• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.3
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• pp.187-197
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• 2010

Carbon dioxide Capture and Storage(CCS) is regarded as one of the most promising options to response climate change. CCS is a three-stage process consisting of the capture of carbon dioxide($CO_2$), the transport of $CO_2$ to a storage location, and the long term isolation of $CO_2$ from the atmosphere for the purpose of carbon emission mitigation. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the $CO_2$ mixture captured from the power plants and steel making plants contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_2$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification, transport and injection processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to analyze the impact of these impurities on the whole CCS process at initial design stage. The purpose of the present paper is to compare and analyse the relevant physical property models including BWRS, PR, PRBM, RKS and SRK equations of state, and NRTL-RK model which are crucial numerical process simulation tools. To evaluate the predictive accuracy of the equation of the state for $CO_2-SO_2$ mixture, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $SO_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable physical property model with optimized binary parameter in designing the $CO_2-SO_2$ mixture marine geological storage process.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.3
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• pp.217-226
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• 2009

Marine geological storage of $CO_2$ is regarded as one of the most promising options to response climate change. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources, to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the captured $CO_2$ mixture contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_x$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification and transport processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of the present paper is to compare and analyse the relevant equations of state including PR, PRBM, RKS and SRK equation of state for $CO_2-N_2$ mixture. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $N_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable equation of state and relevant binary parameter in designing the $CO_2-N_2$ mixture marine geological storage process.

• Journal of the Korean Institute of Gas
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• v.22 no.5
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• pp.53-61
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• 2018

Low-salinity water based polymerflooding (LSPF) is one of promising enhanced oil recovery (EOR) method that has the synergetic effect of combining polymer injection method and low-salinity water injection method. In order to maximize EOR efficiency, it is essential to design low-salinity water appropriately considering the properties of polymer. In this aspect, the main purpose of this study is to investigate the effect of pH and $SO_4{^{2-}}$ ion which one of PDI (Potential Determining Ion) on oil production when applying LSPF to carbonate oil reservoir. First, the stability and adsorption of polymer molecule were analyzed in different pH of injection water and $SO_4{^{2-}}$ concentration in injection water. As a result, regardless of pH and $SO_4{^{2-}}$ concentration, when $SO_4{^{2-}}$ ion was contained in injection water, the stability of polymer solution was obtained. However, from the result of polymer retention analysis, in neutral state of injection water, since $SO_4{^{2-}}$ interfered the adsorption of polymer, the adsorption thickness of polymer was thinner as $SO_4{^{2-}}$ concentration was higher. On the other hand, when injection water was acidic as pH 4, the amount of polymer adsorption increased with the injection of polymer solution, so the mobility of polymer solution was greatly lowered. From the results of wettability alteration due to low-salinity water effect, in the case of neutral injection water injected, as $SO_4{^{2-}}$ concentration was increased, more oil which attached on rock surface was detached, altering wettability from oil-wet to water-wet. On the other hand, in acidic condition, due to complex effect of rock dissolution and polymer adsorption, wettability of the entire core system was less altered relatively to neutral condition. Therefore, it was evaluated that better EOR efficiency was obtained when injecting low-salinity water based polymer solution containing high concentration of $SO_4{^{2-}}$ with neutral condition, enhancing the oil production up to 12.3% compared to low-salinity water injection method.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.252-260
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• 1996

In this article, we investigate into the structural changes of liposome to design its functional membranes by the synthesis of two types of liposomes, DPPC liposome and DTAB of hydrocarbon substance/DPPC liposome. The changes of membrane structures are evaluated by the CF fluorescent intensity measured above and below the phase transition temperature of the membrane, $t_c=41^{\circ}C$. CF fluorescent intensities are enhanced by the CF leakage from DPPC liposome at $45^{\circ}C$, while no changes are observed at $20^{\circ}C$. Under the same conditions, it is observed that the intensity enhanced by CF leakage from DPPC/DTAB liposome is larger than that of DPPC liposome alone, which suggests that DPPC/DTAB liposome has irregular arrangement. Under the presence of $Ca^{2+}$, Quin 2 fluorescent intensity in either DPPC liposome or DPPC/DTAB liposome is significantly increasing at $45^{\circ}C$, while almost none of the changes are observed at $20^{\circ}C$. The fluorescent intensity of DPPC liposome turns out to be larger than that of DPPC/DTAB liposome, which suggests that the DPPC/DTAB liposome is structurally more stable than the DPPC liposome. Additionally, when the analysis is done to observe changes in the shapes of membrane surfaces with ANS fluorescent, ANS fluorescent under DPPC or DPPC/DTAB liposome shows each of different appearances at $45^{\circ}C$ and $20^{\circ}C$ respectively. This result indicates that its respective membrane fluidity is changing above and below of the designated temperatures in phase transition. As to the magnitude of change of its membrane fluidity, DPPC liposome is much larger than DPPC/DTAB liposome. As far as the temperature in phase transition measured by DSC are concerned, it is $41^{\circ}C$ and $32^{\circ}C$ for DPPC and DPPC/DTAB liposome respectively, which suggests that DPPC/DTAB liposome has an irregular molecular arrangement in its structure. That is, it is summed up that DPPC/DTAB turns out to be structurally stable, even so, its structure is irregularly arranged.

