• 한국수산과학회지
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• 제18권5호
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• pp.447-454
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• 1985

양식 잉어의 품질을 지질성분면에서 평가하기 위하여 천연 및 양식 잉어의 지질 조성 및 이들 지질의 구성지방산을 분석${\cdot}$비교하였고, 이스라엘 잉어의 지질성분과도 비교하였다. 또 양식 잉어 및 이스라엘 잉어의 지방산과 사료 지방산을 분석${\cdot}$비교한 결과는 다음과 같다. 1. 총지질 함량은 양식 잉어가 천연 잉어보다는 약간 낮은 반면 이스라엘 잉어와는 거의 비슷하였다. 부위별로는 천연 및 양식 잉어는 내장부가 가식부보다 총지질이 2배 이상 높았으나, 이스라엘 잉어는 가식부와 내장부가 거의 비슷하였다. 2. 천연 및 양식 잉어와 이스라엘 잉어의 지질 조성은 거의 비슷한 경향을 나타내고 있었다. 즉 중성지질이 대부분을 차지하고 당지질과 인지질은 아주 적었다. 또 부위별 지질 조성을 비교해 보면 중성지질의 함량은 천연 잉어의 경우는 내장부가 가식부보다 많은 반면 양식 잉어와 이스라엘 잉어는 그 반대였다. 가식부의 당지질과 인지질 함량은 양식 잉어의 경우는 당지질이 인지질보다 많은 반면 이스라엘 잉어는 인지질이 당지질보다 많았다. 또 중성지질은 TG의 함량이 가장 많았으며 인지질은 PC와 PE가 가장 많았다. 3. 가식부의 중성지질의 중요 구성지방산 함량은 $C_{18:1},\;C_{18:2},\;C_{18:3},\;C_{22:5},\;C_{22:6}$산은 양식 잉어가 천연 잉어보다 높은 반면, $C_{16:0},\;C_{18:0},\;C_{16:1},\;C_{20:4},\;C_{20:5}$산은 천연 잉어가 양식 잉어보다 높았다. 이스라엘잉어의 경우에는 $C_{18:2}$산의 함량이 천연 및 양식 잉어에 비해 상당히 높게 나타났다. 인지질의 경우는 $C_{18:0},\;C_{18:1},\;C_{18:2},\;C_{18:3},\;_C{22:6}$산은 양식산이 천연산보다 많은 반면 $C_{16:0},\;C_{16:1},\;C_{20:4},\;C_{20:5},\;C_{22:5}$산은 천연산이 양식산보다 높았다. 4. 중성지질의 불포화도(TUFA/TSFA)는 양식산이 천연산보다 약간 높았으며, 또 이스라엘 잉어는 양식 잉어보다도 약간 더 높았다. 인지질의 경우도 이스라엘 잉어>양식 잉어>천연 잉어의 순이었다. 필수지방산 함량(TEFA)은 중성지질의 경우 가식부는 양식 잉어가 천연 잉어보다 높은 반면 내장부는 천연 잉어가 양식 잉어보다 높았다. 인지질의 경우는 가식부에서 이스라엘 잉어가 천연 및 양식 잉어보다 약간 더 높고, 또 천연 잉어가 양식 잉어보다 높았다. 5. w3고도불포화지방산 함량 (w3 HUFA)은 중성지질의 경우는 필수지방산 함량의 경향과 거의 비슷하였고 인지질의 경우는 이스라엘 잉어가 가장 높고, 양식 잉어, 천연 잉어의 순이었다. 6. 사료 지방산(C)에 대한 양식 잉어의 지방산(A)의 비(A/C) 및 이스라엘 잉어의 지방산(B)의 비(B/C)를 비교하여 보면 양식 잉어는 $C_{20:5}\;w3(0.12),\;C_{22:5}\;w6(0.53),\;C_{22:5}\;w3(0.68),\;C_{22:6}\;w3(0.26)$산이 아주 낮았고, 이스라엘 잉어는 $C_{18:3}\;w3(0.61),\;C_{20:5}\;w3(0.11),\;C_{22:4}\;w6(0.16),\;C_{22:5}\;w6(0.07),\;C_{22:6}\;w3(1.53)$산이 아주 낮게 나타났다. 따라서 주로 이들 w3고도불포화지방산들이 polyene산의 생합성 및 성장률에 깊이 관계할 가능성이 있다고 판단되었다.

