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The purpose of this paper is to outline the electrochemical noise method as a way of evaluating quickly (screening) coatings formulations in the laboratory. The standard configuration requires two test specimens and a reference electrode. Equipment is relatively inexpensive and is computer controlled. Data analysis is quite simple but to improve accuracy some treatment of the plots may be necessary. Some previously published results for application to water‐borne coatings both intact and when scratched are reproduced here to illustrate the method. Comparison has been made with DC techniques. Application of the method to detached coatings is included.

This work investigates the single substrate (SS) technique for obtaining potential and current noise data for electrochemical noise measurement (ENM) analysis. The technique uses a single substrate element, and has shown promise as a useful application for use in the field. The traditional two working electrode approach of obtaining data is hindered by the fact that two electrically isolated substrate elements are required to act as working electrodes. The SS technique addresses this problem, theoretically enabling ENM to be made on any structure using just one electrical connection to the metallic substrate. Results are presented for anti‐corrosive organic coating systems intended for marine applications that have very high resistance values (> 1 × 10⁹ohm‐cm²). In addition data obtained from previous work that looked at a single coat anti‐corrosive primer after a short period of time in immersion and giving R_n values of around 1 × 10⁸ohm‐cm² are presented. Good agreement is seen between values of R_n obtained from the traditional two working electrode method and those obtained from the single substrate technique over both ranges of resistance.

The use of CO₂ as a replacement for conventional air in combustion gas streams of gas turbine power‐generation equipment is a novel idea and a potential method of providing an almost pure CO₂ stream for subsequent disposal/sequestration. The purpose of this paper is to investigate the effects of this novel gas environment on conventional gas turbine component part materials over the same range of temperatures found in service.

Test samples of candidate materials were tested in simulated environments using controlled gas and steam supplies to sealed horizontal laboratory furnaces. Conventional weight change tests, metal loss tests and electron microscope examination were used to assess the performance of the materials and compare the oxidation morphology. Spectra of the oxidation products were also used to determine the nature of the oxides formed on selected materials.

It is found that changes in the percentage of steam in the novel gas environment made little difference to the performance of the selected alloys. However, when the results of the program are compared with typical data from previous works, where the same alloys are exposed in air, there is a distinct trend. Comparison between the data from air exposed samples and data from those in this paper show the high CO₂ environment, envisaged for the GAS‐ZEP concept, to be more aggressive to all of the alloys tested.

This paper describes the first investigation into the performance of candidate materials for the various components around a GAS‐ZEP system in the novel operating environments anticipated. The work has shown that current power plant materials can be considered for use in first generation GAS‐ZEP systems, but that care is required in their selection at the higher operating temperatures.

It has been generally assumed that, although there may be material costs to the entire world which result from any attempt to eliminate global poverty through development, the only costs associated with the continued existence of poverty are human ones, costs which are borne primarily by the poor themselves. This article is a review of the literature on development and resource use; its primary purpose is to investigate the extent to which analysts have tested this assumption—that is, the extent to which they have addressed the issue of the material costs engendered by the perpetuation of global poverty. Its conclusion is that no systematic analysis of this assumption has been conducted. However, there is a recognition of the resource costs of global poverty implicit in much of the literature on development and on resource use, and there is sufficient evidence to indicate that more detailed study of the relationship is warranted, since it is clear that the continued acceptance of global poverty entails significant costs for every member of the global community.

The Minister of Agriculture and Fisheries, the Minister of Food and the Secretary of State for Scotland, appointed a Working Party in May, 1951, “to examine the present structure of producers' prices for milk and to advise whether it is desirable and practicable to make revisions which would promote an improvement in the composition and quality of milk sold off farms in the United Kingdom”. The Working Party has now issued a Report (H.M.S.O.).

This research aims to study the influence of limestone filler on rebar corrosion.

Mortar samples containing 35% calcareous filler and with a rebar inserted in the axis, were cast. Specimens were cured at the open air and during 28 days in lime water. After curing, they were submerged in two electrolytes (tap water and 3% NaCl) and corrosion parameters (corrosion potential and corrosion current) were monitored over time by d.c. techniques. Simultaneously, electrochemical noise measurements were carried out. After corrosion tests, rebars were pulled out by lateral compression, and their surface observed by scanning electron microscopy.

In general, carbonate additions impaired mortar protective properties, especially in the presence of chloride and changed the nature of the protective layer on rebars. The curing process did not introduce significant differences except for mortars with a high water cement ratio cured in lime water for which the beneficial effects of the simultaneous presence of carbonate and lime in the pore solution could be appreciated. The role of carbonate additions is to provide carbonate anions to passivate rebars. This passivation process caused corrosion rates not to be so high. Carbonate anions also deposited on oxide spots which were rendered passive but this process was not uniform. Certain areas on the rebar underwent intense carbonation while others showed increased corrosion rates.

There are not many corrosion studies about the influence of limestone filler on rebars corrosion. Particularly, this paper deals with mortars containing high percentages of carbonate additions. Results showed that the presence of this type of admixture changes the structure of the passive layer and, sometimes, may increase corrosion rates.