Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
We study the steady state properties of a 2D granular mixture in the presence of energy driving by employing simple analytical estimates and Direct Simulation Monte Carlo. We adopt two different driving mechanisms: a) a homogeneous heat bath with friction and b) a vibrating boundary (thermal or harmonic) in the presen…
A detailed Linear Combination of Atomic Orbitals (LCAO) tight-binding model is developed for the layered High-Temperature Superconductor cuprates. The band structure of these materials is described using a sigma-band Hamiltonian employing Cu4s, Cu3d_x^2-y^2, O2p_x and O2p_y atomic orbitals. The Fermi level and the sha…
We describe a method for computing the response of an insulator to a static, homogeneous electric field. It consists of iteratively minimizing an electric enthalpy functional expressed in terms of occupied Bloch-like states on a uniform grid of k points. The functional has equivalent local minima below a critical fiel…
We analyze particle velocity fluctuations in a simulated granular system subjected to homogeneous quasistatic shearing. We show that these fluctuations share the following scaling characteristics of fluid turbulence in spite of their different physical origins: 1) Scale-dependent probability distribution with non-Guas…
We study numerically the minimum energy path and energy barriers for dislocation nucleation in a two-dimensional atomistic model of strained epitaxial layers on a substrate with lattice misfit. Stress relaxation processes from coherent to incoherent states for different transition paths are determined using saddle poi…
Static and dynamic changes induced by adsorption of atomic hydrogen on the NiAl(110) lattice at 130 K have been examined as a function of adsorbate coverage. Adsorbed hydrogen exists in three distinct phases. At low coverages the hydrogen is itinerant because of quantum tunneling between sites and exhibits no observab…
The interaction between a magnetic thin film and a superconductor is studied. In particular, the equilibrium width of a Bloch wall is estimated with and without the superconductor. It is shown that the Bloch wall experiences a small shrinkage on cooling through the critical temperature of the superconductor. Furthermo…
A simple, efficient and accurate method for the estimation of crystal densities is of interest for different applications. By analysis of the Cambridge Structural Database (CSD) we derived an average atom volume method to estimate the cell volume for a given formula and Z value. This method extends the work of Mighell…
The formation of a Ag stabilized regular step lattice on vicinal Si(111) miscut towards [11-2] is reported. The step bunching characteristic of the clean surface is prevented by a single-domain Si(111)-(3x1)-Ag reconstruction. The nanostructured surface is used as a template for growing one-dimensional arrays of 1 nm…
The spin glasses are disordered and frustrated magnetic systems. They show aging phenomena which are also a characteristic feature of structural glasses, polymers, dielectrics, colloids, etc. Under a strong enough magnetic field variation, spin glasses can be "rejuvenated", in the same way as glasses under a high enou…
It has been observed that the van der Waals interaction can cause an extruded core of a multiwalled carbon nanotube (MWNT) to retract into the outer shells. In a previous report [Q. Zheng and Q. Jiang, Phys. Rev. Lett. $88,$ 045503 (2002)], the authors pointed out that the restoring force resulted from the excess van…
Abstract Polypropylene (PP) nanocomposites were prepared by melt intercalation in an intermeshing corotating twin‐screw extruder. The effect of molecular weight of PP‐MA (maleic anhydride‐ modified polypropylene) on clay dispersion and mechanical properties of nanocomposites was investigated. After injection molding,…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of the Lanthanides Using Pyrazolylborate LigandsNoémia Marques, Andrea Sella, and Josef TakatsView Author Information Departamento de Química, ITN, Estrada Nacional 10, P-2686-953, Sacavém Codex, Portugal; Christopher Ingold Laboratories, Department of Chemistry, U…
Spurred by the recent demonstrations of the size- and support-dependent reactivity of supported gold clusters, here we present results on the coadsorption of CO and O(2) on selected anionic gold clusters, Au(N)(-), in the gas phase. O(2) adsorbs in a binary (0,1) fashion as a one-electron acceptor on the Au(N)()(-) cl…
The disordered nature of glass-forming melts gives rise to non-Arrhenius and non-exponential behaviour of their dynamics. With respect to the microscopic details involved in the structural relaxation, these materials have remained an unsolved puzzle for over a century. The observation of spatial heterogeneity regardin…
The materials community in both science and industry use crystallographic data models on a daily basis to visualize, explain and predict the behavior of chemicals and materials. Access to reliable information on the structure of crystalline materials helps researchers concentrate experimental work in directions that o…
A transmission electron microscopy (TEM) study was made to investigate the mechanism of isothermal crystallization from melt for syndiotactic polypropylene (sPP) with a syndiotactic pentad fraction of 0.92. The TEM morphologies of RuO4-stained and ultrathin-sectioned specimens revealed a clear assignment of lamellar c…
Abstract Historically, polyaniline (PANI) had been considered an intractable material, but it can be dissolved in some solvents. Therefore, it could be processed into films or fibers. A process of preparing a blend of conductive fibers of PANI/poly‐ω‐aminoundecanoyle (PA11) is described in this paper. PANI in the emer…
We developed a specimen-drift-free energy-dispersive X-ray (EDX) mapping system in a scanning transmission electron microscope (STEM) to improve the sensitivity and spatial resolution of EDX elemental mapping images. The amount of specimen drift was analysed from two STEM images before and after specimen drift by usin…
A new method of protein crystallization based on a homologous Langmuir-Schaefer (LS) protein thin-film template proves to successfully stimulate crystal nucleation and growth of the four different proteins being studied, under different crystallization conditions including those failing to lead to crystal formation in…