1. A lean-burn natural gas-fuelled diesel engine comprising an exhaust system comprising an oxidation catalyst.
2. An engine according to claim 1, wherein the exhaust system comprises an exhaust-driven turbocharger and wherein the oxidation catalyst is located between the engine and the turbocharger.
3. An engine according to claim 2, wherein the oxidation catalyst is located within an exhaust manifold.
4. An engine according to claim 3, wherein the engine has a plurality of cylinders and each cylinder has an oxidation catalyst within its exhaust manifold.
5. An engine according to claim 2, wherein the oxidation catalyst is located within the exhaust gas inlet of the turbocharger.
6. An engine according to claim 1, wherein the oxidation catalyst comprises at least one precious metal.
7. An engine according to claim 6, wherein the at least one precious metal is selected from the group consisting of platinum, palladium gold and combinations thereof.
8. An engine according to claim 7, wherein the oxidation catalyst comprises a combination of palladium and gold.
9. An engine according to claim 8, wherein at least some of the palladium and gold is present as an alloy.
10. A vehicle comprising an engine according to claim 1.
11. A stationary engine for power generation according to claim 1.
12. A method of improving methane emissions from a lean burn natural gas-fuelled diesel engine, comprising passing exhaust gas from the engine through an oxidation catalyst effective to oxidise methane at the exhaust gas temperature.
13. A method according to claim 12, comprising passing the exhaust gas treated by the oxidation catalyst into a turbocharger.
14. A vehicle according to claim 10, wherein the vehicle is a heavy-duty vehicle.
15. A system comprising:
a lean burn natural gas-fuelled diesel engine; and
an exhaust system,
wherein the exhaust system comprises an oxidation catalyst and a turbocharger, and the oxidation catalyst is positioned upstream of the turbocharger.
16. A system according to claim 15, wherein the exhaust system comprises a second oxidation catalyst positioned downstream of the turbocharger.
17. A system according to claim 15, wherein the exhaust system further comprises an additional component selected from the group consisting of a particulate filter, a NOx trap, a selective catalytic reduction conversion catalyst, an ammonia destruction catalyst, and combinations thereof.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A floatation apparatus, comprising:
a generally polygonal frame having an upper tube parallel to a lower tube, and two parallel side tubes;
a plurality of generally adjacent and parallel floatation cylinders located within the frame, generally perpendicular to the side tubes and parallel to the upper and lower tubes, each cylinder having a hollow center along a longitudinal axis;
an elongated tie connecting each of the floatation cylinders to the frame; and
an elongated rod located within the each of the side tubes,
wherein the side tubes comprise a plurality of holes aligned with an adjacent hollow center of an adjacent floatation cylinder, and
wherein the elongated tie is a rope connected end to end forming a continuous loop located within the hollow center of each floatation cylinder and through a corresponding hole on each of the side tubes, and further looped around the elongated rods within the side tubes.
2. The apparatus as claimed in claim 1 further comprising an additional floatation cylinder surrounding the upper tube.
3. The apparatus as claimed in claim 2 further comprising an additional floatation cylinder surrounding the lower tube.
4. The apparatus as claimed in claim 1 wherein the elongated tie is a band connected end to end forming a continuous loop that is disposed through the hollow center of each floatation cylinder and looped around each of the side tubes.
5. The apparatus as claimed in claim 1 further comprising an elbow located at each corner of the frame.
6. The apparatus as claimed in claim 1 wherein the hollow cylinders are closed cell polyethylene foam.
7. A recreational system, comprising:
a first floatation apparatus, including:
a generally polygonal frame having an upper tube parallel to a lower tube, and two parallel side tubes;
a plurality of generally adjacent and parallel floatation cylinders located within the frame, generally perpendicular to the side tubes and parallel to the upper and lower tubes, each cylinder having a hollow center along a longitudinal axis; and
an elongated tie connecting each of the floatation cylinders to the frame;
a second floatation apparatus connected to the first floatation apparatus, the second apparatus including:
a generally polygonal frame having an upper tube parallel to a lower tube, and two parallel side tubes;
a plurality of generally adjacent and parallel floatation cylinders located within the frame, generally perpendicular to the side tubes and parallel to the upper and lower tubes, each cylinder having a hollow center along a longitudinal axis; and
an elongated tie connecting each of the floatation cylinders to the frame; and
a planar adjustment plate connected to ends of each elongated tie,
wherein second ends of the frames are connected to one another by elongated ties,
wherein the elongated ties are adjustable to fix an angular orientation between the two apparatuses,
wherein the elongated ties adjust to a length such that the apparatuses are arranged in an angular orientation sufficient to allow a user to sit in a lounged position.
8. The system as claimed in claim 7 wherein the first and second apparatuses are hingably connected to one another at first ends of the frames by ties.
9. The system as claimed in claim 7 wherein the planar adjustment plate includes three holes, the elongated ties being knotted at one end and threaded through a first hole through an upper surface of the plate, through a second hole through a lower surface of the plate and through a third hole through the upper surface of the plate.
10. The system as claimed in claim 9 wherein the plate is triangular.
11. The system as claimed in claim 8 wherein the ties are nylon rope.
12. The system as claimed in claim 7 wherein the elongated ties are nylon rope.