• Title/Summary/Keyword: Ageing

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Studies on the Reinforcement Treatment of Aged Hanji Using Cellulose Derivative Solutions (셀룰로오스 유도체 용액을 이용한 열화 한지의 강도보강 처리에 관한 연구)

  • Kang, Kwang-Ho;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.2
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    • pp.40-48
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    • 2011
  • To build up the conservativeness of aged paper heritages, the strength reinforcement treatment using various cellulose derivative solutions was considered. Hand-made Hanji prepared by traditional papermaking technique was firstly simulated in order to modify the overall of paper properties like aged paper heritages by accelerated ageing treatment at $150^{\circ}C$ for 24 hours, and then the ageing stability of Hanji was verified through the secondary accelerated ageing at $150^{\circ}C$ for 12 hours. The physical properties of aged Hanji were improved by applying with cellulose derivative solutions. The ageing stability for physical, optical (L, brightness, opacity, yellowness) and chemical (oxidation index, degree of polymerization) properties of aged Hanji treated with all kinds of cellulose derivative solutions was also good compared to those of untreated samples, especially using MC solution. Therefore, it was that a kind of MC solution would be well-suited for the strength reinforcement treatment of aged paper heritages.

The Changes of the Shape and Particle Size Distribution of δ' Phase on Ageing in Al-Li-( Cu, Zr) Alloys (Al-Li-( Cu, Zr) 합금에서 시효에 따른 δ' 상의 형상 및 입자크기분포의 변화)

  • Woo, K.D.;Cho, H.K.
    • Journal of the Korean Society for Heat Treatment
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    • v.7 no.2
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    • pp.96-102
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    • 1994
  • The present work was aimed to examine the changes of the shape and particle size distribution(PSD) of ${\delta}^{\prime}$ particles on ageing in Al-Li-(Cu, Zr) alloys which had low density, high specific strength and stiffness, Increasing ageing time and temperature resulted in particles whose aspect ratio tended toward 1. The aspect ratio of ${\delta}^{\prime}$ particles was not dependent upon the ageing temperature and time in Al-Li-Cu alloy but was dependent upon them in Al-Li-Zr alloy. The PSD of ${\delta}^{\prime}$ particles in Al-Li-Zr alloy skewed to the right hand compared with that in Al-Li-Cu alloy, because $Al_3Zr$ phase in Al-Li-Zr alloy formed before ageing promoted the precipitation and growth of ${\delta}^{\prime}$ phase. Therefore, the PSD of the ${\delta}^{\prime}$ particles was found to be affected by the presence of $Al_3Zr$ particles. The growth rate of ${\delta}^{\prime}$ phase was not affected by the existence of the third transition phase $T_1$ formed by the addition of Cu in Al-Li alloy but was affected by the existence of $Al_3Zr$ formed by the addition of Zr in Al-Li alloy.

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Feeding strategies and ageing time alter calpain system proteins activities and meat quality of Braford steers

  • Coria, Maria Sumampa;Pighin, Dario;Grigioni, Gabriela;Palma, Gustavo Adolfo
    • Animal Bioscience
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    • v.35 no.2
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    • pp.272-280
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    • 2022
  • Objective: The aim of this study was to evaluate the effect of ageing and feeding strategies on the calpain protease system and meat quality traits in Braford steers. Methods: Thirty Braford steers were employed; 15 animals were supplemented with corn silage during finishing and 15 were kept only on pasture. Meat quality traits and calpain system protein activity were evaluated in longissimus thoracis et lumborum (LTL) steaks aged for 2, 7, 14, and 21 days. Results: Aged meat showed higher pH and calcium content, while Warner Bratzler shear force (WBSF) decreased to day 21. No interaction between ageing and diet was seen for quality traits. Steers finished with corn silage showed higher values of water holding capacity, WBSF and free calcium, and lower values of pH and cooking loss. Calpain and calpastatin activities decreased with ageing. Finishing steers on pasture produced higher values of calpains and lower values of calpastatin activities. The higher values of calpain 1 activity were observed in muscles aged 2 days from pasture finished animals, and the lower activity of the inhibitor in the 21 days aged samples of the same group. Conclusion: These results suggest a diet by ageing interaction in calpains and calpastatin and this interaction impact in Warner Bratzler Shear Force in Braford LTL muscle.

A parametric investigation on seismic performance of ageing Sarıyar dam

  • Ahmad Yamin Rasa;Ahmet Budak
    • Structural Engineering and Mechanics
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    • v.91 no.2
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    • pp.123-133
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    • 2024
  • The assessment of seismic behavior and seismic performance of ageing Sarıyar concrete gravity dam constructed on Sakarya River in Türkiye is the main focus of this paper. For this purpose, the impact of sediment domain, ageing of concrete material under the impact of chemical and mechanical actions, and dam-water-sediment interaction are included in the two-dimensional (2D) finite element (FE) model developed in FORTRAN 90 environment. In the FE model, the dam and age dependent sediment domains are modeled by solid elements, while reservoir domain is modeled by Lagrangian fluid elements. The radiation of reflected waves to the unbounded water domain is modeled by infinite Lagrangian fluid elements, while unbounded sediment domain is modeled by infinite solid elements. The coupled system was assumed to be under the simultaneous impact of Vertical (V) and Horizontal (H) ingredients of 1976 Koyna earthquake and the coupled system was analyzed in Laplace domain by direct method. Due to the deterioration of the concrete, the H and V displacement responses together with the fundamental period of the body, elongate throughout the lifetime and this reduce the seismic safety of the dam. It was deduced that the ageing dam body will not experience major damages under the Koyna earthquake both at the earlier and later ages. Furthermore, at the heel of the dam, the hydrodynamic pressure responses are decreased by rising the sediment domain depth.

