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The purpose of this research is to highlight issues relating to binder migration in traditional lime mortars and the potential consequences of this phenomenon. The paper focuses on traditional mass masonry construction and will be of special interest to those surveying, maintaining and repairing historic ruinous structures and heavily exposed masonry bridges.

The paper draws on literature pertaining to the repair of traditional mass masonry structures and the somewhat limited science of binder dissolution and migration in saturated conditions. The paper also draws on the author's practical and academic knowledge of writing specifications for the repair of mass masonry structures and utilises examples of binder migration from several case study buildings.

The degree to which binder migration in traditional mortars occurs is little understood. It is, however, evident that migration of the binder occurs when saturated conditions are present and is exacerbated by prolonged moisture ingress. The effect of binder migration on the stability and performance of mass masonry structures is also little understood and requires greater attention. In addition, the nature of the repair mortars specified and the degree to which these materials have set will have a bearing on the potential for binder migration.

An assessment of binder migration in traditional lime mortars and its effect on the stability and performance of mass masonry structures has never previously been undertaken. This paper is the first to highlight the problem.

STEEL Anti‐corrosive carbonate layer. Calcium bicarbonate, which is present in virtually any natural water, suppresses the corrosion of steel if it is allowed to form—together with corrosion products—a coherent adhesive layer of calcium carbonate on the steel surface. The deposition of such a layer depends on the flow and the temperature of the water as well as on the concentration of calcium bicarbonate. Recent Czechoslovak work has been concerned with the use of radioactive calcium‐45 in the study of the influence of these factors on the formation of protective calcium‐carbonate layers in cold and warm water with low calcium bicarbonate content.

Introduction The sulphonate molecule has become one of the most versatile surface active chemicals available to industry. Its value as rust or corrosion inhibitor in a variety of areas has been demonstrated many times over in field and laboratory tests. A review of these various applications has been published.

A general review of the manufacture, properties, and uses of calcium stearate appeared in 1984. Its uses include that of a flating agent in paint, a lubricant, plasticizer and leveler for paper coatings, suspending agent in paints, a release agent in plastic and other mouldings, a tabletting agent, a water repellant, and a cosmetic component, etc. Methods for the production of the stearate have been published, e.g. from calcium hydroxide, in the presence of zeolites, as dust free granules, in spherical particles (for use as a stabilizer in poly (vinyl chloride), and as an aqueous surfactant, viscosity stabilized dispersion. The drying of the soap has also been described. Calcium/zinc stearate binary mixtures have been prepared, and calcium stearate dihydrate.

Phosphonic acids are good complexing agents. However, they are not good as inhibitors except for a very few. Synergistic inhibition is offered in the presence of metal cations like Ca²⁺, Mg²⁺, Zn²⁺ and others in neutral media. The zinc ion is an ideal choice. The part of zinc ions are now replaced by polymers, azoles to prepare eco‐friendly inhibitor formulations. They are also used as corrosion inhibitors in concrete, coatings, rubber blends, acid cleaners, anti‐freeze coolants, etc. Discusses the various applications of phosphonic acids and their action mechanisms.

The purpose of this paper, an R&D project, is to select Globally Harmonized System of Classification and Labeling of Chemicals (GHS)-unclassified white solid lubricants for formulating special lubricating oils, greases and pastes to prevent tribological systems against fretting wear.

The scientific methodology reads as follows: market research to select appropriate additives according to the purpose of the R&D project; screening tests to determine the technical performance of the additives; advanced technical studies and tests to validate the technical performance of the lubricating additives; determination of the reaction layers; and clarification of the build-up mechanism of the reaction layers (practical tests).

The findings of the R&D project can be summarized as follows: the selected white solid lubricants perform in lubricating oils, greases and pastes highly effective against fretting wear. The performance could be shown on the basis of representative test results and highlights its advantages compared to the state of the art.

The research team faced some challenges during the R&D project – the unsuitability of standard test measurements as well as DIN, ISO and ASTM test parameters led to limitations and increased effort.

The motivation and main target to conduct the R&D project was to increase the consumer and operator safety by using unclassified (GHS) high performance lubricants. The findings of the project show clearly that the tasks could be fulfilled. Special, unclassified (GHS) selected white solid lubricants are able to form a reaction layer on metal surfaces and separate effectively the surfaces within the tribological system. No fretting wear accrued. The consumer can gain substantial benefits on the economical side as well as on the ecological side.

In hard‐water areas little or no corrosion trouble is experienced in chilled water systems used in dairies, for cooling platens in plastic presses, for cooling air in air‐conditioning systems, etc. In soft‐water areas, serious corrosion has been experienced. Attempts at corrective treatment through synthesis of hard water in soft‐water areas were only partially successful. However, considerable success is reported with a new powder inhibitor.

This paper seeks to synthesize needle‐shaped anticorrosion pigments based on the ferrites of Zn, Ca and Mg for metal protecting paints.

Anticorrosion pigments were synthesized from oxides or carbonates at hot temperatures. The following pigments were synthesized: ZnFe₂O₄, MgFe₂O₄, CaFe₂O₄, Mg_0.2Zn_0.8Fe₂O₄, and Ca_0.2Zn_0.8Fe₂O₄. The prepared pigments were characterized by means of X‐ray diffraction analysis, by measuring the distribution of particle size and by means of scanning electron microscopy. The synthesized anticorrosion pigments were used to formulate epoxy coatings with PVC = 10 per cent for the synthesized pigment and with the PVC/CPVC ratio = 0.3. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with aluminium zinc phosphomolybdate.

The needle‐shaped particles were identified in the formulated pigments. It was found that all of the synthesized pigments had high anticorrosion efficiency comparable with that of Zn‐Al phosphomolybdate. The needle‐shaped particles markedly contributed to the advancement of the physical‐mechanical properties of epoxy coatings.

The synthesized pigments can be conveniently used in coatings protecting metal bases against corrosion.

The application of the synthesized pigments with the needle‐shaped particles in anticorrosion paints protecting metals presents a new method. The benefit of the application and method of synthesizing anticorrosion pigments is that they do not contain heavy metals and are acceptable for the environment.

The statement of the Minister of Agriculture, Fisheries and Food, coming so quickly after the ban on the use of cyclamates in food and drink in the United States, indicates that the new evidence of carcinogenesis in animals, placed at the disposal of the authorities by the U.S. F.D.A., has been accepted; at least, until the results of investigations being carried out in this country are available. The evidence was as new to the U.S. authorities as to our own and in the light of it, they could no longer regard the substances as in the GRAS class of food additives. It is, of course, right that any substance of which there is the slightest doubt should be removed from use; not as the result of food neuroses and health scares, but only on the basis of scientific evidence, however remote the connection. It is also right that there should always be power of selection by consumers avoidance is usually possible with other things known to be harmful, such as smoking and alcohol; in other cases, especially with chemical additives to food and drink, there must be pre‐knowledge, so that those who do not wish to consume food or drink containing such additives can ascertain from labelling those commodities which contain them.

In broad terms the object of every engineer operating oil burning plant has always been to obtain the maximum amount of effective B.Th.U.s for every pound of oil burned. Recently, however, it has been established that as the thermal efficiency of modern high pressure, high temperature oil burning plant has increased there has been a similar increase in corrosion. The extent of this problem is due to the fact that currently available residual fuel oils contain inorganic substances, amongst them vanadium, sodium and sulphur. If these substances were not present hydrocarbon petroleum oils would merely be burned to yield carbon dioxide and water.