Abstract: A method of analyzing properties of a porous sample, typically a cylinder of porous rock, comprises centrifuging the sample while it contains at least one liquid, determining the distribution of at least one liquid in the sample by magnetic resonance imaging of the sample, and also determining the distribution of at least one magnetic resonance parameter, where the parameter is one of longitudinal relaxation time T1, transverse relaxation time T2 and diffusion coefficient D. Pore throat sizes can be determined from the distribution of at least one liquid in the sample and pore body sizes can be determined from the distribution of the magnetic resonance parameter enabling determination of a relationship between pore throat sizes and pore body sizes in the sample. This can be a relationship between individual values of pore throat size and an average of body sizes of pores having that individual pore throat size.

Abstract: Properties of a porous solid sample 19, which may be a core of rock taken from below ground are carried out using apparatus which performs both nuclear magnetic resonance (NMR) and porosimetry measurements. The apparatus has a magnet 11,12 providing a magnetic field and a radio frequency coil 20 for transmitting and/or receiving electromagnetic radiation so as to bring about NMR in the magnetic field, a pressure vessel 14, 15 to hold a sample 19 within the magnetic field, a supply of a non-wetting liquid connected to the vessel, means to apply pressure to the non-wetting liquid to force liquid into pores of the sample 19 means to measure applied pressure of the non-wetting liquid and means to measure volume thereof taken up by the sample. The pressure of non-wetting liquid may be increased in steps, using intruded liquid volume at each step to give a measurement of pore throat size using NMR at each step to give a measure of pore size such as diameter of equivalent sphere.

Abstract: An apparatus and method for NMR analysis of a plurality of core samples includes a core holder (11) that holds a core sample under pressurized conditions. A radio frequency coil (51) disposed about the core holder (11) generates a pulsed-mode magnetic field component over a sample volume occupied by the core sample. A support structure is removably secured to the respective core holder. A permanent magnet (65A, 65B) has an open configuration such that it is removably disposed into a position within the support structure about the radio frequency coil and the core holder. The open configuration allows the same permanent magnet to be used for NMR analysis of a plurality of core samples without the need for depressurizing the respective core holder and disassembling the core holder and corresponding load frame for each core sample. It also allows multiple core samples to be prepared for NMR analysis while separated from the NMR measurement apparatus.

Abstract: A laboratory NMR methodology (and corresponding laboratory apparatus) defines a sample volume. The method stores downhole tool data corresponding to a hydrocarbon-bearing sample collected from a given subsurface formation. The downhole tool data includes parameters pertaining to magnetic fields used by a downhole tool during a suite of NMR measurements of the given subsurface formation. The sample is positioned in the sample volume of the laboratory apparatus, which applies a static magnetic field in the sample volume. Furthermore, the laboratory apparatus applies a suite of NMR measurements to the sample volume to thereby determine a property of the sample. The NMR measurements of the suite each include a pulse sequence of oscillating magnetic field in conjunction with a pulsed-mode gradient field. The pulsed-mode gradient field is based on the stored downhole tool data corresponding to the sample. A laboratory NMR methodology for optimizing downhole NMR measurements is also described.

Abstract: Properties of a porous solid sample 19, which may be a core of rock taken from below ground are carried out using apparatus which performs both nuclear magnetic resonance (NMR) and porosimetry measurements. The apparatus has a magnet 11,12 providing a magnetic field and a radio frequency coil 20 for transmitting and/or receiving electromagnetic radiation so as to bring about NMR in the magnetic field, a pressure vessel 14, 15 to hold a sample 19 within the magnetic field, a supply of a non-wetting liquid connected to the vessel, means to apply pressure to the non-wetting liquid to force liquid into pores of the sample 19 means to measure applied pressure of the non-wetting liquid and means to measure volume thereof taken up by the sample. The pressure of non-wetting liquid may be increased in steps, using intruded liquid volume at each step to give a measurement of pore throat size using NMR at each step to give a measure of pore size such as diameter of equivalent sphere.

Abstract: Apparatus for examining a fluid-containing porous sample, by a combination of centrifuging to move fluid into, out of, and/or within the sample and NMR to monitor the amount of fluid present at locations within the sample has a magnet system to provide a magnetic field; and a centrifuge rotor comprising a holder (18) for the sample and mounted to move the sample within the magnetic field. The apparatus preferably includes gradient coils (16, 116) superimposing a magnetic field gradient onto a field provided by magnets (11, 12, 111, 112). At least one radio-frequency coil (20) is located on the centrifuge rotor in a position 10 which surrounds the sample in the holder. The coil axis is transverse to the magnetic field and field gradient when measurement is made. Consequently NMR measurement of the distribution of fluid in the sample can be made while the centrifuge is in motion.

