Sample records for phenolphthalein

  1. Molecular Structure of Phenolphthalein

    NSDL National Science Digital Library


    Phenolphthalein was first made in 1880. The compound is a good pH indicator because it turns red in a solution with a pH above 8. Phenolphthalein can also be used as a laxative. When used for therapeutic purposes it can cause hypersensitivity. Phenolphthalein also colors urine and other bodily excretions a pink or red color when it is present in the body.

  2. Plasticized phenolphthalein polycarbonate

    NASA Technical Reports Server (NTRS)

    Harrison, E. S.


    Phenolphthalein polycarbonate was successfully plasticized with polychlorinated biphenyls (e.g., Aroclor 1231) or tricresyl phosphate and cast from tetrahydrofuran to give clear films without loss of fire resistance. At loadings of 20 to 30 percent plasticizer the Tg was lowered to approximately 100 C which would render phenolphthalein polycarbonate easily moldable. Although these materials had some mechanical integrity as shown by their film forming ability, the room temperature toughness of the plasticized polymer was not significantly improved over unmodified polymer.

  3. Synthesis and characterization of cardo polysulfonates of phenolphthalein

    Microsoft Academic Search

    D. R Godhani; M. R Sanariya; Y. V Patel; P. H Parsania


    Cardo polysulfonates have been synthesized by condensing phenolphthalein (0.01 mol) with 4,4?-diphenyl disulfonyl chloride\\/4,4?-diphenyl ether disulfonyl chloride\\/4,4?-diphenyl methane disulfonyl chloride\\/3,3?-benzophenone disulfonyl chloride (0.01 mol) by using water–1,2-dichloroethane (2:1 v\\/v) as an acid acceptor and 0.2% CTAB as an interphase, alkali (0.02 mol) as an emulsifier. The reaction time and temperature were 3 h and 0 °C, respectively. IR and NMR

  4. Phenolphthalein and bisacodyl: assessment of genotoxic and carcinogenic responses in heterozygous p53 (+/-) mice and syrian hamster embryo (SHE) assay.


    Stoll, R E; Blanchard, K T; Stoltz, J H; Majeska, J B; Furst, S; Lilly, P D; Mennear, J H


    Phenolphthalein (800 and 2400 mg/kg/day by gavage and 2400 mg/kg/day by diet) and bisacodyl (800-500, 4000-2000, and 8000 mg/kg/day by gavage) were administered to 15 male and 15 female and 20 male and 20 female p53(+/-) mice respectively for 26 weeks to investigate the potential carcinogenicity of each compound. Toxicokinetic analyses confirmed systemic exposure. p-Cresidine was administered by gavage (400 mg/kg/day) and served as the positive control agent in each study. Dietary phenolphthalein reduced survival in both sexes and early deaths were attributed to thymic lymphoma. No bisacodyl-related neoplasms were observed. Regardless of route of administration to p53(+/-) mice, phenolphthalein but not bisacodyl was unequivocally genotoxic, causing increased micronuclei in polychromatic erythrocytes. In the Syrian hamster embryo (SHE) cell transformation assay, phenolphthalein caused increases in morphologically transformed colonies, thereby corroborating NTP's earlier reports, showing phenolophthalein has potential carcinogenic activity. Bisacodyl was negative in the SHE assay. Results of these experiments confirm an earlier demonstration that dietary phenolphthalein causes thymic lymphoma in p53(+/-) mice and show that (1) phenolphthalein causes qualitatively identical results in this transgenic model regardless of route of oral administration, (2) phenolphthalein shows evidence of micronucleus induction in p53(+/-) mice for up to 26 weeks, (3) phenolphthalein induced transformations in the in vitro SHE assay, and (4) bisacodyl in p53(+/-) mice induces neither drug-related neoplasm, nor micronuclei in polychromatic erythrocytes, and did not induce transformations in the in vitro SHE assay. PMID:16373391

  5. Interaction of ?-Cyclodextrin with Unsaturated and Saturated Straight Chain Fatty Acid Anions Studied by Phenolphthalein Displacement

    Microsoft Academic Search

    Stavroula G. Skoulika; Constantinos A. Georgiou; Moschos G. Polissiou


    The interaction of ß-cyclodextrin (ß-CD) with palmitoleate, linolenate, caprinate and caprylate was studied by the displacement of phenolphthalein (PHP) from the ß-CD cavity. Absorbance values of ß-CD–PHP solutions at 550 nm in 0.020 mol L-1 Na2CO3 buffer, pH 10.5, at 21.0 ± 0.5 °C, increased as the fatty acid anion was added. The concentration range of fatty acid anion used

  6. Ultraviolet irradiation induced changes in the surface of phenolphthalein poly(ether sulfone) film

    Microsoft Academic Search

    Xianqiang Pei; Qihua Wang


    Changes in surface characteristics of phenolphthalein poly(ether sulfone) (PES-C) film induced by ultraviolet (UV) irradiation were investigated. The surface properties of the pristine and irradiated films were studied by attenuated total-reflection FTIR (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), contact angle measurements and atomic force microscopy (AFM). It was found that photooxidation degradation took place on the sample surface after irradiation and

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

    PubMed Central

    Ailincai, Daniela


    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

  8. Detection and quantitation of trace phenolphthalein (in pharmaceutical preparations and in forensic exhibits) by liquid chromatography-tandem mass spectrometry, a sensitive and accurate method.


