69 results about "Radon exhalation" patented technology

Disclosed is a method for continuously measuring a radon exhalation rate in a close-loop mode. The method comprises the steps that in the measurement process, a radon collection cover with an opening in on face in a close-loop type measuring device is buckled on the surface of a medium to be measured, due to the fact that radon atoms in the medium to be measured overflow out of the surface and enter the radon collection cover under the action of diffusion and seepage, the radon concentration in the radon collection cover is changed, radon in the radon collection cover is pumped into a measurement cavity of a radon measuring instrument by a pump at the constant flow speed of 0.5-10 L/minute and returns to the radon collection cover, and the radon concentration of the measurement cavity in the radon measuring instrument and the radon concentration in the radon collection cover are balanced; then time T is used as the measurement period, the radon concentration in the radon collection cover is continuously measured and monitored, if the radon concentration is basically unchanged after the ith measurement period, nonlinear data fitting is carried out through the measurement values of the first i measurement periods and the relation of the radon concentration and the time of the i measurement periods to obtain the radon exhalation rate and the effective decay constant within the first i periods, and then the radon exhalation rate in all the periods is obtained by combining the effective decay constant previously obtained and later measurement data.

The invention discloses a method and a device for measuring a radon exhalation rate on a medium surface. The measuring method comprises a measuring process and a calculating process. The measuring method comprises the following steps: during measurement, inversely covering a radon accumulation chamber on the surface of a medium to be measured; connecting a sealed measuring chamber with the radon accumulation chamber to form a loop; after collecting a certain time period of 5 minutes, turning on an air pump to mix the radon in the radon accumulation chamber and the measuring chamber at a smallflow rate less than 3L/min for 5 minutes, wherein at this time, the radon concentration in the measuring chamber is the radon concentration in the radon accumulation chamber at the time T; repeatedlymeasuring the radon concentration in the radon accumulation chamber to obtain a group of data of radon concentration in the radon accumulation chamber at equal time intervals by taking T which is greater than or equal to 10 minutes as a period; and solving the radon exhalation on the surface of the medium to be measured according to a theoretical formula. The measuring device consists of the radon accumulation chamber, the air pump, the measuring chamber, a secondary instrument and a drying pipe, wherein one end of the air pump is connected with the radon accumulation chamber, while the otherend is connected with the measuring chamber through a pipe; one end of the drying pipe is connected with the radon accumulation radon through a pipe, while the other end is connected with the measuring chamber through a pipe; and the secondary instrument is connected with the measuring chamber.

A method for quickly measuring the radon exhalation rate in a closed-loop manner comprises a measurement process and a computation process. During the measurement process, a long time interval is adopted, that is, measurement is conducted once for every 5-120 min, and once measurement is a period. Through the adoption of measured data in two periods, an accurate radon exhalation rate can be obtained quickly through a simple computational method; during the measurement process, the two measurement periods are equal. A radon meter adopting the frequently-used electrostatic collection method actually measures the concentration of <218>Po and is obvious in measurement delay. When the radon meter adopting the frequently-used electrostatic collection method measures a variable radon concentration in a tracking manner, a measured value has to be corrected; through the correction on the measured value, an accurate radon exhalation rate can be obtained quickly.

The invention relates to an open-loop radon exhalation rate continuous measurement method by using an effective decay constant. The method includes the steps that the effective decay constant is measured before open-loop radon exhalation rate continuous measurement, and the radon exhalation rate is directly calculated through the effective decay constants. The method for measuring the effective decay constants includes the following steps that the radon exhalation rate is measured based on a preset flow rate of an emanometer (image file='865994 dest_path_image 001.TIF'wi='18'he='25'/); the flow rate of a pump is reduced, the radon exhalation rate is obtained at the flow rate ((image file='2014100522143100004 dest_path_image 002.TIF' wi='18'he='25'/), and if the difference between the measurement value of the radon exhalation rate at the moment and the measurement value of the radon exhalation rate at the flow rate (image file='845451 dest_path_image 001.TIF'wi='18'he='25'/) is small, the flow rate continues to be reduced until the difference is larger than or equal to 20%; the value of the effective decay constant is calculated according to the radon exhalation rate values obtained at the two different flow rates through the expression (7) (image file='625188 dest_path_image 003.TIF' wi='144'he='46'/); due to the fact that the value of the effective decay constant is known, the radon exhalation rate is obtained through direct calculation according to the expression (5) (image file='2014100522143100004 dest_path_image 004.TIF'wi='208'he='45'/) or the expression (6) (image file='82714 dest_path_image 005.TIF'wi='213'he='45'/).

