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The existence of a primordial, undegassed lower mantle reservoir characterized by high concentration of He-3 and high He-3/He-4 ratios is a cornerstone assumption in modern geochemistry. It has become standard practice to interpret high He-3/He-4 ratios in ...
The prediction of the thermal energy confinement time, tau(th), for ITER size experiments is based on power law scalings obtained using data sets of present tokamak results in specific regimes, the most relevant being the ELMy H mode regime. A thorough sta ...
The Joint European Torus (JET) has recently operated with deuterium-tritium (DT) mixtures, carried out an International Thermonuclear Experimental Reactor (ITER) physics campaign in hydrogen, deuterium, DT and tritium, installed the Mark IIGB 'Gas Box' div ...
We have studied infrared multiphoton dissociation of CF3H pre-excited to the second C-H stretch overtone under collisional conditions in view of developing a laser isotope separation scheme for carbon-13. This single stage process results in a C2F4 product ...
We have studied the synthesis and stability of the monooxygenase AlkB of Pseudomonas oleovorans in its natural host and in recombinant Escherichia coli. Three strains were investigated: the prototype strain P. oleovorans and the E. coli alk+ recombinants H ...
Isotope sepn. was demonstrated following the selective IR laser-induced photodissocn. of van der Waals clusters in a free jet. Irradn. of a natural abundance mixt. of SF6 isotopomers dild. in Ar with a 20-W cw CO2 laser gave overall enrichment factors >1.1 ...
Investigations on a polished thin section (PTS) by reflected-light microscopy, laser micro-Raman spectroscopy, and cathodoluminescence of the Bencubbin meteorite revealed the presence of diamond grains ranging in size from 200 nm to 1 mum in Fe-Ni metal, s ...
We use mass-resolved 2+2 resonantly enhanced multiphoton ionization (REMPD of silicon atoms to detect isotopically selective infrared multiphoton dissociation (IRMPD) of both ground-state and vibrationally pre-excited SiH4. To demonstrate that the detectio ...
A threshold near 6.8 eV is obsd. for the dissocn. of H2O (and D2O) via the repulsive A(1B1) potential in rare gas matrixes. The threshold varies within 0.2 eV for exchange of Kr with Ar matrix, upon deuteration, and with temp. The observations are consiste ...
Selective IR vibrational predissocn. (IRVP) of van der Waals clusters in a free jet is an effective way to sep. isotopes. Abs. sepn. factors a in excess of 1.1 were obsd. upon irradn. of a beam of SF6 dild. in Ar with a 20 W CO2 laser. Selection of the wav ...