• Title/Summary/Keyword: 화학 결합

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The Development Study on the Integrated Management System for Water Information based on ICT (ICT기반의 물정보 통합관리시스템 개발 연구)

  • Hong, Sok-min;Jang, Am
    • Journal of Korean Society of Environmental Engineers
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    • v.39 no.12
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    • pp.723-732
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    • 2017
  • As the development of ICT technology, in order to solve the problem of scattered water information's availability, WINS(Water management Information Networking System) by the Ministry of Land, Infrastructure and Transport was established and has been operated since 2004. However, there has been a disadvantage of providing specialized and limited information to the water resources sector mainly and a lack of active sharing of information because of no compulsory provision of information sharing between participants. In order to solve these problems, this paper carried out system development study, to do this, the status of domestic water information was surveyed and domestic and overseas related systems were compared and analyzed. The latest ICT technology was used to realize the contents as screen, and the user interface definition was created to present a role model of integrated water management through maximizing visualization by combining GIS and realtime data and providing space-time integrated information. These prior studies reached to actual construction of the ICT-based integrated management system for water information by K-water. This system is in service to the public installed in the water information portal, "MyWater".

Fabrication and loss measurement of $P_2O_5-SiO_2$ optical waveguides on Si (Si을 기판으로한 $P_2O_5-SiO_2$ 광도파로의 제작 및 손실측정)

  • 이형종;임기건;정창섭;정환재;김진승
    • Korean Journal of Optics and Photonics
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    • v.3 no.4
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    • pp.258-265
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    • 1992
  • A low loss optical waveguide of $P_{2}O_{5}-SiO_{2}$on Si substrate is produced by using the chemical vapour deposition method of $SiO_2$ thin films used in Si technology. Propagation loss of the waveguide layer was 1.65 dB/cm as produced and reduced down to 0.1 dB/cm after heat treatment at $1100^{\circ}C$. By using laser lithography and reactive ion etching method $P_{2}O_{5}-SiO_{2}$ waveguide was produced and subsequently annealed at $1100^{\circ}C$.As a result of this annealing the shape of the waveguide core was changed from rectangular to semi-circular form, and the propagation loss was reduced as down to 0.03 dB/cm at 0.6328$\mu$m and 0.04dB/cm at 1.53$\mu$m. We think that the mechanism of the reduction in propagation loss during the heat treatment is the following: 1) The hydrogen bonding in waveguide layer, which causes absorption loss, is dissociated and diffused out. 2) The roughness of the interface and the micro-structure of the waveguide layer is removed. 3) The irregularities in the cross-sectional shape of the waveguide which was induced during the lithographic process were disappeared by flowing of the waveguide core.

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Studies on the Differentiation of Chondrogenic Cells in Developing Chick Embryo I. Cellular Aggregation and Chondrogenesis (발생계배 연골세포의 분화기구에 대한 연구 I. 세포응집과 분화와의 관계)

  • 박대규;손종경;유정아;유병제;강신성
    • The Korean Journal of Zoology
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    • v.33 no.3
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    • pp.310-321
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    • 1990
  • To establish the in vitro culture system and quantitation for chondrogenesis, and to investigate the relationship between cell aggregation and chondrogenesis, chick limb bud mesenchymal cells of Hamburger-Hamilton stage 23/24 were micromass cultured in various cell densities. The chondrogenesis was assayed based on checking the alcian blue-stained nodule numbers, the amount of alcian blue extraded, the change in cell numbers, the rate of [35 S] sulfate incorporation and expression of type II collagen. Mesenchymal cells plated with an initial density of high (1 x 107 cells/ml)- and intermediates (5. $\times$ 106 cells/ml)-density were differentiated into cartilage. On the other hand, the cells of low density (2 x 106 cells/mi, 5 $\times$ 105 cells/ml) of stage 23/24 cells and the stage 18/19 cells in three kinds of cell density did not differentiate into cartilage even though the cells formed an aggregated core at the center of cultured mass. From these results and others obtained in this study, it can be stated that the stage 23/24 mesenchymal cells are likely to pass over the aggregation step and have the potentiality to differentiate into chondrocytes. Thus chondrogenesis in vitro can be observed when mesenchymal cells are plated over the threshold density of 5 $\times$ 106 cells/ml. Hyaluronidase (HAase) activity was relatively constant throughout the culture, suggesting that the role of HAase may not be important for the cells of stage 23/24.

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Effect of Extract from Fermented Black Soybean (Glycine max var. Seoritae) on the Hair Damaged by Decolorization (서리태 발효추출물이 탈색을 통해 손상된 모발에 미치는 영향)

  • Jung, Heehoon;Shin, Min Kyu;Lee, Su Yel;Lee, Sang Rin;Kim, Moo Sung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.2
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    • pp.149-155
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    • 2017
  • This study was carried out to investigate the hair protection effect of fermented black soybean extracts. The morphological characteristics, tensile strength and constitutional changes of the hair were analyzed and compared when the hair was chemically oxidized and then treated with fermented black soybean extract. As a result, treatment of oxidizing agent on virgin hair caused damage on the cuticle layer of the epidermis and decreased in tensile strength of hair from $14.32{\pm}0.83g/cm^2$ to $12.32{\pm}0.79g/cm^2$. FT-IR analysis showed the peaks at 1,077, 1,041, and $801cm^{-1}$ of the hair treated with oxidizing agent were increased compared to peak values of virgin hair, indicating that cystein in hair was decreased which is crucial to disulfide bond between keratin. On the other hand, when the damaged hair is treated with the fermented black soybean extract, cracks in the cuticle layer of the epidermis were filled, tensile strength was restored to $14.27{\pm}0.96g/cm^2$ and the ratio of oxidized cysteine in hair was decreased. These results suggest that the fermented black soybean extract is worthy of further investigation as a protective material for hair damaged by oxidizing agents.

