A system for transporting one or more items is provided. The system includes: a transportation tube disposed at least partially underground or at least partially above ground; a transportation pod to secure items therein for transport; a transportation actuator to propel the transportation pod through the transportation tube, the transportation actuator including a track extending through the transportation tube and a cable disposed at least partially inside the track, the cable configured to be coupled to the transportation pod as the transportation pod is propelled along the track; a first access point located proximate a first end of the transportation tube; and a second access point located proximate a second end of the transportation tube. Each of the first and second access points includes an opening configured to allow the transportation pod to be received into or removed from the transportation tube.

A microfabricated sheath flow structure for producing a sheath flow includes a primary sheath flow channel for conveying a sheath fluid, a sample inlet for injecting a sample into the sheath fluid in the primary sheath flow channel, a primary focusing region for focusing the sample within the sheath fluid and a secondary focusing region for providing additional focusing of the sample within the sheath fluid. The secondary focusing region may be formed by a flow channel intersecting the primary sheath flow channel to inject additional sheath fluid into the primary sheath flow channel from a selected direction. A sheath flow system may comprise a plurality of sheath flow structures operating in parallel on a microfluidic chip.

A microfabricated sheath flow structure for producing a sheath flow includes a primary sheath flow channel for conveying a sheath fluid, a sample inlet for injecting a sample into the sheath fluid in the primary sheath flow channel, a primary focusing region for focusing the sample within the sheath fluid and a secondary focusing region for providing additional focusing of the sample within the sheath fluid. The secondary focusing region may be formed by a flow channel intersecting the primary sheath flow channel to inject additional sheath fluid into the primary sheath flow channel from a selected direction. A sheath flow system may comprise a plurality of sheath flow structures operating in parallel on a microfluidic chip.

A method is described for maintaining a gaseous composition within a tube (that is part of tubular transportation system for transporting passengers or cargos via a capsule), where the tube is arranged along a predetermined route. The method comprises: (a) pumping the tube to a pressure that is below atmospheric pressure until the tube is substantially evacuated; (b) identifying a predetermined power value; (c) identifying a first percentage, x, of hydrogen based on the predetermined power value identified in (b) and a leak rate associated with the tube; (d) maintaining within each tube in the plurality of substantially evacuated tubes, a gaseous composition comprising a mixture of a first percentage, x, of hydrogen and a second percentage, (100-x), of air.

A microfabricated sheath flow structure for producing a sheath flow includes a primary sheath flow channel for conveying a sheath fluid, a sample inlet for injecting a sample into the sheath fluid in the primary sheath flow channel, a primary focusing region for focusing the sample within the sheath fluid and a secondary focusing region for providing additional focusing of the sample within the sheath fluid. The secondary focusing region may be formed by a flow channel intersecting the primary sheath flow channel to inject additional sheath fluid into the primary sheath flow channel from a selected direction. A sheath flow system may comprise a plurality of sheath flow structures operating in parallel on a microfluidic chip.

A microfabricated sheath flow structure for producing a sheath flow includes a primary sheath flow channel for conveying a sheath fluid, a sample inlet for injecting a sample into the sheath fluid in the primary sheath flow channel, a primary focusing region for focusing the sample within the sheath fluid and a secondary focusing region for providing additional focusing of the sample within the sheath fluid. The secondary focusing region may be formed by a flow channel intersecting the primary sheath flow channel to inject additional sheath fluid into the primary sheath flow channel from a selected direction. A sheath flow system may comprise a plurality of sheath flow structures operating in parallel on a microfluidic chip.

Disclosed is a combined pumping/gas source unit configured for use in a tubular transportation system for transporting one or more passengers or one or more cargos via a capsule along a predetermined route, where the tubular transportation system comprises a plurality of substantially evacuated tubes arranged along the predetermined route, each tube in the plurality of substantially evacuated tubes maintained at a pressure that is below atmospheric pressure.

Disclosed within is an injection system for injecting and maintaining a gaseous composition (helium and air) within a tube (e.g., a tubular transportation system for transporting one or more passengers or one or more cargos via a capsule), where the tube is pumped to a pressure that is below atmospheric pressure until the tube is substantially evacuated and where the capsule has an outside skin layer having injection nozzles. A source of helium gas located on board the capsule releases the helium outside of the capsule via the nozzles to relieve pressure buildup in a stagnation point at the front of the capsule or to reduce effects of a choking flow around the capsule or to relieve the effects of a shockwave at the rear of the capsule.

A system for transporting one or more items is provided. The system includes: a transportation tube disposed at least partially underground or at least partially above ground; a transportation pod to secure items therein for transport; a transportation actuator to propel the transportation pod through the transportation tube, the transportation actuator including at least one cable configured to interface with the transportation pod, the at least one cable being driven by a motor to move the cable and the transportation pod through the transportation tube; a first access point located proximate a first end of the transportation tube; and a second access point located proximate a second end of the transportation tube. Each of the first and second access points includes an opening configured to allow the transportation pod to be received into or removed from the transportation tube.

A system for transporting one or more items is provided. The system includes: a transportation tube disposed at least partially underground or at least partially above ground; a transportation pod to secure items therein for transport; a transportation actuator to propel the transportation pod through the transportation tube, the transportation actuator including at least one cable configured to interface with the transportation pod, the at least one cable being driven by a motor to move the cable and the transportation pod through the transportation tube; a first access point located proximate a first end of the transportation tube; and a second access point located proximate a second end of the transportation tube. Each of the first and second access points includes an opening configured to allow the transportation pod to be received into or removed from the transportation tube.