Materials Literature
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Cs+, and Ni2+, Mn2+ or Fe3+ substitution for H+ in H3PMo12O40 greatly enhanced the catalytic activity for the title reaction and among the catalysts tested Cs2.5Ni0.08H0.34PMo12O40 gave the highest yield of methacrylic acid and methacrolein.
Abstract
In this paper we report the construction of both slot capacitors on bulk substrate and thin film interdigital capacitors using YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) and Ba/sub x/Sr/sub 1-x/TiO/sub 3/. Slot capacitors made on bulk Ba/sub x/Sr/sub 1-x/TiO/sub 3/ (BST) yielded variations in capacitance of more t…
The ability of the scalar Preisach model (PM) to describe magnetic interactions and Henkel plots is discussed. It is shown that the random interactions described by the PM switching field distribution p(/spl alpha/,/spl beta/) always have a net demagnetizing-like effect on remanences. The connection between the proper…
Electron crystallography constitutes a powerful new method for determining the structure of biological macromolecules. This method is best adapted to the study of ordered assemblies of macromolecules, and principally to two-dimensional (2-D) crystals of proteins. Obtaining protein 2-D crystals ordered at high resoluti…
We have studied the magnetic properties of fine particles of iron and iron carbide nested in carbon cages (nanocapsules), which were synthesized by arc discharge of carbon rods. It is clarified by Mössbauer spectroscopy and thermomagnetic ( M-T ) curve that these particles consist of α-Fe, γ-Fe and Fe 3 C. Their coerc…
By means of known constitutive relations for the D and H fields, which include both electric quadrupole and magnetic dipole terms, an eigenvalue theory is developed for electromagnetic wave propagation in an absorbing chiral medium. The theory allows the polarization eigenvectors to be determined, which the medium sup…
Pyrroles annulated with polycyclic aromatic compounds, which are expected to be good precursor molecules for low band gap polymers, are prepared by the reaction of aromatic nitro compounds with ethyl isocyanoacetate and the subsequent deethoxycarbonylation.
A saponite from Ballarat was intercalated with Al polycations by four different procedures involving different sources of polycations, and stabilised by calcination (pillared). 29Si and 27Al solid-state MNR of both the intercalated and the pillared samples have been measured and are discussed. 29Si NMR leads us to pro…
Two residues are known to play important catalytic roles in fatty acyl-thioester hydrolase, thioesterase II: Ser-101, the site of a covalent acyl-enzyme intermediate, and His-237 which is within hydrogen bonding distance of Ser-101 and facilitates catalysis by increasing the nucleophilicity of this residue. In this st…
Ionic conductivity in ferroelectric oxides having the perovskite structure is reviewed. Depending on the compound, doping levels, and equilibration conditions, ionic transport numbers approaching unity have been observed under equilibium conditions. The ionic conductivity decreases with decreasing temperature with an…
LCSL
The phase field model for free boundaries consists of a system of parabolic differential equations in which the variables represent a phase (or “order”) parameter and temperature, respectively. The parameters in the equations are related directly to the physical observables including the interfacial width $\epsilon $,…
Sulfonated indolinespirobenzopyran (SP–SO3–) was intercalated into the Mg/Al or Zn/Al layered double hydroxides (LDHs) in the presence of toluene-p-sulfonic acid (PTS). The new intercalates exhibited reversible photoisomerization between SP–SO3– and merocyanine (MC). The presence of PTS was critical for the reversible…
In a project devoted to the elimination of toxic materials in methods of corrosion protection, a surface modification process has been developed to improve the pitting resistance of high copper aluminium alloys such as 2024 and 7075 without the use of chromates. This process involves immersion in boiling Ce(NO3)3, ano…
Ti–Ni shape memory alloy thin films were deposited using an RF magnetron sputtering apparatus. The as-sputtered films were heat-treated in order to crystallize and memorize. After the heat treatment, the shape memory characteristics have been investigated using DSC and thermomechanical tests. Upon cooling the thin fil…
Contents: A tutorial review of radioisotope power systems (R.G. Lange and E.F. Mastal). Summary of space nuclear reactor power systems 1983- 1992 (D. Buden). Silicon-germanium: an overview of recent developments (C.B. Vining and J.P Fleurial). Review of thermionic technology 1983- 1992 (R.C. Dahlberg et al.). Space nu…
Abstract The acoustic and dielectric properties of different glasses at audio frequencies and temperatures below 1 K have been investigated with the vibrating reed and a capacitance bridge technique. We found the temperature dependence of the absorption of vitreous silica (Suprasil W) to agree with the predictions of…
The severely distorted conformation adopted by the uncomplexed TRIMEB molecule in the solid state is attended by ring-inversion of one of the seven methylglucose residues.
$^{57}\mathrm{Fe}$ M\"ossbauer measurements show that the ${\mathit{T}}_{\mathit{c}}$ of 〈12〉-nm particles of ${\mathrm{MnFe}}_{2}$${\mathrm{O}}_{4}$ is higher than that of the 〈33〉-nm particles, which exhibit the bulk ${\mathit{T}}_{\mathit{c}}$ value (573 K). The $^{57}\mathrm{Fe}$ isomer shift as well as the intern…