• Transactions of Materials Processing
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• v.14 no.8 s.80
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• pp.712-717
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• 2005

Microstructure and mechanical properties are investigated for 0.15C-1.5Mn-1.5Al TRIP aided cold rolled steels containing $0.05wt\%P$ and $0.1wt\%P$. Despite of the complete replacement of Si by Al, the TRIP steel shows tensile strength of 700MPa and total elongation of $35\%$ by addition of $0.1wt\%$ P. Tensile strength of P added TRIP steels is not only affected by the solid solution hardening but also the volume fraction of retained austenite. As P content increases from $0.05wt\%$ to $0.1wt\%$, tensile strength and volume fraction of retained austenite are increased, but elongation is decreased. The lower stability of austenite in $0.1wt\%$ P added steel is responsible for the decrease of the elongation.

• Bulletin of the Korean Mathematical Society
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• v.47 no.1
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• pp.211-219
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• 2010

Let P be a Jacobian polynomial such as deg P = $deg_y$ P. Suppose the Jacobian polynomial P satisfies the intersection condition satisfying $dim_C$ C[x, y]/$P_y$> = deg P - 1, we can prove that the Keller map which has P as one of coordinate polynomial always has its inverse.

• KSBB Journal
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• v.14 no.1
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• pp.58-65
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• 1999

A hydrogel, poly(N-isopropylacrylamide-co-N,N'-dimethylaminopropyl methacrylamide), sensitive to both pH and temperature was synthesized and characterized for its welling behavior, lower critical solution temperature (LCST), and its appearance. The hydrogel with 5 mol% of N,N'-diemthylaminopropyl methacrylamide (DMAPMAAm) increased its volume phenomenonally in a lower pH range (ph 1~8) even at temperature ($37^{\circ}C$ and $40^{\circ}C$) higher than LCST. This behavior was unique compared to the temperature -sensitive hydrogel which did not exhibit any swelling in the same pH range. The hydrogel with 20 mol% of DMAPMAAm was swollen significantly at a higher pH of 12. With pH decrease from 12 to 2 water content in the gel increased from 38.8 wt% and 60.6 wt%, and 90.8 wt% for 5 mol% and 20 mol% gel, respectively. The transition pH that pH effect overwhelmed temperature effect occurred at a lower pH for a higher temperature ($40^{\circ}C$) and a lower mol% (5 mol%) of DMAPMAAm. Transparency and LCST of the gel increased with higher DMAPMAAm mol%.

• Journal of the Korean Mathematical Society
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• v.42 no.1
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• pp.111-127
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• 2005

Let B and S be the unit ball and the unit sphere in $\mathbb{C}^n$, respectively. Let ${\sigma}$ be the normalized Lebesgue measure on S. Define the Privalov spaces $N^P(B)\;(1\;<\;p\;<\;{\infty})$ by $$N^P(B)\;=\;\{\;f\;{\in}\;H(B) : \sup_{0 where H(B) is the space of all holomorphic functions in B. Let ${\varphi}$ be a holomorphic self-map of B. Let ${\mu}$ denote the pull-back measure ${\sigma}o({\varphi}^{\ast})^{-1}$. In this paper, we prove that the composition operator $C_{\varphi}$ is metrically bounded on $N^P$(B) if and only if ${\mu}(S(\zeta,\delta)){\le}C{\delta}^n$ for some constant C and $C_{\varphi}$ is metrically compact on $N^P(B)$ if and only if ${\mu}(S(\zeta,\delta))=o({\delta}^n)$ as ${\delta}\;{\downarrow}\;0$ uniformly in ${\zeta}\;\in\;S. Our results are an analogous results for Mac Cluer's Carleson-measure criterion for the boundedness or compactness of $C_{\varphi}$ on the Hardy spaces $H^P(B)$.

