• 한국어병학회지
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• 제19권1호
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• pp.35-43
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• 2006

V. vulnificus 오염으로부터 패류의 안전성을 조사하기 위해 굴을 V. vulnificus에 인위감염시키고 4℃와 25℃에서 패각 유무에 따른 V. vulnificus 균수 변화를 조사하였다. V. vulnificus가 있는 인공해수에 침지시킨 굴에서 분리된 V. vulnificus 균수는 인공해수 속의 균수보다 많았다. 굴을 4℃에 보관하는 경우는 실험기간 동안 V. vulnificus 균수의 차이가 관찰되지 않았지만 25℃에 보관하는 경우는 빠른 균수의 증가가 관찰되어 보관온도가 균수 변화에 많은 영향을 주었다. 여러 염분농도, 5, 15 및 35 ‰의 인공해수에서 V. vulnificus 균수는 25℃와 4℃에서 모두 감소하였다. 그러나 4℃에서 균수의 감소율은 25℃에서 보다 빨랐고 4℃에서 염분도 V. vulnificus 균수 감소율에 영향을 주어 35 ‰의 인공해수에서 가장 높은 감소율을 보였다.

• 한국수산과학회지
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• 제49권4호
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• pp.460-466
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• 2016

From 2013 through 2015, we investigated the contamination status and antimicrobial resistance patterns of pathogenic Vibrio parahaemolyticus in commercially valuable seawater and shellfish (Oyster Crassostrea gigas, short-neck clam Venerupis philippinarum, ark shell Scapharca broughtonii and mussel Mytilus galloprovinciallis) from the southern coast of Korea. The detection rate of V. parahaemolyticus was highest in short-neck clams (23.7%), followed by ark shells (19.2%), oysters (15.9%), mussels (13.6%), and seawater (8.6%). The following percentages of PCR assays of shellfish were positive for the thermostable direct hemolysin-related hemolysin gene (trh) : oysters (12.8%), short-neck clams(11.8%), and ark shells (3.4%). Similar assays for the thermostable direct hemolysin gene (tdh) resulted in positive results for short-neck clams (5.9%) and ark shells (3.4%). Antimicrobial resistance was present in 100% of 8 tdh (+) and 2 trh (+) V. parahaemolyticus isolates challenged with ampicillin. However, all pathogenic V. parahaemolyticus were sensitive to 14 other antibiotics. To ensure the safety of shellfish consumption, the continuous monitoring of the prevalence and distribution of virulence factors of V. parahaemolyticus in shellfish farms is needed.

• 한국유기농업학회지
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• 제20권4호
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• pp.475-490
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• 2012

Since 1997, Korean Ministry of Knowledge Economy and Ministry of Environment have established data on some 400 basic raw and subsidiary materials and process like energy, petro-chemical, steel, cement, glass, paper, construction materials, transportation, recycling and disposal etc by initiating establishment of LCI database. Regarding agriculture, Rural Development Administration has conducted establishment of LCI database for major farm products like rice, barley, beans, cabbage and radish etc from 2009, and released that they would establish LCI database for 50 items until 2020 later on. The domestic LCI database for seeds, seedling, agrochemical, inorganic, fertilizer and organic fertilizer etc is only at initial stage of establishment, so overseas LCI databases are brought and being used. However, since the domestic and overseas natural environments differ, they fall behind in reliability. Therefore, this study has the purpose to select organic farming materials, survey the production process for various types of organic farming materials and establish LCI database for the effects of greenhouse gas emitted by each crop during the process. As for selecting methods, in this study organic farming materials were selected in the method of direct observation of material and bottom-up method a survey method with focus on the organic farming materials admitted into rice production. For the basic unit of carbon emission amount by the production of 1kg of organic farming material, the software PASS 4.1.1 developed by Korea Accreditation Board under Ministry of Knowledge Economy was used. The study had the goal to ultimately provide basic unit to calculate carbon emission amount in executing many institutions like goal management system and carbon performance display system etc in agricultural sector to be conducted later on. As a result, emission basic units per 1kg of production were calculated to be 0.04968kg-$CO_2$ for oystershells, 0.004692kg-$CO_2$ for expanded rice hull, and 1.029kg-$CO_2$ for bordeaux mixture liquid.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1463-1474
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• 2008

In order to investigate stabilization effect and sustainability on As-contaminated farmland soils which were affected the abandoned mine site and stabilized by zerovalent iron(ZVI) and industrial by-products, batch-scale and pilot-scale tests were carried out. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used in treatment materials to reduce the As leaching. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. The results of batch-scale tests was shown that the reduction of As concentration was observed in all samples and it was expected that ZVI and steel refining slag were more effective than other treatment materials to stabilize As compounds. In pilot-scale tests, columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag in the same mixing ratio of 3%. Distilled water was discharged into the columns with the velocity of 0.3 pore volume/day. During the test, pH, EC, Eh and As concentration were measured in the regular term(1pore volume). after six months, pilot-scale tests were retested to investigate sustainability of treatment materials. As a result, It was shown that the leachate from control column was continuously released during the test period and its concentration was greater than $100ug{\cdot}L^{-1}$ which was exceeded the national regulation of water discharged to river or stream ($50ug{\cdot}L^{-1}$). On the other hand, soil treated with ZVI and steel refining slag showed that the concentrations of leachate were lower than national regulation of water discharged to river or stream. Therefore it was expected that ZVI and steel refining slag could be applied to the farmland site as the alternative treatment materials.

