CN206515476U - A kind of neutron tube - Google Patents
A kind of neutron tube Download PDFInfo
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- CN206515476U CN206515476U CN201621358246.7U CN201621358246U CN206515476U CN 206515476 U CN206515476 U CN 206515476U CN 201621358246 U CN201621358246 U CN 201621358246U CN 206515476 U CN206515476 U CN 206515476U
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- 229910052580 B4C Inorganic materials 0.000 claims description 25
- INAHAJYZKVIDIZ-UHFFFAOYSA-N boron carbide Chemical compound B12B3B4C32B41 INAHAJYZKVIDIZ-UHFFFAOYSA-N 0.000 claims description 25
- 238000000576 coating method Methods 0.000 claims description 21
- 239000011248 coating agent Substances 0.000 claims description 20
- ZOXJGFHDIHLPTG-BJUDXGSMSA-N Boron-10 Chemical compound [10B] ZOXJGFHDIHLPTG-BJUDXGSMSA-N 0.000 claims description 7
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 6
- 229910052796 boron Inorganic materials 0.000 claims description 6
- 229910052810 boron oxide Inorganic materials 0.000 claims description 4
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 claims description 4
- 230000000155 isotopic effect Effects 0.000 claims description 3
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- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
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Abstract
The utility model provides a kind of new neutron pipe and matched preamplifier, so as to obtain that a kind of cost is low, be easy to make, the interference of anti-gamma-rays and long working life, the neutron tube of steady operation and other merits and have the advantages that small volume, reliable operation, the preamplifier that the signal shaping time is short, signal to noise ratio is high.
Description
Technical field
The utility model belongs to precision instrument and equipment manufacture field, and in particular to a kind of neutron tube and preamplifier.
Background technology
Neutron is non-having electronic particle, and the secondary charged particle that neutron to be passed through is produced with matter interaction is detected to it
Detect to realize.The detection for neutron mainly has following four method at present：Nuclear reaction method, the method for nuclear recoil, nuclear fission method and
Neutron activation method.
First, nuclear reaction method：Neutron is not charged in itself, does not occur coulomb interaction with atomic nucleus, therefore is easily accessible atomic nucleus,
Generation nuclear reaction.Selection can produce the nuclear reaction of charged particle, and excitation signal is ionized caused by charged particle by detecting, real
Now to the detection of neutron.This method is mainly used in detecting the intensity of slow neutron, also can be used to measure fast neutron under individual cases
Power spectrum.What application was most at present is following three kinds of nuclear reactions：
n+10B→α+7Li+2.792MeV σ=3837 ± 9b
n+6Li→α+3T+4.786MeV σ=940 ± 4b
n+3He→p+3T+0.765MeV σ=5333 ± 7b
Neutron and other nuclear reaction sections are usually several barns, because above-mentioned three kinds of reaction cross-sections are all very big, often
Neutron is detected using these three nuclear reactions.It is most widely used at present to be10B (n, α) reacts, because the material of boron -10 compares appearance
Easily obtain.Gaseous optional BF3Gas, the optional boron oxide or boron carbide of solid-state.Li does not have suitable gaseous compound,
Solid material can only be used when using；Wherein it is based on6The large area location-sensitive of LiF/ZnS scintillators and ripple shifting fiber structure
Thermal-neutron detector has turned into study hotspot in recent years.3He (n, p) is reaction cross-section maximum in three reactions, still3He
Abundance in natural isotope is very low, and only about 1.4 × 10-4%, obtains very difficult, price is sufficiently expensive.Therefore
Many experimental groups all start research and development new neutron detector to replace being based on3He neutron detector.
2nd, the method for nuclear recoil：When for E neutron and atomic nucleus elastic scattering occurs for projectile energy, the direction of motion of neutron changes
Become, energy has also been reduced, and the energy transmission of neutron reduction makes atomic nucleus be moved with certain speed to atomic nucleus, this atom
Core is known as " recoil nucleus ".Recoil nucleus is used as charged particle, it is easy to detect, recoil nucleus detectable signal and incident neutron intensity and energy
Amount is relevant.The method is mainly used to Used for Detecting Fast Neutrons, mainly uses the proton in rich hydrogenous material to recoil and is detected.
3rd, nuclear fission method：Neutron can fission with heavy nucleus effect, and fission method is exactly by recording heavy nuclear fission fragment
Method to detect neutron.For thermal neutron, slow neutron, always select235U、239Pu、233U does fissioner.
