• Carbon letters
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• 제8권2호
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• pp.115-119
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• 2007

Properties of carbon blacks and carbon black/SBR rubber composites filled by surface modified carbon blacks were examined. Although the specific surface area of carbon blacks increased after the surface modifications with heat, acid, and base, there were no obvious changes in resistivity. The composites filled by heat treated carbon blacks showed a higher tensile strength and elongation than those filled by raw blacks. The acid and base treated carbon blacks filled composites also showed higher tensile strength but similar elongation values with those filled by raw blacks. With increasing loading ratio, both tensile strength and elongation increased, and appeared a maximum value at 30-40 phr. Modulus at 300% strain remained increasing with further loading of carbon blacks. At the same loading, the heat treated black filled composites showed similar modulus values with composites filled by raw blacks but for base and acid treated black filled composites much higher values were obtained. After the surface modification, the functional groups which played an important role in reinforcement action were changed.

• Macromolecular Research
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• 제12권3호
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• pp.293-302
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• 2004

We added surface-modified silica nanoparticles to poly(ethylene 2,6-naphthalate) (PEN) to investigate their effect on the mechanical properties on the PEN nanocomposite material. The torque and total torque values of the composites decreased in the silica nanoparticle composites. The tensile modulus of the composites reinforced with unmodified silica nanoparticles increased upon increasing the silica content, while the tensile strength and elongation decreased accordingly. In contrast, stearic acid-modified, silica nanoparticle reinforced PEN composites exhibited an increase in elongation and a decrease in tensile modulus upon addition of the silica nanoparticles because the stearic acid that had adsorbed onto the surface of the silica nanoparticle in multilayers could act as a plasticizer during melt compounding. Stearic acid modification had a small effect on the crystallization behavior of the composites. We calculated theoretical values of the tensile modulus using the Einstein, Kerner, and Nielsen equations and compared these values with the experimental data obtained from the composites. The parameters calculated using the Nielsen equation and the Nicolais- Narkis model revealed that the interfacial adhesion between silica nanoparticles and the PEN matrix could be improved.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.59-60
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• 2016

Flooded lead acid batteries are still very popular in the industry because of their low cost as compared to their counterparts. State of Charge (SOC) estimation is of great importance for a flooded lead acid battery to ensure its safe working and to prevent it from over-charging or over-discharging. Different types of Kalman Filters are widely used for SOC estimation of batteries. The values of process and measurement noise covariance of a filter are usually calculated by trial and error method and taken as constant throughout the estimation process. While in practical cases, these values can vary as well depending upon the dynamics of the system. Therefore an Adaptive Unscented Kalman Filter (AUKF) is introduced in which the values of the process and measurement noise covariance are updated in each iteration based on the residual system error. A comparison of traditional and Adaptive Unscented Kalman Filter is presented in the paper. The results show that SOC estimation error by the proposed method is further reduced by 3 % as compared to traditional Unscented Kalman Filter.

• Animal Bioscience
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• 제35권3호
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• pp.453-460
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• 2022

Objective: The objective was to test additivity of digestible energy and nutrient concentrations in the hatchery byproduct mixture fed to nursery pigs. Methods: In the previous studies, energy, phosphorus, calcium, and amino acid digestibility of infertile eggs, unhatched eggs, culled chicks, and a mixture of 3 hatchery byproduct ingredients was determined in nursery pigs (initial body weight = 9.4 to 14.2 kg). An additivity test was conducted using these determined values. Results: No difference was observed between determined and predicted metabolizable energy values in the mixture (3,998 and 3,990 kcal/kg as-is basis, respectively). Measured standardized total tract digestible phosphorus in the mixture was less than the predicted value (4.5 vs 5.3 g/kg as-is basis, respectively; p<0.05). Measured standardized total tract digestible calcium in the mixture was greater compared with the predicted value (40.0 vs 31.7 g/kg as-is basis, respectively; p<0.05). Measured standardized ileal digestible tryptophan in the mixture was greater than the predicted value (3.7 vs 3.1 g/kg as-is basis, respectively; p<0.05) whereas other amino acid values were additive. Conclusion: Energy and most of amino acid concentrations in hatchery byproducts are additive in the mixture fed to nursery pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제2권1호
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• pp.27-34
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• 1989

Different fractions of maize plant and whole mixed fodder were analysed for their chemical composition and dry matter digestibility (DMD). Highest crude protein (CP) values were found in leaves as compared to the other portions. Younger plants contained more CP as compared to the matured ones. The crude fiber (CF) content of various fractions of the plant ranged between 19.12 to 35.60% with maximum values in the bottom portion of the stem. Matured plants contained more CF. The analysis of cell wall constituents indicated that the maximum values for neutral detergent fiber (NDF) were found in the bottom portion and in the whole mixed plant. The highest levels of acid detergent fiber (ADF) were observed in bottom fraction followed by whole mixed plant, whereas the other plant fractions did not show any differences. Variation in acid detergent lignin (ADL) values existed in different fractions of the plant and the lowest were in the top portion of the stem. Although there existed a variation in the mineral composition of different fractions of the plants, the results were non significant. Maximum DMD was found in leaves followed by the whole mixed plant, middle and bottom portion of the stem. The values of DMD were higher in younger plants as compared to the matured ones. It may be concluded that younger plants and the upper portion of the plants have a higher nutritive value as compared to the matured plants and lower portion of the plants.

