• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.282-288
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• 1996

Because of the high water content of the household garbage, it is difficult to compost it. Therefore, this study was conducted to investigate the possibility of using coal fly ash as humidity conditioner for the household garbage composting. The summarized results are as follows : 1. The maximum temperatures were $35^{\circ}C$ in spring, $47^{\circ}C$ in summer, and $43^{\circ}C$ in winter during the composting periods. 2. The mass was reduced to 70.5% after 60 days. The average volume reduced down to 74.7% after 60 days. 3. The seasonal variation of pH values showed a similar tendency and reached 8.5 after 60 days. 4. The water content was reduced at an early stage of composting and not much changed thereafter. It had 49.7% in spring, 33.9% in summer, and 56.5% in winter after 60 days. Ash contents were not much changed during the composting periods. 5. The contents of inorganic compounds were in the range of $0.06{\sim}4.03%$ $P_2O_5$, $0.01{\sim}2.87%$ CaO, $0.18{\sim}1.43%$ MgO, and $0.39{\sim}2.03%$ $K_2O$. Heavy metal contents were in the range of $ND{\sim}14.08$ Hg ${\mu}g/kg$, $ND{\sim}0.80$ Cd mg/kg, $4.99{\sim}28.95$ Cu mg/kg, $ND{\sim}242.62$ Cr mg/kg, $ND{\sim}20.24$ Pb mg/kg, and $ND{\sim}59.87$ Zn mg/kg.

• Journal of the Korean Magnetics Society
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• v.11 no.6
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• pp.250-255
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• 2001

Magnetic properties of the isotropic and anisotropic NdFeB magnets obtained by the Current-Applied Pressure-Assisted (CAPA) process from a melt-spun NdFeB powder were investigated using B-H loop analyser. The coercivity of the isotropic magnets is sensitive to the applied pressure in the CA-pressing and increases with increasing the pressure. The remanence of the anisotropic magnet increases with increasing the degree of deformation, and it results in the increase of a maximum energy Product. The best magnetic Properies of the isotropic and anistropic magnet are B$\sub$r/= 8.7 kG, $\sub$i/H$\sub$c/= 16.9 kOe, (BH)$\sub$max/= 16.5 and B$\sub$r/= 13.6 kG, $\sub$i/H$\sub$c/= 10.9 kOe, (BH)$\sub$max/= 44.2 MGOe, respectively.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.45-49
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• 2008

Purpose: To evaluate the recovery time of biochemical changes of body after half-course marathon running. Materials and methods: Thirteen amateur half course marathon runners (12 males and 1 females) were studied. Their average age was 44 years old (range: $38{\sim}54$). Biochemical parameters with blood test including AST, ALT, CK-MB, Treponin, BUN, Cr Na, K were evaluated at finish line, 2nd days, 2nd weeks after running. Results: All the biochemical changes were within normal range throughout recovery time, AST reached its maximum level at finish line and continued until 2nd day after running and returned its pre-running level at 2nd week's test. CK-MB reached its maximum level 2nd day after running and recovered at 2nd week's test. Na, K, BUN and Cr reached to the maximum level at finish line, and recovered to pre-running level at 2nd day's test. Conclusion: In case of half-course marathon, the changes of the kidney enzymes due to dehydration were recovered after 2nd day. And the biochemical indicators of muscle fatigue recovered after 2nd week. It needs at least 2 weeks rest after half-course marathon to recover all the biochemical parameter of the body.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.326-326
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• 2007

Influence of $Nd_2O_3$ addition to $ZnO-B_2O_3$-based glass on the water leaching resistance of the glass was first investigated. The optimized $Nd_2O_3-ZnO-B_2O_3$ (NZB) glass was ball milled for varying time, mixing with followed by $Al_2O_3$ crystalline phase to form $Al_2O_3$-NZB glass composites at $875^{\circ}C$ for 1h. Microwave dielectric properties of the composites were investigated as a function of the ball milling time of the NZB glass. Dielectric constant and quality factor were 5.70 and 9497 GHz, respectively, when the NZB glass was ball milled for 6h prior to mixing with $Al_2O_3$.

