Synthesis and Reactivity of Iron(II) Complexes with a New Tripodal Imine Ligand

A new tripodal imine ligand tris(2-(propan-2-ylideneamino)ethyl)amine (imine₃tren) was prepared in order to stabilize high valent iron-oxido complexes. Iron complexes were synthesized in template reactions from iron(II) salts, tris(2-aminoethyl)amine (tren) and acetone. Due to the reversibility of the imine formation, complexes with different ligands were obtained depending on the reaction conditions. Three complexes, [Fe(imine₃tren)(OAc)₂] ( 1 ), [Fe(imine₃tren)(OAc)]OTf ( 2 ) and [(imine₃tren)₂Fe₂(F)₂](SbF₆)₂ ( 3 ), could be synthesized and structurally characterized. However, reactions with hydrogen peroxide, iodosobenzene or ozone did not lead to any kind of “oxygen adduct” complex that could be spectroscopically observed.     

Book reviews

A Fourth Way? Privatization, Property and the Emergence of New Market Economies. Gregory S. Alexander & Grazyna Skapska (Eds). London, Routledge, 1994, xxiii + 336 pp., ISBN 0415906970 (HB), 0415906989 (PB)

From Public Housing to the Social Market. Rental Policy Strategies in Comparative Perspective. Jim Kemeny. London and New York, Routledge, 1995, 194 pp., £40.00

European Housing Finance. Single Market or Mosaic?. Will Bartlett & Glen Bramley (Eds). Oxford, The Alden Press, School for Advanced Urban Studies (SAUS) publication 12 (Bristol) 1994, 282 pp., £19.95, paperback, ISBN 1 873575 63 7

Housing, Financial Markets and the Wider Economy. David Miles. Chichester, John Wiley & Sons, 1994, 228 pp., £35.00

Women in the Housing Service. Marion Brion. London, Routledge, 1994, ISBN 0 415 08094 £45.00 Hardback

Slippery Customers: Estate Agents, The Public and Regulation. Michael Clarke, David Smith & Michael McConville. London, Blackstone Press, 1994, 295 pp., £19.95     

Who lives downtown? Neighbourhood change in central Halifax, 1951–2011

The paper traces neighbourhood change in central Halifax, Canada, from 1951 to 2011 to consider how urban renewal policies and other factors may have influenced who lives downtown. In the 1950s planners advocated slum clearance and modernization to permit commercial expansion in the city centre. Subsequent decades saw central neighbourhoods decline. By the 1980s population began to rebound as planning policy increasingly promoted residential uses downtown. Over the 60 years central Halifax transitioned in character: three of the central tracts became increasingly affluent, while the fourth went from close to the city average to a low-income tract. The trajectories that neighbourhoods follow depend on several factors including societal changes, economic conditions, public policy interventions, and decisions made by other significant institutions (such as universities).     

The electrification accelerator: Understanding the implications of autonomous vehicles for electric utilities

The intersection of autonomous vehicles, ride sharing and transportation electrification could have significant implications for electric utilities. This paper analyses how the development of shared autonomous electric vehicles may make electrified transportation more likely and why this may lead to a more rapid than expected shift in the current transportation paradigm. We also discuss how these trends may affect utilities and suggest what they can do to prepare for the transition.     

Bio-derived sodium silicate for the manufacture of alkali-activated binders: Use of bamboo leaf ash as silicate source

Alkali activated binders are a promising alternative to the use of Portland cement in the manufacture of concrete for curbing CO₂ emissions. Novel sources of silicates have been investigated in recent years for reducing cost and environmental impacts associated with the use of chemical activators. This study describes the production of solid sodium silicate (SS) activating powder from bamboo leaf ash (BLA). Bamboo leaves were calcined at 550–800°C, mixed with NaOH pellets, and heated in an oven at 300°C. The obtained silicate powder was used for activating blended fly ash/slag samples. Mechanical and microstructural properties of BLA-based samples were compared to those of samples made with commercially available chemicals. The strength of BLA-activated mortars matched the commercially-sourced activators, being 25–30 MPa at 7 days and exceeding 40 MPa at 28 days. The microstructural analysis suggested that BLA-based SS showed a lesser degree of dissolution of precursors at 7 days, but the quality of the matrix was higher than that of NaOH-activated samples. These results confirmed that the reactivity of BLA-silicate powder was similar to that of commercial SS solutions, and show the potential valorization of future biomass renewable waste in the production of low carbon, alkali-activated concretes.     

Moderators and mediators of the stress-aggression relationship: Executive function and state anger.

The present study examined the effects of executive function (i.e., EF) and anger/hostility on the relationship between stress (across individual stress domains, as well as at the aggregate level) and aggression. Two independent groups of participants—a college sample and a low-income community sample—were administered a battery of self-report measures concerning the subjective experience of stress, aggressive behaviors, and feelings of state anger and hostility in the last month, along with a battery of well-validated neuropsychological tests of EF. Across both samples, the stress domains that demonstrated the strongest associations with aggression were those involving chronic strains of daily living (e.g., job, financial, health) versus interpersonal stressors (e.g., family, romantic). In the community sample, analyses also revealed a significant interaction between perceived stress (aggregated across domains) and EF in predicting aggressive behavior. Specifically, participants with relatively low EF abilities, across different EF processes, showed a stronger relationship between different domains of stress and aggression in the last month. Similar effects were demonstrated in the college sample, although the interaction was not significant. In both samples, experiences of anger and hostility in the last month mediated the relationship between perceived stress (aggregate) and aggressive behavior among those low, but not high, in EF. These findings highlight the importance of higher-order cognitive processes in regulating appropriate affective and behavioral responses across different types of individuals, particularly among those experiencing high levels of stress. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

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