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1

Synthesis of 18F-labeled phenolphthalein and naphtholphthalein  

PubMed Central

The fluorination of phenolphthalein and naphtholphthalein was performed with diluted fluorine gas under acidic conditions. For both compounds we observed an electrophilic fluorination into ortho position to the hydroxyl group. Through the use of this reaction we synthesized and characterized mono-and difluorinated derivatives of phenolphthalein and naphtholphthalein. The compounds were also prepared in the 18F labeled form, which are usable as a new type of probe for in vivo pH measurement in biological objects using Cerenkov imaging or combination of light absorption and PET.

Kachur, Alexander V.; Popov, Andrey A.; Delikatny, E. James; Karp, Joel S.; Popov, Anatoliy V.

2014-01-01

2

Phenolphthalein-containing laxative use in relation to adenomatous colorectal polyps in three studies.  

PubMed Central

Phenolphthalein, the active ingredient in many laxatives, was recently found to be a carcinogen in animal models. Human data suggest a laxative-colon cancer association, but few data specifically address the effects of phenolthalein-containing laxatives. We examined use of phenolphtalein-containing laxatives in relation to occurrence of adenomatous colorectal polyps in data from three case-control studies. The study conducted in Los Angeles, California (1991-1993), and the two studies conducted in North Carolina (1988-1990 and 1992-1995) altogether included 866 cases and 1,066 controls. The prevalence of using phenolphthalein-containing laxatives at least once a week in the recent past, however, was less than 5% among these subjects. The multivariate-adjusted odds ratios associated with recent use of phenolphthalein-containing laxatives once a week or more were 1.8 -95% confidence interval (CI), 0.5-6.2] in Los Angeles, 1.0 (CI, 0.4-2.2) in North Carolina (1988-1990), and 1.1 (CI, 0.2-5.7) in North Carolina (1992-1995). For use of other types of laxatives, the corresponding odds ratios were 1.3 (CI, 0.9-1.9) in Los Angeles, 1.0 (CI, 0.5-1.7) in North Carolina (1988-1990), and 0.9 (CI, 0.4-1.8) in North Carolina (1992-1995). Although the low prevalence of frequent use made for relatively wide confidence intervals, overall these data suggest that use of phenolphthalein-containing laxatives does not increase risk of adenomatous colorectal polyps. PMID:9370521

Longnecker, M P; Sandler, D P; Haile, R W; Sandler, R S

1997-01-01

3

Phenolphthalein-containing laxative use in relation to adenomatous colorectal polyps in three studies.  

PubMed

Phenolphthalein, the active ingredient in many laxatives, was recently found to be a carcinogen in animal models. Human data suggest a laxative-colon cancer association, but few data specifically address the effects of phenolthalein-containing laxatives. We examined use of phenolphtalein-containing laxatives in relation to occurrence of adenomatous colorectal polyps in data from three case-control studies. The study conducted in Los Angeles, California (1991-1993), and the two studies conducted in North Carolina (1988-1990 and 1992-1995) altogether included 866 cases and 1,066 controls. The prevalence of using phenolphthalein-containing laxatives at least once a week in the recent past, however, was less than 5% among these subjects. The multivariate-adjusted odds ratios associated with recent use of phenolphthalein-containing laxatives once a week or more were 1.8 -95% confidence interval (CI), 0.5-6.2] in Los Angeles, 1.0 (CI, 0.4-2.2) in North Carolina (1988-1990), and 1.1 (CI, 0.2-5.7) in North Carolina (1992-1995). For use of other types of laxatives, the corresponding odds ratios were 1.3 (CI, 0.9-1.9) in Los Angeles, 1.0 (CI, 0.5-1.7) in North Carolina (1988-1990), and 0.9 (CI, 0.4-1.8) in North Carolina (1992-1995). Although the low prevalence of frequent use made for relatively wide confidence intervals, overall these data suggest that use of phenolphthalein-containing laxatives does not increase risk of adenomatous colorectal polyps. PMID:9370521

Longnecker, M P; Sandler, D P; Haile, R W; Sandler, R S

1997-11-01

4

Study of the concentration and separation of cadmium with microcrystalline phenolphthalein modified by crystal violet.  

PubMed

A new method for cadmium separation and concentration with microcrystalline phenolphthalein modified by crystal violet (CV) was developed in the paper. In the presence of potassium iodide (KI) and CV, cadmium are quantitatively absorbed on microcrystalline phenolphthalein in the pH range 1.0-6.0 as the forms of water-insoluble ion-associated complexes (CdI(3)(-)).(CV(+)) and (CdI(4)(2-)).(CV(+))(2). Effect of different parameters such as phenolphthalein amount, stirring time, the concentration of CV and KI, various salts and metal ions was studied in detail. During the present study, a significant enhancement of the extraction of cadmium was observed. Cd(II) can be completely separated from Zn(II), Fe(II), Co(II), Ni(II), Mn(II), Cr(III) and Al(III) in this microcrystalline system and well concentrated without the interference of these metal ions at high level. The possible reactive mechanism of cadmium concentration has been discussed. Analytical results obtained by this new method were very gratifying. PMID:18969688

Li, Quanmin; Ouyang, Ruizhuo; Liu, Guoguang

2004-11-15

5

Cyclodextrin-poly(?-caprolactone) based nanoparticles able to complex phenolphthalein and adamantyl carboxylate  

PubMed Central

Summary A new compound composed of poly(?-caprolactone) and ?-cyclodextrin (?-CD) was synthesized by click chemistry. This compound was used to obtain stable nanoparticles, which have been proven to be able to complex phenolphthalein and adamantyl carboxylate. The nanoparticles are characterized by a distinct morphology, i.e., a hydrophobic core formed by the polyester chain and a shell containing the CD part. Moreover, the formed nanoparticles have been proven to encapsulate umbelliferone in the polyester phase, which may serve as an example for the uptake of a drug. The formed nanoparticles were characterized in terms of sizes and morphology by both DLS and TEM. PMID:24991501

Ailincai, Daniela

2014-01-01

6

Cyclodextrin-poly(?-caprolactone) based nanoparticles able to complex phenolphthalein and adamantyl carboxylate.  

PubMed

A new compound composed of poly(?-caprolactone) and ?-cyclodextrin (?-CD) was synthesized by click chemistry. This compound was used to obtain stable nanoparticles, which have been proven to be able to complex phenolphthalein and adamantyl carboxylate. The nanoparticles are characterized by a distinct morphology, i.e., a hydrophobic core formed by the polyester chain and a shell containing the CD part. Moreover, the formed nanoparticles have been proven to encapsulate umbelliferone in the polyester phase, which may serve as an example for the uptake of a drug. The formed nanoparticles were characterized in terms of sizes and morphology by both DLS and TEM. PMID:24991501

Ailincai, Daniela; Ritter, Helmut

2014-01-01

7

End group functionalization of poly(ethylene glycol) with phenolphthalein: towards star-shaped polymers based on supramolecular interactions  

PubMed Central

Summary The synthesis of a new phenolphthalein azide derivative, which can be easily utilized in polymer analogous reactions, is presented. The subsequent cycloaddition reaction with propargyl-functionalized methoxypoly(ethylene glycol) yielded polymers bearing phenolphthalein as the covalently attached end group. In presence of per-?-cyclodextrin-dipentaerythritol, the formation of stable inclusion complexes was observed, representing an interesting approach towards the formation of star shaped polymers. The decolorization of a basic polymer solution caused by the complexation was of great advantage since this behavior enabled following the complex formation by UV–vis spectroscopy and even the naked eye. PMID:25298793

Fleischmann, Carolin; Wohlk, Hendrik

2014-01-01

8

Critical anomalies of alkaline fading of phenolphthalein in the critical solution of 2-butoxyethanol + water.  

PubMed

We have used three-wavelength UV-spectrophotometry to study the reaction of the alkaline fading of phenolphthalein in the critical solution of 2-butoxyethanol + water. It was found that when the temperature was far away from the critical point, the values of the natural logarithm of the rate constant k and the natural logarithm of the chemical equilibrium K determined in our experiments had good linear relationships with the reciprocal of temperature, which served as the backgrounds and were used for correcting k and K in the critical region. The critical slowing down of the reaction and the critical anomaly of the chemical equilibrium were detected near the critical point. The value of the critical exponent characterizing the slowing down effect of the reaction rate was obtained to be 0.156, which was close to the value 0.11 associated with the heat capacity divergence and agreed with the theoretical prediction. The experimental result also confirmed the theoretical prediction of 0.11 for the critical exponent characterizing the weak divergence of the singularity of the chemical equilibrium. PMID:24329072

Du, Zhongyu; Yin, Handi; Hao, Zhiguo; Zheng, Peizhu; Shen, Weiguo

2013-12-14

9

Toxicology and Carcinogenesis Studies of Phenolphthalein (CAS No. 77-09-8) in F344/N Rats and B6C3F1 Mice (Feed Studies).  

National Technical Information Service (NTIS)

Under the conditions of these 2-year feed studies, there was clear evidence of carcinogenic activity of phenolphthalein in male F344/N rats based on markedly increased incidences of benign pheochromocytomas of the adrenal medulla and of renal tubule adeno...

1996-01-01

10

Spectrometric study of AOT-hydrolysis reaction in water/AOT/isooctane microemulsions using phenolphthalein as a chemical probe.  

