• 한국자원식물학회지
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• 제24권4호
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• pp.461-471
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• 2011

본 연구에서는 조직배양을 통해 은행나무 잎으로부터 캘러스를 유도하였고, 최대 생장량과 항산화능이 우수한 배양조건을 확립하였다. 즉, 은행잎을 이용하여 조직배양한 결과 암과 광조건에서 모두 NAA 첨가 조건이 2,4-D 첨가 조건에 비교하여 양호한 캘러스 생장을 나타냈다. 가장 우수한 캘러스 생장을 나타낸 배양조건은 광조건의 10 ${\mu}M$ NAA와 5 ${\mu}M$ kinetin의 조합 처리시였다. 따라서 현탁배양에서 캘러스의 지속적인 유지를 위한 효과적인 생장조절제는 10 ${\mu}M$ NAA/0.5 ${\mu}M$ BA, 10 ${\mu}M$ NAA/0.5 ${\mu}M$ kinetin으로 나타났다. 또한 은행잎 유래 캘러스 추출물의 항산화능은 광조건에서 10 ${\mu}M$ NAA가 처리된 기본 MS배지에 캘러스를 현탁 배양하였을 때 가장 높게 나타났다. HPLC를 통한 flavonol glycosides를 분석한 결과 10 ${\mu}M$ NAA가 처리된 조건에서 현탁 배양된 녹색 캘러스에서 quercetin dehydrate와 keamperol이 각각 0.556, 0.157 ${\mu}g$/20 ${\mu}l$ 검출되었다. 잎 추출물에 비해 표적물질을 제외한 불순물이 적어 표적물질의 순수생산이 가능할 것으로 기대되며, 특히 keamperol의 경우 기존의 연구보고에 비해 약 7배 높은 함량이 검출되었다.

• 대한금속재료학회지
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• 제49권7호
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• pp.583-588
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• 2011

$Cd_xZn_{1-x}O$ thin films were grown on quartz substrates by using the sol-gel spin-coating method. The mole fraction, x, of the $Cd_xZn_{1-x}O$ thin films was controlled from 0 to 1 by changes in the content ratio of the cadmium acetate dehydrate [$Cd{(CH_3COO)}_2{\cdot}2H_2O$] and zinc acetate dehydrate [$Zn{(CH_3COO)}_2{\cdot}2H_2O$]. The effects of the mole fraction on the morphological, structural, and optical properties of the $Cd_xZn_{1-x}O$ thin films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-visible spectroscopy. The $Cd_xZn_{1-x}O$ thin films exhibited the polygonal surface morphology and their grain size was increased ranging from 42.1 to 63.9 nm with the increase in the mole fraction. It was observed that the absorption bandgap of the $Cd_xZn_{1-x}O$ thin films decreased from 3.25 to 2.16 eV as the mole fraction increased and the Urbach energy ($E_U$) values changed inversely to the optical bandgap of the $Cd_xZn_{1-x}O$ thin films.

• Journal of Information Display
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• 제9권3호
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• pp.8-11
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• 2008

A novel non-alkoxide sol-gel process for synthesizing Ga-doped ZnO thin film on glass was derived for possible use as a transparent electrode in flat-panel displays, using zinc acetate dehydrate as the starting material. The structural and electrical properties of thin films have been characterized as functions of Ga addition and post-heat-treatments. Their carrier density, Hall mobility, and optical transmittance were measured and discussed herein to explain the characteristics of the sol-gel-derived Ga-doped ZnO thin film on glass.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제38차 학술발표대회
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• pp.190-191
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• 2008

In the presence of heat and oxygen, phosphorous compounds decompose to form water vapor and phosphorous oxides. The phosphorous oxides subsequently reat with the polymer matrix and dehydrate it, reforming phosphoric acids. These acids again decompose to reform water vapor and phosphorous oxides. Ultimately as the water available from normal combustion of hydrocarbons diminishes, the phosphorous oxide reat with hydrocarbon fragments to produce a very high melting point char at the interface between the polymer and the heat material. The chars, which contain phosphorous, rapidly dissipate heat energy and lose their glow. This antiglow property of phosphorous compound contributes to its availability as a flame retardant. In this study, the acrylated phosphorous compounds will be prepared and demonstrated as flame retardants.

• 약학회지
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• 제39권4호
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• pp.438-443
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• 1995

Four different pseudopolymorphs of amoxicillin-trihydrate, dehydrate, monohydrate and anhydratewere prepared and characterized by UV spectrophotometry, DSC, and TGA. In vitro dissolution studies of four pseudopolymorphs were carried out in pH 6.8 phosphate buffer at $37^{\circ}C$ by means of a rotating disk method. The effect of four pseudopolymorphs on bioavauability of amoxicillin was studied in healthy 6 subjects using urinary excretion method. The dissolution result was shown in the sequence, trihydrate(95.5%)>monohydrate(83.5%)>anhydrate(67.6%)>dihydrate(15.8%). The urinary excretion rate of anhydrate could not be detected and the dissolution results agreed well with in vivo phannacoldnetic study results. The effects of storage conditions, milling and compression on the pseudopolymorpnc transformation were investigated by thermal methods. The results showed that four pseudopolymorphs were not transformed and they were very stable.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 제3회 심포지움 (분리막 연구의 최신동향)
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• pp.39-55
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• 1995

