• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.478-478
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• 2012

Recently, there are many researches in order to increase the deposition rate (D/R) and improve film uniformity and quality in the deposition of microcrystalline silicon thin film. These two factors are the most important issues in the fabrication of the thin film solar cell, and for the purpose of that, several process conditions, including the large area electrode (more than 1.1 X 1.3 (m2)), higher pressure (1 ~ 10 (Torr)), and very high frequency regime (VHF, 40 ~ 100 (MHz)), have been needed. But, in the case of large-area capacitively coupled discharges (CCP) driven at frequencies higher than the usual RF (13.56 (MHz)) frequency, the standing wave and skin effects should be the critical problems for obtaining the good plasma uniformity, and the ion damage on the thin film layer due to the high voltage between the substrate and the bulk plasma might cause the defects which degrade the film quality. In this study, we will propose the new concept of the large-area multi-electrode (a new multi-electrode concept for the large-area plasma source), which consists of a series of electrodes and grounds arranged by turns. The experimental results with this new electrode showed the processing performances of high D/R (1 ~ 2 (nm/sec)), controllable crystallinity (~70% and controllable), and good uniformity (less than 10%) at the conditions of the relatively high frequency of 40 MHz in the large-area electrode of 280 X 540 mm2. And, we also observed the SEM images of the deposited thin film at the conditions of peeling, normal microcrystalline, and powder formation, and discussed the mechanisms of the crystal formation and voids generation in the film in order to try the enhancement of the film quality compared to the cases of normal VHF capacitive discharges. Also, we will discuss the relation between the processing parameters (including gap length between electrode and substrate, operating pressure) and the processing results (D/R and crystallinity) with the process condition map for ${\mu}c$-Si:H formation at a fixed input power and gas flow rate. Finally, we will discuss the potential of the multi-electrode of the 3.5G-class large-area plasma processing (650 X 550 (mm2) to the possibility of the expansion of the new electrode concept to 8G class large-area plasma processing and the additional issues in order to improve the process efficiency.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.81-85
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• 2003

To verify importance of the intervening sequence between the ribosome binding site (RBS) and the initiation codon for expression of Bacillus thuringiensis $\delta$-endotoxin, the pProMu, containing SphI and NcoIsites between RBS and the initiation codon of the cry1Ac gene, and the deletion derivatives of pProMu were constructed and transformed into the B. thuringiensis subsp. kurstaki $Cry^{-B}$ strain. The pProMu-ΔSphIhad identical six bases of intervening sequence to pProAc though the arrangement of sequence was different. Other mutants containing pProMu had 1 or 10 or 14 bases between RBS and the initiation codon. Among deletion mutants, only ProMu-ΔSphI/CB only produced 130 kDa typical bipyramidal crystals like those seen for ProAc/CB. However, ProMu/CB, $ProMu-{\Delta}NcoI$, and ProMu-ΔSphI＋NcoIdid not produce Cry1Ac crystals. In conclusion, the results suggest that 6-base intervening sequence was important for expression of cry1-type class gene. Furthermore, spacing effect of the intervening sequences may play an important role in expression of individual crystal proteins in B. thuringiensis without doubt.

• Journal of the Korean Society of Costume
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• v.59 no.3
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• pp.96-108
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• 2009

This study is made on the royal lady's dress In late Joseon dynasty according to the King Heon-jong and Lady Kyung-bin's Wedding Diary in the year of Jung-mi(1847) and summarised as follows: Girls' full dress was a set of a red skirt, a violet undo. jacket, and a light yellow jacket and a green Gyeon-ma-gi(a kind of top jacket) with he. hair Saeng-meo-ri hanging Do-tu-rak-daeng-gi(a kind of hair ribbon). At the big ceremony, girls wore a green Dang-ui instead of Gyeon-ma-gi. A girl picked up as a royal concubine wore a green Won-sam, which was decorated with gilt letters meaning longevity, patched emblems of gilt letter meaning longevity on the breast and on the back, belted with Bong-dae(a red sash with gilt phoenexes), like a princess's full dress. At the Kyung-bin's installation of Crown Princess and her first greeting ceremony with royal elders, she wore a green Won-sam as a formal dress, which had an embroidered emblem of phoenix, the belt with crystal ornaments, Pae-ok(佩玉), Kyu(圭) of blue jade, Shou(綬) with an phoenix. At a Dong-wrae-yun(drinking ceremony after bride and bridegroom's bowing to each other), she wore the embroidered red Jang-sam as a formal dress. Kyung-bin wore a purple Won-sam with Bong-dae as a full dress for a royal feast. According to the occasions, the same dress was differentiated with ornaments and rotors. Ji-keum-bal was an attire for ordinary ceremony. The attire was equipped with a woven gold green Dang-ui with an emblem of phoenix, a blue gilt underskirt and a red gilt overskirt. No-ui was worn as outdoor clothes. Jang-sam was worn by various classes, so it was differentiated with materials and names according to her class.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.5
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• pp.383-390
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• 2001

