• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.79-86
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• 2019

The white aluminum phases in acid mine drainage usually precipitates when mixed with stream waters with relatively high pH. The minerals in white precipitates play important roles in controlling the behavior of heavy metals by adsorbing and coprecipitation. By the phase transition of these minerals in white precipitates, dissolution and readsorption of heavy metals may occur. This study was conducted to obtain preliminary information on the phase transition of the mineral phases in white precipitates. In this study, the mineral phase changes in the white precipitates collected from the stream around Dogye Mining Site over time were investigated with different pH values and temperatures. White precipitates consist mainly of basaluminite, amorphous $Al(OH)_3$ and a small amount of $Al_{13}$-tridecamer. During aging, the incongruent dissolution of the basaluminite occurs first, increasing the content of the amorphous $Al(OH)_3$. After that, pseudoboehmite is finally precipitated following the precursor phase of pseudoboehmite. At $80^{\circ}C$, this series of processes was clearly observed, but at relatively low temperatures, no noticeable changes were observed from the initial condition with coexisting basaluminite and amorphous $Al(OH)_3$. At high pH, the desorption of $SO{_4}^{2-}$ group in basaluminite was initiated to promote phase transition to the pseudoboehmite precursor. Over time, the solution pH decreases due to the dissolution and phase transition of the minerals, and even after the precipitation of pseudoboehmite, only the particle size slightly increased but no clear cystal form was observed.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.179-182
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• 2008

The KIDEA process, occurred in single reactor, is operated by three consequential steps, i.e., aerobic, settling, and discharge while introducing wastewater into the bottom of reactor continuously. It could accomplish biological oxidation (BOD), nitrification, denitrification (T-N), phosphate removal (T-P), and solid separation (SS) through the operational mode mentioned. Especially, this system has removed the T-P by wasting certain amount of sludge at the end of aeration phase during 5~10 minutes and not returned the activated sludge into the reactor, that is, no RAS (Return Activated Sludge). All running mode and instrumentation were controlled by the PLC equipment automatically. In this study, therefore, we have evaluated T-P removal efficiency and moisture content (MC) performance under the different excess sludge wasting mode. T-P track study and MC with TS concentration were analyzed during aerobic and settling phase. It has revealed that there was no significant difference of released T-P concentration between the first case which waste the sludge at the end of aerobic phase (0.2mg/L) and the second case which waste the sludge at 40 min of settling phase (0.25mg/L). Also, dewatering duration and MC have decreased 1.7% when TS concentration was increased from 0.31% to 0.5% during aerobic condition. Hence, it has concluded the system performance was less influenced by the operation time change of PLC program.

• Transactions on Electrical and Electronic Materials
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• v.13 no.6
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• pp.297-300
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• 2012

Lead-free (1-x)$(Na_{0.5}K_{0.5})NbO_3-xLiNbO_3$, i.e., NKN-LNx (x=0.0, 0.1, 0.2, 0.3, 0.4 mol) was prepared using the conventional solid state reaction method. The effects of LN mixing on the ferroelectric properties of NKN-LNx ceramics were studied using a dielectric constant and P-E (Polarization-electric field) measurements. Ferroelectricity was observed in the composition for x approximately varying between 0.0 and 0.4. Minimum remanent polarization $2P_r=5C/cm^2$ was achieved in the composition for x = 0.2. The ferroelectric phase transition temperature $T_C$ increased with increasing LN content. The ferroelectric phase transition of NKN-LNx ($x{\geq}0.1$) is a second-order phase transition, and that of NKN-LNx ($x{\leq}0.2$) is a first-order phase transition. These results indicate that the ferroelectric phase transition temperature of NKN-LNx change from that of second-order to weak first-order phase transition according to the LN content.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1150-1157
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• 2004

This experiment was conducted to investigate effects of phase feeding and sugar beet pulp (SBP) on growth performance, nutrient digestibility, nitrogen excretion, blood urea nitrogen (BUN) concentration and carcass characteristics in finishing pigs. A total of 128 pigs were allotted at 53.9 kg BW to 8 replicates in a 2$\times$2 factorial arrangement in a randomized complete block (RCB) design. The first factor was phase feeding (2 or 3 phase feeding) and SBP (SBP: 0% or 10%) was the second factor. Ten percent SBP supplement groups showed lower average daily feed intake (ADFI) than 0% SBP supplement groups (p<0.05). However, there were no significant difference in average daily gain (ADG) and feed:gain ratio among treatments during overall experimental period. Nutrient digestibility was not affected by phase feeding or SBP supplementation. Urinary nitrogen excretion in 10% SBP supplement group was lower than that in 0% SBP supplement group (p<0.05) and total nitrogen excretion was lower in SBP supplement group than in the group without SBP. Urinary and total nitrogen were numerically decreased in three phase feeding compared to two phase feeding. The BUN concentration in three phase feeding groups was lower than two phase feeding groups at 47 and 63 day (p<0.05). Consequently, results of this experiment demonstrated that three phase feeding was more acceptable than two phase feeding for finishing pigs. And sugar beet pulp could be supplemented in finishing pig diet for decreasing urinary nitrogen excretion without retardation in growth performance of pigs.