• Journal of Microbiology
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• v.35 no.1
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• pp.53-60
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• 1997

Pseudomonas sp. P20 and Pseudomonas sp. DJ-12 isolated from the polluted environment are capable of degrading biphenyl and 4-chlorobiphenyl (4CB) to produce benzoic acid and 4-chlorobenzoic acid (4CBA) respectively, by pcbABCD-encoded enzymes. 4CBA can be further degraded by Pseudomonas sp. DJ-12, but not by Pseudomonas sp P20. However, the meta-cleavage activities of 2, 3-dihydroxybiphenyl (2, 3-DHBP) and 4-chloro-2, 3-DHBP dioxygenases (2, 3-DHBD) encoded by pcbC in Pseudomonas sp. P20 were stronger than Pseudomonas sp. DJ-12. In this study, the pcbC gene encoding 2, 3-DHBD was cloned from the genomic DNA of Pseudomonas sp. P20 by using pKT230. A hybrid plasmid pKK1 was constructed and E. coli KK1 transformant was selected by transforming the pKK1 hybrid plasmid carrying pcbC into E. coli XL1-Blue. By transferring the pKK1 plasmide of E. coli KK1 into Pseudomonas sp. DJ-12 by conjugation, a recombinant strain Pseudomonas sp. P20, Pseudomonas sp. DJ-12, and the recombinant cell assay methods. Pseudomonas sp. DJ12-C readily degraded 4CB and 2, 3-DHBP to produce 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoic acid (HOPDA), and the resulting 4CBA and benzoic acid were continuously catabolized. Pseudomonas sp. DJ12-C degraded 1 mM 4CB completely after incubation for 20 h, but Pseudomonas sp. P20 and Pseudomonas sp. DJ-12 showed only 90% and Pseudomonas sp. DJ-12 had, but its degradation activity to 2, 3-DHBP, 3-methylcatechol, and catechol was improved.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.275-282
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• 1998

To investigate the increased acid tolerance of a acid-resistant mutant Leuconostoc paramesenteroides P-100 improved as a kimchi starter, proton permeability, ATPase acitivity, glycolysis activity, $Mg^2$sup +/ releasement, and membrane fatty acid composition were studied and comprised with its wild type Leuconostoc paramesenteroides Pw. In the proton permeability experiment, the maximum values of the average half time (t$\_$1/2/) of pH equilibration through the cell membrane of the Pw and the P-100 were about 6.4 min and 7.8 min in 150 mM KCI solution, respectively. In the 3% NaCl solution, the t$\_$1/2/ values of the Pw and the P-100 were 5.5 min and 6.9 min, respectively. The values and pHs of maximal specific activities of ATPase originated from the Pw and the P-100 were 0.5 unit/mg protein and 0.78 unit/mg protein at pH 6.0, respectively. The result of pH dependence of glycolysis showed that the P-100 had higher activities than that of Pw except at pH 7.0. The releases of magnesium from the Pw and the P-100 were observed about 54.5% and 23.2% at pH 4.0 after 2 hours, respectively. The results of comparison of membrane fatty acid composition of the Pw with the P-100 showed that C$\_$8:0/, C$\_$9:0/, C$\_$10:0/, C$\_$11:0/, C$\_$18:0/, and C$\_$19:0,cyclo/ were major different fatty acids between two strains and the content of C$\_$18:1/, and C$\_$19:0,cyclo/ were 2.8%, N.D (not detected) in the Pw and 0.4%, 2.3% in the P-100. These results indicated that acid tolerance of the P-100 was significantly improved in comparison with its wild type Pw.

• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.581-587
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• 2013

The amounts of carbon (C), nitrogen (N) and phosphorus (P) in relation to dry weight (D.W.) were measured in zooplankton from the large four rivers (Han R., Geum R., Yeongsan R. and Seomjin R.) during 2004~2008. The stoichiometry of total zooplankton in four river systems was highly variable. The ranges of average C, N and P-contents were $70{\sim}620mgC\;mg^{-1}$ D.W., $7.1{\sim}85.5{\mu}gN\;mg^{-1}$ D.W. and $2.5{\sim}7.4{\mu}gP\;mg^{-1}$ D.W., respectively. The mean C :N: P atomic ratios reflected large spatial differences. The C : P and N : P ratios of the zooplankton community ranged from 38 to 392 : 1 and from 4 to 65 : 1 in all sampling sites. Self-Organizing Map (SOM) was applied to the survey data, and the study sites were clearly classified into 3 clusters. Clustering was largely affected by the distribution pattern of C, N, P-contents, which is related with characteristics of river systems on the basis of stoichiometry.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.107-111
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• 2006

