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An Efficient and Convenient Esterification of Carboxylic Acids Using 4,5-Dichloro-2-[(4-nitrophenyl)sulfonyl]pyridazin-3(2H)-one

  • Kim, Jeum-Jong;Park, Yong-Dae;Kweon, Deok-Heon;Kang, Young-Jin;Kim, Ho-Kyun;Lee, Sang-Gyeong;Cho, Su-Dong;Lee, Woo-Song;Yoon, Yong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.25 no.4
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    • pp.501-505
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    • 2004
  • Esterification of aliphatic or aromatic carboxylic acids with alcohols using 2-(4-nitrobenzenesulfonyl)-4,5-dichloropyridazin-3(2H)-one (3) in the presence of base in organic solvents gave the corresponding esters in excellent yields

Three-Dimensional Self-Assembly of Gold Nanoparticles Using a Virus Scaffold

  • Kang, Aeyeon;Lee, Young-Mi;Kang, Hyo Jin;Chung, Sang Jeon;Yun, Wan Soo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.651-651
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    • 2013
  • Templated strategy is a very powerful tool for creating multi-dimensional self assembly of nanomaterials. Since viral protein cages have a uniform size with a well-defined structure, they can serve as an excellent template for the formation of a three-dimensional self-assembly of synthetic nanoparticles. In this study, we have examined the feasibility of the 3D self-assembly of gold nanoparticles of various sizes using a brome mosaic virus (BMV) capsid with cysteine groups expressed on its surface as a scaffold for the assembly. It was found that the three-dimensional clusters of gold nanoparticles with a designed structure were attainable by this approach, which was verified by transmission electron microscope (TEM) and dynamic light scattering (DLS) analysis.

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Glass Fiber Composite Material with Polyurethane Toughener in Unsaturated Polyester Resin (UPR) (불포화 폴리에스터 (UPR)에 폴리우레탄을 첨가하여 강인성을 부여한 유리섬유 복합소재)

  • Baek, Chang Wan;Jang, Tae Woo;Kim, Taehee;Kim, Hye Jin;Kim, Hyeon-Gook;Kim, Changyoon;Seo, Bongkuk;Lim, Choong-Sun
    • Journal of Adhesion and Interface
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    • v.22 no.2
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    • pp.63-68
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    • 2021
  • Unsaturated Polyester Resin (UPR) is in general used as a resin to prepare for composite materials with reinforcing materials such as glass fibers. UPR, a thermosetting resin, is used in industry to prepare for sheet molding compound (SMC) molding prepreg that has excellent productivity and is advantageous for mass production among various molding methods of composite materials. The fiber-reinforced composite material using UPR as a matrix material is light and has the advantage of excellent physical properties, but it is weak against impact and is fragile. Four types of polyurethane were synthesized and added to UPR resin to overcome the shortcomings.

Genotype and Phenotype of Echinococcus granulosus Derived from Wild Sheep (Ovis orientalis) in Iran

  • Eslami, Ali;Meshgi, Behnam;Jalousian, Fatemeh;Rahmani, Shima;Salari, Mohammad Ali
    • Parasites, Hosts and Diseases
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    • v.54 no.1
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    • pp.55-60
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    • 2016
  • The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain.

Machining Evaluation of Carbide Drill and Cermet Reamer Using Polishing Media Based on Drag Finishing Process (드래그 피니싱 공정 기반 폴리싱 연마제를 이용한 초경 드릴 및 서멧 리머 공구의 가공 평가)

  • Ha, Jeong-Ho;Sa, Min-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.2
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    • pp.23-30
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    • 2022
  • After drilling, reaming is required to process a workpiece for obtaining an excellent surface quality. In general, a cermet is defined as a "composite of a ceramic hard phase and metal-bonded phase." Cermets have excellent abrasion resistance, thermal resistance, and performance in finishing operations that require surface roughness and processing precision. However, although cermets have significant advantages, research on them is insufficient. In this study, workpiece SM45C was machined using drills and cermet reamers. The cermet reamer was processed for drag finishing for 0, 4, and 6 min. The experimental results showed the effects of drag finishing on surface roughness and dimensional accuracy.

Viewing Angle Switching using Hybrid Aligned Nematic Liquid Crystal Display Driven by a Fringe-Field

  • Chin, Mi-Hyung;Jeong, Eun;Lim, Young-Jin;Kim, Jin-Ho;Srivastava, Anoop Kumar;Lee, Seung-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1386-1389
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    • 2008
  • Conventional viewing angle switching electrode requires pixel division and additional liquid crystal panel. Hence the conventional viewing angle switching has low aperture ratio and high thickness. In this paper we proposed new viewing angle switching using hybrid aligned nematic mode by fringe-field electrode field (named HAN-FFS) with single liquid crystal panel. The fringe-field switching electrode is located at the bottom, and the additional common electrode is located at the top of the cell to control viewing angle. The proposed device is free from additional liquid crystal panel and pixel division. Consequently, the suggested structure has not only high aperture ratio but also show an excellent potential for viewing angle switching.

