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Study shows biodiesel blends in buses reduce PM, other harmful exhaust elements, EC and CO

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Before they can be used, however, it is essential to understand their physical properties, combustion chemistry, and characterization of the exhaust due to a number of issues associated with fuel properties—for example, a lower heating value and higher cloud point than regular diesel.

Exhaust 312
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New power-dense 2.0L GDI turbo with twin-scroll turbocharger and new combustion system offered in 2013 Chevrolet Malibu

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Rotocast aluminum cylinder head with sodium-filled exhaust valves. Rotocast aluminum cylinder head with sodium-filled exhaust valves. The exhaust valves have sodium-filled stems that promote valve cooling. At normal engine operating temperatures, the sodium inside the valve stem becomes liquid.

2013 236
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Researchers devise method to suppress thermal conductivity to improve thermoelectric materials for waste heat recovery

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A new study published in the journal Nature Materials has found a way to suppress the thermal conductivity in sodium cobaltate so that it can be used to harvest waste energy, with potential applications such as automotive waste heat recovery. Goff (2013) Suppression of thermal conductivity by rattling modes in thermoelectric sodium cobaltate.

Waste 186
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Haldor Topsøe ECO-Jet wins award; reducing soot, HC and heavy metal emissions from ships powered by bunker fuel

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Particulate filter systems are developed for diesel engine exhaust with a relatively low sulfur and ash content. The ECO-Jet process also removes other harmful substances from the exhaust of engines using bunker fuel, for instance poisonous hydrocarbons and metals including vanadium, iron, nickel, silicon and sodium.

Emissions 186
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MAN Diesel & Turbo delivers 1st IMO-certified two-stroke with Tier III NOx control, EGR systems

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two-stroke main-engines that feature integrated Exhaust Gas Recirculation (EGR) systems. EGR is a NO x emissions-control technology that works by recirculating a portion of an engine’s exhaust gas back to the engine cylinders. Sodium hydroxide dosing is therefore required to neutralise the acidic scrubber water.

Diesel 150
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Buick’s Ecotec 2.0L Turbo makes Wards Best Engines list; 2.0L turbo coming for Malibu

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The exhaust valves have sodium-filled stems that promote valve cooling. The A356 aluminum cylinder head is cast using a rotocast process for high strength, reduced machining and improved port flow. An advanced, electronically controlled turbocharger uses a twin-scroll design to increase power.

Engine 210
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New Federal-Mogul Powertrain high thermal conductivity seats and guides keep engine valves cooler; improved combustion, lower emissions

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For exhaust valve head alloys, every 20°C reduction in temperature negates the need for an upgrade to the next, more expensive alloy specification. The improvement in exhaust valve head temperatures was even more marked; on a solid valve the peak was reduced by up to 70°C and on a hollow, sodium-filled valve, by up to 67°C.

Engine 150