Precursor molecule atmospheric pressure

Fluorinated self-assembled monolayers (F-SAM) can be deposited either in liquid phase, hy dipping the mold direcfly into a diluted solution of anti-sticking molecules [92], or in a vapor phase process. The latter can he done either by thermal evaporation of the liquid precursor at atmospheric pressure [93] or by vacuum evaporation at room temperature [94]. Chlorosilane molecules are very reactive and able to polymerize, producing particles that can precipitate onto the mold. This is why it is preferable to use the vapor phase process with this type of molecules, leading to smoother surfaces [95]. 

Polymers are unique in the extent of the detail of their history which they retain in their morphology, essentially because of the restricted mobility of long molecules once added to a lamella. Indeed polymer morphology has driven almost all advances in understanding the fundamental nature of polymeric self-organization, not least chainfolding. In the present case it demonstrates clearly that polyethylene lamellae crystallized at atmospheric pressure did not have a hexagonal precursor. 

Finally, when using ESI or APCI, it is also possible to perform in-source CID at atmospheric pressure. This is sometimes referred to as pseudo-MS/MS . By increasing the entrance cone voltage, newly formed ions can be accelerated toward the entrance cone, colliding with other molecules, mostly atmospheric nitrogen, and fragmenting. It is important to note that there is no mass selection for a precursor ion and that selection is entirely based on chromatographic separation. 

Since the 1970s, palladium and platinum complexes with dibenzylideneacetone Pd(dba)2 and M2(dba)3 (M = Pd, Pt) have been known to react under mild conditions with either hydrogen or carbon monoxide, with the formation of a metal [211]. Indeed, there exists a long series of examples where CO and H2 have been used to decompose organometallic precursor molecules [173-177,179-181,183,184,186-188, 212-216]. As an example, the decomposition Ru(COD)(COT) (COD = cyclo-octadiene COT =cydo-octatriene) in an atmosphere of hydrogen is worthy of mention [189,190]. (Scheme 3.20). In this case, the precursor molecule is dissolved in a methanol-THF mixture and is contacted with H2 (3 bar pressure) at room temperature for at least 45 min. Depending on the nature of the MeOH-THF mixture, the Ru particle size can be designed between 3 and 86 nm. 

CVD diamond or "low-pressure diamond are synonyms of the term diamond by CVD. Diamond by CVD can be prepared in a variety of ways. Deposition parameters are total (low) pressure, partial hydrogen pressure, precursor molecules in the gas phase, temperature for activation of the hydrogen and that of the surface of the underlying substrate. The energy supply for the hydrogen activation may be, for instance heat, radio frequency, microwave excitation (plasma deposition) or accelerated ions (e.g. Ar ions). CVD diamond has also been obtained at atmospheric pressure from oxyacetylene torches... 

All our preliminary CVD experiments were carried out under an atmosphere of N2 gas in order to determine the intrinsic ability of the studied molecules to serve as precursors to ceramic materials. Further studies could be run under a reactive medium such as H2 in order to reduce the C and O content of the films. This was done in the case of compound 19. Cold-wall CVD experiments on this molecule were performed at 973 K and normal pressure under H2 carrier gas. These experiments resulted in the formation of highly pure VC films.38 XPS and EPMA-WDS analyses of these films showed both the free carbon and oxygen contents to be lower than the limits of detection of the techniques. Various factors can account for these results diminution of the C content induced by H2, stabilization of the Cp ligand in the gas phase due to the presence of f-butyl groups, and decomposition mechanism involving a methyl activation leading to the formation of V = CH2 species.38... 

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