• 자원리싸이클링
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• 제32권1호
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• pp.33-41
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• 2023

본 연구에서는 제강분진으로부터 습식제련을 이용하여 아연을 선택적으로 회수하고 황산아연을 제조하고자 하였다. 제강분진의 성상분석을 통해 기존의 제강분진과 다르게 철의 함유량이 9.9%로 상대적으로 낮고 망간이 19%로 다량 함유되어 있었으며 이에 알맞은 습식제련 공정을 설계하였다. 침출공정에서는 고액비, 온도, 황산 농도별 실험을 통해 1.6M 황산, 20% 고액비, 60℃, 1시간동안 침출하여 85%의 아연, 망간을 용해시키고 철은 침출되지 않았다. 망간으로부터 아연을 선택적으로 회수하기 위해 D2EPHA를 사용한 용매추출 공정을 선택하였고 0.8M D2EHPA, 32% 비누화도, O/A 비 2, 향류 3단 추출을 통해 에서 99% 아연을 추출하였으며, 공동 추출된 망간은 pH 1.5로 조정한 황산 수용액으로 전량 세정하였다. 최종적으로 1.5M 황산을 이용하여 O/A 비 4, 향류 4단 탈거를 통해 아연을 농축 탈거하였다. 탈거액에는 40g/L의 아연이 함유되어 있었으며 이를 감압증류하여 99.9%의 황산아연 1수화물을 획득하였다.

• 한국식품과학회지
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• 제48권2호
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• pp.122-127
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• 2016

아사이베리의 특징적인 향기성분을 동정하기 위하여 SAFE와 LLCE를 이용하여 추출하고 GC-MS와 GC-O로 분석하였다. 아사이베리에서 공통적으로 동정된 휘발성 향기성분은 2-phenylethanol, (Z)-3-hexenol과 benzyl alcohol 등으로 함량이 높았으며 8-hydroxy linalool과 maltol은 LLCE에서 높은 함량을 나타내었다. 아사이베리의 휘발성 향기성분은 알코올류가 가장 함량이 높았으며 아사이베리의 중요한 휘발성 향기성분이라고 생각된다. 아사이베리의 향 활성 화합물 중 ${\beta}-damascenone$은 SAFE에서 $log_2FD=4$와 LLCE에서 $log_2FD=1$을 나타냈으며 장미향과 베리향 특성을 나타내어 아사이베리의 특징적인 향에 기여하는 중요한 화합물이라 생각된다. 또한 trans-linalool oxide, (Z)-3-hexenol과 2-phenylethanol 등이 아사이베리의 향 활성 화합물로 동정되었다.

• 대한간호학회지
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• 제1권1호
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• pp.103-110
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• 1970

It is important to point out that the percental mortality rate of the multiple pregnancy is almost twice of the single pregnancy due mainly to their prematurity and the mothers of twins will also be suffered from the plural births to nurse and take care of them. We therefore studied the incidence, the sex ratio, the types of deliveries, the complications and the percental mortality rate of the twin deliveries in order to promote the development of our field of maternal and child nursing. We selected our materials from the 112 patients who had been admitted and delivered twins in the department of OB. & Gyn. of the S.N.U. Hospital from Jan. 1962 to Dec. 1969. The abstructed results of this study were as follows. 1. The incidence of twins among 7, 731 births was 1:69 2. The occurrence of twins from elder multigravida was 4 to 6 times higher than younger primigravida mothers under 35 years of age. 3. The generational length of 45.5% of all twins was under 38 weeks and the mean birth weight of 1st and 2nd twins were 2, 354.7gm and 2, 215.8gm respectively. 4. The sex ratio of twins was 99 males and 124 females. 5. Presentation of twins: 59 cases (52.69%) were in both vertex. 37 cases (33.03%) in vertex plus breech. 15 cases (13.39%) in both breech and one case (0.89%) in transverse presentation. 6. For the types of deliveries Spontaneous deliveries were in 90 babies (40.6%) Breech extraction in 60 babies (26.3%) Vacuum used in 33 babies (15.0%) Cesarean section in 33 babies (9.8%) Forceps in 9 babies (4.2%) and others such as version and destructive measures in 9 babies (4.1%) 7. Intervals between the 1st and 2nd delivery were analyzed and 93% of 2nd twins were delivered within minutes after 1st delivery. 8. The main complications of twin deliveries were totemic (45.5%), second was postmarital hemorrhage (19.6%) and third was hydrations (7.1%) 9. The mean percental mortality of 1st and 2nd twins was 12.52% and 16.96% respectively of which main cause of death were their prematurity.

