• 한국식품영양학회지
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• 제23권3호
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• pp.419-427
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• 2010

The focus of the current study was to investigate the physicochemical properties of a corn starch-sponge matrix prepared at a low concentration below gel forming by freeze-drying. The effect of variables(starch concentration, heating temperature, and heating hold time) on the physicochemical properties of the samples was analyzed by response-surface methodology. Regression models on the properties of samples such as hardness, springiness, and water solubility index(WSI) showed high correlation coefficients(r>0.95) and significant F values, but regression models for the other properties(swelling power, apparent viscosity, reducing sugar content, and digestibility) showed them to have relatively low significance. Sample hardness of sample showed the highest value at condition of $90^{\circ}C$ and 5%, whereas springiness was at a maximum at $130^{\circ}C$ and 5%. Also, at 1% of starch concentration, mechanical properties were greatly decreased as the relative humidity increased, compared with the 3% and 5%, especially in the hardness of samples. The WSI showed an increasing trend with heating temperature regardless of starch concentration. Overall, the physicochemical properties of freeze-dried corn starch-sponge matrix were influenced much more by starch concentration and heating temperature than by heating hold time. The results of this study show that the basic properties of freeze-dried corn starch-sponge matrix can be used for the specific food applications or as a functional material for its stability.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.425.2-425.2
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• 2002

The purpose of this study was to prepare thermo-sensitive solid-lipid nanoparticles (SLNs) with a lipid melted at human body temperature and to evaluate physicochemical properties of SLNs containing retinol. anti-wrinkle agent. as a model drug. SLNs were prepared using a high pressure homogenizing method. The SLNs were composed of retinol as a model drug. thermo-sensitive lipid (DS-CBS) as a lipid core. and egg phosphatidylcholine and Tween 80 as surfactants. Manufacturing variables such as homogenization pressure. (omitted)

• Geomechanics and Engineering
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• 제15권5호
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• pp.1091-1100
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• 2018

In this study, the relationships between hydraulic conductivity of GCLs and physico-chemical properties of bentonites were assessed. In addition to four factory manufactured GCLs, six artificially prepared GCLs (AP-GCLs) were tested. AP-GCLs were prepared in the laboratory without bonding or stitching. A total of 20 hydraulic conductivity tests were conducted using flexible wall permeameters ten of which were permeated with distilled deionized water (DIW) and the rest were permeated with tap water (TW). The hydraulic conductivity of GCLs and AP-GCLs were between $5.2{\times}10^{-10}cm/s$ and $3.0{\times}10^{-9}cm/s$. The hydraulic conductivities of all GCLs to DIW were very similar to that of GCLs to TW. Then, simple regression analyses were conducted between hydraulic conductivity and physicochemical properties of bentonite. The best correlation coefficient was achieved when hydraulic conductivity was related with clay content (R=0.85). Liquid limit and plasticity index were other independent variables that have good correlation coefficients with hydraulic conductivity (R~0.80). The correlation coefficient with swell index is less than other parameters, but still fairly good (R~0.70). In contrast, hydraulic conductivity had poor correlation coefficients with specific surface area (SSA), smectite content and cation exchange capacity (CEC) (i.e., R < 0.5). Furthermore, some post-test properties of bentonite such as final height and final water content were correlated with the hydraulic conductivity as well. The hydraulic conductivity of GCLs had fairly good correlation coefficients with either final height or final water content. However, those of AP-GCLs had poor correlations with these variables on account of fiber free characteristics.

• 한국토양비료학회지
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• 제42권3호
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• pp.160-166
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• 2009

We estimated site productivity for unstocked land based on the relationship between site index (i.e., average height of dominant trees at fixed age) and soil physico-chemical properties of Pinus densiflora stands. Site index relates to a direct method of determining a tree's response to a specific environment such as forest soil and climate conditions. We selected 78 sites in 22 P. densiflora stands of central temperate forest zone, and sampled soils for physicochemical analyzing. And 13 properties of soils were statistically treated by stepwise regression. In the degree of contribution of the variables to site index, the highly effective variables in A horizon were OM, clay content, sand content, available $P_2O_5$, and Exch. $Ca^{{+}{+}}$ inorder, and in B horizon T.N., O.M., Soil pH, cation exchange capacity(C.E.C.), and sand content in order. In both A and B horizon of the soil for P. densiflora stands, the variables commonly contributed to the site index were sand content and OM. These results may be useful to provide not only important criteria for establishment of Pinus densiflora stand sespecially in unstocked land but also aguidance for reforestation.

