• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1664-1672
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• 2013

Solar salt is manufactured naturally, and therefore, it contains insoluble substances such as sandy compounds. This study is performed in order to effectively produce clean sea salt by removing the impurities in sea salt through filtration and evaporation in a vacuum condition. Brine was concentrated and crystallized at $90^{\circ}C$ by a rotary vacuum evaporator, which was then recovered as salt crystals by filtration, and then the salt was dehydrated. Manufacturing yields were determined by the amount of water evaporation. Brine was concentrated to 40%, 50% and 60% of the initial volume of brine and manufactured salt were designated as 40S, 50S and 60S, respectively. The salt produced by this process is called ESBS (evaporated salt with brine from salt-farm). The yield of 40S, 50S and 60S were 7.22%, 10.79% and 15.06%, respectively. The NaCl concentration of 40S and 50S were 90.38% and 91.16%, respectively. From a sensory evaluation analysis, the most tasty salt was 40S and the bitter salt was 60S. The average contents of sand compound and insoluble substances in ESBS were 0.001~0.012% and 0.067~0.12%, respectively. The mineral compositions, such as Na, Mg, K, and Ca of 40S and 50S were similar with those of the natural solar salt. In solubility tests, the solubility (g of salt/100 mL $H_2O$/sec) of 40S, 50S, and 60S was 0.69, 0.70, and 0.69, respectively. On the other hand, the solubility of natural solar salt was 0.47. By comparing the water reabsorption rate analysis results, water reabsorption rate of 40S and 50S was about 3 to 5 times lower than that of the solar salt. In the aspects of physical and chemical properties, such as minerals, impurities, solubility and moisture re-absorption rate, salts developed in this study are judged to be better than that of the general solar salt.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.147-152
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• 2011

This study was conducted to examine whether efficiency of oocyte production from superovulated prepubertal goats. Fifteen prepubertal and twenty adult goats, maintained in a pen under natural day length and fed hay ad libitum, were pretreated with progestagen implanted CIDR for 10 days. Superovulation treatment of the goats received twice daily intramuscular injection of a total of 70 mg FSH for 3 days from Day 8 of CIDR. All the gonadotrophin treated goats were injected with 10 mg $PGF_2{\alpha}$ on Day 8 and 400~600 IU hCG in the afternoon on Day 10. Oocytes were recovered by follicle aspiration or oviduct flushing at 35 to 40 h after hCG injection through mid-ventral incision. The in vivo matured oocytes was activated by ionomycin (5 min) and 6-DMAP (3.5~4 h). The activated oocytes were cultured in mSOF medium containing 0.8% BSA at 38.5$^{\circ}C$ in an atmosphere of 5% CO$_2$, 5% O$_2$, 90% N$_2$ for 7~8 days. There was no significant difference in the mean number of CL and in vivo matured and follicular oocytes recovered. But, quality of I + II grade follicular oocytes was lower (p<0.05) in the prepubertal goat (25.0%) than the adults (52.4%). The same results were also observed in the cleavage and blastocyst rate of activated oocytcs. The cleavage and blastocyst rate from prepubertal derived oocytes were lower (p<0.05) in the prepubertal goat (54.5%, 23.3%) than the adult goat (86.8%, 46.6%). Considering overall these results, we suggest that maturation of donor goats is a major factor affecting recovered oocytes quality and in vitro development of activated goat oocytes.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.5
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• pp.543-553
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• 2010

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially $PM_{10}$ is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of $PM_{10}$ and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD). $PM_{10}$ samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using $PM_{10}$ mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, $Na^+$, $NH_4^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, and ${SO_4}^{2-}$) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. $PM_{10}$ for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average $PM_{10}$ concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1% to 43.8% since both platform and tunnel areas were completely blocked by screen doors. However, the contribution of the fine secondary aerosol source emitted from various outside combustion activities was increased from 14.8% to 29.9% presumably due to ill-managed ventilation system and confined platform space.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.340-345
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• 1993

In order to investigate the quality changes during the storage after curing were determined volatile basic nitrogen(VBN), amino nitrogen, total creatinine, total carotenoid, extents of browning, reducing sugar and glycogen. During the storage of $5{\pm}1^{\circ}C$ after fermented for 1 or 2 days at $25{\pm}1^{\circ}C$, amino nitrogen increased slowely. Whereas the total carotenoid and glycogen decreased. Browning did not occurred for 50 days. Total creatinine increased gradually until 20 days but reducing sugar increased continuously through 50 days of storage. The result of sensory evaluation during the storage of fermented ascidian added $0.1\%$ papain and protease-A with NaCl $10\%\;and\;15\%$ showed that original taste and flavor of ascidian for $30{\sim}40$ days of storage at $5{\pm}1^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.22-26
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• 1984

