• 한국해양바이오학회지
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• 제14권2호
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• pp.112-123
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• 2022

Photosynthetic bacteria (PSB) play an important role in water purification, and their application is beneficial for sustainable aquaculture. However, maintaining the microbial stability of PSB from subculturing to preservation is a challenging task. Since improvement in the microbial stability of PSB is a crucial parameter, optimized conditions for cell immobilization and lyophilization were investigated. In PSB immobilization, 0.1-M CaCl₂ was found to be the most effective divalent metal ion solution in terms of cost-effectiveness, resulting in beads with a 4-mm diameter and high loading (1.91×10⁹ CFU/mL) of viable cells. Maintenance of cell viability, external appearance, and color of PSB beads was best in 3.5% NaCl during storage. In lyophilization, the addition of skim milk (9%) and dextrose (2%) as cryoprotective additives allowed the highest cell viability. Over an 18-week shrimp breeding period, when optimally manufactured beads and lyophilized powder of PSB were applied to shrimp aquaculture water, NH⁴⁺, NO₃^-, and NO₂^- were more effectively removed by 55%, 100%, and 100%, respectively, compared to controls. Thus, microbial stability of PSB through optimized cell immobilization and lyophilization was successfully enhanced, enabling a wide application.

• Journal of Pharmaceutical Investigation
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• 제21권3호
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• pp.161-170
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• 1991

The storage stabilities of immunoliposomes incorporated with variable amounts of ganglioside $G_{M1}$ were investigated as a function of time. temperature. and composition by observing absorbance of visible light and calcein release. In the column chromatographe, the layer of unsaturated PE(dioleoylphosphatidylethanolamine : DOPE). unable to form stable liposomes at physiological temperature and pH, were formed when palmitoyl-immunoglobulin G(IgG) $(2.5{\times}10^{-4}\;mol/DOPE\;mol)$ added. The incorporation of ganglioside $G_{M1}$ into immunoliposome. enhanced the stabilities of bilayers during the extended period of storage. The turbidities of immunoliposomes coated with ganglioside $G_{M1}$ exhibited the maximum near 20 mol% $G_{M1}/DOPE$ mol. probably because of the disturbance of the bilayer characteristics, i.e., layer transition or reorientation of interaction sites. At low temperature. the higher stability was achieved than at elevated temperatures. After one week of storage. the redispersed liposomal solutions at lower temperatures maintained the original elution patterns in chromatography but broader distribution at elevated temperatures. During the storage, it is suggested the aggregation is the more dominant phenomena for liposomes kept at $5^{\circ}C$ than the fusion. while he fusion is at elevated temperatures.

• Asian-Australasian Journal of Animal Sciences
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• 제32권9호
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• pp.1439-1447
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• 2019

Objective: The aim of this study was to evaluate the effect of dietary incorporation of tanninrich woody species on meat oxidative stability, carcass traits and meat quality in goats. Methods: Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat. Results: Feed intake, liveweight gain, carcass, and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups. Conclusion: The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.499-503
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• 2003

Encapsulation of L-ascorbic acid (vitamin C) within a bio-compatible layered inorganic material was achieved by coprecipitation reaction, in which the layered inorganic lattice and its intercalate of vitamin C are simultaneously formed. The nano-meter sized powders of vitamin C intercalate thus prepared was again encapsulated with silica nano-sol to form a nanoporous shell structure. This ternary nanohybrid of vitamin Clayered inorganic core-$SiO_2$ shell exhibited an enhanced storage stability and a sustained releasing of vitamin C. Furthermore, the nano-encapsulation of vitamin C with inorganic mineral was very helpful in delivering vitamin C molecules into skin through stratum corneum, facilitating transdermal penetration of vitamin C in topical application.

• Food Science and Biotechnology
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• 제14권5호
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• pp.604-607
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• 2005

In this study, the effect of ${\beta}$-sitosterol (SS) in the liposome bilayer on the stability of incorporated retinol was evaluated. Retinol was incorporated into liposomes consisting of various ratios of soybean phoaphatidylcholine (PC) to SS, while liposomes were prepared as multilamellar vesicles by the dehydration/rehydration method. Retinol was readily incorporated into liposomes with various SS contents, with incorporation efficiencies higher than 98% for all conditions. The incorporation efficiency of retinol increased slightly as the SS content in liposomes increased. Its average particle size also increased as the SS content increased. Mean particle size at PC to SS ratios of 100:0, 90:10, 80:20, 70:30, 60:40, and 50:50 were 12.16, 17.57, 35.00, 40.62, 83.45, and $88.94\;{\mu}m$, respectively. Liposomal retinol degradation in aqueous solution was measured with respect to SS content at various periods of time at four different temperatures of 4, 25, 37, and $50^{\circ}C$, and the stability of the incorporated retinol enhanced as the SS content increased. At $4^{\circ}C$, for example, retinol in the liposomes of 50:50 (PC:SS) remained at 84.42% after storage for 10 days, while in 100:0 (PC/SS) it remained at 42.62%. These results indicate that SS content in liposomes played an important role in the incorporation efficiency of retinol and its stability.

