Materials Literature
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We have observed the unoccupied partial Pd 4d density of states in Cu-Pd alloys by bremsstrahlung isochromat spectroscopy (BIS). It shows the filling of the Pd 4d band upon alloying, which is consistent with the Pd ${\mathit{L}}_{\mathrm{III}}$ absorption spectroscopy measurements. We have also determined the total ch…
Addition of germanium to the Se–Te alloy causes structural changes which modify the band structure and hence the electrical properties of the Se–Te alloy. In the present work, electrical, optical, and structural properties of Se–Te–Ge have been studied. The activation energies calculated from the dc resistivity measur…
The considerable industrial interest in the qualitative and quantitative production of polyhydroxyalkanoates in microorganisms has led to the characterization of those synthesized in the nitrogen-fixing bacteria Azospirillum brasilense and Azotobacter paspali. In contrast to some other bacterial species, Azospirillum…
Neutron diffraction has been used to determine the location and concentration of C in Nd2Fe17 and in a Si substituted alloy. The results indicate that two carbide phases exist. One contains nearly three C atoms per formula unit, while the other has a much lower concentration. The high C phase contains C only on the 9e…
Large photoinduced absorption is observed in free-standing porous-silicon films in the spectral range from 1.1 to 2.5 eV by using a femtosecond pump-and-probe technique. The measured nonlinear transmission spectra have a very fast component with initial decay on the subpicosecond time scale. The spectral structure and…
Selected tensor property coefficients of the nonlinear optical crystal LiB3O5 are reported. The full set of pyroelectric, dielectric, and thermal expansion coefficients were measured as a function of temperature. The five independent piezoelectric coefficients, the full set of electromechanical coupling coefficients,…
Valerate and other short-chain, uneven-length fatty acids promoted the formation of the polyhydroxyalkanoate (PHA) copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in Azotobacter vinelandii UWD growing in glucose medium. The uptake of valerate was inducible, being repressed by acetate but not by glucose. A likel…
Poly(hydroxyalkanoates) form biodegradable composites when blended with starch granules but the mechanical properties are poor. Unlike starch granules, thermoplastic starch is a flexible material that can be reprocessed at elevated temperatures. Mixing thermoplastic starch with poly(hydroxybutyrate-co-12%-hydroxyvaler…
The adsorption of Li on the Si(100) surface has been studied over a wide coverage range with high-resolution core-level spectroscopy. The dimer structure of the clean surface was preserved up to a coverage corresponding to \ensuremath{\Delta}\ensuremath{\varphi}=-1.8 eV. Above this coverage intermixing and silicide gr…
Ein kettensteifes molekulares Rückgrat mit hydrophilen und hydrophoben Substituenten zeichnet das makrocyclische Amphiphil 1 aus, das im Grammaßstab zugänglich ist. Wie die Kristallstrukturanalyse von 1 nach Umkristallisieren aus Pyridin zeigt, weisen die polaren Phenoxygruppen nach außen, und der Ring bildet einen hy…
In vitro preparation of long side chain poly(3-hydroxyalkanoate) artificial granule suspensions that mimic the "as biosynthesized" inclusions in vivo is reported. Elastomeric poly(3-hydroxyalkanoate) can be made into an aqueous suspension of noncrystalline, submicron-sized particles. Light-scattering measurements on t…
The first-principles orthogonalized linear combination of atomic orbitals method has been applied to calculate the electronic structures, total energies, and optical properties of four boron-rich compounds: ${\mathrm{B}}_{12}$${\mathrm{As}}_{2}$, ${\mathrm{B}}_{12}$${\mathrm{P}}_{2}$, ${\mathrm{B}}_{11}$C(CBC) (or ${\…
A two-stage culture method employing Lactococcus lactis IO-1 and Alcaligenes eutrophus was developed for the production of polyhydroxyalkanoic acid (PHA) from xylose via L-lactate. In this culture method, xylose was converted into L-lactic acid and acetic acid by a culture of L. lactis IO-1, and the organic acids were…
We report on far-infrared reflection measurements on Si:P in the temperature range between 10 and 300 K for doping concentrations between N=3.4\ifmmode\times\else\texttimes\fi{}${10}^{17}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$ and 7.4\ifmmode\times\else\texttimes\fi{}${10}^{19}$ ${\mathrm{cm}}^{\mathrm{\ensuremat…
Large variations in the broad-band reflectance (\ensuremath{\sim}3.4% per reflection at 5000 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$) were observed in the multiple-internal-reflection infrared spectrum of a diamond (110) surface upon surface chemical modification. Larger changes in reflectivity were observed for s…
Metabolites associated with the poly(3-hydroxybutyrate) (PHB) biosynthetic pathway in Alcaligenes eutrophus were measured to gain an insight into the regulation of PHB synthesis in vivo. Alcaligenes eutrophus was grown in carbon-limited chemostat culture to provide bacteria producing negligible PHB, and in nitrogen-li…
The problem of deriving from microscopic theory a Ginzburg-Landau free-energy functional to describe the Peierls or charge-density-wave transition in quasi-one-dimensional materials is considered. Particular attention is given to how the thermal lattice motion affects the electronic states. Near the transition tempera…
Novel functional poly(β-hydroxyalkanoates), PHAs, with hyperpolarizable side groups were prepared. Pseudomonas oleovorans ATCC 29347 and Pseudomonas putida KT 2442 were selected as biocatalysts. These organisms were first grown on citrate (40 mM) before polymer formation was studied in a second stage. The carbon sourc…
The isolation of poly(3-hydroxyoctanoic acid)- and poly(6-hydroxyhexanoic acid)-degrading bacteria yielded 28 strains with abilities to degrade various polymers. The most versatile strains hydrolyzed five different polyesters comprising short chain length and medium chain length poly(hydroxyalkanoates). The new isolat…
Using a recently developed method, we show here that solvent effects on the first molecular hyperpolarizabilities of push-pull polyenes can be predicted by evaluation of the relaxation contribution βr to the hyperpolarizability from vibrational infrared and Raman intensities and vibrational frequencies. The molecules…