Effect of current change on iron-copper-nickel coating on nickel foam for hydrogen production

rthrospira sp. is an aquatic and photosynthetic microorganism that is extensively employed as a food supplement due to its rich contents of nutrients, proteins, and carbohydrates. In this study, a local strain of cyanobacterium of the genus Arthrospira was isolated from the Iraqi soil, in the region of Mosul city, using the Chu’s Medium No. 10. The growth rate, as well as the effects on biomass and cellular component contents of proteins, carbohydrates, and chlorophyll of this strain, were evaluated on the molasses medium alone or supplemented with iron, copper, nickel, cadmium and cobalt salts after fifteen days of incubation. The results showed that the best growth rate (1.09 OD), the highest value of biomass (120.0 mg/l), proteins content (297.2 mg/l), chlorophyll content (14.9 mg/l) and carbohydrates content (400.0 mg/l) of Arthrospira sp. was achieved after fifteen days of incubation. Generally, it was observed that adding iron, copper, nickel, cadmium, and cobalt salts into the molasses medium increased the contents of biomass, proteins, and carbohydrates of Arthrospira sp.. It was noticed that the highest biomass concentration (1960 mg/l) was obtained when Arthrospira sp. grown on molasses medium supplemented with nickel. Also, none of the metal salts added to the molasses medium increased the protein content of Arthrospira sp.. Conversely, adding copper, nickel, and cobalt to the medium showed an adverse effect on the protein content. It was shown that adding iron metal salts into the molasses medium increased the carbohydrates and the chlorophyll contents of Arthrospira sp.. These results suggest that Arthrospira sp. can be utilized for the bioremediation of heavy metals pollution in the environment and industrial sites.

Download Full-text

From Colonialism to Neoliberalism: Critical Reflections on Philippine Mining in the "Long Twentieth Century"

10.31235/osf.io/4g65e ◽

2018 ◽

Author(s):

Alvin Camba

Keyword(s):

Twentieth Century ◽

Capital Expenditure ◽

The Philippines ◽

The Other ◽

Archival Data ◽

Mining Companies ◽

Copper Nickel ◽

Operational Costs ◽

Iron Copper ◽

The One

Through an analysis of archival data and findings from interviews with industry leaders, I explore the genesis, rise, and fall of the various Philippine mineral regimes of the twentieth century. Specifically, I examine the background of successive and overlapping colonial and neocolonial powers in three eras: late colonial (1901-1941), national developmental (1945-1964), and state authoritarianism (1965-1985). I also briefly examine the current neoliberal mineral regime (1986-present). I argue that, to date, capitalist enterprises and neocolonial powers have pursued two contradictory paths to extract precious (gold and silver) and base (chromite, iron, copper, nickel, magnesium, and ore) metals in the Philippines. On the one hand, mining companies appropriated expansive land, underpriced labor and inexpensive food to subsidize capital expenditure and mineral operations. The appropriation of basic inputs - or what is referred to as "cheap natures" - allowed these companies to reduce their sunken investments and operational costs. But on the other hand, as the sector developed more, it became increasingly difficult to appropriate such "cheap natures." While initially profitable because of successful appropriation of "cheap natures," companies eventually experienced decreasing returns because of the problems this caused.

Download Full-text