• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3745-3748
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• 2010

Pd(II) p-tolylamide Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)(NH($C_6H_4Me$-p)) (1) was metathetically prepared by the reaction of Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)Cl with NaNH($C_6H_4Me$-p). Treatment of 1 with carbon dioxide affords the palladium(II) carbamate Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)(OC(O)NH($C_6H_4Me$-p)) (2), quantitatively. Complex 2 reacts with HX (X = Cl, OTf) to give Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)X, $NH_2$(p-Tol) and $CO_2$. Reaction of the palladium(II) carbamate with MeI produced Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)I along with generation of methyl N-tolylcarbamate MeOC(O)NH($C_6H_4Me$-p), exclusively.

• Korean Journal of Crystallography
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• v.12 no.1
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• pp.10-13
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• 2001

Compound PdCl₂(PhCN)₂(1) reacted with tert-butylamine(t-BuNH₂) to give trans-[PdCl₂(t-BuNH₂)₂] (2) Compound 2 was characterized by spectroscopy (¹H-NMR, /sup 13/C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for f2: monoclinic space group p2₁/c, a=6.298(1)Å, b=20.740(2)Å, c=10.731(1)Å, β=92.58(1)°, Z=4, R(wR₂)=0.0207(0.0543).

• Membrane Journal
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• v.34 no.1
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• pp.50-57
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• 2024

In this experiment, Pd-Ag-Cu membrane was manufactured using electroless plating on an α-Al₂O₃ support. Pd, Ag and Cu were each coated on the surface of the support through electroless plating and heat treatment was performed for 18 h at 500℃ in H₂ in the middle of electroless plating to form Pd alloy. The surface of the Pd-Ag-Cu membrane was observed through Scanning Electron Microscopy (SEM), and the thickness of the Pd membrane was measured to be 7.82 ㎛ and the thickness of the Pd-Ag-Cu membrane was measured to be 3.54 ㎛. Energy dispersive X-ray spectroscopy and X-ray diffraction analysis confirmed the formation of a Pd-Ag-Cu alloy with a composition of Pd-78wt%, Ag-8.81wt% and Cu-13.19wt%. The gas permeation experiment was conducted under the conditions of 350~450℃ and 1~4 bar in H₂ single gas and H₂/N₂ mixed gas. The maximum H₂ flux of the hydrogen separation membrane measured in H₂ single gas is 74.16 ml/cm²·min at 450℃ and 4 bar for the Pd membrane and 113.64 ml/cm²·min at 450℃ and 4 bar for the Pd-Ag-Cu membrane. In the case of the separation factor measured in H₂/N₂ mixed gas, separation factors of 2437 and 11032 were measured at 450℃ and 4 bar.

• Analytical Science and Technology
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• v.9 no.3
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• pp.221-234
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• 1996

Basic studies for the effective extraction of dibenzylammonium dibenzyldithiocarbamate(DBADBDC) complexes of Ag(I), Pd(II), Au(III) and Pt(IV) into chloroform have been conducted. The effects of pH on the extraction of ligand itself and metal cemplexes showed that DBADBDC itself was uniformly extracted in the pH range of 2~9 and metal complexes were effectively extracted at the pH range as follows. That is, Ag(I) : in an acidic aqua medium, Pd(II) : > 4, Au(III) : wide range, and Pt(IV) : > 3. The distribution ratio and extractabilities were obtained from the partition and extraction equilibria of metal-DBDC complexes between aqueous solution and chloroform. Ag(I) : log D=4.226 : E(%)=99.9% in the aqueous solution of pH 0, Pd(II) : log D=1.804 : E(%)=98.5% at pH 4~7, Au(III) : log D=3.755 : E(%)=99.9% at pH 2~10, and Pt(IV) : log D=0.165 : E(%)=57.2% at pH 8.0. And also mole ratio of metal ion to ligand in complexes were determined by mole ratio method : 1 : 1 for Ag(I) and 1 : 2 for Pd(II), Au(III) and Pt(IV). $Cl^-$ was included as a coordination species in complexes of Au(III) and Pt(IV). Besides, extraction mechanisms of compleses sere examined in the presence of chloride ion in an aquous solution, and extraction reactions and estraction constants could be proposed and calculated, respectively.

