• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.4
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• pp.326-332
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• 2008

In this work CdS films were prepared by using chemical bath deposition, which is simple and inexpensive technique suitable for large deposition area. Annealing in air at different temperatures (300, 350, 400, 450 and $500^{\circ}C$) at constant time of 30 min, also for different times (15, 30, 45, 60 and 90 min) at constant temperature ($300^{\circ}C$) is achieved. X-Ray analysis has confirmed the formation of cadmium oxide (CdO) with slight increase in grain size, shift towards lower scattering angle due to relaxation in the tensile strain for deposition films, and structure change from cubic and hexagonal to the hexagonal. From electrical properties, significant increase in electrical conductivity appeared in samples annealed at $300^{\circ}C$ for 60 min, and at $350^{\circ}C$ for 30 min.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.7
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• pp.1025-1034
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• 2000

Cotton differs from polyester in physical and chemical properties. When cotton/polyester blends are dyed, water-soluble dyes are generally used for cotton and disperse dye for polyester. Thus, two bath or one bath-two step dyeing process are usually accepted. These processes consume more energy and cost compared to a single step process. To save energy and cost, a single step dyeing and finishing is carried out with disperse dyes in the presence of a crossslinking agent. K/S values of the dyed fabrics were determined to examine the dyeing property of cotton, cotton/polyester, polyester fabrics dyed with disperse dyes in the presence of DMDHEU/PEG. The concentration of DMDHEU, molecular weight and concentration of PEG, curing time and curing temperature were varied.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.276-279
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• 2004

The factors affecting Ni-Co alloy electroforming were investigated to determine the optimum bath composition and electroplating parameters, like pH, temperature, and current density, suitable for high speed fabrication of a micro mold with longer lifetime. To obtain alloy deposits having uniform thickness and composition, electroplating parameters were finely tuned with home-made electroforming apparatus. Ni-Co alloy deposits had linearly increased Co with $Co^{2+}$ ion concentration in electroplating bath, and showing $412H_v$ of Victors hardness at $23wt\%$ of Co content. For Ni-Co alloy, sulfonate and diol related organic additives were very effective to alleviate its residual stress and surface roughness. The maximum deposition rate was $106{\mu}m/hr$ at 10ASD and the tensile strength of alloy deposit was 2 times larger than that of Ni only case.

• Applied Science and Convergence Technology
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• v.27 no.2
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• pp.38-41
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• 2018

We demonstrate the growth of a sheet-like ZnO membrane on ZnO nano rod layers. The growth process is composed of 3 steps of ZnO seed formation, ZnO nano rod growth and sheet-like ZnO membrane formation on those nano rods. To confirm the fundamental growth mechanism, the lattice structures of each step were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) measurement. Analysis of the relation between the texture coefficient and the surface shape of the ZnO membrane on the ZnO nano rods shows that the surface morphology of ZnO nano structures can be controlled using the temperature of the growing solution and the concentration of the chemical solution.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.5-9
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• 1995

In the dry-jet-wet-spinning process of a hollow fiber membrane, the polymer solution is pumped into a coaxial tube, jet spinneret. The threadline emerging from the spinneret is stabilized by an internal coagulating medium(liquid or gas) as it emerges from the jet orifice. The nascent hollow thread is further stabilized in a quench bath as shown in Fig. 1. In this scheme, three mechanism of formatiota(temperature gradient, solvent evaporation, and solvent-nonsotvent exchange) can be combined. The changes which promote stabilization often play a dominant role in determining the ultimate fiber wall structure as well. Hence, in pratice, hollow fiber stabilization and development of membrane structure are commonly inseparable. However, fiber dimension(the inside diameter and wall thickness of the hollow fiber) is mainly a rheological problem and is determined by dope pumping rate, spinneret diatance from the coagulation bath, inner coagulant flow rate, and fiber draw-rate. Besides rheological phenomena play a prominent part in the final properties of the hollow fiber.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.34-39
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• 1989

During the preparation of Ssang Wha tea it was observed that the highest yield was obtained when it was extracted with 50% ethanol, of which guantity was added 10 times more then that of Sample. The most effective extraction temperature and time was $90^{\circ}C$ and 8hours on the water bath, which was resulted in saving of production cost. From the HPLC Analysis, it was also observed that product extracted with 50% ethanol give higher yield than that of exfrac ted with water.

