English literature about denitrification is too difficult for me.

2 days ago, I was doing experiment from morning to 18 o'clock.
yesterday, I was made to read unknown English literature for 2 hours.
my brain got tired.

after that, I washed experiment instruments.

wash by tap water 3 times
↓
put them in sound wave washing machine for 10 minutes
↓
wash by tap water 5 times
↓
wash by distillated water 3times
↓
put them into heater or drying machine


I was made to do them again just touch directly inside instruments by hand.ww

too morbid love of cleanliness!!