• 한국식품조리과학회지
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• 제27권6호
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• pp.803-814
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• 2011

The new version of sikhye(sweet rice drink) was prepared by adding sweet pumpkin (SP) in order to improve customers' preferences for sikhye by modifying the color, and flavor, as well as health functionality. The independent variables were sweet pumpkin amount(0, 2, 4, 6, and 8% malt powder extract) and storage periods(0, 3, 6, 9, and 12 days). Each sample was measured by using physicochemical and sensory evaluations, and results were statistically tested to examine significant differences among samples. pH increased with higher amounts of added pumpkin. As additional levels of sweet pumpkin increased, the Hunter's L value decreased, whereas the b value increased. In a consumer acceptance test, all characteristics except for sweetness were significantly different at p<0.05. The overall acceptability, including yellowness, malt aroma, and sweetness in the pumpkin added sample was estimated to be better than the comparative sample was. There was no significant difference between SP4, SP6, and SP8, but SP2 showed a lower preference than other samples.

• 한국조경학회지
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• 제31권6호
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• pp.85-94
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• 2004

This study was carried out to analyze physicochemical properties according to the soil height and to the six types of sites that were used as planting ground in the reclaimed land from the sea, Gwangyang Bay. The physicochemical properties of the soil types were tested by t-test(p<0.01, 0.05), at each of the 6 planting ground sites(p<0.01, 0.05), and at each height(p<0.01) of the planting grounds. These areas were tested by ANOVA and were significantly different. Improved soil was better than reclaimed soil from the sea for Zelkova growth because the improved soil contained lower amounts of pH, ECe, N $a^{+}$, $Ca^{++}$, $Mg^{++}$ SAR. Due to freedom from variables such as salt content in the underground as well as the physical and chemical disturbance of the soil, favorable planting ground for tree growth was recorded at the higher grounds than at the lower ones. Soil detriment to the tree growth in the studied sites included elements such as soil hardness, and the distribution of sodium in the tree root systems. The planting grounds for the favorable growth of landscape trees were determined in the following order: the grounds of mounding> the coved ground of improved soil, and the filled ground of improved soil.l.l.l.

• Journal of Dairy Science and Biotechnology
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• 제36권3호
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• pp.164-170
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• 2018

본 연구에서는 CPP와 CSO를 사용하여 약 187~282 nm 크기의 균일한 구형의 나노 복합체를 성공적으로 제조하였다. 나노 복합체는 제조 공정 요인인 CPP 농도와 pH 조절을 통해 입자 크기, 다분산 지수, 그리고 표면 전하와 같은 나노 복합체의 물리화학적 특성을 조절할 수 있음을 확인하였다. 또한 CPP/CSO 나노 복합체의 분말화 공정을 통해 분말화 된 나노 복합체의 식품 적용성을 증진시킬 수 있음을 알 수 있었으며, food-grade 물질인 CPP와 CSO를 사용하여 제조한 나노 복합체는 향후 잠재적인 칼슘 전달체로써 식품 산업에 이용될 수 있을 것으로 기대된다.

• 한국축산식품학회지
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• 제39권5호
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• pp.831-843
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• 2019

