• Proceedings of the Korean Vacuum Society Conference
• /
• 2015.08a
• /
• pp.150.2-150.2
• /
• 2015

In this study, we analyzed the electric and optical characteristics by using various deposition rate ($0.5{\AA}$, $1.0{\AA}$ and $1.5{\AA}/s$) in order to enhance the performance in organic light-emitting devices (OLED). The organic multi-layer structures were deposited with NPB ($500{\AA}$ as hole transport layer), Alq3 ($600{\AA}$ as electron transport layer and emission layer) and LiF ($8{\AA}$ as electron injection layer) via SUNIC PLUS200 on Glass/ITO substrates. In this experiment, we examined the relationship between porous state of organic deposition and mobility of the organic materials. Among the three deposition rates, $0.5{\AA}/s$ achieved the highest performance of (10,786cd/m2, 4.387cd/A) comparing with that of $1{\AA}/s$ (7,779cd/m2, 3.281cd/A) and $1.5{\AA}/s$ (5,167cd/m2, 2.693cd/A). We confirmed that low deposition rate helps to arrange organic materials densely and to move easily another atomic location using inter-chain transporting by orbital overlap.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.30 no.3
• /
• pp.185-191
• /
• 2017

Cadmium compounds with one dimension (1D) nanostructures have attracted attention for their excellent electrical and optical properties. In this study, vertically aligned CdTe-Si nanostructures with high density were synthesized by several simple chemical reactions. First, l D Te nanostructures were synthesized by silver assisted chemical Si wafer etching followed by a galvanic displacement reaction of the etched Si nanowires. Nanowire length was controlled from 1 to $25{\mu}m$ by adjusting etching time. The Si nanowire galvanic displacement reaction in $HTeO_2{^+}$ electrolyte created hybrid 1D Te-branched Si nanostructures. The sequential topochemical reaction resulted in $Ag_2Te-Si$ nanostructures, and the cation exchange reaction with the hybrid 1D Te-branched Si nanostructures resulted in CdTe-Si nanostructures. Wet chemical processes including metal assisted etching, galvanic displacement, topochemical and cation exchange reactions are proposed as simple routes to fabricate large scale, vertically aligned CdTe-Si hybrid nanostructures with high density.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.4
• /
• pp.315-320
• /
• 2013

The composites composed of conducting polymer (MEH-PPV), CdTe nanoparticles, and multiwalled carbon nanotubes (MWNTs) were spectroscopically and electrically characterized in their thin films. The composite films were prepared by spray coating. These composites were prepared from the mixture solution of MEH-PPV and CdTe-embedded MWNTs, in which CdTe nanoparticles were electrostatically bound to MWNTs. UV/vis and PL spectra were analyzed to investigate the optical absorbance and emission of the composite films. In addition, their structural, electrochemical, and electrical properties were studied by transmission electron microscopy, cyclic voltammetry, and I-V measurement.

• The Korean Journal of Physiology and Pharmacology
• /
• v.10 no.3
• /
• pp.137-141
• /
• 2006

The systolic and diastolic pressures in anesthetized Sprague-Dawley male rats were greatly decreased after single-dose of Cd treatment without significant changes in heart rate. There was a fluid-shift into the third space and/or -loss through the kidney, since plasma $Na^+$ concentration and hematocrit ratio were significantly increased by acute Cd exposure. The present study showed that the sustained hypotensive effect of single-dose Cd on the cardiovascular system might have resulted from the systemic hypovolemia. Furthermore, renal excretion of electrolytes, including $Na^+$ and $K^+$, and urine flow rate were increased by Cd intoxication. Interestingly, the ratio of $Na^+/K^+$ excretion was increased and reached the maximum level 3 hours after Cd injection and returned to the normal level after 7 hours. Nevertheless, there was no difference in the regression analysis of $Na^+$ excretion and urine flow rate in both groups. Therefore, the increase in the urine volume seemed to enhance the excretion of $Na^+$. This study strongly suggest that the hypotensive effect of Cd is mediated by systemic $Na^+$ loss through the kidney and/or hypovolemia via fluid-shift.

• Progress in Superconductivity and Cryogenics
• /
• v.17 no.3
• /
• pp.5-8
• /
• 2015

The effects of Pr substitution on the structural and the superconducting properties for Pb-based 1201 cuprates with compositions of $(Pb_{0.5-x}Pr_xCd_{0.5})SrLaCuO_z(0{\leq}x{\leq}0.25)$ and $(Pb_{0.45}Pr_{0.05}Cd_{0.5})(Sr_{1-y}La_{1+y})CuO_z(0{\leq}y{\leq}0.1)$ were investigated. It is found that $T_c$ decreases as the Pr-doping content x increases in the $(Pb_{0.5-x}Pr_xCd_{0.5})SrLaCuO_z$ samples, whereas $T_c$ of $(Pb_{0.45}Pr_{0.05}Cd_{0.5})(Sr_{1-y}La_{1+y})CuO_z$ samples increases as the La-doping content y increases. The experimental results were discussed in connection with the change in hole concentration of the samples.

