JP2000193583A - Liquid cell for making sample liquid flaw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a liquid cell to have the function of preventing light from being irregularly reflected from the cell interface and to enable the optical path length to be lengthend even in a small space, by molding a pipe material of light transmitting material into a spiral shape or a waveform shape and adding a material of high light reflectance to the outer surface of the pipe material. SOLUTION: In cell holders 1 and 2, screw holes 3 and 4 open at different surface parts and flow channels 5 of a sample liquid are concentrically formed. The cell holders 1 and 2 are arranged on a base 7 via brackets 6 and 6 in such a way to bring the axes of the channels 5 and 5 into a concentric state. Then, an inflow channel 8 of a sample liquid connected to the channel 5 is formed in the one cell holder 1, and an outflow channel 9 of a sample liquid branched from the channel 5 is formed in the other cell holder 2. A pipe material 21 of light transmitting material is molded in a spiral shape or a waveform shape, and material 22 of high light reflectance is added to the outer surface of the pipe material 21 to constitute the liquid cell 19 for making a sample liquid flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid for distributing a sample liquid used for analysis of the concentration of silica contained in, for example, boiler water of a thermal power plant and ultrapure water used in the semiconductor industry and the like. It is about cells.

[0002]

2. Description of the Related Art Generally, analysis of silica concentration is carried out by making full use of an analysis method called a molybdenum yellow method utilizing a color reaction between a sample solution and a coloring reagent, and an analysis method called a molybdenum blue method. Regardless of which analysis method is adopted, an analyzer in which a liquid cell for measuring absorbance and an interference filter for flowing a sample liquid are arranged between a light source and a photodetector in this order is used. Can be

[0003] In this analyzer, the above color development is performed based on Lambert-Beer's law based on the intensity of light incident on the cell from the light source and the intensity of light transmitted through the cell and emitted to the photodetector. The output pattern of the photodetector obtained in the reaction process is analyzed, the absorbance of the sample solution is measured, and the silica concentration is analyzed based on the absorbance.In the molybdenum yellow method, sulfuric acid and molybdenum are added to the sample solution. An ammonium acid solution is injected to generate chromium molybdenum which has a yellow color, and the absorbance corresponding to a wavelength of, for example, around 400 nm can be measured from the chromium molybdenum yellow.

[0004] The analysis time during this period is 3 to 5 minutes, and a faster analysis is possible as compared with the molybdenum blue method described below.

[0005] On the other hand, in the molybdenum blue method, after the silica in the sample solution is reacted in the same configuration as the molybdenum yellow method, oxalic acid or ascorbic acid is injected as a reducing agent reagent to generate heteromolybdenum. hand,
From this heteromolybdenum blue, for example, 800 nm
The absorbance corresponding to a nearby wavelength can be measured.

[0006] The analysis time during this period is about 15 minutes, which is longer than the analysis time of the molybdenum yellow method, but can be analyzed within 5 minutes by setting the temperature of the sample solution to 40 to 50 ° C. The molybdenum blue method allows more accurate analysis than the molybdenum yellow method.

[0007]

Conventionally, as shown in FIG. 5, a liquid cell 33 for flowing a sample liquid disposed between a light source 31 and a photodetector 32 is used as a light-transmitting liquid cell. On the other hand, in order to prevent irregular reflection of light from the cell interface as much as possible, a condensing lens 34 is arranged at one end of the pipe-made cell 33 so that the light from the light source 31 becomes parallel light. Alternatively, the light beam diameter is reduced, and the light is made to enter the liquid cell 33. 35
Is an interference filter.

However, in these cases, there is a problem in that the adjustment of the optical system is difficult or a high-output light source 31 is required. In particular, when the optical path length of the cell 33 is increased, the problem becomes more remarkable. In addition, since the entire device becomes longer in proportion to the length of the optical path, there is a problem in that the installation space of the device is required to be large.

The present invention has been made in view of the above circumstances, and has as its object to provide a function of preventing irregular reflection of light from a cell interface and to increase an optical path length in a small space. It is an object of the present invention to provide a liquid cell for distributing a sample liquid, which enables the above.

[0010]

A liquid cell for flowing a sample liquid according to the present invention, which has achieved the above object, comprises forming a pipe material of a light-transmitting material into a spiral or corrugated shape, and It is characterized in that a material having high light reflectance is attached to the outer surface of the material.

[0011] According to the above-described structure, irregular reflection of light from the cell interface is prevented by attaching a material having a high light reflectance to the glass pipe material, and almost the entire amount of light is transmitted to the photodetector. Since the light arrives, the output of the light source can be reduced.

Further, by forming the pipe material into a spiral shape or a corrugated shape, a cell having a long optical path can be made small in space.
This can be made extremely narrow.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a silica analyzer, in which cell holders 1 and 2 are cell holders, and screw holes 3 and 4, which are opened on different surfaces, and a flow channel 5 for sample liquid, are formed concentrically. And the flow paths 5, 5
Are installed on the base 7 via the brackets 6 and 6 in a state where the axes of the axes are concentric.

A sample liquid inflow path 8 communicating with the flow path 5 is formed in one cell holder 1, and a sample liquid outflow path 9 branched from the flow path 5 is formed in the other cell holder 2.
Are formed.

