Materials Literature
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Polarization state in epitaxial thin films of relaxor ferroelectric PbMg1∕3Nb2∕3O3 (PMN) was experimentally studied at the nanoscale using a piezoresponse force microscopy (PFM). In the absence of a dc bias applied to the PFM tip, no piezoelectric activity could be found on most of the surface of the film. Under a mod…
A minimal coupling model exhibiting isotropic, uniaxial, and biaxial nematic phases is analyzed in detail and its relation to existing models known in the literature is clarified. Its intrinsic symmetry properties are exploited to restrict the relevant ranges of coupling constants. Further on, properties of the model…
The preparation of platinum (0−2 wt %) supported on ceria/zirconia (Ce 0.5 Zr 0.5 O 2 ) by flame synthesis resulted in materials with good thermal stability and improved dynamic oxygen exchange capacity at low temperatures. Comparison to a conventionally prepared material (precipitation and incipient wetness impregnat…
The most stable structure of aluminum hydride $\mathrm{Al}{\mathrm{H}}_{3}$ is believed to be a hexagonal symmetry. However, using the density functional theory, we have identified two more stable structures for the $\mathrm{Al}{\mathrm{H}}_{3}$ with the cubic and orthorhombic symmetries. Based on the quasiharmonic ap…
Novel biocompatible and biodegradable amphoteric poly(amidoamine) (PAA) hydrogels were designed for applications as scaffolds for tissue engineering. These hydrogels (PAA-AG1 and PAA-AG2) were obtained by polyaddition of 2,2-bisacrylamidoacetic acid with 2-methylpiperazine and 4-aminobutyl guanidine, a bioactive molec…
CoO x /CeO 2 nanocomposite materials with increasing Co/Ce atomic ratio were prepared by wet impregnation and characterized by means of X-ray photoelectron, diffuse reflectance infrared Fourier transform, and inductively coupled plasma atomic emission spectroscopic techniques, by BET and by thermal analysis. CoO is pr…
This study presents syntheses, structural characterization, and crystallization kinetic investigation of new structurally well-defined star-shaped poly(l-lactide)s (PLLAs). First, a series of new 3- to 6-arm star-shaped PLLAs were synthesized through SnOct(2) catalyzed ring-opening polymerization of (l)-lactide with n…
Organic dye nanoparticles 1-13 nm in height and 10-45 nm in width were prepared by the reprecipitation method. With single-molecule/nanoparticle spectroscopy, two distinct types of nanoparticles were found: particles with blue emission and particles with red emission. The difference in spectral characteristics is attr…
We report the discovery, synthesis, and crystallographic binding mode of novel furanopyrimidine and pyrrolopyrimidine inhibitors of the Chk1 kinase, an oncology target. These inhibitors are synthetically tractable and inhibit Chk1 by competing for its ATP site. A chronological account allows an objective comparison of…
The static and dynamic mechanical properties of banana and glass woven fabric-reinforced polyester composites have been determined with special reference to the effect of fiber volume fraction, layering pattern, and the weaving architecture. Even though articles related to natural fiber composites are abundant in the…
Reverse w/o microemulsions composed of methyl methacrylate (MMA) forming the oil phase, nonionic surfactants, and water are used for the synthesis of transparent SiO2/PMMA nanocomposites. An inorganic precursor, tetraethoxysilane (Si(OEt)(4), TEOS), is hydrolyzed in the reverse micelles containing aqueous ammonia. Dur…
A novel self-assembled microstructure, nestlike Mg(5)(CO(3))(4)(OH)(2).4H(2)O spheres, is formed by a self-assembly of nanosheets in the hydrothermal process. MgO with the similar morphology can be obtained by calcination of nestlike Mg(5)(CO(3))(4)(OH)(2).4H(2)O. MgO precursors with a uniform, ellipsoid-shaped, and s…
Large-scale alignment of bilayer block copolymer films by applying in-plane shear is demonstrated. The method eliminates all disclinations and most dislocations from arbitrarily large samples, as evidenced by atomic force microscopy of the microdomain lattice (Figure, left) as well as its Fourier transform (Figure, ri…
Sphere we go: A spherical capsule is prepared simply by the interaction of linkers to pentagonal structural units. The metal centers (M) of the {(MoVI)MoVI5}12M30 type Keplerates formed (M=VIV, FeIII) describe an icosidodecahedron (see picture). For M=FeIII the magnetic configuration of the 30 spin centers (colored sp…
In this paper, explicit method of constructing approximations (the Triangle Entropy Method) is developed for nonequilibrium problems. This method enables one to treat any complicated nonlinear functionals that fit best the physics of a problem (such as, for example, rates of processes) as new independent variables. Th…
Symmetric and nonsymmetric diarylethenes with a 2,5-dihydropyrrole bridging unit have been prepared, and the photochromic properties are investigated. Both symmetric and nonsymmetric diarylethenes with 2,5-dihydropyrrole bridging units undergo reversible ring-opening and ring-closing photoisomerization reactions in no…
Heat capacity measurements of the delta-phase stabilized alloy Pu-Al suggest that strong electron-phonon coupling is required to explain the moderate renormalization of the electronic density of states near the Fermi energy. We calculate the heat capacity contributions from the lattice and electronic degrees of freedo…
The theoretical and experimental investigation of ferroelectric nanopowders is performed. The manifestation in radiospectroscopy spectra of size driven ferroelectric-paraelectric phase transition at some critical particle average size was the main goal of the consideration. In theoretical part the size effect for the…
The heats of formation for the borane amines BH3NH3, BH2NH2, and HBNH, tetrahedral BH4-, and the BN molecule have been calculated by using ab initio molecular orbital theory. Coupled cluster calculations with single and double excitations and perturbative triples (CCSD(T)) were employed for the total valence electroni…
All aglow: A new class of highly luminescent dyes is built by the attachment of a pyrene fragment to the boron center of a boradiazaindacene moiety through an ethynyl unit (see scheme). Very efficient energy transfer from the pyrene to the indacene center produces virtual large Stokes shifts, which are maintained, alo…