• Journal of Animal Science and Technology
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• 제48권2호
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• pp.269-278
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• 2006

본 실험은 오리 가슴육의 저장성 향상에 대안을 마련하고자 차염소산나트륨 20, 50ppm, lactic acid와 acetic acid를 각각 1, 2%를 분무 살포한 후 진공포장지로 포장하여 4℃에서 7일간 저장을 하면서, 소독제 및 유기산 처리에 따른 오리육의 육색, 저장특성 및 미생물 증식에 대하여 조사하였다. 오리육의 차염소산나트륨 20～50ppm 및 유기산(lactic acid, acetic acid)을 1～2% 처리 후 1일이 경과했을 때 pH는 5.83～5.87로 처리 간에 큰 차이가 없었고, 저장기간에 따라서는 저장 3일까지 증가하는 경향을 나타내다 점차 감소하였다. 지방산패도(TBARS)는 저장기간이 경과함에 따라 차염소산나트륨 처리구보다 유기산 처리구(lactic acid와 acetic acid)에서 감소하는 경향이 크게 나타났으며, 특히 acetic acid 2% 처리구에서 감소율이 컸다. 비 단백질태 질소화합물(VBN)은 저장기간이 경과할수록 증가하였으나, 차염소산나트륨 및 유기산의 종류와 처리 수준에 따라서는 큰 차이를 나타내지 않았다. 육색 변화는 lactic acid 2% 처리 구에서 적색도(a*) 및 황색도(b*)가 약간씩 감소하는 경향을 나타내었다. 소독제 및 유기산 처리에 따른 총 미생물 수는 저장기간이 경과할수록 증가하는 경향을 나타냈으나, 유기산 처리구 중 acetic acid 처리구가 저장 기간 중 미생물 증가율이 가장 낮았으며, 특히 acetic acid 2% 처리 구에서 낮은 증가율을 나타내었다.

• 한국약용작물학회지
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• 제14권5호
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• pp.299-302
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• 2006

Three known triterpenoids were isolated from MeOH extract of C. apiifolia (Ranunculaceae). Their structures were identified as oleanolic acid (1), ursolic acid (2), hederagenic acid (3) by comparison of their physicochemical and spectral data with the literature values. Among them, 2 was isolated for the first time from this plant. The isolated compounds were evaluated for their cytotoxicity against L1210, HL-60, SK-OV-3 tumor cell lines. All compounds 1-3 were shown good activities with $IC_{50}$ values ranging from 7.7 to $25.6\;{\mu}g/ml. This result suggests that triterpenoids 1-3 are main cytotoxic principles of this plant.

• KSBB Journal
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• 제13권4호
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• pp.461-467
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• 1998

A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

• 분석과학
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• 제17권6호
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• pp.476-480
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• 2004

A simple, rapid, reproducible and selective UV-Visible spectrophotometric method has been developed for determination of germanium in a week acid medium (pH = 3.0) in the presence of mandelic acid (MA) and malachite green (MG). A single extraction in chlorobenzene was used for the analysis. The germanium-MA ion association complex exhibits an absorption maximum at ${\lambda}_{max}=618nm$ with MG as counter ion and has an apparent molar absorptivtity of $1.313{\times}10^5L\;mol^{-1}\;cm^{-1}$. The values obtained by this UV-Visible spectrophotometric method are in good agreement with the values from inductively coupled plasma-mass spectrometer analysis.

• 한국응용과학기술학회지
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• 제12권1호
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• pp.69-79
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• 1995

Ham, sausage and bacon were treated with common household processing techniques including refrigerated storage(0, 14, 28 days) and cooking(pan-frying, microwaving, boiling). Lipid oxidation was evaluated by measuring fatty acid composition, malonaldehyde(MA), TBA values and by measuring fluorescent products. Major fatty acid composition were oleic acid and followed respectively palmitic acid, stearic acid, linoleic acid, linolenic acid. There was no significant difference in fatty acid composition by cooking method but there was a tendency of being increased of unsaturated fatty acid during 28days storage. Ma, TBA and fluorescent products showed a tendency of being increased continually according to storage days rather than cooking method.