CN101569848B - Real-time precious gas polarization generator and delivery box of polarized precious gas - Google Patents

Abstract

A real-time noble gas polarization generator comprises a cavity, a heat preservation unit, a base bottle, a heating source and an excitation unit, wherein the cavity is provided with an upper cover and a lower cover which are composed of high-permeability substances, and a first magnet unit and a second magnet unit which have the same magnetic field direction and are used for generating a magnetic field; the heat preservation unit is positioned in the cavity and is provided with a furnace space for keeping the temperature within a preset range; the base bottle is positioned in the space of the furnace body and is used for filling noble gas; the heating source is used for providing heat to the furnace body space so as to maintain the temperature of the base bottle within a preset range; the exciting unit is used for generating a polarized laser beam with a specific wavelength and the same direction as the magnetic field direction of the magnetic field space to pass through the base bottle so as to polarize the noble gas in the base bottle.

Description

Real-time precious gas polarization generator and delivery box of polarized precious gas

technical field

The invention relates to a noble gas polarization generator, specifically, a real-time (InSitu) noble gas polarization generator. the

Background technique

Polarized noble gases (polarized noble gases) have been widely used in physical experiments, neutron beam research, material science, and medical applications. The hydrogen 1 ( ¹ H) polarization signal of traditional polarization is more than 10,000 times, which makes a new field of medical and material science applications appear that cannot be achieved before. In terms of research on neutron beams, polarized helium 3 ( ³ He) gas can filter neutrons very effectively to achieve the purpose of polarizing neutrons without limiting the energy and momentum of neutron beams.

Polarized noble gases can be prepared by optically excited nuclear spin exchange (SEOP). For example, the optically excited nuclear spin exchange method of helium 3 includes that the covalent electrons of rubidium are optically excited to a single ground state spin state to form polarization, and the polarized rubidium covalent electrons collide with helium 3 atoms to generate spin Bias transfer. 1 is a schematic diagram of a known noble gas polarization generator 100 using optically excited nuclear spin exchange method, which includes a group of Helmholtz (Helmholtz) coils 110 and 111 with a diameter of about 1 meter. The furnace 112 is located between the Helmholtz coils 110 and 111, the base bottle 114 is located in the holding furnace 112, and filled with rubidium 120, helium 3, helium 4 and nitrogen, and a heating and temperature control unit 118 is connected via a heat transfer path 128 The holding furnace 112 is used to control the temperature of the base bottle 114, so that rubidium 120 evaporates into a gaseous state, and a laser 124 with a wavelength of 794.7nm and a power of 30W generates a laser beam 130 and passes through a polarizing device 126 to generate a circularly polarized laser beam 132, which passes through the base bottle 114 Stopping at the laser stop unit 122 , and an NMR coil 116 is located near the vial 114 to send and receive radio frequency (RF) signals to detect the polarization of He3 in the vial 114 . The Helmholtz coils 110 and 111 are used to pass a large current (about 8 amperes) to generate a magnetic field, and the distribution of the magnetic force lines is shown in Figure 2, which is a Helmholtz coil of a known noble gas polarization generator In the distribution diagram of the magnetic field lines, a uniform magnetic field space is formed at the central position 134, and the intensity of the magnetic field B ₀ is about 25.6 Gauss (Gauss).

且 $m_j=+\frac{1}{2}$ 的激态，之后铷120的电子衰退到 $m_j=-\frac{1}{2}$ 与 $m_j=+\frac{1}{2}$ 的基态( 

)，然而任何回到 

且 $m_j=-\frac{1}{2}$ 的电子会被圆偏极激光光束132重新激化，最后铷120的电子都被激化到  $m_j=+\frac{1}{2}$ 的基态( 

)，产生偏极化的铷，此过程典型上需花费数毫秒的时间。在铷-氦3的自旋交换与氦的超偏极化的过程中，通过超精细费米接触的交互作用，氦3的原子核与偏极化铷的电子自旋交互作用以转移偏极化铷的自旋状态到氦3上，使氦3产生超偏极化，此过程需要铷电子的波函数与氦3的原子核紧密重迭，且交互作用随原子间的距离以指数般的变化，因此只有少部分的碰撞产生足够地重迭导致铷与氦3的自旋交换，相对于铷120在基瓶114中偏极化稳态的达成约需数毫秒，氦3偏极化的发生需要小时这样的数量级，因此，氦3的光学激化核自旋交换法偏好使用加热的基瓶114，以增加偏极化铷的密度，进而增加铷-氦3自旋交换的机率。  Referring to Fig. 1, in the process of optical excitation of Rubidium 120, since the 794.7nm circularly polarized laser beam 132 is equivalent to the D1 transition line of Rubidium 120, and the circularly polarized light can only drive the spin state of electrons from $m_j=-\frac{1}{2}$ arrive $m_j=+\frac{1}{2}$ transition, so the laser beam 132 drives the electrons of the rubidium 120 from and $m_j=-\frac{1}{2}$ ground state transition to

and $m_j=+\frac{1}{2}$ excited state, after which the electrons of Rubidium 120 decay to $m_j=-\frac{1}{2}$ and $m_j=+\frac{1}{2}$ ground state (

