Particulate Systems NanoPlus, Руководство оператора

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Water NanoPlus Operator’s Manual
B-2 Mar 2014
(1)
Viscosity
Viscosity is a measure of a fluid’s resistance to flow. It describes the internal friction of a moving
fluid. Viscosity is expressed in dyne-seconds per cm
2
or poises (g/cm,s). The common unit for
viscosity in centipoise (cp), which is equal to 0.01 poise. Kinematic viscosity is the ratio of
viscosity to density in stokes (cm
2
/s). The following empirical equations are for the viscosity of
water in centipoises at different temperatures. Equation 2 is for the temperature range from 0 °C to
20 °C, from Hardy, R. C., Cottington, R. L., J. Res. NBS, 1949, 42, 573; and Equation 3 is for the
temperature range from 20 °C to 100 °C, from Swindells, J. F., NBS. This viscosity at 20 °C is
1.002 cp.
(2)
(3)
Dielectric Constant
Dielectric constant is a measure of the amount of electrical charge a given substance can withstand
at a given electric field as compared to air. The following empirical equation is from Maryott and
Smith, NBS Cir. 514, 1951. In the temperature range from 0 °C to 60 °C, the values computed
from the formula are accurate up to four significant figures as compared with the numerical values
in the CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, 1999.
(4)
 
t
  
1.75648 0.013414
 2
–
0.0065438

2
0.11512
2
–
--------------------------------- +
 
 
0.5
0.00204976 – + =
10
3 –
0.124 t 20 –
 
0.1993 t
2
20
2
–
 
0.000005 t
4
20
4
–
 
– +
 
log
10

2
1301
998.333 8.1855 t 20 –
 
0.00585 t 20 –
 
2
+ +
------------------------------------------------------------------------------------------------------------ 1.30233 – =
log
10

t

20
--------
1.3272 20 t –
 
0.001053 t 20 –
 
2
–
t 105 +
------------------------------------------------------------------------------------- 1.30233 – =
D 78.30 1 4.579 10
3 –
t 25 –
 
1.19 10
5 –
t 25 –
  2
2.8 10
8 –
t 25 –
  
–

+

–
 
=