Abstract: The present invention concerns a copper electrowinning process suitable for the production of enhanced-quality cathodes from highly contaminated electrolytes. The process is performed in electrowinning cells including a plurality of anodes and cathodes, equipped with gas sparging elements at their bottom. It comprises the step of sparging gas across the cathodes, and is characterized in that the solution contains more than 100 mg/L of arsenic. The invention provides an alternative solution to the problem of cathode quality when dealing with highly contaminated electrolytes, in particular when containing high concentrations of arsenic.

Abstract: Agents and methods for qualitative and quantitative analysis a protein complex or protein complexes using isotope-labeled symmetrical bifunctional crosslinkers and mass spectrometry are provided. Targeting moieties, cell permeability moieties, or affinity moieties, may be appended to the bifunctional crosslinkers. The isotope-labeled symmetrical bifunctional crosslinkers may be used in a kit or as a library.

Abstract: Agents and methods for qualitative and quantitative analysis a protein complex or protein complexes using isotope-labeled symmetrical bifunctional crosslinkers and mass spectrometry are provided. Targeting moieties, cell permeability moieties, or affinity moieties, may be appended to the bifunctional crosslinkers. The isotope-labeled symmetrical bifunctional crosslinkers may be used in a kit or as a library.

Abstract: A safe analytical technique for determining the concentration amount of dibutyl and monobutyl phosphate degradation products in the TBP-dodecane solvent used in solvent extraction processes. This method of chemical analysis eliminates the use of diazomethane, which is toxic and explosive, thereby providing a safer laboratory technique for routine analyses required to monitor production solvent extraction processes. The solvent sample to be analyzed is spiked with mass labelled, deuterated dibutyl and monobutyl phosphates, which act as internal standards. After adding a silylating agent, bistrimethylsilyltrifluoracetamide, the sample is injected into a gas chromatograph/mass spectrometer, which measures the ratio between the labelled internal standard and the naturally occurring material to obtain a quantitative result.

Abstract: An improved internal standard for use in determining the concentration of decomposition products of tributyl phosphate in solvent used for solvent extraction. The improved internal standard includes deuterated variants of the decomposition products to be measured, e.g., deuterated dibutyl and monobutyl phosphoric acids. The use of deuterated dibutyl and monobutyl phosphoric acids eliminates the use of diazomethane, which is toxic and explosive, thereby providing a safer laboratory technique for routine analyses required to monitor production solvent extraction processes.

Abstract: An apparatus and a method providing an open-split interface between a gas chromatograph and a mass spectrometer for delivering a substantially solvent free sample material from the gas chromatograph to the mass spectrometer. The apparatus has a junction having an inlet to receive a gas chromatograph effluent. An inert auxiliary fluid such as helium supplied through a port is used to scavenge the solvent rich effluent to atmosphere. A transfer member disposed partially within the junction is initially positioned at a first position to accomplish the aforementioned scavenging action. The transfer member is then repositioned to a second position to direct the substantially solvent free sample to the mass spectrometer for a qualitative and a quantitative analysis.