experimental observations indicate that adsorption behavior of various phenols by XAD-4 resin could be described by either Langmuir or Freundlich models. The removals of phenols by XAD-4 resin for solutions of different pH varied significantly and can be explained by the species distribution of phenols in aqueous solutions. Phenols were effectively removed by XAD-4 resin at acidic conditions where the presence of molecular phenol species dominates. The removal decreased sharply for alkaline solutions where the negatively-charged ionic species is the dominant phenol species. The proposed adsorption equilibrium model adequately describes the sorption behavior of phenols by XAD-4 resin. The presence of functional groups on the benzene ring of various phenols plays an important role on the extent of adsorption. The removals of phenols by adsorption were found to correlate with the octanol/water partition coefficients of various phenol compounds. PMID:11080569

Ku, Y; Lee, K C

2000-12-30

257

Cariogenic bacteria degrade dental resin composites and adhesives.  

PubMed

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

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

2013-09-11

258

Dual ambroxal and chlorpheniramine resinate as an alternative carrier in concurrent resinate administration.  

PubMed

Two classical resinates, ambroxal (AMX) resinate and chlorpheniramine (CPM) resinate, and a novel formulation of dual AMX and CPM resinate were prepared by the batch method. The dissolution behavior of the drug from the classical resinates, a mixture of two classical resinates, and the dual-drug resinate in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was examined and compared. The equilibrium of drug on to the resin and the re-exchange of the drug on to the resinate were also investigated. The drug release pattern from the resinate followed the particle diffusion process. The type of dissolution medium affected the amount of drug released from the resinate. The amount of drug released from the dual AMX and CPM resinate was not significantly different from that from the classical AMX resinate or CPM resinate (p < 0.05), but was considerably higher than that from the concurrent administration of two classical resinates (p > 0.05). These results indicated that the concurrent administration of the resinates affected drug release from the resinate, and the dual-drug resinate can be used as an alternative carrier for an ion-exchange delivery system. PMID:12685813

Akkaramongkolporn, P; Ngawhirunpat, T

2003-03-01

259

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

PubMed

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

Torlako?lu, A; Güçlü, G

2008-04-18

260

Identification and quantitative determination of lignans in Cedrus atlantica resins using 13C NMR spectroscopy.  

PubMed

Identification and quantitative determination of individual components of resin collected on the trunk of 28 Cedrus atlantica trees, grown in Corsica, has been carried out using 13C NMR spectroscopy. Eight resin acids bearing either the pimarane or abietane skeleton, two monoterpene hydrocarbons and four oxygenated neutral diterpenes have been identified, as well as three lignans, scarcely found in resins. Three groups could be distinguished within the 28 resin samples. The nine samples of Group I had their composition dominated by diterpene acids (33.7-45.8%), with abietic acid (6.2-18.7%) and isopimaric acid (5.1-12.6%) being the major components. The four samples of Group II contained resin acids (main components) and lignans in moderate amounts (up to 10.3%). Conversely, lignans (38.8-63.8%) were by far the major components of the 15 samples of Group III. Depending on the sample, the major component was pinoresinol (18.1-38.9%), lariciresinol (17.2-33.7%) or lariciresinol 9'-acetate (16.9-29.1%). Finally, due to the high biological interest in lignans, a rapid procedure, based on 1H NMR spectroscopy, was developed for quantification of lignans in resins of C. atlantica. PMID:21485279

Nam, Anne-Marie; Paoli, Mathieu; Castola, Vincent; Casanova, Joseph; Bighelli, Ange

2011-03-01

261

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

262

TGR5 potentiates GLP-1 secretion in response to anionic exchange resins  

PubMed Central

Anionic exchange resins are bona fide cholesterol-lowering agents with glycemia lowering actions in diabetic patients. Potentiation of intestinal GLP-1 secretion has been proposed to contribute to the glycemia lowering effect of these non-systemic drugs. Here, we show that resin exposure enhances GLP-1 secretion and improves glycemic control in diet-induced animal models of “diabesity”, effects which are critically dependent on TGR5, a G protein-coupled receptor that is activated by bile acids. We identified the colon as a major source of GLP-1 secretion after resin treatment. Furthermore, we demonstrate that the boost in GLP-1 release by resins is due to both enhanced TGR5-dependent production of the precursor transcript of GLP-1 as well as to the local enrichment of TGR5 agonists in the colon. Thus, TGR5 represents an essential component in the pathway mediating the enhanced GLP-1 release in response to anionic exchange resins.

Harach, Taoufiq; Pols, Thijs W. H.; Nomura, Mitsunori; Maida, Adriano; Watanabe, Mitsuhiro; Auwerx, Johan; Schoonjans, Kristina

2012-01-01

263

Natural amber, copal resin and colophony investigated by UV-VIS, infrared and Raman spectrum  

NASA Astrophysics Data System (ADS)

Natural amber, copal resin and colophony are have investigated by UV-VIS, infrared and Raman spectrum. In order to distinguish the natural amber, copal resin and colophony, we have successfully used the nondestructive examination (NDE) technology. The results show that UV-VIS could not distinguish these compositions. The infrared spectra can distinguish them, but the technology may destroy the specimen. The Raman spectra show three characteristic peaks of vibration near position 932 cm-1 and position 1179 cm-1 of copal resin, which confirm the existence of terpenes compounds in it. In the Raman spectra of colophony, the vibration characteristic peak at position 1589 cm-1, caused by the conjugate double bond of internal unsaturated resin acid, is the basis of the characteristic difference between colophony and natural amber. The advantages of the distinguished technology by Raman spectroscopy are convenient and nondestructive examination for natural amber, copal resin and colophony.

Rao, ZhiFan; Dong, Kun; Yang, XiaoYun; Lin, JinChang; Cui, XiaoYing; Zhou, RongFeng; Deng, Qing

2013-08-01

264

Phenolic cation exchange resin material for recovery of cesium and strontium  

DOEpatents

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

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

1983-01-01

265

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2010 CFR

...fluoride) resins consist of basic resins produced by the polymerization of...The poly(vinyl fluoride) basic resins have an intrinsic viscosity...technical grade. (2) Solution. Powdered resin and solvent are heated at...

2010-01-01

266

76 FR 4936 - Granular Polytetrafluoroethylene Resin From Italy  

Federal Register 2010, 2011, 2012, 2013

...Granular Polytetrafluoroethylene Resin From Italy AGENCY: United States International Trade...resin (``granular PTFE resin'') from Italy...duty orders on granular PTFE resin from Italy and Japan (75 FR 67082-67083 and...

2011-01-27

267

Synthesis and characterization of new modified anti-corrosive polyesteramide resins incorporated pyromellitimide ring for surface coating  

Microsoft Academic Search

In this paper new modified anti-corrosive polyesteramide resins were obtained by means of a condensation polymerization reaction between N,N-bis (2-hydroxyethyl) linseed oil fatty acid amide (HELA) and phthalic anhydride (PA), which was partially replaced with pyromellitimide acetic acid (PAA) as a new dibasic acid source. The structure of the resin was confirmed by FT-IR and 1H NMR spectral studies. The

H. Abd El-Wahab; M. Abd EL-Fattah; M. B. M. Ghazy

2011-01-01

268

Epoxy Resins in Electron Microscopy  

PubMed Central

A method of embedding biological specimens in araldite 502 (Ciba) has been developed for materials available in the United States. Araldite-embedded tissues are suitable for electron microscopy, but the cutting qualities of the resin necessitates more than routine attention during microtomy. The rather high viscosity of araldite 502 also seems to be an unnecessary handicap. The less viscous epoxy epon 812 (Shell) produces specimens with improved cutting qualities, and has several features—low shrinkage and absence of specimen damage during cure, minimal compression of sections, relative absence of electron beam-induced section damage, etc.—which recommends it as a routine embedding material. The hardness of the cured resin can be easily adjusted by several methods to suit the materials embedded in it. Several problems and advantages of working with sections of epoxy resins are also discussed.

Finck, Henry

1960-01-01

269

Effect of Non-halogen Flame Retardant Additives on the Properties of Vinyl Ester Resins and their Composites  

Microsoft Academic Search

The paper describes the effect of combination of char forming additives and char forming catalysts on limiting oxygen index (LOI), smoke density and mechanical properties of neat as well as glass fibre reinforced vinyl ester (VE) resins. Three different samples of VE resins were prepared by reacting diglycidyl ether of bisphenol-A and methacrylic acid in stoichiometric (1: 2, sample A)

Mona Malik; Veena Choudhary; I. K. Varma

2002-01-01

270

MODELING ION-EXCHANGE PROCESSING WITH SPHERICAL RESINS FOR CESIUM REMOVAL  

SciTech Connect

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

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

2012-09-19

271

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2010 CFR

...polymerization of Nylon 66 salts and epsilon -caprolactam. (5) Nylon 11 resins are manufactured...by the polymerization of epsilon- caprolactam. (7) Nylon 66T resins are manufactured...to 1 ratio by weight of epsilon -caprolactam and omega -laurolactam....

2009-04-01

272

21 CFR 177.1500 - Nylon resins.  

Code of Federal Regulations, 2010 CFR

...polymerization of Nylon 66 salts and epsilon -caprolactam. (5) Nylon 11 resins are manufactured...by the polymerization of epsilon- caprolactam. (7) Nylon 66T resins are manufactured...to 1 ratio by weight of epsilon -caprolactam and omega -laurolactam....

2010-01-01

273

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 CFR

...Specifications. Polyestercarbonate resins identified in paragraph (a) of this section can be identified by their characteristic infrared spectrum. The resins shall comply with either or both of the following specifications: (i) The solution...

2009-04-01

274

21 CFR 177.1580 - Polycarbonate resins.  

Code of Federal Regulations, 2010 CFR

...c)(2) of this section. (1) Specification. Polycarbonate resins can be identified by their characteristic infrared spectrum. (2) Extractives limitations. The polycarbonate resins to be tested shall be ground or cut...

2009-04-01

275

21 CFR 177.1580 - Polycarbonate resins.  

Code of Federal Regulations, 2010 CFR

...c)(2) of this section. (1) Specification. Polycarbonate resins can be identified by their characteristic infrared spectrum. (2) Extractives limitations. The polycarbonate resins to be tested shall be ground or cut...

2010-01-01

276

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2010 CFR

...Specifications. Polyestercarbonate resins identified in paragraph (a) of this section can be identified by their characteristic infrared spectrum. The resins shall comply with either or both of the following specifications: (i) The solution...

2010-01-01

277

21 CFR 177.1580 - Polycarbonate resins.  

Code of Federal Regulations, 2013 CFR

...paragraph (c)(2) of this section. (1) Specification. Polycarbonate resins can be identified by their characteristic infrared spectrum. (2) Extractives limitations. The polycarbonate resins to be tested shall be ground or cut into small...

2013-04-01

278

21 CFR 177.1585 - Polyestercarbonate resins.  

Code of Federal Regulations, 2013 CFR

...Specifications. Polyestercarbonate resins identified in paragraph (a) of this section can be identified by their characteristic infrared spectrum. The resins shall comply with either or both of the following specifications: (i) The solution intrinsic...

2013-04-01

279

21 CFR 872.3140 - Resin applicator.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

280

Method for loading resin beds  

DOEpatents

An improved method of preparing nuclear reactor fuel by carbonizing a uranium loaded cation exchange resin provided by contacting a H.sup.+ loaded resin with a uranyl nitrate solution deficient in nitrate, comprises providing the nitrate deficient solution by a method comprising the steps of reacting in a reaction zone maintained between about 145.degree.-200.degree. C, a first aqueous component comprising a uranyl nitrate solution having a boiling point of at least 145.degree. C with a second aqueous component to provide a gaseous phase containing HNO.sub.3 and a reaction product comprising an aqueous uranyl nitrate solution deficient in nitrate.

Notz, Karl J. (Oak Ridge, TN); Rainey, Robert H. (Knoxville, TN); Greene, Charles W. (Knoxville, TN); Shockley, William E. (Oak Ridge, TN)

1978-01-01

281

Condensate-polisher resin-leakage quantification and resin-transport studies. [PWR  

Microsoft Academic Search

The objectives of this program were to: (1) determine the extent of resin leakage from current generation condensate polisher systems, both deep bed and powdered resin design, during cut-in, steady-state and flow transient operation, (2) analyze moisture separator drains and other secondary system samples for resin fragments and (3) document the level of organics in the secondary system. Resin leakage

C. C. Stauffer; P. L. Doss

1983-01-01

282

Penetration of etched enamel and dentin cavity surfaces by bonding agent/composite resin.  

