• 제목/요약/키워드: thermal activation

검색결과 779건 처리시간 0.028초

Ginsenoside Rg5 prevents apoptosis by modulating heme-oxygenase-1/nuclear factor E2-related factor 2 signaling and alters the expression of cognitive impairment-associated genes in thermal stress-exposed HT22 cells

  • Choi, Seo-Yun;Kim, Kui-Jin;Song, Ji-Hyeon;Lee, Boo-Yong
    • Journal of Ginseng Research
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    • 제42권2호
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    • pp.225-228
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    • 2018
  • Our results suggested that thermal stress can lead to activation of hippocampal cell damage and reduction of memory-associated molecules in HT22 cells. These findings also provide a part of molecular rationale for the role of ginsenoside Rg5 as a potent cognitive impairment preventive compound in blocking the initiation of hippocampal damage.

Low Writing Field on Perpendicular Nano-ferromagnetic

  • Wibowo, Nur Aji;Rondonuwu, Ferdy S.;Purnama, Budi
    • Journal of Magnetics
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    • 제19권3호
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    • pp.237-240
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    • 2014
  • For heat-assisted magnetic recording, magnetization reversal probabilities of nano-Pt/MnSb multilayer film with perpendicular magnetic anisotropy under thermal pulse activation were investigated numerically by solving the Landau-Lifshift Gilbert Equation. Magnetic parameters of nano-Pt/MnSb multilayer were used with anisotropy energy of $3{\times}10^5$ erg/cc and saturation magnetization of 2100 G, which offer more than 10 y data stability at room temperature. Scheme of driven magnetic field and thermal pulse on writing mechanism was designed closely to real experiment. This study found that the chosen material is potential to be used as a high density magnetic storage that requires low writing field less than two-hundreds Oersted through definite heating and cooling interval. The possibility of writing data with a zero driven magnetic field also became an important result. Further study is recommended on the thickness of media and thermal pulse design as the essential parameters of the reversal magnetization.

수소용기내에서 수소저장합금 분말 성형체의 수소 흡수 및 방출 거동 (Hydrogen Absorption and Desorption Behaviors of Hydrogen Storage Alloy Powder Compacts in Hydride Cylinder)

  • 김찬중;이재명;김대룡
    • 한국수소및신에너지학회논문집
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    • 제6권1호
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    • pp.43-52
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    • 1995
  • Hydrogen storage alloy powder compacts were prepared by using automatic press, with PTFE as a binder. Hydrogen absorption and desorption characteristics and thermal conducting property of the compacts were studied using test hydrogen cylinder, comparing with bare alloy powder. The compacts showed better rate capability and activation characteristics than bare powder. Effective thermal conductivity and diffusivity of the compact bed were $1.0{\times}10^{-2}W/cmK$ and $2.0{\times}10^{-2}cm^2/S$, respectively, which were similar to that of bare powder bed. A good rate capability of the compacts was interpreted in terms of hydrogen permeation rather than thermal conductivity in the beds.

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고전압용 에폭시 수지계 전기절연재료의 열분해 속도론 (Thermal Decomposition Kinetics of Epoxy Resin System for High Voltage Electrical Insulator)

  • 안현수;심미자;김상욱
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.345-347
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    • 1997
  • The thermal decomposition kinetics of epoxy resin system as an electrical insulator for high voltage was investigated by using thermogravimetric analysis and Horowitz & Metzger equation. Epoxy resin system was degraded by one stage. The thermal decomposition activation energies of epoxy resin systems were all about 380 kJ/mol at the GN contents of 0 and 5 phr, and it abruptly decreased at 10 phr.

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실리콘에 MaV로 이온주입된 인의 결함분포와 profile에 관한 연구 (A Study of defect distribution and profiles of MeV implanted phosphorus in silicon)

  • 정원채
    • E2M - 전기 전자와 첨단 소재
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    • 제10권9호
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    • pp.881-888
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    • 1997
  • This study demonstrats the profiles of phosphorus ions in silicon by MeV implantation(1∼3 MeV). Implanted profiles could be measured by SIMS(Cameca 4f) and compared with simulation results(TRIM program and analytical description method only using on Pearson function). The experimental result in the peak concentration region has a little bit deviation from simulation data. By RBS and Channeling measurements the defect distribution of implanted samples could be measured and spectrum are calibrated depth with RUMP simulation By XTEM measurement the thickness of defect zone also could be measured. Finally thermal annealing for the electrical activation of implanted ions carried out by RTA(rapid thermal annealing). The concentration-depth profiles after heat treatment was measured by SR(spreading resistance)-method.

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Epoxy-siloxane IPN의 열적 안정성에 미치는 후기경화의 영향 (Effects of Post-curing on Thermal Stability of Epoxy-sioxane IPN Structure)

  • 조영신;심미자;김상욱
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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    • pp.944-946
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    • 1999
  • The thermal stability of the post cured epoxy-polysiloxane IPN structure was observed by using DSC and TGA. As the post curing time increased the glass transition temperature increased and the secondary exothermic peak disappeared. The thermally decomposing activation energy calculated by using Kissinger expression was 225.6 kJ/mol. The thermal stability of the grafted IPN of epoxy and silicon compound depends on the composing ratio and post curing conditions of time and temperature.

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Al-Mg-(Ca) 합금에서 결정립의 열적 안정성 (Thermal Stability of Grains in Al-Mg-(Ca) Alloys)

  • 전중환
    • 열처리공학회지
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    • 제25권4호
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    • pp.175-180
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    • 2012
  • Role of Ca in grain growth behavior has been investigated in hot-rolled Al-3%Mg and Al-3%Mg-0.5%Ca wrought alloys. When annealed for 1 hr from 723 to 823 K, grain size of the Al-3%Mg alloy increased rapidly above 723 K, whereas grains were relatively stable up to 773 K for the Ca-containing alloy. Grain homogeneity of the Ca-containing alloy was better than that of the Ca-free alloy both in hot-rolled and annealed states. Calculated activation energies for grain growth were 77.6 and 85.9 kJ/mole in the range of 723 to 823 K for the alloys with 0 and 0.5%Ca, respectively. Taking SEM images and EDS results into account, enhanced thermal stability in response to Ca addition would be associated with Al4Ca compounds located along the grain boundaries, which eventually play a role in restricting grain growth at elevated temperatures.

Field Enhanced Rapid Thermal Process for Low Temperature Poly-Si TFTs Fabrications

  • Kim, Hyoung-June;Shin, Dong-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.665-667
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    • 2005
  • VIATRON TECHNOLOGIES has developed FE-RTP system that enables LTPS LCD and AMOLED manufacturers to produce poly-Si films at low cost, high throughput, and high yield. The system employs sequential heat treatment methods using temperature control and rapid thermal processor modules. The temperature control modules provide exceptionally uniform heating and cooling of the glass substrates to within ${\pm}2^a\;C$. The rapid thermal process that combines heating with field induction accelerates the treatment rates. The new FE-RTP system can process $730{\times}920mm$ glass substrates as thin as 0.4 mm. The uniform nature of poly-Si films produced by FE-RTP resulted in AMOLED panels with no laser-Muras. Furthermore, FE-RTP system also showed superior performances in other heat treatment processes involved in poly-Si TFT fabrications, such as dopant activation, gate oxide densification, hydrogenation, and pre-compaction.

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급속 열처리 공정에 의한 다결정 실리콘 박막의 전기적, 구조적 특성 연구 (Effects of the Rapid Thermal Annealing on the Electrical and Structural Properties of Polysilicon Films)

  • 김윤태;유형준;전치훈;장원익;김상호
    • 대한전자공학회논문지
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    • 제25권9호
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    • pp.1060-1067
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    • 1988
  • In this paper, we have investigated the effects of rapid thermal process on the electrical and structural properties of silicon films. It was shown that required times and temperature for the successful activation of dopants (Boron, Phosphorus:5E15atoms/cm\ulcorner were above 1000\ulcorner, 10sec, respectively. The typical resistivities of films deposited below 600\ulcorner were in the range of 1.0 E-3ohm-cm which was 20-30% lower than that of initially polycrystalline silicon depositd above 600\ulcorner. After rapid thermal process at high temperature above 1000\ulcorner, the films did not reveal any change in resistivity due to the dopant segregation, and better electrical conductivity could be obtained by increasing the process time. The grain growth by RTA treatment was more salient in the case of the doped amorphous than that of initially polycrystalline. The surface of the films also preserved the higher structural perfection and surface smoothness.

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Metal Complexes of Enrofloxacin Part I: Preparation, Spectroscopic, Thermal Analyses Studies and Antimicrobial Evaluation

  • El-Shwiniy, Walaa H.;El-Attar, Mohamed S.;Sadeek, Sadeek A.
    • 대한화학회지
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    • 제57권1호
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    • pp.52-62
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    • 2013
  • The interaction of titanium (IV), yttrium (III), zirconium (IV), palladium (II) and cerium (IV) with deprotonated enrofloxacin leads to the formation of the neutral or cationic mononuclear complexes. The isolated solid complexes have been characterized with physicochemical and spectroscopic techniques and thermogravimeteric analyses. The spectroscopic data indicate that the enrofloxacin ligand is on the deprotonated mode acting as bidentate ligand coordinated to the metal ions through the ketone oxygen and a carboxylato oxygen and the metal ions completed the coordination number with water molecules. The thermal decomposition mechanisms proposed for enrofloxacin and their metal complexes were discussed. The activation energies, $E^*$, enthalpies, ${\Delta}H^*$, entropies, ${\Delta}S^*$ and Gibbs free energies, ${\Delta}G^*$, of the thermal decomposition reactions have been derived from thermogravimetric (TG) and differential thermogravimetric (DTG) curves, using Coats-Redfern (CR) and Horowitz-Metzeger (HM) methods. The antimicrobial activity has been evaluated against six different microorganisms.