4th, activation method：When neutron and atom nuclear interaction, radiation capture is main mechanism.Neutron is easy to
Into one complex nucleus in excitation state of atomic nucleus formation, complex nucleus is returned by launching the rapid de excitation of one or several photons
To ground state.This capture neutron releases gamma-emitting process and is referred to as " radiation capture ", is represented with (n, γ).By measuring γ meters
Number, calculates neutron irradiation field intensity.
Current neutron detection method using it is more be neutron with3He and BF3Gas core reaction method.But also have with
Lower deficiency, the former due to3He gases obtain more difficult, therefore3He pipes are not only expensive, and monopolized at present by external product；
The latter is due to using gas, and density is relatively low, thus is difficult to make small size, and detection efficient is relatively low, while BF3It is a kind of poisonous
Material, manufacture craft requires special, and difficulty is increased, and the security to detection constitutes a threat to.
The content of the invention
The utility model supports the use to solve the above-mentioned deficiency of prior art there is provided a kind of new neutron pipe and with it
Preamplifier so that obtain that a kind of cost is low, be easy to make, the interference of anti-gamma-rays and long working life, working stability
The advantages of neutron tube and there is small volume, reliable operation, the preposition amplification that the signal shaping time is short, signal to noise ratio is high
Device.
Neutron tube technical scheme is as follows：A kind of neutron tube, including body 1, dead ring 2, anodic wire 3, upper end cover 4, insulation
Terminal 5, negative electrode 6, anode 7, boron carbide coating 8,
Body 1 is hollow cylindrical tube, and inwall scribbles the boron carbide coating 8 that thickness is 1 μm~6 μm, the body 1
One end is sealed using dead ring 2, and the other end is sealed using upper end cover 4, and the center of the upper end cover 4 is formed with insulated terminal
5, anode 7 is located on the insulated terminal 5 and insulated with upper end cover 4, and the outside of the upper end cover 4 is formed with negative electrode 6, and described
The outer wall and upper end cover 4 of negative electrode 6 and body 1 are conducted；
Anodic wire 3 is placed in inside body 1, and its one end is fixed on the dead ring 2, and the other end is fixed on insulated terminal 5 simultaneously
Conducted with the anode 7 welding；
Meanwhile, the cavity interior sealing of sealed body 1 has the magic different gas of 0.1~1 atmospheric pressure, and the magic different gas is
Ar gas and CH4The mixed gas of gas, wherein being 70%~95% according to volume ratio Ar gas.
Above-mentioned Ar gas and CH4The mixed gases matching and pressure of gas can reach that ionization signal is big and effect of signal stabilization
Really.Meanwhile, the thickness of boron carbide coating 8 is 1 μm~6 μm, to reach cross-section and ion transmission rate effect.Neutron tube
Size be based on actual inhomogeneity neutron field neutron flux measurement, suitable position sensitivity requirement is higher, detection area not bery
Big neutron field flux measurement, therefore the specific size of neutron tube in the technical program is determined according to actual conditions.
Above optimization technique index presses as follows to the importance ranking of influential effect：Apply boron thickness, mixed gas composition and
Proportioning and pressure, anodic wire diameter, internal diameter of tube body, it is described above reach that neutron detection efficiency is high, signal amplitude is larger, signal into
The shape time is short and other effects to refer to influence of the change of above technical indicator to neutron tube and signal detection performance.
It is preferred that, boron -10 is concentration boron in the boron carbide coating 8, and the isotopic content of boron -10 of the concentration boron is more than
90%.
It is preferred that, the thickness of the boron carbide coating 8 is 2 μm.
It is preferred that, the boron carbide coating 8 is replaced using boron oxide coatings.
It is preferred that, a diameter of 15 μm~50 μm of the anodic wire 3, to reach highfield effect near anodic wire.
It is preferred that, the internal diameter of the body 1 is 10mm~30mm, to reach electric-field intensity and mean free path purpose.
Technical scheme suitable for the preamplifier of the utility model neutron tube is as follows：
Preamplifier is charge amplifier, including charge amplifying circuit, pole-zero cancellation circuit, baseline restorer electricity
Road, schematic diagram is respectively referring to accompanying drawing 2,3,4, and preamplifier principle total figure is referring to accompanying drawing 9.