Effect of Ageing Temperature and Time on the Meat Quality of Longissimus Muscle from Hanwoo Steer (숙성온도와 기간이 한우 거세우 배최장근의 육질 특성에 미치는 영향)

  • Kim, Jin-Hyoung;Cho, Soo-Hyun;Seong, Pil-Nam;Hah, Kyung-Hee;Kim, Hak-Kyun;Park, Beom-Young;Lee, Jong-Moon;Kim, Dong-Hun;Ahn, Chong-Nam
    • Food Science of Animal Resources
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    • v.27 no.2
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    • pp.171-178
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    • 2007
  • This study was conducted to investigate the effect of ageing temperature(0 and $4^{\circ}C$) and time(2, 7, 14, 21, 28, and 49 days) on the meat quality of longissimus muscle from Hanwoo steer. The pH, Warner-Bratzler shear force(WBSF), myofibrillar fragmentation index(MFI), cooking and purge loss, sensory, morphological changes, and amino acid composition were assessed. The pH of longissimus muscle increased significantly(p<0.05) for 21 days at $0^{\circ}C$ and 14 days at $4^{\circ}C$, but decreased thereafter. Longissimus muscle aged from 14 days to 28 days at $4^{\circ}C$ had a lower WBSF than longissimus muscle aged at $0^{\circ}C$(p<0.05). The WBSF of longissimus muscle decreased significantly(p<0.05) with ageing time. The MFI, cooking and purge loss, tenderness, and juiciness scores were higher for longissimus muscle aged at $4^{\circ}C$ than at $0^{\circ}C$. As ageing time increased, the MFI, cooking and purge loss, tenderness, juiciness, and amino acid composition of longissimus muscle increased significantly(p<0.05) with ageing at 0 or $4^{\circ}C$. Transmission electron microscopy showed Z-disk degradation and morphological changes of the myofibrils correlating with increased tenderness during the ageing time. Based on these results, the proper ageing conditions of longissimus muscle of Hanwoo steer were 14 days of ageing at $0^{\circ}C$ or 7 days of ageing at $4^{\circ}C$. However, further study on the application of ageing technology to this industry is necessary for the optimization of ageing conditions for the sub-primals or muscles from Hanwoo beef.

Simulation of Interface Ageing Effect of Suspension Insulator Using ANSYS (ANSYS를 이용한 현수애자의 계면팽창거동에 따른 특성 평가)

  • 우병철;한세원;조한구
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.8
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    • pp.342-347
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    • 2003
  • The suspension insulators are subjected to harsh environment in service for a long time. Long term reliability of the insulators is required for both mechanical and electrical performances. We studied an analysing method to find out a deformation of brittle porcelain with a thermal expansion of simulation analysis and experimental results show that cement volume growths affect severely to b mechanical failure ageing.

Selective Chemical Wet Etching of Si0.8Ge0.2/Si Multilayer

  • Kil, Yeon-Ho;Yang, Jong-Han;Kang, Sukil;Jeong, Tae Soo;Kim, Taek Sung;Shim, Kyu-Hwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.6
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    • pp.668-675
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    • 2013
  • We investigate the effect of the ageing time and etching time on the etching rate of SiGe mixed etching solution, namely 1 vp HF (6%), 2 vp $H_2O_2$ (30%) and 3 vp $CH_3COOH$ (99.8%). For this etching solution, we found that the etch rate of SiGe layer is saturated after the ageing time of 72 hours, and the selectivity of $Si_{0.8}Ge_{0.2}$ layer and Si layer is 20:1 at ageing time of 72 hours. The collapse was appeared at the etching time of 9min with etching solution of after saturation ageing time.

Anti-ageing Effects of Cysteine-containing Peptides Derived from Milk Whey Protein

  • Dudek, Steffi;Clark, David C.
    • Journal of Dairy Science and Biotechnology
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    • v.23 no.2
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    • pp.107-114
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    • 2005
  • The trend towards ageing populations has been observed over many years in Europe and the US but has accelerated significantly in developed countries in Asia including Japan and South Korea. In the latter country the elderly population (65+) has increased 5-fold between 1960 and 2000 and this group will comprise 40% of the population by 2050. This creates a new socio-economic group with specific demands and considerable spending power. As ageing occurs a range of changes occur in the body that can be moderated by adjustments in nutrition. A significant body of evidence points to changes in the balance of glutathione synthesis and utilisation as people age. Glutathione is tile most important natural anti-oxidant of the body and the amounts present can become limited by available cysteine in the diet. A cysteine-enriched peptide product, Cysteine Peption$^{TM}$ has been developed by DMV International for dietary supplement and food applications. A qualitative consumer trial has indicated benefits including improved sleep and more energy. Animal and clinical trial will be described that provide indications on bioavailability and possible mechanisms of action of Cysteine Peption$^{TM}$ with particular focus on the ageing population.

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Ageing Diagnostics in Oil Transformer for Large Capacity due to Test methods (시험방법에 의한 대용량 유입변압기의 열화진단)

  • Sim, Yoon-Tae;Kim, Wang-Gon;Hong, Jin-Woong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.96-99
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    • 2003
  • In this paper, ageing diagnostics in the large capacity oil transformer are investigated. Following items are investigated for the ageing diagnostic in transformer oils (leakage current of sensor, power consumption and temperature of transformer oil). All temperature data are gathered from daily report in the substation. The power consumption of transformer are gathered output report of APIS(Airport Power Information System). Especially, data of sensor leakage current are accumulated from the online diagnostic system for transformer oil. The temperature of transformer oils major change factor was ambient temperature and capacity of power load. The leakage current are change by oil temperature. The leakage current ware not more than 2 [nA] in summer,

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