effect of methanol concentration and channel depth of bipolar plates on the performance of single direct methanol fuel cell was investigated experimentally. the membrane used in this experiment was nafion117. dimension of the single cell were 10cm 10 cm. methanol concentrations of 0.50, 1.0, 1.5, 2.0, 3.0 molar were used. channel depth of the bipolar plates were chosen to be 1.0, 1.5, 2.0 mm, a...

UNLABELLED Many methylotrophic taxa harbor two distinct methanol dehydrogenase (MDH) systems for oxidizing methanol to formaldehyde: the well-studied calcium-dependent MxaFI type and the more recently discovered lanthanide-containing XoxF type. MxaFI has traditionally been accepted as the major functional MDH in bacteria that contain both enzymes. However, in this study, we present evidence tha...

Aquatic ecosystems are often contaminated by multiple substances. Nitrate, a common aquatic pollutant, strongly influenced the cycling of arsenic (As) under anoxic conditions in urban Upper Mystic Lake (Massachusetts, USA) by oxidizing ferrous iron [Fe(II)] to produce As-sorbing particulate hydrous ferric oxides and causing the more oxidized As(V), which is more particle-reactive than As(III) u...

The rate of release of iron to 1,10-phenanthroline from ferritin fractions of different iron contents has been studied. The experimental results could be interpreted by a simple hypothetical model of the shape of the hydrous ferric oxide micelle at different iron contents, and reasonable correlation obtained between the rate of release and the calculated micelle surface areas. Initial rates of ...

Multiplexed thermal desorption spectroscopy was used to study the influence of preadsorbed and postadsorbed deuterium on a methanol monolayer on Pd(111). In particular, the effect of atomic deuterium exposure on the reaction products was examined in detail. Preadsorbed deuterium hinders the formation of chemisorbed methanol and favors physisorption of methanol. This leads to a strong reduction ...

Methanol is a versatile chemical feedstock, fuel source, and energy storage material. Many reactions involving methanol are catalyzed by transition metal surfaces, on which hydrogen-bonded methanol overlayers form. As with water, the structure of these overlayers is expected to depend on a delicate balance of hydrogen bonding and adsorbate-substrate bonding. In contrast to water, however, relat...

Volcán San Pedro in the Andean Southern Volcanic Zone (SVZ) Consequently, the role of young, unradiogenic hydrous gabbro in Chile, comprises Holocene basaltic to dacitic lavas with trace generating dacite and contaminating basalt may be underappreciated element and strontium isotope ratios more variable than those of in the SVZ. most Pleistocene lavas of the underlying Tatara–San Pedro complex....