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。
Abstract We investigated the tensile strength and modulus of ultrahigh‐strength polyethylene (UHSPE) fibers obtained by using the special two‐step‐drawing process of as‐spun fiber (ASFs) which were prepared by the so‐called gel‐spinning method. We have found that the higher the ASF's spinning speed is, the higher the…
A theoretical approach is developed to derive a hierarchy of mode-coupling equations for the dynamics of concentrated colloidal suspensions, which improves the prediction of the colloidal glass transition. Our derivation is based on a matrix formalism for stochastic dynamics and the resulting recursive expressions for…
The problem of homogenization, i.e. substantial reduction of the electrical size of the average lattice constant, of electromagnetic left-handed (LH), or more generally composite right/left-handed (CRLH) metamaterials (MTMs), is presented. The undesirable effects of an electrical very large structural unit cell are ex…
Different grades of stoichiometric and non‐stoichiometric dense magnesium aluminate spinel (MgAl 2 O 4 ) grains were prepared by a conventional double‐stage firing process using two types of alumina and four types of magnesia raw materials. The MgAl 2 O 4 spinel formation was found to be highly influenced by CaO and m…
It is often assumed that the viscoelastic properties of dense colloids are determined by the colloid volume fraction, the interaction potential, as well as the particle size distribution and shape. The dependence of the viscoelastic behavior of particle suspensions and gels on these parameters has been widely studied,…
Abstract Characterisation results from a single‐crystal CVD diamond detector are reported, which is under development for heavy‐ion particle identification and minimum‐ionizing particles timing in nuclear physics experiments. The charge collection efficiency is about 100%, never obtained from polycrystalline CVD‐diamo…
Metal nanohole arrays with straight holes of high aspect ratio have been fabricated using a new replication process based on the preparation of polymer pillars, both sides of which are supported and can therefore be maintained upright. These nanopillar arrays are demonstrated as negatives for the preparation of metal…
Density functional calculations are used to investigate the trends in the lattice instabilities of the perovskites, $\mathrm{Ba}\mathrm{Ti}{\mathrm{O}}_{3}$, $\mathrm{Pb}\mathrm{Ti}{\mathrm{O}}_{3}$, $\mathrm{Ba}\mathrm{Zr}{\mathrm{O}}_{3}$, and $\mathrm{Pb}\mathrm{Zr}{\mathrm{O}}_{3}$ with volume. A simple scheme for…
An amphiphilic liquid-crystalline diblock copolymer can be used to record both refractive-index and surface-relief holographic gratings upon irradiation by two coherent laser beams. The diffraction behavior of the gratings is controlled by nanoscale phase separation on annealing. Surface relief is enhanced by almost a…
Welded conducting polymer nanofibers (see Figure) with rapid electrochromic switching speeds have been prepared by electrospinning a soluble precursor polymer with pendant heterocycles into nanofibers which are subsequently crosslinked via solid-state oxidative crosslinking. The switching speeds between the oxidized a…
Recent experimental findings suggest that the bulk modulus of osmium is comparable to that of diamond. From first principles calculations we examine the compressibility of diamond, Os, OsC, OsN, and $\mathrm{Os}{\mathrm{O}}_{2}$ as well as cubic BN under pressure. We show that Os, OsC, and OsN in the hexagonal structu…
Amorphous CaCO3 (ACC) is stabilized by the presence of phytic acid, a natural inositol hexakisphosphate (IP6). Micrometer-sized hollow spheres of ACC have been obtained (see Figure). The spheres are stable for at least three months in solution, which is equivalent to that described for more complex special biopolymers…
A uniplanar transmission-line (TL) network has been loaded with lumped elements (chip or printed), enabling one to achieve a two-dimensional (2D) uniplanar negative-refractive-index (NRI) metamaterial. The metamaterial consists of a 2D array of unit cells, composed of TL sections connected in series and loaded in a sp…
We report on the effect of electron-phonon coupling on quantum transport in carbon nanotubes. The vibrational atomic displacements as well as the electron-phonon coupling strength are introduced through a time-dependent perturbation of the pi-electron Hamiltonian. The effect of dephasing on the Kubo conductance is stu…
First-principles calculations are used in order to investigate phonon anomalies in nonmagnetic and magnetic Heusler alloys. Phonon dispersions for several systems in their cubic $L{2}_{1}$ structure were obtained along the [110] direction. We consider compounds that exhibit phonon instabilities and compare them with t…
Charged pattern formation on the surfaces of self--assembled cylindrical micelles formed from oppositely charged heterogeneous molecules such as cationic and anionic peptide amphiphiles is investigated. The net incompatibility $χ$ among different components results in the formation of segregated domains, whose growth…
The use of magnetic nanowires as memory units is made possible by the exponential divergence of the characteristic time for magnetization reversal at low temperature, but the slow relaxation makes the manipulation of the frozen magnetic states difficult. We suggest that finite-size segments can show a fast switching i…
An unusually large magnetocaloric effect for the temperature region below 10 K is found for the Fe14 molecular nanomagnet. This is to large extent caused by its extremely large spin S ground state combined with an excess of entropy arising from the presence of low-lying excited S states. We also show that the highly s…
We study three regimes of the Mott transitions characterized by classical, marginally quantum, and quantum. In the classical regime, the quantum degeneracy temperature is lower than the critical temperature of the Mott transition ${T}_{c}$, below which the first-order transition occurs. The quantum regime describes th…
The definition of the fundamental quantity, the chemical potential, is badly confused in the literature: there are at least three distinct definitions in various books and papers. While they all give the same result in the thermodynamic limit, major differences between them can occur for finite systems, in anomalous c…