    Sharma, Kakali; Sharma, Shiba P; Lahiri, Sujit C


    Phenolphthalein, an acid-base indicator and laxative, is important as a constituent of widely used weight-reducing multicomponent food formulations. Phenolphthalein is an useful reagent in forensic science for the identification of blood stains of suspected victims and for apprehending erring officials accepting bribes in graft or trap cases. The pink-colored alkaline hand washes originating from the phenolphthalein-smeared notes can easily be determined spectrophotometrically. But in many cases, colored solution turns colorless with time, which renders the genuineness of bribe cases doubtful to the judiciary. No method is known till now for the detection and identification of phenolphthalein in colorless forensic exhibits with positive proof. Liquid chromatography-tandem mass spectrometry had been found to be most sensitive, accurate method capable of detection and quantitation of trace phenolphthalein in commercial formulations and colorless forensic exhibits with positive proof. The detection limit of phenolphthalein was found to be 1.66 pg/L or ng/mL, and the calibration curve shows good linearity (r(2) = 0.9974). PMID:23106487

  9. Phenolphthalein and Bisacodyl: Assessment of Genotoxic and Carcinogenic Responses in Heterozygous p53 (+\\/-) Mice and Syrian Hamster Embryo (SHE) Assay

    Microsoft Academic Search

    R. E. Stoll; K. T. Blanchard; J. H. Stoltz; J. B. Majeska; S. Furst; P. D. Lilly; J. H. Mennear


    Phenolphthalein (800 and 2400 mg\\/kg\\/day by gavage and 2400 mg\\/kg\\/day by diet) and bisacodyl (800-500, 4000-2000, and 8000 mg\\/kg\\/day by gavage) were administered to 15 male and 15 female and 20 male and 20 female p53+\\/? mice respectively for 26 weeks to investigate the potential carcinogenicity of each compound. Toxicokinetic analyses confirmed systemic exposure. p-Cresidine was administered by gavage (400

  10. Phenolphthalein-based Poly(arylene ether sulfone nitrile)s Multiblock Copolymers As Anion Exchange Membranes for Alkaline Fuel Cells.


    Lai, Ao Nan; Wang, Li Sha; Lin, Chen Xiao; Zhuo, Yi Zhi; Zhang, Qiu Gen; Zhu, Ai Mei; Liu, Qing Lin


    A series of phenolphthalein-based poly(arylene ether sulfone nitrile)s (PESN) multiblock copolymers containing 1-methylimidazole groups (ImPESN) were synthesized to prepare anion exchange membranes (AEMs) for alkaline fuel cells. The ion groups were introduced selectively and densely on the unit of phenolphthalein as the hydrophilic segments, allowing for the formation of ion clusters. Strong polar nitrile groups were introduced into the hydrophobic segments with the intention of improving the dimensional stability of the AEMs. A well-controlled multiblock structure was responsible for the well-defined hydrophobic/hydrophilic phase separation and interconnected ion-transport channels, as confirmed by atomic force microscopy and small angle X-ray scattering. The ImPESN membranes with low swelling showed a relatively high water uptake, high hydroxide ion conductivity together with good mechanical, thermal and alkaline stability. The ionic conductivity of the membranes was in the range of 3.85-14.67×10(-2) S·cm(-1) from 30 to 80 °C. Moreover, a single H2/O2 fuel cell with the ImPESN membrane showed an open circuit voltage of 0.92 V and a maximum power density of 66.4 mW cm(-2) at 60 °C. PMID:25825954

  11. Kinetics of the Fading of Phenolphthalein in Alkaline Solution.

    ERIC Educational Resources Information Center

    Nicholson, Lois


    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)

  12. Simultaneous multiwavelength study of the reaction of phenolphthalein with sodium hydroxide

    PubMed Central

    Tam, K. Y.


    A photodiode array (PDA) spectrophotometer was used to study the fading reaction of phenolpthalein in dilute sodium hydroxide solution. The principal component analysis (PCA) method was employed to identify the number of light absorbing species in the kinetics system. The target factor analysis (TFA) procedure, coupled with the Broyden-Fletcher-Goldfard-Shanno (BFGS) optimization method, was applied to the observed data to deduce the rate constants and the concentration-time profile of the reaction. The internal referencing method was shown to be essential in improving the quality of data obtained by a single beam PDA spectrophotomer. PMID:18924946

  13. Transparent polymeric laminates

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.


    Laminate prepared from epoxy-boroxine and phenolphthalein polycarbonate has high mechanical strength at elevated temperature and is resistant to impact, fire, and high-energy thermal radiation. Polycarbonate is prepared by reaction of phenolphthalein with phosgene in presence of amine catalyst and immiscible organic solvent phase.

  14. Complex patterns in reactive microemulsions: Self-organized nanostructures?

    E-print Network

    Epstein, Irving R.

    and Engineering News, a correspondent wrote, "We have re- cently prepared a nanomaterial in our laboratory this nanomaterial `phenolphthalein' subject to a patent search to see if the name is not already in use."5 Phe

  15. The Best Enzyme Investigation Ever? Probably.

    ERIC Educational Resources Information Center

    Cooper, Phil


    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)

  16. The Plague Generation.

    ERIC Educational Resources Information Center

    Jones, Richard C.


    Describes an activity to simulate the geometries of a spreading pathogen such as HIV throughout a generation. Students exchange "bodily fluids" three times and are then tested for the presence of "infection." Materials used include base solutions (NaOH or KOH), phenolphthalein (pH indicator), clear plastic cups, and an eye dropper. (PR)

  17. Ultrasonic Mixing in Microfluidic Channels Using Integrated Transducers

    E-print Network

    Khuri-Yakub, Butrus T. "Pierre"

    Ultrasonic Mixing in Microfluidic Channels Using Integrated Transducers Goksen G. Yaralioglu,* Ira, Stanford, California 94305 This paper presents a microfluidic mixer that uses acous- tic stirring created by mixing phenolphthalein solution and sodium hydroxide dissolved in ethyl alcohol. Flow rates on the order

  18. Factors Affecting the Quality of Texas Butter as Revealed by a Statewide Survey. 

    E-print Network

    Shepardson, C. N. (Charles Noah); Arbuckle, W. S. (Wendell Sherwood); Hanson, F. E. (Frank Edwin)


    .O.A.C. (2) with the exception that Nile blue indicator, 0.2 per cell: of Nile blue in alcohol solution, was used instead of phenolphthalein. Th. Nile blue indicator gave a much sharper titration end point. This Wac especially true when the alcoholic...

