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The name of H. H. Uhlig and the work of the Corrosion Laboratory at M.I.T. are synonymous and familiar to corrosion engineers throughout the world. We are fortunate this month in being able to publish an article describing the corrosion researches at M.I.T., from the pen of Professor Uhlig himself. Research on corrosion has been pursued at M.I.T. since the turn of the century, always on fundamental corrosion phenomena. As Professor Uhlig says at the end of his article, “money spent by industry or Government on basic corrosion research probably marks one of the soundest investments of present times”—the following gives a very good idea of what this has entailed at M.I.T.

To analyze the different approaches used to estimate the cost of corrosion and understand the limitations so as to have proper appropriation in future appraisals.

Four well‐known approaches to analysis of cost of corrosion viz., the Uhlig method, the Hoar method, NBS‐BCL input/output method and net present value method have been considered in great detail and the impact of these approaches on corrosion economy in different countries has been highlighted.

Uhlig method of estimating corrosion cost always gives a conservative estimate of the direct cost of corrosion. The direct cost of corrosion, as estimated by the Hoar method, is found to be somewhat higher than is the estimate made using the Uhlig method, as shown by Shibata of Japan. The NBS‐BCL method of input/output analysis, though apparently more scientific, is subject ultimately to uncertainties in quantifying the capital cost and intermediate output. The net present value method appears to be more realistic than do other approaches as it enables a life cycle costing of each structure/facility to be made and arrives at the most cost‐effective corrosion control method. Even though all the above four approaches enable an estimation of direct cost of corrosion, there is no standard approach to assess the indirect cost of corrosion.

In a developing economy, each and every industry has to go for systematic corrosion auditing in order to identify and adopt the most appropriate corrosion control measures and effect considerable savings. This paper would be of immense use in that regard.

The recent financial and sovereign debt crises around the world have sparked a growing literature on models and empirical estimates of defaultable debt. Frequently households and firms come under default threat, local governments can default, and recently sovereign default threats were eminent for Greece and Spain in 2012–2013. Moreover, Argentina experienced an actual default in 2001. What causes sovereign default risk, and what are the escape routes from default risk? Previous studies such as Arellano (2008), Roch and Uhlig (2013), and Arellano et al. (2014) have provided theoretical models to explore the main dynamics of sovereign defaults. These models can be characterized as threshold models in which there is a convergence toward a good no-default equilibrium below the threshold and a default equilibrium above the threshold. However, in these models aggregate output is exogenous, so that important macroeconomic feedback effects are not taken into account. In this chapter, we (1) propose alternative model variants suitable for certain types of countries in the EU where aggregate output is endogenously determined and where financial stress plays a key role, (2) show how these model variants can be solved through the Nonlinear Model Predictive Control numerical technique, and (3) present some empirical evidence on the nonlinear dynamics of output, sovereign debt, and financial stress in some euro areas and other industrialized countries.

Passivity and localized corrosion is discussed using iron, iron‐chromium, iron‐chromium‐nickel alloys and aluminium as examples. A brief description is given of the prevailing ideas regarding the nature of the passive film and the processes by which its protective properties are lost when breakdown of passivity and localized corrosion occurs.

This is a slightly shortened version of a paper presented at the symposium on corrosion held in the University of Melbourne late last year. Prof. Worner presided over the meetings which succeeded in directing the attention of many industrialists to the dangers of corrosion. In this paper some interesting aspects of corrosion costing are given, with particular application to Australian industry, and we feel that the information given here is an important addition to the not over‐prodigious amount of literature available on the subject of corrosion costs.

In this chapter, the authors ask two questions: (i) Is the conduct of monetary policy stable across time and similar across major economies? and (ii) Do policy decisions of major central banks have international spillover effects? To address these questions, the authors build on recent semi-parametric advances in time-varying parameter models that allow us to increase the vector autoregressive () dimension and to jointly model three advanced economies (USA, UK and the Euro Area). The main reduced-form finding of this chapter is an increased connectedness between and within countries during the recent financial crisis. In order to study policy spillovers, we jointly identify three economy-specific monetary policy shocks using a combination of sign and magnitude restrictions. The authors find that monetary policy shocks were larger in magnitude and more persistent in the early 1980s than in subsequent periods. The authors also uncover positive spillover effects of policy between countries in the 1980s and diminished, and sometimes negative ‘beggar-thy-neighbour’ effects in the second half of the sample. Moreover, during the 1980s, the authors find evidence for policy coordination between the Federal Reserve, the Bank of England and the European Central Bank.

The purpose of this paper is to show a standard RBC model, when augmented with a VAT evasion channel, where evasion depends on the consumption tax rate, can produce a hump-shaped consumption-Laffer curve.

The methodology is in the spirit of modern quantitative macroeconomic literature.

The model with VAT evasion can generate a peaking consumption tax revenue curve, which is a little discussed result in the taxation literature.

The paper contributes to the public finance literature by providing evidence for the importance of the evasion mechanism, while at the same time adding to the debate about the existence of a peak tax rate for consumption tax revenue.

Contrary to popular belief, raising VAT rate as a cheap way (being a tax on demand) to finance government expenditure, is still not a free lunch, and raising the rate, especially in a country with substantial VAT evasion, quickly leads to a drop in the revenue associated with that category.

This is the first study that provides a tractable model of VAT evasion, and a setup where consumption tax revenue curve is peaking.

The effect of the addition of aggressive salts such as LiCl, NaCl, KCl, RbCl and MgCl2 on the steady‐state potential of a Zn electrode previously equilibrated in a passivating chromate solution is established. S‐shaped curves are obtained for the variation of the steady‐state potential with the quantity of aggressive salt added. For each inhibitor concentration, Cinh, the addition of aggressive ions up to a certain concentration has no effect on the passivity of Zn. However, higher Cl ion concentration causes destruction of the passive film and initiation of pitting corrosion. Destruction of passivity occurs after an induction period which decreases with the increase in the concentration of the attacking ion and/or the decrease in that of the inhibiting ions. The concentration of aggressive ion, Cagg, that can be tolerated by a certain concentration of the inhibiting ions, Cinh, is given by the relation : log Cinh =K + n log CCl−, where K and n are constants. The efficiency of these salts in initiating pitting corrosion increases in the order RbCl ≤ MgCl2, ≤ KCl < NaCl < LiCl. The change in the degree of aggressivity of these salts could be attributed either to the incorporation of the cations in the passive film or to their effect on pH.

The present study addresses the mutual relationship between pollution and corrosion in the context of the petroleum refining industry. The rate of galvanic corrosion of steel coupled with copper when immersed in oil refinery wastewater was studied by the weight‐loss technique. The variables studied were: MgCl₂ concentration, the ratio between the cathode area and the anode area of the galvanic couple, and operating temperature. It was found that the rate of galvanic corrosion of steel coupled with copper increased with increasing MgCl₂ up to a certain concentration and then remained almost constant with further increase in concentration. Increasing the cathode/anode area ratio also increased the rate of corrosion. The rate of corrosion increased with temperature at an activation energy of 8.4 kcal/mol, which denotes that galvanic corrosion of steel in MgCl₂ solution is a diffusion‐controlled reaction.

Corrosion and Corrosion Control, by Herbert H. Uhlig. The aim of this 370‐page book is well summarised by the sub‐title, i.e. ‘An introduction to corrosion science and engineering’. The author, a well‐known authority on corrosion subjects, has been in charge of the Corrosion Laboratory, Massachusetts Institute of Technology, since 1946, but his research work in this field began as far back as 1936.