Patent Application
20200406288
The present invention relates to a liquid film generation device and a liquid film cartridge using the same and particularly to a device generating a liquid film as a liquid sample from a liquid in a system for measuring characteristics of the electromagnetic waves transmitted through or reflected by a liquid sample by disposing the liquid sample in a path transmitting electromagnetic waves.
Conventionally, a spectroscopic device that measures characteristics of a material using electromagnetic waves such as ultraviolet rays, infrared rays, microwaves, and terahertz waves has been provided. Spectroscopy is classified into several methods according to the physical quantity measured by electromagnetic waves, but there are absorption spectroscopy and reflection spectroscopy among them. In the absorption spectroscopy, electromagnetic waves are transmitted through a sample corresponding to a spectroscopic measurement target and the physical or chemical property of the sample is measured from a change in electromagnetic wave caused by the interaction between the sample and the electromagnetic waves transmitted through the sample. Further, the reflection spectroscopy is used for spectroscopic measurement of a material that does not transmit light, a material that scatters light, or the like and measures the properties of the sample by observing the reflected light from the sample surface.
Light absorption of the material occurs when the photon energy matches the energy structure of the material. For this reason, it is necessary to select different light sources and measurement technologies according to the phenomenon or structure to be observed for the sample corresponding to the measurement target. In general, electromagnetic waves with short wavelengths (such as ultraviolet rays, infrared rays, and visible rays) are suitable for capturing small structures and strong interactions and electromagnetic waves with long wavelengths (such as terahertz waves) are suitable for capturing large structures and weak interactions. Terahertz time-domain spectroscopy (THz-TDS) is a spectroscopic method that obtains information on the amplitude and phase of a terahertz wave by Fourier-transforming a time waveform of an electromagnetic wave obtained by directly measuring the waveform of the terahertz wave.
A material to be used as a sample for spectroscopic measurement has various forms such as gas, solid, and liquid. A method of installing a material to be measured has been devised so that electromagnetic waves can be appropriately transmitted or reflected according to each form. For example, in order to perform highly accurate measurement on a liquid sample, the sample disposed in the spectroscopic device needs to be thin so that electromagnetic waves can be appropriately transmitted or reflected. Particularly when spectroscopically measuring a liquid sample such as an aqueous solution with terahertz waves, since the absorption effect of terahertz waves by water molecules is strong, it is necessary to make a liquid into a plate-shaped uniform thin film and transmit or reflect the terahertz waves to a plate-shaped portion for measurement in order to prevent deterioration of an SN ratio of a measurement signal.
In general, when measuring a liquid sample by absorption spectroscopy, the sample is sandwiched by a container (generally called a solution cell) formed of a material that transmits electromagnetic waves such as glass, the electromagnetic waves are incident from the outside of the solution cell, and the electromagnetic waves transmitted through the solution cell are measured. However, when the liquid sample is measured with the solution cell sandwiched therebetween, the spectral information of the cell material is superimposed on the spectral information of the liquid sample as noise and hinders the measurement of true spectral information.
Conventionally, in view of such a problem, a device capable of measuring spectral information with less noise without using a solution cell has been proposed (for example, see Patent Documents 1 to 3). In the device described in Patent Documents 1 to 3, a thin flat plate-shaped liquid film is generated by ejecting a liquid sample from a nozzle by a pressure of a pump using the nozzle that directly forms the liquid sample into a thin film.
Particularly, in order to solve a problem that when a liquid is pressurized by the pump and is ejected from the nozzle, the liquid scatters from an opening portion of the nozzle due to air bubbles contained in the ejected liquid, the liquid film generation device described in Patent Document 3 brings the liquid film generated by ejecting the liquid, which is sucked from a recovery tank by the pump and pressurized, from the nozzle into contact with a slope wall along the surface of the liquid film, and recovers and stores the liquid flowing down from the slope wall in the recovery tank.
