• KSBB Journal
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• 제28권6호
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• pp.356-365
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• 2013

The novel Aloe gels were prepared with dewatering and impregnation by soaking (DIS) processing of Aloe vera leaf slice at four different temperatures (25, 35, 45 and $55^{\circ}C$), using dehydration solution of 40% (w/v) polyethylene glycol (PEG4000). The PEG-impregnation to Aloe vera leaf slice during DIS was observed depending on immersion temperature, and the PEG-impregnated Aloe vera gel (PEG-i-AVG) obtained was characterized using $^1H$ NMR, FT-IR, GPC, XRD and TGA. The PEG-i-AVG had the higher levels of Aloe bioactives (glucomannan and O-acetyl contents) and better quality indices by $^1H$ NMR and FT-IR spectroscopy than those of native Aloe gel. Also, the obtained Aloe gel maintained the bimodal patterns in higher molecular weight region by GPC indicating no degradation of polysaccharide from native Aloe gel. The result observed by SEM confirmed a surface modification by forming the porous structure, and TGA result exhibited better thermal stability than that of native Aloe gel. XRD result revealed that the crystalline structure in Aloe gel was led by incorporation of PEG. Significant decrease of %insolubility and high enhancement of water solubility index were observed, respectively, and highly ordered conformation such as a helix structure was also indicated by Congo red reaction. We concluded that the modification effect for enhancing function of native Aloe gel was successfully obtained by DIS process using PEG as a dehydrating agent. These results suggested that this DIS process had a high potential for developing a new minimally processed product from Aloe vera leaf.

• 공업화학
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• 제24권6호
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• pp.650-655
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• 2013

본 연구에서는 Pd/C 촉매를 이용하여 무수말레인산(maleic anhydride) 수용액상에서 수소화 반응을 통해 호박산(succinic acid) 합성을 진행하였으며, 그에 따른 최적 공정 조건을 도출하고자 하였다. 반응 온도 및 반응시간에 따른 호박산 순도의 차이는 크지 않았으나 압력과 교반속도가 증가함에 따라 불순물의 생성이 줄고, 호박산의 순도가 증가함을 확인하였다. 실험 결과 본 수소화 반응에서는 압력과 교반속도가 기체-액체 간 물질전달저항을 감소시켜 반응속도를 증가시킬 수 있는 가장 중요한 변수임을 확인하였으며 이에 따라 압력과 교반속도에 대한 반응속도를 구하였다. 반응압력이 5 bar에서 10 bar로 2배 증가 시, 반응속도는 2.14배 증가하였으며 교반속도가 300 rpm에서 700 rpm으로 2배 증가 시, 반응속도는 2.36배 증가함을 확인할 수 있었다.

• Korean Membrane Journal
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• 제5권1호
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• pp.43-53
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• 2003

The selectivity of a gas in the carbon molecular sieve membrane (CMSM) can be expressed as the ratio of the product of the diffusivity and the solubility of two different gases. The diffusivity is also expressed as the product of the entropy and the total energy (kinetic and potential energy) in the nano-sized pore of the membrane. The present study calculates the entropic-energy and selectivity of penetrant gases such as H$_2$, O$_2$, N$_2$, and CO$_2$ from the gas-in-a box theory to physically analyze the diffusivity of penetrant gas in slit-shaped pore of CMSM focusing on the restriction of gas motion based on the size difference between penetrant gas pairs. The contribution of each energy term is converted to entropic term separately. By the conjugated calculation for each entropic-energy, the entropic effects on diffusivity-selectivity for gas pairs such as H$_2$/N$_2$, CO$_2$/N$_2$, and O$_2$/N$_2$ were analyzed within active pore of CMSM. In the activated diffusion domain, the calculated value of entropic-selectivity lies between 9.25 and 111.6 for H$_2$/N$_2$, between 3.36 and 6.0 for CO$_2$/N$_2$, and between 1.25 and 16.94 for O$_2$/N$_2$, respectively. The size decrement of active pore in CMSM had the direct effect on the reduction of translational entropic-energy and the contribution of vibrational entropic-energy for N$_2$, O$_2$, and H$_2$ was almost negligible. However, the vibrational entropic term of CO$_2$ might extravagantly affect on the entropic-selectivity.

