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I K Ludlow

Publications and source records attributed to I K Ludlow.

3 recordsLinked to original sources

Inverse Mie problem.

We apply functional analysis to the scattered electromagnetic field of a particle with spherical symmetry to obtain a pair of integral transforms for converting the Mie-scattering amplitudes S perpendicular (theta) and S parallel (theta) into the Mie coefficients an and bn. In the case of a homogeneous sphere, a simple mathematical construction is derived that uniquely inverts the Mie coefficients to find the refractive index and the radius of the particle. A more general method for construction of the refractive-index profile of an arbitrary sphere is discussed that follows from the treatment of Newton and Sabatier.

Journal Article↗

The application of laser diffractometry to study the water content of spores of Bacillus sphaericus with different heat resistances.

The distribution of water in the protoplast and integument of three populations of Bacillus sphaericus spores was determined by laser diffractometry together with the sizes of their integuments and protoplasts. The spores were produced at 15, 20 and 30 degrees C. Spores grown at 15 degrees C had protoplast and integument water contents similar to those produced at 20 degrees C, while those grown at 30 degrees C had significantly lower water contents than the other two populations. The inner (or protoplast) radii of the spores produced at 15, 20 and 30 degrees C were 0.41 +/- 0.02 microns, 0.42 +/- 0.01 microns and 0.38 +/- 0.02 microns whilst the outer (or whole spore) radii were 0.56 +/- 0.01 microns, 0.58 +/- 0.01 microns and 0.52 +/- 0.02 microns respectively. The ratios of integument to protoplast radius were 0.40 +/- 0.02, 0.43 +/- 0.07 and 0.41 +/- 0.03 respectively.

Bacillus↗