• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.590-596
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• 2012

Enhanced coagulation is best available technologies to treat NOM in water to produce clean drinking water. In this research, the comparison experiments between conventional coagulation (CC) and enhanced coagulation (EC) using 4 type coagulants i.e., ferric chloride, aluminium sulphate (alum), poly aluminium sulphate organic magnesium (PSOM) and poly aluminium chloride (PACl) were performed in terms of surrogate parameters such as dissolved organic carbon (DOC), trihalomethane formation potential (THMFP), haloacetic acid formation potential (HAAFP) and zeta potential variation in order to find out the most effective coagulant and conditions to fit Nakdong River water. When applied to EC process, the turbidity removal efficiency did not increased gradually compared to the CC process when adding coagulants. Furthermore, the removal efficiency of turbidity became decreased much more as coagulants were added increasingly whereas the removal efficiency of DOC, THMFP and HAAFP became increased by 13~18%, 9~18% and 9~18% respectively compared to the CC process. The characteristics of turbidity removal showed relatively high removal efficiency considering the pH variation in entire pH range when using $FeCl_3$ and PACl. Additionally, in case of alum and PSOM steady removal efficiency was shown between pH 5 and pH 8. In terms of DOC surrogate the coagulants including 4 type coagulants indicated high removal efficiency between pH 5 and pH 7. The removal efficiency of dissolved organic matter (DOM) in EC between less than 1 kDa and more than 10 kDa augmented by 11~21% and 16% respectively compared to the CC process. The removal efficiency of hydrophobic and hydrophilic organic matter proved to be increased by 27~38% and 11~15% respectively. In conclusion, the most effective coagulant relating to EC for Nakdong River water was proved to be $FeCl_3$ followed by PSOM, PAC and alum in order.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.5
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• pp.732-737
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• 2012

The aim of this study is examine the protection effect for artery and antithrombotic effect of Sokmyong-tang(SMT; xuming-tang) on carotid artery thrombosis in a rat model. Thirty minutes before $FeCl_3$ treatment, SD rats were intraperitoneal injected with SMT. We tested the effects of SMT on time to occlusion (TTO) in thrombosis model by induced $FeCl_3$ using the laser Doppler flow meter and accessed thrombus weight (TW) inhibition and measured collagen fibers in the vessel after injury using Masson's trichrome stain. SMT(100 mg/kg, i.p.) showed significantly delayed TTO ($13.17{\pm}1.33$ min, P < 0.001) compared to vehicle control group ($8.63{\pm}0.92$ min) and inhibiting effect on TW with $0.72{\pm}0.02$ mg/mm (P < 0.05). In addition, SMT prevented collagen fibres damage in injured vessel ($22.24{\pm}4.48%$, P < 0.001). These results provide experimental evidence for SMT can be used to prevent vascular injury and thrombosis such as hypertension, arteriosclerosis, and so on.

• Korean Journal of Microbiology
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• v.20 no.3
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• pp.119-124
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• 1982

As a basic study to elucidate nutritional physiology and composition of synthetic medium of red rotting bacteria, Erwinia carotovora, of ginseng, the effects of hydrogen ion concentration, various kinds of carbon sources, nitrogen source, micrometallic salts and it's concentration on the gorwth of the bacteria were investigated and the results were as follows. Optimal pH in the basal medium for the growth of the bacteria was 6.5. After incubation the pH in culture media was neutralized. Among the various kinds of carbon sources, sucrose, glucose mannitol, but organic acids were not utilized effectively as nutrients. After incubation the pH turned acidic. Alanine as organic nitrogen sources nad ammonium sulfate as inorganic nitrogen promoted the growth, but L-valine and sodium nitrite were the least effective. Ferric chloride 1.0mg/dl and ferrous sulfate 100mg/dl were the most effective as micrometallic sources. Control and boric acid were the least effective. New synthetic medium based on the above results was follows ; Alanine 1.0g, $KH_2PO_4\;1.0g, \;sucrose\;30.0g, \;MgSo_4{\cdot}7H_2O\;0.5g, \;FeCl_3{\cdot}6H_2O\;1.0mg\;thiamine\;200{\gamma}g$, and distilled water 1000ml, pH6.5.

• Membrane Journal
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• v.7 no.3
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• pp.150-156
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• 1997

The particle back transport velocity from the membrane surface were evaluated to determine the critical flux. Four kinds of back transport mechanisms were considered, i.e. back diffusion, shear induced migration, lateral migration, and interaction enhanced migration. The interaction enhanced migration caused by electrostatic repulsion between particles and membrane surface was found to be the most important mechanism of particle back transport for the charged particles of 0.1 ~10${\mu}{\textrm}{m}$ diameter with 20 to 40 mV of zeta potential. Hematite particles with different sizes were synthesized with ferric chloride (FeCl$_3$) and hydrochloric acid (HCl) at high temperature, and subsequently experimental critical fluxes for each sized particle were obtained. The experimental results were well coincident with the calculated critical fluxes based on back transport mechanisms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1736-1743
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• 2013

