• Food Science and Biotechnology
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• v.18 no.3
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• pp.604-609
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• 2009

The antioxidative activities of the water solution of crude extract from edible mushroom enokitake Flammulina velutipes were compared with those of ascorbic acid and ascorbic acid 6-palmitate in oil-in-water (O/W) emulsions of cod liver oil. Oxidation of the emulsions was carried out at 40 and $50^{\circ}C$ in the dark. The antioxidant activities were measured by in vitro assay against oxygen uptake, 2-thiobarbituric acid value, hydroperoxide formation of the oils. Also, residual docosahexaenoic acid content was measured as indices of lipid oxidation. The cod liver oil in O/W emulsions with added enokitake crude extract (ECE) was significantly more stable against lipid oxidation than the control emulsions without the extract in terms of any oxidation indices used. Moreover, ECE provided remarkable antioxidative properties to eicosapentaenoic acid ethyl ester in emulsion system. These observations demonstrate that F. velutipes can be used as a natural antioxidant, which effectively prevents oxidation of polyunsaturated oils in emulsion system.

• Membrane and Water Treatment
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• v.10 no.4
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• pp.265-275
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• 2019

This study aimed to develop a compact partial nitritation step by forming granules with high Ammonia-Oxidizing Bacteria (AOB) fraction using the Air-lift Granulation Reactor (AGR) and to evaluate the feasibility of treating reject water with high ammonium content by combination with the Anammox process. The partial nitritation using AGR was achieved at high nitrogen loading rate ($2.25{\pm}0.05kg\;N\;m-3\;d^{-1}$). The important factors for successful partial nitritation at high nitrogen loading rate were relatively high pH (7.5~8), resulting in high free ammonia concentration ($1{\sim}10mg\;FA\;L^{-1}$) and highly enriched AOB granules accounting for 25% of the total bacteria population in the reactor. After the establishment of stable partial nitritation, an effluent $NO_2{^-}-N/NH_4{^+}-N$ ratio of $1.2{\pm}0.05$ was achieved, which was then fed into the Anammox reactor. A high nitrogen removal rate of $2.0k\; N\;m^{-3}\;d^{-1}$ was successfully achieved in the Anammox reactor. By controlling the nitrogen loading rate at the partial nitritation using AGR, the influent concentration ratio ($NO_2{^-}-N/NH_4{^+}-N=1.2{\pm}0.05$) required for the Anammox was controlled, thereby minimizing the inhibition effect of residual nitrite.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1174-1179
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• 2009

An experiment was conducted to study the effect of post-hatch feed deprivation on yolk sac utilization andsubsequent performance of young broiler chickens (280) up to 35 days of age. The experimental treatments included access to feed at 8 h intervals after hatch, up to 48 h (0, 8, 16, 24, 32, 40 or 48 h). Water was offered ad libitum to all the groups immediately after placement. Results indicated that chicks with access to feed immediately after hatch used up the residual yolk more quickly. Access to feed between 8-24 h post-hatch, supported faster utilization of residual yolk compared to those chicks that remained unfed for 40-48 h (p<0.05). Further, deprivation of feed up to 24 h did not alter the lipid and protein contents in residual yolk, but fasting of chicks beyond 24 h (32, 40 and 48 h) led to retention of higher lipid and lower protein content in the yolk sac (p<0.05). At 7 days of age, the weights of proventiculus and gizzard were not affected by feed deprivation up to 48 h. However, the liver, pancreas and jejunum recorded significantly (p<0.05) heavier weights in chicks that were fed during the initial 24 h period compared to delayed feeding (32-48 h). Chicks fed within 24 h after hatch gained significantly (p<0.05) higher weight at 5 weeks of age than those that received feed between 32 and 48 h. Feed deprivation for 48 h was more detrimental to growth than 24-40 h. This study revealed the significance of early posthatch feeding (<24 h) on faster utilization of yolk sac nutrients and optimum development of intestines and organs, culminating in improved weight gain (>10.5%) of broilers at 5 weeks of age.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.24-32
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• 1998

This study examined the effects of recycling on chemical pulp fibers from multiple recycles. Firstly, water-pretreated alkaline photocopy paper was disintegrated by TAPPI standard disintegrator at room temperature. After dewatering, this pulp was dried in oven at $80^{\circ}C$ for 24hrs. A sequence of wetting, disintegrating and drying was one recycling cycle and this cyclic treatment was repeated from zero to five times. The recycled handsheet dropped to 90% of the original brightness after five cycles, and lost the most brightness in the first two cycles. However, it had a gain of 10% in opacity after five cycles. And, in this study, the method for determining residual ink(toner) content in recycled handsheets were estabilished by means of SEM-EDX and atomic absorptive photometer. The change of residual ink percentage on recycled paper showed the effect of recycling numbers on deinkability of waste paper. A slight decrease in deinkability was noted for the recycled handsheets, which may be due to the change of fiber surface free energy connected with fiber swelling.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.117-126
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• 2011

Based on thermodynamics, the mathematical framework governing the hydro-mechanical behavior of partially saturated soil is derived by using balance equations, and the numerical analysis through implementation of various effective stress definitions is performed. Effective stress on partially saturated soil describes the soil strength which is presented by the relationship between water content and soil suction. For the estimation of hydro-mechanical behavior on partially saturated soil, effective stress parameter ${\chi}$ defined from various literatures is especially analyzed to understand the conditions of constitutive equations regarding residual saturation and displacement of soil. As a result, effective stress parameter ${\chi}$ has an influence on the variation of matric suction in soil with an external load and seepage. However it was found that the effect of each parameter ${\chi}$ varies with residual degree of saturation, and that of each parameter ${\chi}$ decreased with decrease in displacement of soil caused by an external load.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.155-163
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• 2007

