In this study, the oxygen reduction reaction (ORR) in Ca -containing dimethyl sulfoxide (DMSO) at well-ordered and rough electrode surfaces is compared by using cyclic voltammetry, differential electrochemical mass spectrometry, rotating ring disk electrode, and atomic force microscopy measurements. Slightly soluble CaO is the main product during early ORR on gold electrodes; after completion of a monolayer of CaO and/or CaO , which is formed in parallel and in competition to the peroxide, only superoxide is formed. When the monolayer is completely closed on smooth annealed Au, no further reduction occurs, whereas on rough Au a defect-rich layer allows for continuous formation of superoxide.
View Article and Find Full Text PDFA new method for simultaneously determining gas diffusivities and solubilities in liquids was presented and discussed in detail in Part I of this series. In this part of the series, the new measurement cell was employed to determine oxygen solubilities and diffusivities in 20 different dimethyl sulfoxide-based electrolytes. In addition, a comparison to values available in literature was made.
View Article and Find Full Text PDFThe structure of the precursor of a molt-inhibiting hormone (MIH) of the American crayfish, Orconectes limosus was determined by cloning of a cDNA based on RNA from the neurosecretory perikarya of the X-organ in the eyestalk ganglia. The open reading frame includes the complete precursor sequence, consisting of a signal peptide of 29, and the MIH sequence of 77 amino acids. In addition, the mature peptide was isolated by HPLC from the neurohemal sinus gland and analyzed by ESI-MS and MALDI-TOF-MS peptide mapping.
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