• 한국재료학회지
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• 제18권6호
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• pp.307-312
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• 2008

In this study, a new cleaning process with a low cost of ownership (CoO) was developed with ozonated DI water ($DIO_3$). An ozone concentration of 40 ppm at room temperature was used to remove organic wax film and particles. Wax residues thicker than $200\;{\AA}$ remained after only a commercial dewaxer treatment. A $DIO_3$ treatment in place of a dewaxer showed a low removal rate on a thick wax layer of $8000\;{\AA}$ due to the diffusion-limited reaction of ozone. A dewaxer was combined with a $DIO_3$ rinse to reduce the wax removal time and remove wax residue completely. Replacing DI rinse with the $DIO_3$ rinse resulted in a surface with a contact angle of less than $5^{\circ}$, which indicates no further cleaning steps would be required. The particle removal efficiency (PRE) was further improved by combining a SC-1 cleaning step with the $DIO_3$ rinsing process. A reduction in the process time was obtained by introducing $DIO_3$ cleaning with a dewaxing process.

• 한국콘텐츠학회논문지
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• 제19권11호
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• pp.424-433
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• 2019

본 논문은 설탕물 양치 전후, 타액 내 칼륨과 마그네슘의 농도 변화를 분석한 연구이다. 타액 샘플은 10% 자당(포도당) 용액으로 양치하기 전과 양치 직후부터 60분까지 채취하였고 이온크로마토그래피법으로 분석하였다. 설탕물 양치 전 칼륨의 평균 농도는 274.3±77.9 mg/ℓ (279.2±62.1 mg/ℓ)이며, 마그네슘의 평균 농도는 4.5±2.5 mg/ℓ(4.8±2.0 mg/ℓ)이다. 설탕물 양치 직후, 칼륨과 마그네슘의 농도는 자당의 경우 143.9±55.4 mg/ℓ, 2.7±3.1 mg/ℓ이며, 포도당의 경우 150.9±64.2 mg/ℓ, 2.6±0.7 mg/ℓ로 대조군에 비해 급격히 낮아졌으나, 양치 후 60분에서 대조군의 이온 농도 수준으로 회복됨을 확인하였다. 즉 설탕물 양치 직후에는 자극에 의해 타액 내 칼륨과 마그네슘 이온 농도가 낮아지나, 60분 후에는 타액의 자정작용으로 구강 내 향상성이 회복되었다. 본 논문은 타액에 관한 기초자료를 축적하는 것에 의의를 두고 연구하였다.

• 분석과학
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• 제14권1호
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• pp.21-27
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• 2001

본 실험에서는 유도결합 플라스마 원자방출 분광법 (ICP-AES)에서 perfluoroalkoxy (PFA) nebulizer와 microconcentric nebulizer (MCN)을 이용하여 본 실험실에서 제작된 double membrane desolvator (DMD)의 분석능력을 연구하였다. MCN과 비교하여 PFA nubulizer는 수용액 시료의 경우에는 DMD-ICP-AES에서 비슷한 분석감도를 보였으나, isopropyl alcohol 시료에서는 좀 더 나은 분석감도를 보였다. PFA nebulizer는 여러 가지 산들에 견디기 때문에 HCI, $H_2SO_4$ 뿐만 아니라 HF 용액도 도입하여 분석할 수 있었는데, 모두 2% 미만의 상대표준편차로 분석되었다. 기억효과를 측정한 결과, 신호가 1% 미만으로 감소되는 rinse-out time은 PFA에서는 35초인 반면 MCN은 45초로 얻어졌다.

• The Plant Pathology Journal
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• 제17권1호
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• pp.62-66
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• 2001

Detection of Xanthomonas axonopodis pv. citri (Xac) on citrus fruits for exporting is usually made by bacteriophage test (BPT) to demonstrate the pathogen-free status. BPT has rather time-consuming and complicate procedures for dealing with massive samples to be inspected. In this study, enzyme-linked immunosorbent assay (ELISA) was applied to detect Xac on fruits, and compared with BPT. In ELISA, positive reactions occurred in the bacterial densities of $3\times10^5$ cells/ml or more. To detect the bacterial infection on citrus fruits with a density of lower than $3\times10^5$ cells/ml, the bacterial suspensions were mixed with fruit rinse water and incubated in broth medium. Ordinary peptone sucrose broth (PSB) was not a proper medium for increasing Xac density specifically enough to be detect by ELISA. On the other hand, modified PSB (MPSP) amended with Fe-EDTA (0.25 g/$\ell$) and 2.5% potato-dextrose broth sufficed to differentiate uninfected and infected citrus fruits by ELISA after 24 h incubation of the fruit rinse water. Using various citrus samples from infected and uninfected fields, efficiencies in detecting Xac on fruits were compared between ELISA and BPT. For infected fruits samples, ELISA detected Xac by 100%, while BPT by about 44%, indicating that the detection efficiency was improved by 23.5% by ELISA, compared to BPT. In addition, ELISA has simpler procedures for testing and is less time-consuming than BPT, suggesting that ELISA may be accurate and simple method to detect Xac on citrus fruits.

