• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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• pp.97-117
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• 1995

Copper resistance in Pseudomonas syringae pv. tomato is determined by copper-resistance operon (cop) on a highly conserved 35 kilobase plasmid. Copper-resistant strains of Pseudomonas syringae containing the cop operon accumulate copper and develop blue clonies on copper-containing media. The protein products of the copper-resistance operon were characterized to provide an understanding of the copper-resistance mechanism and its relationship to copper accumulation. The Cop proteins CopA (72 kDa), CopB (39 kDa), and CopC (12 kDa) were produced only under copper induction. CopA and CopC were periplasmic proteins and CopB was an outer membrane protein. Leader peptide sequences of CopA, CopB, and CopC were confirmed by amino-terminal peptide sequencing. CopA, CopB, and CopC were purified from strain PT23.2, and their copper contents were determined. One molecule of CopA bound 10.9${\pm}$1.2 atoms of copper and one molecule of CopC bound 0.6${\pm}$0.1 atom of copper. P. syringae cells containing copCD or copBCD cloned behind the lac promoter were hypersensitive to copper. The CopD (32 kDa), a probable inner membrane protein, function in copper uptake with CopC. The Cop proteins apparently mediate sequestration of copper outside of the cytoplasm as a copper-resistance mechanism.

• 한국전기전자재료학회논문지
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• 제19권8호
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• pp.769-774
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• 2006

In this paper the ZnO thin films, which has used spotlight of next generation short wavelength LEDs and semiconductor laser were deposited based on RF magnetron sputtering is described. The temperature at substrate and work pressure, which has implemented in sputtering process of ZnO thin films were settle down at $100^{\circ}C$ and 15 mTorr respectively. The ZnO 5N has used target. The thickness of ZnO thin films was about $1.6{\mu}m$ which was measured by SEM analysis after the sputtering process. Structural properties of ZnO thin films by in-situ and atmosphere annealing were analyzed by XRD. Transformation of grain size and surface roughness were observed by AFM. XPS spectra showed that ZnO thin film had a peak positions corresponding to the $Zn_{2p}$ and the $O_{1s}$. As form above XPS, we confirmed that post-annealing condition changed the atom ratio of Zn/O and microstructure in ZnO thin films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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• pp.15-19
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• 2006

A pulsed laser ablation deposition (PLAD) technique is an excellent method for the fabrication of amorphous carbon (a-C) films, because it can generate highly energetic carbon clusters on a substrate. This paper was focused on the understanding and analysis of the motion of C particles in laser ablation assisted by Ar plasmas. The simulation has carried out under the pressure P=50 mTorr of Ar plasmas. Two-dimensional hybrid model consisting of fluid and Monte-Carlo models was developed and three kinds of the ablated particles which are carbon atom (C), ion ($C^+$) and electron were considered in the calculation of particle method. The motions of energetic $C^+$ and C deposited upon the substrate were investigated and compared. The interactions between the ablated particles and Ar gas plasmas were discussed.

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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• pp.6-11
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• 2001

More than ten kinds of oxide thin films and their heterostructure have been successfully fabricated on SrTiO$_3$(001) substrates by laser molecular beam epitaxy (laser MBE). Measurements of atomic force microscopy (AFM), high-resolution transmission electron microscopy (HRTEM) and X-ray small-angle reflectivity reveal that the surfaces and interfaces are atom-level-smooth. The unit cell layers and the lattice structure are perfect. The electrical and optical properties of BaTiO$_3$-x thin films and BaTiO$_3$/SrTiO$_3$ (BTO/STO) superlattices were examined. The all-perovskite oxide P-N junctions have been successfully fabricated and the better I-V curves were observed.

• 한국표면공학회지
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• 제36권2호
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• pp.148-154
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• 2003

Short ($\tau$=40 $mutextrm{s}$) and high-voltage ($U_{sub}$=2~8 kV) negative substrate bias pulses were used to assist pulsed magnetron sputtering DLC films deposition. Space- and time-resolved probe measurements of the plasma characteristics have been performed. It was shown that in case of high-voltage substrate bias spatial non-uniformity of the magnetron discharge plasma density greatly affected DLC deposition process. By Raman spectroscopy it was found that maximum percentage of s $p^3$-bonded carbon atoms (40 ~ 50%) in the coating was attained at energy $E_{c}$ ~700 eV per deposited carbon atom. Despite rather low diamond-like phase content these coatings are characterized by good adhesion due to ion mixing promoted by high acceleration voltage. Short duration of the bias pulses is also important to prevent electric breakdowns of insulating DLC film during its growth.wth.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1276-1280
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• 2003

Thermal behavior of bromphenols was investigated by direct pyrolysis at high temperature. The thermal degradation products formed by the pyrolysis of mono-bromophenols (o-, m-, and p-) were identified by gas chromatography-mass spectrometry. During the pyrolysis reactions, several kinds of dioxins and furans were produced, and the relative ratio of pyro-products was dependent on the substituted position of bromine in phenolic structure due to the effect of symmetry and steric hindrance. The formation of dioxins can be explained by the phenoxy radical addition and Br atom elimination at an ortho-carbon site on phenolic structure. On the other hand, the formation of furans can be explained by the ortho-ortho carbon coupling of phenoxy radicals at unsubstituted sites to form o, o'-dihydroxydiphenyl intermediate via its keto-tautomer, followed by $H_2O$ elimination. The pyrolysis temperature has also a substantial effect on the dimerized products quantities but little effect on the type of pyro-products. Moreover, the formation mechanism of pyro-products was suggested on the basis of products identified.

