• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1358-1366
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• 2006

In order to study the effects of shell contents on the liquefaction resistance of the shelly sand, NGI cyclic simple shear tests were performed for the shelly sands with shell contents of 0%, 5%, 10%, 20% and 30% under the effective vertical stress of 50kPa, 100kPa and 150kPa for 40% and 55% of relative density, respectively. Cyclic simple shear test results showed that for the low effective vertical stress, liquefaction resistance increased rapidly with the increase of shell contents in both 40% and 55% relative density. On the other hand, for the high effective vertical stress, the liquefaction resistance increased slightly in 40% relative density whereas the resistance was almost same in 55% relative density. Liquefaction resistance decreased with increasing effective vertical stress for both 40% and 55% relative density. In the same effective vertical stress and shell contents, liquefaction resistance increased with the increase of relative density of sands.

• 한국식품영양과학회지
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• 제28권6호
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• pp.1226-1229
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• 1999

In order to investigate the harvest time for the production of high value added ark shell(Scapharca subcrenata) cultured at the south coast of Korea, the seasonal variations of proximate composition(mois ture, protein, fat, ash and glycogen) in the edible portions of ark shell were measured from December 1994 to December 1995. Moisture contents were the lowest in spring, but the highest in summer season being the spawning season of the S. subcrenata. The other hand, protein contents were a maximum in spring and minimum in summer. In June, just before the spawning season, fat and glycogen content was the highest, and ash content was little changed through a year. After spawning season, glycogen contents, showed decrement. In evaluating the seasonal variation of protein, moisture, and glycogen content in ark shell, the relationships of moisture protein content, moisture glycogen content and glycogen protein content show to be reverse.

• 한국환경과학회지
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• 제23권1호
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• pp.153-156
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• 2014

This study was conducted to evaluate the effects of sea urchin shell powder on nitrogen characteristics in poultry litter by assigning ninety 1-d-old male broiler chicks (Arbor Acres) to one of 3 treatments (control, 1% sea urchin shell powder, and 1% feed additives) in 3 replicates of 10 birds each. For all treatments, the overall dry matter contents were decreased (P < 0.05) as time increased, except for at 1 week. When compared with controls, the dietary sea urchin shell powder and feed additives for 0 and 3 weeks did influence their TN contents, but not for 1, 2 and 4 weeks. The treatments with sea urchin shell powder and feed additives had a significant (P < 0.05) influence on $NH_3$-N in poultry litter compared with controls. However, at 4 weeks, no marked differences were observed in $NH_3$-N contents among treatments. Treatments with 1% sea urchin shell powder might enhance the value of poultry litter as N fertilizer.

• 한국지반환경공학회 논문집
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• 제8권6호
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• pp.69-76
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• 2007

해안 연약지반 개량공사에 사용되는 모래는 대부분 다소간의 패각을 함유하게 된다. 본 연구에서는 패각 함유량이 패각질모래의 액상화 저항에 미치는 영향을 연구하기 위하여 중량비에 의해 0%, 5%, 10%, 20%, 30%의 패각을 함유한 모래의 입도를 조성하고 건조퇴적 방법으로 상대밀도가 40%와 55%인 공시체를 성형하여 50kPa, 100kPa, 150kPa의 압밀유효연직응력으로 NGI형 직접단순전단시험기를 이용해서 반복단순전단시험을 수행하였다. 연구 결과, 압밀유효연직응력이 낮을 경우에는 상대밀도가 40%, 55% 모두 패각 함유량이 많아질수록 액상화강도가 크게 증가하는 경향을 보였다. 그러나 압밀유효연직응력이 높을 경우에는 상대 밀도가 40%일 경우 약간 증가하는 경향을 얻었으나 상대밀도가 55%일 경우에는 거의 일정한 값으로 수렴하는 결과를 얻었다. 그리고 상대밀도에 관계없이 압밀유효연직응력이 증가하면 액상화 저항이 감소하는 경향을 보였다. 또한 같은 압밀유효연직응력과 패각함유량에서 상대밀도가 높아질수록 액상화강도가 증가하는 것으로 나타났다.

• 한국농공학회논문집
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• 제52권6호
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• pp.125-134
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• 2010

This study was performed to evaluate the workability, strengths and durability of polymer concrete using oyster shell that are reclaimed at public shore illegally or leaved on the surroundings of shore to prevent the environmental pollution. We investigated the effect of oyster shell powder (OSP) and $CaCO_3$. on the slump, compressive strength, flexural strength, acid sulfuric and freezing and thawing resistance as a filler of polymer concrete. Modified OSP obtained by crushing oyster shell (less than 0.15 mm size) consists of 60.47 wt% of $SiO_2$ and 39.5 wt% of $CaCO_3$. As a result of slump test by OSP and $CaCO_3$. contents, it is found that slump of specimen used OSP is lower than that used $CaCO_3$. and the more OSP contents are, its slump is increased. Compressive and flexural strength of polymer concrete using OSP are similar or slightly lower than that using $CaCO_3$. In acid sulfuric test for 5 % $H_2SO_4$ and freezing thawing test, regardless of kinds of fillers and contents are not found fatal defects in weight change, falling-off in surface and durability factor.

