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 quantity w^N(r) = ( 1/ k^2 T_el)[partial n(r, T_el) / partial T_el]_(v(r),N) is introduced as a convenient measure of the local isoelectronic reactivity of surfaces. It characterizes the local polarizability of the surface and it can be calculated easily. The quantity w^N(r) supplements the charge transfer reactiv…
Additives Biodegradable Polymers Biomaterials for the Body Biomimetic Materials Biosensors Blends Block Copolymers Block Copolymer Micelles Comb-like Polymers Commercial Resins, Plastics, Elastomers Composites Compatibilizers Conducting Polymers Contact Lens Materials Controlled Release Dendrictic Polymers Dendrimers…
What electronic structure provides the largest figure of merit for thermoelectric materials? To answer that question, we write the electrical conductivity, thermopower, and thermal conductivity as integrals of a single function, the transport distribution. Then we derive the mathematical function for the transport dis…
Introduction History of the Invention and Development of the Polyimides, C. E. Sroog Synthesis Synthesis of Polyimides, Tohru Takekoshi Synthesis of Polyamideimides, Yoshio Imai Synthesis of Fluorinated Polyimides, Shigekuni Sasaki and Shiro Nishi Photosensitive Polyimides, Molecular Design and Synthesis, Toshihiko Om…
The well-known phase transition from InSb-IV to InSb-III at $\ensuremath{\sim}10\mathrm{GPa}$ has been studied using angle-dispersive powder-diffraction techniques. It is shown that the transition proceeds through a previously undetected intermediate phase, and that InSb-III is in fact identical with InSb-II. The appa…
A systematic study of the defects in ZnO has been performed. The two commonly observed levels (L1, L2), located at around 0.15 and 0.24 eV under the conduction band, have been identified as native defects. The deep level transient spectroscopy depth profiling technique is applied on multilayer-chip-type ZnO varistors…
The photoluminescence excitation technique is used to monitor the absorption characteristics of Si nanocrystals. Contributions from different critical points are identified, and their shift with reduced size is deduced. The enhancement of the oscillator strength of the indirect optical transitions due to the confineme…
The microstructure of filtered cathodic vacuum arc deposited tetrahedral amorphous carbon films is studied as a function of ion energy. An optimum energy window in the density and C–C sp3 content at an ion energy of ∼90 eV observed in this study. It is shown that the density of the amorphous carbon films are closely r…
We use inelastic neutron scattering to measure the spin wave dispersion throughout the Brillouin zone of the double-exchange ferromagnet L${\mathrm{a}}_{0.7}$P${\mathrm{b}}_{0.3}$Mn${\mathrm{O}}_{3}$. Magnons with energies as high as 95 meV are directly observed and an unexpectedly simple Heisenberg Hamiltonian, with…
States of charge carriers in transition metal compounds with low-frequency zero-spin - nonzero-spin transitions (e.g. some Co compounds) are investigated. Such transitions indicate the appearance of magnetic excitons on the transition metal ions. Charge carriers interact strongly with the excitons via exchange forces.…
The localization of low-frequency vibrational modes in amorphous solids can be determined from incoherent neutron scattering. Time-of-flight data from polystyrene and polybutadiene show a localization of the boson peak modes to about ten monomers.
The Escherichia coli pdxC(serC) gene codes for a transaminase (EC 2.6.1.52). The gene is involved in both pyridoxine (vitamin B6) and serine biosynthesis and was overexpressed as a MalE/PdxC(SerC) fusion protein. The fusion protein was purified by affinity chromatography on an amylose resin and hydrolyzed in the prese…
A simple model is presented to describe the phase behavior in binary mixtures of a flexible polymer and a liquid crystal. By using the incompressible approximation to the Onsager theory which combined both the excluded volume interactions between the liquid crystals and the attractive interaction due to the alignment…
Nanocrystallite size distribution and structural properties in alternating hydrogenated nanocrystalline silicon/amorphous silicon multilayers were investigated by means of Raman scattering. The obtained Raman spectra show a broad peak at ∼480 cm−1 from amorphous Si and some small peaks superposed on the broad peak. Ac…
By dynamic light scattering we have studied concentrated suspensions of ``hard-sphere'' colloidal particles in their equilibrium and metastable fluid states. We have found a simple, as yet unexplained, scaling procedure which collapses the measured intermediate scattering functions describing structural relaxation and…
Near-edge x-ray absorption fine structure (NEXAFS) measurements were performed on a variety of carbon materials, covering a range of hybrid bonding character from pure sp3 type to pure sp2 type. Diamond, chemical vapor deposited (CVD) diamond films of varying quality. Diamond-like carbon (DLC) films, and graphite were…
The local atomic structure of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ ( $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.12,$ 0.21, and 0.25) has been studied using pair-distribution-function analysis of neutron powder-diffraction data. A change is seen in the local structure which…
The reliability of the continuous transformations of origin of the current density method, which makes the transverse paramagnetic current vanish (CTOCD-PZ), for the prediction of nearly gauge-origin independent molecular magnetic susceptibility and gauge-origin independent nuclear magnetic shielding, is proved on the…
For nematic liquid crystals, we study the local stability of a radial hedgehog against biaxial perturbations. Our analysis employs the Landau - de Gennes functional to describe the free energy stored in a ball, whose radius is a parameter of the model. We find that a radial hedgehog may be either unstable or metastabl…
一様気流中におかれた橋梁断面に作用する動的空気力は桁の状態量 (速度, 変位) で表すことが多い. そのために動的空気力係数は風速, 振動数の関数となり, 周波数領域の解析を強いられる欠点がある. 本研究では, 拡張変数を導入して定数系の微分方提式で空気力を表す有理関数近似法の橋梁断面への適用を検討している. (1) 最小二乗法と最小状態量法を適用し. 後者の方が拡張変数の数が少なくてすむこと, (2) 翼形断面の場合は, 拡張変数が1つ, 偏平箱桁では2つ, トラス断面では3つ程度導入すれば精度よく動的空気力を表現でき, フラッター限界風速も精度よく予測できることを明らかにしている.