• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.105-112
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• 2005

Stabilizing and rousing sludge water generated from washing truck mixer and batcher plant can resolve inconsistency in quality and improve strength, therefore it is essential to review how to utilize it. This research conducted experiments and studied on solids of sludge water to find out the types of stabilizing agents available in conditions of producing ready mixed concretes in Korea. The result showed that oxy carboxylic acid retarder dedicated for stabilizing sludge water was most effective in decreasing solid. However, the setting time of cement paste was retarded due to surplus reactants, but it did not impede application of ready mixed concretes. When we left the sludge water mixed with stabilizing agent, it has been noted that initial retard effect recovered to the level using just service water in 7${\~}$8 days and that it is effective to use stabilized sludge water in 2${\~}$3 days. On the other hand, saccharic type super retarding agent was also outstanding in applicability by showing similar effect. The sludge water stabilizing agents currently marketed depend on imports, therefore it is necessary to locally manufacture usable stabilizing agents and to review its usability with multi-dimensional view.

• Tuberculosis and Respiratory Diseases
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• v.40 no.1
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• pp.29-34
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• 1993

Background: The development of the flexible fiberoptic broncoscope by Ikeda was an important technologic advance in the diagnosis and management of patients with pulmonary disease. But, cross contamination related to fiberoptic bronchoscope was reported in cases involving tubercle bacilli, MOTT and other agents. Therefore, cleaning and disinfecting of fiberoptic bronchoscope requires careful attention. Methods: From September 1991 to May 1992, medical records of all patients with positive culture for MOTT in bronchial washing specimens were reviewed. Also to evaluate bactericidal effect of 2% glutaraldehyde, culture was performed after inoculum of MOTT, Serratia marsescens and Pseudomonas aeruginosa to the disinfectant solution. Results: In 2% alkaline glutaraldehyde, MOTT was not survived only after 30 minute exposure, but P. aeruginosa and S. marsescens were rapidly inactivated with no survivors after exposure to 2% glutaraldehyde. Since vigorous mechanical cleansing and more than 30 minute of contact time within washing machine, no more outbreak was observed. Conclusions: It is also very important that bronchoscopes must be meticulously cleaned after each procedure and more than 30 minute exposure would be required for eradication of MOTT with 2% glutaraldehyde. However even the most strictly applied infection control measures cannot exclude contamination completly and clinicians have to stay alert to this possibility. Prompt detection of pseudoepidemics is possible if abrupt increase in isolation rates, especially if they involve unusual or generally nonpathogenic organisms, are readily recognized.

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.849-863
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• 2009

Objectives : This study was to study dental hygiene department students' management of infection and their attitude toward infection. Methods : This study was conducted from August 24, 2009 to September 20, 2009. 269 sophomore and junior college students enrolled in the department of dental hygiene from schools located in Gyeonggi-do and Gangwon-do participated in the study. A self-administered questionnaire survey was conducted. Results : 1. As for dental hygiene department students' recognition of the causes of infectious diseases, 80.7% of the respondents said hepatitis B was the infectious disease highly likely to occur in laboratories. 35.3% was correct about the antecedent variables of infection in the workshop, 24.9% about the oral symptoms of HIV and 18.6% about the diseases induced by HBV. The recognition rates were generally low. 2. About whether the respondents ask patients questions about infectious diseases, 80.7% of them answered Yes, but only 56.2% of them said they do so every time, and 17.8% of them said they never do so. 3. As far as washing hands to prevent infectious diseases is concerned, 97.4% of the respondents said hand washing helps prevent infection. 72.5% of them said they wash their hands every time before they practice on a patient, while 84.0% of them said they washed their hands after the lab practice. 90.7% said they use liquid soap containing anti-microbial agents, and 81.8% of them said they use paper towels. 4. With regard to protective gear for prevention of infectious diseases, 98.9% of the respondents said it is desirable to use disposable protective gear for each patient. When it comes to what they actually used as protective gear, 91.1% said aprons, 89.2% gloves, and 87.7% masks. However, a low percentage of the respondents actually use goggles and replace masks when they got damp, 11.2% and 24.2% respectively. Conclusions : As for treating the surface of equipments to prevent infectious diseases, most of the respondents exhibited a high recognition rate. Relative fewer respondents actually treat the surface of equipments than those respondents who are aware of the need to do so. A high percentage of the respondents also said they use alcohol sponge to treat the surface of each equipment in order to prevent infectious diseases.

