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。
The formation of a Ag stabilized regular step lattice on vicinal Si(111) miscut towards [11-2] is reported. The step bunching characteristic of the clean surface is prevented by a single-domain Si(111)-(3x1)-Ag reconstruction. The nanostructured surface is used as a template for growing one-dimensional arrays of 1 nm…
The spin glasses are disordered and frustrated magnetic systems. They show aging phenomena which are also a characteristic feature of structural glasses, polymers, dielectrics, colloids, etc. Under a strong enough magnetic field variation, spin glasses can be "rejuvenated", in the same way as glasses under a high enou…
It has been observed that the van der Waals interaction can cause an extruded core of a multiwalled carbon nanotube (MWNT) to retract into the outer shells. In a previous report [Q. Zheng and Q. Jiang, Phys. Rev. Lett. $88,$ 045503 (2002)], the authors pointed out that the restoring force resulted from the excess van…
Abstract Polypropylene (PP) nanocomposites were prepared by melt intercalation in an intermeshing corotating twin‐screw extruder. The effect of molecular weight of PP‐MA (maleic anhydride‐ modified polypropylene) on clay dispersion and mechanical properties of nanocomposites was investigated. After injection molding,…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of the Lanthanides Using Pyrazolylborate LigandsNoémia Marques, Andrea Sella, and Josef TakatsView Author Information Departamento de Química, ITN, Estrada Nacional 10, P-2686-953, Sacavém Codex, Portugal; Christopher Ingold Laboratories, Department of Chemistry, U…
Spurred by the recent demonstrations of the size- and support-dependent reactivity of supported gold clusters, here we present results on the coadsorption of CO and O(2) on selected anionic gold clusters, Au(N)(-), in the gas phase. O(2) adsorbs in a binary (0,1) fashion as a one-electron acceptor on the Au(N)()(-) cl…
The disordered nature of glass-forming melts gives rise to non-Arrhenius and non-exponential behaviour of their dynamics. With respect to the microscopic details involved in the structural relaxation, these materials have remained an unsolved puzzle for over a century. The observation of spatial heterogeneity regardin…
The materials community in both science and industry use crystallographic data models on a daily basis to visualize, explain and predict the behavior of chemicals and materials. Access to reliable information on the structure of crystalline materials helps researchers concentrate experimental work in directions that o…
A transmission electron microscopy (TEM) study was made to investigate the mechanism of isothermal crystallization from melt for syndiotactic polypropylene (sPP) with a syndiotactic pentad fraction of 0.92. The TEM morphologies of RuO4-stained and ultrathin-sectioned specimens revealed a clear assignment of lamellar c…
Abstract Historically, polyaniline (PANI) had been considered an intractable material, but it can be dissolved in some solvents. Therefore, it could be processed into films or fibers. A process of preparing a blend of conductive fibers of PANI/poly‐ω‐aminoundecanoyle (PA11) is described in this paper. PANI in the emer…
We developed a specimen-drift-free energy-dispersive X-ray (EDX) mapping system in a scanning transmission electron microscope (STEM) to improve the sensitivity and spatial resolution of EDX elemental mapping images. The amount of specimen drift was analysed from two STEM images before and after specimen drift by usin…
A new method of protein crystallization based on a homologous Langmuir-Schaefer (LS) protein thin-film template proves to successfully stimulate crystal nucleation and growth of the four different proteins being studied, under different crystallization conditions including those failing to lead to crystal formation in…
Piezoforce microscopy (PFM) has been used to determine the domain structure of lead zirconate titanate (PZT) (30/70) on an indium tin oxide (ITO)/glass substrate with a TiO 2 boundary layer. The PZT nucleates into the perovskite form in a random crystallographic manner, which leads to a random domain structure in the…
We present a detailed de Haas-van Alphen effect study of the perovskite CaVO3, offering an unprecedented test of electronic structure calculations in a 3d transition metal oxide. Our experimental and calculated Fermi surfaces are in good agreement, but only if we ignore large orthorhombic distortions of the cubic pero…
Abstract Carboxymethyl chitosan sodium (CMCTS) was synthesized by chitosan and chloroacetic acid under an alkali catalyst. Acrylic acid sodium salt and methylacrylic acid sodium salt were grafted onto CMCTS to obtain copolymers with good water solubility. The graft reaction was carried out at 70°C for 2 h, and ammoniu…
Tungstate exchanged Mg-Al layered double hydroxides a as recyclable heterogenised catalyst along with H2O2 as an oxidant for the oxidation of sec-amines to nitrones is developed for the first time, Reactions proceed at a fast rate in aqueous media in a single step at room temperature in good to excellent yields. The h…
The electronic transitions from deep core levels, semicore levels, and valence bands to the empty conduction bands in yttrium aluminum garnet $({\mathrm{Y}}_{3}{\mathrm{Al}}_{5}{\mathrm{O}}_{12})$ (YAG) are studied by first-principles calculations that explicitly take into account the excitonic effect. The electron en…
Abstract Linear low‐density polyethylenes and low‐density polyethylenes of various compositions were melt‐blended with a batch mixer. The blends were characterized by their melt strengths and other rheological properties. A simple method for measuring melt strength is presented. The melt strength of a blend may vary a…
The effects of accelerating voltage and collection angle on the mean free path for all inelastic electron scattering (lambdap), which is an important parameter for determining specimen thickness by using electron energy-loss spectroscopy, were investigated with crystalline Si and amorphous SiO2. First, thickness of Si…
Abstract The polymerizable cationic surfactant, vinylbenzyldimethylethanolammouium chloride (VBDEAC), was synthesized to functionalize montmorillonite (MMT) clay and used to prepare exfoliated polystyrene–clay nanocomposites. The organophilic MMT was prepared by Na + exchanged montmorillonite and ammonium cations of t…