PubMed

Mechanical and adhesive advantage of resin bonding agents depend upon the ability to penetrate microspaces created with acid-etchants and close adaptation to cavity surfaces. As a replicating material, these resins may reveal morphologic characteristics of the cavity surfaces not seen by direct scanning electron microscope (SEM) investigation. The purpose of this study was to describe, with the SEM, the resin replications of acid-etched cavity walls of Class V cavity preparations in the labial and lingual surfaces of extracted premolar teeth. Cavities were prepared in the gingival third of these surfaces in 26 freshly extracted human premolar teeth using fissure burs in water-cooled, high-speed handpieces. The cavosurface margins were bevelled. The preparations were washed in tap water, dried, etched for 20 seconds with 35% phosphoric acid, coated with light-cured bonding agent and filled with light-cured composite resin in two applications. The teeth were dissolved in acid and the cavity walls of the composite examined in the SEM. Features observed included: (a) Type II resin penetration of interrod regions, (b) resin penetration of the lamellae to the dentino-enamel junction (DEJ), (c) a 10-20 microns step in surface contour at the DEJ, with penetration of terminal tubule branches, (d) insular regions of deep dentin tubule penetration and (e) 100-300 microns deep, 10-30 microns incremental microlamellar penetrations into the enamel at the DEJ corresponding to enamel tufts. PMID:2083476

Brady, J M; Clarke-Martin, J A

283

Process for the preparation of lactic acid and glyceric acid  

DOEpatents

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

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

2008-12-02

284

The management of defective resin composite restorations: current trends in dental school teaching in Japan.  

PubMed

SUMMARY Aim: The aim of this article is to investigate the contemporary teaching of the management of defective direct resin composite restorations in dental schools in Japan. Methods: A questionnaire relating to the teaching of the management of defective resin composite restorations was developed and e-mailed to 29 dental schools in Japan in 2010. Results: Completed responses were received from 19 of the 29 invited schools (response rate = 66%). Eighteen schools (95%) report that they included the teaching of repair of direct defective resin composite restorations in their dental school programs. Thirteen schools reported that they included both clinical and didactic instruction on the repair of direct resin composite restorations. Fourteen schools did not teach any mechanical roughening of the exposed resin composite restoration surface before undertaking a repair. The most commonly reported treatment was acid etching with phosphoric acid (12 schools). The most commonly taught material for completing repairs was a flowable resin composite (16 schools). Conclusion: The teaching of repair of defective resin composite restorations is well established within many Japanese dental schools, to a greater extent than in some other regions of the world. The impact of this teaching on subsequent clinical practices in Japan should be investigated. Furthermore, it is concluded that there is a need for much stronger leadership in operative and conservative dentistry, ideally at the global level, to resolve differences in key aspects of operative procedures such as repairs. PMID:23550913

Lynch, Cd; Hayashi, M; Seow, Ll; Blum, Ir; Wilson, Nhf

2013-04-03

285

Fluid Resin Technic of Processing Denture Bases.  

National Technical Information Service (NTIS)

The fluid resin technic of processing acrylic resin denture bases was recently adopted for use in the dental module of the Air Transportable Hospital. The new technic, described in detail in this review, utilizes a pourable auto-curing acrylic resin for t...

C. D. Miller G. L. Hall

1968-01-01

286

Hydrogen Peroxide as a Resin Cure Accelerator  

Microsoft Academic Search

The reaction of hydrogen peroxide with conventional resin adhesives was sufficiently exothermic for the heat to accelerate and improve resin cure in the hotpress. As a consequence, pressing times for medium density fibreboard, particleboard, and plywood could be reduced by up to 30% and, in some cases, better resin cure permitted a reduction in binder level. Differences in the interaction

K. M. Chapman; D. J. Jenkin

1986-01-01

287

Method for removing contaminants from plastic resin  

DOEpatents

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

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

2008-12-30

288

Method of removing contaminants from plastic resins  

DOEpatents

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

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

2008-11-18

289

Method of removing contaminants from plastic resins  

DOEpatents

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

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

2007-08-07

290

Method development for epoxy resin analysis  

Microsoft Academic Search

Epoxy resin based negative photo resists are showing interesting properties which are useful for a series of applications\\u000a in electronic industries (Mark et al. in Encyclopedia of polymer science and engineering, Wiley, New York, 1986; Potter in Epoxide resins, Springer, New York, 1970; May and Tanka in Epoxy resin chemistry and technology, Marcel Dekker, New York, 1973; Bauer in Epoxy

Sawa Nordt; Harald Pasch; Wolfgang Radke

2010-01-01

291

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

292

Solvent impregnated resin for isolation of U(VI) from industrial wastes  

SciTech Connect

A solid-phase extraction method based upon impregnation of Cyanex 302 (bis(2,4,4- trimethylpentyl)mono-thio-phosphinic acid) on Amberlite XAD-2 resin is proposed for isolation of U(VI) from uranmicrolite ore tailing samples and industrial effluent samples. U(VI) was sorbed from nitric acid media on the solvent-impregnated resin (SIR) and was recovered completely with 1.0 M HCl. Based upon sorption behavior of U(VI) with Cyanex 302, it was quantitatively sorbed on the SIR in a dynamic method, while the other metal ions were not sorbed by the modified resin. The preparation of impregnated resin is simple, based upon physical interaction of the extractant and solid support, has good sorption capacity for U(VI), and is also reliable for detection of traces of U(VI). (authors)

Karve, M.; Rajgor, R.V. [Department of Chemistry, University of Mumbai, Vidyanagari, Mumbai-400098 (India)

2008-07-01

293

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

294

[New low temperature initiator system for dental adhesive resins. Application of peroxyesters with carboxyl group].  

PubMed

Adhesion between dentin and MMA resin was investigated using chemically activated initiator system consisting of 1,3,5-trimethyl-2-thiobarbituric acid, cupric salt, chloride ion, and tert.-butyl peroxymaleic acid (MA) with carboxyl group which usually has affinity to tooth. The adhesive strength of the MMA/PMMA resin to bovine dentin increased significantly to 8-10 MPa by addition of MA, while the adhesive strength was 4 MPa without MA. When the bonding broke at higher than 7 MPa, the adhesive resin layer usually fractured cohesively and the interfacial fracture did not occur. The bond strength obtained in this experiment was comparable to that obtained with MMA resin using TBBO and ferric ion initiator system which is known as the best initiator system for dentin available. PMID:2135549

Ohta, T; Kadoma, Y; Imai, Y

1990-11-01

295

Powdered epoxy resin test methods  

Microsoft Academic Search

The author describes several test methods which may be used to evaluate powdered epoxy resins for their potential use as integral insulation on fractional horsepower motor iron. These are the edge coverage test method, the hot plate gel time test method, the glass pellet flow test method, and the steel panel impact test method. These test methods may be of

N. Hanssen

1991-01-01

296

Imide Modified Epoxy Matrix Resins.  

National Technical Information Service (NTIS)

The results of a program designed to develop tough imide modified epoxy resins cured by bisimide amine (BIA) hardeners are described. State-of-the-art epoxides MY720 and DER383 were used, and four bismide amines were evaluated. These were the BIA's derive...

D. A. Scola

1984-01-01

297

Solventless Amine Epoxy Resin System.  

National Technical Information Service (NTIS)

A solventless amine-epoxy resin system is made up of (1) a binary aromatic amine mixture of 2,6-diaminopyridine and meta-phenylene diamine in a weight ratio of from about 1:4 to about 4:1; and (2) an epoxy mixture of (a) the diglycidyl ether of bisphenol ...

E. J. Rhyn K. R. Foote G. S. Handler J. P. Diebold

1977-01-01

298

Chelate Polymers of Phenolic Resin  

Microsoft Academic Search

Chelate polymers of the resin poly[3,5-(l-carboxy-2-hydroxy phenylene)ethyiene] with such bivalent ions as copper, nickel, cobalt, zinc, manganese, and trivalent iron have been synthesized. They have been analyzed, and some of their properties have been determined. On the basis of these, a polymeric structure is assigned to the polychelates.

M. N. Patel; J. B. Patel

1983-01-01

299

High-performance epoxy casting resins for SMD-LED packaging  

Microsoft Academic Search

In order to come up with high volume SMD-LED production encompassing 1.9 billion devices for current fiscal year we did basic exploratory work to establish structure-processing- property relations for robust epoxy casting resin packages with identical ppm level of one. Bisphenol A-based epoxy casting resins (DGEBA) with acidic ester modified Hexahydrophthalic anhydride (HHPA) hardeners using strictly controlled high-grade raw materials

Georg Bogner; Alexandra Debray; Klaus Hoehn

2000-01-01

300

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

301

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

302

Study of Curing Kinetics and Thermal Degradation of UV Curable Epoxy Acrylate Resin  

Microsoft Academic Search

Blends of epoxy acrylate resins (acid values 3, 6.5 & 10 mg KOH\\/gm Solid) with monofunctional monomers (ethoxylated phenol monoacrylate) were prepared by physical mixing, having weight ratio 50:50. These blends were cured by using UV radiations in presence of photo initiator (Darocure 1173). The thermal degradation kinetics of these resin blends were studied, using thermo gravimetric analysis in nitrogen

AMRITA SHARMA; DEVENDRA AGARWAL; JAGABIR SINGH

303

Synthesis of chelating resins and its application in ligand exchange chromatography  

Microsoft Academic Search

Three kinds of new chelating resin containing ß-hydroxydithiocinnamic acid, ethyl ß-hydroxydithiocinnamate and N-(hydroxymethyl)-thioamide functional groups were synthesized. Cu(II), Cd(II) and Hg(II) were used as complex forming metal ions. By varying the combination of metal ion and chelating resin, a great variety of separation systems could be realized. For the on-line trace enrichment of 2-mercaptobenzimidazole, the copper-loaded N-(hydroxymethyl)-thioamide concentration column was

Chuen-Ying Liu; Cho-Chun Hu; Kuo-Ying Yeh; Min-Jane Chen

1991-01-01

304

Diclofenac removal in urine using strong-base anion exchange polymer resins.  

PubMed

One of the major sources of pharmaceuticals in the environment is wastewater effluent of which human urine contributes the majority of pharmaceuticals. Urine source separation has the potential to isolate pharmaceuticals at a higher concentration for efficient removal as well as produce a nutrient byproduct. This research investigated the efficacy of using strong-base anion exchange polymer resins to remove the widely detected and abundant pharmaceutical, diclofenac, from synthetic human urine under fresh and ureolyzed conditions. The majority of experiments were conducted using a strong-base, macroporous, polystyrene resin (Purolite A520E). Ion-exchange followed a two-step removal rate with rapid removal in 1 h and equilibrium removal in 24 h. Diclofenac removal was >90% at a resin dose of 8 mL/L in both fresh and ureolyzed urine. Sorption of diclofenac onto A520E resin was concurrent with desorption of an equivalent amount of chloride, which indicates the ion-exchange mechanism is occurring. The presence of competing ions such as phosphate and citrate did not significantly impact diclofenac removal. Comparisons of three polystyrene resins (A520E, Dowex 22, Dowex Marathon 11) as well as one polyacrylic resin (IRA958) were conducted to determine the major interactions between anion exchange resin and diclofenac. The results showed that polystyrene resins provide the highest level of diclofenac removal due to electrostatic interactions between quaternary ammonium functional groups of resin and carboxylic acid of diclofenac and non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Diclofenac was effectively desorbed from A520E resin using a regeneration solution that contained 4.5% (m/m) NaCl in an equal-volume mixture of methanol and water. The greater regeneration efficiency of the NaCl/methanol-water mixture over the aqueous NaCl solution supports the importance of non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Experiments with ketoprofen, in addition to diclofenac, suggest that polystyrene anion exchange resins can be used to selectively remove other acidic pharmaceuticals from urine. PMID:24029637

Landry, Kelly A; Boyer, Treavor H

2013-08-27

305

Method of recovering hazardous waste from phenolic resin filters  

DOEpatents

The invention is a process for the recovery of hazardous wastes such as heavy metals and radioactive elements from phenolic resin filter by a circulating a solution of 8 to 16 molar nitric acid at a temperature of 110 to 190 degrees F. through the filter. The hot solution dissolves the filter material and releases the hazardous material so that it can be recovered or treated for long term storage in an environmentally safe manner.

Meikrantz, David H. (Idaho Falls, ID); Bourne, Gary L. (Idaho Falls, ID); McFee, John N. (Albuquerque, NM); Burdge, Bradley G. (Idaho Falls, ID); McConnell, Jr., John W. (Idaho Falls, ID)

1991-01-01

306

Alkyd resins: From down and out to alive and kicking  

Microsoft Academic Search

Alkyd resins have been introduced in the 1930s as binders for paints. Their compatibility with many polymers and the extremely wide formulating latitude made them suitable for the production of a very broad range of coating materials. This includes do-it-yourself paints and varnishes for wood and metal, road marking paints, anticorrosive paints, nitrocellulose lacquers, two-component isocyanate curing coatings, acid curing

Ad Hofland

307

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

308

Effect of chitosan/riboflavin modification on resin/dentin interface: spectroscopic and microscopic investigations.  

PubMed

The aim of this study is to investigate the morphological and chemical changes of demineralized dentin collagen-matrix and resin/dentin interface associated with chitosan/riboflavin modification. Dentin disc specimens were prepared from sound molars, acid-etched with 35% phosphoric acid and modified with either 0.1% riboflavin or chitosan/riboflavin (Ch/RF ratios 1:4 or 1:1) and photo-activated by UVA. Morphological and chemical changes associated with surface modification were characterized by SEM and micro-Raman spectroscopy. Dentin surfaces of sound molars were exposed, acid-etched, and modified as described before. Etch-and-rinse dentin adhesive was applied, light-cured, and layered with resin-restorative composite. The resin infiltration and resin/dentin interface were characterized by micro-Raman spectroscopy and SEM. An open-intact collagen network-structure, formation of uniform hybrid-layer and higher resin infiltration were found with 0.1%RF and Ch/RF 1:4 modifications. Raman analysis revealed chemical changes and shifts in Amide bands with the modification of dentin collagen-matrix. The use of riboflavin and chitosan/riboflavin formulations to modify dentin-collagen matrix, with the defined ratios, stabilizes the collagen fibrillar network and enhances resin infiltration and hybrid layer formation. These preliminary results are encouraging for subsequent consideration of chitosan/riboflavin modification in adhesive dentistry. PMID:23184366

Daood, Umer; Iqbal, Kulsum; Nitisusanta, Lorraine I; Fawzy, Amr S

2012-11-27

309

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...

