• 한국응용과학기술학회지
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• 제28권2호
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• pp.178-184
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• 2011

The analysis of reaction kinetics provided that the reaction order was the $1^{st}$ of triglyceride and the rate constant was 0.067 $min^{-1}$. The transesterification of camelina oil using 0.6 wt% mixed catalyst which consists of 40 v/v% of potassium hydroxide (1 wt%) and 60 v/v% of tetra methyl ammonium hydroxide (0.8 wt%), was carried out at $65^{\circ}C$ on the tubular reactor packed with static mixer. The conversion was shown to be 95.5% at the 6:1 molar ratio of methanol to oil, flow rate of feed of 3.0 mL/min and 24 of element of static mixer. The volume of washing water emitted by 0.6 wt% mixed catalyst was the half of the volume emitted by 1 wt% potassium hydroxide.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.53-54
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• 2015

This study is conducted to investigate the characteristics of cracks depending on the different mixture rates of calcium hydroxide and distilled water in high-strength concrete, which is substituted with a high percentage of blast-furnace slag, by using specimens produced under different heating temperatures: 600℃, 800℃, and 1000℃, respectively. According to the results of the study, the specimen heated under the temperature of 600℃ did not produce cracks; the specimen heated under 800℃ produced little cracks and showed no difference between calcium hydroxide and distilled water; whereas the specimen heated under 1000℃ produced cracks larger than 5mm on average in the case of calcium hydroxide, compared to distilled water.

• 한국염색가공학회지
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• 제8권3호
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• pp.31-35
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• 1996

Modal fabric was pretreated with sodium hydroxide, sodium persulfate, and their combined mixture by pad-steaming procedure. The tearing strength of the pretreated modal fabric was measured for subsequent microfibrillation. The solubility of modal fiber in sodium hydroxide solution was highest at 10 % concentration of sodium hydroxide. Extended steaming of the modal fabric padded with 6% sodium hydroxide solution did not reduce the tearing strength appreciably. 2% sodium persulfate pretreatment greatly reduced the tearing strength of modal fabric within 7 minutes of steaming time. The pretreatment with combined composition of sodium hydroxide and sodium persulfate brought about stable reduction in tearing strength within 1 minute of steaming time, which would be appricable to the continuous pretreatment of modal fabric for microfibrillation. Microfibrillation behavior of the pretreated modal fabric was tested also.

• 식물병과 농업
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• 제5권2호
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• pp.95-99
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• 1999

Chemical control of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae was attempted by spraying of streptomycin sulfate ·oxytetracycline WP streptomycin WP streptomycin ·copper hydroxide WP kasugamycin SL kasugamycin·copper oxychloride WP and copper hydroxide WP. The control efficacies of the bactericides were variable depending upon the spraying schedule,. Application of streptomycin WP and streptomycin sulfate·oxytetracycline WP from middle April to early May was found to be the most effective in controlling the bacterial canker. For copper hydroxide WP the spraying from middle January to early February showed the highest control efficacy. Kasugamycin SL was the most effective in controlling the disease by spraying from middle April to early May but it was still relatibvely effective during other spray periods. Foliar application of copper hydroxide WP and copper-antibiotic formulaions after middle April caused severe phytotoxicity. Kasgamycil SL streptomycin WP streptomycin·copper hydroxide WP and copper hydroxide WP were potential bactericides which could substitute streptomycin sulfate·oxytetracycline WP. Selective applications of the bactericides according to their optimum spray time can enhance the control efficacies against bacterial canker of kiwifruit and retard the emergency of resistant strains of P. syringae pv. actinidiae to the bactericides. The optimum spray number of streptomycin sulfate·oxytetracycline WP was 3 times with 15-day-intervals or 4 times with 10-day-intervals. The result suggested that the potential bactericides to bacterial canker of kiwifruit should be also used according to their optimum spray schedules in order to get their highest control efficacies.

• 한국치위생학회지
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• 제18권4호
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• pp.423-432
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• 2018

Objectives: Calcium hydroxide, a root canal temporary sealer, has long been used and it has anti-bacterial and anti-inflammatory activity. To investigate the properties of a newly developed calcium hydroxide paste comprising silicon-substituted hydroxyapatite (Si-HA), we examined the anti-inflammatory activity of the new calcium hydroxide paste in RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS), which causes infection of the root canal. Methods: The test materials, including Calcipex II as control group and the newly developed TRC paste, were extracted from cell culture media and then diluted for experiment. In LPS-stimulated RAW 264.7 cells, the cytotoxicity and nitric oxide (NO) production of test materials were measured by MTT assay and Griess reagents, respectively. Also, the expression of the inducible nitric oxide synthase (iNOS) was assessed by western blotting. Results: The IC50 values of Calcipex II and TRC paste were $17.6mg/m{\ell}$ and $13.5mg/m{\ell}$, respectively. The level of NO, increased by LPS, was dose-dependently inhibited more by TRC paste than Calcipex II treatment. In addition, iNOS expression was decreased by 71% and 92% at concentrations of $2mg/m{\ell}$ and $20mg/m{\ell}$ of TRC paste, respectively. Conclusions: We demonstrated that the Si-HA calcium hydroxide paste has a slightly improved anti-inflammatory property and further studies are needed before clinical recommendations are proposed.