However, the structure of Patent Document 3 described above is particularly effective when the liquid stored in the recovery tank is a liquid having no foamable property. In contrast, for example, when using a foamable solution such as a carbonated beverage containing carbon dioxide as a sample, since the solution itself originally contains a large amount of a gas, it is difficult to shape a thin film having a stable solution surface suitable enough for spectroscopic measurement even when the structure described in Patent Document 3 described above is used.
That is, when a foamable solution that dissolves a gas becomes a thin film by the method described in Patent Documents 1 to 3, air bubbles derived from a gas dissolved in the solution are generated from the inner wall of the container that holds the solution and the inner wall of the tube that carries the solution to the liquid film generation nozzle. Then, since the air bubbles flow into the liquid film generation nozzle, a turbulence of a flow occurs at a nozzle port and bumping or atomization of the solution occurs in the vicinity of a nozzle outlet. For that reason, it is not possible to obtain a thin film of which a surface of a liquid is flat and stable enough for spectroscopic measurement.
The invention has been made to solve such a problem and an object of the invention is to stably generate a thin and flat liquid film appropriately transmitting or reflecting electromagnetic waves even when a foamable solution is used as a sample of spectroscopic measurement.
In order to solve the above-described problems, the invention includes a nozzle section which ejects a liquid (which is foamable or not) and generates a plate-shaped liquid film having a flat surface in a space and a liquid leading section which leads the liquid to the nozzle section and an outermost portion of a liquid ejecting port corresponding to an opening ejecting a liquid in the nozzle section and an inner wall of the liquid leading section are disposed with a gap therebetween so as to satisfy a condition of a predetermined separation relationship.
A foamable solution that dissolves a gas is led from the liquid leading section toward the nozzle section and is ejected from the liquid ejecting port of the nozzle section so that a plate-shaped liquid film having a flat surface is generated in a space. At this time, gas molecules gather and grow into air bubbles due to the interaction between the inner wall of the liquid leading section and the foamable solution and the air bubbles adhere to the inner wall. The air bubbles adhering to the inner wall become larger by being combined with the surrounding air bubbles and move along the flow of the foamable solution. Here, the generation amount of the air bubbles becomes larger as it goes toward the inner wall and becomes smaller as it goes away from the inner wall. That is, it can be said that the bubbling of the foamable solution at the center portion of the liquid leading section is small.
In contrast, according to the invention with the above-described configuration, since a distance from the inner wall to the liquid ejecting port in the liquid leading section corresponding to the flow path immediately before the foamable solution reaches the nozzle section is increased, the foamable solution flowing in the vicinity of the center of the liquid leading section where the linear flow velocity of the liquid is the fastest and is less affected by the inner wall predominantly reaches the nozzle section. As described above, the foamable solution flowing in the vicinity of the center contains almost no air bubbles. Further, according to the structure of the invention, since the distance from the inner wall of the liquid leading section generating the air bubbles to the liquid ejecting port is increased, there is a high possibility that the air bubbles are absorbed into the foamable solution again while the air bubbles generated in the inner wall move to the liquid ejecting port of the nozzle section. Accordingly, it is possible to reduce the amount of the air bubbles entering from the liquid leading section into the nozzle section and to stably generate a thin and flat liquid film appropriately transmitting or reflecting electromagnetic waves even in the foamable solution. Note that, a thin and flat liquid film appropriately transmitting or reflecting electromagnetic waves can be stably generated since almost no air bubbles are originally contained in a solution when a liquid which is not foamable is used.
Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As illustrated in
As indicated by an arrow in
The pipe body constituting the nozzle section 10 is formed in a cylindrical shape. Similarly, the solution supply structure constituting the liquid leading section 20 is also formed in a cylindrical shape. A radius R10 of a circular cross-section of the nozzle section 10 is smaller than a radius R20 of a circular cross-section of the liquid leading section 20 (R10<R20). Note that, the shapes of the nozzle section 10 and the liquid leading section 20 may not be circular. For example, each of the nozzle section 10 and the liquid leading section 20 may be a tubular body having a polygonal cross-section.