310

Separation of Actinium-227 from Its Daughter Products by Cationic Resins Technique.  

National Technical Information Service (NTIS)

A method for separating actinium-227 from its daughter products based on ion exchange principle is shown. Radionuclides mixture in perchloric acid 8,5 N and chloridric acid 0,5 N medium pass by a cationic resin column. Thorium-227 and actinium-227, which ...

M. J. C. Nastasi

1976-01-01

311

Column chromatographic separation of Y{sup 3+} from Sr{sup 2+} by polymeric ionizable crown ether resins  

SciTech Connect

Condensation polmers containing subunits of crown ether carboxylic acid monomers are effective stationary phases for the chromatographic separation of Y{sup 3+} and Sr{sup 2+}. The pH range and metal loading capacities for the resins have been determined under equilibrium conditions. The resin can be regenerated for repeated use without losing its separation capability. Altering the molecular structure of the monomer (sym-dibenzo-16-crown-5-oxyacetic acid) by an alkyl substitution on the macrocyclic cavity decreases the loading capacity of the resin.

Wood, D.J.; Elshani, S.; Wai, C.M. [Idaho Univ., Moscow, ID (United States). Dept. of Chemistry; Bartsch, R.A. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry; Huntley, M.; Hartenstein, [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States)

1993-10-01

312

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

313

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

314

Three new xanthones from the resin of Garcinia hanburyi.  

PubMed

Three new xanthones, 22,23-dihydroxydihydrogambogenic acid (1), 12-hydroxygambogefic acid A (2), and hanburixanthone (3), along with thirteen known compounds were isolated from the resin of Garcinia hanburyi. The structures of the new compounds were determined by detailed analysis of 1D and 2D NMR spectra and by comparison with related model compounds. All compounds were tested for their cytotoxicities against A549, HCT116, and MDA-MB-231, and most of them showed significant effects on the cell lines. PMID:23670620

Deng, Yun-Xia; Guo, Tao; Shao, Zhi-Yu; Xie, Hui; Pan, Sheng-Li

2013-05-13

315

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

2013-10-04

316

Extraction of High Quality DNA from Seized Moroccan Cannabis Resin (Hashish)  

PubMed Central

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.

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

2013-01-01

317

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

318

Solubilization of hydroxyapatite at neutral pH by an anionic ionic exchange resin.  

PubMed

Sucrose, induced dental plaque has been shown to contain high amounts of lipoteichoic acids, a bacterial anionic polymer with chemical properties similar to ionic exchange resins. The present study describes an in vitro experiment where a commercial resin Amberlite IR 120 was shown to dissolve hydroxyapatite at neutral pH. The resin binds calcium and the dissociation of the hydroxyapatite Ca5(PO4)3OH leads to 5Ca++ +3 PO4(-3) + OH- is driven to the right as long as the resin takes up calcium. The dissociation of the hydroxyapatite was monitored by electrical conductivity and pH of the aqueous phase. It is suggested that this mechanism may be of some significance in vivo. PMID:6937087

Rölla, G; Bergseth, H; Svatun, B

1980-01-01

319

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

320

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

321

Tactile learning in resin foraging honeybees  

Microsoft Academic Search

Honeybees harvest and use plant resins in a mixture called propolis to seal cracks and smooth surfaces in the nest architecture.\\u000a Resins in the nest may be important in maintaining a healthy colony due to their antimicrobial properties. This study had\\u000a two main objectives: (1) Provide initial insight on the learning capabilities of resin foraging honeybees; (2) analyze the\\u000a sensitivity

Michael Simone-Finstrom; Joel Gardner; Marla Spivak

2010-01-01

322

Pharmaceutical Applications of Ion-Exchange Resins  

Microsoft Academic Search

The historical uses of ion-exchange resins and a summary of the basic chemical principles involved in the ion-exchange process are discussed. Specific applications of ion-exchange resins are provided. The utility of these agents to stabilize drugs are evaluated. Commonly occurring chemical and physical incompatibilities are reviewed. Ion-exchange resins have found applicability as inactive pharmaceutical constituents, particularly as disintegrants (inactive tablet

David P. Elder

2005-01-01

323

Induction of isoprenyl diphosphate synthases, plant hormones and defense signalling genes correlates with traumatic resin duct formation in Norway spruce (Picea abies).  

PubMed

Norway spruce (Picea abies) defends itself against herbivores and pathogens by formation of traumatic resin ducts filled with terpenoid-based oleoresin. An important group of enzymes in terpenoid biosynthesis are the short-chain isoprenyl diphosphate synthases which produce geranyl diphosphate (C(10)), farnesyl diphosphate (C(15)), and geranylgeranyl diphosphate (C(20)) as precursors of monoterpenes, sesquiterpenes, and diterpene resin acids, respectively. After treatment with methyl jasmonate (MJ) we investigated the expression of all isoprenyl diphosphate synthase genes characterized to date from Norway spruce and correlated this with formation of traumatic resin ducts and terpene accumulation. Formation of traumatic resin ducts correlated with higher amounts of monoterpenes, sesquiterpenes and diterpene resin acids and an upregulation of isoprenyl diphosphate synthase genes producing geranyl diphosphate or geranylgeranyl diphosphate. Among defense hormones, jasmonate and jasmonate-isoleucine conjugate accumulated to higher levels in trees with extensive traumatic resin duct formation, whereas salicylate did not. Jasmonate and ethylene are likely to both be involved in formation of traumatic resin ducts based on elevated transcripts of genes encoding lipoxygenase and 1-aminocyclopropane-1-carboxylic acid oxidase associated with resin duct formation. Other genes involved in defense signalling in other systems, mitogen-activated protein kinase3 and nonexpressor of pathogenesis-related gene1, were also associated with traumatic resin duct formation. These responses were detected not only at the site of MJ treatment, but also systemically up to 60 cm above the site of treatment on the trunk. PMID:22002747

Schmidt, Axel; Nagel, Raimund; Krekling, Trygve; Christiansen, Erik; Gershenzon, Jonathan; Krokene, Paal

2011-10-15

324

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

325

Microbiological Study of Water-Softener Resins  

PubMed Central

Microbial identification using effluents backflushed from exhausted urban and rural tank resins and cleaned resins containing the sulfonated copolymer of styrene and divinylbenzene (SDB) were completed, along with microbial assessment of the concentrated stock salt brine. Forty-four different bacterial and fungal genera were identified. Extensive biochemical and animal virulence tests completed on one of the six bacterial salt brine isolates indicated a pathogenic staphylococcal strain. The retention of Staphylococcus aureus, a Flavobacterium sp, and Escherichia coli B bacteriophage was demonstrated both by using the nonexhausted sodium-regenerated resin and by using the same resin exchanged with different mono-, di-, and trivalent cations. Effluent counts completed after bacterial seepage through the resins indicated the Pb++ exchanged resin removed 55% of the bacteria; Na+, Fe++, and Al+++ removed 31 to 36% and Ca++ and Cu++ removed about 10 to 15%. Seventy per cent or more of the bacteriophage was removed by Fe++, Cu++, and Al+++, whereas the Ca++ and Na++ cations removed 25 to 31%. Over a 77-day period, nonsterile tap water was passed through bacterial seeded and uninoculated SDB (Na) resin columns. Effluent and resin elution counts demonstrated the growth and survival of 2 different bacteria per column. Increased bacterial retention, survival, and multiplication occurred concomitantly with accumulation of organic and inorganic materials and the Ca++ and Mg++ cations from the tap water. Furthermore, microbial elution from resin particles taken from column depths of 1, 8, and 16 cm indicated a bacterial diminution with increasing depths.

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

1969-01-01

326

21 CFR 173.40 - Molecular sieve resins.  

Code of Federal Regulations, 2010 CFR

...40 Molecular sieve resins. Molecular sieve resins may be safely used...prescribed conditions: (a) The molecular sieve resins consist of purified dextran having an average molecular weight of 40,000,...

2010-01-01

327

21 CFR 173.40 - Molecular sieve resins.  

Code of Federal Regulations, 2010 CFR

...40 Molecular sieve resins. Molecular sieve resins may be safely used...prescribed conditions: (a) The molecular sieve resins consist of purified dextran having an average molecular weight of 40,000,...

2009-04-01

328

75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan  

Federal Register 2010, 2011, 2012, 2013

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

2010-11-01

329

40 CFR 721.3135 - Phosphorous modified epoxy resin (generic).  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Phosphorous modified epoxy resin (generic...Chemical Substances § 721.3135 Phosphorous modified epoxy resin (generic...substance identified generically as a phosphorous modified epoxy resin (PMNs...

2009-07-01

330

40 CFR 721.3135 - Phosphorous modified epoxy resin (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Phosphorous modified epoxy resin (generic...Chemical Substances § 721.3135 Phosphorous modified epoxy resin (generic...substance identified generically as a phosphorous modified epoxy resin (PMNs...

2010-07-01

331

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Epoxy resin containing phosphorus (generic). 721.2752 Section...721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance...generically as an epoxy resin containing phosphorus (PMN P-00-912) is subject...

2013-07-01

332

Different surface preparation techniques of porcelain repaired with composite resin and fracture resistance  

PubMed Central

Background: Porcelain from prosthesis such as crown or bridge can be fractured if exposed to trauma; and, can be repaired at chairside using composite resin. Aim: To investigate the fracture resistance of few techniques of surface preparation in repairing fractured porcelain using composite resin. Materials and Methods: Eighty samples of porcelain blocks were divided into 4 groups for different surface preparations, such as, Cimara repairing kit; porcelain etch kit containing hydrofluoric acid; Panavia F resin cement; and, sandblasting using aluminium oxide, before composite resin (Filtek Z250, 3M ESPE) was bonded to the prepared porcelain blocks. Twenty others samples in the control group comprised of pure porcelain blocks. The fracture resistance of each sample was tested using Instron machine (UK). Results: With the exception of the group repaired using hydrofluoric acid (3.04±1.04 Mpa), all the other groups showed significant difference in the fracture resistance values when compared to the control group (3.05 ± 1.42 MPa) at P<0.05. Conclusions: Etching of the porcelain blocks with hydrofluoric acid holds promise in the repair of fractured porcelain with composite resin at chairside.

Abd Wahab, Mohd Helmy Khalid; Bakar, Wan Zaripah Wan; Husein, Adam

2011-01-01

333

In Vitro Mutagenicity Testing. I. Kermide 601 Resin, Sylgard 184 Encapsulating Resin, and Sylgard 184 Curing Agent.  

National Technical Information Service (NTIS)

Five compounds, Kerimide 601 resin, Sylgard 184 encapsulating resin, Sylgard 184 curing agent, benzo(a)pyrene, and acridine orange were tested for in vitro mutagenicity using the Ames Salmonella assay system. Kerimide 601 resin, Sylgard 184 encapsulating ...

S. Y. Wang D. M. Smith

1978-01-01

334

NEW CATION EXCHANGE RESINS BASED ON POLYVINYL ALCOHOL CONTAINING CARBOXYL GROUPS FOR THE REMOVAL OF SOME TEXTILE CONTAMINANTS FROM AQUEOUS SOLUTIONS  

Microsoft Academic Search

Two cation exchange resins having carboxyl contents, 628 and 424 meq\\/100 g sample were prepared by free radical polymerization of acrylic acid in presence of polyvinyl alcohol aqueous solution using methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. The prepared resins were characterized by investigation of their potentiometric titration, durability, water solubility, and swellability. The removal of Cu ions (in

H. M. Fahmy; Z. El-Sayed

2002-01-01

335

[Contact allergy to epoxy resins plastics based on materials collected by the Nofer Institute of Occupational Medicine].  

PubMed

Of the 5604 patients examined in 1984-2001 for suspected occupational dermatitis, 160 persons (2.8%) showed allergy to epoxy resins plastics. Allergy was more frequent in men (4.9%) than in women (1.2%); in 154 persons, allergy was of occupational etiology (in a group of 160 patients with allergy to epoxy resins, the following proportions were observed: bricklayers, platelayers--17.5%; fitters, turners, machinist millers--13.8%; plastics molders--13.1%; laminators--11.3%; electrical equipment assemblers--10.6%; painters--10.0%). Having compared the frequency of allergy to components of epoxy resins in the years 1984-1993 and 1994-2001, it was found that allergy to resin, reactive diluents and plasticizers was on increase, whereas allergy to amines and acid anhydrides hardeners was on decrease. In a group of 13 chemical compounds entering into the composition of epoxy resins, epoxy resin contributed to the largest number of positive patch tests (77.5% of epoxy-allergic persons). This was followed by triethylenetetramine (23.1%), ethylenediamine (13.1%), phthalic anhydride (8.1%), diethylenetetramine (6.9%) and phenylglycidylether (6.2%). In addition, three patients reacted to both epoxy resin and cycloaliphatic resin. PMID:12923997

Kie?-Swierczy?ska, Marta; Krecisz, Beata

2003-01-01

336

Ion exchange and protonation equilibria of an amphoteric ion-exchange resin in the presence of simple salt.  

