34 results about "Gamma gamma" patented technology

A scintillator crystal (26)=based gamma-ray camera system is described. The gamma-ray camera system includes a spectra processing component for (34) providing improved energy resolution over that seen in conventional gamma-ray camera systems. The spectra processing component operates to deconvolve detector response functions from observed energy spectra on a pixel by pixel basis. The pixel dependent to detector response functions are obtained by a combination of theoretical simulation, and empirical calibration. By deconvolving pixel specific detector response functions, variations in response of a gamma-ray camera system across its image plane can be accounted for. This offers significant improvements in energy resolution and many of the problems associated with conventional gamma-ray camera systems are reduced. For example, the improved energy resolution allows better rejection of photons associated with Compton scattering events occurring in a source being imaged. This is because a narrower energy window filter can be used without rejecting a significant fraction of non-Compton scattered photons. The spectra processing component can be easily implemented with different types of gamma-ray imagers, for example Anger-type cameras, and may also be retroactively fitted to existing gamma-ray camera systems.

The invention discloses a novel system and method of measuring concentration of radon in water. The novel system of measuring concentration of radon in water includes successively connected first Gamma detector, first linear amplifier, first single-channel pulse-height analyzer, first delay shaping circuit and first scaler, and successively connected second Gamma detector, second linear amplifier,second single-channel pulse-height analyzer, second delay shaping circuit and second scaler, wherein the output terminal of the first delay shaping circuit and the output terminal of the second delayshaping circuit are connected to the input terminal of a coincidence circuit; the coincidence output terminal of the coincidence circuit is connected with a third scaler; the novel system of measuring concentration of radon in water also includes a calculation module which is used for calculating the activity concentration C<222><Rn>: C<222><Rn>=n<Gamma Gamma 1> - n) / V<Elipson> <Gamma Gamma>of 222Rn in a sample to be measured, wherein n<Gamma Gamma 1> is the counting rate of the third scaler during the process of measuring the sample to be measured; n is the background counting rateof the third scaler; V is the volume of the sample to be measured; and Epsilon <Gamma Gamma> is the detection efficiency of a coincidence channel. The novel system and method of measuring concentration of radon in water can quickly reduce the measurement background and can achieve the effect of quickly and accurately measuring the concentration of radon in water.

A downhole gamma ray density measurement system is described. The gamma ray density measurement system includes a pressure housing and a gamma ray source within the pressure housing. One or more detectors within the pressure housing detect gamma radiation. One or more low-attenuation inserts may be located in the pressure housing near the gamma ray source and / or one or more of the detectors. One or more high-attenuation inserts may be located in the pressure housing near the gamma ray source and / or one or more of the detectors.

The invention relates to a Gamma-Gamma distribution parameter estimation method based on a double logarithmic cumulant expectation, and belongs to the technical field of atmospheric turbulence channel parameter estimation of free space optical communication systems. According to the method, a Gamma-Gamma distribution parameter estimation process is simplified greatly through Mellin transform, and a uniform parameter estimation method is built specific to the problems of low fractional moment (FMOM) parameter estimation accuracy and even error estimation in the prior art. Then, further improvements are made, and a concept of double logarithmic cumulant expectation is put forward, so that a finial parameter estimation expression is deduced. Compared with an FMOM, the Gamma-Gamma distribution parameter estimation method has the advantages that relatively high computing efficiency is ensured, and the parameter estimation accuracy is increased.

A method for performing a measurement of a property downhole includes: using an instrument including an irradiator including a pulsed neutron generator, a moderator and a material including a high cross section for capturing thermal neutrons downhole, generating inelastic gamma photons from neutron interactions in the moderator and generating capture gamma photons from neutron interactions in the material; irradiating sub-surface materials proximate to the instrument with the inelastic gamma photons and the capture gamma photons; detecting radiation scattered by the sub-surface materials; and estimating the property according to the detected radiation. A system is also disclosed.

A scintillator crystal (26) based gamma-ray camera system is described. The gamma-ray camera system includes a spectra processing component for (34) providing improved energy resolution over that seen in conventional gamma-ray camera systems. The spectra processing component operates to deconvolve detector response functions from observed energy spectra on a pixel by pixel basis. The pixel dependent to detector response functions are obtained by a combination of theoretical simulation, and empirical calibration. By deconvolving pixel specific detector response functions, variations in response of a gamma-ray camera system across its image plane can be accounted for. This offers significant improvements in energy resolution and many of the problems associated with conventional gamma-ray camera systems are reduced. For example, the improved energy resolution allows better rejection of photons associated with Compton scattering events occurring in a source being imaged. This is because a narrower energy window filter can be used without rejecting a significant fraction of non-Compton scattered photons. The spectra processing component can be easily implemented with different types of gamma-ray imagers, for example Anger-type cameras, and may also be retroactively fitted to existing gamma-ray camera systems.

