• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.456-456
• /
• 2008

In the past few years, the deposition and characterization of cadmium sulfide semiconducting thin films has received a considerable amount of interest due to their potential application in the area of electronic and opto-electronic devices fabrications. Polycrystalline CdS thin films posses good optical transmittance, wide band-gap and electrical properties makes it as one of the ideal material for their application to solar cell fabrication. Cadmium sulfate thin films were deposited by the chemical bath deposition method using tartaric acid and triethanolamine as a complexing agent. Deposition parameters such as pH, temperature, deposition time and concentration of the reactant species were optimized so as to obtain reflecting, good adherent uniform thin films on the glass substrate. Reaction mechanism of the thin film formation is also reported. The crystallographic structure and the crystallite size were studied by the X-ray diffraction pattern. The optical band-gap of deposited film is identified by measuring the transmittance in the visible region. Temperature dependence of resistivity confirmed the semiconducting behavior of the film. Scanning electron micrographs (SEM) showed the presence of grain particles of size 50 nm.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.23 no.2
• /
• pp.457-463
• /
• 2009

This study aimed to evaluate the anti-asthmatic effects of Seonpye-tang (SPT) using OVA-induced asthmatic mice model. Scavenging activity of SPT on DPPH free radical and SOD-like activity of SPT were measured at final concentration 62.5, 125, 250, 500 (${\mu}g/m{\ell}$), RBL-2H3 cells were treated with DNP IgE for 24hr, and treated with SPT (1, 10, 100 ${\mu}g/m{\ell}$) for 1hr, followed by treatment with DNP-HSA for 1hr at $37^{\circ}C$. The level of IL-4 and TNF-${\alpha}$ were measured by ELISA. Asthmatic mice model was conducted by repeated challenge of OVA using C57BL/6 mice. Each group was treated with distilled water, SPT (400 mg/kg and 200 mg/kg) extract or cyclosporin A (10 mg/kg) for the later 8 weeks. Immune cells subpopulation, eotaxin, IL-5 and TNF-${\alpha}$ in BALF were analyzed. SPT dose-dependently increased Scavenging activity on DPPH free radical and SOD-like activity. SPT significantly ameliorated the increase of total cells number and eosinophil including of immune cell subpopulation of $CD3^+/CD69^+$, $CCR3^+$, $B220^+/CD22^+$, $B220^+/CD45^+$ and $B220^+/IgE^+$ cells in BALF comparing to control group. Eotaxin and IL-5 level in BALF were significantly decreased by SPT. These results strongly suggest that SPT would be a effective candidate for herbal-originated anti-asthmatic drug. However, this drug should be further studied for characterization of the accurate action and underlying mechanisms using variant disease model in the future.

• Clinical and Experimental Reproductive Medicine
• /
• v.24 no.1
• /
• pp.67-81
• /
• 1997

To determine the concentration and the physiologic role of metal components in blood plasma and seminal plasma in relation to male infertility, the concentrations of twelve metal components in blood plasma and seminal plasma including Na, Mg, K, Ca, Cr, Mn, Fe, Cu, Zn, Se, Cd and Pb were measured by atomic absorbance spectrophotometery or ion selective electrode analysis. Semen and blood samples were obtained from a total of 110 men including 70 male infertility patients, 20 vasectomized persons and 20 fertility proven volunteers visited to the Male Infertility Clinic of Pusan National University Hospital. The concentrations of Ca, Zn, Mg, Cr and Cd in control group were higher in seminal plasma than in blood plasma, and additionally Pb were higher in infertility group. The concentrations of all metal components revealed no significant difference according to patients' age, resident, occupation, sperm density, motility and hormone level in blood plasma, but some metal components including Ca, Mg, Cu, Mn, Cd and Pb revealed a significant difference according to each these parameters except patient's age in seminal plasma. The concentrations of Mn, Cd and Pb in the vasectomy persons were higher than in the infertility group III including testicular and epididymal factors, but not in blood plasma. We conclude that the quantitative changes of metal components in the seminal plasma may have effects on not only spermatogenesis and sperm function, but also contribute to diagnostic parameter according to organ specificity of the metal in the male reproduction.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.8
• /
• pp.2487-2493
• /
• 2014

