• 한국재료학회지
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• 제32권12호
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• pp.533-537
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• 2022

Flexible zinc-air batteries have many merits, including low cost, high safety, environmentally friendliness applicability, etc. One of the key factors to improve the performance of flexible zinc-air batteries is to use a gel electrolyte. In this study, gel electrolytes were synthesized from potato, sweet potato, and corn starch. In a comparison of each starch, the corn starch-based gel electrolyte showed the highest discharge capacity of 12.41 mAh/cm² in 20 mA and 6.47 mAh/cm² in 30 mA. It also delivered a higher specific discharge capacity of 7.06 mAh/cm² than the other materials after 100° bending. In addition, the electrochemical impedance spectroscopy (EIS) was analyzed to calculate the ionic conductivity. The potato, sweet potato, and corn starch-based gel electrolytes showed electrolyte resistances (Re) of 0.306, 0.298, and 0.207 Ω, respectively. In addition, the corn starch-based gel electrolyte delivered the highest ionic conductivity of 0.121 S cm^-1 among the other gel electrolytes. Thus, the corn starch-based gel electrolyte was verified to improve the performance of flexible zinc-air batteries.

• 펄프종이기술
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• 제48권1호
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• pp.82-92
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• 2016

The reduction of carbon dioxide emission is hot issue in the world because we are confronted with serious global warming and climate change. As a part of carbon dioxide reduction efforts, various approaches for increasing filler loading have been carried out in order to decrease the energy consumption in papermaking processes. Effects of the pretreatment of GCC with cationic starch and MFC on the flocculation behaviour of GCC were investigated in this study. Pretreatment of GCC with cationic starch caused the change of electric charge of suspension and flocculation behaviour of GCC. Largest flocculation size was obtained near the isoelectric point in the case of cationic starch treatment. When MFC (30 times grinded) was added after preflocculation of GCC with cationic starch, the flocculation size was increased, but largest flocculation size was obtained at -150 mV of electric charge of suspension in this study. However the addition of highly grinded MFC (60 times grinded) caused smaller flocculation size of GCC than those of MFC (30 times grinded). When GCC and MFC were mixed first, and then cationic starch was added, the characteristics of MFC and the change of electric charge which could be brought by cationic starch did not affect the flocculation size of GCC at all. The flocculation size obtained by the combination of cationic starch and MFC was smaller than those of cationic starch. These results show that flocculation behaviour could be controlled by the change of electric charge of suspension and the combination methods of cationic starch and MFC.

• 폴리머
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• 제37권6호
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• pp.764-769
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• 2013

전분에 폴리(메틸 메타크릴레이트)(PMMA)를 그래프트시켜 starch-g-PMMA로 전분을 개질시켰다. 아크릴로니트릴 부타디엔 고무(NBR) 라텍스와 PMMA 그래프트 전분을 라텍스 블렌드 방법으로 혼합하여 개질된 전분/카본블랙/NBR 복합체를 제조하였다. 전분의 조성에 따라 모폴로지, 열적특성, 기계적 물성을 조사하였다. 전분/카본블랙/NBR 복합체는 전분의 함량이 증가함에 따라 물성이 향상되지만 40 phr 이상으로 전분이 들어가면 전분의 응집현상이 발생하여 분산성이 떨어지고 물성이 저하되는 현상을 관찰할 수 있었다. 25 phr의 전분과 25 phr의 카본블랙이 들어간 경우 우수한 분산성과 높은 가교 밀도에 기인하여 고무에 대한 보강성이 증가하였다. 또한 인장강도, 저장 탄성률, 경도, 팽윤도 등의 물성에서 가장 우수한 결과를 나타내었다.

• 한국식품조리과학회지
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• 제21권6호통권90호
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• pp.942-949
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• 2005

쌀전분겔의 매트릭스와 구조를 안정화하고 텍스쳐 특성을 개선하기 위하여 멥쌀전분에 다양한 검물질을 혼합하여 겔을 제조하여 형태적, 텍스쳐 특성, 냉동-해동 안정성을 비교하였다. 검물질을 첨가하면 종류에 따라 다르나 쌀전분겔을 조밀하고 균일하여 안정된 매트릭스 갖게 할 수 있었으며 겔란검과 알긴이 효과적이었다. 쌀전분/검질 혼합 겔의 텍스쳐 특성도 검질에 따라 달랐으며 겔란검은 단단하고 알긴은 부드러운 겔을 형성하였다. X-선 회절도에 의하면 쌀전분겔은 V형의 결정형을 나타내며 검을 첨가하였을 때 $2\theta$ = $20^{o}$의 피크가 낮아졌다. 냉동-해동 안정성도 검물질을 혼합하였을 때 증가하였으며 겔란검과 알긴을 첨가한 쌀전분겔이 바람직 하였다.

