JPH02232586A - Measurement of integrated global solar radiation using pigment measuring plate - Google Patents

Abstract

PURPOSE:To enable measurement of an integrated global solar radiation value from a fading rate of a pigment measuring plate by using the measuring plate coated or impregnated with a pigment which is faded or discolored at a rate of 5-8% by sunshine. CONSTITUTION:A measuring plate is coated or impregnated with a pigment insoluble to water to calculate a global solar radiation from a fading rate of the pigment by sunshine. The pigment herein effective is an azo pigment such as Sudan I or Sudan IV. Triphenyl methane based pigment, guinoid based pigment and the like can be used as such because they provides a proper solubility and discoloring. The measuring plate having a pigment immobilized by coating or impregnation measures an optical density of the pigment beforehand and compares with an optical density obtained after exposure thereof to solar radiation to calculate a fading rate. This enables measurement of an amount of solar radiation received by a plant, a change in the amount of solar radiation received by a building and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Purpose of the invention Field of application The present invention is an integrated solar radiation measurement method that enables simultaneous multi-point integrated measurement of global solar radiation at low cost and ease. It can be used for changing the amount of solar radiation caused by objects and for other simple measurements of the amount of solar radiation. Conventional technology Traditionally, most methods of measuring global solar radiation have used expensive measuring equipment, and it is difficult to integrate and measure global solar radiation over a single day or several tens of days. was extremely difficult. In addition, since measurements at multiple points are impossible with a limited number of devices, most of the measurements have been based on instantaneous values. Problems to be Solved by the Invention In the present invention, (1) the material is easy to manufacture and inexpensive; (2) Simultaneous, multi-point measurements are possible. (3) It is not affected by rain, etc., and therefore it is possible to measure underwater. (4) We tried to solve problems such as ensuring reproducibility and high accuracy for practical use. For example, estimation calculations are the only way to measure solar radiation on the leaves of plants without damaging them, to compare the amount of solar radiation depending on the direction of the plant's leaves, and to measure differences in the amount of solar radiation depending on the shape of the plant. ．． Furthermore, in the case of long-term measurements, it was often difficult to carry out measurements because it was necessary to consider the possibility of equipment damage due to rainy weather. For example, it is extremely important to measure seasonal changes in solar radiation above and below the trees at multiple points over a long period of time in a forest area, but this requires a large number of expensive measuring instruments. It was impossible to keep it installed in such a place for a long period of time. (2) Means for solving the structural problems of the invention In order to solve the above problems, a water-insoluble pigment is coated or impregnated on the measuring plate, and the total solar radiation is measured based on the fading rate of this pigment due to solar radiation. We decided to calculate. As a pigment,
Azo dyes such as Sudan ■, Sudan ■, Oil Red 0, pyridylazo-2-naphthol (hereinafter referred to as PAN) were particularly effective, but triphenylmethane dyes, quinoid dyes, etc. also have appropriate solubility. Dyes that showed moderate fading or discoloration could be used. The optical density of the dye is measured in advance on the measuring plate that has been coated or impregnated with the dye, and the rate of fading or discoloration is calculated by comparing the optical density with the optical density after exposure to sunlight. Optical density is most accurately measured at the wavelength of maximum absorption using a self-recording spectrophotometer. The size of the measurement plate is determined by the optical density measuring instrument, but when using an ordinary self-recording spectrophotometer, the size of the measurement plate is 12 to 13 cm in width and 35 to 35 cm in length.
40aa is enough. To measure the total solar radiation amount based on the fading rate or discoloration rate of the action measurement plate, you can use a pre-measured calibration curve or create an approximation formula for the calibration curve in advance. When measuring the total solar radiation from the fading rate or discoloration rate of the measurement plate, more accurate measurements can be made by correcting the temperature at the time of fading or by using a correction calibration curve for each temperature. Example 1 A method for impregnating a film with a dye is to dissolve the dye in acetone and bring it into contact with the liquid surface of a triacetyl cellulose film, which is a type of measurement plate, for a certain period of time to create an impregnated film with a dye layer of a certain thickness. Manufacture. In this case, it is convenient to set the transmission density of the film to around 2 at the maximum absorption wavelength of the dye. Sudan■, Sudan■ are soluble in A7T and have a film density of around 2. Oil Red 0, PAN, etc. were selected. In addition to acetone, methyl ethyl ketone or a mixture of acetone can be used as a solvent to be used.
A small amount of another solvent can also be added. Example 2 When the produced Oil Red/0 impregnated film is exposed to outdoor light and the relationship between the amount of solar radiation measured by a measuring device and the fading rate is plotted, the relationship is close to a straight line in areas where the fading rate is small, but overall it is There is a logarithmic relationship. In other words, the relationship between the logarithm of the fading rate and the amount of solar radiation is a straight line. This relationship changes depending on the temperature at the time of measurement, and the slope of the fading line becomes steeper as the temperature rises. Therefore, it is necessary to measure the temperature at the time of exposure and use a calibration curve corresponding to that temperature to determine the amount of solar radiation. can. Example 3 As an example of measuring the amount of solar radiation received by the leaves of a tree, we used leaves of the Physcomys cerevisiae. Select a free-standing 4m-tall Physcomitrella branch that faces east, west, north, south, and 3m from the ground, and attach one sheet of PAN dye film to each of the 10 leaves on that branch. The fading rate was measured after exposure for several days. This result shows that branches facing south or east naturally receive more solar radiation, but it turns out that the discoloration rate of IO sheets in the same direction, that is, the variation in H radiation, is greatest in the south.