The nozzle section 10 is disposed in the vicinity of the center of the cross-section perpendicular to a direction in which the foamable solution 100 flows through the liquid leading section 20 (preferably and accurately disposed at the center position). The connection between the nozzle section 10 and the liquid leading section 20 may be a connection while both portions are integrally formed with each other or may be a connection while the nozzle section 10 is attachable to or detachable from the liquid leading section 20.
An opening which communicates with the solution supply structure of the liquid leading section 20 is formed at one end of the pipe body constituting the nozzle section 10. This opening has a circular shape in which a radius is R10. Accordingly, the foamable solution 100 which flows through the liquid leading section 20 from the upper surface side to the bottom surface side is led from the opening toward the nozzle section 10.
A liquid ejecting port 11 which is smaller than the opening of one end is formed at the other end of the pipe body constituting the nozzle section 10. Accordingly, the foamable solution 100 which is led to the nozzle section 10 is ejected from the liquid ejecting port 11 toward the outside. The liquid ejecting port 11 is provided at the center position of the bottom surface of the nozzle section 10. The shape of the liquid ejecting port 11 is, for example, a square shape, but may be a rectangular shape. However, it is necessary to form the liquid ejecting port 11 in a shape in which an ejected liquid becomes a plate-shaped liquid film when a liquid is ejected from the liquid ejecting port 11.
As described above, since the liquid leading section 20 is a tubular body having a predetermined length D10, the foamable solution 100 flows therethrough almost linearly from the upper surface side toward the bottom surface side. The term “substantially linear” means that the foamable solution 100 does not flow linearly as a linear flow 101 parallel to the side surface of the liquid leading section 20 in all regions of the liquid leading section 20.
That is, the foamable solution 100 flowing in the vicinity of the center of the liquid leading section 20 flows toward the nozzle section 10 connected to the vicinity of the center of the liquid leading section 20 as the linear flow 101. In contrast, the foamable solution 100 flowing in the vicinity of the periphery of the liquid leading section 20 flows as a linear flow 102 directed from the vicinity of the periphery of the liquid leading section 20 toward the nozzle section 10 in the vicinity of the center as it goes toward the bottom surface of the liquid leading section 20.
The linear flow 101 flowing in the vicinity of the center of the liquid leading section 20 is hardly affected by an inner wall 21 of the liquid leading section 20 and the linear flow velocity becomes the fastest. For this reason, the foamable solution 100 which flows in the vicinity of the center of the liquid leading section 20 as the linear flow 101 predominantly reaches the nozzle section 10.
On the other hand, in a region near the inner wall 21 of the liquid leading section 20, gas molecules of the foamable solution 100 gather and grow into air bubbles 103 due to the interaction between the inner wall 21 and the foamable solution 100 flowing through the liquid leading section and the air bubbles 103 adhere to the inner wall 21. The air bubbles 103 adhering to the inner wall 21 become larger by being combined with the surrounding air bubbles 103 and move from the upper surface side toward the bottom surface side along the flow of the foamable solution 100. Here, the generation amount of the air bubbles 103 becomes larger as it goes toward the inner wall 21 and becomes smaller as it goes away from the inner wall 21. That is, it can be said that the bubbling of the foamable solution 100 at the center portion of the liquid leading section 20 is small.
In order to reduce the amount of the air bubbles 103 flowing into the liquid ejecting port 11 of the nozzle section 10, it is preferable that the liquid ejecting port 11 and the inner wall 21 of the liquid leading section 20 be separated from each other with a gap therebetween. Therefore, in this embodiment, the outermost portion of the liquid ejecting port 11 ejecting the foamable solution 100 in the nozzle section 10 and the inner wall 21 (side wall) of the liquid leading section are disposed with a gap therebetween so as to satisfy a condition of a predetermined separation relationship.
