• Journal of Veterinary Clinics
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• 제7권2호
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• pp.501-509
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• 1990

This study was designed to examine effects of $\alpha$$_2$-Adrenergic Antagonists on blood chemical values in xylazine-sedated dogs. Twenty-four crossbred dogs of both sexes were intramusculary injected with a standard dosage of xylazine(2.2mg/kg of body weight). Righting reflex was uniformly lost and considered to be the point of maximum sedation. When the dogs were maximally sedated, tested groups were in-travenously injected with yohimbine 0.125mg/kg, 4-aminopyridine(4-AP) 0.3mg/kg, and a combination of yohimbine with 4-AP. Control group was intravenously 1 $m\ell$ of physiological saline solution. Total protein(T.P), albumin, glucose, aspartate aminotransferase(AST), alanine aminotrnasferase(ALT), blood urea nitrogen(BUN) were analyzed in the conditions of 0-, 30-, 60- and 120-minute after the administration of drugs. The results obtained in the study were as follows. 1. Changes of T.P, albumin, AST, ALT and BUN values in the control group were not significant during or after xylazine administration for at least 120minutes. 2. No changes of T.P, albumin, AST, ALT and BUN values in the tested groups were observed during or after $\alpha$$_2$-Adrenergic Antagonists treatment. 3. Serum glucose values of control group were getting remarkably increased after xylazine injection. 4. The xylasine-induced hyperglycemia was reversed in the dogs administrated with $\alpha$$_2$-Adrenergic Antagonists. Therefore, the results of the study show that the combined treatment with antagonists may be useful for accidental overdoses of xylazine and rapid reversal of animals sedated with xylazine.

• Transactions of the Korean Society of Automotive Engineers
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• 제22권4호
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• pp.152-159
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• 2014

Urea solution as a reductant of SCR has been widely used to reduce NOx emissions from diesel engine. But it has lots of problems which are freezing at low temperature due to liquid state, deposition of solid formation in the exhaust, dosing device, and complex package such as mixers for uniform concentration of ammonia. In order to overcome these obstacle, ammonium carbonate which is one of solid ammonium materials to produce ammonia gas directly by sublimation process is considered. Simple reactor with visible widow was designed to predict equilibrium temperature and pressure of ammonium carbonate. To simulate real operation conditions under automobile environment, several cycles of heating and cooling condition were settled, two different re-solidification materials were extracted from the reactor and visible window. Analytical study is performed to characterize these unknown materials by XRD(X-Ray Diffraction), FT-IR(Fourier Transform Infrared Spectroscopy), and EA(Elemental Analyzer). From analytical results, re-solidification materials from heating and cooling cycles are very similar to original material of ammonium carbonate.

• Journal of Pharmacopuncture
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• 제17권3호
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• pp.7-15
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• 2014

Objectives: The present study investigated the toxic properties of petroleum ether extract of Wattakaka (W.) volubilis in Wistar female rats. Methods: An in vitro brine shrimp lethality bioassay was studied in A. Salina nauplii, and the lethality concentrations were assessed for petroleum ether extract of W. volubilis. A water soluble portion of the test extract was used in different concentrations from $100-1000{\mu}g/mL$ of 1 mg/mL stock solution. A 24-hours incubation with a 1-mL aliquot in 50 mL of aerated sea water was considered to calculate the percentage rate of dead nauplii with test extract administration against a potassium-dichromate positive control. The acute and the sub-acute toxicities of petroleum ether extract of W. volubilis were evaluated orally by using gavage in female Wistar rats. Food and water intake, body weight, general behavioral changes and mortality of animals were noted. Toxicity or death was evaluated following the administration of petroleum ether extract for 28 consecutive days in the female rats. Serum biochemical parameters, such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, total cholesterol, triglyceride, total protein, glucose, urea, creatinine, sodium, potassium and ${\alpha}$-amylase levels, were measured in the toxicity evaluations. Pathological changes in isolated organs, such as the liver, kidneys, and pancreas, were also examined using hematoxylin and eosin dye fixation after the end of the test extract's administration. Results: The results of the brine-shrimp assay indicate that the evaluated concentrations of petroleum ether extract of W. volubilis were found to be non-toxic. In the acute and the sub-acute toxicity evaluations, no significant differences were observed between the control animals and the animals treated with extract of W. volubilis. No abnormal histological changes were observed in any of the animal groups treated with petroleum ether extract of W. volubilis. Conclusion: These results suggest that petroleum ether extract of W. volubilis has a non-toxic effect in Wistar female rats.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1177-1181
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• 2004

