High spin states in 74Se

Gamma-ray transitions from the bombardment of ⁶⁴Ni by ¹⁶O up to 81 Me V were studied in a variety of experiments. Four transitions in coincidence with four previously known transitions in ⁷⁴Se were discovered. Information on energies, angular distributions, intensities multiplicities and lifetimes is given for these transitions. Excitation functions for this and several other channels are presented. Statistical calculations are in satisfactory agreement with experiment.     

Heavy ion induced transfer reactions on 148Nd

Transfer reactions induced by ¹⁶O and ¹⁸O beams on ¹⁴⁸Nd were measured with a time-of-flight setup at 72 MeV incident energy. The angular distributions are bell shapes having their maxima at angles somewhat below the grazing angle. The excitation in the final nuclei takes place (if possible) near the optimum Q-value and is spread over 5 MeV for the one-particle transfer reactions and up to 10 MeV for the multiparticle transfers. The cross sections for the individual channels are explained mostly by Q-window considerations. In spite of the differences in the individual channels the total transfer cross section integrated over excitation energy, angle, and all channels turns out to be the same same for both ¹⁶O and ¹⁸O beams. This cross section amounts to 20 % of the total reaction cross section and nicely fills the gap between the measured fusion cross section and the total reaction cross section obtained from optical model calculations based on elastic scattering data.     

Interactions of endoglucanases with amorphous cellulose films resolved by neutron reflectometry and quartz crystal microbalance with dissipation monitoring

A study of the interaction of four endoglucanases with amorphous cellulose films by neutron reflectometry (NR) and quartz crystal microbalance with dissipation monitoring (QCM-D) is reported. The endoglucanases include a mesophilic fungal endoglucanase (Cel45A from H. insolens), a processive endoglucanase from a marine bacterium (Cel5H from S. degradans ), and two from thermophilic bacteria (Cel9A from A. acidocaldarius and Cel5A from T. maritima ). The use of amorphous cellulose is motivated by the promise of ionic liquid pretreatment as a second generation technology that disrupts the native crystalline structure of cellulose. The endoglucanases displayed highly diverse behavior. Cel45A and Cel5H, which possess carbohydrate-binding modules (CBMs), penetrated and digested within the bulk of the films to a far greater extent than Cel9A and Cel5A, which lack CBMs. While both Cel45A and Cel5H were active within the bulk of the films, striking differences were observed. With Cel45A, substantial film expansion and interfacial broadening were observed, whereas for Cel5H the film thickness decreased with little interfacial broadening. These results are consistent with Cel45A digesting within the interior of cellulose chains as a classic endoglucanase, and Cel5H digesting predominantly at chain ends consistent with its designation as a processive endoglucanase.     

Mechanical and optical viscoelastic characterization of Hysol 4290

Mechanical and optical characterization of Hysol 4290 as a function of time and temperature is presented. The kinetic theory of polymers, the Williams, Landel and Ferry equation and the time-temperature superposition principle, is discussed. Rubber-like elasticity is used as a simple experimental method to ascertain if the time-temperature superposition should be expected to apply. Finally, the glass-transition temperature of Hysol 4290 is established and its importance in correctly assessing experimental data is discussed.     

Classical microscopic description of U + U collisions

Calculations simulating head-on collisions between two mass-235 nuclei are made using classical kinematics, Monte-Carlo methods, and nucleon-nucleon cross sections. The calculated ratio of maximum particle density to the pre-collision nuclear density is ≈ 2 or 3, depending on details of the nucleon-nucleon scattering mechanism used.     

Amperometric detection of thiopurines in blood plasma with a cobalt-phthalocyanine chemically modified electrode after liquid chromatography

Cobalt phthalocyanine-containing carbon paste electrodes are used as electrocatalytic amperometric sensors for 6-mercaptopurine, 6-thioguanine, and several related thiopurines in blood plasma after separation by liquid chromatography. Required sample preparation is minimal, and total quantitation time is 8 min or less. Detection limits are 1.5–8 pmol, approximately an order of magnitude better than that obtained with ultraviolet or fluorescence detection.