• 대한소아치과학회지
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• 제34권4호
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• pp.590-598
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• 2007

유아용 시럽형 약물은 어린이가 쉽게 복용할 수 있도록 여러 종류의 당분을 감미제로 사용하고 있으며 그로 인한 우식의 위험이 높다고 할 수 있다. 그러나 시럽형 약물의 우식유발성에 대한 보호자의 인지도는 매우 낮으며 의료 종사자들 조차 이를 소홀히 여기고 있어 문제의 심각성이 크다고 할 수 있다. 본 연구는 시럽형 약물이 구강 내 산도에 미치는 영향에 대하여 조사할 목적으로, 15 종의 시럽형 약물의 산도를 조사하고, 그 중 널리 시판되는 4종을 선택하여 이 약물들이 치태의 산도 변화에 미치는 영향을 평가하였다. 또한 가장 흔하게 사용하는 유아용 시럽형 약물의 일종인 코푸시럽의 복용방법에 따른 타액의 산도 변화를 측정하여 다음과 같은 결과를 얻었다. 1. 15 종 시럽형 약물의 산도는 pH $3.0{\sim}6.8$의 범위에서 다양하여 평균 pH $4.7{\pm}0.94$로 나타났다. 2. 치태의 산도변화를 측정하기 위해 선정된 4종의 시럽형 약물 모두는 구강 내 투입 직 후 법랑질의 탈회 임계점인 pH 5.5 이하로 치태의 산도를 급격히 떨어뜨렸으며, 시간 경과에 따른 치태의 산도 변화에서 콜디(종합 감기약)를 제외한 모든 약물에서는 유의한 차이가 없었다(p>0.05). 3. 코푸 시럽으로 구강을 헹구어낸 경우와 코푸 시럽에 이어 물로 구강을 헹구어낸 경우 타액의 산도 변화에 있어서는 유의한 차이가 있었다(p<0.05).

• 한국염색가공학회지
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• 제8권6호
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• pp.73-80
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• 1996

수세에 대한 관심이 매우 높아지면서 습윤공정에서 용수사용량을 절감시키는 수세기술과 저장력 주행에 의한 고효율 수세기술이 염색공업 전반에서 절실히 느껴지고 있는 것은 감안할 때, 최근 국내에서 개발된 수세기가 높은 수세효율성과 저장력 주행, 에너지절감을 위해 어떠한 구조적 특정을 가지고 있는지 살펴보고자 한다.

• 복식문화연구
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• 제21권6호
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• pp.950-960
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• 2013

The purpose of this research is to provide accurate information of household washers and detergents for consumers, so that help the producers who make washing machine and detergent to get basic material and also help consumers to choose washing machine. Experiment was proceed with two type of washers to compare energy consumption, washing performance, rinsing effectiveness further, damage caused by entanglement of laundry and fabric was assessed. Detergent P and T were used to compare the performance related to differences of ingredients of detergent. Soiled fabrics of EMPA 108 set were used to evaluate performance of washing by different types of contamination. A summary of experimental results are : First, for the consumption of water, drum-type washer consumed 53% less than pulsator-type washer. On the other hand, the washing time was almost similar for both these machines, but pulsator-type washer showed shorter progress, implying that power saving was more efficient in this case. Second, the drum-type washer showed better performance for contamination with all types of detergent, but the pulsator-type washer showed better rinsing performance. Third, the drum-type washer performed less data of tangle level and fabric damage. Fourth, detergent "P" exhibited better washing performance than did detergent "T", regardless of the type of soil. And with no limit of detergent variety, water-soluble protein soil showed high removal rate, liposoluble soil especially pigment was hardly removed.

