• Title/Summary/Keyword: phenolphthalein

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A Case Study on Corrosion Rates of Concrete Sewer Pipes in Housing Sites (주택단지 오수용 콘크리트 흄관의 부식속도 측정 사례)

  • Kim, Young-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.550-553
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    • 2006
  • This study measured corrosion rates for checking and analysis of Hume pipes in the housing sites. According to the result, Concrete pipe is deteriorating for twenty years by hydrogen sulfide(H2S). Investigation method applied phenolphthalein method(depth of neutrality). Phenolphthalein method measured average depth from concrete surface to coloring point by red after spraying phenolphthalein solution. A result of investigation, Life span of Hume pipe in the housing site is investigated of twenty years.

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EFFECTS OF BHA AND ACETAMINOPHEN ON THE BILIARY EXCRETION OF PHENOLPHTHALEIN AND THE HEPATIC GLUCURONIDATION IN MALE RATS

  • Choe, Suck-Young;Lim, Wha-Jae;Rina Yu
    • Toxicological Research
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    • v.9 no.2
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    • pp.133-145
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    • 1993
  • The present study examined the effects of butylated hydroxyanisole (BHA) on acetaminophen (AA)-induced hepatotoxicity in male rats and also examined the effects of these compounds on the biliary excretion of phenolphthalein (PP) and the hepatic glucuronidation. Male Sprague-Da-wley rats were pretreated with BHA (0.75% in diet for 10 days) were given single dose of AA (600mg/kg, ip) and liver function was determined 24 hr later. Serum activity of alanine aminotransferase (ALT) and histopathology were used as indices of hepatotoxicity.

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Algorithms to measure carbonation depth in concrete structures sprayed with a phenolphthalein solution

  • Ruiz, Christian C.;Caballero, Jose L.;Martinez, Juan H.;Aperador, Willian A.
    • Advances in concrete construction
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    • v.9 no.3
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    • pp.257-265
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    • 2020
  • Many failures of concrete structures are related to steel corrosion. For this reason, it is important to recognize how the carbonation can affect the durability of reinforced concrete structures. The repeatability of the carbonation depth measure in a specimen of concrete sprayed with a phenolphthalein solution is consistently low whereby it is necessary to have an impartial method to measure the carbonation depth. This study presents two automatic algorithms to detect the non-carbonated zone in concrete specimens. The first algorithm is based solely on digital processing image (DPI), mainly morphological and threshold techniques. The second algorithm is based on artificial intelligence, more specifically on an array of Kohonen networks, but also using some DPI techniques to refine the results. Moreover, another algorithm was developed with the purpose of measure the carbonation depth from the image obtained previously.

An Analysis and Improvement of the Experiment of the Acid-Base Neutralization Reaction (산-염기 중화반응 실험의 문제점 분석 및 개선 방안)

  • Jeon, Yeong-Hwa;Hong, Lan-Sun;Kang, Young-Jin;Kang, Seong-Joo
    • Journal of the Korean Chemical Society
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    • v.48 no.2
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    • pp.189-194
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    • 2004
  • The aim of this study is to analyze and improve the experiment of the acid-base neutralization reaction described in science textbooks. The problems in the neutralization reaction of NaOH-HCl solution were following; 1) the decoloration of phenolphthalein solution, 2) the color change of the titrated solution during condensation for the confirmation of the salt crystals, 3) the difficulty for the confirmation of the salt crystals. These problems are explained by the structure change of phenolphthalein and the improved experiment is proposed.

Phenolphthalein Solution Discoloration determined by alkali concentration in long-term concrete check surface (장기재령 콘크리트의 할렬면에서 알칼리농도에 의한 페놀프탈레인 용액의 변색)

  • Park, Hyun;Lee, Jong-Rok;Kim, Kwang-Ki;Kim, Woo-Jae;Kim, Jong-Sub;Jung, Sang-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.05a
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    • pp.183-186
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    • 2008
  • Carbonation is measured as Phenolphthalein Solution, it is possible to confirm the scope of alkali through acid and basic reaction. Then, Concrete Basic Reaction is decided according to alkali concentration depending on Potassium Hydroxide Now that Carbonation is gradually produced toward inner side from outer side, with time going by, it doesnt work, to some adequate depth, in as fast time as compulsory facilitating test. Thus, this research thesis made a comparative analysis on concrete phenomenal discoloration borderline following Phenolphthalein Solution, as part of a bid to measure Carbonation. Also, the thesis measured Concrete Alkali Concentration. The result showed that concrete coloring is classified into red and scarlet according to alkali concentration, and into borderline breakpoint of the speckle of scarlet and carbonation reaction. The higher chroma becomes with concrete decolorizing, the higher alkali concentration becomes.

