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。
An outstanding example of structural diversity and complexity is found in the compounds with the general formula ABi(3)Q(5) (A = alkali metal; Q = chalcogen). gamma-RbBi(3)S(5) (I), alpha-RbBi(3)Se(5) (II), beta-RbBi(3)Se(5) (III), gamma-RbBi(3)Se(5) (IV), CsBi(3)Se(5) (V), RbBi(3)Se(4)Te (VI), and RbBi(3)Se(3)Te(2) (…
Electron paramagnetic resonance (EPR) measurements on pure polycrystalline CaCu 3 Ti 4 O 12 have been performed and are discussed within a crystal-field approach. A symmetric signal centred at g = 2.15 is observed for T >25 K, with no evidence of hyperfine structure. At this temperature an antiferromagnetic transition…
We report the synthesis of monomers, dimers, trimers, and oligomers of triple-decker (TD) complexes bearing S-acetylthio groups at the termini: AcS-(TD)(n)()-SAc. Each TD was of type (Pc)Eu(Pc)Eu(Por), where H(2)Pc = tetra-tert-butylphthalocyanine and H(2)Por is a meso-tetraarylporphyrin bearing functional groups at t…
Adequately substituted porphyrins can participate in pericyclic reactions as dienes, dienophiles, dipolarophiles and as 1,3-dipoles. They also show interesting dipolar 1,5-electrocyclizations and cheletropic reactions with carbenes. All these different types of reactivity have been exploited in order to synthesize new…
The segregation of native defects and Bi impurities to a high-angle grain boundary in ZnO is studied by first-principles calculations. It is found that the presence of Bi(Zn) increases the concentration of native defects of acceptor type in the grain boundary. This leads to the formation of a Bi(Zn)+V(Zn)+O(i) interfa…
Recently developed versatile biodegradable polymeric biomaterial offer new therapeutic options in numerous medical fields. Biocompatibility is a crucial requirement for the biomedical application of biomaterials, including the sterilization of these materials with the use of accepted protocols. Ethylene-oxide (EO) and…
Nonquasiparticle states above the Fermi energy are studied by first-principle dynamical mean field calculations for a prototype half-metallic ferromagnet NiMnSb. We present a quantitative evaluation of the spectral weight of this characteristic feature and discuss the possible experimental investigation (Bremsstrahlun…
Titanium and its alloys are the most suitable materials for structural biomaterials among metallic biomaterials. Nowadays, Pure Ti and Ti-6Al-4V ELI are the most widely used in the biomedical fields. However, for replacing failed hard tissue, the strength of pure Ti is not sufficient. For Ti-6Al-4V ELI, V has been poi…
Broadband dielectric spectroscopy is employed to investigate the molecular dynamics of cis-1,4-polyisoprene (PI) in thin layers down to thicknesses comparable with the chain extension. The segmental and the normal mode dynamics of the PI chains is found not to depend on the layer thickness. Additionally, a novel confi…
The crystal structure of the Escherichia coli lactose permease at 3.5 A with a bound substrate has been reported recently. The structure reveals the sugar-protein contacts, which include hydrophobic stacking between the galactopyranosyl ring of substrate and the indole side chain of Trp-151, as proposed previously. Th…
Metallic nanowires composed of nickel and gold as well as bimetallic nickel−gold nanowires were fabricated via templated electrodeposition in nanoporous alumina membranes. Gold surfaces were functionalized with alkanethiols with terminal hexa(ethylene glycol) groups (EG 6 ), while nickel surfaces were functionalized w…
Several types of six-armed, metal tris(bipyridine) core dendrimers were synthesized. Bis-4,4'-alkoxy bipyridine dendrons were prepared and employed to make tris(bipyridine) dendrimers. Although the ruthenium-centered and iron-centered dendrimers displayed quasi-reversible cyclic voltammetry, the analogous cobalt-cente…
Using X-ray scattering complemented by microscopic methods, we studied the alignment of a semicrystalline polymer isotactic polystyrene by crystallization in a high magnetic field (7 and 11 T). As reported previously, strong orientation of crystalline chain segments perpendicular to the magnetic field can be achieved.…
Structure and magnetic transitions were investigated by x-ray diffraction and Mössbauer spectroscopy in LaFe 13− x Si x compounds with x = 1.6, 2.0 and 2.6. With increasing Si content, the La–Fe interatomic distance decreased while the average Fe–Fe distance increased. These changes affect the structural stability and…
Abstract Hetero‐bimetallic Fe(II) alkoxide/aryloxides were evaluated as initiators for the ring‐opening polymerization of rac ‐lactide. [(THF)NaFe(O t Bu) 3 ] 2 ( 1 ) and [(THF) 4 Na 2 Fe(2,6‐diisopropylphenolate) 4 ] ( 2 ) (THF = tetrahydrofuran) both polymerized lactide efficiently at room temperature, with complex…
A series of cyano-bridged heterotrimetallic complexes [CuL](2)Ln(H(2)O)(2)M(CN)(6).7H(2)O have been synthesized by the reactions of CuL (L(2)(-) = dianion of 1,4,8,11-tetraazacyclotradecane-2,3-dione), Ln(3+) (Ln = Gd or La), and [M(CN)(6)](3)(-) (M = Co, Fe, or Cr). X-ray diffraction analysis reveals that these compl…
Three new compounds [Ln(NMP)(4)(H(2)O)(4)][H(x)()GeMo(12)O(40)].2NMP.3H(2)O (Ln = Ce(IV) (1), Pr(IV) (2), x = 0; Ln = Nd(III) (3), x = 1; NMP = N-methyl-2-pyrrolidone) have been prepared in aqueous solution and characterized by elemental analyses, IR, UV-vis, and TG analyses. The single crystal X-ray diffraction shows…
We have grown epitaxial CeO 2 buffer layers on biaxially textured Ni–W substrates for YBCO coated conductors using a newly developed metal organic decomposition (MOD) approach. Precursor solution of 0.25 M concentration was spin coated on short samples of Ni–3 at%W (Ni–W) substrates and heat-treated at 1100 °C in a ga…
Three-dimensional degradable porous polymeric structures with high porosities (93-98%) and well-interconnected pore networks have been prepared by freeze-drying polymer solutions in the presence of a leachable template followed by leaching of the template. Templates of the pore network were prepared by fusing sugar or…
Notch receptors and the amyloid precursor protein are type I membrane proteins that are proteolytically cleaved within their transmembrane domains by a presenilin (PS)-dependent gamma-secretase activity. In both proteins, two peptide bonds are hydrolyzed: one near the inner leaflet and the other in the middle of the t…