• Journal of Dairy Science and Biotechnology
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• v.29 no.1
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• pp.23-31
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• 2011

Domestic dairy industry is now standing at the crossroad for planning next fifty years, mainly because economic and environmental situations surrounding Korean peninsula are fast changing. For the aspects of dairy consumption, fresh milk consumed less, while consumption of the other milk and dairy products is slightly increasing every year. In 2010, it is approximately estimated that 1,939,000 tons of raw milk was used and the supply would be short by about 35,000 tons, based on the amounts in the previous year. Currently, multilateral negotiations against US and EU are underway. When it will be in effect in the future, significant damage would be expected in the dairy and livestock sectors, leading to cut domestic milk supply. Quality of farm-gate milk is graded as 1A on average 90% or more, loaded with very low in microbial and somatic cell counts. Therefore, policy implications have to be placed toward switch currently the UHT processing method to Pasteurization or the LTLT technology, by which natural flavors and nutrients in milk mostly remain after heat treatment. Domestic cheese products comprise only 10% and the rest is occupied by the various kinds of imported natural products. The market size keeps increasing up to 65,423,000 tons last year. When it comes to vitalization of our natural cheese industry, cheese whey, which is a main by-product in cheese manufacture, is a critical issue to be solved and also "On-Farm Processing" would be combined with a growth of big dairy companies when few immediate issues among the relevant regulations will be eased and alleviated in the near future. Fermented milk market is recorded as a single area of gradual increase in the past 10 years, Korea. Fermented yogurts with health claims targeted stomach, liver, and intestine are popular and has grown fast in sales amounts. In this context, researches on beneficial probiotic lactic acid bacteria are one of the important projects for domestic milk and dairy industries. Labelling regulations on efficacy or health-promoting effects of functional dairy products, which is the most important issue facing domestic dairy processors, should be urgently examined toward commercial expression of the functionality by lawful means. Colostrum, a nutrition-rich yellowish fluid, is roaded with immune, growth and tissue repair factors. Bovine colostrum, a raw material for immune milk preparations and infant formula, can be used to treat or prevent infections of the gastrointestinal tract. Nanotechnology can be applied to develop new milk and dairy products such as micro-encapsulated lactase milk for consumers suffering lactose intolerance. Raw milk is suggested to be managed by its usage in the processing line because imbalance of supply and demand is structural problem in every country and thus the usage systems as in the advanced dairy countries is worth of bench-marking to stabilize milk supply and demand. Raw milk produced is desirable to divide into the three parts; domestic, import, and buffering purposes. It is strongly recommended that a domestic dairy control center as an institutional framework should be urgently established as is Dairy Board in New Zealand and Australia. Lastly, government policy should be directed to foster the highly-educated people who are majoring in Dairy Sciences or working in the dairy industry by means of financial support in studying and training abroad as well.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.276-282
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• 2008

It is estimated that over 80% of deer antlers produced in the world are consumed in Korea. However, mislabeling or fraudulent replacement of costly antlers with cheaper ones is one of the most common problems in the domestic antler market. Therefore, there is a great need for the development of technology to identify species of antlers. This study was carried out to develop an accurate and reliable method for the identification and authentication of species or subspecies of antlers using DNA sequence analysis and comparison of mitochondrial cytochrome band D-loop region genes among antlers of five deer species, Cervus elaphus sibericus, Cervus elaphus canadensis, Cervus nippon, Cervus elaphus bactrianus and Rangifer tarandus. A variable region of cytochrome band D-loop genes was amplified using PCR with specifically designed primers and sequenced directly. The cytochrome band D-loop region genes showed different DNA sequences between the species of antlers and thus it is possible to differentiate between species on the basis of sequence variation. To distinguish between reindeer (Rangifer tarandus) antlers and other deer antlers, PCR amplicons of the cytochrome b gene were digested with the restriction enzymes NlaIV and TaqI, respectively, which generates a species-specific DNA profile of the reindeer. In addition, samples of 32 sliced antlers labeled Cervus elaphus sibericus from commercial markets were collected randomly and the mt DNA D-loop region of these antler samples was sequenced. Among the antler samples investigated, only 62.5% were from Cervus elaphus sibericus, and others were from Cervus elaphus bactrianus (25.0%), elk (Cervus elaphus canadensis) and reindeer (Rangifer tarandus). Our results suggest that DNA sequencing of mt DNA and PCR-RFLP methods using NlaIV and TaqI enzymes are useful for the identification and discrimination of deer antler species by routine analysis.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.63-74
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• 2006

