CN111458362A - Preparation method of polyethylene plastic series standard sample containing 8 heavy metal elements limited in toy field - Google Patents
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Abstract
The invention discloses a preparation method of a polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys, which adopts polyethylene PE as a matrix, and compounds containing lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony, a lubricant and an antioxidant are added, so that the obtained polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys does not change along with the change of time within a certain time, the relative deviation of a detection result is not more than 15%, the standard deviation of the nonuniformity of the sample is far less than the uncertainty of a sample target, the uniformity and the stability of the sample meet the requirements of the standard sample, the blank that no standard sample exists in China at present is filled, the detection level of a participating capacity verification laboratory is improved, and the preparation method can be used for the following aspects: laboratory instrument calibration, method verification and evaluation, quality control, holding capacity verification activities and comparison.
Description
The technical field is as follows:
the invention relates to a preparation method of a polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys.
Background art:
heavy metal elements can enter human bodies through skin, oral cavity and other ways, and cause visceral failure, carcinogenesis and other symptoms, such as blood lead and pain diseases after human bodies are enriched. Because children have weak self-protection consciousness, the children are particularly easy to lick to ingest heavy metal elements in the process of playing the toy. And children have weaker heavy metal discharge capacity at the same time, so that the migratable heavy metals in the toy material can cause higher risk to the health of children. Therefore, the transferable heavy metal elements are harmful chemical substances which are mainly limited in toys and children products, and the toy safety standards of all major toy trade countries in the world almost strictly limit the heavy metal elements, such as the international toy safety standard ISO 8124-3:2018, the Chinese toy safety basic specification GB6675.1-2014, the American consumer goods safety specification ASTM F963-17 and the like. These standards all strictly limit the 8 migratable heavy metal elements of lead, cadmium, mercury, chromium, barium, arsenic, selenium, antimony, and the 17 migratable elements limited by eu toy safety directive 2009/48/EC also include the above 8 elements.
The detection of the migration elements is one of the most classical detection items in the detection field of toys and infant products, but the standard detection method of the migration elements is long in time consumption and low in detection efficiency, in order to rapidly screen the content of specific elements in toy plastics, ASTM F963 firstly proposes that the specific elements in samples can be screened by adopting X-ray fluorescence spectrometry (XRF) when a new edition is released in 2017, but currently, 8-element standard samples for XRF instrument analysis are not available at home and abroad, and instrument curve calibration of related standard samples for XRF screening 8 elements is lacked. Although there are standard samples for XRF analysis of lead, cadmium, mercury and chromium elements in China, the samples do not contain barium, arsenic, selenium and antimony, and 8 elements which are limited by toys are not covered. Due to the blank of this standard sample, the XRF screening 8 element method was not applicable. For huge detection work, the primary screening method for the transferred elements by applying XRF (X-ray fluorescence) quickly and efficiently is very meaningful, the XRF screening method can meet the primary screening requirement of the transferred elements of the toy, the detection efficiency can be greatly improved, and the detection cost can be reduced.
The development of 8-element standard samples in polyethylene plastics for XRF analysis provides standard samples for XRF8 element analysis in laboratories for instrument calibration, quality control in the testing process, comprehensive evaluation on the measuring method and support for examining the laboratory level, and has very important significance for improving the product detection capability and product quality of children in China, ensuring the health of children and maintaining good international reputation of the manufacturing industry in China.
The invention content is as follows:
the invention aims to provide a preparation method of a polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys.
The invention is realized by the following technical scheme:
a preparation method of a polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys is disclosed, wherein the 8 heavy metal elements are lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony, the standard sample adopts polyethylene PE as a matrix, and compounds containing lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony, a lubricant and an antioxidant are added, and the concentration ranges of lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony in the sample are 4 levels according to the mass percentage of a final product: concentration level 1: 7-60 mg/kg; concentration level 2: 30-240 mg/kg; concentration level 3: 75-600 mg/kg; concentration level 4: 150-1200 mg/kg; the method comprises the following steps:
1) determining the weight of a series of standard samples of polyethylene plastics containing 8 heavy metal elements limited in the field of toys to be prepared, and simultaneously considering the loss in the preparation process to be 20-30 wt% of the raw materials;
2) premixing: adding a compound containing 8 heavy metal elements and a lubricant which are ground and pass through a 200-mesh stainless steel sieve according to the content of the required target element, and fully mixing until the surface color of the sample is uniform; simultaneously adding an antioxidant into the polyethylene granules to enable the surface of the PE granules to be fully distributed with the antioxidant, and then fully mixing the antioxidant and the PE granules in a high-speed mixer until the surface color of a sample is uniform to obtain a premix; the grinding, wherein the crystalline compound is ground by a ball mill and the other compounds are ground manually;
3) blending and extruding: placing the premix obtained in the step 2) into a double-screw extruder for blending and extruding, controlling the rotating speed at 350 r/min and the temperature at 100-;
4) uniformly mixing the master batch and the blank sample according to the preset concentration, continuously extruding through a single screw twice, granulating, and tabletting into plastic wafers with the diameter of 39-41mm and the thickness of 3.8-4.2 mm;
5) the prepared samples were stored with ambient temperature maintained between 10-30 ℃ and humidity maintained between 30-85%.
