• Title/Summary/Keyword: isopropyl

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Effects of Various Salt Concentrations on Physicochermical Properties of Brined Cucumbers for Pickle Process (피클제조를 위한 취청오이의 염농도에 따른 염장중 이화학적 특성)

  • 박용곤;박미원;최인욱;최희돈
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.4
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    • pp.526-530
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    • 2003
  • Changes of physicochemical properties of brined cucumber were investigated in the samples mixed cucumber and water at 1 : 1.2 ratio in various salt concentrations from 15 to 30%. As salt concentrations in brine solutions were increased, cucumber was getting constricted and decreased in the size of diameter. Salt concentrations of brined cucumber were reached an equilibrium after 30 days of brine storage. When cucumber was preserved at 30% salt concentration, pH was gradually decreased until 60 days of brine storage. When cucumber was preserved in 15% salt solution, the yellowness on the surface of cucumber peels was the most intense among the groups. Among the groups preserved by more than 20% of salt, no difference was observed in intensity of yellowness after 30 days of brine storage. The absorbances of isopropyl alcohol extracts at 410, 505, 607, and 665 nm were different from those of raw cucumbers. Regardless of salt concentration, the hardness of cucumber was increased as preservation was prolonged except the group preserved in 15% salt solution.

Fabrication of Tin(IV) Oxide Film by Sol-gel Method (졸겔법을 이용한 산화주석 박막의 제조에 관한 연구)

  • Lee Seung-Chul;Lee Jae-Ho;Kim Young-Hwan
    • Journal of the Korean Electrochemical Society
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    • v.3 no.1
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    • pp.15-18
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    • 2000
  • Transparent conducting tin (IV) oxide thin films have been studied and developed for the electrode materials of solar cell substrate. Fabrication of tin oxide thin films by sol-gel method is process development of lower cost photovoltaic solar cell system. The research is focused on the establishment of process conditions and development of precursor. The precursor solution was made of tin isopropoxide dissolved in isopropyl alcohol. The hydrolysis rate was controlled by addition of triethanolamine. Dip and spin coating technique were applied to coat tin oxide on borosilicate glass. The resistivity of the thin film was lower than 0.01-cm and the transmittance is higher than $90\%$ in a visible range.

A Study on Developing of Soldering Flux (납땜 플럭스 개발에 관한 연구)

  • 이통영
    • Fire Science and Engineering
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    • v.14 no.2
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    • pp.33-38
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    • 2000
  • Flux, essentially used in soldering process of PCB (Printed Circuit Board) in electronics industry, contains IPA (Isopropyl alcohol) and methanol, which are highly inflammable and explosive. Hazard Chemical Controlling Law classified methanol as toxic material and Environmental Law classified methanol as VOC (Volatile Organic Compound). So there have been pressing needs of developing substitutes for the existing Flux. New solvent which is non-flammable and main component is DCP having same specific character of the existing Flux. It's been combirated with proper composition ratio adding stabilizer. As a result, it relieved working Environment Allowance thickness 200 ppm to 470 ppm, chance of not been soldered 0.083% to 0%, spread 85% to 87%, power saving resistance 1.0$\times$$10^{12}$$\Omega$ to 6.9$\times$$10^{12}$$\Omega$, which means a lot better than the existing Flux. Therefore, Flux confirmed the chance of improving productivity, safety, environment safety and quality. Also, Flux got a satisfied result after product quality test and product reliability test.

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Flavour Improvement of Soybean Pastes by the Addition of Bacillus licheniformis and Saccharomyces rouxii (Bacillus licheniformis 와 Saccharomyces rouxii 첨가에 의한 된장의 풍미향상)

  • Shin, Soon-Young;Kim, Young-Bae;Yu, Tae-Jong
    • Korean Journal of Food Science and Technology
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    • v.17 no.1
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    • pp.8-14
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    • 1985
  • In order to give the unique flavour of traditional Doenjang (Korean-style soybean paste) to commercially manufactured soybean paste, the addition of Bacillus licheniformis and Saccharomyces rouxii was tried and their influences were investigated. The addition of B. licheniformis and S. rouxii in soybean paste decreased the content of reducing sugars. By the addition of B. licheniformis, the contents of amino type nitrogen and titrable acidity were increased. The content of ammoniacal nitrogen was reduced and ethyl alcohol production was increased by the addition of S. rouxii. The viable counts of molds showed the decreasing tendency during the aging and it was accelerated by the addition of B. licheniformis and S. rouxii. Acetaldehyde, acetone, ethylacetate, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and isopropyl alcohol were detected from the vapor of all tested ripen soybean pastes, while in a traditional Doenjang, isoamyl alcohol and isobutyl alcohol were not. The B. licheniformis and S. rouxii added sample showed richest free amino acid content. In organoleptic test the B. licheniformis and S. rouxii added sample showed the most excellent overall acceptability.

