• Membrane and Water Treatment
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• v.5 no.3
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• pp.207-219
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• 2014

Fouling is one of the critical factors associated with the application of membrane technology in treating palm oil mill effluent (POME), due to the presence of high concentration of solid organic matter, oil, and grease. In order to overcome this, chemical cleaning is needed to enhance the effectiveness of membranes for filtration. The potential use of sodium hydroxide (NaOH), sodium chloride (NaCl), hydrochloric acid (HCl), ethylenediaminetetraacetic acid (EDTA), and ultrapure water (UPW) as cleaning agents have been investigated in this study. It was found that sodium hydroxide is the most powerful cleaning agent, the optimum conditions that apply are as follows: 3% for the concentration of NaOH, $45^{\circ}C$ for temperature solution, 5 bar operating pressure, and solution pH 11.64. Overall, flux recovery reached 99.5%. SEM images demonstrated that the membrane surface after cleaning demonstrated similar performance to fresh membranes. This is indicative of the fact that NaOH solution is capable of removing almost all of the foulants from PES membranes.

• Journal of Yeungnam Medical Science
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• v.12 no.1
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• pp.124-134
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• 1995

It is the most important to select optimal culture conditions to promote safe embryo growth in the technique of human in vitro fertilization and embryo transfer. It has been shown that the addition of biologic fluids, such as blood serum, of various origins, improved fertilization and early cleavage rates in numerous species. The purpose of this study is to attempt to measure developmental potential of mouse eggs fertilized and cleaved in Ham's F10 culture medium containing a chelating agent, EDTA and fetal cord serum. In this study, we selected 40 female mice and 20 male mice, and investigated optimal serum concentrations for mouse embryo growth. Two cell stage mouse embryos were cultured in Ham's F-10 medium, Ham's F-10 medium with various concentrations of EDTA, or Ham's F-10 medium with EDTA and 10% human cord serum. Developmental ratios to morula in Ham's F-10 medium containing various concentrations of EDTA and/or 10% fetal cord serum were significantly higher than in unsupplemented Ham's F-10 medium (p<0.05). Developmental ratios to blastocyst in Ham's F-10 containing 10% fetal cord serum and $50{\mu}M$ or $100{\mu}M$ EDTA were significanltly higher than in unsupplemented Ham's F-10 medium (p<0.05). Developmental ratios to morula in Ham's F-10 containing 10% fetal cord serum and $100{\mu}M$ EDTA were significanltly higher than in Ham's F-10 with 10% fetal cord serum used commonly in many human IVF centers(p<0.05). Developmental ratio to blastocyst in Ham's F-10 containing 10% fetal cord serum and $100{\mu}M$ EDTA was significanlty higher than in Ham's F-10 with $200{\mu}M$ EDTA(P<0.05). In summary, embryo development to morula and blastocyst was significanlty higher in the presence of human cord serum or EDTA than in the unsupplemented medium. The most significanly development to morula and blastocyst was obtained at Ham's F-10 medium with $100{\mu}M$ concentration of EDTA and 10% fetal cord serum. These results suggest that Ham's F-10 medium containing 10% fetal cord serum and optimal concentrations of EDTA significantly promoted early cleavage of mouse zygotes, and these will be useful as basic data for the selection of culture medium in human in vitro fertilization.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.767-772
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• 2011

