• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.211-214
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• 1999

To acknowledge the differences in soil physical properties of cultivated land derived from major parent rocks in Yeong-nam areas, we investigated Riley's projection sphericity(one of the morphological properties) of sand and made up Soil Moisture Characteristics Curve(SMCC). The averages in Riley s projection sphericity range from 0.63 to 0.67 in soils derived from Sedimentary rocks than 0.56 to 0.61 in soils derived from igneous rocks. In case of soils derived from igneous rocks, the Riley's projection sphericity is lower as the particle size get to be smaller. The differences of SMCC were larger in the fine loamy soils than in coarse loamy soils. The moisture retention was higher in the soils derived from Sedimentary rocks than in the soils derived from Igneous rocks. After we transformed the water retention into dimensionless scale value by available water ratio, the SMCC was nearly unchangeable in the tested soils except for fine loamy soils derived from Sedimentary rock, but was not correlated with soil texture or parent rocks.

• Food Science and Preservation
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• v.4 no.3
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• pp.265-270
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• 1997

Effect of modified atmosphere packaging conditions on quality changes of dry jujube was investigated. Dry jujubes with moisture content of 26.7% were packaged in PET/Al/PE film pouches with modified atmospheres. The tested packages include those with normal air, vacuum, CO2 flushing, N2 flushing and O2 scavenger. Packages were stored at 25$^{\circ}C$ for 6 months, during which ascorbic acid concentration, browning level, titratable acidity and surface color were measured. Generally modified atmosphere packages could improve quality retention of dry jujubes except that vacuum package resulted in large surface color change. CO2-flushed package showed the best quality retention of high ascorbic acid content and low browning during 112 days, but caused high amounts of ascorbic acid destruction and browning in longer storage. In all the modified atmosphere packages titratable acidity reached a maximum followed by decline and subsequent rise, while it increased linearly with time in normal air package. Considering ascorbic acid retention browning level and surface color changes during 112 days, the packages of CO2 flushing and N2 flushing were better than others.

• KSBB Journal
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• v.30 no.3
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• pp.97-102
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• 2015

This study aimed to evaluate the potential plantgrowth promoting effects of potassium polyacrylate, a superabsorbent polymer, and Bacillus sp. SH1RP8, a family of plant-growth-promoting bacteria. Potassium polyacrylate was selected as the polymer for use due to its high molecular weight and its ability to retain and continuously supply moisture. Plant-growth-promoting rhizobacteria (PGPR) were isolated from the soil and applied to plants growing in dry environments, such as saline conditions. The moisture absorption and retention abilities of potassium polyacrylate were evaluated at a high temperature ($50^{\circ}C$) and in a dry condition, during which time the polymer showed a water retention potential of 19606.07% after 29 days. To overcome the reaming problem in the soil environment, natural polymers (such as cellulose) were mixed with the potassium acrylate. The shoot growths of Peucedanum japonicum Thunb and Arundo donax were significantly enhanced when treated with the mixture of the isolated rhizosphere bacterium SH1RP8 and potassium polyacrylate (63.5 and 124.3%, respectively).

• Food Science and Biotechnology
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• v.16 no.2
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• pp.187-192
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• 2007

The objectives of this study were to examine changes in the color and antioxidant compounds of paprika powder under various conditions, as well as to establish the suitable conditions for drying and storage. Paprika was dried using the following methods: freeze-drying, vacuum drying, far infrared-ray drying, and hot-air drying. Measurements of the moisture content, color pigments, and antioxidant compounds (total carotenoids, capsanthin, ascorbic acid, and total polyphenols) were completed during 120 days of storage at 4 and $30^{\circ}C$. We found that drying methods, storage temperatures, and packaging materials affected the American Spice Trade Association (ASTA) and Hunter color values, as well as the antioxidant content of paprika powder. There was a high correlation (r=0.87, p<0.01) between the ASTA color and the $a^*/b^*$ value. The loss of red color was closely related to the reduction of moisture content (r=0.81, p<0.01) during storage. Drying paprika with a low temperature in the absence of air resulted in better retention of the carotenoids and ascorbic acid. Also, as the retention of the carotenoids and ascorbic acid increased, the stability of the red pigment increased. Freeze-drying was found to be the most suitable drying method for the stability of the antioxidant compounds and red pigment.

• The Korean Journal of Community Living Science
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• v.25 no.2
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• pp.261-269
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• 2014

This study evaluates the nutritional retention factors influencing beef based on different cuts and boiling. Two cuts (brisket and shin foreshank) were prepared from beef and used in this experiment. Boiling methods were applied to each cut. The fat content of the boiled shin foreshank cut (236.43%) exceeded that of the brisket cut (142.38%). The moisture content of the boiled brisket cut (47.68%) was lower than that of the shin foreshank cut (49.54%). The sodium content of the boiled shin foreshank cut (47.89%) exceeded that of the brisket cut (37.30%). The potassium content of the boiled brisket cut (41.90%) exceeded that of the shin foreshank cut (39.63%). The calcium content of the boiled brisket cut (48.43%) was lower than that off the shin foreshank cut (71.34%). The phosphorus content of the boiled brisket cut (58.09%) exceeded that of the shin foreshank cut (57.24%). The iron content of the boiled brisket cut (72.72%) was lower than that of the shin foreshank cut (87.29%). Nutritional retention factors represent output data on cooking methods with a yield (%) for each item.

