An improved method for determination of Mo by thiocyanate has been standardized by employing thioglycollic acid, instead of currently employed stannous chloride, as reductant of Mo. The method ensures stability of the colored complex in aqueous acidic medium for about 3.5 hours which is otherwise unachievable and the color unstable while using stannous chloride. The method is linear over 0.5 to...

In this research, selective flotation of Mo from the Sungun Cu-Mo concentrate was evaluated in different operating conditions. It was found that the addition of 16 kg/t Na2S into flotation pulp and aeration decreased rapidly the initial oxidized- reduction potential (ORP) of the pulp from +228mV to -597 mV (with reference to standard Ag/AgCl electrode) and increasing the amount of Na2S by 50kg/...

Interaction of lanthanum isopropoxide with molybdenum(VI) alkoxides in La/Mo ratios varying from 3:1 to 1:1 in acetophenon or allyl alcohol as solvents offers nanosized poorly crystalline products of complex composition, where the precipitation of Mo-rich ones is followed by the formation of La-rich ones with conservation of the reaction stoichiometry in total. Thermal treatment of the precipit...

It is well known that it is undecidable in general whether a given programmeets its speci cation In contrast it can be checked easily by a machine whether a formal proof is correct and from a constructive proof one can automatically extract a corresponding program which by its very construction is correct as well This at least in principle opens a way to produce correct software e g for safety ...

Nitrogenase consists of two proteins: an iron containing protein and an iron and molybdenum (FeMo) containing protedl,21. Recent analyses[3] of MO EXAFS data of the FeMo protein and the FeMo COfactod41 isolated from it have led to the conclusion that the Mo atom is prinprily coordinated to sulfur and is separated by < 3 A from another metal atom, not Mo and,therefore, Fe, and that the Mo coordi...

North ern Van cou ver Is land is richly en dowed in a va ri ety of base and pre cious-metal de pos its. For ex am ple, the Cu-Mo-Au por phyry de posit at the for mer Is land Cop per mine (1971–1994) pro duced ap prox i mately 345 mil lion tonnes of ore with av er age head grades of 0.41 wt% Cu, 0.017% Mo, 0.19 g/t Au and 1.4 g/t Ag (Perello et al., 1995). Other por phyry de pos its are known to...

The unique dodecanuclear cluster compound Re12CS17 was prepared and studied by X-ray, complex impedance method and density functional theory (DFT). The compound is amorphous, possesses semiconducting properties. Computer simulations showed that the Re and S atoms at the external borders of the neighboring molecules Re12CS17 can form sufficiently strong Re···S intermolecular bonds, similar to th...

Introduction One of the best methods in the diagnosis and control of breast cancer is mammography. The importance of mammography is directly related to its value in the detection of breast cancer in the early stages, which leads to a more effective treatment. The purpose of this article was to calculate the X-ray spectrum in a mammography system with Monte Carlo codes, including MCNPX and MCNP5...

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The catalytic hydrogenation of lactic acid to 1,2-propanediol with supported Ru catalysts in water was investigated. The influence of catalyst support (activated carbon, γ-Al2O3, SiO2, TiO2, and CeO2) and promoters (Pd, Au, Mo, Re, Sn) on the catalytic performance was evaluated. Catalytic tests revealed that TiO2 yields the best Ru catalysts. With a monometallic Ru/TiO2 catalyst, a 1,2-propaned...