A method of gas measurement in the volume range 10(-4) - 10(-8)cc utilizing Töpler gas transport and Pirani-Stern hot-wire manometer principles is described. Sources of error are discussed and methods of avoiding them are given.

1. X-ray and neutron diffraction studies were caried out on the crystal lattice of beryllium oxide annealed at 2000 degrees. 2. It was determined that neutron diffraction data confirms X-ray conclusions of the positions of beryllium atom positions in the crystal lattice of beryllium oxide. 3. From neutron diffraction data the values of the temperature fact B + 0.92 and the Debye characteristic temperature theta = 602 +- 13 degrees K were found.

Pressure drop and heat transfer in annular tubes have been measured. The surface of the inner tube was artificially roughened. The investigation covered a range of Reynolds numbers from 200 to 100,000. The maximum heat flux, directed from the inner tube to the fluid, was about 316 W/cm2 or 2.7 x 10(6) kcal/m(2) h. The heat transfer medium was water. The hydraulic diameter of the annular tube served as characteristic length in the dimensionless Reynolds and Nusselt number. The results of all experiments are presented in graphic form. Heat transfer and pressure drop increase with the degree of roughness and depend on the type and arrangement of the roughness elements chosen.

The possibilities of producing graphite impermeable to gases and liquids, and suitable for nuclear applications, are discussed. The physical properties of such graphites depend on the different sealing processes and starting materials developed especially for the purpose. In the development of reactor grade graphite, described in a previous article, Germany was well behind other countries. As far as the making of impermeable graphite is concerned, however, advanced processes for and experience in the manufacture of impermeable materials for the chemical industry were available here before the publication of other research in this field. Liquid -- and gas -- impregnation methods are discussed mainly. The problems of sealing and the degree of impermeability that can be obtained are shown using different measuring techniques. Finally, a description is given of "pyrographite", a newly rediscovered old graphite material.

1. The reaction between beryllium salts and salicylic acid was studied by the spectrophotometric method in the ultra violet portion of the spectrum. The optimum pH value for this process was found to be 9.0 to 9.5. 2. Two independent methods showed that beryllium and salicylic acid form a compound in the ration 1:2. The instability constant was determined for the a complex of the formula (Be OH Sal2)3- names (4.9 +- 0.6) x 10-18. 3. The stability of the complex and the availability of the reagents makes the reaction investigated a suitable one for analytical applications.

It has been shown by studying the possibilities for determining the constants in stepwise complex formation by the interaction of hydrolyzed metal ions and ligands, that in a vast number of cases the direct measurements of metal ion and ligand activities ae necessary. Complete formulae for calculation are given and the conditions which allow some simplifications are established.

EDTA is an eluant with many possibilities for analytical chemistry. The authors present the results obtained in the separation of carrier-free radioisotopes; separation of Ba, Sr, Y, La; preparation of 228(Ra) from thorium; separation of Ca, Sr, Ba, and Ra. All the results were obtained with Dowex 50.

Selenenoyl-2-acetone is much more suitable for the extraction of thorium from aqueous solutions than acetylacetone, which is extensively used for this purpose. The stability constants of thorium selenenoyl-2-acetoneates and the distribution coefficient of the extracted complex in the CHCl3-H2O system have a higher value than those of the acetylacetonates of this element.

The main difficulties of experiments on the influence of radiation on creep is metals are discussed. Some typical apparatuses for investigation by using natural sources, reactors, cyclotrons, etc., are described. These methods have resulted in relatively inaccurate measurements up to now. Therefore, the published results do not allow any statement of laws, but only tendencies. There is a surprising influence of charged particles on creep rate in spite of their low depth of penetration. The discussion of the results leads to the conclusion, that the temperature of the specimen, the stresses and the density of beam are very important. Two requirements are put forward if such researches are to be of technical importance and not only of theoretical interest.

The complex formation reaction between beryllium and aluminon was investigated for different values of pH. It was established that at pH between 4 and 5 a complex is formed containing the constituents in the ratio 1 : 1 . At a pH between 7 and 8 a complex is formed having a beryllium-aluminon ratio of 3 : 1. At pH 6 both complexes are formed . It is shown that the complexes can be distinguished optically and in other aspects. The colorimetric determination of beryllium with aluminon is made at pH 5. At this pH value the results obtained for the determination of beryllium are satisfactory and of sufficient reproducibility.

Methods and equipment are described whereby electrical pulses are recorded on magnetic tape in two different ways, using a commercial, single-track type deck, The first method is used to record count rate information regarding regularly or randomly occurring pulses. Random count rates up to approximately 2,000 per second can be directly recorded without serious dead-time loss. By the addition of a simple, high-resolution scale-of-4, the input count rate can be increased to approximately 20,000 per second. By the other method information about relative pulse amplitude as well as count rate is recorded. The usable amplitude analogue output corresponds to an input range of at least 7 to 1, with linearity of approximately 1 1/2 per cent of maximum amplitude. Amplitude resolution of 2 to 3 per cent is obtained over the upper 70 per cent of the range. Transistorized circuitry is described which enables the output pulses of the tape recorder to be analyzed by a Radiation Counter Laboratories Inc. 256 channel scaler-analyzer.