• 센서학회지
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• 제18권3호
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• pp.222-225
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• 2009

This paper describes the fabrication and characteristics of Schottky micro hydrogen sensors for high temperatures by using polycrystalline(poly) 3C-SiC thin films grown on Si substrates with thermal oxide layer using APCVD. Pd/poly 3C-SiC Schottky diodes were made and evaluated by I-V and C-V measurements. Electric current density and barrier height voltage were $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices could operate stably at about 400 $^{\circ}$. The characteristics of implemented sensors have been investigated in terms of sensitivity, linearity of response, response rate, and response time. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature $H_2$ sensor applications.

• 한국대기환경학회지
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• 제13권1호
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• pp.91-98
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• 1997

Y-zeolite and ${\gamma}$-Al$_2$O$_3$ were used as supports on CO and $C_3$H$_{6}$ oxidation for diesel emission control. The catalysts composed of Pd and Pt as active components were wash coated on honeycomb type ceramic substrate. The oxidation of CO and $C_3$H$_{6}$ was carried out over prepared honeycomb in a fixed bed continuous reactor in the temperature range of 20$0^{\circ}C$~50$0^{\circ}C$ and 20,000 GHSV (h$^{-1}$ ). Surface area of Y-zeolite was larger than that of ${\gamma}$-Al$_2$O$_3$ due to channel structure of Y-zeolite. Therefore, high conversion of CO and $C_3$H$_{6}$ could be obtained because of good dispersion of active metals over Y-zeolite. The honeycomb used Y-zeolite as a support showed higher $C_3$H$_{6}$ conversion than that of ${\gamma}$-Al$_2$O$_3$ due to better cracking and isomerization activity of Y-zeolite. PdPt catalyst showed high conversion of CO and $C_3$H$_{6}$ at low temperature region, 20$0^{\circ}C$~30$0^{\circ}C$, for their synergy effects. PdPt/Y-Zeolite catalyst could achieve more than 80％ conversion of $C_3$H$_{6}$ at 30$0^{\circ}C$. The use of Y-zeolite as a support increased CO and $C_3$H$_{6}$ conversion, and decreased SO$_2$ conversion very effectively. Y-zeolite found to have a good adaptability as a support for the diesel emission after treatment system.

• 한국세라믹학회지
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• 제21권2호
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• pp.143-148
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• 1984

In this study we mainly dealt with the effects of organic retarder(calcium lignosulfate) on the early hydration process of clinker minerals. From a consideration of the hydration process of tricalcium silicate $(C_3S)$ tricalcium silicate $(C_3S)$-tricalcium aluminate $(C_3A)$ tricalcium silicate $(C_3S)$-tetracalcium aluminof-errite $(C_4AF)$ systems with calcium lignosulfate the following results were obtained. 1. when 0.25wt% of CLS was added to $C_3S$ the hydration process was progressed normally but adding of 0.5wt% its hydration was greatly retarded. 2. The hydration of $C_3S$-$C_3A$ system was progressed normally up to 0.5wt% but by adding gypsum its hydration was retarded slightly. 3. The hydration of $C_3S$-$C_4AF$ system was greatly retarded even with 0.25wt% of CLS but by adding gypsum its hydration process was recovered normally.

• 한국세라믹학회지
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• 제27권2호
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• pp.195-200
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• 1990

For the development of low energy cement, the belite cement clinker of calcium sulphoaluminate ferrite type was synthesized at 130$0^{\circ}C$ and containing C2S, C4A3S as the major minerals along with C3A, C4AF, CS by using limestone, dolomite, clay, iron ore, gypsum and alumina as raw materials. At over 130$0^{\circ}C$, C4A3S was decomposed and thus C3A was increased. When hydrated, this cement was hardened, producing ettringite, CSH, etc.

• 한국세라믹학회지
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• 제29권11호
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• pp.837-842
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• 1992

SiC and Si mixtures dispersed by 0.5~10.0 wt% of Al2O3 and reinforced by SiC whisker were sintered to Si3N4 bonded SiC bodies at 140$0^{\circ}C$ in a N2 gas atmosphere, and the nitridation and mechanical properties of sintered bodies were investigated. From these observation, it is concluded that relative density and bending strength increased with the rising of nitridation and the highest nitridation ratio was obtained for a specimen having 1.5 wt% Al2O3. On the other hand, the amount of $\beta$-Si3N4 in the specimens containing Al2O3 more than 5.0 wt% was increased abruptly and the best in fracture toughness was sintered for a composits having 30 wt% SiC whiskers.

