• Electrical & Electronic Materials
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• v.9 no.6
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• pp.605-615
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• 1996

In this paper, the effect of alkaline oxide addition such as Li$_{2}$O and Na$_{2}$O on the microstructure and humidity sensitivity of V$_{2}$O$_{5}$(2 mol%)-doped TiO$_{2}$(98 mol%) was investigated as a function of amount (0, 1, 2, 5, 10 mol%) of Li$_{2}$O and Na$_{2}$O additives. The pores in the alkaline free sample were distributed mostly in the range between 0.16 and 1.0.mu.m in diameter and its porosity was 23.29%. Li$_{2}$O caused grain overgrowth and reduced the porosity with a narrow distribution of the pore size, leading to poor humidity sensitivity. Na$_{2}$O helped to enlarge the distribution of the pore size through the formation of small soluble phases. The pore sizes of the sample containing Na$_{2}$O 2mol% were distributed mostly in the range between 1.0 and 2.5.mu.m in diameter and its porosity and intrusion volume of mercury were 31.13 % and 0.1155 mL/g respectively, which consequently improved the humidity sensing characteristics such as the sensitivity and temperature-stability. Especially, the addition of 2mol% of Na$_{2}$O improved the humidity-sensing characteristics such as sensitivity and linearity in the whole range between 30 and 90 %RH (Percentage Relative Humidity)y)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.898-901
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• 2004

[ $ZnCr_2O_4$ ]를 모물질로 하고 MgO, $TiO_2$를 몰비로 2:1, 4:1, 6:1, 및 8:1이 되게 정량적으로 조합한 후, 조사하였다. $ZnCr_2O_4$-MgO와 $ZnCr_2O_4-TiO_2$를 X-선 분석한 결과 Spinel 결정구조를 형성하였으며, 또한 SEM과 EDX 분석결과 각각 $Li_2CrO_4$와 $Li_3VO_4$의 형성으로 인하여 저항 특성이 나타나는 것을 알 수 있었다. $ZnCr_2O_4-MgO$, $ZnCr_2O_4-TiO_2$에서 MgO의 양이 증가할수록 저항값은 약간 감소하는 반면, $TiO_2$의 양이 증가할수록 저항값이 급격히 증가하는 특성을 나타내었고, 감습 특성에서도 M??보다 TiO2가 더 높게 나타내었다. 습에 따른 복원 특성의 경우 $700^{\circ}C$에서 소결한 ($ZnCr_2O_4:MgO=4:1$)과 ($ZnCr_2O_4:TiO_2=6:1$) 조성의 센서가 가장 양호하였다.

• Polymer(Korea)
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• v.33 no.1
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• pp.19-25
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• 2009

New polyelectrolytes derived from ionene-containing photocurable reactive oligomer (PIDM) were prepared for water-resistant humidity-sensitive membranes. The mixture of PIDM, hexamethylene dimethacrylate (HDM), pentaerythritol triacrylate dimer (SP1013), and photoinitiator was simultaneously coated on the sensor electrode with photoinitiated radical polymerization. The pretreatment of the substrates with vinyl-type silane-coupling reagent was performed for improving the water durability and stability of the sensors at high temperature and humidity. When the resistance dependences on the relative humidity of the crosslinked PIDMs were measured, it was found that the resistance varied three orders of magnitude between 20 and 90%RH, which was required for the humidity sensor operating at ambient humidity. Their hysteresis, temperature dependence, response time, water durability, and high temperature/humidity stabilities were measured and evaluated as a humidity-sensing membrane.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1066-1068
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• 1995

The formation properties and oxidation mechanism of electrochemically oxidized porous silicon(OPS) films have been studied. To examine the humidity-sensitive properties of OPS films, surface-type and bulk-type humidity sensors were fabricated. The oxidized thickness of porous silicon layer(PSL) increases with the charge supplied during electrochemical oxidation and current density. The humidity sensor shows high sensitivity at high relative humidity in low temperature. The sensitivity and linearity can be improved by increasing a porosity of PSL.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.2
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• pp.95-97
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• 2013

