• 한국환경과학회지
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• 제30권6호
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• pp.501-505
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• 2021

V₂O₅-TiO₂ catalysts were prepared by various methods. V₂O₅-TiO₂ were prepared by sol-gel method with different drying conditions (aerogel and xerogel), and V₂O₅ supported on TiO₂ obtained by sol-gel method with precipitation-deposition method and impregnation method. The performance of the V₂O₅-TiO₂ catalysts was investigated for the selective oxidation of hydrogen sulfide in the stream containing both ammonia and excess water. All the catalysts showed good dispersion of vanadium and they had high H₂S conversion with no or little production of sulfur dioxide. The V₂O₅-TiO₂ aerogel catalyst prepared by sol-gel method with drying under super critical condition had the highest surface area which led to better catalytic activity compared to those by other synthesis methods.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.507-510
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• 2000

The purpose of this study is to research and developV$_2$O$_{5}$-SP270 composite electrode for supercapacitor. Property of an electrical double layer capacitor depend both on the technique used to prepare the electrode and on the current collector structure. The study is to research that V$_2$O$_{5}$-carbon composite electrode for supercapacitor with different voltage range. Suprcapacitor cell of V$_2$O$_{5}$-SP270 composite electrode with 25PVDFLiC1O$_4$PC$_{10}$ polymer electrolyte bring out good capacitor performance below 3V. The discharge capacitance of SP270 in 1st cycles was 13F/g at 0.1mA/cm$^2$, 3V. We performed cycle voltammogram, charge/discharge property.y.rty.y.

• 아시안잔디학회지
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• 제22권1호
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• pp.75-84
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• 2008

본 연구는 한지형 잔디 조성시 잔디 식생층에 혼합되고 있는 유기물 대용으로 옥수수 전분을 주성분으로 제조된 토양 보습제를 사용할 경우 조성 효율 및 토양 수분 보유능력을 평가해 보고자 수행되었다. 처리는 모래+유기물 (5%, v/v) 혼합 대조구, 모래+CAP $20g{\cdot}m^{-2}$ 혼합 처리구, 모래+CAP $20g{\cdot}m^{-2}$+유기물(5%, v/v) 혼합 처리구, 모래+CAP $40g{\cdot}m^{-2}$+유기물(5%, v/v) 혼합 의 4처리로 하였다. 파종 후 1개월 후 피복률은 모래+유기물+CAP $20g{\cdot}m^{-2}$ 및 CAP $40g{\cdot}m^{-2}$ 처리구가 50%로 나타나 유기물 단용 및 CAP 단용 처리구 36.7%에 비해 높은 피복률을 보였다. 또한 CAP 단용 처리구가 유기물 단용 처리구와 같은 수준의 피복률을 보인 것으로 보아 CAP 처리는 유기물 처리와 유사한 효과가 있는 것으로 생각된다. 분얼경당 평균 건물중은 파종 1개월 후 조사에서 모래+유기물+CAP $20g{\cdot}m^{-2}$ 및 CAP $40g{\cdot}m^{-2}$ 혼합 리구가 유기물 단용 및 CAP 단용 처리구에 비해 높게 조사되었으며 통계적으로 유의한 차이가 나타났다. 수분장력은 관수를 실시하는 기간에는 처리간에 변화가 없었으나, 건조기에는 수분 장력이 낮게 나타나 보습 효과가 있는 것으로 나타났으나 보다 정확한 결과를 위해서는 추가적인 조사가 필요하다고 생각된다. 상기 결과로 볼 때 모래+유기물+CAP $20g{\cdot}m^{-2}$ 및 CAP $40g{\cdot}m^{-2}$ 토양 혼합처리는 켄터키 블루그래스 및 퍼레니얼 라이그래스의 초기 피복률 증대에 효과적인 것으로 나타났다.

• 전기전자학회논문지
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• 제24권3호
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• pp.859-866
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• 2020

본 논문에서는 2.9 V ~ 5.6V의 넓은 입력 전압 범위를 가지는 웨어러블 AMOLED용 2-채널 DC-DC 변환기를 설계한다. 양전압 V_POS는 과도한 입력전압이 인가된다 하더라도 정상 출력 전압을 생성되는 OPC를 내장하고, 경부하 효율을 제고하기 위한 SPWM-PWM 듀얼모드 및 파워 트랜지스터 3-분할을 적용한 부스트 변환기로 설계한다. 음전압 V_NEG는 전력 효율을 높이기 위해 0.5x 인버팅 차지펌프를 이용해 설계한다. 제안된 DC-DC 변환기는 0.18-㎛ BCDMOS 공정으로 설계하였다. DC-DC 변환기는 2.9V~5.6V의 입력 전압에 대해 4.6V의V_POS와 -0.6V~-2.3V의 V_NEG 전압을 생성한다. 또한 1mA~70mA 부하전류에서 49%~92%의 전력효율과 최대 20mV의 출력 리플을 가졌다.

