• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.195.2-195.2
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• 2014

Nanodiamond (ND) is composed of inner diamond core and outer graphite shell. The size of ND used in this study was about 5 nm. The ND solution was dropped on silicon substrate and dried in air. Dried ND sample was purified by using annealing method in air. Then, 40 keV Fe ion was irradiated into the sample. The dose was varied from $1{\times}10^{14}$ to $1{\times}10^{16}ions/cm^2$. The post annealing was performed at 1073 K in the vacuum to recover diamond structure. The annealing at 873 K in air was performed to remove the outer graphite shell. The structure of ND was confirmed by X-ray diffraction (XRD) and Raman spectroscopy. We will present the detailed data and results in the conference.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.177-181
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• 2009

Compositional gradient CrNx coatings were fabricated using arc ion plating in Ar/$N_2$ gaseous mixture by gradually increasing $N_2$ flux rate from 0 to 120 SCCM. The effect of negative substrate bias on the film microstructure and mechanical properties were systematically investigated with XRD, GDOES, and SEM. The results show that substrate bias has an important influence on film growth and microstructure of gradient CrNx coatings. The coatings mainly crystallized in the mixture of hexagonal $Cr_{2}N$ and fcc CrN phases. By increasing substrate bias, film microstructure evolved from an apparent columnar structure to an equiaxed one. With increasing substrate bias, deposition rate first increased, and then decreased. The maximum of deposition rate was 15 nm/min obtained at a bias of -50V.

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.157-157
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• 1999

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1409-1412
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• 2012

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2607-2610
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• 2011

Monodispersed Ag/$TiO_2$ core/shell nanoparticles were synthesized in solution via colloid-seeded deposition process using Ag nanoparticles as colloid seeds and $Ti(SO_4)_2$ as Ti-source respectively. Silver nitrate was reduced to Ag nanoparticles with $N_2H_4{\cdot}H_2O$ in the presence of CTAB as stabilizing agent. The titania sols hydrolyzed by the $Ti(SO_4)_2$ solution deposited on the surface of Ag nanoparticles to form the Ag/$TiO_2$ core/shell nanoparticles. Inductively coupled plasma atomic emission spectrometry (ICP-AES) showed low amount of Ag ion leaching from the Ag/$TiO_2$ core/shell nanoparticles. The Ag/$TiO_2$ core/shell nanoparticles indicated excellent antibacterial effects against Escherichia coli and maintained long-term antibacterial property.

• 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.

• 한국디지털정책학회:학술대회논문집
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• 2007.06a
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• pp.325-332
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• 2007

The purpose of this study is to get a politic advanced idea to operate a pro-environment based u-city through the overcome problems on the construction policy for the even areal distribution, and the development for the model structure of the high level. Advanced pro-environmental ubiquitous urban construction becomes an example of the practical level linked by the national agenda as uKorea policy. The Idea of the national land informal ion systems transforms to enhance or to guide the national strategic industry to implement balanced development as grand objectives of the national land due to the factor that 'the economic development 5 years plan' altered to 'the national land 5 years plan'. Therefore, ubiquitous echo city construct ion becomes realized as static spatial informal ion construct ion and dynamic mobile based ubiquitous lives operable by the information infrastructure and IT839 policy items operation. For the synergy effects through this task, it requires a strong empowerment of the information industries and a new growing core engine of the national economy through the policy of the mutual satisfaction on the spat io-temporal information and the pro-environment information systems.

• Applied Microscopy
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• v.45 no.4
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• pp.236-241
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• 2015

Carbon-coated Ni, Cu and Sn nanocapsules were investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM) and a four-point probe device. All of these nanocapsules were prepared by an arc-discharge method, in which the bulk metals were evaporated under methane ($CH_4$) atmosphere. Three pure metals (Ni, Cu, Sn) were typically diverse in formation of the carbon encapsulated nanoparticles and their different mechanisms were investigated. It was indicated that a thick carbon layers formed on the surface of Ni(C) nanocapsules, whereas a thin shell of carbon with 1~2 layers covered on Cu(C) nanocapsules, and the Sn(C) nanocapsules was, in fact, a longger multi-walled carbon nanotubes partially-filled with metal Sn. As one typical magnetic/dielectric nanocomposite particles, Ni(C) nanocapsules and its counterpart of oxide-coated Ni(O) nanocapsules were compared in the electrically conductive behaviors for further applications as the electromagnetic materials.

• Clean Technology
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• v.27 no.2
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• pp.115-123
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• 2021

This study demonstrates a new method for the synthesis of organic-inorganic hybrid particles composed of an inorganic silica shell and organic core particles. The organic core particles are prepared with a uniform size using droplet-based microfluidic technology. In the process of preparing the organic core particles, uniform droplets are generated by independently controlling the flow rates of the dispersed phase containing photocurable resins and the continuous phase. After the generation of droplets in a microfluidic device, the droplets are photo-polymerized as particles by ultraviolet irradiation at the ends of microfluidic channels. The core particle is coated with a nano complex composed of polyallylamine hydrochloride (PAH) and phosphate ion (Pi) through strong non-covalent interactions such as hydrogen bonding and electrostatic interaction under optimized pH conditions. The polyamine nano complex rapidly induces the condensation reaction of silicic acid through the arranged amine groups of the main chain of PAH. Therefore, this method enabled the preparation of organic-inorganic hybrid particles coated with inorganic silica nanoparticles on the organic core. Finally, we demonstrated the synthesis of organic-inorganic hybrid particles in a short time under ambient and environmentally friendly conditions, and this is applicable to the production of organic-inorganic hybrid particles having various sizes and shapes.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.294-305
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• 2015

We have quantitatively analyzed 1,294 effective patents on "Quantitative Analysis of Patents Concerning Cathode Active Materials for Lithium-Ion Secondary Batteries Based on Layer Structure" from Korea, USA, Japan, Europe and PCT (WO). The importance of technological and patent values of the aforesaid patents were evaluated by the factors shown in Table 1, and 104 major and 20 core patents were selected in compliance with the evaluation from the patents. The technological flow chart over time regarding the selected major and core patents was prepared, and the applying time and development process of patents, as well as the position of core patents were established on the time scale investigated. Finally, the differentiation plans and patent avoidance strategies for the next technology development, in comparison with the technologies of patents already applied and registered, were suggested.