• Journal of the Korean Electrochemical Society
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• v.3 no.2
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• pp.115-120
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• 2000

All solid-state thin film micro-batteries consisting of lithium metal anode, an amorphous LiPON electrolyte and cathode of vanadium oxide have been fabricated and characterized, which were fabricated with cell structure of $Li/LiPON/V_2O_5Pt$. The effect of various oxygen partial pressure on the electrochemical properties of vanadium oxide thin films formed by d.c. reactive sputtering deposition were investigated. The vanadium oxide thin film with deposition condition of $20\%\;O_2/Ar$ ratio showed good cycling behavior. In in-siか process, the LiPON electrolyte was deposited on the $V_2O_5$ films without breaking vacuum by r.f. magnetron sputtering at room temperature. After deposition of the amorphous LiPON, the Li metal films were grown by a thermal evaporator in a dry room. The charge-discharge cycle measurements as a function of current density and voltage variation revealed that the $Li/LiPON/V_2O_5$ thin film had excellent rechargeable properly when current density was $7{\mu}A/cm^2$. and cut-off voltage was between 3.6 and 2.7V In practical experiment, a stopwatch ran on this $Li/LiPON/V_2O_5$ thin film micro-battery. This result means that thin film micro-battery fabricated by in-siか process is a promising for power source for electronic devices.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.104-110
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• 2015

We analyzed the effects of various LED light treatments (red 655 nm, blue 456 nm, white and mixed light) on growth pattern, gene expression and flavonoid contents in lettuce leaf. Plants treated with mixed light (red+blue+white) showed better growth performance than those treated with single LED and fluorescent lamp (FL). Expression analysis of the eight genes involved in flavonoid biosynthesis in plants treated with LED light was examined. Results showed that red lettuce grown under mixed light showed high expression levels of LsC4H, LsF3H and LsDRF genes. Morever, the same treatment plants possessed higher content of gallic acid, chlorogenic acid and quercetin contents than those in plants exposed to single light. However, the highest total anthocyanin content was identified in plants treated with red+blue light and the lowest content was identified in plants exposed to white fluorescent lamp and single LED light condition. Thus, this study indicates that the ratio of blue to red LEDs is important for the morphology, growth, and phenolic compounds with anthocyanin properties in the two lettuce cultivars tested.

• Progress in Superconductivity
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• v.5 no.1
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• pp.50-54
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• 2003

We have fabricated $∂^2$$B_{z}$ /$∂x^2$ type planar gradiometers and studied their properties in operation under various field conditions. $YBa_2$$Cu_3$$O_{7}$ film was deposited on $SrTiO_3$ (100) substrate by a pulsed laser deposition (PLD) system and patterned into a device by the photolithography with ion milling technique. The device consists of 3 pickup loops designed symmetrically Inner dimension and the width of the square side loops are 3.6 mm and 1.2 mm, respectively, and the corresponding dimensions of the center loop are 2.0 mm and 1.13 mm. The length of baseline gradiometer is 5.8 mm. Step-edge junction width is 3.0 $\mu\textrm{m}$ and the hole size of the SQUID loop is 3 $\mu\textrm{m}$ ${\times}$ 52 $\mu\textrm{m}$. The SQUID inductance is estimated to be 35 pH. The device was formed on a 20 mm ${\times}$ 10 mm substrate. We have tested the behavior of the device in various field conditions. The unshielded gradiometer was stable under extremely hostile conditions on a laboratory bench. Noise level 0.45 pT/$\textrm{cm}^2$/(equation omitted)Hz and 0.84 pT/$\textrm{cm}^2$/(equation omitted)Hz at 1 Hz for the shielded and the unshielded cases, which correspond to equivalent field noises of 150 fT/(equation omitted)Hz and 280 fT/(equation omitted)Hz, respectively. In spite of the short baseline of 5.8 mm, the high common-mode-rejection-ratio of the gradiometer, $10^3$, allowed us to successfully record magnetocardiogram of a human subject, which demonstrates the feasibility of the design in biomagnetic studies.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.707-717
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• 2018

