• Transactions on Electrical and Electronic Materials
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• 제4권3호
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• pp.25-28
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• 2003

Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. New polymeric hydrogels based on vinyl ethers have been synthesized by the $\gamma$-initiated polymerization method. In this paper, we have studied the effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on polyvinylether of ethyleneglycol (PVEEG).

• 대한영양사협회학술지
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• 제4권1호
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• pp.99-108
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• 1998

The purpose of this study was to investigate the effect of frying methods of chickens ; deep-fat frying with raw chickens(A), with pre-cooked chickens(B) on the physicochemical properties of frying oil and fried chickens in the school foodservice. Acid, peroxide and TBA value of frying oil were significantly increased by increasing the number of frying times and those of method A were higher than those of method B. On the contrary, Iodine value was decreased significantly with increasing the number of frying times but there is no significant difference between method A and B. In fatty acids, the content of saturated fatty acid increased while that of unsaturated fatty acid decreased as the frying times increased. Also viscosity, yellowness and redness increased significantly by increasing the number of frying times. The content of vitamin $B_1 $, of fried chicken by the frying methods was not significantly different, but vitamin $B_2 $the method A was higher than by the method B. Ca, P, Na, K and Fe contents of fried chickens by the method A were higher than those by the method B.

• 한국식품과학회지
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• 제28권5호
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• pp.959-964
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• 1996

동진 품종의 현미를 2분도미, 5분도미, 7분도미로 도정하여, 도정도에 따른 쌀의 수화와 쌀가루의 이화학적 성질 및 호화 특성을 조사하였다. 쌀의 도정도가 증가하면 일반성분 중에서 단백질, 회분, 지방질, 섬유소의 함량이 감소되고, 쌀의 수분 증가량은 감소되고 SEM으로 관찰하였을 때 틈이 점점 현저하였다. 도정도가 증가할수록 쌀가루의 물결합능력, 팽윤력과 용해도는 증가하였다. 아밀로그람에서의 초기 호화온도는 도정도가 증가할수록 낮아졌고 최고점도, breakdown과 consistency는 높아졌다.

• 대한화학회지
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• 제64권5호
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• pp.259-266
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• 2020

The main purpose of this study is to examine the different physicochemical properties of spray-dried products. The carrier agents and powders after the spray-drying process were analyzed for encapsulation yield, moisture content, color parameters, total polyphenol content (TPC), antioxidant capacity (AC), bulk density, flowability, wettability, hygroscopicity, water solubility index (WSI), particle size and microstructure. The spray-drying process was carried out with different carrier agents including maltodextrin (MD) and the combination of maltodextrin and gum arabic (MD-GA) with MA/GA ratio of 70/30, dried at the inlet/outlet air temperature of 160 ℃/70 ℃, 4 bar, airflow rate of 70 ㎥·h^-1 and feed flow rate of 750 mL·h^-1. The results showed that the different carrier agents have significant influences on the physicochemical properties of the powder produced by the spray-drying method. In there, while the values of recovery efficiency and flowability of spray-dried products from MD are higher than those of spray-dried products from MD-GA combination, the opposite is true for the values of TPC, AC, bulk density and wettability, whereas hygroscopicity and WSI values are equally represented in both products.

• Ecology and Resilient Infrastructure
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• 제4권2호
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• pp.93-96
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• 2017

Spatial variations of physicochemical and microbiological variables were examined to understand spatial heterogeneity of those variables in intertidal flat. Variograms were constructed for understanding spatial autocorrelations of variables by a geostatistical analysis and spatial correlations between two variables were evaluated by applications of a Cross-Mantel test with a Monte Carlo procedure (with 999 permutations). Water content, organic matter content, pH, nitrate, sulfate, chloride, dissolved organic carbon (DOC), four extracellular enzyme activities (${\beta}-glucosidase$, N-acetyl-glucosaminidase, phosphatase, arylsulfatase), and bacterial diversity in soil were measured along a transect perpendicular to shore line. Most variables showed strong spatial autocorrelation or no spatial structure except for DOC. It was suggested that complex interactions between physicochemical and microbiological properties in sediment might controls DOC. Intertidal flat sediment appeared to be spatially heterogeneous. Bacterial diversity was found to be spatially correlated with enzyme activities. Chloride and sulfate were spatially correlated with microbial properties indicating that salinity in coastal environment would influence spatial distributions of decomposition capacities mediated by microorganisms. Overall, it was suggested that considerations on the spatial distributions of physicochemical and microbiological properties in intertidal flat sediment should be included when sampling scheme is designed for decomposition processes in intertidal flat sediment.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.979-984
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• 2007