• Restorative Dentistry and Endodontics
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• 제37권1호
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• pp.9-15
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• 2012

Objectives: This study evaluated the effect of 2% chlorhexidine digluconate (CHX) with different application times on microtensile bonds strength (MTBS) to dentin in class I cavities and intended to search for ideal application time for a simplified bonding protocol. Materials and Methods: Flat dentinal surfaces with class I cavities ($4mm{\times}4mm{\times}2mm$) in 40 molar teeth were bonded with etch-and-rinse adhesive system, Adper Single Bond 2 (3M ESPE) after: (1) etching only as a control group; (2) etching + CHX 5 sec + rinsing; (3) etching + CHX 15 sec + rinsing; (4) etching + CHX 30 sec + rinsing; and (5) etching + CHX 60 sec + rinsing. Resin composite was builtup with Z-250 (3M ESPE) using a bulk method and polymerized for 40 sec. For each condition, half of the specimens were immediately submitted to MTBS test and the rest of them were assigned to thermocycling of 10,000 cycles between $5^{\circ}C$ and $55^{\circ}C$ before testing. The data were analyzed using two-way ANOVA, at a significance level of 95%. Results: There was no significant difference in bond strength between CHX pretreated group and control group at the immediate testing period. After thermocycling, all groups showed reduced bond strength irrespective of the CHX use. However, groups treated with CHX maintained significantly higher MTBS than control group (p < 0.05). In addition, CHX application time did not have any significant influence on the bond strength among groups treated with CHX. Conclusion: Application of 2% CHX for a short time period (5 sec) after etching with 37% phosphoric acid may be sufficient to preserve dentin bond strength.

• Journal of Microbiology and Biotechnology
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• 제17권12호
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• pp.1965-1969
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• 2007

Triamino ${\alpha}$-cyclodextrin (CD) was synthesized and the inclusion complex with Minoxidil (MXD) was prepared. ${\alpha}$-CD was azidated by modifying the 6-hydroxylmethyl CD rim with sodium azide. Then, mono-, di-, tri-, and tetra-azidocyclodextrins were separated by a flash column chromatography and reduced to the corresponding amines by hydrogenation with Pd/C. The substantivities of MXD included in either 2-hydroxypropyl ${\alpha}$-CD (HP ${\alpha}$-CD) or triamino ${\alpha}$-CD were evaluated in vitro using hairless mice skins. After applying the preparations onto the skin and rinsing it, the amount of the drug left on the skin was determined using high-performance liquid chromatography (HPLC). It was the highest when the drug was included in triamino ${\alpha}$-CD. The electrostatic interaction between the protonated amino CD and the negatively charged skin would be responsible for the relatively high substantivity. The in vivo hair growth promotion effect of each preparation was investigated, where the sample application onto the clipped backs of female mice (C57BL6) and the subsequent rinsing of the backs were done once a day for 30 days. Only MXD in triamino ${\alpha}$-CD had hair growth promotion effect, possibly due to the significant substantivity.

• 대한치과교정학회지
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• 제24권1호
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• pp.181-192
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• 1994

The effect of topical application on the number of S. mutans was tested in a group of 44 orthodontic patients (mean age, 12Y 3M). They were divided into 5 groups according to the method using NaF and $SnF_2$. The number of S. mutans CFU were counted in stimulated saliva of each subject at baseline, and after one, two, three, and eight weeks. The following results were obtained. 1. In NaF rinsing group, and NaF topical application and NaF rinsing group, the number of S. mutans per ml saliva was not significantly changed. 2. In $SnF_2$ topical application group, and $SnF_2$ topical and NaF rinsing group, the number of S. mutans per ml saliva was significantly reduced. 3. After 8 weeks, there were no significant reduction of the number of S. mutans in comparison with baseline.

• 패션비즈니스
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• 제9권3호
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• pp.114-124
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• 2005

Based on the previous study, three types at synthetic fibers comprising nylon, PET, and acrylic fibers were investigated in this study. The effect at mordanting on the air-permeability and dyeing properties at fabrics was investigated. The effect at rinsing process on the air-permeability and color was quantitatively investigated by rinsing the mordanted fabric specimens 1$\sim$3 times after mordanting. The air-permeability changed peculiarly according to the characteristics of the tiber materials after mordanting. The air-permeability values of nylon and acrylic fabric specimens dropped significantly after mordanting. On the other hand, those of PET fabric specimens hardly changed after mordanting. The metal ions absorbed on the fibers of nylon and acrylic fabrics did not show the mordanting effect. Regardless of mordanting, cochineal dyestuff made direct links with the molecular chains in nylon fabrics exhibiting dark colors. After dyeing acrylic fabrics, the color did not develop at all, even though partial components of the cochineal dyestuff were absorbed apparently.