Proposition of a Vibration Based Acceleration Sensor for the Fully Implantable Hearing Aid (완전 이식형 보청기를 위한 진동 기반의 가속도 센서 제안)

  • Shin, Dong Ho;Mun, H.J.;Seong, Ki Woong;Cho, Jin-Ho
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.11 no.2
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    • pp.133-141
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    • 2017
  • The hybrid acoustic sensor for implantable hearing aid has the structure in which a sound pressure based acoustic sensor (ECM) and a vibration based acceleration sensor are combined. This sensor combines the low frequency sensitivity of an acoustic sensor with the high frequency sensitivity of an acceleration sensor, allowing the acquisition of a wide range of sound from low to high frequency. In this paper, an acceleration sensor for use in a hybrid acoustic sensor has been proposed. The acceleration sensor captures the vibration of the tympanic membrane generated by the acoustic signal. The size of the proposed acceleration sensor was determined to diameter of 3.2 mm considering the anatomical structure of the tympanic membrane and the standard of ECM. In order to make the hybrid acoustic sensor have high sensitivity and wide bandwidth characteristics, the aim of the resonance frequency of the acceleration sensor is to be generated at about 3.5 kHz. The membrane of the acceleration sensor derives geometric structure through mathematical model and finite element analysis. Based on the analysis results, the membrane was implemented through a chemical etching process. In order to verify the frequency characteristics of the implemented membrane, vibration measurement experiment using external force was performed. The experiment results showed mechanical resonance of the membrane occurred at 3.4 kHz. Therefore, it is considered that the proposed acceleration sensor can be utilized for a hybrid acoustic sensor.

Fabrication of Anisotropic Hexagram Particles by using the Micromolding Technique and Selective Localization of Patch (미세성형 기술과 패치의 선택적 제거방법을 이용한 이방성의 육각별 입자 제조)

  • Shim, Gyurak;Yeom, Su-Jin;Jeong, Seong-Geun;Kang, Kyoung-Ku;Lee, Chang-Soo
    • Clean Technology
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    • v.24 no.2
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    • pp.105-111
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    • 2018
  • This study presents a novel and eco-friendly process that can precisely control the location of the patches on the patch particles. The method of manufacturing these anisotropic hexagram patch particles consists of sequential combinations of two separate methods such as a sequential micromolding technique for fabricating patch particles and a selective localization method for controlling the location of patches on the patch particles. The micromolding technique was carried out using physicochemically stable material as a micromold. In order to fabricate the highly stable patch anisotropic hexagram particles, the perfluoropolyether (PFPE) micromold was used to the process of the micromolding technique because they could prevent the problem of diffusion of hydrophobic monomers while conventional poly(dimethylsiloxane) (PDMS) micromold is limited to prevent the problem of diffusion of hydrophobic monomers. Based on combination methods of the micromolding technique and the selective localization method, the reproducibility and stability have been improved to fabricate 12 different types of anisotropic hexagram patch particles. This fabrication method shows the unique advantages in eco-friend condition, easy and fast fabrication due to less number of process, the feasibility of a mass production. We believe that these anisotropic hexagram patch particles can be widely utilized to the field of the directional self-assembly.

Effect on the Measurement of Trace Element by Pressure Bomb and Conventional Teflon Vial Methods in the Digestion Technique (압력용기 산분해법과 테플론 바이알에서의 산분해법이 미량원소의 함량측정에 미치는 영향)

  • Lee, Seung-Gu;Kim, Taehoon;Tanaka, Tsuyoshi;Lee, Seung Ryeol;Lee, Jong Ik
    • The Journal of the Petrological Society of Korea
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    • v.25 no.2
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    • pp.107-119
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    • 2016
  • Trace element abundances in the igneous rocks are important data for petrogenetic interpretation. Their concentrations are generally measured using ICP-MS from the dissolved solution. The acid digestion of rock powder can be performed by conventional teflon vial or pressure bomb. In this paper, we investigated a problem that happened during acid digestion experiment using conventional teflon vial or pressure bomb of BCR2 and GSP2 USGS rock standard materials. The results show that the measured concentrations of the elements like Cr, Ni, Zn, Ta, W in the BCR2 are different from the recommended values of USGS whereas those of the elements like Rb, Sr, Zr, Hf, Ta, W in the GSP2 are different from those values. Our experiment shows that defect of specific elements like Cr, Ni may happen during the sample digestion. Our results also indicate that the Cr, Ni, W, Zr, Hf, Ta concentration obtained based on an acid digestion of geological samples need to be careful in their geochemical interpretation.

