Nitrogen, atmospheric, deposition

A typical example of reactive evaporation is the deposition of TiN. The source is evaporated resistively or more commonly by electron-beam heating in a nitrogen atmosphere.Deposition rate is reduced with... 

Precipitation over North America gradually becomes more acidic from west to east, especially in industrialized areas of the Northeast. This acid rain may be a result of the release of nitrogen and sulfur oxides into the atmosphere. The colors and numbers (see key) indicate pH measured at field laboratories in 2004. Data from National Atmospheric Deposition Program/National Trends Network http //nadp.sws.uiuc.edu. 

The optimum deposition temperature is 850°C. Pressure may be up to 1 atm. A hydrogen or nitrogen atmosphere is used with very high ratio of N2 to reactants (ca. 1000/1). 

Deposition of TiN by the thermal decomposition of tetrakis(dimethylamido)titanium (TDMAT) in a nitrogen atmosphere (as opposed to ammonia) was characterized by a simple Arrhenius rate expression. Adequate deposition rates and good step coverage were achieved for 3/1 aspect ratio holes, 0.40 micron in size. A reactor model was designed,... 

Chlorinated dioxins occur in atmospheric deposition (Koester and Hites 1992), and will thereby enter the terrestrial environment and watercourses. The degradation of tetrachloro- through octa-chlorodibenzo[l,4]dioxins has been examined in low-nitrogen medium by Phanerochaete sor-dida YK-624 (Takada et al. 1996). All the compounds were extensively degraded, and the ring fission of 2,3,7,8-tetra- and octachlorodibenzo[l,4]dioxin produced 4,5-di- and tetrachlorocatechol. These results established important evidence for the biodegradability of even highly chlorinated dibenzodioxins. 

The first type of equipment for SILAR was that described by Nicolau,1 who arranged alternating reaction and rinsing vessels in a circle (Fig. 8.2). During the deposition, the vessels and the substrate are placed under a hood in a nitrogen atmosphere and the substrate is lifted and rotated from one vessel to another by two electric motors. The rinsing water is circulated from a reservoir to the rinsing vessels with the aid of a peristaltic pump.1,9... 

When nitrogen input owed to mineralization and atmospheric deposition exceeds the demand of both the vegetation and the microbes in undisturbed maturated forest... 

Since the composition of atmospheric deposition always includes specific amounts of base cations, in addition to critical loads it is necessary to calculate the actual acidifying effect of depositions. For the quantitative assessment the latter effect the critical deposition values should be estimated using the following formulas for sulfur and nitrogen ... 

Figure 8.13. Polarization data in the vicinity of the mixed potential for electroless copper deposition 0.05 M CUSO4, 0.15 M EDTA, 0.072 M HCHO, NaOH to pH 12.50, nitrogen atmosphere, 25°C. (From Ref. 34, with permission from the Electrochemical Society.)...

Watersheds are generally several orders of magnitude larger than the surface waters that drain them. Thus most of the atmospheric deposition that may potentially enter aquatic systems falls first on some portion of the watershed. Nitrogen may be deposited to the watershed or directly to water surfaces... 

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