• 대한화학회지
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• 제24권3호
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• pp.250-258
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• 1980

여러종류의 자유라디칼들이 이소니트릴에 첨가되어 중간체인 imidoyl 자유라디칼 RN=CR'을 형성한다. 이것은 또한 imine으로부터 imidoyl hydrogen 을 떼어 내는 다음과 같은 반응에 의해서도 생성될 수 있다. RN=C(H)R' ＋ R"${\cdot}{\rightarrow}$ RN=CR' ＋ R"-H 중간체인 imidoyl 자유라디칼은 ${\beta}$-cleavage 및 aton transfer 반응을 통해서 안정된 분자를 형성한다. ${\beta}$-cleavage는 imidoyl 자유라디칼의 구조에 따라서 두개의 다른 방향으로의 반응이 가능하다. Cyanide transfer와 소위 말하는 정상적인 ${\beta}$-cleavage가 그러한 반응들이다. t-Butoxy 자유라디칼이 t-butylisonitrile 7에 첨가되면 중간체인 t-Bu-N=C-O-Bu-t가 생성되는데, 이것은 ${\beta}$-cleavage반응을 통해서 t-butylisocyanate와 t-butyl 자유라디칼을 형성한다. Phenyl 자유라디칼은 7에 첨가되어 중간체인 t-Bu-N=$C-C_6H_5$를 형성하는데 이것은 cyanide transfer 반응을 통해서 benzonitrile과 t-butyl 자유라디칼로 분해된다. 여기서 생성되는 t-butyl 자유라디칼은 다시 7에 첨가하여 intermediate인 자유라디칼 t-Bu-N=C-Bu-t을 형성하고, 이것은 다시 pivalonlonitrile과 t-butyl 자유라디칼로 분해되는데 이러한 반응이 반복되므로 radical chain isomerization을 일으킨다. Silyl 자유라디칼은 7에 첨가되어 t-Bu-N=$C-Si(CH_3)_3$를 형성하고, 이것은 cyanide transfer 반응을 거쳐서 다시 $(CH_3)_3$SiCN과 t-butyl 자유라디칼로 분해된다.

• 한국수정란이식학회지
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• 제28권3호
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• pp.163-168
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• 2013

Embryo transfer (ET) technology is of high importance in modern cattle breeding programs. ET is one step in the process of removing one or more embryos from the reproductive tract of an outstanding donor female and transferring them to one or more recipient females. Embryos also can be produced in the laboratory via techniques such as in vitro fertilization (IVF). But the actual transfer of an embryo is only one step in a series of processes that may include some or all of the following: superovulation and insemination of donors, collection of embryos, isolation, evaluation and short-term storage of embryos, micromanipulation and genetic testing of embryos, freezing of embryos and embryo transfer. Cryopreservation and direct transfer of frozen-thawed embryos is common-place with pregnancy rates near that of fresh embryos. Polymerase chain reaction (PCR) technology is currently being used for sexing embryos, and this technology will be used for "embryo diagnostics" and "embryo genomics" in the future. Although, many limitations and problems remain to overcome, these and other new technologies promise to change livestock breeding drastically in the next decade.

• Korean Chemical Engineering Research
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• 제46권3호
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• pp.604-609
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• 2008

본 연구에서는 세계보건기구의 기준을 만족시키기 위한 포장재 개발을 목적으로 백신 수송용 장방형 포장재 내부열 전달에 대한 모델링 및 시뮬레이션을 수행하고 이를 실험결과와 비교하였다. 장방형의 박스를 구형 박스로 전환하여 구상한 1차원 모델은 냉각공정의 경우에는 실험 결과와 비교적 잘 일치하는 결과를 보였으나, 가열공정에서는 실험결과와 상당한 차이를 보여주었다. 이는 가열공정을 계산할 때, 포장재 외부에서의 경계조건을 적절히 고려해주지 못한 결과로 사료된다. 그러나, 본 연구를 통하여 상전이 물질을 함유한 다층 벽을 통한 열 전달의 문제를 전산 모사할 수 있는 기본적인 알고리즘을 성공적으로 개발할 수 있었다.

