• KSBB Journal
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• v.4 no.3
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• pp.266-270
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• 1989

Insect cell cultures were performed in laboratory-scale vessels. The batch growth of insect cells was affected by such parameters as serum content, other nutrients, seeding density, and mechanical agitation. Lactate and ammonium were not likely to be environmental factors that inhibited cell growth at the concentrations observed at the end of batch cultures. In addition, redox potential was found to be a useful index in monitoring low-level dissolved oxygen during the cultivation of insect cells. Recombinant protein production by cells infected with a genetically-modified baculovirus was also demons treated. The maximum beta-galactosidase synthesis of 2800 units per reactor volume was achieved at the dilution rate of $0.006hr^{-1}$.

• Journal of the Korean institute of surface engineering
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• v.1 no.1
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• pp.14.1-18
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• 1967

The characteristics of sulfuric acid anodized layer was studied under various Conbitions, acid concentration : 5-20%, temperature : 5-25$^{\circ}C$, bath voltate : 16 volts , bath agitain : mech agitation : mechanical . The Al+++ ion increase in anodizing baty, the film thickness under microscope, the comparative porosity and the thickness were determined. It was found that film thickness and the porosithy which are the main factors of determining andoized layet quality, rule the corrosing and abrasiion tesistance of the film, and that the porosity is increasing in the outerlayer. The formation mechanism was assumed as follows : The film thickness -increase is due to OH_ ion diffusion into compact non-conductive layer and Al+ + OH_ \longrightarrowAl(OH), Al(OH)+ + OH_ \longrightarrowAl(OH)+$_2$ , Al(OH)+$_2$ + OH_ \longrightarrowAl(OH)$_3$., the strong adhesion force is alse due to Al(OH) or Al(OH)$_2$ in transtion layer. And the pore-nucleation is produced by volume change between Al and Al$_2$O$_3$ and activated H$_2$O gas created by large reaction heat of Al+(x) +OH_ \longrightarrowAl(OH)x.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.327-333
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• 2015

This paper aims to manufacture nonwoven fabrics by wet-laid technology using Vectran$^{(R)}$ one of the highly favoured high-performace fiber. In previous study, a novel evaluation on fiber dispersion was studied to select optimum surfactant by the need for the control of fiber dispersion in water with reference to wet-laid nonwoven technology. 3 Types of sulfonate anionic surfactants were chosen and added in a stage of agitation to improve dispersion behavior of fibers in water. It was observed that the state of fiber dispersion in water affected various properties of nonwovens, including appearance, physical properties, and mechanical properties. Nonwoven added SDBS was uniform in web structure, thickness and weight. Its average pore was small in size and consisted of fine pores and the value of porosity was high. Further, the difference of tensile value between 2 directions was the least. Consequentially, as the dispersion behavior of fiber increases, nonwoven shows more balanced and uniform physical properties in all directions.

• Journal of the Korean institute of surface engineering
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• v.26 no.6
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• pp.291-298
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• 1993

In order to substitute for porous nickel anode in Molten Carbonate Fuel Cell(MCFC), porous cermet elec-trode was fabricated with Ni and Ni-P coated ceramic powder. Ni and Ni-P were coated by electroless plat-ing method in the nickel solution containing of hydrazine and sodium hypophosphate as a reducing agent. The plating solution was stirred by air and mechanical agitator. Ultrasonic irradiation was applied to the plating bath to improved the effect of agitation and coating speed. Electorde was formed by pressing method and doc-tor blade method followed by sinterd at$ 800^{\circ}C$ for 6 hours in H2 environment. Anode performance test carried out by potentiodynamic polarization technique in the MCFC operating condition and 154-161mA/$\textrm{cm}^2$ as ob-tained as a anode current density at the+100mV overpotential.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.7
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• pp.516-522
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• 2011

The largest problem of domestic anaerobic digestion is low digestion efficiency. Reasons of the problem would be low organic matters input, low mixing efficiency in digestion tank, refractory excess sludge etc.. In this study, screw attached disk-type concentration system and a mechanical mixing system, solubilization facility improvements were performed to solve problems. Through these improvements, the sludge conc. of the concentrator increased 2.6-fold and the volume reduction efficiency was increased 3.0-fold. In addition, the dead-space is reduced by mechanical agitation. Anaerobic digester gas production in the digestion tank is increased from $193.8m^3$ to $386.0m^3$ per day. Digestion efficiency is improved to 54.6% from 47.6%. Digestion gas production is increased from $0.30Nm^3/kg$ VS to $0.42Nm^3/kg$ VS.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.581-593
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• 1990

A semi-solid alloy in which solid and liquid phase are co-existing is obtained by strirring of Al7075 molten metal. A semi-solid alloy is dependent on the corresponding temperature within the solid-liquid range, and the process parameters should be controlled accurately to obtain the homogeneous semi-solid alloy. The possibility o homogeneous fiber-reinforce aluminum alloy by addition of $Al_{2}$O$_{3}$ short fibers with vigorous agitation was investigated. The billet of composite materials was fabricated by squeeze casting, and homogeneous dipersion state of fibers in billet of fabricated metal matrix composites was observed. A slurry of semi-solid short fiber metal matrix composites is used in the direct rolling process, and this process showed the fabrication possibility of metal matrix composite sheets. The fabricated sheet was tested regarding vickers hardness, elongation and micro-structure. It has become clear that mashy state processing and working are very useful to obtain parts of composites material closed to near net shape.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.491-505
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• 1993

