• Title/Summary/Keyword: cell wall materials

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A Study on the Radiation Shielding Analysis for Reinforcing the Hot Cell Regular Concrete Shield Wall (핫셀의 일반 콘크리트 보강을 위한 방사선 차폐해석 연구)

  • 조일제;황용화
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.985-990
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    • 2003
  • In order to demonstrate Advanced Spent Fuel Conditioning Process (ACP), shielding facilities such as hot cell suitable to handling radionuclides and process property will be necessary. But the construction of new facilities needs much money, man-power and time, it is now scheduled to remodel the hot cell, which has already been installed and maintained at Irradiated Material Experiment Facility (IMEF) in the Korea Atomic Energy Research Institute (KAERI). The basic structure and concrete shield wall of hot cell partly have been constructed on the base floor in IMEF building in current status. And hot cell after remodeling will be used for carrying out the lab-scale experiment of ACP. The hot cell was built in accordance with 35 curies of fe-59(1.2 MeV) as design criteria of radiation dose limit. But the radioactive source of ACP is expected to be much higher than design criteria of IMEF, shielding ability of the hot cell in the current status is unsatisfactory to the hot test of ACP. Therefore shield wall shall be reinforced with heavy concrete, steel or lead. In this paper, dose rates are calculated according to ACP source, shielding materials, etc., and reinforcement structures are determined considering the current situation of hot cells, installation of shield windows and the easiness of work.

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Defense-Related Responses in Fruit of the Nonhost Chili Pepper against Xanthomonas axonopodis pv. glycines Infection

  • Chang, Sung Pae;Jeon, Yong Ho;Kim, Young Ho
    • The Plant Pathology Journal
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    • v.32 no.4
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    • pp.311-320
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    • 2016
  • Xanthomonas axonopodis pv. glycines (Xag) is a necrotrophic bacterial pathogen of the soybean that causes bacterial pustules and is a nonhost pathogen of the chili pepper. In the current study, chili pepper fruit wound inoculated in planta with Xag 8ra formed necrotic lesions on the fruit surface and induced several structural and chemical barriers systemically in the fruit tissue. The initial defense response included programmed cell death of necrotizing and necrotized cells, which was characterized by nuclear DNA cleavage, as detected by TUNEL-confocal laser scanning microscopy (CLSM), and phosphatidylserine exposure on cell walls distal to the infection site, as detected by Annexin V FLUOS-CLSM. These two responses may facilitate cell killing and enhance transportation of cell wall materials used for cell wall thickening, respectively. The cells beneath the necrotic tissue were enlarged and divided to form periclinal cell walls, resulting in extensive formation of several parallel boundary layers at the later stages of infection, accompanying the deposition of wall fortification materials for strengthening structural defenses. These results suggest that nonhost resistance of chili pepper fruit against the nonhost necrotrophic pathogen Xag 8ra is activated systematically from the initial infection until termination of the infection cycle, resulting in complete inhibition of bacterial pathogenesis by utilizing organspecific in situ physiological events governed by the expression of genes in the plant fruit organ.

A study on the Optimum Design Configuration of Passive Solar TI-wall system (투명단열재가 적용된 축열벽 시스템의 최적구성 선정에 관한 연구)

  • Kim, Byoung-Soo;Yoon, Jong-Ho;Yoon, Yong-Jin;Baek, Nam-Choon
    • KIEAE Journal
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    • v.3 no.2
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    • pp.37-44
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    • 2003
  • The aim of this study was to analyze the thermal performance through Test-Cell of TI-wall in domestic climate. This study was carried out as follows: 1) The TI-wall was studied for ability to reduce heat loss through the building envelope and analyzed to TIM properties. 2) Test models of TI-wall were designed through the investigation of previous paper and work, measured for winter and spring, and the thermal effects were analyzed. The type of the TIM used in test model is small-celled(diameter 4mm and thickness 50mm) capillary and cement brick(density $1500kg/m^3$) was used by thermal mass. 3) Test-cell of TI-wall was calibrated from measured data and the dynamic simulation program ESP-r 9.0. In these simulations, the measured climate conditions of TaeJon were used as outdoor conditions, and the simulation model of Test-cell was developed. 4) The sensitivity analysis is executed in various aspects with standard weather files and ESP-r 9.0, and then most suitable system of TI-wall are predicted. Finally, The suitable system of TI-wall was analysed according to sizes of air gap, kinds, thickness, and the surface absorption of therm wall. The result is following. In TI-wall, Concrete is better than cement brick, at that time the surface absorption is 95%, and the most efficient thickness is 250mm. As smaller of a air gap, as reducer of convection heat loss, it is efficient for heating energy. However, ensuring of a air gap at least more than 50mm is desirable for natural ventilation in Summer.