• 청정기술
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• 제7권4호
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• pp.225-242
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• 2001

산업체에서 부품을 가공하거나 완성품을 제조하는 과정에서 세정 공정은 필수적으로 사용하고 있고 현재 국내외 대부분의 제조업체에서는 오존파괴물질인 CFC-113이나 1,1,1-TCE 대신에 보다 환경친화적인 수계 세정제로의 대체가 진행중이다. 그러나 수계 세정시스템은 세정공정이나 헹굼공정에서 다량의 물을 사용하기 때문에 많은 폐수를 발생시키는 단점이 있다. 따라서 수계 세정시스템에서는 이러한 발생을 최소화하고 세정액과 헹굼수의 성능을 오랫동안 유지시키기 위한 모니터링 기술과 재활용 기술의 도입이 긴요하다. 본고에서는 수계 세정시스템에 사용하는 세정제와 주요 오염물질인 절삭유를 조사 분석하였고 산업현장에서 도입 가능한 수계 세정시스템의 모니터링 기술과 재활용 기술 등을 분석 평가하였다.

• Journal of Animal Science and Technology
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• 제64권3호
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• pp.397-408
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• 2022

Rinse & Chill^® technology (RCT) entails rinsing the vasculature using a chilled isotonic solution (3℃; 98.5% water and a blend of dextrose, maltose, and sodium phosphates) to rinse out the residual blood from the carcass. Infusion of pre-chilled solutions into intact animal carcasses immediately upon exsanguination is advantageous in terms of lowering the internal muscle temperature and accelerating chilling. This technology is primarily used for purposes of effective blood removal, favorable pH decline, and efficient carcass chilling, all of which improve meat quality and safety. Although RCT solution contains some substrates, the pre-rigor muscle is still physiologically active at the time of early postmortem and vascular rinsing. Consequently, these substrates are fully metabolized by the muscle, leaving no detectable residues in meat. The technology has been commercially approved and in continuous use since 2000 in the United States and since 1997 in Australia. As of January 2022, 23 plants have implemented RCT among the 5 countries (Australia, US, Canada, New Zealand, and Japan) that have evaluated and approved RCT. All plants are operating under sound Sanitation Standard Operation Procedures (SSOP) and a sound Hazard Analysis Critical Control Point (HACCP) program. No food safety issues have been reported associated with the use of this technology. RCT has been adapted by the meat industry to improve product safety and meat quality while improving economic performance. Therefore, this review summarizes highlights of how RCT technically works on a variety of animal types (beef, bison, pork, and lamb).

• Restorative Dentistry and Endodontics
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• 제46권1호
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• pp.3.1-3.14
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• 2021

Objectives: This study aimed to evaluate the interface between a calcium silicate cement (CSC), Biodentine and dental adhesives in terms of sealing ability. Materials and Methods: Microleakage test: 160 standardized class II cavities were prepared on 80 extracted human molars. The cavities were filled with Biodentine and then divided into 2 experimental groups according to the time of restoration: composite resin obturation 15 minutes after Biodentine handling (D0); restoration after 7 days (D7). Each group was then divided into 8 subgroups (n = 5) according to the adhesive system used: etch-and-rinse adhesive (Prime & Bond); self-etch adhesive 2 steps (Optibond XTR and Clearfil SE Bond); self-etch adhesive 1 step (Xeno III, G-aenial Bond, and Clearfil Tri-S Bond); and universal used as etch-and-rinse or self-etch (ScotchBond Universal ER or SE). After thermocycling, the teeth were immersed in a silver nitrate solution, stained, longitudinally sectioned, and the Biodentine/adhesive percolation was quantified. Scanning electron microscopic observations: Biodentine/adhesive interfaces were observed. Results: A tendency towards less microleakage was observed when Biodentine was etched (2.47%) and when restorations were done without delay (D0: 4.31%, D7: 6.78%), but this was not significant. The adhesives containing 10-methacryloyloxydecyl dihydrogen phosphate monomer showed the most stable results at both times studied. All Biodentine/adhesive interfaces were homogeneous and regular. Conclusions: The good sealing of the CSC/adhesive interface is not a function of the system adhesive family used or the cement maturation before restoration. Biodentine can be used as a dentine substitute.