• 한국항행학회논문지
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• 제27권6호
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• pp.861-864
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• 2023

Recently, V2X (vehicle-to-everyting) communication has established itself as an essential technology for cooperative autonomous driving. V2X communication currently includes DSRC (dedicated short range communication) communication technology, which is a WLAN (wireless local area network) based communication technology, and C-V2X (cellular-V2X) communication technology, which is a Cellular-based communication technology. Since these two communication methods are not compatible with each other, various studies and experiments are being conducted to select one of the two communication methods. In the case of C-V2X communication, there are LTE-V2X (long term evolutionV2X) communication technology, which is an initial version, and 5G-V2X communication technology, which is a next-generation version. 5G-V2X communication technology has been completed only until standardization, so LTE-V2X communication technology is mainly used. In this paper, we introduce trends related to various issues in V2X communication, including communication method decisions.

• 한국세라믹학회지
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• 제38권4호
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• pp.308-313
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• 2001

We report the effects of the V$_2$O$_{5}$ additive on the sintering behavior and microwave dielectric properties of ZnNb$_2$O$_{6}$ ceramics. Densification temperatures of V$_2$O$_{5}$-doped ZnNb$_2$O$_{6}$ samples are lowered to the range of 875-9$25^{\circ}C$ because of the liquid phase sintering. Doped samples are composed of a Zn(Nb,V)$_2$O$_{6}$ solid solution and second phases. Up to 5 wt% V$_2$O$_{5}$ is the only second phase, however, V$_2$O$_{5}$ also exists as the second phase for 10 wt% V$_2$O$_{5}$ addition. In comparison with reported values of undoped ZnNb$_2$O$_{6}$ ceramics, microwave properties of V$_2$O$_{5}$-doped ZnNb$_2$O$_{6}$ samples are seriously degraded, which is confirmed to originate from the second phases. The optimum microwave properties (Q$\times$f=13,800, $\varepsilon$$_{r}$=23, $\tau$$_{f}$=-66ppm/$^{\circ}C$) are obtained from ZnNb$_2$O$_{6}$ with the addition of 5 wt% V$_2$O$_{5}$ sintered at 90$0^{\circ}C$.90$0^{\circ}C$.EX>.

• E2M - 전기 전자와 첨단 소재
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• 제9권7호
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• pp.690-695
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• 1996

We have systematically investigated the characterization of V$_{2}$O$_{5}$ thin films as a counter electrode for lithium based complementary electrochromic devices. The V$_{2}$O$_{5}$ thin films were prepared by thermal vacuum evaporation with varing the substrate temperature and film thickness. In electrochromic devices for smart windows, the WO$_{3}$ thin films with 400-800 nm thickness require to be capable of reversibly injection 10-15 mC/cm$^{2}$ of lithium, which is readily accomplished charge-balanced switching in a V$_{2}$O$_{5}$ thin films with 100-150nm thick. The V$_{2}$O$_{5}$ thin films produces considerably small changes in optical modulation properties in the visible and near infrared region(500-1100 nm) compared to the amorphous WO$_{3}$ thin films on 10-15 mC/cm$^{2}$ of lithium injection and the V$_{2}$O$_{5}$ thin films can therefore act as a counter electrode to WO$_{3}$ in a lithium based complementary clectrochromic devices. After 10$^{5}$ coloration/bleaching switching time, the degradation does not occurs and the devices exhibit a stable optical modulation in V$_{2}$O$_{5}$ thin films. It has shown that the injected lithium ion amounts in crystalline V$_{2}$O$_{5}$ thin films with the same thickness is large by 3-5 mC/cm$^{2}$ of lithium compared to the amorphous thin films in the same driving conditions. Therefore, to optimize the device performance, it is necessary to choose an appropriate film thickness and crystallinity of V$_{2}$O$_{5}$ for amorphous WO$_{3}$ film thickness as a working electrode.

