• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.255-260
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• 2012

A new series of silaanthracenophanes 2-5 composed of 1,8-diethynylanthracene unit has been synthesized from silylation reactions of 1,8-di(lithioethynyl)anthracene with 1,3-dichloro-1,1,3,3-tetraalkyldisiloxanes and 1,2-dichlorotetramethyldisilane. The silaanthracenophane products 2-4 were characterized by spectroscopic methods and X-ray crystallographic analysis.

• 한국분말재료학회지
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• 제14권3호
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• pp.180-184
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• 2007

The material design and synthesis are of important to modem science and technology. Here, we report the synthesis of multifunctional nanomaterials with different properties: feroelecties $YMnO_3$ and multiferroic materials such as $CoFe_2O_4-YMnO_3,\;Fe_3O_4-YMnO_3,\;CoFe_2O_4-Cd_{0.85}Zn_{0.15}S,\;and\;Fe_3O_4-Cd_{0.85}Zn_{0.15}S$ nano-composites by using a chemical synthesis process. These results provide a simple and convenient synthesis process to produce multifunctional nanocomposites.

• Carbon letters
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• 제5권2호
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• pp.68-74
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• 2004

The polymer with contents of $C_{60}$ up to 57 wt.% was produced by mutual condensation of fullerene $C_{60}$ and ethylenediamine. The investigations of this polymer as well as pristine fullerene to comparison were carried out by FT-IR and UV-Vis spectroscopy, ToF-SIMS, TGA, and elemental analysis. At least three kinds of components was revealed as building blocks of polymer. The fullerene cage underwent only distortion but didn't destroy during formation of polymer. The pure fullerene was found as an intermediate of the thermal decomposition of polymer. The conclusion that this polymer could serve as precursor to produce carbon nanomaterial with high concentration curved graphene sheets and can be used for gas adsorption and electrochemical application was made.

• KSBB Journal
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• 제30권1호
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• pp.1-10
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• 2015

Nanomaterial-based artificial enzymes (Nanozymes) have attracted recent attention because of their unique advantageous characteristics such as excellent robustness and stability, low-cost production by facile scale-up, and longterm preservation capability that are critically required as an alternative to natural enzymes. These nanozymes exhibit natural enzyme-like activity, and they have been applied to diverse kinds of detection methods for disease-associated biomolecules such as DNAs, proteins, cells, and small molecules including glucose. To highlight the progress in the field of disease diagnostics using nanozyme, this review discusses many nanozyme-based detection methods categorized by the types of target biomolecules. Finally, we address the current challenges and perspectives for the widespread utilization of nanozyme-based disease diagnostics.

• 대한방사성의약품학회지
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• 제4권2호
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• pp.115-120
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• 2018

In recent years, many researchers have attempted to make use of 2D nanoparticles as molecular imaging probes since extensive investigations proved that 2D nanoparticles in the body tends to accumulate certain lesions by enhanced permeability and retention (EPR) effect. For example, graphene and carbon nitride which have high surface area and modifiable properties showed good biocompatibility and targetability when it used as imaging probes. However, poor dispersibility in physiological mediums and its uncontrolled size limited its usage in bio-application. Therefore, oxidation process and mechanical exfoliation have been developed for overcoming these problems. In this paper, we highlight the several major methods to synthesize biocompatible 2D nanomaterials like graphene and carbon nitride especially for molecular imaging study including positron emission tomography (PET).

• 한국건설순환자원학회논문집
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• 제7권2호
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• pp.174-186
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• 2019

This paper reviews the development condition of nanomaterials used in concrete over years. The definitions of nanomaterial, nanotechnology, and nano-concrete are reviewed. The impacts of nanomaterials on cementitious material in the point of advantages and disadvantages are analyzed. Moreover, this paper analyzes and classifies the nanomaterials into the extra quality enhancement and modification to plain cementitious composite. Indeed, the outstanding properties of the embedded nanomaterials can be introduced to concrete such as the mechanical improvement, pore structure refinement, hydrate acceleration, and smartness modifying of self-cleaning, and/or self-sensing. Before the full potential of nanotechnology can be realized in concrete applications, various techniques have to be solved including proper dispersion, compatibility of the nanomaterials in cement, processing, manufacturing, safety, handling issues, scale-up, cost, the impact on the environment and human health.

