• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.205-208
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• 2001

The bitterness of brewers yeast slurry decreased by washing with mild caustic soda solution followed by washing with 0.85% (w/v) NaCl solution The higher concentration of caustic soda was, the lower the bitterness unit(BU) of washed yeast slurry was. The lethal rate of yeast cells increased. When the concentration of caustic soda solution increased from 0.05%(w/v) to 0.25%(w/v), the BU of brewers yeast slurry was decreased from 45 to 3, but yeast cells viability decreased from 93% to 0%. The optimum washing conditions of brewers yeast slurry were as follows: the concentration of caustic soda solution was $0.07{\sim}0.1%$(w/v) and the contact time of brewers yeast slurry with caustic soda was $10{\sim}20$ minutes. The similar washing effect was obtained when the brewers yeast slurry was washed with 20%(v/v) ethanol solution.

• Food Engineering Progress
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• v.23 no.2
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• pp.112-117
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• 2019

The purpose of this study is to develop a method to cultivate lactic acid bacteria (LAB) as a by-product in the fermentation of kimchi through the use of Chinese cabbage leaves. A method to reduce the initial number of microorganisms using citric acid and ethanol to wash cabbage leaves was investigated. In this experiment, Chinese cabbage leaves were washed using a mixture of 3% citric acid and 7% ethanol and the washed cabbage leaves were juiced and used as a sample. The total microorganisms of kimchi cabbage juice (KCJ) was reduced from log 6.53 CFU/g to log 3.69 CFU/g by washing with citric acid and ethanol, and lactic acid bacteria from log 4.40 CFU/g to log 2.01 CFU/g. The salinity of KCJ was appropriate for the growth of lactic acid bacteria but the pH was too low. The yield of washing, juice extraction, and total were 80.82%, 79.32%, and 64.11%, respectively. KCJ made by washing with citric acid and ethanol was good for the culture broth of lactic acid bacteria.

• 대한세포병리학회:학술대회논문집
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• 1993.06a
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• pp.25-26
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• 1993

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.2
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• pp.103-108
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• 1997

A series of batch tests were conducted to evaluate the design parameters for the application of soil washing techniques to the hydrophobic organic compounds (HOCs)-contaminated soil using mixed surfactants. Because the mixed surfactants form different structures of molecular aggregates from single surfactant, they were applied to improve the washing efficiency. Kinds of surfactants added, mixing ratio, and total concentration of mixed surfactants were evaluated. The uncontaminated soil was obtained from a country hill near Nock-Chun Station in Seoul. The portion of soil passing #4 (4.75 mm) sieve was used. The pH, organic contents and cation exchange capacity were 4.4, 1.6% and 4.08 meq/100 g, respectively The soil was artificially contaminated by n-dodecane. The 5% solution of OA-5 and OA-14 (1:1) showed 86% washing efficency. The 4% solution of SDS and OA-5 (1:1) showed 95% washing efficiency.

• Journal of the Korean Arthroscopy Society
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• v.12 no.2
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• pp.125-128
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• 2008

Purpose: The object of this study is to compare the clinical results of noraml saline and Lactated Ringer's solution in the arthroscopic meniscus surgery on the knee. Materials and Methods: The study group included 64 patients who had an medial meniscus tear and received arthroscopic partial medial meniscectomy. The group I was normal saline group, which was used as an irrigation solution during operation. The group II was Lactated Ringer's solution group. We measured the visual analogue scale, painless active knee flexion angle, and the ratio of the knee swelling at postoperative one day for all patients. Results: The visual analogue scale and the painless active knee flexion angle were no significant differences in comparing with normal saline and Lactated Ringer's solution group. The ratio of the knee swelling in Lactated Ringer's solution group was significantly less than those of noraml saline group. Conclusion: Lactated Ringer's solution has an advantage of decreasing the knee swelling in the arthroscopic meniscus surgery on the knee.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.65-74
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• 1998

To enhance the washing efficiency of soil polluted by hydrophobic organic compounds, the effects of electrolytes and monomeric organic additives on micelle formation and washing efficiency of mixed surfactant solutions were investigated in this study. The surface tensions and critical micelle concentrations(CMCs) of the single and mixed surfactant solutions[$POE_5$/SDS] supplemented by NaCl were measured to investigate the effects on washing efficiency, and the composition ratios of surfactants and NaCl were optimized for the efficient soil washing system. As the mixing ratio of $POE_5$/SDS was increased to 80%, the mixed surfactant with 0.01M NaCl showed more proportional increase of washing efficiency than the mixed surfactant without any salts. The 3% solution of $POE_5$ and SDS(80%/2o%) with 0.01M NaCl showed the washing efficiency of 90%. However, the washing efficiency was not enhanced by NaCl addition to the single surfactant solution of $POE_5$. The CMC of SDS(0.049%) was higher than that of $POE_5$(0.016%), but the CMCs of mixed surfactants were decreased as the mixing ratio of $POE_5$ was increased. Alcohols having longer chain and branched carbon chain were found to be desirable for the soil washing additives.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.99-107
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• 1997

