Materials Literature
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Morphology changes in etch pits formed on the (10 1 4) cleavage plane of calcite were induced by varying the ratio of [Ca 2+ ] to [CO 3 2 - ] in the bulk solution as well as through the addition of the crystal poison 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP). Three distinct morphologies were noted: symmetric rh…
The high photosensitivity of titaniumoxo phthalocyanines makes them suitable for application as charge generation materials, e.g., in photocopiers. The synthesis, photophysical, and photochemical properties of soluble titaniumoxo phthalocyanines containing alkyl and alkoxy substitutents (see Figure) in the periphery o…
Temperature and bias-field dependences of dielectric behaviour in the antiferroelectric liquid crystal, R-MHPOBC, were investigated (see also previous paper). There are mainly two relaxation modes in the SmC*alpha and SmC* phases: one behaves as the soft-mode, which shows significant slowing down in the SmA* and SmC*a…
Ferroelectric memory devices are subject to failure due to both a simple loss of retention or due to imprint. The difference between retention and imprint as described here depends on the test history of the device. A pulsed capacitor test has been devised to simulate the signal available to a typical memory cell afte…
Poly(D,L-lactide-co-1,3-trimethylene carbonate) (PLCA) has been synthesized by ring-opening polymerization of 1,3-trimethylene carbonate (CA) and D,L-lactide (LA) using stannous octoate as catalyst. The copolymers were characterized by 1H nuclear magnetic resonance (NMR), 13C NMR and differential scanning calorimetry.…
The diffraction characteristics of finite-number-of-periods (FNP) gratings are determined by using rigorous electromagnetic analysis based on the two-region formulation of the exact boundary element method. Gratings with 5, 9, 13, and 17 periods are analyzed and compared with infinite-number-of-periods (INP) gratings…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTPlastic Superconducting Polymer−NbSe2 NanocompositesHui-Lien Tsai, Jon L. Schindler, Carl R. Kannewurf, and Mercouri G. KanatzidisView Author Information Department of Chemistry and Center for Fundamental Materials Research Michigan State University East Lansing, Michi…
The basis set dependency of Al and Si isotropic chemical shieldings in Al 3+ ·6(H 2 O), [Al(OH) 4 ] 1- ·2(H 2 O), and tetramethylsilane have been calculated using the GIAO formalism. The Si chemical shielding changes substantially with the addition of extra d-functions; however, this influence is smaller than the effe…
Photochemical phase transition behavior of photochromic azobenzene liquid crystals (LCs) was explored by means of reflection-mode analysis. On pulse irradiation at 355 nm, which causes trans − cis isomerization of the azobenzene moiety, these LCs underwent nematic (N) to isotropic (I) phase transition in 100 μs as pro…
Dielectric properties of ceramic samples of Sr 1− x Pb x TiO 3 solid solutions for x varying from 0 to 0.3 have been studied. The ferroelectric phase transition in this system has been established to persist down to x =0.005. Within the x values of 0.002 to 0.05, the ferroelectric transition temperature is shown to fo…
Disorder broadening due to randomly distributed ${\mathrm{La}}^{3+}$ and ${\mathrm{A}}^{2+}$ (A=Ca,Sr,Ba) cations is combined with a virtual-crystal treatment of the average system to evaluate the effects on both majority and minority transport in the ferromagnetic ${\mathrm{La}}_{2\mathrm{/}3}$${\mathrm{A}}_{1\mathrm…
A thorough study of the M{umlt o}ssbauer spectra (MS) of a lightly iron doped (2{percent}) polycrystalline La{sub 0.75}Ca{sub 0.25}MnO{sub 3} compound has been carried out from T=4.2 K up to 300 K. The MS for T{gt}T{sub c} and at T=4.2 K show one component. The corresponding hyperfine parameters are compatible with S=…
We demonstrate that transverse magnetoresistance is a nonanalytical function of the magnetic field, ${\mathrm{\ensuremath{\rho}}}_{\mathrm{\ensuremath{\perp}}}$(H)\ensuremath{\sim}|H${\mathrm{|}}^{1\mathrm{/}2}$, if a magnetic field is parallel to the plane of anisotropy and normal to the Fermi surface at an inflectio…
The synthesis of phosphino-terminated dendrimers is described up to the tenth generation, which possess more than 3000 phosphino groups (3-[G'(10)()]). Several complexation reactions of these dendrimers toward various low oxidation states transition metal derivatives have been carried out, up to generation 5 for iron…
A series of ruthenium(II) porphyrin dimers and trimers (carbonyl dimers, 1-4; carbonyl trimers, 5-7, bis(pyridyl) trimers, 8-10), having axial or bridging porphyrin ligands, were synthesized and characterized by (1)H NMR and IR spectroscopy and mass spectrometry. An X-ray structural determination of Ru(II)(OEP)(CO)(H(…
The photopolymer material of poly(vinyl cinnamate) (PVCi) has been used to investigate the contribution of the anisotropic van der Waals force to the azimuthal anchoring energy in a pentyl cyanobiphenyl (5CB)/PVCi system. The optical anisotropy of a PVCi film is precisely controlled by varying the exposure time of lin…
Neutron and synchrotron X-ray powder diffraction techniques have been used to refine the crystal and magnetic structures of the n = 2 Ruddlesden−Popper (RP) system Sr 2 LaMn 2 O 7 . The sample is shown to be biphasic, although both phases are of the RP type and have similar structural parameters. The majority phase (8…
The equation traditionally used to interpret temperature programmed desorption (TPD) spectra, the Polanyi–Wigner equation, does not contain explicitly the coverage and temperature dependence necessary to predict TPD spectra in several important systems including CO–Ni(111). Herein, the statistical rate theory (SRT) ap…
Abstract The melting of poly(ethylene terephthalate) is analyzed by quasi‐isothermal, temperature‐modulated differential scanning calorimetry. The measurement is done by sinusoidally changing the temperature in the melting range (± 1.0 K). In the melting range a small portion of the sample melts reversibly. This obser…
It is argued that a pulsating acoustically levitated bubble cannot possibly maintain a spherical shape. A jet forms during compression, and the sound amplitude such that the jet first strikes the other side of the bubble with sufficient energy is hypothesized to be the threshold for sonoluminescence. It is proposed th…