• 한국수소및신에너지학회논문집
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• 제14권3호
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• pp.207-216
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• 2003

By using the electrochemical method, the relation between the deformation and the geometrical shape, and the effect of cold work on hydrogen absorption-desorption cycling in palladium were investigated, In order to study this problem, four kinds of the Pd specimens used were plates and bars as cold worked and annealed states. As results, it is found that the deformation of thickness direction in the palladium plates increased whereas other lateral directions decreased. But the palladium bars showed the same deformation ratio in all directions because of uniform distribution of the $\beta$ phase. Grains in the plate specimens were greatly deformed after hydrogenation cycling whereas grains in the bar specimens were pulverized. Also, deterioration of the hydrogen absorption rate of the bar specimen was larger than the plate specimen. And the effect of cold work on hydrogen absorption capacity was relatively small.

• 한국수소및신에너지학회논문집
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• 제17권2호
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• pp.234-240
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• 2006

Al film(135.5 nm thick) with Pd film(39.6 nm thick) on the top of it was made by thermal evaporation method. Hydrogen absorption of Al/Pd film was measured by quartz crystal microbalance(QCM) method at room temperature. The sample was activated by hydrogen absorption and desorption cycling at room temperature. Hydrogen was introduced into the film by increasing hydrogen gas pressure step by step up to 640 torr at room temperature. Hydrogen concentration reached up to 25% at $5{\sim}10$ torr. But at high pressure the concentration decreased. This strange tendency was not understood yet. Further study is needed to find out the mechanism of hydrogen absorption in Al in Al/Pd film.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 춘계학술논문요약집
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• pp.309-310
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• 2018

• 자원리싸이클링
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• 제30권4호
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• pp.35-45
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• 2021

본 연구에서는 폐닥나무 섬유를 사용한 목모보드의 제조 및 조습 특성 분석을 수행하였다. 목모보드 제조를 위해 폐닥나무 섬유의 분쇄 시간을 30, 60, 120, 180초로 제어하였으며, 혼합량을 시멘트 대비 0, 3, 6, 9% 수준으로 외할 첨가하여 제어하였다. 분쇄시간 제어 조습섬유 혼입 목모보드의 흡·방습 특성 분석 결과, 60초 분쇄 섬유 혼합 목모보드가 흡·방습 성능이 뛰어난 것으로 확인되었으며, 이는 분쇄 섬유의 손상이 적어 소재 자체의 흡·방습 성능이 보드 혼합 시에도 발현되었기 때문이다. 또한 섬유 혼합량 제어 목모보드의 흡·방습 특성 분석 결과, 6% 혼합 목모보드가 흡·방습 특성이 가장 뛰어났으며, 흡습 및 방습량은 각각 291.00g/m² 및 108.75g/m²으로 확인되었다.

• 한국수소및신에너지학회논문집
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• 제18권3호
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• pp.334-341
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• 2007

Al film(135.5 nm thick) with Pd film(39.6 nm thick) was made by thermal evaporation method. Electrical resistance change by hydrogen absorption and desorption was measured with four point measurement method. Even though Al film(135.5 nm thick) did not absorb any hydrogen at room temperature, Al/Pd film absorbed hydrogen at upto 640 torr pressure. Hydrogen absorption kinetics was monitored by measuring resistance change of the sample in the temperature range from $25^{\circ}C$ to $40^{\circ}C$. Absorption activation energy of Al/Pd film was about 10.7 and 17.7 kcal/mol H for 1st stage and last stage respectively at 1 torr hydrogen pressure. This activation values are bigger than that of Pd film, but are much less than that of Al film. This result indicates there is possibility that Al can be storage material for hydrogen by using Pd film evaporation on it.

• 한국수소및신에너지학회논문집
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• 제19권3호
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• pp.199-208
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• 2008

HI decomposition was conducted using Pt/C-based catalysts with a fixed-bed reactor in the range of 573 K to 773 K. To examine the change of the characteristic properties of the catalysts, $N_2$ adsorption analyser, a X-ray diffractometer(XRD), and a scanning electron microscopy(SEM) were used before and after the HI decomposition reaction. the effect of Pt loading on HI decomposition was investigated by $CO_2$-TPD. HI conversion of all catalysts increased as decomposition temperature increased. The XRD analysis showed that the sizes of platinum particle became larger and agglomerated into a lump during the reaction. From $CO_2$-TPD, it can be concluded that the cause for the increase in catalytic activity may be attributed to the basic sites of catalyst surface. The results of both b desorption and gasification reaction showed the restriction on the use of Pt/C-based catalyst.

• Korean Chemical Engineering Research
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• 제48권6호
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• pp.752-756
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• 2010

시화/반월 산단 내에서 활성탄 흡착탑을 사용하는 업종 중 도장 공정을 사용하는 대표적인 업체에서 수거한 폐활성탄의 탈착특성을 조사하였다. 탈착특성을 조사하기 위하여 열중량분석기(Thermogravimetric Analyzer)를 사용하였다. 탈착특성 자료를 바탕으로 탈착 특성비교에 중요한 요소인 반응차수와 활성화에너지를 구하기 위하여 Friedman법과 Freeman-carroll법을 사용하였다. 도장 공정에서 수거한 폐활성탄으로 Friedman법을 이용하여 활성화에너지를 계산한 결과 20.6~43.2 kJ/mol을 나타내었으며, Freeman-Carroll법을 이용하여 활성화에너지와 반응 차수를 계산한 결과 활성화에너지는 12.3~26.5 kJ/mol, 반응 차수는 0.1~1.7을 나타내었다.

• Nuclear Engineering and Technology
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• 제40권6호
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• pp.489-496
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• 2008

Ferrocyanide-anion exchange resin was prepared and the prepared ion exchange resins were tested on the ability to uptake $Cs^+$ ion. The prepared ion exchange resins were resin-KCoFC, resin-KNiFC, and resin-KCuFC. The three tested ion exchange resins showed ion exchange selectivity on the $Cs^+$ ion of the surrogate soil decontamination solution, and resin-KCoFC showed the best $Cs^+$ ion uptake capability among the tested ion exchange resins. The ion exchange behaviors were explained well by the modified Dubinin-Polanyi equation. A regeneration feasibility study of the spent ion exchange resins was also performed by the successive application of hydrogen peroxide and hydrazine. The desorption of the $Cs^+$ ion from the ion exchange resin satisfied the electroneutrality condition in the oxidation step; the desorption of the $Fe^{2+}$ ion in the reduction step could also be reduced by adding the $K^+$ ion.

• 한국수소및신에너지학회논문집
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• 제9권3호
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• pp.111-118
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• 1998

The intrinsic degradation behavior of $(V_{0.53}Ti_{0.47})_{0.925}Fe_{0.075}$ alloy with BCC structure and the two plateau regions (the low and high plateau region) has been investigate during the temperature-induced hydrogen absorption-desorption cycling (thermal cycling). After 400 thermal cycles between room temperature and $600^{\circ}C$ under 10atm $H_2$, the total reversible hydrogen absorption capacity decreased by about 40%. From thermal desorption analysis it was found that the degradation behavior at each plateau region was different. In addition, XRD analysis showed that the crystal structure of the sample in de-hydrided state was changed from BCC to BCT after degradation, and that of the sample in hydrided state it was maintained as FCC although peaks were broadened after degradation. From the result of static isothermal hydrogenation treatment it were found that crystal structure change from BCC to BCT was caused by the thermal energy. TEM analysis showed that the peak broadening was due to the formation of an amorphous phase in FCC matrix.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2241-2242
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• 2013