The purpose of this study was to find out required time for recovery of nutritional disorder by Fe-DTPA treatment in induced Fe-deficient tomato cultivars and to select stable Fe-chelate in high pH of nutrient solution. The pH levels of nutrient solution were amended with 6.0, 7.0, and 8.0. Then Fe-EDTA (Ethylenediaminetetraacetic acid, ferric-sodium salt), Fe-DTPA (Sodium ferric diethylenetriamine pentaacetate), and Fe-EDDHA (Ethylenediamine-N,N-bis (2-hydroxyphenylacetic acid) ferric-sodium salt)) were treated as Fe $2.0mg\;L^{-1}$ concentration. The Fe-DTPA and Fe-EDDHA were stable in the nutrient solution of pH 6.0~8.0 but Fe-EDTA in nutrient solution of pH 8.0 was to become insoluble by 25%. The Fe $2.0mg\;L^{-1}$ as Fe-DTPA was treated for recovery of Fe deficient tomato seedlings. In case of Redyoyo and Supersunroad cultivars, total chlorophyll and Fe contents of leaves were recovered as much as those of normal leaves in 5 days. The Rafito cultivar for complete recovery was taken 7 days. When Fe $2.0mg\;L^{-1}$ as Fe-DTPA was supplied to Fe-deficient tomato seedlings, in geotype, heme oxigenase recovered as much as normal leaves in 24 hours in the Rafito and Redyoyo. However, it was not remarkable difference by elapsed time in the Supersunroad.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.271-278
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• 2009

The attempts to develop natural antioxidants have been made with aerial part of 16 Compositae species by analyzing their phenolic compound contents, scavenging activities on 1,l-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals, ferrous ion chelating effects and inhibition effects on peroxidation of linoleic acids. Total polyphenol and flavonoid contents were highest in Matricaria recutica. Scavenging activity on DPPH and ABTS radicals were highest with extracts of Echinacea angustifolia and Serratula coronata var. insularis f. insularis, respectively. Aerial palt extracts of all species showed lower DPPH scavenging activity than ascorbic acid and 2,6-Di-tert-butyl-4-methylphenol (BHT). But Serratula coronata var. insularis f. insularis demonstrated higher ABTS scavenging activity than ascorbic acid and BHT. In Hieracium pilosella, Echinacea angustifolia, Matricaria reculica extracts showed higher ABTS scavenging activity than BHT. Ferrous ion chelating effects was highest with Matricaria recutica extract, but the effects were much lower than ethylenediaminetetraacetic acid (EDTA). The inhibition activity in lipid peroxidation of linoleic acids was highest in Eupatorium japonicum with 90.06% inhibition 4 days after reaction and 40.52% after 24 days. This demonstrated higher inhibition activity and longer lasting than BHT. Aerial part of Matricaria recutica for extraction source, rather than flower, has higher potential for antiox.idant material. In conclusion, development of natural antioxidants in Compositae is possible by studying antioxidant activity of each species.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.122-129
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• 1994

The role of metal ions for the activity of the mitochondrial $F_1-ATPase$ was studied. Removal of non-heme iron ion from the mitochondria by dialysis against chelating agents, 10 mM ethylenediaminetetraacetic acid(EDTA) and 10 mM o-phenanthroline(o-Phe), led to 56% and 49% inactivation of the enzyme, respectively. The enzyme dialyzed against EDTA was reactivated 81% by the addition of 0.5 mM $Fe^{3+}$ and 70% by 0.5 mM $Mg^{2+}$. But, $Fe^{2+}$ did not reactivate the enzyme. Coexistence of 0.5 mM $Fe^{2+}$ and 0.5 mM $Mg^{2+}$ resulted in 95% reactivation of the enzyme, while $Fe^{3+}$ with 0.5 mM $Mg^{2+}$ did not reactivate the enzyme like the effect of $Fe^{2+}$ alone. The enzyme dialyzed against o-Phe showed the similar results. These data showed that $Fe^{3+}$ is predominantly required for the activity of the mitochondrial $F_1-ATPase$ in Lentinus edodes and stimulated the activity of it by $Mg^{2+}$. $Fe^{3+}$ and $Mg^{2+}$ increased enzyme's affinity for substrate, decreasing the Km value 1.67 mM to 0.65 mM.

• Childhood Kidney Diseases
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• v.12 no.2
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• pp.239-244
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• 2008

Calcification in patients with endstage renal disease on renal replacement therapy can occur in extraskeletal area such as conjunctiva and cornea. Conjunctival and corneal calcification(CCC) has mostly has been reported in adults with endstage renal disease on hemodialysis. CCC seems to be associated with the duration of renal replacement therapy, and high Ca$\times$P value. We report a 10-year-old girl who was on peritoneal dialysis for 31 months and presented with CCC on both eyes. Her corneal calcification was resolved after the epithelial debridement and ethylenediaminetetraacetic acid(EDTA) soaking therapy.