• 한국식품영양과학회지
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• 제33권3호
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• pp.603-608
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• 2004

제주 전통두부의 산업 를 위한 최적 공정을 확립하고 해수를 대용할 수 있는 응고제를 사용하여 맛과 영양성 및 저장성이 향상된 고품질의 전통두부를 생산할 수 있었다. 즉 대두원료의 침지는 동절기 및 하절기에 각각 12∼16시간, 8∼10시간이 적합하였다. 가수량은 원료 대두량의 8배가 적합하였으며, 이 때의 두유농도는 8$^{\circ}$Brix였다. 두유는 10$0^{\circ}C$에서 2분 정도 가열하는 것이 단백질의 유리 thiol잔기의 노출을 최대화하였다. 연속 가열솥 대신 진공솥으로 대치한 결과 압력과 온도조절이 용이하여 수율이 21% 증가하였으며, 제품의 품질관리가 용이하였다. 마른두부의 응고제로는 6% 죽염액과 다시마침출액을 1 : 1의 비율로 혼합하여 1차 응고제를 만들고, 키토산 1 L에 CaCl$_2$8g과 MgCl$_2$ 2g의 비율로 혼합하여 응고제를 얻었다. 최종 마른 두부의 소비자의 기호도는 60%이상이 보통 이상으로 평가하였으며, 고소한 맛과 견고성이 우수하면서 전체적인 기호도가 시판두부에 비해서 유의적인 차이를 보이면서 우수하였다.

• 한국균학회지
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• 제11권2호
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• pp.91-95
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• 1983

한국산 담자균류의 항종양성 성분을 탐색하기 위하여 턱수염버섯의 균사를 분리하여 인공배지에서 진탕배 양후, 그 배양균사체로부터 수용셩 단백성 다당류를 추출하였다. 이 성분이 ICR마우스에 이식한 육종 180에 대하여 54.3%의 종양억제율을 나타내었다. 이 성분은 다당류 42%와 단백질 28%로 구성되어 있었다. 그 중 다당류는 glucose (57.8%), mannose(19.3%), galactose(10.8%), xylose (6.8%), 및 fucose (5.7%)를 함유하고 있었다.

• 한국수산과학회지
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• 제48권5호
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• pp.668-673
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• 2015

The pacific oyster Crassostrea gigas has a desirable taste and flavor that differs from those of other fish and shellfish. In order to develop a high value-added product from individually quick-frozen oyster extract (IQFOE), we prepared an oyster sauce from IQFOE and characterized its volatile compounds using vacuum simultaneous steam distillationsolvent extraction / gas chromatography / mass spectrometry. The moisture, crude protein, crude ash, salinity, pH and volatile basic nitrogen contents of the oyster sauce were 60.6%, 8.2%, 9.2%, 9.3%, 5.7 and 21.0 mg/100 g, respectively. Seventy-six volatile compounds were detected in the cooked odor of the oyster sauce. These volatile compounds included 14 esters, including ethyl acetate, 13 nitrogen- containing compounds, including 2,4,6-trimethyl pyridine, 13 acids, including hexadecanoic acid, 12 alcohols, including ethyl alcohol and 6-methyl heptanol, 6 alkanes, 5 aldehydes, including benzaldehyde, 5 ketones, including 1-(2-furanyl)-ethanone, 4 furans, including 2-furancarboxaldehyde and 2-furanmethanol, 3 aromatic compounds, including d-limonene, and 1 miscellaneous compound. Esters, acids and nitrogen-containing compounds, and alcohols were the most abundant compounds in the odor of the cooked oyster sauce, with some aldehydes, ketones, and furans.

