• 한국식품영양과학회지
• /
• 제29권2호
• /
• pp.241-247
• /
• 2000

The possibility of buckwheat-wheat flour mixture as bread was studied by adding 10, 20, and 30% of buckwheat to wheat flour. To improve bread-making quality of the mixture, gluten, ascorbic acid, and hydroxy propyl methyl cellulose (HPMC) were added to 30% buckwheat-wheat flour and sensory evaluation was also exercised on it. The weight of bread increased but the volume of that decreased as the percentage of buckwheat to wheat flour increased, and improved bread-making quality by adding gluten, ascorbic acid, HPMC to 30% buckwheat-wheat composite flour. When it comes to color, color of the bread got darker as the percentage of buckwheat increased, got brighter when gluten and HPMC were added and showed little difference when ascorbic acid was added. Texture of bread increased in maximum weight, strength, hardness but decreased in springiness and cohesiveness. The use of additives showed influence to the some results. In terms of the aging process, enthalpy increased with storage time, and it could be slowed down by the use of the additives. The sensory evaluation shwoed that 10% buckwheat-wheat bread was most excellent, 20% bread was similar to other bread made from wheat flour, and the bread made by mixing additives were better than just 30% buckwheat-wheat flour in terms of quality.

• Bulletin of the Korean Chemical Society
• /
• 제9권1호
• /
• pp.55-59
• /
• 1988

The gaseous carbon dioxide has been irradiated with Co-60 gamma-radiation in the presence and absence of various alcohols, and the radiolysis products analyzed by gas chromatography. Experimental results indicate that no detectable amount of carbon monoxide is formed when pure carbon dioxide is irradiated. By adding small quantities of alcohols to carbon dioxide, however, considerable amount of carbon monoxide, ketones, alcohols and other organic products have been detected. By adding 0.1% of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-l-propanol, 2-butanol, and 2-methyl-2-propanol, G(CO) values obtained are 4.4, 4.5, 5.2, 4.4, 5.2, 5.0, 4.7 and 4.1, respectively. These high yields of carbon monoxide suggest that the oxidation reactions of carbon monoxide may be suppressed by scavenging oxygen atom with the alcohols. The main radiolytic decomposition reactions of the alcohols present in small quantity in carbon dioxide may be supposed to be the reactions with the oxygen atom produced by the radiolysis of carbon dioxide. The decomposition reactions seems to follow pseudo-first order kinetics with respect to the alcohols. The decomposition rate measured with 2-propanol is the fastest and that with 2-methyl-2-propanol the slowest. The mechanisms of the radiolytic decomposition reactions of the alcohols present in carbon dioxide are discussed on the basis of the experimental results of the present study.

• Elastomers and Composites
• /
• 제38권1호
• /
• pp.65-71
• /
• 2003

저분자량 SBR (액상 SBR)이 실리카로 보강된 SBR 배합물의 특성에 미치는 영향에 대해 연구하였다. 액상 SBR을 실리카로 보강된 SBR 배합물에 첨가하면 점도가 낮아졌다. 가교밀도는 액상 SBR의 함량이 증가함에 따라 감소하였고 가창속도는 느려졌다. 모듈러스와 인장강도는 액상 SBR의 함량이 증가할수록 낮아졌고 신율은 증가하였다. 마모 특성은 액상 SBR의 함량에 따라 큰 차이를 보이지 않았다. 이는 액상 SBR의 첨가에 의해 실리카 분산이 향상되었기 때문으로 여겨진다. 실험결과를 종합해 볼 때, 5 phr 이하의 적은 양의 액상 SBR을 사용하는 것이 실리카로 보강된 SBR 배합물의 특성을 향상시키는데 바람직할 것으로 판단된다.

• 한국식품영양학회지
• /
• 제34권4호
• /
• pp.347-355
• /
• 2021

This study evaluated the quality and antioxidant activities of pork patties after adding Cirsium nipponicum powder in a ratio of 0%, 1%, 2%, 3%, and 4%, and the potential of Cirsium nipponicum as a functional food. The moisture content increased with an increase in the Cirsium nipponicum powder content while the pH, cooking loss rate, diameter loss rate decreased. The L and b values decreased with increase in the Cirsium nipponicum powder content while the a value increased; this trend was observed before and after heating the patties. The hardness, chewiness, and gumminess increased with increase in the Cirsium nipponicum powder content. Consumer acceptability test revealed that the 2% Cirsium nipponicum powder group had a higher score than the other groups in respect to color, flavor, taste, texture, and overall acceptance. Notably, as the Cirsium nipponicum powder content increased, there was an increase in the antioxidant activities; increased total pheonlic, flavonoid, DPPH radical scavenging activity and ABTS radical scavenging activity. Based on the present study results, adding 2% of Cirsium nipponicum powder into pork patties achieved the best functionality and sensory qualities.

