• 제목/요약/키워드: aging process

검색결과 1,271건 처리시간 0.039초

Carbon Contained Ammonium Diuranate Gel Particles Preparation in Mid-process of High-temperature Gas-cooled Reactor Fuel Fabrication

  • Jeong, Kyung Chai;Cho, Moon Sung
    • Nuclear Engineering and Technology
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    • 제48권1호
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    • pp.175-181
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    • 2016
  • This study investigates the dispersibility of carbon in carbon contained ammonium diuranate (C-ADU) gel particles and the characteristics of C-ADU gel liquid droplets produced by the vibrating nozzle and integrated aging-washing-drying equipment. It was noted that the excellent stability of carbon dispersion was only observed in the C-ADU gel particle that contained carbon black named CB 10. ADU gel liquid droplets containing carbon particles with the excellent sphericity of approximately 1,950 mm were then obtained using an 80-100-Hz vibrating nozzle system. Dried C-ADU gel particles obtained by the aging-washing-drying equipment were thermal decomposed until $500^{\circ}C$ at a rate of $1^{\circ}C/min$ in an air or in 4% $H_2$ gas atmosphere. The thermally decomposed C-ADU gel particles showed 24% weight loss and a more complicated profile than that of ADU gel particles.

The Characteristic of Temperature in Ventilating Fans by Festraint or Nonrestraint (무 구속·구속 실험에 의한 환풍기 온도 특성)

  • Kim, Sung-Sam
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • 제30권1호
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    • pp.44-48
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    • 2016
  • In this paper, we analyzed the operating characteristics of a ventilating fan due to overload and overheating. The experiment assumed the forcible restraint of the blade due to external objects and the aging process. We analyzed the experimental temperature and operating characteristics of the three places in the interior of the ventilating fan. As a result of the analysis, the temperature distribution was highest to lowest in the following order: the thermal fuse, the motor inside, and the above winding. There was smell of burning enamel in the restraint experiment. Following the thermal fuse operation, the insulation of motor winding was good. In the case of rated voltage and new ventilating fan restrained for about 4hours, and the results of restraint experiments in the presence or absence of the thermal fuse, no risk of deformation or fire due to overheating was identified. Henceforward, ignition hazard experiments will be required for additional factors of aging, pollution, and defective insulation.

NMMP1, a Matrix Metalloprotease in Nicotiana benthamiana Has a Role in Protection against Bacterial Infection

  • Kang, So-Ra;Oh, Sang-Keun;Kim, Jong-Joo;Choi, Do-Il;Baek, Kwang-Hyun
    • The Plant Pathology Journal
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    • 제26권4호
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    • pp.402-408
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    • 2010
  • Plant matrix metalloproteases (MMPs) are a family of apoplastic metalloproteases closely related to human matrilysins. Up-regulation of Nicotiana benthamiana matrix metalloprotease 1 (NMMP1) expression by treatment with pathogens, ethephon and aging indicates that the gene is related to plant defense and the aging process through ethylene signaling. NMMP1 expression was higher than in normal growth leaves following infection with an incompatible pathogen Pseudomonas syringae pv. tomato T1 or a compatible pathogen P. syringae pv. tabaci and in aged leaves. Transient overexpression of NMMP1 in N. benthamiana leaves lowered the growth of P. syringae pv. tabaci. However, NMMP1-silenced leaves showed increased growth of P. syringae pv. tabaci. These data strongly suggest that NMMP1 in N. benthamiana is a defense related gene, which is positively regulated by ethylene.

Evaluation of Thermal Embrittlement Susceptibility in Cast Austenitic Stainless Steel Using Artificial Neural Network (인공신경망을 이용한 주조 스테인리스강의 열취화 민감도 평가)

  • Kim, Cheol;Park, Heung-Bae;Jin, Tae-Eun;Jeong, Ill-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • 제28권4호
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    • pp.460-466
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    • 2004
  • Cast austenitic stainless steel is used for several components, such as primary coolant piping, elbow, pump casing and valve bodies in light water reactors. These components are subject to thermal aging at the reactor operating temperature. Thermal aging results in spinodal decomposition of the delta-ferrite leading to increased strength and decreased toughness. This study shows that ferrite content can be predicted by use of the artificial neural network. The neural network has trained teaming data of chemical components and ferrite contents using backpropagation learning process. The predicted results of the ferrite content using trained neural network are in good agreement with experimental ones.

Layered model of aging concrete. General concept and one-dimensional applications

  • Truty, Andrzej;Szarlinski, Jan;Podles, Krzysztof
    • Computers and Concrete
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    • 제17권6호
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    • pp.703-721
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    • 2016
  • A novel approach to modeling concrete behavior at the stage of its maturing is presented in this paper. This approach assumes that at any point in the structure, concrete is composed of a set of layers that are activated in time layer by layer, based on amount of released heat that is produced during process of the concrete's maturing. This allows one to assume that each newly created layer has nominal stiffness moduli and tensile/compressive strengths. Hence introduction of explicit stiffness moduli and tensile/compressive strength dependencies on time, or equivalent time state parameter, is not needed. Analysis of plain concrete (PC) and reinforced concrete (RC) structures, especially massive ones, subjected to any kind of straining in their early stage of existence, mostly due to external loads but especially by thermal loading and shrinkage, is the goal of the approach. In this article a simple elasto-plastic softening model with creep is used for each layer and a general layered model behavior is illustrated on one-dimensional (1D) examples.

