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[en] Using a relatively simple semiclassical model, it is shown that transient, induced molecular negative ions (TIMNI), are produced through a potential barrier interaction between cold electron collisions and polarizable molecules in plasma. Such new negative ions lead to radio-frequency absorption in such discharges. The calculated radio-frequency absorption frequencies are consistent with earlier experimental measurements. (authors)
[en] The establishment of a mass mobility correlation for ions of the series H+ (H2O)sub(n) obtained by means of a device whereby a reaction chamber operating under atmospheric pressure is coupled with a mass spectrometer, has enabled to observe the transition between discrete mobilities of ions H+ (H2O)4 and H+ (H2O)5 and a mean mobility corresponding to the equilibrium
[fr]L'etablissement d'une correlation masse-mobilite pour les ions de la serie H+ (H2O)sub(n) realisee a l'aide d'un dispositif couplant une chambre de reaction fonctionnant a pression atmospherique et un spectrometre de masse, a permis de mettre en evidence la transition entre les mobilites discretes des ions H+ (H2O)4 et H+ (H2O)5 et une mobilite moyenne correspondant a l'equilibre
[en] Rate coefficients and product distributions for the reactions of CO+2 and CO2 x CO+2 with C2H4 were determined in a drift chamber filled with CO2 at 0.3 torr. The rate coefficients are k3 = 0.9 x 10-9 cm3 s-1 for CO+2 and k5 = 1.0 x 10-9 cm3 s-1 for CO2 x CO+2. The products from the first reactionare C2H+4 (17%), C2H+2 (56%) and C2H+3 (27%). The fragmentation pattern is in good agreement with the breakdown diagram of ethylene. The second reaction yields only C2H+4 as a product. It is concluded that the ion-electron recombination energy of CO2 x CO+2 is smaller than the appearance potential of C2H+2 from ethylene, 13.13 eV. From this result and the previous observation that CO2 x CO+2 reacts with N2O by charge transfer we derive the dissociation energy of CO2 x CO+2 as 75.3 +- 11.6 kJ mol-1 and its heat of formation as 468.6 +- 11.6 kJ mol-1. (orig.)
[en] Mass-analyzed threshold ionization (MATI) technique is optimized to generate substantial amount of state-selected molecular ions sufficient for dynamics study. The main strategy is to stabilize intermediate (n= 100-200) Rydberg states by l,m-mixing induced by AC field. Electrical jitter inherent in high voltage switching is utilized for this purpose. A related technique to locate the MATI onset is also described
[en] The formation and decay of HO2 and O2- transients was reinvestigated using oxygenated aqueous t-butanol solutions in the pH range from 1.5 to about 8. The obtained spectroscopic and kinetic characteristics of both superoxide radical forms are: for HO2 lambdasub(max) = 230 nm (epsilon230 = 130 m2mol-1), 2k (HO2 + HO2) = (3.7 +- 0.2) x 106 dm3mol-1S-1, and for O2- lambdasub(max) = 245 nm (epsilon245 = 215 m2mol-1), 2k (O2- + O2-) < 10 dm3mol-1s-1. (orig.)
[en] The main factors affecting the pathways of multistep cationic molecular rearrangements of natural terpenes and their analogues are considered. Methods for predicting the most probable pathways of cationic rearrangements are proposed. The bibliography includes 85 references.
[en] In this work, it was so particularly interested in exploring cultivable bacteria isolated from a digested sludge of an anaerobic digester. The characterization of the bacteria is determined by: The classic microbiology and molecular biology, with a study of radio-resistance profile of these bacteria.