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First principle calculations were performed to investigate the structural, mechanical, electronic properties, and thermodynamic properties of three binary Mg–B compounds under pressure, by using the first principle method. The results implied that the structural parameters and the mechanical properties of the Mg–B compounds without pressure are well matched with the obtainable theoretically simulated values and experimental data. The obtained pressure–volume and energy–volume revealed that the three Mg–B compounds were mechanically stable, and the volume variation decreases with an increase in the boron content. The shear and volume deformation resistance indicated that the elastic constant Cij and bulk modulus B increased when the pressure increased up to 40 GPa, and that MgB7 had the strongest capacity to resist shear and volume deformation at zero pressure, which indicated the highest hardness. Meanwhile, MgB4 exhibited a ductility transformation behaviour at 30 GPa, and MgB2 and MgB7 displayed a brittle nature under all the considered pressure conditions. The anisotropy of the three Mg–B compounds under pressure were arranged as follows: MgB4 > MgB2 > MgB7. Moreover, the total density of states varied slightly and decreased with an increase in the pressure. The Debye temperature ΘD of the Mg–B compounds gradually increased with an increase in the pressure and the boron content. The temperature and pressure dependence of the heat capacity and the thermal expansion coefficient α were both obtained on the basis of Debye model under increased pressure from 0 to 40 GPa and increased temperatures. This paper brings a convenient understanding of the magnesium–boron alloys.

The structural properties, elastic anisotropy, electronic structures and work function of D022-type Al3TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al3Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D022-type Al3TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al3La is the strongest, while that of Al3Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D022-Al3Ta has an excellent strengthening effect.

The first-principles calculations have been performed to predict the effect of transition-elements substitution on mechanical properties and electronic structures of B2-AlCu compounds. The results show that Zn, Cd, La and Hg are preferred to replace Al atom, while other transition elements are preferred to replace Cu atom. Among the mechanically stable AlCu-TM compounds, the resistance of axial deformation is greater than that of shear deformation. According to Poisson's ratio and Pugh criteria, all compounds show ductility. The compounds of Al8Cu7Fe, Al8Cu7Tc and Al8Cu7Re exhibit excellent Young's modulus and Vickers hardness in fourth, fifth and sixth periods, respectively. The bulk moduli of all AlCu-TM compounds indicate a low degree of isotropic deviation, while the shear moduli have a large anisotropy. The analysis of the electronic structures of Al8Cu7Fe, Al8Cu7Tc and Al8Cu7Re demonstrates that metal bond and covalent bond are mixed, and the properties of covalent bond between TM and Cu are weak.

Translational and rotational diffusion coefficients of liquid water have been computed from molecular dynamics simulation with a recent polarizable potential at 298, 400, and 550 K at very high pressure. At 298 K, the model reproduces the initial increase and the occurrence of a maximum for the translational and rotational diffusion coefficients when the pressure increases. At 400 and 550 K, translational and rotational diffusion coefficients are found to monotonically decrease when pressure increases in the gigapascal range, with the translational coefficient decreasing faster than the rotational one. At 400 K, such an evolution of the rotational diffusion coefficient contrasts with quasielastic neutron scattering results predicting a near independence of the rotational diffusion with a pressure increase above ≃0.5 GPa. An interpretation is proposed to explain this discrepancy. The pressure dependence of the translation-rotation coupling is analyzed. The anisotropy of rotational diffusion is investigated by computing the rotational diffusion tensor in a molecular system of axes and the reorientational correlation times of rank 1 and rank 2 of the inertia axes and of the OH bond vector. Deviation of the simulation data with respect to the predictions of the isotropic Debye model of rotational diffusion are quantified and can be used to estimate experimental rotational diffusion coefficients from experimental reorientational correlation times.

The excellent comprehensive properties of Al-La binary alloy are mainly due to the stable distribution of Al-La intermetallic compounds in the microstructure. In this work, first-principle calculations have been performed to investigate the phase stability, elastic and electronic properties of eight binary Al-La intermetallic compounds. The results indicated that crystal parameters of Al-La compounds agree well with other experimental and calculated values. The calculated formation enthalpy and cohesion energies of these compounds are less than zero, which indicates that these Al-La binary compounds have good thermal stability. The result reveals that the cohesive energy of these Al-La intermetallic compounds in the binary system decreases with the increase of La content. Among these compounds, Al3La has the highest shear modulus and the strongest resistance to shear strain. The result indicates that the Al-La compounds in this study have an intrinsic sixth power correlation with the work function. It is found that Al11La3 is the most anisotropic in these Al-La binary compounds. The value at the Fermi level is not equal to zero, indicating that all these binary compounds have metal properties. Debye temperature calculation results show that Al3La has the strongest binding force between atoms of Al-La intermetallic compounds. Furthermore, the results show that these compounds have anisotropy of longitudinal and transverse sound velocity in different crystallographic directions.