DC high-voltage power supply is supplied to neutron tube anodic wire through protective resistance R3, R6, and alternating component connects through resistance R3, electric capacity C1
Ground is filtered；It is grounded after neutron tube cathode connecting resistance R11.J1 inputs for high direct voltage, and J2 inputs for pulse signal, and J3 is low-pressure direct
Flow power input.J3 is separate standards power supply, and DC filtering is carried out through electric capacity C10, C11, C12, C13, C14 and inductance L1, L2,
Alternating component is filtered, is that active device carries out direct current supply.
The pulse signal drawn by neutron tube anodic wire sends into charge amplifier through capacitance C6, resistance R9.
The operational amplifier of charge amplifier (see accompanying drawing 2) is AD8065, by DC low voltage power supply through resistance R1, electric capacity C2
Powered with resistance R2, electric capacity C3 filter circuits, in-phase input end is grounded through resistance R22, and in-phase input end is by voltage-stabiliser tube D1 and electricity
R13 voltage stabilizings are hindered, pulse signal sends into inverting input through resistance R12；Output end signal is sent into anti-through feedback circuit Rf1 and Cf1
Phase input, the voltage signal exported through charge amplifier sends into pole-zero cancellation circuit.
The effect of charge amplifier is the output signal in order to which the amplified voltage signal that formed of the charge signal of input is exported
Send into pole-zero cancellation circuit.
Pole-zero cancellation circuit (see accompanying drawing 3) is grounded after rheostat VR1 and electric capacity C8 parallel connections through resistance R14, its input
Signal is sent into test point TP1 by connecting resistance R7, and it exports terminating resistor R8 and signal is sent into test point TP2, output signal feeding
Baseline restorer circuit.
Pole-zero cancellation electrical equipment be in order to which the limit for forming pulse signal is eliminated, so as to shorten the signal shaping time,
And reduce signal pile-up.
The operational amplifier of baseline restorer circuit (see accompanying drawing 4) is AD817A, by dc source through resistance R4, electric capacity C4 and
Powered after resistance R5, electric capacity C5 filtering, prime signal sends into in-phase input end through resistance R10；By rheostat VR2, resistance R16,
R17 and R23 carries out partial pressure feeding inverting input to feedback signal, passes through resistance R15, R21 and change rheostat VR2 current potential
To power supply partial pressure, change the base that rheostat VR2 current potential can make the anti-phase input terminal potential after regulating offset in-phase input end
Line drifts about, and electric capacity C7, C9 carry out ac filter to dc source.Signal is sent into test point P1 by output end.
Baseline restorer circuit is to be reverted to over the ground by power supply null offset or by the null offset that charge accumulation is caused
Zero-bit.
It is preferred that, JP1, JP2, JP3 are set to be additional, wherein, R18, R19, R20, R23 are partial pressure protective resistance, and JP3 is pre-
Setting is stayed, increase filtering is expanded or changes time constant；When wire jumper JP1, JP2 selection are 3,4, it is operated in charge-sensitive and puts
Under big device state；When wire jumper JP1, JP2 selection are 1,2, it is operated under pressure sensitive amplifier status.
It is preferred that, P2, P3, P4, P5 are reserved fixing hole, by resistance R24, R25, R26, R27 resistance eutral grounding, or are passed through
Capacity earth is to be tested by Electro Magnetic Compatibility.
It is preferred that, GND1 is reserved fixing hole, totally four, distribution assist side corner, with fixing circuit board, or by circuit
Plate is fixed on the neutron tube for adding slowing down layer.
The pulse signal drawn by neutron tube forms voltage pulse signal output after preamplifier, contains amplitude letter
Breath and temporal information.
Neutron tube of the present utility model is shown with preamplifier test：Signal amplitude is about 0.6V, and signal to noise ratio is about
200:1, maximum allowable counting rate is more than 2 × 106Individual/second, anti-γ interference performances are very strong.
Brief description of the drawings
Fig. 1 is a kind of structural representation of neutron tube.
As shown in figure 1,1 is body, 2 be dead ring, and 3 be anodic wire, and 4 be upper end cover, and 5 be insulated terminal, and 6 be negative electrode, 7
It is boron carbide coating for anode, 8.