Specifically, a size of the liquid leading section 20 in one direction is set to be larger than a size of the liquid ejecting port 11 in one direction in order to satisfy a condition (corresponding to a first condition of claims) that a ratio between a size from the center of the liquid ejecting port 11 of the nozzle section 10 to the outermost portion in one direction perpendicular to the flow direction of the foamable solution 100 (a size from the center of the liquid ejecting port 11 to the outermost portion in a direction toward the outermost portion within a plane perpendicular to the flow direction of the foamable solution 100) and a size from the center of the liquid leading section 20 to the inner wall 21 in one direction (a size from the center of the liquid leading section 20 to the inner wall 21 in a direction toward the inner wall 21 within a plane perpendicular to the flow direction of the foamable solution 100) is larger than a predetermined ratio. Accordingly, the internal volume of the liquid leading section 20 leading the foamable solution 100 to the nozzle section 10 is increased.
For example, on the assumption that a length of one side of the square liquid ejecting port 11 is indicated by 2W11, a ratio with respect to a distance from the center (which is also the center of the liquid leading section 20) to the inner wall 21 of the liquid leading section 20 (a radius R20 of the liquid leading section 20) is “R20/W11>10”. In this case, a “size from the center of the liquid ejecting port 11 of the nozzle section 10 to the outermost portion in one direction perpendicular to the flow direction of the foamable solution 100” is W11 and a “size from the center of the liquid leading section 20 to the inner wall 21 in one direction” is R20. Note that, a “size from the center of the liquid ejecting port 11 of the nozzle section 10 to the outermost portion in one direction perpendicular to the flow direction of the foamable solution 100” is (long side length/2) if the liquid ejecting port 11 is a rectangular opening.
When the liquid film cartridge is configured in this way, a distance from the inner wall 21 to the liquid ejecting port 11 is increased in the liquid leading section 20 which is a flow path immediately before the foamable solution 100 reaches the nozzle section 10.
As described above, the foamable solution 100 flowing in the vicinity of the center of the liquid leading section 20 contains almost no air bubbles 103. Further, even when the foamable solution 100 flowing in the vicinity of the periphery of the liquid leading section 20 flows toward the nozzle section 10 in the vicinity of the center as it goes toward the bottom surface of the liquid leading section 20, there is a high possibility that the air bubbles 103 are absorbed into the foamable solution 100 again while the air bubbles 103 generated in the inner wall 21 move to the nozzle section 10 along the flow. Accordingly, it is possible to reduce the amount of the air bubbles 103 entering from the liquid leading section 20 into the nozzle section 10. As a result, it is possible to stably generate a thin and flat liquid film causing electromagnetic waves to be appropriately transmitted or reflected even when a liquid used as a sample is the foamable solution 100.
For example, when a length of one side of the liquid ejecting port 11 of the nozzle section 10 is set to 0.6 mm and an inner diameter of the liquid leading section 20 is set to be sufficiently larger than 6 mm, it is possible to suppress the air bubbles 103 generated in the inner wall 21 of the liquid leading section 20 from flowing into the nozzle section 10 and causing bumping at the liquid ejecting port 11 and to stably generate a thin and flat liquid film.
Note that, in order to further reduce the amount of the air bubbles 103 adhering to the inner wall 21 of the liquid leading section 20 and flowing into the liquid ejecting port 11 of the nozzle section 10, it is preferable that the length D10 of the nozzle section 10 be larger than the size W11 of the liquid ejecting port 11 in one direction so as to satisfy a condition that a ratio between the size Wn of the liquid ejecting port 11 of the nozzle section 10 in one direction and the size (the length (depth) D10 of the nozzle section 10) of the nozzle section 10 in a direction perpendicular to one direction is smaller than a predetermined ratio. For example, “D10/W11<20” is preferable.
In
When the opening portion of the liquid leading section 20 is directed upward while the nozzle attachment cap 30 is detached, the container of the liquid leading section 20 can be filled with the foamable solution 100. After filling the foamable solution 100 by an amount that the container is not full, the nozzle attachment cap 30 is attached and the top and bottom are inverted so that the nozzle attachment cap 30 faces downward (the direction of gravity). Accordingly, the foamable solution 100 is accumulated in a lower portion of the liquid leading section 20 below which the nozzle attachment cap 30 exists.