• 열처리공학회지
• /
• 제34권2호
• /
• pp.53-59
• /
• 2021

Due to high specific strength and low density, AZ series magnesium alloys have been receiving high interest as a lightweight material. However, their industrial application is limited due to the phenomenon that the strength decreases at elevated temperature by the occurrence of softening effect because of the Mg17Al12 phase decomposition. To solve this problem, many research were conducted to increase the high-temperature strength by forming a thermal stable second-phase component by adding new elements to the AZ magnesium. Especially, adding Ca to AZ magnesium has been reported that Ca forms the new second-phase. However, studies about the analysis of decomposition or precipitation temperature, formation composition, and components to understand the formation behavior of these precipitated phases are still insufficient. Therefore, the effect of Ca addition to AZ61 on the phase change and microstructure of the alloy during annealing was investigated. As a result of analysis of the initial and heat-treated specimen, AZ61 formed α-Mg matrix and precipitated phase of Mg17Al12, and AZX611 formed one more type of precipitated phase, Al2Ca. Also, Al2Ca was thermal stable at high temperatures. And after annealing, the laves phase was decomposed to under 10 ㎛ size and distributed in matrix.

• 신재생에너지
• /
• 제17권3호
• /
• pp.8-15
• /
• 2021

In this study, we assessed the effect of vitamin components (such as biotin, thiamine-HCl, and folic acid) on microorganism microbial growth and ethanol production was examined to enhance increase the ethanol concentration in the Clostridium autoethanogenum culture process using syngas as a sole carbon source. Biotin and folic acid concentrations of 0.2, 2, 20, and 100 ㎍/L were used in the culture experiments at 0.2, 2, 20, and 100 ㎍/L concentrations. The maximum ethanol concentrations of 2.81 g/L and 3.12 g/L were obtained by adding at 0.2 ㎍/L biotin and folic acid, respectively. Moreover, Thiaminethiamine--HCl at concentrations of 0.5, 5, 50, and 250 ㎍/L were was examined evaluated to in the culture experiments. The maximum ethanol concentration of 2.84 g/L was observed at 0.5 ㎍/L of thiamine--HCl. As a resultThus, the optimized concentrations of biotin, thiamine--HCl, and folic acid were determined at 0.2, 0.5, and 0.2 ㎍/L, respectively, for enhancing increasing the ethanol production. In conclusion, the maximum ethanol production was obtained by adding the minimal concentration of vitamins in C. autoethanogenum culture.

• Earthquakes and Structures
• /
• 제20권4호
• /
• pp.417-430
• /
• 2021

Due to functional requirements, SRC column-RC beam abnormal joints with characteristics of strong beam weak column, variable column section, unequal beam height and staggered height exist in the Steel reinforced concrete (SRC) frame-bent main building structure of thermal power plant (TPP). This paper presents the experimental results of these abnormal joints through cyclic loading tests on five specimens with scaling factor of 1/5. The staggered height and whether adding H-shaped steel in beam or not were changing parameters of specimens. The failure patterns, bearing capacity, energy dissipation and ductile performance were analyzed. In addition, the stress mechanism of the abnormal joint was discussed based on the diagonal strut model. The research results showed that the abnormal exterior joints occurred shear failure and column end hinge flexural failure; reducing beam height through adding H-shaped steel in the beam of abnormal exterior joint could improve the crack resistance and ductility; the abnormal interior joints with different staggered heights occurred column ends flexural failure; the joint with larger staggered height had the higher bearing capacity and stiffness, but lower ductility. The concrete compression strut mechanism is still applicable to the abnormal joints in TPP, but it is affected by the abnormal characteristics.

• 한국수산과학회지
• /
• 제35권3호
• /
• pp.231-236
• /
• 2002

국내산 송이의 특징인 송이 향을 효과적으로 보존할 수 있는 방법을 개발하기 위하여 알긴산으로 송이 향의 주된 성분인 1-oc-ten-3-ol을 캡슐화 공정과 송이 향의 잔존량에 영향을 미치는 요인을 조사한 결과는 다음과 같다. 분무건조를 위한 alginates의 점도는 350cp 이하가 되어야 하므로, alginates 용액의 점도를 낮추기 위하여 첨가한 citric acid 량이 증가할수록 점도는 낮아졌으며, 또한 $0.1\%의 농도에서 150cp 이하의 점도를 나타내었다. 1-octen-3-ol과 유화제를 첨가하여 에멀젼시킨 alginates 용액의 점도는 에멀젼시키기 전의 점도보다 높았지만 150cp 이하를 나타내 분무 건조 공정에는 영향이 없었다. alginates 용액의 점도가 낮을수록 용액의 EAI는 증가하였으나 ESI는 감소하였고 캡슐의 1-octen-3-of의 잔존량이 감소하였다. alginates 용액의 점도를 낮추는 공정에서 citric acid 첨가 후 가열시간이 길어질수록 점도는 급격히 감소하였고 에멀전 전후의 점도는 큰 차이 없었다 생송이를 알긴 산용액으로 캡슐화할 때 첨가되는 대두유의 량이 많을수록 1-oc-ten-3-ol의 잔존량이 많았다. 생송이를 alginates용액으로 캡슐화한 후 진공동결건조한 캡슐이 풍건한 것보다 1-octen-3-ol의 잔존량이 많았다.

