• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.223-230
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• 2017

The purposes of this study were to produce polysaccharides from red pepper stems using different extraction methods and evaluate their chemical composition, in vitro biological capacities, and rheological properties. Two polysaccharides were extracted from red pepper stems using an autoclave and alkali treatments, and the extracts were named PAU and PAL, respectively. The contents of total phenolics and flavonoids were significantly higher in PAU than those in PAL. PAU exhibited greater scavenging activities on 2,2-diphenyl-1-picrylhydrazyl radicals, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radicals, superoxide radicals, and nitrite compared to PAL, suggesting that PAU served as better antioxidants. Similarly, in vitro inhibitory abilities against carbohydrate hydrolyzing enzymes of PAU were higher than those of PAL. Steady shear rheological analysis demonstrated that PAU showed higher psuedoplastic shear-thinning behavior compared to PAL. Based on the results from dynamic shear rheological properties, it was found that both samples had predominantly viscous behavior rather than elastic behavior.

• Applied Biological Chemistry
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• v.27 no.4
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• pp.245-251
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• 1984

Physicochemical properties of arrowroot starch were investigated. The starch had blue value of 0.397, alkali number of 10.1 and amylose content of 22.0%. The starch was practically insoluble in water up to $55^{\circ}C$. X-ray diffraction was C pattern, but was close to A pattern. The alkali number, X-ray pattern and viscogram of the starch and retrogadation rate of the starch gels indicated that the properties of the arrow root starch were close to those of cereal starches.

• Macromolecular Research
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• v.17 no.12
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• pp.950-955
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• 2009

The physical and rheological properties of thermoplasticized irradiation-crosslinked polyethylene foam using supercritical methanol treatment were investigated by GPC, FTIR, DSC, WAXS, DMTA and UDS. The polyethylene foam was selectively decrosslinked into thermoplasticized polyethylene in an appropriate supercritical methanol condition without any undesirable side reactions such as oxidation and disproportionation. The thermoplasticization was promoted with increasing reaction temperature to reach completion above $380^{\circ}C$. The supercritical reaction condition affected the crystallization behavior, and mechanical and rheological properties of the decrosslinked polyethylene foam, but not its crystallographic structure or crystallinity.

• ETRI Journal
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• v.38 no.2
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• pp.252-259
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• 2016

Di(1-aminopyrene)quinone (DAQ) as a quinone-containing conducting additive is synthesized from a solution reaction of 1-aminopyrene and hydroquinone. To utilize the conductive property of DAQ and its compatibility with activated carbon, a composite electrode for a supercapacitor is also prepared by blending activated carbon and DAQ (3:1 w/w), and its supercapacitive properties are characterized based on the cyclic voltammetry and galvanostatic charge/discharge. As a result, the composite electrode adopting DAQ exhibits superior electrochemical properties, such as a higher specific capacitance of up to $160F{\cdot}g^{-1}$ at $100mV{\cdot}s^{-1}$, an excellent high-rate capability of up to $1,000mV{\cdot}s^{-1}$, and a higher cycling stability with a capacitance retention ratio of 82% for the 1,000th cycle.

• Rapid Communication in Photoscience
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• v.2 no.2
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• pp.52-55
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• 2013

Proteorhodopsin (PR) is a photoinduced proton pump found abundantly in ocean and fresh water habitat, and has an important role in photoenergy conversion to bioenergy in the living cells. Numerous sequences that encode PR protein variants were discovered by environmental genome sequencing and they indicated the high sequence similarity. A new-type of PR (YS-PR) which had been discovered from the surface of Yellow Sea was found to have only 5 amino acid differences from the previously known green-light absorbing PR (GPR) protein, but showed different photochemical properties. This YS-PR showed a 10 nm red-shifted absorption maximum, when compared with GPR. It also showed slower photocycling rate than GPR. However, the photoconversion rate of YS-PR was fast enough to pump protons. Four different amino acids out of 5 were similar to Blue-light absorbing PR (BPR), suggesting that those residues might be responsible for the observed spectral and photoconverting properties.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.83-93
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• 2000

This study was carried out to improve the physico-mechanical properties of board products by applying the technique of high frequency heating, and find out the optimum conditions of high frequency heating, compared with the technique of hot platen heating. The possibility of isocyanate resin application to board production was also considered to solve the problem of free formaldehyde emission from urea resin which is generally used in wood industry. For this study, 30 mm thick MDP (medium density fiberboard) with isocyanate resin were manufactured by the techniques of hot platen heating, high frequency heating and the combination techniques of both heating methods, and compared in several point of views.

• Journal of Life Science
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• v.9 no.1
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• pp.64-68
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• 1999

The properties of purified intracellular adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4) of Nocardioides sp. J-326TK isolated from soil have been studied. The enzyme deaminated adenosine and 2`-deoxyadenosine and the respective {TEX}$K_{M}${/TEX} values were 4.0×{TEX}$10^{-4}${/TEX} M and 5.0× {TEX}$10^{-4}${/TEX} M, but the enzyme was not active on 8-bromoadenosine, 6-methylaminopurine riboside, ATP, ADP, 2`-AMP, 3`-AMP, 5`-AMP, dAMP, cAMP, NAD, FAD, NADP and adenine. The enzyme activity was strongly inhibited by the addition of {TEX}$Hg^{2+}${/TEX} and {TEX}$Ag^{+}${/TEX}, {TEX}$Cu^{2+}${/TEX}, {TEX}$Co^{2+}${/TEX} and {TEX}$Mn^{2+}${/TEX} also inhibited the activity but much less extent. The effect of alkyl reagents, metal chelating reagents and certain other compounds on the enzyme activity were also examined. No reagent activated the enzyme. On the contrary, the enzyme reaction was slightly inhibited by o-phenanthroline and 6-benzyladenosine.

• Journal of Applied Biological Chemistry
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• v.49 no.2
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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 Journal of Agricultural Science
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• v.23 no.2
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• pp.233-241
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• 1996

The mechanical properties of biological materials depend on numerous factors. The majority of these relationships are still unknown today, especially with regard to their quantitative characteristics. The reason is that biological materials constitute biomechanical systems of very complex construction, whose behavior cannot be characterized by simple physical constants, as for example can that of engineering materials. The objectives of this investigation were to determine the compression creep and recovery properties of rice stalks at various levels of applied load The compression creep and recovery behavior of the rice stalk could be predicted precisely by rheological model which approached closely to the measured values. But the coefficients of the Burgers recovery model were different from those of the creep model. The Steady state creep behavior occurred at the higher level of force and the logarithmic creep behavior occurred at the lower level of force. The mechanical model being expected the creep behavior in relation with the level of applied load, which was well explained that the rice stalk might be visco-elastic material.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.35-40
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• 1994

A probe was designed to study the relationship of photon flux path and layered properties of bilogical tissue. The result shows that different wavelengths have different flux path and maximum reflectance position with separation. The source-detector separations on maximum reflectance of IR and GR were 7.5 mm and 2.5 mmm each other and layered properties of tissue can be discriminated bye the change of S-D separation using designed probe.