• Progress in Superconductivity and Cryogenics
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• v.11 no.2
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• pp.1-6
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• 2009

We report a successful fabrication of $high-J_c\;NdBa_2Cu_3O_{7-{\delta}}$ (NdBCO) films on $SrTiO_3$(STO) (100) substrates by pulsed laser deposition (PLD) in a relatively wide processing window. Under various oxygen pressures controlled by either 1%$O_2$/Ar mixture gas or pure $O_2$ gas, strongly c-axis oriented NdBCO films were grown at the substrate temperature $(T_s)\;of\;800^{\circ}C$ in 800 mTorr with 1%$O_2$/Ar gas and also in 400 and 800 mTorr with pure $O_2$ gas. These samples exhibited $T_c$ values over 90K and $J_c$ values of $2.8-3.5MA/cm^2$ at 77K in self-field (77K, sf). On the other hand, $J_c$ values over $1A/cm^2$ were obtained at the temperature regions of $700-830^{\circ}C$ in 800 mTorr with 1%$O_2$/Ar gas at those of $750-830^{\circ}C$ in 800 mTorr with pure $O_2$ gas. Unlike previous reports, resent results support that the PLD processing window for high-Jc NdBCO films is not narrow.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.63-67
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• 1997

환원확산법은 저렴한 Nd 산화물을 환원제를 이용하여 환원시키고 환원된 Nd가 Fe, FeB와 확산하여 주상인 Nd$_2$Fe14B가 만들어지는 공정으로 환원제로 사용된 CaO나 미반응 Ca 및 잔존 산소함량을 조절하는데 어려움이 있어 아직까지는 상업되지 못하고 있는 실정이다. 본 연구에서는 환원확산법을 이용하여 Nd-Fe-B계 영구자석에 사용될 미세분말을 제조하고 그 자기적 특성을 관찰하였다.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.245-250
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• 2010

The post-harvest concentration change of four kind of pesticides, captan, chlorpyrifos, methidathion and kresoxim-methyl was investigated with the storage period for the import fruit. Then the post-harvest concentration was set to 1000, 250, 400 and 157 $mgkg^{-1}$ for captan, chlorpyrifos, methidathion and kresoxim-methyl respectively. In case of captan, 0.9-12.5 $mgkg^{-1}$ in total fruit base and ND-0.23 $mgkg^{-1}$ in the sarcocarp were measured after atomization and 0.7-3.2 $mgkg^{-1}$ in total fruit base and ND-0.67 $mgkg^{-1}$ in the sarcocarp were measured after four week. For chlopyrifos, menthidathion, and kresoxim-methyl 0.4-2.2, 0.7-3.1 and 1.3-2.1 $mgkg^{-1}$ in total fruit base and ND-0.32, ND-0.05 and ND-0.16 $mgkg^{-1}$ in the sarcocarp were measured after atomization respectively. After four week 0.3-0.9, 0.4-2.0 and 1.3-1.8 $mgkg^{-1}$ in total fruit base and ND-0.02, ND-0.05 and ND-0.15 $mgkg^{-1}$ in the sarcocarp were investigated for other three pesticides. The concentration decreasing ratio of pesticides was largest for captan, 52% and other components were in order of chlopyrifos, menthidathion, and kresoxim-methy, 47, 41, 11% each other.