The influences of protease on the removal of various protein soils from cotton fabrics were studied. The human epidermal stratum corneum, hemoglobin and casein were used as protein soils. The soiled fabrics were denatured by steaming for 30 min. before washing and laundered using Terg-O-Tometer under washing conditions. The removal efficiency was evaluated by analysis of protein on the fabrics before and after washing by means of copper-Folin method. The relations between the removal and the characteristics of protease were discussed. Also the degradation of protein were examined by microscopy. The seperation of human epidermal stratum corneum after hydrolysis was examined by SDS-PAGE. The results obtained were as follow : 1. The protein from the soiled cotton fabric was removed effectively by adding protease. The removal of protein was increased in proportion to increasing of the enzyme concentration up to a certain point, but it began to decrease above the point. The removal effect was high in the order of casein>human epidermal stratum corneum>hemoglobin. Especially the protein was more effectively removed in ADS solution(pH 9.5) containing enzyme. 2. When protease was used with ADS. the removal of protein was efficiently showed in relatively short time(5~15min.) compared to using ADS only. It is due to the properties of this enzyme that reacts with very short time. 3. Even at low temperature the removal efficiency of enzyme was relatively higher compared with the activity of enzyme. The removal of protein soil was increased up to a maximum near $50^{\circ}C$, and then decreased. 4. The removal of protein by protease was improved with the increase of alkalinity in the pH range from 9.5 to 11.0 but it began to decrease above pH 11.0. 5. According to the increase of mechanical agitation, the removal effect was increased. But the removal efficiency of protease was more effective compared with the agitation in detergency. 6. According to the SDS-PAGE separation and micrograph it was confirmed that the human epidermal corneum was effectively hydrolysed by the enzyme added. So the fragments of protein were removed more efficiently by means of the interfacial reaction of AOS.

• Tuberculosis and Respiratory Diseases
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• v.73 no.3
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• pp.151-161
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• 2012

Background: Adequate assessment and control of sedation play crucial roles in the proper performance of mechanical ventilation. Methods: A total of 30 patients with various pulmonary diseases were prospectively enrolled. The study population was randomized into two groups. The sedation assessment group (SAG) received active protocol-based control of sedation, and in the empiric control group (ECG), the sedation levels were empirically adjusted. Subsequently, daily interruption of sedation (DIS) was conducted in the SAG. Results: In the SAG, the dose of midazolam was significantly reduced by control of sedation (day 1, $1.3{\pm}0.5{\mu}g/kg/min$; day 2, $0.9{\pm}0.4{\mu}g/kg/min$; p<0.01), and was significantly lower than the ECG on day 2 (p<0.01). Likewise, on day 2, sedation levels were significantly lower in the SAG than in the ECG. Significant relationship was found between Ramsay sedation scale and Richmond agitation-sedation scale (RASS; $r_s$=-0.57), Ramsay Sedation Scale and Bispectral Index (BIS; $r_s$=0.77), and RASS and BIS ($r_s$=-0.79). In 10 patients, who didn't require re-sedation after DIS, BIS showed the earliest and most significant changes among the sedation scales. Ventilatory parameters showed significant but less prominent changes, and hemodynamic parameters didn't show significant changes. No seriously adverse events ensued after the implementation of DIS. Conclusion: Active assessment and control of sedation significantly reduced the dosage of sedatives in patients receiving mechanical ventilation. DIS, conducted in limited cases, suggested its potential efficacy and tolerability.

• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.600-627
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• 2016

Korea is one of the countries with a large veterinary antibiotics market, although antimicrobial resistance in bacteria is becoming a serious issue in many countries. The Korean government started to take interest in estimating the effects of livestock manure on rivers and agricultural soils and in monitoring of heavy metals, organic pollutants and antibiotics in the ambient water and soil. In this paper, pre-treatment methods to separate the selected antibiotics from solid samples were reviewed. It is essential to select an efficient and appropriate procedure for pre-treatment due to the high proportion of proteins and organics in biosolid samples. Pre-treatment consists of extraction followed by clean-up. Initially, homogenized samples were extracted by sonication, mechanical agitation or pressurized liquid extraction with methanol/acetonitrile/water mixture under acidic/basic conditions depending on the compound. However, aminoglycosides and colistin were extracted with 5% trichloroacetic acid and HCl, respectively. Since the ${\beta}-lactams$ are easily decomposed in acidic and basic conditions, they were extracted in neutral pH. Filtration with a membrane (pore size, $0.2{\mu}m$) or solid phase extraction with HLB and methanol, as eluents, was normally applied for the clean-up. At least, three different pre-treatment procedures should be adopted to screen all the selected antibiotics in solid samples.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.6
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• pp.289-294
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• 2017

Films fabricated using atomic layer 2-dimensional nanosheets exhibit various physical properties depending on the size of the nanosheet. This is because the physical properties of the film depend on the interfacial properties between the sheets. Therefore, the synthesis of large-sized nanosheets is very important because it can reduce the dependency of the film on the interfacial properties. In this study, we succeeded in fabricating $TiO_x$ nanosheets with atomic layer thickness over micrometer size by using single-crystallized starting material and its chemical exfoliation. In addition, it was revealed that the mechanical agitation speed (the stirring speed of a magnetic bar) during the exfoliation step using the organic material is closely related to the nanosheet size and the colloidal concentration of the nanosheets.