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 nucleation event in protein crystallization is a part of the process that is poorly controlled. It is generally accepted that the protein should be in the metastable phase for crystal growth, but for nucleation higher levels of saturation are needed. Formation of nuclei in bulk solvent requires interaction of prot…
The geometries of neutral and charged carbon single-walled nanotubes (SWNTs) have been calculated using density functional theory. Periodic boundary conditions, a plane wave basis, and ultrasoft pseudopotentials are used in the generalized gradient approximation for isolated SWNTs with diameters of up to 20 and 12.5 Å…
A systematic experimental study of polymer-induced changes of the collective structure of model hard-sphere nanocolloids in the fluid and gel states has been carried out using ultra-small-angle x-ray scattering. The focus is on small, non-adsorbing polymer depletants where a direct transition from the homogeneous flui…
The effects of sulfur on the adhesion of ${\mathrm{N}\mathrm{i}/\mathrm{A}\mathrm{l}}_{2}{\mathrm{O}}_{3}$ interfaces are determined from first principles. The interfacial bonding is analyzed in terms of its ionic, covalent, and metallic components as well as its local electron orbital symmetries. The results reveal t…
The ET dynamics of a series of donor-spacer-acceptor (D-Sp-A) systems featuring (porphinato)zinc(II), (aryl)ethynyl bridge, and arene diimide units were investigated by pump-probe transient absorption spectroscopy. Analysis of these data within the context of the Marcus-Levich-Jortner equation suggests that the pi-con…
We report x-ray magnetic linear dichroism (XMLD) measurements at the Fe ${L}_{2,3}$ absorption edges of thin antiferromagnetic (AFM) ${\mathrm{LaFeO}}_{3}$ films grown epitaxially on ${\mathrm{SrTiO}}_{3}$ (100) and (110) substrates and a stepped (100) substrate with a 2\ifmmode^\circ\else\textdegree\fi{} miscut. The…
High-frequency and -field electron paramagnetic resonance (HFEPR) spectroscopy of a classical coordination complex, Mn(acac)(3) (Hacac = 2,4-pentanedione), has been performed on both solid powder and frozen solution (in CH(2)Cl(2)/toluene, 3:2 v/v) samples. Parallel mode detection X-band EPR spectra exhibiting resolve…
A new method and the software program BEST for optimal planning of X-ray data collection from protein crystals using the rotation method are presented. From one or a few initial diffraction images, BEST estimates the statistical characteristics of the data set for different combinations of data-collection parameters a…
An in situ x-ray diffraction experiment has been performed on phosphorus to characterize the liquid-liquid transition which occurs at high temperature and pressure. The transition line has been measured over an extended temperature range up to 2200 degrees C at 0.3 GPa. From the shape of this line, a thermodynamic cha…
Two oxygen species, which are constituents of the active centers for ethylene epoxidation over silver, have been characterized by a number of physical methods sensitive to adsorbate electronic structure such as x-ray photoelectron, ultraviolet photoelectron, Auger, and x-ray-absorption near-edge structure spectroscopy…
Dye doping is a promising way to increase the spectral purity of polymer light-emitting diodes (LEDs). Here we analyze the frequency and field dependence of the complex admittance of Al-Ba-PPV-PEDOT-ITO LEDs with and without dye. We compare the charge carrier mobilities of pristine and dye-doped double-carrier and hol…
The asymptotic analysis of the radiation pattern of a classical dipole in a photonic crystal possessing an incomplete photonic bandgap is presented. The far-field radiation pattern demonstrates a strong modification with respect to the dipole radiation pattern in vacuum. Radiated power is suppressed in the direction o…
The second order (in time) Schrodinger equation is proposed. The additional term (in comparison to Schrodinger equation) describes the interaction of particles with vacuum filled with virtual particle-antiparticle pairs (zitterbewegung). Key words: Schrodinger equation; Nanoscience; Zitterbewegung.
In this paper the Boltzmann transport equation for thermal processes induced by ultra-short laser pulses is formulated and solved. For thermal process where the duration of the laser pulse (femtoseconds - attoseconds) is shorter than the relaxation time, the solution of Boltzmann equation differs from the solution of…
The morphological evolution of the inorganic crystals (Ba(NO 3 ) 2, NH 4 Cl, H 3 BO 3, and K 2 Cr 2 O 7 ) was demonstrated in various kinds of organic gel media (agar, gelatin, pectin, and poly (vinyl alcohol)). As the gel density increased, the morphology grown in the gel matrix remarkably changed from polyhedral sin…
A new approach to analyzing macromolecular single-crystal X-ray diffraction intensity statistics is presented. Instead of considering reflections in resolution shells, differences between local pairs of reflection intensities are taken and normalized separately. When the two reflections to be compared (having intensit…
The formation of nanostructured materials through the assembly of nanocrystals is described, focusing in particular on silica and other metal oxide coated core particles. The preparation and optical characterization of core−shell materials are reviewed, and some of the unique properties of core−shell materials are pre…
Data available on the fd-transition energies of Ce 3+ in inorganic compounds are compared with those of Eu 2+ in the same compounds. Despite differing charge compensating defects, clear correlation was found. The redshift of absorption, the Stokes shift of emission, the centroid shift of the 5d configuration and the t…
Performances of LaCo x Fe 1-x O 3 perovskites as catalysts in dry reforming of ethane have been studied. Depending on x, the crystalline structure of the perovskite can be either orthorhombic or rhombohedral. The catalytic activity of the perovskite is tightly linked to its structure. If x ≤ 0.5 the reducing catalytic…
We theoretically investigate the modulation of carrier mobility in quasi-one dimensional organic crystals that consist of linear chains of conducting molecules. Two major electron-phonon interaction mechanisms are included in our model. It is shown that under certain conditions, the interplay of these two mechanisms m…