• 대한화장품학회:학술대회논문집
• /
• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
• /
• pp.60-72
• /
• 2003

To investigate the effect of cholesterol in liposome on the stability of incorporated retinol, the physico-chemical experiments for various amounts of cholesterol-containing liposomes were performed. Liposome with retinol containing cholesterol was prepared as multilamella vesicles(MLVs) by dehydration/rehydration method. The incorporation efficiency of retinol into liposome was maximized as 99.31 % at 50:50 (phosphatidylcholine/cholesterol) at pH 9. The stability of incorporated retinol at low storage temperature was enhanced with increasing cholesterol content than at high storage temperature. For example, incorporated retinol in liposome at glycine buffer(pH 9} was degraded slowly during storage at 4. The degradation of retinol in liposomes was slower at pH 9 than at pH 7. These results supported that cholesterol in liposome increased largely the stability of incorporated retinol.

• 한국안전학회지
• /
• 제18권3호
• /
• pp.60-63
• /
• 2003

For the increase the charge stability of teflon electrets for used at uncomfortable industrial circumstances with high temperature or humidity, We made an investigation into double layer effect of teflon electrets. Teflon AF film was spincoated on FEP film and then the charge storage property of AF/FEP dual film was investigated to be compared with FEP film. It was found that the AF/FEP dual film has higher surface potential than FEP film on the repeated charging and annealing process. It seems that AF/FEP dual film has higher thermal stability than FEP film through TSC measurement. If the investigations of the double layer effect of Teflon film carried out more closely with it's molecular structures and surface conditions, it may be effectively improved the stability of charge storage.

• The Journal of Advanced Prosthodontics
• /
• 제9권3호
• /
• pp.182-187
• /
• 2017

PURPOSE. Vinyl polyether silicone (VPES) has a different composition from other elastomeric impression materials as it combines vinyl polysiloxane (VPS) and polyether (PE). Therefore, it is important to study its properties and behavior under different test conditions. This study investigated the dimensional stability of 5 VPES consistencies when stored for up to 2 weeks, with and without using a standard disinfection procedure. MATERIALS AND METHODS. 40 discs of each VPES consistency (total 200) were made using a stainless steel die and ring as described by ANSI /ADA specification No. 19. 20 discs of each material were immersed in a 2.5% buffered glutaraldehyde solution for 30 minutes. Dimensional stability measurements were calculated immediately after fabrication and repeated on the same discs after 7 and 14 days of storage. The data was analyzed using two-way ANOVA with a significance level set at ${\alpha}=0.05$. RESULTS. The discs mean contraction was below 0.5% at all test times ranging from $0.200{\pm}0.014$ to $0.325{\pm}0.007$. Repeated measures ANOVA showed a statistically significant difference after 2-week storage between the disinfected and non-disinfected groups (P < .001). Although there was no statistically significant difference between the materials at the time of fabrication, the contraction of the materials increased with storage for 1 and 2 weeks. CONCLUSION. The dimensional changes of VPES impression discs after disinfection and prolonged storage complied with ANSI/ADA standard. The tested VPES impression materials were dimensionally stable for clinical use after disinfection for 30 minutes in glutaraldehyde and storage for up to 2 weeks.

• 한국식품조리과학회지
• /
• 제31권1호
• /
• pp.62-71
• /
• 2015

The purpose of this study was to evaluate the changes on the characteristics of the oxidative stability of Tenebrio molitor larvae during cold storage at $4^{\circ}C$. Pretreatment for T. molitor larvae was designed into three methods: raw (R), freeze-dried (F.D.), and pan-fried (P.F.). The water content of the raw sample (61.46%) was higher than those of other samples (F.D.: 5.02%, P.F.: 3.67%) and its high water content was expected to facilitate the oxidation of the raw sample. In our results, the peroxide value and the carbonyl value of all of the samples increased and the raw sample, after storage for 18 day, showed the highest value. The pan-fried sample had no significant increase in its lactic acid content, acid value, and thiobarbituric acid value; whereas those values were increased in the raw sample and the freeze-dried sample (p<0.05). The browning reaction was more progressed in the pan-fried sample than other samples at 0 day, but there was no significant change during the storage. The raw sample and the freeze-dried sample had their browning indexes increase with the increasing storage period (p<0.05). The pan-fried sample produced less oxidation products than the freeze-dried sample, indicating that the unheated sample was more susceptible to oxidation than the heated samples. In conclusion, heating treatment and low water content would be effective for improving the safety and stability of T. molitor larvae during cold storage.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2009년도 춘계학술대회 논문집
• /
• pp.735-736
• /
• 2009

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2009년도 춘계학술대회 논문집
• /
• pp.151-152
• /
• 2009

