• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.213-217
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• 2003

The effects of glucose concentration on the production of PHB by fed-batch culture of Ralstonia eutropha were investigated. In the range of glucose concentration of $2.5\;{\sim}\;40\;g/l$, it was found that the high glucose concentration was not favorable for the PHB formation after the phosphate limitation. It was further confirmed by the specific PHB synthesis rates and yields. The PHB concentration decreased much with the increase of glucose concentration. But if the glucose concentration was very low, e.g. 2.5 g/l, the cell growth and PHB synthesis also could be limited because of inadequate glucose supply. Itwould be better to maintain the glucose concentration at about 9.0 g/l to obtain high DCW, PHB concentration and productivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.15-20
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• 2002

Quality variation of plastic pouch packing of Changran-Jeotgal produced by improved process and conventional process were investigated during storage at 10, 20 and $30^{\circ}C$, respectively. The kind of plastic pouch used in this study were polyethylene/nylon/linear low density polyethylene (PE/Ny), polyethylene terephthalatefpolyethyleneflinear low density polyethylene (PET) and low density polyethylene (PE). In the higher storage temperature, the faster increase of$ CO_2$, concentration and volume of pouch packing in all kinds of pouch. However, the highest value of pH, L-value, volatile basic nitrogen (VBN) and viable cell counts were shown in PE, the next was PET and PE/Ny, Overall, Changran-Jeotgal produced by improved process showed a little change of physical and chemical characteristics than conventional process. From above results, relationship between quality parameters were predicted pH, L-value, VBN and sensory score were highly correlated, therefore, these parameters is expected to uses as shelf-life indicated elements in cease of plastic pouch packaging.

• Journal of the Korean Ceramic Society
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• v.51 no.3
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• pp.190-196
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• 2014

Flexible $TiO_2$ films were deposited as dielectric materials for high-energy-density capacitors on polyethylene terephthalate (PET) substrates using a roll-to-roll sputtering method. Both the growth behavior and electrical properties of the flexible $TiO_2$ films were dependent on the sputtering pressure and $O_2$/Ar gas ratio during the sputtering process. All $TiO_2$ films had an amorphous structure regardless of the sputtering conditions due to the low substrate temperature. Microstructural characteristics such as the surface morphology and roughness of the films degraded with an increase in the sputtering pressure and $O_2$ gas concentration. The $TiO_2$ films deposited at a low pressure showed better electrical properties than those of films deposited at a high pressure. The $TiO_2$ films prepared at 10 mTorr exhibited a dielectric constant of approximately 90 at 1 kHz and a leakage current density of $5{\sim}6{\times}10^{-7}A/cm^2$ at 3 MV/cm.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.5
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• pp.31-36
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• 2010

When corrugated board is folded at the severely low humidity condition, crack can occur along the scored (or creased) lines of linerboard. This phenomenon is called as score (or crease) crack. It is mainly resulted from the excessive concentration of stress on the outer layer of linerboard. To overcome score crack, many approaches including the installation of constant temperature and humidity system, displacement of low grade raw material by long and strong fibers, or application of water have been tried. We examined the effect of the weight fraction of top layer in two-ply sheet, freeness of top layer stock and wet pressing on strain and elastic modulus of sheet to prevent score crack. Lower freeness and higher press load increased the density and elastic modulus of sheet. Pressing load over the $50kgf/cm^2$, however, decreased the strain of sheet. The weight fraction of top layer had positive effect on strain as well as elastic modulus without increasing the density of sheet.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.233-233
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• 2010

Magnetic random access memory (MRAM), based on magnetic tunnel junction (MTJ) and CMOS, is a prominent candidate among prospective semiconductor memories because it can provide nonvolatility, fast access time, unlimited read/write endurance, low operating voltage and high storage density. The etching of MTJ stack with good properties is one of a key process for the realization of high density MRAM. In order to achieve high quality MTJ stack, the use of CoFeB and IrMn magnetic films as free layers was proposed. In this study, inductively coupled plasma reactive ion etching of CoFeB and IrMn thin films masked with Ti hard mask was investigated in a $Cl_2$/Ar gas mix. The etch rate of CoFeB and IrMn films were examined on varying $Cl_2$ gas concentration. As the $Cl_2$ gas increased, the etch rate monotonously decreased. The effective of etch parameters including coil rf power, dc-bais voltage, and gas pressure on the etch profile of CoFeB and IrMn thin film was explored, At high coil rf power, high dc-bais voltage, low gas pressure, the etching of CoFeB and IrMn displayed better etch profiles. Finally, the clean and vertical etch sidewall of CoFeB and IrMn free layers can be achieved by means of thin Ti hard mask in a $Cl_2$/Ar plasma at the optimized condition.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.241-248
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• 2005