• Journal of the Korean Ceramic Society
• /
• v.47 no.2
• /
• pp.189-194
• /
• 2010

Compared with organic fluorophores, semiconductor quantum dots (QDs) have the better properties such as photostability, narrow emission spectra coupled to tunable photoluminescent emissions and exceptional resistance to both photo bleaching and chemical degradation. In this work, CdSe/ZnS QDs nanobeads were prepared by the incorporation of CdSe/ZnS QDs with mesoporous silica to use as the optical probe for detecting toxic and bio- materials with high sensitivity, CdSe/ZnS core/shell QDs were synthesized from the precursors such as CdO and zinc stearate with the lower toxicity than pyrotic precursors. The QD-nanobeads were characterized by transmission electron microscopy, FL microscopy, UV-Vis and PL spectroscopy, respectively.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.351-354
• /
• 2006

We developed highly efficient fluorescent dopants for full-color OLEDs. For blue, green and red OLEDs, current efficiencies of 8.7cd/A, 20.5 cd/A and 11.4 cd/A at $10mA/cm^2$ were achieved, respectively. Lifetime of the blue device was estimated to be 23,000hours at an initial luminance of $1,000cd/m^2$. Moreover, long lifetime over 100,000 hours was estimated in the green and red devices. Furthermore, we obtained a three-component white OLED by using these new fluorescent materials. This white OLED shows a current efficiency of 16.1cd/A with extrapolated lifetime over 70,000 hours at $1,000cd/m^2$, and more excellent color reproducibility for full-color displays with color filters and general lighting, compared to previous fluorescent white OLEDs.

• Journal of Electrochemical Science and Technology
• /
• v.5 no.4
• /
• pp.115-127
• /
• 2014

Cd-Pb thin films were electrodeposited from a diluted chloride solution using stainless steel rotating disc electrode. The linear sweep voltammograms of the single metallic ions show that electrodeposition of these ions was mass transfer control due to the plateau observed for different rotations at concentration (50 and 200 ppm). The voltammograms of binary system elucidate that electrodeposition process always start at cathodic potential located between the potential of individual metals. Currents transients measurements, anodic linear sweep voltammetry (ALSV) and atomic force microscopy (AFM) were used to characterize the electrocryatalization process and morphology of thin films. ALSV profiles show a differentiation for the dissolution process of individual metals and binary system. Two peaks of dissolution Cd-Pb film were observed for the binary system with different metal ion concentration ratios. The model of Scharifker and Hills was used to analyze the current transients and it revealed that Cd-Pb electrocrystalization processes at low concentration is governed by three-dimensional progressive nucleation controlled by diffusion, while at higher concentration starts as a progressive nucleation then switch to instantaneous nucleation process. AFM images reveal that Cd-Pb film electrodeposited at low concentration is more roughness than Cd-Pb film electrodeposited at high concentrated solution.

• Journal of Yeungnam Medical Science
• /
• v.21 no.2
• /
• pp.237-241
• /
• 2004

Hairy cell leukemia (HCL) is an uncommon chronic B-cell lymphoproliferative disorder that is characterized by cytopenia, splenomegaly, and mononuclear cells displaying cytoplasmic projections. We experienced a case of hairy cell leukemia that developed in a 38-year-old man. He showed marked splenomegaly without palpable lymphoadenopathy. A complete blood cell count revealed leukopenia ($3300/{\mu}{\ell}$ with 63% of lymphocyte) and the peripheral blood smear showed abnormal lymphoid cells with cytoplasmic projections. The bone marrow smear revealed abnormal lymphocytes and severe myelofibrosis. Tartrate-resistant acid phosphatase reactivity was strongly positive in the hairy cells. The immunophenotyping results of lymphoid cells were CD5(-), CD10(-), CD19(+), CD25(+), CD103(+), CD20(+), lambda(+). The patient was treated with 2-Chlorodeoxyadenosine at a daily dose of 0.1mg/Kg by a continuous intravenous infusion for 7 days. The patient achieved complete remission.

• Advances in Traditional Medicine
• /
• v.3 no.2
• /
• pp.90-99
• /
• 2003

There are several data in the literature indicating a great variety of pharmacological activities of Polypodium genus, which exhibit antiinflammatory and immunomodulatory activities. Since one of our main interests is to obtain natural immunoregulatory agents devoid of pharmacological adverse effects, we used flow cytometry analysis to highlight relative contributions of a water-soluble fraction of different concentrations of Polypodium rhizome extracts on lymphocyte subpopulations, NK and LAK activity. To measure their potential immunoregulatory activity a T cell proliferation assay in response to phytohemaglutinin (PHA) and mixed lymphocyte reactions were chosen. As a confirmatory bioassay we studied the effect of our extracts on CD45RO and CD95 antigen expressions. The results indicate that CD95 expression dramatically increases after peripheral blood lymphocyte activation and treatment with Polypodium leucotomus, cambricum and vulgare extracts, suggesting a powerful intrinsic pro-apoptotic effect.