The trend in strong weld metals is towards microstructures dominated by low carbon martensite. The role of oxide particles introduced into the metal during welding then becomes uncertain. The particles do not seem to affect the nucleation or growth of martensite. This is probably because this phase forms at relatively large driving forces and therefore does not rely on heterogeneous nucleation ...

Diesel exhaust (DE) has been implicated as a potential lung carcinogen. However, the exact components of DE that might be involved have not been clearly identified. In the past, nitrogen oxides (NO(x)) and carbon oxides (CO(x)) were measured most frequently to estimate DE, but since the 1990s, the most commonly accepted surrogate for DE has been elemental carbon (EC). We developed quantitative ...

The electrolytic decomposition of metal oxides to metal and oxygen is an extractive metallurgy principle that, when coupled with carbon-free electricity, drastically mitigates the global warming impact of metal production. The present perspective discusses the electrochemical engineering features of an unconventional electrolyte, molten oxides. A survey of its thermodynamic properties suggests ...

Recent U.S. Environmental Protection Agency emissions regulations have resulted in lower emissions of particulate matter and oxides of nitrogen from heavy-duty diesel trucks. To accelerate fleet turnover the State of California in 2008 along with the Ports of Los Angeles and Long Beach (San Pedro Bay Ports) in 2006 passed regulations establishing timelines forcing the retirement of older diese...

Two laboratory-scale sequencing batch reactors were used to study biological treatment of carbon and nitrogen in a new combined anaerobic-aerobic system. Piggery wastewater was used as a model effluent. The anaerobic reactor, fed with raw wastewater and nitrite/nitrate recycling from the aerobic reactor, carried out denitrification and anaerobic digestion of organic carbon. In the aerobic react...

The applications of electrospun carbon fiber webs to the development of energy storages devices, including both supercapacitors and lithium ion batteries (LIB), are reviewed. Following a brief discussion of the fabrication process and characterization methods for ultrafine electrospun carbon fibers, recent advances in their performance as supercapacitors and LIBs anode materials are summarized....

In this study the performance and emissions characteristics of a heavy-duty, direct injection, Compression ignition (CI) engine which is specialized in agriculture, have been investigated experimentally. For this aim, the influence of injection timing, load, engine speed on power, brake specific fuel consumption (BSFC), peak pressure (PP), nitrogen oxides (NOx), carbon dioxide (CO2), Carbon mon...

Biogenic Mn oxides were produced by the bacterium Leptothrix discophora SS-1 (= ATCC 3182) in a chemically defined mineral salts medium, and the Pb binding and specific surface area of these oxides were characterized. Growth of SS-1 in the defined medium with pyruvate as a carbon and energy source required the addition of vitamin B12. Complete oxidation of Mn(II) within 60 h required the additi...

Surfaces of carbon steel (CS) exposed to mixed cultures of iron-oxidizing bacteria (FeOB) and dissimilatory iron-reducing bacteria (FeRB) in seawater media under aerobic conditions were rougher than surfaces of CS exposed to pure cultures of either type of microorganism. The roughened surface, demonstrated by profilometry, is an indication of loss of metal from the surface. In the presence of C...