| 摘要 |
<p>Appts. for accurately diluting liquid solns. has a series of double ended pistons sliding in opposed pairs of cylinders. The pistons have collars on their central portions which can be engaged by a claw to move the piston either up or down. The space under each piston communicates via a fine hole with a slotted valve shaft. As this turns the space is sealed, placed in communication with a drain, or with the space over the top of the cylinder. Programmed movements of the pistons in conjunction with turning of the valve shaft can pass the soln. along from one piston cylinder assembly to the next, so that at each assembly the soln. is diluted to 1/2 strength.</p> |
