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KH2PO4 single crystals have been studied by employing complex impedance measurements in view of the domain freezing effect. As a result, distinct behaviors of the anisotropic domain-wall dynamics in the activation energy of domain freezing and the Vogel–Fulcher temperature before and after proton irradiation have been identified in the anisotropic crystal structure.

The Coaxial Slow Source (CSS) is a device in which 'annular' FRCs, i.e. small aspect ratio, highly elongated plasmas with poloidal fields only, are formed in the annular space between concentric coils carrying toroidal currents. The device is constructed so that the plasma can be translated into a simple cylindrical chamber and re-formed as a true FRC. The goal of the investigation is to form FRCs on slow (diffusive) time-scales and at low voltage. Initial operation shows that the desired configurations are formed over a wide range of coil voltages and fill pressures. The radial plasma position can be controlled. Configuration lifetimes are 30-60 μs, with flux lifetimes of 15-20 μs. Flux is built up over 25 μs, at loop voltages of 1-2 kV, in comparison with 2.5 μs and 100 kV for comparably sized field reversed theta pinches conventionally employed for FRC generation.

The specific complex between the lambda phage OR3 operator and the Cro protein has been studied by proton NMR spectroscopy at 500 MHz. The DNA imino proton resonances of this complex have been assigned to specific base pairs using the known assignments of these resonances for the free operator. Increase of the protein/DNA ratio to complete saturation of the OR3 operator with the Cro protein made it possible to follow the shift changes of the resonances. Ambiguities were resolved by nuclear Overhauser effect measurements on the complex. The shifts of the imino proton resonance positions provide information on the changes induced in the conformation of the operator upon complex formation with a dimer of the Cro protein. The most striking shift occurs for the central (GC 9) base pair, which is known to have no direct contacts with the Cro protein. This shift may be induced by a bend in the OR3 operator DNA at the GC 9 base pair to accommodate the operator for the binding of the Cro protein dimer. The imino proton resonances of two additional base pairs can be observed in the complex, demonstrating an overall stabilization of the DNA structure by the binding of the Cro protein.

Since both acceleration and compression are required for an Inertial Fusion Driver, the understanding of their effect on the beam quality, emittance, is important. This report attempts to generalize the usual emittance formula for the drifting beam to include these effects. The derivation of the 2-D emittance equation is carried out and a comparison with the particle code results is given. The 2-D emittance at a given axial location is reasonable to consider for a long beam, particularly with velocity tilt; transverse emittance averaged over the entire bunch is not a useful quantity. 6 refs., 2 figs., 1 tab.