• 대한화학회지
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• 제19권5호
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• pp.351-354
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• 1975

2-Phenylethyl tosylate를 피리딘 및 p-톨릴-N,N-디메틸아닐린과 反應시켜 대응하는 4級 암모늄鹽을 合成하여 NMR 및 IR로서 4級鹽을 確認하였고 그의 物理 및 化學定數를 比較하였다. 本實驗에서 얻은 2-phentylethyl pyridinium tosylate는 benzyl pyridinium tosylate와 마찬가지 方法으로 아세톤 중에서도 合成이 可能하나 아세토니트릴中에서 收率이 훨씬 좋음을 알았다.

• BMB Reports
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• 제49권12호
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• pp.655-661
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• 2016

Polymer brush is a soft material unit tethered covalently on the surface of scaffolds. It can induce functional and structural modification of a substrate's properties. Such surface coating approach has attracted special attentions in the fields of stem cell biology, tissue engineering, and regenerative medicine due to facile fabrication, usability of various polymers, extracellular matrix (ECM)-like structural features, and in vivo stability. Here, we summarized polymer brush-based grafting approaches comparing self-assembled monolayer (SAM)-based coating method, in addition to physico-chemical characterization techniques for surfaces such as wettability, stiffness/elasticity, roughness, and chemical composition that can affect cell adhesion, differentiation, and proliferation. We also reviewed recent advancements in cell biological applications of polymer brushes by focusing on stem cell differentiation and 3D supports/implants for tissue formation. Understanding cell behaviors on polymer brushes in the scale of nanometer length can contribute to systematic understandings of cellular responses at the interface of polymers and scaffolds and their simultaneous effects on cell behaviors for promising platform designs.

• Journal of Applied Biological Chemistry
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• 제49권2호
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• pp.39-47
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• 2006

Incorporation of bioactive compounds such as vitamins, probiotics, bioactive peptides, and antioxidants into Nutrient Delivery System (NDS) for 'nanofood' provides simple way to develop novel functional foods that may have physiological benefits or reduce risks of diseases. As vital nutrient in nanofood, proteins possess unique functional properties including ability to form gels and emulsions, which allow them to be ideal nanofood materials for encapsulation of bioactive compounds. Based on protein physico-chemical properties, this review describes potential role of nanofood materials for development of NDS in hydrogel form, micro-or nano-particles. Applications of these nanofood materials to protect delivery-sensitive nutraceutical compounds are illustrated, and impacts of particle size on release properties are emphasized.

• Korean Chemical Engineering Research
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• 제59권4호
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• pp.644-651
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• 2021

Alkyl amines are widely used in various industries. Nowadays these are also used in CO₂ capture technology because amines react with CO₂ and remove it from the flue gas. To make the amines more compatible towards this technology, physico chemical properties may be altered by mixing with other solvents. In the present report, we measured the refractive properties of pure diisopropylamine (DIPA) (1) + isomeric butanol (2) at 298.15 K to 308.15 K. The 𝚫n values were positive for DIPA + n-butanol or sec-butanol or isobutanol or tert-butanol mixtures. The measured data was correlated with Redlich-Kister equation. The excess molar volume data were predicted from refractive index data using Nakata and Sakurai model. The experimental data were also predicted by various correlations, and the prediction capability of these correlations was reported through standard deviation. Further, the deviation in refractive index (𝚫n) data was interpreted by the consideration of specific molecular interactions between DIPA and isomeric butanol.

• 공업화학
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• 제2권4호
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• pp.356-362
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• 1991

가황계에 따른 NR/BR 블렌드의 물리적 기계적 특성의 변화를 가교밀도의 차이로 해석하였다. 경화제의 비율 및 함량이 증가함에 따라 가황속도 및 최대 토오크는 증가를 보였으며, 가교밀도도 증가하였다. 가교밀도의 증가에 따라 경도, 300% 모듈러스, 반발탄성 및 마모특성은 증가를 보인 반면에 발열에 의한 온도 상승 및 $60^{\circ}C$에서의 tan $\delta$는 감소를 보였다. 따라서 높은 하중이 가해지는 트럭/버스 타이어의 트레드 부위에 사용하는 경우 회전저항이 적은 semi-EV 가황계가 가장 적절한 가황 시스템으로 판단되었다.

• Applied Biological Chemistry
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• 제40권4호
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• pp.301-306
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• 1997

찰성, 부정형, plump endosperm 등의 유전자를 결합시킨 보리 isogenic lines의 이화학적 품질특성과 취반특성에 대한 제 특성을 조사하였다. 종실의 천립중은 입도가 2.5 mm 이상의 것이 가장 많은 Betzes가 가장 높았으며, 정맥율은 Franubet과 Wafranubet이 높았고, 보리쌀의 백도는 품종에 따라 큰 차이를 보였다. 배유가 부정형 전분 유전자로 구성된 Franubet이 전분함량이 가장 높았으며, 제분율도 높았다. 보리전분의 팽윤력과 물결합능력은 찰성 및 부정형 유전자를 갖는 품종이 높았다. Amylogram 특성에서 찰성의 보리는 메성에 비하여 호화 온도는 낮았고 최고점도는 높았다. ${\beta}-Glucan\;viscosity$는 품종에 따라 큰 차이를 보였는데, 특히 찰보리의 ${\beta}-glucan\;viscosity$가 가장 높았다. 취반특성중 흡수율, 용출고형물 및 퍼짐성은 찰성과 부정형 전분을 포함한 보리 품종이 Wafranubet이 가장 높았으며, 밥의 백도는 품종간에 차이가 없었다.