PubMed

The kinetics of the alkaline hydrolysis of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in water/AOT/isooctane microemulsions has been studied by monitoring the absorbance change of the phenolphthalein in the system with time. The apparent first-order rate constant k(obs) has been obtained and found to be dependent on both the molar ratio of water to AOT ? and the temperature. The dependences of k(obs) on ? have been analyzed by a pseudophase model which gives the true rate constants k(i) of the AOT-hydrolysis reaction on the interface and the partition coefficients K(wi) for the distribution of OH(-) between aqueous and interface pseudophases at various temperatures; the latter is almost independent of the temperature and ?. The temperature dependences of the reaction rate constants k(obs) and k(i) have been analyzed to obtain enthalpy ?H(?), entropy ?S(?), and energy E(a) of activation, which indicate that the distribution of OH(-) between aqueous and interface pseudophases increases ?S(?) but makes no contribution to E(a) and ?H(?). The influence of the overall concentration of AOT in the system on the rate constant has been examined and found to be negligible. It contradicts with what was reported by García-Río et al. (1) but confirms that the first-order reaction of the AOT-hydrolysis takes place on the surfactant interface. The study of the influence of AOT-hydrolysis on the kinetics of the alkaline fading of crystal violet or phenolphthalein in the water/AOT/isooctane microemulsions suggests that corrections for the AOT-hydrolysis in these reactions are required. PMID:22168828

Mao, Shiyan; Chen, Zhiyun; Fan, Dashuang; An, Xueqin; Shen, Weiguo

2012-01-12

11

Destroyed lung due to aspiration of phenolphthalein.  

PubMed

A 76-year-old female, presented with a recurrent cough and haemoptysis after an aspiration of a 'grain de Valls'. Chest radiography and computed tomography demonstrated an atelectasis of the medial segment of the right middle pulmonary lobe. Bronchoscopy was negative for any malignancy but the onco-PET-scan showed a pathologic hypermetabolic lesion in the right middle lobe. A lobectomy was performed and pathology revealed a 'destroyed lung' with images of foreign body reactions and microabscesses without any sign of malignancy. Postoperatively, clinical improvement with complete resolution of the symptoms was observed. With this case report we demonstrate the irritative and clastogenic characteristics of phenolphtalein, the main active ingredient of the 'grain de Valls'. This case also illustrates an example of a false positive PET-scan. PMID:16315846

De Wulf, M; Ceuppens, H; Gheysens, B; Inderadjaja, N

2005-01-01

12

Kinetics of the Fading of Phenolphthalein in Alkaline Solution.  

ERIC Educational Resources Information Center

Described is an experiment which illustrates pseudo-first-order kinetics in the fading of a common indicator in an alkaline solution. Included are background information, details of materials used, laboratory procedures, and sample results. (CW)

Nicholson, Lois

1989-01-01

13

The Chicago Academy of Science and its Peggy Notebaert Nature Museum http://www.caosclub.org/totalcaos/members/caosho33.html  

E-print Network

large, rubber bands · 1 box of baking soda · 1 gallon of vinegar · 1 red cabbage (or phenolphthalein (phenolphthalein can be used as a substitute for the cabbage juice) 3. Put 4 teaspoon baking soda into plastic bags of topsoil q 2 thermometers q plastic wrap q 2 large, rubber bands q 1 box of baking soda q 1 gallon

Mojzsis, Stephen J.

14

Alerts and Advisories  

MedlinePLUS

... Issues Voluntary Nationwide Recall of Forever Beautiful Bee Pollen Due to Undeclared Sibutramine and Phenolphthalein ( FDA ; 11/ ... Acai Supplements ( FTC ; 06/19/14 ) Some Bee Pollen Weight Loss Products Are a Dangerous Scam ( FDA ; ...

15

The Best Enzyme Investigation Ever? Probably.  

ERIC Educational Resources Information Center

Uses alkaline phosphate to remove the phosphate group from phenolphthalein diphosphate. Discusses problems which include the interference of ambient light and temperature variation. Provides detailed information about the apparatus and the experimental procedure. (ASK)

Cooper, Phil

2000-01-01

16

Visualization of turbulent reacting flow in a microscale nanoprecipitation reactor  

Microsoft Academic Search

A flow visualization technique using the pH sensitive dye phenolphthalein was used to visualize and quantify turbulent reacting mixing in a microscale nanoprecipitation reactor. Phenolphthalein is colorless at pH lower than 8, but turns pink at higher pH, making it useful for visualizing acid-base reactions. Using this dye, turbulent reactive mixing in a confined impinging jets reactor (CIJR) was investigated.

Yanxiang Shi; Somashekar Vishwanat; Michael Olsen; Rodney Fox

2009-01-01

17

"Mud" + "Blood"--A Very Colorful Demonstration.  

ERIC Educational Resources Information Center

Describes a demonstration in which a bloodred-colored solution of hydrogen peroxide, sodium hydroxide, and phenolphthalein indicator is added to a mud-colored solution of potassium permanganate, hydrated manganous chloride, and sulfuric acid. The mixture turns clear when added together. Draws parallels between the demonstration and the Old…

Hambly, Gordon

1998-01-01

18

Preparation of disappearing inks and studying the fading time on different paper surfaces.  

PubMed

Disappearing inks have been used in different fields, but it may be abused in forgery and counterfeiting. This research was conducted on the preparation of disappearing inks using different concentrations of thymolphthalein, phenolphthalein, and their mixture. The prepared inks were applied to different types of handwriting papers. It was found that the handwriting stability increased by increasing thymolphthalein, phenolphthalein, or alkali concentration, but in the case of using 4 mL of 1 normal (N) NaOH, the handwriting stability of phenolphthalein and its mixture inks decreased. Deciphering of the faded handwriting was evaluated by different methods; using optical deciphering, the faded handwriting did not respond to the different light sources. All the faded handwriting was visible when treated with alkaline solution. There was no change in the faded handwriting when heated to 100°C; phenolphthalein and mixture inks containing 0.5 mL of 1 N NaOH became red when only Azhar and Xerox papers were heated to 150°C. PMID:22788417

El-Molla, Mohamed Mabrouk; Shama, Sayed Ahamed; Saeed, Saeed El-Sayed

2013-01-01

19

Initial evaluation tests of General Electric Company 12.0 ampere hour nickel cadmium spacecraft cells with design variables  

NASA Technical Reports Server (NTRS)

All evaluation tests were performed at room ambient pressure and temperature, with discharges at a 2 hour rate. Tests consisted of phenolphthalein leak tests, three capacity tests, an auxiliary electrode test, a charge retention test, an internal short test, a charge efficiency test, overcharge tests, and a pressure versus capacity test. Results of the tests and recommendations for improvements in manufacturing are presented.

Harkness, J. D.

1979-01-01

20

Demonstrating Diffusion  

ERIC Educational Resources Information Center

Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

Foy, Barry G.

1977-01-01

21

Polymerization by phase transfer catalysis  

Microsoft Academic Search

Phenolphthalein polythiocarbonate was obtained by phase transfer catalysis using several catalysts and characterized by inherent viscosity, i.r. spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. From the thermogravimetric curve, the kinetics parameters were determined. Glass transition temperature, thermal decomposition temperature, activation energy, and preexponential factor were lower than those determined for the corresponding polycarbonate.

L. H. Tagle; F. R. Díaz; N. Valdebenito

1987-01-01

22

A RAPID SCREENING METHOD FOR CGTASE-PRODUCING BACTERIA USING DIFFERENT STARCHES AS CARBON SOURCE  

Microsoft Academic Search

Cyclodextrin glycosyltransferases (CGTases) are extracellular bacterial enzymes that generate cyclodextrin from starch. Screening, isolation and characterisation of CGTases are extensively carried out due to its importance in industrial biotechnology. Conventionally, identification of CGTase-producing bacteria involves the use of solid media containing phenolphthalein-methyl orange as indicators by colour changes. The formation of CGTase does not require a specific inducer as the

SURAINI ABD-AZIZ; SAUVAPHAP AI NOI; OSMAN HASSAN

23

ACIDITY AND ALKALINITY IN MINE DRAINAGE: THEORETICAL CONSIDERATIONS1  

Microsoft Academic Search

Acidity, net acidity, and net alkalinity are widely used parameters for the characterization of mine drainage, but these terms are not well defined and are often misunderstood. Incorrect interpretation of acidity, alkalinity, and derivative terms can lead to inadequate treatment design or poor regulatory decisions. We briefly explain derivations of theoretical expressions of three types of alkalinities (caustic, phenolphthalein, and

Carl S. Kirby; Charles A. Cravotta

2004-01-01

24

Net alkalinity and net acidity 1: Theoretical considerations  

Microsoft Academic Search

Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation

Carl S. Kirby; Charles A. Cravotta

2005-01-01

25

Thermoplastic polymers for improved fire safety  

NASA Technical Reports Server (NTRS)

The thermochemical and flammability characteristics of some typical thermoplastic materials currently in use and others being considered for use in aircraft interiors are described. The properties studied included (1) thermomechanical properties such as glass transition and melt temperature, (2) changes in polymer enthalpy by differential scanning calorimetry, (3) thermogravimetric analysis in anaerobic and oxidative environments, (4) oxygen index, (5) smoke evolution, (6) relative toxicity of the volatile products of pyrolysis, and (7) selected physical properties. The generic polymers that were evaluated included: acrylonitrile butadiene styrene, bisphenol A polycarbonate, 9,9 bis (4-hydroxyphenyl) fluorene polycarbonatepoly (dimethyl siloxane) block polymer, phenolphthalein bisphenol A polycarbonate, phenolphthalein polycarbonate, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyaryl sulfone, chlorinated polyvinyl chloride homopolymer, polyvinyl fluoride, and polyvinylidene fluoride. Processing parameters, including molding characteristics of some of the advanced polymers, are described. Test results and relative ranking of some of the flammability, smoke, and toxicity properties are presented.

