• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.331-337
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• 1999

Cracks on the cylinder block of diesel engines will often happen due to cyclic load and thermal stress. According to the Classification Societies' rules welding reparis of cylinder block made of cast irons are generally not permitted. However such welding repairs became inevitable taking enormous cost and time for their renewal into consideration. In this study repair welding methods for the clinder blocks made of gray cast irons were reviewed and the tests of their welds were carried out in order to purpose the repair welding meth-ods of packing seat and o-ring seat of cylinder block and apply them to the practice. The following conclusions are botained :1 The tensile strength of weld of cast iron more than that of base metal can be obtained by means of preheating keeping temperature above $100^{\circ}C$ between welding pass-es preventing slag inclusion peening and cramping weld metal by studs. 2. The suspected crack by a magnetic particle test due to different magnetic permeability can be identified which are not associated with a mechanical discotinuity.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.742-749
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• 2010

We investigated the antioxidant efficacy of quercetin (0% Diet 1, 0.25% Diet 2, and 0.5% Diet 3) pretreatment for 30 and 60 days in response to cadmium (Cd) toxicity in the olive flounder, and measured the plasma lysozyme activity to understand the immune effects of quercetin. The lysozyme activity with Diets 2 and 3 was higher than with Diet 1. Based on this result, to examine the immune ability and antioxidant role of quercetin, we exposed olive flounder fed quercetin to Cd and then measured the expression and activity of antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)) and lipid peroxidation (LPO). With Diets 2 and 3, the expression and activity of antioxidant enzymes and the $H_2O_2$ concentration were lower than with Diet 1. In addition, the LPO levels were lower than with Diet 1, which protected the cell membrane. Therefore, quercetin removed the reactive oxygen species (ROS) produced by Cd, indicating that quercetin has antioxidant ability. In addition to its antioxidant ability, quercetin has immune effects.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.05a
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• pp.23-27
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• 1997

Bio-Green(B.G.) functional water was manufactured by Kyungwon Enterprise Co. through a series of processes ; water longrightarrow ultra-purification longrightarrow adding catalysts longrightarrow energy imprinting fermenting with energized water + zeolite and others + photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters of B.G. functional water were supplied to the orchard soil under canopy of 10 year old 'Tsugaru'/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. Some orchard soil characteristics, not only pH, but also Ca and Mg of exchangeable cations were increased by supply with B.G. functional water. However, P$_2$O$_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh and anthocyanin of fruit skin were increased by the treatment. B.G. functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment showed higher Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit were decreased, while fruit firmness increased by the treatment during storage.e.

• Resources Recycling
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• v.8 no.3
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• pp.37-42
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• 1999

Ths sludy was canied out to recover gold and sllics from abandoned gold mine talings with about 4.5 ghonAu and 84.88 wt% SOz. Tl~bee nef~cialiop~ro~c esses including crushing, screening, magnelic and gravity (humprey sp~rals,h aking table) separation \ulcornervex employed. Results were Feasible to rccovn h e gold concentrates (307.1 gltoilon .4u . 0.60 wr%, 97.7 giton Au : 0.27 wl%, 15.3 &/ton Au . 5.23 wt%, 21.2 g/ton Au : 2.42 wl%) and silica (96.40 wi% SiO\ulcorner yield 60 65 ~ 1 % )

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.249-254
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• 1999

A catechol 2,3-dioxygenase (C23O) was purified to apparent homogeneity from Pseudomonas putida SU10 through several purification steps consisting of ammonium sulfate precipitation and chromatographies on DEAE 5PW, Superdex S-200, and Resource-Q. Gel filtration indicated a molecular mass under nondenaturing conditions of about 130 kDa. The enzyme has a subunit of 34 kDa as was determined by SDS-PAGE. These results suggest that the native enzyme is composed of four identical subunits. The N-terminal amino acid sequence (30 residues) of the enzyme has been determined and exhibits high identity with other extradiol dioxygenases. The reactivity of this enzyme towards catechol and methyl-substituted catechols is somewhat different from that seen for other catechol 2,3-dioxygenases, with 4-methylcatechol cleaved at a higher rate than catechol or 3-methylcatechol. $K_m$ values of the enzyme for these substrates are between 3.5 and 5.7 M.

