• Journal of the Korean Society of Safety
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• v.11 no.4
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• pp.79-83
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• 1996

In this study, in attempt to develop a new application technique of discharge plasma, we employed a kind of discharging method called SPCP ( short for Surface discharge induced Plasma Chemical Process). Applications of SPCP have been widely used for years. Compact ozonizers to deodorize household equipments like refrigerators we a part of such applications. We took advantages of the compactness and durability of the SPCP electrode to set up an experimental apparatus for decompositing vapor of aromatic hydrocarbons such as toluene, benzene and xylenes, which are major substances given off In painting or washing processes and aggravate working conditions. Results obtained from this study are summarized as follows. 1) Aromatic hydrocarbon vapors of up to 2,000ppm were almost thoroughly decomposed at the flow rate of 4ℓ/min or lower under the discharge with electric power of 400 Watts. 2) In dry air, as the decomposition progresses, tar-like substance deposits on the discharging areas, which deteriorated the decomposition rate in the end. This substance, however, was almost thoroughly removed by keeping discharge in dry air containing no solvent vapor.

• Journal of Korean society of Dental Hygiene
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• v.9 no.3
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• pp.468-478
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• 2009

This research was performed to provide basic data for the development of infection related dental hygiene studies by surveying the current condition of recognition among students in the department of dental hygiene toward hospital infection management while receiving the following results by using a personal self-administered survey method targeting 303 students in the department of dental hygiene from certain areas. 1. With the current condition of recognition on the sanitization and sterilization of instruments among students in the department of dental hygiene(study), the rate at which surgical instruments are to be sterilized with autoclaves was 79.9% which was relatively higher than other instruments while it was shown that prosthetic instruments for treatment was 56.4%, conservative instruments for treatment was 51.8%, and ultrasonic scaler tip was 51.1% while the way syringe tips(36.1%) and the dental anesthetic apparatus(27.9%) were revealed to require sanitization by alcohol. 2. The 'hand wash' area was the highest with 4.71 while the 'materials and environment management' area and 'equipment management' area appeared high respectively with 4.43 and 4.41. 3. With the current condition of recognition on equipment management, 'equipments used for contagious patients are separately washed after a one-time use and must be sterilized or separated-and-discarded' was the highest with 4.82 while 'sterilization equipments with humidity or water on it are considered contaminated and are not used' showed the lowest recognition level with 3.90. 4. Regarding the current condition of materials and environment management, 'contagious and general trash are separated and discarded' was the highest with 4.70 while 'the refrigerator for medicine storage is cleaned on a regular basis once a month' was revealed as the lowest with 4.11. 5. With the current condition of recognition on hand washing, 'one must wash their hands after coming in contact with contagious patients, was the highest with 4.90 while washing hands after taking off gloves' appeared as the lowest with 4.51 point. To conclude department of dental hygiene there is to infection management and necessary about organization disinfecting and pasteurization to strengthen an education in order raising a stamp helping practical ratio about the infection management which whole, is from presence at a sickbed and connection does and about the infection management which is substantial and educational program development leads feed with the fact that deepening studying which is continuous must become accomplished becomes.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.238-241
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• 2010

The purification of indole from 54.3wt% indole fraction (temperature range of distillate: $250{\sim}255^{\circ}C$) recovered by extraction-distillation combination of coal tar fraction (temperature range of distillate: $240{\sim}265^{\circ}C$) was examined by solute crystallization. The feed consists of eight components such as quinoline, iso-quinoline, indole, quinaldine, 1-methylnaphthalene, 2-methylnaphthalene, biphenyl and phenyl ether. Hexane and an aqueous solution of methanol (50 : 50 vol%) were used as the crystallization solvent and the coolant, respectively. A batch stirred tank of glass material was used as a crystallization apparatus. By increasing the operation temperature and the volume ratio of solvent to feed at initial, the purity of indole increas ed, but yields of indole showed a decreasing tendency. Solute crystallization method using hexane as a solvent was excellent because the purity of 99.3 wt% indole was recovered at the yield of 50% without washing operation.

