• Journal of Sensor Science and Technology
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• v.7 no.1
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• pp.1-8
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• 1998

We have simulated the operating characteristics of the magnetotransistor(MAGFET) by the finite element method and suggested the optimum design conditions to get a maximum sensitivity, The magnetotransistor has been fabricated by CMOS standard processing according to the suggested design conditions and investigated its electromagnetic characteristics. The sensitivity of the magnetotransistor depends on the ratio of width(W) to length(L) of active area rather than its size, and has a maximum when W/L = 1. The relative sensitivity of a fabricated magnetotransistor was 2.53 %/T.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.1-6
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• 2006

Through the application of a microwave-assisted extraction, the aim of study was to investigate the extraction conditions for the total yield, electron donating ability, total polyphenol contents and nitrite scavenging effect from Pleurotus eryngii. This experiment was conducted under the following extraction conditions: the microwave power (60, 90, 120 W), sample to solvent ratio (1:50, 1:20, 1:10), extraction time (1, 5, 10, 15 mins), and extractant like water, $50\%$ EtOH and $99\%$ EtOH. During the increase of microwave power ranging from 60 to 120 W, the maximized effective components were obtained when the microwave power was set at 60 W. By decreasing the ratio down to 1:10 (g/mL), the extraction of effective components but not total yield was the highest at 1:10 (g/mL). As going up to 15 min, the maximum extraction of effective components was achieved at 1 min for the extraction time and was little affected at over 5 min. In conclusion, the most appropriate conditions for the extraction of effective compounds from Pleurotus eryngii were as follows: the microwave power at 60 W, 1:10 of the sample to solvent ratio, extraction time at 1 min and water as the extractant.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.2
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• pp.126-137
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• 2003

The feasibility study of UV-disinfection system was performed for disinfection of effluent from wastewater treatment plant. Three low-pressure UV lamps of 17, 25, and 41 W were examined with various flow rates. Low-pressure UV lamps of 17W were examined with various turbidity, DOM (dissolved organic matter), and SS (suspended solid). The pilot plant was a flow-through type UV-disinfection system, and the range of exposure time varied from 5 to 40 seconds, turbidity from 0 to 40 NTU, DOM from 0 to 30 mg/L, and SS from 10 to 40 mg/L. The 41W lamp demonstrated complete disinfection showing no survival ratio in all the experimental conditions, and generally 17W and 25W lamps also showed high removal ratio over 97%. For the same UV dose (UV intensity times exposure time), high intensity-short exposure conditions showed better disinfection efficiency than low intensity-long exposure conditions. While the effects of turbidity and DOM were not apparent, the effects of SS was significant on the disinfection efficiency which indicates that SS control before UV-disinfection appears to be necessary to increase removal efficiency. Considering characteristics of effluent from existing wastewater treatment plants, cost-effectiveness, stable performance, and minimum maintenance, the flow-through type UV-disinfection system with high intensity and low-pressure lamps was thought to be a competitive disinfection system for wastewater reclamation.

• Food Science and Preservation
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• v.8 no.3
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• pp.326-330
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• 2001

The characteristics of used wine yeast strains were as follows, S6U showed low fermentation speed than those of other yeast strains, but this strain fermented completely later. The wine fermented by W-3 was very low contents of total acid, 0.75% and the ones fermented by UCD530 and AC- contained much extract, 3.26 mg/L and 3.22 mg/L respectively. The wine fermented by CEG and CS2 were predominant in yellowness, and EC1118 produced large amount of acetaldehyde, 49.9 mg/L than those of other strains. EC1118 and CY3079 displayed low methylene blue dyeing ratio, below 15%, meaning high alcohol tolerance yeast. UCD530 produced extremely high contents of glycerol, succinate and lactate compared with other strains. These properties revealed that UCD530 was a typical Saccharomyces bayanus species. The main organic acids produced by wine yeasts were pyruvate, lactate, succinate and acetate. The concentration of acetate in experimental wine could be divided into two parts, one group had concentration below 170 mg/L (UCD530, EC1118, AC-, CY3079, W-3), and the other had concentration up to 350 mg/L (S6U, CEG, CS2).

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.62-65
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• 2010

This study was carried out to estimate the size and exine pattern of pollen grains in seven species of the genus Lilium by using scanning electron microscope. Exine of pollen grains, which were all monad, took the prolate forms with a pollen aperture. However, there were various L/W ratio between length (L) and width (W) of pollen grains among selected Lilium species. The pollen of L. distichum was oblong shape which had the highest L/W ratio of 2.59. On the other hand, that of L. concolor var. partheneion was broadly elliptical shape close to circle which had the lowest L/W ratio of 1.82. The surface patterns of exine were reticulate in all Lilium species that have showed diverse forms in their lumina. Pollen length and width in L. lancifolium had the greatest value, 115.90 and $46.54{\mu}m$, respectively, in comparison with those of L. tsingtauense, 70.33 and $38.72{\mu}m$, respectively. Except L. distichum and L. leichtlinii var. maximowiczii which had a similar pollen length within standard errors, the others in Lilium species showed different sizes, respectively. Therefore, these results indicated that pollen length could be a better standard for the classification of Lilium species than exine surface patterns or pollen dissection area.