PubMed

The influence of simple salts on the ion exchange and protonation equilibria of an amphoteric ion-exchange resin, which has strong base and weak acid moieties in a single functional group fixed onto the styrene-DVB matrix, has been investigated. Concentrations of ionic species in the amphoteric ion-exchange resin in equilibrium with various sodium salt solutions were estimated by (23)Na NMR spectroscopy. For the NaClO(4) system, the ratio of sodium ion concentration in the resin phase to that in the equilibrium solution was greater than 1 and increased with a decrease in the salt concentration. In contrast to an ordinary cation-exchange resin, the ion exchange behavior of Mg(2+) and Ca(2+) on the amphoteric ion-exchange resin showed a marked dependence on the kinds of salts: the distribution coefficients for the NaCl system were independent of the salt concentration, while the log D vs. log[Na(+)] plots for the NaClO(4) system showed linear relationships with slopes being neither -2 nor 0. Apparent protonation constants of the carboxylate in the functional group of the resin in equilibrium with NaClO(4) solutions were greater than those with NaCl solutions. The ion exchange and protonation properties of the amphoteric ion-exchange resin were elucidated on the basis of the information about the salt concentrations in the resin phase estimated by the NMR method. PMID:18781023

Miyazaki, Yoshinobu; Qu, Hui; Konaka, Junko

2008-09-01

337

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

PubMed Central

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

2013-01-01

338

Tubular occlusion optimizes bonding of hydrophobic resins to dentin.  

PubMed

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

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

2007-06-01

339

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

340

Ceramic Whisker Reinforcement of Dental Resin Composites  

Microsoft Academic Search

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

H. H. K. Xu; T. A. Martin; J. M. Antonucci; EC Eichmiller

1999-01-01

341

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. Dalil; Lu, Ping-Hung; Cook, Michelle M.

1997-07-01

342

Prophylaxis with resin in wood ants  

Microsoft Academic Search

Animals may use plant compounds to defend themselves against parasites. Wood ants, Formica paralugub- ris, incorporate pieces of solidified conifer resin into their nests. This behaviour inhibits the growth of bac- teria and fungi in nest material and protects the ants against some detrimental microorganisms. Here, we studied the resin-collecting behaviour of ants under field and laboratory conditions. First, we

Gregoire Castella; Michel Chapuisat; Philippe Christe

2008-01-01

343

Epoxy resin composition having improved wetting properties  

US Patent & Trademark Office Database

An improved epoxy resin composition comprising an epoxy resin suitable for adhesive, potting or laminating use mixed with from about 0.1% to about less than 3% of an oxazolidine ester represented by the formula: ##EQU1## where R is an alkyl or alkenyl group of from 5 to 21 carbon atoms.

Sausaman; David K. (Terre Haute, IN)

1976-04-20

344

Fluoroaliphatic Cyanate Resins for Low Dielectric Applications.  

National Technical Information Service (NTIS)

The present invention is a cyanate resin monomer having the formula: NCO-CH2-(CF2)n-CH2-OCN where n is an even integer from 6 to 10, inclusive. Another aspect of the invention is an essentially pure cyanate resin monomer having the formula: NCO-CH2-(CF2)n...

A. W. Snow L. J. Buckley

1996-01-01

345

Hydraulic fracturing using reinforced resin pellets  

Microsoft Academic Search

A method of fracturing subterranean formations surrounding oil wells, gas wells, and similar boreholes is presented. The method employs a propping agent which permits the fractures to be propped in a partial monolayer pattern. It has been found that fractures with surprisingly high conductivities can be obtained by use of propping agents composed of reinforced synthetic resins. Synthetic resins without

1972-01-01

346

Fluorinated diamond bonded in fluorocarbon resin  

DOEpatents

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

347

Adsorption of pesticides on resins.  

PubMed

The objective of this work was to assess the capability of organic hydrophobic polymeric resins Amberlite XAD-4 and XAD-7 to remove the pesticides alachlor and amitrole from water. The pesticides adsorption on the two different adsorbents was measured by batch equilibrium technique and isotherm types and parameters were estimated. Two theoretical models were applied based on a Freundlich and a Langmuir isotherms. The effect of pesticides chemical composition and structure as well as the nature of solid surface on the efficiency of adsorption was evaluated. The influence of pH also was studied. In low pH solutions adsorption of amitrole was higher upon the nonionic aliphatic acrylic ester copolymer XAD-7 in comparison to the nonionic, crosslinked macroreticular copolymer of styrene divinylbenzene XAD-4. In neutral and intermediate pH solutions the polar acrylic ester copolymer XAD-7 was more effective to the retention of alachlor. The acrylic ester copolymer showed at pH 3 the lower effectiveness in alachlor removal from water. The data of the adsorption isotherms of pesticides upon the examined polymeric resins seemed to conform to both the Freundlich and the Langmuir isotherm models. PMID:12617554

Kyriakopoulos, Grigorios; Hourdakis, Adamadia; Doulia, Danae

2003-03-01

348

Continuous metal removal technique for resist resins  

NASA Astrophysics Data System (ADS)

Modern resists require very pure raw materials to insure highest quality images. Many methods have been developed to reduce metals in resins used to make photoresists. Extractive washing techniques and ion exchange methods have been the predominant methods used to reduce metal levels for these critical raw materials. This has been especially important for the novolak resins because of the generally poor quality of the starting materials used to make them and by the nature of the resin isolation steps traditionally used. Both of the commonly used cleaning methods are time consuming and are predominantly batch processes. Based upon techniques developed to efficiently fractionate resins, we have developed a technique for the rapid, continuous reduction of metal contaminants in film forming resin solutions by an extractive method using a double inlet liquid/liquid centrifuge.

Wanat, Stan F.; McKenzie, Douglas S.; Rahman, M. D.

2001-08-01

349

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

PubMed

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

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

2005-01-25

350

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

351

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

352

Rapid determination of alpha emitters using Actinide resin.  

PubMed

The European Commission has recently published the recommended radiological protection criteria for the clearance of building and building rubble from the dismantling of nuclear installations. Radionuclide specific clearance levels for actinides are very low (between 0.1 and 1 Bq g(-1)). The prevalence of natural radionuclides in rubble materials makes the verification of these levels by direct alpha counting impossible. The capability of Actinide resin (Eichrom Industries, Inc.) for extracting plutonium and americium from rubble samples has been tested in this work. Besides a strong affinity for actinides in the tri, tetra and hexavalent oxidation states, this extraction chromatographic resin presents an easy recovery of absorbed radionuclides. The retention capability was evaluated on rubble samples spiked with certified radionuclide standards (239Pu and 241Am). Samples were leached with nitric acid, passed through a chromatographic column containing the resin and the elution fraction was measured by LSC. Actinide retention varies from 60% to 80%. Based on these results, a rapid method for the verification of clearance levels for actinides in rubble samples is proposed. PMID:15177360

Navarro, N; Rodriguez, L; Alvarez, A; Sancho, C

353

Anion-exchange resin-based desulfurization process  

SciTech Connect

Under DOE Grant No. DE-FG22-90PC90309, the University of Tennessee Space Institute (UTSI) is contracted to further develop its anion-exchange, resin-based desulfurization concept to desulfurize alkali metal sulfates. From environmental as well as economic viewpoints, it is necessary to remove soluble sulfates from the wastes created by flue gas desulfurization systems. In order to do this economically, a low-cost desulfurization process for spent sorbents is necessary. UTSI's anion-exchange resin-based desulfurization concept is believed to satisfy these requirements. During the reporting period, October 1, 1992--December 31, 1992, UTSI has completed the batch mode experiments to evaluate the performance enhancement effect caused by organic acids on the resin's exhaustion efficiency. At present, batch mode experiments are being conducted to locate the position of the CO[sub 3]= and SO[sub 4]= ions in the affinity chart, and also reviewing/assessing the ASPEN Code's capabilities for use in the development of the Best Process Schematic and related economics.

Sheth, A.C.; Dharmapurikar, R.

1992-01-01

354

Diphonix{reg_sign} resin: A review of its properties and applications  

SciTech Connect

The recently developed Diphonix{reg_sign} 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. Therefore the resin has potential for 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. In view of the above applications the 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 obtained in the studies on the properties of 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 and fuel processing 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); Gula, M.J. [Eichrom Industries, Inc., Darien, IL (United States)

1997-01-01

355

Evaluation of chelating ion-exchange resins for separating Cr(III) from industrial effluents.  

PubMed

In this study two chelating resins containing iminodiacetic acid groups (Amberlite IRC 748 and Diaion CR 11) and a chelating resin based on sulfonic and diphosphonic acid groups (Diphonix) were investigated in order to separate Cr(III) from industrial effluents produced in hard and decorative electroplating. Samples of two industrial plants were characterized during a period of about one year and a half in terms of the metals content (Cr, Cu, Na, Ca, Fe and Ni), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), Chemical Oxygen Demand (COD) and pH. Some of the physical properties of the resins, namely the moisture content, apparent density, intraparticle porosity and the particle size distribution were also evaluated. To quantify the sorption capacity of the resins, batch experiments were performed using synthetic solutions of Cr(III), as well as solutions of Fe in the case of Diphonix. The Langmuir and Langmuir-Freundlich isotherms enabled a good description of the ion-exchange equilibrium data, and the maximum sorption capacity determined for Amberlite and Diaion was 3.6 mequiv./g(dry resin). For Diphonix that parameter was 3.4 mequiv./g(dry resin). The Diphonix resin exhibits a high selectivity for transition metals (Fe, Ni) over the chromium trivalent. Therefore, it was screened as the most suitable for selectively removing those metal impurities from chromium electroplating effluents. For this resin, the sorption capacity is strongly dependent on the initial pH of the solution. Though, high regeneration efficiencies of Diphonix for stripping Cr(III) were found by using a mixture of NaOH/H(2)O(2). The mathematical model tested for describing the dynamics of the process allowed a good fitting to the experimental data and enabled the estimation of effective pore diffusivity of Cr(III). The saturations of Diphonix with industrial effluents demonstrated that the breakthrough capacity of the resin is affected by the presence of other species in solution, such as Fe and Ni. Nevertheless, these effluents may be treated with this resin, being possible to separate Cr(III) from other transition metallic ions in solution. PMID:19406569

Cavaco, Sofia A; Fernandes, Sandra; Augusto, Cátia M; Quina, Margarida J; Gando-Ferreira, Licínio M

2009-04-05

356

Methyl t-Butyl Ether (MTBE) Production: A Comparison of Montmorillonite-Derived Catalysts with an Ion-Exchange Resin  

Microsoft Academic Search

Montmorillonite-based catalysts were compared with an acidic ion-exchange resin of the type used industrially for the production of methyl t-butyl ether (MTBE) from methanol and isobutene or t-butanol. When 1,4-dioxan was used as solvent, Al3+-exchanged montmorillonites had about half the efficiency of the resin Arnberlyst 15 at 60~ they were, however, about twice as efficient at this temperature at Ti3+-montmorillonite

J. M. Adams; K. MARTIN; R. W. MCCABE; S. MURRAY

1986-01-01

357

Study on preparation and properties of epoxy resin modified by amine-terminated polyimide as electronic packaging materials  

Microsoft Academic Search

In this research, epoxy resin was modified by amine-terminated polyimide (ATPI) prepolymer for improving both thermal and mechanical properties of electronic packaging materials. The ATPI was synthesized with polyester and pyromellitic dianhydride (PMDA), p-toluene sulphonic acid (PTSA) as catalyst and characterized by FT-IR spectrum and DSC. The ATPI modified epoxy resin (AME) was cured by 4, 4-diaminodiphenyl ether (DDE). The

Xin Miao; Dayong Gui; Guangfu Zeng; Jianhong Liu

2010-01-01

358

A comparative study of two chelating ion-exchange resins for the removal of chromium(III) from aqueous solution  

Microsoft Academic Search

Macroporous resins containing iminodiacetic acid (IDA) groups (Lewatit TP 207 and Chelex-100) were investigated as a function of concentration, temperature and pH for their sorption properties towards chromium(III). The chromium(III) ions sorbed onto the resin and in the equilibrium concentration were determined by inductively coupled plasma spectrophotometer. The maximum sorption for chromium ions was observed at pH 4.5. Solution pH

F. Gode; E. Pehlivan

2003-01-01

359

Studies of ion-exchange resin complex of chloroquine phosphate.  

PubMed

High-potency adsorbates of chloroquine phosphate (CQP) were prepared by the batch method using a polyacrylic acid ion-exchange resin. Taste evaluation of the adsorbates shows significant masking of the bitterness of the drug. The complex formation was complete at pH 6.0. Stability studies at 37 degrees C, 45 degrees C, and 60 degrees C indicated that the complex was stable at all conditions for 1 month. In vitro release studies revealed complete drug elution from the complex at pH 1.2 and 2.0. PMID:10872097

Agarwal, R; Mittal, R; Singh, A

2000-07-01

360

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

361

Microleakage of class V resin composite restorations after conventional and Er:YAG laser preparation.  

