A new generation of radio telescopes is achieving unprecedented levels of sensitivity and resolution, as well as increased agility and field-of-view, by employing highperformance digital signal processing hardware to phase and correlate large numbers of antennas. The computational demands of these imaging systems scale in proportion to BMN2, where B is the signal bandwidth, M is the number of i...

hantzsch 1,4-dihydropyridines are oxidized to the corresponding pyridine derivatives using oxygen or air and a mixture of the manganese and cobalt salts of parninobenzoic acid supported on silica gel as the catalysts. reactions are clean and the catalysts can be recovered easily and reused repeatedly.

two-component reaction of 2-aminobenzophenones with acetylenic esters in the presence of γ-al2o3 and cu/zno as suitable heterogeneous catalysts has been studied. nano γ-al2o3 and cu/zno showed high activities when used as surface catalysts for the synthesis of quinoline derivatives. after completion of the reaction, the catalyst was recovered and reused several times under the same reaction con...

Accelerated deactivation of Co/Al2O3 catalysts in Fischer-Tropsch synthesis and the effect of Re and Ru as the catalytic promoters are reported. 15wt% Co/Al2O3 catalyst and 1wt% Ru and 1.4wt% Re  promoted cobalt catalysts have been formulated and extensively characterized. The deactivation of the unpromoted cobalt catalyst and those promoted with ...

Initiation rates for Grubbs and Grubbs-Hoveyda second generation pre-catalysts have been measured accurately in a range of solvents. Solvatochromic fitting reveals different dependencies on key solvent parameters for the two pre-catalysts, consistent with different mechanisms by which the Grubbs and Grubbs-Hoveyda pre-catalysts initiate.

In this review, we provide an overview of recent progress in nanocarbons with different dimensions as noble-metal-free co-catalysts for photocatalysts. We put emphasis on the interface engineering between nanocarbon co-catalysts and various semiconductor photocatalysts and the novel properties generating of nanocarbon co-catalysts, also including the synthesis and application of nanocarbon-base...

A straightforward synthesis utilizing the ring-opening metathesis polymerization (ROMP) reaction is described for acid-triggered N,O-chelating ruthenium-based pre-catalysts bearing one or two 8-quinolinolate ligands. The innovative pre-catalysts were tested regarding their behavior in ROMP and especially for their use in the synthesis of poly(dicyclopentadiene) (pDCPD). Bearing either the commo...

There remains considerable debate over the active form of gold under operating conditions of a recently validated gold catalyst for acetylene hydrochlorination. We have performed an in situ x-ray absorption fine structure study of gold/carbon (Au/C) catalysts under acetylene hydrochlorination reaction conditions and show that highly active catalysts comprise single-site cationic Au entities who...

3.1. Overview 2807 3.2. Chiral Aluminum(III) Complexes as a Catalyst 2808 3.2.1. Aluminum(III)-Salen-Based Catalysts 2808 3.2.2. Aluminum(III)-Binaphthol-Based Catalysts 2810 3.3. Chiral Titanium(IV) Complexes as a Catalyst 2814 3.3.1. Titanium(IV)-Peptide-Based Catalysts 2814 3.3.2. Titanium(IV)-Diol-Based Catalysts 2817 3.4. Chiral Zirconium(IV) Complexes as a Catalyst 2818 3.4.1. The Catalyt...

We report a systematic comparison of the steric properties of different stereoselective olefin polymerization catalysts using the percentage of buried volume, %V(Bur), as a molecular descriptor. For the first time, isoselective and syndioselective group 4 metallocenes are compared with group 4 isoselective phenoxy-amine and group 4 syndioselective phenoxy-imine catalysts using the same molecula...