Characteristics of Water Soluble Fractions of Wheat Bran Treated with Various Thermal Processes (열처리 밀기울의 수용성 분획의 특징)

  • Hwang, Jae-Kwan;Kim, Chong-Tai;Cho, Sung-Ja;Kim, Chul-Jin
    • Korean Journal of Food Science and Technology
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    • v.27 no.6
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    • pp.934-938
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    • 1995
  • Water soluble fractions (WSF) of wheat bran treated with thermal processes such as autoclaving, microwaving and extrusion were characterized to investigate the structural response of plant cell wall to thermal and mechanical energy. From the chemical analysis and gel filtration chromatography of WSF, gelatinization of starch was found to be the primary solubilizing mechanism of wheat bran, followed by the structural disintegration of fibrous non-starch cell wall materials. It was also found that extrusion process resulted in degrading relatively higher molecular weight non-starch polysaccharides from the cell wall. GC analysis of water soluble non-starch polysaccharides indicates that the arabinoxylan residues of cell wall are the most susceptible site to thermal treatments studied. In particular, the degrading degree of cell wall of wheat bran is the most significant for extrusion accompanying both high temperature and high shear.

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Value of Porous Titanium Alloy Plates for Chest Wall Reconstruction after Resection of Chest Wall Tumors

  • Qi, Yu;Li, Xin;Zhao, Song;Han, Yong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4535-4538
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    • 2014
  • Objective: To explore the value of porous titanium alloy plates for chest wall reconstruction after resection of chest wall tumors. Materials and Methods: A total of 8 patients with chest wall tumors admitted in our hospital from Jan. 2006 to Jan. 2009 were selected and underwent tumor resection, then chest wall repair and reconstruction with porous titanium alloy plates for massive chest wall defects. Results: All patients completed surgery successfully with tumor resection-induced chest wall defects being $6.5{\times}7cm{\sim}12{\times}15.5$ cm in size. Two weeks after chest wall reconstruction, only 1 patient had subcutaneous fluidify which healed itself after pressure bandaging following fluid drainage. Postoperative pathological reports showed 2 patients with costicartilage tumors, 1 with squamous cell carcinoma of lung, 1 with lung adeno-carcinoma, 1 with malignant lymphoma of chest wall, 2 with chest wall metastasis of breast cancers and 1 with chest wall neurofibrosarcoma. All patients had more than 2~5 years of follow-up, during which time 1 patient with breast cancer had surgical treatment due to local recurrence after 7 months and none had chest wall reconstruction associated complications. The mean survival time of patients with malignant tumors was ($37.3{\pm}5.67$) months. Conclusions: Porous titanium alloy plates are safe and effective in the chest wall reconstruction after resection of chest tumors.

Photocurrent Improvement by Incorporation of Single-Wall Carbon Nanotubes in TiO2 Film of Dye-Sensitized Solar Cells

  • Jung, Kyoung-Hwa;Jang, Song-Rim;Vittal, R.;Kim, Dong-Hwan;Kim, Kang-Jin
    • Bulletin of the Korean Chemical Society
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    • v.24 no.10
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    • pp.1501-1504
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    • 2003
  • Single-wall carbon nanotubes (SWCN) were integrated in $TiO_2$ film and the beneficial influence on the dyesensitized solar cells in terms of improved photocurrent was studied in the light of static J-V characteristics obtained both under illumination and in the dark, photocurrent transients, IPCE spectra and impedance spectra. Compared with a solar cell without SWCN, it is established that the photocurrent density of the modified cell increases at all applied potentials. The enhanced photocurrent density is correlated with the augmented concentration of electrons in the conduction band of $TiO_2$ and with increased electrical conductivity. Explanations are additionally corroborated with the help of SEM, Raman spectra and dye-desorption measurements.