Kourtides, D. A.; Parker, J. A.; Hilado, C. J.

1976-01-01

26

Sulfonated poly(arylene ether sulfone) RO membranes for high water flux and chlorine resistance  

Microsoft Academic Search

Sulfonated poly(arylene ether sulfone) copolymers containing carboxylic groups (cPES) were successfully prepared by an aromatic substitution polymerization reaction from phenolphthalin (PP), 3,3?-disulfonated-4,4?-dichlorodiphenyl sulfone (SDCDPS), phenolphthalein containing amino group (PPH-NH2) as novel thin film composite (TFC) reverse osmosis (RO) membrane material for high water flux. TFC membranes were fabricated by an interfacial polymerization (IP) reaction with trimesoyl chloride (TMC) and amine

Sang Gon Kim; Ki Tae Park; Byung-Hee Chun; Joona Bang; Sung Hyun Kim

2010-01-01

27

Saponification rates of esters in aqueous dioxane  

E-print Network

. sodium hydroxide, and 100 ml. of 1,4-dioxane. The mixture was; stirred and allowed to come to the temperature of the bath, at which time a sample was removed and titrated# This titration served to establish an initial concentration of the base... with rapid stirring.. By means of a volumetric pipet, fifty milliliter samples were withdrawn at timed intervals and discharged into an excess of standard hydrochloric acid, the excess being back-titrated with standard sodium hydroxide, phenolphthalein...

Christian, John Donald

2013-10-04

28

Which Powder is It?  

NSDL National Science Digital Library

In this chemistry challenge, learners identify an unknown white powder by comparing it with common household powders. Learners first explore what happens when baking soda, baking powder, and washing soda are mixed with water, vinegar, and PHTH (the indicator phenolphthalein mixed with alcohol and water). Learners then work to identify the unknown based on how it reacts with the known solutions. This is a simplified form of "qualitative analysis," which was historically an important approach chemists used for identifying unknown samples.

Sciencenter

2014-08-27

29

Analysis of plasma isoflavones by reversed-phase HPLC-multiple reaction ion monitoring-mass spectrometry  

Microsoft Academic Search

A HPLC-MS procedure for the rapid, sensitive and specific measurement of the isoflavones, daidzein, dihydrodaidzein, O-desmethylangolensin and genistein, in human plasma has been developed. Synthetic radiolabeled genistein conjugates were used for evaluation of optimum conditions for solid phase extraction. Biochanin A was added to plasma as a recovery marker for isoflavones and phenolphthalein glucuronide and 4-methylumbelliferone sulfate were added to

Lori Coward; Marion Kirk; Nicolas Albin; Stephen Barnes

1996-01-01

30

Visualization of turbulent reacting flow in a microscale nanoprecipitation reactor  

NASA Astrophysics Data System (ADS)

A flow visualization technique using the pH sensitive dye phenolphthalein was used to visualize and quantify turbulent reacting mixing in a microscale nanoprecipitation reactor. Phenolphthalein is colorless at pH lower than 8, but turns pink at higher pH, making it useful for visualizing acid-base reactions. Using this dye, turbulent reactive mixing in a confined impinging jets reactor (CIJR) was investigated. The reactor has two inlet streams, one at a pH of 3, and the other at a pH of 11. Phenolphthalein is also dissolved in both streams. A flash lamp with a extremely short pulse duration is used to freeze the turbulent motion of the fluids, and images are captured using a video camera. Quantitative mixing data are obtained by using a thresholding technique where local image intensities are transformed to binary signals which represent the local pH: 0 stands for pH lower than 8 and 1 for pH higher than 8. For each Reynolds number under consideration, thousands of realizations are acquired. Using this thresholding technique, probability density functions are obtained, allowing comparison to numerical simulations.

Shi, Yanxiang; Vishwanat, Somashekar; Olsen, Michael; Fox, Rodney

2009-11-01

31

An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc  

NASA Technical Reports Server (NTRS)

A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9 - 8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

Reid, M. A.

1978-01-01

32

An improved method for analysis of hydroxide and carbonate in alkaline electrolytes containing zinc  

NASA Technical Reports Server (NTRS)

A simplified method for titration of carbonate and hydroxide in alkaline battery electrolyte is presented involving a saturated KSCN solution as a complexing agent for zinc. Both hydroxide and carbonate can be determined in one titration, and the complexing reagent is readily prepared. Since the pH at the end point is shifted from 8.3 to 7.9-8.0, m-cresol purple or phenol red are used as indicators rather than phenolphthalein. Bromcresol green is recommended for determination of the second end point of a pH of 4.3 to 4.4.

Reid, M. A.

1978-01-01

33

The chemical and functional properties of commercial and modified lecithins  

E-print Network

) is the titratable acidity of the lecithin expressed as mg KOH/g of sample. 8oth the phospholipids and free fatty acids contribute the acidity to AV. An AV above 36 may indicate degradation of the lecithin or substandard soybeans. To determine AV, a known weight... of sample is dissolved in solvent and titrated with sodium hydroxide to the phenolphthalein endpoint (AOCS Official Method Ja 6-55). The water content of lecithin products is usually less than 1. 5/. Higher moisture levels in lecithin indicate a greater...

Zhang, Fan

2012-06-07

34

Tracking a Virus  

NSDL National Science Digital Library

Students simulate the spread of a virus such as HIV through a population by "sharing" (but not drinking) the water in a plastic cup with several classmates. Although invisible, the water in a few of the cups has already be tainted with the "virus" (sodium carbonate). After all the students have shared their liquids, the contents of the cups are tested for the virus with phenolphthalein, a chemical that causes a striking color change in the presence of sodium carbonate. Students then set about trying to determine which of their classmates were the ones originally infected with the virus.

Engineering K-Phd Program

35

Active oxygen doctors the evidence  

NASA Astrophysics Data System (ADS)

Investigation at the scene of a crime begins with the search for clues. In the case of bloodstains, the most frequently used reagents are luminol and reduced phenolphthalein (or phenolphthalin that is also known as the Kastle-Meyer colour test). The limitations of these reagents have been studied and are well known. Household cleaning products have evolved with the times, and new products with active oxygen are currently widely used, as they are considered to be highly efficient at removing all kinds of stains on a wide range of surfaces. In this study, we investigated the possible effects of these new cleaning products on latent bloodstains that may be left at a scene of a crime. To do so, various fabrics were stained with blood and then washed using cleaning agents containing active oxygen. The results of reduced phenolphthalein, luminol and human haemoglobin tests on the washed fabrics were negative. The conclusion is that these new products alter blood to such an extent that it can no longer be detected by currently accepted methods employed in criminal investigations. This inability to locate bloodstains means that highly important evidence (e.g. a DNA profile) may be lost. Consequently, it is important that investigators are aware of this problem so as to compensate for it.

Castelló, Ana; Francès, Francesc; Corella, Dolores; Verdú, Fernando

2009-02-01

36

Determination of Chlorinity of Water without the Use of Chromate Indicator  

PubMed Central

A new method for determining chlorinity of water was developed in order to improve the old method by alleviating the environmental problems associated with the toxic chromate. The method utilizes a mediator, a weak acid that can form an insoluble salt with the titrant. The mediator triggers a sudden change in pH at an equivalence point in a titration. Thus, the equivalence point can be determined either potentiometrically (using a pH meter) or simply with an acid-base indicator. Three nontoxic mediators (phosphate, EDTA, and sulfite) were tested, and optimal conditions for the sharpest pH changes were sought. A combination of phosphate (a mediator) and phenolphthalein (an indicator) was found to be the most successful. The choices of the initial pH and the concentration of the mediator are critical in this approach. The optimum concentration of the mediator is ca. 1~2?mM, and the optimum value of the initial pH is ca. 9 for phosphate/phenolphthalein system. The method was applied to a sample of sea water, and the results are compared with those from the conventional Mohr-Knudsen method. The new method yielded chlorinity of a sample of sea water of (17.58 ± 0.22)?g/kg, which is about 2.5% higher than the value (17.12 ± 0.22) g/kg from the old method. PMID:21461358

Hong, Tae-Kee; Kim, Myung-Hoon; Czae, Myung-Zoon

2010-01-01

37

Identification and Determination of Synthetic Pharmaceuticals as Adulterants in Eight Common Herbal Weight Loss Supplements  

PubMed Central

Background: Adulterated herbal weight loss products with containing undeclared synthetic drugs are common and responsible for many serious health damages. Objectives: The purpose of the study was to determine five synthetic adulterants in eight common herbal weight loss supplements, which are currently sold in Iran markets, to verify their presence in supplements, without mentioning on the labels. Materials and Methods: Eight common herbal weight loss samples were obtained from the Iran pharmaceutical market after advertising in the Persian language on satellite channels and internet. Five pharmacological classes of drugs used for weight loss, namely sibutramine, phenolphthalein, phenytoin, bumetanide and rimonabant, were investigated and quantified by GC-MS for the first three and LC-MS for the last two medications. Results: The most undeclared ingredients, which were illegally added include sibutramine, phenolphthalein, bumetanide, and phenytoin in the original super slim, herbaceous essence, super slim green lean, and fat loss, supplements, respectively. Rimonabant was not found. Caffeine, pseudoephedrine, theobromine and amfepramone were also found in the supplements using GC-MS assay. Conclusions: Adulterated synthetic substances were detected in the herbal weight loss products. Health care professionals should make people aware of the risks of taking herbal weight-loss supplements. PMID:24829782

Khazan, Marjan; Hedayati, Mehdi; Kobarfard, Farzad; Askari, Sahar; Azizi, Fereidoun

2014-01-01

38

Fabrication of three-dimensional helical microchannels with arbitrary length and uniform diameter inside fused silica.  

