• Title/Summary/Keyword: mixed salt

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An Experimental Study on the Salt Resistance Properties with Concrete Materials under Marine Exposure Environment (I) (해양환경에 폭로한 콘크리트의 내염특성에 대한 실험적 연구 (I))

  • 신도철;김영웅;김용철;김동철
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.51-56
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    • 2002
  • Protection against salt attack in seawater is obtained by using a dense, quality concrete with a low water-cement ratio, and a components appropriate for producing concrete having the needed salt resistance. The objective of this study is to evaluate the feature of corrosion with using the various concrete materials under marine exposure environment. According to the test results, slag powder and anti -corrosion inhibitor showed high chloride resistance effect. Also concre crack have an influence on corrosion of steel in spite of mixed design for salt resistance concrete. The requirement for low permeability is essential not only to delay the effect of salt attack, but also to afford adquate protection to reinforcement with admixtures.

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The Chloride Ion Diffusivity of Ready-Mixed Concrete Depending on Specified Compressive Strength (레디믹스트 콘크리트의 설계기준 압축강도별 염소이온 확산특성)

  • Park, Dong-Cheon;Kim, Yong-Ro
    • Journal of the Korea Institute of Building Construction
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    • v.18 no.6
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    • pp.543-550
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    • 2018
  • The RC buildings which are constructed on the seaside are followed by KBC(2016) to achieve the minimization of durability damage. To control the corrosion of the reinforcing steel bar by salt attack, W/C should be under 0.4 and specified concrete strength is higher than 35MPa in the concrete/building construction standard specification. Even though it has been proved that the concrete mixed with mineral admixture such as blast furnace slag and fly ash etc. have high strength and durability in previous researches, the beneficial informations are not applied to the codes. Ready-mixed concretes which usually include the admixtures in Busan were tested to certify the salt attack durability. In the same specified concrete strength, remarkable salt attack durability was evaluated in comparison to OPC. For economical and reliable durability design, chloride ion diffusivity should be measured before applying to new building construction.

Experimental Study on Physical Properties and Water Absorption Resistance Evaluation of Cement Mortar Incorporating Inorganic Metal Salt-based Water Repellent Powder (무기물 금속염계 발수분체를 혼입한 시멘트 모르타르의 물리적 특성 및 수분흡수저항성에 대한 실험적 연구)

  • Lee, Won Geun;Yoon, Chang Bok
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.4
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    • pp.609-616
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    • 2021
  • In this experimental, water-repellent powder, which is a metal salt-based inorganic substance, and natural zeolite powder, which is a pozzolan-based material, were mixed into cement mortar, and their physical properties and resistance to moisture were confirmed. It was confirmed that the test specimen using natural zeolite at the same time had excellent resistance in the water permeation test and the chloride penetration test as compared with the test specimen in which the inorganic metal salt-based water-repellent powder was mixed alone. When a metal salt-based water-repellent powder is used, it cannot be uniformly dispersed inside water due to its insoluble property, and is limited to the surface. When used at the same time as natural zeolite, the setting time at the initial stage of hydration is fast due to the pozzolan reaction, and the water-repellent powder adheres to the porous of the natural zeolite and is evenly distributed inside the test specimen to generate some water resistance.

Chemical Transformation of Individual Asian Dust Particles Estimated by the Novel Double Detector System of Micro-PIXE

  • Ma, Chang-Jin
    • Asian Journal of Atmospheric Environment
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    • v.4 no.2
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    • pp.106-114
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    • 2010
  • By the application of novel double detector system of micro-PIXE that can detect light elements (Z<14), we made an attempt to provide a thorough discussion on the aging processes of Asian dust (hereafter called "AD") particle by reaction with sea-slat. The elemental spectra and maps obtained from the microbeam radiation of micro-PIXE to individual AD particles were useful for fractionating AD particles into both internally and externally mixed particles. A spatial distribution of elements in a minute domain of single particle obtained by scanning the microbeam irradiation enabled us not only to estimate the chemical mixing state of individual AD particles but also to presume their aging processes in both ambient air and cloud. By calculating the normalized micro-PIXE net count of elements, it was possible to classify individual AD particles into three distinct groups (i.e., (1) Aging type 1: AD particle coated by the gaseous Cl evaporated by the reaction between artificial acids and sea salt; (2) Aging type 2: AD particle mixed with sea salt but no additional reaction with artificial acids; and (3) Non-aged type) A relatively high transformation rate (63.3-75.9%) was shown in large particles (greater than $5.1\;{\mu}m$ in diameter).

