Ab initio and DFT methods have been used to study the seven tautomeric forms of 5-methylcytosine molecule.The related tautomer in gas phase have been studied at HF/6-31G, HF/6-31G* and B3LYP/6-31G* levels oftheory. The structures,enthalpies,entropies,Gibbs free energies,relative tautomerization energies of tautomersand tautomeric equilibrium constants were compared and analyzed along with full ...

The chemical vapor deposition of polycrystalline carbon nitride in stagnation flow reactors is simulated. A model is used to predict the gas phase chemistry, temperature and velocity profiles, potential gaseous film growth precursors, and to evaluate the likelihood of bond rearrangement occurring in the bulk phase or on the deposition surface once the gaseous precursors are adsorbed. Numerical ...

prepared for the IMA Workshop on High-Speed Combustion in Gaseous and Condensed Phase Energetic Materials, Minneapolis, November 8–12, 1999

We are motivated to model chemical vapor deposition for metallic bipolar plates and optimization to deposit a homogeneous layer. Moreover a constraint to the deposition process is a very low pressure (nearly vacuum) and a low temperature (about 400 K). These constraints need to have a catalyst process, here in our apparatus we deal with a plasma source and precursor gases, see (Dobkin and Zuraw...

LPCVD is a process used in the manufacturing of the deposition of thin films on semiconductors usually ranging from a few nanometers to many micrometers. LPCVD is used to deposit a wide range of possible film compositions with good conformal step coverage. These films include a variety of materials including polysilicon for gate contacts, thick oxides used for isolation, doped oxides for global...

Hydrogen molecules dissolved in rubber due to high-pressure hydrogen gas exposure have been analyzed using 1H nuclear magnetic resonance (NMR) with solution and solid-state probes. To analyze the characteristics of dissolved hydrogen in rubber materials and to compare them with gaseous phase hydrogen, we measured the NMR spectra of gaseous phase hydrogen and evaluated the chemical shifts and pr...

Parahydrogen-induced polarization (PHIP) was used to demonstrate the concept that highly polarized, catalyst-free fluids can be obtained in a catalysis-free regime using a chemical reaction with molecular addition of parahydrogen to a water-soluble Rh(I) complex carrying a payload of compound with unsaturated (C═C) bonds. Hydrogenation of norbornadiene leads to formation of norbornene, which is...