Local oxygen

This justifies all the work undertaken to arrive at fuel denitrification which, as is well known, is difficult and costly. Moreover, technological improvements can bring considerable progress to this field. That is the case with low NO burners developed at IFF. These consist of producing separated flame jets that enable lower combustion temperatures, local oxygen concentrations to be less high and a lowered fuel s nitrogen contribution to NOj. formation. In a well defined industrial installation, the burner said to be of the low NO type can attain a level of 350 mg/Nm, instead of the 600 mg/Nm with a conventional burner. 

Later on, such S-layer-based sensing layers were also used in the development of optical biosensors (optodes), where the electrochemical transduction principle was replaced by an optical one [97] (Fig. 10c). In this approach an oxygen-sensitive fluorescent dye (ruthenium(II) complex) was immobilized on the S-layer in close proximity to the glucose oxidase-sensing layer [97]. The fluorescence of the Ru(II) complex is dynamically quenched by molecular oxygen. Thus, a decrease in the local oxygen pressure as a result of... 

Contact of barium peroxide and water will readily produce a temperature and a local oxygen concentration high enough to ignite many organic compounds. 

Eor illustration purposes, we consider here a simple scenario of this interplay. We evaluate the effectiveness factor at a fixed cell voltage and thus at a fixed rig. We can express the corresponding current density as a two-variable function, jg =f f, Sqi), where the reaction penetration depth, CL/ depends on rjg. This function can be used to determine the effectiveness factor, rcL- In the case of severely limited oxygen diffusion, the following relations for local oxygen partial pressure and current density can be obtained ... 

As outhned earUer every single step of hematopoiesis is regulated and controlled in vivo by the cell s microenvironment. This not only includes the composition and concentration of growth factors, but also the local oxygen concentration, the pH, the osmolaHty, the supply of nutrients and the cellular and molecular surrounding of the cells (cell-cell contact, adhesion molecules and extracellular matrix). All these parameters affect the fate of the cell and, to estabUsh a cell culture process to cultivate or generate a specific subpopulation, the influence of all these factors has to be considered in the experimental set-up. In the following sections these parameters will be discussed in brief. 

Since the fraction of electrons and holes, although very small, depends on the (local) oxygen potential and since the mobility of the electronic defects is far larger than that of the ionic defects, the electronic conductivity may, by continuously changing the oxygen potential, eventually exceed the ionic conductivity. By definition, the transference number is t-loa = erion/(crion + crei)> which explicitly yields... 

HPCA functions as a cathodic inhibitor by forming an adherent Ca/HPCA barrier film at the cathode. This film is initiated by the relatively high cathodic area pH (as a result of localized oxygen reduction). This product can be expensive to apply, as typically the dose rate is around 8 to 12 ppm as actives. 

A kinetic study of the photosensitized oxidation of tryptophan-alkyl esters in Triton X-100 micellar solutions has been carried out by Criado et al. [24], The results obtained are presented in Table 6. These data show an important decrease in the relevance of the photo-oxidative pathway in the esterified compounds in the presence of the micelles. The magnitude of the effect seems to be extremely sensitive to the location of the probe, increasing as the length of the ester hydrocarbon chain increases. These results are interpreted in terms of the competition between the local oxygen concentration and the solvent micropolarity effect that... 

Experimental frequencies and predicted coupling constants for the local oxygen modes in Si02. 

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