Most of the World’s large tungsten deposits are genetically related to fluorine-rich granitic magmas, their ores contain fluorine minerals, such as fluorite and topaz, host rocks have commonly undergone metasomatism form greisens. In view this evidence that ore fluids enriched in fluorine, potential for fluoride stable complexes with hard acids (e.g., W6+), we investigated solubility speciation...

Molecular architecture in nanoscale spaces can lead to selective chemical interactions and separation of species with similar sizes and functionality. Substrate specific sorbent chemistry is well known through highly crystalline ordered structures such as zeolites, metal organic frameworks and widely available nanoporous carbons. Size and charge-dependent separation of aqueous molecular contami...

We report the first spectroscopic evidence for a [C-F-C]+ fluoronium ion in solution. Extensive NMR studies (19 F, 1 H, 13 C) characterize a symmetric cage-like species in which fluorine exhibits substantial covalent bonding to each of the two carbon atoms involved in the three-center interaction. Experimental NMR data comport well with calculated values to lend credence to the structural assig...

We have synthesized a molecule containing a close interaction between a C F bond and the p–orbitals of a ketone carbonyl group. Our studies have revealed that there is a combination of attractive and repulsive forces at play: the ketone’s IR stretching mode is blue-shifted, the carbonyl is bent away from the fluorine atom, and electron deformation density maps show some significant distortion o...

Introduction Perfluorocarbon (PFC) emulsions have been widely used for cell tracking studies [1,2] and many other biological applications [3]. In contrast to conventional H contrast agents, F markers provide unambiguous signal in vivo due to the low natural abundance of fluorine in living organisms. Furthermore, fluorine markers can possess a unique spectral signal, a further advantage of F MR....

This paper describes the results of using the GEC reference cell as a reactive ion etcher. Silicon wafers with layers of polysilicon and silicon dioxide on crystaline silicon patterned with photoresist have been investigated with fluorine and chlorine chemistries. Scanning electron microscopy (SEM), profilometry, and refraction techniques were used to determine the etch parameters such as etch ...

Here, we describe an improved system for protein crystallization based on heterogeneous nucleation using fluorinated layered silicate. In addition, we also investigated the mechanism of nucleation on the silicate surface. Crystallization of lysozyme using silicates with different chemical compositions indicated that fluorosilicates promoted nucleation whereas the silicates without fluorine did ...

A new and completely diastereoselective method for the introduction of fluorine into a noncarbohydrate sugar ring precursor has been developed. The use of N-fluorodibenzenesulfonimide (5) for the electrophilic fluorination of chiral lactone 4, which is derived from L-glutamic acid, yields the key intermediate 6. This is transformed into an anomeric acetate 8 and is used for the synthesis of a n...

Fluorine substituents in the phenyl ring of methyl fluorophenyl carbamates and fluorophenyl isocyanates were varied to determine the influence of fluorine substituents on fungal resistance of wood containing them. In southern pine impregnated with methyl fluorophenyl carbamates, increased fluorine substitution of the phenyl ring increased fungal resistance. Methyl pentafluorophenyl carbamate an...