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Removal Technology of NOx Using V2O5/TiO2 Catalyst Impregnated Ceramic Candle Filters (바나디아 촉매담지 세라믹 캔들필터를 이용한 질소산화물 제거기술)

  • Lee, Dong-Sub;Park, Jin-Sick
    • Journal of Environmental Science International
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    • v.16 no.9
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    • pp.1077-1083
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    • 2007
  • [ $V_2O_5/TiO_2$ ] catalyst impregnated ceramic candle filters are in principle, capable of performing shallow-bed dust filtration plus a catalytic reaction, promoted by a catalytic deposited in their inner structure. Pilot-scale $V_2O_5/TiO_2$ catalyst impregnated ceramic candle filters were prepared, characterized and tested for their activity towards the SCR reaction. The effect on NO conversion of operating temperature, gas hourly space velocity, amount of deposited catalyst, pressure drops and long-term experiment (life of catalytic filter) was determined. The following effects of $V_2O_5/TiO_2$ catalyst impregnated ceramic candle filters in SCR reaction are observed: (1) It increases the activity and widens the temperature window for SCR. (2) When the content of $V_2O_5$ catalyst increases further from 3 to 9wt.%, activity of NO increases. (3) NO conversion at first increases with temperature and then decreases at high temperatures (above $400^{\circ} over), possibly due to the occurrence of the ammonia oxidation reaction.

The Effect of V2O5 on the Dielectric and Piezoelectric Characteristics of Pb(Sb1/2Nb1/2)O3-Pb(Ni1/3Nb2/3)O3-Pb(Zr, Ti)O3Ceramics (V2O5가 Pb(Sb1/2Nb1/2)O3-Pb(Ni1/3Nb2/3)O3-Pb(Zr, Ti)O3세라믹스의 유전 및 압전특성에 미치는 영향)

  • 류주현;남승현;이수호
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.8
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    • pp.676-680
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    • 2003
  • In this study, to develop the low temperature sintering ceramics for piezoelectric transformer, PSN-PNN-PZT system ceramics were manufactured as a function of V$_2$O$_{5}$ addition, that is the low melting point oxide. Its dielectric and piezoelectric characteristics were investigated. With increasing the amount of V$_2$O$_{5}$ addition, electromechanical coupling factor(kp) and mechanical quality factor(Qm) were decreased. For piezoelectric transformer application, the 0.1wt% V$_2$O$_{5}$ added specimen sintered at 1,00$0^{\circ}C$ showed the proper value of $\varepsilon$r=1,590, kp=0.51 and Qm=748.m=748.

Studies on Electrocardiogram of the Normal Korean Native Goat II. Waveforms and Amplitudes of the Unipolar Precordial Chest Leads (정상적인 한국 흑염소의 심전도에 관한 연구 II. 담부단극유도의 파형과 전위)

  • 최인혁;김기주;윤여백;서석열;김남수
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.338-348
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    • 1997
  • The electrocardiographic (ECG) parameters on unipolar precordial chest leads in the normal Korean native goat of 343 heads as to CV$_{6}$LU, CV$_{6}$LL CV$_{6}$RU, CV$_{6}$RL and V10 have been measured with a 3-channel Elertrocardiograph and computed, analysed. All wave types as positive, negatives biphasic and flatting in the P and T waves appeared in all leads but any special wave type was not shown more than 60%. Average amplitudes with the highest frequent rate in P wave were 81.4$\pm$32.0 $\mu $V (52.3%), 59.6$\pm $ 27.5 $\mu $V (50.5 %) of Positive type in leads CV$_{6}$LU and CV$_{6}$LL, and -5fl.5$\pm $22.6 $\mu $V (44.0%) of negative type in leads VIO, and 51.3% and 44% of flatting type in leads CV$_{6}$RU and CV$_{6}$RL, but flatting type of clinic form appeared frequent rate between 53% and 77% in all leads. In T wave, average amplitudes with the highest frequent rate were 265.0$\pm $97.1 $\mu $V (54.0%) and 212.2$\pm $90.7 $\mu $V (57.0%) of positive type in leads CV$_{6}$LL and CV$_{6}$RL, and -252.8$\pm $90.7 $\mu $V (56.6%) of negative in lead V10, but amplitudes of T waves that positive and negative type appeared similarity frequent ra蛇 ware 208.7$\pm $99.7 $\mu $V (42.1%), -159.0$\pm $81.6 (43.8%) in lead CV$_{6}$LU and 153.2$\pm $139.0 $\mu $V (47.3%), -130.0$\pm $81.4 (43.2%) in lead CV$_{6}$RU, Amplitudes of QRS complex wave forms showed the highest frequent rate were 218.2$\pm $96.4 $\mu $V (47.8%), 308.3$\pm $135.2 $\mu $V (46.8 %), 232.8$\pm $126.5 $\mu $V (58.5%) and 225.3$\pm $89.6 $\mu $V (54.9%) of R type in the leeds CV$_{6}$LU, CV$_{6}$LL, CV$_{6}$RU and CV$_{6}$RL, and were -92.5$\pm $79.1 $\mu $V,479.0 $\pm $116.6 $\mu $V (33.2%) and 212.1 $\pm $86.7 $\mu $V (32.8%) of QR and 05 type in the lead V10. These results in the V10, CV$_{6}$RU, CV$_{6}$RL, CV$_{6}$LU, CV$_{6}$LL. may be not starve to purpose of unipolar precordial chest leads.