Fig. 2 is charge amplifier schematic diagram；
Fig. 3 is pole-zero cancellation circuit theory diagrams；
Fig. 4 is baseline restorer circuit theory diagrams；
Fig. 5 is neutron tube plateau curve figure；
The neutron signal figure that Fig. 6 is measured when being high pressure 750V；
The γ signal graphs that Fig. 7 is measured when being high pressure 1600V；
Fig. 8 is neutron detection efficiency and boron carbide thickness relationship figure；
Fig. 9 is preamplifier principle total figure.
Embodiment
Embodiment 1
A kind of neutron tube, as shown in figure 1, including body 1, dead ring 2, anodic wire 3, upper end cover 4, insulated terminal 5, negative electrode
6th, anode 7, boron carbide coating 8,
Wherein, body 1 is Φ 24mm × 200mm 301 stainless steel tubes, wall thickness 2mm, and its inwall scribbles 0.6mg/
cm2The thick isotopic content of boron -10 is 95% boron carbide coating 8, equivalent to the boron carbide coating 8 that thickness is 2 μm；
Wherein, one end of the body 1 is sealed using dead ring 2, and the other end is sealed using upper end cover 4, and it is described on
The center of end cap 4 is formed with insulated terminal 5, and anode 7 is located on the insulated terminal 5, and negative electrode is formed with the outside of the upper end cover
6, and the outer wall and upper end cover 4 of the negative electrode 6 and body 1 conduct；Anodic wire 3 is gold-plated tungsten wire, a diameter of 25 μm, described
The dead ring 2 is fixed in the one end of anodic wire 3, the other end of the anodic wire 3 be fixed on insulated terminal 5 and with the anode 7
Welding is conducted；
The magic different gas of 0.3 atmospheric pressure, i.e. Ar gas and CH are filled with the cavity of sealed body 14The mixed gas of gas,
And Ar gas and CH4The volume ratio of gas is 9:1.
It is used for the preamplifier of the neutron tube in the example for charge amplifier, including charge amplifying circuit, pole
Zero cancellation circuit, baseline restorer circuit, principle is as shown in accompanying drawing 2,3,4, and preamplifier principle total figure is shown in accompanying drawing 9.
DC high-voltage power supply is supplied to neutron tube anodic wire through protective resistance R3, R6, and alternating component connects through resistance R3, electric capacity C1
Ground is filtered；It is grounded after neutron tube cathode connecting resistance R11.J1 inputs for high direct voltage, and J2 inputs for pulse signal, and J3 is low-pressure direct
Flow power input.J3 is separate standards power supply, and DC filtering is carried out through electric capacity C10, C11, C12, C13, C14 and inductance L1, L2,
Alternating component is filtered, is that active device carries out direct current supply.
The pulse signal drawn by neutron tube anodic wire sends into charge amplifier through capacitance C6, resistance R9.
The operational amplifier of charge amplifier (see accompanying drawing 2) is AD8065, by DC low voltage power supply through resistance R1, electric capacity C2
Powered with resistance R2, electric capacity C3 filter circuits, in-phase input end is grounded through resistance R22, and in-phase input end is by voltage-stabiliser tube D1 and electricity
R13 voltage stabilizings are hindered, pulse signal sends into inverting input through resistance R12；Output end signal is sent into anti-through feedback circuit Rf1 and Cf1
Phase input, the voltage signal exported through charge amplifier sends into pole-zero cancellation circuit.
The effect of charge amplifier is the output signal in order to which the amplified voltage signal that formed of the charge signal of input is exported
Send into pole-zero cancellation circuit.
Pole-zero cancellation circuit (see accompanying drawing 3) is grounded after rheostat VR1 and electric capacity C8 parallel connections through resistance R14, its input
Signal is sent into test point TP1 by connecting resistance R7, and it exports terminating resistor R8 and signal is sent into test point TP2, output signal feeding
Baseline restorer circuit.
Pole-zero cancellation electrical equipment be in order to which the limit for forming pulse signal is eliminated, so as to shorten the signal shaping time,
And reduce signal pile-up.
The operational amplifier of baseline restorer circuit (see accompanying drawing 4) is AD817A, by dc source through resistance R4, electric capacity C4 and
Powered after resistance R5, electric capacity C5 filtering, prime signal sends into in-phase input end through resistance R10；By rheostat VR2, resistance R16,
R17 and R23 carries out partial pressure feeding inverting input to feedback signal, passes through resistance R15, R21 and change rheostat VR2 current potential
To power supply partial pressure, change the base that rheostat VR2 current potential can make the anti-phase input terminal potential after regulating offset in-phase input end
Line drifts about, and electric capacity C7, C9 carry out ac filter to dc source.Signal is sent into test point P1 by output end.