The effect of changes in body weight, some blood components and some inorganic ions in liver and kidney, were studied on male rats receiving ad libitum on 5, 40, and 200 ppm of mercuric chloride solution during so days. The results obtained were summarized as follows ; 1. The total body weights were decreased in proportion to increment of mercury concentration. The internal organs weights i. e. , liver, kidney, spleen, and heart, were generally increased. Especially, the weight increment of kidney was the highest by intaking of mercuric chloride solution. 2. There were no significant changes in hematocrit values, activities of GOT and GPT in blood of rats receiving mercuric chloride. On the other hand, the plasma levels of cholesterol were significantly increased. The receiving of 200 ppm mercuric chloride solution to rats was resulted in the remarkable reduction of total protein levels and A/G ratio in plasma. 3. The markable rise occured in the accumulation of Hg, in both liver and kidney in proportion to supplying in rats while there was a tendency decreasing of Cu, Zn contents in liver, whereas there was a tendency increasing of Cu, Zn in kidney of rats.

• Journal of Adhesion and Interface
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• v.18 no.2
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• pp.59-67
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• 2017

Recently, integration of parts is accelerating according to the growth of the smart mobile industry. The integration of these parts causes problems of interference phenomena between the parts, and the importance of electromagnetic wave shielding technology to solve this problem is highlighted. Electromagnetic wave shielding technology is implemented so as to reflect or absorb electromagnetic waves, and generally conductive materials are utilized for electromagnetic wave shielding. Transparent shielding technology is required according to recent industrial changes. In this research, we propose transparent the shielding film using imprint technology with conductive composite binder. Utilizing UV polymerized acrylic binder to produce a conductive composite binder. Spherical, plate and stacked silver particles were used for conductivity. The changes of the curing characteristics, conductivity and adhesion were observed according to the structural characteristics of the silver particles. The use of spherical particles was the most efficient in the curing process, and an additional curing system was required to complement the UV-shadowing structure. In the conductivity evaluation, the stacked structure showed excellent characteristics. The adhesion of spherical system was the best. It is evaluated as a result of irregularities on the surface. Ultimately, the patterned film using this showed excellent transparency characteristics.

• Korean Journal of Clinical Pharmacy
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• v.12 no.2
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• pp.91-95
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• 2002

The pharmacokinetics of intravenous paclitaxel (1 mg/kg) were investigated in rabbits with renal failure induced by folic acid. The area under the plasma concentration-time curve from time zero to time infinity (AUC) of paclitaxel was significantly (p<0.05) greater in rabbits with severe renal failure induced by folic acid $(1030\pm382)$ compared to that in rabbits with in moderate renal failure induced by folic acid $(780\pm209\;ng/ml{\cdot}hr)$. The apparent volume of distribution (Vd) $(0.008\pm0.002\;L/kg)$ and the elimination rate constant $(\beta)\;(0.09\pm0.025\;hr^{-1})$ of paclitaxel in rabbits with severe renal failure were significantly (p<0.05) smaller and slower respectively than those of control rabbits $(0.016\pm0.004\;L/kg,\;0.12\pm0.03\;hr^{-1})$, but not significantly different compared with that in rabbits with moderate renal failure $(0.010\pm0.003\;L/kg,\;0.10\pm0.026\;hr^{-1})$. total body clearance (CL) of paclitaxel in rabbits with severe renal failure $(0.97\pm0.183\;L/hr/kg)$ was significantly (p<0.05) slower than that in control rabbits $(1.68\pm0.440\;L/hr/kg)$, but not significantly different compared with that in rabbits with in moderate renal failure $(1.28\pm0.311\;L/hr/kg)$. The terminal half-life ($t_{1/2}$) of paclitaxel in rabbits with severe renal failure $(7.46\pm2.16\;hr)$ was significantly (p<0.05) longer than that in control rabbits $(5.75\pm1.44\;hr)$, but not significantly different compared to that in rabbits with moderate renal failure rabbits $(6.67\pm1.76\;hr)$. The above data could be at least partly decrease in due to paclitaxel excretion in rabbits with renal failure, since $7-15\%$ of interavenous paclitaxel was excreted via kidney as unchanged forms plus its metablites.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.201-212
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• 2002