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Preparation of $WO_3/TiO_2$ and $V_2O_5/TiO_2$ powders and their catalytic performances in the SCR of $NO_x$ ($WO_3/TiO_2$$V_2O_5/TiO_2$ 분말의 합성 및 $NO_x$ 제거 SCR특성)

  • Lee, Tae-Suk;Lee, In-Gyu;Lee, Byeong-Woo;Shin, Dong-Woo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.16 no.5
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    • pp.216-221
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    • 2006
  • An investigation of the influence of $WO_3$ and $V_2O_5$ catalysts on the microstructure, phase formation and selective catalytic reduction (SCR) efficiency of the synthesized SCR powders has been carried out. A commercial anatase-$TiO_2$ was used as the catalysts support. For $WO_3(10wt%)/TiO_2$, the W loading to the $TiO_2$ support led to the lower in anatase to rutile transition temperature from $1200^{\circ}C$ of $TiO_2$ support to ${\sim}900^{\circ}C$. The transition temperature was also lowered to below $650^{\circ}C$ in the $V_2O_5$(5 and 10 wt%) added composition. The $WO_3(10wt%)/TiO_2$ SCR powder obtained at $450^{\circ}C$ showed near 100% of $NO_x$ conversion efficiency at $350{\sim}400^{\circ}C$ and for the powder prepared at $650^{\circ}C$ the same efficiency was achieved in wider temperature range $300{\sim}400^{\circ}C$. The highest $NO_x$ conversion efficiency of 100% was obtained in the $V_2O_5(5wt%)/TiO_2$ SCR composition calcined at $650^{\circ}C$ in the relatively wider temperature range $250{\sim}350^{\circ}C$, while the catalytic efficiency considerably decreased for the $V_2O_5(10wt%)/TiO_2$. The lowered conversion efficiency of $NO_x$ observed in the $V_2O_5(10wt%)/TiO_2$ composition calcined at $650^{\circ}C$ was considered to be correlated with the lowered surface area resulting from the increased crystallite growth by highly reactive vanadium loading.

A study on Fabrication of Ferroelectric SST Thin Films by Liquid Delivery MOCVD Process (Liquid Delivery MOCVD공정을 이용한 강유전체 SBT 박막의 제조기술에 관한 연구)

  • Kang, Dong-Kyun;Paik, Seung-Kyu;Kim, Hyoeng-Ki;Kim, Byong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.111-115
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    • 2003
  • 200nm 정도의 두께를 가진 SBT 박막이 liquid delivery MOCVD 공정에 의해 (111) oriented Pt/Ti/$SiO_2$/Si 기판 위에 증착되었다 이 실험에서는 $Sr(TMHD)_2$tetraglyme, $Bi(ph)_3$ 그리고 $Ta(O^iPr)_4$(TMHD)를 출발 물질로 사용하였다. Sr 출발 물질의 열적 안정화를 위해서 adduct로 tetraglyme를 사용하여 실험하였고 유기 용매로는 n-butyl acetate를 사용하였다 Substrate temperature와 reactor pressure는 각각 $570^{\circ}C$와 5Torr로 유지시켰다. 또한 vaporizer의 용도는 $190-200^{\circ}C$, 그리고 delivery line 의 온도는 vaporizer 보다 높게 유지 $(220-230^{\circ}C)$하여 출발 용액을 분당 0.1ml로 50분간 주입하였다. 수송가스로 Ar, 산화제로 $O_2$ 가스를 사용하였다. 제조한 SBT 박막은 $750^{\circ}C$에서 열처리한 후 인가전압 3V와 5V에서 $2P_r$값이 각각 6.47, $8.98{\mu}C/cm^2$이었으며, $2E_c$값은 인가전압 3V와 5V에서 각각 2.05, 2.31V이었다 그리고 $800^{\circ}C$에서는$750^{\circ}C$에서 열처리한 SBT 박막보다 다소 우수한 이력특성을 나타내어 $2P_r$ 값은 인가전압 3V와 5V에서 각각 7.59, $10.18{\mu}C/cm^2$ 이었으며, $2E_c$값은 인가 전압 3V와 5V에서 각각 2.00, 2.21V 이었다.

