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。
Fiber growth of Y 3 Al 5 O 12 (YAG) matrix composite reinforced with the sapphire phase was investigated to manufacture sapphire/YAG eutectic composites using the micro-pulling-down (µ-PD) method. Both the sapphire and YAG phases were crystalline. We have controlled the fiber diameter from 200 µm to 2 mm. The maximal…
The diffraction of stochastic point sets, both Bernoulli and Markov, and of random tilings with crystallographic symmetries is investigated in rigorous terms. In particular, we derive the diffraction spectrum of 1D random tilings, of stochastic product tilings built from cuboids, and of planar random tilings based on…
We have used X-ray photoelectron spectroscopy and Auger electron spectroscopy to examine the characteristics of oxide surfaces on a family of Al-Cu-Fe alloys. The alloys studied are compositionally similar but structurally different: two are crystalline and one is quasicrystalline. The samples all are formed by consol…
New crystalline materials of mixed composition based on the interaction between tetraarylporphyrin and 18-crown-6 derivatives have been prepared and characterized by X-ray diffraction analysis. Free crown ether macrocycles (18-crown-6 and dibenzo-18-crown-6) associate to manganese- or zinc-tetraphenylporphyrin in aque…
We performed the anionic living polymerization of 6-[4-(4‘-cyanophenyl)phenoxy]hexyl methacrylate. By a selection of suitable initiations, the cyano group was completely stable toward the propagating enolate anion, and the anionic polymerization proceeded with a living nature. The homopolymers could thus be prepared w…
Diagnostic analyses were performed on a d.c. carbon arc discharge using optical emission spectroscopy. The influence of the self-absorption on intensity distribution in the rotational structure of the C 2 (d g , v ´ = 0 a u , v ´´ = 0) emission band is discussed. The effect of the self-absorption was used in order to…
Interactions among local pit sites were investigated using an array of 25 electrodes. The 5 x 5 array consisted of closely spaced, flush-mounted 316 stainless steel wires polarized in 0.05 M NaCl solution. Two types of interactions occurred when either singl e or rows of actively corroding pits existed while the remai…
Aluminosilicate mesoporous molecular sieves exhibiting excellent structural ordering and enhanced acidity and catalytic activity have been prepared by reacting purely siliceous materials with Al-alkoxide in non-aqueous media. The Al is inserted into the framework of the purely siliceous parent material (MCM-41 or MMS)…
Improved synthetic methodology for poly(3-hexyl- and 3-octyloxycarbonylthiophene-2,5-diyl) (1a and 1b) is reported. n =6700 and 9400 ( w / n =2.5 and 3.2), λ max for fluorescence emission=600 and 610 nm and λ max for electroluminescence=600 and 615 nm, for 1a and 1b respectively. The 1 H NMR spectra required that pent…
Using W-band time-resolved EPR (TREPR) (95 GHz), the lowest excited doublet (D 1 ) state was observed in solution for the first time together with the excited quartet (Q 1 ) and doublet ground (D 0 ) states in a complex of MgTPP (TPP; tetraphenylporphyrin) and an axial-ligating p -pyridylnitronylnitroxide radical (nit…
The local electronic structure at the V2O5(010) surface is studied by abinitio density functional theory (DFT) methods where embedded clusters as large as V20O62H24, representing one or two physical layers of the substrate, are used as models. Results of local binding, charging, and densities of states help to charact…
In-situ transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) were used to study ion-beam-induced amorphization of Ca2La8(SiO4)6O2, a silicate ceramic with the apatite structure. In-situ TEM was performed during irradiation with 1 MeV Ar+, 1.5 MeV Kr+ and 1.5 MeV Xe+ ions…
To improve the surface blood compatibility on a cellulose hemodialysis membrane, 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers with a phospholipid polar group were immobilized on the surface through covalent bonding. The MPC polymers had a carboxylic group, which can react with hydroxyl groups on the cellulo…
Using molecular dynamics, it is shown that the equilibrium contact angle of a sessile drop placed on a heterogeneous substrate follows Cassie's law [Discuss. Faraday Soc. 57, 5041 (1952)]. The dynamics of the associated spreading is analyzed with the molecular kinetic theory. We show that the corresponding molecular p…
This paper discusses the optimization of the solvent evaporation process to produce double-walled (DW) microspheres in a single-step. Five process variables were studied: polymer solution concentration, polymer weight ratio, polymer solution volume ratios, encapsulation temperature, and air flow rate across the top of…
Hybrid materials made from polydimethylsiloxane and zirconium oxo species have been synthesized. They exhibit a high degree of homogeneity and dispersion for Zr/Si molar ratios ranging between 0.2 and 0.9. These hybrid materials show good mechanical integrity and transparency. They have been characterized by 29 Si, 17…
T. L. Morkved, B. R. Chapman, F. S. Bates, T. P. Lodge, P. Stepanek and K. Almdal, Faraday Discuss., 1999, 112, 335 DOI: 10.1039/A809169B
The synthesis of novel dendrimers with various functional cores, including those of the porphyrin macrocycle, has been a very active area of research. Phthalcyanine (Pc), a close relative of porphyrin, and its derivatives form one of the most studied classes of functional organic materials. The author briefly summariz…
films have been grown by laser ablation on (100) oriented Si and GaAs substrates. Optimal growth of was obtained at a substrate temperature of 450 C in a molecular oxygen atmosphere of Torr. X-ray measurements show these films to be (111) oriented, with the growth direction random in the plane of the film. The introdu…
Two strategies have been employed in the construction of multiporphyrin arrays; the principles are illustrated by a seven-porphyrin array consisting of two three-porphyrin dendrons coordinated to a single ruthenium(II) porphyrin, and by a six-porphyrin array containing three ruthenium(II) porphyrinmonomers coordinated…