CN110107736B - Phase-change micro-valve device - Google Patents
Phase-change micro-valve device Download PDFInfo
- Publication number
- CN110107736B CN110107736B CN201910371612.4A CN201910371612A CN110107736B CN 110107736 B CN110107736 B CN 110107736B CN 201910371612 A CN201910371612 A CN 201910371612A CN 110107736 B CN110107736 B CN 110107736B
- Authority
- CN
- China
- Prior art keywords
- fluid
- micro
- flow channel
- heat
- phase change
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000012530 fluid Substances 0.000 claims abstract description 251
- 230000008859 change Effects 0.000 claims abstract description 81
- 238000012545 processing Methods 0.000 claims abstract description 11
- 239000007788 liquid Substances 0.000 claims description 31
- 239000007769 metal material Substances 0.000 claims description 31
- 239000004020 conductor Substances 0.000 claims description 25
- 238000002844 melting Methods 0.000 claims description 12
- 230000008018 melting Effects 0.000 claims description 8
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 6
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 3
- 229910052786 argon Inorganic materials 0.000 claims description 3
- 238000004891 communication Methods 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims 1
- 239000002470 thermal conductor Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 230000010354 integration Effects 0.000 abstract description 6
- 239000012071 phase Substances 0.000 description 75
- 239000007787 solid Substances 0.000 description 20
- 239000000463 material Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 239000011148 porous material Substances 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 230000017525 heat dissipation Effects 0.000 description 4
- 238000003672 processing method Methods 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 239000007790 solid phase Substances 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 239000004205 dimethyl polysiloxane Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 230000033228 biological regulation Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 230000001502 supplementing effect Effects 0.000 description 2
- 229910001152 Bi alloy Inorganic materials 0.000 description 1
- -1 Polydimethylsiloxane Polymers 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 238000007877 drug screening Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000005459 micromachining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000001259 photo etching Methods 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000012163 sequencing technique Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/002—Actuating devices; Operating means; Releasing devices actuated by temperature variation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K99/00—Subject matter not provided for in other groups of this subclass
- F16K99/0001—Microvalves
- F16K99/0003—Constructional types of microvalves; Details of the cutting-off member
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K99/00—Subject matter not provided for in other groups of this subclass
- F16K99/0001—Microvalves
- F16K99/0034—Operating means specially adapted for microvalves
- F16K99/0036—Operating means specially adapted for microvalves operated by temperature variations
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Temperature-Responsive Valves (AREA)
Abstract
The invention relates to the technical field of microfluidics, and provides a phase change micro valve device which comprises a fluid micro flow channel and a heat conduction flow channel, wherein a first end of the heat conduction flow channel is attached to the fluid micro flow channel, a second end of the heat conduction flow channel is connected with a cold source system and/or a heat source system, the cold source system comprises cold source fluid, the heat source system comprises heat source fluid, and a microporous structure is arranged at a position where the heat conduction flow channel and the fluid micro flow channel are connected with each other. The invention provides a phase-change micro valve device, which simplifies the structure of the device and the micro processing and manufacturing process, realizes microminiaturization and integration, and has the characteristics of low cost, simple operation, good controllability and wide compatibility.
Description
Technical Field
The invention relates to the technical field of microfluidics, in particular to a phase-change micro-valve device.
Background
The microfluidic technology can realize the control of microfluid in a microchannel, and is widely applied to the fields of gene sequencing, drug screening, new material research and development, disease diagnosis and the like.
The micro valve is used as a key component in a microfluidic system, and plays roles in closing or opening a micro channel, changing the flow direction of a micro fluid and the like in a complicated micro channel network. The micro valve is matched with the components of other micro-fluidic systems, so that the functions of orderly sample injection, mixing, storage and the like of various micro-fluids can be realized.
At present, the micro valves commonly used in the micro-fluidic technology include pneumatic valves, mechanical valves, phase change valves and the like. Compared with other types of micro valves, the phase change valve has the advantages of no moving parts, simple manufacture and the like, and the micro ice valve is a common phase change valve.
The micro-ice valve blocks the fluid micro-flow channel by cooling and solidifying a part of fluid (working medium) in the fluid micro-flow channel, so that the function of closing the fluid micro-flow channel is realized; and then heating and melting the solidified working medium into liquid to realize the function of opening the fluid micro-channel.
A common micro-ice valve consists of a fluid micro-channel and a semiconductor refrigeration sheet, which is typically placed under the fluid micro-channel. The semiconductor refrigerating sheet has the refrigerating and heating functions to change the phase state of fluid inside the fluid micro flow channel, so as to realize the aim of closing or opening the fluid micro flow channel. In order to quickly close and open the micro flow channel, a semiconductor refrigerating sheet is adopted, and a multi-stage semiconductor refrigerating sheet and a complex heat dissipation system are generally required, so that the problems of low heat dissipation efficiency, slow state transition, complex structure, high cost and the like are solved.
Disclosure of Invention
First, the technical problem to be solved
The present invention aims to solve at least one of the technical problems existing in the prior art or related art: the phase-change micro valve comprises the following components of complex structure, slow switching of closed and open states and high cost.
The purpose of the invention is that: the phase-change micro valve device has the characteristics of low cost, simplicity in operation, good controllability and wide compatibility, and simplifies the structure of the device and the micromachining manufacturing process, realizes microminiaturization and integration.
