• Title/Summary/Keyword: Noble

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The Electrical Properties of Aluminum Bipolar Plate for PEM Fuel Cell System

  • Oh, Mee-hye;Yoon, Yeo-Seong;Park, Soo-Gil;Kim, Jae-Yong;Kim, Hyun-Hoo;Osaka, Tetsuya
    • Transactions on Electrical and Electronic Materials
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    • v.5 no.5
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    • pp.204-207
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    • 2004
  • In this work, we present the electrochemical properties of Al bipolar plate, which can be re-searched for the application of PEMFC system. Bulk resistance of the plate was measured with a four-point probe method. The electrical conductivity of noble metal coated Al plate was 4.40 x 10$^4$ S/cm. On the other hand, the electrical interfacial resistance of the noble metal coated Al plate valued at 0.15 mΩ-$\textrm{cm}^2$ and that of graphite was 0.26 mΩ-$\textrm{cm}^2$ under the holding pressure of 140 N/$\textrm{cm}^2$ at the applied current of 5 A. And the performance of Al bipolar plate for PEMFC was evaluated at various conditions. The single cell performance was more than 0.43 W/$\textrm{cm}^2$ (0.47 Wig) for noble metal coated Al bipolar plate at 5$0^{\circ}C$ under atmospheric pressure in external humidified hydrogen and oxygen condition. As the present results, we could show the results that the noble metal coated Al bipolar plates were favorable in the aspect of electrical properties compared with those of the commercialized resin-impregnated graphite plates.

Breeding of a Pink Rose Cultivar 'Noble Eye' with Few Prickles for Cut Flower (가시가 적은 분홍색 장미 '노블아이' 육성)

  • Gi, Gwang-Yeon;Hwang, In-Taek;Cho, Kyung-Chul;Yun, Bong-Ki;Choi, Kyong-Ju;Lee, Jae-Sin;Han, Tae-Ho
    • FLOWER RESEARCH JOURNAL
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    • v.18 no.4
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    • pp.299-302
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    • 2010
  • A new standard pink rose cultivar 'Noble Eye' was bred from the cross between pink standard cultivar 'Noblesse' and pink standard cultivar 'Pretty Woman' at the Jeollanamdo Agricultural Research and Extension Services (JARES). The cross was made in 2003 and, 'Noble Eye' was finally selected in 2009 after investigating characteristics for three times from 2006 to 2009. 'Noble Eye' a pink standard cultivar has good flower shape with few prickles. The major characteristics of this cultivar was $125.7stems/m^2/year$ in yield. 69.8 cm in length of cut flower, 6.6 cm in flower diameter, 40.5 in petal number, and 9.4 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar was relatively higher than that of control cultivar, 'Noblesse'.

Conversion of Cellulose into Polyols over Noble Metal Catalysts Supported on Activated Carbon (활성탄에 담지된 귀금속 촉매를 이용한 셀룰로우스의 폴리올로의 전환)

  • You, Su-Jin;Kim, Saet-Byul;Kim, Yong-Tae;Park, Eun-Duck
    • Clean Technology
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    • v.16 no.1
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    • pp.19-25
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    • 2010
  • In this work, the conversion of crystalline cellulose into polyols in the presence of hydrogen was examined over noble metal (Pt, Ru, Ir, Rh, and Pd) catalysts supported on activated carbon. For comparison, Pt/${\gamma}-Al_2O_3$ and Pt/H-mordenite were also investigated. Several techniques: $N_2$ physisorption, X-ray diffraction(XRD), inductively-coupled plasma-atomic emission spectroscopy (ICP-AES), temperature-programmed reduction with $H_2$ ($H_2$-TPR) and CO chemisorption were employed to characterize the catalysts. The cellulose conversion was not strongly dependent on the types of the catalyst used. Pt/AC showed the highest yields to polyols among activated carbon-supported noble metal catalysts, viz. Pt/AC, Ru/AC, Ir/AC, Rh/AC and Pd/AC.

Development and Evaluation of Bipolar Plates Coated with Noble Metals for Polymer Electrolyte Membrane Fuel Cells (Noble Metal이 코팅된 금속분리판 개발 및 성능 평가)

  • Seo, Hakyu;Han, In-Su;Jung, Jeehoon;Kim, Minsung;Shin, Hyungil;Hur, Taeuk;Cho, Sungbaek
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.90.2-90.2
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    • 2010
  • The coated metallic bipolar plates are getting attractive due to their good feasibility of mass production, low contact resistance, high electrical/thermal conductivity, low gas permeability and good mechanical strength comparing with graphite materials. Yet, metallic bipolar plates for polymer electrolyte membrane(PEM) fuel cells typically require coatings for corrosion protection. Other requirements for the corrosion protective coatings include low electrical contact resistance between metallic bipolar plate and gas diffusion layer, good mechanical robustness, low mechanical and fabrication cost. The authors have evaluated a number of protective coatings deposited on stainless steel substrate by electroplating. The coated metallic bipolar plates are investigated with an electrochemical polarization tests, salt dipping tests, adhesion tests for corrosion resistance and then the contact resistance was measured. The results showed that the selective samples electroplated with optimized method, satisfied the DOE target for corrosion resistance and contact resistance, and also were very stabilized in the typical fuel cell environments in the long-term.