• 한국전기전자재료학회논문지
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• 제15권7호
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• pp.615-620
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• 2002

In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidise (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized enzyme electrodes by electropolymerization added some organic solvent, such as ethanol and tetrahydrofuran (THF). The formative seeds of film growth was delayed by adding ethanol. The delay was induced by radical transfer between ethanol and pyrrole monomer. The radical transfer reactions shared the contribution of dopants between electrolyte anion and GOx polyanion. This led to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased.

• Journal of Nutrition and Health
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• 제30권8호
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• pp.930-935
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• 1997

Fatty acid binging proteins(FABP) are distinct but related gene productes which are found in many mamalian cell types. FABP bind long chain fatty acids in vitro. However, their functions and mechanisms of action, in vivo, remain unknown . Also not known is whether all FABP function similaryly in their respective cell types. or whether different FABP have unique functions. The puropose of the present study was to assess whether different members of the FABP family exhibit different structural and function properties. A comparison was made between heart(H-FABP) and liver (L-FABP). The results show that the binding sites of both FABP are hydrophobic in nature, although the L-FABP site is more nonpolar than the H-FABP site. Additionally, the bound ligand experiences less motional constraint within the H-FABP binding site than within the L-FABP binding site. In accordance with these differences in structural properties, it was found that anthroyloxy-fatty acid transfer from H-FABP to membranes is markedly faster than from L-FABP. moreover, the mechanism of fatty acid transfer to phospholipid membranes appears to occur via transient collisional interactions between H-FABP and membranes. In contrast , transfer of fatty acid from L-FABP occurs via an aqueous diffusion mechanism.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 1998년도 춘계학술대회 및 워크숍
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• pp.12-28
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• 1998

The technology of creating transgenic animals has a potential value in improving productivity and disease resistance of animals, gene therapy, drug pharming and production of model animals for certain diseases. Up to date, fairly low success rate of production of transgenic animals and a pronounced variability with respect to the expression of transgenes have been much observed. The mechanisms how to integrate the injected genes with a certain part of the genomes are unknown yet. Many techniques in gene transfer, beside microinjection, have been introduced and explored thus to improve the production efficiency of transgenic animals. In this article, the methods and efficiency of gene-transfer techniques, the detection and preselection of transgenes in embryos by PCR- and GFP-screenings and cloning of preselected transgenic embryos by nuclear transplantation are described and discussed. Some experimental results showed that the early screening and selection of integration of the injected gene with embryonic genome by polymerase chain reaction(PCR) and green fluorecence protein(GFP) were promising methods. Further, the application of nuclear transplantation technology to cloning and multiplication of the positively integrated genes in the cleaving embryos and embryonic cells will be beneficially used for the mass production of transgenic embryos and consequently improving the production efficiency in transgenic animals.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.458-461
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• 2001

IT의 발전으로 산업사회가 정보화를 거쳐 지식화되면서 Value Chain을 규명하여 비효율적인 생산구조를 혁신하는 BPR(Business process Reengineering)이 이루어지고 이를 바탕으로 ERP(Enterprise Resource Planning) 구축이 이루어지고 있다. ERP를 확대하기 위해 SCM(Supply Chain Management)와 CRM(Customer Relationship Management)이 제조업에서 활발히 이루어지고 있다. 그러나, 건설산업에서는 이러한 IT의 접목이 본격화되지 못 하고 있으며 정보화에 대한 인식 또한 미비한 실정으로 정부 주도의 건설CALS와 일부 대기업에서만이 기존의 업무 프로세스를 개선하고 개별 시스템을 통합하는 작업이 이루어지고 있는 실정이다. 대다수의 건설관련 기업은 기존의 조직 및 생산구조에 대한 혁신이 이루어지지 않고 있는 실정이다. 건설산업의 특성상 사업수행 정보(Project Information)와 실적자료(Historical data)의 효율적 관리가 이루어져야 할 것이며, 기존의 기능 중심의 정보흐름을 프로젝트 중심의 정보흐름으로 전환할 수 있는 CIC(Computer Integrated Construction) 및 PMIS(Project Management Information System)의 개발이나 도입이 필요하다. 본 논문은 건설산업에서의 정보화의 문제점을 분석하고 정보의 발생과 흐름을 분석하여 정보화체계 구축의 핵심인 정보의 표준화·동시화·중앙집권화를 이룰 수 있는 방안을 제시하고자 한다.

