A multiple internal transmission (MIT) technique was used for infrared (IR) spectroscopic investigations during annealing of the interfaces in room temperature Si-Si bonded wafers with different ...chemical pre-treatments. The evolution with annealing temperature of the chemical species at the interface are used to explain the bonding mechanism of Si wafers in the temperature range of 30-400/spl deg/C.
Hard carbon thin films were synthesized on Si (100) and quartz substrates by the Pulsed Laser Deposition (PLD) technique in vacuum or methane ambient to study their suitability for applications ...requiring high mechanical resistance. The deposited films' surface morphology was investigated by scanning electron microscopy, crystalline status by X-ray diffraction, packing and density by X-ray reflectivity, chemical bonding by Raman and X-ray photoelectron spectroscopy, adherence by "pull-out" measurements and mechanical properties by nanoindentation tests. Films synthesized in vacuum were a-C DLC type, while films synthesized in methane were categorized as a-C:H. The majority of PLD films consisted of two layers: one low density layer towards the surface and a higher density layer in contact with the substrate. The deposition gas pressure played a crucial role on films thickness, component layers thickness ratio, structure and mechanical properties. The films were smooth, amorphous and composed of a mixture of sp3-sp2 carbon, with sp3 content ranging between 50% and 90%. The thickness and density of the two constituent layers of a film directly determined its mechanical properties.
Chitin of poriferan origin is a unique and thermostable biological material. It also represents an example of a renewable materials source due to the high regeneration ability of Aplysinasponges ...under marine ranching conditions. Chitinous scaffolds isolated from the skeleton of the marine sponge Aplysina aerophobawere used as a template for the in vitroformation of Fe sub(2)O sub(3) under conditions (pH similar to 1.5, 90 degree C) which are extreme for biological materials. Novel chitin-Fe sub(2)O sub(3) three dimensional composites, which have been prepared for the first time using hydrothermal synthesis, were thoroughly characterized using numerous analytical methods including Raman spectroscopy, XPS, XRD, electron diffraction and HR-TEM. We demonstrate the growth of uniform Fe sub(2)O sub(3) nanocrystals into the nanostructured chitin substrate and propose a possible mechanism of chitin-hematite interactions. Moreover, we show that composites made of sponge chitin-Fe sub(2)O sub(3) hybrid materials with active carbon can be successfully used as electrode materials for electrochemical capacitors.
Chitin of poriferan origin is a unique and thermostable biological material. It also represents an example of a renewable materials source due to the high regeneration ability of
Aplysina
sponges ...under marine ranching conditions. Chitinous scaffolds isolated from the skeleton of the marine sponge
Aplysina aerophoba
were used as a template for the
in vitro
formation of Fe
2
O
3
under conditions (pH ∼ 1.5, 90 °C) which are extreme for biological materials. Novel chitin-Fe
2
O
3
three dimensional composites, which have been prepared for the first time using hydrothermal synthesis, were thoroughly characterized using numerous analytical methods including Raman spectroscopy, XPS, XRD, electron diffraction and HR-TEM. We demonstrate the growth of uniform Fe
2
O
3
nanocrystals into the nanostructured chitin substrate and propose a possible mechanism of chitin-hematite interactions. Moreover, we show that composites made of sponge chitin-Fe
2
O
3
hybrid materials with active carbon can be successfully used as electrode materials for electrochemical capacitors.
Chitinous scaffolds isolated from the skeleton of marine sponge
Aplysina aerophoba
can be used as a template for the
in vitro
formation of hematite (Fe
2
O
3
) under conditions (pH ∼ 1.5, 90 °C), which are extreme for biological materials.
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