• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.108-113
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• 1997

In this paper, the optimum condition of (110) Si etching with the potassium hydroxide(KOH) etchant is presented. Although several researches on (110) Si anisotropic etching have been studied, there has been lack of effects of mask quality and etching conditions on the selectivity and the roughness o the etched surface. Three kinds of masks (film, emulsion and E-beam mask) were used in order to verify the effect of etching properties. Anisotropic bulk etching depends on the crystalline orientation and the concentration and temperature of the etchant. In order to investigate the effect of etching conditions on selectivity and the roughness of the etched surface, the concentration of the etchant was varied from 35 to 45 per cent in weight with increments by 5 per cent and the temperature was changed from 70 to 90$^{\circ}C$ with increments by 10$^{\circ}C$. The combination of the temperature of 70$^{\circ}C$ and the concentration of 40wt.% was found to be the optimum etching condition for high selectivity. Etched surfaces show minimum surfaces show minimum surface roughness at a temperature of 80$^{\circ}C$ and a concentation of 40wt.%. Comb structures with various comb widths were fabricated and the lengths of the combs wree measured with several etching time durations. A micro comb structure 525$\mu\textrm{m}$ high was fabricated for MEMS application.

• Food Science and Industry
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• v.51 no.2
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• pp.127-135
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• 2018

The action of antioxidants was different depending on the environments where antioxidants were located. Although basic mechanisms of lipid oxidation and antioxidants were related each other, their contribution on the degree of oxidation was different. In thisreview, terminology on antioxidant properties were defined such as antioxidant activity and antioxidant capacities. In addition, antioxidant mechanisms including primary and secondary antioxidants or hydrogen donating or electron transferring antioxidants were introduced. Also, the impact of physical points of view and antioxidant polar paradox were introduced. Depending on the types of food matrice including bulk oil, oil-in-water emulsion (O/W), or solid state, antioxidant actions showed different degree and this point was explained in detail.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.67-70
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• 1994

On this study, we fabricated humudity sensor with polyimide thin film from the nonaqueous emulsion by the electrophoretic deposition as a function of film thickness. then evaluated performance of the sensor with increasing relative humidity if constant temperature constant humidity chamber, which is electronically controlled. we designed upper electrode of the sensor to brush type to make moisture particles permeate into the polymer bulk. sensing properties of the sensor on % RH shows proportion on the low %RH. Fer the 30V-30S- 200$^{\circ}C$ sample, percentage changing of capacitance on from 30 %RH to 90 %RH is 45.8 %, and increasing rate per 1 % RH of capacitance is 11.25 pF

• Explosives and Blasting
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• v.32 no.1
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• pp.23-30
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• 2014

The overall management for explosives in domestic and regulation for blasting is managed by the control Act of guns, sword, explosives etc. On the details for handling and method, delivery, storage, use and management for explosives and work safety for the accident prevention is recommended to the related business site through Standard safety work guideline of blasting which set by safety & health 27 Act handling. In this study, It reviews the standard safety work guideline of blasting notified by Ministry of employment & labor. We propose the new products introduced into domestic explosives market, definition of explosives word when the newest blasting technology is revised, emulsion explosives, bulk explosives and electronic detonators which increased in the latest. Indeed, We propose a typical handling method of non-electric detonator and electronic in order to make the renewed Standard safety work guideline of Blasting on work guideline.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1278-1286
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• 2008

The effect of Tween 20 addition on changes in the stability of methylcellulose (MC) emulsions (1 wt% MC, 10 wt% n-tetradecane, 20 mM bis-tris buffer, pH 7) was investigated by creaming stability and orthokinetic stability measurements. In the case of MC emulsions containing varying amounts of oil (1$\sim$30 wt%) and no Tween 20 added, creaming stability, judged by mean migration velocity of fat globules ($V_m$), was found to depend on droplet size: the larger the droplet size, the worse the stability [$V_m$: 0.326 $\mu$m $min^{-1}$ ($d_{32}$: 0.32 $\mu$m) ${\rightarrow}V_m$: 0.551 $\mu$m $min^{-1}$ ($d_{32}$: 0.53 $\mu$m)]. With Tween 20, creaming stability was found to be worse than the one without Tween 20, except for MC emulsion containing 0.2 wt% Tween 20. In addition, cream stability was the lowest with the lowest concentration of Tween 20 and a tendency to recover with increasing Tween 20 concentration [$V_m$: 0.598 $\mu$m $min^{-1}$ (0.01 wt%)${\rightarrow}V_m$: 0.389 $\mu$m $min^{-1}$ (0.2 wt%)] was found. From viscosity measurement for aqueous bulk phase of MC emulsions, such a change in the creaming stability was found to coincide well with the results of viscosity measurement. Therefore, it was reasonable to say that creaming stability of MC emulsions containing Tween 20 depended on MC concentration in aqueous bulk phase, which was in turn varied by competitive adsorption between MC and Tween 20 at the oil droplet surface. In case of orthokinetic stability, judged by destabilization time ($t_d$), it was found that the addition of Tween 20 resulted in lowered stability with more pronounce tendency at higher concentrations [$t_d$: 160 min (0.03 wt%)${\rightarrow}t_d$: 100 min (0.2 wt%)]. Moreover, combined with previous results, the orthokinetic stability of MC emulsions containing Tween 20 was found to be exponentially proportional to MC load. In conclusion, competitive adsorption between MC and Tween 20 may affect the stability properties of MC emulsion to varying extents, depending on the concentration of Tween 20.