In this way, with this method, it is possible to easily measure the total amount of solar radiation at multiple points simultaneously. (Table 1) Example 4 To measure the amount of solar radiation on a land sandwiched between building structures, a vacant lot with buildings on three sides (south 6th floor, 100th 4th floor, north 3rd floor) and several trees on one side is 2 m long and wide. The dye film was fixed on rods placed at intervals, and the height from the ground was set to 10 cm. The amount of solar radiation at each location was measured based on the rate of fading after exposure, and a solar radiation map was created.
This method can measure changes in solar radiation due to buildings, and by using a model, it is possible to easily predict in advance the decrease in solar radiation due to a planned building. Example 5 Underwater solar radiation measurement is considered to be an important measurement in relation to water pollution. A dye film was attached to a stage attached to a rod with a floating upper end and a weight at the lower end, and the stage was submerged in water to measure the amount of solar radiation at a constant water depth. The locations were Teganuma, Into-numa, and other lakes. As a result. A contradictory relationship was clearly demonstrated between the degree of water pollution and the cumulative amount of solar radiation underwater. Example 6 When illustrating the relationship between the fading rate for one or several days and the amount of solar radiation measured by a measuring device for Oinore Red/Ofinolem, a line that approximates a logarithmic curve is obtained, and the logarithm of the fading rate and the amount of solar radiation are The relationship is almost linear. Generally, photochemical reactions are temperature dependent, so this film also shows less discoloration in January, February and December when the temperature is low, and more discoloration in July, August and September when the temperature is high. Therefore, to calculate the amount of solar radiation from the fading rate, the temperature at the time of exposure of the measurement plate is measured, and the calculation is done from a pre-made calibration curve at each temperature, or from an equivalent calculation formula. (3) Effects of the present invention As described above, the present invention allows the cumulative total solar radiation to be measured from the fading rate of the pigment measurement plate. This method can be used in many areas, such as measuring the amount of solar radiation received by plants and changing the amount of solar radiation due to artificial structures.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the apparatus for impregnating a film with a dye used in the present invention. Figure 2 is an actual measurement diagram of exposure time and fading rate at a nearly constant temperature. Figure 3 shows the fading regression line for each month. PAN (Exposure period October 8th = January 4th) 1.5m above ground Number of samples Maximum fading value (light intensity) Minimum fading value Standard deviation 3m above ground Maximum fading value Minimum fading value Average fading value East 27.9 5,4 20.6 6.6 South 28.5 15.7 22.0 3.6 West 18.2 5.0 12.6 4.5 3I,2 30,3 25,24,6 1
8,8 16.1 20.2 25 6 22 0 North 18.6 7,6 11.5 2,9 24.4 7,6 16.4 Fig. 1 Sudan 1.5m above ground Sample number fading maximum value (light intensity ) Minimum fading value Average fading value (Exposure period East 4.7 2.7 3.8 October 28-3I) South 4.4 2.4 3.4 West 2.8 1.5 2.1 North 2 .6 0. 9 1.6 Film base dye solution winding motor LoFu

Claims (1)

[Claims] A method in which a measuring plate coated with or impregnated with a pigment that fades or changes color in the range of 5% to 80% due to solar radiation is used for simple integrated solar radiation measurement.