), however any returns

and $m_j=-\frac{1}{2}$ The electrons of the rubidium 120 will be re-excited by the circularly polarized laser beam 132, and finally the electrons of the rubidium 120 will be excited to $m_j=+\frac{1}{2}$ ground state (

), producing polarized rubidium, which typically takes a few milliseconds. During the spin exchange of rubidium-helium 3 and the hyperpolarization of helium, through the interaction of hyperfine Fermi contacts, the nucleus of helium 3 interacts with the electron spin of polarized rubidium to transfer the polarization The spin state of rubidium is transferred to helium 3, which makes helium 3 hyperpolarized. This process requires the wave function of rubidium electrons to overlap closely with the nucleus of helium 3, and the interaction changes exponentially with the distance between atoms. Therefore, only a small number of collisions produce enough overlap to cause the spin exchange of rubidium and helium 3. Compared with the realization of the polarization steady state of rubidium 120 in the base bottle 114, which takes about several milliseconds, the occurrence of helium 3 polarization requires Therefore, the optically excited nuclear spin exchange method of helium 3 prefers to use a heated base bottle 114 to increase the density of polarized rubidium, thereby increasing the probability of rubidium-helium 3 spin exchange.

Fig. 3 is the schematic diagram that detects the polarization of helium 3 with nuclear magnetic resonance coil, detects the polarization of helium 3 in base bottle 114 with described nuclear magnetic resonance coil 116, and nuclear magnetic resonance coil 116 is located in uniform magnetic field B ₀ , is an independent pulse A type of NMR system, which includes transmitting and receiving coils 210 and 220 respectively located at two ends of the base bottle 114 . Transmitting and receiving coils 210 and 220 transmit RF signals with the same frequency as the helium 3 in the magnetic field B ₀ precession (regression) frequency to make the helium 3 reach a small angle of inclination, and receive the returned RF signal to detect the helium 3 in the base bottle 114 of polarization. Since the precession frequency of Helium 3 in the magnetic field B ₀ is proportional to the magnitude of the magnetic field B ₀ , the unstable magnetic field will affect the detection results. In addition, the interaction between polarized He3 and the inhomogeneous magnetic field is one of the main reasons for the depolarization of He3, so the inhomogeneous magnetic field leads to the storage time or relaxation time of He3 after polarization. ) T1 decreases, accelerating the decay of polarized helium 3 .

Since the process of helium 3 polarization requires a magnetic field B ₀ , the energy levels of rubidium atoms are split and the polarized rubidium and polarized helium-3 follow directions. In addition, helium 3 must be placed in a uniform The depolarization of helium-3 is avoided in the magnetic field, and the polarized detection of helium-3 requires a stable magnetic field. Therefore, a stable and uniform magnetic field space is very important for polarizing the noble gas.

However, as shown in FIG. 1, a known noble gas polarization generator 100 generates a uniformity (( Maximum value - minimum value)/average value) is less than 10 ^-4 in a stable and uniform magnetic field space, so a stable power supply and ambient temperature control are required to avoid affecting the stability of the magnetic field due to changes in current or temperature. The equipment cost and the manufacturing cost of polarized helium 3 are relatively high. In addition, since the magnetic fields generated by the Helmholtz coils 110 and 111 will be affected by surrounding electrical products, electromagnetic fields and ferromagnetic substances, it is difficult to generate a uniform magnetic field in an open system. And 111 peripheral with metal shielding to avoid electromagnetic interference from the external environment. However, the Helmholtz coils 110 and 111 and the metal shielding are bulky and heavy, and are not suitable for moving. Therefore, traditionally, if the polarized helium 3 gas is to be transported to the place of use, the base bottle 114 needs to be removed from the The Helmholtz coils 110 and 111 are taken out, put into a transfer box (such as a solenoid box or a permanent magnet box) with a uniform magnetic field and a shielding effect, and then transported. Referring to Fig. 1 and Fig. 2, Fig. 2 is a distribution diagram of the Helmholtz coil magnetic field lines of a known noble gas polarization generator, when the base bottle 114 is taken out from the Helmholtz coils 110 and 111, it will After the inhomogeneous magnetic field A or B, the polarization of helium 3 is affected. Even if the magnetic fields generated by the Helmholtz coils 110 and 111 are turned off to eliminate the inhomogeneous magnetic fields A and B, only the earth's magnetic field is left at this time, and the earth's magnetic field is too small, and the polarized helium 3 is susceptible to external electromagnetic interference, causing Attenuation of He-3 polarization.