• Korean Chemical Engineering Research
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• 제49권2호
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• pp.175-180
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• 2011

본 연구에서는, 전자의 재결합을 감소시켜 염료 감응형 태양전지의 효율을 향상시키고자 다른 에너지 준위를 갖는 $TiO_{2}$와 $V_{2}O_{5}$을 혼합하여 $TiO_{2}/V_{2}O_{5}$ 혼성반도체를 제조하였다. 또한 제조된 $TiO_{2}/V_{2}O_{5}$ 혼성반도체는 페인트 쉐이커를 이용하여 회쇄 후 염료 감응형 태양전지의 제조 및 전기화학적 특성 평가를 함으로써 $V_{2}O_{5}$ 혼합 및 회쇄 효과가 전지효율에 미치는 영향을 고찰하였다. I-V 곡선을 통하여 측정된 염료 감응형 태양전지의 효율은 $V_{2}O_{5}$ 혼합 및 회쇄 효과에 의하여 2.9에서 5.7%로, $TiO_{2}$ 염료 감응형 태양전지에 비하여 약 2배 증가하였다. 이러한 결과는 $TiO_{2}$의 전도대보다 낮은 전도대를 갖는 $V_{2}O_{5}$의 도입으로 효과적으로 전자를 FTO 유리에 전달하여, 전자가 염료 및 전해질과의 재결합을 감소하게 되어 에너지 전환효율이 증가된 것으로 여겨 진다. 또한, 임피던스 결과도 회쇄된 $TiO_{2}/V_{2}O_{5}$ 혼성 반도체의 효과를 나타내는 $TiO_{2}$/염료/전해질 계면의 저항감소를 보여 주었다.

• Molecules and Cells
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• 제43권11호
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• pp.953-963
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• 2020

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an infectious disease with multiple severe symptoms, such as fever over 37.5℃, cough, dyspnea, and pneumonia. In our research, microRNAs (miRNAs) binding to the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory-related coronavirus (MERS-CoV), and SARS-CoV-2 were identified by bioinformatic tools. Five miRNAs (hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-16-5p, and hsa-miR-196a-1-3p) were found to commonly bind to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also identified miRNAs that bind to receptor proteins, such as ACE2, ADAM17, and TMPRSS2, which are important for understanding the infection mechanism of SARS-CoV-2. The expression patterns of those miRNAs were examined in hamster lung samples infected by SARS-CoV-2. Five miRNAs (hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-221-3p, hsa-miR-140-3p, and hsa-miR-422a) showed differential expression patterns in lung tissues before and after infection. Especially, hsa-miR-15b-5p and hsa-miR-195-5p showed a large difference in expression, indicating that they may potentially be diagnostic biomarkers for SARS-CoV-2 infection.

• 한국결정학회지
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• 제15권1호
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• pp.35-39
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• 2004

Two new nickel vanadium borophosphate cluster compounds, $(NH_4)_{10}[Ni(H_2O)_5]_4[V_2P_2BO_{12}]_6{\cdot}nH_2O$ (1) and $(NH_4)_{3.5}(C_3H_{12}N_2)_{3.5}[Ni(H_2O)_6]_{1.25}{[Ni(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}nH_2O$ (2) have been synthesized and structurally characterized. Inter-diffusion methods were employed to prepare the compounds. The cluster anion $[(NH_4)\;{\supset}\;V_2P_2BO_{12}]_6$ is used as a building unit in the synthesis of new compounds containing $Ni(H_2O){^{2+}_5}$ in the presence of pyrazine and 1,3-diaminopropane. Compounds contain isolated cluster anions with general composition ${[Ni(H_2O)_5]_n[(NH_4)\;{\supset}\;V_2P_2BO_{12}]_6}^{-(17-2n)}$ (n = 2, 4). Crystal data: $(NH_4)_{10}[Ni(H_2O)_5]_4[V_2P_2BO_{12}]_6{\cdot}nH_2O$, monoclinic, space group C2/m (no. 12), a = 27.538(2) ${\AA}$, b = 20.366(2) ${\AA}$, c = 11.9614(9) ${\AA}$, ${\beta}$ = 112.131(1)$^{\circ}$, Z = 8; $(NH_4)_{3.5}(C_3H_{12}N_2)_b[Ni(H_2O)_6]_{3.5}{[Ni(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}nH_2O$, triclinic, space group P-1 (no. 2), a = 17.7668(9) ${\AA}$, b = 17.881(1) ${\AA}$, c = 20.668(1) ${\AA}$, ${\alpha}$ = 86.729(1)$^{\circ}$, ${\beta}$ \ 65.77(1)$^{\circ}$, ${\gamma}$ = 80.388(1)$^{\circ}$, Z = 2.