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Phase Cooperation Between Mo-V-O and Metal Oxide in Selective Oxidation of Acrolein (아크롤레인 선택 산화반응에서 Mo-V-O와 금속산화물의 상간협동)

  • Park, D.W.;Na, S.E.;Kim, K.H.;Lee, W.H.;Chung, J.S.
    • Applied Chemistry for Engineering
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    • v.5 no.2
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    • pp.327-336
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    • 1994
  • The synergistic effects in mechanical mixture catalysts of Mo-V-O and metal oxide were investigated for the selective oxidation of acrolein. The metal oxides used are SnO2, αSb2O4, WO3, αAl2O3, CuO, MnO2, Cu2O, MgO, CoO, and ZnO. Mechanical mixtures of Mo-V-O plus SnO2 or αSb2O4 had resulted in higher conversion of acrolein and higher yield of acrylic acid than Mo-V-O. The origin of the synergy is attributed to the cooperation of Mo-V-O and SnO2 or αSb2O4, in which SnO2 or αSb2O4 forms dissociated oxygens at their oxygen vacancies and transports them to Mo-V-O. Cu2O, MgO, CuO, and MnO2, increased conversion of acrolein but decreased yield of acrylic acid. CoO and ZnO inhibited the catalytic performance of Mo-V-O. The different role of these metal oxides is explained in terms of their oxidation-reduction properties.

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Structures and Double Layer Performances of Carbons Pyrolized from Carbon Oxides (산화탄소로부터 열분해한 탄소의 구조 및 전기이중층 거동)

  • Kim, Ick-Jun;Yang, Sunhye;Jeon, Min-Je;Moon, Seong-In;Kim, Hyun-Soo;An, Kye-Hyeok
    • Applied Chemistry for Engineering
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    • v.18 no.5
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    • pp.522-526
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    • 2007
  • Structural features and electrochemical performances of cokes pyrolized from oxidized cokes were examined, and compared with KOH-activated coke. Needle cokes (d002=3.5\AA), having a graphene layer structure, were changed to a single phase of graphite oxide after oxidation treatment with an acidic solution having an NaCLO3/needle coke composition ratio of above 7.5, and the inter-layer distance of the oxidized coke was expanded to 6.9\AA with increasing oxygen content. After heating at 200C, the oxidized coke was pyrolized to the graphene layer structure with inter-layer distance of 3.6\AA. However, the change of the inter-layer distance of the needle coke was not observed in the KOH activation process. On the other hand, an intercalation of electrolyte ions into the pyrolized coke, observed at first charge, occurred at 1.0 V, in which the value was lower than that of KOH-activation coke. The cell capacitor using pyrolized coke exhibited a lower internal resistance of 0.57Ω in 1 kHz, and a larger capacitance per weight and volume of 30.3 F/g and 26.9 F/ml at the two-electrode system in the potential range 0~2.5 V than those of the cell capacitor using KOH-activation of coke. This better electrochemical performance may be associated with structure defects in the graphene layer derived from the process of the inter-layer expansion and shrinkage.

Analysis of the Optimal Degree and Order of Spherical Harmonics for the GNSS Receiver Antenna's PCV Correction (GNSS 수신기 안테나의 PCV 보정 모델 산출을 위한 구면조화함수 최적차수 분석)

  • Kim, Jin Yi;Won, Ji Hye;Park, Kwan Dong;Seo, Seung Woo;Park, Heung Won
    • Journal of Korean Society for Geospatial Information Science
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    • v.22 no.3
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    • pp.113-119
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    • 2014
  • The positioning accuracy of GNSS surveys deteriorates due to various error factor, and many users sometimes ignore Phase Center Variation (PCV) of antennas. IGS provides an ANTEX file which contains PCV correction information to correct for PCVs. But it is not directly applicable because PCV correction information is provided at 5-degree intervals in the azimuth and elevation directions for the case of receiver antennas, and at 1-degree intervals in the nadir angle for the case of satellite antennas. So, we devised new and optimal ways of interpolating PCV in any desired line of sight to the GNSS satellite. We used spherical harmonics fitting methods in terms of the azimuth and elevation angle for interpolation, and found an optimal degree and order. It is shown that the best accuracy was obtained from the 8 by 8 spherical harmonics. If one requires lower burden on computing resources, the order and degree less than 8 could produce resonable accuracy except for 1st and 5th order.