• 공업화학
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• 제30권1호
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• pp.34-38
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• 2019

탄산화 공정을 위한 Ca 추출원으로 시멘트 산업부산물을 사용하였다. ICP와 XRD 분석을 통하여 시멘트 산업부산물은 대부분 CaO와 KCl로 구성되어 있음을 확인하였다. 최적화된 추출용제의 종류 및 농도는 1.5 M of hydrochloric acid이며 최적의 고액비는 0.1 g/mL이었다. 추출 성능 실험 결과를 통해 양이온의 추출효율은 이온 결합 형태 및 용해도에 의존함으로 판단되었다. 또한 추출 공정 후, 첨가물의 종류 및 주입 순서에 따라 선택적으로 양이온이 분리될 수 있음을 확인하였다. pH를 9.5, 13으로 조절하기 위하여 NaOH를 주입하였을 때 불순물과 $Ca(OH)_2$가 침전되었으며, $C_2H_5OH$를 주입한 경우 KCl 형태로 분리된 K가 침전되었다.

• Animal Bioscience
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• 제36권11호
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• pp.1747-1756
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• 2023

Objective: The objective of this study was to evaluate the effects of four different cooking techniques viz: boiling, grilling, microwave, and frying; on the physicochemical characteristics of camel meat. Methods: Protein composition and their degradation as well as biochemical and textural changes of camel meat as influenced by cooking methods were investigated. Results: The highest cooking loss (52.61%) was reported in microwaved samples while grilled samples showed the lowest cooking loss (44.98%). The microwaved samples showed the highest levels of lipid oxidation as measured by thiobarbituric acid reactive substances, while boiled samples showed the lowest levels (4.5 mg/kg). Protein solubility, total collagen, and soluble collagen content were highest in boiled samples. Boiled camel meat had lower hardness values compared to the other treated samples. Consequently, boiling was the more suitable cooking technique for producing camel meat with a reduced hardness value and lower lipid oxidation level. Conclusion: The camel meat industry and camel meat consumer can benefit from this research by improving their commercial viability and making consumers aware about the effects of cooking procedures on the quality of camel meat. The results of this study will be of significance to researchers and readers who are working on the processing and quality of camel meat.

• Natural Product Sciences
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• 제11권1호
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• pp.27-32
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• 2005

The purpose of this study is to evaluate the inhibitory effects of Resina Pini against Streptococcus mutans (S. mutans) that is one of the major causes of dental caries and oral diseases. Topically applied Resina Pini (RP) would be incorporated in saliva and thus the factor associated with water solubility should be considered. In this paper, therefore, effects of various treatment for RP and activities of water extracts from unprocessed and processed RP were compared. The crude RP (RP1) and the recrystallized RP (RP2) in ethanol solution showed strong antimicrobial activities (d.>15mm) against S. mutans. All RP samples exhibited considerable inhibitory effect against glucosyltransferase produced by S. mutans $(IC_{50}=91.2\;to\;276.2\;{\mu}g/ml)$. The very considerable increase in cellular permeability of S. mutans was observed with RP1, RP2 and their water extracts. These results suggest that RP1 and RP2 may be a potential source for pharmaceutical products used for prevention and/or treatment of dental caries and periodontal disease.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2016-2022
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• 2013