Exploring Social Innovation and Time Bank: Focus on the Elderly Healthcare in the Gangwon Province

  • Kim, Ho-Kyung
    • Asian Journal of Innovation and Policy
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    • 제8권2호
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    • pp.208-237
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    • 2019
  • Serious social problems related to the elderly have appeared in the Gangwon Province because the population in this area is rapidly aging. Gangwon has the highest suicide rate and the highest percentage of single households. In the process of preparing for the super-aging society, Time Bank (TB) System has been actively used in 34 countries, especially in the United States, the United Kingdom, and Japan. In Korea, the Gumi Senior Club has joined this system since 2004. TB is a multilateral exchanged system based on the philosophy that everyone's time is valued equally. Time credits are given to the person who provides social services, such as citizen participation and elderly care. People receive the desired services using time credits or donating them. If this system were applied to the Gangwon Province in accordance with its characteristics, it would help to reduce the elderly's prejudices and manage their diverse health problems. A virtual local currency using IT technologies is needed to boost the regional economy. The elderly's participation in TB is strongly needed. Future research about the effectiveness of health management is then discussed.

Preparation and Characterization of Peptizable Alumina

  • Lee, Chong-Mok;Sohn, Youn-Soo
    • Bulletin of the Korean Chemical Society
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    • 제6권6호
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    • pp.329-333
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    • 1985
  • A procedure for the preparation of peptizable pseudoboehmite has been described in detail based upon a process of neutralization of an aqueous aluminum sulfate or chloride solution with aqueous ammonia. In order to obtain peptizable pseudoboehmite products, carefully controlled conditions were required in the whole processes of neutralization, aging, washing, and drying. The optimum conditions experimentally found are the following. The aluminum salt solution is neutralized with aqueous ammonia until the final pH of the solution reaches 10.0 to 10.8 or 9.0 to 9.3 for the sulfate of chloride, respectively. The alumina gel formed is subjected to aging at $80^{\circ}C for about 3 hours and washed with water more than 5 times to reduce the residual sulfate or chloride ion in the final products to less than 4%. The pseudoboehmite gel thus obtained should be dried oven at 80 to $100^{\circ}C for a few to several hours depending on the selected temperatures.

AgingPath : Database programmed to investigate aging process

  • Park, Dae-Ui;Lee, Ji-Hyeon;Kim, Heun-Jin;Kim, Chul-Hong;Hong, Seong-Eui;Chang, Gregory-Y.;Yu, Byung-Pal;Jung, Hae-Young
    • Proceedings of the PSK Conference
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.173.1-173.1
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    • 2002
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Effects of Mustard Seed Extract on Physicochemical and Storage Characteristics of Dry-aged Pork Loin Ham

  • Han-Gyeol Cho;Hack-Youn Kim
    • Food Science of Animal Resources
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    • 제43권6호
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    • pp.961-974
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    • 2023
  • This study investigated the effects of mustard seed extracts on physicochemical and storage characteristics of dry-aged pork loin ham during the aging period. In experiment 1, antioxidant activity was assessed for mustard seed extracted with varying ethanol concentrations and the results showed high antioxidant activity at 25%, 50%, and 75% ethanol concentrations. In experiment 2, pork loin was treated with mustard seed extracts obtained using different ethanol concentrations: not treated (control), 25% (MS25), 50% (MS50), and 75% (MS75). Physicochemical and storage characteristics of pork loin ham were measured in wk 0, 2, 4, and 6. The pH, aw, CIE b*, thiobarbituric acid reactive substances and volatile basic nitrogen values were lower in treated samples compared to the control (p<0.05). In conclusion, applying mustard seed extracts, particularly MS75, in the dry-aged pork loin ham production process could enhance storage stability and improve color attributes without having negative impacts on product quality.

Effect of Anisotropy on the Wear Behavior of Age-Treated Maraging Steel Manufactured by LPBF (시효 열처리를 적용한 LPBF 제조된 마레이징 강의 마모 거동에 대한 이방성의 영향)

  • Seung On Lim;Se-Eun Shin
    • Journal of Powder Materials
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    • 제31권4호
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    • pp.308-317
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    • 2024
  • Maraging steel has excellent mechanical properties resulting from the formation of precipitates within the matrix through aging treatment. Maraging steel fabricated by the laser powder bed fusion (LPBF) process is suitable for applications including precise components and optimized design. The anisotropic characteristic, which depends on the stacking direction, affects the mechanical properties. This study aimed to analyze the influence of anisotropy on the wear behavior of maraging steel after aging treatment. The features of additive manufacturing tended to disappear after heat treatment. However, some residual cellular and dendrite structures were observed. In the wear tests, a high wear rate was observed on the building direction plane for all counter materials. This is believed to be because the oxides formed on the wear track positively affected the wear characteristics; meanwhile, the bead shape in the stacking direction surface was vulnerable to wear, leading to significant wear.