During the construction of circular underground pipe, the non-proper compaction along the pipe and the decrease of compaction efficiency have been the main problems to induce the failure of underground pipe or facility. The use of CLSM (controlled low strength materials) should be one of the possible applications to overcome those problems. In this research, the full-scaled field test and the numeric analysis using PENTAGON-3D FEM program were carried out for three different cases on the change of backfill materials, including the common sand, the soil from construction site, and the CLSM. From the full-scaled test in field, the use of in-situ CLSM as backfill materials reduced the vertical and lateral deformation of the pipe, as well as the deformation of the ground surface. The main reason for reducing the deformation would be the characteristics of the CLSM, especially self-leveling and self-hardening properties. The measured earth pressure at the surround of the corrugated pipe using the CLSM backfills was the smaller than the other cases, and the absolute value was almost zero. Judging from the full-scaled field test and FEM analysis, the use of CLSM as backfill materials should be one of the best choices reducing the failure of the underground pipes.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.124-129
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• 2013

The method for detection foods containing allergenic materials by PCR was developed in this study. To detect allergenic raw material from processed food, species specific primer which up to 200bp for PCR product were designed or selected from advanced research. As target materials, 14 items were selected (12 target materials for allergen in Korea, 2 target materials for allergen in foreign countries). The amplicon size for eggs, milk, buckwheat, peanuts, beans, wheat, mackerel, crab, shrimp, pork, peach, tomato, almond, and sesame were confirmed 281, 131, 138, 120, 118, 127, 211, 174, 231, 138, 174, 132, 103, and 220bp, respectively. And any non-specific bands were not detected among each others. Detection method for allergenic material developed in this study could be used to investigate inaccurate goods for allergen labeling or non-intentional contaminant during processed foods manufacturing. In addition, the system will be usefully to detection accurate allergenic raw materials of export for other countries.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.68-73
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• 2012

In this study, a method was developed using molecular biological technique to distinguish an authenticity of meats for processed meat products. The genes for distinction of species about meats targeted at 12S or 16S genes in mitochondrial DNA and the species-specific primers were designed by that PCR products' size was around 200bp for applying to processed products. The target materials were 10 species of livestock products and it checked whether expected PCR products were created or not by electrophoresis after PCR using species-specific primers. The results of PCR for beef, pork, goat meat, mutton, venison, and horse meat were 131, 138, 168, 144, 191, and 142 bp each. The expected PCR products were confirmed at 281, 186, 174, and 238 bp for chicken, duck, turkeymeat, and ostrich. Also, non-specific PCR products were not detected in similar species by species-specific primers. The method using primers developed in this study confirm to be applicable for composite seasoning including beefs and processed meat products including pork and chicken. Therefore, this method may apply to distinguish an authenticity of meats for various processed products.

• Food Industry
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• s.181
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• pp.10-37
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• 2004