In particular, the compounds containing lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony are respectively selected from Pb3O4、CdS、HgO、K2Cr2O7、BaBO4、As2O3、Na2SeO3、Sb2O3。
The sample adopts the Polyethylene (PE) commonly used in toy materials as a matrix, so that the matrix of the sample is close to the actual sample, and a certain amount of antioxidant is added into the matrix, so that the surface of PE particles is fully covered with the antioxidant, and the problem that the PE material is easy to oxidize in the processing process is solved.
The key technical points of the invention are as follows:
1. the selection of the formula, the selected base material and the selected auxiliary materials can ensure that the 8 elements of the added target substances of lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony can be fused with the base material, and the target elements cannot be volatilized and lost.
2. In the process technology, some target raw materials are in a crystal state and are difficult to be uniformly mixed in the plastic, and other raw materials containing target elements are difficult to be uniformly dispersed in the plastic. Therefore, the raw materials are ground and sieved before being mixed with the matrix material, and then the number of revolutions and time for mixing, the viscosity of the plastic, and the blending temperature and time need to be considered.
3. The stability of the sample, the storage condition of the prepared sample and the control of the temperature and the humidity are considered and strictly controlled, and the content of each element in the sample is ensured not to change along with the change of time in a certain time period.
4. The standard value of the standard sample is one of the most important parameters of the standard sample, but the XRF analysis method has large fluctuation and is difficult to accurately determine the value of the sample.
The invention has the following beneficial effects:
1) according to the invention, before the raw materials are added, the raw materials are ground and pretreated, so that the problem of poor uniformity of the target object in the plastic sample is solved. And then fully mixing the raw materials and the PE material particles in a high-speed mixer until the surface color of the sample is uniform, and continuously extruding and granulating the mixture twice through a screw to prepare master batches. And granulating twice to fully and uniformly mix the sample.
2) The method comprises the steps of firstly preparing master batches, then uniformly mixing the master batches and blank samples according to the preset concentration, continuously extruding the mixture twice through a single screw, and pelletizing. Then tabletting into plastic wafers. The invention firstly prepares the master batch, and then gradually dilutes the master batch, so as to better control the concentration of the target object and ensure that the target object is distributed in a gradient way.
3) After the sample is prepared, ICP-OES is adopted to measure the total content of lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony elements in the sample, and uniformity inspection, stability inspection and customization are carried out on the sample, and uncertainty evaluation is carried out at the same time. The relative deviation of the detection results of the prepared standard samples of lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony is not more than 15%.
In a word, the polyethylene plastic series standard sample containing 8 heavy metal elements limited in the toy field does not change along with the change of time within a certain time, the relative deviation of the detection result is not more than 15%, the standard deviation of the nonuniformity of the sample is far less than the target uncertainty of the sample, the uniformity and the stability of the sample meet the requirements of the standard sample, the blank that no standard sample of the type exists in China at present is filled, the polyethylene plastic series standard sample can be applied to 8 transferable elements limited in the XRF screening toy field, the preliminary screening requirement of the toy transfer elements can be met, the detection efficiency can be greatly improved, the detection cost can be reduced, the detection level of a laboratory is improved, and the polyethylene plastic series standard sample containing 8 heavy metal elements limited in the toy field can be: laboratory instrument calibration, method verification and evaluation, quality control, holding capacity verification activities and comparison.