Analysis of Characteristics and Symptoms in Home-Based Hospice-Palliative Care Patients Registered at Local Public Health Centers (일 지역 보건소 등록 호스피스 완화돌봄 대상자의 특성 및 증상 분석)

  • Choi, Soon-Ock;Kim, Sook-Nam
    • Journal of Hospice and Palliative Care
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    • v.18 no.4
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    • pp.329-334
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    • 2015
  • Purpose: This study was aimed at analyzing the characteristics and symptoms in home-based hospice-palliative care (HBHPC) patients registered at local public health centers. Methods: A retrospective study was performed; Data of 144 HBHPC patients registered at six public health centers in Pusan City were analyzed, including their initial visit records (registration cards, initial pain evaluation and symptom evaluation). Results: The average age of the patients was 67.7 years old. Among all, 46.2% of the patient lived alone, and 65% had middle school education or lower. The most popular (36.3%) religion was Buddhism, and 47.5% received medical assistance from the government. The most frequent diagnosis was lung cancer followed by stomach cancer and liver cancer in that order. Of all, 48.9% were functionally too weak to lead a daily life, 39.6% were under cancer treatment when registered at the public health center, and 84.5% were aware of the fact that they have reached the terminal phase. Moreover, 83.6% complained about pain, and the pain level was moderate or severe in 36.5% of them. Besides pain, fatigue was the most complained symptom (84.7%), and 49.3% of them rated their fatigue as moderate or severe. Conclusion: Most of the HBHPC patients were socio-economically underprivileged and complained about moderate or worse pain and symptoms. Therefore, it appears necessary to develop an integrated strategy that is tailored for each patient reflecting their characteristics.

Evaluation of the Properties of an Environment-Friendly De-icing Agent Based on Industrial By-Products (산업부산물을 활용한 친환경제설제의 특성평가)

  • Heo, Hyung-Seok;Lee, Byung-Jae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.21 no.6
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    • pp.132-139
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    • 2017
  • A huge amount of de-icing agent is sprayed during winter to promote traffic safety in cold regions, and the quantity of de-icing agent sprayed has increased each year. The main ingredients in commonly used de-icing agents are chlorides, such as calcium chloride(CaCl2) and sodium chloride(NaCl). While calcium chloride is mostly used in Korea and sodium chloride is usually used in the U.S. and Japan, all de-icing agents include chloride ions. The chlorides included in sprayed calcium chloride-based de-icing agents have severe adverse effects, including the corrosion of reinforcing steels through salt damage by infiltrating into road structures, reduced structural performance of pavement or damage to bridge structures, and surface scaling, in combination with freezing damage in winter, as well as water pollution. In addition, the deterioration of paved concrete road surface that occurs after the use of calcium chloride-based de-icing agent accelerates the development of visual problems with traffic structures. Therefore, the present study was performed to prepare an environment-friendly liquid de-icing agent through a reaction between waste organic acids and calcium-based by-products, which are industrial by-products, and to analyze the properties of the de-icing agent in order to evaluate its applicability to road facilities.

Effects of Recombinant Human Epidermal Growth Factor on the Proliferationand Radiation Survival of Human Fibroblast Cell Lines in Vitro (재조합 표피성장인자가 방사선이 조사된 섬유아세포 증식에 미치는 영향)

  • Kim, Hyun-Sook;Kang, Ki-Mun;Lee, Sang-Wook;Na, Jae-Boem;Chai, Gyu-Young
    • Radiation Oncology Journal
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    • v.24 no.3
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    • pp.179-184
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    • 2006
  • [ Purpose_ ]: To explore the effect of recombinant human EGF on the proliferation and survival of human fibroblast cell lines following irradiation. MaterialsandMethods_: Fibroblast was originated human skin and primary cultured. The trypan blue stain assay and MTT assay were used to study the proliferative effects of EGF on human fibroblast cell lines in vitro. An incubation of fibroblasts with rhEGF for 24 hours immediately after irradiation was counted everyday. Cell cycle distributions were analyzed by FACS analysis. Results_: Number of fibroblast was significantly more increased rhEGF (1.0 nM, 10 nM, 100 nM, 1,000 nM) treated cell than control after 8 Gy irradiation. Most effective dose of rhEGF was at 160 nM. These survival differences were maintained at 1 week later. Proportion of S phase was significantly increased on rhEGF treated cells. Conclusion_: rhEGF cause increased fibroblast proliferation following irradiation. We expect that rhEGF was effective for radiation induced wound healing.

