• 제목/요약/키워드: mild solution

검색결과 257건 처리시간 0.024초

Investigation of some Natural Product Extracts as Corrosion Inhibitors for Mild Steel in Acid Mediu

  • Subramania, A.;Sathiya Priya, A.R.;Saravanan, S.;Abdul Nasser, A.J.;Vasudevan, T.
    • Corrosion Science and Technology
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    • 제4권6호
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    • pp.231-235
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    • 2005
  • The inhibitive effect of extracts of tamarind seeds and jackfruit seeds, curry leaves and henna leaves on corrosion of mild steel in 1M HCl solution have been studied by weight loss, potentiodynamic polarization and impedance measurements. Results obtained from the electrochemical techniques were in good agreement with weight loss results. From the weight loss data, the values of surface coverage ($\Theta$) and corrosion rate were calculated. The inhibition efficiency (IE) increased with increasing inhibitor concentration in 1M HCl solution. In all the cases the adsorption of the natural product extracts on the mild steel surface from 1M HCl follows the Langmuir adsorption isotherm relationship. Potentiodynamic polarization studies reveal the fact that all the four natural product extracts act as mixed type inhibitors. The decrease in the inhibition efficiency follows the order: Extracts of jackfruit seed>henna leaves>curry leaves>tamarind seed.

C-EXISTENCE FAMILY AND EXPONENTIAL FORMULA

  • Lee, Young S.
    • Korean Journal of Mathematics
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    • 제11권1호
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    • pp.51-55
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    • 2003
  • In this paper, we show that an exponentially bounded mild C-existence family can be represented by the exponential formula.

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The Effect of Imidazole and 2-Methyl Imidazole on the Corrosion of Mild Steel in Phosphoric Acid Solution

  • Chandrasekara, V.;Kannan, K.;Natesan, M.
    • Corrosion Science and Technology
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    • 제4권5호
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    • pp.191-200
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    • 2005
  • Two azole compounds viz., Imidazole (IM) and 2-Methylimidazole (2-MIM) were studied to investigate their inhibiting action on corrosion of mild steel in phosphoric acid ($H_3PO_4$) solution by mass loss and polarization techniques at 302K-333K. It has been found that the inhibition efficiency of the all inhibitors increased with increase in inhibitor concentration and decreases with increasing temperature and also with increase in acid concentrations. The inhibition efficiency of these compounds showed very good inhibition efficiency. At 0.5% of IM and 2-MIM in 1N and 5N phosphoric acid solution at 302K to 333K for 5 hours immersion period, the inhibition efficiency of 2-Methylimidazole found to be higher than Imidazole. The adsorption of these compounds on the mild steel surface from the acids has been found to obey Tempkin's adsorption isotherm. The values of activation energy ($E{\alpha}$) and free energy of adsorption (${\Delta}G{\alpha}ds$) were also calculated. The plots of log $W_f$ against time (days) at 302K give straight line which suggested that it obeys first order kinetics and also calculate the rate constant k and half life time $t_{1/2}$. Surface was analyzed by SEM and FITR spectroscopy.

우울증(憂鬱症)모델 흰쥐에 대한 조위승청탕(調胃升淸湯)과 fluoxetine의 항우울효과(抗憂鬱效果) 비교 (The effects of Jowiseungchungtang versus fluoxetine in the chronic mild stress model of depression in rats)

  • 류재면;김종우;지상은;김은주;박은혜;황의완
    • 동의신경정신과학회지
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    • 제15권1호
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    • pp.27-41
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    • 2004
  • This study was performed to evaluate the effects of Jowiseungchungtang and fluoxetine in the chronic mild stress(CMS) model of depression in rats. Chronic exposure to mild unpredictable stress was found to depress the consumption of sucrose solution in rats for 5 weeks. These CMS-treated rats were stratified into Jowiseungchungtang group, fluoxetine group and vehicle group. And control rats were also stratified into other CMS-treated group. The change of the consumption of sucrose solution was measured, and open field test were performed to investigate the anti-depression effect of Jowiseungchungtang and fluoxetine. The results were as follows : 1. The consumption of sucrose solution was significantly reversed in Jowiseungchungtang-treated group at 7 week, but there was no significant change in other groups. 2. CMS schedule decreased body weight. Jowiseungchungtang group and fluoxetine group showed significant decrease of body weight after 6 weeks. 3. In open field test, Jowiseungchungtang group and fluoxetine group showed no significant change of exploratory activity.

