• Bulletin of the Korean Chemical Society
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• 제8권3호
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• pp.162-165
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• 1987

The reduction rate of borohydride exchange resin (BER) was greatly enhanced in the presence of lithium salts. Thus 2-heptanone was reduced completely with BER-LiCl in 1 h at room temperature. However, no reduction was observed with BER alone under the same conditions. With this system, organic compounds containing various fuctional groups were examined in ethanol at room temperature. This study revealed that BER-LiCl system exhibits an excellent chemoselectivity for carbonyl group in the presence of other functional groups. Keto esters and epoxy ketones were reduced with BER-LiCl to give the corresponding hydroxy esters and epoxy alcohols with excellent yields. Selective reductions of carbonyl groups were also possible in the presence of other organic compounds containing functional groups such as 1-idooctane, 1-bromooctane, caproamide, hexanenitrile, nitrobenzene, n-butyl disulfide, dimethyl sulfoxide and 1-dodecene.

• 대한기계학회논문집B
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• 제31권1호
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• pp.99-108
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• 2007

In this study, the NOx formation characteristics of one-dimensional $CH_4$/Air premixed flame using detailed-kinetic chemistry are examined numerically. The combustor length and the amount of heat loss are varied to investigate the effect of residence time and heat loss on the NOx formation in a post-flame region. In the flame region, NO is mainly produced by the Prompt NO mechanism including $N_2$O-intermediate NO mechanism over all equivalence ratios. However, thermal NO mechanism is more important than Prompt NO mechanism in the post-flame region. In the case of adiabatic condition, the increase of combustor length causes the remarkable increase of NO emission at the exit due to the increase of residence time. On the other hand, NO reaches the equilibrium state in the vicinity of flame region, considering radiation and conduction heat losses. Furthermore the NO, in the case of $\phi$=1.2, is gradually reduced in the downstream region as the heat loss is increased. From these results, it can be concluded that the controls of residence time and heat loss in a combustor should be recognized as an important NOx reduction technology.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.131.2-132
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• 2000

No Abstract, See Full Text

• 한국응용곤충학회지
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• 제12권3호
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• pp.115-120
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• 1973

본 실험은 침투성살충제 Fussol, Dimethoate, Metasystox 및 Dimecron을 벼, 보리 및 콩씨에 분의처리하였을 때 발아에 미치는 영향과 살충효과 및 그의 지속성을 알기 위해 실시하여 아래와 같은 결과를 얻었다. 1). 법씨는 Fussol처리에서 발아력을 완전히 잃었으며 Dimethoate 처이에서는 처리후 파종시까지 시간이 경과함에 따라 발아율이 크게 저하되었으나 Metasystox 와 Dimecron 처리에서는 발아저해가 비교적 적었다. 2) 보리씨는 Fussol처리에서 처리 후 1일 파종에서는 비교적 발아율이 높았으나 25일 파종에서는 발아력이 완전히 상실되었다. 그밖에 공시약제도 무처리에 비하여 약간의 발아저해가 있었으나 저장기문이 지나도 별로 발아력이 저하되지 않았다. 3) 콩씨에서는 처리후 1일 파종에서 공시약제 모두 비교적 좋은 발아율을 보였으나 Fussol, Dimethoate 및 Metasystox는 처리후 25일 파종에서 발아에 저해가 컸고 Dimecron 처리에서는 발아저해가 비교적 적었다. 4) 볍씨 처리에서 Dimethoate는 파종후 20일까지 끝동매미충에 대하여 살충력이 좋았으나 30일 에서의 살충력은 낮았다. 그밖에 약제처리에서는 살충력이 모두 낮았다. 5) 보리씨 처리에서 Dimethoate는 옥수수테두리진딧물에 대하여 비교적 살충효과가 좋았으나 다른 약제처리효과는 낮았다. 주당 평균 산난수는 무처리 13개에 대하여 Dimethoate 2개, Fussol 4개, Metasystox 6개, Dimecron 7개이었다. 6) 콩씨 처리에서는 파종후 9일까지 공시약제 모두 좋은 살충효과를 나타내었으며 18일 조사에서는 Dimethoate, Metasystox 및 Dimecron에서 비교적 중은 살충효과를 보였으나 Fussol만은 살충력이 무처리와 차리가 없었다. 7) 침투성살충제의 분의처리에 있어서 발아저해와 살충력 및 그의 지속기간은 약제의 종류, 종자의 종류, 처리후 파종시까지의 경과일수에 따라 큰 차이가 있는 것으로 본다.