PubMed

This in vitro study compared the microleakage of Class V resin composite restorations at bevelled enamel/composite and dentin/composite interfaces following Er:YAG laser (pre-treatment modalities: laser-etching and/or acid-etching) or conventional preparation and acid-etch, in association with two resin composite formulations and their three-step adhesive system. Class V cavities with conventional bevel produced on the lingual and buccal surfaces of eighty extracted caries- and restoration-free human teeth, were assigned to eight groups: cavities were or Er:YAG-lased and acid-etched (groups 1 and 5); or Er:YAG-lased, laser-etched and acid-etched (groups 2 and 6); or Er:YAG-lased and only laser-etched (groups 3 and 7); or cut by dental drill at high-speed and acid-etched (groups 4 and 8). The specimens were restored with Optibond FL+Herculite XRV (groups 1, 2, 3 and 4) or with Scotchbond MP+Z 100 (groups 5, 6, 7 and 8), stored in distilled water at 37 degrees C for 24 h, thermocycled 1500 times between 5 and 55 degrees C, placed in a 2% aqueous solution of methylene blue for 24 h at 37 degrees C, embedded in resin and sectioned. Microleakage was assessed according to the depth of dye penetration along the restoration. There were statistically significant differences between occlusal and cervical regions for all groups (P<0.01) except for groups 3 and 7. Pair-wise comparison of groups showed that acid-etch is advocated when using resin composite in Er:YAG-lased Class V cavities; the seal at enamel margins in Er:YAG-lased and laser-etched cavities depended on the resin composite formulation and corresponding adhesive (P<0.05). PMID:16102081

Delme, K I M; Deman, P J; De Moor, R J G

2005-09-01

362

Caries inhibition by a resin-modified and a conventional glass ionomer cement, in vitro  

Microsoft Academic Search

Objectives: The aim of this study was to compare inhibition, in vitro, of a resin-modified and a conventional glass ionomer cement.Methods: Standardized Class V cavities were prepared in extracted human molar teeth and restored with Fuji II LC (n = 14) or Chemfil II (n = 14) according to manufacturers' guidelines. The teeth were submerged in an acid gel (lactic

S. M. Dunne; J. S. Goolnik; B. J. Millar; R. P. Seddon

1996-01-01

363

Effect of coupling agent on mechanical properties of hollow carbon microsphere\\/phenolic resin syntactic foam  

Microsoft Academic Search

Various hollow carbon microspheres\\/phenolic resin syntactic foams were prepared by varying the content of hollow carbon microspheres. To improve the compressive and flexural strength and fracture toughness of syntactic foam, the hollow carbon microspheres were oxidized in nitric acid and followed by the treatment with a coupling agent of glutaric dialdehyde. Compression, flexural, and fracture toughness tests were performed to

Liying Zhang; J. Ma

2010-01-01

364

SEPARATION OF AMERICIUM AND CURIUM BY CHROMATOGRAPHIC TECHNIQUE USING TERTIARY PYRIDINE TYPE RESIN  

Microsoft Academic Search

The group separation of trivalent actinides and lanthanides and the mutual separation of americium and curium are necessary for the transmutation of americium. We have proposed the separation system based on the chromatography using the tertiary pyridine-type resin. In this separation system, the complete separation method of the trivalent actinides and lanthanides are already established using the hydrochloric acid and

Tatsuya Suzuki; Keisuke Itoh; Atsushi Ikeda; Yasuhiko Fujii; Masaki Ozawa; Mitsuo Hara; Toshiaki Mitsugashira

365

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

PubMed Central

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

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

2009-01-01

366

Method for the Preparation of Uranium Fuel Particles by Loading Ion Exchange Resin.  

National Technical Information Service (NTIS)

The complete loading of weakly acid resin particles could be attained by multi-stage exchange with uranyl nitrate solutions of growing concentration. The setting of pH-values for the individual stages was achieved by the addition of ammonia. For the techn...

N. Abd El Monem

1978-01-01

367

A Study of the Effect of Palm Oil on the Properties of a New Alkyd Resin  

Microsoft Academic Search

A new alkyd resin was synthesized by reacting glycerol, phthalic anhydride and mono fatty acid (palm oil) (Alkyd-P) in the presence of calcium oxide as a catalyst. At the first stage, palm oil was converted to monoglycerides as a polyol by alcoholysis. Esterification process was held at the second stage by adding phthalic anhydride and xylene in the mixture. FT-IR

368

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

369

Phenol-Formaldehyde Plywood Adhesive Resins Prepared with Liquefied Bark of Black Wattle (Acacia Mearnsii).  

National Technical Information Service (NTIS)

In this study, whole bark and tannin-free bark from black wattle were liquefied in phenol in the presence of sulfiric acid catalyst. The resulting solutions were reacted with formalin in basic solution to yield resol resins that had 33%. of the phenol rep...

A. H. Conner M. A. E. Santana M. G. D. Baumann

1996-01-01

370

Mesoporous MFI zeolite material from silica–alumina\\/epoxy-resin composite material and its catalytic activity  

Microsoft Academic Search

Although the versatilities of zeolitic materials are widely known to chemists and materials scientists, their exclusive microporosity sometimes causes various defections especially in the diffusion of reactant and product molecules in catalytic reactions. Silica–alumina\\/epoxy-resin composite materials were obtained from TMOS (tetramethoxysilane), aluminum acetylacetonate and bisphenol A diglycidyl ether with a cyclic acid anhydride as both condensation and curing reagents. Hydrothermal

Masahiro Fujiwara; Akinori Sakamoto; Kumi Shiokawa; Astam K. Patra; Asim Bhaumik

2011-01-01

371

Equilibrium and kinetic data of adsorption and separation for zirconium and hafnium onto MIBK extraction resin  

Microsoft Academic Search

The equilibrium and kinetics of methyl isobutyl ketone (MIBK) extraction resin for adsorption and separation of zirconium and hafnium were studied under the different conditions of acidity, initial total concentrations of zirconium and hafnium and temperature. The equilibrium data of both zirconium and hafnium are found to follow the Freundlich adsorption isotherm, and the Freundlich isotherm constants (KF) are 3.53

Zhi-gao XU; Yan-ke WU; Jian-dong ZHANG; Li ZHANG; Li-jun WANG

2010-01-01

372

SEM and elemental analysis of composite resins  

SciTech Connect

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

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

1990-12-01

373

Physicochemical characterisation of TMP resin and related model mixtures  

Microsoft Academic Search

A set of model resin mixtures were prepared to simulate Norway spruce thermomechanical pulp (TMP) resin at different conditions, such as in winter or summer, or after lipase and\\/or steryl esterase treatments. The resin samples were analysed on their viscosity, tackiness, wettability and surface energy; properties which may be related to the deposition tendency of wood resin. During production of

Menghua Qin; Tea Hannuksela; Bjarne Holmbom

2003-01-01

374

Incineration of ion-exchange resins in a fluidized bed  

Microsoft Academic Search

Incineration of ion-exchange resins in a fluidized bed was studied on the pilot plant scale. Granular resins were incinerated mostly in the dry form, while powdered resins were incinerated in an ethanol-water mixture. Incineration converts the organic resin into inert oxide material, which can be immobilized for instance with cement. The weight of the ash was 1 to 20% and

M. Valkiainen; M. Nykyri

1982-01-01

375

Reuse system for powdered ion-exchange resins  

Microsoft Academic Search

A reuse system has been developed for powdered ion-exchange resins generated from nuclear power plants in order to reduce their waste volume. The system consists of: 1. crud removal from resins; 2. decomposition of flocks (flocculated resins); 3. resin separation into cation and anion types; 4. regeneration of each type. The most important points in this system are items 2

K. Funabashi; T. Fukasawa; F. Kawamura; H. Yusa; M. Kikuchi; N. Sasaki; T. Yamadera

1986-01-01

376

Identification of selective ion-exchange resin for fluoride sorption  

Microsoft Academic Search

The defluoridation capacity (DC) of a chelating resin, namely Indion FR 10 (IND), and Ceralite IRA 400 (CER), an anion-exchange resin, were compared under various equilibrating conditions for the identification of selective sorbent. The results showed that chelating resin is more selective than an anion-exchange resin for fluoride removal. The fluoride sorption was reasonably explained using Freundlich and Langmuir isotherms.

S. Meenakshi; Natrayasamy Viswanathan

2007-01-01

377

Condensate-polisher resin-leakage quantification and resin-transport studies. [PWR  

SciTech Connect

The objectives of this program were to: (1) determine the extent of resin leakage from current generation condensate polisher systems, both deep bed and powdered resin design, during cut-in, steady-state and flow transient operation, (2) analyze moisture separator drains and other secondary system samples for resin fragments and (3) document the level of organics in the secondary system. Resin leakage samples were obtained from nine-power stations that have either recirculating steam generators or once through steam generators. Secondary system samples were obtained from steam generator feedwater, recirculating steam generator blowdown and moisture separator drains. Analysis included ultraviolet light examination, SEM/EDX, resin quantification and infrared analysis. Data obtained from the various plants were compared and factors affecting resin leakage were summarized.

Stauffer, C.C.; Doss, P.L.

1983-04-01

378

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

379

Interlaminar Fracture Toughness in Resin Matrix Composites.  

National Technical Information Service (NTIS)

This annual report summarizes the objectives, accomplishments and proposed new directions of research on mode II interlaminar fracture in resin matrix composites. A mode II interlaminar fracture specimen, test and analysis method for interpreting results ...

L. W. Rehfield E. A. Armanios A. D. Reddy

1984-01-01

380

Analysis of Commercial Unsaturated Polyester Repair Resins.  

National Technical Information Service (NTIS)

The basic rheological, thermal, and mechanical properties of commercially available repair putties have been determined in this study, as has the composition of these products. These products contain 33% to 40% unsaturated polyester resin, 10% to 20% styr...

C. Greer I. McAninch J. M. Sands K. Andrews S. Bingham

2009-01-01

381

Passifloricins, polyketides ?-pyrones from Passiflora foetida resin  

Microsoft Academic Search

Three polyketides ?-pyrones, named passifloricins, were isolated from Passiflora foetida resin; their structures and relative configurations were assigned through 2D NMR spectroscopic analyses. These types of compounds were not detected in other passion flowers.

Fernando Echeverri; Victor Arango; Winston Quiñones; Fernando Torres; Gustavo Escobar; Yoni Rosero; Rosendo Archbold

2001-01-01

382

Method of Obtaining Phenol-Furfural Resins.  

National Technical Information Service (NTIS)

Invention relates to improvement of method of obtaining phenol-furfural resins, utilized in different branches of national economy as cationites (for purification of waste water from ions of calcium, magnesium, etc., sorption of different metals). Method ...

A. Y. Yuldashev D. R. Tursunova N. U. Rizayev Y. Z. Rakhman-Zade

1990-01-01

383

A Study of Soil Stabilization with Resins.  

National Technical Information Service (NTIS)

An investigation was conducted to determine the availability of new quick-curing resinous materials capable of stabilizing sand and silty clay soils by improving their strength characteristics. The investigation was aimed at overcoming the degrading effec...

H. A. Sultan J. D. Kriegh R. L. Sogge

1971-01-01

384

Mechanical Properties of Degraded PMR-15 Resin.  

National Technical Information Service (NTIS)

Thermo-oxidative aging produces a nonuniform degradation state in PMR-15 resin. A surface layer, usually attributed to oxidative degradation, forms. This surface layer has different properties from the inner material. A set of material tests was designed ...

L. C. Tsuji

2000-01-01

385

Feasibility of vitrifying EPICOR II organic resins  

SciTech Connect

Two laboratory-scale runs have recently been completed to test the feasibility of a single-step incineration/vitrification process for Three Mile Island EPICOR II resins. The process utilizes vitrification equipment, specifically a 15-cm-dia in-can melter, and a specially designed feed technique. Two process tests, each conducted with 1.2 kg of EPICOR II resins loaded with nonradioactive cesium and strontium, showed excellent operational characteristics. Less than 0.8 wt% of the resins were entrained with the gaseous effluents in the second test. Cesium and strontium losses were controlled to 0.71 wt% and less. In addition, all the carbonaceous resins were converted completely to CO/sub 2/ with no detectable CO. Future activities are being directed to longer-term tests in laboratory-scale equipment to determine attainable volume reduction, process rates, and material conformance to processing conditions.

Buelt, J.L.

1981-11-01

386

21 CFR 177.1655 - Polysulfone resins.  

Code of Federal Regulations, 2013 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION...SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS...substances required in the production of such basic resins...solventsâdistilled water, 50 percent...

2013-04-01

387

21 CFR 177.1556 - Polyaryletherketone resins.  

Code of Federal Regulations, 2013 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION...SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS...substances required in the production of such basic resins...solvents: Distilled water, 50 percent...

