• Title/Summary/Keyword: mild solution

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The Effect of Temperature on the Corrosion of Mild Steel in H3PO4 Containing Halides and Sulfate Ions

  • Chandrasekaran, V.;Kannan, K.;Natesan, M.
    • Corrosion Science and Technology
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    • v.4 no.1
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    • pp.8-14
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    • 2005
  • The corrosion behaviour of mild steel in phosphoric acid solution in the presence and absence of pollutants viz. Chloride, Fluoride and Sulfate ions at 302K-333K was studied using mass loss and potentiostatic polarization methods. The addition of chloride and sulfate ions inhibits the mild steel corrosion in phosphoric acid while fluoride ions stimulate it. The effect of temperature on the corrosion behaviour of mild steel indicated that inhibition of chloride and sulfate ions decreased with increasing temperature. The adsorption of these ions (Chloride and sulfate) on the mild steel surface in acid has been found to obey Langmuir adsorption isotherm. The values of activation energy (Ea) and free energy of adsorption ($\Delta$) indicated physical adsorption of these ions (chloride and sulfate) on the mild steel surface. The plot of $logW_{f}$ against time (days) at 302K gives a straight line, which suggested that it obeys first order kinetics and also calculate the rate constant k and half-life time $t_{1/2}$.

The Solution of Mild-Slope Equation using Power Series (멱급수를 이용한 완경사 방정식의 해)

  • Jung, Tae-Hwa;Lee, Seung-Oh;Park, Jin-Ho;Cho, Yong-Sik
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.1
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    • pp.133-138
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    • 2008
  • To analyze incident waves traveling from the deep ocean is very important in that it is based on resolving problems occurred in coastal areas. In general, numerical models and analytical solutions are used to analyze wave transformation. Although a numerical model can be applied to various bottoms and wave conditions, it may have some cumbersome numerical errors. On the other hand, an analytical solution has an advantage of obtaining the solution quickly and accurately without numerical errors. The analytical solution can, however, be utilized only for specific conditions. In this study, the analytical solution of the mild-slope equation has been developed. It can be applied to various conditions combing a numerical technique and an analytical approach while minimizing the numerical errors. As a result of comparing the obtained solutions in this study with those of the previously developed numerical model, A good agreement was observed.

The Effects of Myrtle (Myrtus communis) and Clindamycin Topical Solution in the Treatment of Mild to Moderate Acne Vulgaris: A Comparative Split-Face Study

  • Salmanian, Mahboobeh;Shirbeigi, Laila;Hashem-Dabaghian, Fataneh;Mansouri, Parvin;Azizkhani, Mohammad;Alavi, Shiva;Ghobadi, Ali
    • Journal of Pharmacopuncture
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    • v.23 no.4
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    • pp.220-229
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    • 2020
  • Objectives: Although Acne vulgaris is a chronic skin disease, which its standard treatment causes therapeutic limitations and some common adverse effects, medicinal plants can be effective in treatment with low adverse effects as combination therapy. Myrtle (Myrtus Communis) has some beneficial properties, which has been administered topically and orally for some skin diseases in Persian medicine. This study aimed to compare the efficacy and safety of Myrtle formula and 1% clindamycin topical solution. Methods: This was a split-face clinical trial that was done on 55 patients with mild to moderate acne vulgaris for 16 weeks. The patients received topical Myrtle solution to the right side of the face (group 1) and clindamycin solution to the left side (group 2) twice daily for 12 weeks. All participants were examined for the acne severity index (ASI) and total acne lesions counting (TLC) at certain times during the study. Then, they stopped using them for four weeks. They also did not take the drug in the final four weeks of the study. Results: Forty-eight patients completed the study for 16 weeks; 40 (83.2%) patients were female and the rest of them were male. The mean age and standard deviation were 25.62 ± 7.62 years. After 12 weeks, the percentage changes of comedones, inflammatory lesions, ASI and TLC were significantly reduced in both groups (p < 0.001). The percentage change of inflammatory lesions and ASI decrease was significantly higher in the group 1 (p = 0.03). There was no significant difference in the incidence of side effects between the two groups. There was a more significant decrease in sebum percentage change in the group 1 (p = 0.003). Conclusion: Myrtle lotion was effective and safe for the treatment of mild to moderate acne vulgaris.

UPPER AND LOWER SOLUTION METHOD FOR FRACTIONAL EVOLUTION EQUATIONS WITH ORDER 1 < α < 2

  • Shu, Xiao-Bao;Xu, Fei
    • Journal of the Korean Mathematical Society
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    • v.51 no.6
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    • pp.1123-1139
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    • 2014
  • In this work, we investigate the existence of the extremal solutions for a class of fractional partial differential equations with order 1 < ${\alpha}$ < 2 by upper and lower solution method. Using the theory of Hausdorff measure of noncompactness, a series of results about the solutions to such differential equations is obtained.

Solution Comparisons of Modified Mild Slope Equation and EFEM Plane-wave Approximation (수정 완경사파랑식과 EFEM 평면파 근사식의 해 비교)

  • Seo, Seung-Nam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.2
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    • pp.117-126
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    • 2009
  • In order to test the accuracy between the modified mild slope equation (MMSE) without evanescent modes and the plane-wave approximation (PA) of eigenfunction expansion method, various numerical results from both models are presented. In this study, analytical solutions of two models are employed, one based on the MMSE derived by Porter (2003) and the other on the scatterer method of PA by Seo (2008a). Judging from direct comparisons against existing results of rapidly varying topography, the PA model gives better predictions of the wave propagation than the MMSE model.

EXITSENCE OF MILD SOLUTIONS FOR SEMILINEAR MIXED VOLTERRA-FREDHOLM FUNCTIONAL INTEGRODIFFERENTIAL EQUATIONS WITH NONLOCALS

  • LEE, HYUN MORK
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.3
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    • pp.365-375
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    • 2015
  • Of concern is the existence, uniqueness, and continuous dependence of a mild solution of a nonlocal Cauchy problem for a semilinear mixed Volterra-Fredholm functional integrodifferential equation. Our analysis is based on the theory of a strongly continuous semigroup of operators and the Banach fixed point theorem.

EXISTENCE RESULTS FOR NEUTRAL FUNCTIONAL INTEGRODIFFERENTIAL EQUATIONS WITH INFINITE DELAY IN BANACH SPACES

  • Chandrasekaran, S.;Karunanithi, S.
    • Journal of applied mathematics & informatics
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    • v.33 no.1_2
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    • pp.45-60
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    • 2015
  • This paper is concerned with the existence of mild solutions for partial neutral functional integrodifferential equations with infinite delay in Banach spaces. The results are obtained by using resolvent operators and Krasnoselski-Schaefer type fixed point theorem. An example is provided to illustrate the results.