• 대한화학회지
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• 제9권2호
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• pp.78-80
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• 1965

The organic yields(i.e., fraction of nuclear events resulting in organic compound formation) of the radioactive neutron capture reactions of the halogens in purified aromatic halides have been determined in the liquid and solid state, in the presence of scavenger, elemental halogen for thermal atoms, and in the presence of oxygen. Among the important results are; (1) organic yields of the halides are due in part to hot processes and in part to thermal processes; (2) temperature (from liquid state to solid state); (3) the organic yield of chlorobenzene is the same in the solid phase as in the liquid phase whereas the yields of the bromo-and iodobenzene are higher in the solid.

• Bulletin of the Korean Chemical Society
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• 제3권3호
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• pp.119-122
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• 1982

Rigid ${\alpha}$-oximino ketones containing two functional groups such as 2-oximino-1-acenaphthenone and 2-oximino-1-indanone were synthesized and the simultaneous reduction of the two functional groups of ${\alpha}$-oximino ketones by $LiAlH_4$ gave the corresponding amino alcohols, 2-amino-1-acenaphthenol and 2-amino-1-indanol. The yields of the reduction products of the ${\alpha}$ -oximino ketones remarkably increased, as the increase of molar ratio of hydride used to the reactant. The use of 24 moles of $LiAlH_4$ was found to afford the best result in the reduction of the rigid ${\alpha}$-oximino ketones to the corresponding amino alcohols. The yields was not affected by the variation of solvents such as ether, THF and diglyme.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2243-2248
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• 2011

Carbon-based solid acid catalyst was found to be highly efficient, eco-friendly and recyclable heterogeneous catalyst for the multicomponent reaction of dimedone, aromatic aldehydes, and a nitrogen source (ammonium acetate or aromatic amines) under solvent-free conditions, giving rise to 1,8-dioxodecahydroacridines in high yields. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.

• 한국식품과학회지
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• 제25권5호
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• pp.589-591
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• 1993

3가지의 다당류 분해효소를 사용한 가수분해가 미역추출액의 상징액율, 고형분 수율, 점도에 미치는 영향을 조사하였다. 그 결과 추출전에 효소분해할 때 고형분 농도를 27.31%, 고형분 수율을 14.04%까지 증가시켰다. 그러나 미역 분산액을 원심분리 후의 상징액율은 약간 낮았다. 추출액의 점도는 효소분해 초기에 유의적으로 증가하였다.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.981-983
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• 2010

The condensation of several aromatic/heteroaromatic aldehydes with 2-aminothiophenol catalyzed by silica sulfuric acid under microwave irradiation afforded 2-arylbenzothiazoles in high yields and short reaction times under solvent-free conditions. The major advantages of the present method are good yields, ecofriendly, reusable catalyst, mild and solvent-free reaction conditions.

• 한국농공학회논문집
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• 제52권6호
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• pp.39-48
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• 2010

Sediment yields from Imha watershed were simulated during 1993-2008 using Hydrologic Simulation Program-Fortran (HSPF). Using observed daily stream flow for 2004-2008 and hourly suspended solid concentration for three events during 2006, HSPF was calibrated and validated at the sites of Imha and Youngyang for stream flow and Dongchun and Jangpachun for sediment yield. The calibration and validation results represented high model efficiency for simulating daily stream flow and hourly suspended solid. The determination coefficients of calibration and validation were 0.90 and 0.81 for daily stream flow, and 0.91 and 0.86 for monthly stream flow, respectively. Based on model tolerances for calibration and validation of stream flow, HSPF performance for simulating stream flow represented 'very good'. The determination coefficients of calibration and validation were 0.94-0.96 and 0.95 for hourly sediment yields, respectively. The average yearly sediment yield during 1993-2008 was 122,290 ton/year and most of sediment yield (77 % of total yield) were generated from June to August. The calibrated HSPF simulated well the movement of water and eroded soil within Imha watershed.

