In the Engineering School a new and improved distillation apparatus for moisture determination was designed and tested, and it was shown that the conventional oven drying method for the determination of moisture in brown coal gives results which are on the average of 1%
lower than those obtained by the distillation technique.
The results of the sampling showed that under normal conditions of brown coal usage, the moisture content changes by only a few per cent from mine to furnace. Further, the variation of moisture content of samples of coal from the same source was surprisingly low. It was also found that the size of samples to be taken from a batch of brown coal for a specified sampling accuracy increases as the storage period of the coal increases.
(4) The Oxidation of Brown Coal Worker : Mr. J. M. Crennan.
The programme of investigation was arranged to provide information on the rates of oxidation of three different Victorian brown coals under various conditions. The coals used were from Yallourn North, Yallourn Open Cut and Bacchus Marsh. Samples were tested both in the raw state and also after Fleissner drying, the drying having been done under different conditions of steam temperature and rates of heating and cooling.
The coals were allowed to oxidize at atmospheric pressure in an atmosphere of air, the oxidation taking place at two different tempera- tures, namely 20°C and 37°C. Two sizes of coal were used, the larger passing a â" sieve and being retained on a $" sieve, and the smaller about one eighth this size.
Seventy-two tests in all were carried out, the results being still in process of examination.
the liberation, comminution and concentration of valuable minerals mined in Australia. Particular attention is being paid to the beneficiation of beach sands from coastal regions in Southern Queensland and Northern New South Wales. Selective flotation of zircon has been accomplished successfully and much valuable information obtained on the possibilities of electrostatic concentration of zircon and rutile, valuable minerals of zirconium and titanium respectively. This work has been described in published C.S.I.R.O. reports. Twenty-four other reports on a wide variety of other mineral beneficiation problems were issued during the twelve months.
B. CHEMICAL METALLURGY
(2) Fundamentals of the Cyanide Process Workers : Messrs. G. M. Willis and T. Mills.
Electrochemical studies of gold in cyanide solutions have been con- tinued, particular attention being paid to the influence of the degree of alkalinity of the solution and the effect of solutes likely to be met with in the actual cyanidation of gold ores. The pH and adsorbable anions have been shown to exert marked effects ; the former determines the electrode potential range over which an oxide film may exist on the gold, while the latter hinder the formation of such a film. Much interesting information on the nature of surface films on silver and gold has been obtained and further work has been conducted on ionic equilibria in cyanide solutions.
(3) Electro-deposition of Metals
Workers: Messrs. G. M. Willis and T. Mills.
A. study of the cathodic deposition of metallic ions has revealed that for many metals a monatomic layer Of metal is first deposited on the surface being plated ; production of "normal" metal then follows, in some cases with a further unstable state which is interpreted as the- production of crystal nuclei.
(4) Slag-metal reactions Worker : Mr. G. M. Willis.
Following a theoretical examination of the validity of the usual solution laws when applied to slags, experimental work has been initiated to study equilibria in some simple slag-metal systems. The first system to be studied is boric acid-silver. Many unexpected phenomena have been observed in this work and a major campaign involving this and other systems is planned for 1949.
C. PHYSICAL METALLURGY
(5) Preferred Orientation and Strain Effects in Metals and Alloys Workers : Mr. J. S. Bowles and later Dr. R. L. Kamm, Mr. R. Smith
and Mrs. J. J. Birrell.
With the departure of Mr. Bowles for the University of Chicago about the middle of 1948 the work on the quantitative determination of the degree of preferred orientation in cold worked and annealed metals was brought to a close, but other members of Staff have continued to develop X-ray and other apparatus for the study of the effects of
orientation and degree of strain in metal crystals. The delay in delivery of apparatus from overseas has inhibited progress in some aspects of this work but a start has been made on the determination of the effect of the degree of preferred orientation of grains on the corrosion-cracking of rolled copper and brass.
(6) The Properties of Dilute Alloys of Lead with Sulphur, Selenium and Tellurium
Workers : Professor H. K. Worner and Mr. H. C. Coe.
