• 제목/요약/키워드: expansion of volume

검색결과 919건 처리시간 0.064초

중진공 표준기 자동화에 관한 연구 (A study on the system automation of medium-vacuum standard)

  • 홍승수;임인태;신용현;정광화
    • 한국진공학회지
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    • 제12권4호
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    • pp.207-213
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    • 2003
  • 중진공 국가표준기의 자동화를 위한 하드웨어 및 측정 프로그램 개발에 관한 연구를 수행하였다. 이 장치는 부피가 서로 다른 여러 개의 진공용기, 배기장치, 진공게이지, 온도계, 그리고 밸브 등 많은 부품들로 구성되어 있을 뿐만 아니라 복잡한 측정방법 때문에 자동화가 꼭 필요하다. 개발한 자동화 장치의 성능 평가를 위하여 진공용기의 부피율을 측정하고 용량형 격막식 진공게이지를 교정해 보았다.

제조 조건에 따른 증편의 품질 (Physicochemical Properties of Jeung-pyun (Fermented Rice Cake) as Influenced by Processing Conditions)

  • 서은주;류홍수;김상애
    • 한국식품영양과학회지
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    • 제21권1호
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    • pp.101-108
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    • 1992
  • 우리나라의 떡 중에서 맛, 질감 및 제조 방법이 독특한 것으로 알려진 증편의 제조 조건에 따른 이화학적 변화를 실험하여, 가정에서 증편을 만들 때의 표준조건을 구명하려 하였다. 품질에 영향을 미치는 요인 중 쌀가루 입자의 크기는 발효에 의한 부피 증대에 영향을 미치지 않았으며, 설탕을 첨가하지 않으면 부피가 거의 평창하지 않았다. 원료배합비는 쌀가루 : 탁주 :설탕 = 10 : 5 : 2(w/v/w), 발효온도 $35^{\circ}C$ 발효시간 3시간의 조건에서 부피 팽창이 가장 크게 일어났다. 발효된 반죽은 수증기로 찐후에 평균 $45{\sim}50%$정도 부피가 줄어드나 4시간 이상 발효시킨 것은 80% 가까이 부피가 줄어 들었다. 부피 평창이 가장 잘 일어나는 조건에서 발효시킨 반죽을 $10{\sim}15$분 쪄서 제조한 증편의 부피평창을, 소화율(환원력, blue value, 호화도), 관능검사 및 Instron Texturometer에 의한 질감 검사가 가장 우수 하였다. 즉 원료 배합비율은 쌀가루 : 탁주 : 설탕=10 : 5 : 2(w/v/w)이었고, 발효온도 $35^{\circ}C$, 발효시간 3시간, 찌는 시간은 $10{\sim}15$분이었다.

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개심수술후 혈량 증가를 위한 10% Pentastarch와 5% Albumin 용액의 비교연구 (10% Pentastarch Versus 5% Albumin Solution for Volume Expansion Following Cariopulmonary Bypass in Patients Undergoing Open Heart Surgery)

