• Korean journal of applied entomology
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• v.10 no.2
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• pp.77-83
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• 1971

In order to find out the decomposing factors of Sumithion in mineral diluents, the physical and chemical properties of the diluents such as talcs, bentonites, diatomaceous earth and other clay minerals was studied in relation to the decomposition rate of Sumithion in dust formulations. The total base, moisture adsorption capacity, pH, specific surface, water contents, active $Fe^{++}$, ignition loss and cation exchange capacity were analysed as the properties of mineral diluents, and these properties were correlated with the stability of Sumithion in dust formulations. And in hope of finding out the main factors among those properties of diluents, the decomposed products of Sumithion in dust formulations prepared with standard Sumithion were separated by the methods of column chromatography and investigated by thin layer chromatography. The following results were otbained; 1. The total base, moisture adsorption capacity, specific surface, water contents, active $Fe^{++}$ and cation exchange capacity of mineral diluents were found to be highly effective on the rate of decomposition of Sumithion in dust formulations. 2. Decomposed products of Sumithion in dust formulations were found to be dimethylphosphorothionate, 3-methyl-4-nitro phenol and its derivatives. And one fraction was not dissolved in n-hexane and ethylether, but was soluble in methylalcohol and ethylalcohol. 3. The moat highly correlated properties of diluents with the decomposition rate of Sumithion in dust were found to be the total base and water contents. 4. In regard to the kind of diluents, it was found that the rate of decomposition of Sumithion in dust formulations was higher in order of bentonite, diatomaceous earth, kaolin and talc.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.193-199
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• 2017

In this study, changes of soil properties including soil texture, specific surface area, organic matter content, pH, cation exchange capacity and exchangeable cations content were investigated in response to strong acid or base accident. The properties changed significantly when the soil reacted with 10 M HCl or 1 M NaOH (i.e., when one gram of soil received 50 and 5 mmol of HCl or NaOH), respectively. When the soil reacted with 10 M HCl or 1 M NaOH solution, soil texture changed from sandy loam to loamy sand and specific surface areas decreased from $5.84m^2/g$ to 4.85 and $1.92m^2/g$, respectively. The soil organic matter content was reduced from 3.23% to 0.96 and 0.44%, and the soil pH changed from 5.05 to 2.35 and 10.65, respectively. The cation exchange capacity decreased from 10.27 cmol/kg to 4.52 and 5.60 cmol/kg, respectively. Especially, high concentrations of $Al^{3+}$ or $Na^+$ were observed in acidic or basic spills, respectively, which is likely to cause toxicity to terrestrial organisms. The results suggest that restoration of soil properties, as well as soil remediation, needs to be carried out to maintain the soil function in chemical spill sites.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.407-413
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• 1998

The influence of the anion composition of simulated acid rain on cation leaching of two soils with different surface charge properties was examined. Four mixtures of mole ratio of $SO_4:NO_3$(1:0, 2:1, 1:1, 0:1) with pH 2.0 simulated acid rain were applied to an Inceptisols(Gyuam series) and Andisols(Pyeongdae series). The Andisols had higher $SO_4{^{2-}}$ adsorption capacity than the Inceptisols because of its higher point of zero charge(PZC, pH 6.5) than Inceptisols(PZC pH 3.1). Cation leaching in Andisols varied directly with the $NO_3$ content of the leaching input due to higher mobility of $NO_3$ compared with $SO_4$ that was absorbed. The pH of the Andisols was higher with the addition of $Na_2SO_4$ than the addition of $NaNO_3$ indicating that this soil behaves as a base and has a high $SO_4$ adsorption capacity. The relative $NO_3{^-}/SO_4{^{2-}}$ content input had no effect on cation leaching of the Inceptisols. Amounts of leaching on the Andisols by simulated acid rain were higher than Inceptisols. This experiment explained that anion composition of acid rain plays a significant role in the cation leaching of soils which are able to adsorb $SO_4$.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.94-98
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• 2008

A fundamental study was developed concerning the novel solvent extraction of the tetravalent metal ions; zirconium(IV), hafnium(IV) and thorium(IV). Their extraction behavior in toluene was investigated with a recently synthesized naphthol-derivative Schiff base, 1-({[4-(4-{[(E)-1-(2-hydroxy-1-naphthyl)methyliden]amino}phenoxy) phenyl]imino}methyl)-2-naphthol (HAPMN). The spectrophotometrical examination of the complex formation between HAPMN and the Zr(IV), Hf(IV) and Th(IV) ions in acetonitrile revealed the formation of stable 1:1 complexes in the solution. After the thorium extraction in toluene, it was found that [Th(OH)3HA] was the respective deriving substance. While, in the case of zirconium and hafnium extraction, the extracted adduct was found to be [M4(OH)8(H2O)16Cl62HA]. The stoichiometric coefficients of these extracted species were determined by the slope analysis method. The extraction reaction followed a cation exchange mechanism.