• Journal of the Korean Ceramic Society
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• v.55 no.6
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• pp.597-607
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• 2018

In this study, a wet chemical method was used to synthesize nanostructured hydroxyapatite for biomedical applications. Diammonium hydrogen phosphate and calcium nitrate 4-hydrate were used as starting materials with a sodium hydroxide solution as an agent for pH adjustment. Scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, differential thermal analysis, thermal gravimetric analysis, atomic absorption spectroscopy, and ethylenediaminetetraacetic acid (EDTA) titration analysis were used to characterize the synthesized powders. Having been uniaxially pressed, the powders formed a disk-like shape. The sinterability and electrical properties of the samples were examined, and the three-point bending test allowed for the measurement of their mechanical properties. Sedimentation analysis was used to analyze the slurry ability of hydroxyapatite. As in-vitro biological properties of the samples, biocompatibility and cytotoxicity were assessed using osteoblast-like cells and the L929 cell line, respectively. Solubility was assessed by employing a simulated body fluid.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.8
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• pp.1006-1013
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• 2011

An enzymatic treatment method using alcalase was introduced to improve the moisture characteristic of the polyamide fiber. The alcalase treatment conditions such as the pH, treatment temperature, enzyme concentration, and treatment time were optimized by measuring the amino groups. The changes in the weight loss, tensile strength, moisture regain, water contact angle (WCA), and water absorption rate of the polyamide fiber with the changes in the alcalase treatment conditions were evaluated. The optimum alcalase treatment conditions for polyamide fiber were found to be a treatment temperature of 50oC, a treatment time of 50 minutes, an alcalase concentration of 10% (owf), and a pH of 7.0. The ethylenediaminetetraacetic acid (EDTA) and L-cysteine accelerated the activity of the enzyme; however, they did not have an effect on the amino group production of the fiber surface. The alcalase treatment of the polyamide fiber improved the fiber's moisture regain, WCA, and absorption rate due to the amino group on the fiber surface. The results showed that the alcalase treatment of polyamide fiber is an effective method to improve the moisture characteristic of the polyamide fiber.

• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.213-219
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• 2014

Bacillus pumilus 2.g isolated from gembus, an Indonesian fermented soybean cake, secretes several proteases that have strong fibrinolytic activities. A fibrinolytic enzyme with an apparent molecular weight of 20 kDa was purified from the culture supernatant of B. pumilus 2.g by sequential application of ammonium sulfate precipitation, ion-exchange chromatography, and hydrophobic chromatography. The partially purified enzyme was stable between pH 5 and pH 9 and temperature of less than $60^{\circ}C$. Fibrinolytic activity was increased by 5 mM $MgCl_2$ and 5 mM $CaCl_2$ but inhibited by 1 mM phenylmethylsulfonyl fluoride (PMSF), 1 mM sodium dodecyl sulfate (SDS), and 1 mM ethylenediaminetetraacetic acid (EDTA). The partially purified enzyme quickly degraded the ${\alpha}$ and ${\beta}$ chains of fibrinogen but was unable to degrade the ${\gamma}$ chain.

• Journal of the Korean Chemical Society
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• v.17 no.2
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• pp.126-129
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• 1973

An amperometric method has been developed for the titration of silver with 2,5-dimercapto-1,3,4,-thiadiazole in ammonical solution (1N) using rotating platinum electrode as an indicator electrode and the mercury-mercury (II) iodide as reference electrode. Direct titration of milligram amount of silver (0.05-1.0mg) is possible in the presence of a number of foreign ions in ammonical solution containing ethylenediaminetetraacetic acid as masking agent under atmosphere. The interfering elements are gold and platinum. The milligram amount of silver can be determined by the proposed method within an error ${\pm}3{\%}$.