  • 장병철
    • Journal of Chest Surgery
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    • 제27권3호
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    • pp.177-186
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    • 1994
  • Pentastarch is a hydroxyethyl starch similar to hetastarch, but lower average molecular weight and fewer hydroxyethyl groups which result in enhanced enzymatic hydrolysis and faster renal elimination.This report was performed to compare the clinical efficacy and safety of 10 % pentastarch[Pentaspan , group I] for plasma volume expansion after open heart surgery with that of 5% albumin[Plasmanate, group II]. There were no statistically significant differences between the group I [n=18] and group II [n:19] in the preoperative parameters [age, sex, body weight] and operative parameters[bypass time, aorta cross clamping time]. During the first 24 hours after arrival of the patient in the surgical intensive care unit, colloid solution [500--1000 ml] was infused to maintain left atrial pressure of more than 8 mmHg, or cardiac index of 2.0 L/min/M2 of more. In results, there were 3 complications of hypotension immediately after infusion of 5 % albumin solution and 2 among the 3 patients were excluded for the study. However there was no complication after infusion of 10 % pentastarch solution. Hemodynamic responses to infusion was similar for both groups, although in group I a greater increase in both left atrial pressure[mean 1.8 versus 0.7 mmHg, p< 0.05] and right atrial pressure [mean 2.2 versus 1.7 mmHg, p < 0.05] was observed during infusion of the first 500 ml. There were no significant differences in any of the measured respiratory parameters[PaO2, intrapulmonary shunt, and effective lung compliance]. Homodilution with colloid significantly reduced hemoglobin [mean 1.2 versus 0.8 gm/dl], and serum protein and albumin level[total protein;4.8$\pm$ 0.5 versus 5.2 $\pm$0.5 gm/dl, p < 0.05: albumin: 3.2 $\pm$0.4 versus 3.6 $\pm$0.6 gm/dl, p < 0.05] by 6:00 AM on 1 day postoperatively, however there were no significant differences on 7 day postoperatively. The mean serum colloid osmotic pressure and osmolarity was similar in both group.There were no abnormal findings of liver function and kidney function in all the patients. There were no significant between-group differences in bleeding time, platelets, prothrombin time, activated partial thromboplastin time and amount of chest tube output measured on 1st and 7th postoperative day. These findings demonstrated that 10% pentastarch is more effective and safe for plasma volume expension than 5 % albumin solution with no adverse effects on coagulation. Also 10 % pentastarch is less expensive than 5 % albumin and it would appeare to be a reasonable first choice for plasma volume expansion.

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제올라이트 메소라이트의 수압 하 탄성특성 (Elastic Behavior of Zeolite Mesolite under Hydrostatic Pressure)

  • 이용재;이용문;성동훈;장영남
    • 자원환경지질
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    • 제42권5호
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    • pp.509-512
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    • 2009
  • 제올라이트 메소라이트($Na_{5.33}Ca_{5.33}Al_{16}Si_{24}O_{80}{\cdot}21.33H_2O$)에 대한 고압에서의 회절자료가 200 마이크론 크기로 단색화 된 방사광가속기 X-선원과 다이아몬드 앤빌셀을 사용하여 5 GPa까지 측정되었다. 물과 알코올을 사용한 수압 하에서 메소라이트의 초기 탄성 특성은 0.5 GPa에서 1.5 GPa 사이에서 일어나는 ab-평면의 연속적인 팽창과 c-축 상의 수축에 기인한 전체적인 격자부피의 팽창으로 관찰된다. 이후의 압력에서는 회절패턴의 변화로부터 질서-무질서 전이의 증거가 보여진다. 메소라이트의 c-축에 평행한 채널에는 양이온으로서 소디움과 칼슘이 b-축 방향으로 1:2 비율의 질서 있는 배열을 보이고 있는데 이로 인해 1.5 GPa까지 에서는 이러한 배열의 증거인 $3b_{natrolite}$ 격자패턴이 관찰된다. 격자부피의 확장 이후 1.5 GPa 이상에서 2.5 GPa 까지 에서는 격자부피 변화의 정도가 약해지며, 양이온의 무질서적인 배열에 의한 $b_{natrolite}$ 격자패턴이 관찰된다. 이후 압력의 계속된 증가는 점진적인 격자부피의 감소를 유발시키며 새로운 형태의 질서 있는 배열상을 지시하는 $3c_{natrolite}$ 격자패턴으로의 변화를 보여준다. 이로부터 압력에 의한 초수화 상태의 메소라이트는 질서-무질서-질서 형태의 채널 내부 혹은 채널간의 양이온 배열패턴 변화를 겪는 것으로 추정할 수 있다.