• 한국산업정보학회논문지
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• 제9권4호
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• pp.8-15
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• 2004

금속의 표면이나 비금속표면에 다른 금속을 사용하여 피막을 만드는 도금 공정은 산과 알칼리를 사용함에 따라 세척 작업으로서 수소 이온 농도(H+)와 수산이온농도(OH+)를 제어하게 된다 따라서, 본 연구에서는 세척수 투입에 따른 수소 이온 농도(H+)와 수산이온농도 (OH+)를 제어하기 위한 여러 가지 제어 기법을 적용하여 최적의 제어기를 설계하고자 하였으며, 이 결과는 세척수를 효율적으로 투입하여 귀중한 수자원을 절약하고, 산과 알칼리의 일정제어로 인하여 제품의 균등한 생산이 가능할 뿐만 아니라 생산 단가를 낮추어 경쟁력에 기여할 것으로 사료된다. 특히, 개발하고자하는 기법은 수학적 모델을 구하기 어려운 공정에서도 적용이 가능하도록 설계하고자 하였으며, 제어 대상의 변화에도 다른 제어 방법 보다 쉽게 알고리즘을 변화시킬 수 있다는 장점이 있도록 하였다.

• 한국환경과학회지
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• 제25권6호
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• pp.817-827
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• 2016

The resistance in series model has been frequently used for determination of various filtration resistance to correctly understand the membrane fouling behaviour in MBR (membrane bio-reactor) for wastewater treatment. The cake layer resistance ($R_c$) which is commonly determined by calculation of flux dataset that are obtained empirically before and after removing the cake layer on membrane surface. However, the calculated Rc values are very dependent on the cleaning methods adapted for removal of cake layer. This study investigated how the various cleaning options affect $R_c$. Seven different cleaning methods were employed: i) ultrasonication (100 W, 10 min), ii) ultrasonication (200 W, 60 min), iii) ultrasonication (400 W, 120 min), iv) water rinsing in a shaker (100 rpm, 10 min), v) water rinsing in a shaker (300 rpm, 60 min), vi) water rinsing, vii) sponge scrubbing. For the hydrophilic PES membrane, the cake layer removal efficiencies ranged from 64% to 10%, indicating that the removal of cake layer was highly dependent on the cleaning options. For the hydrophobic PVDF membrane, the cake layer removal efficiencies ranged from 79% to 97%. Consequently, a standardized method for cake layer removal to determine cake resistance ($R_c$) is needed for correct interpretation of the fouling phenomena.

• 방사성폐기물학회지
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• 제19권2호
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• pp.271-278
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• 2021

In this study, a chlorination technique for recycling Li₂ZrO₃, a reaction product of ZrO₂-assisted rinsing process, was investigated to minimize the generation of secondary radioactive pyroprocessing waste. It was found that the reaction temperature was a key parameter that determined the reaction rate and maximum conversion ratio. In the temperature range of 400-600℃, an increase in the reaction temperature resulted in a profound increase in the reaction rate. Hence, according to the experimental results, a reaction temperature of at least 450℃ was proposed to ensure a Li₂ZrO₃ conversion ratio that exceeded 80% within 8 h of the reaction time. The activation energy was found to be 102 ± 2 kJ·mol^-1·K^-1 between 450 and 500℃. The formation of LiCl and ZrO₂ as reaction products was confirmed by X-ray diffraction analysis. The experimental results obtained at various total flow rates revealed that the overall reaction rate depends on the Cl₂ mass transfer rate in the experimental condition. The results of this study prove that the chlorination technique provides a solution to minimize the amount of radioactive waste generated during the ZrO₂-assisted rinsing process.