• Title/Summary/Keyword: before washing

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Fabrication of Zirconium Phosphate Nanoparticles through Solution Technique (수용액법에 의한 인산 지르코늄 나노입자의 합성)

  • 정영근;최현규
    • Journal of Powder Materials
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    • v.9 no.5
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    • pp.336-340
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    • 2002
  • The $\alpha$-zirconium phosphate particles as fine as 20 nm were fabricated through solution technique using $ZrOCl_2{\cdot}8H_2O$ and $H_3PO_4$ as precursors. Stability of $\alpha$-Zirconium phosphate could be ensured by adding excess phosphoric acid to a stoichiometric composition Instead of using reflux route that resulted in coarsening of particles due to an inevitably long aging. The excess phosphorous incorporated in the crystal could be successfully eliminated afterwards through careful washing. Moreover, heavily agglomerated particles are observed before washing, but fairly dispersed state is found out after washing treatment. Thus, it is found that dispersed state as well as phase stability is ensured through proper washing treatment.

Percentage Motility before and after Processing by a Sperm Washing and Swim-up Method : Relationship to Outcome of Intrauterine Insemination (정자 세정후 Swim-up 처치가 정자의 운동성에 미치는 영향)

  • Lee, Yu-Il
    • Clinical and Experimental Reproductive Medicine
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    • v.18 no.1
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    • pp.89-94
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    • 1991
  • Thirty five couples were treated by intrauterine insemination with sperm prepared by a washing and swim-up method. Fifteen women conceived(42.9%). Sperm washing and swim-up was found to significantly improve sperm motility for men of infertile couples and the increment of percent sperm motility after sperm preparation allowed significant differentiation of pregnant and nonpregnant patients in asthenozoospermia(submotile) group (p<0.01). The author suggest that the increment of percent sperm motility after sperm washing and swim-up could be a useful screening tool for in vitro procedure proposed to improve fertility in the intrauterine insemination of asthenozoospermia.

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Effect of Fumigation on the Strength of Excavated Costumes (훈증처리가 출토복식유물의 강도 변화에 미치는 영향)

  • 채옥자;박성실;안춘순
    • The Research Journal of the Costume Culture
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    • v.12 no.4
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    • pp.591-598
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    • 2004
  • This study examines the effects and influences of fumigation using chemical composite of Methyl Bromide and Ethylene Oxide on the change of strength of excavated dresses. The fabric strength immediately after washing and fumigation increased slightly, but it decreased greatly as the time progressed. The strength of the test sample from Museum A showed a steady decrease with time, while that of Museum B decreased rapidly 5 months later. Compared with the non-fumigated sample, fumigated sample was greater in strength regardless of the time progression, and the strength of sample kept in the exhibit hall was greater than that kept in the storage room. The strength of the fumigated sample was almost same regardless of the three different time periods, before washing, after washing and immediately after fumigation, and it decreased steadily with time, whereas the non-fumigated sample became much weaker in its strength in 10 months after washing. Even 5 months later, the fumigated sample was about as strong as immediately after fumigation, but the strength dropped to a great extent 10 months later.

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Comparative study on the efficiency of pesticide residue removal in foods (Perilla Leaves, Strawberries, Apples)

  • Seung-Woon Myung
    • Analytical Science and Technology
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    • v.37 no.1
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    • pp.1-11
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    • 2024
  • In agricultural households cultivating vegetables and fruits, the use of various pesticides to protect crops from diseases and pests or to control weeds is widely practiced enhancing quality and productivity. However, pesticides can pose a threat to consumer health by remaining on the food surface or migrating into the food interior. Households commonly peel off skins, wash with water, or use chemical methods to remove foreign substances including residual pesticides on the food surface. In this study, we measured the washing rate by comparing the pesticide concentrations before and after washing in the leafy vegetable perilla leaves and the fruits strawberries and apples, which were intentionally exposed to pesticides. We compared washing rates using tap water, a baking soda solution, and a commercially available food-specific cleaning solution. The target pesticides for analysis were azoxystrobin, bifenthrin, boscalid, difenoconazole, flubendiamide, and indoxacarb, and the residual pesticide analysis was performed using GC-MS/MS or LC-MS/MS. The removal rates of pesticides were highest with the food-specific cleaner, followed by baking soda and tap water in order.