2013-04-01

388

Effect of cation exchange resin treatment and addition on sugar as anti-caking agent on retention of nutritional and sensory quality of lemon juice powder during storage  

Microsoft Academic Search

Lemon juices clarified with enzymatic treatment with and without cation exchange resin treatment were concentrated to 60o Brix in a vacuum evaporator and converted into powders by foam mat drying technique. Powders obtained from cation exchange\\u000a resin treated juice were better in quality with respect to acidity, glucose, fructose, sugars, and ascorbic acid contents\\u000a as compared to those prepared form

Satish K. Sharma; B. B. L. Kaushal; P. C. Sharma

2011-01-01

389

Resin Glycosides from the Morning Glory Family  

Microsoft Academic Search

\\u000a Resin glycosides are part of a very extensive family of secondary metabolites known as glycolipids or lipo-oligosaccharides\\u000a and are constituents of complex resins (glycoresins) (1) unique to the morning glory family, Convolvulaceae (2). These active\\u000a principles are responsible for the drastic purgative action of all the important Convolvulaceous species used in traditional\\u000a medicine throughout the world since ancient times. Several

Rogelio Pereda-Miranda; Daniel Rosas-Ramírez; Jhon Castañeda-Gómez

2010-01-01

390

Phenol Formaldehyde Resin Modification with Lignin  

Microsoft Academic Search

Lignin (poly?phenylpropane units) was precipitated from waste black liquor produced by paper manufacture from rice straw. The use of this lignin as partial substitution of phenol in phenol formaldehyde resin is investigated. The effect of different variables [e.g., lignin concentration, ratio of formaldehyde to phenol lignin (phenol + lignin), temperature, and polymerization time on the properties of the produced resin is studied].

2003-01-01

391

Nano composite from coal modified novolac resin  

SciTech Connect

Coal-modified novolac/clay nanocomposites were synthesized using clay as reinforcing materials. It was found that coal-modified novolac resin based silica nano-composites showed improved tensile strength compared to that of neat novolac resin. The structure of the nanocomposites was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Scanning electron microscopy (SEM) studies have also been undertaken to see the morphology of the nanocomposites prepared. The results obtained are being reported.

Ahmaruzzaman, M.; Sharma, D.K. [Industrial Technology Institute, Delhi (India)

2007-07-01

392

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

393

Adsorbed resin phase spectrophotometric determination of nickel  

Microsoft Academic Search

?-Cyclodextrin polymer (?-CDP) adsorbed resin phase spectrophotometry with 1-(2-pyridylazo)-2-naphthol (PAN) has been developed for the determination of nickel at the ?g level in human hair and Auricularia auricula (a kind of edible fungi). Iron, manganese, copper, zinc, chromium and cobalt which form colored species with PAN in the resin phase, can be completely masked with the masking solution composed of

Rong Li; Zi-Tao Jiang; Lu-Yuan Mao; Han-Xi Shen

1998-01-01

394

[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

395

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

396

Improvement of drug loading onto ion exchange resin by cyclodextrin inclusion complex.  

PubMed

Context: Ion exchange resins have ability to exchange their counter ions for ionized drug in the surrounding medium, yielding "drug resin complex." Cyclodextrin can be applied for enhancement of drug solubility and stability. Objective: Cyclodextrin inclusion complex of poorly water-soluble NSAIDs, i.e. meloxicam and piroxicam, was characterized and its novel application for improving drug loading onto an anionic exchange resin, i.e. Dowex(®) 1×2, was investigated. Methods: ?-cyclodextrin (?-CD) and hydroxypropyl ?-cyclodextrin (HP-?-CD) were used for the preparation of inclusion complex with drugs in solution state at various pH. The inclusion complex was characterized by phase solubility, continuous variation, spectroscopic and electrochemistry methods. Then, the drug with and without cyclodextrin were equilibrated with resin at 1:1 and 1:2 weight ratio of drug and resin. Results and discussion: Solubility of the drugs was found to increase with increasing cyclodextrin concentration and pH. The increased solubility was explained predominantly due to the formation of inclusion complex at low pH and the increased ionization of drug at high pH. According to characterization studies, the inclusion complex was successfully formed with a 1:1 stoichiometry. The presence of cyclodextrin in the loading solution resulted in the improvement of drug loading onto resin. Conclusions: Enhancing drug loading onto ion-exchange resin via the formation of cyclodextrin inclusion complex is usable in the development of ion-exchange based drug delivery systems, which will beneficially reduce the use of harmful acidic or basic and organic chemicals. PMID:23078590

Samprasit, Wipada; Rojanarata, Theerasak; Akkaramongkolporn, Prasert; Ngawhirunpat, Tanasait; Sila-On, Warisada; Opanasopit, Praneet

2012-10-19

397

A medicated polycarboxylate cement to prevent complications in composite resin therapy  

SciTech Connect

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

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

1990-01-01

398

Triterpenes from Protium hebetatum resin.  

PubMed

Three olean (beta-amyrenone, beta-amyrin and maniladiol), three ursane (alpha-amyrinone, alpha-amyrin and breine) and four tirucallane (3-oxotirucalla-8,24-dien-21-6ic acid, 3alpha-hydroxytirucalla-8,24-dien-21-oic acid, 3alpha-acetoxytirucalla-8,24-dien-21-oic acid and 3alpha-hydroxytirucalla-7,24-dien-21-oic acid) triterpenes were isolated from the oleoresin of Protium hebetatum Daly. The structures were established mainly by 13C, 1D and 2D NMR spectroscopic analysis. The isolation of 3alpha-hydroxytirucalla-8,24-dien-21-oic acid permitted correction of the chemical shift assignments of some of its carbon atoms. PMID:20839613

Marques, Delcio Dias; Graebner, Ilmar Bernardo; de Lemos, Telma Leda Gomes; Machado, Luciana Lucas; Assunção, Jõao Carlos Costa; Monte, Francisco José Queiroz

2010-08-01

399

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

SciTech Connect

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

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

1987-05-01

400

[Adhesion mechanism of MMA/TBBO resin containing 4-META to decalcified dentin].  

PubMed

As a model experiment to understand the mechanism of adhesion of the 4-META-MMA/TBBO resin to dentin, 4-META-MMA/TBBO was polymerized in the presence of decalcified dentin sheet treated with citric acid (CA) aqueous solution containing ferric chloride (FC). Curing time of MMA/TBBO resin was reduced by the addition of 4-META to MMA. Addition of 4-META increased molecular weight of PMMA. PMMA polymerized inside the decalcified dentin sheet was insoluble in acetone. PMMA obtained from the monomer liquid used in commercial Super-Bond C & B was all insoluble and no soluble fraction was obtained. These results suggested that 4-META accelerated polymerization of MMA-TBBO resin in the presence of ferric ion and was effective to enhance molecular weight of PMMA. These effects seemed to be related to high bond strength of Super-Bond with dentin. PMID:2135553

Akimoto, T; Kadoma, Y; Imai, Y

1990-11-01

401

Phosphorus recovery as struvite from eutropic waters by XDA-7 resin.  

PubMed

Phosphorus releases into aquatic environment and its subsequent contribution to eutrophication have resulted in a widespread global pollution issue. However, phosphorus is a non-renewable source. The potential supplies of phosphorus are decreasing worldwide. Therefore, removal and recovery of phosphorus from the eutropic waters is important, emergent and necessary. In this research, experiments for recovering phosphate from eutropic waters by anion exchange combined with struvite precipitation were conducted. The results indicated that the prepared XDA-7 resin was an effective adsorbent for phosphate. The adsorption isotherm of XDA-7 resin was found to be a modified Freundlich type. The maximum phosphate adsorption (20.9 mg/g) occurred in the pH range of 6.0-8.0. Phosphate adsorbed on the XDA-7 resin was effectively desorbed with 8% NaCl solution, and the resin was able to be regenerated with 3% NaClO and 4% NaOH solutions. Phosphate desorbed from the resin was recovered as magnesium ammonium phosphate (struvite). The obtained struvite was analyzed by acid dissolution method, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The struvite precipitate was found to be 75.8% in purity, a high-value fertilizer. PMID:22643401

Li, Huanwen; Ye, Zhiping; Lin, Ying; Wang, Fengying

2012-01-01

402

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

403

Influence of oxygen-inhibited layer on dentin bond strength of chemical-cured resin composite.  

PubMed

This study evaluated the influence of an oxygen-inhibited layer on the surface free energies of three single-step self-etch adhesives and on the bond strength of chemical-cured resin. Adhesives were applied to bovine dentin and light irradiated, and the oxygen-inhibited layer was either retained or removed. Surface free energies were determined by measuring the contact angles of test liquids placed on the cured adhesives. Dentin bond strengths of chemical-cured resin with and without the oxygen-inhibited layer were measured. Ultrastructural observation of the restorative-dentin interface was made by scanning electron microscopy. For all surfaces, values of the estimated surface tension component, Lifshitz-Van der Waals force (?S (LW) ), were relatively constant. Values for the Lewis acid (?S (+) ) component increased slightly when the oxygen-inhibited layer was removed, whereas those of the Lewis base (?S (-) ) component decreased significantly. The bond strength of the chemical-cured resin composite was significantly higher in specimens without an oxygen-inhibited layer (7.6-8.0 MPa) than in those with an oxygen-inhibited layer (4.8-5.2 MPa). Small gaps between adhesive and resin composite were found for the group with an oxygen-inhibited layer. These results indicate that the absence of an oxygen-inhibited layer in single-step self-etch adhesives promotes higher dentin bond strength of the chemical-cured resin. PMID:24028599

Yamaji, Ayumi; Koga, Kensaku; Tsujimoto, Akimasa; Shimizu, Yusuke; Tsubota, Keishi; Takamizawa, Toshiki; Miyazaki, Masashi

2013-08-17

404

Use of NIR spectroscopy in the production of modified industrial resins.  

PubMed

Natural resins are scarcely used, but after appropriate modification processes they acquire characteristics of viscosity, point of softening, stability, etc. that facilitate their application in fields such as paintings, varnishes, cosmetic, etc. The complexity of resins makes it very difficult to monitor the reactions involved in their modification, the extent of which is usually determined via more experimentally accessible parameters. However, the methods typically used to determine such parameters are slow and produce environmentally unfriendly waste. In this work, we assessed the potential of NIR spectroscopy, as an alternative to the traditional analytical methods, for monitoring the industrial processes involved in the production of modified resins. To this end, we developed PLS calibration models that were used to quantify physical (viscosity and cloud point) and chemical parameters (acid and hydroxyl numbers), with a view to characterize the evolution of the resins during the reaction that take place throughout the fabrication process. Samples were withdrawn at different times stages of the process for analysis with the proposed quantitation models; the data thus obtained were compared with those provided by reference methods. Based on the results, NIR spectroscopy is an effective choice for the accurate, expeditious monitoring of industrial resin modification processes. PMID:19071454

Blanco, M; Villaescusa, V

2006-08-22

405

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

PubMed Central

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

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

2009-01-01

406

Aging and yellowing of triterpenoid resin varnishes – Influence of aging conditions and resin composition  

Microsoft Academic Search

The aging of natural triterpenoid resins used as varnishes on paintings is still insufficiently understood. Although progress has been made, questions concerning the aging pathways in light vs. darkness, or the correlation of oxidation with yellowing, remain open. The influence of aging conditions, primarily the amount of light, but also resin composition, on the aging process were investigated. The aging

Patrick Dietemann; Catherine Higgitt; Moritz Kälin; Michael J. Edelmann; Richard Knochenmuss; Renato Zenobi

2009-01-01

407

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

408

[Classification and several mechanical properties of core composite resins].  

PubMed

According to the classification proposed by Hosoda, six core resins could be divided into two categories on the basis of the elemental composition and size distribution of filler particles by SEM observation and EDX analysis. Furthermore, several mechanical properties of the resins were determined. The following facts were found: Bell Feel Core, Clearfil Core, Clearfil PhotoCore, Core Max, and Core Max II resins were classified as a semihybrid resin, and Microrest Core resin as a hybrid type resin. The elements detected in the resins by the EDX were Si, Zr, Al, Ba and La. The mechanical properties of the resins were shown to be highly stable at one day or one week after curing. The mechanical properties of the resins suggest that the subsequent crown preparation and impression taking should be postponed until the next appointment. PMID:2135512

Yamada, T; Hosoda, H; Tsurugai, T

1990-03-01

409

The effect of peptide length on the cleavage kinetics of 2-chlorotrityl resin-bound ethers.  

PubMed

Different characteristics of cleavage kinetics of resin-bound amino alcohols and their peptide derivatives were observed in acid containing protic and aprotic solvent mixtures. The hydrolysis reactions are hindered by steric crowding around the cleaving C--O bond and accelerated by the special solvation effect of CF(3)CH(2)OH on the peptide chain as well as the increase of the strength and concentration of the acid. In trifluoroacetic acid containing mixtures, trifluoroacetylation of the peptide alcohols was detected. The appearance of O-trifluoroacetyl serine and threonine derivatives is detected in cleavage mixtures containing trifluoroacetic acid in anhydrous solvent. PMID:16485312

Kocsis, László; Ruff, Ferenc; Orosz, György

2006-06-01

410

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

NASA Astrophysics Data System (ADS)

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

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

2007-04-01

411

Anion-exchange resin-based desulfurization process  

SciTech Connect

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

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

1991-01-01

412

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.