PubMed

We demonstrate an improved femtosecond laser irradiation followed by chemical etching process to create complex three-dimensional (3D) microchannels with arbitrary length and uniform diameter inside fused silica. A segmented chemical etching method of introducing extra access ports and a secondary power compensation is presented, which enables the fabrication of uniform 3D helical microchannels with length of 1.140 cm and aspect-ratio of 522. Based on this method, a micromixer which consists of a long helical microchannel and a y-tape microchannel was created inside the fused silica. We measured the mixing properties of the micromixer by injecting the phenolphthalein and NaOH solution through the two inlets of the y-tape microchannel. A rapid and efficient mixing was achieved in the 3D micromixer at a low Reynolds number. PMID:23041872

He, Shengguan; Chen, Feng; Liu, Keyin; Yang, Qing; Liu, Hewei; Bian, Hao; Meng, Xiangwei; Shan, Chao; Si, Jinhai; Zhao, Yulong; Hou, Xun

2012-09-15

39

Approaches to flame resistant polymeric materials  

NASA Technical Reports Server (NTRS)

Four research and development areas are considered for further exploration in the quest of more flame-resistant polymeric materials. It is suggested that improvements in phenolphthalein polycarbonate processability may be gained through linear free energy relationship correlations. Looped functionality in the backbone of a polymer leads to both improved thermal resistance and increased solubility. The guidelines used in the pyrolytic carbon production constitute a good starting point for the development of improved flame-resistant materials. Numerous organic reactions requiring high temperatures and the techniques of protected functionality and latent functionality constitute the third area for exploration. Finally, some well-known organic reactions are suggested for the formation of polymers that were not made before.

Liepins, R.

1975-01-01

40

Prediction of corrosion rates of water distribution pipelines according to aggressive corrosive water in Korea.  

PubMed

The drinking water network serving Korea has been used for almost 100 years. Therefore, pipelines have suffered various degrees of deterioration due to aggressive environments. The pipe breaks were caused by in-external corrosion, water hammer, surface loading, etc. In this paper, we focused on describing corrosion status in water distribution pipes in Korea and reviewing some methods to predict corrosion rates. Results indicate that corrosive water of lakes was more aggressive than river water and the winter was more aggressive compared to other seasons. The roughness growth rates of Dongbok lake showed 0.23 mm/year. The high variation of corrosion rates is controlled by the aging pipes and smaller diameter. Also the phenolphthalein test on a cementitious core of cement mortar lined ductile cast iron pipe indicated the pipes over 15 years old had lost 50-100% of their lime active cross sectional area. PMID:14982159

Chung, W S; Yu, M J; Lee, H D

2004-01-01

41

What Is the Opposite of Pandora's Box? Direct Analysis, Ambient Ionization, and a New Generation of Atmospheric Pressure Ion Sources  

PubMed Central

The introduction of DART and DESI sources approximately seven years ago led to the development of a new series of atmospheric pressure ion sources referred to as “ambient ionization” sources. These fall into two major categories: spray techniques like DESI or plasma techniques like DART. The selectivity of “direct ionization,” meaning analysis without chromatography and with little or no sample preparation, depends on the mass spectrometer selectivity. Although high resolution and tandem mass spectrometry are valuable tools, rapid and simple sample preparation methods can improve the utility of ambient ionization methods. The concept of ambient ionization has led to the realization that there are many more ways to form ions than might be expected. An interesting example is the use of a flint-and-steel spark source to generate ions from compounds such as phenolphthalein and Gramicidin S. PMID:24349926

B. Cody, Robert

2013-01-01

42

Growth of A1N by the chemical vapor reaction process and its application to lateral overgrowth on patterned sapphire substrates  

NASA Astrophysics Data System (ADS)

Growth of A1N on patterned sapphire substrates was studied. Deep grooves were made on sapphire substrates by a laser-induced backside wet etching technique. KrF excimer laser was irradiated at an interface between sapphire and phenolphthalein/ N-methyl-2-pyrrolidone solution, which acts as a super-heating liquid. An etch rate of sapphire was as high as 6 ?m/min for laser power of 1.0 J/cm 2. The A1N layer was grown on the patterned sapphire substrate by chemical vapor reaction process at 1190 °C for 1 h. On the inclined sidewall of the etched grooves, A1N grew with its c-axis perpendicular to the sidewall. This produced m-plane surfaces which were inclined around 20° to the basal plane of sapphire. A threading dislocation density of m-plane A1N domains was 8×10 8 cm -2.

Fujito, Kenji; Hashimoto, Tadao; Samonji, Katsuya; Speck, James S.; Nakamura, Shuji

2004-12-01

43

Purging and calorie absorption in bulimic patients and normal women.  

PubMed

Self-induced purging with laxatives is common among bulimic persons, who assume that purging reduces intestinal absorption of ingested calories. However, the efficacy of purging in reducing calorie absorption has never been studied, probably because the standard calorie balance procedure is expensive and time consuming. With a recently devised method, calorie absorption during a single day was measured to determine to what extent phenolphthalein or saline purge reduced calorie absorption. In two bulimic patients who regularly used laxatives for weight control and five normal young women, even extreme purging producing 4 to 6 L of diarrhea caused calorie absorption to decrease by only about 12% of calorie intake. The theoretical basis on which laxatives are taken for weight control is unsound. PMID:6190422

Bo-Linn, G W; Santa Ana, C A; Morawski, S G; Fordtran, J S

1983-07-01

44

Effects of pH indicators on various activities of chromatophroes of Rhodospirillum rubrum.  

PubMed

1. The effects of pH indicators on activities for ATP hydrolysis in the dark and ATP-Pi exchange in the dark were examined with chromatophores from Rhodospirillum rubrum. Of thirty-one pH indicators tested, eleven (metanil yellow, 2, 4-dinitrophenol, ethyl orange, bromocresol green, resazurin, neutral red, bromthymol blue, alpha-naphtholphthalein, o-cresolphthalein, phenolphthalein, and alizarin yellow G) almost completely inhibited the activities for ATP formation and ATP-Pi exchange at concentrations of 1 mM, and were studied in detail. 2. Of the eleven pH indicators, those other than alpha-naptholphthalein, o-cresolphthalein and phenolphthalein, when assayed at appropriate concentrations, inhibited ATP-Pi exchange, but not ATP hydrolysis. In ATP-Pi exchange, these eight pH indicators at the concentrations described above were competitive against Pi, and non-competitive against ATP. The remaining three kinds of pH indicators were non-competitive against either Pi or ATP, when assayed at concentrations of the dyes that inhibited both activities. 3. The amounts of pH indicators bound with chromatophores were measured. No correlation was found between the amounts of the bound dyes and the extents of their inhibition of either ATP formation or ATP-Pi exchange. 4. Ethyl orange (pKa=4.1) and 2, 4-dinitrophenol (pKa=3.9) stimulated ATP hydrolysis to the greatest extent. The latter dye was hardly bound with chromatophores. 5. The stimulatory effects of pH indicators on ATP hydrolysis were hardly affected by extraction of quinones from chromatophores. 6. Most of the pH indicators stimulated both succinate-cytochrome c2 and NADH-cytochrome c2 reductions in the dark. 7. The mechanism of uncoupling of the electron transfer system and the phosphorylation system by pH indicators and the mechanism of the coupling are discussed. PMID:5425

Hosoi, K; Soe, G; Kakuno, T; Horio, T

1975-12-01

45

Flammability and Photo-Stability of Selected Polymer Systems  

NASA Technical Reports Server (NTRS)

A systematic approach to the improvement of the flammability of epoxy resins, bisphenol-A polycarbonate poly(butylene terephthalate), and Nylon 6.6 by introducing halogens and loop functionality into the flame retardants is described. The phthalides (the loop functionality containing molecules) include 3,3-bis(4-bromophenyl)-phthalide, 3,3-bis(4-chlorophenyl)phthalide, and phenolphthalein. The phthalide containing epoxy resins are synthesized and characterized in comparison with the bisphenol-A epoxy resins in terms of flammability in the copolymer systems. The resins include diglycidyl ethers of phenolphthalein, bisphenol-A. tetrabromobisphenol-A, and tetraoromophenolphthalein. The vaporization of the phthalide additive in the polymers is observed in Thermal Gravimetric Analysis. The flame retardancy is primarily due to the presence of halogens. In the poly(butylene terephthalate) system, the cleavage of the C(sub aromatic) -B bond of the flame retardant additive enhances the crosslinking react ions between the aromatic rings resulting in an increase of char formation. In the epoxy resin systems, loop functionality contributes to char formation to a larger extent. The interaction between the epoxy resin and poly-(butylene terephthalate) follows the mechanism of insertion of the oxirane ring into the ester bond. This mechanism is studied by FT-IR. The investigation of the thermal properties of the char-forming phenol-formaldehyde resins is conducted to provide information for the systematic design of high temperature flame-resistant phenolics. NMR and FT-IR are used to characterize the oligomeric resins and the cured resins. The curing agents used in the study include formaldehyde, s-trioxane and terephthaloyl chloride. The brominated phenolic resins are found to have higher oxygen indices with lower char yields.