Baseline restorer circuit is to be reverted to over the ground by power supply null offset or by the null offset that charge accumulation is caused
Zero-bit.
JP1, JP2, JP3 are set to be additional, wherein, R18, R19, R20, R23 are partial pressure protective resistance, and JP3 sets to be reserved
Put, expand increase filtering or change time constant；When wire jumper JP1, JP2 selection are 3,4, charge amplifier is operated in
Under state；When wire jumper JP1, JP2 selection are 1,2, it is operated under pressure sensitive amplifier status.
P2, P3, P4, P5 are reserved fixing hole, by resistance R24, R25, R26, R27 (0 Ω) resistance eutral grounding, or are passed through
Capacity earth is to be tested by Electro Magnetic Compatibility.
GND1 is reserved fixing hole, totally four, is distributed assist side corner, with fixing circuit board, or wiring board is consolidated
Due on the neutron tube for adding slowing down layer.
The pulse signal drawn by neutron tube forms voltage pulse signal output after preamplifier, contains amplitude letter
Breath and temporal information.
Boron carbide (10B isotope abundances more than 90%) coating optimum thickness determine, as shown in Figure 8.
The detection efficient of neutron when calculating different boron carbide thickness through theory, it can be found that applying thickness from accompanying drawing 8
Degree has a peak value in 1~8 μ m detection efficient, and maximum is located near 4 μm；Used due to currently there are no suitable technique
Make pure boron plating, but use its compound, such as boron oxide or boron carbide.Use boron carbide in this example, boron carbide thickness 2~
Detection efficient is higher in 6 μ ms, but during 8 relative thick of boron carbide coating, the ionizing power of charged particle is due to collision energy loss
And declined so that signal is difficult to distinguish.Therefore after secondary charged particle energy loss and detection efficient relation is considered, selection
The optimal thickness of boron carbide coating 8 is 2 μm, equivalent to 0.6mg/cm2, it is about 14% thus to calculate neutron detection efficiency.
Gas Amplification Multiple is realized.
Thermal neutron reacts through tube wall with the boron 10 in inside coating, produces7Li and α ions, from coating outgoing from
Son collides with working gas, ionizes out electronics-cation pair.Under electric field action, electronics is drifted around to anodic wire,
Cation drifts about to negative electrode tube wall；Electronics forms avalanche ionization under the several nm forceful electric power field actions in anodic wire surface, production
Raw more negative ions pair, so that initial ionization signal be amplified.Known anodic wire diameter b, ips a, gas pressure P
(KPa), gas property (Δ V) and added negative and positive pole tension V, can be calculated by below equation and obtain Gas Amplification Multiple M：
25 μm of gold-plated tungsten wire, neutron bore is 20mm, the Ar gas and CH of 0.3 atmospheric pressure4The mixed gas of gas, its
Middle Ar gas accounts for 90% and CH4Gas accounts for 10% (Δ V=2.28), then can calculate Gas Amplification Multiple M in high pressure 850V
For 1694；Actual anode filament voltage operating point is selected after being measured by plateau curve, and general selection plateau curve plateau slope is smaller, times magnification
The voltage range medium position that number is relatively stablized.
The signal of charge amplifier is realized.
Calculating obtains charge amplifier output signal and the relation of input signal isTime is normal
Number, with Rf1=10K Ω, it is 10 volts/skin coulomb that Cf1=10pf, which is calculated and obtained conversion gain,.
Pole-zero cancellation is realized.
By adjusting VR2 so that the signal undershoot that charge amplifier is sent is eliminated, after pole-zero cancellation circuit network
Output signal is：
Wherein
It can be seen that, its output amplitude is constant, and time constant is by as long as reducing time constant changes τ2, the rise time one
As be nanosecond order, therefore R14 is set to 100k Ω.
Neutron tube plateau curve is measured.
The plateau curve of neutron tube is measured in Am-Be Neutron Radiation Fields using the preamplifier of making.Use GW1016
Intelligent calibration device carries out count measurement to it, and setting discriminating threshold is 0.2V, and gate time is 30s, and acquisition counter, obtained level ground is bent
Line as shown in Figure 5, so that it is determined that the anodic wire operating voltage of the detector be 750V.
