• 한국염색가공학회지
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• 제11권4호
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• pp.1-7
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• 1999

Urethane-acrylate propelymers for secondary coating of optical fiber and high - performance material were prepared from the 4,4'-diphenylmethane diisocyanate(MDI), poly(tetramethylene oxide)glycol(PTMG, Mw 650 or 1000), 1,6-hexanediol(HD), 2-hydroxyethyl acrylate(HEA), and dibutyltin dilaurate as a catalyst. UV-Curable polyurethane acrylates were formulated from the urethane-acrylate prepolymers, three types of reactive diluents(DTs) having mono-, di-, and trifunctional-phenoxyethyl acrylate(PEA), hexanediol diacrylate(HDDA), and trimethylolpropane triacrylate(TMPTA), and 1-hydtoxycyclohexyl phenyl ketone(Irgacure 184) as a photoinitiator. The UV-cured films of polyurethane acrylates were obtained by curing using a medium-pressure mercury lamp(U W/cm, $\lambda_{max}=365\;nm)$. In this work, the effects of molecular weights of polyol and diol with low molecular weight into polymer chain on mechanical and dynamic mechanical properties of UV-cured polyurethane acrylates were studied. The structure and properties of the films obtained from the UV photopolymerization of urethane-acrylate prepolymer were investigated by FT-IR spectroscopy, dynamic mechanical measurement, tensile testing, and X-ray diffractometry.

• 접착 및 계면
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• 제18권4호
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• pp.159-165
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• 2017

본 연구에서는 반응성 희석제로 사용되는 BA의 함량에 따른 자외선 경화형 폴리우레탄 아크릴레이트 수지를 제조하여 수지의 열적 기계적 성질, 접착강도, 굴곡성을 확인하였다. BA의 함량이 40% 이상으로 증가할수록 Polyol의 Tg와 아크릴 수지의 Tg가 분리되어 나타난 것을 DSC로 통해 확인하였다. 또한 BA의 함량이 증가할수록 아크릴 수지의 낮은 기계적인 물성이 주도적으로 발현되어 인장강도와 신장률, 접착강도가 감소하는 것으로 나타났다. 굴곡성을 평가한 결과 BA의 함량이 40%인 경우 경도가 낮으면서 다른 수지에 비해 Tm이 낮아 굴곡성이 우수한 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제40권6호
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• pp.363-366
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• 2010

Identification of compounds that function as P-glycoprotein (P-gp) substrates or inhibitors can facilitate the selection and optimization of new drug candidates. The purpose of this study is to optimize the experimental conditions for in vitro P-gp assay using LLC-GA5 cells, which is a well-known transformant cell line derived by transfecting LLC-PK1 with human MDR1. The amount of rhodamine123 transported by the LLC-GA5 and LLC-PK1 cells was evaluated under the following experimental conditions: 3 different types of transport media, colchicine pretreatment or nontreatment of the cells in the culture media, and with and without poly-L-lysine coating of the culture plates. The assay sensitivity was found to considerably differ depending on the diluents used in the transport media. P-gp-mediated transport in LLC-GA5 cells was most clearly characterized in the Hanks' balanced salt solution based transport media. The sensitivity of P-gp-mediated transport was not changed by colchicine pretreatment or poly-L-lysine coating of the culture plates.

• 한국양식학회지
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• 제12권1호
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• pp.57-62
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• 1999

숭어 정액의 냉장 및 냉동보존시 적합한 희석액을 선정하고, 알에 대한 수정률을 평가하였다. 비보존 숭어 정자의 머리는 공모양으로 직경 $1.26{\pm}0.08 \{mu}textrm{m}$, 길이 $1.06{\pm}0.07 \{mu}textrm{m}$ 였으며, 과립상의 염색질을 가지고 있었다. 숭어 정자의 냉장보존시($0^{\circ}C$, 10일간) 희석액으로는 동종의 혈정이 가장 높은 정자활성을 나타냈으며, egg-tris, 0.1M, 0.3M 및 0.5M glucos에서는 활성이 서로 비슷하였다. 또한 동해방지제로 10% DMSO, 희석액으로 MFRS를 사용하여 냉동보존한 후 해동시켰을 때 대조구와 유사한 수정률을 보였다. 냉동보존 후 해동시킨 일부 정자 중에서는 세포막이 이탈되거나 소실되는 구조적 변화를 나타냈다.

• 한국수정란이식학회지
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• 제11권2호
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• pp.159-166
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• 1996

본 연구는 돼지 액상정액을 인공수정용 100ml 플라스틱 병에 보존하면서 BF5희석액과 Butschwiler 희석액 간에 보존 온도별 차이를 조사하고, BF5 희석액에서의 글리세롤 농도의 효과를 조사하여 돼지 액상정액을 좀더 장기간 사용할 수 있는 방법을 찾고자 실시하였다. 돼지 액상정액을 5$^{\circ}C$ 냉장고에 보존하면서 조사한 바에 의하면, 37$^{\circ}C$에서 0.5 및 2시간 배양후의 정자운동성은 전체 보존기간동안 BF5 희석액이 Butschwiler 희석액보다 유의하게 (P<0.05) 높게 나타났고, 정상첨체비율은 두 희석액간에 차이가 없었다. 돼지 액상정액을 15$^{\circ}C$에 보존하면서 조사한 바에 의하면, 3일부터 7일 보존시 까지 정자운동성과 정상첨체비율에 있어서 Butschwiler 희석액이 BF5 희석액보다 유의하데 높게 나타났다. BF5 희석액을 이용한 돼지 액상정액의 글리세롤 농도의 효과에 있어서는 최종 글리세롤 농도가 0, 2, 3, 및 5% 보다 1%일 때 가장 높은 정자운동성과 정상첨체비율을 나타내었다. 분만율, 복당 생존자돈수 그리고 출생시 평균 생시체중은 BF5 희석애과 Butschwiler 희석액간에 차이가 없었다. 이상의 연구 결과를 종합해 볼 때 BF5 희석액을 5$^{\circ}C$에서 Butschwiler 희석액은 15$^{\circ}C$에서 6-7일 동안 돼지 액상정액을 보존할 수 있었다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.209-213
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• 2006

