• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.740-745
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• 2002

The current study was conducted to identify the differences in the rheological properties of Chlorella sp. powder cultured in a fermentor and in a pond-like environment. Cells. cultured in the same media were harvested and spray dried. The biomass yield from the fermentor culture was 4.7% (dry basis), while that from the pond was 4.3% (dry basis). Measurements of the loose bulk density, tapping test, Hausner's ratio, and compressibility test all revealed differences between the rheological properties of the Chlorella sp. from the two cultivation systems. Although both the fermentor and pond cultured Chlorella sp. showed the same angle of repose, the mean size of the cells was 2.26 $\mu\textrm{m}$ and 2.89 $\mu\textrm{m}$, respectively. The weight of the Chlorella sp. tablets cultured in the fermentor and pond was 0.663 g/tablet and 0.593 g/tablet, respectively, while the friability of the tablets was 21% and 41%, respectively. Observation by Transmission Electron Microscope (TEM) showed that the cell wall of the Chlorella sp. cultured in the fermentor was thinner and more spherical than that cultured in the pond, thereby providing the main characteristic rheological properties of the powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1320-1325
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• 2012

This study investigated the bulk properties of red pepper powders according to drying method and variety. Bulk density, compressive characteristics, irrecoverable work, dynamic angle, and stress relaxation were investigated. Loose bulk density ranged between 0.420 $g/cm^3$ for Cheongyang cultivar and 0.427 $g/cm^3$ for Hanbando cultivar by hot-air drying. The highest tapped bulk density was 0.586 $g/cm^3$ for Hanbando cultivar by far-infrared drying and the lowest value was 0.523 $g/cm^3$ for Hanbando cultivar by sun drying. Hausner ratio reached a maximum value of 1.370 for Hanbando cultivar by far-infrared drying. Compressibility ranged between 0.0016 for Cheongyang cultivar by sun drying and 0.0023 for Hanbando cultivar by far-infrared drying. Compression ratio reached a maximum value of 1.032 for Hanbando cultivar by hot-air drying. Dynamic angle of repose ranged between 37.47 and $42.97^{\circ}$. Irrecoverable work ranged between 76.0 and 81.7%. Relaxation reached a maximum value of 24.31% for Cheongyang cultivar by far-infrared drying.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.421-426
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• 2013

We evaluated physical properties such as density, compressive characteristics, irrecoverable work, and stress relaxation of red pepper powder with different particle sizes. The particle sizes showed a normal distribution in size, with a particle size of $150{\sim}600{\mu}m$ accounting for 70.95% of the particles in the Hanbando cultivar and 82.21% in the Cheongyang cultivar. Loose bulk density ranged between 0.34 and $0.45g/cm^3$, while tapped bulk density ranged between 0.43 and $0.56g/cm^3$. The Hausner ratio was highest (1.531) at a particle size below $150{\mu}m$ in the Cheongyang cultivar. The compressibility and compression ratios were 0.001351~0.004383 and 1.0062~1.0265, respectively. Irrecoverable work ranged between 69.16% and 90.24%. The $K_2$ value and stress relaxation characteristics were greatest (1.74 and 44.92%, respectively) at particle sizes of $300{\sim}425{\mu}m$ in the Cheongyang cultivar. The dynamic angle of repose was $32.84-49.84^{\circ}$. Overall, particle sizes below $150{\mu}m$ had the highest compactibility, cohesiveness, and transformation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.599-605
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• 2011

This study investigated the physical properties of red pepper powders according to cultivation area and variety. Values for density, compressive characteristics, dynamic angle, irrecoverable work, and stress relaxation were analysed. Loose bulk density ranged between 0.40 and 0.50 g/$cm^3$, and tapped bulk density ranged between 0.49 and 0.67 g/$cm^3$. The highest Hausner ratio was 1.369 for PRmanitta cultivated in Eumseong and the lowest value of was 0.194 for Buchon cultivated in Yeongyang. Compressibility ranged between 0.0046 and 0.0092. The highest compression ratio was 1.040 for Myeongjak cultivated in Suwon, and the lowest value was 1.007 for Buchon cultivated in Yeongyang. Dynamic angles ranged between 35.14 and $41.70^{\circ}$. The highest irrecoverable work value was 79.9% for PRmanitta cultivated in Eumseong and the lowest value was 67.9% for Nokgwang cultivated in Suwon. The greatest $k_2$ and relaxation values of stress relaxation characteristics were 1.56 and 42.03%, respectively, for Cheongyang cultivated in Yeongyang.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.1
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• pp.170-181
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• 1997

The purpose of this study was to determine the effect of knit structure and knit density (machine tightness factor) on the dimensional properties and K1-4 values of weft-knitted fabrics followed over eleven cycles of mechanical relaxation to provide the basic data for constructing weft-knitted fabrics for outwear with excellent dimensional stability The eighteenth weft-knitted fabrics were produced with different knit structure (1$\times$1 rib, half-cardigan rib, half-milano rib, interlock, single pique, crossmiss interlock) and machine tightness factor (loose, medium, tight) for this study. Dimensional properties such as width, lengh, area shrinkage and dimensional parameter (K) of eighteenth knitted fabrics including thickness and bulk property were measured. The results were as follows; 1. The dimensional behavior of the Ix1 rib and interlock in relaxation cycles was anisotropic, i.e., length shrinkage was usually associated with a width expansion, whereas the other weft-kntted fabrics which have tuck or miss loops in the knit structure behaved isotropically, i.e., length and width shrinkages were usually found. It was proposed that the difference in dimensional behavior between these structures was due to the dissimilar nonrelaxed geometrical shapes of the individual structural units forming these weft-knitted structures. The mechanical relaxation shrinkage of weft-knitted cotton fabrics was dependent on the tightness of construction. For a range of fabrics knitted on this study, an increase in fabric tightness caused a decrease in the length shrinkage of the fabric accompanied by an increase in its width shrinkage.

• Journal of Ginseng Research
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• v.26 no.2
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• pp.79-84
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• 2002

In this study, cell cracker method as a non-collision method was evaluated for the possibility in manufacturing red ginseng powder. In color value of red ginseng powder, the L values indicating brightness were 68.18 for hammer mill (group A) and 72.08 for cell cracker (group B). The a values (redness) and b values (yellowness) were 4.21 26.56 for group A and 5.73, 28.36 for group B, respectively. As an extraction time increased, the absorbances at 420 nm of water extract of both groups were increased. In the loose bulk density, tapped bulk density and volume reduction radio indication the of powder in group A were less than those in group B. In both groups, the angles of side of red ginseng powder were shown less value than the angles of side of the powder. These two angles in group A were lets than those in group B. In sensory evaluation, the touchness between both groups was, not observed significant difference. In the contrary, the color and flavor, main factors affecting the overall quality of red ginseng powder product of group B were shown superior to those of group A. The overall preference of group B was shown higher than that of group A.