  19. Field Test for Titratable Acidity in Milk

    Microsoft Academic Search

    H. O. Jaynes; M. G. Pearsall; H. C. Holt


    A field test was developed to enable milk haulers to assess titratable acidity at pickup. The test involved adding a volume of milk to a set volume of standard base in calibrated screwcapped test tubes. Judgment was based on final color after adding phenolphthalein. No color change indicated titratable acidity above a chosen cutoff point, and the typical pink color


    Microsoft Academic Search

    Carl S. Kirby; Charles A. Cravotta


    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

  1. Determination of Binding Constants by Flow Injection Gradient Technique

    E-print Network

    Reid, Scott A.

    of inclusion complex formation between -cyclodextrin ( -CD) and phenolphthalein and of the incorporation for the determination of binding constants of substrates with cyclodextrins or micelles. The concentration gradient Complex formations through noncovalent interactions are known to play an essential role in processes

  2. Visualization of turbulent reactive mixing in a planar microscale confined impinging-jet reactor

    Microsoft Academic Search

    Yanxiang Shi; Vishwanath Somashekar; Rodney O. Fox; Michael G. Olsen


    Turbulent reactive mixing in a rectangular microscale confined impinging-jet reactor was investigated using the pH indicator phenolphthalein in this study for three different jet Reynolds numbers Rej = 25, 1000 and 1500. Laminar flow was observed at Rej = 25 whereas the flow was turbulent at Rej = 1000 and 1500. An image processing technique was applied to instantaneous images

  3. A method of ranking the aggressive nature of chloride contaminated concrete

    Microsoft Academic Search

    G. Sergi; G. K. Glass


    In this work, previously reported titration data obtained on cement pastes and concretes are analysed. It is postulated that the inhibitive nature of concretes may be quantified by titrating a ground suspension to the endpoint indicated by phenolphthalein while the aggressive chloride content may be determined from the soluble chloride at the endpoint of this titration. Thus, the aggressive nature

  4. Molecular Models of Indicators

    NSDL National Science Digital Library

    The article by Nicholas C. Thomas and Stephen Faulk on "Colorful Chemical Fountains" (1) reminds us that color—the colors of acid–base indicators or of metal complexes—is responsible for many of us developing an interest in chemistry. The featured molecules this month are the acid and base forms of three common indicators–phenolphthalein, methyl orange, and methyl red. These three substances display interesting structural features as the pH-induced transformation from one form to another takes place in three different ways. In the case of phenolphthalein, the lactam ring is cleaved on deprotonation to produce a carboxyl group with the concomitant removal of a proton from a phenolic group. In methyl orange, one of the nitrogen atoms is protonated in the acid form, and that proton is lost in the base form. In methyl red, a carboxylic acid function is deprotonated. There are many other interesting aspects of acid–base indicators. Since most plants and fruits contain pigments that show a color change in some pH range, it is difficult to state with any degree of certainty when these changes were first put to use in a systematic fashion. The Spanish alchemist Arnaldus de Villa Nova (Arnold of Villanova) is purported to have used litmus in the early 14th century. In general systematic use of indicators is traced to the latter half of the nineteenth century with the development of the three synthetic indicators described above. Many students will be familiar with the use of phenolphthalein to identify blood—often shown on the various forensic chemistry TV dramas by dropping some solution on a cotton swab that has been used to pick up some of the sample in question. If the swab turns red we frequently hear "It's blood". The reality of using phenolphthalein in this way is more complicated. The test is presumptive for the presence of blood, but not conclusive. It is not an acid–base reaction but rather, in the presence of hydrogen peroxide, relies on hemoglobin to catalyze the oxidation of phenolphthalein. An interesting assignment for students in a high-school or non-majors course would be to have them explore the details of this Kastle–Meyers test to see just what is involved in the correct application of the test, and what factors complicate the process. For example, would tomato juice infused with asparagus juice give a positive Kastle–Meyers test? Historically phenolphthalein was used in a variety of laxatives. Recently that usage has been discontinued due to concern about the carcinogenic nature of the substance. A review of the history of the controversy surrounding the use of phenolphthalein in laxatives would make a good research paper at the high-school level. Lastly, students with some practice building structures and performing calculations might wish to explore the structures of two other forms of phenolphthalein—one found in very acidic solutions, having an orange color, and one found in very basic solutions that is colorless.

  5. Thermoplastic polymers for improved fire safety

    NASA Technical Reports Server (NTRS)

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


    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.

  6. Effect of thermoplastic coating on interfacial adhesion of oxygen-plasma-pretreated PBO/PPESK composites

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangyi; Chen, Ping; Han, Debin; Yu, Qi; Ding, Zhenfeng; Zhu, Xiuling


    To improve the interfacial adhesion of PBO/PPESK composite, thermoplastic resins were coated onto the fiber surface after plasma pretreatment. Two coating resins applied in this study were chemically linked with the plasma pretreated fibers, which was confirmed by X-ray photoelectron spectroscopy. The fiber surface morphologies and wettability were analyzed by scanning electron microscope (SEM) and dynamic contact angle analysis, respectively. The interfacial adhesion performance of the PBO fiber-reinforced PPESK composite was measured by interlaminar shear strength (ILSS) and water absorption tests. Fracture mechanisms of the composites were examined by SEM. The results indicated that after coating the surface wettability was improved and the ILSS had an increment of 80.8% for phenolphthalein poly (ether ketone) coating and 30.3% for phenolphthalein poly (ether sulfone) coating.

  7. Rapid discrimination of slimming capsules based on illegal additives by electronic nose and flash gas chromatography.


    Xia, Zhenzhen; Cai, Wensheng; Shao, Xueguang


    The discrimination of counterfeit and/or illegally manufactured medicines is an important task in the pharmaceutical industry for pharmaceutical safety. In this study, 22 slimming capsule samples with illegally added sibutramine and phenolphthalein were analyzed by electronic nose and flash gas chromatography. To reveal the difference among the different classes of samples, principal component analysis and linear discriminant analysis were employed to analyze the data acquired from electronic nose and flash gas chromatography, respectively. The samples without illegal additives can be discriminated from the ones with illegal additives by using electronic nose or flash gas chromatography data individually. To improve the performance of classification, a data fusion strategy was applied to integrate the data from electronic nose and flash gas chromatography data into a single model. The results show that the samples with phenolphthalein, sibutramine and both can be classified well by using fused data. PMID:25447122

  8. Forced Rayleigh scattering from non-harmonic gratings applied to complex diffusion processes in glass-forming liquids

    NASA Astrophysics Data System (ADS)

    Veniaminov, Andrey V.; Sillescu, Hans


    Tracer diffusion of 9,10-phenanthrenequinone (PQ) and its photoproduct in super-cooled phenolphthalein-dimethyl-ether (PDE) was studied by forced Rayleigh scattering. In order to investigate the spatial frequency dependence of the grating dynamics, several spatial harmonics of the grating with non-sinusoidal phase profile produced by non-linear recording were monitored. An optical scheme with a diverging reading beam is proposed for simultaneous reconstruction of the harmonic components.



