• 한국자기공명학회논문지
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• 제4권1호
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• pp.50-63
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• 2000

Titanium dioxide particles with three different average sizes, prepared by three different methods, were incorporated into silica gel pores by impregnation. The titanium dioxide incorporated into the silica gel pores was photoionized by 240-400 nm irradiation at 77 K by a one-photon process to from trapped hole centers on OH group and trapped electron centers on titanium which were detected by electron paramagnetic resonance at 77 K. During the impregnation the smallest size range of TiO2 particles can be incorporated into silica gels with 2.5-1.5 nm pores. However, the largest size range of TiO2 particles can only be incorporated into silica gels with 6-15 nm pores and not into silica gels with 2.5-4 nm pores. The photoyield and stability of photoinduced hole and electron centers depends on the silica pore sizes of silica gels and surface area as well as on the TiO2 loading. In large pore silica gels and large particle size of TiO2, photoinduced charge separation reaches to a plateau at shorter irradiation times and the trapped hole and electron centers are more stable to decay.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.370-370
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• 2006

Thermoplastic elastomer gels, which has molecular networks composed of a microphase-separated multiblock copolymer swollen to a large extent by a low volatility mid-block selective solvent such as white oil have various applications. In this particular study, the effect of several network-forming nanoscale fillers such as two different graphite particles and carbon nanotube on the properties of TPE gels prepared from a microphaseordered poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) triblock copolymer with an EB compatible white oil was studied. The linear viscoelastic behavior, sol-gel transition, x-ray diffraction and mechanical properties were discussed. The properties of thermoplastic elastomer gels hybrid with graphite prepared by mixing Poly(styrene-b-ethylene-co-butylene)-b-styrene) with paraffin oil and different amount of expandable graphite were found to increase the mechanical properties at only lower graphite concentration but tends to decrease when paraffin oil/SEBS ratio is lower. The gelation temperature is the same for all TPE gels with different amounts of graphite. Both storage (G') modulus loss (G") modulus of TPE gels slightly increase with addition of graphite.

• 한국식품조리과학회지
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• 제19권6호
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• pp.758-764
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• 2003

This study was performed to determine the quality characteristics of mixed polysaccharide gels made from kcarrageenan and locust bean gum with various kiwifruit content after freeze-thawing. The syneresis, rupture properties, TPA properties and sensory properties of the mixed polysaccharide gels with various kiwifruit contents after freeze-thawing were measured. The syneresis of the gel with various kiwifruit contents by freeze-thawing was not significantly different, whereas repeating freeze-thawing resulted in remarkable increase in the syneresis of the mixed polysaccharide gels with 5％, 20％ and 40％ kiwifruit. In terms of the rupture properties, the rupture stress, rupture energy and rupture strain decreased with increasing kiwifruit content after freeze-thawing. In terms of the TPA properties, the adhesiveness, hardness and chewiness increased and the cohesiveness decreased with increasing kiwifruit content after freeze-thawing. The rupture properties, springiness and cohesiveness of the gel by freeze-thawing were lower than those of the gel stored in the refrigerator. In contrast, the gumminess, hardness and chewiness of the gel after freeze-thawing were higher than those of the gel stored in the refrigerator. The results showed that the gel became crumbly and tough as a result of freeze-thawing. In the sensory evaluation, He overall acceptability of the gel after freeze-thawing was highest at the 30％ kiwifruit content, and differences in the sensory properties between the gel after freeze-thawing and that stored in the refrigerator were small. Therefore, mixed polysaccharide gels with kiwifruit after freeze-thawing could be useful despite the small decrease in quality.

• Fisheries and Aquatic Sciences
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• 제16권3호
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• pp.143-147
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• 2013

The influence of carrageenan addition on the gelatinization of salt-based surimi gels was investigated by measuring compressive properties and Hunter color scale values. Hydrocolloid kappa (${\kappa}$)-carrageenan at 0%, 0.2%, and 1.0% and NaCl (2% w/w), KCl (1.5% w/w), and a mixture of NaCl (2% w/w) and KCl (1.5% w/w), were added to Alaska pollock surimi. Gel compressive properties were assessed by measuring the breaking force and gel strength. The gelling property of ${\kappa}$-carrageenan-induced surimi gel was significantly increased by the incorporation of KCl rather than NaCl. The addition of ${\kappa}$-carrageenan increased the breaking force and gel strength of surimi gels. Gels with 1% ${\kappa}$-carrageenan and KCl had the highest breaking force and gel strength. The addition of ${\kappa}$-carrageenan caused an increase in the whiteness values of the surimi gels.