• Journal of the Korean Society of Clothing and Textiles
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• v.7 no.2
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• pp.19-25
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• 1983

The purpose of this study was to investigate the effects of laundry variables and additives on the removal of deposited calcium on the cotton fabric. Samples of calcium deposited fabric was made by treating fabric with $CaC1_2$ and $Na_2CO_3$ solution subsequently. The experimental variables were: 1) NaOH concentration ($0.0001\%$, $0.0005\%$, $0.001\%$, $0.005\%$, $0.01\%$) 2) Alkaline builders(sodium carbonate, sodium meta silicate) 3) Sequestering agents(STPP and EDTA concentration: $0.02\%$, $0.04\%$, $0.06\%$, $0.08\%$, $0.1\%$, $0.15\%$, $0.2\%$) 4) Temperatures($25\pm1^{\circ}C$, $40\pm1^{\circ}C$, $60\pm1^{\circ}C$) 5) Edge-abrasion to the removal of deposited calcium on the cotton fabric. The fabric was washed for 15 minutes in a washing machine(Model: Gold Star WP-3007) or Launder-0-meter(40$\~$45 r.p.m., Toyo Rika Instrument Inc.) and rinsed 3 times per every rinsing time. The amount of calcium deposits on the fabrics was determined by EDTA-back titration methods and edge-abrasion was evaluated by ASTM D 3886 method. The results of this study were as follows: 1) pH of surfactant solution(NaOH concentration) did not influence on the removal of deposited calcium on the cotton fabric. 2) Added alkaline builders did not influence on the removal of deposited calcium on the cotton fabric. 3) It was shown that STPP and EDTA were effective to remove deposited calcium. The removal of deposited calcium on the cotton fabric was proportionally increased with increasing concentration of STPP and EDTA. At high concentration, however, the rate was rather decreased with increasing concentration. 4) The temperature of washing solution did not influence on the removal of dedosited calcium on the cotton fabric. 5) As the removal of deposited calcium on the cotton fabric was increased, the rate of edge-abrasion of the fabric was gradually increased.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.193-199
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• 2020

The effects of the composition of the dishwashing detergent on interfaces of the oil (O) and the aqueous (W) solution in addition to the cleaning effects of interfacial properties were investigated. Also, the cleaning power of the oil contaminated on the surface of the dish according to each composition and the residuals of the contaminants and the cleaning agent after the washing rinses were evaluated. The removal of contaminated oil on the solid (S) surface in the composition of the cleaning agents used in this study was strongly related to the interfacial properties between the W/O/S, and was particularly dependent on the forward and backward dynamic contact angles. When both contact angles were low at the same time, the permeability of the cleaning solution was so high that the contaminated oil showed a high removal effect. The smaller the interfacial tension of O/W was, the better emulsification of the contaminated oil, the higher the interfacial tension, and the poorer emulsification were achieved. However, the emulsification effect did not significantly affect the cleaning power. In particular, in the case of the cleaner having low interfacial tension, the cleaning material remained on the surface of the solid after washing.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.584-594
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• 2014

To increase of surface hydrophilicity of polymeric thin films is an important approaching technique for introduction of self-cleaning and/or antifogging properties on the surfaces of those films. In general, hydrophilic surface can be produced by coating non ionic surfactants or by increasing surface energy. Various non-ionic surfactants, such as Tween, Span, and PEG-PPG block copolymers were selected for our experiments, because they are cheap and well soluble in toluene system as well as they contain several reactive hydroxy fuctional groups with coupling agents. Blending conditions influence the PET film surface hydrophilicities. However, the introduction of only these surfactants on the surface of PET films did not show the high durability of hydrophilic properties after washing with water. To improve the durability two types of coupling agents such as epoxide and diisocyanate were adopted. Contact angle of water on hydrophilically coated PET film surface with 6 wt% of isophrone diisocyanate(IPDI) containing coating solution was reached to $8.7^{\circ}$, which was an indirect evidence for very high surface hydrophilicity. A light(500 nm of wavelength) transmittance value of coated PET film was changed only from 87% to 85% with keeping a good transparent property. This film can be usable for self-cleaning film industries.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.6
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• pp.788-799
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• 1999

This study was performed to investigate the effect of mordants on the dyeability colorfastness to light and to laundering and biological properties of mordanted and natural-dyed cotton and silk substrates. Natural red dyes were extracted from Caesalpinia Sappan L. (Sappan wood) and Rubia Akane Nakai (Madder) by boil water Five different compounds of Al, Cr, Cu, Fe and Sn were used as mordanting agents. The result of this study are sumarized as follows ; 1. In the of the fabrics mordanted and dyed with sappan wood K/S value increases and λmax shifts to the longer wavelength as mordant concentration increases. Color of the fabrics dyed with sappan wood and madder change to redder bluer and lighter after mordanting. 2. As the number of repetition of dyeing-mordnating process increase the color of the dyed fabrics tend to be redder bluer and darker. Mordanted dyes with Al and Sn make chroma increase. The quantity of mordant absorbed in the silk fabric increase as mordant concentration increase. More Fe is absorbed in silk than Cr is. 3. After being exposed to light the fabrics dyed with sappan wood and madder change to less red Fe and Cu mordanting yeild better colorfastness to light than others does. Natural-dyed fabrics exposed to light tend to be faded and whitened in CIELAB chromaticity co-ordinates. So we might trace back the original color of ancient faded fabrics by changes in color of natural dyes. 4. After washing the colors of natural dyes change to more blue, Fe and Cu mordanting give better colorfastness to wash than others do. 5. The soil-burial cotton is more susceptible to mildew and rot than the silk is. Antimicrobial activity of the natural-dyed cotton can be enhanced by Cu and silk can be enhanced by Cu and Cr mordanting respectively.

