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。
The order−disorder transition temperature ( T ODT ) of symmetric styrene−isoprene diblock copolymers (AB) and its hetero-four-arm star analog (A 2 B 2 ) was measured using dynamic mechanical spectroscopy and small-angle X-ray scattering (SAXS). Care was taken to ensure that the arm molecular weights of both AB and A 2…
An analysis of the ligand field stabilization energy which makes allowance for the nephelauxetic effect is shown to give satisfactory results when applied to the hydration enthalpies of the hexaaqua 3+ complexes of the first transition series. The contribution from the nephelauxetic effect is substantial, and the base…
Intense visible upconversion luminescence is observed in a Re(4+)-doped low-phonon host material, Cs(2)ZrCl(6), with excitation in the near-infrared. The upconversion excitation wavelength, temperature, power, and time dependence is studied using variable-temperature absorption and luminescence spectroscopies, and mod…
Despite the great experimental effort carried out over the past years by means of different techniques, the segmental dynamics in the model blend system poly(vinylethylene)/polyisoprene (PVE/PI) is still a topic of strong debate. One of the most controversial questions is the possibility of a bimodal distribution of s…
Many biological processes, such as transmembrane signaling and pathogen-host interactions, are initiated by a protein recognizing a specific pattern of binding sites on part of a membrane or cell surface. By recognition, we imply that the polymer quickly finds and then adsorbs strongly on the pattern-matched region an…
Foreword. Preface. List of Contributors. VOLUME 1. Synthetic Methods. 1 Synthetic Methods for Semiconducting Polymers (Alberto Bolognesi and Maria Cecilia Pasini). 1.1 Introduction and Overview. 1.2 Synthetic Pathways for PA. 1.3 Conjugated Polymers by Step-Growth Polymerizations. 1.4 Block Copolymers. 1.5 Towards Aut…
An extremely easy method for accurately calculating the adiabatic connection of density functional theory is presented, and its accuracy tested on both Hooke's atom and the He atom. The method is easy because calculations are needed only for different values of parameters in the external potential, which can be achiev…
We present a near-field optical technique for second harmonic imaging using bare tapered optical fiber tip illuminated with femtosecond laser pulses. Enhancement of electric field at the tip of the fiber results in enhanced second harmonic generation (SHG) from the sample region near the tip. This SH emission is colle…
Freezing of simple liquid metals and the relative stabilities of competing crystalline solids are investigated using thermodynamic perturbation theory, the interactions between ions being modeled by effective pair potentials derived from pseudopotential theory. The ionic free energy of the solid phase is calculated, t…
Unstable homoepitaxy on rough substrates is treated within a linear continuum theory. The time dependence of the surface width W(t) is governed by three length scales: The characteristic scale $l_0$ of the substrate roughness, the terrace size $l_D$ and the Ehrlich-Schwoebel length $l_{ES}$. If $l_{ES} \ll l_D$ (weak…
We investigate the formation of ripples on the surface of windblown sand based on the one-dimensional model of Nishimori and Ouchi [Phys. Rev. Lett. 71, 197 (1993)], which contains the processes of saltation and grain relaxation. We carry out a nonlinear analysis to determine the propagation speed of the restabilized…
Unstable homoepitaxy on rough substrates is treated within a linear continuum theory. The time dependence of the surface width $W(t)$ is governed by three length scales: The characteristic scale $l_0$ of the substrate roughness, the terrace size $l_D$ and the Ehrlich-Schwoebel length $l_{ES}$. If $l_{ES} \ll l_D$ (wea…
Colloidal silver sols of long-time stability are formed in the γ-irradiation of 1.0 × 10 -4 M AgClO 4 solutions, which also contain 0.3 M 2-propanol, 2.5 × 10 -2 M N 2 O, and sodium citrate in various concentrations. The reduction of Ag + in these solutions is brought about by the 1-hydroxyalkyl radical generated in t…
Linearly polarized light can produce an anisotropic surface corrugation in amorphous chalcogenide films of Ag–As–S. The corrugation resembles a mouth whisker consisting of narrow fringes which are parallel to the electric field of light and streaks which radiate from the illuminated spot to directions nearly perpendic…
We report on the interface quality and phonon-assisted tunneling in nanocrystalline Si (nc-Si)/amorphous SiO2 (a-SiO2) superlattices (SLs) prepared by magnetron sputtering and thermal crystallization of nanometer-thick a-Si layers. Phonon-assisted tunneling is observed in a bipolar nc-Si based structure, which confirm…
We show that β-phase boron–carbon–nitrogen (C2BN) structures energetically favor segregation into superlattices of alternating diamond and cubic boron nitride (cBN) layers. Local-density functional calculations of total energies using pseudopotential approximations and a plane-wave basis set of the β-C2BN systems with…
We have used a millimeter-wave magneto-optical technique to study the angle dependence of the high-frequency conductivity of the molecular superconductor $\ensuremath{\kappa}\ensuremath{-}(\mathrm{BEDT}\ensuremath{-}\mathrm{TTF}{)}_{2}\mathrm{Cu}(\mathrm{NCS}{)}_{2}$. The data strongly suggest that the superconducting…
X-ray-absorption near-edge structure (XANES) measurements have been performed for a variety of boron-doped and undoped diamond films at the C K edge using the sample drain current mode. The C K-edge XANES spectra of B-doped diamonds resemble that of the undoped diamond regardless of the B concentration, which suggests…
We demonstrate that particles confined to two dimensions (2D) and subjected to a one-dimensional (1D) periodic potential exhibit a rich phase diagram, with both ``locked floating solids'' and smectic phases. The resulting phases and phase transitions are studied as a function of temperature and potential strength. We…
We discuss the design, fabrication and optical performance of a broadband form-birefringent quarter-wave plate for the 3.5 to 5 aem wave-length region. Rigorous coupled wave analysis (RCWA) was used to design the requisite subwavelength grating for silicon substrates in ambient air. Fabricated samples yield a measured…