• 한국식품영양과학회지
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• 제29권1호
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• pp.10-14
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• 2000

In order to investigate the appropriate processing season and the production of high value-added products in ark shell(Scapharca subcrenata) cultured at the south coast of Korea, the foot muscle, mantle, and adductor muscle were analyzed for moisture, protein, fat, ash, and glycogen using specimens collected bimonthly from December 1994 to December 1995. The contents of moisture in foot muscle and mantle increased in spring season, however their proteins decreased in same season. Glycogen and fat in foot muscle, mantle, and adductor muscle were most abundant in June, just before the spawning season, but all the cmponsnts dwindled during spawning season. The other hand, the contents of ash in tissues were almost the same level through the year. Thus, the contents of moisture, protein, fat, and glycogen were almost the same level through the year. Thus, the contents of moisture, protein, aft, and glycogen were fluctuated by season. Especially, they showed a marked seasonal variation at before and after sparning season. So, a major cause of seasonal variation in S. subcrenata would be connected with a period of reproduction and spawning season.

• 대한가정학회지
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• 제25권4호
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• pp.47-55
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• 1987

This study was designed to elucidate the lipid contents, neutral lipids components and fatty acid composition in fresh shellfishes, produced in Korea. Four kinds of shellfishes including sea mussel, short-necked clam, corb shell and and ark shell were selected according to the higher sales order and cheaper retail price at fish markets in Seoul in July 1985. The results abtained were as follows; 1. The average total lipid contents in four shellfishes were 2.3% by wet weight basis. The ratios of neutrial lipid, glycolipid and phospholipid in the total lipid were 51.1 : 4.9 : 44.0 in sea mussel, 66.0 : 3.2 : 30.8 in ark shell, 37.8 : 2.2 : 60.0 in short-necked clam and 54.5 : 2.0 : 53.5 in corb shell, 2. The average value of acid value, iodine value and unsaponifiables contents of total lipids were 1.3, 217.8, 92.0 and 20.3%, respectively. 3. The composition of the neutral lipids were triglycerides, esterified fatty acids, sterylesters, free sterols and monoglycerides in four shellfishes. 4. The major fatty acid composition of total lipids were palmitic, eicosapentaenoic, docosahexaenoic and palmitoleic acids in four shellfishes. The average total unsaturated fatty acids of total lipid were 64.5%, and $\omega$-3 highly unsaturated fatty acids were 27.0%. The average p/s Ratiio were 1.3.

• 한국가구학회지
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• 제24권4호
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• pp.379-388
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• 2013

In this study, the effect of various glass fiber (GF) contents in a shell layer and shell thickness changes on the flexural property of coextruded wood plastic composites (WPCs) in combination with three core systems (weak, moderate, and strong) was investigated. GF behaved as an effective reinforcement for the whole coextruded WPCs and GF alignments in the shell layer played an important role in determining the flexural property of the coextruded WPCs. At a given shell thickness, the flexural property of the whole coextruded WPCs was improved with the increase of GF content in shell. For core quality, when the core is weak, increase of GF content in shell led to improved flexural property of the whole composites and increase of shell thickness helped it. On the other hand, when the core is strong, the flexural property of the whole composites showed reduced features at low GF content in shell and increase of shell thickness aggravated it. This approach provides a method for optimizing performance of the coextruded WPCs with various combinations of core-shell structure and properties.

• 한국식품영양학회지
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• 제25권2호
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• pp.224-232
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• 2012

This study was conducted to investigate the effect of chestnut inner shell powder on antioxidant activity and the quality characteristics of cookies. Cookies were prepared with different amounts of chestnut inner shell powder(in ratios of 0, 0.5, 1, 3 and 5% to the flour quantity). The antioxidant activity was estimated by DPPH free radical scavenging activity and the total phenol content in chestnut inner shell powder and cookies. For analyzing quality characteristics, bulk density and pH of the dough, spread factor, loss rate, leavening rate, color, texture profile analysis, and sensory evaluations were measured. The spread ratio, a values, total phenol contents and DPPH free radical scavenging activity of cookies significantly increased with increasing chestnut inner shell powder(p<0.001), while the pH of the dough, L values and b values of the cookies significantly decreased with increasing chestnut inner shell powder content(p<0.001). The consumer acceptability score for the 3% chestnut inner shell cookie groups ranked significantly higher(p<0.01) than those of the other groups in overall preference, flavor, taste and color. From these results, we suggest that chestnut inner shell is a good ingredient for increasing the consumer acceptability and the functionality of cookies.

• 한국토양비료학회지
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• 제38권5호
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• pp.281-286
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• 2005

굴패각으로부터 제조된 굴패화석 비료 시용이 토양의 미시환경에 미치는 영향을 조사하기 위해 토양 내 microbial biomass 함량과 주요 토양효소의 활성을 조사하여 다음과 같은 결과를 얻었다. 굴패화석 시용량이 증가함에 따라 토양 내 microbial biomass C, N, P 함량이 크게 증가하였으며, 양분의 가급화와 관련 있는 주요 토양효소의 활성이 크게 증진되었다. 본 연구조건에서 굴패화석 시용에 따른 산성토양의 pH 개선은 microbial biomass P 함량 증진과 urease, ${\beta}$-glucosidase, alkaline phosphomonesterase의 활성증진에 직접적으로 영향을 주었으며, microbial biomass P와 phosphomonoesterase 활성증진은 유효인산 함량증진에 직접적으로 영향을 준 것으로 조사되었다. 결론적으로 약산성의 공시토양에 알카리성 제재인 굴패화석 시용은 토양생물과 효소 활성을 증대함으로써 작물생육에 필요한 양분공급 및 가용율 향상시키는 효과가 있는 것으로 평가되었다.