• Journal of Oral Medicine and Pain
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• v.26 no.1
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• pp.17-25
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• 2001

The purpose of this study is to evaluate the relationship of menstrual cycle and halitosis by measuring the concentrations of Voltile Sulfur Compounds, secretion rate of unstimulated saliva, secretion rate of stimulated saliva and viscosity of saliva during the menstrual cycle. The subjects were 19 female dental students of Yonsei University who had relatively good alignment of the teeth. They hadn't taken antibiotics or oral contraceptive pills during the few months prior to the experiment, and they didn't have any dental caries involving the pulp or periodontal disease. Lady-$Q^{(R)}$(Alpain Korea, Korea), which confirms the ovulation using saliva, was used to find out the menstrual cycle of subjects. Their history was taken and their basal body temperature was measured. On the basis of these data, the amount of Volatile Sulfur Compounds, secretion rate of unstimulated saliva, secretion rate of stimulated saliva, viscosity of saliva were measured during 1 day of the proliferative phase, 3 days of ovulatory phase and 1 day of the luteal phase within the menstrual cycle. The results were as follows : 1. The amount of Volatile Sulfur Compounds, secretion rate of unstimulated saliva, secretion rate of stimulated saliva, and viscosity of saliva showed no statistically significant cyclic change during proliferative phase, ovulatory phase, and luteal phase(p<0.05). 2. Between the secretion rate of unstimulated saliva and secretion rate of stimulated saliva, there was significant correlation during proliferative phase and luteal phase(p<0.05) and there was no significant correlation during ovulatory phase but relatively close result was seen. 3. The amount of Volatile Sulfur Compounds during proliferative phase and luteal phase had statistically significant correlation(p<0.05). 4. Secretion rate of stimulated saliva during proliferative phase and ovulatory phase, proliferative phase and luteal phase, ovulatory phase and luteal phase had significant correlations (p<0.01).

• KSBB Journal
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• v.16 no.1
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• pp.48-53
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• 2001

Bovine serum albumin(BSA) was solubilized into the reverse micellar phase consisting of sodium bis(2-ethylhexyl) sulfosuccinate(AOT) and isooctane using the phase transfer method. Of particular interest in this study were the effects of pH and the added salt type and concentration on the solubilization efficiency. When univalent or divalent salts such as KCl, NaCl, $MgCl_2$, or $CaCl_2$ were added to the aqueous phase at a concentration of 0.1 M, maximum solubilization efficiency was attained at a pH ranging from 5 to 7, depending on the added salt type. Increased salt concentration up to 1 M resulted in an increased solubilization efficiency for $CaCl_2$ and NaCl, while the addition of $MgCl_2$ beyond 0.1 M showed an anomalous trend. Further, it was noteworthy that too a large extent the protein precipitated in the interface between the organic and aqueous phases at lower pHs and lower salt concentrations. The size of the reverse micelle water pool was estimated by measuring the molar ratio of the surfactant to the water, $W_0$. Irrespective of pH in the aqueous phase, the resulting value of $W_0$ was almost constant, eg., 20 for $MgCl_2$ . However, the value of $W_0$ decreased with increased salt concentration in the cases of KCl and $CaCl_2$.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.965-973
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• 2021

