• Journal of Environmental Science International
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• v.27 no.9
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• pp.743-751
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• 2018

The objective of this study was to investigate the adsorption potential of chicken feathers for the removal of OrangeII (AO7) from aqueous solutions. Batch experiments were performed as a function of different experimental parameters such as initial pH, reaction time, feather dose, initial OrangeII concentration and temperature. The highest OrangeII uptake was observed at pH 1.0. Most of the OrangeII was adsorbed at 2 h and an adsorption equilibrium was reached at 6 h. As the amount of chicken feather was increased, the removal efficiency of OrangeII increased up to 99%, but its uptake decreased. By increasing the initial concentration and temperature, OrangeII uptake was increased. The experimental adsorption isotherm exhibited a better fit with the Langmuir isotherm than with the Freundlich isotherm, and maximum adsorption capacity from the Langmuir constant was determined to be 0.179244 mmol/g at $30^{\circ}C$. The adsorption energy obtained from the Dubinin-Radushkevich model was 7.9 kJ/mol at $20^{\circ}C$ and $30^{\circ}C$ which indicates the predominance of physical adsorption. Thermodynamic parameters such as ${\Delta}G^0$, ${\Delta}H^0$, and ${\Delta}S^0$ were -12.28 kJ/mol, 20.64 kJ/mol and 112.32 J/mol K at $30^{\circ}C$, respectively. This indicates that the process of OrangeII adsorption by chicken feathers was spontaneous and endothermic. Our results suggest that as a low-cost biomaterials, chicken feather is an attractive candidate for OrangeII removal from aqueous solutions.

• Polymer(Korea)
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• v.32 no.1
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• pp.43-48
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• 2008

In this study, the hyper branched poly (styrene-co-divinylbenzene) (PSD) was synthesized by bulk polymerization and the cationic exchanger with high ion exchange capacity was prepared by sulfonation. The structure of hyper branched PSD ion exchanger was investigated by FT-IR, $^1H-NMR$ spectroscopy, and GPC analysis. The molecular weight, viscosity of hyper branched PSD increased with DVB content, which have the maximum values of 9410g/mol and 338 cP, respectively. And the reaction rate also increased with cross-linker content. As DVB content increased, the solubility of PSD decreased having the maximum value of 22 g with 0.1 mol% DVB. The water content and ion exchange capacity of the hyper branched PSD ion exchanger increased with the amount of sulfuric group. Their maximum values were 18.2% and 4.6 meq/g, respectively. The adsorption of copper and nickel ion was completed within 40 min.

• Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.108-113
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• 2002

Apical and subapical fragments of Gracilaria verrucosa (Hudson) Papenfuss (Rhodophyta) were cultured on a temperature-light gradient table with four temperature $(15,\;20,\;25\;and\;30^{\circ}C)$ and five light intensity $(20,\;40,\;60,\;80\; and\;100{\mu}mol\;photons\;m^{-2}s^{-l})$ regimes to examine growth responses. Their growth was measured weekly. Plant weight and lateral branch formation were affected by temperature and light intensity. As compared with other reports, relative growth rate (RGR) in both fragments was more or less high with 6.27 to $11.95\%$ $day^{-1}$. It was lowest at $15^{\circ}C$ with $20\mu mol$ photons $m^{-2}s^{-l}$, whereas, the highest value was recorded at $25^{\circ}C$ with $100\mu mol$ photons $m^{-2}s^{-l}$ During the experimental period, the growth pattern in G. verrucosa was significantly different between apical and subapical fragments, even though RGR based on weight was similar. Growth in apical fragments depended on elongation by apical growth. By contrast, subapical fragments mainly increased their weights by proliferation of lateral branch. This suggests that intercalary activity (e.g. lateral branch formation) is also an important means for growth of the thallus in Korean G. verrucosa. In conclusion, the relatively high growth potential with the intercalary activity in G. verrucosa will be helpful for mariculture in Korea.

• Neonatal Medicine
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• v.17 no.2
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• pp.250-253
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• 2010

Citrullinemia type I is an urea cycle defect caused by mutations in the argininosuccinate synthetase (ASS1) gene. We report a novel argininosuccinate synthetase gene mutation in a Korean family with type I citrullinemia. Metabolic evaluation revealed significant hyperammonemia. Amino acid/acylcarnitine screening using tandem mass spectrometry showed high level of citrulline. Plasma amino acid analysis showed high level of citrulline and the urine organic acid analysis showed makedly increased level of orotic acid. To confirm diagnosis of citrullinemia we did mutation analysis of the ASS1 gene. The patient was found to have mutations of c.689G>C (p.G230A) and c.892G>A (p.E298K), which were new types of argininosuccinate synthetase gene mutation have never been reported in Korea. We report a novel case of argininosuccinate synthetase 1 gene mutation and suggest that the gene study to the family members is necessary to carry out when a patient is diagnosed as citrullinemia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.720-726
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• 1995