• 한국식품과학회지
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• 제30권4호
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• pp.803-810
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• 1998

도토리 전분의 노화에 대한 sucrose 영향을 관찰하기 위해서 기계적 성질과 열적 성질을 조사하였다. 정제 전분의 수분과 아밀로오스 함량은 각각 9.35%, 27%였다. 정제 전분의 중량 평균 분자량과 수 평균 분자량은 각각 $1.22{\times}10^6$과 $1.37{\times}10^5$이였고 다분산도는 8.90으로 아밀로오스, 아밀로펙틴 보다 높아서 도토리 전분은 불균일계임을 알 수 있었다. Creep 실험으로부터 sucrose 첨가 겔의 creep compliance는 저장 초기에는 sucrose 농도가 증가할수록 감소하였는데 이는 전분, sucrose와 전분내의 자유수와의 상호 작용에 의한 수소결합 형성에 기인한다. DSC 흡열곡선으로부터 호화온도와 엔탈피는 sucrose 농도가 증가할수록 증가하였다. 저장 후기에는 creep compliance가 농도가 증가할수록 증가하여 sucrose는 겔의 softness를 증가시킨다고 볼 수 있으며 재호화 엔탈피는 sucrose 농도가 증가하면 감소하였다. 호화 엔탈피와 재호화 엔탈피로부터 노화비율을 구하였고, sucorse 농도가 증가하면 노화비율은 감소하였다. 기계적 성질과 열적 성질 측정으로부터 sucrose는 도토리 전분의 호화와 노화를 지연시키는 작용을 함을 알 수 있었다.

• 한국식품과학회지
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• 제16권2호
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• pp.175-178
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• 1984

냉면 국수를 제조함에 있어 전분과 밀가루의 혼합비와 식염 및 알카리 첨가제의 첨가량에 따른 국수발의 기계적 성질의 변화를 creep test로 측정하였다. Creep test의 초기 변형율을 정확히 측정하기 위하여 VTR시스템으로 사진을 찍어 분석하였다. 국수발의 creep 커브는 Burgers의 4-element모델로 분석될 수 있었다. 반죽에 전분의 비율의 높아질수록 삶은 국수발의 순간 탄성치와 뉴우턴 점성치는 감소 하였다. 90% 전분을 포함한 반죽에 식염을 가할 경우 식염농도 4 % 수준까지는 순간탄성이 감소하였다. 알카리 첨가제 첨가시 국수발의 순간탄성, 지연탄성, 지연시간 및 뉴우턴 점성치들이 불규칙하게 변하였으며 그 효과를 일관성 있게 나타낼 수 없었다.

• Food Science and Biotechnology
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• 제16권5호
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• pp.817-821
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• 2007

The effect of acetylated rice (AR) starch at different concentrations (0, 4, 6, and 8%) on rheological properties of surimi sols and gels was studied. Dynamic frequency sweeps of surimi-AR starch sols at $10^{\circ}C$ showed that the magnitudes of storage moduli (G') decreased with an increase in starch concentration while those of tan ${\delta}$ increased, indicating that the effect of AR starch on the viscoelastic properties of surimi sols depended on starch concentration. In general, the G' thermograms of surimi sols showed the similar sol-gel transition pattern and they were also influenced by the addition of AR starch. The presence of AR starch in the surimi gel system reduced the gel strength and expressible moisture content (EMC). Surimi-AR starch gels showed better freeze-thaw stability compared to the control (0% starch concentration). The effect of AR starch on the rheological properties of surimi sols and gels appeared to be related to the swelling ability of starch granules in the presence of limited water available for starch.

• 동아시아식생활학회지
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• 제24권2호
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• pp.224-233
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• 2014

In this study, instead of arrowroot starch sesame mook(Gomadoufu) used in the manufacture of expensive sesame mook the quality of the material characteristics and commercialized for to find out the possibility of replacement of other starch, propose. Potato starch RVA analysis was quick pasting temperature $70.3^{\circ}C$, peak viscosity 740 RVU, break down 579.9 final viscosity 433.8, set back 275.7 arrowroot starch than 4.5 times, sweet potato starch than 6.9 fold the highest value showed Japanese sesame results starch (Atarigoma) concentration increased, the measured starch, different kinds of manufacturing quality characteristics of sesame mook tended to increase the moisture content, texture measurements on the hardness and springiness, gumminess and chewiness was gradually decreased. Sesame mook in sensory evaluation, color and aroma, taste, texture and overall-acceptability, sweet potato starch, arrowroot starch 60% addition, 50% added, potato starch 40% group containing most symbols highest was, and the experimental results used in the manufacture of arrowroot starch instead of expensive replacement of other starch is deemed.

• 펄프종이기술
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• 제48권2호
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• pp.99-105
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• 2016

The increase of wet web solid content after wet press and dry compressive strength were observed in lab study by judicious application of wood flour and starch for the old corrugated container (OCC). Pearl starch was better than cationic starch in strength development, but cationic starch was better for drainage. Application of vacuum on the mixed solution of wood flour and starch helped strength development further without loss of other properties. The effect of wood flour addition on wet web solid content improved as the wet pressing pressure increased. The use of wood flour and starch mixture improved wet web solid contents further.

• Food Science and Biotechnology
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• 제17권1호
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• pp.20-25
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• 2008

Effects of commercial and lab-generated gellan gums on the textural properties, structure, and aging of wheat and maize starch gels were investigated using a rapid visco-analyzer (RVA), rheometer, scanning electron microscope (SEM), and X-ray diffractometer. Gellan and guar gums increased the peak and final viscosities, but xanthan gum and gum arabic reduced them. The maize starch had higher breakdown viscosity than the wheat starch, regardless of the type of gum. The hardness of all starch gels increased during storage, but their cohesiveness and springiness decreased. The degree of the gel hardness showed higher in maize starch than in wheat starch and the effect of gum addition had a difference with gum type. The wheat starch-guar and -gellan gum mixed gels showed higher elasticity and cohesiveness after storage. The starch-gellan gum mixed gels had dense and stable network structures, and were well maintained even after 7 days of storage. Most of the gums had anti-aging effect on X-ray diffraction pattern of starch gels.