(II) technical scheme
In order to solve the technical problems, the invention provides a phase change micro valve device, which comprises a fluid micro flow channel and a heat conduction flow channel, wherein a first end of the heat conduction flow channel is attached to the fluid micro flow channel, a second end of the heat conduction flow channel is connected with a cold source system and/or a heat source system, the cold source system comprises cold source fluid, the heat source system comprises heat source fluid, and a micropore structure is arranged at a position where the heat conduction flow channel and the fluid micro flow channel are connected with each other.
In some technical solutions, preferably, the microporous structures are uniformly distributed on the end surfaces of the heat conducting flow channels and the fluid micro flow channels, and the heat conductors in the heat conducting flow channels and the working medium in the fluid micro flow channels are separated on two sides of the microporous structures.
In some embodiments, preferably, the processing method of the microporous structure includes photolithography processing, and a boss is formed between adjacent microporous structures.
In some embodiments, preferably, two heat conducting channels are symmetrically connected to two sides of the fluid micro-channel.
In some embodiments, preferably, the fluid micro-flow channel includes a plurality of inlets and a plurality of outlets, one inlet and one outlet that are mutually communicated form a fluid micro-flow, and a side surface of each fluid micro-flow is connected with the heat conducting channel.
In some embodiments, preferably, the fluidic microchannel includes an inlet, a plurality of outlets, or a plurality of inlets, an outlet, the fluidic microfluidics forming a plurality of shared inlets or outlets;
or the fluid micro-channel comprises a plurality of inlets and a plurality of outlets, so as to form a plurality of staggered communicated fluid micro-streams.
In some embodiments, preferably, the heat conducting channel is filled with a heat conductor, and the heat conductor is in direct contact with the cold source fluid and the heat source fluid.
In some embodiments, preferably, the heat conduction flow channel is filled with a low-melting-point metal material, and the low-melting-point metal material includes a metal simple substance and a metal alloy.
In some embodiments, preferably, the cold source fluid comprises a low temperature liquid fluid, and the temperature of the low temperature liquid fluid ranges from-200 ℃ to-100 ℃; the heat source fluid comprises a liquid or gaseous high temperature fluid having a temperature in the range of 40 ℃ to 60 ℃.
In some embodiments, preferably, the cryogenic liquid fluid comprises liquid nitrogen, liquid oxygen, liquid argon; the high temperature fluid comprises hot steam and hot water.
In some embodiments, preferably, at least one containing structure is connected to the second end of the heat conducting channel, and the containing structure is used for containing the cold source fluid and/or the heat source fluid.
In some embodiments, preferably, one of the accommodating structures is connected to a plurality of second ends of the heat conducting channels, and the first end of each heat conducting channel is connected to the fluid micro-channel.
(III) beneficial effects
Compared with the prior art, the invention has the following advantages:
(1) The method is characterized in that a cold source system or a heat source system is adopted to provide cold or heat for a working medium, the phase state of the working medium is changed, cold source fluid of the cold source system enables the working medium to be cooled and cooled to be changed into a solid phase, a fluid micro-channel is closed to block the flow of the working medium, heat source fluid of the heat source system enables the working medium to absorb heat and raise temperature to be changed into a flowing state, and the fluid micro-channel is opened to enable the working medium to flow; the cold source fluid and the heat source fluid respectively provide cold and heat, so that the working medium is ensured to rapidly change phase state, the structure is simplified, and the cost is reduced;
(2) And the cold source system and the heat source system transfer cold or heat to the working medium through the heat conduction flow channel, so that the mixing of cold source fluid and heat source fluid with the working medium is avoided, and the cleanness of various fluids is ensured.
Drawings
FIG. 1 is a schematic diagram of a single-sided opening and closing of a single fluidic microchannel of a phase change microvalve device according to one embodiment of the present invention;
FIG. 2 is a schematic view of a partially enlarged structure of the phase change micro valve device of FIG. 1 according to the present invention;
FIG. 3 is a schematic diagram of a preferred structure for double-sided opening and closing of a single fluidic microchannel of a phase change microvalve device of the present invention;
FIG. 4 is a schematic diagram of a preferred embodiment of the phase change micro valve device according to the present invention with simultaneous on/off adjustment of multiple fluidic micro channels;
FIG. 5 is a schematic diagram of a preferred embodiment of multi-fluid micro-branch on-off regulation of a phase change micro-valve device according to the present invention;
FIG. 6 is a schematic diagram of another preferred embodiment of multi-fluid micro-branch on-off regulation of a phase change micro-valve device of the present invention;
in the figure, 1. A containment structure; 2. a microporous structure; 3. a heat conduction flow channel; 4. a fluidic microchannel; 5. a phase change region; 6. a boss.
Detailed Description
The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.
With the development of micro-nano processing technology, micro-fluidic devices tend to be miniaturized and integrated. Key components in the microfluidic system, such as a micro valve, need a structure which is convenient for miniaturization and integration, and have the characteristics of convenient processing and manufacturing, low cost, simple operation and the like. When the phase change valve works, other substances are not needed to be added, pollution to fluid in the micro-flow channel is avoided, and the phase change valve is suitable for flow channel opening and closing adjustment in a micro-flow control system. However, the existing phase-change valve has the problems of complex structure, poor heat dissipation effect, high cost and the like, and the phase-change micro-valve device provided by the invention has the characteristics of simplifying the structure of the device and the micro-processing manufacturing process, realizing microminiaturization and integration, along with low cost, simplicity in operation, good controllability and wide compatibility.
