• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.61-65
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• 2010

Phytoextraction is a method of phytoremediation using plants to remediate metal-contaminated soils. Recently, various chelating agents were used in this method to increase the bioavailability of metals in soils. Even though phytoextraction is an economic and environment-friendly method, this cannot be applied in highly metal-contaminated areas because plants will not normally grow in such conditions. This research focuses on identifying chelating agents which are biodegradable and applicable to highly metal-contaminated areas. Lead (Pb) as a target metal and cysteine (Cys), histidine (His), citrate, malate, oxalate, succinate, and ethylenediamine (EDA) as biodegradable chelating agents were selected. Ethylenediamine tetraacetic acid (EDTA) was used as a comparative standard. Plants were grown on agar media containing various chelating agents with Pb to analyze the effect on root growth. Cys strongly increased the inhibitory effect of Pb on root growth of plants, while, His did not affect on it significantly. The inhibitory effect of oxalate is weak, and malate, citrate, and succinate did not show significant effects. Both EDTA and EDA diminished the inhibitory effect of Pb on root growth. The effect of EDA is correlated with decreased Pb uptake into the plants. In conclusion, as biodegradable chelating agents, EDA is a good candidate for highly Pb-contaminated area.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.115-119
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• 2007

Objectives : A morphological classification among Sophora tonkinensis, Menispermum dauricum and Indigofera kirilowii was made through microscopic observation. Method : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by olymphus-BHT. Result : 1. The cross-sections of Sophora tonkinensis and Indigofera kirilowii have piths, but Menispermum dauricum does not have any. 2. The lateral parts of Sophora tonkinensis cortex include the square crystal of calcium oxalate, but Indigofera kirilowii does not. Conclusion : The number of piths and the presence of the square crystal of calcium oxalate can be used to distinguished Sophora tonkinensis from Indigofera kirilowii.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.33-36
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• 1991

For its outstanding magnetic property, preparations of MnZn ferrite were studied with various method. In this study, MnZn ferrite powders were prepared from ammonium oxalate and mixed metal sulfate by the controlled coprecipitation process. Considering to low dissolved each metal ion, high production yield and particle size, the established optimum reaction conditon by the statistical analysis of each results are that reaction temperature is $25^{\circ}C$, concentration of metal sulfate is 0.3M, molar ratio of ammonium oxalate/metal sulfate is 1.1:1. The effective experimental factor and characterization of the precipitated powder at optimum condition were studied.

• Analytical Science and Technology
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• v.8 no.4
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• pp.855-858
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• 1995

Vegetables contain more or less calcium. By the traditional method the total calcium in the vegetable was analyzed. A part or calcium in the vegetable is fixed as calcium oxalate and the calcium does not utilize for nutrition. In this investigation the free calcium was determined by extraction in boiling water, the combined calcium with oxalic acid was determined by extraction in 0.1 M hydrochloric aci and the other calcium combined with protein, amino acid etc. was estimated. The amount of calcium obtained from the difference between the total calcium and calcium exmtaining in calcium oxalate was estimated to be nutritious.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.239-244
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• 2000

Synthesis and high temperature phase stability of $_{1+x}$ Co$_{y}$ Mn$_{2-y}$ $O_4$(0$\leq$x$\leq$0.2,y=0,1/9,1/6) spinel, both the excess lithium and cobalt added, have been studied. The spinel was prepared by oxalate precipitation method as the wet chemical process. Oxalate derived spinel was synthesized by heating of precipitates at temperature lower than $600^{\circ}C$. As a result of the TG-DTA and XRD analysis of prepared and quenched powders, it was found that reversible phase transitions started at temperatures $T_1$, $T_2$및 $T_{2'}$. The transitions involved weight (oxygen) loss and gain during heating and cooling. The effects of Li excess and Co doping on the spinel lattice constant, phase stability and transition temperatures of the prepared powders are investigated. This study would provide important data for determining the spinel preparation process such as synthesis temperature and cooling speed.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.2
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• pp.63-71
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• 1995

Defatted sesame flour is the by-products obtained after oil extracting process. Although this flour has high quality and quantity of protein its use is limited only for animal feed and fertilization. Sesame seeds contain antinutrients such as oxalate, phytate and phenol compounds and these compounds lower their nutritive value. recently, ultrafiltration(UF) has been used to concentrate protein from various food sources. This study was carried out to examine the effects of UF with different membrane pore size on the components of sesame protein concentrates including antinutrients and to compare with that of conventional acid-precipitated sesame protein isolate. The protein contents of sesame protein concentrates prepared by JF using 10K, 30K, 100K were 84.2%, 82.7%, 76.4% and the protein yields were 36.44%, 34.69, 31.43% and the protein contents was 88.7% Alkali extraction process at pH 9.0 followed by UF technique reduced oxalate and phytate content. There were 85% and 94% reduction of oxalate and phytate content by UF with membrane pore size of 100K daltons, respectively. However, the content of total phenol compounds was not reduced by this method. About 99% of calcium and 50% of zinc were removed by UF with membrane of 100K daltons. total essential amino acid contents of sesame protein concentrates prepared by UF were decreased slightly when compared with acid-precipitated sesame protein concentrate.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6257-6260
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• 2013