    Cullen, G E; Taylor, H D


    1. The use of the ears of rabbits is proposed in testing the irritant effect of antiseptics. 2. It is necessary, because of individual variations, to use solutions having definite irritant actions as controls. 3. 0.5 per cent sodium hypochlorite solutions have minimum irritant effects over a range of alkalinity of from about 100 to 1,000 times that of water (pH about 9 to 10). Solutions may be adjusted within these limits by use of the end-points of powdered phenolphthalein, of alcoholic solutions of either o-cresolphthalein or phenolphthalein. 4. Sodium hypochlorite solutions kept within the above range of alkalinity by either borate or carbonate buffer salts, i.e. Dakin's solution, show the same irritative properties whether made from bleaching powder and sodium carbonate, or from chlorine and sodium carbonate. 5. Electrolytically prepared solutions of the same concentration have similar irritant action. 6. Solutions, however, that have an alkalinity less than that indicated by the end-point of alcoholic phenolphthalein solutions (pH of 8.5 to 8.8) or greater than that indicated by the end-point to powdered phenolphthalein (pH of 10.2) are intensely irritating. 7. 0.5 per cent sodium hypochlorite solution from which most of the calcium has been precipitated and calcium hypochlorite solution of equivalent hypochlorite concentration are only slightly irritating. 8. 2 per cent chloramine-T solution has no irritant action. 9. 5 per cent dichloramine-T in chlorcosane and chlorcosane alone irritate rabbit ears to a slight degree only. PMID:19868288

  10. 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.

  11. Structure in turbulent mixing layers and wakes using a chemical reaction

    Microsoft Academic Search

    R. Breidenthal


    Plane turbulent mixing between two streams of water which contained dilute chemical reactants was studied in a new blow-down water tunnel. In a diffusion-limited reaction, a pH indicator, phenolphthalein, in one stream mixed and reacted with a base, sodium hydroxide, in the other stream to form a visible reaction product. The product was found to exist, as expected, in concentrated

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

    Microsoft Academic Search

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


    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


    Microsoft Academic Search

    Zhonggang Wang; Tianlu Chen; Jiping Xu


    A series of cardo polyaryletherketones and polyaryletersulfones containing alkyl substituents of a different kind, number and volume were synthesized from bis(4-nitrophenyl)ketone or bis(4-fluorophenyl)sulfone with various alkyl substituted phenol-phthaleins by polycondensation using K2CO3 as catalyst. Their chemical and aggregation structures were confirmed by FT-IR, H-NMR and WAXD. The resulting polymers were soluble in a variety of common polar solvents and, transparent,

  14. Fish populations of Fairfield Reservoir, Texas, ten years after impoundment and the effects of the introduction of Tilapia aurea 

    E-print Network

    Hanifen, James Gregory


    with the fact that power plant operations were in- itiated during his investigation. Dissolved oxygen concentrations, pH, and turbidity values were comparable with his data. He reports, how- ever, finding phenolphthalein alkalinity and total alkalinity higher... and seines with results of previous investigations are given in Tables 2 and 3, respectively. Speegle (1972) reported a game:non-game fish species ratio from gillnet catch data throughout the year of I:0. 7. Seidensticker (1977) reported a slight decline...

  15. Morphological and Spatial Effects on Toughness and Impact Damage Resistance of PAEK-toughened BMI and Graphite Fiber Composite Laminates

    Microsoft Academic Search

    Cheng Qunfeng; Fang Zhengping; Xu Yahong; Yi Xiao-su


    The microstructure property relationships have been studied in terms of glass transition behavior, phase morphology, and fracture toughness on thermoplastic polyetherketone with a phenolphthalein side group (PAEK) toughened bismaleimdes (BMI) resins, and in terms of interlaminar morphology and compression after impact (CAI) on the graphite fiber (T700SC), the reinforced BMI matrix composites that are toughened with a so-called ex-situ concept,

  16. Nanocontainer-based corrosion sensing coating.


    Maia, F; Tedim, J; Bastos, A C; Ferreira, M G S; Zheludkevich, M L


    The present paper reports on the development of new sensing active coating on the basis of nanocontainers containing pH-indicating agent. The coating is able to detect active corrosion processes on different metallic substrates. The corrosion detection functionality based on the local colour change in active cathodic zones results from the interaction of hydroxide ions with phenolphthalein encapsulated in mesoporous nanocontainers which function as sensing nanoreactors. The mesoporous silica nanocontainers are synthesized and loaded with pH indicator phenolphthalein in a one-stage process. The resulting system is mesoporous, which together with bulkiness of the indicator molecules limits their leaching. At the same time, penetration of water molecules and ions inside the container is still possible, allowing encapsulated phenolphthalein to be sensitive to the pH in the surrounding environment and outperforming systems when an indicator is directly dispersed in the coating layer.The performed tests demonstrate the pH sensitivity of the developed nanocontainers being dispersed in aqueous solutions. The corrosion sensing functionality of the protective coatings with nanocontainers are proven for aluminium- and magnesium-based metallic substrates. As a result, the developed nanocontainers show high potential to be used in a new generation of active protective coatings with corrosion-sensing coatings. PMID:24045136

  17. Visualization of turbulent reacting flow in a microscale nanoprecipitation reactor

    NASA Astrophysics Data System (ADS)

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


    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.

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

    NASA Technical Reports Server (NTRS)

    Reid, M. A.


    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.

  19. A Chemical Study of the Grape Fruit

    E-print Network

    Seibel, C. W.


    , depending on surrounding conditions. The juice itself has a slightly acid taste citric acid present. The amount of citric acid present in the juice may be found by titrating 6.8 c . c of it with N/lO NaOH. Phenolphthalein makes a very good...) Average Weight, grams 357.00 Rind, per cent 23.50 Seeds, per cent 3.70 Juice, per cent 33.30 Solids in juice 13.20 Total sugars 9.50 Cane sugar 5.00 Acid in juice as citric 2.70 ...

