Diamond-reinforced zinc sulphide composites have increased toughness as compared to that of pure zinc sulphide. While the mechanical properties of the composites are relatively insensitive to green state processing, the optical properties are greatly affected by the processing which governs the quality of diamond dispersion. Improved dispersion and hence good optical transmission have been achi...

A study was carried out to assess possible effects of low concentrations of hydrogen sulphide on respiratory function. The cohort comprised 26 male pulp mill workers (mean age 40.3, range 22-60 years) with a daily exposure to hydrogen sulphide in the workplace, and 10 volunteers, who had asthma (three men, mean age 40.7, range 33 to 50 years, and seven women, mean age 44.1, range 31 to 61 years...

The aim of the present study was to evaluate the impact of a multiple dose regimen of a liposomal formulation of meglumine antimoniate (LMA) on the pharmacokinetics of antimony in the bone marrow of dogs with visceral leishmaniasis and on the ability of LMA to eliminate parasites from this tissue. Dogs naturally infected with Leishmania chagasi received 4 intravenous doses of either LMA (6.5 mg...

The growing resistance of leishmaniasis to first-line drugs like antimonials in some regions limits the control of this parasitic disease. The precise mechanisms involved in Leishmania antimony resistance are still subject to debate. The reduction of intracellular SbIII accumulation is a common change observed in both laboratory-selected and field isolated resistant Leishmania strains, but the ...

Arsenic (As) levels in drinking water and in irrigation water used for rice paddies can exceed the World Health Organisation (WHO) drinking water quality limit of 0.05 mg L across many regions in South East Asia. This is due to the dissolution of As-rich minerals in the groundwater hosting bedrock. In polluted groundwater, concentrations can exceed water quality limits to a factor of 900, reach...

The present paper proposes an analytical procedure for speciation analysis of inorganic antimony in airborne particulate matter using slurry sampling and hydride generation atomic absorption spectrometry (HG QT AAS). During the antimony determination, a quartz T tube cell was heated to approximately 900 C using air–acetylene flame. The optimization step was performed by employing full two-level...

A kinetic model for flame inhibition by antimony-halogen compounds in hydrocarbon flames is developed. Thermodynamic data for the relevant species are assembled from the literature, and calculations are performed for a large set of additional species of Sb-Br-C-H-O system. The main Sb- and Br-containing species in the combustion products and reaction zone are determined using flame equilibrium ...

Sulphide was determined spectrophotometrically at 628 nm and pH 6.7 based on its catalytic reduction of toluidine blue in the presence of Se(IV) using a flow injection system. After optimization of the measuring conditions the calibration curve was found linear up to 25 mg/mL and the detection limit was 0.3 mg/mL (30 mL injections). The ...

Arsenic is the 20th most abundant element in the earth's crust at a level of about 2 ppm. It is a constituent of over 300 minerals and is commonly found in non-ferrous ores such as copper, lead, zinc, gold and uranium. Efficient separation of arsenic minerals from other sulphide minerals is of great importance for the metallurgical performance of flotation processes. This work was undertaken to...