• Journal of environmental and Sanitary engineering
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• v.16 no.2
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• pp.38-46
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• 2001

In this work, the heterogeneous ion exchange membrane was used in a electrodialysis apparatus to treat a Ni planting rinse water because the heterogeneous ion exchange membrane was excellent efficiency as compared with low manufacturing cost, was easy to make, and had a good mechanical properties. For a regeneration of membrane and to obtain the optimal condition for a scale-up of apparatus after treating Ni plating rinse water, we would find about the limiting current density and the concentration polarization. When the Ni plating rinse water 150mg/L was treated with the electrodialysis apparatus using the heterogeneous ion exchange membrane, the limiting current density was about $1.49{\;}mA/\textrm{cm}^2$. And the limiting current density increased with the flow rate and concentration of Ni plating rinse water. We recognized that the used membrane could be reused by periodic backwashing because efficiency was constant when the membrane was backwashed after treating wastewater.

• Korean journal of food and cookery science
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• v.21 no.5
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• pp.703-708
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• 2005

The purposes of this study were to establish washing conditions for vegetable salad to reduce the microbial hazard by using sodium hypochlorite solution and eventually to implement HACCP for salad processing. By using the salad production line of Shinkeum Co. located in Gwacheon, Gyunggi-do, salad samples were washed under several washing conditions (chlorine dip period, chlorine concentration, rinse time, etc.) to determine the most effective conditions. The original washing line consisted of 3 baths (100 ppm chlorine water dip, water rinse, and water rinse), each with a capacity of 100 L of tap water and 5 kg of salad. First, the salad samples were washed with 100 ppm of sodium hypochlorite solution for various dip times (3, 6, 9, 12 min); however, only a 1 log- or less-reduction in total microbial counts was achieved in all groups and the time of chlorine water dip was not a significant factor in reducing the microbial hazard. When another water bath was added before the chlorine water dip (4-bath washing), a 2 log-reduction in total microbial counts was achieved. This result suggested the importance of pre-dipping salad materials in water before chlorine treatment to reduce the organic load on the surface of the vegetables. Coliforms were not detected at all after washing. As the concentration of chlorine $(50{\sim}150\;ppm)$ and rinse time $(0.5{\sim}2\;min)$ increased, greater microbial reduction was achieved; however, physical damage of the salad was observed. Finally, the optimum washing conditions for salad were determined as 3 min-water dip, 3 min-chlorine (100 ppm) dip, 2 min-rinse, and 2 min-rinse.

• Journal of the Korean institute of surface engineering
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• v.36 no.2
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• pp.194-199
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• 2003

Polarization measurements were peformed to investigate the electrochemical behavior of copper ions and limiting current density in waste rinse water from copper electroplating processes. A newly designed cyclone type electrolyzer was tested to recover the copper powder. Synthetic solutions were prepared using analytical grade $CuSO_4$ to the desired waste water concentration and pH was adjusted with $H_2$$SO_4$. Electrowinning was peformed at room temperature and the solution was cycled with a pump. Results showed that more than 99 percent of Cu was recovered and the size of the recovered Cu powder ranges from 0.1 - $0.5\mu\textrm{m}$. The chemical composition of the Cu powder mainly consists of $Cu_2$O and Cu and can be easily reduced to pure Cu powder.

• Journal of the Korean Society of Fashion and Beauty
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• v.4 no.3 s.9
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• pp.13-17
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• 2006

Perm is one the of the most common thing in a beauty salon like hair-cut and hair perm needs processing solutions which is chemical substances. Those chemical substances damage the hair cuticle. Damaged hair cuticles with mistakes of perm will follow with the next performance and it will cause more damage to hair. As damage of hair cuticle become worse, it is harder to recover the hair cuticle like before. Therefore, this study shows that plain rinse is the way to reduce the damage of hair cuticle with perm as much as possible. With experiments, I suggest the right way to do plain rinse to satisfy customers' demand and reduce the damage. During the research, I figured that plain rinse with the knowledge, structure of hair cuticle, principle of perm and plain rinse, is very needed. The hair with plain rinse have more elastic curl and have less scales which came off from hair cuticle than the hair without plain rinse. This experiment concludes that hairdresser has to figure out about the time, temperature and type of water depends on the degree of damaged hair of customers. In order to perm, there is no way to not to use chemical substances to perm. Therefore, hairdresser has to choose suitable processing solutions and right steps, and as this is the age of 'well-being' boom, hairdresser must try to keep the healthy hair. Consequently, in order to meet the demands and conditions of customers, hairdresser needs to find the right method to do plain rinse and use the method in perm.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.423-431
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• 1975

