A method includes operating a downhole acquisition tool in a wellbore in a geological formation. The wellbore or the geological formation, or both, contain a reservoir fluid. The method also includes receiving a portion of the reservoir fluid into the downhole acquisition tool and performing downhole fluid analysis using the downhole acquisition tool in the wellbore to determine at least one measurement associated with the portion of the reservoir fluid. The at least one measurement includes fluid density, optical density, or both. The method also includes using a processor of the downhole acquisition tool to obtain compressibility of the reservoir fluid based at least in part on the fluid density, the optical density, or both and determining a composition of the reservoir fluid based at least in part on the compressibility.

The present invention comprises a multi-modal security checkpoint. The security checkpoint can simultaneously scan for and simultaneously identify hidden metallics (e.g., weapons, shrapnel) and non-metallics (e.g., explosives, dielectrics). The security checkpoint performs scanning and identifying at a rate of 15 or more frames per second for all targets within the inspection area. The security checkpoint comprises blocks for sending and receiving radiation signals, the blocks comprising transmitters and/or receivers, the blocks being configured to share information to compare cross- and co-polarizations of signals emitted. The security checkpoint combines many threat detection technologies into one checkpoint that allows it to be robust and detect a large variety of threats in mass transit hubs requiring high throughput processing capabilities.

A method of surface logging a well includes adding each of multiple polymeric taggants to a circulating drilling fluid in an addition sequence while drilling the well. Each polymeric taggant includes a polymer and a respective fluorescent dye having an emission wavelength or excitation wavelength different from that of each other fluorescent dye. The method includes taking a sample of drill cuttings carried by a drilling fluid while drilling a well, wherein the sample of drill cuttings includes polymeric taggants attached to the drill cuttings. The method includes extracting the dyes from the sample of drill cuttings into an extract solution; determining an indication of the type of and the concentration of each of the dyes in the extract solution; and determining a depth associated with the sample of drill cuttings based on the indication of the concentration of each of the dyes and on the addition sequence.

A method of surface logging a well includes adding each of multiple polymeric taggants to a circulating drilling fluid in an addition sequence while drilling the well. Each polymeric taggant includes a polymer and a respective fluorescent dye having an emission wavelength or excitation wavelength different from that of each other fluorescent dye. The method includes taking a sample of drill cuttings carried by a drilling fluid while drilling a well, wherein the sample of drill cuttings includes polymeric taggants attached to the drill cuttings. The method includes extracting the dyes from the sample of drill cuttings into an extract solution; determining an indication of the type of and the concentration of each of the dyes in the extract solution; and determining a depth associated with the sample of drill cuttings based on the indication of the concentration of each of the dyes and on the addition sequence.

A system for measuring subterranean physical properties, in some embodiments, comprises a source of broadband light, an input optical fiber coupled to the source of broadband light, a wavelength division demultiplexer coupled to the input optical fiber, a plurality of detectors arranged in parallel and coupled to the demultiplexer, a wavelength division multiplexer coupled to the plurality of detectors, and an output optical fiber coupled to the multiplexer.

A system for measuring subterranean physical properties, in some embodiments, comprises a source of broadband light, an input optical fiber coupled to the source of broadband light, a wavelength division demultiplexer coupled to the input optical fiber, a plurality of detectors arranged in parallel and coupled to the demultiplexer, a wavelength division multiplexer coupled to the plurality of detectors, and an output optical fiber coupled to the multiplexer.

Monitoring a water intrusion condition at a facility comprises using an optical data transceiver to illuminate a monitored interior space with an optical data signal which has been modulated to contain a first data sequence. The optical data transceiver receives one or more retroreflected optical data signals which have been respectively retroreflected in response to the optical data signal. A water intrusion event notification is communicated to an enterprise monitoring controller if a variation occurs in regard to at least one optical beam condition associated with one or more of the retroreflected optical data signals.

Disclosed is the detection of emulsions and microdispersions with an optical computing device. One disclosed method includes emitting electromagnetic radiation from an electromagnetic radiation source, optically interacting the electromagnetic radiation with a fluid and thereby generating fluid interacted radiation, detecting a portion of the fluid interacted radiation with a reference detector arranged within an optical channel of an optical computing device, generating a reference signal with the reference detector, and determining an emulsive state of the fluid based on the reference signal.

Disclosed is the detection of emulsions and microdispersions with an optical computing device. One disclosed method includes emitting electromagnetic radiation from an electromagnetic radiation source, optically interacting the electromagnetic radiation with a fluid and thereby generating fluid interacted radiation, detecting a portion of the fluid interacted radiation with a reference detector arranged within an optical channel of an optical computing device, generating a reference signal with the reference detector, and determining an emulsive state of the fluid based on the reference signal.

A quasi-optical waveguide apparatus includes a waveguide having a chamber formed by a substantially cylindrical body and configured to propagate terahertz radiation. A plurality of windows are included wherein each window is coupled to a respective end of the waveguide such that the chamber is substantially sealed from the ambient atmosphere. The plurality of windows are transparent to the terahertz radiation.