• 한국세라믹학회지
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• 제55권5호
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• pp.473-479
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• 2018

Highly toxic gases such as hydrogen sulfide ($H_2S$), carbon dioxide ($CO_2$), and ammonia ($NH_3$) are generated by both nature and human activities and affect human health. In this research, activated carbon combined with $Ca(OH)_2$ and $CaCO_3$ (AC-CO and AC-CC, respectively) were fabricated and applied in absorbing toxic gases from air pollutants. Activated charcoal powder was compressed in the form of pellets and used in the designated conditions. The optimum operating conditions and material properties, such as adsorption capacity, effect of weight ratio of the mixture, and hardness, have been investigated after combining with the calcium derivative. The good performance exhibited in this study suggests that this material is expected to be an effective and economically viable adsorbent for $NH_3$, $CO_2$, and $H_2S$ removal from the air system.

• 마이크로전자및패키징학회지
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• 제19권3호
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• pp.43-48
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• 2012

마이크로파 유전체의 비유전율 측정에 널리 사용되고 있는 post resonator 기법에서 시편의 형상과 기구물의 편차 등에 의해서 발생하는 비유전율 계산의 오차요인에 대해 시뮬레이션과 시편 실측을 통해 분석하였다. HFSS 시뮬레이션을 통하여 post resonator 측정 기구물에 놓여진 유전체(유전율 38) 디스크의 $S_{21}$ 파라메터 스펙트럼을 계산하고 $TE_{011}$ 모드 공진주파수로부터 비유전율을 계산하였다. 시편의 형상비(직경D/높이H)가 0.8~1.6 사이로 변화함에 따라 계산되는 비유전율 값의 오차는 약 0.3% 이내로 미미하였다. 시편과 상하부 도체 사이에 1~10% 정도의 공극이 존재할 경우, 비유 전율은 1~10% 정도의 높은 수준으로 오차가 발생하였다. 시편이 중심부에서 벗어나서 위치하는 것은 비유전율 측정에 오차를 유발하지 않았다. 이러한 시뮬레이션 결과는 제작 샘플의 실제 측정을 통해 유사한 경향성을 확인하였다.

• 동아시아식생활학회지
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• 제1권1호
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• pp.99-111
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• 1991

In each nuruk using today, effect of pH on glucoamylase activity and viable cell count of yeast and bacteria was measured. Common components during fermentation, alcohol, acetaldehyde and acetone, amino acid composition, and total sugars and mineral content were determined in yakju(korean wine) brewed from different ingredients and by different methods. Results are summarized as follows ; 1. The lower the pH, the lower the glucoamylase activity in JK, BK, JK-S BK-S and JN. But the higher the glucoamylase activity ratio in Koji and KN. 2. Yeast and bacteria cell count could not determined in nuruk inoculated of seed. In JK, BK and JN, yeast cell count was 50${\times}$104∼80${\times}$104, bacteria cell count was 5${\times}$106∼24${\times}$106. 3. In yakju during fermentation, pH was higher in RU, total acidity content was higher in ST-N, ST-K, RU and ST-RUPO and alcohol content was lower in RUPO and ST-RUPO. 4. Ethanol and acetaldehyde content were highest in dukyunju. Trace amount of acetone was determined only in ST-K, RUPO and ST-RUPO . n-Propyl alcohol content was higher in ST-K, ST-RUPO and ST-N, iso-butyl alcohol content was higher in L-RUPO, Dukyunju and Songyupju and iso-amyl alcohol content was higher in Songyupju, RU, L-RUPO and Dukyunju. 5. In amino acids composition of each yakju, Pro, Ala and Val content was higher than other amino acids. Total amino acids content was the highest in Dukyunju and second highest in ST-N, NH3 was higher in ST-N, Dukyunju, RUPO than other samples. 6. Total sugars content was the highest in ST-N and second highest in RU. 7. P, K and Mg content were higher in Dukyunju and ST-N than in other samples. In Dukyunju, Ca and P ratio was 0.075 because of low Ca content and high P content.

