We investigated the pharmacokinetics of ferulic acid, a potential antioxidant agent, after intravenous (i.v.) bolus administration in rats. To analyze ferulic acid levels in the plasma, bile, urine and tissue samples, we developed an HPLC-based method which was validated for a pharmacokinetic study by suitable criteria. After i.v. bolus administration of ferulic acid, it rapidly disappeared from blood circulation within 15 min. The mean plasma half-lives at α phase (t1/2α) when administered at doses of 2 and 10 mg/ kg were 1.10 and 1.39 min, respectively. The values of t1/2β at the corresponding doses increased 40% (from 5.02 to 7.01 min) with increasing doses. The total body clearance (CLt) values significantly decreased as the ferulic acid dose increased. On the other hand, steady-state volume of distribution (Vdss) values did not show the significant difference with the increase in dose. Of the various tissues, ferulic acid mainly distributed to the liver and kidney after i.v. bolus administration. The ferulic acid concentrations in various tissues at 2 hr after i.v. bolus administration were below 1.0 μg/g tissue. Ferulic acid was excreted in the bile and urine after i.v. bolus administration at the dose of 10 mg/kg. The cumulative amount of ferulic acid in the bile 2 hr after dosage was comparable with the amount excreted in the urine after 72 hr, indicating that i.v. administered ferulic acid was mainly excreted in the both bile and urine. In conclusion, ferulic acid was rapidly cleared from the circulating blood and transferred to tissues such as the liver and kidney after i.v. bolus administration. Moreover, the majority of ferulic acid appears to be excreted in the bile and urine after i.v. bolus administration.

강도 한계상태 설계에서는 균열이 일어난 이후 철근콘크리트 부재의 인장영역에서 철근이 모든 인장력을 부담하는 것으로 가정한다. 그러나 균열 사이의 콘크리트가 실제 콘크리트 부재에서는 특히 사용하중 수준에서의 어느 정도의 인장 응력을 견디는데, 일조 하는 것으로 보고 있다. 이러한 효과를 Tension stiffening 효과라 한다. 본 연구에서는 Tension stiffening 모델과 고강도 철근 콘크리트 보의 휨 실험결과의 비교를 통해 해석모델의 유효성을 평가 하고자 한다. 이를 통해 선정 된 6가지의 Tension stiffening 모델과 실험에 의한 모멘트-곡률, 하중-처짐등을 관계를 평가하였다. 실험결과 설계기준에서는 ACI 318이 Tension stiffening 모델에서는 Owen & Damjanic이 실험 값과 가장 적은 오차율을 보이며 높은 신뢰도를 보였다.