Referring to fig. 1-6, the present invention provides a preferred embodiment of a phase change micro valve device, which includes a fluid micro flow channel 4 and a heat conducting flow channel 3, wherein a working medium flows in the fluid micro flow channel 4, and the flow state of the working medium needs to be adjusted by adjusting the on-off state of the fluid micro flow channel 4, and the heat conducting flow channel 3 conducts cold or heat to adjust the phase state of the working medium in the fluid micro flow channel 4, so as to realize on-off adjustment of the fluid micro flow channel 4.
The first end of the heat conduction flow channel 3 is attached to the fluid micro-flow channel 4, and the second end of the heat conduction flow channel 3 is connected with the cold source system and/or the heat source system. The cold source system and the heat source system transfer cold or heat to the fluid micro-flow channel 4 through the heat conducting flow channel 3, when the cold source system transfers cold to the fluid micro-flow channel 4, the working medium in the fluid micro-flow channel 4 is cooled until the working medium changes in phase state, and the working medium is cooled to be converted into a solid phase to block the flow of the working medium in the fluid micro-flow channel 4. When the working medium needs to be started to flow in the fluid micro-flow channel 4, the cold source system finishes transmitting cold energy to the fluid micro-flow channel 4, and the heat source system transmits heat to the fluid micro-flow channel 4 through the heat conducting flow channel 3, so that the phase state of the working medium in the fluid micro-flow channel 4 is changed to conduct the fluid micro-flow channel 4, the working medium absorbs the heat and is changed from a solid phase to a liquid phase or a gas phase, and the working medium returns to a flowing state.
The fluid micro-channel 4 and the heat conduction channel 3 are integrated on the micro-fluidic chip, the fluid micro-channel 4 and the heat conduction channel 3 are coplanar, the heat conduction channel 3 is provided with the side face of the fluid micro-channel 4, and the heat conduction channel 3 is attached to the side face of the fluid micro-channel 4. The second end of the heat conducting runner 3 may also be set as an inlet of a heat conductor, which is poured into the heat conducting runner 3 through the second end of the heat conducting runner 3.
As shown in fig. 1 and 2, the end surfaces of the heat conduction flow channel 3 and the fluid micro flow channel 4, which are mutually attached, are provided with the micro-pore structure 2, the heat conductor in the heat conduction flow channel 3 transmits heat or cold to the working medium in the fluid micro flow channel 4 through the micro-pore structure 2, and the heat conductor and the working medium are directly contacted through the micro-pore structure 2 to transmit heat or cold, but the micro-pore structure 2 can prevent the heat conductor from flowing into the fluid micro flow channel 4 and the working medium from flowing into the heat conduction flow channel 3, and the micro-pore structure 2 not only has the function of transmitting heat or cold, but also can separate the heat conductor and the working medium, prevent the heat conductor and the working medium from being mixed, and ensure the independence and cleanness of the heat conductor and the working medium.
The region in the fluid micro-channel 4 corresponding to the mutually attached end surfaces of the heat-conducting channel 3 and the fluid micro-channel 4 forms a phase change region 5, the range of the phase change region 5 can be expanded or contracted in the length direction of the fluid micro-channel 4 by the position of the mutually attached end surface of the heat-conducting channel 3 and the fluid micro-channel 4, and the range of the phase change region 5 is related to the cold energy and heat provided by the cold source system and the heat source system to the heat-conducting channel 3.
The cold source fluid or the heat source fluid can quickly change the temperature of the working medium in the phase change region 5 around the microporous structure 2, thereby causing the working medium to change phase, and further closing or opening the fluid micro-channel 4.
The cold source system or the heat source system transmits cold or heat to the heat conduction flow channel 3, the heat conduction flow channel 3 transmits the cold or heat to the working medium in the fluid micro-flow channel 4, the heat conductor in the heat conduction flow channel 3 directly transmits the cold or heat to the working medium through the micropore structure 2, the transmission efficiency of the cold or heat is improved, the separation between the heat conductor and the working medium is maintained, and the working medium is prevented from being polluted by fluid mixing.
The heat conduction flow channel 3 is filled with a heat conductor, the heat conductor plays a role in cold energy or heat transmission, and the heat conductor is in direct contact with the cold source fluid of the cold source system and the heat source fluid of the heat source system in the accommodating structure 1, so that the heat conduction efficiency is improved, and the fluid micro flow channel 4 is quickly opened and closed. The inlet of the heat conduction flow channel 3 is of an open structure, and cold source fluid or heat source fluid in the accommodating structure 1 directly contacts with the heat conductor through the inlet of the heat conduction flow channel 3.
Specifically, the heat conduction runner 3 is filled with a low-melting-point metal material, the heat conductor comprises the low-melting-point metal material, the low-melting-point metal material belongs to a good heat conductor, the heat conduction effect is good, the performance is stable, and the molecular tension is large and cannot penetrate through the micropore structure 2. Preferably, the low melting point metal material comprises a metal simple substance and a metal alloy, preferably bismuth or bismuth alloy.
