The relation of phytate concentration to colour produced by standard quantities of thiocyanate and ferric iron in a solution is inverse and almost linear. This is the basis of the method proposed for the determination of phytate phosphorus. It has been applied to the determination of quantities between 75 and 150 ug. in extracts from dried peas with an accuracy of ± 5%. Chloride, sulphate, citrate, tartrate and malate do not interfere in concentrations of the same order as that of the phytate. Interference by o‐I mg. of orthophosphate phosphorus is negligible; 0.4 mg. causes a positive error of less than 5%. It is suggested that there may be less interference in aqueous alcohol.

A pulsed probe has been used to measure certain parameters of a time varying plasma in mercury vapor. Langmuir probe characteristics have been obtained by pulsing the probe voltage to successively higher values for μsec intervals at specific times relative to a repetitive discharge pulse. Curves showing the time dependence of the plasma potential, electron temperature, and electron density relative to this pulse are presented. The probe characteristics do not exhibit a sharp break at the plasma potential. This is related to a disturbance of the plasma by the probe. A novel and precise technique for determining the actual plasma potential is described. This technique depends upon the abrupt appearance of a spike on the leading edge of the probe current pulse.

The absorption coefficient for hydrogen peroxide vapor in the wave-length range 1850–2200A was determined. A careful redetermination of the absorption coefficients for the vapor and for aqueous solutions at 2537A was also made.

nucleus by observing the angular correlation of the emitted particles as a function of time. 2 One would expect a correlation to persist to times of the order of the total spin relaxation time T 2 of the intermediate nuclei j in the sample, perhaps milliseconds or better. 8 We show here how the theoretical delayed coincidence correlation function describing the effect of the magnetic field is to be obtained from the usual correlation function.The equations of the Weisskopf-Wigner treatment of the decay 4 can be made to yield a function W(Qi\ Q 2 ; t-f) which can be interpreted as the rate (steradian -2 sec -1 ) at which particles of the second transition are emitted at time / with direction O2 555 #2, 2+o>oO-WThe delayed coincidence angular correlation pattern is just the instantaneous pattern precessing with the intermediate nucleus around the external field. 8 If the instantaneous correlation is given as a power series in cos0, the corresponding delayed coincidence correlation is obtained as a fourier series in (#4 by transforming the instantaneous correlation to a Legendre series: 9 W(0) = 27JP/(COS0), and then applying the spherical harmonic addition theorem 9 to Pj(o>s0) =Pj(cos0i cos0 2 +sin0i sin0 2 cos(^i-^2)).For example, the instantaneous correlation W(0) = 1+r cos 2 0 = l-f-(r/3)-|-(2f/3)P2(cos0) gives the delayed coincidence correlation (omitting the decay and normalization factors):Wifii, 0 t). (5)In general, the odd harmonics of coo/ drop out if either counter is in the equatorial plane, 0i or 02=90°; and there are no oscillating terms at all if either counter is on the axis, 0i or 02-0° or 180°. The relative amplitudes of the various harmonics are complicated functions ...

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