• Membrane and Water Treatment
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• v.9 no.1
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• pp.63-68
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• 2018

Molecular dynamics simulations were used to study the removal of Cd(II) as a heavy metal from wastewater using armchair carbon nanotube, boron nitride nanotube and silicon carbide nanotubes under applied electric field. The system contains an aqueous solution of $CdCl_2$ as a heavy metal and a (7,7) nanotube as a nanostructured membrane, embedded in a silicon nitride membrane. An external electric field was applied to the considered system for the removal of $Cd^{2+}$ through nanotubes. The simulation results show that in the same conditions, considered armchair nanotubes were capable to remove $Cd^{2+}$ from wastewater with different ratios. Our results reveal that the removal of heavy metals ions through armchair carbon, boron nitride and silicon carbide nanotubes was attributed to the applied electric field. The selective removal phenomenon is explained with the calculation of potential of mean force. Therefore, the investigated systems can be recommended as a model for the water treatment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1058-1061
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• 2003

In this thesis, we observed the optical characteristic of amorphous chalcogenide thin films by He-Cd laser. Also, grating formation by He-Ne laser and He-Cd laser. After analyze diffraction efficiency of the time on the $Ag(200{\AA})/As_{40}Ge_{10}Se_{15}S_{35}$ thin films. The result diffraction efficiency of Maximun 0.2% reduced according to time grating formation by He-Ne laser. Diffraction efficiency of Maximun 0.1% showed stabiliy characteristic according to time grating formation by He-Cd laser.

• Transactions on Electrical and Electronic Materials
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• v.3 no.2
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• pp.28-31
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• 2002

The Cdl-xZnxTe film was fabricated by thermal evaporation for the flat-panel X-ray detector. The stoichimetric ratio and the crystal structure of a polycrystalline Cd$_{1-x}$ Zn$_{x}$Te were investigated by EPMA and XRD, respectively. The leakage current and X-ray sensitivity of the fabricated films were measured to analyze the X-ray response characteristic of Zn in the polycrystalline CdZnTe thin film. The leakage current and the output charge density of Cd$_{0.7}$Zn$_{0.3}$Te thin film were measured to 0.37 nA/cm$^2$ and 260 pc/cm$^2$ at an applied voltage of 2.5 V/${\mu}{\textrm}{m}$, respectively. Experimental results showed that the increase of Zn doping rates in Cd$_{1-x}$ Zn$_{x}$Te detectors reduced the leakage current and improved the signal to noise ratio significantly.

• Journal of Sensor Science and Technology
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• v.14 no.6
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• pp.369-373
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• 2005

High quality CdTe single crystal for the solar cell fabrication was grown by vertical Bridgman method. The etch pits patterns of (111) surfaces of CdTe etched by Nakagawa solution was observed the (111)A compesed of Cd atoms with typical triangle etch pits of pyramid mode. From the photoluminescence measurement on (111)A, we observed free exciton ($E_{x}$) existing only high quality crystal and neutal acceptor bound exciton ($A^{0}$,X) having very strong peak intensity. Then, the full width at half maximum and binding energy of neutral acceptor bound exciton were 7 meV and 5.9 meV, respectively. By Haynes rule, an activation enery of impurity was 59 meV. Therefore, the origins on impurity level acting as a neutral acceptor were associated Ag or Cu elements.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.20 no.1
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• pp.14-21
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• 2017

Pediatric onset Crohn's disease (CD) tends to have complicated behavior (stricture or penetration) than elderly onset CD at diagnosis. Considering the longer duration of the disease in pediatric patients, the accumulative chance of surgical treatment is higher than in adult onset CD patients. Possible operative indications include perianal CD, intestinal stricture or obstruction, abdominal abscess or fistula, intestinal hemorrhage, neoplastic changes and medically untreatable inflammation. Growth retardation is an operative indication only for pediatric patients. Surgery can affect a patient's clinical course, especially for pediatric CD patient who are growing physically and mentally, so the decision should be made by careful consideration of several factors. The complex and diverse clinical conditions hinder development of a systemized treatment algorithm. Therefore, timing of surgery in pediatric CD patients should be determined with individualized approach by an experienced and well organized multidisciplinary inflammatory bowel disease team. Best long-term outcomes will require proactive post-operative monitoring and therapeutic modifications according to the conditions.

