A lower critical temperature indicating device

Abstract

The present invention provides a lower critical temperature indicator device, comprising a housing assembly and an indicator assembly. The housing assembly defines a first cavity; the indicator assembly is disposed within the first cavity. The indicator assembly includes a container, a first medium, a second medium, and an indicator. The container defines a second cavity, and the first and second media are stacked within the second cavity. The first and second media are mutually immiscible. When the first medium is liquid, the indicator is below the interface of the first medium, and no indication reaction occurs between the indicator and the second medium. When the first medium is solid, the indicator is at least partially above the interface of the first medium, and in this case, an indication reaction occurs between the indicator and the second medium. With this lower critical temperature indicator device, a user can intuitively determine whether the ambient temperature has exceeded the lower critical threshold by observing the indication reaction.

Description

Technical Field

[0001] The present invention relates to the field of indication technology, in particular to a lower critical temperature indicating device. Background Art

[0002] Biological products such as plasma and vaccines need to be stored in a low-temperature environment of 2-8 degrees Celsius. When the ambient temperature exceeds the above temperature threshold, the biological products will deteriorate rapidly, especially when the ambient temperature is below the lower critical temperature threshold, the biological products will quickly lose their activity due to overcooling.

[0003] At present, there are many temperature indicating devices for indicating the upper critical temperature in the existing technology, but the lower critical temperature is mainly monitored by electronic devices. This monitoring method is relatively expensive, cannot monitor a single packaging box, and there is a possibility of data tampering. Therefore, it is necessary to provide a low-cost lower critical temperature indicating device to monitor the lower critical temperature of the cold chain. Summary of the Invention

[0004] The present invention provides a lower critical temperature indicating device for indicating whether the cold chain temperature exceeds a lower critical threshold.

[0005] A lower critical temperature indicating device, comprising:

[0006] A housing assembly having a first cavity therein;

[0007] An indicator assembly is disposed in the first cavity, comprising a container, a first medium, a second medium, and an indicator. A second cavity is disposed in the container, and the first medium and the second medium are stacked in the second cavity. The first medium and the second medium are mutually immiscible, and the first medium has both liquid and solid forms. When the first medium is in liquid form, the indicator is located below the interface of the first medium. When the first medium is in solid form, the indicator is at least partially located above the interface of the first medium and in contact with the second medium. At this time, the indicator can produce an indication reaction with the second medium.

[0008] In one embodiment, the first medium is a lipid substance.

[0009] In one embodiment, the first medium is selected from at least one of linolenic acid, ethyl oleate, dodecane, diethyl maleate, linoleic acid, palmitoleic acid, triacetin, diethyl sebacate, n-butyl myristate, methyl laurate, n-tetradecane, n-decanol, oleyl alcohol, isopropyl myristate, pentadecane, ethyl myristate, oleic acid, nonanoic acid, octanoic acid, isooctyl octanoate, methyl myristate, hexadecane, heptadecane, lauryl alcohol, and ethyl palmitate.

[0010] In one embodiment, the second medium is an aqueous solution or an oxygen-containing gas.

[0011] In one embodiment, the indicator reaction is a change in volume morphology.

[0012] In one embodiment, the volume change is specifically adsorption expansion.

[0013] In one embodiment, the volume morphology change is dissolution.

[0014] In one embodiment, the indicator reaction is a chemical reaction.

[0015] In one embodiment, the chemical reaction is a chelation reaction.

[0016] In one embodiment, the chemical reaction is a redox reaction.

[0017] In the above-mentioned lower critical temperature indicating device, when the first medium is in liquid form, the indicator is below the interface of the first medium and does not contact the second medium. Therefore, no indication reaction occurs between the indicator and the second medium. When the first medium changes from liquid form to solid form, the volume of the first medium decreases and the interface is lowered, causing the indicator to be at least partially above the interface of the first medium, so that the indicator contacts the second medium, thereby causing an indication reaction between the indicator and the second medium. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold through the indication reaction.