Abstract: A laboratory NMR methodology (and corresponding laboratory apparatus) defines a sample volume. The method stores downhole tool data corresponding to a hydrocarbon-bearing sample collected from a given subsurface formation. The downhole tool data includes parameters pertaining to magnetic fields used by a downhole tool during a suite of NMR measurements of the given subsurface formation. The sample is positioned in the sample volume of the laboratory apparatus, which applies a static magnetic field in the sample volume. Furthermore, the laboratory apparatus applies a suite of NMR measurements to the sample volume to thereby determine a property of the sample. The NMR measurements of the suite each include a pulse sequence of oscillating magnetic field in conjunction with a pulsed-mode gradient field. The pulsed-mode gradient field is based on the stored downhole tool data corresponding to the sample. A laboratory NMR methodology for optimizing downhole NMR measurements is also described.

Abstract: A laboratory NMR methodology (and corresponding laboratory apparatus) defines a sample volume. The method stores downhole tool data corresponding to a hydrocarbon-bearing sample collected from a given subsurface formation. The downhole tool data includes parameters pertaining to magnetic fields used by a downhole tool during a suite of NMR measurements of the given subsurface formation. The sample is positioned in the sample volume of the laboratory apparatus, which applies a static magnetic field in the sample volume. Furthermore, the laboratory apparatus applies a suite of NMR measurements to the sample volume to thereby determine a property of the sample. The NMR measurements of the suite each include a pulse sequence of oscillating magnetic field in conjunction with a pulsed-mode gradient field. The pulsed-mode gradient field is based on the stored downhole tool data corresponding to the sample. A laboratory NMR methodology for optimizing downhole NMR measurements is also described.

Abstract: The present invention describes a system and method for communicating voice and data over a packet-switched network that is adapted to coexist and communicate with a legacy PSTN. The system permits packet switching of voice calls and data calls through a data network from and to any of a LEC, a customer facility or a direct IP connection on the data network. The system includes soft switch sites, gateway sites, a data network, a provisioning component, a network event component and a network management component. The system interfaces with customer facilities (e.g., a PBX), carrier facilities (e.g., a LEC) and legacy signaling networks (e.g., SS7) to handle calls between any combination of on-network and off-network callers. The soft switch sites provide the core call processing for the voice network architecture. The soft switch sites manage the gateway sites in a preferred embodiment, using a protocol such as the Internet Protocol Device Control (IPDC) protocol to request the set-up and tear-down of calls.

Abstract: The present invention describes a system and method for communicating voice and data over a packet-switched network that is adapted to coexist and communicate with a legacy PSTN. The system permits packet switching of voice calls and data calls through a data network from and to any of a LEC, a customer facility or a direct IP connection on the data network. The system includes soft switch sites, gateway sites, a data network, a provisioning component, a network event component and a network management component. The system interfaces with customer facilities (e.g., a PBX), carrier facilities (e.g., a LEC) and legacy signaling networks (e.g., SS7) to handle calls between any combination of on-network and off-network callers. The soft switch sites provide the core call processing for the voice network architecture. The soft switch sites manage the gateway sites in a preferred embodiment, using a protocol such as the Internet Protocol Device Control (IPDC) protocol to request the set-up and tear-down of calls.

Abstract: The present invention describes a system and method for communicating voice and data over a packet-switched network that is adapted to coexist and communicate with a legacy PSTN. The system permits packet switching of voice calls and data calls through a data network from and to any of a LEC, a customer facility or a direct IP connection on the data network. The system includes soft switch sites, gateway sites, a data network, a provisioning component, a network event component and a network management component. The system interfaces with customer facilities (e.g., a PBX), carrier facilities (e.g., a LEC) and legacy signaling networks (e.g., SS7) to handle calls between any combination of on-network and off-network callers. The soft switch sites provide the core call processing for the voice network architecture. The soft switch sites manage the gateway sites in a preferred embodiment, using a protocol such as the Internet Protocol Device Control (IPDC) protocol to request the set-up and tear-down of calls.

Abstract: A heat sink disposable on a heat transfer surface of a heat-generating source such as an electronic component. The heat sink includes a base portion and a body portion. The base portion has a first surface disposable on the heat transfer surface, and a second surface opposite the first surface. The body portion is joined to the second surface of the base portion and is formed of a stack of corrugated sheets of one or more metal foils arranged to form a cellular, honeycomb-like structure.