Materials Literature
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Heavily Cu + -doped amorphous PbCl 2 has been obtained by quench deposition of the mixture of PbCl 2 and CuCl. Upon crystallization, the large majority of Cu + ions aggregate to form CuCl precipitates embedded in the crystalline PbCl 2 matrix. The present experiment opens up the possibility of producing densely disper…
Tryptophan analogues with unique spectral and photophysical properties offer intrinsic fluorescent probes for studying peptide−protein and protein−protein interactions. Two benzannulated indole derivatives, benz[ f ]indole and 3-methylbenz[ f ]indole, were synthesized and their fluorescence was characterized. The abso…
The effects of a partial substitution of Mo, Ga, Si or Al, respectively, for Fe on the structure and magnetic properties of Nd 8.4 Fe 87.1 B 4.5 alloy prepared by mechanical alloying have been studied in detail. The addition of 1.1 at% Mo, Si or Ga results in the improvement of the intrinsic coercivity of the nanocomp…
N-Benzoyl-L-tyrosyl-p-aminobenzoic acid hydrolase (PPH, human meprin), a zinc-metalloendopeptidase of the astacin family, consists of two similar subunits. As well as in small-intestinal epithelial cells, the enzyme is found in lamina propria leucocytes, human cancer cells and colorectal cancer tissue, making it a pot…
Laser-ablated rhenium, ruthenium, and osmium atoms react with O 2 in excess neon and argon during condensation to form the MO 2 dioxide molecules as major products. The MO 3 trioxides with D 3 h symmetry, the (O 2 )MO 2 dioxide complexes with C 2 v symmetry, and the tetrahedral MO 4 (M = Ru, Os) molecules are formed o…
We study the liquid-glass transition of the Lennard-Jones binary mixture introduced by Kob and Andersen from a thermodynamic point of view. By means of the replica approach, translating the problem in the study of a molecular liquid, we study the phase transition due to the entropy crisis and we find that the Kauzmann…
Molecular structure, morphological characteristics and electrical conduction in syndiotactic polypropylene (sPP) are studied. sPP is found to be highly resistant to thermal oxidation. The crystallinity measured by the x-ray diffraction meter is very low and shows no significant change with annealing, compared with tha…
Irreversible adsorption/deposition processes are defined as processes in which, once adsorbed, the particles can neither desorb from nor diffuse along the surface. These processes are commonly encountered when macromolecules or colloidal particles deposit on solid surfaces. This article presents a general and unified…
Our recent study on the incorporation of Sn in the lattice of MgAl-layered double hydroxides (LDHs) indicated that about 30 atom % of Al 3+ could be isomorphously substituted by Sn 4+ to form a new MgAlSn ternary LDH. In the present study, similar NiAlSn- and CoAlSn-LDHs were synthesized by a coprecipitation method. T…
We studied the dynamics of spontaneously spreading drops of viscous liquids over several decades of time. We show that there exist at least two different time scale behaviors which are compatible with the recently proposed combined theory of spreading dynamics.
Novel bent-core (banana-shaped) liquid crystals without Schiff-base units have been synthesized and investigated by polarized light optical microscopy, differential scanning calorimetry, X-ray scattering, and electrooptical investigations. These molecules are 4-(4-alkylbenzoyloxy)benzoates and 4-(4-alkoxybenzoyloxy)be…
We have combined the original diffusion-limited aggregation model introduced by Witten and Sander with the surface thermodynamics of the growing solid aggregate. The theory is based on the consideration of the surface chemical potential as a thermodynamic function of the temperature and nearest-neighbor configuration.…
The coupling between the superconducting planes of YBa2Cu3O{7-δ}/ PrBa2Cu3O{7-δ} superlattices has been measured by c-axis transport. We show that only by changing the thickness of the superconducting YBa2Cu3O{7-δ} layers, it is possible to switch between quasi-particle and Josephson tunneling. From our data we deduce…
We have performed a theoretical study of the magnetic circular dichroism in the x-ray absorption spectra (XMCD) of the equiatomic CoPt and FePt ordered alloys as a function of the spin quantization axis. We found that the magnetization axis is along the [001] direction and the magneto-crystalline anisotropy energy (MC…
Several boron-modified polysilazanes of general type {B[C 2 H 4 Si(R)NH] 3 } n (C 2 H 4 = CHCH 3 or CH 2 CH 2 ) were synthesized and their thermal behavior studied. In contrast to the known derivatives with R = alkyl or aryl, we describe ceramic precursors in which the bulky moieties R are substituted with lower weigh…
Magnetron sputtering of transparent conductive oxides (zinc oxide, indium tin oxide, tin oxide) is a promising technique which allows the deposition of films at low temperatures with good optical and electronic properties. A special advantage is the scalability to large areas. The principles underlying magnetron sputt…
The crystal structures of Ca 2 (Fe 0.933 Al 0.067 ) 2 O 5 and Ca 2 (Fe 0.722 Ga 0.278 ) 2 O 5 have been determined from single crystals grown from a CaCl 2 flux. Both are isostructural with Ca 2 Fe 2 O 5 (C 2 F), belonging to space group Pnma. Lattice constants are a = 5.420(1) A, b = 14.743(3) A, c = 5.597(1) A and a…
Optical and photoemission experiments reveal unexpected spectral signatures of one-dimensional band insulators. In the model compound (NbSe (4))3I the optical conductivity decays as a power law sigma(1)(omega) approximately omega(-4.25) above a sharp gap edge. Photoemission observes both the valence and a shadow band,…
We have performed magnetic and transport measurements on La0.67Ca0.33MnO3 polycrystalline and partially melted samples. The magnetization and resistance decrease as sintering temperature is increased. The insulator-to-metal transition temperature is remarkably enhanced in the partially melted sample, enabling its poss…
The X-ray crystal structure of a reaction centre from Rhodobacter sphaeroides with a mutation of tyrosine M210 to tryptophan (YM210W) has been determined to a resolution of 2.5 A. Structural conservation is very good throughout the body of the protein, with the tryptophan side chain adopting a position in the mutant c…