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The rate of disappearance of solvated electrons by reaction with fluorobenzene in ammonia is accelerated by small concentrations of methanol; it also has a “negative activation energy” depending on the methanol concentration. The kinetic data suggest an exothermic electron attachment-detachment equilibrium with the fluorobenzene followed by a slower reaction of the electron adduct with the proton donating methanol. 相似文献
145.
As a first step towards a collective treatment of charge flow in atomic collisions, we constructab initio potential energy surfaces as a function of the internuclear distance and the charge asymmetry between the two atomic species. To this end, the charge asymmetry off its stability value for a given nuclear separation is imposed upon the system by a suitable constraint within a two-centre Hartree-Fock calculation. Energy surfaces are presented for the systems LiH, HF, LiF, and CO. This representation offers a conceptual framework for visualising ionic or covalent molecular states and trajectories describing charge-changing collisions. 相似文献
146.
W.Ken Busfield Ian D. Jenkins San H. Thang Ezio Rizzardo David H. Solomon 《Tetrahedron letters》1985,26(41):5081-5084
95 percent of the reaction of t-butoxy radical with norbornadiene occurs by radical addition followed by rearrangement to nortricyclyl and 7-t-butoxynorbornenyl products; the remainder includes a novel radical rearrangement involving a 1,3-H shift and some radical abstraction observed for the first time. 相似文献
147.
The effect of harmonic forces on Brownian motion in linear shear flow is investigated including a short and intermediate time analysis. A diffusion regime exists for long times if the harmonic forces restrict the motion only in one direction. A series expansion for the effective longitudinal diffusion coefficient is derived for a model of nonlinear uniaxial flows. 相似文献
148.
Álvarez-Caldas C. San Román J. L. Rodríguez-Fernández S. Olmeda E. 《Experimental Techniques》2006,30(4):29-32
Experimental Techniques - 相似文献
149.
A class of non-linear Fokker Planck equations with exactly known steady state solution is investigated and its relation with the models considered earlier in the literature is discussed. A characterisation of the absence of detailed balance and possible existence of limit cycles is given. The implications of detailed balance on the existence and the character of limit cycle behaviour are studied. It is shown that detailed balance does not determine the existence or non-existence of limit cycles but rather their character. 相似文献
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