Chemical components relevant to the characteristic taste of the Korean native persimmon(Diospyros kaki, Thumb) leaf tea were analyzed. Samples were processed by using three different methods ; SHT(steamed and then hot-air dried), DHT(dried in the shade, steamed and then hot-air dried) and RHT(roasted and then hot-air dried). The components analyzed were general compositions of dried perisimmon leaves and extracted solution. The composition of moisture, ash, crude lipid and total nitrogen did not show significant variation among different processing methods of the persimmonleaf tea. The contents of caffeine, tannin and vitamin C in persimmon leaf tea were in the range of $178.4~209.8{\mu}mol/g$, 29.1~38.5mg% and 325.3~2084.7mg%, respectively. The vitamin C content was significantly higher in the RHT than other treatments. The contents of caffeine, tannin and vitamin C in the tea extracted solution were in the range of $101.5~130.1{\mu}mol/g$, 15.4~25.9mg% and 111.0~1274.3mg%, respectively. The vitamine C in the tea solution was the highest in the RHT treatment and 61.1% of vitamin C in the leaf tea was extracted out in these processing methods. The major amino acids contained in the leaf tea were in decreasing order glutamic acid, aspartic acid, leucine and phenylalanine, these four amino acids consisting 38.9~39.8% of the total amino acid contained in the persimmon leaf tea. The major amino acids contained in the tea solution were glutamic acid, proline, histidine and arginine. Six kinds of 5'-nucleotides, CMP, AMP, UMP, IMP, GMP and hypoxanthine were detected and CMP was the most abundant component in fresh leaf, leaf tea and tea solution. The second highest 5'-nucleotides in both leaf tea and tea solutions were GMP, AMP and UMP in all processing method. The highest free sugar contained in the fresh leaf tea and tea solution was sucrose.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.463-466
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• 2001

In recent year, Ferroelectric BLT($Bi_{4-x}$La$_{x}$Ti$_3$O$_{12}$) is a promising candidate materials. This study was Practiced to make good conditions of BLT targets. In this study, calcination and sintering temperature were kept at 75$0^{\circ}C$, 110$0^{\circ}C$ for 2 hour respectively. the density obtained 7.612, 7.98, 7.877 g/㎤ as La$_2$O$_3$ contents were 0.0mol%, 0.25mo1%, 0.5mol%. Especially, the lanthanum content of 0.5 mol% measured C-axis (117) preferred orientation more than the others targets in the XRD. In $\varepsilon$$_{r}$-f relationship using by HP 4194 A impedance analyzer, the 0.5 mol% observed above 200 relative dielectric constant. but the dissipation factor was higher than others targets at 100Hz~13MHz range. SEM photograph with the content of La$_2$O$_3$ was observed like rod and plate types.types.s.

• Food Science and Preservation
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• v.15 no.3
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• pp.450-455
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• 2008

Previously, we have shown that green tea extract lowers the intestinal absorption of cholesterol, fat, and other fat-soluble compounds. We conducted this study to determine whether green tea extract affects the rate of $^{14}C$-oleic acid esterification into various lipids in the intestinal mucosa of rats. Male Sprague-Dawley ruts were had free access to a nutritionally adequate AIN-93G diet and deionized water. Initially, the rat's mucosal content of total lipids was measured following 1 mL olive oil administration with (green tea group) or without (control group) 100 mg green tea extract powder. At 1 h and 5 h, intestinal segments were extracted for total lipid analysis. Secondly, to measure mucosal esterification rates of lipids, an abdominal incision was made along the midline, and a 10-cm long jejunal segment of the small intestine was ligated in situ. Then, micellar solutions with or without green tea extract were injected into the ligated jejunal segments and incubated for 10 mill. The micellar solution contained $200.0\;{\mu}$ Ci $^{14}C$-oleic acid, $200.1\;{\mu}mol$ unlabelled oleic acid, $66.7\;{\mu}mol$ 2-monooleoylglycerol, $66.7\;{\mu}mol$ palmitoyl-sn-glycero-3-phosphocholine, 2.2 mmol glucose, $50.0\;{\mu}mol$ albumin, and 16.5 mmol Na-taurocholate per L of phosphate buffered saline (pH, 6.3) with or without 8.87 g green tea extract powder. At 10 min, each rat was sacrificed by cervical dislocation under anesthesia and the segment was removed for lipid analysis. Significant differences were observed in mucosal triglyceride content at 1 h and 5 h in ruts given green tea extract. Significant differences in the rate of $^{14}C$-oleic acid esterification into triglycerides and phospholipids fractions were observed between control and green tea groups. However, There were no significant differences in other lipid fractions. These results indicate that the lowered esterification rates of $^{14}C$-oleic acid into triglycerides and phospholipids fractions is attributable to presence of green tea extract. This may be associated with an inhibitory effect of green tea catechin on the mucosal processes of lipids, leading to the inhibition of intestinal absorption of lipids.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.6
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• pp.493-501
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• 2000