• Journal of the Korean Vacuum Society
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• v.3 no.3
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• pp.355-359
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• 1994

Cd1-xCoxIn2Se4(X=0.50) 결정을 수직 Bridgman 방법으로 성장시키고 성장된 결정의 결정구조 및 XPS 특성을 연구하였다. 성장된 결정은 pseudocubic 구조이고 격자상수는 a=5.778$\AA$으로 주어졌다. Cd1-xCoxIn2Se4 결정의 각 성분원소인 cadmium cobalt indium 그리고 selenium에 대한 XPS spectrum으 로부터 결합에너지와 결합상태를 조사하였다. Cd1-xCoxIn2Se4결정과 결합하지 안는 각 성분원소인 cadium cobalt imdium 그리고 selenium에 대한 core level의 XPS spectrum과 비교하면 각 성분원소상 이의 결합에 의한 chemical shift 현상 때문에 core level의 결합에너지가 0.10~4.87 eV 차이가 있다. Cd1-xCoxIn2Se4 결정에서 Co 2P3/2 core level의 주 peak와 statellite peak와의 결합에너지 차이로부터 cadmium과 치화된 cobalt는 Co2+ ion으로 Td symmetry 점에 위치함을 알 수 있다.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.4
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• pp.107-111
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• 2019

We report the fabrication of a CdS/CuInGaSe (CdS/CIGS) structure with carbon nanotubes and its application as a photocathode for photoelectrochemical water splitting. CIGS thin films were fabricated using co-evaporation by RF magnetron sputtering, while CdS was fabricated by chemical bath deposition. Spray coated multi-wall carbon nanotube (CNT) film on CdS/CIGS thin film was investigated as a photocathode. The CNT-coated CdS/CIGS showed superior photocurrent density and exhibited improved photostability.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.590-594
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• 2013

Semiconductor CdSe nanowires (NWs) can serve as model systems for investigating the physical properties of one-dimensional (1D) nanostructures and have great potential for applications in electronics and photonic nanodevices. With numerous attractions arisen from their physical properties, CdSe NWs have been synthesized by vapor-liquid-solid (VLS) methods, but they have some limitations of high reaction temperature and low production. Here, we synthesized CdSe NWs via the solution-liquid-solid (SLS) mechanisms using bismuth (Bi) covered substrates as a low-melting point catalyst and compared the products after injecting identical amount of Se and different amount of tributylphosphine (TBP). CdSe NWs have similar diameters but longer lengths with decreasing TBP, so we proposed the role of TBP as a solvent and capping agent of Se.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.289-294
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• 1997

The cycles of heavy metals, mercury, lead and cadmium, were investigated on in dynamic grassland ecosystems at a steady state in Zoysia japonica and Miscanthus sinensis in Mt. Kwanak, Korea. Estimates of decay constants of heavy metals based on experimental and methomatical model, were Hg 0.14, Pb 0.17 and Cd 0.41 of Z. japonica grassland, and Hg 0.33, Pb 0.13 and Cd 0.56 of M sinensis grassland. The durations of reaching half of initial amounts in Z. japonica and M. sinensis grassland, were Hg 4.95, Pb 4.07 and Cd 1.69 years, and Hg 2.10, Pb 5.33 and Cd 1.24 years respectively. Times needed for 99% decomposed were longer in Z. japonica than M. sinensis grassland. Decay velocity of constituents of surface soil layers were more rapidly in M. sinensis than Z. japonica grassland. Key words: Cycles of heavy metals, Mercury, Lead, Cadmium, Zoysia japonica. Miscanthus sineusis, Mt. Kwanak, Decay constants.

• New & Renewable Energy
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• v.17 no.4
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• pp.36-45
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• 2021

To remove the Cu secondary phase remaining on the surface of a CIGSSe absorber layer manufactured by the two-step process, KCN etching was applied before depositing the CdS buffer layer. In addition, it was possible to increase the conversion efficiency by air annealing after forming the CdS buffer layer. In this study, various pre-treatment/post-treatment conditions wereapplied to the S-containing CIGSSe absorber layerbefore and after formation of the CdS buffer layer to experimentally confirm whether similareffects as those of Se-terminated CIGSe were exhibited. Contrary to expectations, it was noted that CdS air annealing had negative effects.