The invention discloses an open-loop type method for measuring an effective decay constant and a radon exhalation rate synchronously. The method comprises a measurement process and a calculation process, analyzes radon concentration ascending curve data in a radon collection cover collecting chamber, corrects the existing calculation methods, and can obtain accurate radon exhalation rate through simple calculation. During the measurement process, the radon concentration is measured at short time interval, namely is measured every 2-10 minutes, and is measured for n periods till the radon concentration in the radon collection cover collecting chamber trends to be a constant value. During the calculation process, the radon concentration data of n periods obtained through measurement is defined as the radon concentration of the midpoint of the n periods, and a formula (7) is adopted for non-linear data fitting, thus the radon exhalation rate and the effective decay constant can be obtained synchronously.

The invention discloses a uranium mine exploration residual facility management and vegetation recovery method in high-cold high-altitude regions. The method comprises the following steps: 1) covering the land needing to be managed by soil; determining the thickness of a covering layer according to radon exhalation rate and penetrating radiation dose rate; and then covering the land needing to be managed; 2) carrying out slope protection and insulation on the covered managing land; 3) planting indigenous plants which do not adsorb radioactive nuclide on the covering layer, comprising locally collected wild weed seeds, plateau Tamarix chinensis and at least two of annual ryegrass, Elymus sibiricus cv. Chuancao No.1, dahusian wildrye, Poa pratensis, chewings fescue and white clover. The invention not only can meet the radiation protective requirements of inhibiting the radon exhalation rate and shielding the penetrating radiation dose rate, but also can ensure earlier stage stability of the covering layer and continue survival optimum succession of vegetation, thus ensuring that the management of the waste (ore) piles and the exploratory trenches in high altitude regions can achieve long-term stability and optimum ecological environment efficiency and economical efficiency.

An open-loop type quick measurement method of radon exhalation rate includes two measurement modes. In the first measurement mode, multiple shorter cycles which respectively last for 1-20 minutes are measured after a radon collection case is capped on the surface of a to-be-measured medium so that the radon concentration sequence is acquired, the measurement data of each cycle are approximately regarded as the concentration 218Po of the center point of each measurement cycle, and then the radon exhalation rate can be acquired by means of non-linear data fitting. In the second measurement mode, a longer cycle which lasts for 20-200 minutes is measured after the radon collection case is capped on the surface of the to-be-measured surface, and the radon exhalation rate can be solved by the aid of the measurement value of the longer measurement cycle according the formulas (14) and (15). The open-loop type quick measurement method of the radon exhalation rate is quick in measurement, and the radon exhalation rate can be obtained by calculation according to the measurement data before the radon in the radon collection case balances.

The invention provides a method and device for optionally adjusting radon exhalation rate and effective decay constants. During measurement, a solid radon source is placed on the plane of the adjusting device, an opening radon collecting cover of an existing device on the plane of the adjusting device, a plurality of small holes are formed in the plane of the adjusting device, the effective decay constants are adjusted by controlling the small holes to open and close, and the radon exhalation rate is adjusted by using the solid radon sources with different source strengths; the number of the small holes in the plane of the adjusting device is N, the diameter of the hole ranges from 0.1mm to 1mm, and the leakage coefficient of each hole is lambda leak1; if n small holes are sealed, the effective decay constants are calculated through a formula (4): lambda e = lambda + (N-n)* lambda leak1. The adjusting device adopted by the method comprises a plane and an adjusting plate.

