Iridium(III) N-heterocyclic carbene complexes: an experimental and theoretical study of structural, spectroscopic, electrochemical and electrogenerated chemiluminescence properties

Four cationic heteroleptic iridium(III) complexes have been prepared from methyl- or benzyl-substituted chelating imidazolylidene or benzimidazolylidene ligands using a Ag(I) transmetallation protocol. The synthesised iridium(III) complexes were characterised by elemental analysis, (1)H and (13)C NMR spectroscopy and the molecular structures for three complexes were determined by single crystal X-ray diffraction. A combined theoretical and experimental investigation into the spectroscopic and electrochemical properties of the series was performed in order to gain understanding into the factors influencing photoluminescence and electrochemiluminescence efficiency for these complexes, with the results compared with those of similar NHC complexes of iridium and ruthenium. The N^C coordination mode in these complexes is thought to stabilise thermally accessible non-emissive states relative to the case with analogous complexes with C^C coordinated NHC ligands, resulting in low quantum yields. As a result of this and the instability of the oxidised and reduced forms of the complexes, the electrogenerated chemiluminescence intensities for the compounds are also low, despite favourable energetics. These studies provide valuable insights into the factors that must be considered when designing new NHC-based luminescent complexes.

The rough sets feature selection for trees recognition in color aerial images using genetic algorithms

Selecting a set of features which is optimal for a given task is the problem which plays an important role in a wide variety of contexts including pattern recognition, images understanding and machine learning. The concept of reduction of the decision table based on the rough set is very useful for feature selection. In this paper, a genetic algorithm based approach is presented to search the relative reduct decision table of the rough set. This approach has the ability to accommodate multiple criteria such as accuracy and cost of classification into the feature selection process and finds the effective feature subset for texture classification . On the basis of the effective feature subset selected, this paper presents a method to extract the objects which are higher than their surroundings, such as trees or forest, in the color aerial images. The experiments results show that the feature subset selected and the method of the object extraction presented in this paper are practical and effective.

The convergent validity of two sensory processing scales used with school - age children : comparing the sensory profile and the sensory processing measure

Abstract: Aim: To investigate the convergent validity between the Sensory Profile, the Sensory Profile School Companion, and the Home and Main Classroom Forms of the Sensory Processing Measure.

Method: Thirty mothers completed the Sensory Profile and the Sensory Processing Measure - Home Form on one child each. Nineteen teachers of the same children completed the Sensory Profile School Companion and the Sensory Processing Measure - Main Classroom Form.

Results: The Sensory Profile and the Sensory Processing Measure - Home Form were significantly correlated (rho=0.86, p less-than .01). The Sensory Profile School Companion and Sensory Processing Measure - Main Classroom Form were also significantly correlated (rho=.74, p less-than .01).

Conclusion: The two sets of sensory processing scales had moderate levels of convergent validity.

Selection criteria, skill sets and competencies: what is their role in the appointment of vice-chancellors in Australian universities?

Purpose - The research presented here attempts to identify and analyse the reported selection criteria used in the appointment of Australian vice-chancellors (VCs) and to contrast this with the selection criteria actually used. Design/methodology/approach - Contemporary research into the nature, role and purpose of section criteria in appointment processes has chiefly been conducted in the private sector and across various hierarchical levels. The research is based on a PhD entitled "The recruitment and selection of vice-chancellors for Australian universities". The research for the thesis had ethics approval and involved interviews with former and incumbent chancellors, VCs, consultants, representatives of the Australian Vice-Chancellors Committee and selection panel members. Central to this research was the selection criteria and the skill bases selection criteria attempted to measure. A questionnaire was also sent to those listed above. Findings - The findings show that a matching of organisational antecedents with candidate attributes does occur. The research also highlights the key selection criteria used to appoint VCs. It also demonstrates how these key criteria are universally applied but in different orders depending upon the various foci of universities. Non-stated, but important, criteria and competencies are also discussed. Originality/value - No other research exists outlining the skill sets and competencies required by Australian VCs. It is hoped that this research will form the basis for further research and discovery into this field that we know so little about. © Emerald Group Publishing Limited.