CN111678879A - Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI - Google Patents
Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI Download PDFInfo
- Publication number
- CN111678879A CN111678879A CN202010007813.9A CN202010007813A CN111678879A CN 111678879 A CN111678879 A CN 111678879A CN 202010007813 A CN202010007813 A CN 202010007813A CN 111678879 A CN111678879 A CN 111678879A
- Authority
- CN
- China
- Prior art keywords
- water sample
- peroxyformic acid
- hydrogen peroxide
- concentration
- determining
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 title claims abstract description 54
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 44
- SCKXCAADGDQQCS-UHFFFAOYSA-N Performic acid Chemical compound OOC=O SCKXCAADGDQQCS-UHFFFAOYSA-N 0.000 title claims abstract description 39
- 238000000034 method Methods 0.000 title claims abstract description 22
- 150000002978 peroxides Chemical class 0.000 claims abstract description 10
- 238000002835 absorbance Methods 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 9
- 239000008363 phosphate buffer Substances 0.000 claims description 4
- 239000000243 solution Substances 0.000 abstract description 4
- 229910019142 PO4 Inorganic materials 0.000 abstract 1
- 239000008366 buffered solution Substances 0.000 abstract 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 abstract 1
- 239000010452 phosphate Substances 0.000 abstract 1
- 239000002953 phosphate buffered saline Substances 0.000 description 8
- KFSLWBXXFJQRDL-UHFFFAOYSA-N Peracetic acid Chemical compound CC(=O)OO KFSLWBXXFJQRDL-UHFFFAOYSA-N 0.000 description 4
- 239000003054 catalyst Substances 0.000 description 4
- -1 cerium titration Chemical compound 0.000 description 4
- LOKCTEFSRHRXRJ-UHFFFAOYSA-I dipotassium trisodium dihydrogen phosphate hydrogen phosphate dichloride Chemical compound P(=O)(O)(O)[O-].[K+].P(=O)(O)([O-])[O-].[Na+].[Na+].[Cl-].[K+].[Cl-].[Na+] LOKCTEFSRHRXRJ-UHFFFAOYSA-I 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 238000002798 spectrophotometry method Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000007865 diluting Methods 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 150000007524 organic acids Chemical class 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000004448 titration Methods 0.000 description 2
- ZTOJFFHGPLIVKC-YAFCTCPESA-N (2e)-3-ethyl-2-[(z)-(3-ethyl-6-sulfo-1,3-benzothiazol-2-ylidene)hydrazinylidene]-1,3-benzothiazole-6-sulfonic acid Chemical compound S\1C2=CC(S(O)(=O)=O)=CC=C2N(CC)C/1=N/N=C1/SC2=CC(S(O)(=O)=O)=CC=C2N1CC ZTOJFFHGPLIVKC-YAFCTCPESA-N 0.000 description 1
- IIQFOVQMXGABDP-UHFFFAOYSA-N 3-ethyl-2-[(3-ethyl-6-sulfo-2h-1,3-benzothiazol-2-yl)diazenyl]-2h-1,3-benzothiazole-6-sulfonic acid Chemical compound S1C2=CC(S(O)(=O)=O)=CC=C2N(CC)C1N=NC1N(CC)C2=CC=C(S(O)(=O)=O)C=C2S1 IIQFOVQMXGABDP-UHFFFAOYSA-N 0.000 description 1
- HQFLTUZKIRYQSP-UHFFFAOYSA-N 3-ethyl-2h-1,3-benzothiazole-6-sulfonic acid Chemical compound OS(=O)(=O)C1=CC=C2N(CC)CSC2=C1 HQFLTUZKIRYQSP-UHFFFAOYSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 229910052684 Cerium Inorganic materials 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000002479 acid--base titration Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 238000000967 suction filtration Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/33—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using ultraviolet light
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention relates to a method for determining peroxyformic acid and coexisting hydrogen peroxide in water by utilizing KI, which mainly comprises the steps of adding PBS (phosphate buffered solution), KI, Mo (VI) and a water sample to be treated, mixing the solutions, determining absorbance by an ultraviolet spectrophotometer and calculating according to a formula, and effectively and accurately determining the concentration of the peroxyformic acid and the coexisting hydrogen peroxide in the water by calculating the total peroxide concentration and the peroxyformic acid concentration, wherein the difference value of the total peroxide concentration and the peroxyformic acid concentration is the concentration of the coexisting hydrogen peroxide.
Description
Technical Field
The invention belongs to the field of water quality monitoring in the environment, and particularly relates to a method for determining peroxyformic acid and coexisting hydrogen peroxide in a water sample by using KI.
Background
Peroxyformic acid has a strong oxidizing property and is generally used as an oxidizing agent in water treatment. The acid, which is present as a mixture of peroxyformic acid, hydrogen peroxide, formic acid and water, is extremely unstable in nature and starts to decompose after 120 minutes after the preparation is complete.