This method of first polarizing the precious gas and then transporting it for use is a non-real-time application. In addition to the problem of signal loss after the polarized precious gas is taken out, which causes troubles in transportation, there is also a limit on the use time (subject to limited to delay time), if the precious gas can be biased and used simultaneously, it can solve the problem of transportation and the limitation of use time at the same time. Generally, this kind of equipment that can be manufactured and used on the spot is called real-time (InSitu) equipment. the

Therefore, there are above-mentioned inconveniences and problems in the known methods for non-real-time precious gas polarization re-transportation. the

Contents of the invention

The object of the present invention is to propose a real-time precious gas polarization generator with small volume and magnetic field shielding. the

Another object of the present invention is to provide a real-time precious gas polarization generator that is easy to transport. the

Another object of the present invention is to provide a portable real-time precious gas polarization generator. the

Another object of the present invention is to provide a real-time precious gas polarization generator with reduced cost. the

For realizing the above object, technical solution of the present invention is:

A real-time precious gas polarization generator, comprising a cavity, a heat preservation unit, a base bottle, a heating source and an excitation unit, characterized in that:

The cavity has an upper cover and a lower cover made of a material with high magnetic permeability, and first and second magnet units with the same magnetic field direction to generate a magnetic field, and the first and second magnet units are respectively connected to the On both sides of the upper cover and the lower cover, the upper cover and the lower cover are equidistant from the central part of the cavity so as to guide the magnetic field to generate a uniform magnetic field space inside the cavity , and form a shielding effect;

The heat preservation unit is located in the cavity and has a furnace space to keep the temperature within a predetermined range;

The base bottle is located in the space of the furnace body and is used for filling precious gas;

The heating source is used to provide heat to the furnace space to maintain the temperature of the base bottle within the predetermined range;

The excitation unit is used to generate a polarized laser beam with a specific wavelength and the same direction as the magnetic field in the magnetic field space to pass through the base bottle to polarize the noble gas in the base bottle.

The aforementioned real-time noble gas polarization generator, wherein the polarized laser beam includes a circularly polarized laser beam. the

The aforementioned real-time noble gas polarization generator, wherein the upper cover has first and second extended side covers, the lower cover has third and fourth extended side covers, and the first magnet unit is located at the second Between the first and third extension side covers, and the second magnet unit is located between the second and fourth extension side covers. the

The aforementioned real-time precious gas polarization generator, wherein the first and second magnet units include:

a first permanent magnet;

a second permanent magnet;

A side wall, the side wall is made of the high magnetic permeability material, and is located between the first and second permanent magnets, so as to connect the first and second permanent magnets in series;

In the aforementioned real-time noble gas polarization generator, wherein the side wall has first and second extended side covers respectively engaging with the first and second permanent magnets. the

The aforementioned real-time noble gas polarization generator, wherein the high magnetic permeability material includes nickel-iron alloy. the

The aforementioned real-time precious gas polarization generator, wherein the heat preservation unit is made of glass, calcium silicate board or materials with heat preservation effect. the

In the aforementioned real-time noble gas polarization generator, the heating source includes a quartz tube connected to a heating gun or a pipeline or device that can provide constant hot air or hot material. the

The aforementioned real-time precious gas polarization generator, wherein the excitation unit includes:

A laser, located outside the cavity, for generating a laser beam;

A reflection unit, located in the cavity, used to reflect the laser beam, so that the laser beam passes through the base bottle;

A polarizing unit is located between the laser and the base bottle to polarize the laser beam. the

The aforementioned real-time noble gas polarization generator, wherein the reflection unit includes a reflection mirror or a prism. the

The aforementioned real-time precious gas polarization generator, wherein the excitation unit includes:

A laser, located outside the cavity, for generating a laser beam;

A reflection unit, located in the cavity, is used to reflect and polarize the laser beam, and make the laser beam pass through the base bottle. the

The aforementioned real-time noble gas polarization generator further includes a heat insulating layer located between the cavity and the heat preservation unit. the

The aforementioned real-time noble gas polarization generator, wherein the thermal insulation layer includes a heat transfer device. the