Dimeric ${\beta}$-cyclodextrin linked by a thioether bridge was synthesized from a reaction of mono-6-iodo-6-deoxy-${\beta}$-cyclodextrin with sodium sulfide, and the structure was analyzed using nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The effects of thioether-bridged dimeric ${\beta}$-CD on the aqueous solubility of flavonols (myricetin, quercetin, and kaempferol) were investigated by ultraviolet-visible spectroscopy. The aqueous solubility of myricetin, quercetin, and kaempferol were enhanced 33.6-, 12.4-, and 10.5-fold following the addition of 9 mM of thioether-bridged dimeric ${\beta}$-CD. In comparison, the aqueous solubility of myricetin, quercetin, and kaempferol were enhanced 5.4-, 3.3-, and 2.7-fold using the same concentration of monomeric ${\beta}$-cyclodextrin. Furthermore, the formation of flavonol/thioether-bridged dimeric ${\beta}$-CD inclusion complexes was confirmed with nuclear magnetic resonance, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The results showed that the nature of the complexes significantly differed from that of free flavonols. Herein, we suggest that the thioether-bridged dimeric ${\beta}$-CD can act as an effective complexing agent for flavonols.

• Korean Journal of Materials Research
• /
• v.9 no.2
• /
• pp.173-180
• /
• 1999

Thermally evaporated ZnTe films were investigated as a back contact material for CdS/CdTe solar cells. Two deposition methods, coevaporation and double-layer methods, were used for Cu doping in ZnTe films. ZnTe layers (0.2$\mu\textrm{m}$ thick) were deposited either on glass or on CdS/CdTe substrates without intentional heating of the substrates. Post-deposition annealing was performed at 200,300 and $400^{\circ}C$ for 3,6 and 9 minutes, respectively. Band gap of 2.2eV was measured for both undoped and doped films and a slight change in the shape of absorption spectra was observed in Cu-doped samples after annealing at $400^{\circ}C$. The resistivity of as-deposited ZnTe decreased from 10\ulcorner~10\ulcornerΩcm down to 10\ulcornerΩcm as Cu concentration increased from 0 to 14 at.%. There was not a noticeable change in less of annealing temperature up to $300^{\circ}C$ whereas films annealed at $400^{\circ}C$ revealed hexagonal (101) orientations as well. Some of Cu-doped ZnTe revealed x-ray diffraction (XRD) peaks related with Cu\ulcornerTe(x=1.75~2). Grain growth was observed from about 20nm in as-deposited films to 50nm after annealing at $400^{\circ}C$ by scanning electron microscopy (SEM). Cu distribution in ZnTe films was not uniform according to Auger electron spectroscopy (AES) measurements.

• Korean Journal of Weed Science
• /
• v.16 no.4
• /
• pp.346-353
• /
• 1996

To study the effects of metal ions on the activities of antioxidative enzymes, the activities of superoxide dismutase(SOD), peroxidase(POD), catalase(CAT) of Persicaria vulgaris has been studied after treating with Cd, Cu, Zn and Al. 1. The activities of SOD in leaf and stem were decreased, but that in root was increased. Among the metal ions studied in this report, Al gave the highest increase in SOD activity in root. 2. The activities of POD after treating with Cd or Cu did not show any significant differences. POD activities after treating with Zn and Al has been decreased, however, that in root showed increased activities after treating with Zn 5,000 ppm or Al 500 ppm. 3. The activity of CAT in leaf was decreased with every metals studied. The CAT activity in root was increased with increased concentration. The root treated with Al showed highest activity. 4. The presence of isozymes after treated metal ions has been studied in gel electrophoresis. The POD treated plant did not show any new isozymes, but the intensity of one of pre-existent band was increased. The SOD treated plant showed the several new isozymes.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.4
• /
• pp.922-927
• /
• 2005

In the present study, baicalin, baicalein, and wogonin, a major flavone isolated from Scutellaria Radix were examined for their effects on PMA-induced Interlukin-6 (IL-6), $interferon-\gamma(IFN-\gamma)$, tumor necrosis factor $(TNF)-\alpha$, IL-4, IL-10, and IL-13 productions in the PMA-stimulated $CD4^+$ Jurkat T cells. These three compounds inhibited PMA-induced Th1 cytokine $(IL-6,\;IFN-\gamma,\;TNF-\alpha)$ and Th2 cytokine (IL-4 and IL-13) productions in a concentration-dependent manner. But wogonin, but not baicalin baicalein, increased PMA-induced IL-10 production. These results suggest that baicalin, baicalein, and wogonin, a major flavone modulate Th1 and Th2 cytokine productions in $CD4^+$ Jurkat T cells and these properties may contribute to the anti-atopic dermatitis activity of Scutellaria Radix.