The intention of this research is to analyze the effects of lactulose (LAC) supplementation on the growth performance, nutrient digestibility, microbial shedding, and fecal noxious gas emissions on weaning pigs in a 42-day trial. Based on the initial body weight and sex, a total of 255 piglets (21 day old) were randomly allocated into one of three dietary treatments with 15 replications and five pigs (two female and three male) per pen. The dietary treatments were as follows: a corn-soybean meal-based basal diet (CON) supplemented with 0, 1, and 2 g·kg^-1 of LAC. During phase 1, significant (p < 0.05) increases in the average daily feed intake and average daily gain (ADG) were observed, whereas during phase 2 and overall experimental period, significant improvements (p < 0.05) in the body weight, ADG, and gain to feed ratio were observed in pigs fed a graded level of LAC compared to those fed the CON diet. Additionally, dietary LAC supplementation significantly improved (p < 0.05) the nutrient digestibility dry matter, nitrogen, and gross energy in both phase 1 and phase 2. Moreover, the inclusion of LAC supplementation significantly increased (p < 0.05) the fecal Lactobacillus counts and reduced (p > 0.05) the E. coli counts in pigs. Furthermore, LAC supplementation reduced (p > 0.05) fecal ammonia and hydrogen sulfide gas emissions during phase 2. The results here indicate that the addition of lactulose at 1 g·kg^-1 and/or 2 g·kg^-1 would be optimal to improve the performance outcomes of weaning piglets.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.161-166
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• 2004

The effects of kimchis intake on Helicobacter pylori infection in the stomach, the counts of lactic acid bacteria in the large intestine, and bacterial enzymes ($\beta$-glucosidase, $\beta$-glucuronidase) and pH in feces were examined. A total of 20 participants (age range 34 ∼ 57) were assessed for H. pylori infection status by Be urea breath test. Fourteen participants were eliminated because they were H. pylori-negative. This study consisted of 4 consecutive phase, each of which lasted 4 weeks. Three hundred grams of kimchi were administered to H. pylori-infected subjects during the kimchi phase, followed by 4 weeks of control phase. During the control phase, subjects consumed 60 g of kimchi, the minimum amount in their customary diets. All participants were found to be H. pylori-positive during all experimental periods. During the kimchi phase, delta over baseline (DOB) level was lower than during the control phase, although significant difference between the kimchi and control phases were not found (p=0.9439). However, the counts of Lactobacillus sp. and Leuconostoc sp. significantly (p < 0.0005) increased during the kimchi phase. $\beta$-Glucosidase and $\beta$-glucuronidase activities and pH were significantly decreased by kimchi intake compared to control (p=0.000l). These results suggested that kimchi consumption did not show any therapeutic effect on H. pylori in the stomach. However, kimchi seemed to be a good food for colon health, since it increased the beneficial bacteria such as lactobacillus and decreased toxic enzyme ($\beta$-glucosidase and $\beta$-glucuronidase) activity and pH.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.140-145
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• 1987

The partition coefficient of the proteins of known effective hydrophobicity was determined in a poly (ethylene glycol)-dextran aqueous two-phase system. The changes in the partition coefficient was also determined when a fraction of PEG-palmitate (PEG-P) was added to the system. The partition coefficient of the proteins increased as the concentrations of PEG and dextran increased at a constant phase volume ration irrespective of the effective hydrophobicity of the proteins. When small amounts of PEG-P were added to the PEG phase, the partition coefficients of BSA and ${\beta}-lactoglobulin$, which had relative hydrophobicity (RI) of 700 and 120, respectively, increased more than ten-fold, whereas ovalbumin whose RI was 5 showed little change. The drastic increases m the partition coefficient were observed by the addition of PEG-P in 2% level to the PEG system. Addition of PEG-P over 5% level resulted in a slight further increase in the partition coefficient of all proteins tested.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.778-782
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• 2007

The Diphenyleneiodonium (DPI) is widely used as an inhibitor of flavoenzymes, particularly NADPH oxidase. In this study, we investigated the effect of DPI on the cell growth progression of human colon cancer cells HCT-116 (wild-type p53), HT-29 (p53 mutant) and human breast cancer cells MCF-7 (wild-type p53). DPI treatment in cancer cells evoked a dose- and time-dependent growth inhibition, and also induced the cell cycle arrest in C2/M phase. The peak of cell population arrested in C2/M phase was observed at12 hr after treatment of DPI. In addition, DPI significantly induced the expression of p53, which induces proapoptotic genes in response to DNA damage or irreparable cell cycle arrest, at 6 hr in DPI-stimulated cells. However, a catechol apocynin, which inhibits the assembly of NADPH oxidase, did not induce p53 expression. This suggest that p53 expression induced by DPI is not associated with the inhibition of NADPH oxidase. In conclusion, we suggest that DPI induces the expression of wild-type p53 by ROS-in-dependent mechanism in several cancer cells, and upregulated p53 may be involved in regulatory mechanisms for growth inhibition and cell cycle arrest at C2/M phase in DPI-stimulated cells.