• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.733-736
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• 2001

Instead of a solution technigue producing amorphous LiV$_3$O$_{8}$ form, we prepared Lithium vanadate glass by melting Li$_2$O-P$_2$O$_{5}$-V$_2$O$_{5}$, composition in pt. crucible and by quenching on the copper plate. From the crystallization of Li$_2$O-P$_2$O$_{5}$-V$_2$O$_{5}$, we could abtain crystal phase, LiV$_3$O$_{8}$. The material heat-treated at lower-temperature, 25$0^{\circ}C$ was less crystalline, but had higher capacity. In present paper, we describe eletrochemical properties during crystallization process and find the best crystallization condition of Li$_2$O-P$_2$O$_{5}$-V$_2$O$_{5}$ glass as cathod material.cathod material.

• Journal of the Korean Ceramic Society
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• v.25 no.4
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• pp.335-340
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• 1988

The change in microstructure and the electrical properties of Pb(In1/2Nb1/2)O3-PbTiO3 Ceramics caused by V2O5 addition were studied. The results are ; 1. interability was increased because the mass transport through the second phase formed by V2O5 addition increased. 2. ith addition of V2O5, tetragonality and Curie temperature increased. The maximum value of kp was observed when 0.5wt% of V2O5 was added. 3. he second phase formed by V2O5 accelerated the grain growth, and existed in grain boundary. Electrical properties were changed by corelations between tetragonality and the amount of second phase.

• Journal of the Korean Ceramic Society
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• v.11 no.3
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• pp.19-26
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• 1974

Mechanical properties of the system PbO-B2O3-V2O5 low melting glass during crystallization by heat-treatment were investigated. Wettability of the system PbO-B2O3-V2O5 was excellent and appropriate for commercial sealing as a low melting solder glass. Crystals, during heat-treated at 30$0^{\circ}C$ of the system PbO-B2O3-V2O5 were $\beta$-4PbO.B2O3, 5PbO.4B2O3, and Pb2V2O7 mainly. The percent of crystallinity was 82$\pm$5%. Mechanical properties of the system PbO-B2O3-V2O5 were influenced not only by the differences of density and coefficient of thermal expansion and the stress induced from the difference in the density and coefficient of thermal expansion between glass phase and crystals but also crystallization conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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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.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4022-4029
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• 2022

We investigated the possibility of using graphene for control of hydrogen isotopes by exploring adsorption, reflection, and penetration of hydrogen isotopes on graphene using molecular dynamics. Reflection is the dominant interaction when hydrogen isotopes have low incident energy. Adsorption rates increase with increasing incident energy until 5 eV is reached. After 5 eV, adsorption rates decrease as incident energy increases. At incident energies greater than 5 eV, adsorption rates increase with the number of graphene layers. At low incident energies (<1 eV), no isotopic effects on interactions are observed since the predominant interaction is derived from the force of π electrons. Between 1 eV and 50 eV, heavier isotopes exhibit higher adsorption rates and lower reflection rates than lighter isotopes, due to the greater momentum of heavier isotopes. Adsorption rates are consistently higher when the incident angle of the impacting atoms is smaller between 0.5 eV and 5 eV. At higher energies (>5 eV), larger incident angles lead to higher reflection and lower penetration rates. At high incident energies (>5 eV), crumpled graphene has higher adsorption and lower penetration rates than wrinkled or unwrinkled graphene. The results obtained in this research study will be used to develop novel nanomaterials that can be employed for tritium control.

• Bulletin of the Korean Mathematical Society
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• v.52 no.5
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• pp.1467-1480
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• 2015

Generalized Fibonacci and Lucas sequences ($U_n$) and ($V_n$) are defined by the recurrence relations $U_{n+1}=PU_n+QU_{n-1}$ and $V_{n+1}=PV_n+QV_{n-1}$, $n{\geq}1$, with initial conditions $U_0=0$, $U_1=1$ and $V_0=2$, $V_1=P$. This paper deals with Fibonacci and Lucas numbers of the form $U_n$(P, Q) and $V_n$(P, Q) with the special consideration that $P{\geq}3$ is odd and Q = -1. Under these consideration, we solve the equations $V_n=5kx^2$, $V_n=7kx^2$, $V_n=5kx^2{\pm}1$, and $V_n=7kx^2{\pm}1$ when $k{\mid}P$ with k > 1. Moreover, we solve the equations $V_n=5x^2{\pm}1$ and $V_n=7x^2{\pm}1$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.2
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• pp.47-54
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• 2020