Description of the drawings:
FIG. 1 is a schematic diagram of a series of standard samples (concentration level 4: 150-1200 mgkg) of polyethylene plastics containing 8 heavy metal elements limited in toy field for XRF analysis;
FIG. 2 is a schematic diagram of a series of standard samples (concentration level 3: 75-600 mgkg) of polyethylene plastics containing 8 heavy metal elements limited in toy field for XRF analysis;
FIG. 3 is a schematic diagram of a series of standard samples (concentration level 2: 30-240 mgkg) of polyethylene plastics containing 8 heavy metal elements restricted by toy field for XRF analysis;
FIG. 4 is a schematic diagram of a series of standard samples (concentration level 1: 7-60 mgkg) of polyethylene plastics containing 8 heavy metal elements limited in toy field for XRF analysis.
Detailed Description
The following is a further description of the invention and is not intended to be limiting.
Example 1:
first, preparation of sample
1. When 4 series concentrations of 50 sets of polyethylene plastics are required to be prepared, about 8kg of master batch samples are firstly required to be prepared, and then the master batch samples are gradually diluted to the series concentrations. The master batch and the contents of each concentration level are shown in table 1.
TABLE 1
2. Calculating the weight of the raw material compound to be added
The addition amount of the raw material is the content x of each element, the final weight of the master batch/the content of the target element in the raw material.
The weight of starting compound required to be added was calculated according to the above data and the formula provided, and the results are shown in table 2:
TABLE 2
| Name of raw material | Purity of raw material | Raw material weight (g) |
| BaBO4 | Analytical purity | 129.84 |
| K2Cr2O7 | Analytical purity | 67.92 |
| Pb3O4 | Analytical purity | 26.47 |
| HgO | Analytical purity | 25.92 |
| CdS | Analytical purity | 30.84 |
| Sb2O3 | Analytical purity | 28.73 |
| Na2SeO3 | Analytical purity | 140.16 |
| As2O3 | Analytical purity | 10.72 |
3. The ball mill converts the crystal K2Cr2O7Grinding, sieving with 200 mesh stainless steel sieve, and manually grinding other target additives, and sieving with 200 mesh stainless steel sieve.
4. Premixing: taking the ground raw material mixture, adding a certain lubricant to fully mix the target additive until the color of the surface of the sample is uniform; adding a certain amount of antioxidant into Polyethylene (PE) granules to enable the surfaces of the PE granules to be fully distributed with the antioxidant, so as to prevent the PE from being oxidized in the processing process; and then fully mixing the raw materials and the PE granules in a high-speed mixer until the color of the surface of the sample is uniform.
5. Blending and extruding: and (3) placing the uniformly mixed premix into a double-screw extruder, controlling the general rotating speed at 350 r/min and the temperature at about 100 ℃ and 130 ℃, blending and extruding, and continuously extruding and pelletizing through the screw twice to prepare the master batch.
6. And (3) uniformly mixing the master batch and the blank sample according to the preset concentration, continuously extruding by a single screw twice, and granulating. Then tabletting into plastic round pieces with the diameter of about 39-41mm and the thickness of 3.8-4.2 mm.
7. And (4) the prepared sample is delivered to a sample manager for storage, and the stored sample cabinet is provided with a special lock person for taking charge. The temperature of the environment for storing the sample is kept between 10 and 30 ℃, and the humidity is kept between 30 and 85 percent.
Second, uniformity detection
According to GB/T15000.3-2008 "general principles and statistical methods for standard sample valuing", the standard sample development adopts a single-factor analysis of variance method and a comparison method of uniformity uncertainty to evaluate the uniformity of a sample. Referring to ISO GUIDE35-2017, when the number of samples is less than 100, 10% of samples or 3 samples are taken for uniformity test of the samples, and the two samples are taken as big as 50 sets of samples, so 5 samples are taken for uniformity test. All samples were numbered, 5 samples were randomly drawn from the population (randomly generated using the function rand of excel, the rand function was inserted in the cell of the excel table and multiplied by the total number of samples to give 5 random numbers, corresponding to the sample number being the random number), each sample was tested 4 times under repetitive conditions, the samples were processed according to the method of standard ISO 8124-5:2015, each sample had a mass of about 0.1 g. And (3) making a standard curve on an ICP-OES instrument by using a standard solution prepared by a national standard sample, measuring the contents of 8 elements in the filtrate by using the ICP-OES according to a random sequence, and finally evaluating the uniformity of the standard sample by using a single-factor variance analysis and uniformity uncertainty comparison method. The results of the uniformity tests are shown in tables 3-6.