• Journal of Convergence for Information Technology
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• v.11 no.6
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• pp.188-197
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• 2021

In this study, the optimal conditions for hair dyeing using sappan wood (Caesalpinia sappan L.) powder were determined, and then the effect of chitosan treatment on the hair dyeing properties of sappan wood powder was investigated. Treatment of sappan wood powder and water with the ratio of 1:3 (w/w) at 40℃ for 60 minutes was found to be the most effective to hair dyeing. In addition, the pretreatment of low molecular weight (~30 kDa) chitosan at a concentration of 1% (w/w) prior to treatment with sappan wood powder effectively improved and maintained the hair dyeing properties of sappan wood. In conclusion, the low molecular weight chitosan is considered to be of great help as a mordant in improving the dyeing efficiency and retention of sappan wood powder in hair dyeing.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.673-679
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• 2004

A microbial cryoprotectant formulation using a W/O/W multiple emulsion system was developed. The psychrotolerant microorganism, B4, isolated from soil in South Korea, was observed by the drop freezing method, in which the microorganism sample inhibited ice nucleation activity. The antifreeze activity was eliminated when the microorganism sample was treated with protease, indicating that the antifreeze activity was due to the presence of antifreeze protein. The result of the l6S rDNA sequencing indicated the B4 strain was most closely related to a species of the genus Bacillus. Culture broth of B4 strain (Bacillus sp.) and rapeseed oil containing 1 % polyglycerine polyricinolate (PGPR) were used as core and wall material, respectively. The most stable W/O emulsion was prepared at a core/oil ratio of 1:2. The highest W/O/W emulsion stability was achieved when the primary emulsion to external aqueous phase containing 0.5% caster oil polyoxyethylene ether $(COG25^{TM})$ ratio was 1:1. Microcrystalline cellulose showed better W/O/W emulsion stability than other polymer types. The viability of cells in a W/O/W emulsion was higher than free cells during storage at $37^\circ{C}$. An acidic pH and UV exposure decreased the viability of free cells, but cells in W/O/W emulsion were more stable under these conditions.

• Membrane and Water Treatment
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• v.15 no.1
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• pp.11-19
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• 2024

This study presents the characteristics of growth and morphology of Anabaena sp., a representative filamentous cyanobacterium, depending on temperature variation from 10 to 30 ℃. Both the filament density (or number) and its length of Anabaena were highly affected by temperature, as well as growth stage. Rapid growth at a higher temperature led to an increase in Anabaena filament density, as well as optical density at 680 nm (OD₆₈₀). However, the number of vegetative cells within a single filament of Anabaena grown at 30 ℃ was smaller than those grown at lower temperatures, due to the intercalary division of the filament. Of the three different cells comprising a single Anabaena filament, the vegetative cell marginally affects the growth of Anabaena. The main dimensions of the vegetative cell, i.e., length and width, depend on the temperature and growth stage. The length-to-width (L/W) ratios of vegetative cells and akinetes were relatively consistent regardless of the temperature. However, in vegetative cells with dichotomous growth, the L/W ratio shows clear differences depending on their growth stage. It has been demonstrated that the L/W ratio could be used as an indicator to indirectly predict the growth stage of on-sit Anabaena samples.

• Applied Chemistry for Engineering
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• v.34 no.3
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• pp.299-306
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• 2023

In this study, the O/W emulsification processes with the natural surfactants that were extracted from Medicago sativa L. and Sapindus saponaria L. as emulsifiers were optimized using the central composite design-response surface methodology (CCD-RSM). Herein, independent parameters were the amounts of mixed emulsifiers, the mixing ratio of natural emulsifiers (soapberry saponin/alfalfa saponin), and the emulsification time, whereas the reaction parameters were the emulsion stability index (ESI), mean droplet size (MDS), and antioxidant activity (DPPH radical scanvenging activity). Through basic experiments, the ranges of operation variables for the amount of mixed emulsifiers, the mixing ratio of natural emulsifiers, and the emulsification time were 12~14 wt%, 30~70%, and 20~30 min, respectively. The optimum operation variables deduced from CCD-RSM for the amount of mixed emulsifiers, the mixing ratio of natural emulsifiers, and the emulsification time were 13.2 wt%, 44.2%, and 25.8 min, respectively. Under these optimal conditions, the expected values of the ESI, MDS, and antioxidant activity were 88.7%, 815.5 nm, and 38.7%, respectively. And, the measured values of the ESI, MDS, and antioxidant activity were 90.6%, 830.2 nm, and 39.6%, respectively, and the average experimental error for validating the accuracy was about 2.1%. Therefore, it was possible to design an optimization process for evaluating the O/W emulsion process using CCD-RSM.

• Plant Resources
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• v.3 no.3
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• pp.226-232
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• 2000

The availability of enokitake cultural waste for Lentinus edodes cultivation was investigated, although hardwood sawdust has traditionally been used as a substrate for this fungus. Firstly, physiochemical characteristics of cultural waste were analysed. Secondly, mycelial growth characteristics and fruiting yields of L. edodes on waste treated in some methods were determined. Physiochemical characteristics of enokitake cultural waste showed that the millwaste complex was a little degraded by enokitake fungus and suggested the probability that most component lost by enokitake could be rice bran. Mycelia of L. edodes grew and fruited well on waste supplemented by fresh rice bran and Quercus sawdust although didn't on waste only. Mycelial growths of these fungi on waste were accelerated when supplemented by rice bran to the percent of 40(w/w) but decreased or suppressed at above ratios(30, 40%, w/w). Supplementations of oak sawdust at above 40%(w/w) of the waste and rice bran at 20%(w/w) of the sawdust allowed such a good mycelial growth as to be selected as a pertinent mixing ratio for fruiting medium. A fruiting yield on enokitake cultural waste supplemented by oak sawdust (at 40% of the waste, w/w) and rice bran (at 20% of the sawdust, w/w) was not inferior to that on oak sawdust supplemented by rice bran only (at 20% of the sawdust, w/w). These results indicated strongly the potentiality of enokitake cultural waste as raw materials for shiitake cultivating substrates.