Improved laboratory pretreatment method for silicon implanting body

Abstract

The invention discloses an improved laboratory pretreatment method for a silicon implant, which belongs to the field of extraction treatment in a microbiological laboratory and comprises the following steps: S1, weighing 10g of a dry sample, putting the dry sample into a 500ml glass beaker, and adding deionized water to dissolve the dry sample; s2, after the sample is dissolved, transferring the sample to be subjected to ultrasonic oscillation treatment, and oscillating to decompose a block mass so as to disperse sediment particles; s3, selecting solids with the particle size of 10-200 microns by using a screen analysis method; s4, adding 5ml of diluted hydrochloric acid, fully stirring, and removing iron-calcium carbonate impurities; s5, selecting a main silicic acid solid with the particle size of 10-100 [mu] m; and S6, flaking and observing. Sediment particles are fully dispersed in an ultrasonic oscillation mode by adjusting the experiment sequence, and important prerequisite work is made for silicic acid separation; impurities such as clay and sandy soil are removed in advance through a screening method, the use amount of hydrochloric acid is reduced, and the use cost of the reagent is saved; the flotation extraction step of heavy liquid is omitted, the use cost of reagents is saved, and potential hazards caused by heavy liquid recovery to the environment are also omitted.

Description

Technical Field

[0001] The invention relates to the technical field of microbiological laboratory extraction and processing, and in particular to an improved phytolith laboratory pre-processing method. Background Art

[0002] Plant silicates (phytoliths for short) are amorphous silicon dioxide particles that are precipitated in plants after plants absorb soluble monosilicic acid from the soil through their roots during their growth. They have stable physical and chemical properties, and are corrosion-resistant, high-temperature-resistant, and in-situ deposited. They can be preserved in soil and sediments for a long time after plant tissues die or burn. Since the 1980s, phytoliths have been widely used in paleoenvironmental research, archaeology, Quaternary geology, agronomy, and botany, including research on the classification and naming of phytoliths. In recent years, based on the sensitive response of phytoliths to environmental factors, many scholars have used them as important indicators in paleoenvironmental reconstruction to invert paleovegetation and paleoclimate changes in some regions.

[0003] Phytoliths are distributed in a wide range of plants and are found in different parts of plants (roots, stems, leaves, flowers, fruits, seeds). Once formed in the plant, phytoliths range in size from 5 to 100 μm, sometimes exceeding 1000 μm in diameter.

[0004] Extracting and separating phytoliths by laboratory methods is an important step in conducting relevant research. The present invention mainly discusses general soil and loose sediments (clay, silt, silt, etc.).

[0005] Soil and sediment samples containing phytoliths obtained in the field must first be extracted in the laboratory to remove impurities such as organic matter, clay, quartz sand, etc. in order to obtain high-purity phytoliths with few impurities; therefore, laboratory processing methods to obtain a large number of intact, pure phytoliths are an important step in conducting environmental change research. Summary of the invention

[0006] The above-mentioned existing test methods require the use of chemical reagents such as hydrogen peroxide (H2O2), hydrochloric acid (HCl) and heavy liquid (HI+KOH+Zn solution). These chemical reagents are corrosive and toxic, especially the heavy liquid. Its configuration and recovery are relatively complicated, and the operation steps are relatively cumbersome and unsafe. The present invention provides an improved phytolith laboratory pretreatment method.

[0007] To achieve the above technical solution, the present invention provides an improved phytolith laboratory pretreatment method, comprising the steps of:

[0008] S1: Weigh 10 g of dry sample into a 500 ml glass beaker and add deionized water to dissolve;

[0009] S2: After the sample is fully dissolved, the solution is transferred to ultrasonic vibration treatment to break up the clumps and fully disperse the sediment particles;

[0010] S3: Select solid matter with a particle size of 10 μm-200 μm by sieving;

[0011] S4: Add 5 ml of dilute hydrochloric acid and stir thoroughly to remove a small amount of iron calcium carbonate impurities;

[0012] S5: Selecting the main silicate solids with a particle size of 10 μm-100 μm by sieving analysis;

[0013] S6: Production observation.

[0014] Further, in step S2, ultrasonic treatment is performed at 150 W and 40 kHz for 10 min.

[0015] Furthermore, in step S3, dilute hydrochloric acid with a concentration of 10% is used.

