• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1394-1397
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• 2006

Polymer Dispersed Liquid Crystal (PDLC) films, of which the liquid crystal has negative dielectric anisotropy, were prepared from the phase separation between MJ001317 and a variety of compositions of resins by common polymerization induced phase separation method. In this work, the effects of resin compositions have been systematically investigated and it was found that the morphology and size of droplet, which is closely related to electro-optic properties, mainly depend on the rate of polymerization and cross-linking density for each resin composition. The reverse mode PDLC films from this newly developed formulation containing TPGDA/EHA/HMPPO showed the good off-state transmittance, contrast ratio (19/1), and relatively low driving voltage(10V).

• Journal of Electrochemical Science and Technology
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• v.8 no.3
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• pp.215-221
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• 2017

The electroless plating process largely consists of substrate cleaning, seed formation (activator formation), and electroless plating. The most widely used activator in the seed formation step is Pd, and Sn ions are used to facilitate the formation of this Pd seed layer. This is problematic because the Sn ions interfere with the reduction of Cu ions during electroless plating; thus, the Sn ions must be removed by a hydrochloric acid cleaning process. This method is also expensive due to the use of Pd. In this study, Cu electroless plating was performed by forming a seed layer using a silver nanosol instead of Pd and Sn. The effects of the Ag nanosol concentration in the pretreatment solution and the pretreatment time on the thickness and surface morphology of the Cu layer were investigated. The degrees of adhesion to the substrate were similar for the electroless-plated Cu layers formed by conventional Pd activation and those formed by the Ag nanosol.

• Korean Journal of Materials Research
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• v.17 no.8
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• pp.433-436
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• 2007

Nano-structured polyaniline have been synthesized by interfacial polymerization method at room temperature. An aqueous solution of aniline in chloroform and another solution of ammonium peroxydisulfate in doping acid were prepared at different times terminated with methanol at room temperature. SEM, UV-vis were used to characterize the polyaniline with regard to their morphology and structure. The diameter and length of polyaniline can be controlled by the reaction time. Nano-structured polyaniline were found to have superior sensitivity for volatile organic compounds(VOCs). As the reaction time to increase from 30minute to 2hours the sensitivity were decreased to VOCs vapors. The sensitivity of Nano-structured polyaniline sensor appeared to VOCs better than the sensitivity of chemical synthesis sensors. The sensitivity of Nano-structured polyaniline sensor improved benzene vapors.

• Macromolecular Research
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• v.16 no.5
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• pp.404-410
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• 2008

In order to obtain 'value added products' from polypropylene (PP)/waste ground rubber tire powder (WGRT) composites, PP/WGRT microcellular foams were prepared via supercritical carbon dioxide. The effects of blend composition and processing condition on the cell size, cell density and relative density of PP/WGRT micro-cellular composites were studied. The results indicated that the microcellular structure was dependent on blend composition and processing condition. An increased content of waste ground rubber tire powder (WGRT) and maleic anhydride-grafted styrene-ethylene-butylene-styrene (SEBS-g-MA) reduced the cell size, and raised the cell density and relative density, whereas a higher saturation pressure increased the cell size, and reduced the cell density and relative density. With increasing saturation temperature, the cell size increased and the relative density decreased, whereas the cell density initially increased and then decreased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.46-53
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• 2003

Effects of electric force on the morphology and growth of aggregates were studied experimentally. Nano-sized NaCl particles were supplied to a flame to perform the unipolar charging state. This electric precursor did not modify a temperature profile of the flame. The morphology of aggregates was measured by TEM image processing technique and the light scattering technique. In the unipolar charged state, the fractal dimension of aggregates was smaller than that of' the electrically neutral state. This result was in good agreement with our previous numerical simulations.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.5
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• pp.710-715
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• 2002

The spherical nonagglomerated and uniform nanometer-size SiO$_2$particles are synthesized by the injection of TEOS vapor, irons and reaction gas in a furnace. Ions are generated by corona discharge and these ions charge SiO$_2$particles. As a result, spherical, nonagglomerated and ultrafine particles are generated in various conditions. Their morphology, charging portion and size distribution are examined by using TEM, ESP and SMPS. As the applied voltage of electrode changes from 0 to 5.0 kV, it is observed that the melon diameter of SiO$_2$particle decreases from 94 nm to 42 nm.

• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.11-17
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• 2013

To investigate the effects of co-solvents on the morphology of nano-scale zein materials, zein solutions were electrospun with different co-solvent ratios of EtOH/$H_2O$. Different zein solution concentrations were used to study the effects of the zein content on the electrospun materials. The resulting electrospun materials were all characterized using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The diameters of the electrospun nanoparticles and nanofibers were found to increase when increasing the EtOH ratio at certain zein concentrations. Furthermore, increasing the zein content changed the morphology of the electrospun materials from nanoparticles to nanofibers.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.65-65
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• 2015

• Transactions on Electrical and Electronic Materials
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• v.7 no.5
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• pp.257-261
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• 2006

Nano-structured carbon nitride $(CN_x)$ films were prepared by reactive RF magnetron sputtering with a DC bias at various deposition conditions, and the physical and electrical properties were investigated. FTIR spectrum indicated an ${alpha}C_3N_4$ peak in the films. The carbon nitride film deposited on Si substrate had a nano-structured surface morphology. The grain size was about 20 nm and the deposition rate was $1.7{\mu}m/hr$. When the $N_2/Ar$ ratio was 3/7, the level of nitrogen incorporation was 34.3 at%. The film had a low dielectric constant. The metal-insulator-semiconductor (MIS) capacitors that the carbon nitride was deposited as insulators, exhibited a typical C-V characteristics.

• Carbon letters
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• v.12 no.2
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• pp.102-106
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• 2011

Carbon nanotubes (CNTs) have been synthesized by ferrocene-catalyzed pyrolysis of toluene. The influences of the experimental conditions on the morphology and microstructure of the product have been analyzed. To find the proper temperature for synthesis of CNTs, the experiment was performed in a temperature range from 800 to $1100^{\circ}C$. From content variation of ferrocene and thiophene as the catalyst, morphological change of carbon nanotubes has been observed. Also, the influence of the gas ratio of hydrogen and argon on the nanotube samples was analyzed by scanning electron microscopy and transmission electron microscopy.