• Progress in Superconductivity and Cryogenics
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• v.14 no.3
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• pp.23-27
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• 2012

This paper aims to evaluate the feasibility of using no-insulation High Temperature Superconducting (HTS) coil in persistent current mode system. A HTS coil in persistent current mode system usually includes one or more non-superconducting joints in its circuit. And the current decaying rate of the coil is affected by the resistance of joint in persistent current circuit. If the resistance of joint is large, decaying rate of the current drastically increases. Therefore, reducing the joint resistance of the HTS coil is very important in persistent current mode system. In this paper, the no-insulation HTS coil is suggested as a way to reduce the joint resistance with the embedded parallel contact resistance naturally made by no-insulation winding method. Two small coils are fabricated with insulation and no-insulation winding method, and persistent current mode system experiment of each coil is preformed and analyzed.

• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.23-26
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• 2007

The effects of plasma treatment on the ITO/glass substrate before deposition of organic materials were investigated in the fabrication of green light emitting organic devices with $Alq_3-C545T$ fluorescent system. In our experiments, the optimum plasma treatment was obtained at the power and time of 150W and 2 minutes under the $Ar(50%)/O_2$ ambient of 1 mTorr. The green OLED with plasma treatment at 150W for 2 minutes showed the luminance and efficiency of $4700\;cd/m^2$ and 8 lm/W at 10V, respectively. On the contrary, the same structured device without plasma treatment showed much lower performance with the luminance of $2600\;cd/m^2$ and the efficiency of 3.6 lm/W at 10 V.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.381-384
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• 2000

It is well recognized that physicochemical properties of drugs are affected by the type of polymorphic crystalline form of drugs. Clarithromycin is known to exist in at least three polymorphic crystalline forms. Since conventional means to obtain the most thermodynamically stable form (Form II) for the antibiotics is known to be associated with a low purity of the stable form, we developed a novel method to improve the purity of the crystalline form by a modification of the preparation process. The new method involved a simple recrystallization of clarithromycin in solvents having 5-12 carbon atoms (e.g., hexane and heptane) or ethers with 4-10 carbon atoms (e.g., isopropyl ether) and, thus, less likely to be associated with the problem in purity of resulting crystal. Differential scanning calorimetry and powder X-ray diffraction were used to compare the crystalline form of the resultant powder with Form IIcrystal prepared by the conventional method. The crystal prepared by the new method was identical to Form IIcrystal of the conventional method as evidenced by the lack of the exothermic peak near 11$0^{\circ}C$ in differential calorimetry scan, indicating that Form IIcrystal could be readily prepared by the new process. Therefore, these data indicated that the improvement in the purity of the Form IIcrystal for clarithromycin as well as a significant cost reduction is likely by the novel method.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.366-370
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• 1992

Salient chromosomal variations during the first meiotic division in primary spermatocyLes of the three brown planthopper, Nilaparvata lugens (Stal) , biotypes were observed. The meiotic index was highest in biotype 3 (58.6), followed by biotype 1 (39.4) and biotype 2 (23.6). Total chromosomal aberration including agmatoploidy, aneuploidy, loose pairings of sex chromosomes, and cytoplasmic shrinkage was found high in the order of biotype 1 (60.6%),2 (47.9 %), and 3 (38.1 %). However, percent agmatoploidy was highest in biotype 2 (19.6%) whereas in biotypes 3 and 1, it was 9.5% and 2.5%, respectively. The number of cells with isolated sex chrosomomes was observed highest in biotype 2.

• Journal of The Korean Astronomical Society
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• v.41 no.2
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• pp.23-37
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• 2008

The high-resolution optical region spectroscopic data of the symbiotic nova AG Peg secured with the Hamilton Echelle Spectrograph at the Lick Observatory, have been analyzed along with the International Ultraviolet Explorer UV archive data. We measure about 700 line intensities in the wavelengths of 3859 to $9230{\AA}$ and identify about 300 lines. We construct pure photoionization models that represent the observed lines and the physical condition for this symbiotic nova. The spectral energy distribution of the ionizing radiation is adopted from stellar model atmospheres. Based on photoionization models, we derive the elemental abundances; C & N appear to be similar to be smaller than the Galactic planetary nebular value while O is enhanced. Our result is compared with the Contini (1997, 2003) who analyzed the UV region spectral data with the shock + ionization model. The Fe abundance appears to be enhanced than that of normal planetary nebulae, which suggests that AG Peg may have formed in the Galactic disk. The models indicate that the temperature of the central star which excite the shell gas may have fluctuated to an unexpected extent during the years 1998 - 2002.