• Korean Chemical Engineering Research
• /
• v.50 no.1
• /
• pp.118-127
• /
• 2012

TiN or Ti/TiN was coated on stainless steel as bipolar plate in polymer electrolyte membrane fuel cells (PEMFCs) to improve their corrosion resistance and electric conductivity, and their properties were examined under fuel cell operating condition. After 200 hours operation, the behaviors for the corrosion, crack and dissolution of coating layer were investigated by various techniques. The corrosion and exfoliation of coating layer were considerably generated except for SUS316L-Ti/TiN after fuel cell operation even if the electric conductivity and corrosion resistance of coated stainless steel bipolar plates were improved. The adoption of Ti layer between TiN layer and the surface of stainless steel enhanced the adhesion of TiN layer and decreased the possibility of corrosion by the increase of coating layer.

• Korean Chemical Engineering Research
• /
• v.55 no.6
• /
• pp.830-836
• /
• 2017

Hydrophilic coating solutions were prepared by reacting a silane coupling agent, GPTMS (3-glycidoxypropyl trimethoxysilane) with colloidal silica. Hydrophilic coating films were also obtained by depositing the hydrophilic coating solutions on polycarbonate substrates by spin-coating and subsequently by thermal curing at $120^{\circ}C$. During this process, the effect of average particle sizes of colloidal silica was studied on the properties of coating films. As a result, coating film, prepared from colloidal silica with average particle size of 25 nm, showed a low contact angle of $20^{\circ}$ and a good pencil hardness of H. On the other hand, coating films, prepared from colloidal silica with average particle sizes of 15 nm and 45 nm, exhibited high contact angles of $27^{\circ}$ and $36^{\circ}$ and pencil hardness of H and B, respectively.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.5
• /
• pp.209-216
• /
• 2020

As depository system for negotiation or reimbursement to the victim in criminal case is reflected to consideration for diminishing punishment and hence, it is very important in the process. According to the current law, one needs to fill out victim's personal information such as name, address, and ID number for processing depository. However, if the victim is sexual violence victim, all the personal information is covered up becoming anonymous. Therefore, it becomes difficult for the accused person to get necessary information. Such covering up action is to prevent further second damage that may be caused such as threatening for the negotiation whereas victim has no willingness to forgive the accused. However, even if the accused person regrets his/her crime and make reimbursement to the victim, as they have no personal information on the victim it becomes impossible for them to make the depository. If we apply ESCROW system here it will allow victims to avoid any direct contact with the accused person as well as preventing any privacy disclosure. Also, for the accuse person, they can show how much they regret by making depository within their capability.

• The Korean Journal of Malacology
• /
• v.31 no.1
• /
• pp.27-34
• /
• 2015

The anatomy and ultrastructure of the digestive diverticulum of Tegillarca granosa were described using light and electron microscopy. The digestive diverticulum was situated on the gonad and connected to stomach by a primary duct. Digestive diverticulum is composed of numerous digestive tubules. The epithelial layer of digestive tubule, which is simple, is composed of basophilic cells and digestive cells. Basophilic cells are columnar in shape, and the electron density is higher than that of the digestive cell. The cytoplasm has a well-developed endoplasmic reticulum, tubular mitochondria, Golgi complex and of membrane-bounded granules of high electron density. Digestive cells were classified into three types. According to cell shape, electron density and cell organelles. However, three types of epithelia was same that striated border was observed in free surface and lysosome was observed in cytoplasm. The results of this study suggest that basophilic cells and digestive cells in the digestive tubule are specialized in the extracellular and intracellular digestions, respectively.

• The Korean Journal of Malacology
• /
• v.27 no.1
• /
• pp.69-76
• /
• 2011

Gill morphology and ultrastructure of the spiny top shell, Batillus cornutus were described using light and electron microscopy (SEM and TEM). The spiny top shell, Batillus cornutus has bipectinate gill. The epithelial layer of gill filament was simple and composed of columnar epithelium, ciliated cell, mitochondria-rich cell and secretory cell. Microvilli were well-developed on the free surface of columnar epithelial cell. The epithelial cells are connected to the neighboring cells with intercelluar junctions at the apico-lateral surface. The cilia and microvilli were commonly observed on the free surface of ciliated cell. Tubular mitochondria appeared in the apical cytoplasm, and connected ciliary rootlet. Mitochondria-rich cells contained a oval-shaped nucleus in the basal area. And majority of cytoplasm was occupied by well-developed mitochondria. Result of AB-PAS (pH 2.5) and AF-AB reaction showed that secretory cells contained mainly acidic carboxylated mucosubstances. Secretory cells are unicellular glands and can be divided into four types (A, B, C and D) depending on the cell shape and ultrastructure of secretory granules.

