Cyanidation is the main process for gold and silver recovery from its ores. In this study, a process is proposed to recover copper and cyanide from barren solutions from the Merrill-Crowe cementation process with zinc dust. This technology is based on inducing nucleated precipitation of copper and silver in a serpentine reactor, using sodium sulfide as the precipitator, and sulfuric acid for pH...

BACKGROUND Cigarette smoking is a well recognized cause of diseases such as lung cancer, chronic obstructive pulmonary disease and cardiovascular disease. Of the more than 5000 identified species in cigarette smoke, at least 150 have toxicological activity. For example, formaldehyde and acetaldehyde have been assigned as Group 1 and Group 2B carcinogens by IARC, and hydrogen cyanide has been id...

The chemistry of hydrogen cyanide (HCN) is believed to be central to the origin of life question. Contradictions between Cassini-Huygens mission measurements of the atmosphere and the surface of Saturn's moon Titan suggest that HCN-based polymers may have formed on the surface from products of atmospheric chemistry. This makes Titan a valuable "natural laboratory" for exploring potential nonter...

There is increasing evidence that environmental change associated with urbanization can drive rapid adaptation. However, most studies of urban adaptation have focused on coarse vs. rural comparisons or sampled along a single urban–rural gradient, thereby ignoring the role within-city heterogeneity might play in to environments. In this study, we examined fine-scale variation presence hydrogen c...

More than half a century ago, Irish physicist John Desmond Bernal and Swiss geochemist Victor M. Goldschmidt independently proposed that clay minerals may have played an important role in prebiotic synthesis (Bernal 1949; Goldschmidt 1952). I concur that mineral catalysis must have had a central role in prebiotic synthesis because most uncatalyzed reactions start from simple precursors like hyd...

Emission of nitrogen oxides (NOx) and soot particles during the combustion biomass fuels municipal solid waste is a major environmental issue. Hydrogen cyanide (HCN) acetylene (C2H2) are important precursors NOx particles, respectively. In current work, infrared tunable diode laser absorption spectroscopy (IR-TDLAS), as non-intrusive in situ technique, was applied to quantitatively measure HCN ...

The origin of life on Earth involves the early appearance an information-containing molecule such as RNA. basic building blocks RNA could have been delivered by carbon-rich meteorites, or produced in situ processes beginning with synthesis hydrogen cyanide (HCN) Earth's atmosphere. Here, we construct a robust physical and non-equilibrium chemical model atmosphere is supplied from impact degassi...

[1] We report the first in situ measurements of hydrogen cyanide (HCN) and methyl cyanide (CH3CN, acetonitrile) from the Pacific troposphere (0–12 km) obtained during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) airborne mission (February–April 2001). Mean HCN and CH3CN mixing ratios of 243 ± 118 (median 218) ppt and 149 ± 56 (median 138) ppt, respectively, were measured...

Alliaria petiolata (garlic mustard, Brassicaceae) contains the glucosinolate sinigrin as well as alliarinoside, a γ-hydroxynitrile glucoside structurally related to cyanogenic glucosides. Sinigrin may defend this plant against a broad range of enemies, while alliarinoside confers resistance to specialized (glucosinolate-adapted) herbivores. Hydroxynitrile glucosides and glucosinolates are two c...

Pseudomonas fluorescens CHA0 produces hydrogen cyanide (HCN), a secondary metabolite that substantially contributes to this strain's biocontrol ability. Cyanogenesis is induced by oxygen-limiting conditions, but abolished by iron depletion. In P. fluorescens, the anaerobic regulator ANR and the global activator GacA are both required for the maximal expression of the HCN biosynthetic genes hcnA...