We have investigated the L $i_{1+x}$M $n_2$ $O_4$system as a cathode material for lithium rechargeable batteries. To improve the cycle performance of spinel LiM $n_2$ $O_4$ as the cathode of 4V class lithium secondary batteries, spinel phase L $i_{1+x}$M $n_2$ $O_4$(x=0, 0.025, 0.05, 0.075) was prepared at 75$0^{\circ}C$ for 48h. The preparation of L $i_{1+x}$M $n_2$ $O_4$ from L $i_2$ $O_3$ and Mn $O_2$ under air is studied. The compounds were synthesized by using solid-state reaction. Structural refinements were carried out with a Rietveld-refinement program. Electrochemical properties were examined using the Li/L $i_{1+x}$M $n_2$ $O_4$ cells. The capacity of L $i_{1+x}$M $n_2$ $O_4$ decreases with increases lithium content, while the cycle life improves. The initial discharge capacity are 118mAh/g and 116mAh/g for LiM $n_2$ $O_4$ decreases with increases lithium content, while the cycle life improves. The initial discharge capacity are 118mAh/g and 116mAh/g for LiM $n_2$ $O_4$ and L $i_{1.025}$M $n_2$ $O_4$, respectively.pectively.

• Korean Journal of Materials Research
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• v.22 no.8
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• pp.409-415
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• 2012

$TiO_2$ thin films for high energy density capacitors were prepared by r.f. magnetron sputtering at room temperature. Flexible PET (Polyethylene terephtalate) substrate was used to maintain the structure of the commercial film capacitors. The effects of deposition pressure on the crystallization and electrical properties of $TiO_2$ films were investigated. The crystal structure of $TiO_2$ films deposited on PET substrate at room temperature was unrelated to deposition pressure and showed an amorphous structure unlike that of films on Si substrate. The grain size and surface roughness of films decreased with increasing deposition pressure due to the difference of mean free path. X-ray photoelectron spectroscopy (XPS) analysis revealed the formation of chemically stable $TiO_2$ films. The dielectric constant of $TiO_2$ films was significantly changed with deposition pressure. $TiO_2$ films deposited at low pressure showed high dissipation factor due to the surface microstructure. The dielectric constant and dissipation factor of films deposited at 70 mTorr were found to be 100~120 and 0.83 at 1 kHz, respectively. The temperature dependence of the capacitance of $TiO_2$ films showed the properties of class I ceramic capacitors. $TiO_2$ films deposited at 10~30 mTorr showed dielectric breakdown at applied voltage of 7 V. However, the films of 500~300 nm thickness deposited at 50 and 70 mTorr showed a leakage current of ${\sim}10^{-8}{\sim}10^{-9}$ A at 100 V.

• Journal of Integrative Natural Science
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• v.3 no.2
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• pp.72-77
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• 2010

Alginate lyases, also known as alginases or alginate depolymerases, catalyze the degradation of alginate by a ${\beta}$-elimination mechanism that has yet to be fully elucidated. Alginate is a copolymer of ${\alpha}$-L-guluronate (G) and its C5 epimer ${\beta}$-D-mannuronate (M), arranged as homopolymeric G blocks, M blocks, alternating GM or random heteropolymeric G/M stretches. Almost all alginate lyases depolymerize alginate in an endolytical fashion via a ${\beta}$-elimination reaction. The alginate lyase Atu3025 from Agrobacterium tumefaciens strain C58, consisting of 776 amino-acid residues, is a novel exotype alginate lyase classified into polysaccharide lyase family 15. Till now there is no crystal structure available for this class of proteins. Since there is no template with high sequence identity, three-dimensional coordinates for exotype alginate lyase (PL 15 family) were determined using modeling methods (Comparitive modeling and Fold recognition). The structures were modeled using the X-ray coordinates from Heparinase protein family (PDB code: 3E7J). This enzyme (Atu3025) displays enzymatic activity for both poly-M and poly-G alginate. Since poly-M is widespread; docking of a tri-mannuronate against the modeled structure was performed. We identified some of those residues which are crucial for lyase activity. The results from this study should guide future mutagenesis studies and also provides a starting point for further proceedings.