As shown in FIG. 3, the bracket 6 includes a holder receiver 10 erected on the base 7 and a holding member 11 for the cell holders 1 and 2 mounted on the holder receiver 10. The two members 10 and 11 are configured to be screwed, for example.

Next, reference numerals 12 and 13 in the figure denote cell windows which are mounted in the screw holes 4 of the cell holders 1 and 2 so as to seal the flow path 5 via the screw members 14, respectively. Each of the screw members 14 has a through hole 15 concentric with the flow path 5, and the screw member 14 on one of the cell holders 1 is formed so as to face the through hole 15. Light source 1
6 and a screw member 14 on the other cell holder 2 side.
Includes an interference filter (or an LED or LD or the like that emits light near 400 nm) 17 that transmits only a desired wavelength band obtained in the color reaction step, and a photodetector 1.
8 are provided.

Reference numeral 19 denotes a liquid cell for flowing a sample liquid,
Both ends of the cell holders 1, 2 via the screw member 20
The cell holders 1 and 2 are connected to both ends of the liquid cell 17 with respect to the bracket 6, and the cell holders 1 and 2 are mounted on the holder receiver 10. And holding member 11 in holder holder 1
It is set by screwing it to 0.

As the liquid cell 19 for flowing the sample liquid,
In order to obtain a compact and long optical path length, for example, as shown in FIG.
1 is provided with a material 22 having a high light reflectance on the outer surface thereof, and the helical angle θ of the pipe material 21 is set to about 30 degrees, so that the light output from the light source 16 has a high light reflectance. Consideration is given so that the material surface is smoothly reflected and reaches the photodetector 18.

In the analysis of the silica concentration by the above-mentioned silica analyzer, when the molybdenum yellow method is used,
An interference filter that transmits a wavelength around 00 nm (or an LED or LD that emits light around 400 nm) 17
And a sulfuric acid and ammonium molybdate solution are injected into the sample solution as reagents,
While irradiating light from the light source 16 toward the photodetector 18 to generate chromium molybdenum colored yellow, and based on the analysis of the output pattern from the photodetector 18, the The absorbance corresponding to a wavelength around 400 nm is measured, and the silica concentration is analyzed based on the absorbance.

When using the molybdenum blue method, 800
interference filter (or 8
Hetero molybdenum is generated by using oxalic acid or ascorbic acid as a reagent by using an LED or an LD 17 that emits light having a wavelength of about 00 nm, and a wavelength of about 800 nm from the blue of the hetero molybdenum. By measuring the absorbance corresponding to the above, the silica concentration is analyzed.

Here, originally, a condensing lens is arranged between the light source 16 and the liquid cell 19, and the light from the light source 16 is collimated or the light beam diameter is reduced, so that the light from the cell interface is reduced. Although it was necessary to prevent diffused reflection of light, in the liquid cell 19 according to the present invention, the material 22 having high light reflectance prevented diffused reflection of light from the cell interface, and almost completely blocked the light from the light source 16. Since the entire amount can be emitted to the photodetector 18,
In particular, no condensing lens is provided. In this case, it is important to arrange the light source 16 as close as possible to the liquid cell 19 so that all the light output from the light source 16 is introduced into the liquid cell 19. It is.

Even when a condenser lens is not provided, it is preferable to dispose a slit in the vicinity of the light source 16, and in any case, simplification of the condenser system can be achieved. It goes without saying that a lens may be provided.

In the liquid cell 19, it is optimal to form the pipe material 21 in a spiral shape in order to lengthen the optical path length in a small space. However, as shown in FIG. It is needless to say that the optical path length can be lengthened even if it is formed, and a hollow optical fiber or the like is suitably selected as the material of the pipe material 21 in addition to, for example, sodium glass, quartz glass, and lead glass.

The material 22 having a high light reflectivity is preferably Au or C having a reflectivity in the infrared region of 95% or more.
A material having a high reflectivity with respect to light of a desired wavelength, such as u or Al, may be selected and coated. For example, an aluminum foil is wound around the outer surface of the pipe material 21. It may take the form.

[0025]

As described above, according to the liquid cell for flowing sample liquid according to the present invention, irregular reflection of light from the cell interface is prevented, and almost all of the light output from the light source is obtained. Reaches the photodetector, it is possible to reduce the output of the liquid cell as a light source of the device equipped with the liquid cell, and further, since the optical path has a spiral or wavy shape, the optical path length is long. The cell can be obtained in a small space, and as a device including the liquid cell, the installation space for the cell can be made extremely narrow as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a silica analyzer.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory view showing a holding bracket of a cell holder.

FIG. 4 is a configuration diagram of a silica analyzer provided with a liquid cell according to another embodiment.

FIG. 5 is a schematic configuration diagram of a conventional silica analyzer.

[Explanation of symbols]

16 ... light source, 18 ... photodetector, 19 ... liquid cell, 21 ...
Pipe material, 22: Material with high light reflectance.

Claims (1)

[Claims] 1. A liquid cell for flowing sample liquid, which receives light from a light source from one end side and emits the light to a photodetector on the other end side, wherein a pipe material of a light-transmitting material is formed in a spiral or wave shape. A liquid cell for flowing a sample liquid, characterized in that the liquid material is formed by molding a material having a high light reflectance on the outer surface of the pipe material.