Materials Literature
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Using a large polymer chain cluster, we have examined entanglement densities of the polymer chains in the bulk and in the surface by molecular dynamics simulation. The entanglement density was measured by the interchain contact fraction (ICF), which was developed as a structural parameter of the entanglement. It was f…
A database with details of the geometry of metal sites in proteins has been set up. The data are derived from metalloprotein structures that are in the Protein Data Bank [PDB; Berman, Henrick, Nakamura & Markley (2006). Nucleic Acids Res. 35 , D301–D303] and have been determined at 2.5 Å resolution or better. The…
Silver nanocrystals with tetrahedral shapes and {111} faces have been synthesized by the light-driven growth method in an aqueous solution. The nanocrystals of T(d) symmetry were formed under the effect of tartrate and citrate as the structural-directing reagents at the appropriate stages of reaction. Further, the nan…
Ultralow thermal conductivity ($1.1\text{ }\text{ }\mathrm{W}/\mathrm{m}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{K}$, $1000\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$) in anion-deficient ${\mathrm{Ba}}_{2}R{\mathrm{AlO}}_{5}$ ($R=\mathrm{Dy}$, Er, Yb) compounds was reported. The low thermal conduct…
The dependences of the maximum and the half-width of near band-edge photoluminescence of semi-insulating undoped GaAs crystals at 77K on the concentration of background acceptor impurities and the level of excitation in the range from 3x1021 to 6x1022 quantum/(cm2/s) are investigated. The observed dependences are expl…
We present a set of criteria to optimize photodetectors based on n-type metal oxide nanowires and a comparison methodology capable of overcoming the present lack of systematic studies dealing with such devices. The response of photoconductors is enhanced following different fabrication strategies, such as diminishing…
We examine an intrinsic graphene connected to the phonon thermostat at temperature T under irradiation of thermal photons with temperature T_r, other than T. The distribution of nonequilibrium electron-hole pairs was obtained for the cases of low and high concentration of carriers. For the case when the interparticle…
We observe remarkably strong room temperature ferromagnetism (~1.5 Bohr Magneton/Mn) in optically transparent Mn(II)-doped indium tin oxide (ITO) films. The nanocrystalline films with average grain size 10-22 nm and thickness 150-350 nm are prepared by sol-gel coating technique on sodalime silica glass substrate. The…
During the past five years the low temperature heat capacity of simple semiconductors and insulators has received renewed attention. Of particular interest has been its dependence on isotopic masses and the effect of spin- orbit coupling in ab initio calculations. Here we concentrate on the lead chalcogenides PbS, PbS…
Abstract Water‐blown rigid polyurethane foam (PUF) with two different particle sizes (180 and 300 μm) of expandable graphite (EG) as a flame‐retardant additive were prepared, and the effects on the mechanical, morphological, water absorption, thermal conductivity, thermal, and flame‐retardant properties were studied.…
Second order Moeller-Plesset perturbation theory (MP2) at the complete basis set (CBS) limit and diffusion quantum Monte Carlo (DMC) are used to examine several low energy isomers of the water hexamer. Both approaches predict the so-called "prism" to be the lowest energy isomer, followed by "cage", "book", and "cyclic…
Customizable ligand exchange of gold nanorods (NRs) is described. NRs are synthesized with the cationic surfactant cetyltrimethylammonium bromide (CTAB) which is exchanged with thiolated ligands that enable suspension in buffer. Exchange is achieved by a two phase extraction. First, CTAB is removed from the NR-CTAB by…
Method developed by Sandalov and coworkers [Int. J. Quant. Chem. 94, 113 (2003)] is applied to inelastic transport in the case of strong correlations on the molecule, which is relatively weakly coupled to contacts. Ability of the approach to deal with the transport in the language of many-body molecular states as well…
Sr_4Cr_3O_9 is the n = 2 member of a family of quasi-one-dimensional compounds A_{n+2}T_{n+1}O_{3n+3} (A = Ca, Sr, or Ba, T = transition metal, and n = 1 to \infty) having a crystal structure which consists of chains of n TO_6 octahedra alternated by one TO_6 trigonal prism running along the c-axis. The chains are arr…
We analyze the effect of time dependent external field on non-Markovian migration described by the continuous time random walk (CTRW) approach. The rigorous method of treating the problem is proposed which is based on the Markovian representations of the CTRW approach and field modulation. The method is applied to the…
Biexcitons in strongly confined, colloidal CdSe quantum dots were investigated with excitonic state selectivity combined with 10 fs temporal precision. Within the first 50 fs, the first excited state of the biexciton was observed. By 100 ps, mixed character biexcitons were observed, comprised of a core exciton and a s…
An in situ study of the contact-free crystallization of calcium carbonate in acoustic levitated droplets is reported. The levitated droplet technique allows an in situ monitoring of the crystallization while avoiding any foreign phase boundaries that may influence the precipitation process by heterogeneous nucleation.…
We report the synthesis of uniform crystalline WO 3 nanorods and their assembly without any surfactants. WO 3 nanorods have been synthesized by using a facile hydrothermal process without employing lithium ions and sulfates. Transparent WO 3 nanorod film has been prepared by assembled coating of the as-synthesized WO…
A mixed-valence Co(II)/Co(III) heptanuclear wheel [Co(II)3Co(III)4(L)6(MeO)6] (LH2 = 1,1,1-trifluoro-7-hydroxy-4-methyl-5-aza-hept-3-en-2-one) has been synthesized and its crystal structure determined using single-crystal X-ray diffraction. The valence state of each cobalt ion was established by bond valence sum calcu…
A set of 41 metal-ligand bond distances in 25 third-row transition-metal complexes, for which precise structural data are known in the gas phase, is used to assess optimized and zero-point averaged geometries obtained from DFT computations with various exchange-correlation functionals and basis sets. For a given funct…