Lo, Jeelin

1981-01-01

46

High Performance Microreactor for Rapid Fluid Mixing and Redox Reaction of Ascorbic Acid  

E-print Network

A novel micro device with a mechanism of split and recombination (SNR) for rapid fluidic mixing and reaction, named a SNR micro-reactor, was designed, fabricated and systematically analyzed. This SNR micro-reactor possessing an in-plane dividing structure requires only simple fabrication. We investigated this reactor and compared it numerically and experimentally with a slanted-groove micromixer (SGM). From the numerical results the mixing indices and mixing patterns demonstrated that the mixing ability of the SNR micro-reactor was much superior to that of the SGM. From a mixing test with phenolphthalein and sodium hydroxide solutions, the mixing lengths of the SNR micro-reactor were less than 4 mm for a Reynolds number over a wide range (Re = 0.1 - 10). From a comparison of mixing lengths, the results revealed also that the SNR micro-reactor surpassed the SGM in mixing performance by more than 200 %. As a reaction length is a suitable test of the performance of a reactor, we introduced a redox reaction betwe...

Fang, Wei-Feng

2008-01-01

47

Quantitative estimation of carbonation and chloride penetration in reinforced concrete by laser-induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

The penetration profile of chlorine in a reinforced concrete (RC) specimen was determined by laser-induced breakdown spectroscopy (LIBS). The concrete core was prepared from RC beams with cracking damage induced by bending load and salt water spraying. LIBS was performed using a specimen that was obtained by splitting the concrete core, and the line scan of laser pulses gave the two-dimensional emission intensity profiles of 100 × 80 mm2 within one hour. The two-dimensional profile of the emission intensity suggests that the presence of the crack had less effect on the emission intensity when the measurement interval was larger than the crack width. The chlorine emission spectrum was measured without using the buffer gas, which is usually used for chlorine measurement, by collinear double-pulse LIBS. The apparent diffusion coefficient, which is one of the most important parameters for chloride penetration in concrete, was estimated using the depth profile of chlorine emission intensity and Fick's law. The carbonation depth was estimated on the basis of the relationship between carbon and calcium emission intensities. When the carbon emission intensity was statistically higher than the calcium emission intensity at the measurement point, we determined that the point was carbonated. The estimation results were consistent with the spraying test results using phenolphthalein solution. These results suggest that the quantitative estimation by LIBS of carbonation depth and chloride penetration can be performed simultaneously.

Eto, Shuzo; Matsuo, Toyofumi; Matsumura, Takuro; Fujii, Takashi; Tanaka, Masayoshi Y.

2014-11-01

48

Inhibitory effect of ciprofloxacin on ?-glucuronidase-mediated deconjugation of mycophenolic acid glucuronide.  

PubMed

The interaction between mycophenolate (MPA) and quinolone antibiotics such as ciprofloxacin is considered to reduce the enterohepatic recycling of MPA, which is biotransformed in the intestine from MPA glucuronide (MPAG) conjugate excreted via the biliary system; however, the molecular mechanism underlying this biotransformation of MPA is still unclear. In this study, an in vitro system was established to evaluate ?-glucuronidase-mediated deconjugation and to examine the influence of ciprofloxacin on the enzymatic deconjugation of MPAG and MPA resynthesis. Resynthesis of MPA via deconjugation of MPAG increased in a time-dependent manner from 5 to 60 min in the presence of ?-glucuronidase. Ciprofloxacin and phenolphthalein-?-d-glucuronide (PhePG), a typical ?-glucuronidase substrate, significantly decreased the production of MPA from MPAG in the ?-glucuronidase-mediated deconjugation system. In addition, enoxacin significantly inhibited the production of MPA from MPAG, while levofloxacin and ofloxacin had no inhibitory effect on MPA synthesis. Pharmacokinetic analysis revealed that ciprofloxacin showed a dose-dependent inhibitory effect on MPA production from MPAG via ?-glucuronidase with a half-maximal inhibitory concentration (IC50 ) value of 30.4 µm. While PhePG inhibited the ?-glucuronidase-mediated production of MPA from MPAG in a competitive manner, ciprofloxacin inhibited MPA synthesis via noncompetitive inhibition. These findings suggest that the reduction in the serum MPA concentration during the co-administration of ciprofloxacin is at least in part due to the decreased enterohepatic circulation of MPA because of noncompetitive inhibition of deconjugation of MPAG by intestinal ?-glucuronidase. PMID:24615849

Kodawara, Takaaki; Masuda, Satohiro; Yano, Yoshitaka; Matsubara, Kazuo; Nakamura, Toshiaki; Masada, Mikio

2014-07-01

49

Effects of subacute treatment with cocaine on activities of n-demethylase, UDP-glucuronyltransferase and sulfotransferase in WKY and SHR rat liver - sex and strain differences  

SciTech Connect

The effects of subacute treatment with cocaine on activities of cocaine N-demethylase, UDP-glucuronyltransferase (GT) toward 4-nitrophenol and phenolphthalein and sulfotransferase (ST) toward androsterone and 4-nitrophenol in livers from Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were investigated. Hepatic metabolism of cocaine was different between the sexes (with males having higher N-demethylase activity) and the strains (with WKY rats having higher activity). The effects of subacute cocaine administration on the activity of cocaine N-demethylase were also sex- and strain-related. Whereas cocaine administration increased activity of hepatic N-demethylase in both female strains, it decreased activity in male WKY and had no effect on activity in male SHR. Sex and strain-related as well as cocaine-induced differences were also found in activities of hepatic GT toward 4-nitrophenol and phenolphtalein as well as in activity of hepatic ST towards andersterone and 4-nitrophenol. These results suggest that some of the individual variation in the effects of cocaine may be due to sex and genetic differences in the hepatic metabolism of cocaine and/or in sexually and/or genetically-determined differences in how cocaine affects hepatic metabolism of other xenobiotics. 20 references, 4 figures.

Watanabe, H.K.; Hoskins, B.; Ho, I.K.

1988-01-01

50

Carbonation and pH in mortars manufactured with supplementary cementitious materials  

SciTech Connect

An investigation of carbonation in mortars and methods of measuring the degree of carbonation and pH change is presented. The mortars were manufactured using ordinary portland cement, pulverized fuel ash, ground granulated blast-furnace slag, metakaolin, and microsilica. The mortars were exposed to a carbon dioxide-rich environment (5% CO{sub 2}) to accelerate carbonation. The resulting carbonation was measured using phenolphthalein indicator and thermogravimetric analysis. The pH of the pore fluid and a powdered sample, extracted from the mortar, was measured to give an accurate indication of the actual pH of the concrete. The pH of the extracted powder mortar sample was found to be similar to the pH of the pore fluid expressed from the mortars. The thermogravimetric analysis suggested two distinct regions of transport of CO{sub 2} within mortar, a surface region where convection was prevalent and a deeper region where diffusion was dominant. The use of microsilica has been shown to decrease the rate of carbonation, while pulverized fuel ash and ground granulated blast-furnace slag have a detrimental effect on carbonation. Metakaolin has little effect on carbonation.

McPolin, D.O.; Basheer, P.A.M.; Long, A.E. [Queens University Belfast, Belfast (United Kingdom)

2009-05-15

51

Net primary productivity of some aquatic macrophytes in sewage-sullage mixture.  

PubMed

Sewage-sullage mixture from Raipur city is spread over a vast area surrounding the city. This mixture has a pH always above neutrality with high turbidity. Transparency was nil with the absence of phenolphthalein alkalinity and dissolved oxygen. Hardness was high with low nitrogen and phosphorus concentration. Human consumable. acquatic macrophytes are cultivated in such waste water. Net primary productivity of three macrophytes: Ipomoea aquatica, Marsilea quadrifolia and Nelumbo nucifera were evaluated while being cultivated in such sewage-sullage mixture. Productivity was determined either with periodic biomass removal (I. aquatica and M. quadrifolia) or through removing the biomass only once at the time of growing season (N. nucifera). Growing season productivity of up to 27.48. 19.81 and 9.49 g m(-2) and day(-1) and extrapolated productivity of up to 100.30, 72.31 and 34.64 mt. ha(-1) yr(-1) was recorded for I. aquatica. M. quadrifolia and N. nucifera respectively. Thus, these macrophytes are yielding a high amount of human consumable biomass from an area which neither be a useless wetland. PMID:12017265

Kanungo, V K; Sinha, S; Naik, M L

2001-07-01

52

An improved microfluidics approach for monitoring real-time interaction profiles of ultrafast molecular recognition  

NASA Astrophysics Data System (ADS)

Our study illustrates the development of a microfluidics (MF) platform combining fluorescence microscopy and femtosecond/picosecond-resolved spectroscopy to investigate ultrafast chemical processes in liquid-phase diffusion-controlled reactions. By controlling the flow rates of two reactants in a specially designed MF chip, sub-100 ns time resolution for the exploration of chemical intermediates of the reaction in the MF channel has been achieved. Our system clearly rules out the possibility of formation of any intermediate reaction product in a so-called fast ionic reaction between sodium hydroxide and phenolphthalein, and reveals a microsecond time scale associated with the formation of the reaction product. We have also used the developed system for the investigation of intermediate states in the molecular recognition of various macromolecular self-assemblies (micelles) and genomic DNA by small organic ligands (Hoechst 33258 and ethidium bromide). We propose our MF-based system to be an alternative to the existing millisecond-resolved "stopped-flow" technique for a broad range of time-resolved (sub-100 ns to minutes) experiments on complex chemical/biological systems.