• Journal of the Korean earth science society
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• v.22 no.1
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• pp.1-9
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• 2001

Composition of the major and trace elements, Rb-Sr isochron age Sr-Nd isotope composition were determined for foliated in the Jeonju area, in the middle part of the Ogcheon Fold Bet, Korea. The geochemical characteristics of the Jeonju foliated granite indicate that the granite had been crystallized from a calc-alkaline series, and formed in a volcanic are environment. The isotopic compositions of the Jeonju foliated granite give Rb-Sr whole rock errorchron age of 168.2${\pm}$8 Ma(2${\sigma}$), corresponding to the middle Jurassic period, with the Sr initial ratio of 0.71354${\pm}$0.00031. $^{143}$Nd/$^{144}$Nd ratios, ${\varepsilon}$Nd and ${\varepsilon}$Sr values range from 0.511477 to 0.511744, -15.4${\sim}$-21.2, and +108.8${\sim}$+l42.6, respectively. Model ages were caculated to be 1.82${\sim}$2.89Ga. The isotopic data of Jeonju foliated granite indicate that the source material may have been derived from partial melting of continental crust materials.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.937-946
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• 2004

Duroc is widely used to improve the meat quality and productivity. To elucidate the phylogenetic relation and the sequence specificity for the maternal property, the complete sequence of mitochondrial genome was determined and the population diversity of Duroc was investigated in this study. The length of mtDNA tested is 16,584-bp. There are several insertion/deletion mutations in the control region and coding regions for tRNA and rRNA, respectively, but not in peptide-coding regions. Four peptide-coding genes(COⅡ, COⅢ, ND3 and ND4) showed incomplete termination codon sequences such as T--, and two(ND2 and ND4L) did alternative initiation codons(AIC), respectively. Especially, the initiation codon sequences of ND2 gene were polymorphic in this population. Polymorphisms were detected in 11-bp duplication motif within control region as well as ND2 and CYTB. Variation patterns observed from the tests on three mtDNA regions were linked completely and then two haplotypes obtained from combining the data dividing this population. Duroc mtDNA is observed at the European pig cluster in the phylogenetic tree, however, the results from the population analyses supported previous opinions. This study suggests that the breed Duroc was mainly originated from the European pig lineage, and Asian lineage was also used to form the pig breed Duroc as maternal progenitors.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1247-1264
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• 2021

Anabolic steroids are frequently used to increase the growth rate of meat-producing animals. Exposure to an anabolic-androgenic steroid, nandrolone decanoate (ND), is associated with expressional reduction of testicular steroidogenic enzymes. However, the effect of withdrawal of ND exposure on the expression of these testicular molecules has not been thoroughly explored. The current research investigated expression changes of testicular steroidogenic enzymes in rats at several recovery periods (2, 6, and 12 weeks) after the stop of ND treatment with different doses (2 and 10 mg/kg body weight) for 12 weeks. Body and testis weights were recorded, and transcript levels of molecules were determined by quantitative real-time polymerase chain reaction (PCR). The immunohistochemistry was used to examine the changes of immuno-intensities of molecules. At 6 and 12 weeks of the recovery period, the 10 mg/kg ND-treated rats were lighter than other experimental groups. The interstitial compartment vanished by ND treatment filled up as the recovery period became longer. The expression of steroidogenic acute regulatory protein was returned to the control level at 12 weeks of the recovery period. Expression levels of cytochrome P450 side-chain cleavage and 17a-hydroxylase were increased in 2 mg/kg ND-treated group at 6 weeks of the recovery period, and transcript levels of these molecules in 2 and 10 mg/kg ND-treated groups at 12 weeks of the recovery period were significantly lower than the control. Expression levels of 3β-hydroxysteroid dehydrogenase (HSD) type I and 17β-HSD type 3 in 2 mg/kg ND-treated group were comparable with those of control at 12 weeks of the recovery period, but not in 10 mg/kg ND-treated group. Expression of cytochrome P450 aromatase (Cyp19) was reverted to the control level at 2 weeks of the recovery period. Except for Cyp19, there was a visible increase of immuno-staining intensity of other testicular steroidogenic enzymes in the Leydig cells as the recovery period progressed. This research has demonstrated that the cease of ND administration could restore the expression of testicular steroidogenic enzymes close to the normal level. Nevertheless, a relatively long recovery period, compared to the ND-exposure period would be required to retrieve normal expression levels of testicular steroidogenic enzymes.