TABLE 3 results of homogeneity test on the standard samples (concentration level 1: 7 ~ 60mg/kg)
| Sample numbering | As | Ba | Cd | Cr | Hg | Pb | Sb | Se |
| MSWorkshop | 0.4 | 1.21 | 0.1 | 1.95 | 0.37 | 0.28 | 0.61 | 17.62 |
| MSInner part | 0.6 | 1.08 | 0.18 | 1.42 | 0.83 | 0.25 | 0.24 | 17.46 |
| Between df | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| df inner (VMS inner) | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 |
| sbb | 0 | 0.18 | 0 | 0.36 | 0 | 0.08 | 0.30 | 0.2 |
| ubb* | 0.24 | 0.31 | 0.13 | 0.36 | 0.28 | 0.15 | 0.15 | 1.26 |
| ubb | 0.24 | 0.31 | 0.13 | 0.36 | 0.28 | 0.15 | 0.30 | 1.26 |
| F(statistics) | 0.59 | 1.12 | 0.57 | 1.37 | 0.44 | 1.1 | 2.53 | 1.01 |
| F(critical) | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 |
| 0.3utrg | 0.12 | 0.89 | 0.28 | 0.36 | 0.32 | 0.31 | 0.31 | 0.8 |
| 0.7utrg | 0.28 | 2.07 | 0.65 | 0.84 | 0.75 | 0.73 | 0.72 | 1.87 |
TABLE 4 results of uniformity test for the Standard samples (concentration level 2: 30 to 240mg/kg)
TABLE 5 results of homogeneity test on the samples (concentration level 3: 75-600 mg/kg)
| Sample numbering | As | Ba | Cd | Cr | Hg | Pb | Sb | Se |
| Between MS | 2.5 | 74.89 | 5.96 | 26.93 | 14.83 | 2.08 | 3.82 | 439.74 |
| In MS | 1.3 | 57.66 | 4.36 | 23.08 | 9.93 | 4.79 | 4.83 | 194.44 |
| Between df | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| df inner (VMS inner) | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 |
| sbb | 0.56 | 2.08 | 0.63 | 0.98 | 1.11 | 0.00 | 0.00 | 7.83 |
| ubb* | 0.34 | 2.29 | 0.63 | 1.45 | 0.95 | 0.66 | 0.66 | 4.21 |
| ubb | 0.56 | 2.29 | 0.63 | 1.45 | 1.11 | 0.66 | 0.66 | 7.83 |
| F (statistics) | 1.99 | 1.30 | 1.37 | 1.17 | 1.49 | 0.43 | 0.79 | 2.26 |
| F (Critical) | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 | 3.06 |
| 0.3utrg | 1.05 | 8.21 | 2.69 | 3.15 | 3.19 | 3.00 | 2.88 | 7.68 |
| 0.7utrg | 2.44 | 19.17 | 6.27 | 7.34 | 7.44 | 7.00 | 6.72 | 17.93 |
TABLE 6 results of uniformity test on the standard samples (concentration level 4: 1500. about.1200 mg/kg)
The results in tables 3-6 show that each element F was present in 4 samples of different concentrations(statistics)Are all less than F(critical value)No significant difference between samples was shown at 3.06. To further verify the homogeneity of the samples, the homogeneity of the samples was checked using a comparative method of uncertainty. As can be seen from the results of tables 1 to 4, the concentration levels of As and Se elements at 1, the concentration levels of Cr element at H1714, and the concentration levels of u element at Se element at 3 are shownbb>0.3utrgBut less than 0.7utrgAnd u of the several elementsCRM≤utrgU of elements of other samplesbbAre all less than 0.3utrgThe standard sample is proved to have good uniformity and meet the expected application. U of all elements in order to avoid underestimation of uncertaintybbWill be included in the total uncertainty synthesis of the standard samples.
Thirdly, testing the stability of the sample
1. Long term stability test
To control the reproducibility of the stability verification test, the stability verification was performed by the same experimenter for all tests. Storing the sample at room temperature, and inspecting the stability of the standard sample at a certain time interval by adopting an ISO8124-5 test method according to the stability inspection requirement of GB/T15000.3 and the principle of density before density and density after density. The interval time of stability test is 0 month, 0.5 month, 1.5 month, 3.5 month, 5.5 month, 7.5 month, 9.5 month, 12 month, 14 month, 17 month, 19 month, 21 month respectively. The samples were tested for 6 replicates at each time point. And taking the average value of the test results as the data of the current stability test. Statistical tests were performed according to the standard sample stability method recommended by GB/T15000.3, and a straight line was used as an empirical model since there was no physical/chemical model that could truly describe the degradation mechanism of the candidate standard sample. The results of the stability tests are shown in tables 7-10.