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Assesment of Impaired Depth due to Fire of Mock-up Concrete with 21MPa Using Drying Method After Water Immersion (수중 침지 건조방법을 이용한 21MPa급 Mock-up부재 콘크리트의 화해피해 깊이진단)

  • Lim, Gun Su;Han, Jun Hui;Hyun, Seung Yong;kim, Jong;Han, Min Cheol;Han, Cheon Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.241-242
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    • 2021
  • In this study, we develop the damage depth diagnostic technology of fire damage concrete and propose an method of impaired depth due to fire by drying impaired concrete after immersing. Test results indicated that when assesing impared depth due to fire with the dry method after water immersing, impaired depth was clearly found and furthermore, compared with that by Phenolphthalein method 10 mm of damage depth was additionally identified, which is imposible to asses when Phenolphthalein is applied.

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Assesment of Impaired Depth due to Fire of Mock-up Concrete with 40MPa Using Drying Method After Water Immersion (수중 침지 건조방법을 이용한 40MPa Mock-up부재의 화해피해 깊이진단)

  • Lim, Gun Su;Han, Soo Hwan;Baek, Seung Bok;Kim, Jong;Han, Min Cheol;Han, Cheon Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.245-246
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    • 2021
  • In this study, we develop the damage depth diagnostic technology of fire damage concrete and propose an method of impaired depth due to fire by drying impaired concrete after immersing. Test results indicated that when assesing impared depth due to fire with the dry method after water immersing, impaired depth was clearly found and furthermore, compared with that by Phenolphthalein method 15 mm of damage depth was additionally identified, which is imposible to asses when Phenolphthalein is applied.

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Rapid Analysis of Boric Acid in Nickel Plating Solutions (니켈도금액중의 붕산 신속정량법)

  • 염희택
    • Journal of the Korean institute of surface engineering
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    • v.3 no.1
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    • pp.7-12
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    • 1970
  • Only mannitol or glycerine is generally used for the determination of boric acid in a nickel plating solution in order to make its acidic property so strong that it can be titrated with NaOH. However, these solutions give very amgiguous color change of indicator due to the precipitation of nickel salts . Therefore, only experienced dchemistsorwell trained workimen can accurately confirm the actual end point of the titratiion. For eliminating such interference of nickel salts and easily confirming the end point by any persons , the author attempted to find out a solution which produces no precipitates during the titration in these experiments, and also he tried to funish the reason for ambiguousness in titration. The following results were obtained after many experiments. (1) In any titrations which produce nickel salts such nI(oh)$_2$, the salt is formed umption very approximate to the end point, which shows some error by the consumption of titrant(NaOH) . Then, the pink color of phenolphthalein is absorbed by Ni(OH)$_2$ and the pH jumping at the end pint is also diminished to as little as less than 15% of the total phenophthalein ph range. (2) Known methods by complex salts of citrate,w hich do not produce precipitates of Ni(OH)$_2$, are also not very satisfactory, because, the pH jumping at the end point is only about 35% and the color change of phenolphthalein is form blue-green to purple-blue. (3) New method by complex salts of oxalate were attempted in these experiments. They also did not produce precipitates of Ni(OH)$_2$ and were very satisfactory in color change at the end of point was about 65% and the color change was from blue-green to purpled. In this methods, analytica cost was minimized by the use of less amounts of cheaper chemicals than the conventional citrates complex methods. The mixture of chemicals used was composed methods. The mixture of chemical used was composed of 37g/ι of sodium oxalate(Na$_2$C$_2$O$_4$$.$5H$_2$O), 2g/ι of phenolphthalein, and 400ml /ι of glycerin. The accuracy of analysis was within the error of 0.5%. (4) The procedure of analysis was as follows. One ml of nickel plating solution was taken out and to it were added 20ml of water and 20 ml of the above mixture for the indicator. The solution was titrated with 0.1N NaOH. The quantity of boric acid was calculated by the following equation. Boric acid (g/ι) = 6.184${\times}$F${\times}$ml .

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Geotechnical Characteristics of DCM-Improved Specimen Under Artesian Pressure (피압 작용에 따른 DCM 개량체의 지반공학적 특성)

  • Yun, Dae-Ho;Kim, Yun-Tae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.2
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    • pp.187-195
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    • 2022
  • This study investigated the effect of artesian pressure on mechanical properties of deep cement mixing (DCM)-improved specimens. Various laboratory tests such as unconfined compression test and scanning electron microscope (SEM) were conducted on DCM specimens which curied in a water tank with different artesian pressures. The artesian pressure was determined in consideration of the laboratory scale and the hydraulic gradient in field conditions. Results of experimental tests indicated that unconfined compressive strength, secant modulus, and unit weight of specimen decreased and water content tended to increase as an artesian pressure increased. The stress-strain behavior changed brittle to ductile behaviors as an artesian pressure increased. The outflow water from the water tank reacted with the phenolphthalein solution due to the leaching phenomenon of the improved specimen. SEM analysis also confirmed that a small amount of ettringite was formed between soil particles in the specimens with artesian pressure.