• 대한두개안면성형외과학회지
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• 제11권2호
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• pp.77-84
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• 2010

Purpose: The nasal bones are the most common fracture sites of the facial bones, and a careful reduction may still result in secondary deformities, such as saddle nose, deviated nose, hump nose etc, requiring secondary cosmetic rhinoplasty. Therefore, this study examined the clinical characteristics of nasal bone fractures to propose guidelines for patient selection and surgical procedures to achieve more satisfactory results and to prevent secondary deformities with simultaneous augmentation rhinoplasty and bony reduction. Methods: The study was based on 26 out of 149 nasal bone fracture patients who underwent simultaneous augmentation rhinoplasty with bony reduction between May 2008 and April 2009. Retrospective analysis was performed according to the clinical data, surgical techniques and postoperative results. Results: Of the 26 patients, there were 15 males and 11 females. The incidence according to the Stranc's classification revealed that 62% of patients were injured by a frontal impact and 38% by a lateral impact. Frontal impact plane I (50%) was the most frequent type. At the follow up, 18 (81.2%) out of 22 patients were satisfied with their postoperative outcome, and the remaining 4 patients were fair. No one was dissatisfied. However, 5 cases in 3 patients (23%) had some complications; minimal implant deviation in 2 cases, minor irregularity on the nasal dorsum in 2 cases and palpable implant movement under palpation in 1 case. None of these cases required surgical correction. Conclusion: With the proper guidance, simultaneous augmentation rhinoplasty with bony reduction can prevent secondary deformities and satisfy the cosmetic outcomes.

• 한국의류산업학회지
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• 제13권2호
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• pp.263-268
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• 2011

One-step reduction/dyeing method was applied for ramie dyeing with natural indigo powder. The effect of reduction/dyeing conditions including the pH of bath, dye temperature and time, and concentration of indigo powder and reduction agent on dye uptake and color properties were investigated. Regardless of addition of alkali, the dyed fabrics appeared in the PB Munsell color range(${\lambda}_{max}$: 660 nm) and the dye uptake was much higher with no addition of sodium hydroxide. Dyeing was carried out through the use of only sodium hydrosulfite in the bath. The maximum dye uptake was obtained at 60 for 30min. Saturated dye uptake was obtained at 2 g/L of sodium hydrosulfite concentration up to 2 g/ L of indigo powder. Whereas, at higher indigo powder concentration (4 g/L), more than 3 g/L of reducing agent concentration was required for obtaining the saturated dye uptake. Color reproducibility was reliable with color difference in the range of 0.03~0.16. Regardless of color strength, fastness to rubbing was acceptable with a 3/4~4/5. Fastness to washing, dry cleaning, and light of samples with low color strength were poor. Whereas, fastness to washing, dry cleaning, and light of samples with high color strength were very good.

• Advances in Traditional Medicine
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• 제2권2호
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• pp.119-124
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• 2002