[0018] The beneficial effects of the above-mentioned lower critical temperature indicating device include: (1) the lower critical temperature threshold is determined by the freezing point of the first medium, which is convenient for adjustment; (2) the indicated reaction result is irreversible and the indication is accurate; (3) the indicating device has a simple structure and low cost; (4) the indicating device is small in size and can monitor a single packaging box. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a lower critical temperature indicating device at normal temperature according to one embodiment;

[0020] Figure 2 For example Figure 1 A schematic diagram of the lower critical temperature indicating device shown when the temperature is below the lower critical temperature;

[0021] Figure 3 For example Figure 2 Schematic diagram of the indication effect of the lower critical temperature indicating device shown;

[0022] Figure 4 is a schematic diagram of a lower critical temperature indicating device according to another embodiment at normal temperature;

[0023] Figure 5 For example Figure 4 A schematic diagram of the lower critical temperature indicating device shown when the temperature is below the lower critical temperature;

[0024] Figure 6 For example Figure 5 Schematic diagram of the indication effect of the lower critical temperature indicating device shown;

[0025] Figure 7 is a schematic diagram of a lower critical temperature indicating device according to another embodiment at normal temperature;

[0026] Figure 8 For example Figure 7 A schematic diagram of the lower critical temperature indicating device shown when the temperature is below the lower critical temperature;

[0027] Figure 9 For example Figure 8 Schematic diagram of the indication effect of the lower critical temperature indicating device shown;

[0028] Figure 10 is a schematic diagram of a lower critical temperature indicating device according to another embodiment at normal temperature;

[0029] Figure 11 For example Figure 10 A schematic diagram of the lower critical temperature indicating device shown when the temperature is below the lower critical temperature;

[0030] Figure 12 For example Figure 11 Schematic diagram of the indication effect of the critical temperature indicating device shown. DETAILED DESCRIPTION

[0031] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected" or "communicating" with another element, it may be directly connected to the other element or there may be an intermediate element. The terms "upper," "lower," "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0033] The lower critical temperature indicating device will be further described in detail below mainly with reference to the accompanying drawings and specific embodiments.

[0034] See also Figures 1 to 3 A lower critical temperature indicating device according to one embodiment includes a housing assembly 10 and an indicating assembly 20 .

[0035] The housing assembly 10 includes a front housing 11 and a rear housing 12 . A first cavity is defined in the housing assembly 10 .

[0036] Specifically, the front housing 11 is made of a transparent material. The side of the front housing 11 facing the rear housing 12 is partially recessed inward to form a groove, while the side of the front housing 11 facing away from the rear housing 12 is partially convex forward to form an observation window. The rear housing 12 is used to close the opening of the groove, thereby forming a first cavity in the housing assembly 10, which is used to accommodate the indicator assembly 20.

[0037] Optionally, materials used to prepare the front housing 11 include, but are not limited to, PET, PVC, acrylic, and glass.

[0038] The indicator assembly 20 is disposed in the first cavity. The indicator assembly 20 further includes a container 21 , a first medium 22 , a second medium 23 and an indicator 24 .

[0039] The container 21 has a second cavity therein and is made of a transparent material so that a user can observe through the container 21 whether the indicator 24 has generated an indication reaction.

[0040] Preferably, the inner diameter of the second cavity is 1 mm to 5 mm. By limiting the inner diameter of the second cavity, the first medium 22 and the second medium 23 can be fixed in the second cavity by surface tension, thereby preventing the interface of the first medium 22 from changing under the action of gravity when the indicator device is placed in a non-vertical state, thereby preventing the indicator device from being mistakenly activated.

[0041] Preferably, the inner diameter of the second cavity is 2 mm-3 mm. The second cavity with an inner diameter within this range can facilitate the placement of the first medium 22, the second medium 23 and the indicator 24 while preventing changes in the interface of the first medium 22 in a non-vertical state.

[0042] Optionally, materials used to prepare the container 21 include, but are not limited to, PET, PVC, acrylic, and glass.

[0043] The first medium 22 is provided at the bottom of the second cavity and has two forms, liquid and solid. In the lower critical temperature indicator device, the first medium 22 plays two roles: (1) It plays a role in exciting the lower critical temperature. When the ambient temperature is higher than the melting point of the first medium 22, the first medium 22 is in liquid form. When the ambient temperature is lower than the solidification point of the first medium 22, the first medium 22 is in solid form. In the process of the first medium 22 changing from liquid form to solid form, its volume is reduced, which leads to the lowering of the interface of the first medium 22, triggering the indication reaction. Therefore, its solidification temperature can be used as the excitation temperature of the lower critical temperature indicator device. (2) It plays a role in protecting the indicator 24. The first medium 22 and the indicator 24 do not react with each other. When the first medium 22 is in liquid form, the indicator 24 located below the interface of the first medium 22 is in a protected state, which can prevent the indicator 24 from contacting the second medium 23.