• 자원리싸이클링
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• 제13권2호
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• pp.47-53
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• 2004

알루미늄 폐드로스는 알루미늄 용해업체에서 발생되는 주요 폐기물 중 하나인데, 폐드로스에는 상당량의 금속 알루미늄이 잔류한다. 본 연구에서는 알루미늄 폐드로스 내에 잔류하는 금속 알루미늄을 회수하고자 폐드로스를 수산화나트륨 용액으로 침출하여 폐드로스 중의 잔류 알루미늄을 용액 상으로 침출, 분리시킨 다음. 침출용액 중에서 알루미늄 성분을 수산화알루미늄으로 제조하는 연구를 수행하였으며, 연구결과의 상용화를 위하여 시범생산라인을 건설하여 시운전하였다. 시범생산라인은 년간 1,000톤의 폐드로스를 처리하여 500톤의 수산화알루미늄을 생산할 수 있는 규모이다. 생산라인의 시운전 결과 연구 개발한 기술의 상용화 가능성을 확인할 수 있었으며, 시험생산한 수산화알루미늄은 수처리 응집제용으로 사용 가능하다고 판단된다.

• 구강회복응용과학지
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• 제37권2호
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• pp.95-100
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• 2021

수산화칼슘제재는 근관치료 과정 동안 근관 내 첩약제로서 널리 사용되고 있다. 이번 증례 보고에서는 근관 세척제로 사용된 수산화칼슘제재가 치근단 병소로 의도치 않게 과충전된 치아에 대해 정확한 진단과 적절하게 행해진 비외과적인 재근관치료를 통해 성공적으로 치료한 증례를 보고하고자 한다. 과충전된 수산화칼슘제재가 치근단 병소의 치유 과정에 영향을 줄 수 있으므로 수산화칼슘제재의 과충전이 발생하지 않도록 주의를 기울여야 한다.

• 자원리싸이클링
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• 제10권5호
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• pp.8-15
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• 2001

알루미늄드로스는 드로스의 특성과 처리 후 용도를 고려하여 재활용하여야 한다. 본 연구에서는 국내 재생 알루미늄업체에서 발생된 알루미늄드로스를 수산화알루미늄의 원료로 재활용하고자 하였다. 드로스 시료를 크기에 따라 선별하고, $850mu$m 보다 작은 크기의 드로스를 수산화나트륨 용액으로 침출하여 드로스 중의 잔류 알루미늄을 용액 중으로 분리 추출하고, 침출용액에서 석출반응에 의하여 수산화알루미늄 침전물을 회수하였다. 시험 제조한 수산화알루미늄의 순도는 98% 이상이었고, 입경은 $3~39\mu$m 범위였다. 또한, 침출시 드로스의 장입량, NaOH 농도 및 광액농도가 수산화알루미늄의 회수율에 미치는 영향을 조사한 결과 폐드로스를 A/C비 0.5, 광액농도 14~16%로 침출하는 것이 석출시 회수율이 가장 높았다. 본 연구결과를 알루미늄드로스 재활용의 한 가지 방법으로 제안하고자 한다.

• Journal of Pharmaceutical Investigation
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• 제2권1호
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• pp.5-13
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• 1972

There are some repels in which they studied on the change of acid-consuming capacity of aluminium hydroxide resulted from the passing of time. However, the relationship between grain sizes(particle sizes) and the acid-consuming capacity of dried aluminium hydroxide gel was not been studied. And studies on the grain sizes of aluminium hydroxide gel qualified by pharmacopoeia of Korea has not been reported. For the purpose of studying these two problems, the author prepared two-kinds of aluminium hydroxide gel as follows : $Na_2OAl_2O_3+CO_2------{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 1 $Al_2(SO_4)_318H_2O+6NaHCO_3{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 2 Both of sample 1 and 2 are found to be amorphous by X-ray diffraction methods, and their acid-consuming capacities were determined by the method of pharmacopeia of Korea. The grain size was measured by X-ray diffraction method, the particle sizes observed by electron microscopy, and the change of acid-consuming capacity with passing of time was determined by the method of pharmacopoeia of Korea. The results of these studies are summerized as follows: 1. The grain size was linearly enlarged as the time goes by. The aluminium hydroxide gel gradually crystallized in a certain period of time. 2. The acid-consuming capacity was in exponential function, decreased as the grain size of them enlarged. 3. One particle consists of tens of grains.4. Grinding the Sample obtained in any period of testing time in mortar did not change both their grain size and their acid-consuming capacity. 5. The grain size of dried aluminium hydroxide gel ought to be micronized less than $100{\AA}$ for maintaining the ability such as consumes 250m1 of 0. 1N-HC1 solution per Is of $Al(OH)_3$ described in pharmacopoeia of Korea.

• 한국결정성장학회지
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• 제28권2호
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• pp.91-97
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• 2018

Indium hydroxide 분말이 침전법으로 제조되었다. 반응온도($150{\sim}250^{\circ}C$)와 각 반응온도에서의 유지시간(1~72 h)이 실험 변수로 사용되었다. 각각의 제조된 분말을 X-선 회절 분석기(XRD)와 투과전자현미경(FE-TEM), BET를 통해 입자크기, 미세구조 및 결정상을 관찰하였다. 본 연구에서는 침전법에 의해 제조된 Indium hydroxide가 열처리 시 반응온도와 각 반응온도에서의 유지시간에 따라 어떻게 Indium oxide로 상전이 거동을 하는 지를 고찰하였다.