Materials Literature
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We investigate the minimal field strength in precessional magnetization switching using the Landau-Lifshitz-Gilbert equation in under-critically damped systems. It is shown that precessional switching occurs when localized trajectories in phase space become unlocalized upon application of field pulses. By studying the…
We have studied the shock-induced phase transition from fullerite to a dense amorphous carbon phase by tight-binding molecular dynamics. For increasing hydrostatic pressures P, the C60-cages are found to polymerise at P<10 GPa, to break at P~40 GPa and to slowly collapse further at P>60 GPa. By contrast, in the presen…
We calculate the frequency-dependent mesoscopic acoustic phonon transmission probability through the abrupt junction between a semi-infinite, one-dimensional cylindrical quantum wire and a three-dimensional bulk insulator, using a perturbative technique that is valid at low frequency. The system is described using ela…
The interaction potential of a $\mathrm{Li}$ atom with a graphene layer is calculated using the local density approximation to the density functional theory. Two configurations corresponding to different separations between $\mathrm{Li}$ in neighboring supercells were considered to determine the effect of $\mathrm{Li}…
The polymorphism of the simple amino acid glycine has been known for almost a century. It is also known that in aqueous solutions, at the isoelectric point (pI 5.9), the metastable alpha polymorph crystallizes, while the stable gamma form of glycine only nucleates at high and low pH. Despite the importance of understa…
Thermoelectric power, electrical conductivity, and high field Hall effect were studied over a broad temperature range in ferromagnetic Ga(1-x)Mn(x)As epitaxial layers (0.01570 K) the thermoelectric power in GaMnAs linearly increases with increasing temperature. That indicates the presence of a degenerate hole gas with…
We present results of an ultraviolet photoemission spectroscopy study of artificially synthesized poly(dA)-poly(dT) DNA molecules on $p$-type Si substrates. For comparison, we also present the electronic density of states (DOS) calculated using an \emph{ab initio} tight-binding method based on density-functional theor…
Hydrothermal reaction of CoCl2 with the potassium salt of pyridine-2,3-dicarboxylic acid and excess base yields [Co3(NC5H3(CO2)2-2,5)2(mu3-OH)2(OH2)2], which has a three-dimensional structure based on hydroxide-bridged triangular chains. The magnetic behavior of this compound shows the presence of three distinct regio…
Single wall carbon nanotube films (bucky paper ) have been prepared using aqueous dispersions containing 0, 3, 6, and 10 M nitric acid. With increasing nitric acid concentration, film tensile strength increased from 10 to 74 MPa, tensile modulus from 0.8 to 5.0 GPa, while in-plane dc electrical conductivity decreased…
We demonstrate that the magnetic properties of diluted magnetic semiconductors are dominated by short ranged interatomic exchange interactions that have a strong directional dependence. By combining first principles calculations of interatomic exchange interactions with a classical Heisenberg model and Monte Carlo sim…
The particle dynamics in a liquid exhibits a transient spatial distribution of dynamic heterogeneities. The relationship between this kinetic structure and the underlying particle configuration remains an outstanding problem. In this Letter, we present a general simulation technique for identifying the features of the…
A series of monomeric amide or aryloxide complexes of the form LCaX, where L = CH[CMeNC(6)H(3)-2,6-](2), CH[CMeNC(6)H(4)-2-OMe](2), a bulky tris-pyrazolyl borate, Tp(iPr) or Tp(tBu) or 9-BBN-pz(2) and X = N(SiMe(3))(2) or OC(6)H(3)-2,6-, has been prepared and characterized and investigated in the ring-opening polymeri…
A strong fluorescence emission was observed from different kinds of dendrimers under acidic condition. There was a remarkable difference in fluorescence properties between second and fourth generation NH2-terminated poly(amido amine) dendrimers. It can be assumed that the backbone of the dendrimer played the key role…
The concept that proteins exist in numerous different conformations or conformational substates, described by an energy landscape, is now accepted, but the dynamics is incompletely explored. We have previously shown that large-scale protein motions, such as the exit of a ligand from the protein interior, follow the di…
3'-Aminoglycoside kinase type IIIa [APH(3')-IIIa] catalyzes the transfer of gamma-phosphate from ATP to the 3'-hydroxyl of many aminoglycoside antibiotics, abolishing their bactericidal effects. Despite very low sequence identity, APH(3')-IIIa and eukaryotic protein kinases share structural and functional similarities…
Dutch elm disease fungus Ophiostoma novo-ulmi contains a hydrolase activity which catalyses the resolution of racemic ethyl naproxen to the corresponding acid. The recombinant enzyme has been crystallized by the vapour-diffusion method in two crystal forms. The crystals of the first form belong to space group P2(1)2(1…
Brillouin light scattering experiments were carried out on porous silicon layers fabricated from [111]-oriented p-type crystalline silicon substrates with resistivity 0.01 Ω cm. The thickness and porosity of the layers ranged from 1.6 to 11.40 µm and 0.25 to 0.40, respectively. The only Brillouin peaks evident in the…
The superconductor $\mathrm{Mg}\mathrm{C}{\mathrm{Ni}}_{3}$ has been chemically doped by partial substitution of Ru for Ni in the solid solution $\mathrm{Mg}\mathrm{C}{\mathrm{Ni}}_{3\ensuremath{-}x}{\mathrm{Ru}}_{x}$ for $0<x<0.5$. Magnetic and specific heat measurements show that the Sommerfeld parameter $({\e…
Succinyl-CoA:3-ketoacid CoA transferase (SCOT; EC 2.8.3.5) activates the acetoacetate in ketone bodies by transferring the CoA group from succinyl-CoA to acetoacetate to produce acetoacetyl-CoA and succinate. In the reaction, a glutamate residue at the active site of the enzyme forms a thioester bond with CoA and in t…
The crystal structure of Acetobacter aceti PurE was determined to a resolution of 1.55 A and is compared with the known structures of the class I PurEs from a mesophile, Escherichia coli, and a thermophile, Thermotoga maritima. Analyses of the general factors that increase protein stability are examined as potential e…