Piver, W T

1976-01-01

413

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

414

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

Federal Register 2010, 2011, 2012, 2013

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

2011-03-09

415

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

Federal Register 2010, 2011, 2012, 2013

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

2011-07-18

416

Posterior composite resin restorations: operative innovations.  

PubMed

The adhesive revolution is alleviating reservations regarding posterior composite resin restorations, established by past experience with outdated materials and techniques. Improved materials, instrumentation, and placement techniques have enhanced the performance of current formulations of posterior composite resins over their predecessors. However, it is a clinician's operative skill that ultimately determines the quality of a restorative option. The learning objective of this article is to share the author's experience in attaining adhesive excellence with posterior tooth-colored restorations as well as aesthetic anatomic form, minimal postoperative sensitivity, and a bond which can weather the true test of success-durability. Optimal applications, dental dam requirement, importance of the first increment of composite resin, restitution of occlusal morphology, and the clinical application are discussed. PMID:9242131

Liebenberg, W H

1996-10-01

417

Corrosion of resin-bonded orthodontic brackets.  

PubMed

The objective was to identify the nature and origin of indelible black and green stains found in enamel after the removal of bonded orthodontic brackets. Several brackets were examined by scanning electron microscopy and energy-dispersive x-ray analysis. Irrespective of the type of bracket or resin, morphologic evidence of corrosion activity was found. Brackets were pitted, and in some cases large amounts of metal were missing. Cracks were found in the resin which led to sites of destruction in which structures resembling microorganisms were also found. X-ray analysis showed the presence of chromium, nickel, iron, and chlorine in significant amounts in the bonding, discolored resin. It was concluded that the cracks were favoring crevice corrosion. In the presence of organisms and a lowered pH, together with a chloride environment and an oxygen gradient, conditions conducive to corrosion are established. PMID:6758601

Gwinnett, A J

1982-06-01

418

The Role of Lactic Acid Adsorption by Ion Exchange Chromatography  

Microsoft Academic Search

BackgroundThe polyacrylic resin Amberlite IRA-67 is a promising adsorbent for lactic acid extraction from aqueous solution, but little systematic research has been devoted to the separation efficiency of lactic acid under different operating conditions.Methodology\\/Principal FindingsIn this paper, we investigated the effects of temperature, resin dose and lactic acid loading concentration on the adsorption of lactic acid by Amberlite IRA-67 in

Qiang Gao; Fabao Liu; Tongcun Zhang; Jian Zhang; Shiru Jia; Changyan Yu; Kunyu Jiang; Nianfa Gao; Richard C. Willson

2010-01-01

419

Masking the taste of the conditioned taste aversion agent levamisole using an ion-exchange resin, for practical application in wildlife management.  

PubMed

For a conditioned taste aversion (CTA) agent to be successful in wildlife management applications, the compound must not be detectable by the animal. Levamisole is an effective CTA agent when administered by oral intubation, but it is readily detected by a number of species when mixed directly in food. This paper describes the development of an ion-exchange resin complex (resinate) to mask the taste of levamisole. Two different resins were evaluated, Amberlite IRP-64 and Amberlite IRP-69, and release studies indicated that the resinate formed using IRP-64 resin would be most suitable for use in wildlife management. Although it contained a relatively low loading of levamisole (77 g kg(-1)), the results indicated that the IRP-64 resinate should be stable in the mouth and release the levamisole quickly in the acid environment of the stomach (93% of levamisole was released into 0.1 M HCl in 5 min). In a bioassay using laboratory rats (Rattus norvegicus Berk), we showed that the taste of levamisole was successfully masked in a biscuit bait using the IRP-64 resinate and that a CTA was generated to untreated bait. The use of ion-exchange resins is a new approach in the taste-masking of CTA agents and could be applied to other wildlife management applications. PMID:16217732

Cotterill, Jane V; Massei, Giovanna; Cowan, David P

2006-02-01

420

Taste masking of Etoricoxib by using ion-exchange resin.  

PubMed

The present study was carried out in order to mask the bitter taste of the Etoricoxib by complexation with cation-exchange resin, Indion 204. The drug resin complexes (DRC) were prepared by batch process and efficient drug loading was obtained by using inactivated form of resin in the drug-resin ratio 1:3.3 with 30 min swelling time of resin in 25 mL of water with 5 min stirring time. Drug-resin complexes were characterized for dissolution studies and spectral studies. Drug release from drug-resin complex in salivary pH was insufficient to impart bitter taste. Volunteers rated the drug resin complex as tasteless and agreeable. PMID:19845450

Patra, Sradhanjali; Samantaray, Rakesh; Pattnaik, Saswat; Barik, B B

421

Analytical Vacuum-Assisted Resin Transfer Molding (VARTM) Flow Model.  

National Technical Information Service (NTIS)

A closed form solution for the flow of resin in the vacuum-assisted resin transfer molding (VARTM) process is used extensively for affordable manufacturing of large composite structures. During VARTM processing, a highly permeable distribution medium is i...

B. K. Fink K. Hsiao R. Mathur J. W. Gillespie S. G. Advani

2000-01-01

422

21 CFR 175.270 - Poly(vinyl fluoride) resins.  

Code of Federal Regulations, 2010 CFR

...federal_register/code_of_federal_regulations/ibr_locations.html. (1) Solvent. N,N- Dimethylacetamide, technical grade. (2) Solution. Powdered resin and solvent are heated at 120 °C until the resin is...

2009-04-01

423

Commercial Ion Exchange Resin Vitrification in Borosilicate Glass.  

National Technical Information Service (NTIS)

Bench-scale studies were performed to determine the feasibility of vitrification treatment of six resins representative of those used in the commercial nuclear industry. Each resin was successfully immobilized using the same proprietary borosilicate glass...

C. A. Cicero-Herman P. Workman K. Poole D. Erich J. Harden

1998-01-01

424

Significant Properties of Epoxy Resins as Matrices in Graphite Composites.  

National Technical Information Service (NTIS)

The objective of the work being reported was to determine experimentally what properties of the matrix resins most significantly affected the mechanical properties of the unidirectional graphite fiber/epoxy resin composites evaluated. Five different epoxy...

W. Mahieu J. C. Weidner R. J. Kuhbander

1971-01-01

425

21 CFR 872.3300 - Hydrophilic resin coating for dentures.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

426

21 CFR 872.3820 - Root canal filling resin.  

Code of Federal Regulations, 2013 CFR

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

2013-04-01

427

21 CFR 177.2420 - Polyester resins, cross-linked.  

Code of Federal Regulations, 2010 CFR

... Asbestos Glass fiber Polyester fiber produced by the... (c) The cross-linked polyester resins, with or...In accordance with good manufacturing practice, finished articles containing the cross-linked polyester resins shall be...

2009-04-01

428

21 CFR 177.2420 - Polyester resins, cross-linked.  

Code of Federal Regulations, 2010 CFR

... Asbestos Glass fiber Polyester fiber produced by the... (c) The cross-linked polyester resins, with or...In accordance with good manufacturing practice, finished articles containing the cross-linked polyester resins shall be...

2010-01-01

429

Flammability Characteristics of Some Epoxy Resins and Composites.  

National Technical Information Service (NTIS)

The flammability characteristics of a number of epoxy resin formulations and glass fiber-reinforced epoxy resin composites have been evaluated by thermal analysis, limiting oxygen index/temperature index, flash ignition, and smoke density measurement tech...

D. P. Macaione R. P. Dowling P. R. Bergquist

1983-01-01

430

Intensification of Gold Sorption by Anion Exchange Resins  

Microsoft Academic Search

Gold extraction technology based on anion exchange resins with mixed basicity, commonly used in former soviet countries, includes a complicated and expensive process of resin regeneration and gold stripping by thiocarbamide solution. Satisfactory sorption properties of weak base anion exchange resin at pH 6–8 and low cost of metal stripping by sodium hydroxide solution have aroused considerable interest in these

V. V. AMBAROV; N. O. NIZHEGORODTSEVS

1995-01-01

431

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Mineral reinforced nylon resins. 177.2355 Section 177.2355 Food...Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of...

2009-04-01

432

21 CFR 177.2355 - Mineral reinforced nylon resins.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Mineral reinforced nylon resins. 177.2355 Section 177.2355 Food...Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of...

2010-01-01

433

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

434

Color stability of restorative resins under accelerated aging.  

PubMed

The color stability of seven commercial composite resins, an unfilled resin, and three glazes was studied under conditions of accelerated aging by reflection spectrophotometry and visually with Munsell color tabs. After aging for 900 hours, most of the resins had lower values of luminous reflectance and excitation purity and higher values of dominant wavelength and contrast ratio compared to values at baseline. PMID:281342

Powers, J M; Dennison, J B; Koran, A

435

49 CFR 173.165 - Polyester resin kits.  

Code of Federal Regulations, 2011 CFR

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

2012-10-01

436

Mathematical Analysis of Resin Flow through Fibrous Porous Media  

Microsoft Academic Search

Resin flow through fiber preforms was analyzed mathematically. Closed form solutions for fiber volume fraction distribution and pressure field during resin infusion into fiber preforms were suggested, and a new effective permeability was defined. The effect of preform compressibility on the fiber volume fraction and pressure distributions in resin-saturated region was investigated analytically. The findings show that the compaction behavior

Young Seok Song

2006-01-01

437

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

438

Epoxy resin developments for large superconducting magnets impregnation  

Microsoft Academic Search

The future detectors ATLAS and CMS of the Large Hadron Collider at CERN will use two huge superconducting magnets. Both are now under design, and their electrical insulation could be realized using epoxy resin and a wet impregnation technique. Because of their large dimensions, and the indirect cooling of the superconductor, the strengths of the resin and of the resin\\/conductor

J. M Rey; B Gallet; F Kircher; J. C Lottin

1998-01-01

439

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2010 CFR

...Drugs 3 2009-04-01 2009-04-01 false Ion-exchange resins. 173.25 Section 173.25...Polymer Adjuvants for Food Treatment § 173.25 Ion-exchange resins. Ion-exchange resins may be safely used in the...

2009-04-01

440

Thermokinetic behavior of powdered phenol-formaldehyde (PPF) resins  

Microsoft Academic Search

This study was conducted to investigate thermokinetic behavior of powdered phenol-formaldehyde (PPF) resins used for the production of wood-based panel products. Both fusion diameter and stroke cure time of the PPF resins were measured to characterize flow properties and reactivity of PPF resins. In addition, differential scanning calorimetry (DSC) was also used to obtain apparent glass transition temperature (Tg) and

Byung-Dae Park; Xiang-Ming Wang

2005-01-01

441

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2010 CFR

...purpose of this section, the phenolic resins are those produced...employed in the production of the phenolic resins or added thereto to...extractives limitations: (1) Total extractives not to exceed...molded articles containing the phenolic resins shall be...

2010-01-01

442

21 CFR 177.2410 - Phenolic resins in molded articles.  

Code of Federal Regulations, 2010 CFR

...purpose of this section, the phenolic resins are those produced...employed in the production of the phenolic resins or added thereto to...extractives limitations: (1) Total extractives not to exceed...molded articles containing the phenolic resins shall be...

2009-04-01

443

Stability and demulsification of emulsions stabilized by asphaltenes or resins  

Microsoft Academic Search

Experimental data are presented to show the influence of asphaltenes and resins on the stability and demulsification of emulsions. It was found that emulsion stability was related to the concentrations of the asphaltene and resin in the crude oil, and the state of dispersion of the asphaltenes and resins (molecular vs colloidal) was critical to the strength or rigidity of

Lixin Xia; Shiwei Lu; Guoying Cao

2004-01-01

444

21 CFR 173.25 - Ion-exchange resins.  

Code of Federal Regulations, 2010 CFR

... 3 2010-01-01 2009-04-01 true Ion-exchange resins. 173.25 Section 173.25 Food...Polymer Adjuvants for Food Treatment § 173.25 Ion-exchange resins. Ion-exchange resins may be safely used in the treatment...

2010-01-01

445

Novel Uncured Epoxy Resin\\/CaCO3 Nanocomposites  

Microsoft Academic Search

In this paper, we synthesized epoxy resin\\/CaCO3 nanocomposites through in-situ and inclusion polymerization, and the nanoparticles were well dispersed in the resin matrix observed by SEM. The effects of the nanoparticles on the properties of epoxy resin are discussed.