[0016] In summary, the present invention has the following beneficial effects compared with the prior art:

[0017] The present invention adjusts the experimental sequence and fully disperses the sediment particles by ultrasonic vibration, thus completing important prerequisite work for silicate separation; removes impurities such as clay and sand in advance by screening, thereby reducing the amount of hydrochloric acid used and saving the cost of reagents; omits the flotation extraction step of heavy liquid, thus saving the cost of reagents and also eliminating the potential harm to the environment caused by heavy liquid recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 A flowchart of an improved phytolith laboratory pre-treatment method provided by the present invention;

[0020] Figure 2 A microscope picture of a sample in a river delta region obtained by an improved phytolith laboratory pre-treatment method provided by the present invention;

[0021] Figure 3 This is a microscope picture of a river delta sample obtained by an existing method;

[0022] Figure 4 A microscope picture of a deep-sea sediment sample obtained by an improved phytolith laboratory pre-treatment method provided by the present invention;

[0023] Figure 5 This is a microscope image of a deep-sea sediment sample obtained using existing methods. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] See also Figure 1 As shown, the present invention provides an improved phytolith laboratory pre-treatment method, comprising the steps of:

[0026] S1: Weigh 10 g of dry sample into a 500 ml glass beaker and add deionized water to dissolve;

[0027] S2: After the sample is fully dissolved, the solution is transferred to the ultrasonic vibration treatment to break up the clumps and make the sediment

[0028] The particles are fully dispersed;

[0029] S3: Select solid matter with a particle size of 10 μm-200 μm by sieving;

[0030] S4: Add 5 ml of dilute hydrochloric acid and stir thoroughly to remove a small amount of impurities such as iron calcium carbonate;

[0031] S5: Selecting the main silicate solids with a particle size of 10 μm-100 μm by sieving analysis;

[0032] S6: Production observation.

[0033] As a preferred embodiment, in step S2, ultrasonic treatment is performed at 150 W and 40 kHz for 10 min.

[0034] As a preference, in step S3, dilute hydrochloric acid with a concentration of 10% is used.

[0035] The existing phytolith extraction methods generally go through several basic steps: organic matter removal, ultrasonic treatment, iron removal, screening or decantation (removing particles larger than 1000 μm or larger than 200 μm, and using sedimentation to remove particles smaller than 10 μm or smaller than 5 μm), and finally flotation with a heavy liquid with a specific gravity of about 2.30.

[0036] (1) Weigh 10 g of the dry sample into a 500 ml glass beaker and add deionized water to dissolve;

[0037] (2) Add 100 ml of 6% H2O2 and heat on a hot plate to decompose the organic matter. If there is too much organic matter, add 30% H2O2 to continue decomposing.

[0038] (3) The solution after the reaction was transferred to an ultrasonic vibration treatment (150 W, 20 kHz, 10 min) to disperse the clumps and disperse the sediment particles;

[0039] (4) Add dilute hydrochloric acid (10%) and heat (30 min) to remove iron and calcium;

[0040] (5) Selecting solid matter with a particle size of 10-100 μm by sieving and sedimentation;

[0041] (6) flotation with 2.30 gravity liquid;

[0042] (7) Film production observation;

[0043] The important step is to fully disperse the soil clay particles, which determines the quality of silicate separation. The current method requires the use of chemical reagents such as hydrogen peroxide (H2O2), hydrochloric acid (HCl) and heavy liquid, which are corrosive and toxic, especially the heavy liquid, which is more complicated to prepare and recover, and the operation steps are relatively cumbersome.

[0044] In order to verify the superiority of the improved phytolith laboratory pretreatment method provided by the present invention over the above-mentioned existing phytolith extraction method, the present invention conducted the following experiments:

[0045] Note: The methods of the present invention are all carried out at room temperature (23°C-25°C) in a fume hood with good ventilation.

[0046] The experimental measured data are as follows:

[0047] 1. The existing experimental method and the method provided by the present invention were used to separate and extract phytoliths from 10 deep-sea sediment dry samples. The obtained phytolith extracts were identified and counted under a microscope. The results are shown in Table 1:

[0048] Table 1 Number of phytoliths obtained by the existing method and the method provided by the present invention

[0049]

[0050] It can be seen from the random sampling test results that the number of phytoliths obtained by using the improved phytolith laboratory pretreatment method provided by the present invention is significantly increased compared with that obtained by using the existing method. In other words, the improved phytolith laboratory pretreatment method provided by the present invention can obtain more phytoliths in the same sample, thereby greatly improving the experimental efficiency and accuracy of phytoliths.