  20. Development and the Educational Effect of a System of the Corrosion of Iron and the Anti-corrosion Ability of Conductive Polymer Polyaniline

    NASA Astrophysics Data System (ADS)

    Yano, Jun; Nakamura, Noriyuki; Yamazaki, Suzuko; Ichimori, Hayato; Osaki, Nobukazu; Okano, Hiroshi

    Few general chemistry textbooks of high schools, colleges and universities introduce the corrosion of iron into the oxidation-reduction (redox) section, although the corrosion is very popular phenomena for students. Besides, no description appears about conductive polymers as anti-corrosion materials. The corrosion is a redox reaction proceeding through the local cell mechanism : the iron oxidation half-cell reaction at the local anode and the reduction of oxygen at the local cathode. To prepare a teaching tool for understanding of the mechanism, the visualization of the corrosion was attempted using phenolphthalein and potassium hexacyanoferrate (III) as color couplers for the anodic and cathodic products : Fe2+ and OH-. The local anode and cathode were obviously shown as gradual blue and red coloration when commercial nails were soaked in 4% NaCl aqueous solution containing phenolphthalein and potassium hexacyanoferrate (III) . On the other hand, no coloration occurred for the nail covered with a conductive polymer polyaniline. To know the anti-corrosion mechanism, the open-circuit potential of the nail was measured. The fact that the potential was kept at the potential range where iron was passivated implied that polyaniline acted as an in-situ oxidant. The visualization was experimentally performed at an actual chemistry class and the utility value was estimated. As a result, the visualization is expected to be a useful teaching tool for the corrosion and the understanding of the role of polyaniline as the anti-corrosion material.

  1. Determination of Chlorinity of Water without the Use of Chromate Indicator

    PubMed Central

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


    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

  2. Approaches to flame resistant polymeric materials

    NASA Technical Reports Server (NTRS)

    Liepins, R.


    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.

  3. Quantitative molecular-mixing measurements using digital processing of absorption images

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Schneider, S. P.; Collicott, S. H.


    Absorption imaging was used to measure the chemical product formed in a nonpremixed reacting turbulent water-jet. A collimated light-beam was absorbed by red phenolphthalein formed through a chemical reaction between neutral (pH 7) jet fluid and alkaline tank fluid. The integrated absorption was imaged on a CCD camera. Standard single-point absorption technique was thus extended to allow simultaneous measurement of absorption over a two-dimensional field. Digital image processing techniques were applied to obtain the time-average of the integrated chemical product. Product-concentration profiles in the natural jet were obtained using Abel inversion. The chemical product present six diameters downstream of the jet exit was increased 35 percent by the addition of two tabs.

  4. A novel SWCNT platform bearing DOTA and ?-cyclodextrin units. "One shot" multidecoration under microwave irradiation.


    Calcio Gaudino, E; Tagliapietra, S; Martina, K; Barge, A; Lolli, M; Terreno, E; Lembo, D; Cravotto, G


    The functionalization of single-walled carbon nanotubes (SWCNTs) via microwave-assisted grafting reactions enables efficient multidecoration in a single step. A novel water-soluble SWCNT platform was prepared via the simple 1,3-dipolar cycloaddition of azomethine ylides under dielectric heating. Thanks to a single grafting reaction the CNT surface binds in a 1?:?1 ratio an amino acidic ?-cyclodextrin (?-CD) derivative and the DOTAMA moiety (1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid monoamide). This novel "one shot" synthesis, compared with multistep functionalizations, preserves the SWCNT's structural integrity (TEM images). Besides thermogravimetric analyses, the determination of the amount of ?-CD and DOTA moieties grafting onto the SWCNT's surface was performed on the basis of phenolphthalein and gadolinium complexation, respectively. PMID:24872207

  5. A comparison of the presumptive luminol test for blood with four non-chemiluminescent forensic techniques.


    Webb, Joanne L; Creamer, Jonathan I; Quickenden, Terence I


    Presumptive blood detection tests are used by forensic investigators to detect trace amounts of blood or to investigate suspicious stains. Through the years, a number of articles have been published on the popular techniques of the day. However, there is no single paper that critiques and compares the five most common presumptive blood detection tests currently in use: luminol, phenolphthalein (Kastle-Meyer), leucomalachite green, Hemastix and the forensic light source. The present authors aimed to compare the above techniques with regard to their sensitivity, ease of use and safety. The luminol test was determined to be the most sensitive of the techniques, while Hemastix is a suitable alternative when the luminol test is not appropriate. PMID:16645959

  6. Solid state amorphization of organic molecular crystals using a vibrating mill

    NASA Astrophysics Data System (ADS)

    Tsukushi, Itaru; Yamamuro, Osamu; Matsuo, Takasuke


    The solid-state amorphization of organic molecular crystals was studied by differential scanning calorimetry (DSC) and X-ray powder diffraction. Two clathrate compounds of tri- O-methyl-?-cyclodextrin (TMCD) containing p-nitrobenzoic acid (NBA) and p-hydroxybenzoic acid (HBA), and seven other organic compounds, sucrose (SUC), salicin (SAL), phenolphthalein (PP), 1,3,5-tri-?-naphthylbenzene (TNB), p-quaterphenyl ( p-QP), p-terphenyl ( p-TP) and 1,3,5-triphenylbenzene (TPB) were ground for 2-16 h with a vibrating mill at room temperature. A halo diffraction pattern and exothermic effect due to the crystallization were observed in TMCD-NBA, TMCD-HBA, SUC, SAL, PP and TNB, indicating amorphization of these crystals. The ability of solid-state amorphization in organic molecular crystals was discussed from a thermodynamic point of view.

  7. Structural Relaxations and Thermodynamic Properties of Molecular Amorphous Solids by Mechanical Milling

    NASA Astrophysics Data System (ADS)

    Tsukushi, I.; Yamamuro, O.; Matsuo, T.

