Materials Literature
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We report on syntheses and electron transport properties of polycrystalline samples of diborides (AB2) with different transition metals atoms (A=Zr,Nb,Ta). The temperature dependence of resistivity, ρ(T), and ac susceptibility of these samples reveal superconducting transition of ZrB2 with Tc=5.5 K, while NbB2 and TaB…
Atomistic computations of the Peierls stress in fcc metals are relatively scarce. By way of contrast, there are many more atomistic computations for bcc metals, as well as mixed discrete-continuum computations of the Peierls-Nabarro type for fcc metals. One of the reasons for this is the low Peierls stresses in fcc me…
The Raman spectra of ${\mathrm{PbZr}}_{1\ensuremath{-}x}{\mathrm{Ti}}_{x}{\mathrm{O}}_{3}$ ceramics with titanium concentration varying between $x=0.40$ and 0.60 were measured at 7 K. By observing the concentration-frequency dependence of the vibrational modes, we identified the boundaries among the rhombohedral, mono…
Superconductivity and structural properties of Mg1-xAlxB2 materials have been systematically investigated. Evident modifications in both superconductivity and microstructure are identified to originate from the Al ordering along the c-axis direction. The resultant superstructure phase has an optimal composition of MgA…
The growth of multilayers made from a combination of a weak polyacid and a strongly dissociated polycation is studied as a function of salt concentration and molecular weight. Film thickness reaches a maximum at around 0.3 M salt and then decreases quickly. Preformed multilayers are shown to decompose rapidly and, for…
A revised crystal structure for mercerized cellulose based on high-resolution synchrotron X-ray data collected from ramie fibers is reported (space group P2(1), a = 8.10(3) A, b = 9.03(3) A, c = 10.31(5) A, gamma = 117.10(5) degrees; 751 reflections in 304 composite spots; theta < 21.11 degrees; lambda = 0.7208 A; LAL…
Einem Karussell ähnelt die Struktur der Titelverbindung [1⋅2 Py] (siehe Bild), der ersten Verbindung eines neuen Strukturtyps, die durch hochselektive Kondensationsreaktionen aus dem ebenfalls neuartigen [Fe(C5H4GaMe2)2] hergestellt wurde. Als Zwischenprodukt bildet sich das erste galliumverbrückte [m.m]Ferrocenophan…
Sensitised excitation of the DMN[3]DCME donor[bridge]acceptor system allows population of a triplet CT state with a microsecond lifetime in polar solvents. This is more than five orders of magnitude longer than the lifetime of the corresponding singlet CT state which is populated exclusively upon direct excitation. Th…
Das Wildtyp-Protein denaturiert unter Bedingungen, bei denen die Sekundär- und Tertiärstruktur der fluorierten Variante stabil bleiben. Dies ist auf den Einbau von 5′,5′,5′-Trifluorleucin 2 anstelle von Leucin 1 in ein Leucin-Reißverschluss-Protein bei der Biosynthese von E. coli zurückzuführen. Fluorierung des hydrop…
Without requiring chelation by sensitizers, a method to detect lanthanides by multiphoton excitation is reported. This suggests the use of lanthanides as calcium analogues in multiphoton microscopy. The spectrum shows the normalized two-photon excitation emission spectra (λex = 796 nm) of Eu(3+) with a resolution of a…
Abstract The formation and physicochemical properties of polymer electrolytes strongly depend on the lattice energy of metal salts. An indirect but efficient way to estimate the lattice energy through the relationship between the heterolytic bond dissociation and lattice energies is proposed in this work. The heteroly…
A multitechnique approach has allowed the first experimental determination of single-ion anisotropies in a large iron(III)-oxo cluster, namely [NaFe6(OCH3)12(pmdbm)6ClO4 (1) in which Hpmdbm = 1,3-bis(4-methoxyphenyl)-1,3-propanedione. High-frequency EPR (HF-EPR). bulk susceptibility measurements, and high-field cantil…
Abstract The influence of poly(ether imide) (PEI) on the structural ordering process in heat setting from the preoriented state of poly(ethylene 2,6‐naphthalene dicarboxylate) (PEN)/PEI blend films was investigated with the two‐color online birefringence system. The addition of small amounts of noncrystallizable PEI e…
Certain triblock copolymer surfaces have beneficial blood contacting properties that remain unexplained from a mechanistic perspective. In this study, poly(caprolactone-block-dimethylsiloxane-block-caprolactone) (PCL-b-PDMS-b-PCL) surfaces are characterized by dynamic contact angle analysis, angle-resolved X-ray photo…
The dynamic structure factor $f(q,t)$ of suspensions of adhesive colloidal spheres has been characterized as a function of temperature over the volume fraction range $0.010<\ensuremath{\varphi}<0.075.$ Below a critical temperature that is volume fraction dependent, the suspensions underwent an abrupt, reversible…
on an Si substrate results in the formation of individual alumina nanotubes (ANTs). The picture shows an ANT with a length of 650 nm and internal and external diameters of 12 and 35 nm, respectively. Detailed studies by transmission electron microscopy revealed that the ANTs are completely detached cells of the porous…
Abstract The purpose of this article is to study the fast structural changes that take place during the deformation and heat setting of uniaxially preoriented poly(ethylene 2,6‐naphthalate) films. For this purpose, an online birefringence measurement system coupled with a heat‐setting oven was used. In the online bire…
Die Insertion einer Difluoroxymethylen-Brücke in die mesogene Kernstruktur einer auf Phenylcyclohexan basierenden Verbindung (siehe Bild) führt zu einer neuen Klasse von Flüssigkristallen, die eine überraschende und bislang beispiellose Verbesserung aller anwendungsrelevanten Eigenschaften aufweist. Eine neue Methode…
Abstract Oil palm fibers represent a very abundant and natural resource for raw materials that can be efficiently utilized as reinforcement in polymers. The sorption characteristics of two types of oil palm fibers—oil palm empty‐fruit‐bunch (OPEFB) fiber and oil palm mesocarp fiber‐in distilled water, mineral water, a…
We investigate the effect of anisotropy in grain boundary mobility on the dynamics, morphology, and topology of grain growth, using both analytical and numerical calculations on a generalized anisotropic phase field model. The dependence of the grain boundary mobility on both inclination and misorientation is included…