The material of the micro-fluidic chip belongs to a poor heat conductor, and Polydimethylsiloxane (PDMS), glass or quartz is preferably adopted to block heat dissipation, and the low-melting-point metal material has better heat conduction performance than the material of the micro-fluidic chip, so that heat conduction is ensured.
After the low-melting-point metal material is heated by the heat source fluid to become liquid, the microporous structure 2 can prevent the liquid-state low-melting-point metal material from entering the fluid micro-channel under the action of surface tension. Meanwhile, the working medium (solid or liquid) is blocked by the low melting point metal material from entering the heat conduction flow path 3. When the temperature in the heat conduction flow channel 3 is reduced and returns to the freezing point of the low-melting-point metal material, the low-melting-point metal material is cooled and solidified into a solid in the heat conduction flow channel 3. Generally, the low-melting-point metal material is solid at room temperature, and therefore, when the fluid micro flow channel 4 flows through the working medium under the drive of pressure at room temperature, the low-melting-point metal material does not flow out of the heat conduction flow channel 3 or wash away the low-melting-point metal material.
At room temperature, a small amount of solid low-melting point metal material can be left to be in direct contact with cold source fluid or heat source fluid. The microfluidic chip material belongs to a poor conductor of heat, and the low-melting point metal material belongs to a good conductor of heat. Therefore, after the cold source fluid or the heat source fluid is contacted with the low-melting point metal material, heat can be quickly transferred to the fluid in the phase change region 5 through the low-melting point metal material without being diffused to the micro-fluidic chip material around the hot runner 3. The size of the range of the phase change region 5 can be varied by controlling the amount of cold provided by the cold source fluid. Therefore, the phase-change micro valve device has the advantages of simplicity in operation, good controllability, wide compatibility and the like.
The cold source fluid of the cold source system comprises low-temperature liquid fluid, the temperature range of the low-temperature liquid fluid is between-200 ℃ and-100 ℃, and the cold source fluid is preferably liquid nitrogen, liquid oxygen, liquid argon, liquid air or the like; the heat source fluid comprises liquid or gaseous high-temperature fluid, the temperature of the high-temperature fluid ranges from 40 ℃ to 60 ℃, and hot air and hot water are preferably selected.
The second end of the heat conduction flow channel 3 is at least connected with a containing structure 1, and the containing structure 1 is used for containing cold source fluid and/or heat source fluid.
The second end of the heat conduction flow channel 3 can be connected with a containing structure 1, the cold source system and the cold source fluid in the cold source system share the containing structure 1, and when the fluid micro flow channel 4 needs to be closed, the cold source system supplies the cold source fluid into the containing structure 1 until the working medium in the fluid micro flow channel 4 is converted into a solid phase, and the working medium is blocked from flowing; when the fluid micro-flow channel 4 needs to be opened, cold source fluid of the cold source system is led out of the accommodating structure 1, the heat source system provides heat source fluid into the accommodating structure 1, the working medium absorbs heat of the heat source fluid to change the flow state, the fluid micro-flow channel 4 is opened, and the working medium stably flows.
In addition, the second end of the heat conduction flow channel 3 can be connected with two containing structures 1, cold source fluid of the cold source system and heat source fluid of the heat source system are respectively led into one containing structure 1, when the fluid micro flow channel 4 needs to be closed, the cold source system is led into the containing structure 1 communicated with the cold source system, when the fluid micro flow channel 4 needs to be opened, the cold source fluid in the cold source system is led out of the containing structure 1, and the heat source system is led into the containing structure 1 communicated with the heat source system.
Furthermore, the second end of the heat conducting runner 3 may be further connected with a plurality of accommodating structures 1, the cold source system and the heat source system may share the plurality of accommodating structures 1, when the fluid micro-runner 4 needs to be closed, the cold source fluid is led into all the accommodating structures 1, and when the fluid micro-runner 4 needs to be opened, the cold source fluid is led out of the accommodating structures 1 and the heat source fluid is led into all the accommodating structures 1. The plurality of accommodating structures 1 can also be allocated to the cold source system and the heat source system as required, for example, the accommodating structures 1 comprise five, two communicating cold source systems and three communicating heat source systems.
The receiving structure 1 may be provided as a receiving groove, a receiving pipe, a receiving ball, etc.
Further, the microporous structures 2 are uniformly distributed on the end surfaces of the heat conduction flow channels 3 and the fluid micro flow channels 4, and the contact area between the heat conductor and the working medium is increased in a uniformly distributed mode of the microporous structures 2.
The microporous structure 2 is preferably a microwell or array of microwells. The shape of the micropores is preferably circular, rectangular, or trapezoidal. The distance between the micropores is preferably between 5 and 20 microns.
The processing method of the microporous structures 2 comprises photoetching, and a boss 6 is formed between adjacent microporous structures 2. The processing method of the microporous structure 2 may also include laser processing, etc., and may be any processing method capable of processing the microporous structure 2 having a suitable size.
