• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.66-67
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• 2020

The synthesis of stearic acid composite phase change material (PCM) was investigated and the samples produced were characterized for use in latent heat storage, using a simple chemical sol-gel process. The PCM was encapsulated to tetraethyl orthosilicate by various preparation ratios of stearic acid (5, 10, 15, 20, 30 and 50%). Fourier transformation infrared spectroscope (FT-IR) and X-Ray diffraction (XRD) were performed to determine the chemical structure and crystalloid phase of the microencapsulated PCM. SATEOS1 (5%) shows the best proportion for the PCM. With the presence of stearic acid as core materials and SiO2 as the supporting materials, it does not show any chemical reaction between both of them. SATEOS1 shows promising potential for thermal energy storage as it shows a better encapsulation efficiency and good thermal stability.

• Advances in nano research
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• v.2 no.1
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• pp.69-76
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• 2014

We have obtained opal-like photonic crystals based on opals and inverted opals exhibiting a shift of the selective reflection band toward longer and shorter wavelengths with respect to the diffraction band of the initial opal consisting of $SiO_2$ spheres. The contribution of frames forming three-dimensional periodic structures and that of fillers to the spectral arrangement of the diffraction bands has been determined.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4191-4194
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• 2011

Sodium periodate ($NaIO_4$) and potassium iodide (KI) in aqueous ammonia has been used for the one-pot synthesis of nitriles from the corresponding aldehydes and alcohols in moderate to good yield. This transformation, proceeds via an in situ oxidation- imination-aldimine oxidation sequence.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.281-281
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• 2005

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.9-10
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• 2003

• YAKHAK HOEJI
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• v.37 no.6
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• pp.555-560
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• 1993

Methyl 3-[(phenylsulfonyl)methyl]-1, 4, 8-trimethoxy-2-naphthoate(7) preparad by 3 steps was condensed with 5-ethyl-2-cyclohexen-1-one(8) to afford the teracyclic aromatic ring system compound 10, which was stepwise converted into the precursor of 11-Deoxy-$\beta$-rhodomycinone by means of various functional groups transformation.

• Bulletin of the Korean Chemical Society
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• v.3 no.2
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• pp.76-78
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• 1982

Ethanolic tetracarbonylhydridoferrate solution combined with glutaraldehyde is a very effective reducing agent for the selective transformation of two moles of secondary amines into pentane-1,5-diamine derivatives. A variety of aliphatic secondary amines react with ferrate-glutaraldehyde at room temperature under carbon monoxide to give the corresponding N-substituted pentane-1,5-diamines in reasonable yields.

• Journal of Environmental Science International
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• v.17 no.11
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• pp.1273-1279
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• 2008

This study examined the catalytic destruction of 1,2-dichlorobenzene on ${V_2}{O_5}/TiO_2$ nanoparticles. The ${V_2}{O_5}/TiO_2$ nanoparticles were synthesized by the thermal decomposition of vanadium oxytripropoxide and titanium. The effects of the synthesis conditions, such as the synthesis temperature and precursor heating temperature, were investigated. The specific surface areas of ${V_2}{O_5}/TiO_2$ nanoparticles increased with increasing synthesis temperature and decreasing precursor heating temperature. In addition, the removal efficiency of 1,2-dichlorobenzene was promoted by a decrease in heating temperature. However, the removal efficiency of 1,2-dichlorobenzene was decreased by an anatase to rutile phase transformation at temperatures $1,300^{\circ}C$.

• The Transactions of the Korea Information Processing Society
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• v.6 no.7
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• pp.1919-1928
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• 1999

There are no standard language for the specification of speed-independent circuits because existing specification methods are designed appropriately to each synthesis methodology. This paper suggests a method of using VHDL, a standard hardware description language, for the specification and synthesis of speed-independent circuits. Because VHDL is a multi-purpose language, we define a subset of VHDL which can be used for the synthesis. We transform the VHDL description into a signal transition graph and then synthesize speed-independent circuits by using a previous synthesis algorithm which uses a signal transition graph as the specification method. We suggest a systematic transformation method which transforms each VHDL statement into a partial signal transition graph and then merges them into a signal transition graph. This work is a step towards to the development of an integrated framework in which we can utilizes the existing CAD tools based on VHDL. Also, this work will enable a easier migration of the current circuit designers into asynchronous circuit design.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.275-279
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• 2005

Tah tasai chinese cabbage (Brassica campestris var. narinosa), a vegetable plant popularly consumed as several-days-old seedlings in oriental countries, can be easily cultivated using a simple appliance. We demonstrated that Agrobacterium-mediated transformation via vacuum infiltration (agroinfiltration) resulted in a successful transient GUS gene expression in tah tasai chinese cabbage seedlings. Pre-germinated seeds were found to be more susceptible to Agrobacterium infection than one-day-old or two-days-old seedlings. We also demonstrated that hydrogen peroxide (HPO) treatment increased GUS expression especially for two-days-old seedlings. In ELISA using seedlings transformed with hepatitis B surface antigen (HBsAg) DNA by agroinfiltration, HBsAg protein synthesis increased more than two folds by HPO treatment to two-days-old seedlings in comparison to the mock-treated pre-germinated seeds.