Microbiological Effect of Hand Safety after Hand Washing Education for Preschool Children in a Day Care Center (미취학 어린이의 손씻기 교육에 따른 미생물학적 실태 분석)

  • Kim, Ji-Eun;Moon, Ji-Hea;Shin, Hyun-Ah;Lee, Ji-Sun;Kwon, Sung-Hee;Lee, Jung-Sook;Om, Ae-Son
    • Culinary science and hospitality research
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    • v.17 no.3
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    • pp.141-150
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    • 2011
  • The objective of this study is to monitor the microbiological effect on preschool children's hand safety according to educational methods of hand washing. The subjects were ten children aged three to five. The analyses of the microbiological effect were made before band washing education, after one-week video demonstrations of hand washing education, and after one-week video demonstrations of hand washing education combined with practice. The results were as follows. Total plate count, filamentous fungi, coliform, and Staphylocuccus aureus were detected from children's hands just before band washing education. According to the two-week hand washing education, such education was found effective in keeping the children's hands clean and safe. In conclusion, repeated and more consistent training of band washing would be important for children, especially aged three to five because most of the habits and behavior patterns were developed in these age groups and the effects were persistent during their future life.

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Design Genealogy of Washing Machines and their Mechanism (세탁기 기본형 형성과 디자인 발전에 관한 연구)

  • 김원진;채승진
    • Archives of design research
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    • v.15 no.4
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    • pp.369-378
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    • 2002
  • The washing and cleaning the clothing has been considered one of the hardest task of house chores to house wife. It is still big drudgery of house keeping in the so-called high tech society. General statistics says the efforts for better washing condition has developed in minimal. It is hard task as it was before. This study is focusing the appliances for the labor reduction have developed favorably to work more effectively. In the context of home mechanization, it is very important to explore the process of the invent, development and design of washing machine. Another point of view for the washing machine is that it is one of the household artifacts, and we witness a specific character by analyzing how it was evolved. Research shows the invention, innovation, improvement and modification of the washing machine by areas and companies such as Miele and Maytag, where present established washing machine manufacturers around on Europe and USA.

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Reduction effects of isoprothiolane during rice washing and cooking (쌀 세척 및 취반 방법에 따른 isoprothiolane의 감소 효과)

  • Myungheon Kim;Mihyun Cho;So Eun An;Moo-Hyeog Im
    • Food Science and Preservation
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    • v.30 no.3
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    • pp.472-482
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    • 2023
  • This study used gas chromatography combined with the microelectron capture detection method to determine the most effective washing and cooking methods for removing isoprothiolane from rice. The initial isoprothiolane concentrations in brown and polished rice, before washing, were 17.03 mg/kg and 1.67 mg/kg, respectively. Residual concentrations declined with more washing cycles (19.3-59.3% for brown rice; 43.1-66.5% for polished rice); and by increasing the temperature of the washing water from 5℃ to 40℃ (56.6-63.1% for brown rice; 67.1-74.9% for polished rice). Hand-washing samples using gentle stirring or harsh rubbing reduced pesticide concentrations by 63.1-71.6% for brown rice, versus 75.4-87.4% for polished rice. Reduction in isoprothiolane concentrations varied based on the rice cooker type and whether the rice was pre-soaked. Immediate cooking using an electric- or pressure-cooker showed 78.5% and 78.4% reduction in brown rice, compared with 94.0% and 94.0% for polished rice, respectively. Pre-cooking immersion for 30 min showed similar reductions of 83.4% and 83.4% in brown rice, versus 95.8% and 95.8% in polished rice. The results of this study suggest that the most effective method for removing residual isoprothiolane from both brown rice and polished rice was to wash six times (with vigorous rubbing during the 2nd and 3rd washing) in 7-fold water at 40℃, followed by immersion for 30 min before cooking. Regardless of the type of rice cooker, heating is sufficient to remove an average of 83.4% and 95.8% of isoprothiolane from brown rice and polished rice, respectively.