• KSBB Journal
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• v.17 no.3
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• pp.255-260
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• 2002

1,3-Propanediol as a bifunctional organic compound could be used in polymerization reactions producing polyesters and polyurethanes. Byproduct containing high concentration of glycerol from fat industry was used to produce 1,3-propanediol in lower production cost as well as waste treatment. In this study, various attempts were made to increase 1,3-propanediol production under different conditions using Klebsiella pneumoniae ATCC 15380. The conversion yield and byproduct formation were influenced significantly by the fermentation pH and temperature. The optimal glycerol and nitrogen concentration for 1,3-propanediol production were found to be 25 a/L and 1%(w/v), respectively. The formation of 1,3-propanediol was optimal at pH 6.0 and temperature $35^{\circ}C$. 1,3-Propanediol production from byproduct from 2.5% glycerol was lower than that of 2.5% commercial glycerol and amounted only to 9.84 a/L from byproduct, while to 12.13 a/L from commercial glycerol.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.539-545
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• 2018

4-Hydroxy-2-(4-hydroxyphenethyl)isoindoline-1,3-dione (PD1) is a synthetic phthalimide derivative of a marine compound. PD1 has peroxisome proliferator-activated receptor (PPAR) ${\gamma}$ agonistic and anti-inflammatory effects. This study aimed to investigate the effect of PD1 on allergic asthma using rat basophilic leukemia (RBL)-2H3 mast cells and an ovalbumin (OVA)-induced asthma mouse model. In vitro, PD1 suppressed ${\beta}$-hexosaminidase activity in RBL-2H3 cells. In the OVA-induced allergic asthma mouse model, increased inflammatory cells and elevated Th2 and Th1 cytokine levels were observed in bronchoalveolar lavage fluid (BALF) and lung tissue. PD1 administration decreased the numbers of inflammatory cells, especially eosinophils, and reduced the mRNA and protein levels of the Th2 cytokines including interleukin (IL)-4 and IL-13, in BALF and lung tissue. The severity of inflammation and mucin secretion in the lungs of PD1-treated mice was also less. These findings indicate that PD1 could be a potential compound for anti-allergic therapy.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.376-381
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• 2018

The purpose of this study is to investigate and optimize an effectiveness process for the recovery of Pd from the spent Pd/C catalyst by the process of hydrogenation of maleic anhydride over Pd/C. Pd solution recovered from Pd/C catalyst was used to prepare Pd/C catalysts. Their characteristics were compared to those of Pd/C catalyst prepared by using a reagent grade precursor solution. Pd in the spent catalyst was leached by the modified process with dry and wet methods to obtain the high recovery ratio of Pd. The burn-out of carbon in the spent Pd/C catalyst was carried out in the rage of $600-900^{\circ}C$. Pd content of carbonized catalyst was confirmed by XRF and ICP. Pd was extracted from carbonized spent catalysts with acid solutions of 1,2 and 4 M HCl at a leaching temperature of $90^{\circ}C$ for 2 h. The high recovery ratio of Pd was shown as 92.4% that leached in 4 M HCl. Also Pd/C catalysts were prepared by using the leached solution and the reagent grade of $H_2PdCl_4$ as a precursor solution and the characteristics were analyzed by XRD, CO-chemisorption and FE-TEM. As a result, the dispersion of the catalyst prepared by using the leached solution was 34.6%, which was found to be equal to or more than that of the Pd/C catalyst prepared by the reagent grade precursor solution.