• 한국광물학회지
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• 제17권1호
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• pp.11-21
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• 2004

자발적 침전법에 의하여 다양한 과포화 용액에서 탄산염광물을 합성하였다. 합성용액의 온도는 $25^{\circ}C$에서 유지 시켰고 pH범위는 6.9에서 8.8 이였다. 용액의 과포화도 조절 시 2가지 변수를 두어 농도를 변화 시켰다. (1) total carbonate의 농도와 total calcium의 농도비가 다음 세 가지 조건을 만족시키도록 변화시켰다: [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$ >1. [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$=1, and [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$<1. (2) 앞서 언급한 조건에 total calcium의 농도를 0.02 mol/d $m^3$, 0.2 mol/d $m^3$, 그리고 0.4 mo1/d $m^3$이 되도록 변화 시켰다. [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$$\geq$ 1의 조건 하에서 형성된 미립의 탄산염 광물은 대부분 거의 순수한 방해석으로 바테라이트가 1% 이하로 존재하였으며 이와는 달리 [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$ < 1 조건하에서는 거의 순수한 바테라이트가 합성되었다. 본 연구 결과 탄산염광물의 상은 합성 용액상의 [C $O_3$]$_{Τ}$ 농도보다는 [C $O_3$]$_{Τ}$의 농도에 의하여 좌우되는 것으로 나타났다. 또한 바테라이트의 합성 결과는 [C $O_3$]$_{Τ}$/[Ca]$_{Τ}$의 비가 0.8 에서 0.5로 낮아짐에 따라 roughness가 증가하고 결과적으로 광물표면적이 5.64∼7.34 $\mu\textrm{m}$에서 8.39∼10.3 $\mu\textrm{m}$로 증가한다.

• 한국농공학회논문집
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• 제53권6호
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• pp.59-65
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• 2011

This study was performed to evaluate the compressive and flexural strength, void ratio and permeability coefficient used powdered waste glass, $CaCO_3$, recycled coarse aggregate and unsaturated polyester resin to find optimum mix design of permeable polymer concrete for pavement. The compressive and flexural strength of permeable polymer concrete for pavement using powdered waste glass were in the range of 16.8~19.7 MPa and 4.7~6.1 MPa, respectively. it was satisfied the regulation of permeable concrete for pavement (18 MPa and 4.5 MPa). The void ratio and permeability coefficient were decreased with increasing the powdered waste glass, respectively. The void ratio and permeability coefficient were satisfied national regulation of permeable concrete for pavement (8 % and $1{\times}10^{-2}$ cm/s). In addition, this study found out that required amount of binder was decreased with increasing the powdered waste glass. This fact is expected to have economical effects during the use of powdered waste glass in the manufacture of permeable polymer concrete for pavement. Accodingly, the powdered waste glass can be used for permeable concrete material.

• 한국식품영양과학회지
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• 제30권3호
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• pp.455-459
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• 2001

Tofu (soybean curd) was made with whole soybean flour (WSF, 420 mesh) by various processing conditions of water addition ratio, heating time, coagulation temperature, molding pressure and 0.3% of mixed coagulant (CaSO₄:GDL=50:50(w/w)). Yield content of WSF-tofu was the highest in processing condition of 85℃ coagulation temperature, 10 times water addition, 5min. heating time and 25.00 g/㎠ molding pressure. As the increase of the water addition ratio from 8 to 14 times (water:WSF, v/w), Hunter's L and a values were increased. Raising of heating time (100℃, 1, 5, 10 and 15 min), a and b value were increased. Textural properties of WSF-tofu were significantly affected by coagulation temperature (75, 80, 85 and 90℃). Hardness was increased, but adhesiveness and cohesiveness were decreased. heating time was influenced on harness of WSF-tofu, but water addition ratio was not affected on hardness of WSF-tofu. Increasing of molding pressure (16.83, 25.00, 33.22 and 41.67 g/㎠, 1 hr) was resulted from a increased hardness, gumminess and chewingss of tofu, but adhesiveness was addition ratio, 5 min heating time and 25.00 g/㎠ molding pressure recorded the highest score in sensory evaluation test.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.363-370
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• 1992

토양으로부터 PHB 생산능이 우수한 균주 FL-027을 분리하여 분류학적 제 특성을 검토한 결과 Alcaligenes속으로 동정되었다. Alcaligenes sp.의 최적 생육 조건은 과당 8.0$g/\ell$, $(NH_4)_2S0_4$ 3.0$g/\ell$ (즉 C/N molar ratio가 5.04) 및 pH7.0과 $30^{\circ}C$였으며, PHB 축적은 과당 8.0$g/\ell$, (NH4)2SO4 0.25g/l(즉 C/N molar ratio가 60) 및 pH6.5와 30'C에서 가장 양호하였다. $NH_4^+$, $Ca^{2+}$, $SO_4^{2+}$의 결핍이 PHB축적을 촉진하였으나 이들 중 $NH_4^+$가 가장 효과적으로 PHB축적을 유도하였다. 고농도배양을 위해 과당을 간헐적으로 첨가하여 최적농도를 유지하면서 유가배양을 실시한 결과 균체량은 25.1$g/\ell$, PHB 축적량은 10.84$g/\ell$로 건조균체량의 43까지 축적되었다. 분리정제된 PHB를 IR 및 $^1H-NMR$로 분석한결과 3-hydroxybutyric acid의 homopolymer임을 알 수 있었다.