This study is aimed at understanding the role of arsenic in Roxarsone in causing fatty livers in mule ducks. One hundred 10-week-old mule ducks were randomly divided into 5 groups. Ducks received 2 weeks of various treatments followed by 2 weeks of withdrawal. The treatments were non-treatment (control), 300 mg/kg Roxarsone inclusion for 2 weeks ($1^{st}$ and $2^{nd}$ week), Roxarsone inclusion for one week ($2^{nd}$ week only), restrict feeding, or Roxarsone analogue (3-nitro-4-hydroxyphenyl acid) inclusion. Results showed that feed intake and body weight in the Roxarsone groups and the restrict feeding group decreased significantly during the treatment period. However only the liver and heart weights were significantly decreased (p<0.05) in the restrict feeding group. Fatty acid synthetase (FAS) activity showed a significant decrease (p<0.05) in the Roxarsone groups and the restrict feeding group, two-week-Roxarsone treatment significantly increased NADP-malic dehydrogenase (MDH) activity compared to the restrict (p<0.05). After 2 weeks drug withdrawal, the 1-week-Roxarsone or restrict feeding group showed significantly increased (p<0.05) glucose-6-phosphate dehydrogenase (G-6-PDH) activity (p<0.05). Two-week-Roxarsone treatment significantly decreased (p<0.05) the high density lipoprotein (HDL) and increased (p<0.05) the low density lipoprotein (LDL) and very low density lipoprotein (VLDL) ratio. After drug withdrawal, the 1-week-Roxarsone or restrict feeding group showed significantly increased (p<0.05) creatine kinase (CK) activity. The 2-week-Roxarsone treatment group showed significantly increased (p<0.05) aspartate aminotransferase (AST) activity. The restrict feeding treatment group showed significantly decreased (p<0.05) total protein (TP) concentration. After drug withdrawal, the related enzyme activities in the blood that reflected the liver function were restored to the normal physiological range, except for the total bilirubin concentration and CK activity in the 1-week-Roxarsone group. This group showed a significant increase (p<0.05). Thus, the reasons for liver enlargement in the Roxarsone and restrict feeding groups were different.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.299-308
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• 2019

The occurrence patterns of Acartia(Copepoda; Calanoida) species, A. erythraea, A. hongi, A. hudsonica, A. ohtsukai, and A. sinjiensis, were examined in the southern coastal waters of Korea in the summer in August 2012. The Acartia species had different spatial distribution according to environmental factors. A. erythraea showed higher density in a semi-closed bay (Gamak, Masan) where the dissolved oxygen was low (<2 mg L^-1). A. sinjiensis showed a high density in a semi-closed bay when the chlorophyll-a concentration was >2 ㎍ L^-1. A. ohtsukai showed a high density at water temperatures >26℃ and low salinity <30. A. hongi and A. hudsonica showed at water temperatures <27℃ and high dissolved oxygen (>5 mg L^-1). These results suggest that environmental factors (temperature, salinity, dissolved oxygen, and chlorophyll-a concentration) may affect the spatial distribution of Acartia species dominant in the southern coasts of Korea in summer.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.1
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• pp.23-33
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• 2011