[0044] Specifically, the first medium 22 is an oily material having a specific freezing point and is incompatible with the aqueous second medium 23 .

[0045] Furthermore, the first medium 22 is a lipid substance. As a type of oily material, lipid substances are common chemical materials, easy to obtain and inexpensive. More importantly, pure lipid substances have a specific freezing point. In order to obtain the first medium 22 with a specific freezing point, two lipid substances with different freezing points can be mixed to make the first medium 22 more convenient to obtain.

[0046] Optionally, the first medium 22 includes but is not limited to: at least one of linolenic acid, ethyl oleate, dodecane, diethyl maleate, linoleic acid, palmitoleic acid, triacetin, diethyl sebacate, n-butyl myristate, methyl laurate, n-tetradecane, n-decanol, oleyl alcohol, isopropyl myristate, pentadecane, ethyl myristate, oleic acid, nonanoic acid, octanoic acid, isooctyl octanoate, methyl myristate, hexadecane, heptadecane, lauryl alcohol, and ethyl palmitate.

[0047] The second medium 23 is stacked on the first medium 22 . The second medium 23 and the first medium 22 are incompatible with each other, and the second medium 23 can react with the indicator 24 to generate an indication reaction.

[0048] In this embodiment, the second medium 23 is an aqueous solution that is immiscible with the oily first medium 22 , thereby ensuring that when the first medium 22 is in liquid form, the second medium 23 will not come into contact with the indicator 24 in the first medium 22 .

[0049] Specifically, the second medium 23 can be pure water or an aqueous solution containing antifreeze. By dissolving the antifreeze in water, the freezing point of the second medium 23 can be lowered, thereby ensuring that when the first medium 22 changes from liquid to solid, the second medium 23 remains in liquid form, thereby ensuring that the second medium 23 can contact the indicator 24 when the interface of the first medium 22 changes.

[0050] Optionally, the antifreeze includes but is not limited to: methanol, ethanol, isopropanol, ethylene glycol, propylene glycol, diethylene glycol, ethylene glycol butyl ether, propylene glycol butyl ether, ethylene glycol butyl ether acetate, dichloromethane, 1,1-dichloroethane, 1,2-dichloroethane, dimethyl sulfoxide, formamide, calcium chloride, sodium acetate, magnesium chloride, sodium chloride, and potassium chloride.

[0051] In another embodiment, the second medium 23 is a gas, which will not dissolve in the first medium 22 but can react with the indicator 24 to produce an indication reaction.

[0052] Optionally, the second medium 23 is an oxygen-containing gas. Oxygen, as an active gas, can undergo an oxidation-reduction reaction with the indicator 24 .

[0053] The indicator 24 has an oleophobic outer surface and is disposed in the first medium 22 and near the interface of the first medium 22 , thereby ensuring that when the first medium 22 is in liquid form, the indicator 24 is completely covered by the first medium 22 and does not come into contact with the second medium 23 .

[0054] Specifically, indicator 24 is positioned 1 mm to 5 mm below the interface of first medium 22. When first medium 22 changes from liquid to solid, the interface height of first medium 22 typically decreases by 2 mm to 6 mm. As the interface of first medium 22 decreases, indicator 24 is at least partially exposed above the interface of first medium 22. The oleophobic outer surface prevents first medium 22 from adhering to the surface of indicator 24 to form a barrier layer, thereby ensuring that indicator 24 can contact second medium 23. Once indicator 24 contacts second medium 23, an indicator reaction occurs with second medium 23. This indicator reaction can be a physical change or a chemical reaction.

[0055] In this implementation, see Figure 1-Figure 3 The indicator reaction is a change in physical form, which is manifested as a change in volume of the indicator 24. Specifically, the indicator 24 is a water-absorbing material that can absorb the second medium 23 and cause the physical form of the indicator 24 to change.

