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- Keyword
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- Conservation; endangered species; secure storage; deep freeze; lunar craters; biodiversity; genetic heritage (1)
- GAS-PHASE; CLUSTERS; BENZENE; ASSOCIATION; TRANSITION; ENERGIES (1)
- HOMOGENEOUS NUCLEATION RATES; DENSITY-FUNCTIONAL THEORY; PHASE NUCLEATION; POLAR-MOLECULES; LIQUID-DROPS; N-PROPANOL; MODEL; ACETONITRILE; ETHANOL; TETRACHLORIDE (1)
- INTERMOLECULAR POTENTIAL FUNCTIONS; MOLECULAR-DYNAMICS SIMULATION; SMALL BENZENE CLUSTERS; LIQUID METHANOL; HOMOGENEOUS NUCLEATION; ACETONITRILE CLUSTERS; MONOCLINIC PHASE; (H2O)20 CLUSTERS; MODEL (H2O)8; DROPS (1)
Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Termolecular Proton Transfer Reactions Assisted By Ionic Hydrogen Bond Formation: Reactions Of Aromatic Cations With Polar Molecules, George M. Daly, Michael Mautner, Y. B. Pithawalla, M. Samy El-Shall
Termolecular Proton Transfer Reactions Assisted By Ionic Hydrogen Bond Formation: Reactions Of Aromatic Cations With Polar Molecules, George M. Daly, Michael Mautner, Y. B. Pithawalla, M. Samy El-Shall
Chemistry Publications
We present a new method that applies resonant‐two‐photon ionization to generate reactant ions selectively in the source of a high‐pressure mass spectrometer (R2PI‐HPMS) for kinetic and equilibrium studies. Applications to reactions that would be obscured otherwise in a complex system are illustrated in mixtures of benzene with polar solvent molecules (S). We observe a novel type of proton transferreactions from C6H6 +• to two S molecules where S=CH3CN, CH3OH, C2H5OH and CH3COOC2H5, and from C6H5CH3 +• to two …
Oxidation States And Magnetism Of Fe Nanoparticles Prepared By A Laser Evaporation Technique, B. J. Jönsson, T. Turkki, V. Ström, M. S. El-Shall, K. V. Rao
Oxidation States And Magnetism Of Fe Nanoparticles Prepared By A Laser Evaporation Technique, B. J. Jönsson, T. Turkki, V. Ström, M. S. El-Shall, K. V. Rao
Chemistry Publications
Nanoparticles of iron and iron oxide have been prepared in a thermal diffusion cloud chamber using pulsed laser evaporation. SEM/TEM studies of these particles reveal a size distribution with a mean diameter of about 60 Å. This is consistent with the mean particle size estimated from the magnetic data. The oxidation levels of these nanoparticles prepared at different partial oxygen pressures were investigated using FTIR. All the samples are found to exhibit superparamagnetism with blocking temperatures ranging from 50 K to above room temperature. Magnetic anisotropy constants are calculated from the frequency dependence of the blocking temperatures are found to …
Condensation Of Supersaturated Vapors Of Hydrogen Bonding Molecules: Ethylene Glycol, Propylene Glycol, Trimethylene Glycol, And Glycerol, David B. Kane, M. Samy El-Shall
Condensation Of Supersaturated Vapors Of Hydrogen Bonding Molecules: Ethylene Glycol, Propylene Glycol, Trimethylene Glycol, And Glycerol, David B. Kane, M. Samy El-Shall
Chemistry Publications
The critical supersaturations required for the homogeneous nucleation (rate of 1 drop cm−3 s−1) of ethylene glycol, propylene glycol, trimethylene glycol and glycerol vapors have been measured over wide temperature ranges (e.g., 280–400 K) using an upward thermal diffusion cloud chamber. At lower temperatures the experimental nucleation rates are much higher than the predictions of the classical nucleation theory. Glycerol shows the best agreement between experiment and theory in the temperature range of 340–370 K. An apparent increase in the critical supersaturation of glycerol is observed with increasing carrier gas (helium) pressure and this effect is more …
A Monte Carlo Study Of Methanol Clusters (Ch3oh)N, N=5-256, D. Wright, M. S. El-Shall
A Monte Carlo Study Of Methanol Clusters (Ch3oh)N, N=5-256, D. Wright, M. S. El-Shall
Chemistry Publications
The thermodynamic and structural properties of methanol clusters (CH3OH) N , N=5–15, 20, 30, 60, 128, 256 and the bulk liquid have been investigated using Monte Carlo simulation. Calculated properties as a function of size include electrostatic and dispersive contributions to the configurational energy, configurational heat capacities,fractal dimension, density profiles, order parameters characterizing dipole and bond vector orientation, and the Lindemann index. The clusterheat capacities as a function of N possess an interior maximum near N=128 and converge to the bulk value from above. Monocyclic, semiplanar structures are found to persist at liquidlike temperatures up to …
Space-Based Genetic Cryoconservation Of Endangered Species, Michael Noah Mautner
Space-Based Genetic Cryoconservation Of Endangered Species, Michael Noah Mautner
Chemistry Publications
Genetic materials of endangered species must be maintained, for cryoconservation, permanently near liquid nitrogen temperatures below 77 K. Due to the instability of human institutions, permanent safety is best provided at storage sites that maintain passively the needed low temperatures, and provide barriers to access. The required conditions are available in permanently shaded polar lunar craters with equilibrium temperatures of 8 to 40 K, on the moons of Saturn, and unshielded storage satellites. A genetic depository can be incorporated readily into planned lunar programmes.