• Journal of Families and Better Life
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• v.23 no.6 s.78
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• pp.67-77
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• 2005

The purpose of this study was to evaluate the accessibility of existing multi-household multi-studio type house for developing Senior Congregate Housing. At present, in Korea, 'the Act of Promotion of Convenience and SEcurity for Disabled, Aged, Expectant Mothers, etc.' is applied to only public facilities. Therefore, this study evaluated 7 units -2 multi-household house and i multi-studio type house- in order to grasp the problems caused if the aged would dwell in that type of house, by the items of 'manual for improving the residency of the disabled' which was stipulated by the act above. The data was collected from May to June, 2005. The results were as follows: Firstly, the main entrances, exits and width of stairways had narrow spaces, the handles and bars did not conform with the terms presented in the manual above. Front doors should be opened like a bay for wheelchair use. Secondly, additional lighting apparatus and furniture should be added properly Thirdly, there were several inconformity to the manual for bathroom: improper handles, inadjustable washing-stands, unavailable spaces in front of toilet bowls, and out-of-place showers and taps. Finally kitchen cabinet design improper for wheelchair user. In conclusion, accessibility of existing multi-household or multi-studio type house was not good enough for the aged reside in. Those insufficiencies suggest that more specified standards to enhance accessibility to develop senior congregate housing should be added.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.77-83
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• 1981

The purpose of this study was to observe the bonding strength between tooth surface (enamel and dentin) and restorative filling materials which are two composite resins (Clearfil and Concise) and Glass ionomer cement, after etching with 50% phoshoric acid and 37% citric acid. To measure the bonding strength in enamel, the labial surface of upper anterior tooth was cut flatly with using carborundum disk and polished with sand paper disk, and to measure in dentin, the dentin surface was prepared by grinding upper part of posterior tooth horizontally. After washing the tooth surface with water and drying with air blast, the prepared tooth surface was etched. In glass ionomer cement, 50% phosphoric acid and 37% citric acid were used, in Clearfil 40% phosphoric acid was used and in Concise, 50% phosphoric acid and 37% citric acid were used as etchant for 1 minute. After the copper band which is 5 mm in diameter and 5 mm in height was fixed on the prepared surface and each filling material was inserted into the copper band, the hooking loop was inserted into filled material in the copper band before setting to make it easily that the load is applied on the specimen. After all specimens were immersed in water at $37^{\circ}C$ for 1 week, this specimen was placed on the load cell of tensile test apparatus, and specimen was pulled at the cross-head speed of 0.8 mm per minute. The following results were obtained 1) In glass ionomer cement, the bond strength obtained by 37% citric acid was higher than one obtained by 50% phosphoric acid in enamel and dentin surfaces. The bond strength obtained in non-etched surface was much less than one by etchants in enamel and dentin surface. 2) In Clearfil, the bond strength obtained by 40% phosphoric acid was 4 times more than one obtained by non etch ant. 3) In Concise, the bond strength obtained by 50% phosphoric acid was almost same as one obtained by 37% citric acid, and the bond strength obtained by non etch ant was much less than one obtained by etchants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.776-781
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• 2010

The properties and bactericidal activities of strongly acidic electrolyzed water (SEW) against food-borne pathogenic bacteria, vegetables and kitchen apparatuses were investigated. The available chlorine concentration, pH and oxidation reduction potential (ORP) of SEW were $35{\pm}1.2\;ppm$, $2.3{\pm}0.2$, and $1,140{\pm}20.4\;mV$, respectively. Five strains of food-borne bacteria with initial cell number of 7.00 log CFU/mL were not detected except Bacillus cereus after treatment with SEW for 60 sec. The numbers of Bacillus cereus were reduced to 2.08{\pm}1.00 log CFU/mL at the same condition. In vegetables, SEW treatment after washing strongly in alkalic electrolyzed water (AEW) showed better bactericidal effects than SEW only. The viable cell on stainless steel bowl ($3.86{\pm}2.49\;\log\;CFU/100\;cm^2$) and cup for water ($2.40{\pm}1.80\;\log\;CFU/100\;cm^2$) were not detected by SEW treatment (35 ppm of available chlorine concentration) for 30 sec, but survival of more than 1.00 log CFU/$100\;cm^2$ of viable cell was shown by washing of sodium hypochlorite solution at the same condition. On the other hand, the coliform group bacteria ($5.08{\pm}4.00\;CFU/100\;cm^2$) were detected on rubber globe only, and more than 2.00 log CFU/$100\;cm^2$ of viable cell and coliform group bacteria on it survived, though it was washed with flowing SEW for 30 sec.