[0056] Optionally, the water-absorbing material is a water-absorbing and expanding material. After the water-absorbing and expanding material absorbs water, the volume of the second medium 23 decreases. At the same time, the volume of the indicator 24 expands, and the change in physical form is irreversible. Therefore, the user can judge whether the cold chain temperature exceeds the lower critical temperature by the volume change of the indicator 24 or the second medium 23.

[0057] Optionally, the water-swellable material includes but is not limited to sodium polyacrylate and expandable rubber.

[0058] It should be understood that the change in physical form may also be that the color of the indicator 24 itself changes after the indicator 24 absorbs the colored second medium 23 .

[0059] In another embodiment, see Figure 4-Figure 6 The indicator reaction is a physical change, manifested as the dissolution of indicator 24. Specifically, indicator 24 is a hydrophilic solute that dissolves in second medium 23. When the solute dissolves, indicator 24 disappears. Preferably, indicator 24 is a colored substance, and when indicator 24 dissolves, the color of second medium 23 changes. Therefore, the user can determine whether the cold chain temperature has exceeded the lower critical temperature by the presence of indicator 24 or the color change of second medium 23.

[0060] Optionally, the solute includes but is not limited to: sodium chloride crystals, sucrose crystals, potassium permanganate crystals, polyacrylamide, tetraamminecopper sulfate, and polyferric sulfate.

[0061] In another embodiment, see Figure 7-Figure 9 The indicating reaction is a chemical reaction. When the indicator 24 contacts the second medium 23, the indicator 24 and the second medium 23 undergo a chemical reaction. Optional chemical reactions include but are not limited to chelating reactions.

[0062] Specifically, the indicator 24 is a core-shell structure, the outer shell is made of a water-soluble material, and a chelating agent is provided inside. The second medium 23 contains specific ions. When the water-soluble outer shell is dissolved, the chelating agent reacts with the specific ions in the second medium 23 and undergoes a significant color change. Therefore, the user can judge whether the cold chain temperature exceeds the lower critical temperature by the color change of the second medium 23.

[0063] Optionally, the water-soluble material includes but is not limited to polyacrylamide.

[0064] Optionally, the chelating agent includes, but is not limited to, ethylenediamine (EN), bidentate 2,2'-bipyridine (BIPY), bidentate 1,10-phenanthroline (Phen), bidentate oxalate (OX), and bidentate ethylenediaminetetraacetic acid (EDTA).

[0065] Optionally, the specific ion is a metal ion.

[0066] In another embodiment, please participate in Figure 10-12 The indicating reaction is a chemical reaction. When the indicator 24 contacts the second medium 23 , the indicator 24 and the second medium 23 undergo a chemical reaction. Specifically, the chemical reaction is an oxidation-reduction reaction.

[0067] Specifically, the indicator 24 contains a reducing agent, and the second medium 23 is an oxygen-containing gas. When the indicator 24 comes into contact with the second medium 23, an oxidation-reduction reaction can occur in the indicator 24. During the reaction, the color of the indicator changes. Therefore, the user can judge whether the cold chain temperature exceeds the lower critical temperature by the color change of the indicator 24.

[0068] Optionally, the reducing agent includes but is not limited to ferrous hydroxide.

[0069] Preferably, the indicator 24 is provided in a film-like form on a side of the second cavity away from the rear housing 12 . This arrangement helps the user to clearly see whether the color or shape of the indicator 24 has changed.

[0070] exist Figure 10-12 In the embodiment shown, an adhesive layer 30 is further provided on the side of the rear shell 12 away from the front shell 11, and a release layer 40 is further provided on the side of the adhesive layer 30 away from the rear shell 12. By providing the adhesive layer 30, the lower critical indicator device can be conveniently attached to the surface of an object, and by providing the release layer 40, it is used to protect the adhesive layer 30.

[0071] In the above-mentioned lower critical temperature indicating device, when the first medium 22 is in liquid form, the indicator 24 is below the interface of the first medium 22 and is not in contact with the second medium 23. Therefore, no indication reaction occurs between the indicator 24 and the second medium 23. When the first medium 22 changes from liquid form to solid form, the volume of the first medium 22 decreases and the interface is lowered, causing the indicator 24 to be at least partially above the interface of the first medium 22, so that the indicator 24 contacts the second medium 23, thereby causing the indicator 24 to have an indication reaction with the second medium 23. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold through the indication reaction.