Embodiments are directed to image processing methods to improve display quality while using a limited number of pulses and to correct the error between the reflectance and the desired gamma. The complexity of the hardware used for driving a display device may then be reduced to minimum. In addition, in various embodiments the method can also be used to compensate for the change of an optical response curve due to batch variation, temperature change, photo-exposure or aging of the display device.

A visual photographic camera is utilized in a fixed geometric relationship together with another imaging or treatment source such as a standard gamma-camera or an x-ray source. The visual camera is either attached to the gamma camera gantry, the gamma camera head or mounted on a structure such as the ceiling in the imaging room. After the standard gamma camera image is obtained, the gamma-camera head can rotate either bringing the visual camera over the patient, or moving out of the way to expose the patient to the field of view of the gantry-mounted or ceiling mounted camera. On the fusion image, both the visual and scintigraphic parameters for each specific location on the patient's body may be coded in a display. The visual camera may be utilized together with x-ray imaging equipment. In that application, the visual camera could either be attached to the x-ray tube assembly, or be mounted on a structure in the imaging room. Based on a fixed relationship between the location of the x-ray machine and the photographic camera, the two images could be scaled and superimposed to generate a ‘fusion’ image.

The invention discloses a method for calculating the average channel capacity of an FTN transmission system on the condition of double Gamma turbulence channels, and aims to introduce an FTN technology into a Gamma-Gamma turbulence channel, so that the symbol rate is greater than the Nyquist rate, the average capacity of the system is effectively improved, and the performance of an atmospheric transmission system is improved. The FTN signal is formed by performing QPSK mapping on input bit information an and then generating the FTN signal through an FTN shaping filter. The system channel capacity is obtained by using a received signal transmission model, and then normalizing the period of the channel capacity to obtain the average capacity of the FTN system. On the basis, an expression ofthe average capacity of the super-Nyquist optical transmission system under a Gamma-Gamma turbulence channel under a QPSK modulation format is derived according to QPSK modulation characteristics. Theconstruction of the super-Nyquist optical transmission system effectively improves the spectral efficiency of the system.

A method for measuring radiation in a borehole, the method including placing a detector comprising a scintillator and a plurality of photodetectors in the borehole; detecting a radiation interaction with a first photodetector; detecting the radiation interaction with at least a second photodetector; and determining a location of the interaction from the detecting; wherein the location provides information regarding formations surrounding the borehole.

A method for a pulsed gamma-gamma density tool to simultaneously compensate for interactions due to the photoelectric effect and density variations caused by standoff enables a more precise determination of bulk formation density. This method includes the steps of providing a source of energetic particles and directing those energetic particles at a formation having a known photoelectric factor and electron density and capturing one or more photons either emitted or deflected from the formation either a first detector or a second detector. The first detector is spaced a first distance from the source, the second detector is spaced a second distance from the detector and a third distance separates the first detector from the second detector. Measuring a first total energy of the photons striking the first detector during a time interval and measuring a second total energy of the photons striking the second detector as a function of the time interval and disposing a first filter between the first detector and the formation effective to cause Pe response to match standoff influence thereby compensating for both effects simultaneously. In addition to the first filter, the required compensation may include a second filter between the second detector and the formation as well as adjustments to the respective first distance, second distance and third distance.

The invention discloses a pressurized water reactor primary coolant circuit boundary leakage monitoring method and system as well as a monitoring instrument. The method comprises the following steps:on a sampling point, acquiring sampling gas in a safety shell by virtue of a sampling pipeline, and transporting the sampling gas into a sampling container; detecting gamma-gamma coincidence countingof gamma-gamma photons opposite to the emitted direction of beta+ decay of 13N in the sampling gas of the sampling container by virtue of a coincidence detection apparatus, and calculating and outputting a gamma-gamma coincidence counting rate, wherein the coincidence detection apparatus comprises at least two coincidence detectors; and according to the gamma-gamma coincidence counting rate in thesampling gas, determining a leakage rate of cooling agent water on the pressurized water reactor primary coolant circuit boundary, so that the pressurized water reactor primary coolant circuit leakage can be accurately and efficiently monitored.

A method for measuring radiation in a borehole, the method including placing a detector comprising a scintillator and a plurality of photodetectors in the borehole; detecting a radiation interaction with a first photodetector; detecting the radiation interaction with at least a second photodetector; and determining a location of the interaction from the detecting; wherein the location provides information regarding formations surrounding the borehole.

