Electrochemical oxidation of 1-chloro(bromo)-2,2,6,6-tetramethylpiperidines

Electrochemical oxidation of 1-haloamines of the 2,2,6,6-tetramethylpiperidine series results in the formation of relatively stable radical-cations, detected by the methods of cyclic voltammetry and ESR spectroscopy. The final products of electrochemical oxidation of these haloamines are stable nitroxyl radicals.     

Observation of B-->K(0)(S)pi(+)pi(-) and Evidence for B-->K(*+/-)pi(-/+)

We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6).     

Results of Experiments on Modification of the Sporadic E-Layer by Powerful HF Radio Waves

We present the results of experiments on modification of the sporadic E-layer of the Earth's ionosphere by a powerful vertical beam of HF radio waves. The experiments were performed at the Sura heating facility (Radiophysical Research Institute, Nizhny Novgorod) from May 31 to June 4, 2001. The main results were obtained in May 31 from 17:30 to 20:00 MSK, when the E_s layer was fairly stable and the pump frequency was in the range where this layer was transparent. The diagnostics of the ionosphere was performed using X-mode probe waves in the frequency range f_pr=4.3-7.8 MHz. The ionosphere plasma heating was accompanied by an increase in the intensity of probe waves, reflected from the E_s layer, with frequencies close to or slightly higher than the critical frequency of the layer. Artificial fluctuations of the reflected signal appeared in the entire frequency range of sounding. We consider the dynamical characteristics of the observed phenomena and their dependence on the frequency f_pr and the parameters of the E_s layer.     

Menisci in a Diamond-Shaped Capillary

This paper presents a closed form analytical solution to the augmented Young-Laplace equation for the meniscus profile in a capillary formed between four equal-sized tangent cylinders centered on the vertices of a square. The solution is valid for a large class of disjoining pressure isotherms and contact angles.     

Spontaneous and stimulated emission of radiation from hot holes from uniaxially stressed germanium

Far-infrared radiation from hot holes in Ge under streaming conditions is investigated. Stimulated emission is observed from uniaxially compressed samples without magnetic field. The existence of inversion is due to a strain splitting of the light and heavy hole bands.     

The Photochemical Methylenecyclopropane Rearrangement of Feist's Ester

In contrast to the thermal rearrangement, the photochemically induced methylenecyclopropane rearrangement of diethyl trans-methylenecyclopropane-2,3-dicarboxylate (I) and of ethyl ethoxycarbonylcyclopropylideneacetate (syn or anti) produced diethyl cis-methylenecyclopropane-2,3-dicarboxylate. A true photoequilibrium was not observed.