The purposes of this research were to form chitosan oligosaccharide (CSO)/A2 ${\beta}$-casein nano-delivery systems (NDSs) and to investigate the effects of production variables, such as CSO concentration levels (0.1%, 0.2%, and 0.3%, w/v) and manufacturing temperature ($5^{\circ}C$, $20^{\circ}C$, and $35^{\circ}C$), on the production and physicochemical characteristics of CSO/A2 ${\beta}$-casein NDSs to carry resveratrol. The morphological characteristics of CSO/A2 ${\beta}$-casein NDSs were assessed by the use of transmission electron microscopy (TEM) and particle size analyzer. High-performance liquid chromatography (HPLC) was applied to determine the entrapment efficiency (EE) of resveratrol. In the TEM images, globular-shaped particles with a diameter from 126 to 266 nm were examined implying that NDSs was successfully formed. As CSO concentration level was increased, the size and zeta-potential values of NDSs were significantly (p<0.05) increased. An increase in manufacturing temperature from $5^{\circ}C$ to $35^{\circ}C$ resulted in a significant (p<0.05) increase in the size and polydispersity index of NDSs. Over 85% of resveratrol was favorably entrapped in CSO/A2 ${\beta}$-casein NDSs. The entrapment efficiency (EE) of resveratrol was significantly (p<0.05) enhanced with an increase in manufacturing temperature while CSO concentration level did not significantly affect EE of resveratrol. There were no significant (p<0.05) changes observed in the size and polydispersity index of NDSs during heat treatments and storage in model milk and yogurt indicating that CSO/A2 ${\beta}$-casein NDSs exhibited excellent physical stability. In conclusion, the CSO concentration level and manufacturing temperature were the crucial determinants affecting the physicochemical characteristics of CSO/A2 ${\beta}$-casein NDSs containing resveratrol.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.102-111
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• 2010

This study was conducted to investigate the optimal conditions of collagen extraction from scales of yellowfin tuna (Thunnus albacares) using surface response methodology. Four independent variables of NaOH concentration and pretreatment fime in alkali pretreatment and enzyme concentration and treatment time in enzyme hydrolysis were used to predict a model equation for the collagen yield. The determinant coefficient ($R^2$) for the equation was 0.906. The values of the independent variables for the maximum yield were 0.32 N NaOH, 16.38 h alkali pretreatment time, 0.18% enzyme concentration, and 31.02 h enzyme treatment time. In the physicochemical properties of tuna scale collagen, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of tuna scale collagen showed the same migration distances as that of calf skin collagen. The amide A, I, II, and III regions of tuna scale collagen in Fourier transform infrared measurements were shown in the peaks of 3,414 $cm^{-1}$, 1,645 $cm^{-1}$, 1,553 $cm^{-1}$, and 1,247 $cm^{-1}$, respectively. The amount of imino acids in tuna scale collagen was 18.97% and the collagen denaturation temperature was $33^{\circ}C$. The collagen solubility as a function of NaCl concentration decreased to 4% NaCl (w/v) and the collagen solubility as a function of pH was high at pH 2-4 and sharply decreased from pH 4 to pH 7. Viscosity of the collagen solution decreased continuously until $30^{\circ}C$ and this decreasing rate slowed in the temperature range of $35-50^{\circ}C$.

• 한국수산과학회지
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• 제27권1호
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• pp.13-26
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• 1994

본 연구에서는 우리나라의 연근해에서 생산되는 해조류를 이용하여 압출 성형물을 제조하기 위하여 단축스쿠류 압출성형기를 이용, corn grits에 미역 분말을 첨가하여 압출성형시켰을 때 일어나는 이화학적 특성변화를 반응표면 실험계획법에 의하여 분석하였다. 미역분말을 첨가한 corn grits압출성형물의 이화학적 측정치인 각 종속변수들간의 단순상관관계를 보면 밀도는 팽화율, 명암도, 파단강도는 수분용해 지수, 명암도, 수분흡수지수는 수분용해도지수에서 유의차를 나타내었다. 독립변수인 수분함량($15{\sim}21\%$), 미역분말함량($10{\sim}30\%$) 및 토출구온도($95{\sim}115^{\circ}C$)의 주어진 범위에서 각 종속변수인 이화학적 특성에 대한 영향을 3차원 반응표면 회귀분석을 하였을 때, 팽화율은 수분함량이 감소하고 토출구 온도가 증가할 때 증가하였으며, 밀도는 수분함량과 미역분말함량이 증가함에 따라 증가하는 것으로 나타났다. 파단강도는 수분함량과 미역분말함량이 증가함에 따라 증가하는 것으로 나타났다. 파단강도는 수분함량이 증가함에 따라 증가하는 반면, 미역분말함량에 따라서는 감소하는 경향이었다. 수분용해도지수는 수분함량이 증가할수록 증가하는 경향으로 나타났고, 명암도는 대체로 미역함량이 증가함에 따라 감소하는 경향을 보여주었다.