[0051] 2. Comparison of experimental results of samples collected from different locations

[0052] Samples from different regions have great differences in the types, sizes, shapes, and whether impurities are completely removed from the phytoliths obtained under the microscope. Taking river delta and deep-sea sediment samples as examples, the effects of the two samples after purification are quite different. This is because the samples from the river delta are greatly affected by terrestrial materials and are mainly composed of grass plants. After treatment, there are more impurities such as silt and carbon. Figure 2 The results are obtained by an improved phytolith laboratory pre-treatment method provided by the present invention; Figure 3 By comparing the microscope images of the two, it can be seen that the improved phytolith laboratory pretreatment method provided by the present invention can remove most of the impurities in the sample, making the sample obtained under the microscope clearer.

[0053] Deep sea sediments are less affected by terrestrial materials, with marine plants as the main sediment source. After treatment, there are fewer impurities and the effect is more ideal. Figure 4 The results are obtained by an improved phytolith laboratory pre-treatment method provided by the present invention; Figure 5 The results obtained by the existing treatment. By comparing the microscope images of the two, it can be seen that due to the low impurity components in deep-sea sediments, the proposed effect is more ideal, so the impurity treatment results obtained by the two methods are similar. However, since the number of samples obtained by the method provided by the present invention is greater than the number of samples obtained by the existing method, under the microscope, the results obtained by the method provided by the present invention are clearer than those obtained by the existing method.

[0054] 3. By adjusting the experimental sequence, placing the sample on a mesh sieve for physical filtration, and removing invalid impurities such as carbonates, calcium-containing and iron-containing compounds in advance, the demand for hydrochloric acid in subsequent steps can be reduced (the main function of hydrochloric acid is to remove invalid components such as calcium and iron impurities in the sample).

[0055] That is to say, adopt the original experimental method: because the impurities containing carbonates, calcium and other components are not filtered out, it is necessary to consume 30mL of hydrochloric acid (taking the sample of 130.403194E, 14.278944N of the Philippine Sea sampling point as an example), and the time of the acid reagent chemical reaction is also increased by about 1h. The improved method of the present invention first performs ultrasonic vibration, filters through a mesh screen, and then adds a method of hydrochloric acid, which can filter out the invalid impurities containing carbonates, calcium and other components through a mesh screen in advance, greatly reducing the use of hydrochloric acid to react the invalid impurities, and needs to consume 10ml of hydrochloric acid, and the time of the acid reagent chemical reaction is greatly reduced to 20min.

[0056] 4. No longer using heavy liquid to extract phytoliths can greatly reduce the amount of toxic and harmful chemical reagents used, which is environmentally friendly and reduces the economic expenditure of experimental reagents.

[0057] 5. As shown in Table 2, take 10g of sample and put it into the mesh screen to pass through the oscillator with 20kHz and 40kHz oscillation frequency, and calculate the filtration time. From the data in Table 2, it can be seen that increasing the oscillation frequency of the ultrasonic oscillator from 20kHz to 40kHz can enhance the oscillation efficiency, increase the passing rate of invalid impurities through the mesh screen, and save oscillation filtration time. Taking the samples at the sampling points 130.403194E and 14.278944N in the Philippine Sea as an example, using an oscillator with an oscillation frequency of 20kHz, the mesh filtration time is about 5min; using an oscillator with an oscillation frequency of 40kHz, the mesh filtration time is about 2min.

[0058] Table 2 Comparison of the time of passing through the screen using the existing method and the method provided by the present invention

[0059]

[0060] The present invention improves the existing laboratory pretreatment method of phytolith samples and provides an improved laboratory pretreatment method of phytoliths, which can significantly remove impurities such as iron calcium carbonate, clay, and organic matter, so that a purer pretreatment result can be obtained during the experiment, thereby improving the final expected effect.

[0061] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An improved phytolith laboratory pretreatment method, characterized in that: Includes steps: S1: Weigh 10 g of dry sample into a 500 ml glass beaker and add deionized water to dissolve; S2: After the sample is fully dissolved, the solution is transferred to ultrasonic vibration treatment to break up the clumps and fully disperse the sediment particles; S3: Use sieve analysis to select solid matter with a particle size of 10 μm-200 μm; S4: Add 5 ml of dilute hydrochloric acid and stir thoroughly to remove a small amount of iron calcium carbonate impurities; S5: Selecting main silicate solids with a particle size of 10 μm-100 μm by sieving analysis; S6: Production observation.

2. The improved phytolith laboratory pretreatment method according to claim 1, characterized in that: In step S2, ultrasonic treatment is performed at 150 W and 40 kHz for 10 min.

3. The improved phytolith laboratory pretreatment method according to claim 1, characterized in that: In step S3, dilute hydrochloric acid with a concentration of 10% is used.

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