Materials Literature
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Traditionally, studies on soil organic matter (SOM) begin with the extraction of SOM from soils, its fractionation into humic acid, fulvic acid, and humin, followed by de-ashing of each fraction. These are tedious, laborious and inefficient procedures that do not provide any chemical information on these materials. In…
Conductivity and Hall experiments are performed on hydrogenated poly-CVD, atomically flat homoepitaxially grown Ib and natural type IIa diamond layers in the regime 0.34 to 400 K. For all experiments hole transport is detected with sheet resistivities at room temperature in the range 104 to 105 Ω/□. We introduce a tra…
Hydrogen distribution in multipass submerged arc weld metal has been measured and analysed. The measurement of initial hydrogen content in a molten pool by obtaining samples directly from the pool shows that the effect of dilution on the initial hydrogen content can be neglected. The transient hydrogen distribution in…
We report a detailed study of the exchange interactions in the neutral Mn acceptor, A0, and excitons bound to Mn acceptors, A0X, in bulk GaAs. By means of spin-flip Raman scattering we measured the constant of antiferromagnetic exchange interaction between valence band holes and electrons in the inner Mn shell, deform…
Shows how observations (1993‐1999) and on‐site and laboratory measurements (1993‐1996) have made it possible to define certain prevalent parameters concerning AC corrosion risks. These are from the evaluation and prevention of AC corrosion risks as practised by Gaz de France.
Chitin was extracted from locally collected shrimp shells. Chitosan was produced by alkali deacetylation of chitin. Poly(DEAEMA)‐chitosan‐graft‐copolymer, poly(COOH)‐chitosan‐graft‐copolymer, poly(V‐OH)‐chitosan‐graft‐copolymer, and carboxymethyl‐chitosan were prepared. The extent of the preparation reactions was expr…
A phase diagram in the parameter space of temperature and blend composition that contains order−disorder transition (ODT) and thermoreversible macrophase separation between constituent copolymers was constructed for binary blends of polystyrene- block -polyisoprene (PS−PI) copolymers. The constituent copolymers, desig…
Abstract Raman scattering investigations on triphenyl phosphite, performed in both the low‐ and high‐wavenumber ranges, provide a detailed description of the glacial state. The latter can be described as a two‐phase (amorphous–nanocrystalline) system if it is prepared by isothermal aging in the 210–222 K temperature r…
Nanocrystalline two-phase NdFeB+α-Fe material was prepared by milling techniques and subsequent heat treatment. These isotropic exchange-coupled powders show excellent hard magnetic properties with enhanced remanences up to 1.20 T and energy densities (BH)max around 150 kJ/m3. The performance is based on (i) the use o…
Diamond is a very simple crystalline system, and we would expect that the effects of radiation damage should be easily understood. As an example of its simplicity, we note that diamond contains only one species of atom, and we show that the effects of isotopic substitution at the self-interstitial can be understood qu…
The structure of Cu/Cu 2 O multilayers fabricated by nonlinear electrochemical deposition has been tuned in two ways: electrochemically, by alteration of the deposition current, and by in-situ illumination during deposition. By choosing the current the thickness of the layers can be controlled, and by choosing the ill…
Millions of acres of land, formerly and currently used for military activities are potentially contaminated by surface and buried unexplored ordnance (UXO). Surface and buried UXO exists at hundreds of sites with diverse geologic and environmental conditions. UXO exists from the surface to depths as great as 10 m and…
Abstract It is shown that polytypes or stacking sequences of cronstedtite, an Fe-bearing trioctahedral 1:1 phyllosilicate, can be determined using near-atomic high-resolution transmission electron microscopy (HRTEM). By viewing along the [010], [310] and directions (orthohexagonal indexing), the four groups of the sta…
Homogeneous metallocene catalysts for the polyolefin production show compared with conventional Ziegler systems remarkable advantages, like the possibilities to regulate the microstructure leading to optimized polymer properties. However, for industrial application it is necessary to immobilize the metallocenes on a h…
The electrical resistivity, magnetization, and magnetoresistance effect have been studied on a series of Zn-doped polycrystalline samples Fe1−xZnxCr2S4 (0⩽x⩽1) with a spinel structure over a wide range of composition and temperature. It is found that the magnetism and magnetoresistance ratio are anomalous, which do no…
The atomic structure of the {111} diamond face after oxygen--water-vapor etching is determined using x-ray scattering. We find that a single dangling bond diamond {111} surface model, terminated by a full monolayer of $---\mathrm{OH}$ fits our data best. To explain the measurements it is necessary to add an ordered wa…
The plume generated by a pulsed XeCl laser from a novel nanostructured YBaCuO target (n target) is investigated by methods of optical emission spectroscopy and atomic force microscopy. While the spectral positions of the emission lines are the same, stronger line intensities, pertinent to higher kinetic energy of the…
A simple model of charge ordering is considered. It is explicitly shown that at any deviation from half-filling (n ≠1/2), the system is unstable with respect to the phase separation into the charge ordered regions with n =1/2 and the metallic regions with a smaller electron or hole density. A possible structure of thi…
A recombinant strain of Salmonella enterica serovar Typhimurium (mutant in propionate-activation activity) was metabolically engineered to control the composition of poly(3-hydroxybutyrate-co-3-hydroxy- valerate) (PHBV), a polyhydroxyalkanoate copolymer with commercially desirable properties. A gene (prpE) encoding pr…
Two polycrystalline samples of CoFe 2 O 4 were prepared by slow cooling and quenching and studied using Mössbauer spectroscopy and X-ray diffraction. The crystals were found to have a cubic spinel structure with the lattice constants of the slowly cooled sample being a 0 =8.381 Å and the quenched sample being a 0 =8.3…