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Synthesis and Applications of Noble Metal and Metal Silicide and Germanide 1-Dimensional Nanostructures

  • Yoon, Ha-Na;Yoo, Young-Dong;Seo, Kwan-Yong;In, June-Ho;Kim, Bong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2830-2844
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    • 2012
  • This review covers recent developments in our group regarding the synthesis, characterization and applications of single-crystalline one-dimensional nanostructures based on a wide range of material systems including noble metals, metal silicides and metal germanides. For the single-crystalline one-dimensional nanostructures growth, we have employed chemical vapor transport approach without using any catalysts, capping reagents, and templates because of its simplicity and wide applicability. Au, Pd, and Pt nanowires are epitaxially grown on various substrates, in which the nanowires grow from seed crystals by the correlations of the geometry and orientation of seed crystals with those of as-grown nanowires. We also present the synthesis of numerous metal silicide and germanide 1D nanostructures. By simply varying reaction conditions, furthermore, nanowires of metastable phase, such as $Fe_5Si_3$ and $Co_3Si$, and composition tuned cobalt silicides (CoSi, $Co_2Si$, $Co_3Si$) and iron germanides ($Fe_{1.3}Ge$ and $Fe_3Ge$) nanowires are synthesized. Such developments can be utilized as advanced platforms or building blocks for a wide range of applications such as plasmonics, sensings, nanoelectronics, and spintronics.

Emission Properties of Electrodeless Sulfur Lamp by Additives (화합물 첨가에 따른 무전극 황램프의 발광특성)

  • Lee, Jong-Chan;Kim, Kwang-Soo;Park, Dae-Hee;Hwang, Myung-Keun;Park, Cheol-Soon
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1890-1892
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    • 2002
  • The technology of sulfur lamps that has physical and electrical characteristics comparable to current HID source has been reported. The fundamental principles of the operation of microwave discharges that are used to convert microwave energy to broad spectrum visual light are known. In this paper, emission dependance of microwave discharges in mixture content of sulfur with noble gases was studied. It is shown that the excitation of this gaseous mixture is carried out in two phases: (l) ionization of noble gas atoms by a microwave field and (2) the consequent maintenance of slightly ionized nonequilibrium plasma by the field. These two processes have essentially various thresholds for the microwave pump. The purpose of this work is to investigate spectral properties of the high frequency discharges in a mixture sulfur vapors with noble gases.

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A Study on the Recipe of Byung-Kwa-Ryu (Korean rice cake and cookie) in the Old Cookbooks of Jong-Ga (Head & Noble Family) (종가(宗家)의 고조리서를 통해본 병과류 연구)

  • Kwon, Yong-Seok;Kim, Young;Choe, Jeong-Sook;Lee, Jin-Young
    • Journal of the Korean Society of Food Culture
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    • v.29 no.1
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    • pp.61-83
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    • 2014
  • The aim of this study was to review Byung-Kwa-Ryu recipes in old cookbooks of the head & noble family (Jong-Ga). As for details and classification, we examined the materials and recipes of Byung-Kwa-Ryu. To accomplish this, old cookbooks of the head & noble family ("Soowoonjabbang", "Eumsikdimibang", "Onjubub", and "Jusiksiui") were reviewed. The introduced Byung-Kwa-Ryu recipes numbered 47 total; four from "Soowoonjabbang", 18 from "Eumsikdimibang", nine from "Onjubub", and 16 from "Jusiksiui". We classified the foods (Byung-Kwa_Ryu) into two categories, Tteok-Ryu (Korean rice cake) and Kwa-Jung-Ryu (Korean traditional cookie), on the basis of previous studies. These were further classified into 11 categories: Tteok-Ryu (Jjin-tteok, Salmeun-tteok, Chin-tteok, Jijin-tteok), Kwa-Jung-Ryu (Yumilkwa, Yukwa, Jeongkwa, Dasik, Kwapyun, Dang (Yeot), and others. The most common Byung-Kwa-Ryu type was Jjin-tteok in Tteok-Ryu (14). The next most common Byung-Kwa-Ryu types were Yukwa in Kwa-Jung-Ryu (6) and Yumilkwa in Kwa-Jung-Ryu (5).