• Journal of Mechanical Science and Technology
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• 제19권10호
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• pp.1939-1949
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• 2005

Many studies have been conducted to increase regression rate of solid fuel in hybrid rocket. One of them resorts to swirl flow since it can extend the residence time of oxidizer in the fuel grain. Also, metal wires may lead to increase the regression rate of solid fuel as shown in solid propellants. In this study, a series of experiments was designed to investigate the enhancement of regression rate of solid fuel by embedded metal wires and by fuel port grain. And fuel port was designed with a helical configuration to attempt to induce swirl flow. PMMA with gaseous oxygen is the solid fuel used for investigation. Test results showed that embedded metal wires turned out to be ineffective method because only $3-4\%$ increases in regression rate were observed. However, fuel port grain configuration yields higher burning performance of up to $50\%$ increase in regression rate. Also pitch number as well as total impulse was found to be a design variable.

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.1-7
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• 1990

We present a theoretical investigation on the etching of an Al solid by $SiCl_4$ molecules at a collision energy of 600 eV. The classical trajectory method is employed to calculate Al etching yields, degree of anisotropy, kinetic energy distribution and angular distribution. The calculated results are compared with the reaction of a Cu solid by $SiCl_4$. The major products of the reaction are aluminum monomers and dimers together with considerable quantities of multimers. The Al solid shows better etching yield and better anisotropy than the Cu solid. This is consistent with the problem in the CMOS micro-fabrication of the CuAl and CuAlSi alloys. The relevance of these calculations for the dry etching of CuAl alloy is discussed.

• Journal of Microbiology and Biotechnology
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• 제32권3호
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• pp.317-323
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• 2022

Solid-state fermentation using hulled barley was carried out to produce enzymes and β-glucan. The one-factor-at-a-time experiments were carried out to determine the optimal composition of the basal medium. The modified synthetic medium composition in liquid-state fermentation was determined to be 70 g/l hulled barley, 0 g/l rice bran, 5 g/l soytone, and 6 g/l ascorbic acid. Optimal pretreatment conditions of hulled barley by solid-state fermentation were evaluated in terms of maximum production of fungal biomass, amylase, protease, and β-glucan, which were 1.26 mg/g, 31310.34 U/g, 2614.95 U/g, and 14.6% (w/w), respectively, at 60 min of pretreatment condition. Thus, the solid-state fermentation process was found to enhance the overall fermentation yields of hulled barley to produce high amounts of enzymes and β-glucan.

• Applied Biological Chemistry
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• 제33권1호
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• pp.8-13
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• 1990

우리나라에서 생산되는 장려품종 중 팔달, 단엽, 장백, 백운, 장엽콩과 재래종 중 검정콩, 갈색아주까리콩 등 7품종을 대상으로 형태적 특성과 표피의 색, 고형분 및 단백질의 추출 수율, 콩의 색소용출속도 등을 조사하였다. 그 결과 콩 개체의 무게는 갈색아주까리콩이 가장 높고 단엽, 장백이 가장 낮은 값을 보였다. 표피의 색에서는 'L'값은 장백이 가장 높았으며 팔달, 백운, 장엽, 단엽 등도 비교적 높은 'L'값을 나타내었다. 'a', 'b'값에서는 장엽이 높았고 검정콩과 갈색아주까리콩이 비교적 낮은 'b'값을 보였다. 콩을 마쇄하여 물로 추출할 때 고형분과 단백질의 수율은 3회까지 대부분이 추출되었으며 이때 이들의 수율은 각각 73.2 %, 83.2 %이었다. 콩 표피의 색소의 용출은 추출온도와 시간에 따라 큰 영향을 받았다. 평형에 도달한 흡광도(A)와 추출온도(T)와의 관계는 A=aT+b의 관계로 표시할 수 있었으며, 색소용출 속도와 온도와의 관계는 $60^{\circ}C$를 중심으로 두개의 직선관계가 있었다. 이 관계에서 계산된 활성화에너지는 고온보다 저온이 더 높았고, Local 1과 Local 2가 가장 높은 활성화에너지 값을 보여 주었다.