Corrosion rate data for mild steel corrosion inhibitors in carbonated brine media were fitted to the Temkin adsorption isotherm. The fundamental constants of the Temkin adsorption isotherm, i.e., molecular interaction and adsorption equilibrium constants, were used to glean important information about the behavior of adsorbed corrosion inhibitors. Adsorption data were also used to calculate Δ ad H , Δ ad G , and Δ ad S , and the results demonstrated that some compounds are chemisorbed onto the electrode. Significantly, it has been found that chemisorption of corrosion inhibitors can yield very good film persistency (i.e.. corrosion protection even when the inhibitor is no longer present). Molecular modeling using the quantum mechanical program PCSpartan plus, along with a comparative analysis of adsorption data for a broad range of inhibitor molecules, has been used to derive a tentative structure/activity relationship for some oil field corrosion inhibitors. © 1999 The Electrochemical Society. All rights reserved.

Many readers will no doubt have already had an opportunity to see the earlier draft of this publication, which was circulated widely for consultation to a range of providers. It is a policy framework to guide the use of physical interventions (restraint) with adults and children with learning disability and/or autism, and is the result of collaboration between BILD and the National Autistic Society (NAS). Part of that process involved consultation at a number of stages, and the result is a document that should become required reading for all serviceprovidersbe they at the 'hands-on' level of provision, or at the policy and planning level of management.Physical interventions are defined as the actions by which one person restricts the movements of another, and which are maintained against resistance. Specifically such interventions embrace 'any method of responding to challenging behaviour which involves some degree of direct physical force to limit or restrict movement or mobility' (p. 2). This would include: direct physical contact, the use of barriers such as locked doors and the use of materials or equipment which restrict or prevent movement.The publication of this volume does not, I feel, reflect an increase in the use of physical interventions, but rather it takes account of an increasing awareness of the risks to service-users of abuse, and the need to ensure that their lives should be as positive as possible. At the same time BILD and the NAS have a realistic view of the many challenges that face service-providers, and indeed, how these pose risks to the care-givers also. Consequently this publication is timely in what it provides to those whose daily work involves close contact with people who present significant challenges, and to those who are commissioning those very services.The book is not directive, in the sense of indicating what must be done. Instead it highlights the need to have policies, procedures and guidelines. The aim has been not to provide an 'off the peg' formula, but rather to give an overview of the elements that need to be taken into account in developing a policy around physical interventions. This is achieved through the key areas of the law; a common values base; prevention of challenging behaviours; risk assessment; minimising risks and promoting the best interest of service-users; management responsibilities; employers' responsibilities towards staff; and staff training. Throughout, the structure of the book encourages the reader to question their own practice, the systems already in place and how these might be improved. Each section concludes with an Agenda for Action, having taken the reader through basic premises, examples of good and poor practice and checklists.I particularly like the layout, with 32 key statements that have been highlighted, and which draw the casual browser to read in more detail. For example: 164

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This paper presents a fundamental study of the influence of various chemical inhibitors on the corrosion rate of mild steel in brine electrolyte under carbon dioxide conditions. The corrosion inhibitors were fitted to a Temkin adsorption isotherm, and various fundamental constants of adsorption (i.e., adsorption equilibrium constants and molecular interaction constants) have been obtained. The inhibitor adsorption mechanism has been discussed in terms of thermodynamics (i.e., normalΔH, normalΔG, and normalΔSfalse), and this revealed that some compounds chemisorb onto the steel electrode. In addition, molecular modeling was undertaken using PCSSPARTAN Plus and HyperChem Professional, and the various molecular parameters have been correlated with the thermodynamic adsorption properties of the inhibitors. Three-parameter and four-parameter fits for both negative and positive models are discussed. Multiple linear regression was performed on various combinations of molecular descriptors to describe the enthalpies and entropies of adsorption. Similarly, principal component analysis (PCA) was employed to corroborate the scientifically based selection of molecular descriptors used in the multivariate regression models. © 2004 The Electrochemical Society. All rights reserved.

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