MPFEM Modeling on the Compaction of Al/SiC Composite Powders with Core/Shell Structure

Uniaxial die compaction of two-dimensional (2D) Al/SiC core/shell (core: SiC; shell: Al) composite powders with different initial packing structures was numerically reproduced using DEM-FEM coupled MPFEM modeling from particulate scale. The effects of external pressure, initial packing structure, and SiC content on the packing densification were systematically presented. Various macro and micro properties such as relative density and distribution, stress and distribution, particle rearrangement (e.g. sliding and rolling), deformation and mass transfer, and interfacial behavior within composite particles were characterized and analyzed. The results show that by properly controlling the initial packing structure, pressure, and SiC content, various anisotropic and isotropic Al/SiC particulate composites with high relative densities and uniform density/stress distributions can be obtained. At early stage of the compaction, the densification mechanism mainly lies in the particle rearrangement driven by the low interparticle forces. In addition to sliding, accompanied particle rolling also plays an important role. With the increase of the compaction pressure, the force network based on SiC cores leads to extrusion on Al shells between two cores, contributing to mass transfer and pore filling. During compaction, the debonding between the core and shell of each composite particle appears and then disappears gradually in the final compact

Tetra­kis(μ-naphthalene-1-acetato-1:2κ2 O:O′)bis­(naphthalene-1-acetato)-1κ2 O,O′;2κ2 O,O′-bis­(1,10-phenanthroline)-1κ2 N,N′;2κ2 N,N′-europium(III)samarium(III)

In the title compound, [EuSm(C12H9O2)6(C12H8N2)2], the metal site is statistically occupied (50:50) by Eu and Sm atoms, forming a centrosymmetric complex. The metal site is nine-coordinate, in a distorted monocapped square-anti­prismatic coordination geometry. Mol­ecules are linked into three chains by C—H⋯π interactions and C—H⋯O hydrogen bonds. The combination of these chains generates a three-dimensional framework structure. One of the bridging naphthalene-1-ace­tate ligands was found to be disordered over two sites; the site occupancies for the naphthylmethyl group refined to 0.628 (14) and 0.372 (14)

On the Analysis of Product Appropriateness Principles

The purpose of this study is to explore appropriateness of the various products presented in the market and the application of appropriateness principles to the product design. To obtain appropriateness principles, this study compares and analyzes a variety of products available in the market. After obtaining preliminary principles, many times convergence and analysis are operated for getting more accurate principles. Then, AHP method is used for evaluating importance of every appropriateness principles and appropriateness principles are obtained. And, the appropriateness principles are used to construct the design process of appropriateness product. Finally, some design cases are operated and appropriateness principles are evaluated for the products of design cases. The results of this study are obtained 10 appropriateness principles: freedom, demand, environmental protection, effectiveness, intuition, compliance, simplicity, optimal performance, simplicity, fault tolerance. And, weights of appropriateness principles get in this paper

4-Methyl-2-oxo-2,3-dihydro-1-benzopyran-7-yl benzene­sulfonate

The title compound, C16H12O5S, is a derivative of coumarin. The dihedral angle between the coumarin ring system and the phenyl ring is 65.9 (1)°. In the crystal structure, mol­ecules are linked by weak C—H⋯O hydrogen bonding to form molecular ribbons

Diaqua­bis(N,N′-dibenzyl­ethane-1,2-diamine-κ2 N,N′)nickel(II) dichloride N,N-dimethyl­formamide solvate

The asymmetric unit of the title complex, [Ni(C16H20N2)2(H2O)2]Cl2·C3H7NO, consists of two NiII atoms, each lying on an inversion center, two Cl anions, two N,N′-dibenzyl­ethane-1,2-diamine ligands, two coordinated water mol­ecules and one N,N-dimethyl­formamide solvent mol­ecule. Each NiII atom is six-coordinated in a distorted octa­hedral coordination geometry, with the equatorial plane formed by four N atoms and the axial positions occupied by two water mol­ecules. The complex mol­ecules are linked into a chain along [001] by N—H⋯Cl, N—H⋯O and O—H⋯Cl hydrogen bonds. The C atoms and H atoms of the solvent mol­ecule are disordered over two sites in a ratio of 0.52 (2):0.48 (2)