• Membrane Journal
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• v.6 no.2
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• pp.86-95
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• 1996

Rotary disc ultrafiltration module(RDM) was developed for the separation of oil e$$\mu$sions. This module was devised to reduce the gel polarization phenomenon by decoupling the operation pressure and the surface velocity of solution in ultrafiltration(UF) processes. The rotary disc membrane consists of 3mm-thick ABS plate covered with UF membrane (UOP, U.S.A.). When the angular velocity($\omega$) was increased, the pure water flux was slightly decreased due to pressure drop caused by centrifugal force and slip flow at the surface of membrane. The pressure drop was proportional to the square of linear velocity(${\omega}r$). When the angular velocity was changed from 52.36rad/s to 2.62rad/s, the flux decline for 5% cutting oil in one-shaft RDM at $25^{\circ}C$ and 0.1MPa was 30.16%. In the lower concentrations, angular velocity tends to give less effect on the flux. Flux(J; $kg/m^{2} \cdot s$) in a rotating disc module is mainly a function of the bulk concentration($C_{B}$; %), the linear velocity(${\omega}r$; m/s) and the effective transmembrane pressure($\Delta P_{T}$ ; Pa). Using a modified resistance-in-series model, the flux data of cutting oil experiments were fitted to give the following equation.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.1-8
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• 1987

Eighty eight percent of succinylation at $\varepsilon$-amino group of lysine was obtained from silkworm larvae protein concentrate and it resulted in increased bulk density and fat absorption, improved flavor and color, increased solubility over fivefold. Both emulsifying activity and emulsion stability of the succinylated protein were improved by 30% and emulsifying capacity was enhanced by 4%. Foaming capacity of the succinylated Protein concentrate was improved by 30% and foaming stability improved fivefold. The viscosity of succinylated silkworm larvae protein concentrate was increased at all concentrations and reached the highest at 4~5% of concentations. Acetylation of silkworm larvae protein concentrate caused negligible change in the functional properties studied. Therefore, high emulsification properties of silkworm larvae protein concentrate would be a good protein source for the emulsified foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.410-422
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• 1989

Soybean protein isolates were acylated with succinic anhydride and partially hydrolyzed with trypsin. Chemical modification decreased protein contents of samples and, in amino acid composition, tyrosine was increased comparatively. And lysine was increased remarkably by partial proteolysis. Succinylation and trypsin treatment increased the aqueous solubility and shifted the isoelectric potint that showed high pH-dependence of protein solubility. Protein solubility was influenced by salt concentration such as $NaCl,\;CaCl_2,\;NaNO_3$ and $NaH_2PO_4$. Chemical modification increased the absorption of oil and water, emulsification properties and foam capacity, but decreased foam stability, ultraviolet absorbance and bulk density. Protein-protein Interaction between soybean protein isolates and beef protein increased the emulsifying activity, emulsifying activity index and foaming properties, but it didn't have any influence on emulsion stability.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.321-325
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• 1983

This study was carried out to investigate the nutritive value and functional proterties of chloroplastic protein and cytoplasmic protein which are a leaf protein concentrates of acacia. The results obtained are as follows; 1. The limited amino acids of chloroplastic protein and cytoplasmic protein in acacia leaf were methionine & tryptophan in both cases. 2. Digestibilities of chloroplastic protein and cytoplasmic protein were 72.59% and 60.24%, respectively. 3. Bulk density, water absorption, emulsifying capacity and emulsion stability of the chloroplastic protein and cytoplasmic protein were not greatly different from those of milk casein, but water solubilities of those were lower than that of milk casein. 4. Fat absorption of the cytoplasmic protein was similar to that of milk casein, but that of the chloroplastic protein was lower than that of milk casein.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.708-715
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• 1995

Effect of enzymatic modification with pepsin, papain and trypsin was studied on functional properties of isolated sesame meal protein hydrolysates. Solubility of protein hydrolysates distinctively increased from 2% to $53{\sim}94%$ at pH 4. Emulsifying properties showed marked increase 6 fold and 4.5 fold at degree of 10%, 20% hydrolysis by trypsin and degree of 10% hydrolysis by papain. The emulsion stability of the protein was unstable by heat treatment for 30 min. at $80^{\circ}C$. Foaming properties were also enhanced by enzymatic hydrolysis except at degree of 30% hydrolysis. Bulk density and water absorption of protein with trypsin and papain decreased about 0.1 g/ml and $0.3{\sim}0.7\;ml/g$, but oil absorption was increased about 1 ml/g.