• 한국식품영양과학회지
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• 제27권2호
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• pp.220-226
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• 1998

This study was undertaken to analyze proximate comosition, mineral contents and fatty acid composition of pure jemsosojoo(PJ) and jemsosojoo added medicinal herb(JMH). Mositure, ash, crude protein and crude fat of pure jemsosojoo were higher than those of the JMH, but carbohydrate content was higher in the JMH. Among minerals, Ca, Mg, Fe, Zn content of the JMH were higher than those of the PJ, while P and Na were higher in the PJ and those difference were significant between the PJ and the JMH(p<0.05). U/S (unsaturaed fatty acid/saturated fatty acid) ratio was higher in the JMH than those of the PJ, the ratio o fglycolipid was 1.75 in the PJ and that of neutral lipid was 3.07 in the JMH. Octadecenoic acid, hexadecanoic acid, octadecenoic acid and hexadecenoic acid were major fatty acids in the total lipids, neutral lipids glycolipids and phospolipids of the PJ and the JMH. Especially, octadecadienoic acid and octadecatrienoic acid were higher in the JMH than those of the PJ.

• 한국식품영양과학회지
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• 제4권1호
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• pp.19-23
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• 1975

From a study of the nutrient and gelation substances in Korean persimmon such as Jangdongsi, Pasi, Teabongsi, Kurigam, Nabjackgam, Gamsi and Hucks: The results obtained are summerized as follows: 1. According as persimmon changes into mellowed persimmon in the same kind the ammounts of sugar was increased, while the ammounts of fiber was decreased, but there was little difference in the other nutrient contents. 2. The ratio of 'Ca' and 'P' in persimmons in generally balanced at 1 : 2.5 3. Compared to the standard combination ratio of gelation substance, pectin in the persimmons was over but acid and sugars were very low.

• 대한환경공학회지
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• 제30권4호
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• pp.385-392
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• 2008

본 연구에서는 해수침투를 방지하기 위해 실험실에서 제조한 하수 방류수를 이용하였으며, 각각의 함양 및 양수 조건에 따른 해수침투 진행 과정을 지표미생물인 Escherichia coli와 Enterococcus faecalis를 이용하여 평가하였다. 해수침투의 대표적인 화학적 지표인자인 Cl$^-$와 Ca$^{2+}$, Mg$^{2+}$ 및 비전도도값 등은 해수에 의해 인공 대수층내의 지질매체와 양이온간의 이온 교환이 발생되는 수조 내에서 동시에 분석되었다. 지표 생물로 이용된 Escherichia coli와 Enterococcus faecalis 모두 해수침투에 따라 증가하는 염분 농도에 민감하게 반응하였으며, Enterococcus faecalis의 경우 Escherichia coli 보다 염분 농도에 더 큰 저항을 보였다. 시간에 따른 Enterococcus faecalis / Escherichia coli 값은 함양과 양수가 10 mL/min으로 동일할 경우에는 E. coli 초기 주입 농도가 90% 이상의 사멸을 보이는 18시간 이후에 50$\sim$100배 이상으로 증가하였다. 그러나 함양과 양수가 5 mL/min의 경우에는 E. coli의 완만한 사멸율로 인해 운전 시간 내내 2.5$\sim$5.0 사이의 일정한 비를 유지하였다. 또한 본 연구에서 분석된 염소 이온과 비전도도, Ca$^{2+}$ 및 Mg$^{2+}$농도는 서로간에 0.9 이상의 높은 상관관계를 나타내었으며, 인공 해수가 인공 대수층내로 침투되면서 일어나는 양이온 교환 반응의 진행 여부는 음의 $\Delta$Na, $\Delta$Mg값과 양의 $\Delta$Ca의 관측을 통해 효과적으로 확인할 수 있었다.