Neutron tube is in use, neutron tube and preamplifier are inserted in neutron measurement together, and shielding is implemented in outside.Will
High direct voltage is slowly raised to quiescent potential and is added to neutron tube, and low-voltage dc power supply is powered for preamplifier.Arteries and veins will be exported
Rush signal input scaler and carry out neutron counting or counting rate measurement；If sending single-channel pulse after output signal is screened through discriminator
Amplitude analyzer, and connection server, can also carry out data record.
The measurement of neutron detection signal.
As shown in Figure 6, the neutron signal amplitude of detection is more than 600mV to neutron detection signal, and the rise time is less than
100ns, the burst length is less than 500ns, is 2 × 10 with that can calculate its maximum count rate according to pulse width6, signal to noise ratio is about
200:1。
Anti- γ interference performances.
As shown in Figure 7, high pressure is added to the γ signal amplitudes about 100mV measured during 1600V to γ signal measurements,
Below 1200V does not detect stable γ signals.
Therefore, discriminating threshold is set into 200mV to be just enough to fall γ signal screenings.
Preferred embodiment of the present utility model described in detail above, still, the utility model is not limited to above-mentioned reality
The detail in mode is applied, in range of the technology design of the present utility model, the technical solution of the utility model can be entered
The a variety of equivalents of row, these equivalents belong to protection domain of the present utility model.
It is further to note that each particular technique feature described in above-mentioned embodiment, in not lance
In the case of shield, it can be combined by any suitable means.
In order to avoid unnecessary repetition, the utility model no longer separately illustrates to various possible combinations.
Claims (6)
1. a kind of neutron tube, it is characterised in that including body, dead ring, anodic wire, upper end cover, insulated terminal, negative electrode, anode,
Boron carbide coating,
Body is hollow cylindrical tube, and inwall scribbles the boron carbide coating that thickness is 1 μm~6 μm, and one end of the body makes
Sealed with dead ring, the other end is sealed using upper end cover, and the center of the upper end cover is formed with insulated terminal, and anode is located at
Insulated on the insulated terminal and with upper end cover, be formed with negative electrode on the outside of the upper end cover, and the negative electrode and body is outer
Wall and upper end cover are conducted；
Anodic wire is placed in tubular body, and its one end is fixed on the dead ring, the other end be fixed on insulated terminal and with the sun
Pole welding is conducted；
Meanwhile, the cavity interior sealing of sealed body 1 has the magic different gas of 0.1~1 atmospheric pressure, and the magic different gas is Ar gas
And CH4The mixed gas of gas, wherein being 70%~95% according to volume ratio Ar gas.
2. a kind of neutron tube according to claim 1, it is characterised in that boron -10 is concentration boron in the boron carbide coating 8,
The isotopic content of boron -10 of the concentration boron is more than 90%.
3. a kind of neutron tube according to claim 2, it is characterised in that the thickness of the boron carbide coating is 2 μm.
4. a kind of neutron tube according to any claim 1~3, it is characterised in that the boron carbide in the boron carbide coating
Replaced using boron oxide.
5. a kind of neutron tube according to claim 4, it is characterised in that a diameter of 15 μm~50 μm of the anodic wire.
6. a kind of neutron tube according to claim 5, it is characterised in that the internal diameter of the body is 10mm~30mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621358246.7U CN206515476U (en) | 2016-12-12 | 2016-12-12 | A kind of neutron tube |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201621358246.7U CN206515476U (en) | 2016-12-12 | 2016-12-12 | A kind of neutron tube |
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| CN206515476U true CN206515476U (en) | 2017-09-22 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680863A (en) * | 2016-12-12 | 2017-05-17 | 烟台大学 | Neutron tube |
| RU2743849C1 (en) * | 2020-04-23 | 2021-02-26 | Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" (Госкорпорация "Росатом") | Ionisation fission chamber for detecting fast neutrons |
-
2016
- 2016-12-12 CN CN201621358246.7U patent/CN206515476U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106680863A (en) * | 2016-12-12 | 2017-05-17 | 烟台大学 | Neutron tube |
| RU2743849C1 (en) * | 2020-04-23 | 2021-02-26 | Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" (Госкорпорация "Росатом") | Ionisation fission chamber for detecting fast neutrons |
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