Ionically modified ${\beta}$-cyclodextrins, which have excellent water-solubility, have been interested in purification technology as well as drug carrier system. The present study summarizes the synthesis and characterization of cationic and anionic ${\beta}$-cyclodextrin (${\beta}$-CyD) products using by polycondensation. The oligo (${\beta}$-CyD)s are synthesized from ${\beta}$-CyD, epichlorohydrin (EP) and choline chloride (CC; for cationic polymer) or chloroacetic acid (CAA; for anionic polymer) through one step polycondenstaion process. Unlike the previous studies, we successfully purified the ionic ${\beta}$-CyD condensation products from the ${\beta}$-CyD reaction mixtures and accomplished a great level of structural analysis. The detailed structural analysis of these ionic ${\beta}$-CyD compounds is done by $^1H$ NMR, MALDI-TOF as well as GPC analysis and confirms the formation of oligomers with a few units of ${\beta}$-CyD. We found that the sequence of reactant addition also could effect on the molecular weight of the resulting product as well as the molar ratio of the reactants. Finally, we used the cationic and anionic ${\beta}$-CyD oligomers for fabricating multilayer films by layer-layer process.

• Preventive Nutrition and Food Science
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• 제17권1호
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• pp.87-91
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• 2012

Three oat cultivars and one oat breeding line were evaluated for chemical, hydration and pasting properties. Protein, starch and ${\beta}$-glucan levels ranged 11.13~14.37, 56.37~64.86 and 3.44~4.76%, respectively. The oat cultivars Daeyang and Seonyang contained higher ${\beta}$-glucan levels of 4.76 and 4.35%. The Daeyang variety had a higher water absorption index (WAI) of 2.83~3.35 (g/g), but a lower water solubility index (WSI) of 8.67~11.08%. Daeyang and Seonyang cultivars showed higher peak and trough viscosity, but lower breakdown and setback, indicating that they easily swell, and thus could possibly provide the desirable viscosity of an oat product. The ${\beta}$-glucan levels were correlated positively with WAI, peak and trough viscosity, and negatively to WSI, breakdown and setback viscosity.

• 대한기계학회논문집A
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• 제33권9호
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• pp.913-921
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• 2009

In this study, supercritical nano plating was performed to observe its effect on materials. Using supercritical carbon dioxide as a solvent, we observed how different pressures and temperatures of the supercritical fluid affected the process and its outcome. The plating current increases as pressure increases from 8 MPa to 16 MPa, but it decreases after that. Similarly, the plating current increases as temperature is increased from $35^{\circ}C$ to $45^{\circ}C$, but the current decreases after that. Also, the thickness of the wet electrolyte plating is about $35\sim50{\mu}m$, while the thickness of the plating done using supercritical fluid is about $20\sim25{\mu}m$. At the results, It to it is considered that supercritical nano plating enable to form more thin and stable plating than wet electroplating methods. Also both of the electroplating methods could be affected plating quality by surface condition, and the supercritical nano plating has been confirmed to product more uniform plating surface than wet electroplating.

• Journal of Nutrition and Health
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• 제14권1호
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• pp.26-33
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• 1981

Crocin was extracted from Gardenia fructus in order to manufacture a natural food dye. In the extraction and purification process methanol and ethanol were used as the most Suitable solvent selected in preliminary test and 9.28%g/100g of Cretin product in 99.89% of purity was acquired. The lethal dose of Cretin administered in mouse by intra peridoneal was 5.36g/kg which is much lower toxic than any other. The toxic dose which caused diarrhoea in rat was 2.55g/kg and maximum no effect level was found to be 272mg/kg. From the $1%{\sim}2.5%$ content of Crocin in rat diet reduction of body weight appeared and GTP and GOT (Transaminase) value in creased significantly. Crocin showed a good properties of tolerating acid, alkali, sunlight, reductant, oxidant, and salt compared with tar dyes. The range from 100 ppm to 500ppm bring out bright $yellow{\sim}orange$ color, the most effective color, with a good solubility in water-slightly in oil. The acceptable daily intake of crocin was calculated as 2.72mg/kg based on maximum no effect dose (2% additive dose).