    The organic crystals of tri-O-methyl-?-cyclodextrin (TMCD) and its three clathrate compounds containing benzoic acid (BA), p-nitrobenzoic acid (NBA) and p-hydroxybenzoic acid (HBA), sucrose (SUC), salicin (SAL), phenolphthalein (PP), 1,3,5-tri-?-naphthylbenzene (TNB) were amorphized by milling with a vibrating mill for 2 ˜ 16 hours at room temperature. The amorphization was checked by differential scanning calorimetry (DSC) and X-ray powder diffraction. The heat capacities of crystals, liquid quenched glasses (LQG), and mechanically-milled amorphous solid (MMAS) of TMCD and TNB were measured with an adiabatic calorimeter in the temperature range between 12 and 375 K. For both compounds, the enthalpy relaxation of MMAS appeared in the wide temperature range below Tg and the released configurational enthalpy was much larger than that of LQG, indicating that MMAS is more disordered and strained than LQG.

  8. Sequestration of CO2 by concrete carbonation.


    Galan, Isabel; Andrade, Carmen; Mora, Pedro; Sanjuan, Miguel A


    Carbonation of reinforced concrete is one of the causes of corrosion, but it is also a way to sequester CO2. The characteristics of the concrete cover should ensure alkaline protection for the steel bars but should also be able to combine CO2 to a certain depth. This work attempts to advance the knowledge of the carbon footprint of cement. As it is one of the most commonly used materials worldwide, it is very important to assess its impact on the environment. In order to quantify the capacity of cement based materials to combine CO2 by means of the reaction with hydrated phases to produce calcium carbonate, Thermogravimetry and the phenolphthalein indicator have been used to characterize several cement pastes and concretes exposed to different environments. The combined effect of the main variables involved in this process is discussed. The moisture content of the concrete seems to be the most influential parameter. PMID:20225850

  9. Erosive Potential of Sugar Free and Sugar Containing Pediatric Medicines Given Regularly and Long Term to Children

    Microsoft Academic Search

    Ruchi Arora; Utsav Mukherjee; Vivek Arora

    Objective  To assess the erosive potential of 94 pediatric medicines of various therapeutic groups in vitro.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  \\u000a In vitro measurement of endogenous pH and titratable acidity (mmol) of 94 formulations was done. Endogenous pH was measured using\\u000a a pH meter, followed by titration with 0.1-M NaOH using phenolphthalein as indicator.\\u000a \\u000a \\u000a \\u000a \\u000a Results  Overall, 55 (59%) formulations had an endogenous pH of <5.5. The

  10. Carbonation and pH in mortars manufactured with supplementary cementitious materials

    SciTech Connect

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


    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.

  11. Effects of sodium picosulfate and other laxatives in cultured Chang cells.


    Nishikawa, J


    Cytotoxic effects were studied in Chang liver cells exposed to 4,4'-dihydroxy-diphenyl-(2-pyridyl)-methane-bis(hydrogen sulfate) (ether)-disodium salt (sodium picosulfate) and the results were compared with the effects of other laxatives. Sodium picosulfate caused a decrease in cell growth parallel to a decrease in glucose consumption and lactate production at 2000 and 4000 microgram/ml. On the contrary, 4,4'-dihydroxy-diphenyl-(2-pyridyl)-methane (bis-acodyl) decreased cell growth at 25 and 50 microgram/ml, while glucose consumption, lactate production and the molar ratio of glucose converted to lactate were increased. These effects were also observed with 4,4'-dihydroxy-diphenyl-(2-pyridyl)-methane (La 96), 3,3-bis(p-hydroxyphenyl)oxindole (oxyphenisatin acetate) and 3,3-bis(p-acetoxyphenyl) phthalide (phenolphthalein) at doses of 25 and 50 microgram/ml. Diphenolic compounds seem to increase anaerobic glycolysis by inhibition of respiration. This assumption was confirmed with potassium cyanide, which is known to inhibit the electron transport in the respiratory chain. Actinomycin D, cycloheximide and hydroxyurea did not show such effects. PMID:7198466

  12. Application of lipovitellin-salt-mannitol agar for screening, isolation, and presumptive identification of Staphylococcus aureus in a teaching hospital.

    PubMed Central

    Merlino, J; Gill, R; Robertson, G J


    Lipovitellin-salt-mannitol (LSM) plate medium was examined for its ability to directly isolate, recover, and presumptively identify Staphylococcus aureus from 418 clinical specimens. The criteria for medium evaluation included colony morphology reactions, selectivity, and ease of isolation. For 298 specimens used for screening, LSM agar medium was compared with the other conventional media used, mannitol salt agar (MSA), 5% horse blood agar (HBA), and phenolphthalein phosphate agar (PPA), to detect and recover S. aureus and methicillin-resistant S. aureus. The results indicated that LSM agar is more effective than MSA, HBA, or PPA for the recovery and isolation of S. aureus and methicillin-resistant S. aureus. On a replicator multipoint inoculation system, we compared the reactions on LSM agar, MSA, and DNase agar of 227 different strains of staphylococci, which included 178 different strains of S. aureus and 49 different strains of coagulase-negative staphylococci isolated from clinical specimens. By using the lipovitellin precipitation activity and mannitol fermentation characteristics, LSM agar gave a 100% correlation in presumptively identifying S. aureus. LSM agar may be an alternative plate medium for large hospital extensive screening for the detection and isolation of S. aureus. PMID:8940440

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

    PubMed Central

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


    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

  14. Solvothermal synthesis of V{sub 4}O{sub 9} flake-like morphology and its photocatalytic application in the degradation of methylene blue

    SciTech Connect

    Chine, M.K. [Laboratoire de Chimie de la Matière Condensée, IPEITunis, 2 rue Jawaher Lel Nehru 1008, B.P. 229 Montfleury, Tunis (Tunisia)] [Laboratoire de Chimie de la Matière Condensée, IPEITunis, 2 rue Jawaher Lel Nehru 1008, B.P. 229 Montfleury, Tunis (Tunisia); Sediri, F., E-mail: [Laboratoire de Chimie de la Matière Condensée, IPEITunis, 2 rue Jawaher Lel Nehru 1008, B.P. 229 Montfleury, Tunis (Tunisia); Faculté des Sciences de Tunis, Université, Tunis-Elmanar, 2092 Elmanar, Tunis (Tunisia); Gharbi, N. [Laboratoire de Chimie de la Matière Condensée, IPEITunis, 2 rue Jawaher Lel Nehru 1008, B.P. 229 Montfleury, Tunis (Tunisia)] [Laboratoire de Chimie de la Matière Condensée, IPEITunis, 2 rue Jawaher Lel Nehru 1008, B.P. 229 Montfleury, Tunis (Tunisia)


