The third paragraph the specific grinding method
That is, the number of fungal colonies in a petri dish is multiplied by the dilution factor of the petri dish inoculum. 2. Sterile water: a 45 mL sterile water triangle bottle with glass beads and a test tube containing 9 mL of sterile water. Equipment Sample: Fresh soil. Experimental steps (1) Experimental procedure 1 Prepare soil dilution solution: 1. A single colony is picked and inoculated on the slant medium.
Step 4: Remove the sample from the Jingxin mill, open the plastic can and pour out the sample. Under normal circumstances, the wooden structure of fir (fir, spruce, cypress) is crunchy. It is easy to grind with steel balls and steel cans. The requirement is to grind the xylem into powder, and then measure the heavy metals and annual rings in the wood by stable isotopes. .
The third paragraph: the specific grinding method of the experimental steps Step 1: the sample and XX ml of ground plastic cans Step 2: put the sample in the XX ml plastic cans, and then put the plastic cans on the Jingxin mill, step 3: Set the parameter grinding frequency XX HZ, and the time can be ground into a powder. It is still the same principle, put the sample and ceramic beads in a plastic jar, put it into the instrument, set the frequency and time, and then grind. (Attach the sample picture)
The second paragraph: Describe the research principle of the sample. The experimental results (comparison of grinding before and after putting), the grinding fineness of the powdered sample can meet the experimental requirements. Note: The samples must be lyophilized for more than XX hours in a lyophilizer. The wooden structure of fir (fir, spruce, cypress) is crisp. To remove the effect of heavy metals on the sample, ceramic Beads and plastic cans were used for experiments. Otherwise, the fibers in the wood are not easy to grind and pulverize, and the oil in the xylem sticks to the wall of the grinding tank and the beads..The first paragraph: Background knowledge. It is easy to grind steel cans by using Shanghai Jingxin multi-sample tissue grinder, but the teacher wants to remove the impact of heavy metals on the sample. Teachers of the School cryotubes of the Environment of Shaanxi Normal University need to do wood experiments