• 한국식품조리과학회지
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• 제17권4호
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• pp.391-398
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• 2001

녹두전분 겔을 온도(5$^{\circ}C$, $25^{\circ}C$) 및 기간(1, 24, 48, 72시간)별로 저장하여 겔의 열적 특성, 점도 특성, 효소소화도, X-선 회절도, 미세구조의 변화를 조사하였다. DSC 실험 결과 5$^{\circ}C$ 저장시 $25^{\circ}C$ 저장시보다 용융피크가 저온측에 있고, 용융엔탈피 값은 더 큰 값을 나타내어 저온에서 겔의 노화가 빠르게 진행됨을 나타내었다. RVA에 의한 점도 측정 결과 $25^{\circ}C$에서 3일간 저장한 시료를 제외하면, 5$^{\circ}C$ 및 $25^{\circ}C$ 저장 모두 peak 점도, 최종점도 등의 점도 특성이 저장에 의해 증가하였는데, 이러한 현상은 5$^{\circ}C$ 저장시 보다 현저하였다. 효소소화도는 저장기간이 경과함에 따라 감소했으며, 이러한 경향은 5$^{\circ}C$ 저장시 더 현저하였다. X-선 회절도는 $25^{\circ}C$ 저장시에는 매우 약한 피크가, 5$^{\circ}C$ 저장에서는 보다 강한 피크가 관찰되었지만, 동일 온도에서 저장한 시료 사이의 차이는 구별하기 어려웠다. 주사전자현미경에 의한 미세구조 관찰 결과 모든 겔에서 잘 발달된 망상구조가 관찰되었으며, $25^{\circ}C$에서 저장시에는 3일째에 전분쇄의 망상구조가 두꺼워졌고, 5$^{\circ}C$ 저장시는 저장 초기부터 망상구조가 두꺼워졌다.

• 대한가정학회지
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• 제42권2호
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• pp.213-227
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• 2004

This study was attempted to investigate the sensory and textural characteristics of mungbean starch gels with soy bean oil and sucrose fatty acid ester(SE) addition during room temperature storage. Freshly prepared mungbean starch gels, with and without soy bean oil and SE, were stored at 25$^{\circ}C$ for 24, 48 and 72 hours. The color value, syneresis, texture and sensory properties of the gels were measured. The lightness(L) of the gels with soy bean oil and without additives was similar whereas that with SE was lower than that without additives. Syneresis of the gels with soy bean oil and SE was lower than that without additives. Rupture stress, rupture strain and rupture energy of the freshly prepared gel with 2∼4% soy bean oil were increased, but there were no differences in rupture properties between the gel with soy bean oil and that without additives. Rupture stress, rupture stain and rupture energy of all the gels with SE were decreased. Addition of soy bean oil to the gel did not change the texture profile of the gel, whereas hardness, springiness and chewiness of the gel with SE were decreased. In sensory evaluation, the acceptability of freshly prepared gel with soy bean oil was similar to that without additives, whereas that of the gel with 2% soy bean oil stored for 24 hours was higher than that without additives. The acceptability of the gel with SE was decreased significantly.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.115-115
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• 1997

A new capsaicin analog modified with 4-hydroxyl and alkyl chain of capsaicin was a very potent antiinflammatory analgesic drug and may be clinically useful for those who have rheumatoid arthritis, diabetic neuropathy and cancer. The purpose of this study was to investigate histopathology after short and long term application of poloxamer-based gels, and percutaneous absorption of various topical formulations. Poloxamer-based gel was prepared by cold method using poloxamer 407. The poloxamer gels was applied to dorsal sites of hairless mouse skin during one week or one month for the evaluation of skin irritation. The applied site was then sectioned for histopathologic examination. The topical formulations were also prepared using CMC, HPMC, MC, carbopol and glycerylmono stearate. Skin variation of poloxamer gels was studied using excised hairless mouse, rat, hamster and human penis skin. Franz-type diffusion cells were used far skin penetration of drug against receptor phase filled with about 10$m\ell$ of 0.9% saline solution kept at 32$^{\circ}C$. The concentration of drug was determined by the reverse phased C18, Symmetry HPLC with fluorometeric detector. No skin erythema was observed after dorsal application of poloxamer-based gels for one week or one month. No histopathologic changes was also examined, suggesting no skin toxicity of poloxamer-based gels. The order of flux rate was HPMC > MC ( CMC > poloxamer >> glycerylmono stearate ( carbopol. There was a skin variation of poloxamer gels. The flux rate of poloxamer gels was highest in case of hairless mouse followed by rat, human and hamster skin. The Partial support-Ministry of Science and Engineering (HAN project).

