• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.417-426
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• 1997

Rice bran protein hydrolysates were prepared and some of their physicochemical properties were investigated to utilize rice bran as starting material for functional food ingredient. Rice bran proteins (RBP) were prepared from defatted rice bran by alkaline extraction and isoelectric precipitation. The enzyme for hydrolysis of RBP was selected through measuring relative activity by pH-drop method and comparing the degree of hydrolysis (DH) of hydrolysates. The enzymatic hydrolysates prepared by $Esperase^{\circledR}$ treatment were partitioned into two fractions by ultrafiltration(UF) with a 10 kDa molecular weight cut-off membrane. Each fraction was applied to a cholic acid-conjugated ${\omega}-aminohexyl$ Sepharose 4B column and the bile acid-binding components were obtained by eluting with deoxycholate. Gel permeation chromatography on a Sephadex G-50 column revealed that molecular weight of the bile acid-binding fraction of UF permeate was distributed in ranges of $2\;kDa{\sim}10\;kDa$ and $0.2\;kDa{\sim}0.6\;kDa$. Three peaks (R-1, R-2 and R-3) were obtained by prep-HPLC of bile acid-binding fraction of UF retentate and analyzed for total and free amino acid composition. The results showed that proline content of the bile-acid binding polypeptides and peptides was four times as much as that of rice bran protein and that the peak corresponding to higher average hydrophobicity had a higher free amino acid content. Average hydrophobicity slightly increased with enzymatic hydrolysis.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.447-450
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• 2000

Microorganism, including some bacteria isolated from soil, were found to secrete an extracellular soymilk-clotting enzyme. Using this bacterial enzyme experiments were carried out to optimize the hydrolyzing conditions for the production of soy peptides. The soy peptides produced by hydrolyzing 11S globulin with enzyme treatment at $65^{\circ}C$, pH 6.1, for 1hr were found to have a accessible possibility. The obtained coagulum by enzymatic reaction was very flocculation with fine structural formation. Properties of peptide Y and W of the enzyme hydrolysates at pH 6.1 were superior to that of isoelectric precipitation because these peptides were miscible with water in all proportions.

• Journal of the Korean Electrochemical Society
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• v.20 no.1
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• pp.18-25
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• 2017

In this review, I have summarized the solar water splitting research based on the organic metal halide perovskite material, which has recently been spotlighted worldwide. Significantly, to date, recent reports have been categorized as photovoltaic-electrolyzer configuration and integrated photoelectrolysis. Research in this field is still in its early stages, and it is necessary to develop an effective protection film and manufacture a high-voltage tandem cell in the future.

• Applied Chemistry for Engineering
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• v.17 no.6
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• pp.638-643
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• 2006

Pyrolytic reaction study of dichloromethane ($CH_{2}Cl_{2}$) in excess hydrogen was performed to investigate pyrolytic reaction pathways at a pressure of 1 atm with residence times of 0.3~2.0 sec in the temperature range of $525{\sim}900^{\circ}C$. A constant feed molar ratio $CH_{2}Cl_{2}$:$H_{2}$ of 4:96 was maintained through the experiment. Reagent loss and product formation were monitored by using an on-line gas chromatograph, where batch samples were analyzed by GC/MS. Complete destruction(99%) of the parent reagent was observed at temperature near $780^{\circ}C$ with residence time over 1 sec. Major products observed were $CH_{3}Cl$, $CH_{4}$, $C_{2}H_{4}$, $C_{2}H_{6}$, and HCl. Minor products included $CHClCCl_{2}$, CHClCHCl, $CH_{2}CHCl$, and $C_{2}H_{2}$. The pyrolytic reaction pathways to describe the important features of intermediate product distributions and reagent loss, based upon thermodynamic and kinetic principles, were suggested. The results of this work provided a better understanding of pyrolytic decomposition processes which occur during the pyrolysis of $CH_{2}Cl_{2}$ and similar chlorinated methanes.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.178-185
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• 2019