• 한국환경과학회지
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• 제16권6호
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• pp.707-714
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• 2007

A laboratory experiment was performed to investigate nitrogen removal by the soil column. The addition of 20% waste oyster shell to the soil accelerated nitrification in soil column. The $NO_3^--N$ concentration in the effluent decreased with the decrease of HRT(Hydraulic Retention Time). When methanol and glucose added as carbon sources, the average removal rates of T-N(Total Nitrogen) were 82% and 77.9%, respectively. The $NO_3^--N$ removal by methanol supplementation in soil column can likely be attributed to denitrification. In continuous removal of nitrogen using the soil column, the COD(Chemical Oxygen Demand) and $NH_4^+-N$ removed simultaneously in organic matter decomposing column. The greater part of $NH_4^+-N$ was nitrified by the percolated through nitrification column, and the little $NH_4^+-N$ was found in the effluent. The T-N of 87.4% removed at HRT of 36 hrs in denitrfication column. Because of nitrified effluents from nitrification column are low in carbonaceous matter, an external source of carbon is required.

• 한국세라믹학회지
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• 제47권5호
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• pp.401-406
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• 2010

For the lower-temperature preparation of calcium monoaluminate(CA, C:CaO, A:$Al_2O_3$) clinker which is hard to synthesize purely within its melting point, an equimolar hydrate was obtained and then used as a starting raw material of clinker burning. The hydrate was prepared from a mixture of waste oyster shell and industrial aluminium hydroxide by heating to $1200^{\circ}C$, grinding and mixing with water. The hydrate was composed of amorphous aluminium hydroxide and $C_3AH_6$(H:$H_2O$) formed by resolution-precipitation mechanism of the system C-A-H. By heating the hydrate, nearly pure and porous calcium monoaluminate clinker was formed at $1400^{\circ}C$ which is fairly lower temperature than that of its melting point. The formation of calcium monoaluminate was performed mainly by the reaction between amorphous alumina and $C_{12}A_7$ caused by the decomposition of $C_3AH_6$. The immediate and earlier formation of $C_{12}A_7$ seemed to be accelerated by not only high surface area and instability of the thermally decomposed hydrate but also the catalytic effect of water decomposed from the hydrate. The final calcium monoaluminate clinker was very porous because of the influence of highly porous shape of the thermally decomposed hydrate.

• 한국축산식품학회지
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• 제43권2호
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• pp.232-244
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• 2023

We investigated the effects of different phosphate replacements on the quality of ground pork products cured with sodium nitrite or radish powder to determine their potential for achieving clean-label pork products. The experimental design was a 2×5 factorial design. For this purpose, the ground meat mixture was assigned into two groups, depending on nitrite source. Each group was mixed with 0.01% sodium nitrite or 0.4% radish powder together with 0.04% starter culture, and then processed depending on phosphate replacement [with or without 0.5% sodium tripolyphosphate; STPP (+), STPP (-), 0.5% oyster shell calcium (OSC), 0.5% citrus fiber (CF), or 0.5% dried plum powder (DPP)]. All samples were cooked, cooled, and stored until analysis within two days. The nitrite source had no effect on all dependent variables of ground pork products. However, in phosphate replacement treatments, the STPP (+) and OSC treatments had a higher cooking yield than the STPP (-), CF, or DPP treatments. OSC treatment was more effective for lowering total fluid separation compared to STPP (-), CF, or DPP treatments, but had a higher percentage than STPP (+). The STPP (+) treatment did not differ from the OSC or CF treatments for CIE L^* and CIE a^*. Moreover, no differences were observed in nitrosyl hemochrome content, lipid oxidation, hardness, gumminess, and chewiness between the OSC and STPP (+) treatments. In conclusion, among the phosphate replacements, OSC addition was the most suitable to provide clean-label pork products cured with radish powder as a synthetic nitrite replacer.

• 대한토목학회논문집
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• 제44권1호
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• pp.33-39
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• 2024

본 연구에서는 대표적인 해양 폐기물인 패각을 자원화하여 건설재료에 활용하고, 재료의 특성에 미치는 영향을 평가하였다. 꼬막, 굴 등 국내에서 많이 발생하는 패각을 세척 및 전처리하여 잔골재 대체재로서 활용하였으며, 패각의 대체율 및 세척 여부 등의 조건에 따라 시멘트 모르타르 시편을 제작하였다. 서로 다른 조건하에 타설된 모르타르 시편의 압축강도를 평가하고, XRD, SEM, micro-CT 등의 미세구조 분석 방법들을 활용하여 각 시편의 고체 및 공극 구조를 분석하였다. 결과를 통해, 굴과 꼬막 패각이 서로 다른 탄산칼슘의 동질이상으로 구성되어 있는 것을 확인하였으며, 각각의 미세구조 특성에 의해 잔골재 대체재로 활용 시, 모르타르의 역학적 물성 차이에 영향을 미치는 것을 확인하였다.