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Separation Characteristics of Barium Ion in Water Using Capacitive Deionization (CDI) Process (축전식탈염(CDI) 공정을 이용한 수용액 중 바륨 이온 분리 특성 연구)

  • Nam, Dong Hyun;Rhim, Ji Won
    • Membrane Journal
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    • v.29 no.6
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    • pp.355-361
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    • 2019
  • We studied the removal of barium ions that may be contained in industrial wastewater using the existing capacitive deionization (CDI). The 30 mg/L BaCl2 (barium chloride dihydrate) solution was used as the feed solution, and the flow rate was set to 10 mL/min. The adsorption conditions were varied from 1.2 V to 3, 5 and 7 min, and the desorption conditions were -1, -1.5, -2 V and 1, 2 and 3 min, respectively, to select the most efficient conditions. As a result, barium ion removal efficiency of 64.4% was obtained under the adsorption conditions of adsorption of 1.2 V/7 min and the desorption -1 V/1 min. For the desorption voltages and time, under the same experimental conditions, the removal efficiency of CDI for 30 mg/L NaCl aqueous solution with the same concentration as barium showed 69.9% removal efficiency under the adsorption conditions of and the desorption conditions of 1.2 V/7 min desorption -1 V/1 min, respectively.

Electrical Properties of $V_2O_5$ Thin Films for the uncooled Infrared Detector (비냉각 적외선 감지소자 응용을 위한 $V_2O_5$ 박막의 전기적 특성)

  • Nam, Sung-Pill;Lee, Sung-Gap;Bea, Seon-Gi;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2007.11a
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    • pp.116-117
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    • 2007
  • The $V_2O_5$ thin films deposited on Pt/Ti/$SiO_2$/Si substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_2O_5$ thin films annealed at $300^{\circ}C$ were 37.7, with a dielectric loss of 2.535, respectively. Also, the TCR values of the $V_2O_5$ thin films annealed at $300^{\circ}C$ were about -2.65%/K.

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Structural and electrical properties of $V_{1.8}W_{0.2}O_5$ thin films with $Ar/O_2$ Ratio ($Ar/O_2$ 비에 따른 $V_{1.8}W_{0.2}O_5$ thin film 의 구조적, 유전적 특성)

  • Lee, Seung-Hwan;Park, In-Gil;Bae, Seon-Gi;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1252-1253
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    • 2008
  • The $V_{1.8}W_{0.2}O_5$ thin films deposited on $Pt/Ti/SiO_2/Si$ substrates by RF sputtering method with different $Ar/O_2$ ratio. The $V_{1.8}W_{0.2}O_5$ thin films were measured electrical and structural properties, fairly good Temperature coefficient of resistance(TCR). It was found that electrical and structural properties, TCR properties of thin films were strongly dependent upon the $Ar/O_2$ ratio. The dielectric constant of the $V_{1.8}W_{0.2}O_5$ thin films with 50/20 ratio were 93 with a dielectric loss of 0.535, respectively. Also, the TCR values of the $V_{1.8}W_{0.2}O_5$ thin films with 50/20 ratio were -3.15%/$^{\circ}C$.

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The novel NPLVTSCR ESD ProtectionCircuit without Latch-up Phenomenon for High-Speed I/O Interface (Latch-up을 방지한 고속 입출력 인터페이스용 새로운 구조의 NPLVTSCR ESD 보호회로)

  • Koo, Yong-Seo
    • Journal of IKEEE
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    • v.11 no.1 s.20
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    • pp.54-60
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    • 2007
  • In this study novel ESD protection device, namely, N/P-type Low Voltage Triggered SCR, has been proposed, for high speed I/O interface. Proposed device could lower high trigger voltage($\sim$20V) of conventional SCR and reduce latch-up phenomenon of protection device during the normal condition. In this Study, the proposed NPLVTSCR has been simulated using TMA MEDICI device simulator for electrical characteristic. Also the proposed device's test pattern was fabricated using 90nm TSMC's CMOS process and was measured electrical characteristic and robustness. In the result, NPLVTSCR has 3.2V $\sim$ 7.5V trigger voltage and 2.3V $\sim$ 3.2V holding voltage by changing PMOS gate length and it has about 2kV, 7.5A HBM ESD robustness(IEC61000-4-2).

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Empirical Analysis on Radio Communication Range and Vehicle Ratio in V2X Environment (무선 통신 가능 범위와 V2X 차량 비율에 관한 경험적 분석)

  • Park, Sang-Ung;Kim, Joo-Young;Na, Sung-Yong;Lee, Seung-Jae
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.15 no.5
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    • pp.29-41
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    • 2016
  • V2X environment is the most popular part of the C-ITS based on the high technologies. To evaluate V2X environment technologies, radio communication range and market penetration rate of V2X vehicle are used. This paper studies the V2X environment considering various traffic congestion level, radio communication range and market penetration rate of V2X vehicle using the microscopic simulation (VISSIM) based on proper parameters and algorithm. In conclusion, V2X environment can reduce the congestion in proper traffic volume. However, if traffic volume is almost near the capacity, even V2X environment can't relieve the road condition. Furthermore, increase of the radio communication range does not always mean the decrease of the congestion and even with the small market penetration rate, it can also have an impact on the V2X environment. This result will be the foundation for the V2X environment much better.