Leukocytes are reportedly the first line of the innate immune defense and essential for the control of common bacterial infections. Therefore, in this work, the antibacterial activity of crocodile leukocyte extract against Propionibacterium acnes was evaluated, and we also characterized the related activity of skin infection. The leukocyte extract showed the minimum inhibitory concentration to be $100{\mu}g/ml$ to P. acnes. SEM imaging demonstrated that the leukocyte extract adversely affected P. acnes cell permeability in a concentration-dependent manner. Furthermore, the crocodile leukocyte extract could significantly reduce proinflammatory markers and decrease inflammatory signs in infected mouse ears. The crude leukocyte extract was further purified using FPLC and RP-HPLC. The resulting fraction F5 was indicated as the anti-acne peptide-containing fraction. The molecular mass of the peptide contained in F5 was calculated to be 4,790.5 Da. N-Terminal sequencing revealed the amino acid sequence as GPEPVPAIYQ, which displays similarities to immunoglobulin A and leucine-rich repeat neuronal protein. This is the first reported amino acid sequence of a crocodile leukocyte extract that possesses anti-acne activity. To attempt to use it in a prototype cosmetic, an anti-acne gel containing crude crocodile leukocyte extract was formulated, resulting in seven gel formulations (G1, G2, G3, G4, G5, G6, and G7). The formulations G5, G6, and G7 exhibited 2-fold higher anti-acne activity than G1-G4. Investigation of accelerating stability studies of anti-acne gel formulations G5, G6, and G7 demonstrated that a low storage temperature ($4^{\circ}C$) is suitable for maintaining the physical properties and biological activity of the anti-acne gel products.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.307-313
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• 2006

In order to improve the efficiency of methane steam reforming process, a part of the system which produces hydrogen from heavy hydrocarbon resources such as coal, we combined metal catalyst with CaO sorbent and fabricated catalyst/sorbent. To increase the porosity and the compressive strength of sorbent, carbon black and ${\alpha}-alumina$ were mixed with CaO powder during preparation. The effects of sorbent composition on the physical properties were investigated by SEM, TGA, BET, XRD, abrasion strength measuring device and adsorption-desorption instrument. Sorbent with 5 wt％ $Al_2O_3$ and 10 wt％ carbon black showed the best physical features with $7.61kg_f$ strength and 47％ $CO_2$ adsorption capability. Various metal catalysts such as Ni, Co and Fe were supported on the sorbent developed and 10 wt％ Ni/sorbent was selected for methane steam reforming process based on the result of reaction experiment. The reaction system using the catalyst/sorbent showed better $H_2$ productivity compared to the detached system with catalyst and sorbent, indicating the effectiveness of the system developed in this study.

• Journal of the Korean Vacuum Society
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• v.15 no.3
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• pp.287-293
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• 2006

Diamond-like carbon (DLC) film was deposited using benzene $(C_6H_6)$ by r. f-plasma assisted chemical vapor deposition. The tribological properties of the DLC film were tested by rotating ball-on-disc type tribometer isolated by a chamber. The tribological test was performed in air environment of relative humidity ranging from 0 to 90% in order to observe the tribological behavior of the DLC film with the change of humidity. We used steel ball and DLC coated steel ball to investigate the effect of the counterface material. Using steel ball, the friction coefficient of DLC film increased from 0.025 to 0.2 as the humidity increased from 0% to 90%. In case of DLC coated steel ball which didn't form the Fe-rich debris, the friction coefficient showed much lower dependence of humidity as 0.08 in relative humidity 90%. We confirmed that the high humidity dependence of the friction coefficient using steel ball resulted from the increase of debris size with humidity and the formation of Fe-rich debris by the wear of steel ball. And the friction coefficient was immediately dropped when the relative humidity changed from 90% to 0% during test using steel ball. From this result, we confirmed that the effect of the Fe-rich debris on the friction coefficient was that Fe element in debris formed the highly sensitive graphitic transfer layer to humidity.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.220-227
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• 2012

The objective of this study was to investigate the influence of emulsion processing with various homogenization treatments on the physical properties of nanoparticles. For the manufacturing of nanoparticles, by taking the emulsion-diffusion method, various coating materials, such as gum arabic, hydroxyethyl starch, polycarprolactone, paraffin wax, ${\kappa}$-carrageenan and emulsifiers like Tween$^{(R)}$60, Tween$^{(R)}$80, monoglyceride and Pluronic$^{(R)}$F68, were added into the emulsion system. Furthermore, the various speeds (7,000 rpm to 10,000 rpm), and times (15 s to 60 s) of homogenization were treated during the emulsion- diffusion process. NEO II homomixer was the most effective homogenizer for making nanoparticles as 51 nm ($D_{10}$) and 26 nm ($D_{50}$). To manufacture smaller nanoparticles, by using NEO II homomixer, 10,000 rpm of agitation speed, polycaprolactone as coating material, and Pluronic$^{(R)}$F68 as an emulsifier were the optimum operating conditions and components. For the stability of nanoparticles for 7 days, $20^{\circ}C$ of storage temperature was appropriate to maintain the particle size. From these results, the type of homogenizer, homogenization speed, homogenization time and storage temperature could affect the particle size. Moreover, type of coating materials and emulsifier also influenced the size and stability of the nanoparticles.

