• 미생물학회지
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• 제30권4호
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• pp.310-315
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• 1992

수용액으로부터 $Pb^{2+}$ 의 흡수와 분리를 Staphylococcus epidermidis 를 이용하여 조사하였다. 흡수된 $Pb^{2+}$의 양을 초기 $Pb^{2+}$ 의 양에 대한 비율로 나타낸 것을 흡수율이라고 정의할 경우, 세균체의 농도가 높을수록 흡수율은 증가하였으며 세균체 단위 중량당 흡수율은 감소하였다. $Pb^{2+}$ 의 흡수율은 수용액의 pH 가 상승함에 따라 점차 증가하다가 최고치를 나타낸 후 감소하는 경향을 보였으며 $Pb^{2+}$ 의 농도가 증가할수록 흡수율의 최고치는 더 낮은 pH 에서 나타났다. HCI 과 EDTA 는 효과적인 탈락체로 작용하였으며 흡수와 탈착 cycle 의 횟수에 따른 세균체의 $Pb^{2+}$에 대한 흡수 능력에는 거의 변화가 없었다.$Pb^{2+}$ 이 다른 중금속 이온과 함께 혼재할 경우 세균내의 결합위치에 대한 경쟁적인 흡수로 인하여 $Pb^{2+}$ 의 흡수율이 변화하였으며, 공존하는 중금속 이온의 이온 반경이 작을수록$Pb^{2+}$ 의 흡수율이 더 크게 감소하였다.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.46-47
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• 1982

1. The physical and anatomical properties investigated in this study are the ones, which may give more effect on absorption of preservatives, such as variation of annual ring, specific gravity, shrinkage, E.M.C. of desorption and adsorption at 70 percent relative humidity condition, general and minute properties of wood. 2. On this study, the positive effects of wood structure, in particular, the appearances of tyloses in vessel element upon the absorption of creosote were observed. 3. Thirteen percent sodium chloride solution treatment and boiling hot water treatment have shown poor results to improve the preservative absorption characteristics of tested species however, some slight difference between treated and control could be seen. (see Tables 6 and 7).

• 대한금속재료학회지
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• 제47권6호
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• pp.372-377
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• 2009

We report on hysteresis behavior in the electrical resistance-hydrogen concentration of Pd thin films. The variation of the electrical resistance has been investigated during the process of absorption and desorption of hydrogen gas ($H_{2}$) as a function of thickness of Pd thin films. The hysteresis behavior in the electrical resistance with $H_{2}$ concentration was found for Pd thin films and consists of $\alpha$ phase, ${\alpha}+{\beta}$ phase, and $\beta$ phase regions. The sensitivity of Pd thin films with $H_{2}$ concentration was found to follow Sieverts' law in the $\alpha$ phase region. However, the sensitivity was observed to increase abruptly with $H_{2}$ concentration in the ${\alpha}+{\beta}$ phase co-exist region. This is because Pd-H interaction is stronger in the $\beta$ phase than in the $\alpha$ phase and needs a higher concentration gradient as a driving force to desorb. The formation of the $\beta$ phase also was observed to cause the structural change because of the lattice expansion during absorption. The hysteresis height and the trace of structural change were affected by the thickness of the Pd film. As the film becomes thinner, the hysteresis height becomes lower and the amount of delamination on the surface becomes smaller. For films thinner than 20 nm in thickness, the delamination was not found but electrical resistance hysteresis was still observed.

• Mass Spectrometry Letters
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• 제15권1호
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• pp.26-39
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• 2024

Gold nanostructures (Au NSs) are useful and interesting matrices for mass spectrometric analysis of various biomolecules based on organic matrix-free laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS). Au NSs provide high efficiency and versatility in LDI-TOF-MS analysis based on their well-established synthesis and surface functionalization, large surface area, high laser absorption capacity, and photothermal conversion efficiency. Therefore, Au NSs based LDI-TOF-MS can be a facile, functional, and efficient analytical method for important small biomolecules owing to its simple preparation, rapid analysis, salt-tolerance, signal reproducibility, and quantitative analysis. This review chronologically summarizes the important advance of Au NSs-based LDI-TOF-MS platforms in terms of in-depth mechanism, signal enhancement, quantitative analysis, and disease diagnosis.

