• The Korean Journal of Physiology and Pharmacology
• /
• v.6 no.1
• /
• pp.21-26
• /
• 2002

Effects of cadmium (Cd) intoxication on renal endosomal accumulation of organic cations $(OC^+)$ were studied in rats using $^{14}C-tetraethylammnium$ (TEA) as a substrate. Cd intoxication was induced by s.c. injections of 2 mg Cd/kg/day for $2{\sim}3$ weeks. Renal cortical endosomes were isolated and the endosomal acidification (acridine orange fluorescence change) and TEA uptake (Millipore filtration technique) were assessed. The TEA uptake was an uphill transport mediated by $H^+/OC^+$ antiporter driven by the pH gradient established by $H^+-ATPase.$ In endosomes of Cd-intoxicated rats, the ATP-dependent TEA uptake was markedly attenuated due to inhibition of endosomal acidification as well as $H^+/TEA$ antiport. In kinetic analysis of $H^+/TEA$ antiport, Vmax was reduced and Km was increased in the Cd group. Inhibition of $H^+/TEA$ antiport was also observed in normal endosomes directly exposed to free Cd (but not Cd-metallothionein complex, CdMt) in vitro. These data suggest that during chronic Cd exposure, free Cd ions liberated by lysosomal degradation of CdMt in proximal tubule cells may impair the endosomal accumulation of $OC^+$ by directly inhibiting the $H^+/OC^+$ antiporter activity and indirectly by reducing the intravesicular acidification, the driving force for $H^+/OC^+$ exchange.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.16 no.5
• /
• pp.690-702
• /
• 2013

Ionic liquids(ILs) have been the most investigated chemicals among green solvents including water, glycerol, supercritical carbon dioxdie($scCO_2$). ILs are attracting organic as well as inorganic chemicals because most ionic liquids' vapor pressures are very low so that ILs are liquids phase at ambient conditions. ILs are composed of various anions and cations, thus chemists can design functionalized solvents and/or catalysts that can be used in specific synthetic reactions by means of combinations of different ions. Many scientists believe ILs being green materials because of its low vapor pressure as well as the flexibility in controlling the chemical and physical properties. In this review the author describes recent development of ILs focused on imidazolium and pyridinium ILs which are being most investigated presently. In order to apply this materials in industrial level, the toxicity matter must be resolved first. In this regard, the author describes recent research trend regarding environmental effects by ILs as well as some meaningful results as well.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.1
• /
• pp.24-31
• /
• 2010

This study was carried out to analyze vegetation and soil characteristic, and ordination of Scrophularia takesimensis population, Ulleung Island. The Scrophularia takesimensis population was classified into Aster spathulifolius for. oharai dominant population, Vitis amurensis dominant population and Scrophularia takesimensis typical population. The Scrophularia takesimensis population was located in elevation of 1m to 6m, in Ulleung Island. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable potassium, exchangeable calcium, exchangeable magnesium and exchangeable sodium concentration, and cation exchange capacity, and soil pH were 9.1~19.1%, 0.19~0.52%, 87.1~196.7mg/kg, 2.0~2.8cmol+/kg, 5.4~5.9cmol+/kg, 5.9~8.8cmol+/kg, 4.4~4.8cmol+/kg, 20.3~26.7cmol+/kg, and 6.8~8.0, respectively. The Vitis amurensis dominant population was mainly found in the high percentage of total nitrogen, organic matter, CEC in comparison with Aster spathulifolius for. oharai dominant population.

• Asian-Australasian Journal of Animal Sciences
• /
• v.5 no.1
• /
• pp.113-121
• /
• 1992

An the livestock production in Japan is industrialized, a tremendous amount of animal wastes is being produced annually, resulting in serious environmental pollution problems. Animal wastes could be pollutants, but they are also important sources of fertilizer nutrients and organic matter. Composting is an effective way of promoting the increased utilization of animal wastes. The characterization of maturing process during composting is important in order to improve the composting technology and to develop and efficient method to estimate the degree of maturity. The rise and fall in temperature, and changes in the constituents of the compost, reflect the maturing process and may serve as indicators for maturation. In addition, the detection of nitrate by diphenylamine, the determination of cation-exchange capacity (CEC), and the germination test, are also recommended as the methods of estimating the degree of maturity. The heavy applications of animal manure and compost may cause an adverse effect on soils and crops. When excess manure is applied, the nitrogen will be accumulated in soil, resulting in accumulation of nitrate in crops and pollution of the groundwater. Guidelines for application rates are recommended, to maintain soil productivity and quality of crops, and to prevent the environmental pollution.