Relationship between printability and rheological properties of UV flexographic (flexo) inks were investigated. UV flexo suspensions of carbon black in liquid medium having various binding materials such as acylate pre-polymer, di/multi-functional monomer, and diluents, were used as sample inks. Inks were characterized on a rheometer in terms of steady and dynamic behaviors. To understand the rheological properties of UV flexo inks, we must determine the specific rheological properties of chemical and/or physical interactions of their components (pigments, functional monomers, and pre-polymers). In particular, we discussed the influence of multi-functional monomers and the relationship between the rheological properties and transient networks formed by carbon black. In this study, we investigated the interrelationships between rheological properties of UV flexo inks and chemical and/or physical interactions of their components. To investigate correlations between the printability and the rheological behaviors induced by interfacial interactions between ink compositions, we carried out rheological tests of UV ink suspensions. The results were compared with printing tests so as to find out the relationship between printability and rheological properties of ink.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3286-3297
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• 2021

The released hydrogen can be ignited even with weak ignition sources. This emphasizes the importance of the hydrogen flammability evaluation to prevent catastrophic failure in hydrogen related facilities including a nuclear power plant. Historically numerous attempts have been made to determine the flammability limit of hydrogen mixtures including several diluents. However, no analytical model has been developed to accurately predict the limit concentration for mixtures containing radiating gases. In this study, the effect of H₂O and CO₂ on flammability limit was investigated through a numerical simulation of lean limit hydrogen flames. The previous flammability limit model was improved based on the mechanistic investigation, with which the amount of indirect radiation heat loss could be estimated by the optically thin approximation. As a result, the sharp increase in limit concentration by H₂O could be explained by high thermal diffusivity and radiation rate. Despite the high radiation rate, however, CO₂ with the lower thermal diffusivity than the threshold cannot produce a noticeable increase in heat loss and ultimately limit concentration. We concluded that the proposed mechanistic analysis successfully explained the experimental results even including radiating gases. The accuracy of the improved model was verified through several flammability experiments for H₂-air-diluent.

• Journal of Oral Medicine and Pain
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• 제44권1호
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• pp.11-15
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• 2019

Purpose: The aim of this study was to compare the potency-stabilizing effects of two different diluents of botulinum toxin A (10% dextrose solution and 0.9% saline). Methods: A mouse lethality bioassay was undertaken. Ninety mice were divided into experimental and control groups which received varying dosages in subgroups of 10. The experimental group was injected with botulinum toxin A diluted with 10% dextrose solution and the control group was injected with botulinum toxin A diluted with 0.9% saline. A 72 hours after intraperitoneal injection, the number of dead mice was counted to confirm median lethal dose ($LD_{50}$) of each group. Results: The value of $LD_{50}$ in the experimental group was approximately 0.131 mL (1.31 U) and the value of $LD_{50}$ in the control group was approximately 0.107 mL (1.07 U). The potency preservation rate of the experimental group was estimated to be 93.5% and that of the control group was estimated to be 76.3%. Conclusions: Dilution with 10% dextrose solution displayed less potency loss than 0.9% saline.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2836-2846
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• 2020

During severe nuclear power plant (NPP) accidents, a H₂/CO mixture can be generated in the reactor pressure vessel by core degradation and in the containment as well by molten corium-concrete interaction. In spite of its importance, a state-of-the-art methodology predicting H₂/CO combustion risk relies predominantly on empirical correlations. It is therefore necessary to develop a proper methodology for flammability evaluation of H₂/CO mixtures at ex-vessel phases characterized by three factors: CO concentration, high temperature, and diluents. The developed methodology adopted Le Chatelier's law and a calculated non-adiabatic flame temperature model. The methodology allows the consideration of the individual effect of the heat transfer characteristics of hydrogen and carbon monoxide on low flammability limit prediction. The accuracy of the developed model was verified using experimental data relevant to ex-vessel phase conditions. With the developed model, the prediction accuracy was improved substantially such that the maximum relative prediction error was approximately 25% while the existing methodology showed a 76% error. The developed methodology is expected to be applicable for flammability evaluation in chemical as well as NPP industries.

• Parasites, Hosts and Diseases
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• 제60권3호
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• pp.201-205
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• 2022

Babesia microti is one of the most common causative agents of babesiosis. A sensitive and rapid detection is necessary for screening potentially infected individuals. In this study, B. microti cytochrome c oxidase subunit I (cox1) was selected as the target gene, multiple primers were designed, and optimized by a recombinase-aided amplification (RAA) assay. The optimal primers and probe were labeled with fluorescein. The sensitivity of fluorescent RAA (fRAA) was evaluated using gradient diluents of the cox1 recombinant plasmid and genomic DNA extracted from whole blood of B. microti infected mice. The specificity of fRAA was assessed by other transfusion transmitted parasites. The analytical sensitivity of the fRAA assay was 10 copies of recombinant plasmid per reaction and 10 fg/µl B. microti genomic DNA. No cross-reaction with any other blood-transmitted parasites was observed. Our results demonstrated that the fRAA assay would be rapid, sensitive, and specific for the detection of B. microti.