Preparation of MWCNTs/Poly(methyl methacrylate) Composite Particles via the Emulsion Polymerization of Methyl Methacrylate Using MWCNTs Modified by Silanization Reaction and Their Morphological Characteristics (실란화 반응으로 표면 개질된 다중벽 탄소나노튜브(MWCNTs)와 Methyl Methacrylate의 유화중합을 통한 MWCNTs/Poly(methyl methacrylate) 복합 입자 제조 및 그 형태학적 특성)

  • Kwon, Jaebeom;Park, Seonghwan;Kim, Sunghoon;Jo, Jieun;Han, Changwoo;Ha, KiRyong
    • Polymer(Korea)
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    • v.39 no.2
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    • pp.329-337
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    • 2015
  • In this study, multi-walled carbon nanotubes (MWCNTs) were oxidized with a mixture of nitric acid and sulfuric acid. After oxidation, oxidized MWCNTs were treated with thionyl chloride ($SOCl_2$) and 1,4-butanediol (BD) in sequence at room temperature to introduce hydroxyl groups on the surface of MWCNTs. The prepared MWCNT-OH was silanized with 3-methacryloxypropyltrimethoxylsilane (MPTMS) to make MWCNT-MPTMS. The MWCNT-MPTMS was used as fillers in emulsion polymerization to make MWCNT-MPTMS/PMMA composite particles with 3 kinds of emulsifiers, hexadecyltrimethylammoniumbromide (CTAB) as a cationic, sodium dodecylbenzene sulfonate (SDBS) as an anionic and polyethylene glycol tert-octylphenyl ether (Triton X-114) as a nonionic emulsifier. Morphologies of composite emulsions were confirmed by a particle size analyzer (PSA) and a scanning electron microscope (SEM). Morphologies of emulsion polymerized MWCNT-MPTMS/PMMA with SDBS showed more uniform particle size distribution compared to those of other two emulsifiers used emulsions. MWCNT-MPTMS/PMMA showed $3.4^{\circ}C$ higher $T_g$ compared to pristine MWCNT/PMMA due to covalent bond formation at interface of MWCNT-MPTMS and PMMA.

Inflammatory Polyps in 2 Cats (두 마리 고양이에서의 염증성 용종 예)

  • Ko, Seung-Bo;Jung, Ji-Youl;Kim, Jae-Hoon;Kang, Sang-Chul;Yoon, Jeong-Sik;Yang, Jung-Hwan;Shin, Yong-Eun;Kim, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.27 no.5
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    • pp.622-625
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    • 2010
  • Inflammatory polyps in feline ear are nonneoplastic, inflammatory growths that arise from the middle ear or the eustachian tube and extended into the pharynx or external ear canal. Two 2-year-old female Russian blue cats showed 2-3 weeks history of aural discharge, crust formation in external ear, and head or ear shaking. Two masses were surgically excised from ear canal, and submitted for diagnosis. Histopathologically, these masses were covered with hyperplastic ciliated epithelium or nonkeratinizing squamous epithelium with partial erosion and ulceration. The core of masses was consisted of proliferated connective tissue and massive infiltration of mononuclear cells. Immunohistochemically, about 90% of infiltrated mononuclear cells demonstrated CD3 positive T cell. According to both polymerase chain reaction (PCR) and reverse transcriptase-PCR, tissues samples were negative for feline viral pathogens. Based on the clinical, gross, histopathologic findings, these two cases were diagnosed as inflammatory polyps originated from the middle ear in cats.

Study on Degradation Characteristic of Plastic Artwork for Conservation (플라스틱 작품 보존을 위한 열화 특성 연구)

  • Yu, Ji A;Cho, Ha Jin;Han, Ye Bin;Lee, Hyun Ju;Lee, Sang Jin;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.31 no.2
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    • pp.87-94
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    • 2015
  • Plastic artwork can be appeared crack, change of color and whitening event by various environment conditions. A large scale plastic artwork often exhibits in outside it will be directly degraded by physical and chemical degradation factor such as strong sunlight, high humidity and rainfall. We should know degradation characteristic of plastics to prevent these damages. In this study, we studied degradation characteristic of plastics (5 types of wide use plastics; polypropylene, polystyrene, polyethylene, polyvinyl chloride, polyurethane) depending on various artificial degradation conditions such as high temperature, ultraviolet and these complex conditions (high temperature and ultraviolet). As a result, polypropylene, polystyrene and polyethylene show the most visible change especially polypropylene, polystyrene. Polypropylene didn't show a great change degree of tensile strength and contact angle, on the other hand polystyrene did. Polypropylene and polystyrene weakened by photo degradation, polyvinyl chloride and polyurethane had relatively good light stability. Also the high temperature and complex conditions were most degradation characteristic. High temperature worked for degradation catalyst because its energy can not enough worked for cut off binding energy of plastics while ultraviolet condition effected as directly degradation condition. Though following results, we expect it can be applied to investigation of degradation factor depending on plastic artwork materials and basic result of plastic artworks conservation.