Phase Uncertain

Continuous Phase Uncertain Some situations exist such as in... 

Fig. 9. The plutonium—oxygen phase diagram where L = Hquid a, P, y, 5, and S are metal phases and the dashed lines represent uncertain phase...

Tubular reactors have been the main tools to study continuous flow processes for vapor or gas-phase reactions. These are also used for reaction in tv o flowing phases over a solid catalyst. When the catalyst is in a fixed bed, the contact between the liquid on the outside surface of the particulate is uncertain. For slurry-type solid catalyst the residence time of the catalyst or the quantity in the reactor volume can be undefined. 

Sulfide Stress Cracking) on steels over Rockwell C 22. (4) static stresses. other equipment handling sour gas, oil and/or water wherein H2S and H2O (liquid phase) are present up to about 150 F, where sulfide stress cracking slows down perceptibly. stainless steels with Rockwell hardness over C 22. (4) into crystal structure, exact mechanism uncertain. Sulfur expedites absorption of atomic H into grain structure. (4) if feasible use inhibitors and/or resistant coatings where feasible time or heating up will permit H to diffuse out but will not relieve any areas when H2 has concentrated. 

No other oxide phases below MO2 have been established but a yellow hydroxide , precipitated by alkali from aqueous solutions of chromium(II), spontaneously evolves H2 and forms a chromium(III) species of uncertain composition. The sulfides, selenides and tellurides of this triad are considered on p. 1017. 

The dominant interactions that take place with this novel phase are not clear. There will obviously be dispersive interactions with the propyl chain and some polar interactions with the amino group. Whether there are ionic interactions taking place as well is uncertain but, nevertheless, the material affects an excellent separation of glucose and fructose and this remains a baseline separation even when the two sugars are both present at about the 5% level. 

Replacement of gas by the nonpolar (e.g., hydrocarbon) phase (oil phase) has been sometimes used to modify the interactions among molecules in a spread film of long-chain substances. The nonpolar solvent/water interface possesses an advantage over that between gas and water in that cohesion (i.e., interactions between adsorbed molecules) due to dipole and van der Waals s forces is negligible. Thus, at the oil/water interfaces, the behavior of adsorbates is much more ideal, but quantitative interpretation may be uncertain, in particular for the higher chains, which are predominantly dissolved in the oil phase to an unknown extent. The oil phase is poured on the surface of an aqueous solution. Thus, the hydrocarbon, such as heptane or decane, forms a membrane a few millimeters thick. It is thicker than the adsorbed monolayer. Owing to the small difference in dielectric constant between the air and a hydrocarbon oil, the... 

Wood and Hill consider that the role of fluoride in these glasses is uncertain. Phase-separation studies suggest that the structure of the glass might relate to the crystalline species formed, in which case a microcrystallite glass model is appropriate. But other evidence cited above on the structure-breaking role of fluoride is compatible with a random network model. 

In addition to these problems, there are specific chemical problems, raised by our uncertain knowledge of the gas-phase chemistry and alluded to in the previous discussion of ion-molecule chemistry, which make the gas-phase model results highly uncertain in many instances. These are now discussed in more detail, in the hope that they can be alleviated by future laboratory and theoretical work. 

As discussed in Section II, neutral-neutral reactions involving atoms and/or small radicals play an uncertain role in the gas-phase chemistry of interstellar... 

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