$CaTiO_3$ thin films using silk screen printing technology were fabricated and their humidity sensitive characteristics have been investigated. The specimens were sintered at $1000^{\circ}C$, $1050^{\circ}C$, $1100^{\circ}C$ for 1 hour and the best humidity sensitivity was shown in the specimens sintered at $1000^{\circ}C$. The humidity sensitivity decreased with increasing measuring frequencies and was stable at different abient temperatures. Hysteresis of impedance variation with increasing and decreasing relative humidity were negligible.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.737-739
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• 1992

The microstructure and humidity sensitive characteristics of $V_2O_5$ doped $CaTiO_3$ were studied. Sensing elements were prepared in bulk form. This element exhibits a porous structure. The grain grows and electrical conductivity increases as doping amount of $V_2O_5$ increases. The change of impedance and capacitance under different r.h is remarkable, and the conduction carriers of this element were ions.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.161-163
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• 2008

$TiO_2-V_2O_5$ sol was fabricated using sol-gel method and $TiO_2-V_2O_5$, thin films were fabricated using dip-coating method. $V_2O_5$ sol was added 0.01mole, 0.03mole, 0.05mole into $TiO_2$ sol. Capacitance of thin films decreased with increasing $V_2O_5$ additive and it increased largest at 0.01mole. Because adsorption time and desorption time of thin films was about 2 minutes 40 seconds and about 3 minutes 40 seconds respectively, adsorption time was faster about 1 minutes than desorption time.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.1-12
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• 2006

통과분석(通過分析) ${\ulcorner}$금궤요약심전${\lrcorner}$ 습병조문중우재경적주석(濕病條文中尤在涇的注釋), 득출여하결론(得出如下結論). 습사감인(濕邪感人), 시우태양이류인관절(始于太陽而流人關節), 평일사덕불급지인(平日士德不及之人), 역감습사(易感濕邪), 습병(濕病), 무한부작(無寒不作), 여경병비풍불성(如涇病非風不成), 습병지표증시신번동(濕病之表證是身煩疼), 관절동번(關節疼煩); 이증시소변불리(裏證是小便不利), 대변반쾌(大便反快), 습황유우습사외성이기양내울발생(濕黃由于濕邪外盛而其陽內鬱發生). 표증오하발생적홰, 포만(胞滿), 소변불리등증원인시양기내울(小便不利等證原因是陽氣內鬱). 발열(發熱), 일포소극(日哺所劇), 불시여폐양명유관(不是與肺陽明有關), 이시여풍유휴작유관련(而是與風有休作有關聯). 치료외습증적발한법시징징발한(治療外習證的發汗法是徵徵發汗), 불시과도발한(不是過度發汗), 여과발한과도(如果發汗過度), 근거풍사이습사상존(僅去風邪而濕邪尙存). 약풍습재표(若風濕在表), 가이용마황가출탕(可以用痲黃加朮湯), 마황행인의이감초탕이발한(痲黃杏仁薏苡甘草湯以發汗), 약이한출이표허(若已汗出而表虛), 가이용방기황기탕이실표행습, 약표허무열(若表虛無熱), 불가발탕(不可發湯), 소이용계지부자탕이온경산습(所以用桂枝附子湯以溫經散濕), 혹용백출부자탕이보탕행습(或用白朮附子湯以補湯行濕), 약표이지탕구허(若表裏之湯俱虛), 가이용감초부자탕이포중겸발산(可以用甘草附子湯以補中兼發散).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.328-331
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• 1995

TiO$_2$thin films for humidity sensors have been deposited by RF magnetron sputter and hygroscopic characteristics were investigated. Grain diameter of thin films were increased and hygroscopic characteristics were good as discharge power. Hygroscopic characteristics of thin films heated for 15 min at 500$^{\circ}C$ were better and more linear than that at 400$^{\circ}C$ and were unchanged as Ar flow rate.

• Journal of the Korean Ceramic Society
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• v.37 no.6
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• pp.537-544
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• 2000

Thin-film humidity sensor which TiO2, ZrO2, or CeO2 was added to MgCr2O4-based materials, respectively, were fabricated on the alumina substrate by using a resistant-heating evaporator. Thin films were approximately 2${\mu}{\textrm}{m}$ in grain size and shwoed porous microstructures. The resistance of the sensor decreased with increasing the relative humidity and the MgCr2O4-TiO2 sensor had the best humidity-sensing characteristics (linearity in relative humidity versus resistance).