• Journal of the Korea Institute of Building Construction
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• v.24 no.4
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• pp.413-424
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• 2024

To expedite construction of small precast concrete buildings using dry joints, this study developed and evaluated a connector system for solid slabs. The research included a comprehensive literature review on seismic design requirements for precast concrete floors, followed by an analytical evaluation of the connector's bearing capacity in 3-story buildings. Experimental assessments were conducted to determine the in-plane and out-of-plane capacities of the newly designed semi-circular connector. Finally, the constructability of both the semi-circular and flat connector configurations was compared through tests on single-story precast concrete frames.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.188.2-188
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• 1976

E. coli B 및 E. coli K-12의 Ion 변리주는 저중의 UV 조사에 의해 확산 및 단백질 합성은 그대로 지속되나 세포분열능은 상실되어 격막이 없는 다핵의 filament를 형성하므로 한무배지상에서 colony가 형성되지 않는다. 이와같은 균에 동일균 또는 타의 균체추출액을 가하어 주므로써 세포분열은 재개되며 그 활성물질중 $\beta-NAD가$ 중요한 인자로 작용함은 이미 발표되었으며 본보에서는 NAD 이외의 고분자활성물질에 대해 보고코저 한다.(중략)

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.296-300
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• 2009

Generation of chlorine dioxide ($ClO_2$) was studied by the un-divided electrochemical cell system using $RuO_2$ anode material. Sodium chlorite ($NaClO_2$) was used as a precursor compound of chlorine dioxide. Effect of various operating parameters such as feed solution flow rate, initial solution pH, $NaClO_2$ and NaCl conc., and applied current density on the produced chlorine dioxide concentration and solution pH were investigated in un-divided electrochemical cell system. Produced chlorine dioxide concentration and solution pH were strongly depends on the initial solution pH and feed solution flow rate. Sodium chloride (NaCl) was not only good electrolyte, it was also used as a raw material of chlorine dioxide with $NaClO_2$. Observed optimum conditions were flow rate of feed solution (90 mL/min), initial pH (2.3), $NaClO_2$ concentration (4.7 mM), NaCl concentration (100 mM), and current density ($5A/dm^2$). Produced chlorine dioxide concentration was around 350 mg/L and solution pH was around 3.

• Tuberculosis and Respiratory Diseases
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• v.40 no.4
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• pp.378-383
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• 1993

Background: In recent reports, it has been reported that increased coagulation and decreased fibrinolytic activity has been responsible for abnormal fibrin turnover in exudative pleural effusion. In the cases of empyema, the fibrinopurulent stage is characterized by the fibrin deposition resulting in formation of limiting membranes in the visceral and parietal pleura. Recently attention has been focused on intrapleural fibrinolytic therapy capable of removing intrapleural fibrin deposits by urokinase (UK) in the treatment of empyema. However, these clinical trials have provided the clinical evidences for resolution of pleural loculation after intrapleural urokinase injection (UK-injection), the profiles of fibrinolytic activity following the treatment were still not investigated. Therefore in order to demonstrate the fibrinolytic evidences behind the clinical efficacy of intracavitary UK-injection, we examined intrapleural plasminogen activator activity (PA-activity) and D-dimer (D-Di) concentrations before and after each repeated UK-injection into the pleura in subjects with loculated empyema cavity. Methods: In a group of 14 patients with multiple loculated empyema cavity, PA-activity and D-Di concentrations were measured before and after repeated UK-injection. One hundred thousand IU of UK was injected at each time and all sujects had at least two times of UK injection accoring to clinical decisions. Nine out of 14 sujects had three times of UK-injection. Results: The mean (${\pm}SE$) PA-activity prior to treatemnt was $10.5{\pm}7.0$ and it was increased to $91.9{\pm}27.0,\;432.3{\pm}177.1,\;170.0{\pm}85.3$ IU tPA/ml after first, second and third time of UK-injection respectively (p<0.01). D-Di concentrations were also increased from $4.16{\pm}1.06{\times}10^5$ to $9.62{\pm}1.54{\times}10^5,\;12.31{\pm}1.89{\times}10^5,\;8.54{\pm}1.56{\times}10^5$ ng/ml in the same order as above (p<0.05). Conclusion: The suppressed fibrinolytic activity in the empyema cavity get removed sinificantly after inrracavitary injection of urokinase by generation of additional intrapleural plasmin.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.73-80
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• 2007

Biofilm media was equipped in two-compartmented wastewater treatment bioreactor which was separated by porcelain septum. DC 2.0 volt of electric potential was charged to anodic (oxidative) biofilm media (ABM) to induce oxidation potential but not to that of carbon (neutral) biofilm media (CBM) that was used for control test. Biofilm structure, biomass variation, Off variation and wastewater treatment efficiency in the bioreactor equipped with ABM (ABM-bioreactor) and CBM (CBM-bioreactor). Time-coursed variation of biofilm structure forming on surface of ABM and CBM was observed by scanning electron microscopy. The biofilm growing on ABM was dispersed on surface and was not completely covered the media but the biofilm growing on CBM was continuously increased and finally covered the media. The ORP of CBM was decreased to 100 mV, which was reciprocally proportional to the biomass growth. However, the ORP of ABM was about 800 mV, which was maintained during operation for about 60 days. The treatment efficiency of COD in the ABM bioreactor was 2 times higher than those in the CBM bioreactor. From these results, we proposed that electrochemical oxidation potential charged to biofilm media may inhibit formation of biofilm extremely condensed and activate bacterial cell metabolism.