• 한국치위생학회지
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• 제19권1호
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• pp.151-159
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• 2019

Objective: This study aimed to investigate the relation between rinsing time and the change in enamel surface after fluoride application on the enamel surface. Methods: We recruited two sample groups with different mouth rinsing times. While one group rinsed the teeth immediately after applying acidulated phosphate fluoride (APF) gel, the other group rinsed the teeth 30 minutes after APF gel application. In each group, we performed the following four-step experiment: (i) apply APF gel on the teeth, (ii) rinse the teeth, (iii) immerse the teeth in orange juice, and (iv) measure enamel surface microhardness and scan enamel surfaces. Results: The group that rinsed 30 minutes after treatment exhibited greater microhardness than the group that rinsed immediately after fluoride treatment. The former also showed smooth and regular crystallization, whereas the latter showed rough and damaged crystallization and irregular surfaces. Conclusions: Based on these observations, we conclude that delaying the rinsing time improves the dental caries preventive effect of fluoride.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.54-58
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• 1994

H$_2$ bake and GeH$_4$ clean are used as a in-situ pre-clean method in low temperature Si based epitaxial growth technology using rapid thermal processing chemical vapor deposition (RTPCVD). In this paper, the H$_2$ bake and GeH$_4$ clean processes are optimized for low surface defect density using Taguchi method. In H$_2$ bake process, the epitaxial growth temperature affects dominantly on the surface defect density, and the next affecting factors are H$_2$ bake temperature and rinse time in de-ionised water. In GeH$_4$ clean process, GeH$_4$ clean temperature affects most strongly on the surface defect density, and the minor factor is GeH$_4$flow rate. The optimum process conditions predicted fly Taguchi method agree well with tile experimental data in both in-situ clean processes.

• 대한소아치과학회지
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• 제26권2호
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• pp.262-274
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• 1999

구강내의 불소농도를 증가시키는 여러 방법에는 불화된 상수도를 섭취하거나 불소보조제를 복용하는 전신적 투여방법과 불소치약, 불소양치액, 불소젤의 도포와 같은 국소적 투여방법이 있다. 그동안 다양한 delivery system을 통한 국소도포용 불소제제가 임상적으로 우식증을 예방하는데 도움이 된다는 사실이 확인되었다. 최근의 연구에서 불소의 항우식효과는 치아주위의 oral fluid environment속에서 불소의 중요성을 지적하고 있다. 비자극성 전타액내 불소농도는 주어진 시간동안 치면과 상호작용이 가능한 aqueous phase의 불소를 나타낸다고 한다. 따라서 타액내의 불소 농도를 조사함으로써 간접적으로 우식예방효과에 대한 정보를 얻을 수 있다. 우식증예방을 위해 환자에게 여러 가지 국소도포방법 중 한 가지를 추천하기에 앞서 이들 각 방법이 타액내 불소농도를 증가시키는데 얼마나 효과적인지 알 필요가 있다. 이에 저자는 국소적 불소도포후 구강내 불소의 잔류량과 시간별 농도를 비교하고자 현재 국내에서 많이 쓰이고 있는 서로다른 네가지 불소제제를 사용하고 난 뒤 시간변화에 따른 타액내 불소농도를 HMDS를 이용한 확산법과 불소이온전극을 사용하여 측정하고 다음과 같은 결과를 얻었다. 1. 비자극성 혼합타액내 평균 불소농도는 $0.0152ppm{\pm}0.0091ppm$이었으며, 비자극성 타액분비율은 0.34-0.36ml/min으로 각군간에 통계적 유의차는 없었다. 2. 불소제제 사용직후를 제외하고는 모든 구간에서 타액내 불소 농도는 APF gel군>neutral gel군>불소양치액군>불소치약군의 순이었고, 불소처치 120분 경과후 불소치약군의 타액내 불소농도가, 180분 경과후 불소양치액군의 불소농도가 대조군과 통계적 유의차를 보이지 않은 반면, 6시간 경과후까지 APF gel군과 neutral gel군의 타액내 불소농도가 대조군에 비해 유의성있게 높게 유지되었다(p<0.05). 3. 불소제제 사용직후부터 120분 경과후까지 타액내 잔류불소량($AUC_{0-120min}$)은 neutral gel군>APF gel군>불소양치액군>불소치약군의 순이었고, neutral gel군과 APF gel군이 대조군과 나머지 두 군에 비해 유의하게 높은 값을 보였다(p<0.05).