High Strength Concrete (HSC) has weakness that in a fire, it is spalled and brittles. The phenomenon of spalling is made by water vapor's (resulting from evaporation in the material at over $100{^{\circ}C}$)' being confined in watertight concrete. As the concrete strength increases, the degree of damage caused by the spalling becomes more serious because of the permeability. It is reported that the polypropylene(PP) fiber has an important role in protecting concrete from spalling and the optimum dosage of PP fiber is 0.2%. This study was conducted on the nonreinforced concrete specimens. The high-temperature behavior of high-strength reinforced concrete columns with various concrete strength and various dosage of PP fibers was investigated in this study. The results show that the ratio of unstressed residual strength of columns increases as the concrete strength increases and the ratio of unstressed residual strength of columns increases as the dosage of PP fiber increases from 0% to 0.2%, however, the effect of fiber dosage on residual strength of column barely changes above 0.2%.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.321-330
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• 2011

Recently, the effects of high temperature and fiber content on the residual mechnical properties of high-strength concrete were experimentally investigated. In this paper, residual mechanical properties of concrete with water to cement (w/c) ratios of 0.55, 0.42 and 0.35 exposed to high temperature are compared with those obtained in fiber reinforced concrete with similar characteristics ranging from 0.05% to 0.20% polypropylene (PP) fiber volume percentage. Also, factors including pre-load levels of 20% and 40% of the maximum load at room temperature are considered. Outbreak time, thermal strain, length change, and mass loss were tested to determine compressive strength, modulus of elasticity, and energy absorption capacity. From the results, in order to prevent the explosive spalling of 50 MPa grade concretes exposed to high temperature, more than 0.05 vol. % of PP fibers is needed. Also, the cross-sectional area of PP fiber can influence the residual mechanical properties and spalling tendency of fiber reinforced concrete exposed to high temperature. Especially, the external loading increases not only the residual mechanical properties of concrete but also the risk of spalling and brittle failure tendency.

• Analytical Science and Technology
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• v.30 no.5
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• pp.226-233
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• 2017

In general, quantitative chemical analysis in various areas including food, the environment, in vitro diagnostics, etc., requires traceability in order to increase the reliability of the measurements. Measurement traceability is a property of an unbroken chain of comparisons relating an instrument's measurements to SI units. Purity analysis is the first process for establishing traceability to SI units in chemical measurements. The purpose of this study is to develop and validate a method of purity assignment for establishing the traceability of $17{\beta}$-estradiol measurements in an in vitro diagnostics field. The establishment of this method is very important as it can be applied to the development of CRM and to the analysis of the purity of other hormones. The method of assignment of the purity of $17{\beta}$-estradiol was developed using the mass balance method and was validated through participation in an International comparison. In the mass balance method, impurities are categorized into four classes as follows: total related structure impurities, water, residual organic solvents, and nonvolatiles/inorganics. In this study, total related structure impurities were characterized by a gas chromatography-flame ionization detector (GC-FID) and a high-performance liquid chromatography-ultraviolet (HPLC-UV) detector, water content was determined by a Karl-Fisher coulometer, and total residual solvents and nonvolatiles/inorganics were checked simultaneously by thermogravimetric analysis (TGA). The purity of the $17{\beta}$-estradiol was 985.6 mg/g and the expanded uncertainty was 2.1 mg/g at 95% confidence. The developed method can be applied to the development of certified reference materials, which play a critical role in traceability.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.300-305
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• 2007

The purpose of this study is to examine changes in the residues of procymidone and diazinon in Chwinamul, pepper leaves, and young radish according to drying method. When the three vegetables were dried at room with air stream, the residues of procymidone and diazinon increased, but after being adjusted to reflect the decrease in water content of the vegetables, the residues declined by 10 to 83 percent. When they were dried in a oven, the residues of the pesticides in the vegetables also increased, but after being adjusted to reflect the drop in the water content, the residues decreased by 44 to 71 percent. According to the results, the residues of the pesticides mostly decreased after being adjusted to reflect the drop in the water content of the dried vegetables. Therefore, when judging dried agricultural products not only the decreased water content of dried vegetables but also other factors that affect pesticide residues during the drying process should be considered. This raises the need for additional research on such factors.

• Culinary science and hospitality research
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• v.23 no.8
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• pp.153-162
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• 2017

Bacillus coagulans was added as probiotics in instant coffee with microground roasted coffee which is recently rising premium coffee and the instant coffee (ProBio coffee) was compared with 3 commercial instant coffees with microground roasted coffee in quality characteristics to understand the competitiveness of ProBio coffee. In sensory evaluation, ProBio coffee had inferior aroma intensity and overall acceptance compared with control group (brewed coffee) (p<0.05) but it had equal quality or more compared with 3 commercials. Total polyphenol content, chlorogenic acid content, DPPH free radical scavenging activity and caffeine content were $110.72{\pm}1.99mg/g$, $2,700{\pm}20mg/g$, $146.22{\pm}3.62TEAC\;mg/g$, $28.1{\pm}3.2ppm$ respectively. In general quality characteristics, water content, solubility, particle size and particle strength of ProBio coffee were similar to general instant coffee but had darker color than it. In safety assessment, acrylamide content was $502{\pm}10ppb$, and residual pesticides and ochratoxin A were not detected. Over 70% of B. coagulans were maintained in 4 months of storage and 16 months of shelf life was predicted in ProBio coffee by $Q_{10}$ model. Therefore, ProBio coffee was confirmed to have a sufficient product competiveness compared with 3 commercials.