• 통합자연과학논문집
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• 제10권3호
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• pp.141-147
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• 2017

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in angiogenesis, which is the formation of new blood vessels from pre-existing vessels. Consequently, blocking of the vascular endothelial growth factor receptor (VEGFR-2) by small molecule inhibitors leads to the inhibition of cancer induced angiogenesis. In this study, we performed a two dimensional quantitative structure activity relationship (2D-QSAR) study of 38 N-Phenyl-N'-{4-(4-quinolyloxy) phenyl} urea derivatives as VEGFR-2 inhibitors based on hologram quantitative structure-activity (HQSAR). The model developed showed reasonable $q^2=0.521$ and $r^2=0.932$ values indicating good predictive ability and reliability. The atomic contribution map analysis of most active compound (compound 7) indicates that hydrogen and oxygen atoms in the side chain of ring A and oxygen atom in side chain of ring C contributes positively to the activity of the compounds. The HQSAR model developed and the atomic contribution map can serve as a guideline in designing new compounds for VEGFR-2 inhibition.

• Carbon letters
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• 제27권
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• pp.1-11
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• 2018

A simple, but effective means of tailoring the physical and chemical properties of carbon materials should be secured. In this sense, chemical doping by incorporating boron or nitrogen into carbon materials has been examined as a powerful tool which provides distinctive advantages over exohedral doping. In this paper, we review recent results pertaining methods by which to introduce boron atoms into the $sp^2$ carbon lattice by means of high-temperature thermal diffusion, the properties induced by boron doping, and promising applications of this type of doping. We envisage that intrinsic boron doping will accelerate both scientific and industrial developments in the area of carbon science and technology in the future.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.104-111
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• 1997

Cluster systems are microcrystals of vanadiumoxided compounds such as Barium, Calcium or Sodium Metavanadates or Sodium Vanadium Bronze which are distributed into dimethyl- or diethylphosphites or microcrystals of vanadium oxides, for instance, vanadium oxide (+3), distributed into the methylphosphonic acid melted. During the interaction of vanadium compounds with the correspondent phosphororganic substances biue viscous liquids are formed. These liquids have paramagnetic properties. According to the UV and IR spectroscopic investigations as well as the results of EPR spectra the substances obtained consist of the nucleus containing 6 to 12 of vanadium atoms and the shell including ligands which are molecules of phosphites or methylphosphonic acid. Here every atom of vanadium interacts with four of phosphorus containing molecules. Sizes of the particles in these systems donot exceed 200 nm. Introduction of cluster systems (0,1 -0,3 % vanadium) into epoxy compositions before the introduction of curing agent - polyethylenepolyamine 6 -8 % leads to the acceleration of composition crosslinking and to the combustion decreasing: 1) Oxygen Index grows to 35: 2)mass losses during combustion decrease to 1-2%, 3) combustion time does not exceed 1 s; 4) the intumescence of material sample is being observed during the burner action as well as the foam coke formation.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.634-641
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• 1995

The metal-carbon σ-bond cluster complexes 1-Mn(CO)5-2-R-1,2-C2B10H10 (R=CH3 Ia, C6H5 Ib) have been prepared in good yields from readily available carboranyl lithium complexes, 1-Li+-2-R-1,2-C2B10H10- (R=CH3, C6H5), by direct reaction with (CO)5MnBr. These manganese metal complexes are rapidly converted to the corresponding manganese metal carbene complexes, 1-[(CO)4Mn=C(OCH3)(CH3)]-2-R-1,2-C2B10H10 (R=CH3 IIIa, C6H5 IIIb), via alkylation with methyllithium followed by O-methylation with CF3SO3CH3. The crystal structure of IIIb was determined by X-ray diffraction. Thus, complex IIIb crystallizes in the orthorhombic space group P212121 with cell parameters a=15.5537(5), b=19.0697(5), c=7.4286(3) Å, V=2203.4(1) Å3, and Z=4. Of the reflections measured a total of 3805 unique reflections with F2>3σ(F2) was used during subsequent structure refinement. Refinement converged to R1=0.053 and R2=0.091. Structural studies showed that the manganese atom had a slightly distorted pseudo-octahedral configuration about the metal center with the carbene and ortho-carborane occupying the equatorial plane cis-orientation to each other.