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A Study on the Process in MMA/IPMI/Styrene Terpolymerization (MMA/IPMI/Styrene 삼원공중합 공정연구)

  • Park Jong-Kyoung;Yoon Sung-Cheol;Jin Jung-Il;Lee Chang-Jin
    • Polymer(Korea)
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    • v.30 no.4
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    • pp.326-331
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    • 2006
  • MMA(methyl methacrylate)/IPMI(N-isopropyl maleimide) copolymers are one of the well known heat resistant materials for POF(plastic optical fiber). However, because of the large difference in the reactivity ratio between MMA and IPMI$(r_1/r_2=1.72:0.17)$, the compositional drift occurs during the polymerization process which causes the deterioration of the physical properties of these copolymers. In this paper, we report that the compositional drift of the copolymer could be reduced by the addition of styrene (St) which increased the reactivity of IPMI in the MMA/IPMI copolymerization system and conversion was also increased by 1.5 or 2 times. The MMA/IPMI/St terpolymer had higher refractive index than the MMA/IPMI copolymer which depended on the contents of sytrene.

Calcitonin Transport through Skin Using Iontophoresis

  • Kim, Kyung-Min;Oh, Seaung-Youl
    • Journal of Pharmaceutical Investigation
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    • v.41 no.1
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    • pp.9-17
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    • 2011
  • The objective of this work is to study transdermal delivery of calcitonin using iontophoresis and to evaluate various factors which affect the transdermal transport. We have studied the effect of polarity, current density, drug concentration, penetration enhancers (isopropyl myristate [IPM] and ethanol) and laser treatment on transdermal flux and the results were compared. We also investigated the iontophoretic flux from microemulsions containing calcitonin together with oleic acid (OA) or IPM. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell and full thickness hairless mouse skin. Anodal delivery at pH 3.0 was much larger than cathodal and passive delivery, due to the positive charge of calcitonin. Cumulative amount delivered (CUM) by cathodal or passive delivery was close to zero for 10 hours. The pretreatment of skin by neat IPM markedly increased the CUM anodically. CUM increased as the current density, drug concentration or the duration of IPM treatment increased. Microemulsion containing IPM or oleic acid was prepared and the phase diagram was constructed. CUM also increased when IPM was incorporated into a microemulsion. OA microemulsion showed similar enhancing effect to IPM microemulsion. The delivery of calcitonin from 70% (v/v) ethanol aqueous solution showed a large increase in flux. Laser treatment of skin before flux experiment exhibited about 2 fold increase in total calcitonin amount transported for 12 hours, when compared to that delivered by IPM microemulsion. Based on these results, we have evaluated the possibility of delivering enough amount of calcitonin to reach the therapeutic level. The data suggest that it is highly possible to deliver clinically effective amount of calcitonin using iontophoresis patch with small area (<10 $cm^2$).

The Expression and Functional Analysis of Recombinant Alcohol Dehydrogenase (재조합 alcohol dehydrogenase의 발현 및 기능분석)

  • Kong, Kwang-Hoon;Shim, Eun-Jung;Park, Hee-Joong;Kim, Eun-Ho;Cho, Sung-Hye;Park, Sung-Woo;Kim, Young-Mann
    • Analytical Science and Technology
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    • v.12 no.6
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    • pp.565-570
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    • 1999
  • The alcohol dehydrogenase (ADH) gene from Bacillus stearothermopilus was amplified by the polymerase chain reaction. The amplified DNA was inserted into the expression vector pGEX-KG, and expressed it as a fusion protein with glutathione S-transferase (GST) in E. coli. The recombinant ADH was produced by induction with 1 mM isopropyl-${\beta}$-D-thiogalactopyranoside at $37^{\circ}C$ and purified by glutathione affinity chromatography. The recombinant ADH exhibited high substrate specificity for ethanol. The activity of the recombinant ADH proceeded optimally at pH 9.0 and $70^{\circ}C$. The recombinant ADH was highly stable against high temperature. This thermostable alcohol dehydrogenase can be used for the enzymatic determination of alcohol and for the industrial production of alcohol.