본 연구는 돼지 품종에 따른 지방 함량, 지방산 조성 및 전자코에 의한 향기 패턴의 차이를 분석하고자 실시하였으며, 평균 생시체중이 111 kg인 멧돼지 5두, 64 kg인 재래흑돼지 5두 및 114 kg인 개량종 돼지($Landrace{\times}Yorkshire$) 5두의 등심(M. longissimus) 부위를 본 실험에 이용하였다. 근내 지방함량은 재래흑돼지가 멧돼지, 개량종 돼지보다 유의적으로 높았다(p<0.05). 지방산 조성에서 C14:0, C18:3n3, MUFA/SFA 비율은 재래흑돼지가 가장 유의적으로 높았으며(p<0.05), C18:1n9는 개량종 돼지가 멧돼지보다 높았다(p<0.05). C16:1n7, C18:1n7, UFA/SFA 비율은 멧돼지가 가장 높았으며(p<0.05), C18:0, C20:1n9는 멧돼지가 가장 낮았다(p<0.05). C20:4 n6은 멧돼지가 개량종 돼지보다 높았고(p<0.05), C22:4n6은 재래흑돼지가 가장 높았으며(p<0.05), C22:5n3은 멧돼지가 재래흑돼지보다 높았다(p<0.05). PUFA n6/n3 비율은 개량종 돼지가 가장 낮았으며(p<0.05), 멧돼지가 재래흑돼지보다 낮았다(p<0.05). 전자코의 PCA에 의한 향기패턴은 신선육에서 품종에 따른 차이가 명확히 나타났으며, 가열육에서는 멧돼지 및 재래흑돼지, 개량종 돼지간에 차이가 나타났다. 따라서 재래흑돼지가 가장 높은 근내 지방 함량 및 가장 낮은 MUFA/SFA 비율을 가졌고, 멧돼지가 가장 높은 UFA/SFA 비율을 가졌으며, 개량종 돼지가 가장 낮은 PUFA n6/n3 비율을 가졌다. 또한 전자코에 의해 돼지 품종에 따른 돈육의 향기 패턴 차이를 효과적으로 분별할 수 있었다.

• Journal of the Korean Magnetics Society
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• v.4 no.1
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• pp.7-11
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• 1994

Ferromagnetic resonance experiment was performed to study the variations of micromagnetic structure with heat treatment of melt spun $Fe_{76}Cu_{1}Nb_{3}Si_{14}B_{6}$ alloy for 1h at every $50^{\circ}C$ in the temperature range of $400^{\circ}C-700^{\circ}C$. The variations of micromagnetic structure was discussed qualitatively in terms of the variations of line width ${\Delta}H_{p-p}$ and resonance magnetic field $H_{res}$. With increasing armealing temperature to $400^{\circ}C$, ${\Delta}H_{p-p}$ decreases and $H_{res}$ increases due to the decrease in magnetic anisotropy resulting from structural relaxation during heat treatment. With increasing annealing temperature from 400 to $500^{\circ}C$, ${\Delta}H_{p-p}$ increases and $H_{res}$ decreases due to the increase in magnetic anisotropy resulting from the formation of nanocrystalline particles embedded in an amorphous matrix. With increasing armealing temperature from 500 to $550^{\circ}C$, ${\Delta}H_{p-p}$ decreases and $H_{res}$ increases due to the decrease in magnetic anisotropy resulting from the formation of homogeneous nanocrystalline structure with a minor amorphous phase. Further increase in armealing temperature above $550^{\circ}C$ C causes ${\Delta}H_{p-p}$ to increase and $H_{res}$ to decrease due to the increase in magnetic anisotropy due to the formation of inhomogeneous grain structure and intermetallic compounds.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.624-631
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• 2014

In this study, a new series of conjugated polymer 3-(5-(5,6-bis(octyloxy)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-10-(4-(octyloxy)phenyl)-10H-phenothiazine (P1) and 3-(5-(5,6-bis(octyloxy)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-10-(4-((2-ethylhexyl)oxy)phenyl)-10H-phenothiazine (P2) were synthesised and organic photovoltaics (OPVs) properties were characterized. The push-pull structure polymer consisted of phenothiazine derivative as an electron donor and benzothiadiazole derivative as an electron acceptor. The aliphatic chain substituted aromatic ring was substituted at the position of N in phenothiazine for the electron-rich and improved solubility. Excellent thermal stabilities of P1 and P2 were confirmed by measured Td values as 321.9 and $323.7^{\circ}C$, respectively and the degrees of polymerization were 4,911 (P1) and 5,294 (P2). The maximum absorption wavelength of P1 and P2 were 549 and 566 nm, respectively. The device was fabricated and the OPVs property was measured. As a result, the power efficiency of conversion for P1 and P2 were 0.96 and 0.90%, respectively.