A general preliminary investigation of the primary crystallization, work hardening, recrystallization and creep characteristics of these alloys has revealed the remarkable effects which may result from additions of very small percentages of the Group 6B elements to lead. The creep characteristics are particularly sensitive to minute changes in composition and/or prior treatment of the alloys. Remarkable effects have been noted in lead-sulphur alloys with as low as 0.001% by weight of sulphur and it has also been demonstrated that the condition of the selenium and tellurium in the lead can markedly affect the behaviour of the alloy during rolling or under prolonged steady stresses. An explanation is now forthcoming for the discrepancies in published information on the behaviour of tellurium leads in chemical industry. Further researches are planned on these alloys in the belief that they may provide a clue to the mechanism of deformation and cracking during the creep of metals and alloys.
METALLURGICAL RESEARCH The Baillieu Laboratory
Head of Department : Professor J. N. Greenwood.
(1) Behaviour of lead under prolonged stresses Worker : Professor J. N. Greenwood.
Further study has been carried out on the behaviour of lead and its dilute alloys under constant loads which are just sufficient to produce a very slow rate of flow or creep over prolonged periods of time. The problem is of importance in connection with the stability under stress, not only of lead but of metals in general. The process of creep is highly sensitive to small differences in physical condition of the metal, and during the year work has been carried out with a view to controlling these initial conditions so that the effect on the creep of introducing small amounts of specific alloying elements might be studied systematically.
(2) Strength of Metals
This is a general attack on the problem of the changes in atomic structure associated with the deformation and fracture of metals and associated processes. The work falls into separate provinces, each of which is studied mainly by the following workers, under the general direction of Dr. W. A. Wood. The various fields are as follows:—
(a) Creep of Metals Worker : Mr. G. R. Wilms.
Mr. Wilms has examined the changes in structure as pure aluminium is subjected at elevated temperature to loads which produce slow con-
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tinuous deformation. Using X-ray diffraction and metallographic methods of examination, he has discovered and elucidated the main features of a new mechanism of deformation which apparently supersedes the normal mechanism as the temperature of deformation is increased and the rate of deformation at any one temperature is decreased. The results are likely to open a new approach to the practical problem of the strength of metals at elevated temperatures.
(b) Metals under constant rate of strain Worker : Mr. W. A. Rachinger.
Mr. Rachinger has studied the changes in structure of metals forcibly extended at fixed rates of strain at various temperatures. He has shown that the metallic grain dissociates into elementary units of structure and that the size of the units determines the resistance to deformation or the strength of the metal. The isolation of this unit and the observations on the manner in which its characteristics vary with conditions of deformation constitute a notable contribution to the general understanding of the mechanical properties of metals.
(c) Recovery and recrystallisation Worker : Mr. J. Ramsey.
The disruption and distortion produced during deformation of the metallic grain render the atomic structure somewhat unstable, and at some temperature on heating the structure undergoes a process of recovery and recrystallisation. Mr. Ramsey has investigated the factors determining the instability of the structure, and by means of X-ray diffraction methods has made some new observations on the intermediate changes prior to recrystallisation of the structure which suggest a likely solution of this long standing problem.
(d) The elasticity of metals Worker : Mr. R. Scrutton.
The property of elasticity in metals, viewed on an atomic scaler normally involves merely the reversible displacement of the atoms from their normal positions under the action of external stress. Using the technique of X-ray diffraction, Mr. Scrutton has measured the actual atomic displacements under systematically applied stress for a number of metals. The results are of fundamental interest in bringing to light the metal and these are likely to modify previously accepted views on anomalous atomic movements in the presence of plastic deformation of the mechanism of elasticity.
(e) Fatigue of metals
Workers: Dr. W. A. Wood, and Mr. A. Head (C.S.I.R.O.).
The behaviour of metals under alternating stresses raises new problems in connection with modern developments of high speed mechanisms.
The properties of metals under such conditions, which lead to the so- termed process of failure by fatigue, are being studied in the conjunction with C.S.I.R.O. The immediate object has been to find the manner in which the atomic structure responding to alternating stresses differs from the behaviour under normal static stresses. Preliminary experiments have indicated one fundamental difference which is likely to prove of particular significance.
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(3) Constitution and Properties of Lead-sodium Alloys Workers : Professor J. N. Greenwood and Mr. D. Davies.
The work commenced in previous years on this problem has been continued and it appears likely that the various anomalies in hardness and electrical resistance reported upon earlier will be resolved. These particular alloys have raised interesting fundamental questions which it is hoped soon to make the subject of a final full report.
(4) The properties of titanium and its alloys
This work is being carried out by members of the C.S.I.R.O. staff associated with the Department (Mr. A. D. McQuillan and Mr. H. W.