• Journal of Ginseng Research
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• v.44 no.1
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• pp.14-23
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• 2020

Ginseng has been used as a popular herbal medicine in East Asia for at least two millennia. However, 20(R)-ginseng saponins, one class of important rare ginsenosides, are rare in natural products. 20(R)-ginseng saponins are generally prepared by chemical epimerization and microbial transformation from 20(S)-isomers. The C20 configuration of 20(R)-ginseng saponins are usually determined by ¹³C NMR and X-ray single-crystal diffraction. 20(R)-ginseng saponins have antitumor, antioxidative, antifatigue, neuroprotective, and osteoclastogenesis inhibitory effects, among others. Owing to the chemical structure and pharmacological and stereoselective properties, 20(R)-ginseng saponins have attracted a great deal of attention in recent years. In this study, the discovery, identification, chemical epimerization, microbial transformation, pharmacological activities, and metabolism of 20(R)-ginseng saponins are summarized.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.3
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• pp.1-17
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• 2007

This study is a review of Ipsik, the decorative ornaments found on traditional Korean horsehair hats, known as Ipja, which were worn by men in the late Joseon Dynasty. In a broad sense, Ipsik are regarded as men's accessories. Therefore, although this study is limited to Ipja, it is significant in the sense that it delves into one facet of men's accessories in detail. Because the appearance of the horsehair hats was rather mundane, Ipsik and Ibyeong were added as ornaments. During the Joseon period, various types of hat ornaments existed, named Maeksu, Hosu, Gongjagu, Sangmo, Jingdori, Ijeon, Guyeongja and Ibyeong. A person's social ranking and class could be discerned by the materials used in the Ipsik he wore. Jeongja, a decorative accessory used to attach to an official's hat, was institutionalized in the sixteenth year of King Gongmin's reign(1367), during the Goryeo Dynasty, prior to the founding of China's Ming Dynasty in 1368, which indicates that Jeongja were influenced by the Yuan Dynasty. A record in Lao Chi'ta (a textbook of spoken Chinese estimated circa 1346) confirms this fact. Based on a review of literature, we learn that just as with Ongno, Jeongja were imported for use on Jeonrip, a soldier's hat. During the Ching Dynasty, Jeongja were further subdivided and more exquisitely designed. On the other hand, in the Joseon Dynasty, a rule was handed down mandating that a royal prince use gold for his jeongja, officials at third rank or above use silver, and governors, commanders in chief, and officials with the Office of Inspector General and Office of Censor General use jade. Inspectors were permitted to use crystal. Jeongja made of jade were used until the late Joseon Dynasty.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.237-241
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• 2000

The structural, electrical and etching characteristics of Al alloy thin film with low impurity concentrations AlNd deposited by using do magnetron sputtering deposition are investigated for the applications as gate bus line in the TFt-LCD panel. And ITO thin film was deposited on AlNd, then the contact resistance was measured by Kelvin resistor. The deposited thin films show the decrease of resistivity and the increase of grain size after the RTA at $300^{\circ}C$ for 20 min. Moreover, the resistivity of AlNd does not show appreciable grain size dependence after RTA. It is concluded that the decrease of resistivity after RTA is due to the increase of grain size. The annealed AlNd is found to be hillock free. The etching profiles of AlNd was good and the minimun contact resistance was about $110\;{\mu\Omega}cm$. Calculation results reveal that the AlNd (2wt.%) thin film can be applicable to 25" SXGA class TFT-LCD panels.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.75.2-75.2
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• 2013

Atomic layer deposition (ALD), utilizing self-limiting surface reactions, could offer promising perspectives for future efficient energy conversion devices. The capabilities of ALD for surface/interface modification and construction of novel architectures with sub-nanometer precision and exceptional conformality over high aspect ratio make it more valuable than any other deposition methods in nanoscale science and technology. In the context, a variety of researches on fabrication of active materials for energy conversion applications by ALD are emerging. Among those materials, one-dimensional nanotubular titanium dioxide, providing not only high specific surface area but also efficient carrier transport pathway, is a class of the most intensively explored materials for energy conversion systems, such as photovoltaic cells and photo/electrochemical devices. The monodisperse, stoichiometric, anatase, TiO2 nanotubes with smooth surface morphology and controlled wall thickness were fabricated via low-temperature template-directed ALD followed by subsequent annealing. The ALD-grown, anatase, TiO2 nanotubes in alumina template show unusual crystal growth behavior which allows to form remarkably large grains along axial direction over certain wall thickness. We also fabricated dye-sensitized solar cells (DSCs) introducing our anatase TiO2 nanotubes as photoanodes, and studied the effect of blocking layer, TiO2 thin films formed by ALD, on overall device efficiency. The photon convertsion efficiency ~7% were measured for our TiO2 nanotubebased DSCs with blocking layers, which is ~1% higher than ones without blocking layer. We also performed open circuit voltage decay measurement to estimate recombination rate in our cells, which is 3 times longer than conventional nanoparticulate photoanodes. The high efficiency of our ALD-grown, anatase, TiO2 nanotube-based DSCs may be attributed to both enhanced charge transport property of our TiO2 nanotubes photoanode and the suppression of recombination at the interface between transparent conducting electrode and iodine electrolytes by blocking layer.