A natural gamma tag marking materials for sub or permanent markers used in gamma logging operations, such natural gamma materials having a gamma count of between 200 and 1000 counts per second. The instant invention further discloses a typical Sub, for insertion in a drilling operation, utilizing natural gamma element compounds which are considered to be non-hazardous and effective as tag markers when used in wire-line logging operations.

A gamma adjustment method for a display device having a gamma conversion table of an input signal, the method comprising: selecting a plurality of sampled gray levels among the gray levels of the input signal; Sampling the brightness level of the output video signal related to the gray level; determining a first gamma conversion value corresponding to the sampling gray level based on the measured brightness level and storing the determined gamma conversion value; Calculating a second gamma conversion value corresponding to the gray level of the input signal excluding the sampled gray level based on the gamma conversion value corresponding to the gray level; and based on the stored first gamma conversion value and the calculated The second gamma transform value to set the gamma transform table.

A system for measuring the density of a fluid in a vessel, the system including: at least one gamma-ray source positioned proximate to the vessel; at least one gamma-ray detector positioned proximate to the vessel, wherein the at least one gamma-ray detector is configured to detect gamma rays backscattered by the fluid from the at least one gamma-ray source; and a translator for converting the detected gamma-ray backscatter to a density value. A method to determine properties of a fluid in a vessel, the method including: positioning a gamma-ray source proximate to the vessel; positioning a gamma-ray detector proximate to the vessel; detecting gamma rays backscattered by the fluid from the gamma-ray source with the gamma-ray detector; determining a density of the fluid based upon an intensity of backscattered gamma rays received by the gamma-ray detector.

The invention belongs to the field of nuclear physics research and application, and specifically relates to a gamma-gamma density logging distorted curve correction method. The invention provides a correction method for eliminating gamma-gamma density logging curve distortion produced due to rock radiation in the stage of gamma-gamma density logging data sorting. The method comprises the following steps: S1, selecting a correction depth section; S2, calculating the density value of a rock skeleton; S3, calculating the average correction coefficient value; and S4, calculating the rock density of the correction depth section and drawing a corrected gamma-gamma density curve. The problem that a curve fluctuates drastically in a uranium enrichment section before correction is solved. Accurate acoustic impedance data can be provided for seismic exploration, and the quality of gamma-gamma density logging can be monitored effectively. The correction method is also applicable to a gamma-gamma density logging distorted curve affected by a hole enlarge section and a hole collapse section.

The invention is directed to apparatus for measuring mass flow-rates of the gas, oil and water phases in a wet gas, comprising the following parts: a differential pressure flow meter, having a throat section, and a gamma ray detector, comprising a gamma ray emitter and a gamma ray receiver that are arranged in such a manner that gamma rays emitted from the gamma ray emitter can pass through the throat section in diametrical direction to reach the gamma ray receiver; wherein a radioactive source in the gamma-ray emitter is a multi-energy radioactive source that can naturally emit at least three energy gamma rays, and a thermostatic device is not used in the gamma ray receiver. The invention further relates to a metering method for measuring mass flow-rates of the gas, oil and water phases in a wet gas, in which the above apparatus is used. As for the apparatus according to the invention, neither a thermostatic device nor the calibration for the empty tube value is in need, and thus it is very suitable for the uses under water or down-hole.

The invention relates to a methotrexate dosage regimen determining method, a device, a storage medium and equipment. Through establishing a methotrexate inner metabolism dynamics model, in consideration of influence of different methotrexate metabolism related enzymes (folypolyglutamate synthetase and gamma-gamma-glutamyl hydrolase) contents to the methotrexate metabolism speed parameter, and thenthe metabolism condition of the methotrexate is simulated through the model, thereby determining the corresponding dosage regimen according to the methotrexate metabolism simulation condition, namelydetermining the dosage regimen according to the methotrexate metabolism related enzyme content differences between different patient individuals, thereby realizing more scientific and reasonable methotrexate dosage regimen, and realizing accurate medicament dispensing for aiming at different patient individuals.

The invention discloses a gamma radiation detector, which includes a crystal system, a gamma probe and a processing system, and the gamma probe includes a gamma detection element, a photoconductor, a photodiode and a charge-sensitive preamplifier circuit connected in sequence . The output end of the charge-sensitive preamplifier circuit is connected to the electronic signal input end, and the crystal system includes an externally sheathed crystal encapsulation shell, the crystal encapsulation shell is arranged in the shell of the detector, and wraps the gamma probe A half-moon-shaped lead shielding body is arranged in the gap between the crystal package shell and the outer shell of the detector, and the processing system includes an amplifier, a discriminator, a counter, a controller, a display screen and a power supply module, wherein the signal of the amplifier The input end is connected to the signal output end of the gamma probe, the display screen is connected to the controller, and the power supply module supplies power for the amplifier, discriminator, counter, controller, and display screen, thereby improving detection accuracy.

