We have determined fluorine abundances from the [F II] λ4789 and [F IV] λ4060 nebular emission lines for a sample of planetary nebulae (PNe). Our results show that fluorine is generally overabundant in PNe, thus providing new evidence for the synthesis of fluorine in asymptotic giant branch (AGB) stars. [F/O] is found to be positively correlated with the C/O abundance ratio, in agreement with t...

• Fluorine-free superhydrophobic and self-cleaning cotton fabric was fabricated. The modified tolerant towards different harsh conditions. prepared performed great oil–water separation MB photodegradation. efficiency above 99.8% with 6000 L·m ?2 ·h ?1 after 20 cycles. photodegradation 97% 5 Wastewater treatment is a process of significant socio-environmental implications, constantly calling for...

the use of recycled bassanite, produced from gypsum wastes, in ground improvement projects is initiated recently in japan to eliminate the huge quantities of gypsum wastes. meanwhile the use of recycled bassanite has a positive effect on the environment and economy, it has many challenges. these challenges are related to the release of fluorine more than the standard limits results in contamina...

Three hundred and five coal samples were taken from the main coal mines of twenty-six provinces, autonomous regions, and municipalities of China. The method of pyrohydrolysis was applied to measure the fluorine content in the samples, which exhibit logarithmic normal frequency distributions. The range of fluorine content in dry coal varies from 25 to 1230 mg/ kg with a geometric mean of 136 mg/...

Before the rationing of tea was introduced, New Zealand had the third largest annual consumption of tea in the world, namely 8.2 Ib./person. Subsequently, the ration of 2 oz./wcek with extra concessions to people working in factories and offices provided an annual consumption of 6-5 lb./person. Most foods are found to be poor sources of fluorine, even when grown in fluorinerich soils, supposedl...

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Oxynitride glasses are found as grain boundary phases in silicon nitride ceramics. They are effectively alumino-silicate glasses in which nitrogen substitutes for oxygen in the glass network, and this causes increases in glass transition and softening temperatures, viscosities (by two to three orders of magnitude), elastic moduli and microhardness. Calcium silicate-based glasses containing fluo...

Fluorine is the 13th most abundant element and, with other fluorine containing functional groups, is a most effective element in biological substances, pharmaceuticals, agrochemicals, liquid crystals, dyes, polymers and a wide range of consumer products. This reflects its resistance to metabolic change due to the strength of the C-F bond providing biological stability and the application of its...

1. INTRODUCTION Despite being largely absent from natural products and biological processes, fluorine plays a conspicuous and increasingly important role within pharmaceuticals and agro-chemicals, as well as in materials science. 1a−c Indeed, as many as 35% of agrochemicals and 20% of pharmaceuticals on the market contain fluorine. 1d Fluorine is the most electronegative element in the periodic...