The inhibition effects and mechanisms of chlorinated methane and acetylene on methanogenesis in the anaerobic digestion process of the biodegradable wastes were investigated. It was found that both chloroform and acetylene could effectively inhibit methanogens while the biodegradability of the wastes was not affected. Acetylene inhibited the activity of methanogens, while chloroform inhibited m...

Acetylene cyclotrimerization catalyzed by palladium has been shown to proceed via the initial rapid formation of a C 4 H 4 species. This can either react with adsorbed acetylene to form benzene or alternatively, as has been recently suggested, it can dimerize forming cyclooctatetraene which decomposes to yield benzene. Trimerization is sufficiently fast that reaction is desorption rather than s...

We demonstrate selective functionalization of independently addressed microelectrodes by electrochemical activation and deactivation of a coupling catalyst. 1,2,3-Triazole formation between terminal acetylenes and organic azides is efficiently catalyzed by copper(I) complexes (a Sharpless "click" reaction), while the oxidized copper(II) complexes are inactive. By electrochemically activating or...

In interior Alaskan boreal forests two species of alder, Alnus tenuifolia and Alnus crispa, represent keystone species in floodplain and upland landscapes, respectively, due to the ability of these plants to form symbiotic associations with the nitrogen-fixing actinomycete, Frankia. It is believed that as much as 70% of the nitrogen (N) accumulated during the 200-y successional development of t...

Acetylene fermentation is a rare metabolism that was previously reported as being unique to Pelobacter acetylenicus Here, we report the genome sequence of Pelobacter sp. strain SFB93, an acetylene-fermenting bacterium isolated from sediments collected in San Francisco Bay, CA.

The potential to stimulate an indigenous microbial community to reduce a mixture of U(VI) and Tc(VII) in the presence of high (120 mM) initial NO3- co-contamination was evaluated in a shallow unconfined aquifer using a series of single-well, push-pull tests. In the absence of added electron donor, NO3-, Tc(VII), and U(VI) reduction was not detectable. However, in the presence of added ethanol, ...

Nitrogen fixation (acetylene reduction) rates of nodules on intact field-grown soybean (Glycine max) subjected to altered oxygen concentration (0.06-0.4 cubic millimeter per cubic millimeter) returned to initial rates during an 8-hour transitory period. Hydroponically grown soybean plants also displayed a transitory (1-4 hours) response to changes in the rhizosphere oxygen concentration after w...

The growth mechanism of hydrocarbons in ionizing environments, such as the interstellar medium (ISM), and some combustion conditions remains incompletely understood. Ab initio molecular dynamics (AIMD) simulations and molecular beam vacuum-UV (VUV) photoionization mass spectrometry experiments were performed to understand the ion-molecule growth mechanism of small acetylene clusters (up to hexa...

395 ABSTRACT Since the legume responses to environmental factors may be different in grass mixtures than in pure stands, a pot experiment was conducted to evaluate the effects of plant top and root competition on the growth and N fixation of Desmodium intortum, cv. ‘Greenleaf’ grown in association with Setaria anceps, cv. 'Nandi' The plants were grown in deep, narrow pots which provided for ± t...

Nanosized CuO-CeO2, CuO-Fe2O3, CuO-CeO2-Al2O3 and CuO-Fe2O3-CeO2-Al2O3 were prepared by co-precipitation and wet impregnation techniques and were used for Catalytic decomposition of acetylene to produce carbon nanotubes (CNTs). Weight gain technique was used to follow up the catalytic reactions. The results revealed that catalyst chemical composition, catalytic temperature, acetylene flow rate ...