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In the industrial silylation process, the cost of production can be greatly reduced by reducing the frequency of the replacement of the silane solution. The purpose of this paper is to describe how a method of discontinuous addition of concentrated solution into the KH560 treatment bath was developed, to improve further the effective availability of the silane solution and reduce cost of production.

The preparation and addition of each incremental amount of concentrated KH560 was studied in detail.

The results indicate that adding concentrated silane solution is an effective method of maintaining the target bath concentration.

The paper describes how a method of adding concentrated KH560 was developed to prolong the working time of KH560 solution for silane coating production, and to improve the availability of the KH560 in solution. The results indicated that adding concentrated solution was an effective method of prolonging the working time of the silane solution. The mixture ratio of the concentrated solution, and the volume of each incremental amount, both affected the performance of the KH560 solution.

Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of plastics and metals such as zirconium, titanium and tantalum. Plastics are finding extensive use as lining materials for chemical plant operating at moderate temperatures, but the poor thermal conductivity of most plastics makes them unsuitable for the transfer of heat. The recently developed metals and their alloys are extremely expensive to produce and fabricate and, so far, their use has been confined to certain specialised applications, although full‐scale production of zirconium is being carried out in America, mainly because of the low capacity of the metal for absorbing thermal neutrons. At the moment, however, these metals, because of their high cost, cannot compete commercially on a large scale with the older well‐established corrosion‐resisting alloys such as the high‐silicon iron alloys. The excellent corrosion resistance of the high‐silicon iron alloys, even at high temperatures, and their high thermal conductivity have established them as almost standard alloys for acid concentration and cooling plant construction. The following article outlines their composition and properties.

Aqueous solutions which contain H2SO4, H2S or mixtures of H2S and NH3 are corrosive to carbon steel and other commonly used alloys. Therefore, titanium has been evaluated as a possible construction material in these environments. This paper summarizes the results of a study of the corrosion, galvanic and hydrogen embrittlement behaviour of titanium in aqueous sulfidic and sulfate solutions. Variables discussed include the effect of solution pH, temperature and solution composition on the corrosion and electro chemical behaviour including galvanic effects of titanium. This paper also considers the effect of pH, temperature and mechanical loading rate (strain‐rate) on the ductility and embrittlement of titanium.

This is indeed the age of revolution, when timeless attitudes are changing and new ways of living being born. To most it is a bewildering complex, with uneasy forbodirtgs of the outcome. Improvement and change, there must always be—although change is not necessarily progress—but with unrest in the schools, universities and industry, one naturally questions if this is the right time for such sweeping reorganization as now seems certain to take place in local government and in the structure of the national health service. These services have so far escaped the destructive influences working havoc in other spheres. Area health boards to administer all branches of the national health service, including those which the National Health Service Act, 1946 allowed local health authorities to retain, were recommended by the Porritt Committee a number of years ago, when it reviewed the working of the service.

In the following article the author discusses the present state of knowledge of this subject. He then deals with stress corrosion in plant using chloride or caustic solutions and plant using water or steam. Finally, the importance of stress corrosion is considered.

The purpose of this study is to determine the physicochemical and rheological parameters of Albizia lebbeck gum.

Physicochemical analysis was carried out using recommended methods. Gas chromatography mass spectrophotometer and Fourier transformed infra red (FTIR) analyses were carried out using their respective spectrophotometer. Scanning electron microscopy was carried out using scanning electron microscope, while rheological measurements were carried out using Ubbelohde capillary viscometer, digital Brookfield DV 1 viscometer and a rheometer.

Albizia zygia gum is an ionic gum with unique physical and chemical properties. Scanning electron micrograph revealed that the internal structure of the gum is porous with irregular molecular arrangement. Thermodynamic parameters of viscous flow indicated the existence of few inter- and intra-molecular interactions, and the attainment of transition state was linked to bond breaking. Coil overlap transition studies revealed the existence of dilute and concentrated regimes. The viscosity of the gum was also found to decrease with decrease in the charge of cation (such that Al3+ > Ca2+ > K+) and with increase in ionic strength.

The paper provided information on physicochemical and rheological characteristics/behaviour of Albizia zygia gum, of Nigerian origin. From this information, possible application of this gum in the food and pharmaceutical industries can be deduced.

The paper is original since information concerning Albizia zygia gum of Nigerian origin are not well documented as established in the work. It also adds values on the use of Albizia zygia gum, either on its own or in combination with other gums for industrial purpose.

The melt‐viscosity of shellac at various temperatures, the solution viscosity of shellac and the solution viscosity of several shellac‐based varnishes were investigated using a cone and plate rheometer. The study revealed information regarding yield stress (minimum force required for initiating flow) and thixotropic properties of shellac and shellac‐based materials. Such information will be useful for developing shellac‐based moulded articles and shellac‐based varnish compositions.

The pattern of prosecutions forfood offences has changed very little in the past decade. Compositional offences have rarely exceeded 5 per cent and, since the 1967 batch of regulations for meat products, are mostly in respect of deficient meat content. Food hygiene offences have also remained steady, with no improvement to show for all the effort to change the monotony of repulsive detail. The two major causes of all legal proceedings, constituting about 90 per cent of all cases—the presence of foreign matter and sale of mouldy food—continue unchanged; and at about the same levels, viz. an average of 55 per cent of the total for foreign matter and 35 per cent for mouldy food. What is highly significant about this changed concept of food and drugs administration is that almost all prosecutions now arise from consumer complaint. The number for adulteration as revealed by official sampling and analysis and from direct inspectorial action is small in relation to the whole. A few mouldy food offences are included in prosecutions for infringements of the food hygiene regulations, but for most of the years for which statistics have been gathered by the BFJ and published annually, all prosecutions for the presence of foreign matter have come from consumer complaint. The extent to which food law administration is dependent upon this source is shown by the fact that 97 per cent of all prosecutions in 1971 for foreign bodies and mouldy food—579 and 340 respectively—resulted from complaints; and in 1972, 98 per cent of prosecutions resulted from the same source in respect of 597 for foreign matter and 341 for mouldy food. Dirty milk bottle cases in both years all arose from consumer complaint; 41 and 37 respectively.

Analytical and numerical studies are conducted for two‐dimensional steady‐state coupled Marangoni and buoyancy convection of a non‐Newtonian power law fluid confined in a rectangular horizontal shallow cavity subjected to a horizontal temperature gradient between the two short vertical rigid sides, while the upper free surface and the lower rigid one are insulated. The results obtained by combining the two basic mechanisms (thermocapillarity and buoyancy) depend on whether their effects are aiding or opposite. The effect of the non‐Newtonian behavior on the fluid flow, the temperature field, and the heat transfer is studied. The parallel flow is obtained in some particular situations for which a good agreement is observed between the analytical results based on the parallel flow assumption and those corresponding to the numerical simulations.

Analytical and numerical studies are conducted for two‐dimensional steady‐state Marangoni convection of a non‐Newtonian power law fluid confined in a rectangular horizontal shallow cavity subjected to a horizontal temperature gradient between the two short vertical rigid sides, while the upper free surface and the lower rigid one are insulated. The effect of the non‐Newtonian behavior on the hydrodynamic stability, the fluid flow, the temperature field, and the heat transfer is studied. The parallel flow is obtained in some particular situations for which a good agreement is observed between the analytical results based on the parallel flow assumption and those corresponding to the numerical simulations.