• Applied Biological Chemistry
• /
• v.33 no.2
• /
• pp.138-142
• /
• 1990

The effects of heavy metals Cd, Cu, Cr, Ni, and Zn on the degradation of the insecticide fenitrothion (O, O-dimethyl O-4-nitro-m-tolyl phosphorothioate), the fungicide IBP (5-benzyl O, O-diisopropyl phosphorothioate), and the herbicide butachlor (N-butoxymetyl-2-chloro-2', 6'-diethylacetanilide) in flooded soils were examined in the laboratory. The degradation of the 3 pesticides in soil was greatly inhibited by the amendment of the 5 heavy metals. The inhibition rate was high in the order of butachlor>IBP>fenitrothion. Populations of fenitrothion-and butachlor-degrading microbes, which were counted by the MPN method, were lower in heavy metals added soil than in the control soil. The effect of heavy metals on the degradation of the 3 pesticides in soil varied with the kind and concentration of heavy metals and the kind of pesticides.

• Korean Journal of Materials Research
• /
• v.30 no.9
• /
• pp.447-452
• /
• 2020

In this work, α-Fe₂O₃ nanocrystals are synthesized by co-precipitation method and used as adsorbent to remove Cr⁶⁺, Cd²⁺, and Pb²⁺ from wastewater at room temperature. The prepared sample is evaluated by XRD, BET surface area, and FESEM for structural and morphological characteristics. XRD patterns confirm the formation of a pure hematite structure of average particle size of ~ 40 nm, which is further supported by the FESEM images of the nanocrystals. The nanocrystals are found to have BET specific surface area of ~ 39.18 m² g^-1. Adsorption experiments are carried out for the different values of pH of the solutions, contact time, and initial concentration of metal ions. High efficiency Cr⁶⁺, Cd²⁺, and Pb²⁺ removal occur at pH 3, 7, and 5.5, respectively. Equilibrium study reveals that the heavy metal ion adsorption of the α-Fe₂O₃ nanocrystals followed Langmuir and Freundlich isotherm models. The Cr⁶⁺, Cd²⁺, and Pb²⁺ adsorption equilibrium data are best fitted to the Langmuir model. The maximum adsorption capacities of α-Fe₂O₃ nanocrystals related to Cr⁶⁺, Cd²⁺, and Pb²⁺ are found to be 15.15, 11.63, and 20 mg g^-1, respectively. These results clearly suggest that the synthesized α-Fe₂O₃ nanocrystals can be considered as potential nano-adsorbents for future environmental and health related applications.

• Animal cells and systems
• /
• v.10 no.4
• /
• pp.211-217
• /
• 2006

Heavy metals are well known as important environmental pollutants and also considered as endocrine disrupters. This study was performed to evaluate the direct effects of heavy metals such as cadmium (Cd), zinc (Zn), mercury (Hg), lead (Pb), cobalt (Co), and arsenic (As) on the various steroidogenic enzymes in frog ovarian follicles. Ovarian follicles from Rana catesbeiana were isolated and cultured for 18 hours in the presence of frog pituitary homogenate (FPH, 0.05 gland/ml) or various steroid precursors with or without heavy metals (0.01-100 ${\mu}M$), and steroid levels in the follicle or culture medium were measured by radioimmunoassay (RIA). Thus, the steroidogenic enzyme activities were indirectly evaluated by measuring the converted steroid levels from the added precursor steroid. Among heavy metals, Hg, Cd and Zn significantly inhibited FPH-induced pregnenolone ($P_5$) production by the follicles ($EC_{50},\;4.0{\mu}M,\;25.6{\mu}M\;and\;5.7{\mu}M$, respectively ), and also suppressed the conversion of testosterone (T) to estradiol $17{beta}\;(E_2)\;(EC_{50},\;4.2{\mu}M,\;7.5{\mu}M\;and\;80.0{\mu}M) while Pb, Co and As are not or less effective in the inhibition. Other enzymes such as $C_{17-20}$ lyase and $17{\beta}$-hydroxysteroid dehydrogenase ($17{\beta}$-HSD) were suppressed only in the high concentration of Hg, Cd and Zn. Taken together, these data demonstrate that cytochrome P450 side chain cleavage (P450scc) and aromatase are much more sensitive to heavy metals than other steroidogenic enzymes and Hg, Cd and Zn show stronger toxicity to follicles than other heavy metals examined.