• 한국세라믹학회지
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• 제33권10호
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• pp.1163-1169
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• 1996

The effects of borax on the phase formation of C2S, C4A3 and $\alpha$'-C2S phases. It has negative effects on formation of C4A3 And it lowers the forming temperature of C4AF. It also has been found that borax improves the clinkerization of MBC. In the MBC clinker with borax 3% C2S have larger and more irregular shapes, larger C/S mole ratio and C4A3 have smaller size larger C/ molr ratio than in the clinker without borax.

• 한국전기전자재료학회논문지
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• 제23권2호
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• pp.98-102
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• 2010

This paper describes that single crystalline 3C-SiC (cubic silicon carbide) thin films have been deposited on carbonized Si(100) substrates using hexamethyldisilane (HMDS, $Si_2(CH_3){_6}$) as a safe organosilane single precursor and a nonflammable mixture of Ar and $H_2$ gas as the carrier gas by APCVD at $1280^{\circ}C$. The deposition was performed under various conditions to determine the optimized growth condition. The crystallinity of the 3C-SiC thin film was analyzed by XRD (X-ray diffraction). The surface morphology was also observed by AFM (atomic force microscopy) and voids between SiC and Si interfaces were measured by SEM (scanning electron microscopy). Finally, residual strain and hall mobility was investigated by surface profiler and hall measurement, respectively. From these results, the single crystalline 3C-SiC film had a good crystal quality without defects due to viods, a low residual stress, a very low roughness.

• Transactions on Electrical and Electronic Materials
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• 제10권4호
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• pp.131-134
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• 2009

The electrical properties and the microstructure of nitrogen-doped poly 3C-SiC films used for micro thermal sensors were studied according to different thicknesses. Poly 3C-SiC films were deposited by LPCVD (low pressure chemical vapor deposition) at $900^{\circ}C$ with a pressure of 4 torr using $SiH_2Cl_2$ (100%, 35 sccm) and $C_2H_2$ (5% in $H_2$, 180 sccm) as the Si and C precursors, and $NH_3$ (5% in $H_2$, 64 sccm) as the dopant source gas. The resistivity of the poly SiC films with a 1,530 ${\AA}$ thickness was 32.7 ${\Omega}-cm$ and decreased to 0.0129 ${\Omega}-cm$ at 16,963 ${\AA}$. The measurement of the resistance variations at different thicknesses were carried out within the $25^{\circ}C$ to $350^{\circ}C$ temperature range. While the size of the resistance variation decreased when the films thickness increased, the linearity of the resistance variation improved. Micro heaters and RTD sensors were fabricated on a $Si_3N_4$ membrane by using poly 3C-SiC with a 1um thickness using a surface MEMS process. The heating temperature of the SiC micro heater, fabricated on 250 ${\mu}m$${\times}$250 ${\mu}m$ $Si_3N_4$ membrane was $410^{\circ}C$ at an 80 mW input power. These 3C-SiC heaters and RTD sensors, fabricated by surface MEMS, have a low power consumption and deliver a good long term stability for the various thermal sensors requiring thermal stability.

• 한국결정학회지
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• 제1권1호
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• pp.14-18
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• 1990

Econazole nitrate, 1-{2-[(4-chlorophenyl)methoxy]-2-(2,4-dichlorophenyl) ethy1}-1H-imidazole mono-nitrate, C18 H16 CI13 N3 O4의 단위세포 상수는 a=19.337(4) A, b=15.191(5) A c=7.601(3)A, β=91.72(2)μ V=2000.0A3 Do=1.49g/ml Dm=1.47g/ml, M=4.31cm-1 F(000)=912.0, 2T=298K,공간군은 P2₁/C이고 단사 정계이며 Z=4이다. λ=(Mo-Ka)=0.7107 A을 사용한 1330개의 Intensity data에 대해 최종 R값은 0.06이다. Econazole nitrate의 각 세 ring은 각각 평면이며 B,A,C ring순서로 층계를 이루고 있다. 반면에 Econazole의 A와 C ring은 거의 같은 평면에 누워 있으나 B ring 은 거의 같은 평면이며 B,A,C ring순서로 층계를 이루고 있다.반면에 Econazole의 A와 C ring은 거의 같은 평면에 누워있으나 B ring과는 약 60˚의 평면각을 이루고 있다. Nitrate의 O(*3)와 Imidaze의 N(2) 사이의 수소결합은 Econazole slt의 안정화에 기여한다.