In the phase change micro valve device, a heat conduction flow channel 3 and a fluid micro flow channel 4 are integrated on a micro flow control chip and are manufactured synchronously by adopting a micro processing manufacturing process. Preferably, the micro-processing manufacturing process adopts a conventional soft etching technology, the same mask is adopted, the heat conduction flow channel 3 and the fluid micro-flow channel 4 which are equal in height and coplanar are etched on the micro-flow control chip material, and the microporous structure 2 at the intersection of the heat conduction flow channel 3 and the fluid micro-flow channel 4 can be synchronously manufactured. Specifically, a micropore is formed at the second end of the heat conduction flow channel 3 by using a puncher, the micropore is used as a cold source fluid groove or a heat source fluid containing structure 1, the diameter of the containing structure 1 is preferably between 5 micrometers and 2 micrometers, and the containing structure 1 is equal to the heat conduction flow channel 3 in height. Preferably, the microfluidic chip employs PDMS as a base material. Therefore, the micro-scale phase change micro valve can be manufactured by the micro-processing manufacturing process, and is simple to manufacture and low in cost. And the phase change micro valve device is very convenient to integrate a plurality of phase change micro valve devices together or integrate the phase change micro valve device and other components in a micro fluidic system together.
In some embodiments, as shown in fig. 1, the fluidic micro flow channel 4 has an inlet and an outlet, and the thermal conduction flow channel 3 is disposed on only one side of the fluidic micro flow channel 4. The working principle of the phase-change micro valve device is as follows: when the fluid micro-channel 4 needs to be closed, the containing structure 1 connected with the second end of the heat conduction channel 3 is a containing groove for containing cold source fluid, a proper amount of cold source fluid is regularly placed in the containing groove, the temperature of the low-melting-point metal material in the heat conduction channel 3 is rapidly reduced, the liquid working medium in the phase change area 5 is cooled and solidified into solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5. The size of the phase change area 5 changes along with the change of the amount of cold source fluid placed in the accommodating groove; when the fluid micro-channel 4 needs to be opened, the containing structure 1 connected with the second end of the heat conducting channel 3 is a containing groove for containing heat source fluid, and after the heat source fluid is placed in the containing groove, the temperature of the low-melting-point metal material in the heat conducting channel 3 is quickly increased, so that the solid working medium in the phase change region 5 is heated and melted into liquid, and the conduction of the fluid micro-channel 4 is realized.
In some technical schemes, as shown in fig. 3, two heat conducting runners 3 are symmetrically arranged on two sides of a fluid micro runner 4, each heat conducting runner 3 is connected with a cold source system and a heat source system, and a micropore structure 2 is arranged at the connection part of each heat conducting runner 3 and the fluid micro runner 4. Each of the heat conduction runners 3 is filled with a low melting point metal material and has one inlet each.
The fluidic microchannel 4 comprises an inlet, an outlet, or an inlet, a plurality of outlets, or a plurality of inlets, an outlet, or a plurality of inlets, a plurality of outlets. When the inlet or the outlet of the fluid micro-channel 4 is larger than one, the fluid micro-channel 4 comprises fluid micro-streams, one inlet and one outlet which are mutually communicated form one fluid micro-stream, and each fluid micro-stream is symmetrically provided with two heat conducting channels 3.
The working principle of the phase-change micro valve device is as follows: when the fluid micro-channel 4 needs to be closed, the cold source system fills cold source fluid into the accommodating structure 1, a proper amount of cold source fluid is regularly put into the accommodating structure 1 connected with the two heat conducting channels 3 at the same time, the temperature of the low-melting-point metal material is rapidly reduced, a liquid working medium in the phase change area 5 is cooled and solidified into a solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5. When the fluid micro-channel 4 needs to be opened, the heat source system fills heat source fluid into the accommodating structure 1, the heat source fluid is simultaneously put into the accommodating structure 1 of the two heat conducting channels 3, the temperature of the low-melting-point metal material is rapidly increased, and then the solid working medium in the phase change region 5 is heated and melted into liquid.
Compared with the mode that the heat conduction flow channel 3 is arranged on one side of the fluid micro flow channel 4, the heat conduction flow channel 3 is additionally arranged on the other side of the fluid micro flow channel 4, so that the response speed of the phase change micro valve device can be increased, and the working stability of the phase change micro valve device can be improved.
In some embodiments, as shown in fig. 4, one accommodating structure 1 may simultaneously provide a cold source fluid and/or a heat source fluid to a plurality of heat conducting channels 3, a second end of the plurality of heat conducting channels 3 is connected to one accommodating structure 1, the plurality of heat conducting channels 3 are integrated on one accommodating structure 1, a first end of each heat conducting flow is connected to a fluid micro-channel 4, and each guide channel provides cold or heat to the fluid micro-channel 4 connected thereto.
Preferably, the heat conducting runners 3 are connected to the side wall of the accommodating structure 1 and radiate towards the periphery of the accommodating structure 1, and each heat conducting runner 3 can be connected with one fluid micro-runner 4, and meanwhile, a plurality of fluid micro-runners 4 are adjusted, so that the efficiency is improved. In addition, all the heat conducting runners 3 can be connected to one annular or special-shaped fluid micro-runner 4, and different parts on one fluid micro-runner 4 are opened and closed simultaneously so as to adjust the on-off of the fluid micro-runner 4 and other runners.
In addition, an additional accommodating structure can be connected to each heat conducting runner 3 for supplementing cold or heat. And the accommodating structure is additionally connected to the heat conducting flow channel 3 and is used for supplementing the cooling capacity or heat, so that the heat conducting flow channel is suitable for the fluid micro flow channels 4 or the fluid micro flows with different cooling capacity or heat requirements.
