• 한국수산과학회지
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• 제52권6호
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• pp.562-570
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• 2019

To develop natural-tasting fish paste from the pufferfish Lagocephalus wheeleri, steamed pufferfish paste (SPP) was prepared and its optimal processing conditions, quality metrics, and shelf-life characteristics were examined. SPP was produced by thawing golden threadfin Nemipterus virgatus surimi (FA grade), then adding 10% unwashed pufferfish surimi (PS), 1.5% salt, 8.0% wheat starch, 0.25% calcium carbonate, 0.25% sugar, 0.75% sorbitol, 0.25% polyphosphate, and 12.0% pufferfish hot-water extract (Brix 10°). The meat was ground with a Stephan mixer, molded at low temperature (18℃, 10 h), vacuum packed in a laminated plastic film bag, heat treated with hot water (95℃, 50 min), and cooled. As the amount of PS added increased, the whiteness, gel strength, and shear strength of the SPP decreased slightly. However, the SPP folding test showed no deterioration in the texture. In the sensory evaluation, the SPP received a higher rating for taste, smell, and overall taste than commercial Japanese pufferfish Kamaboko. The total amino acid content of the SPP was 10,262.6 mg/100 g; the major amino acids were aspartic acid, glutamic acid, alanine, valine, leucine, lysine, and arginine. The free amino acid content was 133.0 mg/100 g; the major amino acids were taurine, glutamic acid, glycine, alanine, cystine, and lysine.

• Advances in nano research
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• 제12권1호
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• pp.73-79
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• 2022

Due to the extensive use of concrete structures in various applications, the improvement of their strength and quality has become of great importance. A new way of achieving this purpose is to add different types of nanoparticles to concrete admixtures. In this work, a mathematical model has been employed to analyze the vibration of concrete beams reinforced by graphene oxide (GO) nanoparticles. To verify the accuracy of the presented model, an experimental study has been conducted to compare the compressive strengths of these beams. Since GO nanoparticles are not readily dissolved in water, before producing the concrete samples, the GO nanoparticles are dispersed in the mixture by using a shaker, magnetic striker, ultrasonic devices, and finally, by means of a mechanical mixer. The sinusoidal shear deformation beam theory (SSDBT) is employed to model the concrete beams. The Mori-Tanaka model is used to determine the effective properties of the structure, including the agglomeration influences. The motion equations are calculated by applying the energy method and Hamilton's principle. The vibration frequencies of the concrete beam samples are obtained by an analytical method. Three samples containing 0.02% GO nanoparticles are made and their compressive strengths are measured and compared. There is a good agreement between our results and those of the mathematical model and other papers, with a maximum difference of 1.29% between them. The aim of this work is to investigate the effects of nanoparticle volume fraction and agglomeration and the influences of beam length and thickness on the vibration frequency of concrete structures. The results show that by adding the GO nanoparticles, the vibration frequency of the beams is increased.

• Steel and Composite Structures
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• 제48권1호
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• pp.19-25
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• 2023

Due to high application of concrete structures in construction industry, however, the quality improvement is essential. One of the new ways for this purpose is adding the nanoparticles to the concrete. In this work, vibration analysis of concrete beams reinforced by graphene oxide (GO) nanoparticles based on mathematical model has been investigated. For the accuracy of the presented model, the experimental study is done for comparing the compressive strength. Since the nanoparticles can not be solved in water without any specific process, at the first, GO nanoparticles should be dispersed in water by using shaker, magnetic striker, ultrasonic devices and finally mechanical mixer. For modelling of the strucuture, sinusoidal shear deformation beam theory (SSDBT) is utilized. Mori-Tanak model model is utilized for obtaining the effective properties of the beam including agglomeration influences. Utilizing the energy method and Hamilton's principal, the motion equations are calculated. The frequency of the concrete beam is obtanied by analytical method. Three samples with 0.02% GO nanoparticles are built and its compressive strength is compared which shows a good accuracy with maximum 1.29% difference with mathematical model and other papers. The aim of this work from the theoretical study is investigating the effects of nanoparticles volume percentage and agglomeration, length and thickness of the beam on the frequency of the structure. The results show that the with enhancing the GO nanoparticles, the frequency is increased. For example, with enhancing the volume percent of GO nanoparticles from zero to 0.08%, the compressive strength is increased 48.91%. and 46.83%, respectively for two cases of with and without agglomeration.

• 한국축산식품학회지
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• 제24권4호
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• pp.326-328
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• 2004

본 연구는 국산 배에서 단백질 분해효소를 분리, 정제하여 단백질 효소의 농도별 돈육 등심에 대한 연화 정도를 측정하여 가장 적당한 농도를 찾고자 실시하였다. 단백질 함량은 5.96 $\mu\textrm{g}$/mL와 7.25$\mu\textrm{g}$/mL을 나타냈었으나 투석한 경우는 신고가 0.19$\mu\textrm{g}$/mL, 추황이 0.24$\mu\textrm{g}$/mL를 나타내 투석할 경우 오히려 단백질 함량이 감소하였다. 투석한 단백질 분해효소를 첨가하지 않은 대조구와 각각 0.05%, 0.1% 및 0.2%를 첨가한 후 81$^{\circ}C$에서 가열한 후 냉각한 돈육 등심의 전단력은 신고에서 6.24, 5.69, 5.37 및 5.58을 추황에서 5.44, 4.92, 4.65 및 4.80을 나타냈다. 신고와 추황의 정제된 단백질 분해효소를 0.1% 첨가했을 때 가장 낮은 전단력을 보였고 첨가하지 않은 것에 비해 각각 14%와 15%의 감소를 나타냈다. 전기영동에 의한 단백질의 분자량은 약 30kDa을 나타냈다. 연도에 최대 효과를 줄 수 있는 적정함량은 0.1% 이상이라 사료된다.