Materials Literature
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We validate that off-resonant electron transport across {\it ultra-short} oligomer molecular junctions is characterised by a conductance which decays exponentially with length, and we discuss a method to determine the damping factor via the energy spectrum of a periodic structure as a function of complex wavevector. A…
A monoethylaluminum Schiff base complex (2) with formula LAlEt (L = N,N'-(2,2-dimethylpropylene)bis(3,5-di-tert-butylsalicylideneimine) was synthesized and employed for the stereoselective ring-opening polymerization of rac-lactide (rac-LA). The complex 2 was characterized by nuclear magnetic resonance, crystal struct…
Marine benthic diatoms excrete large quantities of extracellular polymeric substances (EPS), both as a function of their motility system and as a response to environmental conditions. Diatom EPS consists predominantly of carbohydrate‐rich polymers and is important in the ecology of cells living on marine sediments. Pr…
Raman spectra of ZnO powder and free-standing nanowires prepared by laser ablation have been studied. All observed vibrational modes in ZnO powder, both first order and higher order scattering, were assigned on the basis of group theoretical analysis. The size dependence of the coupling strength between electron and l…
Single walled carbon nanotubes with Pd Ohmic contacts and lengths ranging from several microns down to 10 nm are investigated by electron transport experiments and theory. The mean-free path (MFP) for acoustic phonon scattering is estimated to be l(ap) approximately 300 nm, and that for optical phonon scattering is l(…
Carbon nanotubes are exceptionally interesting from a fundamental research point of view. Many concepts of one-dimensional physics have been verified experimentally such as electron and phonon confinement or the one-dimensional singularities in the density of states; other 1D signatures are still under debate, such as…
Incommensurately modulated ammonium tetrafluoroberyllate (AFB) occurs in a narrow temperature interval between the paraelectric room-temperature phase with space group Pnma (Ti = 178 K) and the ferroelectric low-temperature phase with space group Pna2(1) (Tc = 173 K). The structure is determined from accurate single-c…
The homodimeric HU protein from the hyperthermophile Thermotoga maritima (HUTmar) is a model system which can yield insights into the molecular determinants of thermostability in proteins. Unusually for a thermostable protein, HUTmar exists in a structurally heterogeneous state as evidenced by the assignment of two di…
Abstract The title compound (C 14 H 10 N 2 O 2 Cl 2 ) crystallizes in the monoclinic space group P2 1 /a with a=10.042(1) Å, b=10.317(1) Å, c=13.877(2) Å, β=97.36(2)°, V=1425.8(3) Å 3 , Z=4, D x =1.44 g.cm ‐3 . The structure was solved by direct methods and refined by full‐matrix least‐squares method (R = 0.0457). The…
The fcc Zr2Ni- and MgCu2-type phases, being primary crystalline products of certain amorphous alloys with high glass-forming ability, should provide local structural information about the related amorphous alloys. The present paper gives a detailed analysis of the common structural features of these two fcc phases. Th…
Abstract Interactions between poly(maleic anhydride‐ alt ‐acrylic acid), [poly(MA‐ alt ‐AA)] and Cu 2+ , Ni 2+ , and Cd 2+ ions were studied by UV–vis spectroscopy and viscosimetry. Effects of nature and the concentrations of the metal ions on the complex formation were investigated and the formation constants of each…
A new method for the synthesis of monolayer-protected silver clusters (MPCs) based on the two-phase reduction of a stable negatively charged silver bromide sol is described. Phase transfer of the colloid to toluene is accomplished using tetra-n-octylammonium bromide as the phase transfer reagent. The advantage of this…
Abstract The compatibilizing effect of the ionomer, poly(styrene‐ co ‐sodium acrylate) (PSSAc), on immiscible blends of polystyrene (PS)/polyamide 6 (PA6) was studied by mechanical tests and scanning electron microscopy. The PSSAc acts as an effective compatibilizer because both the deformation at break (%) obtained b…
The optical and magneto-optical (MO) spectra of the lanthanum monochalcogenides are investigated theoretically using the fully relativistic Dirac LMTO band-structure method. The LSDA calculations with shifted La $4f$ empty states describe quite well the shape and magnitude of the LaS MO spectra in an external magnetic…
This study investigated the relaxation behaviors of octadecylamine (ODA), stearic acid (SA), and SA/ODA mixed monolayers at the air/water interface. Area relaxations of monolayers at constant surface pressure were studied by a nucleation and growth mechanism and by direct observation using a Brewster angle microscope…
Abstract Two different hydrogels, prepared from N ‐vinyl‐2‐pyrrolidone/acrylic acid (NVP/AAc) and N ‐vinyl‐2‐pyrrolidone/acrylamide (NVP/AAm), were studied for the separation and extraction of some heavy‐metal ions from wastewater. The hydrogels were prepared by the γ‐radiation‐induced copolymerization of the aforemen…
Abstract Composites of palm fibers and poly(propylene) (PP) were compounded in an extruder at 200°C. The composites were subsequently injection molded into standard tensile specimens for mechanical characterization. The fracture morphology of the specimens was analyzed by scanning electron microscopy. It was observed…
Abstract Single crystals of Pb 3 O 2 (SeO 3 ) have been prepared hydrothermally at 230 °C. The structure (orthorhombic, Cmc 2 1 , a = 10.529(2), b = 10.722(2), c = 5.7527(12)Å, V = 649.5(2)Å 3 ) has been solved by direct methods and refined to R 1 = 0.059 on the basis of 615 unique observed reflections (| F o | = 4σ F…
Efficient quantitative phase field simulation using an adaptive finite volume method with an antisolutal trapping scheme is presented for a binary dendritic growth in a forced flow. For the case of no convection, the calculated results with different interface thickness are examined. It is found that with a proper ant…
Highly reflective and surface conductive flexible polyimide films have been prepared by the incorporation of silver(I) acetate and 1,1,1-trifluoro-2,4-pentanedione or 1,1,1,5,5,5-hexafluoro-2,4-pentanedione into a dimethylacetamide solution of the poly(amic acid) formed from 3,3‘,4,4‘-biphenyltetracarboxylic dianhydri…