The preparation process of the peroxyformic acid is extremely simple, the reaction process does not need to add any organic or inorganic catalyst, the concentration of the prepared peroxyformic acid can reach 3M at most when the reaction condition is appropriate, and in addition, the peroxyformic acid can also replace chlorine and peroxyacetic acid and be used for the water disinfection process. Therefore, there is a need to develop a reliable, accurate, inexpensive, and rapid method for quantitatively determining the concentration of PFA in a water sample.
Titration is the most commonly used method for detecting the content of peroxyformic acid, including cerium titration, acid-base titration, etc., however, these methods are labor intensive, time consuming, and difficult to accurately determine the concentration in micromolar order; in addition, there are also some methods for measuring the concentration of the peroxyformic acid by a spectrophotometric method, for example, N-diethyl-p-phenylenediamine (DPD) is used as an indicator, and 2,2' -azobis (3-ethylbenzothiazoline-6-sulfonate) is oxidized by using 3-ethylbenzothiazoline-6-sulfonate (ABTS) as a catalyst, respectively, to measure and calculate the concentration of the peroxyformic acid. Although the spectrophotometric method is more accurate in measuring the organic acid with low concentration, the measurement cost is higher and the time consumption is longer. In summary, there are many general methods available for determining the concentration of peroxyacetic acid, but methods specifically designed for determining the concentration of peroxyformic acid in water samples are relatively lacking.
Disclosure of Invention
The invention aims to overcome the defects of the conventional method for measuring peroxyformic acid and hydrogen peroxide in water, and provides a method for measuring peroxyformic acid and coexisting hydrogen peroxide in water by utilizing KI.
The invention aims to solve the technical problems in the background art, adopts the technical scheme that the method for determining peroxyformic acid and coexisting hydrogen peroxide in a water sample by utilizing KI comprises the following steps:
1) 1.4mL of PBS (phosphate buffer, 0.5M, pH4.5) was added to the beaker;
2) slowly add 0.1mL of KI (1.2M) into the beaker;
3) adding 1mL of water sample to be measured into the beaker, and uniformly mixing;
4) after the solution had reacted for 30 seconds, its absorbance at 350nM wavelength was measured by an ultraviolet spectrophotometer and found to be A1(350nm)；
5) Another 1 beaker was added with 1.4mL of PBS (phosphate buffered saline, 0.5M, pH4.5);
6) 0.1mL of KI (1.2M) and 0.05mL of Mo (VI) were then added;
7) finally, adding 1mL of water sample to be measured, mixing uniformly, measuring the absorbance of the water sample at the wavelength of 350nm, and recording as A2(350nm)；
A obtained in the step 4)1(350nm) and calculating the concentration of the peroxyformic acid in the water sample by the formula (1).
A obtained in the step 7)2(350nm) and calculating the concentration of the total peroxide in the water sample by the formula (2).
The difference between the total peroxide concentration and the peroxyformic acid concentration is the concentration of the coexisting hydrogen peroxide.
K in the above formula (1)PFAIs 4.1 × 103M-1。
K in the above formula (2)[H2O2+PFA]Is 1.11 × 104M-1。
Spectrophotometric determination of peroxyformic acid using KI as an indicator is a rapid and inexpensive method for determining peroxide and organic acid concentrations by oxidizing excess KI with peroxyformic acid and hydrogen peroxide to form iodate ions. Because mo (vi) is a catalyst, hydrogen peroxide reacts faster with iodide ions in its presence and competes with hydrogen peroxide because it is a catalyst. Thus, the formation of yellow is detected using an ultraviolet spectrophotometer with a wavelength of 350 nm. By the method, the concentrations of the hydrogen peroxide and the peroxyformic acid in the water sample can be effectively determined, and the method is short in time consumption, low in cost and beneficial to popularization.
Advantageous effects
Oxidizing excess KI with peroxyformic acid and hydrogen peroxide in the presence of Mo (VI) to form iodate ions, and detecting the formation of yellow color using an ultraviolet spectrophotometer having a wavelength of 350 nm;
2. the method determines the concentration of the peroxyformic acid and the total peroxide, and then calculates the concentration of the hydrogen peroxide according to the difference of the two;
3. high sensitivity and high measuring speed.
Detailed Description
The present invention will be further described with reference to the following examples.