• 한국식생활문화학회지
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• 제26권5호
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• pp.513-520
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• 2011

This study was carried out to investigate the physicochemical properties of mung bean starch and the texture of cold-stored (5$^{\circ}C$ for 0, 24, 48, and 72 hours) mung bean starch gels added with soy bean oil (0, 2, 4, 6%). The swelling power of mung bean starch added with soy bean oil did not significantly change, whereas solubility increased significantly. Soluble carbohydrate content of mung bean starch added with soy bean oil decreased without any significant differences, whereas soluble amylose content decreased significantly. In RVA viscosity, pasting temperature and peak viscosity of mung bean starch added with soy bean oil were not significantly different, whereas minimum viscosity decreased and breakdown and consistency increased significantly. In RVA viscosity, there were no differences according to concentration of soy bean oil. DSC thermograms show that onset temperature of mung bean starch added with soy bean oil did not significantly change, whereas the enthalpy increased in the case of 4% and 6% oil addition. Rupture properties of freshly prepared mung bean starch gels added with soy bean oil increased in the case of 2% and 4% oil addition, and oil addition to mung bean starch gels suppressed changes in rupture properties during cold storage. There were no significant differences in the texture of freshly prepared mung bean starch gels added with soy bean oil, whereas hardness, chewiness, and gumminess of cold-stored mung bean starch gels added with soy bean oil decreased. In the above textural charactristics, there were no differences due to concentration of soy bean oil. Thus, the addition of 2-4% soy bean oil to mung bean starch is appropriate for improving the quality characteristics of cold-stored mung bean starch gels.

• 한국식품과학회지
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• 제25권6호
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• pp.698-702
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• 1993

온도 증가에 따라 용출되는 soluble carbohydrate는 온도가 증가할수록 더 큰 분자들이 많이 용출되었고 동부나 녹두는 아주 유사한 용출 양상을 보였다. 그리고 팥은 동부나 녹두보다는 분자량이 작지만 강낭콩보다는 큰 분자들이 용출되었고 $95^{\circ}C$에서의 용출양상이 동부나 녹두의 $85^{\circ}C$에서의 용출양상과 비슷해지는 것을 알 수 있었다. 그러나 강낭콩은 온도가 증가되어도 아주 작은 분자들이 계속 많이 용출되어 강낭콩 아밀로오스가 작은 분자들로 이루어져 있다는 것을 시사했다. 텍스쳐실험결과 전분겔의 특성은 녹두가 가장 견고성이 크고 동부는 응집성이 가장 컸다. 팥이나 강낭콩은 견고성과 응집성 모두 동부나 녹두에 비해 낮았다. 15분간 가열하여 제조한 전분겔의 경우 가열온도가 증가할수록 견고성과 응집성이 증가하였다. 1시간 가열하여 제조한 전분겔의 경우 동부와 녹두는 $85^{\circ}C$에서보다 $95^{\circ}C$에서 견고성이 감소하였으나 팥이나 강낭콩은 가열온도 증가에 따라 견고성이 증가하였고 시료 전분겔 모두 응집성은 증가 하는 양상을 보였다.

• 한국식품과학회지
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• 제25권6호
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• pp.626-631
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• 1993

쑥의 첨가로 물결합능력, 팽윤력, 용해도는 모두 증가 하였으며 이는 쑥의 이런 성질이 쌀가루보다 크기 때문이었다. 쑥의 첨가로 페이스트의 점도는 상승하였으나, 저장중($25^{\circ}C,\;4^{\circ}C$에서 7일)에는 페이스트와 쑥첨가 페이스트의 점도가 모두 뚜렷하게 변하지 않았다. 겔은 쑥첨가로 더 단단해졌으며 저장중 경도는 쌀가루 겔과 쑥첨가겔이 모두 크게 증가하였고 특히 $4^{\circ}C$ 저장의 경우 심하였다. Glucoamylase에 의한 가수분해 방법으로 측정한 페이스트와 겔의 저장중의 호화도는 제조직 후의 $94{\sim}100%$에서 7일 저장 후 $92{\sim}98%$로 감소하였다. 쌀가루 겔의 냉동-해동시 안정성은 쑥에 의해 영향을 별로 받지 않은 것으로 나타났다.