Gallstone disease is a major surgical problem in many populations; it is probably related to diet, especially excessive consumption of meat. The objective of this study was to determine the chemical composition of gallstones and their association with neoplastic changes including cholangiocarcinomas in cholecystectomised patients. The chemical composition of gallstones from 40 patients (8 males and 32 females) was analyzed. This is a prospective study performed in Baquba teaching hospital in the period from 1/10/2012 to 1/1/2013 in which we collected the gallstones for the patients who underwent cholecystectomy, whether open or laparoscopic. The stones were classified according to their chemical composition as a mixed stones (MS), and examined using a stone analysis set (chemical qualitative method) for calcium, magnesium, phosphate, uric acid and oxalate which was used reagent for qualitative determination of main individual components of stones. The results of this study showed the highest incidence of gallstones in the age group 40-49 was 13 cases followed by 11, 8 and 4 cases for age groups 30-39, 50-59, 20-29 and 60 and above, respectively. The chemical analysis showed the majority of gallstones were mixed, 38 containing calcium followed by 37 cases with uric acid, 28 with magnesium, and 25 and 22 stones with oxalate and phosphate, respectively. Microscopically, we confirmed neoplastic changes (17.5%) as cholangiocarcinomas (CCCs) (7.55%) and dysplastic cells of carcinoma in situ in 4 (10%), 31 (77.5%) cases were chronic cholecystitis and 2 (5%) cases were acute cholecystitis with empyema out of bile duct disorders patients. In conclusion, majority of cases had mixed gallstones that involved five and four of inorganic chemicals of calcium, magnesium and phosphate, the highest incidence of gallstones in age group 40-49 years old was 13 cases, and neoplastic changes were confirmed (17.5%) including CCCs, (7.5%) and dysplastic cells of carcinoma in situ (10%), while 31 (77.5%) cases were chronic cholecystitis.

• The Korea Journal of Herbology
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• v.20 no.2
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• pp.77-82
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• 2005

Objectives : A morphological classification among Achyranthes japonica Nakai (produced in Korea), A. bidentata Blume (imported from China), and Cyathula officinalis Kuan (used in China exclusively) was made through microscopic observation. Method : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by olymphus-BHT. Result : 1. Korean A. japonica Nakai has slim roots, whose diameter is $1{\sim}5\;mm$. 1) Most of its intersection is stele, which includes a lot of vascular bundles. The inside of vascular bundles shows the arrangement of $2{\sim}4$ cycles, the innermost wheel of which is divided into two parts. 2) Parts of parenchymatous cell include Crystal sand of calcium oxalate. 2. The diameter of the roots of Chinese A. bidentata Blume is $0.4{\sim}1\;cm$. 1) The xylem in the vascular bundle in the middle of its intersection is rather big, around which the inner parts of the vascular bundles are arranged in the shape of $2{\sim}4$ cycles around. The most outside part of it is small, and the middle part is gathered into $2{\sim}3$ groups. 2) Parts of parenchymatous cells include Crystal sand of calcium oxalate. 3. The roots of Chinese C. officinalis Kuan is thick, whose diameter is $0.5{\sim}3\;cm$. 1) Vascular bundle of its intersection is spotted, arranged in the shape of $4{\sim}11$ concentric circles, whose center is divided into $2{\sim}9$ groups. 2) Parenchymatous cells include crystal sand and square crystal of calcium oxalate. Conclusion : It is concluded that Achyranthes japonica Nakai, A. bidentata Blume, and C. officinalis Kuan have different shapes in both external forms and internal intersections, so that they can be easily distinguished from one another through microscopic observation.

• Journal of Life Science
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• v.20 no.7
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• pp.1041-1046
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• 2010

Phytoextraction is a technique which uses plants to clean up metal-contaminated soils. Recently, various chelating agents were introduced into this technique to increase the bioavailability of metals in soils. Even though the technique is an economic and environment-friendly method, this cannot be applied in highly metal-contaminated areas because plants will not normally grow in such conditions. Therefore, this research focuses on identifying chelating agents which are biodegradable and applicable to highly metal-contaminated areas. Alunimum (Al) as a target metal and cysteine (Cys), histidine (His), citrate, malate, oxalate, succinate, and ethylenediamine (EDA) as biodegradable chelating agents were selected. Ethylenediamine tetraacetic acid (EDTA) was used as a comparative standard. Plants were grown on agar media containing various chelating agents with Al to analyze the effect on plant growth. His slightly diminished the inhibitory effect of Al on root growth of plants, whereas, Cys, citrate, malate, oxalate, and succinate did not show significant effects. Both EDTA and EDA strongly diminished the inhibitory effect of Al on root growth. The effect of EDA is correlated with decreased Al uptake into the plants. In conclusion, as a biodegradable chelating agent, EDA is a good candidate for highly Al-contaminated areas.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.288-294
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• 2007

The LSCF cathode far Solid Oxide Fuel Cell was investigated to develop high performance unit cell at intermediate temperature by modified oxalate method with different electrolytes and different pH. The LSCF powders employed La, Sr, Co and Fe oxides, oxalic acid, ethanol and $NH_4OH$ solution were synthesized with pH controlled as 2, 6, 7, 8, 9 and 10 at $80^{\circ}C$ Single crystalline phase was obtained from pH $2{\sim}9$. on the other hand, $La_2O_3$ appeared from pH 10. Very fine powder with particle size of 50 nm was obtained at calcination temperature of $800^{\circ}C$ for 4 hours. LSCF cathode synthesized at pH 7 showed the highest electric conductivity in the temperature range of $600^{\circ}C$ to $900^{\circ}C$ its value was 950 S/cm at $900^{\circ}C$ Under same synthesis conditions, polarization resistance of each LSCF cathode was changed with different calcination temperatures. As-prepared powder presented 2.52, 1.54 and $2.58\;{\Omega}$ at $600^{\circ}C$ with ScSZ, 8Y-YSZ and GDC as its electrolyte respectively after calcination at $800^{\circ}C$ for 4 hours.