| 摘要 |
655,310. Caps for discharge tubes. PHILIPS ELECTRICAL, Ltd. Dec. 9, 1947, No. 32422. Convention date, Oct. 5, 1946. [Class 38 (i)] [Also in Group II] To prevent corrosion of the ferro-chromium wire contacts 3 of a valve 1, they are chemically polished by being dipped in cleansing fluid, preferably containing perchloric acid and acetic acid anhydride. |