Isolation and Identification of Noble Lactic Acid Bacteria

  • Yeo, Han-Cheol;Jang, Jin-Young;Park, Hyeong-Jun;Min, Byung-Tae;Yoo, Min
    • Quantitative Bio-Science
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    • v.37 no.2
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    • pp.125-132
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    • 2018
  • In this study, noble strains of lactic acid bacteria were isolated and identified by genetic analysis of 16s rRNA. Also, pH-dependent growth curve, cholesterol assimilation ability and sugar production efficiency were measured. Lactic acid bacteria were identified to inhabit in the milks from various animals. Results of sequence analysis showed that there were differences in 16S rRNA sequence among strains and part of gene deletion was also recognized. Growth rates were varied, too, depending on the pH of the medium. Lactobacillus rhamnosus LOCK908 isolated from cow milk showed the highest growth rate and high cholesterol assimilation ability. Results of sugar fermentation tests were relatively consistent with the sequencing results. So, we propose newly isolated Lactobacillus rhamnosus LOCK908 as useful candidate for a starter of fermented beverage and probiotics. Results of this study will contribute to the isolation and identification of noble Lactic acid bacteria and to the public health.

Optimal Strategy of Hybrid Marketing Channel in Electronic Commerce (전자상거래하에서의 하이브리드 마케팅 채널의 믹스 전략에 관한 연구)

  • Chun, Se-Hak;Kim, Jae-Cheol
    • Asia pacific journal of information systems
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    • v.17 no.2
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    • pp.83-95
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    • 2007
  • We are motivated by how offline and online firms compete. The Internet made many conventional offline firms build a dynamic online business as another sales channel using their advantages such as brand equity, an existing customer base with comprehensive purchasing data, integrated marketing, economies of scale, and longtime experience with the logistics of order fulfillment and customer service. Even though the hybrid selling using both offline and online channel seems to have advantages over a pure online retailer, all the conventional offline firms are not seen to create an online business. Many conventional offline firms began to launch online business since the Internet era, however, just being online business is not likely to guarantee success. According to Bizate.com's report whether the hybrid channel strategy is successful is still under investigation. For example, consider the classic case of Barnes and Noble versus Amazon.com, Barnes and Noble was already the largest chain of bookstores in the U,S., when Amazon.com was established in 1995, BarnesandNoble.com followed suit in 1997, After suffering losses in its initial years, Amazon finally turned profitable in 2003. In 2004, Amazon's net income was $588 million on revenues of $6.92 billion, while Barnes and Noble earned $143 million on revenues of $4.87 billion, which included BarnesandNoble.com's loss of $21 million on revenues of $420 million. While these examples serve to motivate our thinking, it does not explain when offline firms should venture online. It also does not provide an analytical framework that can generalized to other competitive online-offline situations. We attempt to do this in this paper and analyze a hybrid channel model where a conventional offline firm competes against online firms using its own direct online channels. We are particularly interested in an optimal channel strategy when a conventional offline firm sells its products through its own direct online channel to compete with other rival online firms. We consider two situations where its direct online channel and other online firms are symmetric and asymmetric in the brand effect. The analysis of this paper presents several findings. In the symmetric model where a hybrid firm's online channel is not differentiated from a pure online firm, (i) a conventional offline firm will not launch its online business. In the asymmetric model where a hybrid firm's online channel is differentiated from a pure online firm, (ii) a conventional offline firm can launch its online business if its brand effect is greater than a certain threshold. (iii) there is a positive relationship between its brand effect and online customer costs showing that a conventional offline firm needs more brand effect in order to launch online business as online customer costs decrease. (iv) there is a negative relationship between its brand effect and the number of customers with access to the Internet showing that a conventional offline firm tends to launch its online business when customers with access to the Internet increases.

Effect of various casting alloys and abutment composition on the marginal accuracy of bar-type retainer (합금의 종류와 지대주 성분이 바형 유지 장치의 변연 적합도에 미치는 영향)

  • Lee, Yun-Hui;Song, Young-Gyun;Lee, Joon-Seok
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.2
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    • pp.85-91
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    • 2012
  • Purpose: The object of this study was to determine if the low-priced alloy and metal UCLA abutment could be available for manufacturing bar-retained framework of implant prosthesis. Materials and methods: Bar structure was classified into 4 groups, The specimen of group 1 and 2 were based on casting high noble metal alloys and noble metal alloys with gold UCLA abutment. The specimen of group 3 and 4 were based on casting noble metal alloys and base metal alloys with metal UCLA abutment. Cast bar structure was installed in an acrylic resin model and only the screw on the hexed abutment side was tightened to 20 Ncm. On the opposite side, vertical discrepancy was measured with stereo microscope from front, back, and lateral side of the implant-abutment interface. One-way ANOVA was performed to analyze the marginal fit discrepancy. Results: One-way ANOVA test showed significant differences among all groups ($P$<.05) except for Group 1 and 3. Among them, difference between Group 1 and 2 was noticeable. Measured vertical discrepancies were all below $70{\mu}m$ except to Group 2. Conclusion: Base metal alloy and metal UCLA abutment could be used as an alternative to high-priced gold alloy for implant bar-retained framework.