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A Nd: YAG laser has been operated under strong thermal focusing and birefringent conditions and has yielded both linearly polarized output with negligible power loss and TEM00 output of 50–70% of the multimode power. The laser consisted of two Nd: YAG rods separated by a 90° crystal quartz polarization rotator together with a convex mirror and used no special cooling techniques. The performance of this laser, which agreed with theoretical predictions, indicates that this design approach may be generally applicable to the problem of thermally induced aberrations in such systems.

SUMMARY Reported for the first time are analyses of materials identified with and contributing to the cloud of orange juice. Hexane‐soluble materials provided up to one‐fourth of the cloud‐producing components. In contrast to the composition of structural components of the fruit, cloud components insoluble in alcohol, acetone, and hexane were shown to be rich in nitrogen (ca. 7%), pectins (ca. 80%), and phosphorus (ca. 1.5% as the pentoxide) and to be very low in cellulosic components (ca. 2–5%). This is evidence that cloud originates in the juice cells rather than from mechanical disintegration of structural tissue. No appreciable difference in cloud composition was observed between fruit varieties or between freeze‐damaged and normal fruit.

The electron mobility in Hg1−xCdxTe has been obtained from Hall and resistivity measurements for x as high as 0.6, and in samples with carrier concentrations generally less than 2×1015/cm3. The room-temperature mobility was found to increase uniformly, as x was varied from CdTe, to a maximum value at the semiconductor-semimetal transition. With further reduction in x the mobility drops uniformly again to the HgTe value. Estimates are made of the contributions of various scattering mechanisms to the room-temperature mobility. The effects of optical-mode scattering were calculated for a nondegenerate parabolic band and were the right order of magnitude for compositions as low as x=0.20, but failed to fit the measured results accurately. The ionized impurity scattering mobility was also calculated, and the model of singly ionized donor scattering centers accounts very well for the low-temperature mobility. The results indicate that n-type Hg1−xCdxTe is not compensated to any large extent over a large range in compositions.

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