• 보존과학회지
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• 제30권2호
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• pp.235-241
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• 2014

본 연구에서는 활성탄의 문화재 전시 환경에 대한 습도 및 유해물질 제어 능력을 확인하고자 하였다. 흡 방습 성능 실험 결과, 저습과정(RH $30{\rightarrow}55{\rightarrow}30%$)에서는 박물관에서 주로 사용되는 Silica계 조습제에 비해 활성탄의 흡습량이 많은 반면 방습량은 적었다. 흡습속도는 활성탄이 Silica계 조습제에 비해 빠르고 방습속도는 Silica계 조습제가 빨랐다. 중습과정(RH $50{\rightarrow}75{\rightarrow}50%$)에서는 활성탄에 비해 Silica계 조습제의 흡습량이 근소하게 많았으며 방습량은 비슷하게 나타났다. 흡 방습 속도는 활성탄의 흡습 속도가 Silica계 조습제에 비해 빠르고 방습속도는 큰 차이를 보이지 않았다. 유해물질 흡착 실험에서는 활성탄을 적용한 환경이 Silica 계 조습제를 적용한 환경에 비해 Formaldehyde의 농도가 낮았다.

• 한국수소및신에너지학회논문집
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• 제12권4호
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• pp.247-255
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• 2001

The relation between the deformation and the geometrical shape, and the effect of cold work on the hydrogen absorption behavior in palladium were investigated. The Pd specimens used were plates and wires as cold worked and annealed states. The palladium plates and wires were loaded with hydrogen by electrochemical method. Experimental analyses were carried out through X -ray diffraction, micrometer measurement and decimal balance measurement. As the results, it is found that the effect of cold work on hydrogen absorption capacity was relatively small. The deformation of the palladium plates in thickness direction is larger than in other lateral directions whereas the palladium wires showed the same deformation ratio in all radius directions because of the circular distribution of coexisting $\alpha$ and $\beta$ phases. The products of plastic deformation such as slip lines and voids etc. were observed abundantly in all specimens although the specimens had undergone only once of a hydrogen absorption and desorption.

• 한국수소및신에너지학회논문집
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• 제7권2호
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• pp.173-180
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• 1996

4-probe resistivity measurement technique was used to study kinetics of hydrogen absorption-desorption on Pd film($520{\AA}$ thick) at room temperature upto 1 bar. Kinetics data are fitted well to 1st order kinetics equation in ${\alpha}$ and ${\alpha}^{\prime}$ phases. In ${\alpha}+{\alpha}^{\prime}$ phase, absorption kinetics was very complicated, but it could be explained partially with nucleation and growth process. Ln(dR/dt) vs. time plot gives rate constant k value(R is resistance of sample, t is time). k value for absorption is $4^{-6}{\times}10^{-4}/sec$ in ${\alpha}$ phase. k is increasing upto $4^{\times}10^{-2}/sec$ as hydrogen pressure increasing in ${\alpha}^{\prime}$ phase. k is proportional to ln(Pop/Peq), where Peq is equilibrium plateau pressure and Pop is the opposing pressure. In contrast to bulk sample k value was decreasing with increasing number of A-D cycling in ${\alpha}^{\prime}$ phase absorption.

• 대한건축학회논문집:구조계
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• 제34권3호
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• pp.43-52
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• 2018

This study is conducted to evaluate the performance of ceramic panels and painting materials for humidity control which are developed in non-plastic room temperature hardening structure as part of a project to improve a residential environment for the low-income class, rather than the performance of high-priced humidity control materials that are produced with the existing plasticity processing. The testing methods included the measurements of absorption & desoprtion of humidity per material; Mock-up Testing; an evaluation method of comparing the absorption & desoprtion performances of Ecocarat, ceramic panels and painting materials through Living Lab. According to the measurements of absorption & desoprtion per material, ceramic panels, E panel, and ceramic painting material showed 73.3g/m2, 96.6g/m2, and 111.1g/m2, respectively. That is, the performance of humidity control of each material was found to be good in the order of: Ceramic Paint > E panel > Ceramic Panel. According to performance evaluation testing with Mock-up test and Living Lab, Ceramic Paint, Ecocarat, and Ceramic Panels showed better absorption & desoprtion performances in the order.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.87-88
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• 2012

Metal oxide nanostructures have been applied to various fields such as energy, catalysts and electronics. We have freely designed one and two-dimensional (1 and 2-D) metal (transition metals and lanthanides) oxide nanostructures, characterized them using various techniques including scanning electron microscopy, transmission electron microscopy, X-ray diffraction crystallography, thermogravimetric analysis, FT-IR, UV-visible-NIR absorption, Raman, photoluminescence, X-ray photoelectron spectroscopy, and temperature-programmed thermal desorption (reaction) mass spectrometry. In addition, Ag- and Au-doped metal oxides will be discussed in this talk.

• 한국수소및신에너지학회논문집
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• 제12권3호
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• pp.201-209
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• 2001

The change of optical transmittance of $PdH_x$ thin film due to hydrogen concentration change was measured at room temperature. Pd film($312{\AA}$ thick) was made by thermal evaporation on glass substrate. Hydrogen absorption and desorption cycling effect on optical transmittance was measured 4 times in the pressure range between 0 and 640 torr. Ratio of optical transmittance to the change of ln pressure(torr) increases with increasing number of hydrogen A-D cyclings in the ${\beta}$ phase.