Materials Literature
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The spin, charge, and orbital ordering in ${R}_{0.5}{A}_{0.5}$MnO${}_{3}$ and ${R}_{0.5}{A}_{1.5}$MnO${}_{4}$ $(R$=rare earth, $A$=Sr, Ca) has been studied by means of unrestricted Hartree-Fock calculations on the multiband $p\ensuremath{-}d$ model. Since the superexchange interaction between the Mn${}^{3+}$ and Mn${}…
We study the effects of the degeneracy of the ${e}_{g}$ orbitals in perovskite transition-metal oxides in the limit of strong repulsive electron-electron interaction. The isospin field is introduced to describe the orbital degrees of freedom and is represented by the boson with a constraint. The dispersion of this bos…
Quantum chemical calculations by means of the semiempirical modified neglect of diatomic overlap and Austin model 1 (AM1) methods are presented for hexakis $(n$-alkoxy) triphenylene with $n=1$ and 4. The predicted molecular structures by the self-consistent electronic field are presented and discussed. The optimized g…
Abstract Organo‐soluble cellulose‐ p ‐toluenesulfonates (tosylates) with an insignificant incorporation of chlorodeoxy functions were prepared by reacting cellulose dissolved in N,N ‐dimethyl acetamide/LiCl and used as intermediates in the design of cellulosics with new, unusual molecular structures. Thus, the remaini…
Abstract Advanced evaluation techniques as Rietveld refinement applied to series of temperature resolved X‐ray diffraction measurements, provide an improved insight into the lattice dynamics. The transition paths of ammonium nitrate are clearly defined and coexisting phases are quantitatively determined. The curves fo…
Summary: Alcaligenes eutrophus was grown in continuous culture (34 °C, pH 6.8) under various conditions with respect to dilution rate, nutrient limitation and carbon substrate. Poly-3-hydroxybutyrate (PHB) content, the rate of PHB production ( q PHB ) and the rate of carbon substrate utilization ( q s ) during growth…
The winding process tends to promote yarn hairiness, a detrimental effect that can be significantly reduced by adding a properly arranged air-jet nozzle. This paper examines the mechanisms of hairiness reduction with an air jet during winding. The results indicate that the direction of the majority of protruding fiber…
Zinc hydroxystannate (ZHS), at levels of 2-5 phr, and the hydrated fillers, magnesium hydroxide (MH) and alumina trihydrate (ATH), at levels of 20–50 phr, are effective flame retardants and smoke suppressants for flexible PVC. Novel ZHS-coated hydrated fillers are found to exhibit markedly improved fire-retardant prop…
In order to determine the mechanisms of twin growth, a high-resolution electron microscopy study of the tip morphology in (1012) twin in zinc has been carried out. In a new model presented here, the twin tip is described as a series of (1012)//(1012) step faces, containing one or more interfacial dislocations. They ar…
Thin films of ClAlPc of 100 - 300 nm thickness were sublimed onto glass substrates in high vacuum. Studies of the molecular structure of ClAlPc have been made using films deposited at various temperatures and films annealed after deposition at room temperature. The optical properties in both monoclinic and triclinic f…
Examining the effect of nonhydrostaticity on the shape of x-ray powder diffraction lines shows that a uniaxial stress field, as is generated in opposed-anvil type high-pressure apparatuses, can result in lines being split or having an asymmetric shape. The distribution of local stresses, generated by mismatches in sha…
1,4,7,10-Tetrathia (12-crown-4)-bridged new polymeric phthalocyanines 9 and 10 have been synthesized by the reaction of tetracyanodibenzo[1,4,7,10-tetrathia (12-crown-4)] in the presence of a strong organic base or Zn ( OAc ) 2 respectively. Furthermore, 1,4,7,10-tetrathia (12-crown-4)-linked peripherally octa-substit…
Abstract Reaction of cellulose (1) with the bulky thexyldimethylchlorosilane (TDMSCl) leads to regioselectively functionalized silyl celluloses with degree of substitution (DS) up to 2. Uniform 6‐O‐thexyldimethylsilyl cellulose (2) was obtained in ammonia‐saturated aprotic dipolar media, which was unexpected in a hete…
Chemical oxidation of (TMP)Mn(III)(Cl) (TMP = the tetramesitylporphyrinato dianion) by Fe(ClO(4))(3) leads to the porphyrin-oxidized product (TMP(*)(+))Mn(III)(ClO(4))(2). Magnetic measurements and EPR spectroscopy show that the total spin of the complex changes from S = (5)/(2) at high temperature to S = (3)/(2) at l…
We use the Preisach model of magnetic hysteresis to model the inductance in a series LCR circuit. By introducing a hysteresis parameter into the Preisach functions used, we are able to continuously vary the width of the hysteresis loop and thereby investigate the effects of magnetic hysteresis on the circuit's behavio…
Cyclic tension and compression testing has revealed that cracking behavior in structural steel subjected to plastic strain reversals is transitional from a fatigue to a ductile mode with the elevation of strain amplitude. The transition can be identified by the plastic strain accumulation pattern, the fractographic ap…
The mechanical properties of three grades of PMMA, one linear and two crosslinked, are investigated in tension below and above the glass transition temperature. It is found that strain-hardening decreases gradually with temperature in the glassy state, but keeps a significant value in the rubbery state. The results ar…
Solutions (1−5 wt %) of ultrahigh-molecular-weight atactic poly(acrylonitrile) (UHMW-PAN) in N, N‘ -dimethylformamide were crystallized to gel by quenching from 100 to 0 °C. The dried gel films exhibited poor ductility on straight tensile draw. However, they were ductile on solid-state coextrusion to an extrusion draw…
Catalytic properties of Pt−Ge intermetallic compounds, Pt 3 Ge, Pt 2 Ge, and PtGe, were studied for the H 2 −D 2 equilibration and the hydrogenation of 1,3-butadiene. Powdered Pt, Ge, and the Pt−Ge intermetallic compounds were treated with H 2 at 873 K to reduce their surface oxidized in air. XPS spectra measured afte…
The isothermal change of the magnetic entropy of a magnetically ordered material upon application of external magnetic field can be calculated from the temperature and field dependence of the magnetization or of the specific heat. The adiabatic temperature change, i.e., the magnetocaloric effect (MCE) can be measured…