Tribological Property Study of Xanthate Acetic Ester in Hydrogenated Oil

Xanthate was used as an initial reactant to synthesis two kinds of novel xanthate-containing acetic ester additives (HX and OX), and a four-ball machine was used as tribological tester to appraise their tribological behaviors in hydrogenated oil (10cst). The test results indicated that the as-synthesized additives possess good extreme pressure, antiwear and antifriction properties. The shorter carbon chains acetic ester, the better tribological properties the higher sulfur content. The action mechanism was estimated by analysis of the XPS (X-ray photoelectron spectroscopy) and SEM (scanning electron microscope) results of the worn steel ball surface, and the results illustrated that the protective film containing ferric sulfide and ferric sulfate compound was formed on the worn steel ball surface by xanthate acetic ester , and the protective film has good tribological properties.

The acetylcholine therapy in the treatment of schizophrenia

In the first half of the 20th century, in most European countries, it was thought that cholinesterase and other drugs that counteract acetylcholine should reduce the manifestations of schizophrenia. In 1937, Fiamberti (1894–1970) introduced the transorbital method of lobotomy which established the use of acetylcholine shock treatment for curing the disturbances of schizophrenia. Accepting the idea that the psychic alterations of schizophrenia were caused by a pathological interruption of nerve conduction at a presumably cortical level, Fiamberti thought he could apply this to the clinical field using the properties of acetylcholine, an acetic ester of choline. Here, we examined, in detail, the contribution of Mario Fiamberti to acetylcholine therapy.

Synthesis and Characterization of O-Acetyl-chitosan Acetic Ester

A novel amphipathic chitosan derivative, O-acetyl-chitosan acetic ester (ACHA), was synthesized by the reaction of chitosan with acetic acid in the presence of thionyl chloride. The physicochemical properties of ACHA were characterized by FTIR, 1H NMR, TGA, and XRD. The yield (Y) of ACHA was 79.4%, and the degree of acetylation (DA) of ACHA was 1.04. Compared to CS, ACHA could be dissolved in many organic solvents, deionized water, and aqueous solution. Our results showed that ACHA exhibited a superior antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. These findings indicated that ACHA was preferable for use as antimicrobial agents in wound healing, food preservative, and tissue engineering.

Access to pyridines via DMAP-catalyzed activation of α-chloro acetic ester to react with unsaturated imines

Facile access to trisubstituted pyridines from α-chloro acetic ester and unsaturated imines is achieved.