• Investigative Magnetic Resonance Imaging
• /
• 제18권2호
• /
• pp.157-166
• /
• 2014

목적 : 고식적 견관절 MRI 검사에 사각시상면 영상 추가 시 극상건 파열의 진단적 정확도가 증가하는지 관절경 수술 소견을 대비표준으로 삼아 알아보고자 하였다. 대상 및 방법 : 2011년 1월부터 2012년 12월까지 본원에서 견관절 MRI 검사를 하고 관절경 수술을 받은 121명의 환자를 대상으로 하였다. 두 명의 영상의학과 의사가 독립적으로 관상사면과 시상사면 영상을 이용하여 극상건 파열을 평가하고 4주후 사각시상면 영상을 추가하여 다시 판독하였다. 관절경 수술을 대비표준으로 이용하였다. 건 파열 진단의 민감도와 특이도는 McNemar test로 비교하였고 관찰자 간, 기술 간 일치도는 카파계수로 평가하였다. 결과 : 사각시상면 추가 시 고식적 견관절 MRI만 이용하였을 때 보다 극상건 전층 파열 진단의 민감도가 증가하였고, 부분 파열 진단의 민감도, 특이도, 정확도 모두 증가하였지만 통계학적으로 유의한 차이는 없었다. 관찰자간 일치도는 사각시상면을 추가하거나 하지 않았을 때 모두 높은 일치도를 보였다. 영상 소견과 관절경 수술 소견은 사각시상면 추가 시와 추가하지 않았을 때 모두 중등도의 일치도를 보였다. 결론 : 극상건의 전층 및 부분 파열 평가를 위해 고식적 MRI에 사각시상면 영상을 추가 시 기존의 영상면 만으로 평가하였을 때와 진단적 정확도에 의미 있는 차이는 없었다.

• 한국식품조리과학회지
• /
• 제21권5호
• /
• pp.669-676
• /
• 2005

클로렐라 가루를 0, 2, 4, 6%로 각각 달리 첨가하여 제조한 파운드케이크의 품질 특성을 조사하였으며 그 결과는 다음과 같다. 1. 반죽의 pH는 대조군이 7.08, 첨가군은 각각 7.13, 7.10, 7.10으로 pH가 증가하다가 감소하였다. 2. 중량은 대조군이 392.0 g, 첨가군은 각각 392.4, 389.2, 384.2 g으로 감소하였고, 부피는 대조군이 760.8 mL, 첨가군에서는 각각 801.8, 806.4, 839.2 mL로 유의적으로 증가하였다. 3. 부피지수와 굽기손실률은 클로렐라 첨가군에서 증가하는 경향이었고 수분흡수력은 클로렐라 첨가량이 증가함에 따라 유의적으로 증가하였다. 4. 경도는 1시간 방냉 시료의 경우 대조군이 0.74, 첨가군은 각각 0.67, 0.63, 0.65 kg으로 낮아졌고, 진입력은 대조군이 0.22, 첨가군이 $0.26{\sim}0.32\;kg$으로 높아졌으나 유의적 차이가 나타나지 않았다. 5. 색도에서 L값은 대조군 69.88에 비하여 클로렐라 첨가량이 많을수록 유의적으로 낮은 값을 나타내었고, a 값은 클로렐라 첨가량이 많을수록 음의 값을 나타내었으며 유의적인 차이를 보였다. 또한 b 값은 클로렐라 첨가량이 증가할수록 낮아지는 경향을 나타내었으며 유의적인 차이를 보였다. 6. 관능검사 결과 색상은 대조군 3.9, 첨가군이 $3.4{\sim}2.5$로, 냄새는 대조군 3.7, 첨가군이 $3.3{\sim}3.0$으로 유의적인 감소를 보였다. 맛과 전체적 기호도는 6% 첨가군에서 각가 2.8, 2.6으로 다른군에 비해 유의적으로 낮아졌다. 촉촉함과 씹힘성은 시료간에 유의적인 차이가 없었다.