We present a systematic study on the preparation, characteration and potential application of Fe3O4 and Fe3O4@SiO2 nanoparticles. Fe3O4 nanoparticles of controllable diameters were successfully synthesized by solvothermal system with tuning pH. The magnetic properties of nanoparticles were measured by vibration sample magnetometer. Fe3O4@ SiO2 nanoparticles were obtained via classic Stöber proc...

We report the first-of-its-kind, self-organized gate-stack heterostructure of Ge-dot/ SiO2/SiGe-shell on Si fabricated in a single step through the selective oxidation of a SiGe-nanopatterned pillar over a Si3N4 buffer layer on a Si substrate. Process-controlled tunability of the Ge-dot size (7.5–90 nm), the SiO2 thickness (3–4 nm), and the SiGeshell thickness (2–15 nm) have been demonstrated, ...

Soft x-ray photoelectron spectroscopy with synchrotron radiation was employed to study the valence-band offsets for the HfO2 /SiO2 /Si and HfO2 /SiOxNy /Si systems. We obtained a valence-band offset difference of 21.0560.1 eV between HfO2 ~in HfO2/15 Å SiO2 /Si! and SiO2 ~in 15 Å SiO2 /Si!. There is no measurable difference between the HfO2 valence-band maximum positions of the HfO2/10 Å SiOxNy...

Xerogels consisting of SiO2 and TiO2 were explored for controlled release of brilliant blue FCF (BBF). Both SiO2 and SiO2–TiO2 xerogels were prepared by way of sol–gel processing, and the BBF release behavior was compared. SiO2–TiO2 xerogels with varying TiO2 content were also studied and the BBF release behavior was determined for each SiO2–TiO2 xerogel. It was found that the release of BBF fr...

Recently, temperature compensation of surface and bulk acoustic wave (SAW/BAW) technologies has become a topic of interest due to strong demand on wideband filters with excellent temperature stability. Two types of techniques are studied extensively. One is the wafer bonding of a piezoelectric substrate with a support substrate, which have large Young's modulus and small thermal expansion coeff...

We tested whether amorphous SiO2-NPs and formylpeptide receptor (FPRs) agonists synergistically activate human monocytes and neutrophil polymorphonuclear granulocytes (PMNs). Peptide ligands specifically binding to FPR1 (f-MLP) and to FPR2 (MMK-1, WKYMVM and WKYMVm) human isoforms did not modify the associa‐ tion of SiO2-NPs to both cell types or their cytotoxic effects. Similarly, the extent o...

Silica nanoparticles (SiO2 NPs) cause oxidative stress in respiratory system. Meanwhile, human cells launch adaptive responses to overcome SiO2 NP toxicity. However, besides a few examples, the regulation of SiO2 NP-responsive proteins and their functions in SiO2 NP response remain largely unknown. In this study, we demonstrated that SiO2 NP induced the expression of follistatin (FST), a stress...

In this paper, MgB2 bulks were prepared with doped TiO2 nanoparticles surface-modified by 5-10% SiO2. Quantitative X-ray diffraction (XRD) analysis was performed to obtain the weight fraction of impurities using the Rietveld method. The effects of addition of TiO2/SiO2 nanoparticles on the critical temperature (Tc), the upper critical field (Hc2), and the irreversibility field (Hirr) as a funct...

Elevated temperature synthesis has been used to generate virtually defect free SiO2 sheathed crystalline silicon nanowires and silica (SiO2) nanospheres which can be agglomerated to wire-like configurations impregnated with crystalline silicon. The SiO2 passivated ~sheathed! crystalline silicon nanowires, generated with a modified approach using a heated Si–SiO2 mix, with their axes parallel to...

Planar waveguides of SiO2:TiO2 (multilayer structure) and SiO2:CeO2 (thick layer) were prepared onto commercial glass substrates using a sol-gel technique combined with dip-coating. These glassy coatings were structural characterised by Transmission Electron Microscopy (TEM) Energy Dispersive X-ray analysis and by Confocal Microscopy. Thicknesses of 1230 nm and 4,15 μm and refractive indices of...