• 건축구조
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• v.9 no.4
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• pp.54-57
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• 2002

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.33-34
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• 2022

The purpose of this study was to provide basic data for applying oyster shells and egg shells as fireproof cladding materials by substituting fine aggregates for oyster shell powder and egg shell powder, and comparing strength and fire resistance performance. The reason for the high strength was thought to be that the oyster shell had higher strength than the egg shell itself, and both ESP and OSP were measured at a backside temperature of less than 500℃, so it was judged that it could be used as a fireproof coating for steel structures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.46-47
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• 2020

Oyster shells and egg shells consist of CaCO3, which is known to have excellent fire performance as the main component, and research is currently being conducted as a fireproof board material. Therefore, in this study, the physical and chemical properties of oyster shell powder and egg shell powder are studied to find out the applicability of fireproof board

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.21-26
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• 2007

This study was carried out to investigate the effects of tree-spray of calcium formate compound extracted from oyster shell with several active agents on the calcium concentration, fruit skin shape and quality of 'Fuji' apple. The tree-spray of calcium formate compound extracted from oyster shell (Os-CaF, $52.4\;mg{\cdot}kg^{-1}$) appeared to have more effectiveness on the calcium translocation into leaves, fruit skin and flesh than control. Addition of adjuvants to Os-CaF increased calcium concentration of 'Fuji' apple when sprayed three times before harvest. Among the active agents examined, the treatment ascorbic acid and poly-vinyl alcohol (PVA) in leaves, Ag-colloidal and PVA in fruit skin, ascorbic acid, Ag-colloidal, and PVA in fruit flesh exhibited highest effectiveness. Fruit qualities (fruit weight, firmness, soluble solids, acidity and Hunter value) were not affect by Os-CaF on different concentrations and solutions of active agents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.1_2
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• pp.65-75
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• 1973

Morphological variations of the Korean Oyster, Crassostrea gigas, were studied on the basis of the oyster samples collected from seven ecologically different areas in May and October of 1972 respectively. The sampling areas were Daecheon and Buan in the west coast, Namseong, Cha-myeon, Imyeong and Chubong in the south coast and Pohang in the east coast. The average sizes of the oysters of the west coast were smaller than those of the south coast as well as those of the east coast. The oysters of the east were largest in size, The oysters from subtidal habitats (Chubong and Pohang) had elongated shells and those from intertidal habitats (Buan, Namseong, Imyeong and Chamyeon) had slanted shells. The samples from subtidal habitats showed size variations depending on cultural methods applied. The oysters from Chubong reared by hanging method had their shells as compared to those from Pohang reared by bottom culture method. The ratio of shell height to shell length showed a great variation froms areas to areas with a significant differences. The fatness (meat weight / shell weight) of all the samples collected in October revealed higher value than those collected in May. The oysters from Chubong showed maximum fatness, and those of Pohang showed minimum fatness. Seasonal variations in fatness was not significant in Chubong. On the other hand, it was relatively significant in the oysters from Pohang, Chamyeon, Imyeong and Buan. Water content of the oyster meat was greater in October than in May. It also showed variations in the sampling areas with higher values in the oyster from Imyeong and Chamyeon than those from Chubong, Pohang and Daecheon.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.94-95
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• 2020

Oyster shells are characterized by coarse and coarse grains, but similar in strength to sand, and egg shells are fine grains but weak in strength. In terms of supply and demand of raw materials, oyster shells can be supplied only in limited periods and regions in winter and south coast of the year, but egg shells have the advantage of being able to supply and supply nationwide 365 days. This study aims to study the change in strength characteristics by mixing oyster shell powder and egg shell powder with the same particle size and mixing up to 150%. The conclusions of the flexural and compressive strength tests of mortar mixed with oyster shell powder and egg shell powder are as follows. The 7-day flexural and compressive strength with ESP added and the 3-day flexural and compressive strength with OSP added were similar, which is thought to be because the strength of OSP is higher than that of ESP.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.72-82
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• 1986

There were three important species among the marine organisms which were cultured in the inter tidal zone in the old days, and an ark-shell was one of them. Exaiming old books and reports concerning fishery were made in order to reveal the history and industrial trend of ark-shell culture. Ark-shell was called by the different names in the old days "Komak" and "Sohap". The name of Komak was originated in the southern coast area in the 1,700s, and from the begining of 18 century Komak was used only. Ark-shell was produced in all southern and western coast areas, where a little of fresh water flows into the calm inner sea and the intertidal zone is well developed. It was well known that ark-shells shell as well as its flesh took the effect of a medicine. Its culturing method in Korea seems to be derived from China in the beginning of 19 century, it was cultured first at the southern area of Chollanam-do. It was considered as the side business, but after Korean war it is produced on the basis of cooperative work, now its production is quite increased (more than $5,000\fra{M}{T}$) due to the goverments development policy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.321-326
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• 1984

Three kinds of mangrove oysters, species of high commercial value in tropical regions, were collected in Cocineta Bay, Venezuella in 1976, at the mouth of Hoffman River, Liberia in 1978 and at the West Coast of Benzina, Indonesia in 1984. Crassostrea rhizophorae from Venezuella showed the most round shell form and greatest shell capacity. In addition, the fatness condition of $9.63\%$ topped the ether two species. Crassostrea tulipa inhabiting Liberia had the most elongated shell form. Although shell capacity of this species was almost similar to Crassostrea rhizophorae, it took up intermediate position in fatness condition with $8.15\%$. Crassostrea beleheri from Indonesia. just as rounded as C, rhizophorae, showed the biggest values in total weight and shell weight but the least fatness with $6.62\%$.