Nitrogen atoms pressure measurement

Figure 17 shows the chemical structures of anionic amphiphile sodium-1,2-bis (tetradecylcarbonyl)ethane-l-sulfonate (2Cj4SNa)[34] and poly(ethyleneimine)(PEI). A benzene/ethanol (9 1)(WV) solution of anionic amphiphile was spread on the pure water surface or the PEI-water solution (lxlO5 unit M in monomer unit, pH=3.2) surface at a subphase temperature, Tsp of 293 K. At this pH, ca. 70 % of nitrogen atom in PEI molecule was protonated[35]. Surface pressure-area(ji-A) isotherms were measured with a microprocessor controlled film balance system. 

No species with more than two nitrogen atoms was found among the products. The isothermal distillation of the products observed at 77° K. into the mass spectrometer was followed until these products were largely exhausted. The distillation curves are presented in Figure 4, where it is seen that N2, with the highest initial partial pressure, diminishes in concentration (as measured by the mass spectrometric peak intensity) with time whereas F2 appears, and after passing through a maximum, is... 

The mononitride phase has been prepared by several workers (, 5-8, and 11-13) at temperatures as high as 1600 K. X-ray data (6, j ) and dissociation pressure measurements (. ) have shown that the phase has an extensive homogeneity range. Although Kozeurov et al. (7) were unable to obtain VN at 1273 K, Brauer and Schnell (6) and Hahn (JJ ) reported that the composition of the mononitride phase extends from VN to VN (42 to 50 atomic percent nitrogen) at 1273-1873 K. The dissociation pressure data of Kozheurov et al. (7) indicate that the vanadium-rich phase boundary decreases from VN at 1573 K to VNq 50 1923 K. 

For the NO-CO reaction over Rh(111) at high pressures, we find that the reaction is positive order in NO and surprisingly is zero order in CO. As is shown in Fig. 2, from 500 K to 650 K the reaction has an activation energy close to 30 kcal/mole. After reaction the Rh(111) surface is nearly covered with nitrogen atoms. (The nitrogen atom coverage is also high near the rate maximum in low pressure studies [8].) The elementary steps which were used to model the NO-CO reaction shown below were also chosen based on the UHV measurements of the rate constants of each step. 

After some debate between the two, in which Dalton cast doubt on Gay-Lussac s experiments, the conclusion was reached that equal volumes of gas (when measured under the same conditions of temperature and pressure) must contain equal numbers of molecules. This statement (Avogadro 1811), attributable to another great scientist, Amedeo Avogadro (1776-1856), from 1820 Professor of Physics at Turin, was consistent with observation, if it is assumed that simple gases such as oxygen and nitrogen are composed of molecules made up of two atoms, and is now known as Avogadro s... 

The surface nitrogen concentration [N(s)] was measured as a function of time for ammonia pressures of 124 and 1400 Pa. Calculate [N(s>] (atoms/cm2) as a function of time for these two pressures, and compare with experimental values from Ref. [425] (data can be found in the file SiNitridation, csv). Plot theory and experiment on the same graph. Take k2 = 1.5 x 10 4 s 1. 

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