• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1087-1090
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• 2014

A simple and general method that selectively introduces metal binding sites into a protein can greatly increase the ability to design and biosynthesize artificial metalloproteins. Here, we report the incorporation of a phenanthroline-containing amino acid (Phen-Ala) into proteins in Escherichia coli by using the $tRNA{^{Tyr}}_{CUA}$ and tyrosyl aminoacyl-tRNA synthetase pair (BpyRS) from Methanococcus jannaschii, which was originally developed for a bipyridine-containing amino acid (Bpy-Ala). The incorporation efficiency of BpyRS for Phen-Ala was comparable to that for Bpy-Ala. Because of its high metal-binding ability and characteristic spectral properties, Phen-Ala can be a useful alternative to the existing metal-chelating amino acids for the design and synthesis of artificial metalloproteins.

• Korean Chemical Engineering Research
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• 제46권6호
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• pp.1029-1038
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• 2008

전이금속 산화물의 전구체가 들어있는 합성모액을 수열 반응시켜 전이금속 산화물이 고정된 하이드로탈사이트를 제조하여 이들에 대한 이산화질소의 흡착 성질을 조사하였다. 전이금속 산화물의 분산도, 이산화질소의 흡착량 및 흡착상태를 XRD, SEM, XPS, 질소 흡착등온선, 중량식 흡착법, FT-IR, 승온탈착법으로 조사하였다. 전이금속 산화물은 주로 하이드로탈사이트의 표면에 분산 담지되었으며, 철과 니켈 산화물이 고정된 하이드로탈사이트에 이산화질소가 많이 흡장되었다. 철 산화물이 표면에 분산되어 담지되면 이산화질소의 흡장량이 많지만, 철 산화물이 지나치게 많이 담지되면 덩어리져서 표면의 염기점을 차폐하므로 이산화질소의 흡장량이 오히려 줄어들었다. 철 산화물의 고정량이 적절하면 하이드로탈사이트에서 이산화질소의 흡장세기는 약해지지만, 흡장량은 많아지고 수열 안정성이 증진되었다.

• Journal of Electrochemical Science and Technology
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• 제14권4호
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• pp.377-387
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• 2023

Ni-W/Al₂O₃ nano-composites were electrodeposited on mild steel substrate for mechanical and corrosion resistance applications. This study focused on the preparation of Ni-W/Al₂O₃ nano-composite coating with various quantity of Al₂O₃ incorporations. The addition of Al₂O₃ in the electrolytes were varied from 1-10 g/L in electrolytes and the Al₂O₃ incorporation in Ni-W/Al₂O₃ nano-composite coatings were obtained from 1.82 to 13.86 wt.%. The incorporation of Al₂O₃ in Ni-W alloy matrix influenced the grain size, surface morphology and structural properties were observed. The distributions of Al₂O₃ particle in alloy matrix were confirmed using electron microscopy (FESEM and TEM) and EDAX mapping analysis. The crystal structure informations were studied using X-ray diffraction method and it confirms that the deposits having cubic crystal structure. The better corrosion rate (0.87 mpy) and microhardness (965 HV) properties were obtained for the Ni-W/Al₂O₃ nano-composite coating with 13.86 wt.% of Al₂O₃ incorporations.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.153-158
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• 2012

The hydrogenation of $AlB_2$-type BaGaGe exhibits a metal to insulator (MI) transition, inducing a puckering distortion of the original hexagonal [GaGe] layers. We investigate the electronic structure changes associated with the hydrogen-induced MI transition, using extended H$\ddot{u}$ckel tight-binding band calculations. The results indicate that hydrogen incorporation in the precursor BaGaGe is characterized by an antibonding interaction of $\pi$ on GaGe with hydrogen 1s and the second-order mixing of the singly occupied antibonding $\pi^*$ orbital into it, through Ga-H bond formation. As a result, the fully occupied bonding $\pi$ band in BaGaGe changes to a weakly dispersive band with Ge pz (lone pair) character in the hydride, which becomes located just below the Fermi level. The Ga-Ge bonds within a layered polyanion are slightly weakened by hydrogen incorporation. A rationale for this is given.

• 한국암석학회:학술대회논문집
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• 한국암석회.한국광물학회 2009년도 공동학술발표회 논문집
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• pp.8-8
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• 2009

• Macromolecular Research
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• 제15권3호
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• pp.211-215
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• 2007

Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.