• Journal of Korean Public Health Nursing
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• v.5 no.2
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• pp.67-75
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• 1991

This study was conducted to evaluate the difference of staphylococcal colonization between lactating mothers and nursery stares. Samples were obtained from the hands and noses of the newborn(admitted to S Univ. hospital's nursery from 1991. 5. 23 to 6. 8), their mothers and nursery staffs. They were cultured, and then the presence/absence of pathogenic staphylococci in them were analyzed by Fisher exact probability test which led to these conclusion of significance as follows: 1. No differences were detected in pathogenic rate of nasal swab culture between breast~fed newborns and formula-fed ones. 2. Delivery type and hospitalization the ones from the brest-fed newborns show high rate of Sta. aureus coa(+). In case of either C-sec delivery or long (more than 4 days) hospitalization, formula-fed ones in case of NSVD or short (less than 3 days) hospitalization. 3. The ones from breast feeding mothers show higher sta. aureus coa(+) than those from nursery staffs, which was of no significance statistically. Considering nursery staffs only, however, the comparison of those with the data in April indicates that the pathogen rate is higher for hand than nose, and Sta aureus coa(+) for hand is far lower in June than in April, which was statistically significant. These results lead us to infer that newborn infection in hospitalization could be largely reduced by maintaining the ordinary hygienes. Such as the handwashing of mothers as well as nursery staffs (directly involved in newborn care) Thus the pre-enterance hand washing of a mother who visits the nursery only for breast feeding (without any other medical responsibility) should be done, like other medical agents, with $0.05\%$ chlorhexidine antiseptics rather than simple soap cleansing; the one 'that is worth emphasizing thoroughly.

• Journal of Korean Neurosurgical Society
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• v.46 no.2
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• pp.123-129
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• 2009

Objective: This study was aimed to identify the incidence and risk factors of vancomycin-resistant enterococcus (VRE) colonization in neurosurgical practice of field, with particular attention to intensive care unit (ICU). Methods: This retrospective study was carried out on the Neurosurgical ICU (NICU), during the period from January. 2005 to December. 2007, in 414 consecutive patients who had been admitted to the NICU. Demographics and known risk factors were retrieved and assessed by statistical methods. Results: A total of 52 patients had VRE colonization among 414 patients enrolled, with an overall prevalence rate of 6.1%. E. faecium was the most frequently isolated pathogen, and 92.3% of all VRE were isolated from urine specimen. Active infection was noticed only in 2 patients with bacteremia and meningitis. Relative antibiotic agents were third-generation cephalosporin in 40%, and vancomycin in 23%, and multiple antibiotic usages were also identified in 13% of all cases. Multivariate analyses showed Glasgow coma scale (GCS) score less than 8, placement of Foley catheter longer than 2 weeks, ICU stay over 2 weeks and presence of nearby VRE-positive patients had a significantly independent association with VRE infection. Conclusion: When managing the high-risk patients being prone to be infected VRE in the NICU, extreme caution should be paid upon. Because prevention and outbreak control is of ultimate importance, clinicians should be alert the possibility of impending colonization and infection by all means available. The most crucial interventions are careful hand washing, strict glove handling, meticulous and active screening, and complete segregation.

• Textile Coloration and Finishing
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• v.11 no.1
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• pp.16-24
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• 1999

The effects of two-step fixation of steaming and baking on the dischargeability of cotton fabrics dyed with C.I. Reactive Black 5(Bl-5) were investigated when the concentrations of $K_2CO_3$ and benzaldehyde sodium bisulfite(BASB) were increased over 120/kg. Remarkably increased dischargeability resulted from baking for 3 min or more at 160t after steaming for 8 min or more at $102^\circ{C}$, but 120g/kg or more amounts of $K_2CO_3$ and BASB(50%) had little influence on dischargeability. Therefore the discharge mechanism can be suggested that covalent bonds between cellulose and Bl-5 undergo $S_N2$ attack by hydroxide ion formed by the reaction of $K_2CO_3$ and water in steaming at $102^\circ{C}$ first and then, through transition states they are cleavaged in baking at 160t to yield hydrolyzed Bl-S and compounds of BASB and Bl-5 isolated from fiber, which are undyeable and removed by washing. The effect of urea, one of the hydrotrope agents, on discharge printing was also studied. The result which dischargeability was greatly improved by increasing the steaming time from 8 min to 15 min at $102^\circ{C}$ or by increasing the amount of urea obviously shows that water in steaming and urea in print paste play an important role in discharge printing. And as an increase of the baking time from 5 min to 7 min at $160^\circ{C}$ makes it possible to improve dischargeability, it is once more confirmed that high temperature of about 160t is exactly required to discharge the dyed Bl-5. The colored discharge printing demands a more amount of urea because urea contributes to the putting color fixation as well as the discharge reaction.