Phenomena preceding precipitation of gold(i) sulfide in the reaction of aqueous tetrachloroauric acid with sodium sulfide have been studied applying several time-resolved in situ techniques. As can be deduced from UV-vis absorption spectroscopy, soluble species ("pre-nucleation clusters") emerge within several seconds and slightly change with time; the spectra, along with the previous data for ...

The Iron Mountain Mine Superfund Site near Redding, California, is a massive sulfide ore deposit that was mined for iron, silver, gold, copper, zinc, and pyrite intermittently for nearly 100 years. As a result, both water and air reached the sulfide deposits deep within the mountain, producing acid mine drainage consisting of sulfuric acid and heavy metals from the ore. Particularly, the draina...

Thiolate-protected gold nanoclusters are explored for catalytic application in the selective oxidation of sulfide to sulfoxide by PhIO. The TiO(2)-supported Au(25)(SR)(18) nanocluster catalysts give rise to high catalytic activity (e.g.∼97% conv. of Ph-S-CH(3) and ∼92% selectivity for Ph-S(=O)-CH(3) sulfoxide) and show excellent recyclability in the sulfoxidation process.

Abstract –– Tambang Sawah Area, Lebong Regency, Bengkulu Province, is geologically located in the Barisan mountains and Sumatra fault zone. The prospect of area lies physiography central Sumatran ranges composed by igneous rocks Sunda – Banda magmatic arc. This study aimed to understand deposit geology ore characteristics gold at area. Quartz vein mineralization occurred granite rock intruded i...

We report a one-pot, two-step strategy to synthesize fluorescent gold nanodots (AuNDs) co-modified with 1-(10-mercaptodecyl)-5-methylpyrimidine-2,4-dione (TSH) and 11-mercaptoundecanoic acid (MUA) through a ligand exchange reaction and demonstrate their capability of selective sulfide sensing in aqueous media on the basis of fluorescence recovery.

Cross-conjugated bifunctional species including a phosphine, phosphine oxide, phosphine sulfide, phosphonium salt, phosphorus ylide and a gold(I) phosphine complex have been prepared. The photophysical characteristics of the series of compounds have been determined experimentally and are discussed/compared with simpler analogues lacking cross-conjugated branches and rationalized on the basis of...

A new model has been developed both as a research tool and in collaboration with industry partners. In this paper, the successful application of the model to simulate rising main systems on the Gold Coast was demonstrated and tested in systems with oxygen injection intended for control of dissolved sulfide and odour.