13 research outputs found
Anionic ring-opening polymerization of <img src='http://www.niscair.res.in/jinfo/smaller.gif' border=0>.<img src='http://www.niscair.res.in/jinfo/small.gif' border=0>-lactide
108-112Poly-.-lactide (PLA) homopolymer has been prepared by
anionic ring-opening polymerization of .-lactide by potassium poly(ethylene glycol-200)ate.
The influenced factors of polymerization such as the amount of the initiator, reaction
period and temperature, concentration of Th monomer, feed way of the reaction mixture
have been investigated. PLA with viscosity-average molecular weight of 5.5Ă—104
has been obtained. The homopolymers are characterized by GPC, DSC, IR and 1HNMR
Analytical pedestrian accident reconstruction using computer simulation. Final report.
Mode of access: Internet.Author corporate affiliation: National Highway Traffic Safety Administration, Vehicle Research and Test Center, East Liberty, OhioSubject code: EMSubject code: EM*ECSubject code: JLMSubject code: WNBFSubject code: WNBJSubject code: WSM*NLSISubject code: XMCSubject code: XM
One-pot selective synthesis of azoxy compounds and imines via the photoredox reaction of nitroaromatic compounds and amines in water
A facile one-pot two-stage photochemical synthesis of aromatic azoxy compounds and imines has been developed by coupling the selective reduction of nitroaromatic compounds with the selective oxidation of amines in an aqueous solution. In the first stage (light illumination, Ar atmosphere), the light excited nitroaromatic molecule abstract H from amine to form ArNO2H and amine radical, which then form nitrosoaromatic, hydroxylamine and imine compounds. Water acts as a green solvent for the dispersion of the reactants and facilitates the formation of nitrosoaromatic and hydroxylamine intermediate compounds. In the second stage (no light, air atmosphere), the condensation of nitrosoaromatic and hydroxylamine compounds yields aromatic azoxy product with the aid of molecular oxygen in air. This photochemical synthesis achieved both high conversion and high product selectivity (>99%) at room temperature
Probing the mechanism of benzaldehyde reduction to chiral hydrobenzoin on the CNT surface under near-UV light irradiation
Metal-free CNTs exhibit high activity (conversion rate 99.6%, 6 h) towards the synthesis of chiral hydrobenzoin from benzaldehyde under near-UV light irradiation (320–400 nm). The CNT structure before and after the reaction, the interaction between the molecule and the CNT surface, the intermediate products, the substitution effect and the influence of light on the reaction were examined using various techniques. A photo-excited conduction electron transfer (PECET) mechanism for the photocatalytic reduction using CNTs has been proposed. This finding provides a green photocatalytic route for the production of hydrobenzoin and highlights a potential photocatalytic application of CNTs