• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2947-2952
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• 2013

Three coordination polymers, [$ML_2(H_2O)_2$] (M = Co (1), Ni (2), Mn (3)), were prepared from metal acetates ($M(CH_3COO)_2{\cdot}4H_2O$) and 3-pyridinepropionic acid ($HL=(3-py)-CH_2CH_2COOH$) by solvent-layer methods. By contrast, a discrete molecular compound, trans-[$Pd(HL)_2Cl_2$] (4), was synthesized by replacing benzonitrile (PhCN) ligands in trans-[$Pd(PhCN)_2Cl_2$] with HL under microwave-heating conditions. Compounds 1-3 have a 2D framework, and compound 4 contains a square-planar Pd metal.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.05a
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• pp.173-179
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• 2005

본 연구에서는 Nickel-Metal Induced Lateral crystallization(Ni-MILC)에 depart에 따른 영향을 관찰함에 있어 Nickel에 Palladium Metal을 인접시켜(Pd assisted Ni-MILC) 그 결정화 속도를 향상시키는 방법을 제안하였다. a-Si에 Phosphorous가 doping 되어 있는 경우 Ni-MILC의 성장은 intrinsic에 비해 2.5배 감소되는 반면, Boron을 doping한 경우 Ni-MILC의 성장은 intrinsic의 경우보다 5배 이상의 성장을 보이게 되는데, well type의 Pd을 인접시킨 경우 Pd에 의해 유도된 tensile stress가 각 doping에 따른 성장 속도를 더욱 증대시키는 것을 확인할 수 있었으며, 이와 같은 현상을 MILC mechanism으로 설명하였다. 이는 Ni-MILC를 이용하여 다결정 실리콘 TFT 제작 시 결정화 속도로 인하여 문제가 되었던 N-type에서의 적용이 가능함과 동시에 contact MILC 등의 방법에도 이용가능성을 의미한다.

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2434-2440
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• 2008

The effect of sodium (Na) promotion was studied in the biphenol (BP) hydrogenation using various Pd/C catalysts. Different amounts of sodium metal were used for promotion with Pd/C and their effects on BP hydrogenation were observed. The promotion order was changed to compare the effect of the position of the promoter in relation to the palladium (Pd) metal on the catalytic activity and yield of the final product, bicyclohexyl-4,4'-diol (BHD). Pd/C catalysts prepared from different methods were also sodium-promoted and the changes of the reaction pathway according to the type of promoted Pd/C catalyst were compared.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.52-62
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• 2013

The interaction of titanium (IV), yttrium (III), zirconium (IV), palladium (II) and cerium (IV) with deprotonated enrofloxacin leads to the formation of the neutral or cationic mononuclear complexes. The isolated solid complexes have been characterized with physicochemical and spectroscopic techniques and thermogravimeteric analyses. The spectroscopic data indicate that the enrofloxacin ligand is on the deprotonated mode acting as bidentate ligand coordinated to the metal ions through the ketone oxygen and a carboxylato oxygen and the metal ions completed the coordination number with water molecules. The thermal decomposition mechanisms proposed for enrofloxacin and their metal complexes were discussed. The activation energies, $E^*$, enthalpies, ${\Delta}H^*$, entropies, ${\Delta}S^*$ and Gibbs free energies, ${\Delta}G^*$, of the thermal decomposition reactions have been derived from thermogravimetric (TG) and differential thermogravimetric (DTG) curves, using Coats-Redfern (CR) and Horowitz-Metzeger (HM) methods. The antimicrobial activity has been evaluated against six different microorganisms.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.361-364
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• 2013

A modified synthetic approach to the synthesis of heterocyclic food mutagens, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP) and 2-amino-1,6-dimethylimidazo[4,5-b]pyridine (DMIP) is reported. This route highlights an optimized palladium catalysed Buchwald cross-coupling of 2-halo-1-methyl-imidazo[4,5-b]pyridine with benzophenoneimine followed by acidic hydrolysis to yield compound 7. Using finely tailored conditions, Suzuki cross-coupling reactions with highly efficient catalytic systems were performed as the final step on 8 to introduce the aryl group and methyl group on the heterocyclic core.

