Solar panel parallel mounting configuration

A spacecraft includes a plurality of solar panels interconnected with a power coupler and an electrically operated device to provide power to the device when the solar cells are insolated. The solar panels are subject to bending distortion when entering or leaving eclipse. Spacecraft attitude disturbances are reduced by mounting each of the solar panels to an elongated boom made from a material with a low coefficient of thermal expansion, so that the bending of one panel is not communicated to the next. The boom may be insulated to reduce its bending during changes in insolation. A particularly advantageous embodiment mounts each panel to the boom with a single mounting, which may be a hinge. The single mounting prevents transfer of bending moments from the panel to the boom

Pipe inspection and repair system

A multi-module pipe inspection and repair device. The device includes a base module, a camera module, a sensor module, an MFL module, a brush module, a patch set/test module, and a marker module. Each of the modules may be interconnected to construct one of an inspection device, a preparation device, a marking device, and a repair device

Molecular and supramolecular chemistry of mono- and di-selenium analogues of metal dithiocarbamates

This bibliographic review summarises the coordination chemistry of mono- and diselenium analogues of metal dithiocarbamate ligands, [RRꞌNCS2]-, as revealed by X-ray crystallography and spectroscopy (77Se NMR and infrared). The Se-ligands are usually chelating but, bridging modes, up to 4, are known. Reflecting the larger size, greater polarisability and presence of a polar-cap (-hole), selenium atoms are more likely to be involved in secondary-bonding (chalcogen-bonding) than sulphur when a competition exists. Isostructural relationships are established across the series in about one-third of the structures

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US gas companies spend over $300 million annually detecting and repairing gas leaks in urban and suburban settings. The current approach is one of above-ground leak detection and pinpointing, followed by excavation, repair and restoration. The major cost incurred is typically that of digging and restoring the excavation site. The Gas Research Institute and the National Aeronautics and Space Administration are funding a program at Carnegie Mellon Universit

Explorer: Untethered Real-time Gas Main Assessment Robot System

Federal government agencies and an industrial industry consortium have funded Carnegie Mellon University (CMU) for the development of Explorer, a long range, untethered, modular inspection robot for the visual inspection of 6 ” and 8 ” natural gas distribution system pipelines. The robot can be launched into the pipeline under live conditions utilizing a commercial no-blow system via a specially designed attachment, and can negotiate diameter changes, 45-deg and 90-deg bends and tees, as well as inclined and vertical pieces of the piping network. The modular design of the system allows it to be expanded in the near future to include additional inspection and/or repair tools. The range of the robot is an order of magnitude higher than present state-of-the-ar