The purpose of this investigation was to study whether limewater can be used as dairy detergent-sanitizer for dairy farm euipment compared with idophore in the milking machine. 1. Milkstone deposition was increased slightly by idophore and limewater pre-rinse but seriously increased by milking without pre-rinse for 6 days milking. 2. Milkstone deposition was increased by increasing temperature of pre-rinse sanitizer solutions. 3. Limewater rinse was more effective than idophore rinse and tap water rinse in removing butterfat. 4. Idophore and limewater rinse was more effective than tap water rinse in removing milk solid. 5. Both of idophore and limewater were found to be significantly effective for milk bactericidal. 6. It was conclused that good hygienic raw milk can be producesed from dairy farm by idophore and limewater per-rinse.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.2
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• pp.60-69
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• 1998

Polysilicon surface mdoification tecnique is developed to reduce the sticking of microstructures fabricated by micromachining. Modified anti-sticking grain holes are simply formed by two-step dry eth without additional photolithography nor deposition of thin films. Both process-induced sticking and in-use sticking are successfully reduced more than two times by adopting grain holed polysilicon substrate. A sticking model for cantilever beam is derived. This model includes bending moment stems from stress gradient along the thickness directionof structural polysilicon. Because the surface tension of rinse liquid and the surface energy of the solids to be stuk tend to decrease in recently developed anti-sticking techniques, the effect of stress gradient will play an important role to analyze the sticking phenomena. Effect of the temperature during post-release rinse and dry is modelled and verified experimentally. Based on developed anti-sticking polysilicon structure and the sticking model, sticking of microstructure, fabricated by simple wet process including sacrificial layer etch and rinse with deionized water without special equimpment for post-release rinse and dry was alleviated more than 3.5 times.

• Polymer(Korea)
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• v.26 no.5
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• pp.551-558
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• 2002

It was observed that adsorption characteristics of sulfonated fabric ion-exchanger for separating nickel ion from electroplating rinse water. Swelling ratio was increased by increasing degree of sulfonation and polarity of solvent. Ion-exchange capacity was also increased by increasing degree of sulfonation and showed 3.38 meq/g at 16% sulfonated ion-exchanger. There was little effects of pH. Adsorption equilibrium was attained within 10 min, and adsorption rate was 7.5 mg/min. Adsorption capacity was not changed after 7 cycles of regeneration process. Regeneration adsorption capacity was slightly decreased to 2.01 meq/g. It confirmed that durability of sulfonated fabric ion-exchanger was suitable for adsorption process. Adsorption equilibrium time was linearly increased by increasing L/D and adsorption capacity showed the ion exchange capacity within the range of 2.71 ∼ 3.01 meq/g in continuous process. Design of adsorption column could be possible for L/D<2. Under constant L/D condition, there is no little pH effect when rinse water is acidic solution, and operation condition of adsorption process was optimized under pH 5.

• Journal of the Korean institute of surface engineering
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• v.8 no.2
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• pp.14-19
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• 1975

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.392-398
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• 1999

The purpose of this study was to assess the effect of catalase used following bleaching for the elimination of hydrogen peroxide residues from human teeth on the microleakage at the tooth-resin composite interface. In this study, class V cavities were prepared on the buccal or lingual surfaces of seventy extracted human molar teeth, and crown of sixty teeth were immersed in 30% hydrogen peroxide at $37^{\circ}C$ for 5 days except for negative control group. Then the teeth were rinsed with water and distributed randomly into seven groups of 10 each and were conditioned as following Negative control group: No bleaching Positive control group : bleaching and no application of catalase (C-40) Experimental group 1 : one cycle of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 2 : two cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 3 : three cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 4 : four cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 5 : five cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching The cavities of each groups were restored with composite resin. The teeth were thermocycled, stained with 2% methylene blue, and sectioned buccolingually. Degree of dye penetration at tooth-restoration interfaces were examined by stereomicroscope(${\times}30$) at occlusal and gingival margin The results were as follows : 1. On the occlusal margin, there was no significant difference in the microleakage between the negative coltrol group and experimental groups (p>0.05). But on the gingival margin, experimental groups showed higher microleakage than the negative coltrol group (p<0.05). 2. On the occlusal margin, positive coltrol group showed higher microleakage than experimental groups (p<0.05) and among the experimental groups, group 1 showed higher microleakage than group 3, 4, 5 (p<0.05). 3. On the gingival margin, there was no significant difference between the positive coltrol group and experimental groups, and between experimental groups (p>0.05). The result indicated that catalase used in bleached cavity for the elimination of hydrogen peroxide residues from human teeth maybe reduced microleakage at the tooth-resin composite interface.

• Proceedings of the Membrane Society of Korea Conference
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• 2001.11a
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• pp.111-114
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• 2001