Some standard content:
Ministry of Electronics Industry of the People's Republic of China Technical Document General Rules for the Use of Spectral Sensitive Plates
SJ/Z 8206.4—89
This standard specifies the performance, selection, use rules and preparation of emulsion characteristic curves for photographic spectrochemical analysis.
The definitions of terms used in this standard can be found in GB9259-88 (Terms of Emission Spectral Analysis). 1
Natural Performance of Photosensitive Plates
The technical indicators for evaluating the performance of spectral sensitive plates include: color range, sensitivity, resolution, contrast and fog. The sensitivity, contrast and fog can be reflected by the emulsion characteristic curve. Emulsions can be divided into: unsensitized, orthochromatic, isochromatic, isochromatic, panchromatic and isochromatic according to their color range. 1.1 Emulsion characteristic curve
The emulsion characteristic curve shows the relationship between the blackness of the spectrum line on the sensitive plate and the logarithm of the light quantity. See the figure. S
OlegHib
Figure emulsion characteristic curve
Figure, AB—underexposed part
BC—normal exposure part
CD—overexposed part
So—fog blackness
In the normal exposure part (BC), S=Y (logH-logHi) In the formula, S blackness
Approved by the Ministry of Electronics Industry of the People's Republic of China on February 10, 1989 (1)
Implemented on March 1, 1989
—contrast,
H—light intensitybzxZ.net
Hi—extreme contrast.
SJ/Z 3206.4--89
The shape of the emulsion characteristic curve is related to the emulsion properties and the spectral wavelength. However, in the range of 200-330nm, the contrast does not change much.
1.2 Preparation of emulsion characteristic curve
The emulsion characteristic curve is prepared based on the relationship between blackness S and the logarithm of noise light quantity logH. Because the exposure H is determined by two factors, light intensity and light time, when preparing the emulsion characteristic curve, the light intensity can be changed by fixing the exposure time or the exposure time can be changed by fixing the light intensity. The methods for preparing the emulsion characteristic curve include the spectral line group method, the step dimmer method, the step fan plate method and the two-line method. This standard only introduces two methods. 1.2.1 Spectral line group method
In the spectrum of a certain element, select several spectral lines to form a spectral line group as the intensity scale, and draw a graph with the logarithm of the relative intensity I of these spectral lines as the horizontal axis and the blackness S as the vertical axis. The spectral line group used to prepare the emulsion characteristic curve should meet the following conditions: a. All spectral lines must belong to the same element (here limited to iron element), and the wavelengths of the spectral lines are as close as possible. In this spectral region, the emulsion contrast does not change significantly. b. The relative intensity of all spectral lines must be known, and the intensity range is relatively wide. c. The spectral lines should have similar excitation characteristics and self-absorption properties. When the working conditions of the light source fluctuate, the intensity ratio of the spectral lines does not change.
The following table lists three groups of iron spectral lines. The first two are suitable for DC arcs, and the latter is suitable for AC arcs and high-voltage sparks. Table 1.2.2 Step dimmer method
Step dimmers usually have three steps, six steps, and nine steps. For making emulsion characteristic curves, a nine-step 2
SJ/Z3206.4—89
dimmer is usually used. Seven steps of the dimmer are sprayed with platinum layers of different densities, and the other two steps are used to check the uniformity of the dimmer illumination. The dimmer should be free of dust, fingerprints and scratches, with uniform coating and clear boundaries between the steps. When making emulsion characteristic curves, the step dimmer is usually placed in front of the spectrograph slit and as close to the slit as possible. Each time the noise light is taken, nine steps of each spectral line can be photographed at the same time. In a certain band, select a spectral line and measure the black value of each step. With the logarithm of the transmittance of these steps (i.e. the logarithm of the relative intensity of light logR) as the horizontal coordinate and the corresponding blackness S as the vertical coordinate, the emulsion characteristic curve can be drawn. 1.3 Spectral conditions for emulsion correction
1.3.1 The center of all lenses must be on the optical axis of the spectrometer. The optical axis of the cylindrical lens must be correctly oriented, the guide rail must be parallel to the optical axis of the spectrometer, and when the lens is moved away from the slit, the center of the lens must remain on the optical axis.
1.3.2 Before placing the step dimmer, the intensity of each spectral line in the spectrum must be uniform over the entire height used.
1.3.3 Use inter-imaging. Minimize the continuous spectral background emitted by hot solids, such as electrode heads, and do not allow it to be projected onto the optical elements inside the spectrograph. Light inside the spectrograph should fall only on optical elements (e.g., lenses, reflectors, mirrors, gratings) and not on their supports or other locations inside the spectrograph.
1.3.4 For spectrographs where the wavelength range of the captured image can be changed, the emulsion should be calibrated at exactly the same wavelength position as the analytical exposure.
