The reflection factor of neutrons by phantoms was determined experimentally. Two kinds of phantom were used in the experiments, resulting in well coinciding data. This phenomenon indicates that the reflection factor is determined by the surface tissue lying within several centimeters of the skin surface, and is independent of the size and shape of the phantoms. The reflection factor was found to fall only very slowly with energy, providing that a thermal neutron detector on the surface of the human body may be used to measure the dose-equivalent of neutrons of incident energies up to 10 keV.

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Two positive delivery pipetters (1 ml and 5ml in capacity) have been devised for pipetting aliquots of highly radioactive liquid samples intended, various analytical deteminations in the reprocessing analytical facility at the Japan Atomic Energy Research Institute.
The pipetter assembly consists of pipet, electrical elevator, control unit, three valves and trap, as well as nitrogen gas and vacuum lines.
The structural material of the parts of the pipet in contact with the sample are either stainless steel or teflon.
A precision of 0.2% standard deviation of successive 100μl deliveries of distilled water and concentrated nitric acid was obtained on the 1 ml pipetter.
Design criteria for the pipetter, its principle of operation and method of decontamination are described.

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This paper briefly reviews developments in liquid metal heat transfer in round tube that have been reported since Martinelli's theory was published in 1947. Recent progress in the knowledge of forced convection heat transfer to liquid metals flowing through various channels are discussed, to indicate the aspects calling for further research Nucleate pool boiling heat transfer is also taken up for its important position in basic heat transfer in boiling liquid metal. Particular attention is given to transient boiling.

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