• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.208-212
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• 1975

The study was conducted to determine the optimum conditions for keeping quality of shucked sea mussel, Mytilus edulis, during marketing under commercial handling. As quality factors, water holding capacity, pH, VBN and TMA content were measured. Water holding capacity was obviously affected by salt content of the sea mussel meat. Water was released at the salinity above $2.8\%$ and absorbed below the value. In case of distilled water added instead salt solution, $23.3\%$ weight was gained. Absorbing or releasing water of sea mussel meat was also influenced by temperature showing either water gain or loss was greater at, $3^{\circ}C\;than\;25^{\circ}C$. Osmotic quilibrium by salt between meat and liquor was held within 4 hours. The pH value of fresh sea mussle marked 6.0 which is somewhat lower when compared with that of other shellfishes, and it gradually decreased to 5.0 during storage. VBN contents of fresh muscle and shell liquor were $2.1mg\%$ and $1mg\%$ respectively. The sour odour began to be detectable with $5.0mg\%$ of VBN content. TMA in the sea mussel was not detected.

• Computers and Concrete
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• v.31 no.2
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• pp.97-110
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• 2023

This study investigates experimentally the impact of magnetized water (MW) on the fresh and hardened characteristics of concrete. Five types of MW are produced using magnetic fields of 1.4 and 1.6 Tesla for treating water with 100, 150, and 250 cycles. The concrete properties are assessed using the slump test, compressive strength test, scanning electron microscopy (SEM) analysis, energy dispersive X-ray analysis (EDX), and Fourier transform infrared spectrophotometry (FTIR). Furthermore, the chemical-physical characteristics of tap water (TW) and MW are evaluated. The results showed the magnetic field intensity has a significant impact on the magnetization effect; the best magnetizing conditions were found when TW was exposed successively to magnetic fields of 1.6 T and 1.4 T for 150 cycles. In addition, 150 MW cycles can be used to improve the compressive strength and workability of concrete by 40% and 17%, respectively. pH, total dissolved solids, and electrical conductivity improved by 15%, 17%, and 7%, respectively, when using MW. Additionally, MW can be used to enhance cement hydration chemical processes and made concrete's structure denser.

• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.129-146
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• 1998

Fatty acid compositions of seventy-two species of Korean fish muscle, 59 species of sea water fish and 13 species of fresh water fish, were studied. Polyunsaturated fatty acid (PUFA) was the richest fatty acid group in all fish samples, accounting for $38.0\pm10.3\%$ of total fatty acids. Monounsaturated fatty acids $(MUFA,\;31.4\pm9.67\%)$ and saturated fatty acids $(SFA, 30.5\pm3.81\%)$ showed a similar level. There was a positive correlation between the total lipid content and MUFA (r=0.7788, p<0.001) and a negative correlation between the total lipid content and PUFA (r= -0.7786, p<0.001) while there was no correlation between the total lipid content and SFA. The proportion of n-3 PUFA and n-6 PUFA was $29.7\pm8.73\%$ and $6,48\pm3.70\%$, respectively, in all fish samples. The n-3 PUFA was rich in sea water fish while n-6 PUFA was rich in fresh water fish. The migratory fish contained the highest level of the n-3 PUFA $(1.82\pm1.01g/100g\;muscle)$, followed by the fresh water fish $(1.09\pm1.04g/100g\;muscle)$, the reef fish $(0.90\pm0.60g/100g\;muscle)$ and the demersal fish $(0.77\pm0.38g/100g\;muscle)$. There was a positive correlation between the total lipid and n-3 PUFA content, $y=0.2083\times+0.05 (r=0.9352,\;p<0.0010)$.

• Geomechanics and Engineering
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• v.33 no.2
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• pp.141-154
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• 2023

This study investigated the effect of water retention characteristics between aged and fresh Municipal Solid Waste (MSW) on the stability of the landfill. A series of transient numerical modeling for the slope of an MSW landfill was performed considering the variation of water retention characteristics due to leachate circulation. Four different scenarios were considered in this analysis depending on how to obtain hydraulic conductivity and the aging degree of materials. Unsaturated hydraulic properties of the MSW used for the modeling were evaluated through modified hanging column tests. Different water retention properties and various landfill conditions, such as subgrade stiffness, leachate injection frequency, and gas and leachate collection system, were considered to investigate the pore water distribution and slope stability. The stability analyses related to the factor of safety showed that unsaturated properties under those varied conditions significantly impacted the slope stability, where the factor of safety decreased, ranging between 9.4 and 22%. The aged materials resulted in a higher factor of safety than fresh materials; however, after 1000 days, the factor of safety decreased by around 10.6% due to pore pressure buildup. The analysis results indicated that using fresh materials yielded higher factor of safety values. The landfill subgrade was found to have a significant impact on the factor of safety, which resulted in an average of 34% lower factor of safety in soft subgrades. The results also revealed that a failed leachate collection system (e.g., clogging) could result in landfill failure (factor of safety < 1) after around 298 days, while the leachate recirculation frequency has no critical impact on stability. In addition, the accumulation of gas pressure within the waste body resulted in factor of safety reductions as high as 24%. It is essential to consider factors related to the unsaturated hydraulic properties in designing a landfill to prevent landfill instability.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.201-206
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• 2009

