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M. Weierganz

Publications and source records attributed to M. Weierganz.

6 recordsLinked to original sources

A method for rapid determination of oil and water content in geological formations

A novel method utilizing Fast Neutron Resonance Transmission Radiography is proposed for rapid, non-destructive and quantitative determination of the weight fractions of oil and water in cores taken from subterranean or underwater geological formations. Its ability to distinguish water from oil stems from the unambiguously-specific energy-dependence of the neutron cross-sections for the principal elemental constituents. Furthermore, the fluid weight fractions permit determining core porosity and oil and water saturations. In this article we show results of experimental determination of oil and water weight fractions in 10 cm thick samples of Berea Sandstone and Indiana Limestone formations, followed by calculation of their porosity and fluid saturations. The technique may ultimately permit rapid, accurate and non-destructive evaluation of relevant petro-physical properties in thick intact cores. It is suitable for all types of formations including tight shales, clays and oil sands.

physics.geo-ph

Quantitative discrimination between oil and water in drilled bore cores via fast-neutron resonance transmission radiography

A novel method based on Fast Neutron Resonance Transmission Radiography is proposed for non-destructive, quantitative determination of the weight percentages of oil and water in cores taken from subterranean or underwater geological formations. The ability of the method to distinguish water from oil stems from the unambiguously-specific energy dependence of the neutron cross-sections for the principal elemental constituents. Monte-Carlo simulations and initial results of experimental investigations indicate that the technique may provide a rapid, accurate and non-destructive method for quantitative evaluation of core fluids in thick intact cores, including those of tight shales for which the use of conventional core analytical approaches appears to be questionable.

physics.geo-ph

Parameters Affecting Temporal Resolution of Time Resolved Integrative Optical Neutron Detector (TRION)

The Time-Resolved Integrative Optical Neutron (TRION) detector was developed for Fast Neutron Resonance Radiography (FNRR), a fast-neutron transmission imaging method that exploits characteristic energy-variations of the total scattering cross-section in the En = 1-10 MeV range to detect specific elements within a radiographed object. As opposed to classical event-counting time of flight (ECTOF), it integrates the detector signal during a well-defined neutron Time of Flight window corresponding to a pre-selected energy bin, e.g., the energy-interval spanning a cross-section resonance of an element such as C, O and N. The integrative characteristic of the detector permits loss-free operation at very intense, pulsed neutron fluxes, at a cost however, of recorded temporal resolution degradation. This work presents a theoretical and experimental evaluation of detector related parameters which affect temporal resolution of the TRION system.

physics.ins-det

Development of an LED reference light source for calibration of radiographic imaging detectors

A stable reference light source based on an LED (Light Emission Diode) is presented for stabilizing the conversion gain of the opto-electronic system of a gamma- and fast-neutron radiographic and tomographic imaging device. A constant fraction of the LED light is transported to the image plane of the camera and provides a stable reference exposure. This is used to normalize the images during off-line image processing. We have investigated parameters influencing the stability of LEDs and developed procedures and criteria to prepare and select LEDs suitable for delivering stable light outputs for several 100 h of operation.

physics.ins-det

A Dual-Purpose Ion-Accelerator for Nuclear-Reaction-Based Explosives-and SNM-Detection in Massive Cargo

A dual-purpose ion-accelerator concept, capable of serving as radiation source in a versatile, nuclear-reaction-based cargo inspection system, is presented. The system will automatically and reliably detect small, operationally-relevant quantities of concealed explosives and special nuclear materials (SNM). It will be cost-effective, employing largely-common hardware, but different reactions/DAQ-modes. Typical expected throughput is 10-20 aviation containers/hr. PACS: 25.20.Dc; 25.40.Ny; 27.20.+n; 29.27.Fh; 79.77.+g; 89.20.Bb; 89.20.Dd Keywords: Cargo inspection; Nuclear-reaction-based methods; Explosives detection; SNM detection

nucl-ex

High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.

physics.ins-det