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The Effect of Vanadium(V) Oxide Content of V2O5-WO3/TiO2 Catalyst on the Nitrogen Oxides Reduction and N2O Formation (질소산화물 환원과 N2O 생성에 있어서 V2O5-WO3/TiO2 촉매의 V2O5 함량 영향)

  • Kim, Jin-Hyung;Choi, Joo-Hong
    • Korean Chemical Engineering Research
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    • v.51 no.3
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    • pp.313-318
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    • 2013
  • In order to investigate the effect of $V_2O_5$ loading of $V_2O_5-WO_3/TiO_2$ catalyst on the NO reduction and the formation of $N_2O$, the experimental study was carried out in a differential reactor using the powder catalyst. The NO reduction and the ammonia oxidation were, respectively, investigated over the catalysts compose of $V_2O_5$ content (1~8 wt%) based on the fixed composition of $WO_3$ (9 wt%) on $TiO_2$ powder. $V_2O_5-WO_3/TiO_2$ catalysts had the NO reduction activity even under the temperature of $200^{\circ}C$. However, the lowest temperature for NO reduction activity more than 99.9% to treat NO concentration of 700 ppm appeared at 340 with very limited temperature window in the case of 1 wt% $V_2O_5$ catalyst. And the temperature shifted to lower one as well as the temperature window was widen as the $V_2O_5$ content of the catalyst increased, and finally reached at the activation temperature ranged $220{\sim}340^{\circ}C$ in the case of 6 wt% $V_2O_5$ catalyst. The catalyst of 8 wt% $V_2O_5$ content presented lower activity than that of 8 wt% $V_2O_5$ content over the full temperature range. NO reduction activity decreased as the $V_2O_5$ content of the catalyst increased above $340^{\circ}C$. The active site for NO reduction over $V_2O_5-WO_3/TiO_2$ catalysts was mainly related with $V_2O_5$ particles sustained as the bare surface with relevant size which should be not so large to stimulate $N_2O$ formation at high temperature over $320^{\circ}C$ according to the ammonia oxidation. Currently, $V_2O_5-WO_3/TiO_2$ catalysts were operated in the temperature ranged $350{\sim}450^{\circ}C$ to treat NOx in the effluent gas of industrial plants. However, in order to save the energy and to reduce the secondary pollutant $N_2O$ in the high temperature process, the using of $V_2O_5-WO_3/TiO_2$ catalyst of content $V_2O_5$ was recommended as the low temperature catalyst which was suitable for low temperature operation ranged $250{\sim}320^{\circ}C$.

Synthesis and Photovoltaic Properties of Low Band Gap π-conjugated Polymers Based on 2-pyran-4-ylidene-malononitrile Derivatives (2-pyran-4-ylidene-malononitrile을 기본으로 하는 작은 Band Gap을 가지는 공중합체의 합성 및 광전변환 특성)

  • You, Hyeri;Shin, Woong;Park, Jeong Bae;Park, Sang Jun;Lim, Jun Heok;Kim, Joo Hyun
    • Applied Chemistry for Engineering
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    • v.20 no.3
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    • pp.273-278
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    • 2009
  • A series of poly[2-(2,6-dimethylpyran-4-ylidene)malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PM-PPV), poly[2-{2,6-Bis-[2-(5-bromothiophen-2-yl)-vinyl]-pyran-4-ylidene}-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMT-PPV) and poly[2-[2,6-Bis-(2-{4-[(4-bromophenyl)-phenylamino]-phenyl}-vinyl)-pyran-4-ylidene]-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMTPA-PPV) were synthesized by the Heck coupling reaction. The band gap of PM-PPV, PMT-PPV and PMTPA-PPV were 2.18 eV, 1.90 eV and 2.07 eV, respectively. The LUMO energy levels of PM-PPV, PMT-PPV and PMTPA-PPV were 3.65 eV, 3.54 eV and 3.62 eV, respectively and the HOMO energy levels of those were 5.83 eV, 5.61 eV and 5.52 eV, respectively. The photovoltaic devices based on the polymers was fabricated. The efficiency of the solar cells based on PM-PPV, PMT-PPV and PMTPA-PPV were 0.028%, 0.031% and 0.11%, respectively and the open circuit voltage (Voc) was 0.59 V~0.69 V under AM 1.5 G and 1 sun condition ($100mA/cm^2$).