Thermal Performance Evaluation Monitoring Study of Transparent Insulation Wall System (투명단열 축열벽 시스템의 열성능 평가 실험 연구)

  • Kim, B.S.;Yoon, J.H.;Yoon, Y.J.;Baek, N.C.;Lee, J.S.
    • Journal of the Korean Solar Energy Society
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    • v.23 no.1
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    • pp.1-8
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    • 2003
  • Various efforts to combine new high-tech materials with solar system have been progressed nowadays in order to improve the performance of the existing passive solar system. TIM(Transparent Insulation Material) replacing the conventional outer building envelope glazing as well as the wall is good example for this trend. TI integrated wall is a thermal mass wall with a special shaped TIM instead of using typical envelope materials The tested TIM type is a small(diameter 4mm and thickness 50mm) capillary tube of Okalux model and cement brick(density 1500kg/m3). The purpose of this study was to analyze the thermal performance through the actual measurements performed in a test cell. This study was carried out to justify the following issues. 1) the impact of Tl-wall over the temperature variations 2) the impact of mass wall surface absorptance over the transient thermal behavior and 3) the impact of thermal mass wall thickness over the temperature variations. Finally, as results indicated that the peak time of room temperature was shifted about one hour early when absorptance of thermal mass wall changed from 60% to 95% for the 190mm thickness thermal mass wall test case. the temperature difference of both surfaces of thermal mass wall surface showed about $23^{\circ}C$ during a day of March for the 380mm thickness thermal mass wall case. However, the thermal mass wall was over-heated by outside temperature and solar radiation in a day of May the temperature difference of both surfaces of thermal mass wall surface was indicated $10^{\circ}C$ and inside temperature was observed more than average 22C.

Slab Thickness Calculations on Hot Cell

  • Ha, Yung-Joon;Kim, Seong-Yun;Kim, Dong-Hoon
    • Nuclear Engineering and Technology
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    • v.10 no.1
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    • pp.26-36
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    • 1978
  • Numerical computations of radioactivities and decay energies in a spent fuel have been carried out for designing of a hot cell. Optimum wall and window thicknesses that can preserve spent fuel rods for experimental purposes are estimated with burnup rate of 33,000 MWD/T(U) which is nearly maximum from a pressurized water reactor such as the Go-Ri Unit 1. Before putting the spent fuels into a hot cell, it is assumed for thickness estimates of shield materials that they are cooled in a storage tay for several lime intervals. Considered are various types of shield materials through which changing the distances from a source to an observation point is also made.

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Chemical and micromorphological changes of archaeological waterlogged wood degraded in marine situations. (해양에서 열화된 완도선 수침고목재의 화학적.미시형태적 변화)

  • Kim, Ik-Joo
    • 보존과학연구
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    • s.11
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    • pp.87-105
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    • 1990
  • Chemical and micro morphological changes of archaeological waterlogged woods from shipwrecked materials in marine situations were investigated which were submerged in seabed for over 900 years. Tested Wood species were Pinusdensiflora, Zelkova serrata, Quercus acutissima and Camellia japonica. The obtained results were summarized as follows; Chemical analysis showed that lignin content was increased, whereas the amout of holocellulose was heavily decreased in the degraded archaeological lwoods(DAW), when compared to the recent woods. The amount of alkalineextractives in the DAW was extremley high. IR spectra showed that disappearance of absortion band at $1,730㎝^-1$ intensity increase at 1,600, 1,500 and $1,270㎝^-1$ and the emergence of single band around $1,050㎝^-1$.Microscopic investigation showed that cell wall of latewood tracheids and fiber in the DAW were severely degraded while, early wood tracheids less degraded. Degradation in the cell wall was mainley occurred in $S_2$layer, while the middle lamella was the least degraded. The micro morphological characteristics of DAW were separation of secondary wall from middle lamella, cavities aligned with micro fibril angle in $S_2$layer and granular appearance of secondary wall by the bacterial attack.

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A Simple Beam Model for Thin-Walled Composite Blades with Closed, Two-Cell Sections (폐쇄형 이중세포로 된 박벽 복합재료 블레이드의 단순화 해석 모델)

  • Jung, Sung-Nam;Park, Il-Ju;Lee, Ju-Young;Lee, Jung-Jin
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2005.04a
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    • pp.187-190
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    • 2005
  • A simple beam model based on a mixed method is proposed for the analysis of thin-walled composite blades with a two-cell airfoil section. A semi-complementary energy functional is used to obtain the beam force-displacement relations. The theory accounts for the effects of elastic couplings, shell wall thickness, warping, and warping restraint. All the kinematic relations as well as the cross-section stiffnesses are evaluated in a closed-form through the current beam formulation. The theory has been applied to two-cell composite blades with extension-torsion couplings and fairly good correlation has been observed in comparison with a detailed analysis and other literature.

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