Allenylsilanes reacted at room temperature in acetonitrile with Selectfluor, an electrophilic fluorinating reagent, to give secondary propargylic fluorides in moderate to good yields; mechanistically, a side-product resulting from a 1,2-silyl shift testifies to the presence of a cationic intermediate.

Germanium (Ge) nanocrystals had been synthesized by annealing co-sputtered SiO2-Ge in N2 and/or forming gas (90% N2 + 10% H2) at temperatures ranging from 700 to 1000°C from 15 to 60 min. It was concluded that the annealing ambient, temperature and time have a significant influence on the formation and evolution of the nanocrystals. We also showed that a careful selective etching of the anneale...

It is very interesting that magic electron affection promotes growth of nanocrystals due to nanoscale characteristics of electronic de Broglie wave which produces resonance to transfer energy to atoms. In our experiment, it was observed that silicon nanocrystals rapidly grow with irradiation of electron beam on amorphous silicon film prepared by pulsed laser deposition (PLD), and silicon nanocr...

Colloidal cubic silicon carbide (SiC) nanocrystals with an average diameter of 4.4 nm have been fabricated by anisotropic wet chemical etching of microsized cubic SiC powder. Fourier transform infrared spectra show that these cubic SiC nanocrystals contain carboxylic acid, SiH, CH, and CHx groups. UV/Vis absorption and photoluminescence (PL) spectroscopy clearly indicate that water and ethanol ...

In order to test recently predicted ballistic nanofriction (ultra-low drag and enhanced lubricity) of gold nanocrystals on graphite at high surface speeds, we use the quartz microbalance technique to measure the impact of deposition of gold nanocrystals on graphene. We analyze our measurements of changes in frequency and dissipation induced by nanocrystals using a framework developed for fricti...

Water-soluble hexagonal NaScF4:Yb/Er nanocrystals have been directly synthesized via a facile one-step hydrothermal route. The as-prepared nanocrystals were monodisperse and could form stable colloidal solutions in polar solvents, such as water and ethanol. The novel NaScF4:Yb/Er nanocrystals exhibited intrinsic intense red upconversion emission, in contrast to other lanthanide-doped fluoride n...

Hesperidin nanocrystals was generated by high pressure homogenization. The physicochemical properties of a spray dried hesperidin nanocrystals were investigated including to re-dispersion, crystalline state, kinetic solubility, dissolution velocity. Hesperidin nanosuspension with concentration of 10% (w/v) was dried by a Mini Spray-dryer B-190. Photon correlation spectroscopy (PCS) and laser di...

Here, we present a hot injection synthesis of colloidal Ag chalcogenide nanocrystals (Ag(2)Se, Ag(2)Te, and Ag(2)S) that resulted in exceptionally small nanocrystal sizes in the range between 2 and 4 nm. Ag chalcogenide nanocrystals exhibit band gap energies within the near-infrared spectral region, making these materials promising as environmentally benign alternatives to established infrared ...

The synthesised biobased calcium carbonate nanocrystals had demonstrated to be an effective carrier for delivery of anticancer drug doxorubicin (DOX). The use of these nanocrystals displayed high levels of selectivity and specificity in achieving effective cancer cell death without nonspecific toxicity. These results confirmed that DOX was intercalated into calcium carbonate nanocrystals at hig...

A thorough investigation of the challenging Pd-catalyzed fluorination of five-membered heteroaryl bromides is presented. Crystallographic studies and density functional theory (DFT) calculations suggest that the challenging step of this transformation is C-F reductive elimination of five-membered heteroaryl fluorides from Pd(II) complexes. On the basis of these studies, we have found that vario...