Samples of the waste rock obtained from Marofengin South Africa ground 60, 70 and 80% passing 75µm were leached with cyanide in bottle roll tests. The results obtained showed that the percentage gold dissolution depends more on the ore size consists than on the cyanide concentration with the highest average dissolution rates of 88.75, 94.34 and 95.90% found at 600, 500 and 500 ppm, for 60, ...

Abstract The search for biosignatures on exoplanets connects the fields of biology and biochemistry to astronomical observation, with hope that we might detect evidence active biological processes worlds outside solar system. Here focus a complementary aspect exoplanet characterization connecting astronomy prebiotic chemistry: molecules associated origin life, prebiosignatures. Prebiosignature ...

an efficient, mild and environmentally friendly method was developed for the strecker reaction to synthesize α-aminonitriles in the presence of methyl imidazolium hydrogen sulfate ([hmim][hso4]) as an efficient catalyst. these syntheses were performed via a one-pot three-component condensation of aldehydes (or ketones), amines, and trimethylsilyl cyanide under mild and solvent free conditions.

We use a multifluid hydrodynamical-chemical model of cometary comae to predict the HNC and HCN abundances in comets Hyakutake and Hale-Bopp for a variety of initial parameters. We find, in general, that the presence of methanol in the nuclear ices inhibits the synthesis of HNC from HCN through proton transfer reactions in the coma. For Hale-Bopp, we find that because of the large gas production...

We present a search for HCN emission from four high redshift far infrared (IR) luminous galaxies. Current data and models suggest that these high z IR luminous galaxies represent a major starburst phase in the formation of spheroidal galaxies, although many of the sources also host luminous active galactic nuclei (AGN), such that a contribution to the dust heating by the AGN cannot be precluded...

Blood cyanide (HCN) or plasma thiocyanate (SCN) concentrations, or both, were measured in 30 patients (ages 11 months-72 yr) receiving sodium nitroprusside (SNP) for 12-314 h. Sequential measurements in three of these patients (infused 5, 12 and 13 days) showed that HCN concentrations varied with dose rate, while SCN concentrations increased linearly with increasing SNP dose. The accumulated da...

An ab initio study of the stability, spectroscopic properties, and isomeric equilibrium of the hydrogen-bonded HCN...H2O and H2O...HCN isomers is presented. Density functional theory and perturbative second-order MP2 and coupled-cluster CCSD(T) calculations were carried out and binding energies obtained with correlation-consistent basis sets including extrapolation to the infinity basis set lev...

A four-dimensional intermolecular potential-energy surface has been calculated for the HCN-HCl complex, with the use of the coupled cluster method with single and double excitations and noniterative inclusion of triples. Data for more than 13,000 geometries were represented by an angular expansion in terms of coupled spherical harmonics; the dependence of the expansion coefficients on the inter...

The aim of this study was to assess the effect rubber seed kernel heat processing on in vitro rumen biohydrogenation fatty acids and fermentation. experiment conducted with a completely randomized design (CRD). inclusion RSK at 0% (CON) 20% different methods as follows: Raw (RAWR), roasted (ROR), microwave irradiated (MIR), were heated hot air oven (RHO) total mixed ration (TMR) diets. hydrogen...

The release of hydrogen cyanide from Amelanchier alnifolia was monitored at 30 C and -10 C following lethal freezing at both slow and fast rates. Assuming that hydrogen cyanide release indicates membrane damage, it was concluded that during a fatal freeze-thaw cycle membrane damage occurred during cell contraction and, therefore, was not dependent upon membrane area expansion during thawing.