Ob-point calibration ntawm pH testers
Rau precision pH meters, ntxiv rau qhov chaw thiab qhov kub thiab txias kev hloov kho, kuj tseem muaj kev hloov kho electrode, yog li ob lub buffers yuav tsum tau siv rau calibration. Feem ntau, pib qhov chaw (calibration) nrog pH6.86 lossis pH7. 0.0l (alkaline) tsis raws li pH ntawm cov tshuaj ntsuam xyuas.
Qhov thib ob, cov kauj ruam ua haujlwm tiag tiag yog raws li hauv qab no:
(1) Ntxuav thiab qhuav cov electrode, tsau rau hauv cov tshuaj siv pH 6. Tom qab tus nqi qhia tau ruaj khov, kho qhov chaw qhov rooj kom qhov ntsuas qhov ntsuas yog pHs tus nqi ntawm cov kev qhia tshwj xeeb.
(2) Tshem tawm cov electrode, ntxuav nws, tig qhuav, thiab tsau rau hauv cov tshuaj ntawm qhov kev qhia thib ob. Tom qab tus nqi qhia tau ruaj khov, kho txoj kab nqes pob qhov rooj ntawm qhov ntsuas kom tus nqi qhia ntawm qhov ntsuas yog pHs tus nqi ntawm cov txheej txheem thib ob.
(3) Tshem tawm cov electrode, ntxuav nws, tig nws kom qhuav, thiab tom qab ntawd tsau rau hauv cov tshuaj tsis haum pH 6.86 lossis pH 7.00. Yog tias qhov ua yuam kev dhau 0.02 pH, rov ua cov kauj ruam (1) thiab (2) kom txog thaum nws tuaj yeem hloov kho yam tsis hloov lub pob qhov rooj. Cov pH raug raug qhia hauv ob qho kev daws teeb meem.
(4) Tshem tawm cov electrode thiab tig nws qhuav, kho pH kub them pob qhov rooj rau qhov ntsuas kub ntawm cov qauv tshuaj, tsau cov electrode hauv cov qauv tshuaj, viav vias nws, thiab tom qab ntawd cia nws sawv ntsug kom txog thaum kev nyeem ntawv ruaj khov.