• Advances in nano research
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• v.2 no.2
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• pp.89-98
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• 2014

A novel and simple method for the synthesis of nano-magnetite particles is disclosed. In the novel procedure, $Fe^{2+}$ is the only source of metal cation. Carboxymethylcellulose (CMC) is used as the structure directing agent. The phase analysis of the nano-particles was performed using XRD and electron diffraction techniques. Size and morphology analysis was performed using light scattering and TEM techniques. The effect of $NH_4OH$ solution (32 wt. %) at different CMC concentrations on the size distribution of the final magnetite powders is studied. An optimal base concentration exists for each CMC concentration leading to minimal agglomeration. There exists a minimum CMC concentration (0.0016 wt. %), lower than that no magnetite forms. It is shown that using the new method, it is possible to immobilize a lipase enzyme (Candida Rugosa) with immobilization efficiency larger than 98 % with a loading more than 3 times the reported value in the literature. The latter phenomenon is explained based on the agglomerate state of the nano-particles in the liquid phase.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.890-896
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• 2004

This study is intended as an investigation of the EK remediation characteristics of natural soil with treatment time under unsaturated conditions. EK tests are performed under the voltage gradient of 1V/cm, the degree of saturation of 82.8%, and the installing of cation exchange membrane. It was found from the results that the acid front is initially transported at 0.75cm/day and then continuously degreased until the transport velocity of the acid front is balanced to the velocity of the base front. The residual lead concentration indicated the maximum value at the treatment time of lOdays, then the increasing of treatment time largely decreases the concentration within the sample though electromigration than electroosmosis.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.1
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• pp.7-16
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• 1989

To determine the effect of sodium plus potassium to chloride ratio and lysine level on blood pH, blood acid-base parameters, lysine-arginine antagonism and growth performance, four hundred and thirty two chicks of 3 days age were used in a completely randomized $3{\times}3$ factorial experiment. Variables contained three levels of lysine (0.8, 1.2 and 1.6%) and dietary electrolyte (100, 200 and 300 mEq/kg). Birds fed 200 mEq/kg and electrolyte had the best growth rate and feed efficiency, followed by those fed 300 mEq/kg and 100 mEq/kg electrolyte. It is proposed that high levels of dietary electrolyte may improve the growth of chicks fed diets containing excess lysine by increasing lysine catabolism. High or low levels of lysine and dietary electrolyte resulted in higher mortality than those of optimum level (1.2%) of lysine and 200 mEq/kg of electrolyte balance. When the electrolyte level was increased, the pH, $pCO_2$, base excess, $HCO_3{^-}$ and total $CO_2$ of blood plasma were increased. The utilization of nutrients was changed when the electrolyte and lysine were manipulated. Plasma chloride tended to be greater in chicks receiving high chloride diet and was the highest in chicks fed the high lysine diet. Plasma sodium and potassium were unaffected by dietary lysine. Diet containing high lysine decreased the level of arginine and excess dietary electrolyte increased arginine level in plasma. It may be concluded that cation supplementation tended to alleviate the lysine-arginine antagonism but chloride exacerbated. Tibia bone length and ash contents were significantly affected by electrolyte balance and lysine level.

• Korean Journal of Organic Agriculture
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• v.17 no.4
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• pp.567-575
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• 2009

Organic pear (Pyrus pyriforia) fruits have remarkably increased in Korea since year 2000 due to increase consumer's demand for the fruit, and the farmers are keep trying to change their cultivation system that is replaced from conventional farming to organic-base farming for the fruit. However, there is little information for the soil properties, tree nutrition, and tree growth at organic orchards in Korea. Therefore, this study was established to investigate for the chemical properties of soils and leaf and bud characteristics of a conventional and organic pear trees in experimental orchards for two years. Commercial (Sanwool, YoungHwa Co., Korea) compost was applied to the orchard soils with conventional farming systems for two years for pear trees (10 to 15 year old trees) in KyungSan, Korea. The compost application increased pH, organic matter content, cation exchange capacity (CEC), and, microbial biomass in the soil. The compost treatment also increased specific leaf weight and foliar $P_2O_5$ concentration as well as leaf and floral bud sizes.

• Electrical & Electronic Materials
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• v.11 no.11
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• pp.9-17
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• 1998

The dependence of the ionic conductivity on the B-site ion substitution in (Li0.5La0.5)Ti1-xMxO3 (M=Sn, Zr, Mn, Ge) system has been studied. Same valence state and various electronic configuration and ionic radius of Sn4+, Zr4+, Mn4+ and Ge4+(4d10(0.69$\AA$), 4p6(0.72$\AA$), 3d10(0.54$\AA$) and 3d3(0.54$\AA$), respectively) induced the various crystallographic variaton with substitutions. So it was possibleto investigate the crystallographic factor which influence the ionic conduction by observing the dependence of the conductivity on the crystallographic factor which influence the ionic conduction by observing the dependence of the conductivity on the crystallographic variations. We found that the conductivity increased with decreasing the radii of B-site ions or vice versa and octahedron distortion disturb the ion conduction. The reason for this reciprocal proportion of conductivity on the radius of B-site ions has been examined on the base of the interatomic bond strength change due to the cation substitutions. The results were good in agreement with the experimental results. Therefore it could be concluded that the interatomic bond strength change due to the cation substitutions may be the one of major factors influencing the lithium ion conductivity in perovskite(Li0.5La0.5) TiO3system.

• The Korean Journal of Ecology
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• v.28 no.6
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• pp.417-431
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• 2005

Soils of Korea experienced with long-term acidic deposition have been exhaustively leached exchangeable base cation (BC) for plant nutrient comparable with soils of forest decline areas in Europe and N. America. Ratios of $BC/Al^{3+}$ of most soils are below than 1, which value is critical load for plant growth. Acid soil applied with dolomitic liming is increased as much as 20% and 244% in concentrations of $Ca^{2+}$ and $Mg^{2+}$, respectively, as well as shrub leaves increase much cation uptake by 1 year later. Ions of $NO_3^-$ and $NH_4^+$ in acid rain are absorbed by the canopy acted as the sink but f is leached out from the canopy to throughfall as the source at Gwangneung forest with a little of acidic deposition, however, such sink and source functions are not found at Kwanaksan forest because of so much deposition. In coniferous and deciduous forested watershed ecosystems ions of $K^+$, $Cl^-$, $NO_3^-$ and $SO_4^{2-}$ from throughfall are retained in forest floor but ions of $Na^+, $Mg^{2+}$ and $Ca^{2+}$ are leached from the floor to streamwater.