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。
There have been many investigations on the effect of solvents on the dynamic moduli of concentrated polymer solutions. However, most of the polymers investigated were nonpolar, such as polystyrenes and polybutadienes. Moreover, the samples were usually model polymers of very narrow molecular weight distribution and we…
The preparation of solid solutions of the sulfides of zinc, cadmium, and lead has been attempted by low-temperature pyrolysis (150−400 °C) of metal bis(benzylthiolate) precursors. The (Zn,Cd)S shows solid solution behavior at 200−400 °C and crystallite sizes of ∼5 nm. The CdS−PbS system was also prepared by the precur…
The relative merits of the moving packed bed, fluidized bed, and stirred bed reactors for solid-state polycondensation are discussed along with methods for improving these designs. A general model to describe continuous solid-state polymerization reactors is then developed and illustrated by a case study of a moving p…
Weblike aggregates of Si nanocrystals and tungsten oxide nanoparticles are produced by a laser vaporization controlled condensation technique. XRD, FTIR, and Raman results confirm that the Si nanoparticles have a diamond-like crystalline structure and WO 3 nanoparticles exhibit a monoclinic crystalline structure. Due…
Single crystals of the trivalent Al 3+ ion conductor Al 2 (WO 4 ) 3 were grown by the Czochralski (CZ) method. The ionic conductivity in the a -, b -, and c -axis directions was determined and Al 3+ ion conduction in the direction of the b -axis was concluded to be the most suitable pathway for ion migration in the tu…
2,3-Bis(4-aminophenyl)quinoxaline (1a), 2,3-bis(4-aminophenyl)-6-methylquinoxaline (1b), and 5,6-bis(4-aminophenyl)-3-(2-pyridyl)-1,2,4-triazine (2) were studied as curing agents of epoxy resins. The exotherms on differential scanning calorimetry thermograms of the mixtures of diglycidyl ether of bisphenol A (DGEBA) w…
The reaction of Cu with a molten mixture of A 2 S/P 2 S 5 (A = K, Rb, Cs) produced the quaternary compounds A 2 CuP 3 S 9 (A = K, Rb) and Cs 2 Cu 2 P 2 S 6 . The reaction of Cu with a molten mixture of K 2 S/P 2 S 5 /S produced the quaternary compound K 3 CuP 2 S 7 . A 2 CuP 3 S 9 (A = K, Rb); I, II, respectively) cry…
The electrochemical atomic layer epitaxy methodology was employed to obtain CdS deposits on Ag(111) by alternate underpotential deposition of up to five layers of sulfur and four layers of cadmium. The charge involved in each layer was determined by cyclic voltammetry. With the exception of the first sulfur layer, the…
Organized bacterial superstructures have been used as 3-D templates for the fabrication of ordered inorganic−organic fibrous composites. Preformed magnetic (Fe 3 O 4 ) and semiconducting (CdS) inorganic nanoparticles were incorporated into macroscopic threads of Bacillus subtilis by reversible swelling of the superstr…
An attempt was made to encapsulate iron nanoparticles in uniform carbon nanotubes, which were prepared by using an anodic aluminum oxide film as a template. The pyrolytic carbon deposition from propylene was carried out on the uniform channels of the anodic oxide film, and then the MOCVD (metal−organic chemical vapor…
Microporous polysulfone hollow fibers were developed with the help of chemical blowing agents by means of extrusion. Two chemical blowing agents, azodicarbonamide and 5-phenyltetrazol, were selected, and the foam morphology dependent on the concentration of blowing agent was examined by scanning electron micrograph. B…
Hydrothermal synthetic investigations to prepare new A(2)Mo(3)TeO(12) (A = NH(4), Cs, Rb, K) compounds are described. Novel noncentrosymmetric layered tellurites, (NH(4))(2)Mo(3)TeO(12) (1) and Cs(2)Mo(3)TeO(12) (2), have been synthesized by hydrothermal methods. Their structures contain two-dimensional hexagonal tung…
Langmuir−Blodgett films consisting of carbon single-walled nanotubes embedded in a surfactant matrix were prepared. Aqueous dispersions of single-walled nanotubes stabilized by lithium dodecyl sulfate were purified by a centrifugation step. The supernatant was spread onto a subphase containing a positively charged pol…
[Fe(hyetrz) 3 ](3-nitrophenylsulfonate) 2 ·3H 2 O ( 1 · 3H 2 O), with hyetrz = 4-(2‘-hydroxyethyl)-1,2,4-triazole, has been synthesized, and its physical properties have been investigated with several techniques, including optical and Mössbauer spectroscopies, magnetism at different pressures up to ca. 9 kbar, thermog…
The Keggin-type iron-substituted polyoxometalates have been used as catalysts for the oxygenation of alkanes in homogeneous reaction media using hydrogen peroxide as an oxygen donor. The efficiency and activity for the utilization of hydrogen peroxide greatly depended on the iron centers and diiron-substituted [γ-SiW…
We use the grand canonical Monte Carlo method to study the nature of wetting transitions on a variety of heterogeneous surfaces. The model system we explore, Ne adsorption on Mg, is one for which a prewetting transition has been found in our previous simulations. We find that the first order transition present on the…
The folding pattern of the segment of alphaA-crystallin encoded by exon 2 and containing putative substrate binding sites was explored using site-directed spin labeling (SDSL). For this purpose, a nitroxide scan was carried out between residues 60 and 108. At each site, structural constraints describing the local envi…
Traditionally, the physics of magnetism has been divided into two almost independent branches. The first branch deals with interactions at the atomic level. When applied to the three-dimensional world, it mostly consists of challenging unsolved problems like the Ising, Habbard, and Heisenberg Hamiltonians, Fermi-liqui…
The occurrence of the glyoxylate cycle has not previously been demonstrated in any of the Archaea. In halophilic archaea, only isocitrate lyase activity has been detected. The halophilic archaeon Haloferax volcanii was tested for the presence of the other key enzyme of this pathway, malate synthase. High activities of…
Ab initio calculations were performed, using the CASPT2 method and moderate-size basis sets, on several d 6 octahedral coordination compounds, Fe(CN) 6 4-, Fe(NCH) 6 2+, cis - and trans -Fe(CN) 2 (NCH) 4, and Cr(CO) 6 . The study concentrates on the six lowest states of the d → d spectrum (three singlets, one quintet,…