A Study on the Hand Hygiene of Food Handlers of Food Court and Cafeteria in University Campus (대학 구내 휴게음식점 종사자의 손 위생관리에 관한 연구)

  • Kim, Jong-Gyu;Park, Jeong-Yeong;Kim, Joong-Soon
    • Journal of Food Hygiene and Safety
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    • v.25 no.2
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    • pp.133-142
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    • 2010
  • This study was performed to investigate awareness of hand washing, hand washing behavior, and the levels of indicator microorganisms on hands of food handlers who work in the food court and cafeteria of a university campus. The three methods used were questionnaire survey by interview, direct observation in restrooms, and microbiological examination according to the Food Code of Korea. A positive attitude toward hand washing compliance was reported by the responded food handlers; however, improper hand washing and poor hand hygiene of the food handlers were recognized by the unnoticed direct observation. Significant differences were found between the questionnaire survey and the direct observation (p < 0.05) in hand washing compliance after using the toilet, duration of hand washing, use of hand washing agent, washing different parts of the hands, hand-drying method, temperature of water, and method of turning off the water. Samples taken from their hands before work showed higher level of standard plate count, total and fecal coliforms, and Escherichia coli than those taken after washing with water. After washing hands with antiseptic liquid soap, the bacterial populations including Staphylococcus aureus on hands were dramatically reduced. This study indicates that there is a remarkable difference between the food handlers' awareness of hand washing and their hand washing behavior. Poor hand washing compliance and hand hygiene were indicated by the positive results of total and fecal coliforms, E. coli, and S. aureus on hands of some food handlers. The findings of this study suggest that the hand hygiene of the food handlers need to be improved. More training/education on hand washing and hand hygiene of the food handlers should be necessary.

Effect of Spinal Cord Removal before or after Splitting and Washing on CNST Decontamination of Beef Carcasses

  • Lim, D.G.;Kim, D.H.;Lee, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.11
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    • pp.1770-1776
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    • 2007
  • Beef carcasses were examined to explore the effects of spinal cord removal and washing on central nervous system tissue (CNST) decontamination of the surface during the slaughtering process. A total of 15 carcasses were split by sawing centrally down the vertebral column and left sides of split carcasses were used for analysis. Samples were collected by swabbing the surface from 4 defined parts on the interior and 4 on the exterior of carcasses from the abattoir and analyzed using an ELISA-based test. The results showed that automatic and manual spray washing decreased CNST contamination, especially on the interior ventral parts of carcass surfaces (p<0.01), but did not decrease CNST on the interior dorsal parts. Increasing washing time to 60 s did not affect the reduction of CNST contamination. Samples following spinal cord removal prior to splitting showed lower calculated levels of "risk material" than the stated limit of detection (0.1%) of the ELISA kit on interior and exterior carcass parts (p<0.01). Therefore, spinal cord removal prior to splitting could be a very effective way to minimize CNST contamination of beef carcasses.

VOCs Reduction of Visible-light Responsive Photocatalyst coated nylon/polyester composite fiber for Vehicle Interior Parts and Materials (가시광 감응형 광촉매가 코팅처리된 자동차내장재용 Nylon/Polyester 복합섬유의 VOCs 저감)

  • Choi, Sei-Young
    • Elastomers and Composites
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    • v.49 no.1
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    • pp.53-58
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    • 2014
  • In this study, characteristics of visible-light responsive photocatalyst Weltouch, especially VOCs reduction of visible-light responsive photocatalyst coated nylon/polyester composite fiber for vehicle interior parts and materials were evaluated. Visible-light responsive photocatalyst Weltouch was observed for both anatase phase and rutile phase. It is activated by light longer than 420nm. VOCs and formaldehyde generated from visible-light responsive photocatalyst treated nylon/polyester composite fiber were reduced confirmly. Visible-light responsive photocatalyst was firmly attached to the surface of nylon/polyester composite fiber without elimination even after 25 times repeated washing. And washing durability of nylon/polyester composite fiber confirmed the excellence that reduction effects of VOCs after repeated washing has appeared as much as before washing.