• Journal of the Korean Chemical Society
• /
• v.18 no.1
• /
• pp.31-39
• /
• 1974

Solutions of $Mn^{++}, Co^{++} and Zn^{++}$ were mixed with various dibasic organic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with acid anion concentrations, it was concluded that $Mn^{++}, Co^{++}$ and $Zn^{++}$ formed one-to-one complexes with succinate, malonate, o-phthalate and tartrate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present investigation indicated that the relative stabilities of the complexes increased in the order: $Mn^{++} < Co^{++} < Zn^{++} complexes, Succinate < malonate < o-phthalate < tartrate complexes, Aqueous < mixed solvent systems.$

• The Journal of Engineering Research
• /
• v.7 no.1
• /
• pp.79-87
• /
• 2005

[TEACOOH]-Montmorillonite intercalations complex obtained from Na-Montmorillonite and 10-Carboxy-n-decyldimethylethylammonium bromide(organic cation) was reacted with the monomer($\varepsilon$-caprolactone) to achieve the [TEACOOH]-$\varepsilon$-caprolactone-Montmorillonite intercalations complex. From intercalations complex Montmorillonite/Polycaprolactone Nanocomposite in which montmorillonite(inorganic material) is chemically linked with the polycaprolactone(organic polymer) was formed at $220^{\circ}C$ for 48 h. The basal spacing for the sample obtained after polymerization, extraction with methanol and dried at $65^{\circ}C$ in high vacuum for 24 h was 50.7 $\AA$.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.15 no.1
• /
• pp.15-25
• /
• 2012

Arundinaria munsuensis population were classified into Lespedeza maximowiczii dominant population and Spiraea prunifolia for. simpliciflora dominant population in the habitat of Jiri Mt. In the study sites, soil organic matter, total nitrogen, available phosphorous, exchangeable K, exchangeable Ca, exchangeable Mg contained, cation exchange capacity, and soil pH were ranged from 14.52~16.13%, 0.57~0.59%, 5.57~10.24 (mg/kg), 0.44~0.49 ($cmol^+/kg$), 0.62~0.92 ($cmol^+/kg$), 0.31~0.32 ($cmol^+/kg$), 28.26~32.44 ($cmol^+/kg$) and 4.33~4.48 respectively. DCCA ordination analysis showed that Lespedeza maximowiczii dominant population dwells where pH, exchangeable Ca and exchangeable Mg content are high and Spiraea prunifolia for. simpliciflora dominant population is placed where CEC, total nitrogen and organic matter content are high.

• Macromolecular Research
• /
• v.17 no.11
• /
• pp.894-900
• /
• 2009

This study examined the charge carrier photogeneration and hole transport properties of blends of poly (9-vinylcarbazole) (PVK), $\pi$-conjugated polymer, with different weight proportions (0~29.4 wt%) of (PEA)$VOPO_4{\cdot}H_2O$ (PEA: phenethylammonium cation), a novel organic-inorganic hybrid material, using IR, UV-Vis, and energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), steady state photocurrent (SSPC) measurement, and atomic force microscopy (AFM). The SSPC measurements showed that the photocurrent of PVK was reduced by approximately three orders of magnitude by the incorporation of a small amount (~12.5 wt%) of (PEA) $VOPO_4{\cdot}H_2O$, suggesting that hole transport occurred through the PVK carbazole groups, whereas a reverse trend was observed at high proportions (>12.5 wt%) of (PEA)$VOPO_4{\cdot}H_2O$, suggesting that transport occurred via (PEA)$VOPO_4{\cdot}H_2O$ molecules. The transition to a trap-controlled hopping mechanism was explained by the difference in ionization potential and electron affinity of the two compounds as well as the formation of charge percolation threshold pathways.

• Korean Journal of Environmental Agriculture
• /
• v.42 no.2
• /
• pp.152-158
• /
• 2023

This study was conducted to evaluate the effects on soil chemical properties and plant growth after applying soldier fly compost (SFC). Treatments were as follows. No fertilizer (NF), control, SFC1 (SFC 250 kg/10a), SFC2 (SFC 500 kg/10a) and SFC3 (SFC 1,000 kg/10a). As compared to control in the pot test, organic matter (OM) and exchangeable sodium (Ex-Na) of SFC3 treatment were increased, and growth and nutrient uptake of young radish were not significantly different. Correlation coefficient between soil chemical factors like total nitrogen (T-N), OM, and CEC and uptake of nitrogen (N) and phosphorus (P) was significantly positive (p≤0.05). Compared to control in the field test, electrical conductivity, T-N, OM, Av.-P₂O₅, and CEC was increased, and lettuce growth was not significantly different. Correlation coefficient between application amount of SFC and T-N, OM, and Av.-P₂O₅ was significant positively (p≤0.05). These results indicated that the application of SFC improved nutrient availability of soil by increasing OM and CEC.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2004.08a
• /
• pp.609-611
• /
• 2004

Sodium salt of photoluminescent Eu-containing polyoxometalate (Eu-POM) was newly synthesized and its chemical structure and physical properties characterized. The Eu-POM was unstable outside the pH range 5.5-8.5, and a pH just over 7 gave the best yield. We have investigated the photoluminescent properties of Eu-POM with changing the reactants ratio of heteropolytungstate and $EuCl_3{\cdot}6H_2O}$. The Eu-POM was characterized by UV/Vis, FT-IR, $^1H$-NMR, PL and XPS. Eu-POM emits orange light of 590nm when excited with the light of 280nm. Furthermore, we made dodecyltrimethylammonium (DDTA) salt of Eu-POM (Eu-POM/DDTA) by exchange of the counter cation. The Eu-POM/DDTA is soluble in common organic solvents, while Eu-POM is only soluble in water. And it emits reddish orange light of 625nm when excited with light of 250nm.