• 대한화학회지
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• 제45권5호
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• pp.436-441
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• 2001

77K에서 mer-[Cr(dien)(glygly)]$ClO_4$의 방출 및 들뜬 상태 스펙트럼과 실온에서 적외선 및 가시선 스펙트럼을 측정하였다. 스핀-허용 및 스핀-금지에 해당하는 12개의 전자 전이의 성분을 배정하였다. 관측한 전이를 이용하여 Cr(Ⅲ) 착물에 배위된 원자의 결합성을 결정하기 위해서 리간드장 해석을 수행하였다. 이 연구에서 dien과 glygly 리간드의 아민 N 원자는 강한 $\sigma$-주개 특성을 갖는 반면에, glygly의 펩티드 N 원자는 Cr(Ⅲ) 이온에 약한 $\pi$-주개의 성질이 있음을 확인할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제20권3호
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• pp.314-320
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• 1999

Several bisphosphine- and bisphosphite-substituted Re-imido complexes have been prepared from Re(NPh)(PPh3)2Cl3, 1, and Re(N-C6H3-i-Pr2)2Cl3(py), 4. Compound 1 reacted with trimethyl phosphate (P(OMe)3) to give a mixture of two isomers,mer,trans-Re(NPh)(P(OMe)3)2Cl3, 2, and fac,cis-Re(NPh)(P(OMe)3)2Cl3, 2a. In this reaction, the mer,trans-isomer is a major product. Complex 1 also reacted with triethylphosphine (PEt3) to exclusively give mertrans-Re(NPh)(PEt3)2Cl3, 3. Compound 4 reacted with trimethylphosphine (PMe3) to give mer,trans-Re(N-C6H3-i-Pr2)(PMe3)2Cl3, 5, which was converted to mer-Re(N-C6H3-i-Pr2)(PMe)(OPMe3)Cl3, 6, on exposure to air. Crystallographic data for 2: monoclinic space group P21/n, a = 8.870(2) Å, b = 14.393(3) Å, c = 17.114(4) Å, β = 101.43(2)°, Z = 4, R(wR2) = 0.0521(0.1293). Crystallographic data for 5: orthorhombic space group P212121, a = 11.307(l) Å, b = 11.802(l) Å, c = 19.193(2) Å, Z = 4, R(wR2) = 0.0250(0.0593). Crystallographic data for 6: orthorhombic space group P212121, a = 14.036(4) Å, b = 16.486(5) Å, c = 11.397(3) Å, Z = 4, R(wR2) = 0.0261(0.0630).

• 설비공학논문집
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• 제21권1호
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• pp.1-8
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• 2009

The simulation of a heat pump dryer has been carried out to figure out the effect of air flow rate on the drying performance represented by MER, SMER, and so on. The simulation includes the analyses of one-stage heat pump cycle and simple drying process using the drying efficiency. The heat pump cycle with Refrigerant 134a has been considered. In the dryer, some of drying air from the drying chamber flows through the heat pump system, the rest of air bypasses the heat pump system. The two air flows joins before the drying chamber inlet. The performance parameters considered in the present study are MER, SMER, the temperature and humidity of drying air. Those parameters are compared for different total air flow rate or bypass air flow rate.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.303-307
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• 2006

We have screened phage display peptide libraries to select for peptides binding to various sized $TiO_2$ nanoparticles. Phage libraries displaying random 7mer, 12mer, and C-7-Cmer peptides were used for screening. The size of target $TiO_2$ particles used were 7 nm, 15 nm, and 25 nm in diameter. We could select peptides binding each nanoparticles from all 3 libraries. Their binding was confirmed by transmission electron microscopy (TEM). Each peptide investigated was also shown to bind the other sized particles, meaning that the binding was specific for the nature of the particle rather than for the size of it. One of the 7mer peptides (PEP9, SVSPISH) was chosen for further analysis. The binding was shown to be in a dose-dependent manner, suggesting a specific interaction.

• Asian-Australasian Journal of Animal Sciences
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• 제23권2호
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• pp.240-245
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• 2010

The effects of controlled energy restriction and duration of pre-incubation egg holding on fertility, hatchability and hatch losses were evaluated in aged broiler breeders (64 wk). The energy (ME) required for maintenance, activity, growth and anticipated egg production was calculated and offered to a control group (283-471 kcal/kg) from 21-64 weeks of age. In three other groups, ME was quantitatively reduced either by 20% (SER; severe energy restriction) or 10% (MER; moderate energy restriction) and increased by10% (EEF; excess energy feeding) over the control group (CER; controlled energy restriction). Each diet was offered to 130 pullets in individual cages, and the quantity of ME increased with age. At the end of 64 weeks, fertile eggs were collected from each dietary group for 11 consecutive days and grouped under 4 holding periods based on the length of storage (2, 5, 8 or 11 d). The influence of energy regimes, egg holding intervals and their interaction was evaluated on fertility, hatch losses and hatchability. Broiler breeders maintained on SER regime (231-419 kcal/d) produced maximum number of eggs (993) followed by MER (819), CER (624) and EEF (438) during the 11-day period. The percent fertility and hatchability was significantly (p$\leq$0.05) higher in SER and MER groups compared to CER and EEF. However, energy regimes did not influence the loss in egg weight during pre-incubation storage, shell weight, shell thickness or hatch losses as dead germs and dead in shell. The improvement in hatchability in SER and MER groups appeared to be closely related to higher fertility and lower embryonic mortality. Holding of eggs for 11 days showed a linear loss in egg weight with the length of storage, but did not influence the fertility and hatch losses. The percent hatchability on eggs set was maximum when storage period was restricted to 5 days. The interaction between energy regimes and egg holding periods exhibited better hatchability results with SER regime when eggs were held for 5 days. Response to MER was not different from SER. It was obvious that energy restriction during production period had a positive influence on egg number, fertility and hatchability in aged breeders. At 64 weeks of age, holding of fertile eggs for 5 days prior to incubation was adequate for optimum hatchability in breeders.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.1-13
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• 2011