    Highlights: ? Flake-like nanocrystalline V{sub 4}O{sub 9} was synthesized by a solvothermal route. ? Photocatalytic activity has been evaluated by the degradation of methylene blue under visible light irradiation. ? V{sub 4}O{sub 9} nanoflakes exhibited much higher photocatalytic activity two times higher than the bulk V{sub 2}O{sub 5}. -- Abstract: Flake-like nanocrystalline V{sub 4}O{sub 9} has been successfully synthesized by solvothermal process using V{sub 2}O{sub 5} as vanadium source and phenolphthalein as a reducing agent and a structure-directing template. Techniques X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and ultraviolet–visible (UV–vis) spectroscopy have been used to characterize the structure, the morphology and the composition of the material. The photocatalytic activity of the material has been evaluated by the degradation of methylene blue under visible light irradiation. As a result, after the lapse of 150 min, around 93.54% bleaching was observed, with V{sub 4}O{sub 9} nanoflakes yielding more photodegradation compared to that of bulk V{sub 2}O{sub 5}. This presents a degradation percentage of about 44.67%.

  15. Comparison of Salivary Beta Glucuronidase Activity in Chronic Periodontitis Patients with and without Diabetes Mellitus

    PubMed Central

    ND, Jayakumar; Varghese, Sheeja


    Aim of the study: The aim of the study was to estimate the salivary beta glucuronidase (?) activity in patients with chronic periodontitis with and without diabetes mellitus and to evaluate the relationship between Beta Glucuronidase activity and Periodontal clinical parameters. Materials and Methods: The study consisted of 80 patients of both sexes with age ranging from 20-60 years and they were divided into four groups. Clinical parameters such as Gingival index, Probing depth and Clinical attachment loss were measured. Salivary Beta Glucuronidase activity was measured using spectrophotometer with reagents like phenolphthalein glucuronic acid, phosphate and glycine buffer. Results: The mean BG activity of Group IV (1.17 ± 0.27) was significantly higher than mean BGA levels of Group I, II, III. The p-value was < 0.05. The mean BGA levels of Group III (0.78 ± 0.17) was significantly higher than mean BGA levels of Group I, Group II at 5 % level. There was a significant positive linear relationship between salivary ? Glucuronidase level and Probing Depth, clinical attachment level in the experimental Groups. Conclusion: The salivary ? Glucuronidase level was higher in Diabetic patients with periodontitis than nondiabetic periodontitis patients. PMID:25121058

  16. Structure and properties of PVDF membrane with PES-C addition via thermally induced phase separation process

    NASA Astrophysics Data System (ADS)

    Wu, Lishun; Sun, Junfen


    Polyvinylidene fluoride (PVDF) membrane and PVDF membrane with phenolphthalein polyethersulfone (PES-C) addition were prepared via thermally induced phase separation (TIPS) method by using diphenyl carbonate (DPC) and dimethyl acetamide (DMAc) as mixed diluents. The effects of coagulation temperature and pre-evaporation time on structure and properties of membranes were studied. The changes of sewage flux in MBR and the attenuation coefficient of sewage flux were investigated. The resistance distributions of PVDF and PVDF/PES-C membranes were compared by resistance analysis. Membrane composition and structure were characterized by ATR-FTIR, TGA, SEM and AFM. The foulant on membranes was analyzed by FTIR. The contact angle of PVDF/PES-C membrane was lower than that of PVDF membrane. A thinner skin layer and a porous cellular support layer formed in PVDF/PES-C membrane and resulted in a higher porosity and pure water flux. The pure water flux and porosity of PVDF/PES-C membrane increased with rising coagulation temperature and decreased with extending pre-evaporation time. The flux attenuation coefficient, the cake layer resistance and internal fouling resistance of PVDF/PES-C membrane in MBR were smaller than those of PVDF membrane in MBR. The FTIR spectrum of foulant on membrane indicated that the foulant on PVDF/PES-C membrane was mostly composed of protein and polysaccharide, while the foulant on pure PVDF membrane included biopolymer clusters besides protein and polysaccharide.

  17. 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

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


    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.

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

    NASA Astrophysics Data System (ADS)

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


    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.

  19. Highly class-selective solid-phase extraction of bisphenols in milk, sediment and human urine samples using well-designed dummy molecularly imprinted polymers.


    Sun, Xiaoli; Wang, Jincheng; Li, Yun; Jin, Jing; Yang, Jiajia; Li, Fang; Shah, Syed Mazhar; Chen, Jiping


    Dummy molecularly imprinted polymers (DMIPs) towards bisphenols (BPs) were prepared employing 1,1,1-tris(4-hydroxyphenyl)ethane (THPE) and phenolphthalein (PP) as dummy templates. The selectivity of the resulting DMIPs was evaluated by high-performance liquid chromatography (HPLC). Both PP-DMIP and THPE-DMIP showed excellent class selectivity towards bisphenols. THPE-DMIP prepared using the template molecule with three hydroxyphenyl functionalities achieved higher imprinting factors (IF) for the bisphenols over a range of 7.9-19.8. An efficient approach based on dummy molecularly imprinted solid phase extraction (DMISPE) coupled with HPLC-DAD was developed for selective extraction of eight bisphenols in sediment, milk and human urine samples using THPE-DMIP as sorbents. The method showed good recoveries (82-102%) and precision (RSD 0.2-4%, n=3) for these samples spiked at two concentration levels (25 and 250ngg(-1) or ngmL(-1)). The detection limits ranged between 0.6 and 1.1ngg(-1) or ngmL(-1). Efficient removal of sample matrix and interferences was also achieved for these samples after DMISPE process. The results demonstrated great potential of the optimized methods for sample preparation in the routine analysis of trace BPs in complex samples. PMID:25130092

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

    PubMed Central

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


    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

  1. Determination of direct and fugitive PM emissions in a Mediterranean harbour by means of classic and novel tracer methods.


