Materials Literature
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A highly efficient and practical method for obtaining alpha,beta-epoxy ketones with high optical purities was developed. The chiral lanthanum complex self-organized in situ from lanthanum triisopropoxide, (R)-BINOL, triarylphosphine oxide, and alkyl hydroperoxide (1:1:1:1) was found to catalyze the epoxidation of alph…
The anisotropic OH stretching vibrational behavior of three birefringent garnet crystals with compositions close to the uvarovite-grossular binary from the locality Saranov (Ural Mountains, Russia) are investigated in detail by polarized IR micro-spectroscopy. These garnet samples exhibit low but significantly differe…
Matsubaraite, Sr 4 Ti 5 (Si 2 O 7 ) 2 O 8 , is a new member of the perrierite-chevkinite group found in the jadeitite from the Itoigawa-Ohmi district, central Japan. It is monoclinic, P 2 1 / a (pseudo C 2/ m ). a = 13.848(7), b = 5.626(2), c = 11.878(6) A, β = 114.19(4)°, V = 844 A 3 and Z = 2. The six strongest line…
By combining model-potential molecular-dynamics simulations and ab initio calculations we investigate the microscopic mechanism of silicon trapping by carbon substitutional defects ${(C}_{S}).$ We find that, upon silicon trapping, carbon is converted into an interstitial mobile complex ${(C}_{I})$ by an efficient exot…
Abstract A new triphenylamine‐containing aromatic dicarboxylic acid, N,N ′‐bis(4‐carboxyphenyl)‐ N,N ′‐diphenyl‐1,4‐phenylenediamine, was synthesized by the condensation of N,N ′‐diphenyl‐1,4‐phenylenediamine with 4‐fluorobenzonitrile, followed by the alkaline hydrolysis of the intermediate dinitrile compound. A serie…
Au nanocrystals spin-coated onto silicon from toluene form cellular networks. A quantitative statistical crystallography analysis shows that intercellular correlations drive the networks far from statistical equilibrium. Spin-coating from hexane does not produce cellular structure, yet a strong correlation is retained…
A study is presented of the self-assembly process that takes place during CTAB-templated silica film formation through in situ SAXS, interferometry and water titration investigations during evaporation associated with dip coating under various conditions. This work shows that the quantity of water present in the film…
The industrial use of ultraviolet (UV) and electron beam (EB) radiation is growing rapidly and now penetrates an ever-widening range of applications, including electronics, printing, packaging. Resources and references for seasoned professionals abound, but few effectively introduce the field to newcomers or provide f…
X-ray magnetic circular dichroism (XMCD) is an element-, site- and symmetry-selective spectroscopic technique that has the potential to provide quantitative information on site occupancies in ferri- and ferro-magnetic minerals. XMCD spectra derived from the Fe L2,3 absorption edge of a series of synthetic spinel ferri…
By suitably adapting a recent approach [A. Laio and M. Parrinello, PNAS, 99, 12562 (2002)] we develop a powerful molecular dynamics method for the study of pressure-induced structural transformations. We use the edges of the simulation cell as collective variables. In the space of these variables we define a metadynam…
We consider spin-lattice relaxation processes for electrons trapped in lateral Si quantum dots in a $[001]$ inversion layer. Such dots are characterized by strong confinement in the direction perpendicular to the surface and much weaker confinement in the lateral direction. The spin relaxation is assumed to be due to…
The motion of molecules on solid surfaces is of interest for technological applications such as catalysis and lubrication, but it is also a theoretical challenge at a more fundamental level. The concept of activation barriers is very convenient for the interpretation of experiments and as input for Monte Carlo simulat…
Single crystals of the systems ${\mathrm{Pr}}_{0.5}({\mathrm{Ca}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{)}_{0.5}{\mathrm{MnO}}_{3},$ $({\mathrm{Pr}}_{1\ensuremath{-}y}{\mathrm{Y}}_{y}{)}_{0.5}({\mathrm{Ca}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{)}_{0.5}{\mathrm{MnO}}_{3},$ and ${\mathrm{Sm}}_{0.5}{\mathrm{Sr}}_{0.5}{\math…
X-ray absorption spectra in a wide energy range around the 4d-4f excitation threshold of Gd were recorded by total electron yield from in-plane magnetized Gd metal films. Matching the experimental spectra to tabulated absorption data reveals unprecedented short light absorption lengths down to 3 nm. The associated rea…
The addition of transition metal elements can significantly modify physical properties of intermetalic compounds. We studied the influence of Molybdenum and Vanadium additives on thermal expansion coefficient (CTE) of Fe/sub 3/Al and FeAl over the wide range of temperatures. The site preference of both transition meta…
The conductance of {\em cis/trans} isomers of stilbene molecules connected to armchair single wall carbon nanotubes is studied in the Landauer formalism combined with a density-functional based approach. For a given arrangement of the electrodes, dramatic differences in the transmission between both isomers are found.…
The ground state of an electrorheological (ER) fluid has been studied based on our recently proposed dipole-induced dipole (DID) model. We obtained an analytic expression of the interaction between chains of particles which are of the same or different dielectric constants. The effects of dielectric constants on the s…
Influence of number of particles considered in numerical simulations on complex dielectric permittivity of binary dilute dielectric mixtures in two-dimensions are reported. In the simulations, dodecagons (polygons with 12-sides) were used to mimic disk-shaped inclusions. Using such an approach we were able to consider…
BACKGROUND: Restenosis is a serious complication of coronary angioplasty that involves the proliferation and migration of vascular smooth muscle cells (VSMCs) from the media to the intima, synthesis of extracellular matrix, and remodeling. We have previously demonstrated that tissue factor-targeted nanoparticles can p…
A first-principles approach to the nonlinear flow of dense suspensions is presented which captures shear thinning of colloidal fluids and dynamical yielding of colloidal glasses. The advection of density fluctuations plays a central role, suppressing the caging of particles and speeding up structural relaxation. A mod…