1.3.5 The light source used for emulsion calibration should emit sufficient spectral lines in all relevant wavelength ranges and be operated in the same manner and for approximately the same time period as the specimen exposure. 1.4 Spectral sensitivity The sensitivity of the photographic plate to monochromatic radiation of different wavelengths can be expressed in the following ways: a. Expressed as the reciprocal of the sensitivity to each wavelength. b. Expressed as the reciprocal of the exposure (Hso+1.0) of the wavelength required on the photosensitive surface to produce a blackness exceeding 1.0, that is,
Sx\Hso+1.0
Where: S is the reciprocal of the exposure,
Hso is the exposure.
1.5 Domestic spectral sensitive plates
For the models and performance of spectral sensitive plates produced by Tianjin Photographic Film Factory, see Appendix A. 2 Selection of sensitive plates
(2)
2.1 Spectral sensitive plates and films used for spectral analysis are required to have uniform texture, small characteristic differences caused by different wavelengths, good reciprocity, long straight line portions of the emulsion characteristic curve, and appropriate contrast. 2.2 Select sensitive plates according to the wavelength range of the analysis line. For sensitive wavelengths between 210 and 500 nm, use orthochromatic plates, and for 680 nm, use panchromatic plates. When analyzing in a special wavelength range, use infrared or far ultraviolet sensitive plates. 2,3 Because the contrast of the photosensitive plate changes with the nature of incident light, storage status and development operating conditions, the emulsion characteristic curve should be drawn according to the specified development conditions when necessary to determine the change in contrast. When it is necessary to expand the linear range of the working curve, it is more appropriate to use a photosensitive plate with a smaller contrast. 2.4 In order to take a spectrum with good resolution, it is desirable to use an emulsion with fine silver grains. When doing microanalysis, an emulsion with a higher sensitivity is used.
3 Storage and use of spectral photosensitive plates
3.1 The number of purchased photosensitive plates is only for use in the next few months. Confirm that the photosensitive plates are within the validity period and are used up within the specified period of use.
3.2 Pressuring the emulsion surface of the photosensitive material will cause it to produce gray fog. Therefore, photosensitive plates should not be piled up and pressed, but should be stored vertically.
3,3 Because the characteristics of the photosensitive plate are prone to change in hot and humid places, it is also easy to produce gray fog. The sealed packaging box of the photosensitive plate, especially the highly sensitive photosensitive plate or the photosensitive plate for use in the visible or infrared region, should be stored at a temperature of about 8.
3.4 To avoid condensation of water vapor on the cold surface, the photosensitive plate should be placed for at least 4 hours before being taken out of the cold storage and unsealed, and the temperature of the sealed box should return to room temperature. Do not refreeze after unsealing. If it is stored in the refrigerator without sealing, a desiccant should be used.
3.5 Turpentine vapor, coal gas, hydrogen sulfide, formaldehyde, and industrial waste gas can cause the photosensitive plate to scorch, so care should be taken to prevent contact.
3.6 Photosensitive materials should be protected from radiation from X-rays and radiation. In places with radioactive materials, the photosensitive plate should be stored in a lead-wrapped container.
3.7 The photosensitive plate must be opened under the safety light specified in the instructions, and the safety light used must be tested to see if it is reliable. The working wavelength of the photosensitive plate used for general spectral analysis is below 500nm, and the red light is used as a safety light. 3.8 When cutting the photosensitive plate, place it with the emulsion side facing down on a cutting board rack covered with clean and smooth paper or flannel to prevent scratching the emulsion surface. Use a glass cutter to cut the glass surface once, break the glass along the cut and then break the emulsion in the opposite direction.
3.9 When taking the photosensitive plate, do not touch the emulsion surface with your fingers, otherwise it will leave marks on the emulsion surface. The remaining photosensitive plates should be packed according to the original packaging method and put into the box to prevent light leakage. 4
Ultraviolet type I
Ultraviolet type II
Ultraviolet type III
Blue fast type
Blue hard type
Blue extra hard type
Blue super hard type
Yellow fast type
Yellow extra hard type
Red fast type
Red extra hard type
Additional instructions:
SJ/Z3206.4-89
Attachment A
Models and performance tables of light-sensitive plates produced by Tianjin Photosensitive Film Factory (reference)
Sensitivity
40±15
45±15
50±20
Contrast
This standard was proposed by the Electronic Standardization Institute of the Ministry of Machinery and Electronics Industry. Gray
This standard was drafted by the 772 Factory and the Electronic Standardization Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Fang Zhixian, Zhao Changchun and Huang Wenyu. Color sensitive range nm
250~500
250~500
250400
250~500
250~500
250~500
250~500
300~600
300~600
300~700
300~700
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.