• Journal of Hydrogen and New Energy
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• v.11 no.4
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• pp.179-188
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• 2000

The anodic reaction of hydrogen/oxygen gas mixture at platinum or palladium electrode interfacing with a solid polymer electrolyte was investigated using AC impedance method. The impedance spectrum of the electrode reactions of the mixture depends on the gas composition, electrode roughness, the mode of electrochemical operation and the cell potential. For electrolysis mode of operation, the spectrum taken for the reaction on a rough platinum electrode for the gas mixture revealed clearly that the local anodic reduction of oxygen gas takes place concurrently with the anodic oxidation of hydrogen gas.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.6
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• pp.558-562
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• 2006

We have synthesized a new p-type polymer, poly(9,9'-n-dioctylfluorene-alt-phenoxazine) (PFPO), via the palladium catalyzed coupling reaction. The number average molecular weight ($M_n$) of PFPO was found to be 23,000. PFPO dissolves in common organic solvents such as chloroform and toluene. The UV-visible absorption maximum of the PFPO thin film is clearly blue-shifted with respect to that of F8T2, poly-(9,9'-n-dioctylfluorene-alt-bithiophene). The introduction of the phenoxazine moiety into the polymer system results in better field-effect transistor (FET) performance than that of F8T2. A solution processed PFPO TFT device with a top contact geometry was found to exhibit a hole mobility of $2.7{\times}10^{-4}cm^2/Vs$ and a low threshold voltage of -2 V with high on/off ratio(${\sim}10^4$).

• The Korean Journal of Ceramics
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• v.2 no.2
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• pp.83-88
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• 1996

Long term stability, sensitization in air, and gas sensing behaviors of tin oxide films were investigated with doping of antimony and palladium. The tin oxide films were prepared on a Corning glass by reactive rf sputtering method and tested for detection of hydrogen gas. Sb-doping improved a long-term stability in the base resistance of $SnO_2$ film sensor. A small amount of Pd doping caused the optimum sensor operating temperature to reduce and also enhanced the gas sensitivity, compared with the undoped $SnO_2$ film. Gas sensitivity depended largely on the film thickness. The important sensitization reactions for sensor operating were $(O_{2ads})+e^-\;{\rightarrow}\;2(O_{ads})^-$ on the surface of $SnO_2$ film at elevated temperature in air and a followed reaction of hydrogen atoms with $(O_{ads})^-$ ions.

• Journal of Sensor Science and Technology
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• v.29 no.6
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• pp.399-406
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• 2020

Pd nanogap hydrogen sensors were developed using an elastomeric substrate and operated through an on-off mechanism. A 10 nm thick Pd thin film was formed on a polydimethylsiloxane (PDMS) substrate, and 50% of the physical strain was applied in the longitudinal direction to fabricated uniform nanogaps. The initial concentration of the hydrogen gas for the PDMS/Pd films was controlled, and subsequently, the on-off switching response was measured. We found that the average nanogap was less than 50 nm, and the Pd nanogap hydrogen sensors operated over a wide range of temperatures. In particular, the sensors work properly even at a very low temperature of -40℃ with a fast response time of 2 s. In addition, we have investigated the relative humidity and annealing effects.

• Journal of the Korean Magnetic Resonance Society
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• v.8 no.1
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• pp.62-69
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• 2004

Bicyclolactones obtained from the Diels-Alder cycloaddition of 3,5-dibromo-2-pyrone can undergo various palladium catalyzed cross coupling reactions to afford aryl bicyclolactones. The resulting coupled products can be readily converted into various 3-OH cyclohexenes via lactone ring openings, while those bearing dienyl units underwent highly diastereoselective Diels-Alder cycloadditions with selected dienophiles to funish multiply functionalized polycarbocycles. Bromo-bicyclic diene furnished two different diastereomers endo-form (62%) and exo-form (38%) upon cycloadditions with N-Et maleimide (NEM), and their stereochemistries were identified with NMR.