• Korean Chemical Engineering Research
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• 제57권1호
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• pp.78-84
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• 2019

최근 지속 가능형 에너지로 바이오 부탄올(bio-butanol)에 관한 연구가 활발히 진행되고 있으나, 이의 상업화에는 저렴한 바이오메스 개발 및 경제적 분리 방법 등 선결해야 할 문제들이 있다. 전통적인 ABE 바이오부탄올 발효공정은 아세톤, 부탄올, 에탄올과 함께 유기산(organic acid)과 같은 부산물을 생성한다. 따라서 이들의 상호분리를 위해 아세톤, 부탄올, 에탄올 및 아세틱 산에 대한 상평형 데이터 등은 많이 발표되었으나, 탄소수가 큰 유기산에 대한 상평형 및 혼합물성 데이터는 매우 부족한 실정이다. 따라서 본 연구는 $C_3-C_6$ 유기산 조합의 이성분계 혼합물에 대한 고-액 상평형과 혼합물성으로 과잉부피($V^E$), 굴절율 편차(${\Delta}R$) 그리고 점도 편차(${\Delta}v$)를 298.15 K에서 실험적으로 측정하였다. 측정된 고-액 상평형 데이터는 NRTL, UNIQUAC식을 이용하여 상관시켰으며 RMSD, 0.5 K이하로 잘 상관되었다. 또한 동일 이성분계 혼합물에 대한 $V^E$, ${\Delta}R$ 및 ${\Delta}v$의 혼합물성 데이터는 Redlich-Kister 다항식을 이용해 매개변수를 상관하였으며 약 0.004 이하의 표준편차로 잘 상관됨을 확인하였다.

• 한국지역사회생활과학회지
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• 제21권4호
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• pp.481-488
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• 2010

The objective of this study was the development of the preparation method of fermented turnip juice. The yields and soluble solids of fermented turnip juice were 41.2, 52.8, 56.4 and 57.4%, and 34.3, 42.4, 48.6 and 54.7 $^{\circ}Brix$ with 40, 60, 80 and 100% addition rate of turnip quantity, respectively. The major organic acids in turnip juice were succinic acid, isobutyric acid and fumaric acid, and these organic acids were decreased after fermentation. On the other hand, lactic acid, formic acid, acetic acid, propionic acid and butyric acid were produced during the fermentation. Soluble solid and pH value in fermented turnip decreased by time-dependently. Free radical scavenging activity was increased by fermentation of turnips and nitrate scavenging effects were the highest in pH 3 and increased with adding Omija or Japanese apricot. The best preparation method of fermented turnip juice was fermentation at $24^{\circ}C$ 12-15 days after adding 40% of sucrose to total quantity. As adding Omija, organic acid contents were increased and sensory evaluation was improved in fermented turnip juice.

• 한국가금학회지
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• 제29권2호
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• pp.109-116
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• 2002

유기산제와 효모 배양물의 급여가 산란계의 생산성 및 계란 품질에 미치는 영향을 구명하고자 19주령 이사브라운 갈색계를 이용하여 16주간 사양실험을 시행하였다. 처리구는 무침가구인 대조구, 유기산제와 효모 배양물을 각각 0.1, 0.2% 수준으로 하였고 처리구당 5반복으로 반복당 18수씩 총 450수를 체중이 비슷하게 하여 완전 임의배치하였다. 산란율과 난중, 사료섭취 량은 4주 단위로 측정하였으며, 계란의 난각 강도. 난각 두게, Haugh unit, 난황색을 처리구별로 측정하였다. 난황의 지방산 조성은 실험 개시 후 8주 간격으로 측정하였다. 본 실험의 결과, 효모 배양물 0.1%급여시 31∼34주령의 산란율은 97.1%로 대조구에 비하여 증가하였다(P<0.05). 23∼26주령에서 1일 산란량은 유기산제 0.2% 급여구가 증가하였고(P<0.05), 31∼34주령에서는 효모 배양물 0.1% 급여구가 대조구에 비하여 현저하게 증가하였다(P<0.05). 사료섭취량은 유기산제와 효모 배양물이 대조구와는 타이가 없었지만 27∼30주령에서 효모 배양물 0.1% 급여구는 유기산제 0.1% 급여구 보다 증가하였다(P<0.05). 난각 강도는 34주령에서 유기산제 0.1% 급여구가 효모배양물 0.1% 급여구에 비해서 증가하였으나(P<0.05), 대조구와 차이는 없었다. 34주령에 측정한 Haugh unit은 유기산제 급여구가 대조구보단 현저하게 높았으며(P<0.05), 난황색은 처리구간에 유의적인 차이는 없었다. 유기산제 0.1%급여구는 난황내 C20:4의 함량을 대조구에 비하여 증가시켰고(27주령)(P<0.05), 유기산제 0.1%, 0.2%급여구는 Cl6:0의 함량을 현저하게 감소시켰다 (34주령)(P<0.05).