• 생약학회지
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• 제33권4호통권131호
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• pp.364-371
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• 2002

Yew (Taxus cuspidata Sibe) selected cultivation as drug, food and decorative plant in Gyong-gi province in Korea. To extract the water soluble active ingredients, as a extracting method, there was extracted with 20g of dried seeds with each 20g of butylene glycol(BG) and propylene glycol(PG), and 40 mL of water mixing 72 hours at $40{\pm}5^{\circ}C$, and then they were filtrated by 400 mesh. Appearance of extract of seeds was pale brown, $pH=4.5{\pm}0.5$, $gravity=1.013{\pm}0.05$, a reflective $index=1.373{\pm}0.05$, and yield=75%. Also, to extract the high purity oil from seeds, it minutely pulverized the dried seeds and added the hexane, mixing 2 hours at $20{\pm}57^{\circ}C$. And then, this filtrated it with 400-mesh. It got the purified oil through evaporating them at $55^{\circ}C$ during under vacuum. As the results, appearance was slightly brown, gravity=0.922 acid value=0.12, saponification value=192, and it should be obtained the $40{\pm}5%$ of yield. As the efficacy evalution of cosmetic field, the antioxidative activities by NBT method were stronger 86.0% from extract of talus seeds than 52.0% from green tea extract and 35.0% from skullcap extract as well as the antioxidative activities by DPPH method were stronger 93.7% from extract of seed than 60.3% from extract of green tea and 27.1% from extract of skullcap. These are more effective than other plant extracts. The collagen synthesis rate on the activating fibroblast for Taxus cuspidata Sibe extract showed 35.43%. As the activity of the skin elasticity, PPE(porcine pancreatic elastase)-inhibitory activities of talus extract was 50.8%. Anti-inflammatory activity was more effective to be taken 41.1% of taxus seed oil than 24.2% of steady glycyrrhetinate (SG) as a control.

• Journal of Advanced Marine Engineering and Technology
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• 제40권6호
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• pp.458-467
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• 2016

소금은 인간의 생리활동에서 매우 중요한 물질로서 섭취한 영양소를 혈액 안으로 수송하는 역할을 한다. 따라서 소금에는 카드늄, 수은, 납, 비소와 같은 유해성분이 전혀 포함되지 않는 것이 가장 이상적이다. 그러나 소금은 모든 물질이 용존 되어 있는 해수로부터 얻어지기 때문에 기술적 한계로 불가불 미량의 유해성분이 포함되는 것을 법적으로 용인하고 있다. 본 논문은 해수의 농도증가에 따른 순차석출 현상을 응용하여 '$15^{\circ}C$ 저온진공건조기술'로 유해성분이 전혀 포함되지 않는 식탁염의 새로운 제조방법에 대한 실험결과를 보고하였다. 본 연구결과를 전통적인 천일염의 제조공정에 확장 적용하면 세계적 명품 소금의 제조도 가능하다.

• 한국분말재료학회지
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• 제18권3호
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• pp.262-268
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• 2011

In order to investigate the microstructure and mechanical properties of WC-10 wt% Co insert tool alloy fabricated by PIM (Powder Injection Molding) process, the feedstock of WC-10 wt% and wax used as a kind of binder were mixed together by two blade mixer. After injection molding, the debinding process was carried out by two-steps. First, solvent extraction, in which the binder was eliminated by putting the specimen into normal hexane for 24 hrs at $60^{\circ}C$, and subsequently thermal debinding which was conducted at $260^{\circ}C$ and $480^{\circ}C$ for 6 hrs in the mixed gas of $H_2/N_2$, respectively. Meantime, in order to compensate the decarburization due to hydrogen, 1.2~1.8% of carbon was added to ensure the integrity of the phase. Finally, the specimens were sintered in vacuum under different temperatures, and the relative density of 99.8% and hardness of 2100 Hv can be achieved when sintered at $1380^{\circ}C$, even the TRS is lower than the conventional sintering process.

• 한국분말재료학회지
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• 제21권3호
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• pp.215-221
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• 2014

Translucent alumina is a potential candidate for high temperature application as a replacement of the glass or polymer. Recently, due to the increasing demand of high power light emitting diode (LED), there is a growing interest in the translucent alumina. Since the translucent property is very sensitive to the internal defect, such as voids inside or abnormal grain growth of sintered alumina, it is important to fabricate the defect-free product through the fabrication process. Powder injection molding (PIM) has been commonly applied for the fabrication of complex shaped products. Among the many parameters of PIM, the flowability of powder/binder mixture becomes more significant especially for the shape of the cavity with thin thickness. Two different positions of the gate were applied during PIM using the disc type of die. The binder was removed by solvent extraction method and the brown compact was sintered at $1750^{\circ}C$ for 3 hours in a vacuum. The flowability was also simulated using moldflow (MPI 6.0) with two different types of gate. The effect of the flowability of powder/binder mixture on the microstructure of the sintered specimen was studied with the analysis of the simulation result.