The aforementioned real-time noble gas polarization generator, wherein the heat transfer device includes a glass tube through which temperature-controlled gas passes. the

The aforementioned real-time noble gas polarization generator further includes a thermal insulation pad located between the thermal insulation layer and the thermal insulation unit. the

The aforementioned real-time noble gas polarization generator further includes a nuclear magnetic resonance coil located near the base bottle for transmitting and receiving radio frequency signals to detect the polarization degree of the noble gas. the

A transmission box for polarized noble gas, including a cavity and a base bottle, characterized in that:

The cavity has an upper cover and a lower cover made of a material with high magnetic permeability, and first and second magnet units with the same magnetic field direction to generate a magnetic field, and the first and second magnet units are respectively connected to the On both sides of the upper cover and the lower cover, the upper cover and the lower cover are equidistant from the central part of the cavity so as to guide the magnetic field to generate a uniform magnetic field space inside the cavity , and form a shielding effect;

The base bottle is located in the cavity and has polarized noble gas inside. the

In the aforementioned transfer box for polarized noble gas, the upper cover has first and second extended side covers, the lower cover has third and fourth extended side covers, and the first magnet unit is located at the second Between the first and third extension side covers, and the second magnet unit is located between the second and fourth extension side covers. the

The aforementioned transfer box for polarized noble gas, wherein the first and second magnet units include:

a first permanent magnet;

a second permanent magnet;

A side wall, the side wall is made of the high magnetic permeability material, and is located between the first and second permanent magnets, so as to connect the first and second permanent magnets in series;

In the aforementioned transfer box for polarized noble gas, wherein the side wall has first and second extended side covers respectively engaging with the first and second permanent magnets. the

In the aforementioned transfer box for polarized noble gas, the high magnetic permeability material includes nickel-iron alloy. the

The aforementioned transfer box for polarized noble gas further includes an anti-collision device located between the cavity and the base bottle. the

The aforementioned transfer box for the polarized noble gas further includes a nuclear magnetic resonance coil located near the base bottle for transmitting and receiving radio frequency signals to detect the degree of polarization of the polarized noble gas. the

After adopting the above technical scheme, the real-time precious gas polarization generator and the transmission box of the polarized precious gas of the present invention have the following advantages:

1. Significantly reduce the volume and weight of the precious gas polarization generator, making the precious gas polarization generator a portable device, which can generate polarized precious gas in real time when polarized precious gas is required. the

2. The cavity is directly used as the transfer box to avoid the attenuation of the polarization of the polarized precious gas due to an uneven magnetic field or external interference, thereby increasing the safety of transportation. the

Description of drawings

Fig. 1 is the schematic diagram of known precious gas polarization generator;

Fig. 2 is the distribution figure of the Helmholtz coil magnetic field line of known noble gas polarization generator;

Fig. 3 is the schematic diagram that detects helium 3 polarization with nuclear magnetic resonance coil;

Fig. 4 is the schematic diagram of the real-time precious gas polarization generator of the present invention;

Fig. 5 is the side view of the real-time precious gas polarization generator of the present invention;

Fig. 6 is the schematic diagram of the cavity in the real-time precious gas polarization generator of the present invention;

Fig. 7 is the front view of the cavity in the real-time precious gas polarization generator of the present invention;

Figure 8 is a distribution diagram of the horizontal magnetic field in the cavity;

Fig. 9 is the detection figure of the relaxation phenomenon that the polarized helium 3 base bottle is put into the cavity of the present invention;

Fig. 10 is the detection diagram of the relaxation phenomenon when the polarized helium 3 base bottle is placed in the known peripheral Helmholtz coil without metal shielding;

Figure 11 is a free induction decay signal diagram of polarized helium 3 before delivery;

Fig. 12 is a diagram of the free induction decay signal of polarized helium 3 after transport. the

Detailed ways

The present invention will be further described below in conjunction with embodiment and accompanying drawing. the