• 보존과학회지
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• 제20권
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• pp.9-22
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• 2007

문화재의 생물방제를 목적으로 개발되어 시판되고 있는 3종의 식물 추출 천연 살충 살균제에 대한 문화재의 재질에 미치는 영향을 평가하였다. 평가 대상 재질은 1) 견직물 : 염색하지 않은 견직물, 황벽, 오배자, 오배자(명반 후매염), 오배자(녹반 후매염), 치자, 울금, 도토리, 도토리(녹반 후매염), 자초, 천근, 천근(명반 후매염), 홍화(홍염색), 소목, 소목(명반 선매염, 후매염) 염색 및 쪽, 쪽과 황벽 복염, 쪽과 소목 복염 견직물 2) 면직물 : 염색하지 않은 면직물, 황벽, 오배자, 오배자(명반 후매염), 치자, 도토리, 도토리(녹반 후매염), 자초, 천근, 천근(명반 후매염), 홍화(홍염색), 소목, 소목(명반선매염, 후매염) 염색 및 쪽, 쪽과 소목 복염 면직물, 3) 염색하지 않은 저마직물 4) 한지 : 염색하지 않은 한지, 소목, 쪽, 치자, 홍화(홍염색), 황벽 염색 한지 5) 안료분말 :석청 석록, 연단, 석간주, 주사, 주, 패각호분, 밀타승,대자, 석황, 쪽, 백토, 연백 남전 5)채색편 : 석청, 석록, 연단, 석간주, 주사, 주, 패각호분, 밀타승, 대자, 석황, 쪽, 백토, 연백, 남전이다. 시험은 시료를 습도 $55{\pm}1%$. 온도 $20{\pm}2^{\circ}C$의 환경에서 약제의 권장 농도의 10배에 9개월간 노출 시킨 후 기준 시료와의 색차와 인장강도를 비교 평가하였다. 약제 노출 후 염색을 하지 않은 견직물 면직물 저마직물 한지는 약제에 의한 색상 변화는 거의 일어나지 않았으나, 염색 견직물 면직물 한지는 도토리나 천근 염색 직물 등이나 치자 염색 한지를 제외하고는 대부분 일반인도 인식이 가능한 뚜렷한 색상차가 발생하였다. 특히 울금 염색 견직물은 가장 색상차가 뚜렷하였다. 그리고 안료분말이나 채색편은 납, 구리, 비소, 수은 함유 안료 및 식물성 안료 등에서 뚜렷한 색상차가 발생하였다. 인장강도는 염색하지 않은 견직물은 약제에 거의 변화가 없으며 면직물은 약간 감소하는 경향을 보이나, 염색을 한 견직물이나 면직물은 강도의 증가나 감소가 뚜렷하였다. 특히 천근 염색 견직물은 10% 이상의 강도 감소가, 쪽 염색 견직물은 10% 이상의 강도 증가가 일어났으며, 천근과 소목(명반 후매염) 염색 면직물은 10% 이상의 강도 감소 현상이 일어났다.

• 대한환경공학회지
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• 제30권11호
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• pp.1116-1122
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• 2008

기존의 하수슬러지 소각재를 용융하여 경량 골재로 재활용하는 기술은 물성이 일정하지 않으며, 또한 하수슬러지만 소각 용융한 경우에는 물성이 경량골재 기준을 만족하지 못해 사용이 제한적인 실정이다. 따라서 본 연구에서는 30%의 함수율을 가진 건조 하수슬러지를 대상으로 굴 패각, 폐 주물사, 쇠의 녹과 같은 무기성 폐기물 첨가제를 이용해 CaO/SiO$_2$, SiO$_2$/Al$_2$O$_3$, Fe$_2$O$_3$/SiO$_2$비를 조절하여 낮은 용융온도에서도 균일한 품질의 골재용 슬래그를 생산하고자 하였다. 1,400$^{\circ}C$에서 20분간 용융하였을 때, 굴패각 첨가실험에서는 CaO/SiO$_2$ 비 1.00, 폐 주물사 첨가 실험에서는 SiO$_2$/Al$_2$O$_3$ 비 3.0 그리고 쇠의 녹 첨가 실험에서는 Fe$_2$O$_3$/SiO$_2$비 0.6에서 밀도가 각각 2.24 g/cm$^3$, 2.45 g/cm$^3$, 2.73 g/cm$^3$였으며, 24시간 수 흡수성은 각각 4.72%, 1.44%, 0.37%로 가장 우수한 슬래그 생산이 가능한 것으로 판단되었다. 폐기물 첨가제를 첨가한 용융슬래그를 생산함으로써 자원순환 및 환경오염 방지 효과가 기대된다.