Materials Literature
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We have investigated the activation barriers and the intermediate paths of the transformation to cubic diamond and that to hexagonal diamond from graphite under pressure, allowing both atomic geometry and unit-cell shape to vary, in order to clarify the difference of the microscopic mechanisms between them. For this i…
Cuboid silsesquioxanes with appropriate side chains (see below; n = 4, 6, 11) provide a means of structuring soft matter with inorganic cores. These compounds combine material characteristics of polymer and low molecular mass liquid crystals.
The purpose of this work was to evaluate the effect of compositional modifications on the electrical properties of lead lanthanum zirconate stannate titanate (PLZST) ceramics, as well as to examine their electrically induced phasechange behavior. Variations in the Ti:Sn ratio were evaluated. Increased Ti 4+ content pr…
We present a neutron-scattering study of depletion interactions in a mixture of a hard-sphere-like colloid and a nonadsorbing polymer. By matching the scattering length density of the solvent with that of the polymer, we measured the partial structure factor ${S}_{c}(Q)$ for the colloidal particles. It is found that t…
An extensive experimental study has been conducted to examine the influence of ultraflne SiC particles on grain growth in A1 2 O 3 . Grain growth has been studied as a function of annealing time, particle volume fraction, and annealing temperature. The SiC particles reduce the grain‐growth rate of A1 2 O 3 by >3 order…
Porous silicon is emerging in micromachining technology as an excellent material for use as a sacrificial layer. This is largely due to the ease of fabrication and freedom of design it allows. The rate of pore formation is heavily dependent upon the doping type and concentration of the silicon, allowing patterned poro…
Structural aspects of the Bechgaard salts (TMTSF)2X and related 2:1 salts, mostly based on the sulfur donors TMTTF and BCPTTF as well as on the hybrid TMDTDSF donor, are considered in relationship with their physical properties. The basic structure of these salts is reviewed with a special emphasize on the dimerizatio…
Nutritional characteristics of the hyperthermophilic archaeon Thermococcus litoralis have been investigated with emphasis on the development of a sulfur-free, defined growth medium, analysis of an exocellular polysaccharide, and formation of a biofilm. An artificial-seawater-based medium, containing 16 amino acids, ad…
The size distribution of liposomes is often determined using freeze fracture, cryoelectron microscopy or dynamic light scattering. However, the resulting size distributions do not directly coincide owing to the different weighting of the techniques. We present several methods which correct for these effects and allow…
It has been reported that the silicate phase as well as the cross-linking of the polycarboxylic acid by aluminum and calcium ions played an important role in the hardening of glass-ionomer cement. The objective of this study was to investigate the structural change during hardening of the cements by means of infrared…
The effects of temperature (25–40°C), H2SO4 concentration (31–70% (w/v)) and the acid/substrate relationship (1–5 cm3 of H2SO4 per g−1 of cellulose) on the solubilization rate of microcrystalline cellulose and on the glucose production rate have been analysed. The solubilization process was by determining reducing gro…
Biofouling of equipment surfaces in the food industry is due initially to physico-chemical adhesion processes, and subsequently to the proliferation of microbes within an extracellular polymer matrix. Two physico-chemical theories can be applied to predict simple cases of bacterial adhesion. However, these models are…
High values of NOx reduction may be obtained with urea as a reducing agent and a standard SCR catalyst based on TiO2-WO3-V2O5. The process was carefully investigated for possible secondary emissions and it could be shown that urea-SCR does not lead to relevant emissions of nitrogen dioxide, nitrous oxide, hydrogen cya…
We describe two electrochemical self-assembly processes for producing highly ordered quasi-periodic arrays of quantum dots on a surface. The advantages of these techniques are: (i) they are `gentle' and do not cause radiation damage to nanostructures unlike beam lithography, (ii) they have high throughput and are amen…
Substrate topography in the micrometer range is reviewed as a modifier of the response of cultured cells and of biocompatibility when implanted into tissues. Characterization methods for substrate topography are discussed, including scanning electron microscopy, profilometry, laser scanning, and confocal microscopy. B…
A high catalytic activity towards alkene epoxidation is shown by titanium‐modified MCM41 mesoporous silicas if 2‐methyl‐1‐phenyl‐2‐propyl hydroperoxide (MPPH) is used as oxidant. This first example in which MPPH has been used as an efficient two‐electron oxidizing agent demonstrates that it is a competent replacement…
Collagen in tissues THE ROLE OF COLLAGENCollagen is the Inost abundant protein component of the extracellular matrix (ECM), and provides the insoluble fibres and microfibrils in this complex cOlnposite material.A key role for this collagenous network is to provide a scaffold for cell attachment and rnigration, as welI…
An ultrasonic pulse echo technique was employed to measure the single-crystal elastic constants and their temperature dependence in the vicinity of an intermediate phase transition at 265 K in a ${\mathrm{Ni}}_{2}$MnGa single crystal. The measured elastic constants at 300 K (in units of ${10}^{11}$ dyn/${\mathrm{cm}}^…
We present a dynamic light scattering study on the sol-gel transition of a suspension of disk-shaped colloidal particles in water. We obtain the static and fluctuating part of the scattered intensity, the fraction of frozen-in density fluctuations, and the intermediate scattering function from a local time-averaged me…
Abstract The effect of several chemical treatments, viz. organotitanate, zirconate, silane, and N‐substituted methacrylamide, on the properties of sisal fibers used as reinforcement in unsaturated polyester resin (∼50 vol%) was investigated. An improvement in the properties was observed when sisal fibers were modified…