The numerical solution of the double P/sub 3/ equations in slab geometry, by a forward-elimination back-substitution process, is described and is illustrated by application to a slab self shielding problem and by comparison with the results obtained by analytical solution of the equations.

The equation for the H.T.G.C. reactor fuel costs developed previously in AAEC/TM141 has been modified and applied to "heterogenous" fuel systems. Fuel costs are reduced by 20-25 per cent in these systems relative to the "homogeneous" systems; these advantages arise from the longer life which may ben assumed for the unfueled beryllia and cheaper fabrication costs. The effects of reduced beryllia costs on fuel cycle costs are also examined.

A method is described whereby the density of a single crystal of beryllium oxide can be measured by suspending it in a dense liquid. The method is being used to measure radiation-induced changes in density and is sensitive to 1 part in 10(5). The absolute accuracy has not been established owing the lack of a suitable standard.

Kalberer and Rutschmann (Helv, Chim, Act, 44 : 1956, 1961) described a method of estimating quantitatively C-14 compounds on a paper carrier, for example chromatograms. The sample is combusted in oxygen, the C14O2 produced being absorbed in ethanolamine solution and counted by liquid scintillation techniques. However, errors occur where there are deviations from their experimental conditions, such as in counting equipment or weight combusted, owing to differing concentrations of dissolved oxygen in counting solutions. Those errors can be eliminated by scrubbing the ethanolamine absorption solutions with nitrogen before they are mixed with the liquid scintillant. Furthermore, by this additional step, the range of weights combusted can be extended form 130 - 200 mg to 0-200 mg.

Order-of-magnitude estimates of the fast neutron elastic scattering rate have been obtained to supplement metallurgical studies of the fast neutron damage in some small beryllium oxide-based dispersed fuel specimens. The elastic scattering rate for neutrons with energies above 0.1 MeV is shown to be of the the order of 30 per cent of the fission neutron release rate in the specimens, owing to significant fast neutron leakage. The ratio of the Be (n,2n) reaction rate to the fission neutron release rate in the specimens is of the order of only 6 per cent of its value for an infinite medium of beryllium oxide.

The results of unclassified experiments on the irradiation behaviour of BeO fueled with UO2 and (U,Th)O2 are summarized and discussed. The overall picture is still somewhat confused owing to the different experimental conditions used by different workers. A serious deficiency in most of the work is the failure to quote the energies of the irradiation neutrons and it is not clear whether the observed changes are due to fission fragment or fast neutron bombardment. The irradiation behaviour, in general, appears to be good up to fission doses of at least 5 x 10(20) fissions cm-3 of dispersion.

Modifications to the A.A.E.C.'s Siemens Diffractometer are described which enable precision lattice parameter determinations on single crystals. Analysis of the errors and consideration of results suggest that accuracies of about 1--2 parts in 10/sup 5/ are obtained on small beryllium oxide crystals. Details of alignment and measurement procedure are included.

A summary of the available literature on the development of the various processes for the separation of uranium and thorium from aqueous nitrate solutions is presented. Flowsheets are given corresponding to the various stages in the development of the Thorex processes.

Samples from possible zoolite bearing deposits have been tested for cation exchange capacity using batch and column experiments. The best material, Eagleton Quarry pink shale, was given more exhaustive column tests to determine the effect of mineral particle size, influent flowrate, and the presence of competing cations on caseium breakthrough. Diffusion of caesium ions through the mineral particle controls the ion exchange process. At the optimum size of (-30+36) B.S.S. the cation exchange capacity of Eagleton Quarry pink shale is approximately 60 meq/100g. With competing cations in solution the caesium breakthrough occurs after very small influent volumes have passed through the mineral bed and it was concluded that non of the minerals tested would be suitable for medium level radioactive waste treatment. A sample of clinoptilolite from Hector, California was also test for caesium selectivity.

Samples of vermiculite from Young River, W.A., and Kingaroy, Qld., have tested for cation exchange capacity using batch and column experiments. The better material, Young River vermiculite, was given more exhaustive column tests to determine the optimum particle size and to investigate its selectivity for caesium ions in the presence of higher concentrations of competing ions. At the optimum particle size of (-30+60) B.S.S. the cation exchange capacity of Young River vermiculite was approximately 70 meq/100g. With competing cations in solution caesium breakthrough occurs after a very small volume of influent has passed through the bed. It was concluded that neither of these vermiculite minerals would be suitable of medium level radioactive waste treatment.

The equipment described was designed for static displacement measurements with linear differential transformer transducers in applications requiring high sensitivity and low drift. The output from the circuit is display on a 10 mV f.s.d. potentiometric recorder and an a.c. back-off arrangement allows the same basic sensitivity up to 20 times full scale deflection. Weekly drift of the output is less than 0.1 mV which is equivalent to an input drift of 0.005 mV. For longer term measurements any drift due to valve aging etc. can be corrected by inbuilt self-checking facilities.

The diffusion length of thermal neutrons in beryllium oxide of effective density 2.86 g cm-3 has been measured as 29.9 +- 0.8 cm. Using published experimental values for the diffusion constant of beryllium oxide, a value of [sigma] a = 9.0 +- 0.5 mb is deduced for the effective 2200m/s microscopic absorption cross-section.

Data relating to the binary and ternary systems involving beryllium oxide are presented . The survey deals with all available literature up to December 1962.