A rapid measurement method of a radon exhalation rate through a closed-loop partial integration provided by the invention comprises a measurement process and a calculation process. In the measurement process, a short time interval is employed for measurement, namely the measurement is taken once every 2-10 minutes until the radon concentration in a radon collection cover collecting chamber trends toward a steady state value. In the calculation process, initial partial data of the ascent curve of the radon concentration in the radon collection cover collecting chamber is analyzed, an effective decay constant is neglected, and a simple algebraic operation is employed to correct the current calculation method, therefore an accurate radon exhalation rate may be quickly obtained.

The invention discloses a medium surface radon exhalation rate continuous measurement method and apparatus. The method includes the steps of Step 1 measuring the initial radon concentration C0; Step 2 calculating the medium surface radon exhalation rate; determining A, B and the equivalent decay constant lambda e through the following method: the relationship of radon concentration in a radon collection shield at the n and n-1 measurement is: Cn=A+BCn-1; (b1) in a radon cumulation process: as shown in the description; (b2) in a radon dynamic equilibrium process: as shown in the description. The medium surface radon exhalation rate continuous measurement method and apparatus can achieve continuous measurement and is high in measurement efficiency.

The invention provides a standard device and method for arbitrarily and actively adjusting radon exhalation rate and effective decay constant. The standard device comprises a panel, an adjustable micro pump, a flowmeter and an adsorption tube. The panel is provided with an inlet connector and an outlet connector. One end of the outlet connector on the panel is connected with an air inlet of the adjustable micro pump through a pipeline; an air outlet of the adjustable micro pump is connected with an air inlet of the flowmeter; an air outlet of the flowmeter is connected with an air inlet of the adsorption tube through a pipeline; an air outlet of the adsorption tube is connected with the inlet connector on the panel; an opening radon collection cover is covered on the panel, and the inlet connector and the outlet connector are covered in the opening radon collection cover. During measuring, a solid radon source is placed on the panel, and the opening radon collection cover is covered on the panel; and the effective decay constant [lambda]e is adjusted by controlling the flow rate of the adjustable micro pump, and the radon exhalation rate is adjusted through the solid radon sources with different activities.

The invention discloses a continuous measurement device and a measurement method for the radon exhalation rate. The continuous measurement device comprises a radon measurer, wherein the radon measurercomprises a gas storage tank; the continuous measurement device further comprises a controller and a radon collection hood; the radon collection hood is a hood body; a flow guide plate is arranged atthe inner top of the hood body; the size of the gas storage tank is 10% less than that of the radon collection hood; a gas feeding pipe is arranged at one end of the radon collection hood, and a gasdischarging pipe is arranged at the other end of the radon collection hood; the radon measurer is arranged on the gas discharging pipe, and is connected with the controller; the continuous measurementdevice further comprises an air flow measurement and control unit, a drying system, a sensor group, a GPRS system and a power supply unit. The continuous measurement device can change the state of the environment of a measurement position; the humidity of measured gas is controlled by the drying system; the gas with high gas flow becomes uniform through the flow guide plate; the radon concentration in the radon collection hood is adjusted through a controllable gas pump, so that a measurement process is in a state free of interference caused by the humidity, the radon concentration and a radon inverse diffusion coefficient, and the measurement precision is improved.

This invention involves a locale multi-channel alphaspectroscopy measuring instrument for radon separation rate and radon concentration, including radon collection devices, semiconductor detectors, charge-sensitive amplifier, the main amplifier, multi-channel analyzer. In the multi-channel analyzer there has USB interface. Through the USB interface the multi-channel analyzer is linked with notebook computers. Through notebook computers we can control alpha continuous spectrum measurement and display the entire spectrum. The measuring instrument of alpha spectrum also adopts on-line and real-time spectrum-stabilizing to stabilize spectrum regulation. At the scene with the conditions of great changes in temperature and humidity, and poor measurements conditions, this invention will still ensure the stability, reproducibility and accuracy of dynamic measurement. The invention can be used in tailings surface, soil, ground, building materials, nuclear facilities places surface radon exhalation rate of -alpharay spectrometry, and can also be used for environmental radon concentration measurement and solving the tailings management-side management measure.

