Reagent

About: Reagent is a research topic. Over the lifetime, 60091 publications have been published within this topic receiving 1234928 citations. The topic is also known as: reagens.

Photocatalytic reduction of carbon dioxide over Ag cocatalyst-loaded ALa4Ti4O15 (A = Ca, Sr, and Ba) using water as a reducing reagent.

Abstract: Ag cocatalyst-loaded ALa4Ti4O15 (A = Ca, Sr, and Ba) photocatalysts with 3.79–3.85 eV of band gaps and layered perovskite structures showed activities for CO2 reduction to form CO and HCOOH by bubbling CO2 gas into the aqueous suspension of the photocatalyst powder without any sacrificial reagents. Ag cocatalyst-loaded BaLa4Ti4O15 was the most active photocatalyst. A liquid-phase chemical reduction method was better than impregnation and in situ photodeposition methods for the loading of the Ag cocatalyst. The Ag cocatalyst prepared by the liquid-phase chemical reduction method was loaded as fine particles with the size smaller than 10 nm on the edge of the BaLa4Ti4O15 photocatalyst powder with a plate shape during the CO2 reduction. CO was the main reduction product rather than H2 even in an aqueous medium on the optimized Ag/BaLa4Ti4O15 photocatalyst. Evolution of O2 in a stoichiometric ratio (H2+CO:O2 = 2:1 in a molar ratio) indicated that water was consumed as a reducing reagent (an electron donor) fo...

Preparation and use of tetra-n-butylammonium per-ruthenate (TBAP reagent) and tetra-n-propylammonium per-ruthenate (TPAP reagent) as new catalytic oxidants for alcohols

Abstract: Tetra-n-butylammonium per-ruthenate (Bun4N)(RuO4) and tetra-n-propylammonium per-ruthenate (Prn4N)(RuO4), with N-methylmorpholine N-oxide, function as mild catalytic oxidants for the high yield conversion of alcohols to aldehydes and ketones and are competitive with more conventional reagents.

Nitric Acid Purification of Single-Walled Carbon Nanotubes

Abstract: We report a systematic evaluation of the use of refluxing nitric acid as a purification treatment for electric arc-produced single-walled carbon nanotubes (SWNTs), by using a combination of thermogravimetric analysis (TGA) and near-infrared (NIR) spectroscopy. Nitric acid is the standard reagent for purification of SWNTs and has traditionally constituted the first step in many different purification schemes. It has been suggested that nitric acid removes the transition metal catalyst that is used in the production of the SWNTs together with amorphous carbon. Under all conditions, we find that nitric acid destroys SWNTs to produce amorphous carbon while reducing the amount of transition metal catalyst remaining in the sample. Thus, nitric acid is suitable for removing the catalyst from SWNT samples, but only at the expense of a significant destruction of the SWNTs.

Chemical Basis of the Sulfo-phospho-vanillin Reaction for Estimating Total Serum Lipids

Abstract: Results with the "sulfo-phospho-vanillin" reaction, much used for determining total serum lipids, have been favorably compared with those for the gravimetric method. We investigated the basic chemistry of the reaction and determined the reactivity of this single reagent with various lipids. Our results suggest that: ( a ) The reaction requires a carbon-carbon double bond. ( b ) Concentrated sulfuric acid reacts with unsaturated lipids in the initial step to form a carbonium ion. ( c ) Phosphoric acid reacts with vanillin to produce a phosphate ester, with a resulting increase in the reactivity of the carbonyl group. ( d ) The carbonium ion reacts with the carbonyl group of phosphovanillin to form a colored compound, which is stabilized by resonance. ( e ) Unsaturated compounds with more than one double bond react, but reaction may vary with steric hindrance. ( f ) The method is reasonably precise, but its accuracy depends primarily on the reference standard used.