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The neutron diffraction shows that 49% of the main chain exposed nitrogens exchange their hydrogen atoms with heavy water molecules. The neutron maps illustrate that the protein possesses a number of buried ionized carboxylate groups, suggesting mechanistic implications of the protonated Asp 215 and negatively charged Asp 32.

Issues concerning the use of physicist's tools to enhance understanding of the properties of earth materials and earth processes are presented. Reference is made to the use of synchrotron radiation and neutron radiation.

Hot-atom chemistry by neutron irradiation of 3He has been used to undertake tritium incorporation inside C60. The amount of radiation damage was substantially smaller than was seen from the irradiation of the 6Li salt of C60.

The spatial distributions of individual polymers in multicomponent modified electrodes are determined using neutron reflectivity. A probe of the buried polymer/polymer interfaces reveals that both bilayers has electropolymerized poly(2,2'-bithiopene) as an inner, mediating layer. The outer layer is comprised of either electropolymerized polypyrrole or electroprecipitated polyxylylviologen. Neutron reflectivity data demonstrate that the very different current-potential behaviors of these devices is a consequence of the fabrication method and the consequent polymer/polymer interfacial structure. A composite structure is observed for the polybithiophene/polypyrrole film, while polybithiophene/polyxylylviologen forms a film consisting of segregated polymer layers.

The integrated application of experimentation, inelastic neutron scattering and the computational molecular mechanics (MM3) model were used to evaluate the 2:1 inclusion complex of calixarenes. Results show different spectral signatures between the 2:1 inclusion complex of p-tert-butylcalix[4]arene and p-xylene and the hypothetical 1:1 complex. The variation is attributed to the intense band identified only with p-xylene.

An unfolding procedure is proposed which aims at obtaining spectral information of a neutron radiation field by the analysis of the response of a multi-element system consisting of converter type semiconductors. For the unfolding procedure an artificial neural network (feed forward network), trained by the back-propagation method, was used. The response functions of the single elements to neutron radiation were calculated by application of a computational model for an energy range from [10.sup.-2] eV to 10 MeV. The training of the artificial neural network was based on the computation of responses of a six-element system for a set of 300 neutron spectra and the application of the back-propagation method. The validation was performed by the unfolding of 100 computed responses. Two unfolding examples were pointed out for the determination of the neutron spectra. The spectra resulting from the unfolding procedure agree well with the original spectra used for the response computation.

The design and structural characterization of modulated heterostructure films based on conjugated polymers by means of x-ray and neutron reflectivity were investigated. Positively charged prepolymer of D-PPV, polyanion SPS and polycation PAH were used as polyelectrolytes to fabricate the self-assembled heterostructures. Results revealed quasi-Bragg reflections and higher harmonics in both neutron and x-ray reflectivity of the self-assembled films, implying that ordered superlattice structures were perpendicular to the plane of the films.

The SPR III bare cavity spectrum and integral parameters have been determined with 24 measured spectrum sensor responses and an independent, detailed, transport calculation. This environment qualifies as a benchmark field for electronic parts testing.

The guanosine 5'-monophosphate, dipotassium salt, is considered and G-quadruplexes in hexagonal phase are prepared. The very large K ions concentration difference between the binding sites and the bulk solution demonstrates that counterions are structurally involved in the formation and in the stabilization of the helices.

The phase transitions and structure of La-modified Pb(ZrTi)O3 (PLZT) at 40 K are investigated using high-resolution powder diffraction. The low temperature phase of PLZT 7/65/35 was determined to have triclinic symmetry.

The ground-state properties of the pentameric Co(II) cluster [Co3W(D2O)2(CoW9O34)2](sub 12-) were investigated by inelastic neutron scattering(INS). Spectroscopic techniques are used to determine energy splittings caused by exchange interactions and after this the energy level pattern is reproduced by the eigenvalues of an appropriate effective spin Hamiltonian.