The invention discloses a permeability enhancement and lixiviation test system for low-permeability uranium-bearing sandstone. The test system comprises a water and air supply system, a high- and lowfrequency excitation system, a lixiviation system and a data acquisition system. With the test system adopted, the permeability enhancement and lixiviation, and radon exhalation of the low-permeability uranium-bearing sandstone can be tested under the effects of different vibration frequencies, vibration time, temperature and the inflation pressure of carbon dioxide and oxygen; and the influence of the change of the vibration frequencies, vibration time, temperature and the inflation pressure of the air on the radon exhalation of a particle uranium-bearing material and a bulk uranium-bearing material under the action of vibration can be tested. According to the permeability enhancement and lixiviation test system for low-permeability uranium-bearing sandstone of the invention, ultrasonic waves and sound waves are utilized to vibrate a sample; the porosity of the sandstone can be increased; the flow of a liquid can be accelerated; the contact between the uranium-bearing sandstoneand the liquid is accelerated; the lixiviation rate of uranium is increased; the change of radon content during a vibration lixiviation process is detected; an assessment basis can be provided for environmental pollution caused by radon; and experimental study on a pollution problem caused by the radon exhalation of ground surface uranium-bearing materials during a stacking process under the influence of air pressure, temperature and vibration can be carried out.

The invention discloses a method and device for measuring the emanation medium radon exhalation rate in an open-loop mode. According to the method, the measurement of the radon exhalation rate is carried out by using the device. The device comprises a radon measuring instrument and a test column used for containing a to-be-tested emanation medium, a gas collecting cover is arranged above the testcolumn, the gas inlet of the radon measuring instrument is communicated with the gas collecting cover through an air pipe, the gas outlet of the radon measuring instrument is communicated with an external environment, a hole communicated with the external environment is formed in the upper surface of the gas collecting cover, a gas pressure equalizing chamber is arranged below the test column, thegas pressure equalizing chamber is connected with a gas pump through the gas pipe, and a flow regulator is arranged on the gas pipe between the gas pressure equalizing chamber and the gas pump. The method has the advantages that the free diffusion of the radon on the surface of the medium is considered, and the influence of the seepage effect is also considered. In addition, the device can accurately measure the radon exhalation rate of the surface of the medium in a short time.

The invention belongs to the technical field of building materials, and discloses a shale brick processing process with a low radon exhalation rate. The process comprises the following steps: smashing and sieving the raw materials, shale brick and gangue and then mixing the obtained product; and pressing, forming, drying and roasting the mixed product to obtain the shale brick. The key point lies in that the shale brick and the gangue are smashed till the particle size is less than 2 mm; the negative pressure is less than 85 kPa during the pressing and forming; the mixing rate of the shale brick and the gangue is 3:2-1:1; the drying temperature is 80 to 100 DEG C; and the roasting temperature is 1,000 to 1,020 DEG C. The process can decrease the radon exhalation rate and the indoor radon concentration from the source and reduce radiation for residents.

A test apparatus and a test method for radon exhalation rate of building bulk material and radon exhalation rate during neutralization. The test apparatus includes a building bulk material box, a boxcover, a seal board, a test sample holder, a radon detector, a drying pipe, and a hose. The box cover covers the building bulk material box. A gas inlet of the drying pipe is connected to a gas outletpipe on the box cover and a gas outlet of same is connected to the inlet of the radon detector; the gas outlet of the radon detector is connected to the gas inlet pipe on the box cover. During radonexhalation rate test, the building bulk material is placed on the test sample holder in the box and the radon detector detects radon entering a test chamber; according to a radon concentration increase curve, radon exhalation rate of the building bulk material in different time sections is obtained; during radon exhalation rate during neutralization, the seal board is placed on the building bulk material and is sealed with sealant; then a NaHCO3 saturated solution is added and the radon detector detects radon entering the test chamber; according to the radon concentration increase curve, the radon exhalation rate of the building bulk material in different time sections during the neutralization.