Worner). Titanium ores are found to an appreciable extent in Australia and there is widespread interest in the potentialities of the metal. A study has been made of the physical properties, and techniques developed whereby the metal may be fabricated. A special investigation of the allotropic changes in atomic structure produced on heating has led to new and interesting data which will have an important bearing on the constitution of possible alloys. A further branch of the work has been directed to a preliminary survey of the solubility ranges of added elements and the properties of the alloys.
(5) The properties of tantalum and its alloys Worker : Dr. R. H. Myers.
The work has covered the preparation of tantalum powder from tantalite ore, the production of the solid metal by sintering of the powder, fabrication of the metal and study of its mechanical and physical properties. Interesting properties of the metal and some of its alloys have been found, and development of further alloys was under considera- tion. But with the resignation of Dr. Myers during the year and in view of limitations to staff it has been necessary, unfortunately, to discontinue the project.
METEOROLOGY
Head of Department : Dr. F. Loewe.
(1) Annual Trends of Variability of the Meteorological Elements in the Southern Hemisphere
This work commenced by Dr. Loewe in 1946 is now completed and is being published by the Commonwealth Meteorological Bureau.
(2) Antarctic Studies
For the first months of the year under report, Dr. Loewe was a member of the Wyatt Earp during its antarctic cruise. Some meteoro- logical and glaciological notes resulting from the cruise await publication, and work on the observations continues.
(3) Atmospheric Studies
Dr. Loewe and Mr. U. Radok studied vertical structure of the atmos- phere and the structure of gusts with the aid of soaring planes. Mr.
Radok has almost completed his thesis for the degree of Doctor of Philosophy on Upper air conditions over Australia from radiosonde flights and continued his studies of atmospheric gusts.
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(4) Meridional Cross Section through Southern Hemisphere
Dr. Loewe and Mr. Radok established the first comprehensive meridional cross section through the southern hemisphere from equator to pole. The results await publication.
OBSTETRICS
Head of Department : Acting Professor Johnstone.
(1) Incidence of Tuberculous Endometritis in pelvic and abdominal tuberculosis
Worker : Dr. S. L. Townsend.
Investigations in this field are in progress.
PATHOLOGY
Head of Department : Professor P. MacCallum.
(1) Sarcoidosis
Workers : Dr. A. W. Pound and Dr. Bruce J. Robinson.
Research into the condition of sarcoidosis has continued from the clinical, radiological and pathological aspects.
Clinically, a number of new cases was studied and a considerable amount of material collected which will ultimately be used in the publi- cation of articles.
Results of the survey revealed that a significant proportion of patients with this condition had had close contact with cases of tuberculosis and suggest that an adequate survey of close contacts of these patients would prove of value.
From the pathological viewpoint attempts were made to isolate a causative organism by methods of culture and animal inoculation.
Although these have generally proved negative the significance is not yet clear.
Investigations are being made on the problem of the nature of tuber- culin sensitivity, its mechanism and role in the pathogenesis of tuber- culosis.
(2) Diseases of Lymph Nodes Worker : Dr. J. D. Hicks.
Over five hundred lymph glands have been cut and various slides stained by normal and special Silver methods. Many have been described in detail and are being classified. The clinical records of these cases are being abstracted in an attempt to correlate the morphology with the clinical manifestations of the disease.
The effect of subcutaneous implantations of Stilboestol in rats, which were killed at increasing intervals, is being studied by histological exami- nation of the regional lymphoid tissue.
(3) Surgical Pathology of Ear, Nose and Throat Worker : Dr. T. G. Swinburne.
An investigation is being undertaken, with the co-operation of the medical staff in the Ear, Nose and Throat Department of the Royal Melbourne Hospital, into the aetiology and treatment of Menière's
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Symptom Complex—an attempt being made to classify cases according to their histamine skin sensitivity and on the basis of this to test the effect of treatment.
(4) Lung Changes in Rheumatic Heart Disease Worker : Dr. K. J. Grice.
Sections of lungs from twelve cases of rheumatic heart disease were examined but no conclusions could be drawn from changes seen. Collec- tion of material and investigation is being continued.
(5) Tuberculosis Survey Worker : Dr. A. W. Pound.
The survey of medical students' reactions to tuberculin at various phases of their course has been continued.
PHILOSOPHY
Head of Department : Professor A. B. Gibson.
A. INVESTIGATIONS BY RESEARCH SCHOLARS