Specifically, there are 6 fluidic microchannels 4, each fluidic microchannel 4 having a separate inlet and outlet. The number of the heat conduction flow channels 3 is equal to the number of the fluid micro flow channels 4, 6 heat conduction flow channels 3 are arranged, each heat conduction flow channel 3 is intersected with only one fluid micro flow channel 4, and a micropore structure 2 is arranged at the intersection. The heat conducting runners 3 are filled with a low melting point metal material and share one receiving structure 1. The number of the phase change areas 5 is equal to the number of the fluid micro-channels 4, and 6 phase change areas are arranged. The number of the fluidic microchannels 4 is not limited to 6, and may be set according to actual needs.
The working principle of the phase change micro valve device is as follows: the common accommodating structure 1 is connected with a cold source system and/or a heat source system, a plurality of heat conducting flow channels 3 are connected to the accommodating structure 1, and the accommodating structure 1 simultaneously provides cold or heat for all the heat conducting flow channels 3 and simultaneously controls the opening and closing of a plurality of fluid micro flow channels 4 and a plurality of fluid micro flows; when a plurality of fluid micro-channels 4 or a plurality of fluid micro-streams in the fluid micro-channels 4 need to be closed, the containing structure 1 is connected with a cold source system, the cold source system regularly places a proper amount of cold source fluid into the containing structure 1, the temperature of working media in all the fluid micro-channels 4 or all the fluid micro-streams is rapidly reduced, the liquid working media in the phase change area 5 of the fluid micro-channels 4 or the fluid micro-streams are cooled and solidified into solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5. When the fluid micro-flow channel 4 or the fluid micro-flow channel 4 needs to be opened, the accommodating structure 1 is connected with a heat source system, and the heat source system regularly puts a proper amount of heat source fluid into the accommodating structure 1, so that the temperature of the fluid micro-flow channel or the working medium on the fluid micro-flow channel 4 is quickly increased, and then the solid working medium in the phase change region 5 is heated, and is melted into liquid.
According to the technical scheme, the components can be integrated together easily, the plurality of heat conduction runners 3 share the accommodating structure 1, the opening and closing states of the plurality of fluid micro runners 4 can be controlled simultaneously, and the integration level of the microfluidic chip is improved relative to the technical scheme that one heat conduction runner 3 is connected with one independent accommodating structure 1.
In some technical solutions, as shown in fig. 5 and 6, the fluid micro-flow channel 4 includes a plurality of fluid micro-flows, an inlet and an outlet that are mutually communicated form a fluid micro-flow, and a side surface of each fluid micro-flow is connected with a heat conducting flow channel 3, and the heat conducting flow channels 3 are provided with one or two symmetrically arranged.
As shown in fig. 5, the fluidic microchannel 4 includes an inlet, a plurality of outlets, or a plurality of inlets, an outlet, forming a plurality of fluidic microstream of common inlet or outlet; as shown in fig. 6, the fluidic microchannel 4 includes a plurality of inlets and a plurality of outlets, forming a plurality of fluid microstream in staggered communication.
Specifically, a plurality of fluid micro-streams are integrated on one fluid micro-channel 4, so that not only can the fluid micro-streams be opened and closed, but also the flow direction of the fluid in the fluid micro-channel 4 can be changed. As shown in fig. 5, the number of inlets and outlets of the fluidic micro flow channel 4 is not equal, and specifically, the fluidic micro flow channel 4 has one inlet and 6 outlets, and the inlet and the outlet may form one tributary to form 6 fluidic micro streams. The number of the heat conducting channels 3 is equal to the number of the outlets of the fluid micro-channels 4, 6 heat conducting channels 3 are arranged, each heat conducting channel 3 is intersected with only one fluid micro-flow or independent fluid micro-channels 4, and a micropore structure 2 is arranged at the intersection. The heat conducting runners 3 are filled with a low melting point metal material and have an inlet. The number of the phase change areas 5 is equal to the number of the heat conduction runners 3, and the number of the phase change areas is 6.
Each fluid micro-flow may be connected with one heat conducting channel 3, or two heat conducting channels 3 are symmetrically arranged, and each heat conducting channel 3 is connected to a cold source system or a heat source system.
The working principle of the phase change micro valve device is as follows: when one or more fluid micro-streams in the fluid micro-stream 4 need to be closed, the containing structure 1 connected with the heat conducting channel 3 on the fluid micro-stream is connected with a cold source system, a proper amount of cold source is regularly placed in the containing structure 1, the temperature of the liquid working medium in the phase change area 5 on the fluid micro-stream is rapidly reduced, the working medium is cooled and solidified into solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5. When one or more fluid microfluidics in the fluid microfluidics 4 need to be opened, the containing structure 1 connected with the heat conducting runner 3 on the fluid microfluidics is connected with a heat source system, after the heat source is introduced into the containing structure 1, the temperature of the phase change region 5 on the fluid microfluidics is quickly increased, and then the phase state of a working medium in the phase change region 5 on the fluid microfluidics is changed, and the working medium is melted into liquid.
As shown in fig. 5, a structure of a fluid micro-channel 4 with different forms is provided, so as to adapt to micro-fluidic chips with different structures, increase the integration diversity of the phase-change micro-valve device and widen the application range of the micro-ice valve device.