• 한국초지조사료학회지
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• 제7권3호
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• pp.157-161
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• 1987

In order to utilize the tuber of Jerusalem artichoke (Jerusalem tuberosus L.) which has been considered one of the most economical resources for bioenergy, the tubers of the plant were processed into silage in 11 lab-silo with three levels of mixture of concentrates i.e. 10, 20, 30%. The silage was stored for 20 to 40 days before analyses. The quality of silage was compared with those of the tube-only silage without concentrates. Aproximate composition, pH, ammonium nitrogen, total nitrogen, and organic acids were analyzed. The results obtained are summarized ; 1. With the mixture of concentrates, the water content of the silage was able to be adjusted to 70 percent and NDF significantly increased (P<0.05) while ADF significantly decreased. 2. The content of water-soluble carbohydrate (WSC) was significantly decreased in silages of the mixture of concentrate and the tuber (P<0.05), while total nitrogen and ammonium nitrogen increased. 3. Tube-only silage gave satisfaction in fermentation, particularly organic-acid fermentation. As the storage period extended, Flieg's score of the silage was improved. Conclusively, the tuber of Jerusalem artichoke found to satisfy the requirements of good silage and to be recommended as a good resource for all-inane silage provided the tuber was ensilaged with 20 to 30 percent concentrate.

• 자원리싸이클링
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• 제30권2호
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• pp.53-60
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• 2021

폐리튬이온배터리에 함유된 코발트, 니켈 및 구리를 회수하기 위한 공정 개발의 일환으로 단일금속과 금속혼합물의 침출을 조사했다. 이를 위해 산화제를 첨가하지 않은 무기산과 유기산을 침출제로 사용했다. 본 논문의 실험조건에서 산화제가 없는 무기산과 유기산에서 구리는 전혀 침출되지 않았다. 염산과 황산용액에서 산의 농도, 반응온도, 반응시간 및 광액농도를 변화시켜 단일 금속를 모두 용해시킬 수 있는 조건을 구했다. 또한 염산과 황산용액에서 금속혼합물로부터 니켈과 코발트를 99% 이상 침출시킬 수 있는 조건을 조사했다. 메탄술폰산으로 코발트와 니켈 금속혼합물을 침출시 낮은 반응온도에서 코발트가 선택적으로 침출됐다.

• 한국식품영양학회지
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• 제6권1호
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• pp.1-7
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• 1993

19 Samples of koji-starters using in brewing were collected from Korea and Japan, and then 31 strains of koji-molds were isolated from them. After Identification of the Isolate, rice koji was made with each strains, and its saccharogenic activity, dextrogenic activity, proteolytic activity, acid Producing ability, browning reaction and flavor were tested. Among 31 strains of isolates, 10 strains were Identified as Asp nwamori var. kawachii, 18 strains as Asp. oryzae, 3 strains as Asp. usamii mkt. shirousamii. The koji-starters made in Korea were composed of single species of koji-mold with same strain, but those made in Japan were composed of the mixture of different two species or the mixture of different 2 ∼4 strains in same species. Judging from amylolytic and proteolytic ability by species, Asp. awamori var. kawachii H1, I1 and 11, Asp. owsae J2, L2, M2, P3 and P4, and Asp. usamii writ. shirousamii S1 were better than the others. Mold strains isolated from Korean koji-starters were much lower in amylolytic or proteolytic activity than those from Japanese koji-starters. The typical characteristics for the 3 species of koji-molds were that Asp. awamori var. kawachii was strong in acid producing ability, but week in amylolytic and proteolytic ability, that Asp. owzae had strong amylolytic activity and good aroma, but produced little amount of acid, and that Asp. usamii mut. shirousamii had strong Proteolytic activity but some off-flavor.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.267-274
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• 2009