The determination of uric acid in urine samples was studied by a chemiluminescence measurement using tris (2,2'-bipyridine)ruthenium(II)-octylphenylpolyglycolether [Ru$(bpy)_3^{2+}$ -OPE] system. The oxidized uric acid by Ce(IV) excited Ru$(bpy)_3^{2+}$ to emit a chemiluminescence in this system so that the intensity was stoichio-metrically dependent upon the concentration of uric acid. In a reaction cell, a luminescent reagent, oxidant, surfactant and sulfuric acid were flowed into and mixed with a taken sample. Experimental conditions were optimized to obtain the maximum intensity of chemiluminescence. Each reactant solution of more than the following concentration gave a good result: $2\;{\times}\;10^{?4}$ M Ru$(bpy)_3^{2+}$ , 0.01 M Ce(IV), 6% OPE, and 0.33 M $H_2SO_4$. Any interferences were not shown in this process by the investigation of concomitant constitutes such as albumin, creatine, lactic acid, glucose, urea, $Cl^?,\; Mg^{2+},\;Ca^{2+}$ and so on. The linearity of a calibration curve was good with r = 0.998, the relative standard deviation of the slope was 3.3% and the detection limit was 5.6ng/mL. The recoveries of 80 to 91% were obtained from the standard spiked samples. The values were little bit low, but this procedure could be considered to be reliable for the determination of trace uric acid in urine samples.

• Journal of the Korean Institute of Gas
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• 제15권2호
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• pp.21-26
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• 2011

Emissoin of heavy duty vehicle have much positioned in air pollution although its limited number of vehicles. CNG vehicles are coming to the fore as one of the solution of diesel vehicles. CNG vehicles exhaust smaller emission than diesel vehicles on PM and NOx. In this study, aftertreatment technologies are introduced on vehicles which use CNG and hydrogenmixed fuel. Withmixing hydrogen with CNG, combustion efficiency is enhanced, and harmful emission might be decreased, but methane that is main component of CNG brings green house effect. In order to remove methane and NOx in exhaust gas of CNG engine, methane oxidation catalyst and SCR technologies were respectively analyzed.

• Proceedings of the KSME Conference
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2874-2879
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• 2008

The Selective catalytic reduction(SCR) system is a highly-effective device of $NO_x$ reduction for diesel engines. Generally, the ammonia($NH_3$) generated from a liquid urea-water solution is used for the reductant. The ideal ratio of $NH_3$ molecules to $NO_x$ molecules is 1:1 based on $NH_3$ consumption and having $NH_3$ available for reaction of all of the exhaust $NO_x$. However, under the too low and too high temperature condition, the $NO_x$ reduction efficiency becomes lower, due to temperature window. And space velocity also affects to $NO_x$ conversion efficiency. This paper reviews a laboratory study to evaluate the effects of $NO_x$ and $NH_3$ concentrations, gas temperature and space velocity on the $NO_x$ conversion efficiency of the SCR system. The maximum conversion efficiency of $NO_x$ was indicated when the $NH_3$ to $NO_x$ ratio was 1.2 and the space velocity was $60,000\;h^{-1}$. The results of this paper contribute to improve overall $NO_x$ reduction efficiency and $NH_3$ slip.