The objective of this study was to investigate the treatment efficiency, kinetics, and morphological characteristics of biofilm in upflow $Biobead^{(R)}$ process, a kind of biological aerated filter(BAF). The $Biobead^{(R)}$ system showed high removal rates of $COD_{Mn}$(76~83%), $BOD_5$(67~88%) and SS(71~91%) for food wastewater with high salt concentration ($>4,000mg/{\ell}$) under short reaction times(2~3hrs). Even at aerobic condition, the system had high treatment efficiency for both T-N (51~63%) and T-P(62~81%). The removal kinetics of $COD_{Mn}$, $BOD_5$, T-N, T-P, and $Cl^-$ in the $Biobead^{(R)}$ system showed a plug-flow pattern with reaction rate constants($hr^{-1}$) of 0.58, 0.63, 0,30, 0.48, and 0.38 respectively. A backwashing process to remove excess biomass and filtered solids was needed at least once during 22-hour operation at $0.5kg\;BOD\;m^{-3}{\cdot}d^{-1}$ loading. At the higher loading($1.0kg\;BOD\;m^{-3}{\cdot}d^{-1}$) the backwashing interval was shorten by 8 hours. The COD, BOD, T-N, and T-P were removed from 43 to 66% only by aerobic biodegradation. The SS was removed over 70% by the filtering of $Biobead^{(R)}$ media in the treatment system. The first one of three serial Biobead reactors showed the highest removal values for $COD_{\alpha}$(52.3%), $COD_{Mn}$(38.8%), BOD(62.5%), and T-N(40.0%). The SS and T-P had the highest removal values(47.5% and 29.2%) at the second one of the serial reactors. The biofilm had non-homogeneous spatial distribution and the colonies were embedded in the sunk area of the Biobead. The thickness of the biofilm was very thin ($5.0{\sim}29.4{\mu}m$) compared to the biofilm thickness($200{\sim}300{\mu}m$) used in other BAF systems.

• 한국해양학회지
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• v.7 no.1
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• pp.24-45
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• 1972

The Han River is an important water source in Seoul and neighbouring districts, for public and industrial supply, and for agriculture and fishery. Nowadays, more than six million inhabitants are supplied withe water from this river. The total length of the river is 470km, and has 17 10$\^$9/㎥ an average annual flow. The hydrographic characteristics at Seoul are 653㎥/sec in an average flow, 4,608㎥/sec in the maximum average flow, and 201㎥/sec in the minimum average flow. These are influenced in some degree by snowmelt in early spring, and greatly by the flood during summer. For the pollution problems, the periods of low flow are critical ones. As a rule they occur around the months November through June. Nowadays, most of the sewage from towns and industries is discharged untreated. Apart from domestic and industrial sewages, there are some discharges of mineral matter by mines in the upriver region. In general, water quality of the Han River is kept very clean and healthy until Kwangnaru of the upper region of Seoul. A large pollution, however, is received in the downstream by the domestic and industrial sewages of Seoul. It can be seen that dissolved oxygen, COD and BOD$\sub$5/ diminish markedly, and the intensity of almost every water parameter of the river continues to increase. Comparison of the figures for 1971 derived from a sampling point 40km downstream of Kwangnaru leads to the conclusion that hardness, Ca and Mg were no changed; alkalinity, Si and soluble- Fe were slightly increased; CO$\sub$2/, acidity, Cl, NO$\sub$2/-N, Cu, Zn and Al were increased in 2 and 3 times; total residue, total ignitious residue, COD, BOD$\sub$5/, NH$\sub$4/-N, PO$\sub$4/-P, Mn, Pb and total-Fe were increased in 4 to 7 times; and SO$\sub$4/, particulate-Fe and Cd were increased in 10 to 11 times. On the other hand, coliforms were increased in 650 times; fecal coliforms in 365 times; enterococci and total plate counts in 30 times, respectively. In view points of water quality standards, the down Han River water is now leveling out in Cd, coliforms and fecal coliforms for the agricultural use; in dissolved oxygen and some trace elements (Cu, Zn, Pb and Cd) for the fishery use; in ammonia, COD, BOD$\sub$5/, and Cd for the drinking use.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.78-85
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• 1997

To determine the optimum coagulants concentrations for preparing soybean-curds, the transmittance of soybean-curd whey using spectrophotometer has been measured. The textural properties of soybean-curds were examined by texture analyzer and sensory evaluations. The general components, oligosaccharides and amino acids in soybean-curd wheys were analyzed. Protein patterns of soybean-curd wheys comparing with soyflour and soymilk were investigated. By texture analyzer, hardness, cohesiveness, springiness, and gumminess of Cacl$_2$ soybean-curd, MgCl$_2$ soybean-curd were higher than those of CaSO$_4$ soybean-curd and GDL soybean-curd. In the sensory evaluations, CaSO$_4$ soybean-curds and GDL soybean-curds were smoother and moister than others. Glutamic acid and aspartic acid were the first two abundant amino acids in three kinds of soybean-curd wheys, but arginine was the most abundant amino acid in GDL soybean-curd whey. Total sugar content of soybean-curd wheys were about 12-13 g/l, and the main sugars among 5 kinds of sugars were sucrose and raffinose. Electrophoresis using SDS-PAGE showed that glycinin and P-conglycinin, the main proteins of soybean appeared in soy flour and soymilk, and only low molecular weight subunits appeared in soybean-curd wheys.