저미분 폐내화물 종류 및 혼입율 변화에 따른 혼화재 다량치환 모르타르의 공학적 특성 (High Volume Mineral Admixture Mortar According to Waste Refractory and Mixing Ratio)

  • 한상윤;박도영;차천수;김현우;윤기원;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 추계 학술논문 발표대회
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    • pp.134-135
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    • 2015
  • This study analysed compressive strength and the expansion characteristic to utilize a high volume mineral admixture mortar for a aerated mortar and a plastering mortar. In this experiment, the result shows that the compressive strength gain was satisfactory in case that WR was replaced within 5%. Also, the difference between WR1 and WR was insignificant. It shows that the drying shringkage properties at large was showed being satisfactory generally compared with Plain when WR was replaced, but the effect was not significant.

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분지 덱스트린 첨가가 냉동 소프트롤 반죽 및 빵의 저장 중 품질 특성에 미치는 영향 (Effects of Branched Dextrin on the Quality Characteristics of Frozen Soft Roll Dough and its Bread during Storage)

  • 박진희;임춘선;김일환;김문용
    • 한국식품조리과학회지
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    • 제27권5호
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    • pp.507-522
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    • 2011
  • In this study, samples of wheat flour and dough were prepared by adding of 1, 3, or 5% branched dextrin, which is produced from the amylopectin of waxy corn starch using a cyclization reaction with a branching enzyme. The samples were then evaluated qualitatively in terms of farinogram, viscogram, and extensogram characteristics. The fermentation power of dough expansion, extensogram characteristics, specific volume, baking loss, external/internal surface appearance, and sensory qualities were also examined after 4 weeks of storage at -20$^{\circ}C$ to determine the effect on freeze-thaw stability and quality improvement of branched dextrins in the soft roll bread formulation. Furthermore, the samples along with a control were compared regarding their quality characteristics, including changes in moisture content, water activity, color, and textural characteristics during a storage period of 4 days at 20$^{\circ}C$ to determine the effect on preventing retrogradation of the branched dextrin. As the branched dextrin content increased, area and extensibility increased, whereas water absorption, fermentation power of dough expansion, resistance/extensibility ratio, baking loss, and brownness of the crust decreased. However, the control group presented significantly higher peak viscosity, resistance, specific volume, taste, overall acceptability, moisture content, water activity, springiness, cohesiveness, and resilience values than those of the branched dextrin samples, whereas lightness, hardness, and chewiness showed the reverse effect. As the storage period increased, lightness, hardness, and chewiness increased, whereas cohesiveness decreased. In conclusion, the results indicate that adding 1~3% branched dextrin into a soft roll bread formulation from frozen dough had no positive effect on freeze-thaw stability or preventing retrogradation but may provide good nutritional properties.

백련차 분말을 대체한 우리밀 식빵의 품질 특성 (Quality Characteristics of Domestic Wheat White Bread with Substituted Nelumbo nucifera G. Tea Powder)

  • 김영숙;김문용;전순실
    • 한국식품영양학회지
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    • 제21권4호
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    • pp.448-456
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    • 2008
  • In this study, domestic wheat white breads were prepared with the substitution of 1.5, 3.0, 4.5, and 6.0% Nelumbo nucifera G. tea powder(NNTP). The samples and a control were then compared with regard to quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of NNTP in the formulation. As the NNTP contents increased, the pH of dough and bread, baking loss, and lightness decreased, whereas the total titratable acidity of dough and bread increased. The fermentation power of dough expansion increased with increasing incubation time. The NNTP samples evidenced significantly higher specific volume, greenness, yellowness, resilience, and crumb consistency than were observed in the control group. However, hardness and fracturability evidenced the opposite effect. The water content and uniformity of the crumb pores were highest at a substitution level of 1.5%, and were lowest at a level of 4.5%. Crumb color, flavor, and delicious taste decreased with increasing NNTP contents, whereas lotus leaf flavor, astringency, bitterness, and off-flavor increased. Density of the crumb pore and crumb springiness were not significantly different among the samples. Softness, chewiness, and overall acceptability were maximal with the 1.5% substitution, and were minimal in the 6.0% group. In conclusion, our results demonstrate that $1.5{\sim}3.0%$ NNTP may prove quite useful as a substitute for domestic wheat flour in the production of white bread, and may evidence favorable nutritional and functional properties.