    Moreno, Natalia; Viana, Mar; Pandolfi, Marco; Alastuey, Andrés; Querol, Xavier; Chinchón, Servando; Pinto, Juan Francisco; Torres, Federico; Díez, Juan Manuel; Saéz, José


    Remodelling works are frequent in harbour areas, given that they must adapt to rapidly changing market requirements. Depending on their nature (construction, demolition, etc.), these works may be carried out during long periods of time and thus exert a significant impact on the air quality at the harbours and their surroundings. The air quality at the Valencia harbour was studied during an enlargement project. Four sampling stations aimed to cover the major dust-emitting activities in the harbour. In addition, a sampling campaign was carried out to collect dust materials at their emission sources (e.g., loading and unloading of clinker and petroleum coke, as well as the enlargement works). Differences obtained between PM levels at the monitoring sites were correlated with the distance between sampling stations and enlargement works and/or harbour operations, as well as with the preferential wind direction. In all cases, the days with the highest PM_10 levels were linked to wind directions coinciding with the location of the enlargement works or the clinker and petroleum coke stocks. Classic source apportionment methodologies (PCA and CMB) were applied to the data, but their interpretation was complex due to the similar chemical signatures of PM originating from direct and fugitive emissions from stocked materials (e.g., clinker), and the enlargement works. To overcome this difficulty, a novel non-statistical approach was used to obtain quantitative estimations of the contributions from sources (petroleum coke and clinker), based on the correlation between specific PM components (e.g., carbonaceous species) and source tracers (e.g., V). Finally, a qualitative test using phenolphthalein was devised to identify the presence of clinker on the filters, which provided positive results. This novel tracer approach is thus recommended for harbour authorities. PMID:19716644

  2. Physical Selectivity of Molecularly Imprinted polymers evaluated through free volume size distributions derived from Positron Lifetime Spectroscopy

    NASA Astrophysics Data System (ADS)

    Pasang, T.; Ranganathaiah, C.


    The technique of imprinting molecules of various sizes in a stable structure of polymer matrix has derived multitudes of applications. Once the template molecule is extracted from the polymer matrix, it leaves behind a cavity which is physically (size and shape) and chemically (functional binding site) compatible to the particular template molecule. Positron Annihilation Lifetime Spectroscopy (PALS) is a well known technique to measure cavity sizes precisely in the nanoscale and is not being used in the field of MIPs effectively. This method is capable of measuring nanopores and hence suitable to understand the physical selectivity of the MIPs better. With this idea in mind, we have prepared molecular imprinted polymers (MIPs) with methacrylicacid (MAA) as monomer and EGDMA as cross linker in different molar ratio for three different size template molecules, viz. 4-Chlorophenol (4CP)(2.29 Å), 2-Nephthol (2NP) (3.36 Å) and Phenolphthalein (PP) (4.47Å). FTIR and the dye chemical reactions are used to confirm the complete extraction of the template molecules from the polymer matrix. The free volume size and its distribution have been derived from the measured o-Ps lifetime spectra. Based on the free volume distribution analysis, the percentage of functional cavities for the three template molecules are determined. Percentage of functional binding cavities for 4-CP molecules has been found out to be 70.2% and the rest are native cavities. Similarly for 2NP it is 81.5% and nearly 100% for PP. Therefore, PALS method proves to be very precise and accurate for determining the physical selectivity of MIPs.

  3. Net alkalinity and net acidity 1: Theoretical considerations

    USGS Publications Warehouse

    Kirby, C.S.; Cravotta, C.A., III


    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 problems. Theoretically defined "CO 2-acidity" is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass- action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mg L -1 as CaCO3 (based on pH and analytical concentrations of dissolved FeII, FeIII, Mn, and Al in mg L -1):aciditycalculated=50{1000(10-pH)+[2(FeII)+3(FeIII)]/56+2(Mn)/ 55+3(Al)/27}underestimates contributions from HSO4- and H+, but overestimates the acidity due to Fe3+ and Al3+. However, these errors tend to approximately cancel each other. It is demonstrated that "net alkalinity" is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation, (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the value obtained in a standard method "hot peroxide" acidity titration, provided that labs report negative values. The authors recommend the third approach; i.e., net alkalinity = -Hot Acidity. ?? 2005 Elsevier Ltd. All rights reserved.

  4. In vitro metabolism and identification of human enzymes involved in the metabolism of methylnaltrexone.


    Tong, Zeen; Chandrasekaran, Appavu; Li, Hongshan; Rotshteyn, Yakov; Erve, John C L; Demaio, William; Talaat, Rasmy; Hultin, Theresa; Scatina, JoAnn


    Methylnaltrexone (MNTX) is a peripherally acting mu-opioid receptor antagonist and is currently indicated for the treatment of opioid-induced constipation in patients with advanced illness who are receiving palliative care, when response to laxative therapy has not been sufficient. Sulfation to MNTX-3-sulfate (M2) and carbonyl reduction to methyl-6alpha-naltrexol (M4) and methyl-6beta-naltrexol (M5) are the primary metabolic pathways for MNTX in humans. The objectives of this study were to investigate MNTX in vitro metabolism in human and nonclinical species and to identify the human enzymes involved in MNTX metabolism. Of the five commercially available sulfotransferases investigated, only SULT2A1 and SULT1E1 catalyzed M2 formation. Formation of M4 and M5 was catalyzed by NADPH-dependent hepatic cytosolic enzymes, which were identified using selective chemical inhibitors (10 and 100 microM) for aldo-keto reductase (AKR) isoforms, short-chain dehydrogenase/reductase including carbonyl reductase, alcohol dehydrogenase, and quinone oxidoreductase. The results were then compared with the effects of the same inhibitors on 6beta-naltrexol formation from naltrexone, a structural analog of MNTX, which is catalyzed mainly by AKR1C4. The AKR1C inhibitor phenolphthalein inhibited MNTX and naltrexone reduction up to 98%. 5beta-Cholanic acid 3alpha,7alpha-diol, the AKR1C2 inhibitor, and medroxyprogesterone acetate, an inhibitor of AKR1C1, AKR1C2, and AKR1C4, inhibited MNTX reduction up to 67%. Other inhibitors were less potent. In conclusion, the carbonyl reduction of MNTX to M4 and M5 in hepatic cytosol was consistent with previous in vivo observations. AKR1C4 appeared to play a major role in the carbonyl reduction of MNTX, although multiple enzymes in the AKR1C subfamily may be involved. Human SULT2A1 and SULT1E1 were involved in MNTX sulfation. PMID:20173089