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No abstract available

[en] The unidirectionally solidified microstructure of the Ni--Nb eutectic alloy consists of alternate lamellae of Ni₃Nb (delta) and Ni--Nb solid solution (γ) phases. Nb has a solubility limit in γ phase that decreases with temperature, suggesting the possibility of obtaining additional delta phase and strength via precipitation processes. To this end, the microstructure, γ phase lattice parameter and microhardness of the aligned composite were examined in the as-grown, solution treated (ST), and ST + aged conditions. Little precipitation was found after a ten hour 1000⁰C aging treatment in the as-grown ingots. However, approximately 12 vol percent of Widmanstatten delta precipitates--[111]/sub γ/ habit planes--was produced after a 1220⁰C solution treatment followed by short time aging at 1000⁰C. Considerable precipitation was found also after longer time aging at 800⁰C. Lattice parameter measurements indicate the γ phase to be in a metastable, supersaturated condition. Upon ST + aging, the γ lattice parameter decreases slightly, reflecting the Nb loss associated with delta precipitation. The remaining solubility of Nb in γ is compared with previously reported results. The microhardness of the composite was determined as a function of heat treatment and found to increase with increasing vol percent of delta (original lamellae + precipitates). A significant precipitation hardening effect was noted for the ST + 800⁰C aging treatment with hardness measurements suggesting a substantial increase in yield strength

[en] Tight tolerances were placed upon non-linearities in the SPS magnet system and sextupoles installed to adjust the chromaticity of the machine. These sextupoles together with octupoles and active damping were used to adjust the SPS beam dynamics and to damp and suppress both multibunch and single bunch transverse instabilities up to 10¹³ protons per pulse

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[en] In order to bring the SPS to its design intensity of 10¹³ protons per burst, tuning procedure and devices used during the running of accelerator are described. Chromaticity of sextupoles and octupoles was used for the Landau damping and small multipole correcting magnets were used in regular operation for stopband correction. A set of skew quadrupoles was used to compensate coupling at injection. It is proposed that the ''resistive wall'' instability is due to the finite wall conductivity of the vacuum chamber. Future improvements of storing higher intensities are discussed

[en] Under EPRI sponsorship, an industry committee, similar in form and operation to other guideline committees, was created to develop Condensate Polishing Guidelines for both PWR and BWR systems. The committee reviewed the available utility and water treatment industry experience on system design and performance and incorporated operational and state-of-the-art information into document. These guidelines help utilities to optimize present condensate polisher designs as well as be a resource for retrofits or new construction. These guidelines present information that has not previously been presented in any consensus industry document. The committee generated guidelines that cover both deep bed and powdered resin systems as an integral part of the chemistry of PWR and BWR plants. The guidelines are separated into sections that deal with the basis for condensate polishing, system design, resin design and application, data management and performance and management responsibilities

[en] The mass of ¹¹Li has been determined from Q-value measurements of the ¹H(¹¹Li,⁹Li)³H reaction. The experiment was performed at TRIUMF laboratory with the GANIL active target MAYA. Energy-energy and angle-angle kinematics reconstruction give a Q value of 8.119(22) MeV for the reaction. The derived ¹¹Li two-neutron separation energy is S_2n=363(22) keV

[en] The cross section for the fusion of ⁹Li with ⁷⁰Zn was measured for seven projectile energies spanning the subbarrier and near-barrier region (E_c.m. ranging from 9.7 to 13.4 MeV) using the ISAC facility at TRIUMF. γ-ray spectroscopy of the irradiated target foils along with β counting of the chemically separated Ge and As evaporation residues were used to measure the fusion cross sections. Statistical model calculations were used to correct for the yields of any unobserved nuclei. The observed fusion excitation function shows significant subbarrier fusion enhancement with a large deduced value of the fusion radius, R_B=12.1±1.0 fm. Coupled-channels calculations do not account for the observed subbarrier enhancement. The implications of this finding for understanding the fusion of ¹¹Li are discussed

[en] The p(¹¹Li,⁹Li)t reaction has been studied for the first time at an incident energy of 3A MeV at the new ISAC-2 facility at TRIUMF. An active target detector MAYA, built at GANIL, was used for the measurement. The differential cross sections have been determined for transitions to the ⁹Li ground and first excited states in a wide range of scattering angles. Multistep transfer calculations using different ¹¹Li model wave functions show that wave functions with strong correlations between the halo neutrons are the most successful in reproducing the observation