A Study of Hazard Analysis and Monitoring Concepts of Autonomous Vehicles Based on V2V Communication System at Non-signalized Intersections (비신호 교차로 상황에서 V2V 기반 자율주행차의 위험성 분석 및 모니터링 컨셉 연구)

  • Baek, Yun-soek;Shin, Seong-geun;Ahn, Dae-ryong;Lee, Hyuck-kee;Moon, Byoung-joon;Kim, Sung-sub;Cho, Seong-woo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.6
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    • pp.222-234
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    • 2020
  • Autonomous vehicles are equipped with a wide rage of sensors such as GPS, RADAR, LIDAR, camera, IMU, etc. and are driven by recognizing and judging various transportation systems at intersections in the city. The accident ratio of the intersection of the autonomous vehicles is 88% of all accidents due to the limitation of prediction and judgment of an area outside the sensing distance. Not only research on non-signalized intersection collision avoidance strategies through V2V and V2I is underway, but also research on safe intersection driving in failure situations is underway, but verification and fragments through simple intersection scenarios Only typical V2V failures are presented. In this paper, we analyzed the architecture of the V2V module, analyzed the causal factors for each V2V module, and defined the failure mode. We presented intersection scenarios for various road conditions and traffic volumes. we used the ISO-26262 Part3 Process and performed HARA (Hazard Analysis and Risk Assessment) to analyze the risk of autonomous vehicle based on the simulation. We presented ASIL, which is the result of risk analysis, proposed a monitoring concept for each component of the V2V module, and presented monitoring coverage.

Effect of V2O5 Modification in V2O5/TiO2-ZrO2 Catalysts on Their Surface Properties and Catalytic Activities for Acid Catalysis

  • Sohn, Jong-Rack;Lee, Cheul-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2459-2465
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    • 2007
  • V2O5/TiO2-ZrO2 catalyst modified with V2O5 was prepared by adding Ti(OH)4-Zr(OH)4 powder into an aqueous solution of ammonium metavanadate followed by drying and calcining at high temperatures. The characterization of prepared catalysts was performed using XRD, DSC, solid-state 51V NMR, and FTIR. In the case of calcination temperature of 500 oC, for the catalysts containing low loading V2O5 below 25 wt % vanadium oxide was in a highly dispersed state, while for catalysts containing high loading V2O5 equal to or above 25 wt % vanadium oxide was well crystallized due to the V2O5 loading exceeding the formation of monolayer on the surface of TiO2-ZrO2. The strong acid sites were formed through the bonding between dispersed V2O5 and TiO2-ZrO2. The larger the dispersed V2O5 amount, the higher both the acidity and catalytic activities for acid catalysis.

Electrochemical properties of $Li_2O-P_2O_5-V_2O_5$ Glass-ceramics by Addition of $Bi_2O_3$ ($Bi_2O_3$첨가에 따른 $Li_2O-P_2O_5-V_2O_5$ 결정화유리의 전기화학적 특성변화)

  • Son, Muong-Mo;Gu, Hal-Bon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.797-800
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    • 2002
  • Instead of a solution process producing amorphous $LiV_3O_8$ form, we prepared Lithium vanadate glass by melting $Li_2O-P_2O_5-V_2O_5$ and $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$ composition in pt. crucible and by quenching on the copper plate. From the crystallization of $Li_2O-P_2O_5-V_2O_5$ and $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$, we could abtain glass-ceramics having crystal phase, LiV3O8 from glass matrix. The material heat-treated at lower-temperature, $250^{\circ}C$ had less crystalline and lower capacity, But the material heat-treadted at higher-temperature, $330^{\circ}C$ had higher capacity and $Li_2O-P_2O_5-V_2O_5$ glass-ceramics had higher capacity than $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$ glass-ceramics.

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Development of Collision Prevention Usage Scenario based on Vehicle-to-Vehicle Communication of Autonomous Vehicles (자율주행 차량의 차량 대 차량 통신에 기반한 충돌방지 활용 시나리오 개발)

  • Seo, HyunDuk;Kwon, Doyoung;Shin, Jaemin;Choi, Eunhyuk;Lim, Huhnkuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.2
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    • pp.251-257
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    • 2022
  • Self-driving vehicles are a type of smart vehicle with the help of ICT technology, which means a vehicle that operates without the intervention of a driver.Vehicles with vehicle safety communication technology (V2X) applied use information detected from various sensors or other vehicles/infrastructures to enable the smart vehicle to accurately and quickly predict the driver's potential danger situation, contributing to more stable autonomous driving. In this paper, among V2X communication technologies, a vehicle-to-vehicle communication (V2V) simulation communication technology is used to present a scenario for preventing collisions in autonomous vehicles. A vehicle collision prevention system based on V2V simulated communication was implemented and the suggested collision prevention application scenario was demonstrated. The suggested collision prevention utilization scenario can be considered as one application case of V2V communication technologies that are currently being developed/applied.