• Journal of the Korean Wood Science and Technology
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• v.18 no.2
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• pp.36-48
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• 1990

This experiment was carried out to improve the quality of high absorbent polymer which has excellent absorptivity and water retention compared to pulp and absorption sheet, through absorption characteristics-absorptive power, water retention, absorption rate, gel strength, pH, particle size, and moisture content. - of six polymers, namely, anionic polyacrylamide, cationic polyacrylamide, polyacrylic, acid polyvinyle alcohol 500, and 1500, and a-cellulose. and to examine the possibility of substitution of amide groups for carboxyl group and/or hydroxyl group which were commercial high absorbent polymer by comparing the absorption characteristics of the polymers. Polyacrylamide has high absorptive power and water retention, but has low gel strength and poor absorption rate. The rest of polymers were similiar to ${\alpha}$-cellulose in every respect. Thus, polyacrylamides could be replaced with polyacrylic acid and polyvinyl alcohol which are presently a high absorbent polymers. In comparing the absorption characteristics and the absorptive power of the polymers-anionic polyacrylamide, cationic polyacrylamide, polyacrylic acid, polyvinyle alcohol. a-cellulose-the absorptive power was in inverse proportion to the gel strength and absorption rates, affected by the particle size and pH change.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.810-817
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• 2015

This study was conducted to evaluate the pressure treatment characteristics of yellow poplar skin timber with ACQ-2, CUAZ-3, and CuHDO-1. The effect of moisture content (MC) on treatability was investigated, and fixation characteristics of copper-based preservatives were also evaluated. Sapwood of yellow poplar, which was dried below 50 percent MC, was fully penetrated with preservatives, and minimum requirement of preservative retention for the hazard class H3 was achieved. Through measuring retention gradient in yellow poplar sapwood, it was confirmed that minimum requirement of preservative retention for the hazard class H3 was achieved in the assay zone from the surface to 15 mm-depth when the specimens were dried below 30 percent MC. Yellow poplar heartwood did not meet the minimum requirement of penetration and retention for the hazard class H3 over the range of pretreatment MCs tested. The fixation rate of copper was much faster under drying condition compared with nondrying condition; more than 90% of copper were fixed in 3 weeks at $21^{\circ}C$ under drying conditions.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.133-138
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• 2001

In this paper, we have investigated the drying characteristics of waste sludge in a rotary dryer equipped with disintegration device. The sludge samples($moisture\;contents\;:\;70{\sim}85%\;W.B.$) used in the experiment were mainly a soybean and an alcohol fermentation sludges in food industry, or sewage sludge. It was studied by measuring the change of moisture contents that the shaft speed($operating\;range\;:\;100{\sim}250rpm$) affected on the drying rate and the particle size distribution of the dried solid. The dried granular products of the diameter of 1 to 5mm are obtained from sludge materials. In the results, as the increased of shaft speed, the particle size and the moisture contents of dried solid was decreased, and the retention time was increased.

• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.60-69
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• 2016

In this study, we estimated root zone soil moisture dynamics using remotely sensed (RS) data. A soil moisture data assimilation scheme was used to derive the soil and root parameters from MODerate resolution Imaging Spectroradiometer (MODIS) data. Based on the estimated soil/root parameters and weather forcings, soil moisture dynamics were simulated at spatio-temporal scales based on a hydrological model. For calibration/validation, the Little Washita (LW13) in Oklahoma and Chungmi-cheon/Seolma-cheon sites were selected. The derived water retention curves matched the observations at LW 13. Also, the simulated soil moisture dynamics at these sites was in agreement with the Time Domain Reflectrometry (TDR)-based measurements. To test the applicability of this approach at ungauged regions, the soil/root parameters at the pixel where the Seolma-cheon site is located were derived from the calibrated MODIS-based (Chungmi-cheon) soil moisture data. Then, the simulated soil moisture was validated using the measurements at the Seolma-cheon site. The results were slightly overestimated compared to the measurements, but these findings support the applicability of this proposed approach in ungauged regions with predictable uncertainties. These findings showed the potential of this approach in Korea. Thus, this proposed approach can be used to assess root zone soil moisture dynamics at spatio-temporal scales across Korea, which comprises mountainous regions with dense forest.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.784-791
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• 2015

Polyethylene glycol (PEG) impregnation prevents a red pine disk from cross-sectional checking during drying. Percentage of PEG Retention (PPR) was measured by the experimental methods of aceton extraction and moisture conditioning in a saturated salt solution and the effect of acetylation on PEG impregnated wood was investigated. PPRs of the kiln-dried specimens were much higher than those of the air-dried by at least four times and within the kiln-dried specimens those of the sapwood were higher that those of the heartwood by two times. These results were confirmed by the moisture conditioning experiment. Acetylation increased the weights of the kiln-dried specimens much less than those of the air-dried. It was revealed that acetic anhydride solution eluted PEG-1000 in the specimens. It is concluded that kiln-drying is more effective than air-drying for the increase of PPR and that acetylation eliminates the difference between the kiln- and air-dried specimens.