식용유지는 식용으로 이용할 수 있는 가시적인 상태의 액상(oil) 또는 고체상(fat)의 식용기름을 말하지만 식품산업 측면에서는 가시적인 상태의 유지(가시지방)뿐만 아니라 유지가공 식품이나 기타의 식품에 함유되어 섭취되는 비가시적인 상태의 유지(비가지 지방)도 포함될 수 있다. 식용유지는 생명을 유지하는데 없어서는 안될 영양소로서 탄수화물 단백질과 함께 3대 영양소 중의 하나이며 1g당 9kcal를 내는 고도로 농축된 에너지원이면서 필수지방산의 공급원이고 비타민 A, D, E 등의 지용성 비타민과 기타 특수한 영양성분의 운반체로서 높은 영양적 가치를 갖는다. 지방성분은 음식물로부터 섭취가 불가능할 경우에는 체내에서 탄수화물이나 단백질을 기질로 하는 대사과정에서 합성되어 지질 또는 필수지방산과 지용성 비타민은 식품으로 지방질과 함께 흡수되어야 하므로 식품의 한 성분으로 지방의 중요성을 인정받고 있다. 1960년대 이후 국민소득의 증가와 함께 식생활도 다양화되고 서구화 간편화되면서 지방 함량이 높은 식품과 유지를 이용한 식품의 소비가 증가하였고 전체적인 유지 소비량도 늘어나는 추세에 있다. 60년대 초에는 총열량 중 지방이 차지하는 비율이 $6\%$ 정도였으나 최근에는 급격히 증가되어 2000년말 현재 $25.5\%$로 증가하였다. 97년까지 계속 증가하던 공급 에너지량은 98년 IMF의 영향으로 2,799 kcal까지 감소했으나 99년 들어 IMF 이전 수준으로 회복되었다. 또한 연간 일인당 순 식용유지류 공급량은 1990년대 까지 급격히 증가하였으나 이후로는 소폭 증가하는 추세이다. 2000년말 현재 식용유지 총 공급량은 76만2 천톤으로써 99년 73만5 천톤에 비해 2.7만톤이 증가하였다. 1998년 IMF 시기를 제외하고는 공급물량은 계속해서 증가 추세이다. 특히 1998년도에 비하여 2000년도에 식물성 유지는 2배 가까이 증가하였으나, 동물성 유지는 절반 이하로 감소되는 추세이며 공급물량으로 보면 대두유, 팜유가 주요 유종으로 식물유지 전체에서 차지하는 비중이 $72.3\%$로 압도적이다. 라면용 튀김기름과 마가린 쇼트닝의 원료로서 대부분 사용되는 팜유를 제외하고 가정용 식용유의 대부분을 차지하는 대두유가 이처럼 식용유지 시장의 대부분을 차지하게 된 이유는 첫째, 90년대 초반 수입 자유화 이후 타 유종 대비 낮은 가격을 형성하여 유지업체가 수입을 늘린 것이고 둘째로는 국내에서 대두유와 대두박을 생산하는 대두가공업체의 안정적 대두유 공급이 주요 원인이라고 할 수 있다. 식용유지의 시장규모는 식품공전상 식용유지로 분류된 제품들의 2000년도 출하액으로 보면 약 6,616 억원 정도이다. 한편 유종이 단순했던 가정용 식용유지 시장이 최근 새로워지고 있다. 주로 조리용으로 사용했던 것에서 건강을 생각하는 품목으로 바뀌는 경향이다. 아직은 가정용에서 대두유가 가장 많지만 옥배유나 채종유 더 나아가 건강이미지의 식용유인 홍화유 올리브유 해바라기유등이 증가하고 있는 추세이다. 한편 기존 식용유가 비만의 원인인 것 때문에 기피되던 것에서 새롭게 다이어트용 식용유 제품이 출시되어 시장에 새 바람이 불고 있다. 일본 식용유지 시장규모는 물량으로 172 만톤, 금액으로는 2,786 억엔(약 2조7860 억원) 수준이다. 지난 10년간 증가율은 물량 측면에서 약 $5\%$정도 신장하고 금액으로는 큰 증감이 없었다. 식용유는 조리의 기초 소재로서 안정한 수요를 갖고 있지만 주요 유종인 샐러드유의 가격이 하락하여, 전체적으로 시장이 물량이 증가하면서도 매출액이 신장하지 못하여 시장규모는 축소되었다고 할 수 있다. 일본 식용유지 업계의 제품동향을 보면 거의 모든 업체가 가정용 시장에서 건강 기능성 식용유지를 출시하고 있다는 점이다. 물론 일본은 건강기능성 식품에 대한 제도적인 뒷 받침이 되어 있어 기능성 식품의 시장출시가 용이한 점이 가정용 시장에 큰 영향을 미쳤다고 볼 수 있다. 유지 산업의 고부가가치화를 위해서는 전통적인 산업의 제품과 기술만으로는 달성하기 어렵다. 국내와 일본 식용유지 업계의 경향을 참고해 볼 때 차별화된 식용유지 제품과 기술의 개발이 절실히 필요하다. 앞서 언급한 고부가가치 제품과 기술 관련 사향을 바탕으로 국내 유지분야가 중점적으로 연구할 분야를 선정해 보면 리파제의 고정화 연구, 생물공학 기술을 활용한 효소의 개발과 이를 이용한 유지 가공 기술 연구, 유지성분의 유화 안정화 기술 연구, 식용유지의 선택적 수소경화 기술 연구 트랜스 지방산 저감기술연구, 효소 반응조 설계기술 연구, 지질 분자구조 분석기술 연구 분야 등이 유망하다. 상기와 같은 연구 분야를 육성하기 위해서는 유지 전문 인력의 육성, 해외 네트웍의 구축, 산학연 공동연구 추진, 국가적 차원의 정책 및 지원 등이 절실하다.