9Pbw2 is a 9-mer analog of protaetiamycine derived from the larvae of the beetle Protaetia brevitarsis. Previously, we designed four 9-mer peptide analogues to optimize the balance between the hydrophobicity and cationicity of the peptides and to increase bacterial cell selectivity. Among them, 9Pbw2 has high antibacterial activity without cytotoxicity. The results obtained in previous study suggest that the bactericidal action of 9Pbw2 may be attributed to the inhibition of the functions of intracellular components after penetration of the bacterial cell membrane. In order to understand structure-activity relationships, we determined the three-dimensional structure of 9Pbw2 in 200 mM DPC micelle by NMR spectroscopy. 9Pbw2 has one hydrophobic turn helix from $Trp^3$ to $Arg^8$ and positively charged residues at the N- and C-terminus. This result suggested that positively charged residues from position at the C-terminus in 9Pbw2 may be important for the primary binding to the negatively charged phospholipid head groups in bacterial cell membranes and hydrophobic residues in the middle portion face toward the acyl chains of the hydrophobic lipid in the bacterial cell membrane.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1375-1376
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• 2007

A synthesized 21-mer single-stranded DNA(ss DNA) was covalently immobilized onto a self-assembled aminoethanethiol monolayer modified gold electrode onto QCM. The covalently immobilized ssDNA was hybridized with complementary ssDNA. The interaction between surface immobilized ssDNA and complementary 21-mer DNA in solution was also examined. Each step was followed by monitoring changes in the QCM frequency with time. Also, PBS with pH 7.0 was selected as a supporting electrolyte in order to get maximum sensitivity and good bioactivity.

• BMB Reports
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• 제29권3호
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• pp.236-240
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• 1996

A 23-kDa molecular mass of antioxidant protein was purified from human liver. This protein exhibited the preventive effect against the inactivation of glutamine synthetase by a metal-catalyzed oxidation system. This antioxidant activity was supported by a thiol-reducing equivalent such as dithiothreitol in a similar manner to that of the 25-kDa thiol-specific antioxidant protein (TSA) from human red blood cells (HR). However, a thioredoxin-linked peroxidase activity of thiol-specific antioxidant protein of human liver (HLTSA) (0.91 ${\mu}mol/min/nmol$ of HLTSA) was much lower than that of thiol-specific antioxidant protein of human red blood cells (HRTSA) (16.4 ${\mu}mol/min/nmol$ of HRTSA). This HLTSA is also immnologically distinct from HRTSA Amino acid sequences of the three tryptic peptides (P1, P2, P3) of HLTSA were found to be completely homologous to segments of the known Mer5-like protein, which belongs to the known TSA family.

• 대한기계학회논문집B
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• 제31권10호
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• pp.860-867
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• 2007

Heat pump drying has a great potential for energy saving due to its high energy efficiency in comparison with conventional air drying. In the present study, the performance simulation for the basic design of a heat pump dryer has been carried out. The simulation includes one-stage heat pump cycle, simple drying process using the drying efficiency. As an example, the heat pump cycle with Refrigerant 134a has been investigated. For the operating conditions such as the average temperature of the condenser, the heat rate released in the condenser, the flow rate of drying air, and drying efficiency, the simulation has been carried out to figure out the performance of the dryer. The parameters considered in the design of the dryer are COP, MER, SMER, the rate of dehumidification, the temperature and humidity of drying air and those parameters are compared for different conditions after carrying out the simulation.

• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.742-753
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• 2012

Copper-containing compounds are introduced into the environment through agricultural chemicals, mining, and metal industries and cause severe detrimental effects on ecosystems. Certain microorganisms exposed to these stressors exhibit molecular mechanisms to maintain intracellular copper homeostasis and avoid toxicity. We have previously reported that the soil bacterial isolate Achromobacter sp. AO22 is multi-heavy metal tolerant and exhibits a mer operon associated with a Tn21 type transposon. The present study reports that AO22 also hosts a unique cop locus encoding copper homeostasis determinants. The putative cop genes were amplified from the strain AO22 using degenerate primers based on reported cop and pco sequences, and a constructed 10,552 base pair contig (GenBank Accession No. GU929214). BLAST analyses of the sequence revealed a unique cop locus of 10 complete open reading frames, designated copSRABGOFCDK, with unusual separation of copCD from copAB. The promoter areas exhibit two putative cop boxes, and copRS appear to be transcribed divergently from other genes. The putative protein CopA may be a copper oxidase involved in export to the periplasm, CopB is likely extracytoplasmic, CopC may be periplasmic, CopD is cytoplasmic/inner membrane, CopF is a P-type ATPase, and CopG, CopO, and CopK are likely copper chaperones. CopA, B, C, and D exhibit several potential copper ligands and CopS and CopR exhibit features of two-component regulatory systems. Sequences flanking indicate the AO22 cop locus may be present within a genomic island. Achromobacter sp. strain AO22 is thus an ideal candidate for understanding copper homeostasis mechanisms and exploiting them for copper biosensor or biosorption systems.