• 한국진공학회지
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• 제4권S2호
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• pp.69-74
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• 1995

The effects of TCA incorporation during annealing process on the SIMOX quality is studied. Silicon wafers are implanted with heavy dose of oxygen ions, and are annealed at $1300^{\circ}C$ for 4 hours. The annealing process is splitted into three conditions due to some differences of low temperature preliminary annealing step which are without pre-annealing step. The specimens are analyzed by several methods, such as AES, XTEM, and TRXFA. TCA incorporation during pre-annealing step is effective in dislocation density reduction and heavy metal content reduction.

• Bulletin of the Korean Chemical Society
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• 제16권4호
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• pp.316-320
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• 1995

The incorporation of metal ion into the Langmuir-Blodgett (LB) film of an itaconate copolymer was investigated. The polymer was prepared via radical copolymerization of monooctadecyl itaconate with triethyleneglycol methyl vinyl ether. The metal ions employed were Na+, Cs+, Mg2+, Fe2+, Al3+, and Fe3+. The surface pressure-area isotherms indicated that all the monolayers studied on subphases with metal ions showed more expanded areas than that observed on pure water. The monolayers showed an irreversible collapse behavior. The collapse pressure of the monolayers was low on subphases containing trivalent metal ions. From the FT-IR spectra by reflection and transmission modes, the formation of carboxylate salts and the uprisen orientation of the pendant against substrate surface in the polymer LB film were determined. It was estimated by XPS measurement that ca. 13.1 repeat units of the polymer contain one Na+ ion, while one Mg2+ ion corresponds to 5.9 carboxyls.

• 한국환경농학회지
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• 제33권3호
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• pp.155-163
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• 2014

BACKGROUND: Recent studies for heavy metal stabilization in soil were mainly focused on finding out new materials and its efficiency. But, such a stabilization method can cause disturbance to soil, leading improper environment for agriculture. The object of this study was to demonstrate the effect of the incorporation of green manure crops on heavy metal-contaminated soil. METHODS AND RESULTS: Soil contaminated with heavy metals was collected from the agricultural soils affected by the abandoned mine. Lime stone was selected and treated to contaminated soil. Three kinds of legume green manure crops; Alfalfa (Medicago sativa), Hairy vetch (Vicia villosa), Red clover (Trifolium pratense) were subsequently cultivated in greenhouse condition. It was found that lime stone increased soil pH and decreased the amount of heavy metal absorption by green manure. The application of green manure residues on soil increased soil pH and inorganic nitrogen. CONCLUSION: The C/N ratio of three green manures was low, indicating fast decomposition rate, resulting in nitrogen supplement, consequently. Considering the point that the soil was used for agricultural purpose, it was recommended that hairy vetch and red clover were preferred. Nevertheless, the heavy metal availability was also increased. Thus, it seemed that further study was needed to confirm that how long maintain a phenomenon.

• 아시안잔디학회지
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• 제16권1호
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• pp.19-30
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• 2002

경직된 지반의 물리성 개선재로서 rubber chip의 토양 내 혼합 또는 배토는 잔디의 생육과 지반의 이·화학성 및 중금속 추출 실험을 통하여 다음과 같은 결론을 얻었다. Rubber chip의 토양 내 혼합은 지면의 온도 상승효과를 가져왔으며 이는 겨울철의 동해방지 및 맹아출현기를 앞당길 수 있을 것이라 추정된다. 그러나 복사열이 높은 여름에는 rubber chip에 의한 표면, 지중 온도의 상승으로 잔디의 피해가 우려된다. 또한 토양 내에 rubber chip의 혼합함량(rubber chip 20%, 40%)이 많을수록 잔디의 발아와 생육 및 피복에 부정적인 영향을 끼쳤다. Rubberchip의 토양혼합은 지반의 이·화학성 변화에 크게 작용하지 않았으며 중금속 추출실험에서도 차이를 나타내지 않아 토양환경 오염이 없을 것으로 판단된다. Rubber chip을 배토용 재료로서 사용했을 경우, 경직된 토양구조를 개선시켜 주었다. 특히 통기작업 후 rubber chip의 배토는 지반의 표면탄성을 현저히 완화시켰다. 따라서 현재 우리나라에서 보수중이 거나 건설중인 연습구장, 보조구장에 재활용이 가능한 폐타이어 rubber chip을 지반 답압 개선용, 배토용 재료로서 사용이 가능할 것으로 판단된다.