Cinnamon Plant Extract as Corrosion Inhibitor for Steel Used in Waste Water Treatment Plants and Its Biological Effect on Escherichia coli

  • Fouda, Abd El-Aziz S.;Nazeer, Ahmed Abdel;El-Khateeb, Ayman Y.;Fakih, Mohamed
    • Journal of the Korean Chemical Society
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    • v.58 no.4
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    • pp.359-365
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    • 2014
  • The inhibition effect of cinnamon plant extract as a green corrosion inhibitor for steel in sulfide polluted salt water was studied by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM). The results showed that cinnamon plant extract in sulfide polluted salt water is a good corrosion inhibitor with inhibition efficiency reached to 80% at 250 ppm of the plant extract. The adsorption of cinnamon obeys Temkin adsorption isotherm, and acts as a mixed-type of inhibitor but dominantly as a cathodic inhibitor in sulfide polluted salt water.

Studies on the Reaction Mechanism of Azo Dyes with Cetyltrimethylammonium Bromide

  • Kim, Bak-Kwang;Sim, Kyl-Soon;Lee, Wang-Kyu
    • Journal of Pharmaceutical Investigation
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    • v.12 no.4
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    • pp.101-111
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    • 1982
  • The effect of salt addition to MO-CTB mixed micelle was studied. The logarithm of cmcs obtained from above experiment is a linear function of the logarithm of the sum of the cmc and the concentration of added salt. In order to investigate the relation of the color change and the structure, the measurement of conductance to the mixed micelle has been carried out. To see the color change and conductance data obtained in the present study, structure A is more probable one to the micelles having the ${\lambda}_{max}$ 376nm.

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Principles of Physiology of Lipid Digestion

  • Bauer, E.;Jakob, S.;Mosenthin, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.282-295
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    • 2005
  • The processing of dietary lipids can be distinguished in several sequential steps, including their emulsification, hydrolysis and micellization, before they are absorbed by the enterocytes. Emulsification of lipids starts in the stomach and is mediated by physical forces and favoured by the partial lipolysis of the dietary lipids due to the activity of gastric lipase. The process of lipid digestion continues in the duodenum where pancreatic triacylglycerol lipase (PTL) releases 50 to 70% of dietary fatty acids. Bile salts at low concentrations stimulate PTL activity, but higher concentrations inhibit PTL activity. Pancreatic triacylglycerol lipase activity is regulated by colipase, that interacts with bile salts and PTL and can release bile salt mediated PTL inhibition. Without colipase, PTL is unable to hydrolyse fatty acids from dietary triacylglycerols, resulting in fat malabsorption with severe consequences on bioavailability of dietary lipids and fat-soluble vitamins. Furthermore, carboxyl ester lipase, a pancreatic enzyme that is bile salt-stimulated and displays wide substrate reactivities, is involved in lipid digestion. The products of lipolysis are removed from the water-oil interface by incorporation into mixed micelles that are formed spontaneously by the interaction of bile salts. Monoacylglycerols and phospholipids enhance the ability of bile salts to form mixed micelles. Formation of mixed micelles is necessary to move the non-polar lipids across the unstirred water layer adjacent to the mucosal cells, thereby facilitating absorption.

The effect on the Rf value by the number of thiocyanate radical in various thiocyanate ammine chromium complex salts (Thiocyanato ammine계 chromium complex salts에 있어 thiocyanato기의 수가 Rf치에 미치는 영향)

  • 최종인
    • YAKHAK HOEJI
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    • v.10 no.4
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    • pp.1-6
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    • 1966
  • Various thiocyanatoammine chromium complex salts are prepared by the known methods and the Rf. value of these complex salts are determined by four developers. These four developers were used in the paper chromatographical work of cobalt complex salts by Yamamoto in 1954. It was also found that the developer A (Ch$_{3}$OH, acetone, NH$_{4}$OH) gave best results of these four developers and the decending development gave better results than ascending development in this experiment. In the case of decending development using developer A, it is found that the Rf. value is increased with the number of thiocyanate radical. The reason of this curious results can be explained that the thiocyanate radical in the complex ion is more active for the organic solvent than ammine radical. Shifting of electrons to the central metal and the charge of the complex ion can also effect ot the Rf. value but much questions are remained for the explanation of the above curious phenomenon. Separation of mixed sample is also studied for various mixture of the above complex salts. In the case of the mixture of hexammine and diammine complex salt, the clear separation is possible but in almost all other mixed sample, the results are not clear. Therefore it can be said that the results of this work can be used in the qualitative analysis of the individual complex salts, except the mixed sample of hexammine and diammine complex salts.

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