루프소기방식을 갖는 2행정 프리피스톤 수소기관의 역화에 관한 연구 (Study on Backfire for a Two-Stroke Hydrogen Fueled Free-Piston Engine with Loop Scavenging)

  • 조관연;변창희;백대하;이종태
    • 한국수소및신에너지학회논문집
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    • 제21권6호
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    • pp.487-492
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    • 2010
  • For developing a two-stroke free-piston hydrogen engine with high efficiency and low emission, determination of the scavenging type is one of the most important factor. In this research, backfire characteristics for loop scavenging were analyzed with the number of piston crevice volume and piston expansion speed. Rapid Compression Expansion Machine, RCEM was used for combustion research of the free piston $H_2$ engine in the experiment. As the results, it was shown that although backfire occurring in a loop scavenging type can be partially controled by a complete exhaust of burned gas, possibility of backfire basically exist due to the structure which piston crevice volumes contact with fresh mixture in a scavenging port. However, a loop scavenging may be considered as combustion chamber of a free piston $H_2$ engine from the point of view that backfire does not occur nearby lean equivalence ratio obtained high thermal efficiency. It was also analyzed that an advances of backfire occurrence timing with increase of the fuel-air equivalence ratio were due to promotion of flame propagation into piston crevice volumes by decrease of the quenching distance.

헤미셀룰라아제를 첨가한 보리잎차 식빵의 품질 특성 (Quality Characteristics of Barley Leaves Tea White Bread with Hemicellulase)

  • 염경훈;김문용;전순실
    • 한국식품영양학회지
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    • 제23권2호
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    • pp.178-185
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    • 2010
  • Barley leaves tea white bread were prepared by the addition of 0.005, 0.010, 0.015, and 0.020% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough and bread among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Bread made by the addition of hemicellulase had significantly higher specific volume than the control group. However, lightness and yellowness showed the reverse effect. Greenness was not significantly different among the samples. Baking loss was the highest at the 0.020% addition level, and moisture content was maximal with the 0.010% addition, while the lowest in the control bread samples. As hemicellulase contents increased, harness and fracturability decreased. Resilience was maximal with the 0.015% addition, and was minimal in the 0.005% group. In the sensory evaluation, color, flavor, softness, overall acceptability, barley leaves flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. In coclusion, the results indicate that adding 0.010% hemicellulase in barley leaves tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

보리잎차 분말을 대체한 식빵의 품질 특성 (Quality Characteristics of White Bread with Barley Leaves Tea Powder)

  • 염경훈;김문용;전순실
    • 한국식품조리과학회지
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    • 제26권4호
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    • pp.398-405
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    • 2010
  • In this study, white bread was prepared containing 1.5, 3.0, 4.5 or 6.0% barley leaves tea powder (BLTP). The samples along with a control were then compared regarding their quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, internal surface appearances and sensory qualities, all to determine the optimal ratio of BLTP. As the BLTP content increased, the pH of the dough and bread and the lightness decreased, whereas the total titratable acidity increased. The fermentation power of dough expansion increased with a longer incubation time. The control group was evidenced by a significantly higher specific volume and baking loss than that observed in the BLTP samples. However, greenness and yellowness evidenced the opposite effect. Hardness was highest at a substitution level of 1.5% and lowest at a level of 4.5%. Fracturability and resilience were not significantly different among the samples. For the internal surface appearance, darkness and greenness increased both increased at higher BLTP content. In the sensory evaluation, color, flavor and overall acceptability were highest in the control bread samples but minimal at a substitution level of 6.0%. Softness was the highest at the 3.0% substitution level and lowest in the control bread samples. Barley leaf flavor, astringency, bitterness and off-flavor increased as the BLTP content increased. Delicious taste was not significantly different among the samples. In conclusion, the results demonstrated that 4.5% BLTP may prove quite useful as a substitute for wheat flour in the production of white bread and may provide favorable nutritional and functional properties.