Materials Literature
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We report the effect of Al substitution on the Mn site of the bilayered half doped manganite ${\mathrm{La}}_{1}{\mathrm{Sr}}_{2}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}$. This substitution dilutes the magnetically active Mn-O-Mn network without introducing an appreciable distortion in the lattice, and ionic considerations le…
A novel approach is presented for the large-scale fabrication of ordered TiO 2 nanobowl arrays. The process starts with a self-assembled monolayer of polystyrene spheres, which is used as a template for atomic layer deposition of a TiO 2 layer. After ion-milling, toluene-etching, and annealing of the TiO 2 -coated sph…
Here we demonstrate, for the first time experimentally, a nanopipette action for metals using multiwalled carbon nanotubes. The process relies on electromigration forces, created at high electron current densities, enabling the transport of material inside the hollow core of carbon nanotubes. In this way nanoparticles…
Two polymer chains that occupy equal volumes when covalently linked together at one end self-assemble into an alternating lamellar morphology that has a characteristic period dictated by the molecular weight. When such copolymers are confined within alumina membranes that have cylindrical pores with diameters comparab…
We demonstrate an enhancement in the thermopower of PbTe nanostructures with grain sizes on the order of $30--50\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, relative to bulk. The enhancement is similar in magnitude to that reported in the literature for $\mathrm{Pb}\mathrm{Te}∕\mathrm{Pb}{\mathrm{Se}}_{x}{\mathrm{Te}}_{1\…
The optimization of diamond films as valuable engineering materials for a wide variety of applications has required the development of robust methods for their characterization. Of the many methods used, Raman microscopy is perhaps the most valuable because it provides readily distinguishable signatures of each of the…
In Crystallization of Polymers, 2nd Edition, published in 2004, Leo Mandelkern provides a self-contained, comprehensive, and up-to-date treatment of polymer crystallization. Volume 2 of this edition provides an authoritative account of the kinetics and mechanisms of polymer crystallization, building from the equilibri…
Diatoms are unicellular algae with plastids acquired by secondary endosymbiosis. They are responsible for approximately 20% of global carbon fixation. We report the 34 million-base pair draft nuclear genome of the marine diatom Thalassiosira pseudonana and its 129 thousand-base pair plastid and 44 thousand-base pair m…
The novel concept of reverse flow operation with reactor side feeding is studied for selective oxidation of NH 3 to produce either N 2, N 2 O, or NO. During normal reverse flow operation, where the feeds are alternately introduced from either end of the reactor, the conversion is always lower when compared to steady s…
In situ time-resolved X-ray diffraction in combination with the Rietveld method was used to study the contraction/expansion behavior of a BaY faujasite zeolite during dehydration and NO 2 adsorption/desorption reactions. The adsorption of water and NO 2 molecules induced a significant contraction of the zeolite unit c…
A method for preparing carbon and SiC macroscopic beads using ion-exchange resins as a macrotemplate that determines the macroshape and the pore structure of the product materials is reported. First, silicates are ion-exchanged into the resins to prevent the resin from collapsing during subsequent carbonization and al…
We prepared disklike tris(4-alkylbutadiynylphenyl)-1,3,5-benzenetricarboxamide and tris[4-(4-alkyloxyphenyl)butadiynylphenyl]-1,3,5-benzenetricarboxamide, where three phenyl diacetylenic and diphenyl diacetylenic groups are connected to a benzene ring through amide linkages, respectively. The structures of self-assemb…
A systematic study on the structural properties and external morphologies of large-pore mesoporous organosilicas synthesized using triblock copolymer EO 20 PO 70 EO 20 as a template under low-acid conditions was carried out. By employing the characterization techniques of SAXS, FE-SEM, and physical adsorption of N 2 i…
We present the results of high-resolution photoluminescence and magneto-optical spectroscopy of selectively doped $\mathrm{Si}∕\mathrm{Si}:\mathrm{Er}$ nanolayer structures grown by sublimation molecular beam epitaxy method. We show that the annealing of such samples results in a preferential formation of a single typ…
We demonstrate that carbon nanotori constructed by either coalescing C 60 molecules along the 5-fold axis (incorporating pentagons and octagons) or by joining the ends of Haeckelite tubes (containing heptagons, hexagons, and pentagons) exhibit large magnetic moments when an external magnetic field is applied. In parti…
Distribution of the probability current and the probability density of wave packets was calculated for nanotubes and nanotube Y junctions by solving the three dimensional time-dependent Schr\"odinger equation for a jellium potential model of the scanning tunneling microscope (STM) tip-nanotube-support system. Four sys…
The reaction between [Pd(2)(dba)(3)] (dba = dibenzylideneacetone), tributylphosphine, and a bis(cycloalkeno)-1,4-diselenin leads to either a mononuclear diselenolene [Pd[SeC(R(1))=C(R(2))Se](PBu(3))(2)] or a dinuclear diselenolene [Pd(2)[SeC(R(1))=C(R(2))Se](2)(PBu(3))(2)] [R(1), R(2) = (CH(2))(n), n = 4, 5, 6] depend…
Models of photogeneration of charge carriers and structural regularities of the photoeffect are analyzed for homologous series of the main classes of photosensitive polymer semiconductors and their donor-acceptor complexes with different sensitizers. The relationship between the chemical structure of polymers and thei…
Frustration verstehen: Eine gezielte Beeinflussung der Struktur durch die Wahl des Templats machte neunkernige Metallräder mit {Cr8Ni}- oder {Cr7(VO)2}-Kernen zugänglich. Magnetismusstudien (siehe Bild) an einem dieser Räder ergaben ein Verhalten als magnetisches Möbius-Band. Diese ersten detaillierten Magnetismusstud…
Trockene Filme: Durch Elektrospinnen wurden Filme mit großen Wasserkontaktwinkeln (166.7°) und kleinen Gleitwinkeln (4.3°) hergestellt. Diese Filme zeigen eine ausgezeichnete superhydrophobe Cassie-Bereichs-Stabilität: Im Bild ist ein selbst nach uniaxialer Belastung mit 400 Pa nicht benetzender Wassertropfen zu sehen.