Different Ni 1-D nanostructures were fabricated in various porous anodic alumina templates by electrodeposition, including Ni nanochains containing grains with diameters of 15 nm, Ni nanowires with diameters of 50 nm, and Ni nanotubes with outer diameters of 240 nm. The magnetic properties are strongly dependent on the morphology and size of Ni nanostructures. Ni nanochains have no obvious easy axis direction and present a very small coercivity. The easy axis of Ni nanowires is oriented parallel to the wire axis, and the effective magnetic anisotropy is mainly from shape anisotropy. For Ni nanotubes, easy axis is perpendicular to the tube axis, which is dominated by the magnetic dipole interaction. The angular dependence of the coercivity indicates that the weakly coupled nanoparticles within the Ni nanochains reverse their magnetization nearly independently, however, for Ni nanowires, magnetic reversal process is dominated by localized quasi-coherent nucleation mode, and Ni nanotubes show a complicated reversal behavior.

Anisotropy is important to the structure and application of nonwoven fabrics. The arrange ment of the fibers and their orientation distribution are related to the mechanical structure of the web. In this study, we used a doffer of the roller card accompanied by a random roller to produce nonwoven fabrics. Partial random fiber arrangement is obtained by transferring the fibers on the rollers. As a result, the ratios of tensile and tearing strengths of the random web are below 3.0 and above 0.5, respectively. We can use this novel random arrangement of fibers in webs to improve the anisotropy of nonwoven fabrics.

In this work, the effect of nanoparticle confinement on the magnetic relaxation of iron oxide (Fe3O4) nanoparticles (NP) was investigated by measuring the hyperthermia heating behavior in high frequency alternating magnetic field. Three different Fe3O4 nanoparticle systems having distinct nanoparticle configurations were studied in terms of magnetic hyperthermia heating rate and DC magnetization. All magnetic nanoparticle (MNP) systems were constructed using equivalent ~10nm diameter NP that were structured differently in terms of configuration, physical confinement, and interparticle spacing. The spatial confinement was achieved by embedding the Fe3O4 nanoparticles in the matrices of the polystyrene spheres of 100 nm, while the unconfined was the free Fe3O4 nanoparticles well-dispersed in the liquid via PAA surface coating. Assuming the identical core MNPs in each system, the heating behavior was analyzed in terms of particle freedom (or confinement), interparticle spacing, and magnetic coupling (or dipole-dipole interaction). DC magnetization data were correlated to the heating behavior with different material properties. Analysis of DC magnetization measurements showed deviation from classical Langevin behavior near saturation due to dipole interaction modification of the MNPs resulting in a high magnetic anisotropy. It was found that the Specific Absorption Rate (SAR) of the unconfined nanoparticle systems were significantly higher than those of confined (the MNPs embedded in the polystyrene matrix). This increase of SAR was found to be attributable to high Néel relaxation rate and hysteresis loss of the unconfined MNPs. It was also found that the dipole-dipole interactions can significantly reduce the global magnetic response of the MNPs and thereby decrease the SAR of the nanoparticle systems.

A sharp variation at some radial positions superimposed on a slow change in the profiles of the fluctuation levels, fluctuation-driven particle and energy fluxes, which is referred as spatial intermittency, is observed in the core plasma of the Keda Tokamak-5C (KT-5C) [World Survey of Activities in Controlled Fusion Research, Nuclear Fusion Special Supplement (International Atomic Energy Agency, Vienna, 1991), p. 190.]. The peaks in the profiles are located in the vicinity of low-q rational surfaces, and fluctuation spectra perpendicular to the magnetic field become more anisotropy there. The intermittency may be related to the radial variations in the nonlinear mode couplings near the low-q resonant surfaces.

Notecarin D (NotD) is a prothrombin (ProT) activator in the venom of the tiger snake, Notechis scutatus, and a factor Xa (FXa) homolog. NotD binds specifically to the FXa binding site expressed on factor V (FV) upon activation to factor Va (FVa) by thrombin. NotD active site-labeled with 5-fluorescein ([5F]FFR-NotD) binds FV and FVa with remarkably high affinity in the absence of phospholipids (K(D) 12 and ≤ 0.01 nm, respectively). In the presence of membranes, the affinity of [5F]FFR-NotD for FVa is similar, but increased ∼55-fold for FV. Binding of FXa active site-labeled with Oregon Green to FV and FVa in the presence of phospholipids is ∼5,000- and ∼80-fold weaker than [5F]FFR-NotD, respectively. NotD reports FVa and not FV binding by a 3-fold increase in tripeptide substrate hydrolysis, demonstrating allosteric regulation by FVa. The NotD·FVa·membrane complex activates ProT with K(m)((app)) similar to prothrombinase, and ∼85-fold weaker without membranes. Active site-blocked NotD exhibits potent anticoagulant activity in plasma thrombin generation assays, representing inhibition of productive prothrombinase assembly and possible disruption of FXa inhibition by the tissue factor pathway inhibitor. The results show that high affinity binding of NotD to FVa is membrane-independent, unlike the strict membrane dependence of FXa for high affinity FVa binding.

A one-pot colloidal reaction strategy was developed to synthesize asymmetric magnetic composite particles (AMCPs) with high anisotropy and magnetic content. The asymmetricity was established by having two portions of the particle composed of both polystyrene and silica, among which the latter was conjugated with magnetite nanoparticles. Phase separation was found to be critical in developing the asymmetric structure between the inorganic and polymer components during miniemulsion polymerization and the sol–gel reaction. Morphological control of the magnetic composite particles was achieved in a straightforward fashion by adjusting the processing parameters. These asymmetric nanomaterials with superparamagnetic and amphiphilic properties will have significant potential in biomedical applications.