• Journal of Veterinary Clinics
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• v.2 no.1
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• pp.105-114
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• 1985

The optimal conditions for the evaluation of serum ornithine carbamyltransferase activity, based on the do-termination of citrulline formed during the enzymatic reaction, were investigated and the serum ornithine carbamyltransferase activity of cattle were surveyed. Barbital-acetate buffer(70m moles/L, pH 7.0 at $37^{\circ}C$) were usea for the entire experiment. The results were as follows. 1. When the concentration of $H_2SO_4$ in color reagent exceeds 3.0 m1/100m1 the serum protein precipitated and absorbance increased. 2. The concentrations of antipyrine and diacetylmonoxime required for maximal color formation were 1g/L and 5g/L, respectively. 3. The absorbance was maximal when the reaction mixture was boiled for 25 minutes. 4. The chromogen were stable for at least 60 minutes under loon lighting condition, but decolorized rapidly under direct sunlight. 5. The minimal concentration of urease solution(Sigma Chemical Co., Type III) required for elimination of serum urea was 0, 6mg/ml. 6. When the concentration of L-ornithine solution increased up to 22m moles/L, the ornithine carbamyltransferase activity was not inhibited by zwitterion of ornithine. 7. In accordance with the increase of carbamylphosphate concentration the ornithine carbamyltransferase activity increased and the nonenzymatic citrulline production also increased slightly. 8. The standard curve of citrulline revealed linear pattern within the range of this experiment (0.1~4.0m moles/L). 9. The ornithine carbamyltransferase activities of normal cattle investigated in this laboratory were 6.85$\pm$4.38U/L (mean$\pm$SD) in cows and 2.89$\pm$2.50U/L in bulls. The range of the activities were 0.39～29.12U/L in cows and 0.06~17.34U/L in bulls.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.803-813
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• 2017

This study discussed the possible optimization of enzyme-mediated calcite precipitation (EMCP) as a soil-improvement technique. Magnesium chloride was added to the injection solution to delay the reaction rate and to improve the homogenous distribution of precipitated minerals within soil sample. Soil specimens were prepared in 1-m PVC cylinders and treated with the obtained solutions composed of urease, urea, calcium, and magnesium chloride, and the mineral distribution within the sand specimens was examined. The effects of the precipitated minerals on the mechanical and hydraulic properties were evaluated by unconfined compressive strength (UCS) and permeability tests, respectively. The addition of magnesium was found to be effective in delaying the reaction rate by more than one hour. The uniform distribution of the precipitated minerals within a 1-m sand column was obtained when 0.1 mol/L and 0.4 mol/L of magnesium and calcium, respectively, were injected. The strength increased gradually as the mineral content was further increased. The permeability test results showed that the hydraulic conductivity was approximately constant in the presence of a 6% mineral mass. Thus, it was revealed that it is possible to control the strength of treated sand by adjusting the amount of precipitated minerals.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.423-434
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• 2020

The effects of amino acid and/or urea liquid fertilizer application on the growth and phytochemicals of Perilla leaves were summarized as follows; The fresh weight of the perilla leaves was in the order of CF, CL, KLF, and control, and 39.7 g, 37.4 g, 36.5 g and 32.3 g were measured. The plant height increased by 71.6 cm in the CF treatment than in the control(54.6 cm). The number of nodes was 14.3 node in CF treatment and 19% more than control(12 node). The vitamin C content tends to be increased by fertilizing the amino acid solution in the perilla leaf. The components of polyvalent unsaturation of n-6 origin were measured in CF treatment, KLF treatment, and control in 10.19 mg, 10.18 mg, and 9.38 mg per 100 g, respectively. Glutamic acid, aspartic acid, leucine, arginine, alanine and lysin were contained in perilla leaf amino acid. Glutaminic acid content was found to be 455.1 mg, 495.6 mg, and 478.8 mg in the control, KLF and CF treatment per 100 g, respectively. Effective nutrition management using amino acid fertilizer optimizes crop yield and profitability, it is important to reduce the negative environmental risks of using fertilizer.

• BMB Reports
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• v.32 no.5
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• pp.486-491
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• 1999

An engineered cDNA from Phanerochaete chrysosporium encoding both the mature and propeptide-sequence regions of lignin peroxidase H2 (Lip H2) was overexpressed in Escherichia coli BL21 (DE3) to evaluate its catalytic characteristics and potential application as a pollution scavenger. All expressed proteins were aggregated in an inactive inclusion body, which might be due to inherent disulfide bonds. Active enzyme was obtained by refolding with glutathione-mediated oxidation in refolding solution containing $Ca^{2+}$, heme, and urea. Propeptide-sequence region was not processed as evidenced by N-terminal sequence analysis. Recombinant Lip H2 (rLip H2) had the same physical properties of the native protein but differed in the $K_{cat}$. Catalytic efficiency ($k_{cat}/K_m$) of rLip H2 was slightly higher than that of the native enzyme. In order to express an active protein, fusion systems with thioredoxin or Dsb A, which have disulfide isomerase activity, were used. The fused proteins expressed by the Dsb A fusion vector were aggregated, whereas half of the thioredoxin fusion proteins were recovered as a soluble form but still catalytically inactive. These results suggest that Lip H2 may not be expressed as an active enzyme in Escherichia coli although the activity can be recovered by in vitro refolding.