TABLE 7 stability test results for the Standard samples (concentration level 1: 7 ~ 60mg/kg)
TABLE 8 stability test results for the Standard samples (concentration level 2: 30 to 240mg/kg)
TABLE 9 stability test results for the Standard samples (concentration level 3: 75-600 mg/kg)
TABLE 10 stability test results for the Standard samples (concentration level 4: 150-1200 mg/kg)
From tables 5 to 8, it can be seen that | b of each element1All are less than s(b1)*t(0.95，10). It is shown that the standard sample does not undergo significant trend changes in magnitude during the stability testing period, i.e., the stability of the sample is good.
2. Short term stability test
Considering that the short-term stability of the standard sample is mainly the influence of short-term transportation under temperature change conditions on the characteristic quantity, the experiment allows the sample to be stored for a short term under the conditions of temperature (50 ℃) and temperature (-20 ℃) to examine the short-term stability. The method adopts ISO8124-5 test method, simulates transportation conditions at different temperatures, and monitors the short-term instability of the standard sample in different time intervals. According to GB/T15000.3, samples were tested 6 times at-20 ℃ at 50 ℃ under repeated conditions at each time point. The time for sample transport will generally not exceed two weeks, as per the actual transport situation, so the simulated transport conditions were investigated for stability of the samples over a two week period. The test results are shown in Table 11.
Table 11 short term stability test data units: mg/kg
The average consistency test method is adopted for testing and evaluating the short-term stability. The results of the short term stability analysis are shown in Table 12.
TABLE 12 short term stability statistics
As can be seen from Table 12, the statistical value t of each element after transportation(experiment)Are all less than the critical value t(0.95,10)2.228, which shows that the characteristic value of the standard sample does not change significantly under the transportation conditions of-20 ℃ and 50 ℃ within 2 weeks, and the short-term stability of the sample is good.
Fourth, sample constant value
And (4) according to the requirements of GB/T15000.3, the candidate is subjected to valuing by adopting a plurality of laboratory cooperation valuing methods. The fixed value is participated in 9 laboratories at this time, and the fixed value is approved by CNAS and has higher level in the detection field. The 9 laboratories come from third-party detection laboratories, government detection units and are distributed in different regions and fields.
In the setting process, 9 samples of each concentration sample are randomly drawn out and distributed to 9 laboratories for measurement, and each sample is repeatedly measured for 6 times. All laboratories of this time carry out the test according to the ISO8124-5 standard method.
The results of the evaluation value test in the 9 laboratories are shown in tables 13-16.
TABLE 13 (concentration level 4: 150-1200 mg/kg) quantitative results are in Table units: mg/kg
TABLE 14 (concentration level 3: 75-600 mg/kg) quantitative results Table Unit: mg/kg
TABLE 15 (concentration level 2: 30-240 mg/kg) quantitative results are in TABLE units: mg/kg
TABLE 16 (concentration level 1: 7-60 mg/kg) quantitative results Table Unit: mg/kg
Fifth, uncertainty assessment
Gauge for uncertainty evaluation according to GB 15000.3The contribution of the standard sample definite value, uniformity and stability to the total uncertainty of the measured value needs to be considered. Using the standard uncertainty (u) due to the measurementchar) Standard uncertainty due to inhomogeneity (u)hom) Standard uncertainty due to long term instability (u)lts) As a component of each uncertainty, an uncertainty (u) is synthesizedCRM). The component calculation of each uncertainty is performed according to the relevant terms and formulas of GB 15000.3. The result of the expansion uncertainty for each element is shown at 17.