The microstructure and electrical properties of ZnO-Pr$_{6}$/O$_{11}$-CoO-Er$_{2}$/O$_{3}$ based varistors were investigated with Er$_{2}$/O$_{3}$ additive content of the range 0.0 to 2.0 mol%. Most of the added Er$_{2}$/O$_{3}$ were segregated at the nodal points and grain boundaries and it coexisted with Pr$_{6}$/O$_{11}$ in the bulk intergranular layer. The average grain size was decreased in the range of 7.44 to 5.62${\mu}{\textrm}{m}$ at 130$0^{\circ}C$ and 18.36 to 9.11 at 135$0^{\circ}C$ with increasing Er$_{2}$/O sub 3/ additive content. The density of ceramics was in the range 4.87 to 5.08 g/cm$^3$ at 130$0^{\circ}C$ and 5.35 to 5.62 g/cm$^3$at 135$0^{\circ}C$. At 130$0^{\circ}C$ the varistors without Er$_{2}$/O$_{3}$ exhibited 29.66 in the nonlinear exponent and 28.23 $\mu$A in the leakage current whereas the varistors with 0.5 mol% Er$_{2}$/O$_{3}$ exhibited a high nonlinearity which is 52.78 in thenonlinear exhibited and 9.75 $\mu$A in the leakage current. At 135$0^{\circ}C$ the varistors without Er$_{2}$/O$_{3}$ exhibited a very poor nonlinearity indicating 2.08 in the nonlinear exponent and 133.79 $\mu$A in the leakage current whereas the varistors with 1.0mol% Er$_{2}$/O$_{3}$ exhibited a relatively high nonlinearity which is 36.79 in the nonlinear exponent and 5.92 $\mu$A in the leakage current. Therefore Er$_{2}$/O$_{3}$ was additive which greatly improve the nonlinearity. It is believed that ZnO-0.5 mol% Pr$_{6}$/O$_{11}$-1.0 mol% CoO-0.5 mol% Er$_{2}$/O$_{3}$ based ceramicss will be usefully used as a basic composition to develop the advanced pr$_{6}$/O$_{11}$-based ZnO varistors.ristors.ristors.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.308-313
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• 2000

Hydrous titanium oxide particles with anatase phase were prepared from 0.05 mol TiCl4 solution using NH4HCO3 as precipitant by the droopping precipitant method. The sequential change of pH is completed by a sudden and steep increase in a pH value of the range of 6~7 to which the concentration of adsorbed OH- and H+ ions on TiO2 surface is equal. Rutile phase started precipitating with anatase phase as an increase of reaction temperature above 6$0^{\circ}C$ in aqueous 0.05mol TiCl4 solution and its specific surface area was found to decrease from 452 $m^2$/g($25^{\circ}C$) to 164$m^2$/g(8$0^{\circ}C$). Specific surface area decreased rapidly when anatase powders precipitated at 4$0^{\circ}C$ were heat-treated at temperature higher 40$0^{\circ}C$. FT-IR result confirmed that it was due to the decrease of OH species within hydrous titanium oxides. The loss of ethanol after illumination of the powder heated at $600^{\circ}C$ and $700^{\circ}C$ for 4 h was 66 and 68.8%, respectively.

• Journal of the Korean Wood Science and Technology
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• v.51 no.1
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• pp.38-48
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• 2023

Two important steps in utilizing technical kraft lignin (KL) from black liquor to synthesize lignin-phenol-formaldehyde (LPF) resin are its extraction via precipitation and fractionation. However, the effects of precipitation pH and acetone fractionation on the characteristics of hardwood KL have not been studied for LPF resins. Therefore, this paper reports the effects of the precipitation pH of black liquor and acetone fractionation on the characteristics of KL from mixed hardwood species for LPF resins. The precipitation was conducted at various pH levels from 3 to 9 of black liquor to obtain crude KL (C-KL), which was used in acetone fractionation to produce acetone-soluble KL (AS-KL) and acetone-insoluble KL (AI-KL). Precipitation at pH 3 and 9 produced the highest and lowest yields of C-KL, respectively. As expected, the C-KL infrared spectra were similar regardless of the precipitation pH levels. As the pH increased, the molecular weight of C-KL increased. However, the molecular weight of AS-KL and AI-KL after acetone fractionation increased to a maximum of 4,170 and 47,190 g/mol at pH 7, then decreased to 3,210 and 19,970 g/mol at pH 9, respectively. The smallest molecular weights of AS-KL and AI-KL were 3,210 and 15,480 g/mol and were found at pH 9 and 3, respectively. These results suggest that both AS-KL at pH 9 and AI-KL at pH 3 have good potential as starting lignins for synthesizing LPF resins that require cross-linking for polymerization.