• 한국식품영양학회지
• /
• 제30권5호
• /
• pp.960-972
• /
• 2017

The objectives of this study was to investigate the properties and stability of the wet noodles added to nanoemulsion as a industrial model system, and in so doing, survey practical applicability in the food industry. In order to test out these objectives, the characteristics and stability of the wet noodles added to nanoemulsion were investigated and their cooking characteristics and capsaicinoids loss were examined. As a result, the test results showed that the findings indicated that the post-cooking loss of capsaicinoids in the wet noodles added to double-layer nanoemulsion covered with chitosan was less than the losses in the wet noodles added to any other noodles. More especially, this demonstrates that the noodle added to double-layer nanoemulsion covered with chitosan scored significantly higher than the others with reference to their cooking properties, color, texture, stability for storage stability, and sensory evaluation. These results show that the findings of this study demonstrated that the noodles added to nanoemulsions could be produced as a food-grade merchandise because they could provide enhanced encapsulation capacity of capsaicinoids and higher acceptability.

• Journal of Electrochemical Science and Technology
• /
• 제15권1호
• /
• pp.14-31
• /
• 2024

The text highlights the growing need for eco-friendly energy storage and the potential of metal-organic frameworks (MOFs) to address this demand. Despite their promise, challenges in MOF-based energy storage include stability, reproducible synthesis, cost-effectiveness, and scalability. Recent progress in supercapacitor materials, particularly over the last decade, has aimed to overcome these challenges. The review focuses on the morphological characteristics and synthesis methods of MOFs used in supercapacitors to achieve improved electrochemical performance. Various types of MOFs, including monometallic, binary, and tri-metallic compositions, as well as derivatives like hybrid nanostructures, sulfides, phosphides, and carbon composites, are explored for their energy storage potential. The review emphasizes the quest for superior electrochemical performance and stability with MOF-based materials. By analyzing recent research, the review underscores the potential of MOF-based supercapacitors to meet the increasing demands for high power and energy density solutions in the field of energy storage.

• Animal Bioscience
• /
• 제34권4호
• /
• pp.701-713
• /
• 2021

Objective: The present work was undertaken to evaluate the effects of storage time, choline chloride, and high concentrations of Cu and Zn on the kinetic behavior of vitamin degradation during storage in two vitamin premixes and four vitamin-trace mineral (VTM) premixes. Methods: Two vitamin premixes (with or without 160,000 mg/kg of choline) were stored at 25℃ and 60% humidity. Besides, four VTM premixes were used to evaluate the effects of choline (0 vs 40,000 mg/kg) and trace minerals (low CuSO4+ZnO vs high CuSO4+ZnO) on vitamin stability in VTM premixes stored in room, and the VTM premixes were stored in room temperature at 22℃. Subsamples from each vitamin and VTM premix were collected at 0, 1, 2, 3, 6, and 12 months. The retention of vitamin A (VA), vitamin D3 (VD3), vitamin E (VE), vitamin K3 (VK3), vitamin B1 (VB1), vitamin B2 (VB2), vitamin B3 (VB3), vitamin B5 (VB5), and vitamin B6 (VB6) in vitamin premixes and VTM premixes during storage was determined. The stability of vitamins in vitamin premixes and VTM premixes was determined and reported as the residual vitamin activity (% of initial) at each sampling point. Results: The effect of choline on VK3 retention was significant in vitamin premixes (p<0.05). The negative effect of storage time was significant for the retentions of VD3, VK3, VB1, VB2, VB5, and VB6 in vitamin premix (p<0.05). For VTM premixes, negative effect of storage time was significant (p<0.05) for the losses of vitamin in VTM premixes. Choline and high concentrations of Cu and Zn significantly increased VA, VK3, VB1, and VB2 loss during storage (p<0.05). The supplementation of high concentrations of Cu and Zn significantly decreased the concentrations of VD3 and VB6 (p<0.05) in VTM premixes at extended storage time. Conclusion: The maximum vitamin stability was detected in vitamin and VTM premixes containing no choline or excess Cu and Zn. The results indicated that extended storage time increased degradation of vitamin in vitamin or VTM premixes. These results may provide useful information for vitamin and VTM premixes to improve the knowledge of vitamin in terms of its stability.

• 한국식품과학회지
• /
• 제31권1호
• /
• pp.106-109
• /
• 1999

S. epidermidis에 의해 치자황색소에서 변환된 청녹계색소와 치자황색소의 저장안정성에 미치는 광, 온도, pH, 무기이온에 의한 영향을 조사하였다. 두 색소는 광과 $40^{\circ}C$ 이상의 온도조건에서 변색에 영향을 받았으나, 변환된 색소가 보다 안정성이 있으며, 광에 의한 영향은 green filter에 의해 감소시킬 수 있었다. pH와 무기이온에 의한 영향은 두 색소 모두 작았다.