down-hill gradient
61Wireless energy transfer — or wireless power is the transmission of electrical energy from a power source to an electrical load without artificial interconnecting conductors. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous,… …
62particle accelerator — accelerator (def. 7). [1945 50] * * * Device that accelerates a beam of fast moving, electrically charged atoms (ions) or subatomic particles. Accelerators are used to study the structure of atomic nuclei (see atom) and the nature of subatomic… …
63Lock (water transport) — Canal lock and lock keeper s cottage on the Aylesbury Arm of the Grand Union Canal at Marsworth in Hertfordshire, England …
64Northern Counties Committee — The Northern Counties Committee (NCC) was a railway that served the north east of Ireland. It was built to Irish gauge (1,600 mm (5 ft 3 in)) but later acquired a number of 914 mm (3 ft)  narrow gauge… …
65Telford Steam Railway — Heritage Railway name = Telford Steam Railway locale = Horsehay, Shropshire, England terminus = Spring Village linename = Severn Junction Railway originalgauge = RailGauge|ussg preservedgauge = RailGauge|ussg operator = Telford Horsehay Steam… …
66Displacement chromatography — is a chromatography technique in which a sample is placed onto the head of the column[n 1] and is then displaced by a solute that is more strongly sorbed than the components of the original mixture. The result is that the components are resolved… …
67Convection — This figure shows a calculation for thermal convection in the Earth s mantle. Colors closer to red are hot areas and colors closer to blue are cold areas. A hot, less dense lower boundary layer sends plumes of hot material upwards, and likewise,… …
68Heat transfer — is a discipline of thermal engineering that concerns the exchange of thermal energy from one physical system to another. Heat transfer is classified into various mechanisms, such as heat conduction, convection, thermal radiation, and phase change …
69Passing loop — Trains in a passing loop A passing loop (also called a passing siding, crossing loop, crossing place or, colloquially, a hole) is a place on a single line railway or tramway, often located at a station, where trains or trams in opposing… …
70Uranium mining — The Ranger Uranium Mine in Australia …