Batabyal, Subrata; Rakshit, Surajit; Kar, Shantimoy; Pal, Samir Kumar

2012-04-01

53

[Analysis and identification of illegal constituents in health food products implicitly advertizing tonic or slimming effect in the National Institute of Health Sciences in Japan].  

PubMed

With the prefectural governments' aid of the purchase, the Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences (NIHS) successively has surveyed illegal constituents in health food products implicitly advertizing tonic or slimming effect since the fiscal year of 2002 (slimming type) or 2003 (tonic type). The average numbers of the analyzed products per year are about 100 (slimming type) and 150 (tonic type), respectively. We also continuously distribute standards of authentic samples of several illegal components such as N-nitrosofenfluramine (NFF) and sildenafil (SIL) to prefectural institutes and the average gross number per year is about 140. In the case of slimming type, the fact that the products containing NFF were widely sold in Japanese markets in 2002 is well known. In addition, phenolphthalein, fenfluramine, sibtramine, desdimethylsibtramine, orlistat, mazindol, Rhubarb, Senna Leaf, etc. have been found as illegal constituents. In the tonic type products, we have identified more than 20 synthetic compounds relating to the erectile dysfunction (ED) treatment drugs, SIL, vardenafil and tadalafil (TDF). Since 2005, their synthetic intermediates and the patented but non-approved PDE5 inhibitors also have been found. It should be noted that TDF was found in the shells of capsule in 2009 and that mutaprodenafil was found as pro-drug type illegal component in 2010. In this report identification method of these illegal constituents is briefly described and then analytical trend in this decade is reviewed. PMID:24492223

Goda, Yukihiro

2014-01-01

54

Electric charge-mediated coalescence of water droplets for biochemical microreactors  

PubMed Central

This work proposes the use of charged droplets driven by the Coulombic force as solution-phase reaction chambers for biological microreactions. A droplet can be charged near an electrode under dc voltage by direct contact to the electrode. This process is called electrical charging of droplet (ECOD). This charged droplet can then be transported rapidly between electrodes following the arc of an electric field line by exploiting electrostatic force. As on-demand electrocoalescence, both alkalization of phenolphthalein and bioluminescence reaction of luciferase in the presence of adenosine triphosphate are studied to test the feasibility of the biochemical microreactors using ECOD. Two oppositely charged droplets are merged to have a color change immediately after microchemical reaction. The applicability of an ECOD-driven droplet to measurement of glucose concentration is also tested. The glucose concentration is measured using a colorimetric enzyme-kinetic method based on Trinder’s reaction [J. Clin. Pathol. 22, 158 (1969)]. The color change in the merged droplet is detected with an absorbance measurement system consisting of a photodiode and a light emitting diode. PMID:20697585

Jung, Yong-Mi; Kang, In Seok

2010-01-01

55

A Full Automatic Device for Sampling Small Solution Volumes in Photometric Titration Procedure Based on Multicommuted Flow System  

PubMed Central

In this work, an automatic device to deliver titrant solution into a titration chamber with the ability to determine the dispensed volume of solution, with good precision independent of both elapsed time and flow rate, is proposed. A glass tube maintained at the vertical position was employed as a container for the titrant solution. Electronic devices were coupled to the glass tube in order to control its filling with titrant solution, as well as the stepwise solution delivering into the titration chamber. The detection of the titration end point was performed employing a photometer designed using a green LED (?=545 nm) and a phototransistor. The titration flow system comprised three-way solenoid valves, which were assembled to allow that the steps comprising the solution container loading and the titration run were carried out automatically. The device for the solution volume determination was designed employing an infrared LED (?=930 nm) and a photodiode. When solution volume delivered from proposed device was within the range of 5 to 105 ?l, a linear relationship (R = 0.999) between the delivered volumes and the generated potential difference was achieved. The usefulness of the proposed device was proved performing photometric titration of hydrochloric acid solution with a standardized sodium hydroxide solution and using phenolphthalein as an external indicator. The achieved results presented relative standard deviation of 1.5%. PMID:18317510

Borges, Sivanildo S.; Vieira, Glaucia P.; Reis, Boaventura F.

2007-01-01

56

Poly(?-caprolactone) Nanowebs Functionalized with ?- and ?-Cyclodextrins.  

PubMed

The effects of alpha- and gamma-cyclodextrins (?- and ?-CDs) on the thermal and crystal nucleation behavior of electrospun poly(?-caprolactone) (PCL) nanofibers have been investigated. PCL/CD composite nanofibers were obtained for the first time by electrospinning the mixture from chloroform/N,N-dimethylformamide (60:40). Scanning electron microscopy analyses indicated that neat PCL nanofibers have an average diameter of 400 nm, which increases with the addition of CDs. The presence of CDs on or in the electrospun PCL fibers in the electrospun mats was investigated using Fourier transform infrared spectroscopy, thermogravimetric analysis, and wide-angle X-ray diffraction analysis. Differential scanning calorimetry showed that the PCL/CD composite fibers exhibit higher crystallization temperatures and sharper crystallization exotherms with increased CD loading, indicating the ability of CDs to nucleate PCL crystallization. Water contact angle (WCA) measurements indicate an inverse relationship between WCA and ?- or ?-CD concentration up to 30% loading. Phenolphthalein absorption tests were performed to study the kinetics of their inclusion complex (IC) formation with CDs. Unexpectedly, ?-CD-functionalized nanowebs performed better than ?-CD. This might be because at elevated loadings some ?-CDs may have threaded over PCL chains and formed ICs, whereas ?-CD did not. With their encapsulation capabilities and their lowered hydrophobicity, PCL/CD composite fibers might have potential uses in medical applications, in particular as wound odor absorbants in dressings, because it is well known that CDs can form ICs with these odorants, thereby effectively removing them. PMID:25296366

Narayanan, Ganesh; Gupta, Bhupender S; Tonelli, Alan E

2014-11-10

57

Progress with Molecular Mixing Measurements & High Atwood Number Experiments at Texas A&M University  

NASA Astrophysics Data System (ADS)

Current progress with high Schmidt number molecular mixing measurements in a small Atwood number water channel facility is reported. In the experiments, the pH of the heavy (salt) and light (fresh) water streams is controlled by adding acid or alkali to each stream. As the two streams molecularly mix, the chemical reaction between the acid and alkali is marked by a phenolphthalein chemical indicator, which is imaged under backlit conditions. The current high Schmidt number (˜700) experiments have resulted in low measures of molecular mixing as compared with previous experiments and simulations at moderate Schmidt numbers. In addition, progress with measurements at high Atwood numbers (˜0.6) in a gas channel facility using helium and air is also reported. Instantaneous velocity and density measurements inside the mixing layer are obtained using a novel combined hot-wire / cold-wire anemometry technique, where temperature is used as a fluid marker. This technique provides detailed simultaneous velocity and density measurements which allows for determination of velocity and density variances, velocity-density cross-correlations, and their spectra.

Andrews, Malcolm J.; Kraft, Wayne N.; Mueschke, Nicholas J.

2007-11-01

58

Qualitative Analysis of Fourteen White Solids and Two Mixtures Using Household Chemicals  

NASA Astrophysics Data System (ADS)

This is a revised and expanded version of a previously published qualitative analysis scheme for the identification of 11 white solids using materials readily available in drugstores, supermarkets, or variety stores. Phenolphthalein has been eliminated because the FDA banned its use in over-the-counter laxatives; instead, tests for pH are conducted using red cabbage indicator. Once commonly used by diabetics to test urine, copper reduction tablets are no longer widely available and are replaced by a mixture of ingredients. Three white solids and two types of mixtures, commercial antacid tablets and baking powder, have been added to the scheme. All procedures can be done with the simplest of equipment. Amounts of solids are measured volumetrically and heat is supplied by contact with hot tap water. The use of household chemicals reduces waste disposal problems while making the experiment suitable for a laboratory exercise in a distance-learning course. This experiment can be adapted for many levels of instruction. In middle school only the safer tests should be included; honors general chemistry students can be asked to design an analysis scheme for the 14 household chemicals.

Oliver-Hoyo, Maria; Allen, Deedee; Solomon, Sally; Brook, Bryan; Ciraolo, Justine; Daly, Shawn; Jackson, Leia

2001-11-01

59

COMPACT and molecular structure in toxicity assessment: a prospective evaluation of 30 chemicals currently being tested for rodent carcinogenicity by the NCI/NTP.  