• 한국축산시설환경학회지
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• 제2권2호
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• pp.135-145
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• 1996

This study was carried out to investigate changes of physico-chemical properties and microbial activity during the early stage of composting with pig and chicken manure. The results were as follows; 1. The temperature was rapidly increased from the 3rd to the 7th day, and especially the pig manure compost preparing with enzyme was maintained $56^{\circ}C{\sim}69^{\circ}C$. 2. The pH range was shown $7.7{\sim}9.3$, and the pH level increased from the 3rd day to 25th day. Also after the 25th day the pH level decreased gradually. 3. The C/N ratio in the pig manure compost decreased 16.8 at the 30th day, while the compost containing enzymes decreased 19.2 at the 30th day. Chicken manure compost showed similar results at the 28 of C/N ratio at the 30th day with enzyme treatment. 4. The total ammount of sugar in pig manure compost was $6,000{\sim}7,000mg/kg$, while the chicken manure compost was $2,000{\sim}4,000mg/kg$. However, there was no significant difference in view point of enzyme treatment. 5. Cellulase, phosphatase and xylanase activity were continually increased, however amylase and urease activity were not changed during composting.

• 한국토양비료학회지
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• 제41권2호
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• pp.137-142
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• 2008

This study was conducted to evaluate the humification grade of compost, based on physico-chemical property and phyto-toxicity during the composting with three kinds of livestock manures and saw dust. The ratios of the compost, which was mixed with pig manure(P) and sawdust(S) were 4 : 6(PS-1), 5 : 5(PS-2) and 6 : 4(PS-3); poultry manure(PO) and sawdust(S) were 4 : 6(POS-1), 5 : 5(POS-2) and 6 : 4(POS-3); cow manure(C) and sawdust(S) were 4 : 6(CS-1), 5 : 5(CS-2) and 6 : 4(CS-3) by volume to volume, and they were decomposed for 60 days. In the result, the temperature in all treatments during composting rapidly increased above $65.4^{\circ}C$, and then gradually decreased to around $40^{\circ}C$. At 60 day, after the treatment, pH 5.9 ~ 8.0 at the incipient stage increased to 7.6 ~ 8.5, and the C/N ratio was 13.8 ~ 21.1 at the final composting stage. Germination Index(G.I.) showed in the range of 75.1 ~ 94.6 in all treatments at day 60. Therefore, it is likely recommended to take the best humification grade when the temperature maintains above $65^{\circ}C$ longer than a day at minimum, in the range of pH 6.5 ~ 8.5 for the final compost, under 20 of C/N ratio, and G.I. above 80. The level of G.I. above 80 should be the mature compost which could be used in the field without gas demage to crops.

• 공업화학
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• 제21권2호
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• pp.178-182
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• 2010

다양한 $TiO_2$를 담체로 한 Pt계 촉매에서 NOx, soot의 동시 제거 반응에 대한 연구를 수행하였다. 실험은 각 촉매를 NOx와 soot의 반응을 독립 또는 동시에 반응시킨 조건으로 수행하였으며 그 결과 $TiO_2$의 종류에 따라 서로 상이한 NOx 제거능력과 soot 산화력을 나타내었다. 또 NOx 독립 실험 시 생성된 $NO_2$ 양과 soot 산화시작온도가 저온으로 이동하는 정도가 관계가 있었다. 담체의 물성 중 Pt의 뭉침현상에 결정적 역할을 미치는 비표면적과 촉매의 환원력에 영향을 미치는 crystallite size가 NO의 $NO_2$ 전환반응에 밀접한 관계를 가지는 것으로 조사되었다. 따라서 반응의 중요한 인자는 촉매에 사용되는 담체의 물리화학적 특성임을 알 수 있었다.

• Food Science and Biotechnology
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• 제14권6호
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• pp.808-812
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• 2005

The effects of high pressure processing, pressure level (50, 100, 150, and 200 MPa) and pressurized time (0, 5, 10, 15, 30, 45, and 60 min) on the physico-chemical properties of pork M. longissimus dorsi were evaluated. The pH value was affected by both pressure level and pressurized time, especially at 200 MPa (P<0.05). In color measurement, $L^*$ and $a^*$-values were increased by both pressure level and pressurized time, but $b^*$-value did not differ significantly (P>0.05). Water holding capacity (WHC) was significantly decreased (P<0.05) depending on pressure level and pressurized time, while cooking loss was gradually increased. Warner-Bratzler shear force did not differ significantly (P>0.05) among the treatments. These results indicate that high pressure processing below 200 MPa for 1 hr had no effect on the quality of cooked meat, although some alterations were observed before cooking.