Haojie Yu; Li Wang; Quan Shi; Zhenrong Zhao; Guohua Jiang

2006-01-01

446

RESIN METABOLISM IN THE SAPWOOD OF PINUS RADIATA  

Microsoft Academic Search

Carbon-14 produced in nuclear explosions was used as a tracer to examine ; resin metabolism in Pinus radiata. Annual rings of trees were ground and the ; resin extracted. The C¹²: C¹³ and C¹⁴ ratio of each sample was ; determined. Results indicate that all the resin activity is considerably lower ; than that of the atmosphere at the time

A. T. Wilson; J. M. Gumbley; D. J. Spedding

1963-01-01

447

Shear and tensile bond testing for resin cement evaluation  

Microsoft Academic Search

Objectives. The aim of this study was to compare the tensile and shear bond strengths of one experimental and four commercially available resin cements following the ISO document TR 110405 for bond measurement.Methods. Tensile and shear bond tests were performed using bovine enamel and dentin as the tooth substrate with each of the resin cements. Resin composite rods were cemented

Yuichi Kitasako; Michael F. Burrow; Toru Nikaido; Naoko Harada; Shigehisa Inokoshi; Toshimoto Yamada; Toshio Takatsu

1995-01-01

448

Urea–formaldehyde (UF) adhesive resins for wood  

Microsoft Academic Search

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

M. Dunky

1998-01-01

449

Effect of polysulfonate resins and direct compression fillers on multiple-unit sustained-release dextromethorphan resinate tablets  

Microsoft Academic Search

The purpose of this work was to investigate the effect of different polysulfonate resins and direct compression fillers on\\u000a physical properties of multiple-unit sustained-release dextromethorphan (DMP) tablets. DMP resinates were formed by a complexation\\u000a of DMP and strong cation exchange resins, Dowex 50 W and Amberlite IRP69. The tablets consisted of the DMP resinates and direct\\u000a compression fillers, such as

Thaned Pongjanyakul; Aroonsri Priprem; Padungkwan Chitropas; Satit Puttipipatkhachorn

2005-01-01

450

The Physical Mechanisms Responsible for the Weathering of Epoxy Resins and GFR Epoxy Resins.  

National Technical Information Service (NTIS)

Experiments are described where the cylindrically symmetric fields associated with the fibre/resin interface are explored by examination in the optical microscope. The patterns of birefringence show how the difference of the principal stresses vary with d...

C. Alexandre T. W. Turner K. H. G. Ashbee

1979-01-01

451

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.

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

2009-01-01

452

Thermal Stability of Ion-Exchange Resins.  

National Technical Information Service (NTIS)

The action of heat, radiation and oxidants on carbon chain polymers, such as ion-exchange resins, often cause irreversible chemical changes in macro molecules. These changes can be e g the rupture of the carbon-carbon single or double bond, and/or the deg...

J. P. Aittola J. Chyssler H. Ringberg

1982-01-01

453

Basic Studies on Recycling of ABS Resin  

Microsoft Academic Search

With recent development of the petrochemical industry, plastic products have made our society more convenient. However, the disposal of these convenience products has become a serious threat to the environment. Therefore, research on recycling plastic wastes is necessary now more than ever. This paper is a basic study of recycling technology for ABS (acryionitile-butadienestyrene) resin. We tried to show the

Jin Kuk Kim; Chang K. Kang

1995-01-01

454

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

455

Modification of Unsaturated Polyester Resin Using Elastomers  

Microsoft Academic Search

Unsaturated polyester resin is widely used in the fiber reinforced plastic industry It suffers from lack of toughness, which makes it susceptible to breakage in the absence of reinforcement. This problem can be solved, at least partly, by the incorporation of elastomers. In this study a simple technique of dissolving various masticated elastomers in styrene and subsequent solution blending with

C. Mary Lubi; K. Ravi; Abdeen Ahammed; Eby Thomas Thachil

2000-01-01

456

Ternary resin-bound Dynamic Combinatorial Chemistry.  

PubMed

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

2012-01-13

457

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

458

The Reactions of Polyamides with Epoxy Resins.  

National Technical Information Service (NTIS)

It was found that the interaction of epoxy resins based on bis-phenol A with polyamides in various solvents leads to the formation of a soluble block copolymer. In the absence of a solvent, a block copolymer of a three-dimensional structure is formed. The...

M. M. Tarnorutskii S. R. Rafikov B. A. Zhubanov T. N. Koryanova

1968-01-01

459

Application of curable resin-coated proppants  

SciTech Connect

This paper reports on a laboratory investigation of the interactions between fracturing fluids and resin-coated proppants (RCP's) which revealed (among other conclusions) that RCP's are incompatible with oxidizing breakers. Areas covered included RCP effect on fluid rheology, fluid relationship to RCP strength, theoretical study of required RCP strengths to prevent flowback, and experimental measurement to establish minimum strength.

Norman, L.R.; Terracina, J.M.; McCabe, M.A.; Nguyen, P.D. (Halliburton Services, Duncan, OK (United States))

1992-11-01

460

Micro-tensile bond testing of resin cements to dentin and an indirect resin composite  

Microsoft Academic Search

Objectives: Micro-tensile bond strength (?TBS) evaluation and fractographic analysis were used to compare four resin cement systems (AC: All-Bond 2\\/Choice; RX: Single Bond\\/RelyX ARC; SB: Super-Bond C&B; and PF: Panavia F) in indirect composite\\/dentin adhesive joints.Methods: Flat dentin surfaces were created on extracted human third molars. The resin cements were used according to the manufacturers' instructions for bonding silanized composite

Yiu-Fai Mak; Shirley C. N Lai; Gary S. P Cheung; Alex W. K Chan; Franklin R Tay; David H Pashley

2002-01-01

461

Unrestricted linear dimensional changes of two hard chairside reline resins and one heat-curing acrylic resin  

Microsoft Academic Search

The selection and use of hard chairside reline resins must be made with regard to dimensional stability, which will influence the accuracy of fit of the denture base. This study compared the dimensional change of two hard chairside reline resins (Duraliner II and Kooliner) and one heat-curing denture base resin (Lucitone 550). A stainless steel mold with reference dimensions (AB,

Ana Lucia Machado Cucci; Eunice Teresinha Giampaolo; Paulo Leonardi; Carlos Eduardo Vergani

1996-01-01

462

Effect of Resin System Parameters on Resin Transfer Molding of Vinyl Ester Based Composites—A Statistically Designed Study  

Microsoft Academic Search

Although the area of composites has advanced significantly over the past three decades, there is still a lack of understanding as to the coupling between materials and processing variables, especially as related to the use of resin systems in emerging processes such as resin transfer molding (RTM). As materials are tailored through the use of additives to resin systems, intricate

Vistasp M. Karbhari; Gaurav Chhabra

1995-01-01

463

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4â²-isopropylidenediphenol-epichlorohydrin epoxy resins.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Xylene-formaldehyde resins condensed with 4,4â...of Coatings § 175.380 Xylene-formaldehyde resins condensed with 4,4â²-isopropylidenediphenol-epichlorohydrin...produced by the condensation of xylene-formaldehyde resin and...

2013-04-01

464

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

465

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

466

Surface tension of solutions of low-molecular epoxy resins in monoglycidyl ether on the interface with air and production of filled epoxy compositions  

Microsoft Academic Search

The surface tension of solutions of epoxydiane resin (M\\u000a \\u000a n\\u000a ?400) in versatic acid monoglycidyl ether (Cardura) at the interface with air in the range of concentrations c = 5–60% in the presence of non-ionic surfactants was studied. The effect of concentration of epoxydiane resin in solution\\u000a on the rate of dispersion of pigment particles (filler) was revealed. The structural

A. N. Krasovskii; S. A. Lopato; M. G. Potashev

2009-01-01

467

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

468

Importance of sample pH on recovery of mutagenicity from drinking water by XAD resins  

Microsoft Academic Search

Sample pH and the presence of a chlorine residual were evaluated for their effects of the recovery of mutagenicity in drinking water following concentration by XAD resins. The levels of mutagenicity in the pH 2 concentrates were 7-8-fold higher than those of the pH 8 concentrates, suggesting that acidic compounds accounted for the majority of the mutagenicity. The presence of

H. Paul Ringhand; John R. Meier; Frederick C. Kopfler; Kathy M. Schenck; William H. Kaylor; Donald E. Mitchell

1987-01-01

469

Effect of chemical modification of lignin on the gluebond performance of lignin-phenolic resins  

Microsoft Academic Search

Lignin obtained from eucalyptus wood by acetic acid pulping was methylolated or phenolated and used to prepare lignin-phenol-formaldehyde resins. The amount of formaldehyde consumed in the methylolation reaction, and supporting comparison of pre- and post-methylolation 1H and 13C NMR spectra, showed the reactivity of the crude acetosolv lignin with formaldehyde to be relatively high. Pine and eucalyptus plywood boards manufactured

G. Vázquez; J. González; S. Freire; G. Antorrena

1997-01-01

470

Migration of melamine and formaldehyde from tableware made of melamine resin  

Microsoft Academic Search

Migration of melamine and formaldehyde into food?simulating solvents from cups made of melamine resin was studied under various conditions. Little migration of melamine was observed in any unused cups kept at 60°C for 30 min, room temperature (26°C) for 1 h or cooled at—20°C for several days. Migration of both compounds was strongly affected by heating and acidity. The highest

Hajimu Ishiwata; Takiko Inoue; Akio Tanimura

1986-01-01

471

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

Microsoft Academic Search

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

Langton

1998-01-01

472

Engineering Plastics from Lignin. VIII. Phenolic Resin Prepolymer Synthesis and Analysis  

Microsoft Academic Search

A sequential derivatization of lignin with formaldehyde and phenol was investigated as a means of enhancing lignin's reactivity in phenol-formaldehyde resins. Kraft lignin (KL) and two novel biocon version lignins, steam explosion (SEL) and acid (H2SO4) hydrolysis lignin (AHL), were chemically modified by sequential reaction with formaldehyde and phenol. The results with regard to the chemical structure of the phenolic

Peter C. Muller; Wolfgang G. Glassert

1984-01-01

473

Resin Tag Length of One-Step and Self-Etching Adhesives Bonded to Unground Enamel  

Microsoft Academic Search

Length of resin tags yielded by utilization of an one-step conventional adhesive system and self-etching adhesive system on unground enamel was observed. In study Groups I and III, the enamel surface was etched for 60 seconds with 35% phosphoric acid gel and adhesive systems PQ1 (Ultradent Products, Inc) and Adper Prompt L Pop (3M\\/ESPE) were applied. Adper Prompt L Pop

Renato Herman Sundfeld; Carlos Henrique de Oliveira; Adriana Maria Jorge Dal'acqua da Silva; André Luiz Fraga Briso; Maria Lúcia Marçal Ma Sundfeld

2005-01-01

474

Binary Adsorption in a Fixed-Bed Column Packed with an Ion-Exchange Resin  

Microsoft Academic Search

A mathematical model was adopted to analyze a binary fixed-bed adsorption column packed with an ion-exchange resin. Two pairs of organic compounds, o-cresol-benzoic acid and p-chlorophenol-p-nitrophenol, were employed as the adsorbates. A modified Langmuir isotherm with interaction factors ?i was found suitable for representing the adsorption equilibrium. Scale-up of the binary adsorption column with respect to column length was effective

Run-Tun Huang; Teh-Liang Chen; Hung-Shan Weng

1995-01-01

475

Effects of Nd: YAG laser irradiation on the adaptation of composite resins to root dentin.  

PubMed

One of the most important goals of the restoration of endodontically treated teeth with a composite resin post system is to achieve good adaptation of the composite material to dentin walls to prevent microleakage apically and coronally. In post core systems, to avoid microleakage between the dentin wall and resin material, laser irradiation may seem to be an alternative therapy for increasing adaptation quality. The aim of this study was to investigate the adaptation of a packable composite resin to lased root canal dentin when it was used as post material. Forty-five freshly extracted human teeth were selected and post spaces were prepared. The teeth were divided into three groups. In group 1 the dentin of the post spaces were etched with 35% phosphoric acid, in group 2 the dentin surfaces were irradiated with an Nd: YAG laser, and in group 3 the dentin surfaces were initially treated with the laser and then etched. The teeth of all groups were obturated with a bonding agent and composite. The groups were divided into two subgroups: a group for the scanning electron microscope (SEM) study and a group for the microleakage study. The lased group showed poor adaptation and more microleakage was detected (p<0.05; variance analysis). The laser beam and acid-etching showed no advantage compared to the acid-etching alone (p>0.05). The Nd: YAG laser irradiation adversely affects adhesion to dentin for using composite resin as a post material and does not constitute an alternative to acid-etching. PMID:16299613

Görgül, Güliz; Kivanç, Bagdagül H; Maden, Murat; Ulusoy, Ozgur Ilke Atasoy; Tinaz, A Cemal

2005-11-15

476

Synthesis and Characterizations of Melamine-Based Epoxy Resins  

PubMed Central

A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I) or by adding a silane derivative (resin II). The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials.

Ricciotti, Laura; Roviello, Giuseppina; Tarallo, Oreste; Borbone, Fabio; Ferone, Claudio; Colangelo, Francesco; Catauro, Michelina; Cioffi, Raffaele

2013-01-01

477

Method for permanently storing radioactive ion exchanger resins  

SciTech Connect

A method is claimed for forming a hardened product containing a radioactive ion exchanger resin in a condition for permanent, noncontaminating storage, by the steps of: providing, before fixing, a mass of such ion exchanger resin saturated in water, the resin being at least one resin selected from the group consisting of spherical resins and powdered resins; mixing the resin mass, with stirring, with a blast furnace cement having a composition which causes it to exhibit slow initial hardening, high sulfate resistance and low hydration heat and with a quantity of additional water equal in weight to 20% to 40% of the weight of the blast furnace cement; and allowing the resulting mixture to harden at room temperature.

Kunze, S.; Eden, G.; Koster, R.

1984-11-20

478

Enzymatic hydrolysis and physical characterization of commercial celluloses and cellulose-based ion-exchange powdered mixed resins  

Microsoft Academic Search

Commercial celluloses (BH20, Epicote, FC+) and their cellulose-containing powdered mixed resins (PMR) were evaluated using en