PubMed

A new series of 30 miscellaneous National Toxicology Program chemicals has been evaluated prospectively for carcinogenicity and overt toxicity by COMPACT (Computer Optimised Molecular Parametric Analysis for Chemical Toxicity. CYP1A and CYP2E1). Evaluations were also made by Hazardexpert, and for metal ion redox potentials; and these, together with COMPACT, were compared with results from the Ames test for mutagenicity in Salmonella, the micronucleus test, and 90-day subchronic rodent pathology. Seven of the 30 chemicals (nitromethane, chloroprene, xylenesulphonic acid, furfuryl alcohol, anthraquinone, emodin, cinnamaldehyde) were positive for potential carcinogenicity in the COMPACT evaluation; xylenesulphonic acid and furfuryl alcohol were only equivocally positive. Four of the 30 chemicals-scopolamine, D&C Yellow No. 11, citral, cinnamaldehyde-were positive by Hazardexpert; 6 of 30-D&C Yellow No. 11, 1-chloro-2-propanol, anthraquinone, emodin, sodium nitrite, cinnamaldehyde-were positive in the Ames test; 2 of 30-phenolphthalein and emodin-were positive in the in vivo cytogenetics test; and 3 of 30-molybdenum trioxide, gallium arsenide, vanadium pentoxide-were metal compounds with redox potentials of the metal/metal ion indicative of possible carcinogenicity. The overall prediction for carcinogenicity was positive for 12 of 30 chemicals: nitromethane, chloroprene, D&C Yellow No. 11, molybdenum trioxide, 1-chloro-2-propanol, furfuryl alcohol, gallium arsenide, anthraquinone, emodin, sodium nitrite, cinnamaldehyde, vanadium pentoxide). This overall prediction has been made on the basis of the results of the computer tests and from consideration of the information from bacterial mutagenicity, together with likely lipid solubility and pathways of metabolism and elimination. PMID:8933049

Lewis, D F; Ioannides, C; Parke, D V

1996-10-01

60

p53 induction as a genotoxic test for twenty-five chemicals undergoing in vivo carcinogenicity testing.  

PubMed Central

In vivo carcinogenicity testing is an expensive and time-consuming process, and as a result, only a relatively small fraction of new and existing chemicals has been tested in this manner. Therefore, the development and validation of alternative approaches is desirable. We previously developed a mammalian in vitro assay for genotoxicity based on the ability of cells to increase their level of the tumor-suppressor protein p53 in response to DNA damage. Cultured cells are treated with various amounts of the test substances, and at defined times following treatment, they are harvested and lysed. The lysates are analyzed for p53 by Western blot and/or enzyme-linked immunosorbent assay analysis. An increase in cellular p53 following treatment is interpreted as evidence for DNA damage. To determine the ability of this p53-induction assay to predict carcinogenicity in rodents and to compare such results with those obtained using alternate approaches, we subjected 25 chemicals from the predictive toxicology evaluation 2 list to analysis with this method. Five substances (citral, cobalt sulfate heptahydrate, D&C Yellow No. 11, oxymetholone, and t-butylhydroquinone) tested positive in this assay, and three substances (emodin, phenolphthalein, and sodium xylenesulfonate) tested as possibly positive. Comparisons between the results obtained with this assay and those obtained with the in vivo protocol, the Salmonella assay, and the Syrian hamster embryo (SHE) cell assay indicate that the p53-induction assay is an excellent predictor of the limited number of genotoxic carcinogens in this set, and that its accuracy is roughly equivalent to or better than the Salmonella and SHE assays for the complete set of chemicals. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:10504146

Duerksen-Hughes, P J; Yang, J; Ozcan, O

1999-01-01

61

COMPACT and molecular structure in toxicity assessment: a prospective evaluation of 30 chemicals currently being tested for rodent carcinogenicity by the NCI/NTP.  

PubMed Central

A new series of 30 miscellaneous National Toxicology Program chemicals has been evaluated prospectively for carcinogenicity and overt toxicity by COMPACT (Computer Optimised Molecular Parametric Analysis for Chemical Toxicity. CYP1A and CYP2E1). Evaluations were also made by Hazardexpert, and for metal ion redox potentials; and these, together with COMPACT, were compared with results from the Ames test for mutagenicity in Salmonella, the micronucleus test, and 90-day subchronic rodent pathology. Seven of the 30 chemicals (nitromethane, chloroprene, xylenesulphonic acid, furfuryl alcohol, anthraquinone, emodin, cinnamaldehyde) were positive for potential carcinogenicity in the COMPACT evaluation; xylenesulphonic acid and furfuryl alcohol were only equivocally positive. Four of the 30 chemicals-scopolamine, D&C Yellow No. 11, citral, cinnamaldehyde-were positive by Hazardexpert; 6 of 30-D&C Yellow No. 11, 1-chloro-2-propanol, anthraquinone, emodin, sodium nitrite, cinnamaldehyde-were positive in the Ames test; 2 of 30-phenolphthalein and emodin-were positive in the in vivo cytogenetics test; and 3 of 30-molybdenum trioxide, gallium arsenide, vanadium pentoxide-were metal compounds with redox potentials of the metal/metal ion indicative of possible carcinogenicity. The overall prediction for carcinogenicity was positive for 12 of 30 chemicals: nitromethane, chloroprene, D&C Yellow No. 11, molybdenum trioxide, 1-chloro-2-propanol, furfuryl alcohol, gallium arsenide, anthraquinone, emodin, sodium nitrite, cinnamaldehyde, vanadium pentoxide). This overall prediction has been made on the basis of the results of the computer tests and from consideration of the information from bacterial mutagenicity, together with likely lipid solubility and pathways of metabolism and elimination. PMID:8933049

Lewis, D F; Ioannides, C; Parke, D V

1996-01-01

62

Maternal hepatic and embryonic effects of 1,2,3,4-tetrachlorobenzene in the rat.  

PubMed

To assess possible maternal hepatic and reproductive effects of this uncharged, low molecular weight, lipophilic chlorinated benzene 0, 100, 300 and 1000 mg/kg/day of 1,2,3,4-tetrachlorobenzene (TCB) was orally administered to pregnant rats on days 9-13 of gestation and the animals were killed on day 14 of pregnancy. Phenobarbital and beta-naphthoflavone were administered to other pregnant rats as positive hepatic controls. Maternal mortality (7/19 rats) was increased and body weight gain was greatly decreased in the 1000 mg/kg/day TCB group. Liver to body weight ratio and hepatic microsomal protein content were unaffected by any TCB treatment. On day 14 maternal NADPH-cytochrome c reductase activity was increased at 1000 mg/kg/day, while the maternal hepatic microsomal cytochrome P-450 content was significantly induced by both 300 and 1000 mg/kg/day of TCB. Microsomal N-demethylation of aminopyrine was increased from 2.6 to 4.0 and 4.5 nmol/mg protein/min at doses of 300 and 1000 mg/kg TCB, respectively. However, maternal hepatic microsomal ethoxyresorufin O-deethylase activity was not consistently increased by TCB. Hepatic glutathione S-transferase activity towards 1,2-dichloro-4-nitrobenzene was increased only by the 1000 mg/kg/day TCB treatment. The rate of microsomal p-nitrophenol and phenolphthalein glucuronidation was increased by TCB administration. Embryonic growth was adversely affected by TCB treatment. Yolk sac diameter, embryonic crown-rump length, and head length were all decreased by treatment with 300 mg/kg/day TCB. This TCB treatment did not significantly elevate the number of dead or abnormal embryos. PMID:6857697

Kitchin, K T; Ebron, M T

1983-01-01

63

Study of dynamics and crystallization kinetics of 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile at ambient and elevated pressure  

NASA Astrophysics Data System (ADS)

The organic liquid ROY, i.e., 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, has been a subject of detailed study in the last few years. One interest in ROY lies in its polymorph-dependent fast crystal growth mode below and above the glass transition temperature. This growth mode is not diffusion controlled, and the possibility that it is enabled by secondary relaxation had been suggested. However, a previous study by dielectric relaxation spectroscopy had not been able to find any resolved secondary relaxation. The present paper reports new dielectric measurements of ROY in the liquid and glassy states at ambient pressure and elevated pressure, which were performed to provide more insight into the molecular dynamics as well as the crystallization tendency of ROY. In the search of secondary relaxation, a special glassy state of ROY was prepared by applying high pressure to the liquid state, from which secondary relaxation was possibly resolved. Thus, the role of secondary relaxation in crystallization of ROY remains to be clarified. Notwithstanding, the secondary relaxation present is not necessarily the sole enabler of crystallization. In an effort to search for possible cause of crystallization other than secondary relaxation, we also performed crystallization kinetics studies of ROY at different T and P combinations while keeping the structural relaxation time constant. The results show that crystallization of ROY speeds up with pressure, opposite to the trend found in the crystallization of ibuprofen studied up to 1 GPa. The dielectric relaxation and thermodynamic properties of ROY with phenolphthalein dimethylether (PDE) are similar in many respects, but PDE does not crystallize. Taking all the above into account, besides the secondary relaxation, the specific chemical structure, molecular interactions and packing of the molecules are additional factors that could affect the kinetics of crystallization found in ROY.

Adrjanowicz, K.; Kaminski, K.; Paluch, M.; Ngai, K. L.; Yu, Lian

2012-06-01

64

Nitric oxide as a modulator of intestinal water and electrolyte transport.  