• Clean Technology
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• v.19 no.1
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• pp.65-72
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• 2013

In this study, we investigated the activity of Pd and Cu co-incorporated on mesoporous silica support such as MCM-41 and SBA-15 for catalytic nitrate reduction in water. In pure hydrogen flow, nitrate concentration was gradually decreased with the reaction time, but nitrogen selectivity was too low due to very high pH of reaction medium after the reaction. In order to acquire high nitrogen selectivity, we utilized carbon dioxide as a pH buffer, which resulted in higher nitrogen selectivity (about 40%). For the above reaction conditions, Pd-Cu/MCM-41 showed better performance than Pd-Cu/SBA-15. The physicochemical properties of both catalysts were investigated to figure out the relationship between the characteristics of the catalysts and the catalytic activity on the catalytic nitrate reduction by $N_2$ adsoprtion-desorption, X-ray diffraction (XRD), $H_2$-temperature programmed reduction, X-ray photoelectron spectroscopy (XPS) techniques.

• Membrane Journal
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• v.32 no.6
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• pp.456-464
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• 2022

Hydrogen permeation performance was analyzed by manufacturing Pd and Pd-Cu membranes through electroless plating. As a support for the Pd and Pd-Cu membranes, α-Al₂O₃ ceramic hollow fiber were used. Pd-Cu membrane was manufactured through sequential electroless plating, and then annealing was performed at 500°C, for 18 h in a hydrogen atmosphere to make Pd and Cu alloy. After annealing, the Pd-Cu membrane confirmed that the alloy was formed through EDS (Energy Dispersive X-ray Spectroscopy) and XRD (X-ray Diffraction) analysis. In addition, the thickness of the Pd and Pd-Cu plating layers were measured to be about 3.21 and 3.72 µm, respectively, through SEM (Scanning Electron Microscope) analysis. Hydrogen permeation performance was tested for hydrogen permeation in the range of 350~450°C and 1~4 bar in hydrogen single gas and mixed gas (H₂, N₂). In a single hydrogen gas, Pd and Pd-Cu membranes have flux of up to 54.42 and 67.17 ml/cm²⋅ min at 450 °C and 4 bar. In the mixed gas, it was confirmed that the separation factors of 1308 and 453 were obtained under the conditions of 450 °C and 4 bar.

• Journal of Magnetics
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• v.17 no.2
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• pp.86-95
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• 2012

This study investigated the effects of adding a third alloying element, Ni, to create $Fe_{70-x}Pd_{30}Ni_x$ (x = 2, 4, 6, 8 at.% Ni) ferromagnetic shape memory alloys (FSMAs). The Ni replaced a portion of the Fe. The $Fe_{70-x}Pd_{30}Ni_x$ alloys were homogenized through hot and cold forging to gain a ~38% reduction in thickness, next they were solution-treated (ST) with annealing recrystallization at $1100^{\circ}C$ for 8 h and quenched in ice brine, and then aged at $500^{\circ}C$ for 100 h. Investigation of the microstructures and magnetostriction indicated that the greater Ni amount in the $Fe_{70-x}Pd_{30}Ni_x$ alloys reduced saturation magnetostriction at room temperature (RT). It was also observed that it was more difficult to generate annealed recrystallization. However, with greater Ni addition into the $Fe_{70-x}Pd_{30}Ni_x$ (x = 6, 8 at.% Ni) alloys, the $L1_0+L1_m$ twin phase decomposition into stoichiometric $L1_0+L1_m+{\alpha}_{bct}$ structures was suppressed after the $500^{\circ}C$/100 h aging treatment. The result was that the $Fe_{70-x}Pd_{30}Ni_x$ (x = 6, 8 at.% Ni) alloys maintained a high magnetostriction and magnetostrictive susceptibility (${\Delta}{\lambda}{_\parallel}{^s}/{\Delta}H$) after the alloys were aged at $500^{\circ}C$ for 100 h. This magnetic property of the $Fe_{70-x}Pd_{30}Ni_x$ (x = 6, 8 at.% Ni) alloys make it suitable for application in a high temperature (T > $500^{\circ}C$) and high frequency environments.