• International Journal of Air-Conditioning and Refrigeration
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• v.13 no.1
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• pp.44-50
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• 2005

In the present study, the characteristics of upward bubble flow were experimentally investigated in a liquid bath. An electro-conductivity probe was used to measure local volume fraction and bubble frequency. Since the gas was concentrated at the near the nozzle, the flow parameters were high near the nozzle. In general their axial and radial values tended to decrease with increasing distance. For visualization of flow characteristics, a Particle Image Velocimetry (PIV) and a thermo-vision camera were used in the present study. The experimental results showed that heat transfer from bubble surface to water was largely completed within z = 10 mm from the nozzle, and then the temperature of bubble surface reached that of water rapidly. Due to the centrifugal force, the flow was more developed near the wall than at bubble-water plume. Vortex flow in the bottom region was relatively weaker than that in the upper region.

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.33-41
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• 1997

This paper surveys the extraction condition of polygenetic natural dye, Sappan Wood and the effect of ash to the dyeability and fastness. The appropriate time for extracting Sappon Wood was 1hour. The pH was increased as the amount of ash increase. The pH was nearly invariable according to the time of ash solution, the extracting times and temperature. Absorbance of dyeing fabrics was about 480nm. From the result of K/S value determination of fabrics, 10g/$\ell$ quantity of ash was surfficient for treatment and the amount of Sappon Wood was in 100% o.w.f.. K/S value of fabrics pre-mordanted or post-mordanted were higher than that of fabrics simultaneous mordanted.K/S value was increased as pH of mordanting bath decrease and pre-mordanting and post-mordanting fabrics increased the amount of absorption (K/S value) compared with non-mordanted fabrics. It was found that pH of mordanting bath affected the amount of absorption and color change of dyed fabrics. Light fastness of fabric dyed was very poor and the fastness of fabric dyed was not influenced by the mordanting conditions and methods.

• Journal of the Korean institute of surface engineering
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• v.47 no.5
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• pp.269-274
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• 2014

Electroless plating process as a solution deposition method is a viable means of preparing conductive metal films on non-conducting substrates through chemical reactions. In the present study, the preparation and properties of electroless Ni-plating on flexible silicone rubber are described. The process has been performed using a conventional Ni(P) chemical bath. Additives and complexing agents such as ammonium chloride and glycine were added and the reaction pH was controlled by NaOH aqueous solution. Ni deposition rate and crystallinity have been found to vary with pH and temperature of the plating bath. It was shown that Ni-films having the high crystallinity, enhanced adhesion and optimum electric conductivity were formed uniformly on silicone rubber substrates under pH 7 at $70^{\circ}C$. The conductive Ni-plated silicone rubber showed a high electromagnetic interference shielding effect in the 400 MHz-1 GHz range.

• Journal of fish pathology
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• v.23 no.3
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• pp.293-302
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• 2010

Effects of formalin on removal of Pseudodactylogyrus spp. were examined against naturally infected eel, Anguilla japonica (weight 89.9~96g) at a water temperature of $28^{\circ}$. Prior to experiments for removal of the parasite, the hematological toxicity of formalin bath at 0~500 ppm for 30 min~24 h was assessed by hematocrit values (Ht). Based on the results of Ht, appropriate methods of treatment, concentrations and durations, were examined in the main study. There was no significant (P>0.05) change of Ht in 100 to 200 ppm for 24 h. In contrast, Ht increased significantly (P<0.05) at above 300 ppm. This suggests that physiological damage was caused by formalin bath treating with 300 to 500 ppm. Formalin bath with 100 and 200 ppm for 24 h caused significant decreases (P<0.05) in the infection of the parasite. In conclusion, the 100 ppm formalin for 24 hour-bath was found most recommendable for the effective treatment of Pseudodactylogyrus spp. for the gills of the infected eel because of the median lethal concentration ($LC_{50}$) of formalin to eel; cumulative mortalities were found to be 0 and 13.3%, respectively, following 24 h bathing.