662 



SUBJECT INDEX 



Microscopy (continued) : 



opaque specimens, 354-8 



phase, 366-8 



ultra, 360 



ultraviolet, 352-4 

 Microspectroscopes, 375 

 Millicurie, 605 



Milliroentgen, 639. See also Roentgen. 

 Mixtures, method of (calorimetry). 



176-9 

 Mobility, measurements, 284-6 



particles, 274-7 

 Molecular extinction coefficient, 424 

 Molecular fragments (mass spectrom- 

 etry), 570-1, 579 

 Molecular weight, determination from 



osmotic pressure, 42-45 

 Monitoring ionizing radiation, 638-43 

 Monochromators, 433-4 

 Mutations, bacterial, 480-2 



Drosophila, 476-9 



ionizing radiations, 468 ff., 498-500 



Neurospora, 469, 499 



N 



Neher-Harper circuit, 617-8 



Nernst equation, 239-41 



Neurospora, as irradiation material, 



469, 499 

 Neutrons, 491 ff. See also Ionizing 

 radiations. 

 collimation, 531 

 dose rates, 530-2 

 energy absorbed, 552-3 

 fast, measurement, 546-53 



sources, 528-32 

 ion density, 502-4 

 relative dose in various materials, 



552 

 slow, measurement, 553-5 



sources, 532-5 

 thermal, biological effects, 533-5 



sources, 532-5 

 tissue dose, 553 

 yield, 528-30 

 Nier mass spectrometer, 574-6 

 Nitrogen, disintegration, 533-4 



Nitrogen (continued): 



iso topic analysis, 579-81, 584-6 



metabolism, 568, 595 

 Numerical aperture, 345-7, 410 



O 



Oblique illumination, 359 



Oculars, compensating, 374-5 

 special, 374-5 



Ohm's law, 237, 262-4 



Optical path differences, phase micros- 

 copy, 368 



Optical sectioning, 347 



Optical staining, 360-1 



Oscillators (ultrasonics), 314-26 



Oscillographs, 259 



Oseen's law, 113 



Osmometers, 61-64 



dynamic equilibrium type, 63, 65 

 static elevation type, 62, 65 



Osmotic pressure, definition, 39 

 origin 40 



Osmotic pressure measurements, 39-66 

 accuracy, 44, 56-59 

 direct osmometer method, 61-64 

 freezing point method, 56-58 

 importance in biophysics, 42-45 

 plasmolysis method, 59-61 

 usefulness, 42-45 

 vapor pressure method, 58, 59, 65 

 theoretical considerations, 45-55 

 thermodynamic considerations, 46- 

 52 



Paramecia, viscosity studies, 120, 126 

 Permeability, membranes, 42-45, 268 

 Phase microscopy, 366-8 

 Phosphorescent specimens, 363-5 

 Photobiological processes, 417-9 

 Photocells, 427 



Photochemical reactions, 417-9, 435-8 

 PhotodjTiamic action, 419 

 Photoelectric photometry, 427 

 Photographic methods, 27 

 Photographic recording of radioac- 

 tivity. See Rndioautographs. 