Modified polycrylonitrile(PAN) membranes were prepared by emulsion or emulsifier-free emulsion polymerization technique. Separation capacity was determined at several operating temperatures(25, 40, 55 and 70 $^{\circ}$C) to dehydrate 56wt% pyridine aqueous solution through modified PAN membranes having different functional groups. All these PAN-based membranes were selective toward water to different degrees depending on the nature of functional groups present in the membranes. Pervaporation characteristics of PAN-based membranes are so different and classified into three categories depending on the type of the functional groups in PAN copolymers. Among PAN-based membranes, the in-situ complex membranes show the best separation capacity over the operating temperatures.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.727-730
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• 2005

The purpose of this study evaluates possibilities of waste phosphogypsum into concerts by steam curing admixture. The waste phosphogypsum is made use of 4 forms(Dehydrate, $\beta$-Hemihydrate, III-Anhydrite and II-Anhydrite) which were changed to in low temperature of calcination. The penetration depth and compressive strength of cement mortar are investigated to evaluate the chloride ion and carbonation resistance. As a result, chloride ion and carbonation resistance of cement mortar admixed with waste phosphogypsum are more excellent than cement mortar contained OPC alone. The internal pores of cement mortar are decreased by using waste phosphogypsum, because the hydrates of ettringite which is denesified in structure is much formed in early ages at steam curing. These densified effect is concluded with improving the resistance to attack of cement mortar including waste phospogypsum.

• 한국전기전자재료학회논문지
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• 제30권7호
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• pp.413-416
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• 2017

We investigated solution-processed indium-yttrium-oxide (IYO) TFTs using apoly (methyl methacrylate) (PMMA) passivation layer. The IYO semiconductor solution was prepared with 0.1 M indium nitrate hydrate and 0.1 M yttrium acetate dehydrate as precursor solutions. The solution-processed IYO TFTs showed good performance: field-effect mobility of $13.13cm^2/Vs$, a threshold voltage of 8.2 V, a subthreshold slope of 0.93 V/dec, and a current on-to-off ratio of $7.2{\times}10^6$. Moreover, the PMMA passivation layers used to protectthe IYO active layer of the TFTs, did so without deteriorating their performance under ambient conditions; their operational stability and electrical properties also improved by decreasing leakage current.

• Biomolecules & Therapeutics
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• 제6권4호
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• pp.417-422
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• 1998

Loxoprofen sodium (sodium 2-[4-(2-oxocyclopentylmethyl)phenyl] propionate dehydrate) is a nonsteroidal antiinflammatory drug of $\alpha$-phenyl propionic acid derivative. To test the bioequivalence of loxoprofen, the pharmacokinetic parameters of new preparation of loxoprofen, LENOX was compared with LOXONIN as a reference drug. Fourteen healthy volunteers were entered to the stydy (Yonsei University College of Medicine, Severance Hospital IRB approval No. 9608). They were administered 60 mg of loxoprofen in 2$\times$2 cross-over design. There was one week of drug-free interval between doses. The blood sample was taken on schedule up to 8 hours, and the plasma concentration loxoprofen was measured by reverse phase high-performance liquid chromatography (HPLC) with UV-detector. There were no significant difference between two preparations when AUC, Cmax, and Tmax were compared by ANOVA. The mean differences of AUC, Cmax, and Tmax were within 20% of the reference drug: the values were 2.22,5.61, and 12.50%, respectively. The confidence limits of AUC and Cmax but not Tmax satisfied the bioequivalence criteria. These results suggest that the tested LENOX is bioequivalent to the reference drug.

• 한국세라믹학회지
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• 제42권4호
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• pp.245-250
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• 2005

단결정 사파이어 (0001) 기판 위에 저가의 초산아연(Zinc Acetate Dehydrate; ZAH) 전구체를 이용하여 초음파 열분해법과 Ar 가스를 이용한 ZnO 박막을 성장시켰다. Thermogravimetry-Differential Scanning Calorimetry(TG-DSC) 초산아연의 열분해 과정을 조사하여 $380^{\circ}C$ 이상에서 ZnO로 분해되는 것을 확인하였다. $380-700^{\circ}C$에서 증착된 ZnO 박막은 모두 ZnO (002), (101) 결정면으로 부터의 회절피크를 보여주고 있었으며, $400^{\circ}C$ 박막의 경우 c-압축 스트레인 ${\Sigma}Z=0.2\%$, 압축 응력 $\sigma=-0.907\;GPa$이 작용하고 있음을 알 수 있었다. 전자 현미경을 이용한 미세 구조의 관찰을 통하여 $380-600^{\circ}C$에서는 초산아연과 ZnO 초미세 입자가 혼합된 aggregate 형태의 결정립을 형성하고 있었으며, nanoblade 형태의 미세구조를 보였다. 한편 $700^{\circ}C$에서 증착된 박막내의 결정립은 찌그러진 육방정계의 형태를 취하고 있으며, 10-25nm 정도의 부결정림 초미세 ZnO 입자로 이루어져 있음을 알 수 있었다. 초미세 입자의 형성을 임의 핵형성 기구(random nucleation mechanism)로 설명하였고, photoluminescence(PL) 측정을 통하여 광 특성을 조사하였다.