It is generally accepted that organic materials are a significant factor on the soil aggregation formation but little information exists on how the formation and stabilization of aggregates in reclaimed tidelands. In this work, the effects of organic materials on the soil aggregate formation in reclaimed tidelands were determined. The soil was treated with 5 cm-size chopped fresh italian ryegrass residues (fresh organic material), commercial livestock compost with swine manure and sawdust (by product fertilizer), and fresh organic material + by product fertilizer (1 : 1 w/w) after ploughing at 20 cm soil depth. The three organic materials applied $2,000kg\;10a^{-1}$ every year. Water stable aggregate was estimated by wet-sieving method. Three years after the beginning of the experiment, water stable aggregate rate and MWD (mean weight diameter) were higher fresh organic material treatment than two other treatments. For improvement of physical property and structure of soil in reclaimed tidelands, fresh organic material treatment was more suitable than two other treatments.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.78-84
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• 1984

In order to determine the infestation patterns for metacercaria of digenetic trematodes, several kinds of fresh-water and brackish-water fish were caught in River Hyungsan, Kyungpook Province, Korea and examined from March to October in 1983. They were collected by netting, fishing with rod and line, or using the bait of crushed oil cake in transparent plastic bowls, and were dissected into the flesh, scales and 6ns with tail, and then examined for the presence and infestation density of larval trematodes. Of the 11 kinds of fish examined, the encysted larvae of Exorchis oviformis were found all of them, Metagonimus yokogawai from 9 kinds, Cyathocotyle orientalis, Metacercaria hasegawai and Metorchis orientalis from 6 kinds, alld Clonorchis sinensis from 4 Kinds in the present study. In the intensity of infestation with Clonorchis sinensis, the Korean shiner, Gnathopogon atromaculatus Nichols et Pope, was the most heavily infected species, the average number of metacercariae per grata of fish flesh being 45.5, followed by the striped shiner, Puntungia hirxi Ibersenstein 11.6, and Southern top-Inouthed minnow, Pseudorasbora larva (Temminck et Shlegel) , 9.7. The intensity of infestation with the iwetagonimus larvae in 8 species of fresh-water fish was relatively low, and the average number per gram of flesh varied from 0.23 to 9.1. In comparison, the brackish-water fish were more heavily infected and the mean number of cysts per gram of flesh in the sweetfish, Plecoglossus altiwelis, was 32.9. The results of this study generally indicate that Clonorchis sinensis and Metagcnimus yckogawai infection may occur by consuming raw fresh-water fish caught in the river Hyungpook, Kyungpook Province, Korea.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.129-139
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• 2012

This study was carried out to evaluate the chemical properties and functional characteristics, such as general composition and bioactivity compounds contents of fresh and blanched (at $95^{\circ}C$, for 5min) garlic shoot from Namhae. Also, evaluated antioxidant and antimicrobial activities of water and ethanol extract of fresh and blanched garlic shoot. The moisture content of fresh garlic steam was $ 85.14{\pm}0.35%$, crude protein and crude lipid were $0.79{\pm}0.26%$ and $2.96{\pm}0.03%$ respectively. Vitamin C content was higher in fresh garlic shoot ($7.07{\pm}0.84mg/100g$) than blanched. Total phenol and total chlorophyll contents were respectively $16.93{\pm}1.17mM/g$ and $6.70{\pm}0.46mg/g$ in fresh garlic shoot. Allicin content of blanched garlic shoot was $128.63{\pm}1.59mM/g$. This content was 1.82 times higher than the fresh garlic shoot. Total pyruvate content was higher in fresh garlic shoot ($24.63{\pm}1.59mM/g$), but thiosulfinate was higher in fresh garlic shoot. Total flavonoide was the highest in water extract of blanched garlic shoot ($3.67{\pm}0.00mM/g$). ABTS radical scavenging activity of water extract form blanched garlic shoot was $85.09{\pm}0.28%$, which was higher than the other extracts. NO radical scavenging activity of ethanol extract from blanched garlic shoot was significantly higher than the extracts from fresh garlic shoot. Antibacterial activity to S. aureus, S. enterica, B. cereus and E. coli was only indicated in water extract of fresh garlic shoot.

• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.23-29
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• 1998

• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.37-47
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• 1998

• Magazine of the Korean Society of Agricultural Engineers
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• v.8 no.2
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• pp.1141-1145
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• 1966