87 research outputs found
Conformational analysis of some pyridinium phenolates and synthetic precursors based on X-Ray and IR characterisations
7 pagesInternational audienceThis manuscript reports X-Ray and IR characterizations of representative pyridinium phenolates, model compounds for nonlinear optics. These analyses reveal the close dependence existing between molecular structure and the contribution of quinone and zwitterionic limiting forms. The bond length alternation (BLA) values, the well-known parameter correlated to hyperpolarisability β, are also discussed and compared with literature data
Ethyl biodiesels derived from non-edible oils within the biorefinery concept - Pilot scale production & engine emissions
Procedures and operating conditions optimized in laboratory scale for the production of ethyl biodiesels from non-edible vegetable oils (NEVOs) were successfully transferred at pilot scale, with implementation of separation and purification stages. The three NEVOs candidates are Balanites aegyptiaca (BA), Azadirachta indica (AI), and Jatropha curcas (JC), converted into BAEEs, AIEEs and JCEEs respectively via homogeneous catalysis. Quality specifications of the produced biofuels were used to explain pollutant emissions and engine performance observed via a power generator. Under the same conditions, blends of petrodiesel with crude BA or JC oil (50 wt.%) were also investigated. The selected overall methodology “feedstock-conversion-engine” led to the proposal of a sustainable alternative fuel. The candidate NEVO is BA oil to which the proposed alkali route should lead to a low cost biodiesel production process thanks to easy operating conditions, associated with a two-stage procedure (glycerol recycling) and a dry-purification method (rice husk ashes). Glycerol addition should be carried out at ambient temperature to play positively at phenomena occurring in the reacting medium (chemical kinetics, chemical equilibrium, phase equilibrium). Tests on power generator demonstrated that BAEEs led to cleaner combustion than petrodiesel, particularly for the most harmful emissions (light carbonyls and ultrafine particulate matter)
ChemInform Abstract: Stereoselective Synthesis of D,L-Erythrose-, and of D,L-1,4-Dideoxy-4- aminoerythrose Derivatives Bearing a β-Lactam at C-4.
ChemInform Abstract: Methyllithium as a Convenient Deacylating Agent of Alkoxycarbonyl and Benzoyl Protected Secondary Hydrazides. Applications in the Field of Azetidinodiazepines and of Their Photoisomers.
ChemInform Abstract: Stereoisomeric Imidazolo-Pentoses - Synthesis, Chiroptical Properties, and Evaluation as Glycosidase Inhibitors.
ChemInform Abstract: De novo Synthesis of Racemic Altronolactam and Arabinonolactam Azasugars.
ChemInform Abstract: Catalytic One-Pot Osmylation of Cyclohexadienes: Stereochemical and Conformational Studies of the Resulting Polyols.
ChemInform Abstract: STEREOSPECIFIC MOLECULAR DESIGN. SYNTHESIS OF A NEW HETEROTRICYCLIC SYSTEM
ChemInform Abstract: Stereoselective Catalytic Double Osmylation of 1,2-Dihydropyridines leading to Aminoarabinose and to Aminoaltrose Derivatives and to Potential Glycosidase Inhibitors.
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