• 대한핵의학회:학술대회논문집
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• 1975.06a
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• pp.87.1-87.1
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• 1975

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.2
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• pp.101-105
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• 2006

Nanoscale floating-gate characteristic of colloidal Au nanoparticles electrostatically assembled on the oxidized surface of Si nanowires have been investigated. The Si nanowire split-gate transistor structure was fabricated by electron beam lithography and subsequent reactive ion etching. Colloidal Au nanoparticles with ${\sim}5$ nm diameters were selectively deposited onto the Si nanowire surface by 2 min electrophoresis. It was found that electric fields applied to the self-aligned split side gates allowed charge to be transferred on the Au nanoparticles. It was observed that the depletion mode cutoff voltage, induced by the self-aligned side gates, was shifted by more than 1 V after Au nanoparticle electrophoresis. This may be due to the semi-one dimensional nature of the narrow Si nanowire transport channel, having much enhanced sensitivity to charges on the surface.

• The Korean Journal of Nuclear Medicine
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• v.7 no.1
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• pp.39-43
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• 1973

The bone marrow scans with colloidal $^{198}Au$ were performed on 33 cases with hematologically normal patients and patients with various blood dyscrasia. Bone marrow aspirations were done at iliac crest in all cases but one. A correlation between the scan findings and an erythroid cellularity was evaluated. The following results were obtained. 1) Out of 33 cases, 23 (about 70%) showed a correlation between $^{198}Au$ marrow uptakes on the scans and the erythroid cellularity. 2) The diseases in which no correlation existed between $^{198}Au$ uptake and erythroid cellularity were aplastic anemia, acute leukemia and chronic myelogenous leukemia.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.1-7
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• 1999

Metal colloidal particles have been prepared by a photo-chemical process in an aqueous solution containing semiconductor nanocrystallites. Metal colloidal particles produced in CdS and AgBr exhibit different absorption spectra. Au particles produced in solution with CdS show typical Au plasmon resonance absorption spectra. On the other hand Ag particles in solution with AgBr shows surface plasmon resonance absorption spectra which are red-shifted, as compared to that of a dispersion of homogeneous Ag colloidal particles in the same host. The extent of red-shift depends on the UV illumination time. This phenomenon is interpreted within the context of effective medium theory for small volume fractions. From the theory, a metal coated particle predicts Ag plasmon resonance, red shifted with respect to 400 nm that would be associated with a silver particle in solution. The absorption peak position is very sensitive to the coating thickness.

• Korean Journal of Materials Research
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• v.11 no.7
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• pp.569-574
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• 2001

The crystal structure, surface morphology and preferred orientation of the copper electrodeposit were investigated by the using sulfate bath with $SiO_2$suspensions and the cathode substrate Au sputtered. As by the addition of colloidal silica in copper electrolytic bath and Au pre-coating on substrate, the crystal particles of deposits was fined-down, made uniform and the account of particles were increased. Hardness of copper electrodeposits with colloidal silica increased about 15% in comparison with that of pure copper deposit film and (111), (200) and (311) plane of X-ray diffraction patterns were almost swept away, so preferred orientation of the copper deposits changed from (111) to (110) plane by codeposit $SiO_2$ and precoating the substrate.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1637-1640
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• 2009

• 대한핵의학회:학술대회논문집
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• 1966.11a
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• pp.93.3-94
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• 1966

The fact that colloidal particulates of rdaiogold are mainly and effectively eliminated from the blood stream by phagocytic activity of Kupffer's cells of the liver has been successfully adopted to the diagnosis if certain liver diseases and the same principle has opened a new avenue to the study of the organ by obtaining scan. Indeed, the latter procedure has been widely used for the detection of space-occupying lesions of cirrhosis of the liver. Nevertheless problem of differential diagnosis of monochromatic "cold" areas or "mottling" of the internal structure on the scan limited the value of this diagnostic modality. The present investigation is aimed at improving intepretation of photoscan findings with the aid of blood clearance rate of the intravenously injected colloidal $^{198}Au$.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.188-196
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• 2013

We have investigated the effects of formalin on the assembly of colloidal gold nanoparticles (AuNPs) prepared by laser ablation of a solid gold target in deionized water. Upon addition of formalin, the surface plasmon resonance (SPR) band at 519 nm for pure AuNPs decreases and shifts to red while a new broad SPR band appears at ~700 nm. The red-shift is prominent with increase in the incubation time. The average size of the initial AuNPs is around 12 nm but it increases to 23 nm after addition of formalin. It turns out that formalin acts as a cationic surfactant for AuNPs with negative surface charge in the colloidal solutions. Furthermore, through analysis of the Raman spectrum of formalin and the density functional theory calculations, we confirm that methanediol is the main species in formalin which is in charge of the aggregation of AuNPs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.107-108
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• 2005

Au and $Au/SiO_2$ nanoparticles(NPs) were synthesized by the colloidal method. The formation of Au and $Au/SiO_2$ NPs was confirmed using high resolution transmission electron microscopy (HRTEM). Synthesized solutions were deposited on Si wafer. The electrical properties of structures were measured using a semiconductor analyzer and a LCR meter. Capacitance versus voltage hysterisis curves showed the charge storage effect by Au and $Au/SiO_2$ NPs.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.365-370
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• 2014

For real-time monitoring of colloidal nanoparticles (NPs) in aqueous media, a light sheet type dark-field microscopy system combined with a microfluidic concentration gradient generator (${\mu}FCGG$-LSDFM) was developed. Various concentrations of colloidal Au NPs were simultaneously generated with the iFCGG and characterized with the LSDFM setup. The number concentrations and hydrodynamic size distributions were measured via particle counting and tracking analysis (PCA and PTA, respectively) approaches. For the 30 nm Au NPs used in this study, the lower detection limit of the LSDFM setup was 3.6 ng/mL, which is about 400 times better than that of optical density measurements under the same ${\mu}FCGG$ system. Additionally, the hydrodynamic diameter distribution of Au NPs was estimated as $39.7{\pm}12.2nm$ with the PTA approach, which agrees well with DLS measurement as well as the manufacturer's specification. We propose this ${\mu}FCGG$-LSDFM setup with features of automatic generation of NP concentration gradient and real-time monitoring of their physicochemical characteristics (e.g., number concentration, and hydrodynamic size distribution) as an important component of future high-throughput screening or high-content analysis platforms of nanotoxicity.