• KSBB Journal
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• 제16권2호
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• pp.146-152
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• 2001

To avoid the intrinsic problem of aggregation associated with the traditional solution-phase refolding process, we propose a solid-phase refolding method integrated with expanded bed adsorption chromatography. The model protein used was a fusion protein of recombinant human growth hormone and a glutathione S transferase fragment. It was demonstrated that the EBA-mediated refolding technique could simultaneously remove cellular debris and directly renature the fusion protein inclusion bodies in the cell homogenate with much higher yields and less agregation. To demonstrate the applicability of the method, we successfully tested the three representative types of starting materials, i. e., rhGH monomer, washed inclusion bodies, and the E. coli homogenate. This direct and simplified refolding process could also reduce the number of renaturation steps required and allow refolding at a higher concentration, at approximately 2 mg fusion protein per ml of resin. To the best of our knowledge, it is the first approach that has combined the solid-phase refolding method with expanded bed chromatography.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제22권1호
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• pp.20-25
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• 1977

In order to find out the effect of five kinds of cultural treatments in fall crop production of potatoes the experiments were carried out with Simabara cultivar at Chonan in 1976. Sprouting of dormant seed pieces were induced by soaking in 2ppm GA and 250ppm Ethrel mixed solution for 60 minutes. Seed pieces with longer sprouts at transplanting, and increasing of urea(nitrogen) application from 10 to 30 Kg per 10a resulted better growth, yields, and quality. Application of total nitrogen at one time on 24th July(transplanting date) resulted lower emergence, yields, growth, and quality as compared with divided application on 24th July and 15th August and 5th September. Higher transplanting than 60$\times$20cm or 70$\times$17cm resulted slender growth and lower yields. Deeper mulch with wheat straw (from 4 to 12cm) induced lower maximal earth temperature in summer and higher minimal earth temperature in autumn.

• Current Applied Physics
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• 제18권11호
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• pp.1458-1464
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• 2018

An improved method for the preparation of g-$C_3N_4$ is described. Currently, heating (> $400^{\circ}C$) of urea is the common method used for preparing the g-$C_3N_4$. We have found that sonication of melamine in $HNO_3$ solution, followed by washing with anhydrous ethanol, not only reduce the crystallite size of g-$C_3N_4$ but also facilitate intriguing electronic structure and photoluminescence (PL) properties. Moreover, loading of metal (Pt and Ag) nanoparticles, by applying the borohydride reduction method, has resulted in multicolor-emission from g-$C_3N_4$. With the help of PL spectra and local electronic structure study, at C K-edge, N K-edge, Pt L-edge and Ag K-edge by X-ray absorption spectroscopy (XAS), a precise mechanism of tunable luminescence is established. The PL mechanism ascribes the amendments in the transitions, via defect and/or metal states assimilation, between the ${\pi}^*$ states of tris-triazine ring of g-$C_3N_4$ and lone pair states of nitride. It is evidenced that interaction between the C/N 2p and metal 4d/5d orbitals of Ag/Pt has manifested a net detraction in the ${\delta}^*{\rightarrow}LP$ transitions and enhancement in the ${\pi}^*{\rightarrow}LP$ and ${\pi}^*{\rightarrow}{\pi}$ transitions, leading to broad PL spectra from g-$C_3N_4$ organic semiconductor compound.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제55권6호
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• pp.875-885
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• 2022

This study was performed to confirm the optimal extraction method for antimicrobial peptides from the Hard-shelled mussel. Extractions were performed with two processes including 1% HAc/boiling and 1% HAc/non-boiling methods and used extracts for the comparison of the antimicrobial activity, protease stability, action mechanism, AU-PAGE (acid-urea PAGE), and HPLC chromatograms. 1% HAc/boiling extract showed potent antibacterial activities both against Gram-positive and negative bacterium but 1% HAc/non-boiling extract showed antibacterial activity only against Gram-positive bacteria. Treatment of 1% HAc/boiling extract with proteases retained almost antibacterial activity against B. subtilis, but abolished significant antibacterial activity against E. coli D31. Only 1% HAc/boiling extract showed two discrete clearing antibacterial zones including slow migrating and rapid migrating zones. Both extracts showed strong DNA-binding ability but did not show bacterial membrane permeabilizing ability. In comparison of the chromatogram obtained from C₁₈ or cation-exchange HPLC, the eluted peaks from 1% HAc/boiling extract showed high hydrophobic property or absorbance compared to 1% HAc/non-boiling extract, respectively. The concentration of the purified antimicrobial peptide was also higher in 1% HAc/boiling extract than in 1% HAc/non-boiling extract. Our results suggest that the effective extraction condition for antimicrobial peptides from marine invertebrate is boiling process in a weak acetic acid solution (1%).