References

References
Physical constants - Electricity - Microscopy and Optics - Unit Conversion - US Drill Size -
Resistor Codes - Capacitor Codes- 2008 Calendar

Useful pH ranges of selected buffers at 25 ^oC
5.5-7.9

Buffer	MES	BIS-TRIS	ADA	ACES	PIPES	MOPSO	BIS-TRIS PROPANE	BES	MOPS
pKa	6.1	6.5	6.6	6.8	6.8	6.9	6.8; 9.0	7.1	7.2
pH Range	5.5-6.7	5.8-7.2	6.0-7.2	6.1-7.5	6.1-7.5	6.2-7.6	6.3-9.5	6.4-7.8	6.5-7.9

6.8-8.7

Buffer	TES	HEPES	DIPSO	TAPSO	TRIZMA	HEPPSO	POPSO	TEA	EPPS
pKa	7.4	7.5	7.6	7.6	8.1	7.8	7.8	7.8	8.0
pH Range	6.8-8.2	6.8-8.2	7.0-8.2	7.0-8.2	7.0-9.0	7.1-8.5	7.2-8.5	??	7.3-8.7

7.4-11.1

Buffer	TRICINE	GLYCYL -GLYCINE	BICINE	TAPS	AMPSO	CHES	CAPSO	AMP	CAPS
pKa	8.1	8.2	8.3	8.4	9.0	9.3	9.6	9.7	10.4
pH Range	7.4-8.8	7.5-8.9	7.6-9.0	7.7-9.1	8.3-9.7	8.6-10.0	8.9-9.3	??	9.7-11.1

For more detailed information please refer to Sigma Aldrich Corp.

Major physical constants k=1.38 x10-23joule/grad; R= 8.31 joule/mol*grad; F=96,487 coulomb/g-mol;
c = 2.997925 x 10E8 m/s; h=6.63 x 10E-34 joule*s; N_A=6.023*10E23 mol-1;
g = 9.8 m/s² ; ¶ = 3.141;

Kjuri? = 3.7*10E10 s-1.
Electron Charge =1.6*10E-19 coulomb.
Electron Mass =9.11*10E-28 g.
Proton Mass = 1.67*E-24 g.

Speed of sound in air = 332 m/s; Speed of light = 2997925*10E8 m/s.

Electricity R[Ohm]=U[volt]/I[amper]. G[Siemens]=1/R. P[watt]=UxI=I²R=U²R. C[farad]=Q[coulomb]/U[volt].

Resistivity of selected materials - þ - [Ohm*m*10E-8]: Silver - 1.64; Copper - 1.72; Aluminum - 2.83; Nichrom - 100.
Resistance of a conductor with length L and crossection S:
R = þ*L[m]/S[m2]

GHK equation:

E₀ = (RT/F)*ln[(P_K*K_out + P_A*A_in)/(P_K*K_in + P_A*A_out)]

were: P_x - permeability, X_out, X_in concentrations inside & outside of ion selective membrane

Microscopy and Optics

Photometric units: 1 candle = 1 lumen/steradian; 1 lux = meter candle = lumen/m2

E = h v = h c/Wavelength;

Refractive Index: n = sinß¹/sinß²
Were ß is an angle between normal to surface and light beam
ⁿ_air^{= n}_vac.^{= 1; n}_water^{= 1.33; n}_oil^{= 1.52}

Numerical Aperture: NA = n · sinß
Were ß is an angle between objective axis and line connecting focal point to the edge of first lens.

Resolution: d[µm] = Wavelength [µm]/(NA_obj+NA_cond.)

Useful Magnification: MU =500-1000 · NA_obj

Depth of Focus:
{(1000 · Mobj.) / (7 · NAobj. · MU)} + {(Wavelength[µm] · MObj²) / (2 · NAObj.²⁾}

Unit Conversion Length
1nm =10Å; 1"=25.4 mm; 1' = 30.5 cm;
1 km = 0.62 mile (0.64 sea mile) 1 mile =1.61 km
1yard=91.4 cm
Angle 1 Radian = 180^o/¶ = 57.3^o

Area 1 acre = 4840 sq. yard = 43560 sq. feet = 4047 sq. meter = 0.405 gectare

Volume
1 liter = 61.02 cubic inch = 0.03531 ft³= 0.264 gallon = 1.06 quart = 33.81fluid ounce; 1 quart = 0.946 liter.

Mass
1 kg = 1000g = 2.2 lb;
454 gramm (g) = 1 pound (lb) = 16 ounces; 1ounce (oz) = 28g

Temperature/Energy:
^oC = (^oF - 32)/1.8 = ^oK-273.
1cal=4.18joule = 0.003968 BTU = 3.968e-8 term
1 Joule = 10E7 erg.

Pressure
1 atmosphere (techn.) = 0.968 atm (phys.) = 1 kg/sm2 = 0.9807 bar = 98070 pascal = 14.22 psi = 735.6 cm of Hg

1 Tesla = 10000 Gauss = 7.96x 10e5 A/m

Technical US Drill Size number/Diameter in mm.
97 92 83 78 73 67 60 53 47 39 31 21 9
0.15 0.2 0.3 0.4 0.6 0.8 1.0 1.5 2.0 2.5 3.0 4.0 5.0

B J O T X
6.0 7.0 8.0 9.1 10.1

Resistor Color Codes

COLOR	Black	Brown	Red	Orange	Yellow	Green	Blue	Violet	Gray	White
DIGIT	0	1	2	3	4	5	6	7	8	9
Multiplier	x1	x10	x100	x1K	x10K	x100K	x1M	--	--	--

Divider: Silver =x 0.01; Gold = x0.1
Tolerance: None = 20%; Silver=10%; Gold =5%.
More info.

Small Capacitor Codes
First two digits – Value in pico-Farads (1 pF=10e-12 F)
Third digit – multiplier [1=10; 2=100; 3=1000; 4=10000; 5=100000]
Letter – tolerance [D=+/- 0.5%; F=1%; G=2%; H=3%; K=10%; M=20%; P=+100%,-0% ; Z=+80%, -20%]
Examples: 47= 47pF; 683=68000pF; 102K=1000pF +/- 10%.
More info.

Eastern Scientific LLC - 13114 Midway Ave., Rockville, MD 20851 USA
www.eastsci.com, e-mail. sales@eastsci.com Fax. 240-399-4486

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Date of latest modification: 3-2-2018