The molecular structure and conformation of cellulose II (Fortisan) using accurate X-ray diffraction intensities

The previous Polymer Diffraction Symposium saw the use of x-ray film data array calculations to obtain diffraction intensities with computed accuracies. Subsequently, methods for geometrical deconvolution of overlapped diffraction spots have been developed. The techniques have now been applied to data arrays from films of Fortisan. Severely overlapped reflection arcs were splined and transformed into polar coordinate space, yielding orthogonalized diffraction spot groups. Spots were then identified     

Alternate method of source preparation for alpha spectrometry: no electrodeposition,no hydrofluoric acid

Journal of Radioanalytical and Nuclear Chemistry - An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride...     

CO(2) capture by a task-specific ionic liquid

Reaction of 1-butyl imidazole with 3-bromopropylamine hydrobromide, followed by workup and anion exchange, yields a new room temperature ionic liquid incorporating a cation with an appended amine group. The new ionic liquid reacts reversibly with CO2, reversibly sequestering the gas as a carbamate salt. The new ionic liquid, which can be repeatedly recycled in this role, is comparable in efficiency for CO2 capture to commercial amine sequestering reagents, and yet is nonvolatile and does not require water to function.     

Statistical properties of many-particle spectra. II. Two-point correlations and fluctuations

The two-point correlation function for complex spectra described by the Gaussian Orthogonal Ensemble (GOE) is calculated, and its essential simplicity displayed, by an elementary procedure which derives from orthogonal invariance and the dominance of intrinsic binary correlations. The resultant function is used for an approximate calculation of the standard fluctuation measures. Good agreements are found with exact results where these are available, this incidentally demonstrating that the measures are, for the most part, two-point measures. It is shown that they vary slowly over the spectrum, a result which is in agreement both with experiment and with Monte Carlo calculations. The same technique can be used for higher-order correlation functions, and possibly also for more complicated ensembles in which case the results would be relevant to the question why GOE fluctuations give a good account of experimental results.     

Optically sectioned fluorescence lifetime imaging using a Nipkow disk microscope and a tunable ultrafast continuum excitation source

We demonstrate an optically sectioned fluorescence lifetime imaging microscope with a wide-field detector, using a convenient, continuously tunable (435-1150 nm) ultrafast source for fluorescence imaging applications that is derived from a visible supercontinuum generated in a microstructured fiber.     

Local optical properties, electron densities, and london dispersion energies of atomically structured grain boundaries

Quantitative analysis of spatially resolved valence electron energy-loss spectra shows strong physical property contrasts for Sigma5 and near Sigma13 grain boundaries in Fe-doped SrTiO3, resulting in London dispersion interaction energies of 14 to 50 mJ/m(2) between the adjacent grains. The determination of local physical properties of grain boundary cores and the appreciable contribution of long-range London dispersion to interface energies provides new information on formation and control of interfaces in materials.