Objectives : The present study investigated effects of Artemisia Capillaris Thunberg ethanol extract(EtOH ext). on lowering lipid, anti-oxidation and concentration of plasma inflammatory mediators using rat fed on high oxidized fat. Methods : We divided fat sprague-dawley rats fed on high oxidized into 4 groups. They were normal group, feed with 100 mg/kg Artemisia Capillaris Thunberg group, feed with 200 mg/kg Artemisia Capillaris Thunberg group and feed with 300 mg/kg Artemisia capilaris Thunberg group. They were administered for 4 weeks. We measured concentration of plasma free fatty acid(FFA), plasma triglyceride, plasma total cholesterol, and plasma low density lipoprotein-cholesterol(LDL-cholesterol), plasma high density lipoprotein-cholesterol(HDL-cholesterol), concentration of liver total cholesterol and liver triglyceride (TG), concentration of plasma thiobarbituric acid reactive substance(TBARS) and liver thiobarbituric acid reactive substance(TBARS), glutathione peroxidase (GSH-Px) activity, superoxide dismutase(SOD) activity and catalase(CAT) activity, plasma nitric oxide(NO), ceruloplasmin and ${\alpha}-glycoprotein$. Results : 1. The Artemisia Capillaris Thunberg EtOH ext. groups showed low concentration of plasma FFA, plasma triglyceride, plasma total cholesterol and plasma LDL-cholesterol compared to control group. However, concentration of plasma HDL-cholesterol was increased in the Artemisia Capillaris Thunberg EtOH ext. groups. 2. Concentration of liver total cholesterol and liver TG showed a significantly decrement in all Artemisia Capillaris Thunberg EtOH ext. groups than that of control group. 3. The Artemisia Capillaris Thunberg EtOH ext. groups showed lower values in concentration of plasma TBARS and liver TBARS than that of control group. The values of GSH-Px activity, SOD activity and CAT activity were increased in the Artemisia Capillaris Thunberg EtOH ext. groups. 4. The values of plasma NO, ceruloplasmin and ${\alpha}-glycoprotein$ were decreased in Artemisia Capillaris Thunberg EtOH ext. groups. Conclusions : Based on the results in this study, the Artemisia Capillaris Thunberg EtOH ext. showed a positive effect in lowering lipid, anti-oxidation and decrement of plasma inflammatory mediators.

• Corrosion Science and Technology
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• v.14 no.4
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• pp.177-183
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• 2015

Prestressed Concrete steel Cylinder Pipe (PCCP) is extensively used as seawater pipes for cooling in nuclear power plants. The internal surface of PCCP is exposed to seawater, while the external surface is in direct contact with underground soil. Therefore, materials and strategies that would reduce the corrosion of its cylindrical steel body and external steel wiring need to be employed. To prevent against the failure of PCCP, operators provided a cathodic protection to the pre-stressing wires. The efficiency of cathodic protection is governed by the anodic performance of the system. A mixed metal oxide (MMO) electrode was developed to meet criteria of low over potential and high corrosion resistance. Increasing coating cycles improved the performance of the anode, but cycling should be minimized due to high materials cost. In this work, the effects of $RuCl_3$ concentration on the electrochemical properties and lifespan of MMO anode were evaluated. With increasing concentration of $RuCl_3$, the oxygen evolution potential lowered and polarization resistance were also reduced but demonstrated an increase in passive current density and oxygen evolution current density. To improve the electrochemical properties of the MMO anode, $RuCl_3$ concentration was increased. As a result, the number of required coating cycles were reduced substantially and the MMO anode achieved an excellent lifespan of over 80 years. Thus, we concluded that the relationship between $RuCl_3$ concentration and coating cycles can be summarized as follows: No. of coating cycle = 0.48*[$RuCl_3$ concentration, $M]^{-0.97}$.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.2
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• pp.93-99
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• 2002

Effects of oxidized low-density lipoprotein (ox-LDL), $1-{\alpha}-stearoyl-lysophosphatidylcholine$ (LPC), on intracellular $Ca^{2+}$ concentration were examined in mouse endothelial cells by measuring intracellular $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ with fura 2-AM and reverse transcription-polymerase chain reaction (RT-PCR). LPC increased $[Ca^{2+}]_i$ under the condition of 1.5 mM $[Ca^{2+}]_o$ but did not show any effect under the nominally $Ca^{2+}-free$ condition. Even after the store depletion with $30{\mu}M$ 2,5-di-tert- butylhydroquinone (BHQ) or $30{\mu}M$ ATP, LPC could still increase the $[Ca^{2+}]_i$ under the condition of 1.5 mM $[Ca^{2+}]_o.$ The time required to increase [$Ca{2+}$]i (about 1 minute) was longer than that for ATP-induced $[Ca^{2+}]_i$ increase $(10{\sim}30\;seconds).$ LPC-induced $[Ca^{2+}]_i$ increase was completely blocked by $1{\mu}M\;La^{3+}.$ Transient receptor potential channel(trpc) 4 mRNA was detected with RT-PCR. From these results, we suggest that LPC increased $[Ca^{2+}]_i$ via the increase of $Ca^{2+}$ influx through the $Ca^{2+}$ routes which exist in the plasma membrane.