The physicochemical properties of the exopolysaccharide (EPS) produced by marine bacterium Zoogloea sp. KCCM10036 were investigated. Two types of isolated EPSs were shown to have average relative molecular masses $(M_r)\;of\;4.07{\times}10^6$ of CBP (cell-bound polysaccharide) and $3.43{\times}10^6$ of WSP (water-soluble polysaccharide), respectively. When the CBP was utilized as an emulsifier, it stabilized the emulsifier, for up to 148 h. Compared with other commercially available hydrocolloids such as xanthan gum, the Tween series, and Triton, the CBP showed much better emulsifying capability on a water-in-oil system. Phase separation occurred in the Tween series after 24 h, whereas the emulsion was better stabilized by the CBP. The CBP thus has potential as an emulsifying agent in commercial emulsions. The flocculating activity was also greatest at 0.01% (w/v) and decreased at higher concentrations than the optimized concentration of the WSP and CBP. The results also showed that both types of expolysaccharides from Zoogloea sp. had excellent flocculating activity.

• Agricultural and Biosystems Engineering
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• 제2권2호
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• pp.59-62
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• 2001

The starch content of apples, which is related to the maturity and ripeness, was quantified by using a computer vision system. The stained area was measured by image analysis when an apple slice was stained with KI/I$_2$ solution. The ratio of stained area of the apple slice to its whole area, so called the starch index, was defined as an indicator of the starch content. When Tsugaru apples were manually sorted into immature, turing and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. The starch index had relationships to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1%, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1% significant level, it had the correlation with the density and moisture content.

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.234-238
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• 2007

The effects of ultra-fine pulverization on the physicochemical properties of rice starch (RS) were investigated using a high impact planetary mill. After pulverization, RVA characteristics, peak viscosity, break down, and set back values of RS decreased from 274.75 to 9.42 RVU, 214.46 to 6.17 RVU, and 87.80 to 17.00 RVU, respectively. The pasting properties also changed significantly. X-Ray diffractogram revealed RS had four A-type peaks, which disappeared after pulverization. The peak temperature and gelatinization enthalpy of RS using differential scanning calorimetry (DSC) were 13.99 J/g at $75.14^{\circ}C$, whereas the pulverized RS (PRS) had two peaks, 0.13 J/g at $63.88^{\circ}C$ and 1.23 J/g at $101.24^{\circ}C$. DSC measurement showed the retrogradation degree of PRS was lower than that of RS after storage at 4 and $25^{\circ}C$. The enzymatic (${\alpha}$-amylase) digestibilities of RS and PRS were 72.7 and 77.3%, respectively.

• 농업생명과학연구
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• 제50권1호
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• pp.137-146
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• 2016

This experiment was designed to assess the physical and chemical properties of growing media substituted with a range of increasing concentrations of pretreated wood and to relate these properties to plant growth responses. For preparing the growing media, each material was combined with rural soil, peat, perlite and pretreated wood. Physicochemical properties studied were similar to ideal substrate ranges for plant growth on growing media, including pretreated wood. Physical properties were also well maintained over time. In comparison to plants growing in 100% rural soil, tall fescue(Festuca arundinacea) in the prepared growing media achieved better growth, especially when using the 50% rural soil + 50% PPW(peat + perlite + pretreated wood, 3:1:6(w/w/w)) and 30% rural soil + 70% PPW (peat + perlite + pretreated wood, 3:1:6(w/w/w)), and showed improved germination percentage. We confirmed the potential use of growing media, including pretreated wood. Furthermore, our results show a correlation among the physicochemical properties of tall fescue(Festuca arundinacea); physical properties were significantly influenced by germination and aerial parts. The root length of physicochemical properties was correlated with bulk density and organic compound (p<0.01).

• 한국식생활문화학회지
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• 제19권5호
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• pp.491-498
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• 2004

In order to study the quarantine and sanitization methods for dried red pepper, comparative effects of commercial fumigation (methyl bromide/MeBr, $phosphine gas/PH_{3}$ and gamma irradiation (5, 10 kGy) were investigated in terms of its physicochemical properties. There were no noticeable chances in pH and soluble solids among the untreated control, irradiated and fumigated samples soon after treatments, but some decrease was found in stored samples (especially soluble solid in fumigated samples) for 8 months under room temperature. Total sugar content was influenced by storage time rather than both treatments. Immediately after treatments, reducing sugar content was significantly reduced in the samples including pericarp when exposed to fumigants (p<0.05), while an apparent decrease was observed in the stored samples including seeds with negligible differences among treatment groups. The electron donating ability (EDA) of the extracts was high in the order of pericarp, whole pepper, powdered pepper and seeds, which was reduced during storage for 8 months particularly in the samples containing seeds. The EDA of irradiated samples during storage was equal to that of the control sample, whereas that of fumigated samples was relatively low (p<0.05).