Silica-based thulium-doped fiber devices operating around 810 nm would extend the spectral range covered by highpower fiber devices. Using a comprehensive numerical model of the fiber we have shown that efficient lasing at 810 nm can be achieved for specific ranges of the laser cavity parameters in silica-based thulium-doped fibers with enhanced 3 H4 lifetime up to 58 !s as measured in our high...

During evolution, living organisms have learned to design biomolecules exhibiting self-assembly properties to build-up materials with complex organizations. This is particularly evidenced by the delicate siliceous structures of diatoms and sponges. These structures have been considered as inspiration sources for the preparation of nanoscale and nanostructured silica-based materials templated by...

The most commonly used protocol of the RNA isolation, the guanidine thiocyanate method, was unsuitable for recalcitrant plant tissues containing a large amount of storage proteins and secondary metabolites. We demonstrated that RNA could bind to the silica particles, which have been used successfully in DNA isolation from various sources, under a high concentration of NaCl in the presence of et...

Mesoporous layers of silica are of interest for many optical applications, including the creation of devices ranging from optical sensors to laser sources with promising characteristics. Their optical characterization goes through the interpretation of measurements. We propose to give experimental results of reflectance and scattering measurements concerning mesoporous layers of silica deposite...

Silicosis, an interstitial lung disease caused by the inhalation of crystalline silica powder, despite being one of the oldest occupational diseases, continues being a cause of morbidity and mortality all over the world. The World Health Organisation and the International Labour Organisation (OMS/ILO), aware of the current problem, have designed the World Programme for the Elimination of Silico...

The generation of wavelengths above 3 μm by nonlinear processes in short silica photonic crystal fibers is investigated numerically. It was found that wavelengths in the 3-3.5 μm range may be generated quite efficiently in centimeter-long fiber pieces when pumping with femtosecond pulses in the 1.55-2 μm range. Wavelengths in the range of 3.5-4 μm can in principle be generated, but these requir...

A new route was recently proposed to modify some spectroscopic properties of rare-earth ions in silica-based fibers. We had shown the incorporation of erbium ions in amorphous dielectric nanoparticles, grown in fiber preforms. Here we present the achieved stabilization of nanometric erbium-doped dielectric nanoparticles within the core of silica fibers. We present the nanoparticle dimensional c...

Pre-shaped mesoporous amorphous rice husk ash (RHA) and MCM-41 derived from RHA as a silica source were transformed into MFI-type zeolites using two different structure-directing agents. Tetrapropylammonium hydroxide (TPAOH) was utilized as an alkali source for silica dissolution and structure control during the direct transformation of RHA into zeolite. A monopropylamine (PA)-containing alkali...

The introduction of nanoparticles into seed germination and seedling growth of plants might have a significant impact and thus, it can be used for agricultural applications for better growth and yield. The purpose of this study was to compare the effects of silica and silver nanoparticles on seed germination and early growth traits as well as percent and rate of germination, root length, shoot ...