Hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) was studied by using mono- and bidentate p-cymene ruthenium(ii) N-heterocyclic carbene (NHC) complexes as catalyst precursors. In water, all complexes were found to be reduced in situ to form ruthenium nanoparticles (RuNPs) with a high hydrogenation activity. In organic solvents, complexes with monodentate NHC ligands also formed nan...

A novel method has been developed for preparing supported cubic platinum nanoparticles. Carbon monoxide and hydrogen are used to reduce platinum precursors present at a solid-gas interface and to control the shape of the growing Pt nanoparticles. By avoiding the use of any organic agents in the synthesis, cubic Pt particles free of hydrocarbons are formed, thereby avoiding possible contaminatio...

Robust catechol-functionalized porous organic polymers (POPs) with tunable porosities (560−1050 m/g) and degrees of functionalization were synthesized using a cobaltcatalyzed acetylene trimerization (CCAT) strategy. Post-synthesis metalation can be readily carried out with a wide range of metal precursors (Cu, Mg, and Mn salts and complexes), resulting in metalated POPs with enhanced heat of hy...

A new class of nitrogen-containing endoperoxides were synthesised by a photochemical [4 + 2]-cycloaddition between a diene and singlet oxygen. The endoperoxides were dihydroxylated and protected to provide a series of endoperoxide building blocks for organic synthesis, with potential use as precursors for the synthesis of branched azasugars. Preliminary exploration of the chemistry of these bui...

Strontium titanate (SrTiO(3)) nanoparticles with well defined cubic shape and sub-10 nm size that are highly dispersible in non-polar organic solvents were successfully synthesized by hydrothermal (HT) processing. Water-soluble titanium complexes and strontium hydroxide were employed as precursors. When the HT process was carried out without oleic acid, the SrTiO(3) particles obtained were rela...

Biotilters are recognized by an increasing number of state air quality regulatory agencies as ”best available control technology” (BACT) for treatment of volatile organic compounds (VOCs) and odor. This has been the case for two cocomposting facilities permitted by Bedminster Bioconversion Corporation in Cobb County, Georgia, and Marlborough. Massachusetts. Both areas are in ozone non-attainmen...

What are they? The gibberellins make up a family of small organic compounds derived from a common 20-carbon precursor. They regulate growth and development in plants and their chemical structure superficially resembles that of steroid hormones. So far, more than 100 gibberellins have been identified. Fortunately, any one plant species produces only a few of the known gibberellins. Furthermore, ...

The highly effective self-assembly process between 2,4,6-tris(isopropyl)phenylphosphine or mesitylphosphine, formaldehyde and 1,4-bis(alpha-(4'-aminophenyl)isopropyl)benzene results in the formation of a novel type of heterocyclophane which is able to encapsulate organic molecules as well as being a potential ligand for transition metals inside the intramolecular cavity. Compounds of this type ...

A series of experiments has been conducted in the Caltech indoor smog chamber facility to investigate the water uptake properties of aerosol formed by oxidation of various organic precursors. Secondary organic aerosol (SOA) from simple and substituted cycloalkenes (C5-C8) is produced in dark ozonolysis experiments in a dry chamber (RH∼5%). Biogenic SOA from monoterpenes, sesquiterpenes, and oxy...

conclusions scc, lgdn, and hgdn are common associated findings and precursors of hcc in livers infected with hepatitis b. a strict follow-up and a precise and thorough sampling of livers with scc and any abnormal dysplastic nodules (dns), especially those larger than 1 cm, are highly recommended because these dns are highly associated with malignancy. results among all explanted cirrhotic liver...