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치매특별등급 대상자 재가요양관리의 장애요인과 해결방안 - 포커스 그룹 인터뷰 활용 - (The Barriers and Solution of Providing Long-term Care Services at Home for the Beneficiaries with Mild Dementia: A Focus Group Interview)

  • 송미숙;임경숙
    • 한국보건간호학회지
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    • 제30권2호
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    • pp.259-273
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    • 2016
  • Purpose: The purpose of this study was to explore the barriers and solution of providing long-term care (LTC) services at home for the beneficiaries with mild dementia. Methods: The data were collected by interviewing three focus groups consisting of 10 home-visit nurses and analyzed through the analytic process by Morgan and Krueger. Results: The barriers of providing LTC services for clients were identified as follows: inadequateness of the current LTC model for elderly individuals with mild dementia and inappropriateness of the personal environment for home care. The solutions for these barriers were suggested as follows: building up a safe environment for home care and maintaining an appropriate standard utilization plan of LTC service. Conclusion: The current service model for the beneficiaries with mild dementia should be modified in order to provide comprehensive long-term care services based on their complex needs.

NAVIER-STOKES EQUATIONS IN BESOV SPACE B-s,(ℝn+)

  • Jin, Bum Ja
    • 대한수학회지
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    • 제50권4호
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    • pp.771-795
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    • 2013
  • In this paper we consider the Navier-Stokes equations in the half space. Our aim is to construct a mild solution for initial data in $B^{-\alpha}_{{\infty},{\infty}}(\mathbb{R}^n_+)$, 0 < ${\alpha}$ < 1. To do this, we derive the estimate of the Stokes flow with singular initial data in $B^{-\alpha}_{{\infty},q}(\mathbb{R}^n_+)$, 0 < ${\alpha}$ < 1, 1 < $q{\leq}{\infty}$.

축대칭 함몰지형 위를 진행하는 파의 변형에 관한 완경사 방정식의 해석 해 (Analytic Solution to Mild Slope Equation for Transformation of Waves Propagating over an Axi-symmetric Pit)

  • 정태화;서경덕
    • 한국해안해양공학회지
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    • 제18권4호
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    • pp.308-320
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    • 2006
  • 축대칭 함몰지형 위를 진행하는 파에 관한 완경사 방정식의 해석 해를 유도하였다. 함몰지형 내부에서의 수심은 함몰지형 중심으로부터의 거리의 덕에 비례하여 변한다. 변수 분리법을 사용하여 지배 방정식을 상미분 방정식으로 전환하였으며, Hunt(1979)의 근사식을 사용하여 방정식의 계수들을 양함수의 형태로 변환하였다. 마지막으로 Frobenius 급수를 사용하여 해석 해를 유도하였다. Hunt 근사식의 특성 상 본 연구에서 유도된 해석 해는 천해와 심해에서는 정확하고 중간수심에서는 덜 정확하다. 해석 해의 타당성을 검토하기 위하여 수치 모델 결과와 비교하였다. 또한 해석 해를 이용하여 함몰지형의 형상과 상대수심 등을 변화시키면서 다양한 조건에 대한 파랑 변형을 검토하였다.

MILD SOLUTIONS FOR THE RELATIVISTIC VLASOV-KLEIN-GORDON SYSTEM

  • Xiao, Meixia;Zhang, Xianwen
    • 대한수학회보
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    • 제56권6호
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    • pp.1447-1465
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    • 2019
  • In this paper, the relativistic Vlasov-Klein-Gordon system in one dimension is investigated. This non-linear dynamics system consists of a transport equation for the distribution function combined with Klein-Gordon equation. Without any assumption of continuity or compact support of any initial particle density $f_0$, we prove the existence and uniqueness of the mild solution via the iteration method.