λ波板)或由分光镜与 

λ波板组成的圆偏极装置，以产生圆偏极激光光束进入基瓶328偏极其中的碱金属。在另一实施例中，激化单元包括激光336以及具有偏极激光光束334功能的反射单元322，因而省略偏极装置338。  Referring now to Fig. 4 and Fig. 5, Fig. 4 is a schematic diagram of the real-time noble gas polarization generator of the present invention, and Fig. 5 is a side view of the real-time noble gas polarization generator of the present invention, as shown in the figure, the The real-time precious gas polarization generator 300 includes a cavity 310, which has a uniform magnetic field space, and the cavity 310 forms a shielding effect on the magnetic field space, and a heat preservation unit (such as a heat preservation furnace) 324 is located in the cavity In the body 310, it has a furnace body space 325 to keep the temperature within a predetermined range, a heat insulating layer 320 is located between the cavity 310 and the heat preservation unit 324, a base bottle 328 is located in the furnace body space 325, and the base bottle 328 is filled with precious gas (such as helium 3 or xenon 129), alkali metal (such as rubidium) and buffer gas (such as nitrogen), and a heating source 332 is connected to the furnace body space 325 to maintain the temperature of the base bottle 328 in the predetermined range Inside, the alkali metal in the base bottle 328 is evaporated into a gaseous state, a thermal insulation pad 330 is located between the thermal insulation layer 320 and the heat preservation unit 324 to further block the transmission of heat, a laser 336 provides a laser beam 334, and a reflection unit ( For example reflective mirror or prism) 322 is positioned in cavity 310, for example the top of heat preservation unit 324, in order to reflect laser beam 334 to form the same laser path with the magnetic field direction of described magnetic field space to pass base bottle 328, a polarizing device 338 On the laser path between the laser 336 and the base bottle 328, for example, in front of the laser 336 or between the reflection unit 322 and the base bottle 328, the laser beam 334 is polarized so that the laser beam entering the base bottle 328 is polarized. The polarized laser beam is used to polarize the alkali metal in the base bottle 328, for example, to excite the covalent electrons of the alkali metal to the spin state of a single ground state, and the polarized alkali metal covalent electrons collide with the nuclei of the noble gas atoms to generate The transfer of spin polarization forms polarized noble gas, and a nuclear magnetic resonance coil 326 is located near the base bottle 328 for transmitting and receiving RF signals to detect the polarization of the noble gas in the base bottle 328 . In this embodiment, the laser 336, the reflective unit 322 and the polarizing device 338 form an excitation unit, which is used to generate a polarized laser beam with a specific wavelength and the same direction as the magnetic field in the magnetic field space. The precious gas in the bottle 328, the heat preservation unit 324 is made of glass, calcium silicate plate or any material with heat preservation effect, to keep the temperature of the furnace body space 325 within the predetermined range, the heating source 332 includes a constant hot blast or Hot material heats the pipeline or device of base bottle 328, such as a quartz tube connected to the heating air gun, and the heat insulating layer 320 is made of heat insulating material or heat transfer device that can take heat away, such as surrounding on the cavity 310 inner wall The glass tube and the temperature-controlled gas pass through the glass tube to effectively take away the heat dissipated to form a uniform temperature distribution, so as to avoid the deterioration of the uniformity of the magnetic field space inside the cavity 310 due to the uneven temperature distribution, which affects Polarization efficiency. In various embodiments, the polarizing means 338 in the excitation unit comprises a polarizing plate (e.g.

λ wave plate) or by beam splitter and

A circular polarizing device composed of a λ wave plate is used to generate a circularly polarized laser beam and enter the base bottle 328 to polarize the alkali metal therein. In another embodiment, the excitation unit includes a laser 336 and a reflection unit 322 functioning as a polarized laser beam 334 , thus omitting the polarizing device 338 .

In an embodiment of the present invention, the reflection unit 322, the heat insulation layer 320 and the heat insulation pad 330 are detachable, and after the noble gas is polarized, the reflection unit 322, the heat insulation layer 320 and the heat insulation pad 330 are removed, And add elastic anti-collision devices (such as foam of appropriate shape and size) to place between the base bottle 328, the heat preservation unit 324 and the cavity 310, to fix the base bottle 328 to avoid collisions, and use the cavity 310 as a transport box , to transport the polarized precious gas to where it is needed. In another embodiment of the present invention, the reflection unit 322, the heat preservation unit 324, the heat insulation layer 320 and the heat insulation pad 330 are removed, the base bottle 328 is kept in the cavity 310, and a flexible anti-collision device (such as a suitable The shape and size of the foam) is placed between the base bottle 328 and the cavity 310 to fix the base bottle 328 to avoid collisions, and the cavity 310 is used as a transport case. In yet another embodiment of the present invention, the reflection unit 322 and the heat insulation pad 330 are removed, and an elastic anti-collision device (such as foam of appropriate shape and size) is installed on the base bottle 328, the heat preservation unit 324 and the heat insulation layer. 320 (such as heat insulating material), avoid collision with fixed base bottle 328, and use cavity 310 as transport case. Since the cavity 310 has a uniform magnetic field and a shielding effect, the polarized noble gas will not be affected by an uneven magnetic field or external electromagnetic interference during transportation, which will cause attenuation of the polarized noble gas. the

