Materials Literature
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In the past decade macromolecular crystallography has undergone major advances in crystallization, data collection by synchrotron X-ray sources and area detectors, and data analysis by high performance computers and new computational techniques. In addition, recombinant gene technology in many cases allows the express…
The primary functional role of collagen is as a supporting tissue and it is now well established that the aggregated forms of the collagen monomers are stabilized to provide mechanical strength by a series of intermolecular crosslinks. These links are formed by oxidative deamination of the ε-amino group of the single…
Abstract The new trihydrate diphosphate, MnNH 4 NaP 2 O 7 ·3H 2 O, were synthesized and investigated by X‐ray diffraction and vibrational spectroscopy. Single crystal structure has been obtained using 1361 reflections with a final R value of 0.0564. This salt crystallizes in the monoclinic system, space group Cc, with…
Through comparison with the high-resolution structure of Clostridium symbiosum glutamate dehydrogenase, the different substrate specificities of the homologous enzymes phenylalanine dehydrogenase and leucine dehydrogenase were attributed to two residues, glycine 124 and leucine 307, in Bacillus sphaericus phenylalanin…
We present ab initio studies of $2\ifmmode\times\else\texttimes\fi{}1$ reconstructions of the diamond, Si, and Ge(113) surfaces. For all group-IV elements tetramers stabilize the (113) surface due to the tendency for opening of a surface-state gap. In the case of diamond, the symmetric tetramer structure with semicond…
Ni 81 Fe 19 was sputter deposited onto Si single-crystal wafers which had the native oxide layer intact. Dc hysteresis loops were measured using the magneto-optic Kerr effect, and anisotropy fields determined from the susceptibility. Saturation magnetostriction constants were deduced from the change in anisotropy fiel…
The incorporation of trans -cyclohexylene (C-ring) groups into the main chains of glassy polymers increases polymer chain dynamics. With the increase in trans-C-ring content in the main chain, both the coefficient of thermal expansion (CTE) of bulk specimens and the CTE of nanosized holes in these glasses increase. Tr…
We summarize our correlated scanning tunnelling microscopy and optical spectroscopy investigations of the electronic level structure and single-electron charging effects in CdSe quantum rods. Both optical and tunnelling spectra show that the level structure depends primarily on rod diameter and not on length. With inc…
A new approach to introduce polymers to cellulosic materials was developed by using the ability of a cellulose-binding module-Candida antarctica lipase B conjugate to catalyze ring-opening polymerization of epsilon-caprolactone in close proximity to cellulose fiber surfaces. The epsilon-caprolactone was introduced to…
Imidazole glycerol-phosphate dehydratase (IGPD) catalyzes the sixth step of histidine biosynthesis. The enzyme is of fundamental biochemical interest, because it catalyzes removal of a non-acidic hydrogen atom in the dehydration reaction. It is also a potential target for development of herbicides. IGPD is a metalloen…
Triangular Au and disk-shaped Au−Cu alloy nanocrystals have been generated in thin SiO 2 film matrixes, by sol−gel spin-coating followed by annealing at 800 °C in 10%H 2 −90%Ar. Transmission electron microscope images confirm the shapes of the embedded nanocrystals. X-ray diffraction patterns reveal that the Au and Au…
The presence of hydrogen in zinc oxide gives rise to n-type conductivity. Hydrogen effusion measurements performed on single-crystal ZnO and sputtered ZnO films directly reveal H concentrations of about $5.2\ifmmode\times\else\texttimes\fi{}{10}^{16}{\mathrm{cm}}^{\ensuremath{-}3}$ and up to $3.0\ifmmode\times\else\te…
Abstract A simple force constant model is described and applied to the vibrations of the layered molecular crystal of arsenic triiodide. The model uses nine adjustable parameters (three intramolecular and six intermolecular) to calculate the wavenumbers of 14 optical normal modes, and good agreement with observed Rama…
Crystallographic models are built by interpretation of an experimental image, the electron density map. This map is generally calculated from amplitudes measured experimentally and phases obtained with the multiple isomorphous replacement method. This method has poor precision, generating errors in the phases and ther…
In the past, the principal techniques of choice for analyzing tissue for various inorganic atomic species have been colometric and via atomic absorption spectrophotometry ( 1 ). Although both methods can be accurate and precise when performed in the same laboratory, there are disadvantages, which include interlaborato…
In an attempt to improve the field emission (FE) characteristics of carbon nanotubes (CNTs), we have performed a first-principles study on MgO-coated CNTs. A MgO slab covering a CNT tip under a strong electric field shows dielectric screening behaviours with applied electric fields up to 0.3 V Å −1 and the effective d…
LaInO(3), a promising ion conductor for a holistic solid oxide fuel cell, was synthesized by a solid-state reaction method. The structure was refined by the Rietveld method using X-ray powder diffraction data. The structure of LaInO(3) is distorted by the in-phase and antiphase tilting of oxygen octahedra in the a(+)b…
Epitaxial Prussian blue (PB) films are deposited electrochemically onto a Au(110) substrate. High-resolution X-ray diffraction shows that the PB films have a [111] out-of-plane orientation. The very large lattice mismatch of 148% is reduced to about 1% by the formation of (1 x 2)PB(111)[onemacr;10]//(6 x 5)Au(110)[one…
${\mathrm{E}\mathrm{r}}_{5}{\mathrm{S}\mathrm{i}}_{4}$ is a member of the ${R}_{5}({\mathrm{S}\mathrm{i}}_{4\ensuremath{-}x}{\mathrm{G}\mathrm{e}}_{x})$ family of alloys, where $R=\mathrm{r}\mathrm{a}\mathrm{r}\mathrm{e}$ earth metal. Many of these compounds display a strong coupling between the magnetic and crystal l…
We have used a kinetic model to investigate the influence of changing the pressure (0.1–0.8 Torr) and power (100–300 W) on the non-equilibrium plasma chemistry of RF (13.56 MHz) produced C 2 H 2 (1%)/H 2 /Ar plasmas of interest for the synthesis of nanodiamond thin films. We found that the concentrations of the specie…