Cigarette smoking contributes to lung cancer, cardiovascular diseases, oral diseases, etc. In desire to reduce their risk of disease, many cigarette smokers have tried to quit smoking. Sensory aspects of cigarette smoke are important for providing smoking satisfaction. Previously it was reported that citric acid aerosol significantly reduced craving for cigarettes and enhances smoking reduction and cessation. In this study, we tested whether a newly combined product Ciga-X, an aerosol for cessation aid, had toxicity in human embryonic lung fibroblast (MRC-9). The inhibitory effect of Ciga-X on cytotoxicity induced by cigarette smoke extract (CSE) or nicotine was examined in MRC-9, and craving for cigarettes and smorkers satisfaction after using Ciga-X was estimated. Ciga-X did not affect cell viability and had no toxicity in MRC-9. Ciga-X significantly inhibited not only CSE-induced cytotoxicity but also nicotine-induced cytotoxicity in MRC-9. One hundred and forty smokers rated the satisfaction for Ciga-X aerosol and craving reduction for cigarettes after using Ciga-X. The percentage of over 5 rating was 71.0% and 50.0% of subjects in satisfaction test for Ciga-X compared to their own brand and in craving reduction for cigarette, respectively. Besides, craving reduction for cigarette was highly correlated with the duration of smoking. Subjects have smoked under 10 years were more reduced in craving for cigarettes after using Ciga-X as compared to over 10 years (p=0.049). These results suggest that Ciga-X may be effective in promoting smoking abstinence with the reduction of CSE- or nicotine-induced human lung fibroblasts cytotoxicity.

• 대한치과보철학회지
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• 제43권1호
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• pp.30-40
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• 2005

Purpose. The purpose of this study was to compare the fracture strength of the IPS Empress ceramic crown according to the incisal reduction (2.0mm, 2.5mm, 3.0mm) and axial inclination ($4^{\circ}$, $8^{\circ}$, $12^{\circ}$) of the upper canine. Material and methods. After 10 metal dies were made for each group, the IPS Empress ceramic crowns were fabricated and each crown was cemented on each metal die with resin cement. The cemented crowns mounted on the testing jig were inclined 30 degrees and the universal testing machine was used to measure the fracture strength. Results. 1. The fracture strength of the ceramic crown with 3.0mm depth and $12^{\circ}$ inclination was the highest (839N) Crowns of 2.0mm depth and $12^{\circ}$ inclination had the lowest strength (559N). 2. There was no significant difference in the fracture strength by axial inclination in the same incisal reduction group. 3. The fracture mode of the crowns was similar. Most of fracture lines began at the loading area and extended through proximal surface perpendicular to the margin irrespective of incisal reduction.

• Korean Chemical Engineering Research
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• 제48권4호
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• pp.540-543
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• 2010

가스 중에 포함되어 있는 질소산화물을 안전하게 처리하기 위하여 저온 플라즈마 반응기를 제작하여 반응기내에 공급되는 반응물질의 유량과 방전주입전력량에 대한 장치의 특성을 실험적으로 조사하고, 유효성을 검정하였다. 반응가스는 $NO/N_2$ 혼합가스와 $N_2/O_2$ 혼합가스를 이용하여 초기 NO 농도를 설정하고, 유속을 1~4 l/min으로 공급하였다. 반응물질의 유량이 증가할 때 NO의 감소율이 낮고, 방전주입전력이 높을 때 NO의 분해가 용이하였다. 또한 반응물질의 지연시간이 길고 방전주입전력이 높을수록 NO의 분해에너지 효율이 높았으며, 유량이 많고 방전 주입 전력량이 증가할수록 오존의 생성량이 증가하였다.

• 방사성폐기물학회지
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• 제13권3호
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• pp.229-233
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• 2015

파이로프로세싱 전해환원 공정에서 현재 사용 중인 Pt 양극을 대체하기 위한 소재 개발은 매우 중요하다. 이 연구에서는 전기화학 반응시 산소를 발생시키는 전도성 세라믹 양극으로서 TiN의 전기화학적 거동을 알아보았다. UO₂의 전해환원이 일어나는 동안 TiN 양극의 적합성과 안정성에 대한 평가를 진행하였다. LiCl-Li₂O 용융염에서 TiN 양극을 이용하여 UO₂를 전기화학적으로 금속 U로 변환시킬 수 있었다. 반응 도중 TiN의 산화 반응은 관찰되지 않았다. 하지만 TiN 내부에서 공공이 생기는 것을 확인하였으며, 이에 따라 소재 수명에 제한이 있을 것으로 판단된다.