Multi-Channel MAC Protocol Based on V2I/V2V Collaboration in VANET (VANET에서 V2I/V2V 협력 기반 멀티채널 MAC 프로토콜)

  • Heo, Sung-Man;Yoo, Sang-Jo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.1
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    • pp.96-107
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    • 2015
  • VANET technologies provide real-time traffic information for mitigating traffic jam and preventing traffic accidents, as well as in-vehicle infotainment service through Telematics/Intelligent Transportation System (ITS). Due to the rapid increasement of various requirements, the vehicle communication with a limited resource and the fixed frame architecture of the conventional techniques is limited to provide an efficient communication service. Therefore, a new flexible operation depending on the surrounding situation information is required that needs an adaptive design of the network architecture and protocol for efficiently predicting, distributing and sharing the context-aware information. In this paper, Vehicle-to-Infrastructure (V2I) based on communication between vehicle and a Road Side Units (RSU) and Vehicle-to-Vehicle (V2V) based on communication between vehicles are effectively combined in a new MAC architecture and V2I and V2V vehicles collaborate in management. As a result, many vehicles and RSU can use more efficiently the resource and send data rapidly. The simulation results show that the proposed method can achieve high resource utilization in accordance. Also we can find out the optimal transmission relay time and 2nd relay vehicle selection probability value to spread out V2V/V2I collaborative schedule message rapidly.

Solid-State $^{51}V$ NMR and Infrared Spectroscopic Study of Vanadium Oxide Supported on $TiO_2-ZrO_2$

  • Park, Eun Hui;Lee, Man Ho;Son, Jong Rak
    • Bulletin of the Korean Chemical Society
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    • v.21 no.9
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    • pp.913-918
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    • 2000
  • Vanadium oxide catalyst supported on TiO2-ZrO2 has been prepared by adding Ti(OH)4-Zr(OH)4 powder to an aqueous solution of ammonium metavanadate followed by drying and calcining at high temperatures. The char-acterization ofthe prepared catalysts was performed using solid-state 51V NMR and FTIR.In thecase ofcalci-nation temperature at 773 K, vanadium oxide was in a highly dispersed state for the samples containing low loading V2O5 below 25 wt %, but for samplescontaining high loading V2O5 equal to or above 25 wt %, vana-dium oxidewas well crystallized due to the V2O5 loading exceeding the formation of monolayer on the surface of TiO2-ZrO2.The ZrV2O7 compound was formed through the reactionof V2O5 and ZrO2 at 773-973 K, where-as the V3Ti6O17 compound was formedthrough the reaction of V2O5 and TiO2 at 973-1073 K. The V3Ti6O17 compound decomposed to V2O5 and TiO2 at 1173 K, which were confirmed by FTIR and 51V NMR.

A Study on V2V Communication Environment in K-city (자율주행 실험도시(K-city) 내 V2V 통신 환경에 관한 연구)

  • Jo, Byeongchan;Kim, Donghwan;Shin, Jaekon;Kim, Sungsub;Cho, Seongwoo
    • Journal of Auto-vehicle Safety Association
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    • v.13 no.1
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    • pp.26-30
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    • 2021
  • K-city is an experimental area for developing self-driving cars. V2X communications such as WAVE, C-V2X and 5G are an essential technology for autonomous driving above level 4. In this paper, the research on the V2V communication environment was carried out through BSM receiving level analysis on the driving route in K-city. A stationary vehicle communicated with a test vehicle moving along urban area and suburban road in two different scenarios. The communication range and receiving levels obtained from this study will be used to develop and verify various safety scenarios using V2V communication within K-city in the future.

Prototype Implementation of Control Board for Vehicle V2X Communication Performance Evaluation (자동차 V2X 통신성능 평가를 위한 제어 보드 프로토타입 구현)

  • Yoowon Kim;Byeongchan Jo;Hyuk Jung
    • Journal of Auto-vehicle Safety Association
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    • v.15 no.2
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    • pp.28-34
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    • 2023
  • The Republic of Korea aims to complete the commercialisation of Level 4+ cooperative autonomous driving in 2027. It also plans to include V2X OBU in the K-NCAP evaluation items. Therefore, communication performance safety evaluation criteria for V2X OBU need to be established, and an OBU with necessary functions is needed to develop V2X communication performance safety evaluation technology for vehicles. In this study, we implemented a V2X OBU control board prototype that can be used to develop a V2X communication performance safety evaluation technology for Level 4+ autonomous vehicles, and confirmed that the control board prototype works normally.