The purpose of this study is to investigate the effects of 80% ethanol grape leaf extract (VGLE) and resveratrol (VGLR) from Vitis romaneti on antioxidant of red blood cells (RBC) of rat and efficacy of blood flow improvement in a rat model of topical ferric chloride ($FeCl_3$)-induced carotid artery damage. RBC oxidative hemolysis and plasma lipid peroxidation induced by the aqueous peroxyl radical generator 2,2'-azobis(2-amidinopropane) dihydrochloride were significantly suppressed by VGLE or VGLR in a dose-dependent manner. The $FeCl_3$ treatment seriously damaged the carotid artery: the walls of the artery and blood flow. However, VGLE or VGLR administration has ameliorated the blood flow and suppressed thrombus in blood vessels. These results suggest that VGLE or VGLR ameliorates the oxidative stress of RBC and thrombosis against blood vessel damage.

• Corrosion Science and Technology
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• v.2 no.1
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• pp.18-25
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• 2003

Effects of the precipitation of $\sigma$ phase on the metastable pitting as a precursor of stable pitting corrosion and also on the progress of stale pitting of the 25Cr-7Ni-3Mo-0.25N duplex stainless steel were investigated in chloride solution. Electrochemical potential and current noises of the alloy were measured in 10 % ferric chloride solution ($FeCl_3$) with zero resistance ammeter (ZRA), and then analyzed by power spectral density (PSD) and by corrosion admittance ($A_c$) spectrum. With aging at $850^{\circ}C$, the passive film of the alloy was found to get significantly unstable as represented by power spectral density (PSD) and a transition from metastable pitting state to stable one was observed. In the corrosion admittance spectrum, the number of negative $A_c$ corresponding to the state of localized corrosion increased with aging, suggesting that the precipitation of $\sigma$ phase considerably degraded the passive film by depleting Cr and Mo around it at $\alpha/\sigma$ or $\gamma/\sigma$ phase boundaries, thereby leading to the initiation of the pitting corrosion. However, the Cr and Mo at $\alpha/\sigma$ or $\gamma/\sigma$ phase boundaries which were once depleted due to the precipitation of the $\sigma$ phase were partly replenished by the diffusion of Cr and Mo from the surrounding matrix with aging time longer. The initiation of pitting seems to be associated with the precipitation density of the $\sigma$ phase with an effective size needed to induce the sufficient depletion of Cr and Mo around it.

• Resources Recycling
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• v.17 no.5
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• pp.37-43
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• 2008

Stripping experiments of iron from the loaded Alamine336 by sulfurous, chloric and sulfuric acid solutions have been performed by varying the concentration of acid and stripping conditions. The stripping percentage of iron decreased with the increase of HCl and $H_{2}SO_4$ concentration, while that increased with the increase of $H_{2}SO_3$ concentration up to 3 M. Stripping temperature had adverse effect on the stripping percentage of iron in the stripping by $H_{2}SO_3$ solution, while the stripping percentage of iron by HCl solution increased with the increase of temperature. Stripping isotherm of iron by 0.1 M HCl and 0.1 M $H_{2}SO_4$ solution indicated that three and four stripping stages could result in a solution containing 0.05 M iron at an O/A ratio of 1/10 from the loaded Alamine336 phase where iron concentration was 0.5 M.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.30-34
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• 2006

The wastewater was quickly and fastly cleared by the peel extracts of astringent persimmon fruits. The degree of clearness increased with increasing concentrations (400-600 mg/l) of the peel extracts of astringent persimmon fruits. The removal rates of T-P and CODcr in wastewater with lime and the peel extracts of astringent persimmon fruits were lower than ferric chloride and aluminium sulfate at 100-200 mg/l concentration but higher at above 300 mg/l concentration. The removal rate of T-P increased with increasing concentration of the peel extracts of astringent persimmon fruits.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.4
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• pp.285-292
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• 2021

Osmotic power is to produce electric power by using the chemical potential of two flows with the difference of salinity. Water permeates through a semipermeable membrane from a low concentration feed solution to a high concentration draw solution due to osmotic pressure. In a pressure retarded osmosis (PRO) process, river water and wastewater are commonly used as low salinity feed solution, whereas seawater and brine from the SWRO plant are employed as draw solution. During the PRO process using wastewater effluent as feed solution, PRO membrane fouling is usually caused by the convective or diffusive transport of PRO which is the most critical step of PRO membrane in order to prevent membrane fouling. The main objective of this study is to assess the PRO membrane fouling reduction by pretreatment to remove organic matter using coagulation-UF membrane process. The experimental results obtained from the pretreatment test showed that the optimum ferric chloride and PAC dosage for removal of organic matter applied for the coagulation and adsorption process was 50 mg/L as FeCl₃ (optimum pH 5.5). Coagulation-UF pretreatment process was higher removal efficiency of organic matter, as also resulting in the substantial improvement of water flux of PRO membrane.