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The electronic and vibrational properties of TiS2, ZrS2, and HfS2have been studied using dispersion-corrected hybrid density functional methods. The periodic trends in electronic band structures, electronic transport coefficients, IR and Raman spectra, and phonon dispersion relations were investigated. Comparison to the available experimental data shows that the applied DFT methodology is suitable for the investigation of the layered transition metal dichalcogenide materials with weak interlayer van der Waals interactions. The choice of damping function in the D3 dispersion correction proved to have a surprisingly large effect. Systematic investigation of the periodic trends within group 4 disulfides reveals that TiS2shows many differences to ZrS2and HfS2due to the more covalent M–S bonding in TiS2. ZrS2and HfS2mainly show differences for properties where the atomic mass plays a role. All three compounds show similar Seebeck coefficients but clear differences in the relative electrical conductivity of cross- and in-plane directions. The transport and vibrational properties of thin TiS2single crystals were also investigated experimentally.

The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on the experience of the qualified staff or using data from reference books. The optimal dressing parameters, which are only valid for the particular methods and dressing and grinding conditions, are also used. The paper presents a methodology for optimization of the dressing parameters in cylindrical grinding. The generalized utility function has been chosen as an optimization parameter. It is a complex indicator determining the economic, dynamic and manufacturing characteristics of the grinding process. The developed methodology is implemented for the dressing of aluminium oxide grinding wheels by using experimental diamond roller dressers with different grit sizes made of medium- and high-strength synthetic diamonds type ??32 and ??80. To solve the optimization problem, a model of the generalized utility function is created which reflects the complex impact of dressing parameters. The model is built based on the results from the conducted complex study and modeling of the grinding wheel lifetime, cutting ability, production rate and cutting forces during grinding. They are closely related to the dressing conditions (dressing speed ratio, radial in-feed of the diamond roller dresser and dress-out time), the diamond roller dresser grit size/grinding wheel grit size ratio, the type of synthetic diamonds and the direction of dressing. Some dressing parameters are determined for which the generalized utility function has a maximum and which guarantee an optimum combination of the following: the lifetime and cutting ability of the abrasive wheels, the tangential cutting force magnitude and the production rate of the grinding process. The results obtained prove the possibility of control and optimization of grinding by selecting particular dressing parameters.

AbstractA precise and accurate knowledge of the characteristics of three-dimensional micro-objects such as inertial confinement fusion (ICF) targets and laser-produced plasmas is required to analyze the results of laser fusion experiments. Significant advances have been made in the development of tomographic information-processing methods for application to ICF target characterization. Topics discussed include (a) new high-resolution algorithm obtained by symmetrizing a basic filtered backprojection algorithm, (b) algorithms for threshold target characterization, (c) new approach to micro-object scanning based on quasi-uniform geometry, (d) ICF target preparation for tomographic characterization.