Protective fluid for alumina, protection method, and production method for semiconductor substrate having alumina layer using same
US-12338381-B2 · Jun 24, 2025 · US
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Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
Nitrogen oxides; Oxyacids of nitrogen; Salts thereof · Cooperative Patent Classification (CPC)
Chemical and metallurgical processes, compounds, and materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | C01B21/20 |
| Official title | Nitrogen oxides; Oxyacids of nitrogen; Salts thereof |
| Display label | Nitrogen oxides; Oxyacids of nitrogen; Salts thereof |
| Total patents | 20 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is rapidly declining.
| Year | Patents |
|---|---|
| 2015 | 1 |
| 2016 | 1 |
| 2017 | 2 |
| 2018 | 3 |
| 2019 | 3 |
| 2020 | 3 |
| 2021 | 2 |
| 2022 | 1 |
| 2024 | 3 |
| 2025 | 1 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
A solid-gas reaction to generate nitroxyl (hno) in the gas phase
US-2024269164-A1 · Aug 15, 2024 · US
Ammonia generator using plasma
US-2024254635-A1 · Aug 1, 2024 · US
Methods for Oxidizing a Nitrogen Oxide to Nitrate
US-2024190706-A1 · Jun 13, 2024 · US
Catalyst support systems for ammonia oxidation burners
US-11485639-B2 · Nov 1, 2022 · US
NOx adsorber catalyst
US-11117097-B2 · Sep 14, 2021 · US
Protective fluid for alumina, protection method, and production method for semiconductor substrate having alumina layer using same
US-2021002551-A1 · Jan 7, 2021 · US
Catalyst support systems for ammonia oxidation burners
US-2020338518-A1 · Oct 29, 2020 · US
Gas sensor and method of manufacturing the same
US-10598628-B2 · Mar 24, 2020 · US
Single step solution combustion synthesis of crystalline transuranic-doped rare earth zirconate pyrochlores
US-10590005-B2 · Mar 17, 2020 · US
Single step solution combustion synthesis of crystalline transuranic-doped rare earth zirconate pyrochlores
US-2019300384-A1 · Oct 3, 2019 · US
Selective catalytic reduction steady state ammonia slip detection with positive perturbation
US-10344654-B2 · Jul 9, 2019 · US
Selective catalytic reduction steady state ammonia slip detection with positive perturbation
US-2019078480-A1 · Mar 14, 2019 · US
NOx ADSROBER CATALYST
US-2018094559-A1 · Apr 5, 2018 · US
Electrode comprising a transition metal oxidenitride or a nitrogen-doped transition metal oxide as electronically active material
US-9929405-B2 · Mar 27, 2018 · US
Gas sensor and method of manufacturing the same
US-2018003669-A1 · Jan 4, 2018 · US
Basket-like device having wall insulation
US-9725320-B2 · Aug 8, 2017 · US
Vapour deposition process for the preparation of a phosphate compound
US-9533886-B2 · Jan 3, 2017 · US
Basket-like device having wall insulation
US-2016200575-A1 · Jul 14, 2016 · US
Adsorbent
US-9192913-B2 · Nov 24, 2015 · US