To investigate factors regulating ammonia (NH3) production by isolated defined proximal tubule segments, we examined the rates of total NH3 (NH3 + NH+4) production by individual proximal tubule segments perfused in vitro under a variety of perfusion conditions. Segments consisting of late convoluted and early straight portions of superficial proximal tubules were incubated at 37 degrees C in Kr...

Ammonia adsorption on single-walled carbon nanotubes (SWNTs) was studied by means of infrared spectroscopy at both cryogenic (approximately 94 K) and room (approximately 300 K) temperatures. At 94 K, vacuum-annealed SWNTs showed no detectable ammonia uptake. However, the ammonia adsorption was found to be sensitive to the functionalities and defects on the nanotube surfaces. NH3 adsorption was ...

The effect of short-term ammonia starvation on Nitrosospira briensis was investigated. The ammonia-oxidizing activity was determined in a concentrated cell suspension with a NOx biosensor. The apparent half-saturation constant [Km(app)] value of the NH3 oxidation of N. briensis was 3 microM NH3 for cultures grown both in continuous and batch cultures as determined by a NOx biosensor. Cells grow...

We study the ammonia addition reactions of H2SO4·NH3 molecular clusters containing up to four ammonia and two sulfuric acid molecules using the ab initio method RI-MP2 (Resolution of Identity 2nd order MøllerPlesset perturbation theory). Together with results from previous studies, we use the computed values to estimate an upper limit for the ammonia content of small atmospheric clusters, witho...

Tellurium thin films were studied for use as ammonia gas sensors operable at room temperature. The films showed a reversible increase in resistance when exposed to ammonia and the response was found to be linear in the range of 0-100 ppm. The interaction of ammonia with tellurium film was investigated using Raman, X-ray photoelectron and impedance spectroscopy techniques. The results of Raman a...

1. Though nitrogen exhibits +5 oxidation state, it does not form pentahalide. Give reason. Ans: Nitrogen valence electronic configuration nsnp due to absence empty dorbitals, it can not extend its valence to 5 2. PH3 has lower boiling point than NH3. Why? Ans: Unlike NH3, PH3 molecules are not associated through hydrogen bonding in liquid state. That is why the boiling point of PH3 is lower tha...

The present study investigates the decomposition of ammonia (NH3) over Ni and Ru catalysts using a kinetic model based on a reaction mechanism consisting of kinetically important elementary steps. Experimental results obtained over a wide range of reaction conditions were reproduced by the model. Recombinative N2 desorption was the rate-limiting step on the Ru catalyst; whereas, the overall rat...

Renal ammonia metabolism is a fundamental element of acid-base homeostasis, comprising a major component of both basal and physiologically altered renal net acid excretion. Over the past several years, a fundamental change in our understanding of the mechanisms of renal epithelial cell ammonia transport has occurred, replacing the previous model which was based upon diffusion equilibrium for NH...

The synthesis, crystal structure and dehydrogenation performances of two new H-enriched compounds, Mg(BH4)2(NH3BH3)2 and Mg(BH4)2·(NH3)2(NH3BH3), are reported. Due to the introduction of ammonia ligands, the Mg(BH4)2·(NH3)2(NH3BH3) exhibits dramatically improved dehydrogenation properties over its parent compound.

We have performed density functional theory investigations on the adsorption properties of ammonia molecule on the undoped and N-doped TiO2 anatase nanoparticles. We have geometrically optimized the constructed undoped and N-doped nanoparticles in order to fully understand the adsorption behaviors of ammonia molecule. For TiO2 anatase nanoparticles, the binding site is preferentially located on...