A through-hole is provided in the nozzle attachment cap 30 and a gas supply pipe 40 is inserted therethrough. The gas supply pipe 40 has a length in which a front end thereof reaches the vicinity of the closed opening portion (the bottom surface) of the liquid leading section 20 when the gas supply pipe is inserted into the liquid leading section 20. A compressed gas 200 can be sent from an external compressed gas supply device (not illustrated) into the liquid leading section 20 through the gas supply pipe 40. Due to the pressure of the compressed gas 200 sent to the liquid leading section 20, the foamable solution 100 stored in the liquid leading section 20 is led to the nozzle section 10 and the foamable solution 100 is ejected from the nozzle section 10 so that the liquid film 110 is generated.
In order to prevent this, the gas separation film 51 is disposed as a layer of a liquid film that is not combined with the foamable solution 100 and has a lower specific gravity than the foamable solution 100 at the interface between the foamable solution 100 stored in the liquid leading section 20 and the compressed gas 200 sent from the outside. Accordingly, it is possible to reduce the gas mixture into the foamable solution 100. A liquid used in the gas separation film 51 can be introduced into the liquid leading section 20 before the compressed gas 200 is sent using the gas supply pipe 40 sending the compressed gas 200.
Note that, here, an example in which the gas separation film 51 is disposed as a layer of the liquid film at the interface has been described here, but the invention is not limited thereto. For example, a film-shaped lid formed of a solid material that floats in the foamable solution 100 and is not combined with the foamable solution 100 may be disposed at the interface between the foamable solution 100 and the compressed gas 200, so that a ratio in which the compressed gas 200 is mixed into the foamable solution 100 can be reduced.
In the example illustrated in
Note that, air bubbles are generated until the pressurization foamable solution 100′ sent from the pressurization solution tank 53 to the liquid leading section 20 of the liquid film cartridge reaches the liquid leading section 20 through the liquid supply pipe 54. For that reason, the foamable solution 100′ is sent to the liquid leading section 20 while the air bubbles are mixed with the solution. However, the foamable solution 100′ containing the air bubbles is pressurized at a constant pressure and the foamable solution 100 which is stored in the liquid leading section 20 and is a measurement target can be sent to the nozzle section 10 by a suitable amount necessary for the measurement.
Here, the pressurization solution tank 53 and the compressed gas are used as a configuration for sending the pressurization foamable solution 100′ to the liquid leading section 20, but the invention is not limited thereto. For example, a syringe may be used instead of the pressurization solution tank 53 so that the foamable solution 100′ stored in the syringe is pressurized by a piston so that the foamable solution 100′ may be sent from the syringe to the liquid leading section 20 through the liquid supply pipe 54.
Further, the liquid leading section 20′ formed as a flexible container is disposed inside the pressurized gas container 61 which is not deformed even when a pressure caused by the compressed gas 200 is applied thereto. Then, when the compressed gas 200 is sent into the pressurized gas container 61, the liquid leading section 20′ is deformed by the pressure of the compressed gas 200, so that the foamable solution 100 stored inside the liquid leading section 20′ is sent to the nozzle section 10.
As described above in detail, the liquid film cartridge of this embodiment includes the nozzle section 10 which ejects the foamable solution 100 and generates the liquid film in a space and the liquid leading section 20 which leads the foamable solution 100 to the nozzle section 10 and the outermost portion of the liquid ejecting port 11 of the nozzle section 10 and the inner wall 21 of the liquid leading section 20 are disposed with a gap therebetween so as to satisfy the first condition.
According to this embodiment with such a configuration, since a distance from the inner wall 21 generating the air bubbles 103 to the liquid ejecting port 11 increases in the liquid leading section 20 which is the flow path immediately before the foamable solution 100 reaches the nozzle section 10, it is possible to reduce the amount of the air bubbles entering from the liquid leading section 20 into the nozzle section 10.