• 미생물학회지
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• 제35권1호
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• pp.89-93
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• 1999

시판 요구르트 제품중 Lactobacilli 및 Bifidobacteria 의 안정성과 내산성을 비교 고찰하였다. 요구르트 제품중 Lactobacilli 및 Bifidobacteria 의 안정성 및 내산성은 제품들간에 큰 차이가 있음을 고찰하였다. 요구르트 제품중 Lactobacilli 및 Bifidobacteria 의 생존률은 저장중 시간이 지남에 따라 점차 감소하였으나 $10^7$-$10^8$ cfu/ml로의 생존률을 나타내었다. 요구르트 제품중 Lactobacilli 및 Bifidobacteria의 생존률은 pH가 낮아짐에 따라 점차로 감소하였다. 인공위액에서 2시간 노출시킨 후 Lactobacilli 및 Bifidobacteria의 생존률은 3개의 제품에서 $10^3$-$10^4$ cfu/ml 이상이었으나 캡슐제품에 함유된 Bifidobacteria 의 생존률은 $10^8$cfu/ml 이상으로 크게 향상되었다.

• 한국수산과학회지
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• 제20권2호
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• pp.146-151
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• 1987

정어리유의 산화 안정성과 지질추출시에 첨가한 BHA에 의한 저장중의 산화방지효과를 정토하고 산화로 인한 지방산 조성의 면화를 조사한 결과를 요약하면 다음과 같다. 1. BHA는 유리 지방산의 생성을 현저히 억제하는 효과가 있었다. 2. BHA는 과산화물 생성을 억제하였으며 특히 카르보닐 화합들의 생성을 아주 강하게 억제하였다. 즉 BHA는 과산화을 분해를 억제하는 작용이 있었다. 3. 정어리유는$C_{20:5}$와 $C_{22:6}$의 함량이 $23\%$ 이상으로서 매우 높았다. 4. 산화에 의한 지방산의 감소는 polyene 산에서 급격하였으며 특히 $C_{20:5}$와 $C_{22:6}$산이 급격히 감소하였다. BHA 첨가는 $C_{22:5}$와 $C_{22:6}$산의 산화를 크게 억제 할수 있었다.

• 한국분말재료학회지
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• 제30권6호
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• pp.509-515
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• 2023

Lead-free perovskite ceramics, which have excellent energy storage capabilities, are attracting attention owing to their high power density and rapid charge-discharge speed. Given that the energy-storage properties of perovskite ceramic capacitors are significantly improved by doping with various elements, modifying their chemical compositions is a fundamental strategy. This study investigated the effect of Zn doping on the microstructure and energy storage performance of potassium sodium niobate (KNN)-based ceramics. Two types of powders and their corresponding ceramics with compositions of (1-x)(K,Na)NbO₃-xBi(Ni_2/3Ta_1/3)O₃ (KNN-BNT) and (1-x)(K,Na)NbO₃-xBi(Ni_1/3Zn_1/3Ta_1/3)O₃ (KNN-BNZT) were prepared via solid-state reactions. The results indicate that Zn doping retards grain growth, resulting in smaller grain sizes in Zn-doped KNN-BNZT than in KNN-BNT ceramics. Moreover, the Zn-doped KNN-BNZT ceramics exhibited superior energy storage density and efficiency across all x values. Notably, 0.9KNN-0.1BNZT ceramics demonstrate an energy storage density and efficiency of 0.24 J/cm³ and 96%, respectively. These ceramics also exhibited excellent temperature and frequency stability. This study provides valuable insights into the design of KNN-based ceramic capacitors with enhanced energy storage capabilities through doping strategies.

• Applied Microscopy
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• 제36권spc1호
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• pp.57-61
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• 2006

High-resolution microscopy was applied for surveying hydride stability in Vanadium alloys, which are candidate for hydrogen storage materials of advanced hydrogen energy systems. $V_2H$ hydride in V alloys was stable at room temperature under the vacuum condition, but it was decomposed during heating up to $100^{\circ}C$. It was confirmed from HRTEM image and FFT that $V_2H$ has a BCT structure, where hydrogen atoms locate at octahedral sites. Crystal orientation was <110> beta// <110> mat., and lattice strain is about 10%. After the decomposition of the hydride, relatively large lattice expansion was observed in the matrix, which suggests that hydrogen atoms should be trapped by lattice defects and included in the matrix. Intensive electron beam also enhanced the decomposition.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.300-309
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• 2010

Melamincyanurate(MC), as an non halogen flame retardant are used as the polymer and plastic materials. In this study, melamine and cyanuric acid were used for the synthesis of MC. The optimum condition of synthetic MC were controlled by different molar ratio of melamine to cyanuric acid. MC was modified by coupling reaction with four different agents. The influences of modified MC were based on the coupling agent types. Preparation methods are available to offer the prospect of improved morphology control deposit stability in polyol. The results reveal that glycidoxypropyltrimethoxysilane(GDS) has the best storage stability. The best properties were obtained with melamine and cyanuric acid from 1:1 molar ratio. Modification of MC through coupling agent can efficiently enhanced the deposit stability in polyol up to 30 %.