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。
Due to their technological importance, point defects in silicon are among the best studied physical systems. The experimental examination of point defects buried in bulk is difficult and evidence for the various defects usually indirect. Simulations of defects in silicon have been performed at various levels of sophis…
We consider a mean-field approach to the hole-mediated ferromagnetism in III-V Mn-based semiconductor compounds to discuss the dependence of the hole density on that of Mn sites in Ga_{1-x}Mn_xAs. The hole concentration, p, as a function of the fraction of Mn sites, x, is parametrized in terms of the product m*J_{pd}^…
We present a microscopic model for systems showing resistivity saturation. An essentially exact quantum Monte-Carlo calculation demonstrates that the model describes saturation. We give a simple explanation for saturation, using charge conservation and considering the limit where thermally excited phonons have destroy…
We calculate the energy dispersion of the surface Andreev states and their contribution to tunneling conductance for the order parameters with horizontal and vertical lines of nodes proposed for superconducting Sr2RuO4. For vertical lines, we find double peaks in tunneling spectra reflecting the van Hove singularities…
A series of tensile relaxation tests is performed on isotactic polypropylene in the sub-yield and post-yield regions at room temperature. Constitutive equations are derived for the time-dependent response of a semicrystalline polymer at isothermal loading with small strains. Adjustable parameters in the stress-strain…
We refute recent claims that ultrafast atomic jumps as observed in quasicrystals (QC) could be called phasons in many crystalline alloys by pointing out that there is a genuine conceptual difference between the hopping dynamics in an imperfect crystal containing a substantial number of vacancies, and the hopping dynam…
The influence of an external field on a binary colloidal mixture performing Brownian dynamics in a solvent is investigated by nonequilibrium computer simulations and simple theory. In our model, one half of the particles are pushed into the field direction while the other half of them are pulled into the opposite dire…
High quality thin films of the ferromagnetic semiconductor EuO have been prepared and were studied using a new form of spin-resolved spectroscopy. We observed large changes in the electronic structure across the Curie and metal-insulator transition temperature. We found that these are caused by the exchange splitting…
To evaluate the influence of substratum surface characteristics on protein adsorption processes, we have investigated the adsorption (adsorbed amount, supramolecular organization) of collagen on model substrata exhibiting controlled topography and surface chemistry. Substrata were prepared in two steps: (i) gold depos…
Mesostructured TiO 2 −hexadecyltrimethylammonium bromide hybrid powders, displaying a bidimensional hexagonal pattern (p6m), have been synthesized by an evaporation-induced self-assembly (EISA) method, in ethanol/HCl/H 2 O media. Thermal treatment of these “titaniatropic” hybrid phases leads to phosphorus-free, high s…
The methods of preparation and formation of supermolecular structures in quiescent and sheared melts and the properties of the β-modification of isotactic polypropylene (β-iPP) are reviewed. The introduction of selective β-nucleants is the most reliable method for preparation of samples rich in β-modification or of pu…
We report results of measurements of the optical constants of the dielectric layer (ZnS-SiO2), reflecting layer (aluminum-chromium alloy), and phase-change layer (GeSbTe, AgInSbTe) used as the media of phase-change optical recording. The refractive index n and the absorption coefficient k of these materials vary to so…
Abstract A method for the calculation of connectivity indices of polymers was developed that can be used to calculate any order connectivity indices of polymers in a consistent and unambiguous manner without any truncation errors. The proposed method makes it possible to correlate the physical properties of polymers i…
A hydrophilic phosphine oxide (1) as a suitable ligand for semiconductor nanoparticles was synthesized. The hydrophilicity of the phosphine oxide was enhanced by introduction of three mannose moieties to the end of the molecule via amide linkages. The ligand 1 was able to coordinate to the CdSe/ZnS nanoparticle making…
Electron spin resonance spectroscopy has been used to detect the photoionization yield of meso -tetraphenylporphyrin (H 2 TPP) in SiMCM-48, AlMCM-48, and TiMCM-48 mesoporous molecular sieves. MCM-48 materials are shown to be effective heterogeneous hosts to accomplish long-lived photoinduced electron transfer of bulky…
The aim of this paper was to improve the knowledge of the primary producers living in the Venice Lagoon by studying the composition and the distribution of the benthic diatom communities populating subtidal surface sediments. The upper 5mm of sediment from four areas distributed between the Malamocco inlet and the mai…
Abstract We report molecular dynamics simulations which investigate the influence of two parallel free surfaces in the deformation mechanisms of model nanocrystalline fee materials. The purpose of this simulation is to study which phenomena observed in in-situ tensile experiments performed in the electron microscope c…
The synthesis and electrochemical properties of a new organic donor, (1,4-dioxan-2,3-diyldithio)dihydrotetrathiafulvalene (DODHT), and the crystal structures and physical properties of its superconducting salts are described. The DODHT molecule has the bulky dioxane ring condensed by cis fusion, and the reduced pi-ele…
Triruthenium dodecacarbonyl (Ru 3 (CO) 12 ) adsorption and decomposition on titania (TiO 2 ) were studied using infrared reflection absorption spectroscopy, temperature-programmed desorption, Auger electron spectroscopy, and scanning tunneling microscopy. It was found that the vapor-deposited cluster adsorbs with the…
The presence of calcium lactate (CaL2) crystals on the surface of Cheddar cheese is an appearance defect that consumer often attributes to mold. This problem is widespread in the cheese industry. The solubility of CaL2in water determines the likelihood of formation of CaL2crystals on the surface of Cheddar cheese. Ver…