Example 1
For water samples containing impurities, the specific implementation mode is as follows:
1) a water sample needs to be pretreated firstly, and is filtered by using a suction filtration device, wherein a filter membrane is a 0.22um filter membrane;
2) diluting a water sample by 10 times, 50 times and 100 times;
3) 1.4mL of PBS (phosphate buffer, 0.5M, pH4.5) was added to a 100mL beaker;
2) slowly adding 0.1mL of KI (1.2M) into a 100mL beaker;
3) adding 1mL of the water sample to be measured diluted in the step 2) into the beaker, and uniformly mixing;
4) after the solution had reacted for 30 seconds, its absorbance at 350nM wavelength was measured by an ultraviolet spectrophotometer and found to be A1(350nm)；
5) Another 1 beaker was added with 1.4mL of PBS (phosphate buffered saline, 0.5M, pH4.5);
6) 0.1mL of KI (1.2M) and 0.05mL of Mo (VI) were then added;
7) finally, adding 1mL of water sample to be measured, mixing uniformly, measuring the absorbance of the water sample at the wavelength of 350nm, and recording as A2(350nm)；
And (3) calculating according to a formula 1 and a formula 2 to obtain the concentrations of the peroxyformic acid and the total peroxide, wherein the difference value of the two is the concentration of the hydrogen peroxide.
Example 2
For water samples with higher pH, the specific implementation mode is as follows:
1) the pH value of a water sample is close to 7 by dripping dilute hydrochloric acid;
2) diluting a water sample by 10 times, 50 times and 100 times;
2) slowly adding 0.1mL of KI (1.2M) into a 100mL beaker;
3) adding 1mL of the water sample to be measured diluted in the step 2) into the beaker, and uniformly mixing;
4) after the solution had reacted for 30 seconds, its absorbance at 350nM wavelength was measured by an ultraviolet spectrophotometer and found to be A1(350nm)；
5) Another 1 beaker was added with 1.4mL of PBS (phosphate buffered saline, 0.5M, pH4.5);
6) 0.1mL of KI (1.2M) and 0.05mL of Mo (VI) were then added;
7) finally, adding 1mL of water sample to be measured, mixing uniformly, measuring the absorbance of the water sample at the wavelength of 350nm, and recording as A2(350nm)；
And (3) calculating according to a formula 1 and a formula 2 to obtain the concentrations of the peroxyformic acid and the total peroxide, wherein the difference value of the two is the concentration of the hydrogen peroxide.
Claims (6)
1. A method for determining peroxyformic acid and coexisting hydrogen peroxide in a water sample by utilizing KI is characterized by comprising the following steps of:
1) 1.4mL of PBS (phosphate buffer, 0.5M, pH4.5) was added to the beaker;
2) slowly add 0.1mL of KI (1.2M) into the beaker;
3) adding 1mL of water sample to be measured into the beaker, and uniformly mixing;
4) after the solution had reacted for 30 seconds,the absorbance at 350nM wavelength was measured by UV spectrophotometer and found to be A1(350nm)；
5) Another beaker was added with 1.4mL of PBS (phosphate buffer, 0.5M, pH4.5);
6) 0.1mL of KI (1.2M) and 0.05mL of Mo (VI) were then added;
7) finally, adding 1mL of water sample to be measured, mixing uniformly, measuring the absorbance of the water sample at the wavelength of 350nm, and recording as A2(350nm)；
2. The method for determining the peroxyformic acid and the co-existing hydrogen peroxide in the water sample by the KI according to claim 1, wherein the A obtained in the step 4) is1(350nm) and calculating the concentration of the peroxyformic acid in the water sample by the formula (1).
3. The method for determining the peroxyformic acid and the co-existing hydrogen peroxide in the water sample by the KI according to claim 1, wherein the A obtained in the step 7) is2(350nm) and calculating the concentration of the total peroxide in the water sample by the formula (2).
4. The method for determining the peroxyformic acid and the co-existing hydrogen peroxide in the water sample by the KI according to claim 1, wherein the difference between the total concentration of the peroxide and the concentration of the peroxyformic acid is the concentration of the co-existing hydrogen peroxide.