[0072] The beneficial effects of the above-mentioned lower critical temperature indicating device include: (1) the lower critical temperature threshold is determined by the freezing point of the first medium 22, which is convenient for adjustment; (2) the indicating reaction result is irreversible and the indication is accurate; (3) the indicating device has a simple structure and low cost; (4) the indicating device is small in size and can monitor a single packaging box.

[0073] The following are specific examples. Example

[0074] See also Figure 1-Figure 3 This embodiment provides a lower critical temperature indicating device, including a housing assembly 10 and an indicating assembly 20 .

[0075] The housing assembly 10 includes a front housing 11 and a rear housing 12. The front housing 11 is made of PVC. A first cavity is defined within the housing assembly 10, and an indicator assembly 20 is disposed within the first cavity. The indicator assembly 20 includes a container 21, a first medium 22, a second medium 23, and an indicator 24. The container 21 is made of acrylic and defines a second cavity with a diameter of 2 mm. The first and second mediums 22, 23 are stacked within the second cavity, and the indicator 24 is disposed within the first medium 22 near its interface. In this embodiment, the first medium 22 is palmitoleic acid, which has a freezing point of 0°C, and the second medium 23 is saline. The indicator 24 is a water-absorbing resin, sodium polyacrylate, and is disposed 1 mm below the liquid level of the first medium 22.

[0076] In the above-mentioned lower critical temperature indicating device, when the ambient temperature is higher than 0°C, the first medium 22 is in liquid form. At this time, the indicator 24 is below the interface of the first medium 22 and is not in contact with the second medium 23. Therefore, the indicator 24 and the second medium 23 do not produce an indication reaction. When the ambient temperature is lower than 0°C, the first medium 22 changes from liquid form to solid form. At this time, the volume of the first medium 22 decreases and the interface is lowered, causing the indicator 24 to be at least partially above the interface of the first medium 22, so that the indicator 24 contacts the second medium 23, thereby causing the indicator 24 to produce an indication reaction with the second medium 23 and expand in volume. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold by the indication reaction.

[0077] The beneficial effects of the above-mentioned lower critical temperature indicating device include: (1) the lower critical temperature threshold is determined by the freezing point of the first medium 22, which is convenient for adjustment; (2) the indicating reaction result is irreversible and the indication is accurate; (3) the indicating device has a simple structure and low cost; (4) the indicating device is small in size and can monitor a single packaging box. Example

[0078] See also Figures 4 to 6 The lower critical temperature indicating device provided in this embodiment is similar to the lower critical temperature indicating device provided in Example 1, except that: (1) the diameter of the second cavity is 3 mm; (2) the first medium 22 is triacetin, which has a freezing point of 3°C; (3) the second medium 23 is an aqueous solution containing ethanol; and (4) the indicator 24 is potassium permanganate crystals.

[0079] In the above-mentioned lower critical temperature indicating device, when the ambient temperature is higher than 3°C, the first medium 22 is in liquid form. At this time, the indicator 24 is below the interface of the first medium 22 and is not in contact with the second medium 23. Therefore, the indicator 24 and the second medium 23 do not produce an indication reaction. When the ambient temperature is lower than 3°C, the first medium 22 changes from liquid form to solid form. At this time, the volume of the first medium 22 decreases and the interface is lowered, causing the indicator 24 to be at least partially above the interface of the first medium 22, so that the indicator 24 contacts the second medium 23, which in turn causes the indicator 24 and the second medium 23 to produce an indication reaction. Potassium permanganate dissolves in the second medium 23, causing the second medium 23 to appear purple. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold by the indication reaction. Example

[0080] See also Figures 7 to 9 The lower critical temperature indicating device provided in this embodiment is similar to the lower critical temperature indicating device provided in Example 1, except that: (1) the diameter of the second cavity is 4 mm; (2) the first medium 22 is n-butyl myristate, and the freezing point is 5°C; (3) the second medium 23 is an aqueous solution containing iron ions; and (4) the indicator 24 is a core-shell structure, the outer shell is made of water-soluble polyacrylamide, and the inner shell is provided with o-phenanthroline powder.