In different embodiments of the present invention, the real-time precious gas polarization generator 300 has a small weight (for example, less than ten kilograms) and a miniaturized volume, and can be transported to occasions that require polarized precious gas to generate polarization in real time. liquefied noble gases. The miniaturized precious gas polarization generator becomes a portable device, increasing flexibility and convenience in use. In addition, under the condition that the use space is limited, the noble gas can be continuously polarized in real time without taking out the base bottle 328 , and the problem of being limited by the relaxation time T1 of the polarized noble gas is avoided. For example, in the related research of neutron beams, when the polarized noble gas is used as the spin filter, the relaxation time T1 determines the applicable time of the spin filter. By continuously polarizing the noble gas in real time, the The research of the neutron beam will not be suspended because the relaxation time T1 has been reached, which has excellent operability. the

Referring now to Fig. 6 and Fig. 7, Fig. 6 is a schematic diagram of the chamber in the real-time noble gas polarization generator of the present invention, and Fig. 7 is a front view of the chamber in the real-time noble gas polarization generator of the present invention As shown in the figure, in one embodiment, the cavity 310 includes an upper cover 342 and a lower cover 344 made of high magnetic permeability material (μ-metal), such as nickel-iron alloy, the two are opposite to the cavity 310 The central part is equidistant, for example has the same size, and the magnet units 370 and 372 are respectively connected between the two sides of the upper cover 342 and the lower cover 344, as a magnetic source for generating a magnetic field, the magnet unit 370 includes a permanent magnet 316 and 318, and a side wall 348 between the permanent magnets 316 and 318, in order to connect the permanent magnets 316 and 318 in series, the magnet unit 372 includes the permanent magnets 312 and 314, and a side wall between the permanent magnets 312 and 314 The wall 346 is used for connecting the permanent magnets 312 and 314 in series. The magnetic field directions of the magnet units 370 and 372 are the same, for example, the N-pole directions 374 of the permanent magnets 312-318 are all upward, and the side walls 346 and 348 are made of high magnetic permeability materials. Preferably side wall 348 has extended side covers 358 and 360 respectively engaging permanent magnets 316 and 318 to connect them in series, and side wall 346 has extended side covers 354 and 356 respectively engaging permanent magnets 312 and 314 to connect them in series Together, the upper cover 342 has extension side covers 350 and 352, the lower cover 344 has extension side covers 362 and 364, the magnet unit 370 is located between the extension side covers 352 and 364, and the magnet unit 372 is located between the extension side covers 350 and 362 . The magnetic field lines of the permanent magnets 312-318 are guided by the side walls 346 and 348, the upper cover 342 and the lower cover 344, forming a uniform magnetic field space in which the magnetic field direction is the up-down direction (downward in this embodiment) inside the cavity 310, and its horizontal The distribution of the magnetic field is shown in Figure 8, which shows that there is a uniform magnetic field B ₀ ' between the horizontal distance of 8 cm and 28 cm in the cavity 310, and its magnetic field size is about 1.2E-3 Tesla (Tesla), and The uniformity of the magnetic field between the horizontal distance of 13 cm and 23 cm is less than 10 ^-4 , which has met the requirements of the magnetic field uniformity required for the polarization of the noble gas, so it can be used to provide the stability required for the polarization of the noble gas uniform magnetic field. In addition, since the cavity 310 is made of a material with high magnetic permeability, a shielding effect is automatically formed. In one embodiment, the strength of the uniform magnetic field B ₀ ′ is adjusted to be 10 Gauss, which is consistent with the magnitude of a standard guide field for maintaining neutron polarization. In another embodiment, the permanent magnets 312-318 and the bonding areas 350-364 are bonded together via adhesives, or bonded together via mechanical structures such as screws or clamps. In different embodiments, the required magnetic field space can be generated by adjusting the number of side walls and permanent magnets in the magnet units 370 and 372. For example, the magnet units 370 and 372 can each be a single permanent magnet directly connected to the upper cover 342 and The lower cover 344 , or more than two permanent magnets are connected in series via a plurality of side walls, and then connected with the upper cover 342 and the lower cover 344 .