• 한국자기공명학회논문지
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• 제23권2호
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• pp.51-55
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• 2019

Quantum dot (QD) is an emerging novel nanomaterial that has wide applicability and superior functionality with relatively low cost. Nuclear magnetic resonance (NMR) spectroscopy has been contributed to elucidate various features of QDs and to improve their overall performance. In particular, NMR spectroscopy becomes an essential analytical tool to monitor and analyze organic ligands on the QD surface. In the present mini-review, application of NMR spectroscopy as a superb methodology to appreciate organic ligands is discussed. In addition, it was recently noted that ligands exert rather greater influence on diverse features of QDs than our initial anticipation, for which contribution of NMR spectroscopy is briefly reviewed.

• Composites Research
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• 제34권2호
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• pp.82-87
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• 2021

The mechanical properties of carbon fiber-reinforced epoxy composites (CFRPs) are greatly dependent on the interfacial adhesion between the carbon fibers and the epoxy matrix. Introducing nanomaterial reinforcements into the interface is an effective approach to enhance the interfacial adhesion of CFRPs. The main purpose of this work was to introduce graphitic nanofiber (GNFs) between an epoxy matrix and carbon fibers to enhance interfacial properties. The composites were reinforced with various concentrations of GNFs. For all of the fabricated composites, the optimum GNF content was found to be 0.6 wt%, which enhanced the interlaminar shear strength (ILSS) and fracture toughness (KIC) by 101.9% and 33.2%, respectively, compared with those of neat composites. In particular, we observed a direct linear relationship between ILSS and KIC through surface free energy. The related reinforcing mechanisms were also analyzed and the enhancements in mechanical properties are mainly attributed to the interfacial interlocking effect. Such an effort could accelerate the conversion of composites into high performance materials and provide fundamental understanding toward realizing the theoretical limits of interfacial adhesion and mechanical properties.

• 한국표면공학회지
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• 제55권6호
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• pp.308-318
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• 2022

The surface modification and treatment using thermal plasma were reviewed in academic fields. In general, thermal plasma is generated by direct current (DC) and radiofrequency (RF) power sources. Thermal spray coating, a typical commercial process using thermal plasma, is performed by DC thermal plasma, whereas other promising surface modifications have been reported and developed using RF thermal plasma. Beyond the thermal spray coating, physical and chemical surface modifications were attempted widely. Superhydrophobic surface treatment has a very high industrial demand particularly. Besides, RF thermal plasma system for large-area film surface treatment is being developed. Thermal plasma is especially suitable for the surface modification of low-dimensional nanomaterial (e.g., nanotubes) by utilizing high temperature and rapid quenching. It is able to synthesize and modify nanomaterials simultaneously in a one-pot process.

• Advances in nano research
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• 제11권6호
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• pp.641-648
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• 2021

In this article, the dynamic parameters (frequencies, mode shapes, damping ratios) of the scaled concrete structure and the dynamic parameters (frequencies, mode shapes, damping ratios) of the entire outer surface of titanium dioxide, 80 micron in thickness are compared using operational modal analysis method. Ambient excitation was provided from micro tremor ambient vibration data on ground level. Enhanced Frequency Domain Decomposition (EFDD) was used for the output only modal identification. From this study, a good correlation between mode shapes was found. Titanium dioxide applied to the entire outer surface of the scaled concrete structure has an average of 11.78% difference in frequency values and 10.15% in damping ratios, proving that nanomaterials can be used to increase rigidity in structures, in other words, for reinforcement. Another important result determined in the study was the observation of the adherence of titanium dioxide and similar nanomaterials mentioned in the introduction to concrete structure surfaces was at the highest level.