Materials Literature
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The available literature on the crystal structure of the metastable alumina polymorphs and their associated transitions is critically reviewed and summarized. All the metastable alumina structures have been identified as ordered or partially ordered cation arrays on the interstitial sites of an approximately close‐pac…
▪ Abstract The term bone refers to a family of materials, all of which are built up of mineralized collagen fibrils. They have highly complex structures, described in terms of up to 7 hierarchical levels of organization. These materials have evolved to fulfill a variety of mechanical functions, for which the structure…
The program POTATO, which was developed to model distorted perovskite structures, has been used to assess the stability of hypothetical compositions and guide the synthesis of new materials at high pressures and high temperatures. The initial result of this effort is the synthesis of two new perovskites, Ca 2 NdAgTi 4…
We introduce a concept for random tilings which, comprising the conventional one, is also applicable to tiling ensembles without height representation. In particular, we focus on the random tiling entropy as a function of the tile densities. In this context, and under rather mild assumptions, we prove a generalization…
We report an electrochemical, scanning probe microscopic, and Raman spectroscopic investigation of thin CdS films grown by electrochemical atomic layer epitaxy aimed at understanding the role played by the order of deposition on film quality. Using scanning tunneling microscopy (STM), we determine the atomic level str…
The growth rate of the hydroxyapatite (0001) face in pseudophysiological solution was measured directly for the first time by Moire phase shift interferometry. Common-path-type interferometry and a newly developed signal processor used for the phase shift technique enabled the precise and stable measurement of growth…
The amino-functionalized porphyrazines 1, 2, and 4 and norphthalocyanines 3 and 5, which were prepared via Linstead macrocyclization reactions of dinitrile precusors, were subject to UV-vis titrations in the presence of inorganic ions. These polydentate macrocycles are able to bind metal ions by the peripheral ligatin…
Axial ligation of nickel(II) 5,10,15,20-tetraphenylporphyrin (NiTPP) with pyrrolidine or piperidine has been investigated using X-ray crystallography, UV-visible spectroscopy, resonance Raman spectroscopy, and molecular mechanics (MM) calculations. By varying the pyrrolidine concentration in dichloromethane, distinct…
Recently, discrete sets of numbers, the -integers , have been proposed as numbering tools in quasicrystalline studies. Indeed, there exists a unique numeration system based on the irrational in which the -integers are all real numbers with no fractional part. These -integers appear to be quite appropriate for describi…
Measurements and theoretical calculations are reported for an interatomic multi-atom resonant photoemission (MARPE) effect that permits direct determination of near-neighbor atomic identities (atomic numbers). MARPE occurs when the photon energy is tuned to a core-level absorption edge of an atom neighboring the emitt…
Two distinctly different membrane proteins, which produced inclusion bodies in Escherichia coli, have been refolded to reconstitute properties appropriate to their native counterparts. The method employed utilises nickel chelating chromatography, where the solubilised inclusion bodies bind, refold and elute. Our aims…
A new family of oligopeptide-based bolaamphiphiles, glycylglycine- ( 1a − h ), glycylglycylglycine- ( 2a − b ), sarcosylsarcosine- ( 3 ), l -prolyl- l -proline- ( 4 ), glycylsarcosylsarcosine- ( 5 ), and glycyl- l -prolyl- l -proline ( 6 )-based bolaamphiphiles with a dicarboxylic headgroup at each end, has been synth…
The package fhi98PP allows one to generate norm-conserving pseudopotentials adapted to density-functional theory total-energy calculations for a multitude of elements throughout the periodic table, including first-row and transition metal elements. The package also facilitates a first assessment of the pseudopotential…
First-principles electronic-structure methods are used to study a structural model for Ag/Si(111)3x1 recently proposed on the basis of transmission electron diffraction data. The fully relaxed geometry for this model is far more energetically favorable than any previously proposed, partly due to the unusual formation…
The reductive condensation of a carbon-supported molecular cluster precursor, PtRu 5 C(CO) 16, into a bimetallic nanoparticle has been followed by using in situ extended X-ray absorption fine structure spectroscopy, temperature-programmed desorption, and scanning transmission electron microscopy. The data reveal that…
The precipitation polymerization of commercial divinylbenzene in acetonitrile containing up to 40 vol. % toluene or other cosolvents is shown to produce novel porous monodisperse poly(divinylbenzene) microspheres. These microspheres have diameters between 4 and 7 μm, total pore volumes of up to 0.52 cm3/g, and surface…
The thermodynamic properties of novolac type phenolic resin blended with poly(ethylene oxide) (PEO) were investigated by the Painter–Coleman association model (PCAM). Equilibrium constants and enthalpy corresponding to the interaction between phenolic and poly(ethylene oxide) were calculated from the Fourier transform…
We have studied the nonisothermal and isothermal crystallization kinetics of an aromatic thermotropic liquid crystalline polyimide synthesized from 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA) and 1,3-bis[4-(4′-aminophenoxy) cumyl] benzene (BACB) by means of differential scanning calorimetry (DSC). Polarized ligh…
Sorption, dilation, and diffusion behaviors were studied for the system of polysulfone/CO2 with regard to the effects of CO2 conditioning, i.e., exposure to high-pressure CO2. Concurrent measurements of solubility, dilation, and diffusivity were performed for polysulfone films before and after the conditioning at 25 a…
An ultrasonic shear wave reflection method was applied to study film formation and temperature dependence of the complex shear modulus (G*G′ + iG″) in different amorphous films made of aqueous dispersions of acrylic-type copolymers. The data are compared with dynamic-mechanical measurements in the low frequency range…