Three spherical quaternary composites composed of metal/metal oxide/high explosive/oxidizer were prepared by a crystallization/agglomeration process. From the characteristics of composites by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), the shortening of the decomposition zone of high explosives in the quaternary composite was observed, which may be attributed to the autocatalytic reaction caused by $ClO_2$ or HCl which are ammonium perchlorate (AP) degradation products. The activation energy analysis showed that the activation energy abruptly decreases at the end of the decomposition zone of high explosives, and it was considered to be caused by $HNO_2$ which is common in decomposition products of high explosives. The activation energy predicted from complex pyrolysis results by the distributed activation energy model (DAEM) showed much better in accuracy than those by model-fitting methods such as Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa models.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.245-245
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• 2004

현재 한국원자력 연구소에서 개발되고 있는 사용후 핵연료의 차세대관리기술은 산화물 핵연료를 전해환원시켜 금속으로 관리하는 기술이다. 이 공정에서 발생된 LiCl 폐용융염은 Cs, Sr과 같은 핵분열 생성물을 함유하고 있으며, 그 자체로서 수용성이고 방사선에 분해가 잘 되므로 처분 수용기준에 맞게 안정화시켜 처리해야 한다. 현재 이를 처리하기 위한 방법으로 고온에서도 핵분열 생성물의 이온교환 및 흡착이 가능한 제올라이트 A를 이용한 이온교환 및 단순혼합 방식이 주로 적용되고 있다.(중략)

• Journal of Conservation Science
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• v.6 no.2 s.8
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• pp.149-157
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• 1997

Based on results reported in the literature, the conservation of outdoor wood, dry wood, and waterlogged wood which contained archaeological and cultural values were reviewed in a chemical point of view.

• Analytical Science and Technology
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• v.13 no.5
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• pp.549-557
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• 2000

FRIR-ATR spectrometry has been used to monitor the aqueous reactions of compounds without distinct chromophores in ultraviolet and visible regions. For example, hydrolysis reactions of ${\alpha}$-cyclodextrin and ${\gamma}$-cyclodextrin in acidic aqueous solution were studied. FTIR-ATR method has been used for the monitoring of cyclodextrin hydrolysis in 1.0 M. 0.5 M, and 0.1 M HCl solutions, respectively. We also found that the hydrolysis of ${\alpha}$-cyclodextrin produced glucose, but the hydrolysis of ${\gamma}$-cyclodextrin proceeded further to give more fragmented products than glucose.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.158-166
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• 2002

진공관형 태양열집열기의 집열성능 및 집열특성 실험을 통하여 다음과 같은 결론을 얻을 수 있었다. 1) 집열성능 실험을 통하여 진공관형 태양열집열기의 순간집열효율이 60%로 높게 나타났다. 2) 진공관형 태양열집열기의 집열특성 실험에 의해 얻어진 결론은 다음과 같다. \circled1 경사각 0$^{\circ}$일 때 집열기에 조사된 광 강도는 630W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크내의 물 132$\ell$를 8.1$^{\circ}C$ 상승시켰다. \circled2 경사각 $10^{\circ}$일 때 광강도는 615W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크내의 물의 온도를 7.3$^{\circ}C$ 상승시켰다. \circled3 경사각 20$^{\circ}$일 때 광 강도는 605W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크의 물 132$\ell$을 6.6$^{\circ}C$ 상승시켰다. 집열기에 대한 솔라시뮬레이터의 경사각이 작을수록 광 강도가 커 물탱크내의 물 온도를 크게 상승시키는 것으로 나타났다.

• Food Science and Preservation
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• v.22 no.2
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• pp.297-302
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• 2015

Calcium is one of the essential mineral for the humans due to its crucial physiological functions in the body. Calcium deficiency results in many diseases, such as osteoporosis. Therefore, calcium supplements are available as a functional food. However, most calcium supplements in the market have a limitation due to poor absorption and low bioavailability. Thus, calcium-chelated peptides for improving the absorption rate of calcium have been isolated from foods including porcine meat and bone meal (MBM), and mussel using the enzymatic hydrolysis of their protein. The hydrolysates of food were ultra-filtered in order to obtain small peptides less than 3 kDa and the Ca-binding peptides were isolated via the anion exchange chromatography. The binding activity and concentration of Ca-binding pepetides were determined. In particular, the MBM and mussel protein hydrolysates were fractionated by mono Q and Q-Sepharose, respectively. As a result, among the fractions, the fractions of MBM F2 and mussel F3 showed the highest Ca-binding activity. These results suggest that MBM and mussel protein hydrolysates can be used as calcium supplements.