5. The method for determining the peroxyformic acid and the co-existing hydrogen peroxide in the water sample by the KI according to claim 1, wherein k in the formula (1) isPFAIs 4.1 × 103M-1。
6. The method for determining the peroxyformic acid and the co-existing hydrogen peroxide in the water sample by the KI according to claim 1, wherein k in the formula (2)[H2O2+PFA]Is 1.11 × 104M-1。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010007813.9A CN111678879A (en) | 2020-01-05 | 2020-01-05 | Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010007813.9A CN111678879A (en) | 2020-01-05 | 2020-01-05 | Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111678879A true CN111678879A (en) | 2020-09-18 |
Family
ID=72433206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010007813.9A Pending CN111678879A (en) | 2020-01-05 | 2020-01-05 | Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111678879A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090150086A1 (en) * | 2007-06-05 | 2009-06-11 | Ecolab Inc. | Wide range kinetic determination of peracid and/or peroxide concentrations |
| WO2015196272A1 (en) * | 2014-06-24 | 2015-12-30 | Klox Technologies Inc. | Biophotonic compositions comprising halogen and uses thereof |
| CN107449745A (en) * | 2017-07-17 | 2017-12-08 | 华侨大学 | The visible spectrophotometric assay method of concentration of hydrogen peroxide in a kind of water |
| US20180172651A1 (en) * | 2016-12-15 | 2018-06-21 | Ecolab Usa Inc. | Colorimetric detection and quantitative estimation of peracids using a redox sensitive leuco dye |
| CN109187399A (en) * | 2018-07-23 | 2019-01-11 | 华侨大学 | A kind of method of Peracetic acid and content of hydrogen peroxide in quick measurement solution |
| US20190302071A1 (en) * | 2016-07-21 | 2019-10-03 | Lonza Inc. | Method and Kit for Determining Peracetic Acid Concentration in Disinfectant Solutions |
-
2020
- 2020-01-05 CN CN202010007813.9A patent/CN111678879A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090150086A1 (en) * | 2007-06-05 | 2009-06-11 | Ecolab Inc. | Wide range kinetic determination of peracid and/or peroxide concentrations |
| WO2015196272A1 (en) * | 2014-06-24 | 2015-12-30 | Klox Technologies Inc. | Biophotonic compositions comprising halogen and uses thereof |
| US20190302071A1 (en) * | 2016-07-21 | 2019-10-03 | Lonza Inc. | Method and Kit for Determining Peracetic Acid Concentration in Disinfectant Solutions |
| US20180172651A1 (en) * | 2016-12-15 | 2018-06-21 | Ecolab Usa Inc. | Colorimetric detection and quantitative estimation of peracids using a redox sensitive leuco dye |
| CN107449745A (en) * | 2017-07-17 | 2017-12-08 | 华侨大学 | The visible spectrophotometric assay method of concentration of hydrogen peroxide in a kind of water |
| CN109187399A (en) * | 2018-07-23 | 2019-01-11 | 华侨大学 | A kind of method of Peracetic acid and content of hydrogen peroxide in quick measurement solution |
Non-Patent Citations (1)
| Title |
|---|
| 董娜等: "二苯胺磺酸钠催化动力光度法测定过氧化氢酶活性" * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109612951A (en) | For detecting chlorine residue in water/total chlorine detection agent and preparation method thereof and detection method | |
| CN111474168A (en) | Residual chlorine analysis method | |
| Choi et al. | Development of sulphide-selective optode membranes based on fluorescence quenching | |
| CN116256355A (en) | On-line measurement, calibration and quality control method for total chlorine of residual chlorine | |
| Hollowell et al. | Selective determination of chlorine dioxide using gas diffusion flow injection analysis | |
| Scheurer et al. | Colorimetric submicromethod for determination of ammonia | |
| Saad et al. | Development of flow injection spectrophotometric methods for the determination of free available chlorine and total available chlorine: comparative study | |
| Karlberg et al. | The determination of penicillins by titrations with mercury (II) solution | |
| Kinani et al. | A Critical Review on Chemical Speciation of Chlorine-Produced Oxidants (CPOs) in Seawater. Part 2: Sampling, Sample Preparation and Non-Chromatographic and Mass Spectrometric-Based Methods | |
| CN111678879A (en) | Method for determining peroxyformic acid and coexisting hydrogen peroxide in water sample by utilizing KI | |
| Safavi et al. | A PVC-membrane bulk optode for gallium (III) ion determination | |
| CN107449744B (en) | Analysis method for detecting catalase activity in textile printing and dyeing industry | |
| Saad et al. | Sequential flow injection determination of chlorine species using a triiodide-selective electrode detector | |
| Utley | Simultaneous determination of hydroxylamine and cyanide in formulations containing pralidoxime salts by flow injection | |
| CN111504926A (en) | Method for measuring peroxyacetic acid content | |
| CN111537503A (en) | Sulfide analysis method and automatic analyzer | |
| Brunner et al. | Analysis of developers and bleach for Ansco Color Film | |
| RU2105296C1 (en) | Method of determining nitrite ion in solution | |
| Chamjangali et al. | Development of a Simple and Inexpensive Optical Absorption One‐Shot Sensor Membrane for Detection and Determination of Cyanide Ions in Water Samples | |
| CN117607082B (en) | Method for measuring concentration of each oxidant in mixed solution of peroxymonosulfate and free chlorine based on iodometry and application of method | |
| CN110501330B (en) | Method for rapidly detecting content of hydrogen peroxide | |
| Smart | Measurement of chlorine dioxide with a membrane chemiluminescence cell | |
| Brown et al. | Determination of chlorine in concentrated sulfuric acid solution with a residual chlorine electrode | |
| CN114739988B (en) | Method for detecting volatile phenol in wastewater | |
| RU2495404C1 (en) | Method for spectrophotometric determination of concentration of chlorine dioxide and chlorite ions in drinking water |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20200918 |