Now referring to FIG. 5, it is illustrated by taking the generation of polarized helium 3 as an example, wherein, as shown in FIG. Shield to block outside interference. The base bottle 328 is filled with rubidium, helium-3, helium-4 and nitrogen, and the reflection unit 322 is a reflection mirror. The heat is supplied to the furnace body space 325 via the heating source 332 to maintain the temperature of the base bottle 328, and the rubidium is evaporated into a gaseous state, and the laser beam 336 generates a laser beam 334 with a wavelength of 794.7nm and provides a polarized wavelength of 794.7nm after passing through the polarizing device 338. The laser beam passes through the reflection unit 322 to form a laser path in the same direction as the magnetic field B ₀ ′, passes through the base bottle 328, and excites the rubidium to a single ground spin state, and the collision of the nucleus of the helium 3 with the rubidium produces a spin offset transfer, Polarized helium 3 is formed. Since the cavity 310 forms a uniform magnetic field through permanent magnets and high-permeability materials, it does not require a stable power supply to provide a large current to generate a uniform magnetic field. In addition to greatly reducing the volume and weight of the precious gas polarization generator 300 , to more effectively reduce the equipment cost and the manufacturing cost of polarized helium 3 .

Please refer to Fig. 9 and Fig. 10 again, Fig. 9 is that the helium 3 base bottle after the polarization is put into the relaxation phenomenon detection figure in the cavity of the present invention, Fig. 10 is that the helium 3 base bottle after the polarization is put into known The relaxation phenomenon detection diagram in the Helmholtz coil without metal shielding on the periphery, they are respectively under the pressure of 1 atmosphere, the polarized helium 3 base bottle is put into the cavity of the present invention and the known non-metal shielding on the periphery Diagram of detection of relaxation phenomena in a Helmholtz coil. Taking a base bottle with a diameter of 5 cm and a height of 6 cm as an example, the relaxation detection results of placing polarized helium 3 in the cavity with a uniform magnetic field of the present invention are shown in Figure 9, and the relaxation time T1 is about 24.75 hours. And place the helium after the polarization 3 in the magnetic field that the Helmholtz coil of the conventional periphery produces without metal shielding and relax detection result as shown in Figure 10, and its relaxation time T1 is about 17.5 hours, shows the present invention Can provide better protection to slow down the decay of polarized He-3. the

Please refer to Fig. 11 and Fig. 12 at last, Fig. 11 is the free induction decay (Free Induction Decay; FID) signal figure of polarized helium 3 before transporting, Fig. 12 is polarized helium 3 after transporting (for example according to the present invention The free induction decay signal diagram of the cavity as a transport box, which is transported by car from the laboratory to the office several kilometers away), as shown in the figure, the FID signal of the polarized helium 3 before and after transport The peak value of the FID signal hardly changes, which shows that after the polarized helium 3 is formed, the cavity of the present invention is directly used as a delivery box to transport the polarized helium 3 to the place of use, such as a neutron furnace or a hospital, etc. Problems such as signal loss after the polarized helium 3 is taken out from the polarized device. the

The above embodiments are only for illustrating the present invention, rather than limiting the present invention. Those skilled in the relevant technical field can also make various transformations or changes without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also belong to the category of the present invention and should be defined by each claim. the

Description of component symbols

100 precious gas polarization generator

110-111 Helmholtz coil

112 holding furnace

114 base bottle

116 MRI coils

118 Heating and temperature control unit

120 rubidium

122 laser stop unit

124 laser

126 polarizing device

128 heat transfer path

130 laser beams

132 circularly polarized laser beams

134 center position

210 Transmitting and receiving coils

220 Transmitting and receiving coils

300 real-time precious gas polarization generator

310 cavity

312-318 permanent magnet

320 insulation layer

322 reflection unit

324 insulation unit

325 furnace body space

326 MRI coil

328 base bottle

330 heat insulation pad

332 heating source

334 laser beam

336 laser

338 Polarization device

342 cover

344 lower cover

346-348 side wall

350-364 joint area

370-372 Magnet unit

374 N pole direction

376 magnetic field lines

Claims (24)

1. a real-time noble gas polarization generator comprises a cavity, a heat-insulation unit, and a base bottle, a heating source and intensifies the unit, it is characterized in that:

Described cavity has loam cake and the lower cover that is made of the high permeability material, and identical first and second magnet unit of magnetic direction is in order to produce a magnetic field, described first and second magnet unit is connected to respectively the both sides of described loam cake and described lower cover, the core of described loam cake and the relatively described cavity of described lower cover for equidistantly guiding described magnetic field to produce a uniform magnetic field space in described inside cavity, and formation screen effect;

Described heat-insulation unit is positioned at described cavity, and has a furnace space temperature is remained within the scope of being scheduled to;

Described base bottle is arranged in described furnace space, in order to load noble gas;

Described heating source is in order to provide in the hot extremely described furnace space to keep described basic bottle temperature in described predetermined scope;

The described unit that intensifies passes through described base bottle in order to produce a specific wavelength and the polarization laser beam identical with the magnetic direction of described magnetic field space, with the interior noble gas of the described base bottle of polarization,

Wherein, described high permeability material comprises dilval.

2. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described polarization laser beam comprises round polar biased laser beam.

3. real-time noble gas polarization generator as claimed in claim 1, it is characterized in that, described loam cake has first and second extension edge lid, described lower cover has the 3rd and the 4th extension edge lid, described the first magnet unit is between the described first and the 3rd extension edge lid, and described the second magnet unit is between the described second and the 4th extension edge lid.

4. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described first and second magnet unit comprises:

One first permanent magnet;

One second permanent magnet;

One sidewall, described sidewall is made of described high permeability material, and between described first and second permanent magnet, to be connected in series described first and second permanent magnet.

5. real-time noble gas polarization generator as claimed in claim 4 is characterized in that, described sidewall has first and second extension edge lid and engages respectively described first and second permanent magnet.

6. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described heat-insulation unit is made of the material of tool heat insulation effect.

7. real-time noble gas polarization generator as claimed in claim 6 is characterized in that, described heat-insulation unit is made of glass or calcium silicate board.

8. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described heating source comprises pipeline or the device that constant hot blast is provided.

9. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described heating source comprises pipeline or the device that constant hot material is provided.

10. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, described heating source comprises that one is connected to the quartz ampoule of heating air gun.

11. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, the described unit that intensifies comprises:

One laser is positioned at outside the described cavity, in order to produce a laser beam;

One reflector element is positioned at described cavity, in order to reflect described laser beam, makes described laser beam by described base bottle;

One polar biased unit is between described laser and described base bottle, with the described laser beam of polar biased.

12. real-time noble gas polarization generator as claimed in claim 11 is characterized in that described reflector element comprises speculum or prism.

13. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, the described unit that intensifies comprises:

One laser is positioned at outside the described cavity, in order to produce a laser beam;

One reflector element is positioned at described cavity, in order to reflection and the described laser beam of polar biased, makes described laser beam by described base bottle.

14. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, more comprises a heat insulation layer, between described cavity and described heat-insulation unit.

15. real-time noble gas polarization generator as claimed in claim 14 is characterized in that described heat insulation layer comprises heat-transfer arrangement.

16. real-time noble gas polarization generator as claimed in claim 15 is characterized in that described heat-transfer arrangement comprises glass tube, wherein the gas by temperature control.

17. real-time noble gas polarization generator as claimed in claim 14 is characterized in that, more comprises a heat insulating mattress, between described heat insulation layer and described heat-insulation unit.

18. real-time noble gas polarization generator as claimed in claim 1 is characterized in that, more comprises a malcoils, is positioned near the described base bottle, in order to emission and received RF signal, to detect the polarization degree of described noble gas.

19. the carrying case of a polarization noble gas comprises a cavity and a base bottle, it is characterized in that:

Described cavity has loam cake and the lower cover that is made of the high permeability material, and identical first and second magnet unit of magnetic direction is in order to produce a magnetic field, described first and second magnet unit is connected to respectively the both sides of described loam cake and described lower cover, the central part of described loam cake and the relatively described cavity of described lower cover for equidistantly guiding described magnetic field to produce a uniform magnetic field space in described inside cavity, and formation screen effect;

Described base bottle is arranged in described cavity, and inside has the polarization noble gas,

Wherein, described high permeability material comprises dilval.

20. the carrying case of polarization noble gas as claimed in claim 19, it is characterized in that, described loam cake has first and second extension edge lid, described lower cover has the 3rd and the 4th extension edge lid, described the first magnet unit is between the described first and the 3rd extension edge lid, and described the second magnet unit is between the described second and the 4th extension edge lid.

21. the carrying case of polarization noble gas as claimed in claim 19 is characterized in that, described first and second magnet unit comprises:

One first permanent magnet;

One second permanent magnet;

One sidewall, described sidewall is made of described high permeability material, and between described first and second permanent magnet, to be connected in series described first and second permanent magnet;

22. the carrying case of polarization noble gas as claimed in claim 21 is characterized in that, described sidewall has first and second extension edge lid and engages respectively described first and second permanent magnet.

23. the carrying case of polarization noble gas as claimed in claim 19 is characterized in that, comprises that more a collision prevention device is between described cavity and described base bottle.

24. the carrying case of polarization noble gas as claimed in claim 19 is characterized in that, more comprises a malcoils, is positioned near the described base bottle, in order to emission and received RF signal, to detect the polarization degree of described polarization noble gas.

Images