The configuration of the fluid micro flow channel 4 is not limited to the configuration shown in fig. 5, and the fluid micro flow channel 4 may have one inlet, a plurality of outlets, or a plurality of inlets and one outlet.
Further, as shown in fig. 6, the fluidic micro flow channel 4 includes a plurality of inlets and a plurality of outlets, and any one inlet and one outlet are communicated to form a fluidic micro flow, so that a plurality of staggered communicated fluidic micro flows can be formed.
Specifically, the fluidic microchannel 4 has 3 inlets and 3 outlets, each inlet and each outlet can form a fluidic microstream, and the branches are intersected with each other to form a plurality of "+" intersections. Each fluid microfluid is connected with a heat conduction flow channel 3, the number of the heat conduction flow channels 3 is twice of that of a "+" type intersection, and 4 heat conduction flow channels 3 are arranged. Each heat conduction runner 3 is crossed with the fluid micro-runner 4, and a microporous structure 2 is arranged at the crossing part, phase change areas 5 are formed at the crossing part, and the number of the phase change areas 5 is equal to that of the heat conduction runners 3, and the number of the phase change areas is 4.
The principle of changing the flow direction of fluid by using the phase change micro valve device is as follows: by regularly controlling the phase state of the working medium in the phase change region 5, the flow direction of the working medium at the cross of the "+" shape can be changed.
For example, the working medium is first allowed to flow from the upper end and the left end of the "+" shaped intersection to only the lower end of the "+" shaped intersection. At this time, the containing structure 1 of the heat conduction flow channel 3 at the right end of the "+" intersection is filled with cold source fluid, a proper amount of cold source fluid is regularly placed in the containing structure 1, the temperature of the low-melting-point metal material in the heat conduction flow channel 3 is rapidly reduced, the liquid working medium in the phase change area at the right end of the "+" intersection is cooled and solidified into solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5. And then the working medium flows from the upper end and the left end of the "+" shaped intersection to the right end of the "+" shaped intersection only. At this time, the heat source fluid is introduced into the accommodating structure 1 of the heat conduction flow channel 3 at the right end of the "+" shaped intersection, the heat source fluid is put into the accommodating structure 1, the temperature of the low-melting-point metal material in the heat conduction flow channel 3 is rapidly increased, and the solid working medium in the phase change region 5 at the right end of the "+" shaped intersection is melted into liquid. The containing structure 1 connected with the heat conduction flow channel 3 at the lower end of the "+" intersection is filled with cold source fluid, a proper amount of cold source fluid is regularly placed in the containing structure 1, the temperature of the low-melting-point metal material in the heat conduction flow channel 3 is rapidly reduced, a liquid working medium in the phase change area 5 at the lower end of the "+" intersection is cooled and solidified into solid, the solid can be kept for a long time, and the phase change is controlled to only occur in the phase change area 5.
The fluid micro-flow channels 4 form a multi-cross structure, and the opening and closing of each fluid micro-flow are regulated by regulating the phase states of the working media of the phase change areas 5 at different positions, so that the flow direction of the working media in the fluid micro-flow channels 4 is realized, and the flow direction of the fluid can be changed more simply.
In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.
Furthermore, in the description of the present invention, unless otherwise indicated, the meaning of "a plurality", "a plurality of groups" is two or more.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (10)
1. The phase change micro valve device is characterized by comprising a fluid micro flow channel and a heat conduction flow channel, wherein a first end of the heat conduction flow channel is attached to the fluid micro flow channel, a second end of the heat conduction flow channel is connected with a cold source system and/or a heat source system, the cold source system comprises cold source fluid, the heat source system comprises heat source fluid, and a microporous structure is arranged at a position where the heat conduction flow channel is connected with the fluid micro flow channel;
the heat conduction flow channel is filled with a heat conductor, and the heat conductor is in direct contact with the cold source fluid and the heat source fluid; the heat conductor in the heat conduction flow channel and the working medium in the fluid micro-flow channel are separated at two sides of the micropore structure; the thermal conductor comprises a low melting point metallic material.
2. The phase change microvalve device of claim 1, wherein the microporous structure is uniformly distributed on the end surfaces of the thermally conductive runners and the fluidic runners that are in contact with each other.
3. The phase change microvalve device of claim 2, wherein said microporous structure is fabricated by a process that includes photolithographic processing, with bosses formed between adjacent microporous structures.
4. The phase change microvalve device of claim 1, wherein two of said thermally conductive runners are symmetrically connected on either side of said fluid microchannel.
5. The phase change microvalve device of claim 1, wherein said fluid microchannel includes a plurality of inlets and a plurality of outlets, one inlet and one outlet in communication with each other forming a fluid microchannel, each of said fluid microchannel being connected to said thermally conductive channel on a side thereof.
6. The phase change microvalve device of claim 5, wherein said fluid microchannel includes an inlet, a plurality of outlets or a plurality of inlets, an outlet, said fluid microchannels forming a plurality of common inlets or outlets;
or the fluid micro-channel comprises a plurality of inlets and a plurality of outlets, so as to form a plurality of staggered communicated fluid micro-streams.
7. The phase change microvalve device of claim 1, wherein the low melting point metal material includes elemental metals and metal alloys.