Accordingly, it is possible to stably generate a thin and flat liquid film appropriately transmitting or reflecting electromagnetic waves even when a liquid used as a sample is the foamable solution 100. As a result, it is possible to realize spectroscopic measurement in all wavelength regions where the characteristic data of the foamable solution has not been measured until now.
That is, if the liquid film generation device of this embodiment is used, it is possible to measure the liquid state at the molecular level of the foamable solution having a dissolved gas in real time according to the in-situ observation. As a result, it is possible to instantly measure a change in molecular bonding state in the foamable solution, a change in solution temperature due to temperature control, and the like. For example, it is possible to quickly and easily specify various conditions by changing manufacturing conditions such as an influence of gas molecules of sparkling beverages such as carbonated drinks and sparkling alcoholic beverages that have been difficult to measure on the taste and to largely contribute to industrial applications such as new product development and quality control.
The liquid film generation device of this embodiment can be widely applied to spectroscopic measurement using electromagnetic waves such as terahertz waves and infrared rays. That is, the liquid film generation device can be widely used for a spectroscopic device for obtaining information on intermolecular interactions in a solution, which is characterized by non-contact, non-destructive, non-invasive, and instantaneous measurement performance. Further, in the above-described embodiment, an example in which the liquid film 110 is generated from the foamable solution 100 has been described, but it goes without saying that a thin and flat liquid film can be stably generated from a liquid that does not have foamable property. This also applies to various modified examples described below.
Note that, in the above-described embodiment, the first condition has been described as the condition of the predetermined separation relationship which should be satisfied by the outermost portion of the liquid ejecting port 11 of the nozzle section 10 and the inner wall 21 of the liquid leading section, but the invention is not limited thereto. For example, as the condition of the predetermined separation relationship, a second condition in which a distance (R20−W11) between the outermost portion of the liquid ejecting port 11 of the nozzle section 10 and the inner wall 21 of the liquid leading section 20 is set to be larger than a predetermined value in any direction perpendicular to the flow direction of the foamable solution 100 may be used instead of or in addition to the first condition. As long as this condition is satisfied, the nozzle section 10 may be disposed at a position eccentrically located from the center of the bottom surface of the liquid leading section 20.
Alternatively, as the condition of the predetermined separation relationship, a third condition in which the inner wall 21 of the liquid leading section 20 is located further outside the outer periphery of the opening at one end side of the nozzle section 10 may be used instead of or in addition to the first condition. Note that, the configuration of the liquid film cartridge illustrated in
Further, in the above-described embodiment, a configuration example in which the liquid leading section 20 is configured as the container of the foamable solution 100 and the foamable solution 100 is led to the nozzle section 10 by an external pressure has been described, but the invention is not limited thereto. For example, as illustrated in
In the case of the configuration illustrated in
When the linear flow shaping pipe 20″ is used as the liquid leading section, means for leading the foamable solution 100 from the container 71 to the linear flow shaping pipe 20″ is not limited to the compressed gas illustrated in
Further, as illustrated in
Note that, in any method of
Further, in the above-described embodiment, a configuration example in which the nozzle section 10 and the liquid leading section 20 are connected to each other has been described, but the invention is not limited thereto. For example, as illustrated in
In the liquid film cartridge illustrated in
In addition, each of the above-described embodiments is merely an example of the embodiment when implementing the invention and the technical scope of the invention should not be limitedly interpreted thereby. That is, the invention can be implemented in various forms without departing from the spirit or the main features thereof.
For example, in the above-described embodiment, an example in which the liquid film cartridge is used so that the nozzle section 10 faces the lower side (the direction of gravity) and the foamable solution 100 is ejected downward to generate the liquid film 110 has been described, but the invention is not limited thereto. For example, as illustrated in
When the nozzle section 10 faces upward as illustrated in
Further, in the above-described embodiment, in order to suppress the generation of the air bubbles 103, a method of applying a coating that inhibits wettability to the surface of the inner wall 21 by applying a surfactant to the inner wall 21 of the liquid leading section 20 may be used together.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-038474 | Mar 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/001183 | 1/17/2019 | WO | 00 |