To develop the bright-vivid red- and yellow-inorganic fluorescent pigments with high luminescence properties, A₃V₅O₁₄ (A = K and Rb) and Cs₂V₄O₁₁ inorganic pigments were synthesized by a water assisted solid state reaction (WASSR) method and a conventional solid state reaction method. Although impurity peaks corresponding to the AVO₃ and AV₃O₈ (A = K, Rb, and Cs) were observed in all samples prepared, the trigonal structure A₃V₅O₁₄ (A = K and Rb) and orthorhombic structure Cs₂V₄O₁₁ were successfully obtained as a main phase. These inorganic pigments showed the broad absorption band (under 550 nm) originated from CT transitions of VO₄ polyhedron, and the strong broad red- and green-emission bands due to ³T₂ → ¹A₁ and ³T₁ → ¹A₁ transitions of the [VO₄]^3- group. The A₃V₅O₁₄ (A = K and Rb) and Cs₂V₄O₁₁ pigments showed a bright-vivid red- and yellow-body color, where the a* values of the A₃V₅O₁₄ (A = K and Rb) were +35.5 and +45.9, respectively, and b* value of Cs₂V₄O₁₁ pigments was +50.3. The L* values of the A₃V₅O₁₄ (A = K and Rb) and Cs₂V₄O₁₁ inorganic pigments were over +45. These results indicate that the A₃V₅O₁₄ (A = K and Rb) and Cs₂V₄O₁₁ inorganic pigments could be an attractive candidate as a bright-vivid red- and yellow inorganic pigments.

• Food Science and Preservation
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• v.17 no.4
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• pp.563-570
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• 2010

We sought to ferment wine from mulberry (Morus alba) juice. The soluble solid content was $9.5{\sim}14.5^{\circ}brix$ on day 6 of fermentation, and gradually fell later; sugar was not further consumed when $3^{\circ}brix$ was attained. Alcohol content rose dramatically on day 6 of fermentation, being 4.5% (v/v) at fermentation temperatures of 16C and 18C, 6.5% (v/v) at 20C, and 8.0% (v/v) at 25C, rising further to 10.5~11.5% (v/v) on day 48, at higher culture temperatures. Citric acid, malic acid, and oxalic acid were present in mulberries. The levels of both citric and oxalic acid fell after fermentation, whereas malic acid concentration increased. All of fructose, glucose, maltose, and sucrose were fermented. Electron-donating ability (EDA) was elevated to over 90% of the control value in mulberry juice diluted to 40% (v/v). SOD-like activities in juice and wine were 80.1% and 72.1% of the control value. Nitrite-scavenging abilities (NSAs) were 86.2% and 85.2% of control in undiluted juice and wine, respectively. Mulberry juice had an activation level higher than that of mulberry wine, but functionality neither rose nor fell after fermentation. Insensory evaluation, the overall wine score was better than average, at 5.00, demonstrating the commercial potential of mulberry wine.

• Journal of the Korean Ceramic Society
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• v.38 no.5
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• pp.438-445
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• 2001

600 W의 마이크로파 출력 하에서 PbO, V$_2$O$_{5}$, TeO$_2$ 및 V$_2$O$_{5}$-PbO-TeO$_2$성분들의 마이크로파 발열 특성을 조사하였다. V$_2$O$_{5}$ 성분의 높은 마이크로파 흡수능에 기인하여 V$_2$O$_{5}$-PbO-TeO$_2$유리상 시편들은 마이크로파를 흡수하여 주어진 온도까지 직접 가열되었다. XRD, OM, SEM 및 고전압 발생 측정기를 통하여 재래식 열 및 마이크로파 공정에서 열처리된 시편들의 결정화 및 전기 전도도의 특성을 비교 조사하였다. PbV$_2$O$_{6}$ 및 Pb$_4$V$_2$O$_{9}$ 결정상들이 마이크로파 열처리된 시편에서는 존재하였다. 그러나, 재래식 열처리된 시편들에서는 존재하지 않는다는 것을 확인하였고, 재래식 열처리된 시편들에 비하여 마이크로파 열처리된 시편들의 전기 전도도 값이 상대적으로 높았다.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.211-216
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• 2010

$(NH_4)_{0.3}V_2O_5$ nanorods and $V_2O_5$ nanosheets have been synthesized by the reaction of $V_2O_5$ gel via homogeneous precipitation process employing urea and formic acid. The electrochemical and chemical characteristics of these nanomaterials have been investigated using TGA, SEM, FT-IR, XRD, and LSV. The interlayer distance of $(NH_4)_{0.3}V_2O_5$ was about $10.7{\AA}$, and that of $V_2O_5$ synthesized by using formic acid was $14.2{\AA}$. The surface morphology of $(NH_4)_{0.3}V_2O_5$ and $V_2O_5$ showed features that looked like nanorods and nanosheets, respectively. Specific capacity of $(NH_4)_{0.3}V_2O_5$ nanorods prepared at $95^{\circ}C$ was at least 280 mAh/g at 10 mA/g discharge rate.