• Polymer(Korea)
• /
• v.25 no.4
• /
• pp.451-459
• /
• 2001

Fabric ion-exchanger, aminated PP-g-styrene was synthesized with styrene monomer onto PP staple fiber by pre-irradiational grafting with E-beam and subsequent chloromethylation and amination. Degree of grafting was increased with increasing the styrene monomer concentration and the highest degree of grafting was obtained 118% at a monomer concentration of 80% styrene. Optimum condition of Mohr's salt and sulphuric acid were 1.0 ${\times}\;10^{-3}$ M and 0.1 M. Amount of amination was increased with increasing degree of grafting. Swelling ratio of aminated PP-g styrene was higher than that of trunk polymer. Ion-exchange capacity was 6.7 meq/g, which was three times greater than commercial ion-exchanger. Optimum condition of baron ion adsorption was pH 4 and amount of adsorption were increased with increasing the amount of amination.

• Polymer(Korea)
• /
• v.37 no.2
• /
• pp.177-183
• /
• 2013

Surface properties such as morphology, crystalline structure, and chemical composition of poly(vinylidene fluoride) (PVDF)/poly(methyl methacrylate) (PMMA) blend coatings prepared by dispersion coating on poly(ethylene terephthalate) (PET) film have been investigated. It was observed that the surface properties were greatly influenced by the coating temperature and blend composition according to SEM, ATR-FTIR and XPS analysis. The typical surface morphology of ${\alpha}$-crystalline structure of PVDF could be observed when the coating temperature was lower than $120^{\circ}C$ or the amount of PVDF was higher than 80 wt% in the blend. Otherwise, the crystalline structure was changed from ${\alpha}$-crystal to ${\gamma}$-crystal or amorphous state. Based on the XPS analysis, the surface segregation of PVDF chains in the blend coating was confirmed.

• Proceedings of the Safety Management and Science Conference
• /
• 2009.11a
• /
• pp.15-24
• /
• 2009

Cycling that transform human energy into mechanical energy is one of the man-machine systems out of sports fields. Benchmarking means " improving ourselves by learning from others ", therefore benchmarking toward dominant cyclist is necessary on field. the goals of this study were to provide important factors on multi-disciplines (kinematics, physiology, power, psychology) for a tailored-training program that is suitable to individual characteristics. Two cyclist participated in this study and gave consent to the experimental procedure. one was dominant cyclist (years:21 yrs, height:177 cm, mass:70 kg), and the other was non-dominant cyclist(years:21, height:176, mass:70). Kinematic data were recorded using six infrared cameras (240Hz) and QTM (software). Physiological data (VO2max, AT) were acquired according to graded exercising test with cycle ergometer and power with Wingate test used by Bar-Or et. al ( 1977) and to evaluate muscle function with Cybex. Psychological data were collected with competitive state anxiety inventory (CSAI-2) that were devised by Martens et. al (1990) and with athletes' self-management questionnaire (ASMQ) of Huh (2003). It appears that the dominant's CV(coefficient of variability) was higher than non-dominant's CV in Sports Biomechanics domain, that the dominant's values for all factors ware higher than non-dominant's values in physical, and physiological domain, and their values between cognitive anxiety and somatic anxiety were contrary to each other in psychology. Further research on multi-disciplines may lead to the development of tailored-optimal training programs applicable with key factors to enhance athletic performance by means of research including athlete, coach and parents.

• Korean Journal of Plant Resources
• /
• v.19 no.1
• /
• pp.83-87
• /
• 2006

Study on the effective cultivation method for earlier harvest of peony(Paeonia lactiflora Pall.), was carried out in Uiseong Medicinal Plant Experiment Station from 2001 to 2003. Sprouting time and flowering time in house cultivation were earlier than in field cultivation. Planting large crowns of $100{\sim}130g$ increased yield by 34%. The method that is 'Large crown($100{\sim}130g$) + dense planting + vinyl mulching for 2 years' resulted good growth and 54% yield increase. This method made it possible to harvest peony on the second year and reduce productive cost. The yield was decreased more or less in this method but yearly income was increased by 28%.

• Korean Journal of Plant Taxonomy
• /
• v.34 no.2
• /
• pp.75-85
• /
• 2004

Here we described and illustrated two new taxa of Allium (Alliaceae) from southern part of Korea. One new species, A koreanum H. J. Choi et B. U. Oh was clearly distinguished from A. splendens of sect. Reticulato-bulbosa by larger and stellately spreading pale pink perianth, apparently exsert filaments, and conical stigma as well as chromosome number. Another new variety, A. thunbergii var. teretifolium H.J. Choi et B.U. Oh was also easily distinguished from its relatives, var. thunbergii and var. deltoides by terete and hollow leaf blade. Keys to the two species of Allium sect. Reticulato-bulbosa and the three varieties of A. thunbergii (sect. Sacculiferum) in Korea were described.