8. The phase change microvalve device of claim 1, wherein said cold source fluid comprises a low temperature liquid fluid having a temperature in the range of-200 ℃ to-100 ℃; the heat source fluid comprises liquid or gaseous high-temperature fluid, and the temperature of the high-temperature fluid ranges from 40 ℃ to 60 ℃;
the low-temperature liquid fluid comprises liquid nitrogen, liquid oxygen and liquid argon;
the high temperature fluid comprises hot steam and hot water.
9. The phase change microvalve device of any one of claims 1-8, wherein the second end of the thermally conductive flow channel is coupled to at least one containment structure for containing a cold source fluid and/or a heat source fluid.
10. The phase change microvalve device of claim 9, wherein one of said containment structures is connected to a plurality of second ends of said thermally conductive runners, each of said thermally conductive runners having a first end connected to said fluid microchannel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910371612.4A CN110107736B (en) | 2019-05-06 | 2019-05-06 | Phase-change micro-valve device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910371612.4A CN110107736B (en) | 2019-05-06 | 2019-05-06 | Phase-change micro-valve device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110107736A CN110107736A (en) | 2019-08-09 |
| CN110107736B true CN110107736B (en) | 2024-04-16 |
Family
ID=67488328
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910371612.4A Active CN110107736B (en) | 2019-05-06 | 2019-05-06 | Phase-change micro-valve device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110107736B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111690378B (en) * | 2020-05-28 | 2022-06-28 | 明日加加科技有限公司 | Ultralow-temperature micro-nano fluid and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1580780A (en) * | 2003-08-08 | 2005-02-16 | 大连依利特分析仪器有限公司 | Temperature controlled micro separating system switching and cutting-off method and special device thereof |
| CN104833245A (en) * | 2015-05-21 | 2015-08-12 | 上海利策科技股份有限公司 | Multi-path micro-hole heat exchanger |
| CN107573704A (en) * | 2017-09-27 | 2018-01-12 | 北京工业大学 | A kind of phase transformation micro-valve based on conducing composite material and sensing thermal drivers |
| CN210344518U (en) * | 2019-05-06 | 2020-04-17 | 中国科学院理化技术研究所 | Phase change microvalve device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102009035292A1 (en) * | 2009-07-30 | 2011-02-03 | Karlsruher Institut für Technologie | Device for controlling the flow of fluids through microfluidic channels, methods of their operation and their use |
-
2019
- 2019-05-06 CN CN201910371612.4A patent/CN110107736B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1580780A (en) * | 2003-08-08 | 2005-02-16 | 大连依利特分析仪器有限公司 | Temperature controlled micro separating system switching and cutting-off method and special device thereof |
| CN104833245A (en) * | 2015-05-21 | 2015-08-12 | 上海利策科技股份有限公司 | Multi-path micro-hole heat exchanger |
| CN107573704A (en) * | 2017-09-27 | 2018-01-12 | 北京工业大学 | A kind of phase transformation micro-valve based on conducing composite material and sensing thermal drivers |
| CN210344518U (en) * | 2019-05-06 | 2020-04-17 | 中国科学院理化技术研究所 | Phase change microvalve device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110107736A (en) | 2019-08-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6536476B2 (en) | Flow rate-controlling method and microvalve therefor | |
| US7478792B2 (en) | Microvalve having magnetic wax plug and flux control method using magnetic wax | |
| US6679279B1 (en) | Fluidic valve having a bi-phase valve element | |
| US6382254B1 (en) | Microfluidic valve and method for controlling the flow of a liquid | |
| US6622746B2 (en) | Microfluidic system for controlled fluid mixing and delivery | |
| CA2683050A1 (en) | Microsystem capillary separations | |
| WO2004038318A2 (en) | Vapor escape microchannel heat exchanger | |
| KR20010024538A (en) | Micromixer | |
| CN106197117A (en) | A kind of micro-channel heat exchanger system | |
| CN105032518B (en) | Micro-fluidic chip heat dissipation device and manufacturing method thereof | |
| US7097811B2 (en) | Gravity-driven apparatus and method for control of microfluidic devices | |
| CN110107736B (en) | Phase-change micro-valve device | |
| JP2006187685A (en) | Microstructure, microreactor, heat exchanger and manufacturing method of microstructure | |
| CN210344518U (en) | Phase change microvalve device | |
| CN109579340A (en) | Miniature j-t refrigerator based on MEMS processing technology | |
| CN110645408A (en) | Electrowetting-driven liquid drop micro-valve liquid circulation control device | |
| CN110605147B (en) | A liquid crystal-based temperature control microvalve and its single and multi-stage control system | |
| CN109780318B (en) | Liquid metal microvalve device and microfluidic system provided with the same | |
| CN114917970A (en) | Micro-fluidic device | |
| Gui et al. | Microfluidic phase change valve with a two-level cooling/heating system | |
| TWI295725B (en) | Method and apparatus for efficient vertical fluid delivery for cooling a heat producing device | |
| CN110886901A (en) | Substrate, phase change valve and control method thereof | |
| CN117772306B (en) | A microfluidic chip and system for dilution refrigeration based on microdroplets | |
| WO2006121534A1 (en) | Thermally-powered nonmechanical fluid pumps using ratcheted channels | |
| US20040184967A1 (en) | Microfluidics switch with moving planes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |