• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.13.1-16
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• 2003

There is no study that application of the maturity using H.S.C and H.S.C. Also activation energy has different values according to the cement, admixture and water-cement ratio. Therefore to make accurate explanation for the effect of temperature on concrete strength development properties, it is necessary that activation energy value according to the kind of cement is reviewed. This study compares and estimates equivalent age using activation energy value obtained by this experiment and Freiesleben activation energy value with compressive strength of concrete. As the result of this study, activation energy value obtained by this study has more accurate explanation of temperature's influence on concrete strength development than Freiesleben activation energy value.

• 공업화학
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• 제28권6호
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• pp.649-654
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• 2017

제주도에서 다량 발생하고 있는 폐감귤박을 활성화제로 KOH를 사용하여 활성탄을 제조하였고, 제조된 활성탄의 특성을 검토하였다. KOH 침적비율(100~300%), 활성화 온도($400{\sim}900^{\circ}C$) 및 활성화 시간(0.5~1.5 h)의 조건에서 각 조건이 증가할수록 요오드 흡착능은 증가하였으나 활성탄의 수율은 감소하였다. 그리고 활성화 시간의 경우 1.5 h 이상에서는 요오드 흡착능 및 활성탄 수율에서 비슷하였다. 또한 KOH 침적비율이 증가할수록 비표면적 및 세공부피는 증가하였으나 세공크기는 감소하였으며, 제조된 평균 세공크기는 $20{\sim}25{\AA}$이었다. KOH의 침적비율 300%, 활성화 온도 $900^{\circ}C$, 활성화 시간 1.5 h에서 제조된 활성탄은 비표면적 및 요오드 흡착능이 각각 $1,527m^2/g$ 및 1,246 mg/g으로 가장 높았다.

• 소성∙가공
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• 제19권7호
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• pp.416-422
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• 2010

The $\{10\bar{1}2\}$ twinning characteristics, such as active twin variants, volume fraction of twins with strain, twin morphology, twin texture and angle relationship between twins, were dependent on the activation mode (i.e., tension parallel to the caxis or compression perpendicular to the c-axis). The selection criterion of active twin variants was governed by the Schmid law. This activation of selected twin variants depending on the activation mode consequently caused a totally different plastic deformation behavior in two activation modes. The differences in the deformation characteristics, such as flow stress and work hardening rate, between both activation modes were explained in relation with activation stresses for slips and twinning, relative activities of twinning and slips during plastic deformation, grain refining effect by twin boundaries (Hall-Petch effect), and twinning-induced change in activities of slips.

• 한국수소및신에너지학회논문집
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• 제9권3호
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• pp.127-133
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• 1998

각각 다른 기판온도에서 진공 증착법으로 제작된 Pd 박막들의(두께 ) 수소 흡수-방출 동역학을 실험하였다. 상, 온도영역에서 수소기체를 흡수-방출 시키면서 정방향과 역방향 활성화에너지를 구하고 반응엔탈피를 구하였다. 기판의 온도가 상온인 시료는 정반응 활성화에너지가 kcal/mol H이고 역방향은 kcal/mol H 반응엔탈피는 -2kcal/mol H였다. 기판의 온도가 인 시료는 정방향 활성화에너지 kcal/mol H 이고 역방향 활성화에너지 kcal/mol H였다. 기판의 온도가 상온인 시료의 구조적 치밀성, 온도변화에 따른 비저항 값의 변화율 등을 측정해 보았을 때 기판의 온도가 상온인 시료에 비하여 더 안정된 상태였지만 활성화 에너지의 오차값이 크게 얻어졌다.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.62-62
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• 2003

This study was carried out to investigate the effects of activation agents on parthenogenetic activation of pig oocytes matured in vitro. The medium used for oocyte maturation was tissue culture medium (TCM) 199 supplemented with 26.19 mM sodium bicarbonate, 0.9 mM sodium pyruvate, 10 $\mu\textrm{g}$/ml insulin, 2 $\mu\textrm{g}$/ml vitamin $B_{l2}$, 25 mM Hepes, 10 $\mu\textrm{g}$/ml bovine apotransferrin, 150 $\mu$M cysteamine, 10 IU/ml PMSG, 10 IU/ml hCG, 10 ng/ml EGF, 0.4% BSA, 75 $\mu\textrm{g}$/ml sodium penicillin G, 50 $\mu\textrm{g}$/ml streptomycin sulfate and 10% pFF. After about 22 h of culture, oocytes were cultured without cysteamine and hormones for 22 h at 38.5$^{\circ}C$, 5% $CO_2$ in air. Cumulus-free oocytes involving first polar body were activated by exposure to various concentrations of ethanol and exposure time of ethanol in Hepes-buffered NCSU23 medium. Also, oocytes were activated by electric pulse alone or combination with ethanol. For electrical activation, oocytes were rinsed twice in 0.3 M mannitol solution supplemented with 0.1 mM CaC1$_2$, 0.2 mM MgC1$_2$, 0.5 mM Hopes and 0.01% BSA, and transferred to a chamber consisting of two electrodes 1 mm apart which was overlaid with the same activation solution. Oocytes were activated with a single DC pulse of 1.3 ㎸/cm for 30 $\mu$sec. After activation treatments, oocytes were washed three times with Hepes-buffered NCSU23 medium and were washed twice with NCSU23 culture medium containing 0.4% BSA, and then cultured in 500 ${mu}ell$ of the same medium for 20 h at 38.5$^{\circ}C$, 5% $CO_2$ in air. The activation rates of oocytes were higher in 6, 7 and 8% ethanol concentrations compared with 0, 5, 9 and 10% ethanol concentrations. Significantly more oocytes (29.3~33.7%) were activated in the exposure for 8, 10, 12 and 15 min than those in the exposure for 0 and 5 min, but there was no difference due to exposure to 8% ethanol for 8 to 15 min. Electric pulse treatment followed by exposure to ethanol significantly improved the rate of oocyte activation (61.9%) compared with that of other 3 treatments. In conclusion, the optimal activation treatment of ethanol exposure alone for the in-vitro matured pig oocytes was 8% ethanol for 8 to 15 min. Electric pulse treatment followed by ethanol exposure significantly improved the rate of activation.n.

• BMB Reports
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• 제34권6호
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• pp.517-525
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• 2001

Six renaturable protein kinases that utilize the myelin basic protein (MBP) as a substrate were activated during prolonged exposure of cardiac myocytes to okadaic acid (OA). We characterized the substrate preference and activation of these kinases, with particular emphasis on 3 novel kinases-MBPK-55, MBPK-62 and MBPK-87. The transcription factors c-Jun, Elk, ATF2, and c-Fos that are used to assess mitogen-activated protein kinase activation were all poor substrates for these three kinases. MAPKAPK2 was also not phosphorylated. In contrast, Histone IIIS was phosphorylated by MBPK-55 and MBPK-62. These protein kinases were activated in cultured cardiac fibroblasts, H9c2 cardiac myoblasts, and Cos cells. High concentrations (0.5 to $1\;{\mu}M$) of OA were essential for the activation of the protein kinases in all of the cell types examined, whereas calyculin A [an inhibitor of protein phosphatase 1 (PP1) and PP2A], cyclosporin A (a PP2B inhibitor), and an inactive OA analog all failed to activate these kinases. The high dose of okadaic acid that is required for kinase activation was also required for phosphatase inhibition, as assessed by immunoblotting whole cell lysates with anti-phosphothreonine antibodies. A variety of chemical inhibitors, including PD98059 (MEK-specific), genistein (tyrosine kinase-specific) and Bisindolylmaleimide I (protein kinase C-specific), failed to inhibit the OA activation of these kinases. Thus, MBPK-55 and MBPK-62 are also Histone IIIS kinases that are widely expressed and specifically activated upon exposure to high OA concentrations.

• 에너지공학
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• 제13권2호
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• pp.166-172
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• 2004

The activated carbon was produced from Sancheong bamboo by steam and carbon dioxide gas activation methods. The carbonization of raw material was conducted at 90$0^{\circ}C$ and gas activation reactions were conducted with respect to various conditions. -activation temperature 750-90$0^{\circ}C$, the flow rate of steam 0.5-2g-$H_2O$/g-char$.$hr, the flow rate of carbon dioxide 5-30$m\ell$-$CO_2$/g-char-min and activation time 1-5 hr. The prepared activated carbons were measured yield, the adsorption capacity of iodine and methylene blue, BET specific surface area and pore size distribution. The adsorption capacity of iodine (680.5-1526.1 mg/g) and methylene blue (18.3-221.5 mg/g) increased with creasing activation temperature and activation time. The adsorption capacity of iodine and methylene blue increased with the activation gas quantity in the range of 0.5-1.5g-$H_2O$/g-charㆍhr, 5-18.9$m\ell$-Co$_2$/g-charㆍmin. But those decreased over those range due to the pore shrinkage. The steam activation method was superior in efficiency to carbon dioxide activation method.

• Carbon letters
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• 제8권2호
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• pp.95-100
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• 2007

A series of activated carbons (ACs) were derived from sugarcane bagasse under two activation schemes: steam-pyrolysis at $600-800^{\circ}C$ and chemical activation with $H_3PO_4$ at $500^{\circ}C$. Some carbons were treated at 400, $600^{\circ}C$, or for 1-3 h, and/or in flowing air during pyrolysis of acid-impregnated mass. XRD profiles displayed two broad diffuse bands centered around $2{\theta}=23$ and $43^{\circ}$, currently associated with diffraction from the 002 and 100/101 set of planes in graphite, respectively. These correspond to the interlayer spacing, Lc, and microcrystallite lateral dimensions, La, of the turbostratic (fully disordered) graphene layers. Steam pyrolysis-activated carbons exhibit only the two mentioned broad bands with enhancement in number of layers, with temperature, and small decrease in microcrystallite diameter, La. XRD patterns of $H_3PO_4$-ACs display more developed and separated peaks in the early region with maxima at $2{\theta}=23$, 26 and $29^{\circ}$, possibly ascribed to fragmented microcrystallites (or partially organized structures). Diffraction within the $2{\theta}=43^{\circ}$ is still broad although depressed and diffuse, suggesting that the intragraphitic layers are less developed. Varying the conditions of chemical activation inflicts insignificant structural alterations. Circulating air during pyrolysis leads to enhancement of the basic graphitic structure with destruction and degradation in the lateral dimensions.

• 멤브레인
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• 제24권4호
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• pp.259-267
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• 2014

PEBAX[poly(ether-block-amide)에 ZIF-8(zeolitic imidazolate framework)의 함량을 0, 1, 3, 7, 10, 20 wt%으로 하여 PEBAX-ZIF 복합막을 제조하였다. 기체투과 실험은 압력 $6kgf/cm^2$ 하에서 25, 35, $40^{\circ}C$로 온도를 달리하여 진행되었고, PEBAX-ZIF 복합막의 ZIF-8 함량 변화에 따른 $C_3H_6$과 $C_3H_8$의 기체투과도와 선택도($C_3H_6/C_3H_8$)를 조사하였다. $C_3H_6$과 $C_3H_8$의 투과기체에 대해 ZIF-8 함량 0~7 wt% 범위에서는 함량이 증가할수록 기체 투과도가 증가하다가 7~20 wt% 범위에서 함량이 증가하면 감소하는 경향을 보였다. 선택도($C_3H_6/C_3H_8$)는 PEBAX-ZIF 7 wt% 복합막에서 3.6~3.8의 값을 가지며, 가장 낮은 활성화에너지 값을 나타냈다.

• Biomolecules & Therapeutics
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• 제21권5호
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• pp.358-363
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• 2013

In the present study, we investigated the effect of intracellular glutathione (GSH) depletion in heart-derived H9c2 cells and its mechanism. L-buthionine-S,R-sulfoximine (BSO) induced the depletion of cellular GSH, and BSO-induced reactive oxygen species (ROS) production was inhibited by glutathione monoethyl ester (GME). Additionally, GME inhibited BSO-induced caspase-3 activation, annexin V-positive cells, and annexin V-negative/propidium iodide (PI)-positive cells. Treatment with rottlerin completely blocked BSO-induced cell death and ROS generation. BSO-induced GSH depletion caused a translocation of PKC-${\delta}$ from the cytosol to the membrane fraction, which was inhibited by treatment with GME. From these results, it is suggested that BSO-induced depletion of cellular GSH causes an activation of PKC-${\delta}$ and, subsequently, generation of ROS, thereby inducing H9c2 cell death.