The invention discloses a test chamber for the radon exhalation rate in soil, and belongs to a detection device in soil radon prevention research. The test chamber is characterized by comprising a chamber cover and a chamber body. A clamping device is arranged between the chamber cover and the chamber body. High-radon soil is filled in the chamber body, and a plurality of radon sampling boxes are embedded in the high-radon soil. A concrete ground model component and a concrete construction model component cover on the high-radon soil. A space is reserved between the concrete ground model component and the concrete construction model component and the chamber cover to form an air chamber. A plurality of air inlet/outlet nozzles are arranged on the chamber wall at the position of the air chamber of the chamber body, and the radon sampling boxes are connected to the plurality of air inlet/outlet nozzles which are distributed on the chamber wall through radon sampling pipelines. Through the test chamber, the earth and constructions are moved indoors for research, and the test chamber can simulate to test the indoor radon concentration of construction models under various environmental conditions, greatly improves the research efficiency, reduces the radon-preventing cost, and improves the radon-preventing effect.

The invention discloses a method for estimating the surface radon emanation rate of in-situ leaching uranium evaporation pool, which comprises the following steps: based on the active diffusion of radon in medium and the passive diffusion of seepage flow, establishing a theoretical calculation formula, based on the theoretical calculation formula, obtaining an estimation result, and modifying theestimation result by a source term inversion method based on a BP neural network. The theoretical formula of radon exhalation rate is established by this method, considering the active diffusion of radon and the passive diffusion of seepage in the medium synthetically, the BP neural network is used to study the monitoring data and establish the source term inversion method. The predicted data areused to revise the calculation results of the preliminary established estimation method. The method fills the research blank and realizes the accurate estimation of radon emission rate.

The invention discloses a radon exhalation simulation device and a radon exhalation rate measurement method. The radon exhalation simulation device comprises a radon exhalation tank, a radon measuringinstrument and a low frequency vibration module, a uranium-like ore sample is packaged in the radon exhalation tank, a radon collection space is formed in the uranium-like ore sample, a gas inlet ofthe radon measuring instrument communicates with a gas outlet end of the radon collection space, and a gas outlet of the radon measuring instrument communicates with a gas inlet end of the radon collection space; the radon exhalation simulation device further comprises a wind pressure adjustment module for adjusting the wind pressure in the radon collection space, the wind pressure adjustment module comprises an air blower, a blast pipe and an air outlet pipe, the air blower communicates with the gas inlet end of the radon collection space through the blast pipe, the air outlet pipe communicates with the gas outlet end of the radon collection space, and a pressure sensor is arranged in the radon collection space. In the radon exhalation simulation device disclosed by the invention, the wind pressure in the radon collection space is adjusted via the wind pressure adjustment module, the wind pressure is detected by the pressure sensor, the low frequency vibration module is used for applying a low frequency vibration load to a radon exhalation module to simulate the mechanical vibration of a surrounding rock of a roadway of a uranium ore, and the real simulation of the roadway of theuranium ore under a press-in ventilation condition is achieved.

The invention provides a measurement apparatus of a radon exhalation rate and a measurement method thereof and belongs to the nuclear radiation detection technology field. A box body of a gas generation apparatus is filled with water. An upper end of the box body is connected to a water inlet pipe. A lower end of the box body is connected to a water outlet pipe. An arc groove whose bottom portion is cooperated with an outer wall of a test piece is immersed in the box body. A liquid coupling agent is arranged in the arc groove. The test piece is horizontally placed in the arc groove. Two ends of the test piece are sealed by sealing plates. An ultrasonic device comprises an ultrasonic generator, a control switch and a plurality of ultrasonic vibrators. The ultrasonic vibrators are uniformly arranged on a bottom surface of the box body. The control switch is electrically connected to the ultrasonic vibrators and the ultrasonic generator through a cable. An external-connection accessory comprises an emanometer, a first branch pipe, a second branch pipe, the emanometer, a pressure meter, a pressure pump and a sucking pump. The apparatus is integrated with the ultrasonic device, the emanometer, a pressure generation device and the like. Pressure and an ultrasonic frequency are controllable and adjustable. Operability of the whole set of apparatus is high, reliability is high too and usage is convenient.