Two experiments were conducted to investigate the feeding value of wood vinegar in weanling pigs. In Experiment 1, weanling pigs (n = 224; Landrace ${\times}$Yorkshire ${\times}$Duroc, 21${\pm}$3 d-old, initial BW 6.12${\pm}$0.10 kg) were assigned to four dietary treatments. Different levels of wood vinegar were added to the diets as dietary treatments (0, 0.1, 0.2 and 0.3%). Each treatment comprised 4 replicates with 14 piglets in each. Experimental feeding was conducted for 28 d in two phases (phase I, d 0 to 14 and phase II, d 15 to 28). Feeding of wood vinegar linearly (p<0.05) improved the phase I, phase II and overall ADG and increased (linear, p<0.05) the overall and phase II ADFI. Linear improvements in the apparent fecal digestibility of dry matter (p = 0.013), gross energy (p = 0.019) and crude protein (p = 0.033) were observed as the level of wood vinegar was increased in the diet of pigs. Experiment 2 was conducted to compare dietary wood vinegar with commonly used growth promoters, organic acid (mixture of 21% phosphoric acid, 3.25% propionic acid, 2.8% formic acid, 10% calcium formate and 5% calcium propionate) and antibiotic (aparamycin). A total of 288 weanling piglets (Landrace ${\times}$Yorkshire ${\times}$Duroc, 22${\pm}$2 d-old, initial BW 6.62${\pm}$0.31 kg) were assigned to four treatments with four replicates (18 piglets/pen) for 28 days and fed in 2 phases: phase I, d 0 to 14 and phase II, d 15 to 28. The dietary treatments were control (corn-soybean meal basal diet without antibiotics) and diets containing 0.2% antibiotic, 0.2% organic acid and 0.2% wood vinegar. Pigs fed antibiotic showed higher (p<0.001) ADG and better feed efficiency followed by pigs fed wood vinegar and organic acid diets while those fed the control diet had lowest ADG and poorest feed efficiency. The overall and phase I ADFI was highest (p<0.001) in pigs fed wood vinegar and lowest in pigs fed the control diet. Apparent fecal digestibility of dry matter, gross energy and crude protein was significantly higher (p<0.05) in pigs fed the antibiotic diet when compared with pigs fed the control but comparable among pigs fed antibiotic, organic acid and wood vinegar diets. Higher populations of Lactobacillus (p = 0.004) were noted in the ileum of pigs fed the wood vinegar diet, while the population of coliforms in the ileum and cecum was higher (p<0.001) in pigs fed the control diet when compared with pigs fed antibiotic, organic acid or wood vinegar diets. These results indicated that wood vinegar could improve the performance of weanling pigs by improving the nutrient digestibility and reducing harmful intestinal coliforms; moreover performance of pigs fed wood vinegar was superior to those fed organic acid.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.2033-2037
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• 2014

A reaction mixture was developed for formation of soft organic monolith that was easily smashed, rinsed, refluxed, filtered, and dried to give monolith particles having high pore volume of macropores. This phase was almost without mesopores. The reaction mixture was composed of methacrylic acid, ethylene glycol dimethacrylate, polyethylene glycol (porogen), and an initiator in a mixed solvent of toluene and isooctane. The selection of porogen and its amount was carefully carried out to obtain the optimized separation efficiency of the resultant phase. The median macropore size was 1.6 ${\mu}m$, and the total pore volume was 3.0-3.4 mL/g. The median particle size (volume based) was 15 ${\mu}m$, and the range of particle size distribution was very broad. Nevertheless the column (1 ${\times}$ 300 mm) packed with this phase showed good separation efficiency (N~10,000-16,000) comparable to that of a commercial column packed with 5 ${\mu}m$ C18 silica particles.

• Nuclear Engineering and Technology
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• 제39권6호
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• pp.731-736
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• 2007

Radioactive organic wastes containing acetone, alcohol, and particularly tributyl phosphate (TBP)/dodecane contaminated with uranium are extracted from the PUREX process and the decontamination of related equipment. An evaporation method that utilizes existing DU oxidation apparatuses and ventilation systems and a typical muffle furnace installed with an aspirating system are adopted. A separation method using phosphoric acid especially for the TBP/dodecane waste is also studied and evaluated. The results show that a simple evaporation process is utilizable for wastes containing acetone or alcohol with a lower boiling point. A modified muffle furnace is more appropriate to dispose directly of organic wastes having a higher boiling point, such as TBP/dodecane, without generating a condensed waste solution. It is recommended that, when the uranium concentration of TBP/dodecane waste is much higher than stipulated levels, separation technology should be applied to remove uranium from the mixture. Each type of solvent after separation can then be considered disposable below the regulatory limit in the modified furnace discussed in this study.

• 한국미생물·생명공학회지
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• 제15권5호
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• pp.334-339
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• 1987

Pyruvic acid 생산 미생물로부터 얻어진 pyruvic acid의 tryptophan으로의 효소적 전환을 조사하였다. 발광 미생물인 Beneckea sp.가 pyruvic acid의 생산에 사용되었다. pyruvic acid, indole과 ammonia로 부터 tryptophan을 합성하는 tryptophanase의 효소원으로 Enterobacter aerogenes ATCC10031의 균체가 반응용액에 직접 사용되었다. Tryptophan의 생산량을 증가시키기 위해, 비이온성 계면활성제와 비 수용성 유기용매가 indole의 저장소로 사용되었다. 비이온성 계면활성제의 경우 triton X-100은 매우 효과적이였다. 1.5%의 triton X-100 이 사용되었을 때, 37$^{\circ}C$에서 48시간 동안에 7.7g/$\ell$의 tryptophan이 생산되었다. 비수용성 유기용매의 경우 10%의 benzene이 사용되었을 때, 37$^{\circ}C$에서 48시간 동안에 8.7g/$\ell$의 tryptophan이 생산되었다. 이 tryptophan의 양은 indole과 pyruvic acid를 기준으로 각각 48%와 36%의 전환율에 해당한다.