Reaction of t-butoxy radicals with norbornadiene

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.     

The vibrational excitation of hydrogen fluoride behind incident shock waves

The vibrational excitation of HF occurring behind incident shock waves has been studied in the temperature range of 1400°K to 4100°K. The extent of excitation was determined as a function of time by continuously monitoring the emission intensity from the 1–0 band of HF centered at 2.5 μ. The data were interpreted in terms of the process and gave a value of for M = HF. The corresponding result for (τp)^?1_Ar was found to be insignificant in comparison to this result. Data were also obtained for the effect of F atoms upon the relaxation rate, i.e., it was found that      

Optically induced electron spin resonance in doped amorphous silicon

We report the first observations of optically induced electron spin resonance signals in doped and undoped amorphous silicon. We also report the observation of equilibrium surface or interface spin densities ～ 10¹³cm^?2 and volume spin densities ～ 6 × 10¹⁵ cm^?3. The small number of spins observed in equilibrium compared to the large optically induced spin density shows that most electrons are spin paired in equilibrium. We conclude that this implies a very small mean effective correlation energy, U ～ kT.     

Advanced and retarded solutions in field theory

The appearance of retarded and advanced solutions to the wave equation and thead hoc choice of one of them in preference to the other has led to the claim that electromagnetic theory is incomplete. It is contended that some other condition outside that theory must be invoked in order to make a meaningful physical choice. However, both a physical and mathematical analysis show, that, in fact, both retarded and advanced solutions are necessary and that the rejection of the advanced type of solution is not valid; that its rejection is based on an ambiguous mathematical technique and a faulty physical interpretation. A unique form for the Green's function is obtained which is related to all other types of Green's functions by the appropriate adjunction of solutions to the homogeneous equation.