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Solubilization of Talniflumate in Microemulsion Systems (마이크로에멀젼을 이용한 탈니플루메이트의 가용화)

  • Lee, Gye-Won;Cho, Young-Ho;Kim, Hak-Hyung;Kim, Sock-Young;Kim, Do-Kyun;Kim, Eun-Hea
    • Journal of Pharmaceutical Investigation
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    • v.38 no.3
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    • pp.171-176
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    • 2008
  • Talniflumate is a nonsteroidal anti-inflammatory drug (NSAID), which has been used treat of rheumatoid diseases, is insoluble in water, therefore it has low bioavailability after oral administration. The purposes of this study were to prepare O/W or W/O microemulsions for solubilization of poorly water soluble drug, talniflumate and to formulate into other dosage form. For this purpose, we made O/W or W/O microemulsion with oil(soybean oil, IPM), surfactant (Cremophor $EL^{(R)}$, Tween 80) and water or propylene glycol and evaluated solubility of talniflumate. The microemulsion systems were very stable and showed transmittance above 95% without flocculation or aggregation. Especially, the solubility of talniflumate in the formulation B-1 containing 18% of isopropyl myristate and 71% of tween 80 was 10 times higher than that of other O/W microemulsions. The addition of propylene glycol and N-methylglutamine to the fomulation B-1 showed excellent capacity on the solubilization of talniflumate and the percentage was almost 2.0%. These results suggest that the microemulsion system may be promising for the solubility improvement of talniflumate.

Production of Periplasmic Space-Secreted Organophosphorus Hydrolase from Recombinant Escherichia coli for Degradation of Environmental Toxic Organophosphate Compounds (환경 독성 유기인 화합물 분해를 위하여 재조합 대장균에서 세포내 간극으로 분비된 Organophosphorus Hydrolase의 생산)

  • Choi, Suk Soon;Seo, Sang Hwan;Kang, Dong Gyun;Cha, Hyung Joon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.13 no.3
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    • pp.89-96
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    • 2005
  • In the present work, production of organophosphorus hydrolase (OPH) that is secreted in periplasmic space of recombinant Escherichia coli was performed for degradation of environmental toxic organophosphate compounds, paraoxon. The optimal conditions for enhancement of OPH production were 1.0 mM isopropyl-${\beta}$-D-thiogalactopytanoside (IPTG), 0.25 mM $Co^{2+}$, and 0.1 mM ethylenediamine tetraacetate (EDTA). Under these culture conditions, the maximum OPH production was $174Unit/L{\cdot}OD$. In addition, 1 mM of paraoxon was completely degraded by OPH. These results can be used as a bioremediation tool for removal of environmental toxic organophosphate compounds remaining in soil and aquatic environment.

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Numerical Simulation of Inkjet Drop Formation in Piezo Inkjet Head (피에조 잉크젯 헤드의 액적 토출 형상 전산해석)

  • Joo, Youngcheol;Park, Sangkug;Kwon, Key-Si
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.641-647
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    • 2016
  • A drop-on-demand inkjet is used widely for various applications. Therefore, it is important to understand the jetting behavior of the drop from the piezo inkjet. In this study, to predict the jetting behavior, VOF (Volume-of-Fluid) simulation techniques were used and compared with the experimental results. The experimentally measured meniscus movement was used as the input data for the simulation. To verify the simulation, the measured jetting behavior of the mixture fluids of ethylene glycol and IPA (isopropyl alcohol), which has a mixing ratio of 50:50, was used. The numerical simulation of the drop formation using various mixture ratios and its comparison with the measured drop formation confirmed that the proposed method can predict the actual jetting. On the other hand, the satellite drop behavior showed slight differences because the small sized droplet is subject to a more aerodynamic effect during flight because the kinetic energy of the satellite droplet is far smaller than that of the main droplet.