• catalysis
  • But researchers have wrestled with creating palladium nanoparticles with enough active surface area to make catalysis efficient in fuel cells while preventing particles from clumping together during the chemical processes that convert a fuel source to electricity. (phys.org)
  • The reaction is stepwise and lacks stereospecificity under both palladium and nickel catalysis. (wikipedia.org)
  • 5) Silylated allylic acetates, carbonates and other substituted allyl compounds may form TMM synthons under palladium catalysis. (wikipedia.org)
  • Fagnou's group showed that direct C-H arylation of an indole is possible using palladium catalysis with a copper oxidant. (wikipedia.org)
  • In a supported catalyst system, the significance of using the support are to increase the dispersion of the active phases, to have a better control of the porous structure, to improve mechanical strength, to prevent sintering and to assist catalysis. (wikipedia.org)
  • An iodo-aniline with a tethered alkene was subjected to palladium catalysis. (wikipedia.org)
  • methanol
  • The cathode electrocatalyst is a critical issue in DMFC because the state-of-the-art catalyst, platinum, is very expensive and rare, and its performance is diminished by methanol that crosses over from the anode to the cathode through the Nafion membrane. (utexas.edu)
  • However the alloy catalysts showed similar resistance to dissolution as the displaced catalysts, and the alloyed catalysts were more tolerant to methanol. (utexas.edu)
  • alkene
  • The process typically entails treatment of an alkene with high pressures (between 10 and 100 atmospheres) of carbon monoxide and hydrogen at temperatures between 40 and 200 °C. Transition metal catalysts are required. (wikipedia.org)
  • nanoparticles
  • The scientists report in the online edition of the Journal of the American Chemical Society that they have produced palladium nanoparticles with about 40 percent greater surface area than commercially available palladium particles. (phys.org)
  • Mazumder and Sun created palladium nanoparticles 4.5 nanometers in size. (phys.org)
  • We made high-quality palladium nanoparticles, put them efficiently on a support, then removed them from the stabilizers efficiently without distorting catalyst quality. (phys.org)
  • In this review, we present the most recent advancements about Pd-based catalysts, considering Pd, Pd alloys with different transition metals and non-carbon supported nanoparticles, as possible electrodes in DMFCs. (mdpi.com)
  • exhibit
  • When operated at low temperatures, these catalysts exhibit rapid deactivations on stream due to water inhibition. (catalysisclubphilly.org)
  • SiO 2 -to-Al 2 O 3 ratio (SAR) >1200) as Pd-support, the resulting catalysts exhibit significantly improved activity and on-stream durability at low temperatures, and are able to be regenerated from sulfur poisoning under realistic operating conditions. (catalysisclubphilly.org)
  • complex
  • 3. A process as recited in claim 1, wherein said diluted solution of palladium salt or palladium salt complex comprises a solution of palladium salt or palladium salt complex in a solvent selected from the group consisting of water, an organic solvent, an inorganic acid, an organic acid and mixtures thereof. (google.com)
  • 10. A process as recited in claim 1, wherein said diluted solution of palladium salt or palladium salt complex comprises a solution of palladium salt or palladium salt complex in a solvent comprising a mixture of water, an inorganic acid and a lower aliphatic alcohol. (google.com)
  • 11. A process as recited in any of the claims 1 to 9, wherein the concentration of the palladium salt or palladium salt complex solution is between 0.05 molar and 0.1 molar. (google.com)
  • 17. A process as recited in any of the claims 1, 13 and 14, wherein the amount of alkali which is used is three to six times the amount of said palladium salt or said palladium salt complex. (google.com)
  • nickel
  • Hydrogenation - to treat with hydrogen - is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. (wikipedia.org)
  • Non-precious metal catalysts, especially those based on nickel (such as Raney nickel and Urushibara nickel) have also been developed as economical alternatives, but they are often slower or require higher temperatures. (wikipedia.org)
  • carbon
  • Supported metal catalysts containing 5 wt% Pd on silica, alumina, and activated carbon were evaluated for liquid-phase deoxygenation of stearic (octadecanoic), lauric (dodecanoic), and capric (decanoic) acids under 5 % H-2 at 300 A degrees C and 15 atm. (osti.gov)
  • Palladium on carbon, often referred to as Pd/C, is a form of palladium used as a catalyst. (wikipedia.org)
  • Carbon nanotube supported catalyst is a novel supported catalyst, using carbon nanotubes as the support instead of the conventional alumina or silicon support. (wikipedia.org)
  • Relative research are deposition of palladium and platinum particles on activated carbon, using a poly-acrylate anchor. (wikipedia.org)
  • activity
  • The trade-off is activity (speed of reaction) vs. cost of the catalyst and cost of the apparatus required for use of high pressures. (wikipedia.org)
  • species
  • The intermediate palladium-allyl species was intercepted by the pendant amide nitrogen to generate the prenyl stereocenter in the same reaction. (wikipedia.org)
  • reactive
  • RuPhos was first reported in 2004 as part of a highly reactive catalyst system for the Pd-catalyzed Negishi coupling of organozincs with aryl halides. (wikipedia.org)
  • form
  • One or more kinds of catalysts can be loaded on another material with a high surface area, which serves as the support, to form a supported catalyst as a whole system. (wikipedia.org)
  • metal
  • In the last several years, scientists have discovered that palladium , a metal, is a strong candidate for providing that initial boost that helps fuel cells go. (phys.org)
  • Nonetheless, the increased demand and scarce world reserves of Pt, as well as some technical problems associated with its use, have motivated a wide research focused to design Pd-based catalysts, considering the similar properties between this metal and Pt. (mdpi.com)
  • Precious metal catalysts have been proven to be the most durable for reduction of automotive exhaust emissions. (sae.org)
  • 3-Pentanone is produced by ketonic decarboxylation of propanoic acid using metal oxide catalysts: 2 CH3CH2CO2H → (CH3CH2)2CO + CO2 + H2O in the laboratory, the reaction can be conducted in a tube furnace. (wikipedia.org)
  • frameworks
  • Among other oxide materials, zeolites were also investigated as a potential support for palladium - such as the effects of frameworks and exchange or impregnation methods - but no significant benefits were discovered in the past comparing to conventional alumina-based catalysts. (catalysisclubphilly.org)
  • aromatic
  • Microwave-assisted one-pot dynamic kinetic resolution of aromatic secondary alcohols is successfully conducted by using a recyclable chemoenzymatic catalyst combination. (rsc.org)
  • conventional
  • This revision suggests that it is possible to replace the conventional Pt catalysts by Pd-based materials, although several efforts must be made in order to improve their performance in DMFCs. (mdpi.com)