• Journal of Pharmaceutical Investigation
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• v.15 no.2
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• pp.73-82
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• 1985

Each parching Anemarrhenae Rhizoma with 25% ethanol and normal saline has been used for anti-inflammatory, expectorant, antipyretic, sedative and diuretic, and so on. In order to investigate the differences of referential efficacy about each fractionated part of the aqueous extracts, pharmacological studies were carried out. The results of studies were summerized as follows : 1. By the administration of 25% ethanol treated preparation (F-I-1), the increase in urinary volume and $Na^+$ extraction was significantly recognized. 2. The excretion of electrolyte $Na^+$ by saline solution treated preparation (F-II-1) was significantly recognised in normal rats. 3. The increase of urinary volume and urinary $Na^+$ and $Cl^-$ excretion by F-I-1 and n-butanol insoluble parts of F-I-1 (F-I-3) was significantly recognized in $HgCl_2-induced$ acute renal failure of rats. 4. The increase of plasma $Na^+$ by F-I-1 and urea nitrogen by F-I-1 and F-I-3 in acute renal failure of rats was significantly recognized. 5. The increase of urinary volume by F-I-1 and F-I-3 was recognised in mice.

• Journal of Powder Materials
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• v.12 no.6 s.53
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• pp.413-421
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• 2005

Copper is able to work as a current collector under wide range of hydrocarbon fuels without coking in Solid oxide fuel cells (SOFCs). The application of copper in SOFC is limited due to its low melting point, which result in coarsening the copper particle. This work focuses on the sintering of copper powder with ceria coating layer. Ceria-coated powder was prepared by thermal decomposition of urea in $Ce(NO_3)_3\cdot6H_2O$ solution, which containing CuO core particles. The ceria-coated powder was characterized by XRD, ICP, and SEM. The thermal stability of the ceria-coated copper in fuel atmosphere $(H_2)$ was observed by SEM. It was found that the ceria coating layer could effectively hinder the grain growth of the copper particles.

• Journal of the Korean Ceramic Society
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• v.28 no.4
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• pp.338-346
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• 1991

The alumina-titania composite powders coated with Al2O3 were prepared by the method of hydrolysis-deposition of mixed aluminium salt solution of Al2(SO)4-Al(NO3)3-Urea. The effects of coating-process parameters on the characteristics of coated composite powders were also investigated. As the content of TiO2 dispersed in deionized water increased, the coated composite powders were found to be more uniform in size and unagglomerated. When TiO2 powders were coated for 30 min, the optimum TiO2 content in the coating process was 400 mg/ι. The size of TiO2 particle was increased approximately from 0.7${\mu}{\textrm}{m}$ to 1.0${\mu}{\textrm}{m}$ through coating of Al2O3. The IEP of coated composite powders was pH=8.3 identical to the value of aluminium hydroxides and the zeta-potential showed nearly similar values each other. When heat treating coated composite powders at 130$0^{\circ}C$, only two phases of TiO2(rutile) and Al2TiO5 were observed. These results showed that the suface of TiO2 could be uniformly coated with the aluminium hydroxide.

• Journal of Korean Society on Water Environment
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• v.31 no.1
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• pp.42-48
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• 2015

This study focused on effective decomposition methods for low concentrated organic compounds from the reuse of industrial wastewater, and confirmed the possibility through photocatalyst media. Photocatalyst immobilized media was developed to carry on this experiment which confirmed the removal possibility of low concentrated organic compounds. Considering the stability and efficiency of photocatalyst immobilization, inorganic support, hollow bead, and $TiO_2$ nano powder were used. As a result of the removal experiment, the removal efficiencies of acetonitrile, ethanol, IPA(Isopropyl alcohol), methanol were above 75% after 15 minutes while those of acetone, acetaldehyde, urea were 10%, 45%, 20%, respectively after 60 minutes. If further studies were made to increase the surface area of the photocatalyst immobilized media, the efficiency of the removal of low concentrated organic compounds can be improved and this solution can also be used in an actual treatment process.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.262-267
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• 2006

Increased application of glyphosate (Gly) in glyphosate-resistant (GR) soybean cropping systems may affect rhizospheric microorganisms including IAA-producing rhizobacteria (IPR) and their effect on the growth of soybean. This field experiment was conducted to assess IPR populations in the rhizosphere of GR soybean ('Roundup-Ready' DeKalb DKB38-52) treated with glyphosate and foliar amendment treatments such as $PT21^{(R)}$ (urea solution with N 21 %) and $Grozyme^{(R)}$ (Biostimulant: mixtures of micro nutrients and enzymes). Effects of herbicide, sampling date, and their interaction on total bacterial numbers were significant (P < 0.001, 0.001, 0.013, respectively). Total bacteria (TB) numbers were increased with glyphosate treatment at 20 d after application and highest TB populations were associated with $Grozyme^{(R)}$ application, possibly due to the additional substrate from this product. The IPR of the soybean rhizosphere was significantly affected by herbicide, sampling date, and the herbicide*foliar amendment interaction. The ratios of numbers of IPR to TB ranged from 0.79 to 0.99 across the sampling dates irrespective of treatments. IPR numbers were slightly hindered by glyphosate application regardless of foliar amendment.

• Textile Coloration and Finishing
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• v.21 no.4
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• pp.39-45
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• 2009

PVA films were crosslinked with dimethylol dihydroxy ethylene urea (DMDHEU) and three polycarboxylic acids of butanetetracarboxylic acid (BTCA), citric acid and malic acid Different factors influencing the crosslinking treatment with BTCA were investigated including BTCA and sodium hypophosphite (SHP) concentration, curing temperature and time. The cured films was extracted with boiling water and gel fraction was calculated based on weight change of the PVA films. The gel fraction of PVA films increased with increasing curing temperature and time. And the resistance to water and thermal stability of the crosslinked PVA films improved with the BTCA crosslinking treatment. While crosslinking with citric acid gave the highest gel fraction among the crosslinkers, crosslinking with malic acid showed the highest absorbancy in 0.9% saline solution, which was attributed to lower crosslink density and high number-average molecular weight between crosslinks. The superabsorbent PVA films could be prepared by adjusting the crosslinking condition of PVA with polycarboxilic acids.