[0081] In the above-mentioned lower critical temperature indicating device, when the ambient temperature is higher than 5°C, the first medium 22 is in liquid form. At this time, the indicator 24 is below the interface of the first medium 22 and is not in contact with the second medium 23. Therefore, the indicator 24 and the second medium 23 will not produce an indication reaction. When the ambient temperature is lower than 5°C, the first medium 22 changes from liquid form to solid form. At this time, the volume of the first medium 22 decreases and the interface is lowered, causing the indicator 24 to be at least partially above the interface of the first medium 22, so that the indicator 24 is in contact with the second medium 23. When the shell material dissolves, o-phenanthroline reacts with the iron ions in the second medium 23 to chelate, causing the second medium 23 to appear red. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold through the indication reaction. Example

[0082] See also Figures 10 to 12 The lower critical temperature indicating device provided in this embodiment is similar to the lower critical temperature indicating device provided in Example 1, except that: (1) the first medium 22 is a mixture of linoleic acid and oleyl alcohol, and the freezing point is 2°C; (2) the second medium 23 is a gas containing oxygen; and (3) the indicator 24 is a film layer containing ferrous hydroxide.

[0083] In the above-mentioned lower critical temperature indicating device, when the ambient temperature is higher than 2°C, the first medium 22 is in liquid form. At this time, the indicator 24 is below the interface of the first medium 22 and is not in contact with the second medium 23. Therefore, the indicator 24 and the second medium 23 do not produce an indication reaction. When the ambient temperature is lower than 2°C, the first medium 22 changes from liquid form to solid form. At this time, the volume of the first medium 22 decreases and the interface is lowered, causing the indicator 24 to be at least partially above the interface of the first medium 22, so that the indicator 24 is in contact with the second medium 23. The ferrous hydroxide in the indicator 24 easily undergoes an oxidation-reduction reaction with the oxygen in the second medium 23, causing the ferrous oxide to be oxidized into red ferric oxide. Therefore, the user can intuitively judge whether the ambient temperature exceeds the lower critical threshold through the indication reaction.

[0084] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A lower critical temperature indicating device, characterized in that: include: a housing assembly having a first cavity therein; The indicator assembly is disposed in the first cavity, comprising a container, a first medium, a second medium, and an indicator. The container is provided with a second cavity, and the first medium and the second medium are stacked in the second cavity. The first medium and the second medium are mutually immiscible. The first medium is an oily material and has both liquid and solid forms. When the first medium is in a liquid form, the indicator is located 1 mm to 5 mm below the interface of the first medium and does not contact the second medium. When the first medium is in a solid form, the indicator is at least partially located above the interface of the first medium and in contact with the second medium. At this time, the indicator and the second medium produce an indication reaction.

2. The lower critical temperature indicating device according to claim 1, characterized in that: The first medium is a lipid substance.

3. The lower critical temperature indicating device according to claim 2, characterized in that: The first medium is selected from at least one of linolenic acid, ethyl oleate, dodecane, diethyl maleate, linoleic acid, palmitoleic acid, triacetin, diethyl sebacate, n-butyl myristate, methyl laurate, n-tetradecane, n-decanol, oleyl alcohol, isopropyl myristate, pentadecane, ethyl myristate, oleic acid, nonanoic acid, octanoic acid, isooctyl octanoate, methyl myristate, hexadecane, heptadecane, lauryl alcohol, and ethyl palmitate.

4. The lower critical temperature indicating device according to claim 1, characterized in that: The second medium is an aqueous solution or an oxygen-containing gas.

5. The lower critical temperature indicating device according to claim 4, characterized in that: The indicator reaction is a change in volume and form.

6. The lower critical temperature indicating device according to claim 5, characterized in that: The change in volume and shape is specifically adsorption expansion.

7. The lower critical temperature indicating device according to claim 5, characterized in that: The change in volume and form is specifically dissolution.

8. The lower critical temperature indicating device according to claim 4, characterized in that: The indicator reaction is a chemical reaction.

9. The lower critical temperature indicating device according to claim 8, characterized in that: The chemical reaction is a chelation reaction.

10. The lower critical temperature indicating device according to claim 8, characterized in that: The chemical reaction is an oxidation-reduction reaction.

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