Orion star a111 ph meter

The possible variation of pH upon addition of increasing amounts of glycerol to different buffers was monitored at room temperature (27 °C ± 0.5) with a Crison GLP 21 pH-meter. The initial pH was measured in 47.5 mL of each buffer at a concentration of 0.1 M. Aliquots of glycerol and fresh buffer were properly added to the initial volume to obtain 5, 10, 15, 20, and 30% (v/v) glycerol/buffer solutions. For each concentration point, the solution was stirred with magnetic agitation for 5 min to avoid inhomogeneities in liquid density before measuring the pH. The pH stability of the buffers was also tested with a Thermo Scientific Orion Star A111 pH-meter at room temperature (23 °C ± 0.5) in the presence of 20% (v/v) of ethylene glycol, 0.36 M of sucrose or 0.36 M of trehalose.

Soil salinity and pH were calculated in the field (Table S1). Five '5 cm diameter' cores of soil were collected adjacent to sampled plants, with the exception of the seagrass samples. Cores were taken to 10 cm depth and thoroughly mixed. A sample of 20 g of soil was placed in a vessel and 100 mL of distilled water was added. The mixture was shaken periodically over one hour, then allowed to stand for 30 min before measuring the salinity (calculated from electrical conductivity) and pH using an EC8500 portable pH and conductivity meter (Apera Instruments, Ohio) according to the manufacturer's instructions. A temperature compensation coefficient of 2%/ o C was used for calculating salinity. pH measurements were later confirmed in the laboratory using an Orion Star A111 pH meter (Thermo Fisher Scientific, Massachusetts).