TABLE 18 standard sample extension uncertainty for each element
Claims (2)
1. The preparation method of the polyethylene plastic series standard sample containing 8 heavy metal elements limited in the field of toys is characterized in that the 8 heavy metal elements are lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony, the standard sample adopts polyethylene PE as a matrix, and compounds containing lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony, a lubricant and an antioxidant are added, and the concentration ranges of the lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony in the sample are 4 levels according to the mass percentage of a final product: concentration level 1: 7-60 mg/kg; concentration level 2: 30-240 mg/kg; concentration level 3: 75-600 mg/kg; concentration level 4: 150-1200 mg/kg; the method comprises the following steps:
1) determining the weight of a series of standard samples of polyethylene plastics containing 8 heavy metal elements limited in the field of toys to be prepared, and simultaneously considering the loss in the preparation process to be 20-30 wt% of the raw materials;
2) premixing: adding a compound containing 8 heavy metal elements and a lubricant which are ground and pass through a 200-mesh stainless steel sieve according to the content of the required target element, and fully mixing until the surface color of the sample is uniform; simultaneously adding an antioxidant into the polyethylene granules to enable the surface of the PE granules to be fully distributed with the antioxidant, and then fully mixing the antioxidant and the PE granules in a high-speed mixer until the surface color of a sample is uniform to obtain a premix; the grinding, wherein the crystalline compound is ground by a ball mill and the other compounds are ground manually;
3) blending and extruding: placing the premix obtained in the step 2) into a double-screw extruder for blending and extruding, controlling the rotating speed at 350 r/min and the temperature at 100-;
4) uniformly mixing the master batch and the blank sample according to the preset concentration, continuously extruding through a single screw twice, granulating, and tabletting into plastic wafers with the diameter of 39-41mm and the thickness of 3.8-4.2 mm;
5) the prepared samples were stored with ambient temperature maintained between 10-30 ℃ and humidity maintained between 30-85%.
2. The method for preparing a polyethylene plastic series standard sample containing 8 heavy metal elements restricted in toy field according to claim 1, wherein the compounds containing lead, cadmium, mercury, chromium, barium, arsenic, selenium and antimony are selected from Pb, Cd, Hg, Cr, Ba, As, Se and Sb respectively3O4、CdS、HgO、K2Cr2O7、BaBO4、As2O3、Na2SeO3、Sb2O3。
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080233652A1 (en) * | 2005-11-15 | 2008-09-25 | Martin Kreyenschmidt | Set of Calibration Standards |
| CN103245538A (en) * | 2013-04-17 | 2013-08-14 | 广州赛宝计量检测中心服务有限公司 | Preparation method of standard sample for X spectrofluorimetry |
| CN103275412A (en) * | 2013-04-20 | 2013-09-04 | 东莞龙昌智能技术研究院 | Preparation method for standard substance for plasticizer added in ABS-modified polyvinyl chloride |
| WO2016003347A1 (en) * | 2014-07-01 | 2016-01-07 | Eklund Britta | Set of calibration standards and their use in a method of quantifying biocides in anti-fouling paints with a portable xrf instrument |
| CN106633505A (en) * | 2016-11-26 | 2017-05-10 | 金发科技股份有限公司 | Preparation method of standard sample composed of more than ten elements (As, Se, P and the like) and multiple phthalates in polyvinyl chloride (PVC) |
-
2020
- 2020-03-18 CN CN202010191325.8A patent/CN111458362B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080233652A1 (en) * | 2005-11-15 | 2008-09-25 | Martin Kreyenschmidt | Set of Calibration Standards |
| CN103245538A (en) * | 2013-04-17 | 2013-08-14 | 广州赛宝计量检测中心服务有限公司 | Preparation method of standard sample for X spectrofluorimetry |
| CN103275412A (en) * | 2013-04-20 | 2013-09-04 | 东莞龙昌智能技术研究院 | Preparation method for standard substance for plasticizer added in ABS-modified polyvinyl chloride |
| WO2016003347A1 (en) * | 2014-07-01 | 2016-01-07 | Eklund Britta | Set of calibration standards and their use in a method of quantifying biocides in anti-fouling paints with a portable xrf instrument |
| CN106633505A (en) * | 2016-11-26 | 2017-05-10 | 金发科技股份有限公司 | Preparation method of standard sample composed of more than ten elements (As, Se, P and the like) and multiple phthalates in polyvinyl chloride (PVC) |
Non-Patent Citations (1)
| Title |
|---|
| 王斌 等: "用于X射线荧光光谱法测定聚丙烯材料中有害元素的标准样品的制备", 《理化检验-化学分册》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114295663A (en) * | 2021-12-28 | 2022-04-08 | 自然资源部第二海洋研究所 | Magnesium-based electron probe microbeam component analysis standard sample and preparation method thereof |
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