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Development of “Hanaomoi”: An Original Variety of Aomori Rice Suitable for Japanese Sake Production

  • Ichita, Junji;Saito, Tomoaki;Ishida, Kazunori;Iwama, Naoko;Muranaka, Yasuhito;Mikami, Taisei
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.46-50
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    • 2003
  • In order to develop a new variety of rice that adapts to the climate of Aomori prefecture and possesses characteristics suitable for production of high quality Japanese sake, artificial cross experiments were executed between Yamadanishiki, which is widely used nationwide as an authentic variety of rice for sake production, and Hanafubuki, which was peviously developed by Aomori prefecture. An excellent hybrid, named Hanaomoi, was selected and fixed by a series of selection experiments and systematic cultivation. Unpolished Hanaomoi rice contained less amount of protein than Yamadanishiki and Hanafubuki. Unpolished rice of Hanaomoi was harder than Yamadanishiri and Hanafubuki, therefore polishing treatment was done in high yield and one could obtain a high degree of polish on the rice(namely 40% polishing). These features are advantageous to production of high quality of sake.Test brewing using 40% polished Hanaomoi gave rise to a characteristic sake that contained a slightly higher amount of alcohol and flavor components than Yamadanishiki and Hanafubuki. Sensory tests concluded that sake from Hanaomoi was as superior as the one from authentic Yamadanishiki. Hanaomoi is a promising variety of rice suitable for production of a high quality sake exclusive to Aomori prefecture.

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Indirect Measurement of the Amounts of Casein Phosphopeptides Added to Dangmyon (Starch Vermicelli or Glass Noodle) as a Calcium-Absorption Enhancer

  • Choi, Jong-Woo;Kim, Sung-Heung;Kyung, Jung-Soo;Yoon, Ho-Seok;Kim, Jae-Yoo;Yoo, Ik-Je;Ham, Young-Jae;Kim, Seong-Tae;Park, Ki-Moon
    • Journal of Dairy Science and Biotechnology
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    • v.40 no.4
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    • pp.173-181
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    • 2022
  • Industrial-scale Ca-fortified Dangmyon was manufactured with added casein phosphopeptides (CPP) to increase Ca adsorption in the intestine. Very low P content in eggshell Ca (egg Ca) and Dangmyon could make it possible to indirectly measure CPP content in Dangmyon. Partitions of the whole P present in Dangmyon were made into sweet potato, egg Ca, and CPP. The CPP content was obtained by multiplying CPP per P by the amount of P partitioned into CPP. It was found that 88.46% of CPP was obtained. However, when milk Ca, which was much higher in P, was added to fortify Dangmyon with CPP, it was found that the CPP content was either under- or over-estimated. Care must be taken when a much higher content of P as a Ca source is selected using this method. It was discovered that the added Ca and CPP were retained after cooking at boiling temperature; therefore, Dangmyon could be an excellent Ca and CPP carrier for humans.

Initial Ignition Time and Calorific Value Enhancement of Briquette with Added Pine Resin

  • Gustan PARI;Lisna EFIYANTI;Saptadi DARMAWAN;Nur Adi SAPUTRA;Djeni HENDRA;Joseph ADAM;Alfred INKRIWANG;Rachman EFFENDI
    • Journal of the Korean Wood Science and Technology
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    • v.51 no.3
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    • pp.207-221
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    • 2023
  • The increasing demand for clean energy requires considerable effort to find alternative energy sources, such as briquettes. This research aims to develop a charcoal briquette with added pine resin (API) that has excellent combustion speed and distinctive aroma. Briquettes are composed of charcoal, pine resin (concentration: 0%-30%), and starch (up to 7%). They are produced in several stages, including coconut shell pyrolysis in conventional combustion, to obtain charcoal for the briquette precursor. Briquette compaction is conducted by mixing and densifying the charcoal, pine resin, and starch using a hydraulic press for 3 min. The hydraulic press has a total surface area and diameter of 57.7 cm2 and 3.5 cm, respectively. The briquettes are dried at different temperatures, reaching 70℃ for 24 h. The study results show that the briquettes have a thickness and diameter of up to 2 and 3.5 cm, respectively; moisture of 2.18%-2.62%; ash of 11.61%-13.98%; volatile matter of 27.15%-51.74%; and fixed carbon content of 40.24%-59.46%. The compressive strength of the briquettes is 186-540 kg/cm2. Their calorific value is 5,338-6,120 kcal/kg, combusting at a high speed of 0.15-0.40 s. The methoxy naphthalene, phenol, benzopyrrole, and lauryl alcohol; ocimene, valencene, and cembrene are found in the API. The API briquette has several chemical compounds, such as musk ambrette, ocimene, sabinene, limonene, 1-(p-cumenyl) adamantane, butane, and propanal, which improve aroma, drug application, and fuel production. Accordingly, API briquettes have considerable potential as an alternative energy source and a health improvement product.

Highly Manufacturable 65nm McFET (Multi-channel Field Effect Transistor) SRAM Cell with Extremely High Performance

  • Kim, Sung-Min;Yoon, Eun-Jung;Kim, Min-Sang;Li, Ming;Oh, Chang-Woo;Lee, Sung-Young;Yeo, Kyoung-Hwan;Kim, Sung-Hwan;Choe, Dong-Uk;Suk, Sung-Dae;Kim, Dong-Won;Park, Dong-Gun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.6 no.1
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    • pp.22-29
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    • 2006
  • We demonstrate highly manufacturable Multi-channel Field Effect Transistor (McFET) on bulk Si wafer. McFET shows excellent transistor characteristics, such as $5{\sim}6 times higher drive current than planar MOSFET, ideal subthreshold swing, low drain induced barrier lowering (DIBL) without pocket implantation and negligible body bias dependency, maintaining the same source/drain resistance as that of a planar transistor due to the unique feature of McFET. And suitable threshold voltage ($V_T$) for SRAM operation and high static noise margin (SNM) are achieved by using TiN metal gate electrode.