• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.3033-3038
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• 2012

The hydrogen storage mechanism of graphite was studied by measuring the electrical resistance change. Graphite was expanded and activated to allow for an easy hydrogen molecule approach and to enlarge the adsorption sites. A vanadium catalyst was simultaneously introduced on the graphite during the activation process. The hydrogen storage increased due to the effects of expansion, activation, and the catalyst. In addition, the electrical resistance of the prepared samples was measured during hydrogen molecule adsorption to investigate the hydrogen adsorption mechanism. It was found that the electrical resistance changed as a result of the easy hydrogen molecule approach, as well as of the adsorption process and the catalyst. It was also notable that the catalyst improved not only the hydrogen storage capacity but also the speed of hydrogen storage based on the response time. The hydrogen storage mechanism is suggested based on the effects of expansion, activation, and the catalyst.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.439-444
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• 2008

The oyster shell adsorbents were prepared by steam activation method to evaluate their adsorption characteristics. Washed and pulverized waste oyster shells were prepared by steam activated process in converter at the temperature range of about $700{\sim}800^{\circ}C$ after carbonized at the range of $600{\sim}1000^{\circ}C$. The shell carbonized at $1000^{\circ}C$ showed the best performance among those of other temperature ranges. Also, comparison between gas and liquid phase adsorption was performed to verify adsorbent possibility of waste shell. In case of gas phase, the adsorbent showed lower performance than existing commercial adsorbents. On the other hand, the liquid phase, they showed similar adsorption performance to commercial adsorbents when benzene was used.

• Korean Journal of Materials Research
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• v.17 no.8
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• pp.402-407
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• 2007

In electronics manufacturing processes, soldering process has generally been used in surface mounting technology. Because of environmental restriction, lead free solders as like a SnAgCu ternary system are being used widely. After soldering process, the formation and growth of intermetalic compounds(IMCs) are formed in the interface between solder and Cu substrate as follows isothermal temperature and time. In this studies, therefore, we investigated the effects of the Cu substrate thickness on the IMC formation and growth of Sn-40Pb/Cu and Sn-3.0Ag-0.5Cu/Cu solder joints, respectively. The effect of the Cu thickness in PCB Cu pad and pure Cu plate was analyzed as measuring of thickness of each IMC. After solder was soldered on PCB and Cu plate which have different Cu thickness, we measured the IMC thickness in solder joints respectively. Also we compared with the effectiveness of Cu thickness on the IMC growth. From these results, we calculated the activation energy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.7
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• pp.557-563
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• 2003

SiC has been an useful material for the high voltage, high temperature, and high frequency devices, however, the required high process temperature to activate the implanted p-type dopants has hindered further developments. In this study, we report, for the first time, on the laser activation of implanted Al and non-alloyed Mo ohmic contacts and its application to MOSFET fabrication. The contact and sheet resistance measured from CTLM patterns have decreased by increasing laser power, and the lowest values are 3.9 $K\Omega$/$\square$ and 1.3 $\times$ 10$^{-3}$ $\Omega$-cm$^2$, respectively, at the power density of 1.45 J/cm$^2$ The n-MOSFETs fabricated on laser activated p-well exhibit well-behaved I-V characteristics and threshold voltage reduction by reverse body voltage. These results prove that the laser process for implant activation is an alternative low temperature technology applicable to SiC devices.

• Hwankyungkyoyuk
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• v.13 no.1
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• pp.111-121
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• 2000

The purpose of this study was to investigate and evaluate the state of School Forest Movement by the School Forest Committee of the ‘Forest for Life’, and to provide schools and social communities with alternative, for activation through foreign and domestic case studies. School Forest Movement is very important and has great effect on many aspects, such as the improvement of school environment, the expansion of environmental education in school, the enhancement of local membership and increasing participation of school community. School Forest Movement has expanded from 10 schools in 1999 for pilot implementation to 20 in 2000. Now, it Is broadly recognized that the movement should be expended nationally A few problems were observed through pilot implementation. School community has little consensus away member and hardly participates in the movement, and the process is often underestimated, comparing to the result. For activation of School Forest Movement, school community should be cooperate to local community. Especially, the stepwise execution of School Forest Movement should be well organized and School Forest Movement should be changed into a process-oriented movement for more participation of school community including students, teachers, parents and.