The invention relates to a Gamma-Gamma distribution parameter estimation method based on a double logarithmic cumulant expectation, and belongs to the technical field of atmospheric turbulence channel parameter estimation of free space optical communication systems. According to the method, a Gamma-Gamma distribution parameter estimation process is simplified greatly through Mellin transform, and a uniform parameter estimation method is built specific to the problems of low fractional moment (FMOM) parameter estimation accuracy and even error estimation in the prior art. Then, further improvements are made, and a concept of double logarithmic cumulant expectation is put forward, so that a finial parameter estimation expression is deduced. Compared with an FMOM, the Gamma-Gamma distribution parameter estimation method has the advantages that relatively high computing efficiency is ensured, and the parameter estimation accuracy is increased.

The invention discloses a tomographic gamma scanning and measuring method which comprises the following steps of: 1, performing transmitting measurement on a sample, namely (1) positioning and axially layering the sample; (2) selecting translation position points in equal interval on each layer; (3) rotating the sample around the central axis of a platform at each horizontal translation position point, and selecting eight rotating angles between 0 and 180 degrees in equal angle, wherein once measurement is performed while rotating once, and eight-time measurement is performed at each horizontal position point; 2, performing emission measurement on the sample; and 3, correcting the absorption attenuation of emitted gamma rays which penetrate through the measured sample by utilizing a dielectric wire attenuation coefficient obtained through transmitting gamma scanning measurement, and obtaining the radioactive content. The invention provides the tomographic gamma scanning and measuring method which is short in measurement time, high in analytical precision and high in measurement accuracy.

The invention provides a liquid crystal display device and a display device. The display device includes a display unit, a common voltage generation circuit, a gamma correction circuit, a drive circuit and a power conversion circuit. The common voltage generating circuit provides the common voltage to the display unit. The gamma correction circuit outputs a gamma voltage. The driving circuit provides grayscale voltages to the display unit according to the gamma voltage. The power conversion circuit includes a first conversion circuit and a second conversion circuit. The first and second conversion circuits are both input ends for connecting with a power supply, and the rest are two parallel branches separated from each other and not connected to each other. The first conversion circuit generates a first power supply voltage, the second conversion circuit generates a second power supply voltage, and the first and second power supply voltages are respectively output to the gamma correction circuit and the common voltage generation circuit. The gamma correction circuit uses the first power supply voltage as a reference voltage to generate a gamma voltage. The common voltage generation circuit generates a common voltage with the second power supply voltage as a reference voltage.

The invention discloses a multi-purpose tender coconut essence which is characterized by being composed of 0.05%-0.5% of n-butanol, 1%-5% of trans-2-hexenal, 0.3%-8% of leaf alcohol, 0.1%-0.6% of ethyl butyrate, 0.05%-0.2% of benzaldehyde, 0.06%-0.1% of ethyl caproate and 0.01%-0.15% of acetic acid and the like. According to the multi-purpose tender coconut essence, plenty of natural coconut milkis taken as a backing material, the leaf alcohol, cis-3-hexenyl acetate, cis-3-hexenal and trans-3-propyalacrolein coconut green peel fragrance raw material are added, gamma-gamma-nonanoic lactone andbutyl-octanolactone coconut meat and coconut juice fragrance raw materials are added, the coconut fragrance is made mellow and full well, the fragrance of the green coconut peel and fragrance of coconut juice and coconut meat are combined pleasantly, and thus the perfect, fragrant and tasty and refreshing coconut flavor is formed. In addition, the natural coconut milk in the essence is high in content, and natural oil lemon oil is added in the overall aroma for modification, so that the coconut fragrance is more natural, fuller and richer, which is in line with the trend that the essence tends to be natural and healthy.

The present invention discloses a gamma density rapid-calculation method based on a perturbation theory, and specifically relates to the field of petroleum and natural gas development. According to the method, from a gamma-gamma density response principle, the perturbation theory is introduced to a density response, different standard densities of strata are selected as a reference, and an instrument-stratum model is established in combination with MCNP for simulation to obtain first-order and second-order Compton and photolectric sensitivity function databases, thus forming a gamma-gamma density rapid-calculation method at last. The method specifically includes the following steps: step 1: introducing the perturbation theory into the density response, and performing expansion, deformationand simplification on a formula to obtain a spatial dynamic response function expression form; step 2: according to a parameter of a selected gamma-gamma density instrument, establishing a three-dimensional MCNP numerical calculation model, and simulating to obtain a spatial dynamic response function database; and step 3: performing multielement nonlinear regression on multiple hybrid density responses, and seeking for a coefficient of a rapid calculation formula to obtain the rapid calculation formula for density.