Design of Brushless Permanent Machine with Skewed Stator for Electrical Power Steering System (전동 조향 장치용 브러쉬리스 영구자석 전동기의 스테이터 스큐 설계)

  • Lee, Choong-Sung;Jung, Kyung-Tae;Hong, Jung-Pyo;Kim, Hae-Joong;Kim, Young-Kyun
    • Journal of the Korean Magnetics Society
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    • v.25 no.6
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    • pp.189-197
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    • 2015
  • As enforced the regulation of fuel efficiency, the electrification of automotive components in internal combustion vehicle has been applied instead of hydraulic pressure. A typical example of such parts is the EPS (electric power steering), and it is applied to most automotive at present. In electric power steering system, the core component is motor. The reduction of cogging torque and torque ripple is required to improve steering feeling and reduce NVH (Noise Vibration Harshness) in EPS. Generally the skewed design of stator or rotor is applied in order to reduce cogging torque and torque ripple. This paper propose the design and analysis methodology of Brusheless PMSM (Permanent Magnet Synchronous Motor) which is applied to skewed stator. The proposed methodology is as follows: First Intial Design PMSM with skewed stator for EPS, Second Optimal design using RSM (Response surface method), Third Performance Analysis such as Phase Back EMF, Inductance, Load torque using FEA (Finite Element Method). Finally, the reliability of proposed design methodology will be verified through the experiments of prototype sample.

Synthesis of a Perfluoropolyether Intermediate via Electrophilic Fluorine-Substituting Direct Fluorination (친전자성 불소치환 직접플루오르화 반응에 의한 Perfluoropolyether 중간체의 합성)

  • Yun, Seok-Min;Lim, Jae-Won;Jeong, Eui-Gyung;Park, In-Jun;Lee, Young-Seak
    • Polymer(Korea)
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    • v.35 no.2
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    • pp.166-170
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    • 2011
  • This study reported the synthesis of perfluoropolyether intermediate (TP-COOCF3) having a CF3 functional group via electrophilic fluorine substituting direct fluorination from PFPE intermediate (TP-COOCH3) having a CH3 functional group, which was synthesized by the ring opening polymerization and methyl esterification of HFPO. The effects of reaction conditions such as the amount of solvent, fluorine partial pressure, reaction time, were investigated. The results showed that the yield of fluorination reaction became the highest when the reaction was carried out in a mild condition for a long reaction time, which also minimized side reactions. The sample was characterized by FTIR and NMR, which confirmed the synthesis of the final product, TP-COOCF3, via direct fluorination converting CH3 of TP-COOCH3 to CF3 of TP-COOCF3 with 95.4% yield.

A Study on the Expansion of the Function of the Archives to the Agency Archives (기관 아카이브로의 기록관 기능 확대 방안 연구)

  • Ju, Hyun-Mi;Kim, Ik-Han
    • Journal of Korean Society of Archives and Records Management
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    • v.18 no.1
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    • pp.129-154
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    • 2018
  • It is time to prepare for the imminent development from the field of records management through decentralization to the records management of the new age in accordance with the flow of decentralization. To overcome a centralized record management system, more archives should be established to realize autonomous and decentralized records management. In accordance with the shift to a full-scale electronic record management environment, the appropriateness and effectiveness of the three-phase system of processing-archival-permanent record management based on physical transfer should be reviewed in terms of transfer cost and work efficiency. The archives should function as institutional archives to carry out the continuous volume record management and the autonomous record management at the institution level. This study examined the possibilities and implications of the archives to expand their functions as archives of institutions for the decentralization of record management and information governance orientation. In addition, the study diversified the types of records management institutions as a way to accomplish this and determined a way to design the functions of archives that integrate the current-end-end-end records management. At each level, institutions should set up archives based on their circumstances and aim at information governance at the level of each archive. Moreover, each archive level should establish a horizontal network to govern record information management.

Characteristics of TiN Barrier Metal Prepared by High Density Plasma CVD Method (고밀도 플라즈마 CVD 방법에 의한 TiN barrier metal 형성과 특성)

  • Choe, Chi-Gyu;Gang, Min-Seong;O, Gyeong-Suk;Lee, Yu-Seong;O, Dae-Hyeon;Hwang, Chan-Yong;Son, Jong-Won;Lee, Jeong-Yong;Kim, Geon-Ho
    • Korean Journal of Materials Research
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    • v.9 no.11
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    • pp.1129-1136
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    • 1999
  • TIN films were prepared on Si(100) substrate by ICP-CVD(inductive1y coupled plasma enhanced chemical vapor deposition) using TEMAT(tetrakis ethylmethamido titanium : Ti[N(CH)3C2H5]4) precursor at various deposition conditions. Phase, microstructure, and the electrical properties of TIN films were characterized by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM) and electrical measurements. Polycrystalline TiN films with B1 structure were grown at temperatures over 200C. Preferentially oriented along TiN(111) films were obtained at temperatures over 300C with the flow rates of 10, 5, and 5 sccm for TEMAT, N2 and Ar gas. The TiN/Si(100) interface was flat and no chemical reaction between TIN and SiO2 was found. The resistivity, carrier concentration and the carrier mobility for the TiN sample prepared at 500C are 21 μΩcm, 9.5×1018cm3 and 462.6cm2/Vs, respectively.

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