• Journal of Korea Trade
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• 제25권1호
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• pp.152-168
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• 2021

Purpose - This paper has an objective to suggest reasonable criteria in choosing Incoterms 2020 rules for efficient and effective logistics management in that the Incoterms rules affect not only the rights and obligations of the parties to the sales contract but also the control and management of logistics system and transaction costs in the transaction. Design/methodology - An analysis of the various factors is needed to assess the positive or negative impact on global value chain in choosing Incoterms rules from a total logistics view. This study analyzes the impact of which the content of individual incoterms rules can have on the operation of international logistics systems under the global value chain from a strategic perspective to suggest reasonable criteria for selection of Incoterms rules depending on the transaction situation. Findings - Results of this study shows that consideration of various aspects which includes the characteristics of the products, logistics capabilities, infrastructure, transaction volume, operational cost, customs regulations, tax and accounting should be reflected in choosing the appropriate Incoterms rules. Therefore, in order to minimize the total cost and improve logistics performance, it may be helpful to develop a decision support model which allows users to select appropriate Incoterms rules based on various influencing factors. Originality/value - This Study is different from previous research which has mainly focused on the rights and obligations of the parties to the transaction regarding the transfer of risks and costs under the Incoterms. In addition, this study has significance in that it provides implications for export and import companies that can be able to use Incoterms as a strategic tool to efficiently manage the global value chain and improve supply chain performance.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2679-2683
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• 2014

Mechanisms underlying the impacts of interactions between carbon nanoparticles (CNPs) and ionic liquids (ILs) on the physicochemical behavior of CNPs need to be more full worked out. This manuscript describes a theoretical investigation at multiple levels on the interactions of fullerene $C_{60}$ with 21 imidazolium-based ILs of varying alkyl side chain lengths and anionic types and their impacts on $C_{60}$ dispersion behavior. Results show that ${\pi}$-cation interaction contributed to mechanism of the $C_{60}$-IL interaction more than ${\pi}$-anion interaction. The calculated interaction energy ($E_{INT}$) indicates that $C_{60}$ can form stable complex with each IL molecule. Moreover, the direction of charge transfer occurred from IL to $C_{60}$ during the $C_{60}$-IL interaction. Quantitative models were developed to evaluate the self-diffusion coefficient of $C_{60}$ ($D_{fullerene}$) in bulk ILs. Three interpretative molecular descriptors (heat of formation, $E_{INT}$, and charge) that describe the $C_{60}$-IL interactions and the alkyl side chain length were found to be determinants affecting $D_{fullerene}$.

• Applied Biological Chemistry
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• 제36권6호
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• pp.557-561
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• 1993

Polyethylene glycol(PEG)법 또는 electroporation법으로 제라니움 원형질체에 neomycin phosphotransferase II(nptII) 유전자를 옮기고, 세포내에 도입된 nptII DNA의 존재유무와 발현여부를 조사하였다. Polymerase chain reaction(PCR)을 이용하여 검토한 결과, PEG법을 사용했을 때나 electroporation법을 사용했을 때 모두 세포내에 도입된 nptII DNA가 있음이 확인되었다. 또 이들 세포의 추출물을 전기영동하여 neomycin phosphotransferase 활성을 조사한 결과, 효소활성을 보이는 band가 검출되어 marker gene 으로 도입된 notII 유전자가 세포내에서 발현된다는 것이 확인되었다.