In this study, a series of batch-scale tests were conducted to optimize the design parameters for the application of soil washing techniques to the hydrophobic organic compounds(HOCs)-contaminated soil and to find the effective methods for the recovery of surfactants from washing effluent by using solvent. Several nonionic surfactants (polyoxyethylene oleyl ester) and sophorolipid were applied to the artificially contaminated soil (4,000 mg n-dodecane/kg dry soil). The effects of washing time, concentration of surfactant solution, dilution ratio, and temperature on washing efficiencies were examined. Hydrophile-liphophile balance (HLB) number was proven to be one of the important parameters for soil washing. The HLB numbers of OA-5 and sophorolipid are too low to form a stable soil-water emulsion. They showed very low washing efficiencies less than 10e1o. If HLB number is in the proper range to form a stable soil-water emulsion, surfactant having higher solubility for HOCs shows higher washing efficiency. OA-14 having higher HLB number than OA-9 formed more stable soil-water emulsion. But its washing efficiency was about 20% due to a lower molar solubility ratio (MSR) than OA-9. OA-9, which forms a stable soil-water emulsion and has comparatively high sotubility for HOCs, showed about 60% washing efficiency by itself. To recover anthracene effectively from OA-9 washing effluent by using benzene as an organic solvent, desirable temperature and pH were $30^{\circ}C$ and 2, respectively.

• Resources Recycling
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• v.30 no.5
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• pp.38-48
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• 2021

In this study, we determine the optimal process conditions for selectively recovering Si from a solar cell surface by removal of impurities (Al, Zn, Ag, etc.). To selectively recover Si from solar cells, leaching is performed using HCl solution and an ultrasonic cleaner. After leaching, the solar cells are washed using distilled water and dried in an oven. Decompression filtration is performed on the HCl solution, and ICP-OES (Inductively Coupled Plasma Optical Emission spectroscopy) full scan analysis is performed on the filtered solution. Furthermore, XRD (X-ray powder diffraction), XRF (X-ray fluorescence), and ICP-OES are performed on the dried solar cells after crushing, and the purity and recovery rate of Si are obtained. In this experiment, the concentration of acid solution, reaction temperature, reaction time, and ultrasonic intensity are considered as variables. The results show that the optimal process conditions for the selective recovery of Si from the solar cells are as follows: the concentration of acid solution = 3 M HCl, reaction temperature = 60℃, reaction time = 120 min, and ultrasonic intensity = 150 W. Further, the Si purity and recovery rate are 99.85 and 99.24%, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.23-30
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• 2014

Purpose: The present study was aimed to figure out the correlation amongst the evaluation methods for critical micelle concentration, surface tension and protein cleaning efficacy to evaluate cleaning efficacy of contact lens care products. Methods: The critical micelle concentration of surfactants and the actual concentration of surfactants in contact lens care solutions were investigated by employing references published and related information. Surface tension of contact lens care solutions was measured by surface tension device at $25{\pm}1^{\circ}C$, and contact lenses made of lotrafilcon A, comfilcon A and balafilcon A were washed with contact lens care solutions after the incubation in artificial tears for 14 days and their cleaning efficacy was compared. Results: Among the 22 contact lens care products, 9 products provided the label of the concentration of surfactant, and 7 products showed higher concentration of surfactant than the critical micelle concentration reported in references. As a result of measuring surface tension, the surface tension of lens care products for soft contact lens was generally lower than other care products. When examined the removal effect of protein deposited on lens surface, it was known that the care products having lower surface tension showed higher protein removal efficiency. Conclusions: The surface tension is low when surfactant concentration in contact lens care solutions is high, and the removal effect of protein deposited is accordingly increased with the decrease of surface tension. Thus, these indicate the correlation amongst the evaluation methods for cleaning efficacy.

• Food Science and Preservation
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• v.17 no.3
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• pp.405-409
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• 2010

Surface cleaning is both essential and troublesome when a consumer seeks to eliminate soil attached to the surface of fresh ginseng because all ginseng purchased in the market is covered with soil, reflecting the post-harvest situation. To facilitate ginseng use at home, a fresh-cut type of ginseng is required. As a first step toward production of such ginseng, several washing and dipping treatments were investigated with respect to surface cleaning and reduction of microbial populations on fresh ginseng. In terms of microbial distribution on the surface of fresh ginseng, higher levels of viable bacteria (6.63 log CFU/each) and fungi (5.12 log CFU/each) were present on the rhizome head than on other regions of the root. Of the washing treatments tested, hand-brushing was effective for surface cleaning and to reduce microorganism levels on fresh ginseng, but use of a high-pressure water spray followed by hand-brushing was optimally effective. To further reduce the levelsof microorganisms on the surface of fresh ginseng after washing, additional dipping treatments in 70% (v/v) ethanol and electrolyzed acidic water (at pH 2.3) were somewhat effective but showed no significant differences compared with other dipping treatments tested, including a 3 ppm ozone solution, a 200 ppm sodium hypochlorite solution, or hot water at $50^{\circ}C$.