PubMed

The role of nitric oxide in intestinal fluid and electrolyte secretion depends upon whether the conditions under study are physiological or pathophysiological. In physiological conditions, endogenous nitric oxide seems to be a proabsorptive molecule, based on the findings that nitric oxide synthase inhibitors reverse net fluid absorption to net secretion in mice, rats, guinea pigs, rabbits, and dogs. This proabsorptive mode involves the enteric nervous system, the suppression of prostaglandin formation, and the opening of basolateral K+ channels. However, in some pathophysiological states nitric oxide synthase may be produced at higher concentrations that are capable of evoking net secretion. Thus nitric oxide synthase contributes to the diarrheal response in trinitrobenzene sulfonic acid-induced ileitis in guinea pigs and is the mediator of the laxative action of several intestinal secretagogues including castor oil, phenolphthalein, bisacodyl, magnesium sulfate, bile salts, senna, and cascara in the rat. Corresponding with the in vivo results, nitric oxide-donating compounds or nitric oxide itself stimulate chloride secretion in the guinea pig and rat intestine in vitro. Exceptions are the diarrhea produced by bacterial enterotoxins in the rat, in which nitric oxide seems to have a proabsorptive role, and the mouse ileum in vitro, in which nitric oxide-donating compounds produce a net proabsorptive effect on basal ion transport. Several endogenous secretagogues (substance P, 5-hydroxytryptamine, interleukin-1beta), which are important mediators of the inflammatory bowel diseases, act, at least in part, through the liberation of nitric oxide. Clinical studies have shown that nitric oxide is elevated in several inflammatory bowel diseases and other secretory conditions including ulcerative colitis, Crohn's disease, toxic megacolon, diverticulitis, infectious gastroenteritis, and infantile methemoglobinemia. However, the determination of nitric oxide in secretory diarrhea per se does not give conclusive information on the nitric oxide contribution to clinical secretory diarrhea. PMID:9724140

Izzo, A A; Mascolo, N; Capasso, F

1998-08-01

65

p53 induction as a genotoxic test for twenty-five chemicals undergoing in vivo carcinogenicity testing.  

PubMed

In vivo carcinogenicity testing is an expensive and time-consuming process, and as a result, only a relatively small fraction of new and existing chemicals has been tested in this manner. Therefore, the development and validation of alternative approaches is desirable. We previously developed a mammalian in vitro assay for genotoxicity based on the ability of cells to increase their level of the tumor-suppressor protein p53 in response to DNA damage. Cultured cells are treated with various amounts of the test substances, and at defined times following treatment, they are harvested and lysed. The lysates are analyzed for p53 by Western blot and/or enzyme-linked immunosorbent assay analysis. An increase in cellular p53 following treatment is interpreted as evidence for DNA damage. To determine the ability of this p53-induction assay to predict carcinogenicity in rodents and to compare such results with those obtained using alternate approaches, we subjected 25 chemicals from the predictive toxicology evaluation 2 list to analysis with this method. Five substances (citral, cobalt sulfate heptahydrate, D&C Yellow No. 11, oxymetholone, and t-butylhydroquinone) tested positive in this assay, and three substances (emodin, phenolphthalein, and sodium xylenesulfonate) tested as possibly positive. Comparisons between the results obtained with this assay and those obtained with the in vivo protocol, the Salmonella assay, and the Syrian hamster embryo (SHE) cell assay indicate that the p53-induction assay is an excellent predictor of the limited number of genotoxic carcinogens in this set, and that its accuracy is roughly equivalent to or better than the Salmonella and SHE assays for the complete set of chemicals. PMID:10504146

Duerksen-Hughes, P J; Yang, J; Ozcan, O

1999-10-01

66

Investigation of the sorption properties of ?-cyclodextrin-based polyurethanes with phenolic dyes and naphthenates.  

PubMed

The sorption of p-nitrophenol (PNP), phenolphthalein (phth) and naphthenates (NAs) with ?-cyclodextrin (?-CD) based polyurethane sorbents from aqueous solutions are reported. The copolymer sorbents were synthesized at various ?-CD/diisocyanate monomer mole ratios (e.g., 1:1, 1:2, and 1:3) with diisocyanates of variable molecular size and hydrogen deficiency. The copolymer sorbents were characterized in the solid state using (13)C CP-MAS NMR spectroscopy, IR spectroscopy and elemental (C,H,N) analysis. The equilibrium sorption properties of the copolymer sorbents in aqueous solution were characterized using isotherm models at pH 4.6 and 9.0 for PNP, pH 9.0 for naphthenates and pH 10.5 for phth. UV-Vis spectroscopy was used to monitor the unbound fraction of the phenolic dyes in the aqueous phase, whereas, electrospray ionization mass spectrometry was used to monitor the unbound fraction of naphthenates. The sorption results of the copolymer sorbents were compared with a commercially available carbonaceous standard; granular activated carbon (GAC). The sorption properties and capacities of the copolymer sorbents (Q(m)) were estimated using the Sips isotherm. The sorption capacity for GAC was 2.15 mmol PNP/g, 0.0698 mmol phth/g, and 142 mg NAs/g, respectively, whereas the polymeric materials ranged from 0.471 to 1.60 mmol/g (PNP), 0.114 to 0.937 mmol/g (phth), and 0 to 75.5 mg/g (naphthenates), respectively, for the experimental conditions investigated. The observed differences in the sorption properties were attributed to the accessible surface areas and pore structure characteristics of the copolymer sorbents. The binding constant, K(eq), for copolymer materials for each sorbate is of similar magnitude to the binding affinity observed for native ?-CD. PNP showed significant binding onto the copolymer framework containing diisocyanate domains, whereas, negligible sorption to the sites was observed for phth and naphthenates. The ?-CD inclusion sites in the copolymer framework are concluded to be the main sorption site for phth and naphthenates through the formation of well-defined inclusion complexes. PMID:21255790

Mohamed, Mohamed H; Wilson, Lee D; Headley, John V; Peru, Kerry M

2011-04-01

67

Improved water and sodium absorption from oral rehydration solutions based on rice syrup in a rat model of osmotic diarrhea.  

PubMed

Rice syrup solids, rice protein, and casein hydrolysate were added to experimental oral rehydration solutions in various combinations and tested in a rat intestinal perfusion system. Chronic osmotic diarrhea was induced in juvenile rats by supplying the cathartic agents, magnesium citrate and phenolphthalein, in their drinking water for 1 week. The experimental oral rehydration solutions were compared with standard oral rehydration solutions containing 20 gm/L or 30 gm/L of glucose and with each other to determine if there were significant differences in net water, sodium, or potassium absorption. An oral rehydration solution containing 30 gm/L of rice syrup solids had a net water absorption rate significantly higher than that of the standard 20 gm/L glucose-based oral rehydration solution (2.1 +/- 0.62 versus 1.5 +/- 0.48 microliters/[min x cm], p less than 0.05). Casein hydrolysate did not significantly affect net water absorption. However, combinations of 30 gm/L rice syrup solids and 5 gm/L casein hydrolysate significantly increased (p less than 0.05) net sodium and potassium absorption compared with the 20 gm/L glucose-based oral rehydration solution but not versus rice syrup solids alone. Oral rehydration solutions containing 30 gm/L rice syrup solids plus 5 gm/L rice protein, and 30 gm/L rice syrup solids plus 5 gm/L casein hydrolysate, had net water absorption rates significantly higher than the rate of a 30 gm/L glucose-based oral rehydration solution (2.5 +/- 0.36 and 2.4 +/- 0.38, respectively, versus 0.87 +/- 0.40 microliters/[min x cm], p less than 0.05). Rice protein and casein hydrolysate, however, did not significantly affect net water, sodium, or potassium absorption when added to rice protein glucose-based oral rehydration solutions. An inverse correlation between osmolality and net water absorption was observed (r = -0.653, p less than 0.02). The data suggest that substitution of rice syrup solids for glucose in oral rehydration solutions will improve water absorption and that rice syrup solids in combination with protein hydrolysates may, in addition, promote better sodium and potassium uptake. PMID:2007957

Wapnir, R A; Litov, R E; Zdanowicz, M M; Lifshitz, F

1991-04-01

68

Self-Irradiation Effects on 99Mo Reagents and Products  

SciTech Connect

produced in 1996 and shipped to pharmaceutical houses for evaluation of compatibility with oxime solution used to precipitate `?vfo as the oxime complex is both air and light-sensitive, and containing a black precipitate that forms during shipment, presumably as a result of self- irradiation. Addition of sodium hypochlorite to the product solution prior to shipment prevents precipitate formation, indicating the precipitate is a reduced form of `%lo. to remove any precipitate. Duplicate aliquots of the filtered samples were titrated to a phenolphthalein irradiation and afler standing at room temperature for 86.4 hours. Precipitates were washed to a FTIR analysis of the white precipitate showed it to be alpha benzoin oxime. Since the basic After 86.4 hours, no precipitate had formed in bottles containing sodium hypochlorite. Black precipitate had formed in all bottles that did not contain sodium hypochlorite after 14.4 hours. The precipitate appeared to initially form on the surface of the HDPE sample bottles and Black precipitate was first noticed in sample set 1 after 28.8 hrs' irradiation. No visible sample containing precipitate was kept at room temperature in the original bottle. Precipitate in sample sets 2 and 3. Since no precipitate formed in these bottles, this was equivalent to duplicate samples. Once the precipitate in the 20-mL aliquots that had been set aside had returned to sample sets 1 through 3 and the samples with redissolved precipitate all experienced an average decrease in base strength of 0.013 meq mL-l. Sample 1-C had a decrease of 0.004 meq mL-l and sample 1-D had returned to the initial value of 0.198 meq mL-l. Raman spectra for the black precipitate from samples l-C, 1-D and supplemental sample set 1 Fig. 2. Raman spectra of the black precipitate formed in 9%40 product solutions after 28.8,43.2, 72 and 86.4 hours of `oCo irradiation in Sandia's Gamma Irradiation Facility. increase with time, as seen in the titration of 1-C and 1-D samples. The precipitate does not expect to see precipitate in the glass bottles. The fact that no precipitate is observed when the no precipitate is observed in a glass container is an indication that the rates of molybdenum that precipitate does not form when the solution is in a glass bottle. A hydrogen source other

Carson, S.D.; Garcia, M.J.; McDonald, M.J.; Simpson, R.L.; Tallant, D.R.

1998-10-07