摘要:
Systems, methods, and devices for inelastic gamma-ray logging are provided. In one embodiment, such a method includes emitting neutrons into a subterranean formation from a downhole tool to produce inelastic gamma-rays, detecting a portion of the inelastic gamma-rays that scatter back to the downhole tool to obtain an inelastic gamma-ray signal, and determining a property of the subterranean formation based at least in part on the inelastic gamma-ray signal. The inelastic gamma-ray signal may be substantially free of epithermal and thermal neutron capture background.
摘要:
Systems, methods, and devices for inelastic gamma-ray logging are provided. In one embodiment, such a method includes emitting neutrons into a subterranean formation from a downhole tool to produce inelastic gamma-rays, detecting a portion of the inelastic gamma-rays that scatter back to the downhole tool to obtain an inelastic gamma-ray signal, and determining a property of the subterranean formation based at least in part on the inelastic gamma-ray signal. The inelastic gamma-ray signal may be substantially free of epithermal and thermal neutron capture background.
摘要:
A tool having a neutron source, a gamma ray detector, and a photomultiplier tube is provided. The gamma ray detector and the photomultiplier tube are at least partially surrounded by a layer of boron. The tool is used to make measurements, and the number of prompt gamma rays emitted by the boron is determined from the measurements. The number of neutrons detected may be inferred using the determined number of prompt gamma rays. The tool may also have a layer of neutron absorbing material different from boron or a layer of heavy metal at least partially surrounding the boron. The tool may be a logging tool used to delineate a porous formation and to determine its porosity. The tool may have a plurality of gamma ray detector/photomultiplier tube pairs and those pairs may be used to determine a formation hydrogen index and/or a borehole hydrogen index.
摘要:
A tool having a neutron source, a gamma ray detector, and a photomultiplier tube is provided. The gamma ray detector and the photomultiplier tube are at least partially surrounded by a layer of boron. The tool is used to make measurements, and the number of prompt gamma rays emitted by the boron is determined from the measurements. The number of neutrons detected may be inferred using the determined number of prompt gamma rays. The tool may also have a layer of neutron absorbing material different from boron or a layer of heavy metal at least partially surrounding the boron. The tool may be a logging tool used to delineate a porous formation and to determine its porosity. The tool may have a plurality of gamma ray detector/photomultiplier tube pairs and those pairs may be used to determine a formation hydrogen index and/or a borehole hydrogen index.
摘要:
A method is provided to detect neutrons using a boron-shielded gamma-ray detector, which will detect the 0.48-MeV prompt gamma ray due to the 10B (n,α)7Li reaction. The gamma ray detector can be a proportional gas counter, a scintillation based detector, or a semiconductor detector. Monoenergetic prompt gammas will produce a sharp peak in the pulse height spectrum of a gamma-ray spectroscopy detector. By surrounding a gamma detector with a layer containing 10B, we can measure the gamma signal and neutron signal at the same time and at the same physical location in an instrument. The approach can be used to measure neutron porosity simultaneous with gamma-ray counting or spectroscopy at the same location as long as the 0.48-keV gamma-ray from the neutron reaction does not interfere with the gamma-ray measurement.
摘要:
A fluid pump assembly is disclosed for performing in a damp environment. A pump member is provided that drives a quantity of fluid. A pump housing encloses the pump member and includes a breather hole for circulating cooling air around the pump member during operation. A cover is provided that substantially covers the breather hole and defines a tortuous path that enables air to circulate through the breather hole while preventing entry of water thereto.
摘要:
The invention concerns a communication system via ACARS messages intended to be placed onboard an aircraft, said system comprising a router (310, 310′) adapted to route said messages from and to a plurality of VHF, HF, SATCOM sub-networks. The system comprises a switch (360, 365) and an AoIP conversion gateway (380), the switch being connected to an HF or SATCOM transceiver module (340, 350) by means of a first two-way link (341, 351), and to said AoIP gateway by means of a second two-way link (381), the switch being adapted to select said first two-way link when it lies in a first switch position and the second two-way link when it lies in a second switch position, the switch lying in the second switch position if the aircraft is on the ground or less than a predetermined distance from the ground, otherwise it lies in the first position.
摘要:
A vehicle or equipment having a frame, a plurality of wheels, and an engine coupled to the frame. The engine includes a shaft. The vehicle or machine further comprising a first driving member coaxially coupled with the shaft, a first driven member driven in response to the first driving member, a transmission interconnecting the first driven member and at least one of the wheels, a second driving member coaxially coupled with the shaft, a second driven member driven in response to the second driving member, auxiliary equipment operable in response to the second driven member, and an alternator. The alternator includes a stator comprising a core and conductors disposed on the core, and a rotor coaxially coupled with the shaft. The rotor is operable to interact with the stator to produce electrical energy in the conductors.
摘要:
A chemical agent detector with a a lesser demand sensor, a greater demand sensor, an inlet; and a manifold; and methods associated therewith. The manifold is positioned between the inlet and the sensors, and includes a first intake associated with the lesser demand sensor, a second intake associated with a greater demand sensor, and at least one restrictor. The first intake is placed closer to the inlet than the second intake, and the second intake is isolated from the inlet by at least one restrictor within the manifold. The intakes and restrictor are sized and positioned such that the ratio between: the conductance of the path from the inlet to the greater demand sensor to the conductance of the path between the sensors effectively isolates the lesser demand sensor from the effects of the greater demand sensor.
摘要:
A drive system for a marine vessel. The drive system includes a drive shaft that is rotatable about a drive axis and a motor interconnected with the drive shaft and including a rotor that defines a motor axis that is substantially coaxial with the drive axis. The motor is operable at a motor speed to rotate the drive shaft. An engine has an output shaft interconnected with the drive shaft and is operable at an engine speed to rotate the drive shaft. The output shaft defines an engine axis that is substantially coaxial with the motor axis. A clutch is operable to inhibit the transfer of torque from the motor to the engine when the engine speed is less than a predetermined engine speed without disconnecting the output shaft from the drive shaft. A tiller arm includes a speed control. The speed control is operable to control the engine speed and to control the motor speed.