• Korean Journal of Materials Research
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• v.12 no.9
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• pp.706-711
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• 2002

High-pure tantalum powder was fabricated through Na reduction process and has been produced by using $K_2$TaF$_{7}$, and KCI, KF for raw material and diluent, respectively. A raw material and diluent were charged at the hestalloy bomb by the weight rate of 1:2, 1:1, 1:0.5 and 1:0.25 each other, investigated properties of morphology, chemical composition and yield and particle size after reduced. Ta metal has been achieved by reduction of $K_2$$TaF_{7}$ 500g with 1% sodium in excess of stoichiometric amount in the charge at a reduction temperature of $850^{\circ}C$ for 3hours. According to amount of the diluent, a formation of the powder doesn't have an effect. The diluent prevented the temperature rising caused from the heat of reaction and it maintained the speed of reducing reaction. But in the mixture ratio of raw material and diluent in the 1 : 2 and 1 : 0.25, an oxide and partially not reacted K were detected. As the amount of diluent increased, the size of tantalum powder decreased. According as raw material and the mixture ratio of diluent change from 1:0.25 to 1:2, the size is decreased from 5$\mu\textrm{m}$ to 1$\mu\textrm{m}$, and a particle size distribution which is below 325 mesh in fined powder increases from 71% to 83%. In the case of average size of Tantalum powder which is the mixture ratio (1:0.5), we would get the Ta powder with grain size about 3$\mu\textrm{m}$, which come close to the average size (2~4$\mu\textrm{m}$) of tantalum powder which is used commonly in the present is Ta powder about 3$\mu\textrm{m}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.477-484
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• 2008

For the effective use of the conger eel by-products, such as head and frame, Tang, which is the Korean-type soup, from conger eel by-products (TCEB) was developed and its food component characterization was compared with that of commercial Chueotang, loach Tang. According to the results of viable cells and coliform group of TCEB heated at $115^{\circ}C$ for various times, the reasonable $F_0$ value was 8 min. The proximate composition of TCEB was 90.7% for the moisture, 4.8% for the protein, 2.6% for the lipid, and 1.5% for the ash. The extractive-nitrogen content of TCEB was 243.1 mg/100 g, which was higher than that of commercial Chueotang, 208.0 mg/100 g. The total amino acid content of TCEB was 4,310 mg/100 g and its major amino acids were glutamic acid (637.3 mg/100 g, 14.8%), glycine (409.1 mg/100 g, 9.5%) and alanine (404.4 mg/100 g, 9.3%). TCEB was not felt in the sensual fish odor and its sensual taste was good. The health functional properties for health of TCEB were 1.29 as a PF (protection factor) for antioxidative activity and 39.4% for angiotensin Ⅰ converting enzyme (ACE) inhibiting activity.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.267-274
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• 2017

This study discusses the applicability of environmental friendly EVA based butyl rubber self-adhesive waterproof sheet designed to prevent corrosion of large scale pipes used in the water treatment facilities during th water treatment process. The experiments conducted tested the waterproofing sheet's adhesion strength on the steel surface of the pipes and checked for whether the material has the proper response properties against the various environmental conditions. In addition, it the sheet adhered to the steel pipe was to see if the adhesion hold against the water pressure due to the ingress of inflow water. Finally, the waterproofing sheet's adhesion strength was tested on a rusted steel surface to confirm whether the material has the necessary properties to secure stable adhesion strength and prevent corrosion of steel pipes at the same time during the process of installation or maintenance. As a result, the self-adhesive waterproof sheets showed that all attachments in the untreated, long term pressuring, immersion in chemical substance (hydrochloric acid, hypochlorous acid, sodium hydroxide), low temperature ($-20^{\circ}C$) conditions showed a adhesion performance of higher than 1.5N/mm, which is the performance standard of KS F 4934. Also, in the testing to check for the adhesion property against inverse water pressure, it was observed that the adhesion failure did not occur even up to $3.0N/mm^2$ pressure. Also, in the process of assessing the adhesion performance on rusted steel surface, specimens after 12 hours of corrosion treatment was shown to have 2.1N/mm, and specimens after 168 hours of corrosion treatment was shown to have 2.0N/mm adhesion strength performance.