• Journal of Adhesion and Interface
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• v.23 no.4
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• pp.101-107
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• 2022

Adhesive joints have many advantages such as weight savings, corrosion and fatigue resistance and now developed even withstand of high impact and dynamic loads. However, an adhesion has cumbersome and complicated surface preparation processes. The surface preparation step is critical in adhesive joint manufacturing in order to obtain the prescribed strength for adhesive joints. In this study, it was attempted to simplify and reduce the number of surface preparation steps, and abrasion and rapid adhesive application (ARAA) process is developed for an alternative solution. The abrasion processes are performed only for creating surface roughness in standard procedures (SP), although the abrasion processes cause surface activation itself. The results showed that there is no need the long procedures in laboratory or chemical agents for adhesion. After the abrasion process, the attracted and highly reactive fresh surface layer obtained, and its effect on bonding success is observed and analyzed in this research, in light of the essential physic and adhesion theories. Al 6061 aluminum adherends and epoxy-based adhesives were chosen for bonding processes, which is mostly used in light vehicle parts. The adherends were cleaned, treated and activated only with abrasion, and after the adhesive application the specimens were tested under quasi-static loading. The satisfied ARAA results were compared with that of the specimens fabricated by the standard procedure (SP) of adhesion processes of high impact loads.

• Journal of the Korean Chemical Society
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• v.14 no.4
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• pp.309-319
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• 1970

Composition of Acid Clay, the raw material for activated clay manufacturing, was investigated to develop useful data in deciding activation condition. Speculations on components and structure of activated clay were also made in order to see how included components of raw materials change during activation process. And a study was made on relations between structure of activated its adsorptivity. For this research, theremogravimetric analysis, X-ray differaction analysis and calculation of adsorptive index were carried out.

• Proceedings of the KSPS conference
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• 2003.05a
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• pp.97-100
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• 2003

The present study was planned to investigate the cortical activation correlated with producing morphologically complex Korean verbs by using. fMRI technique. In this study two derivational affixes and two inflectional affixes were selected: pre-final ending and final ending for inflectional affix and passive affix and causative affix for derivational affix. Two Experiment were conducted. The results of two Experiments suggest a possibility that process of pre-final ending is different from final ending.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2145-2149
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• 2018

The formation of methanol directly from methane and steam was observed over Cu ion-exchanged mordenite. Furthermore, the continuous production of methanol was achieved by co-feeding methane and steam over Cumordenite. The methanol production rate was comparable to that reported in the stepwise process in which activation, methane reaction, and extraction of methanol were carried out separately.

• Journal of the Korean Institute of Rural Architecture
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• v.4 no.3
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• pp.39-52
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• 2002

Some projects being in force by the Ministry of Government Administration & Home Affairs and the Ministry of Agriculture & Forestry for farm village area activation offers experience activity of various form to city dwellers, and to farm village inhabitants, affirmative effect is expected in aspect that activation becomes possible for a lot of visitors. But, to farm village(rural district) area activation that huge budget and effort carried out successfully, there are some items that specialist, administration and the persons concerned must inspect together now. First, to project for farm village area activation succeeds; leading participation of inhabitants should be premised. Second, that stagnated economy revives is as rightful result that appears in case farm village area activation effort succeeds. But, can drop more highlights like the value pursuit of life in case put success or failure of all businesses in income enlargement. Third, because inhabitant cultivates own in making process, the attachment and pride for area can be inculcated. Doing not become focus is set to economical logic to do, the heritage of area as well as history culture, must consider that apply eco-museum concept that magnify nature heritage and industry heritage. Fourth, actually the plan period given usually is too shortly than received huge budget. Furthermore, in case it carries out by desirable inhabitants leading type so. Project that not consider the period that is cost to the statement of inhabitants' active opinion and finding out a point of compromise may be hard to get desirable result.