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Organoindium compounds of redox active 1,2‐benzenedithiolate and 2‐amidobenzenethiolate ligands were synthesized and tested for reactivity against mild oxidants. The reaction of Me3In and (NCN)InMe2 [NCN=2,6‐bis(dimethylaminomethy)phenyl] with 3,4‐toluenedithiol (H2tdt) at room temperature afforded [MeIn(tdt)(py)]2 (1) and (NCN)In(tdt) (2), respectively. A similar reaction of Me3In with 2‐aminobenzenethiol (H2abt) in toluene under reflux afforded [MeIn(abt)(py)]2 (3). The reaction of (NCN)InCl2 with one equivalent of Li2(abt) or two equivalents of Li(Habt) afforded the compounds [(NCN)In(abt)]⋅LiCl(thf)2 (4⋅LiCl(thf)2) and (NCN)In(Habt)2 (5), respectively. The X‐ray crystal structures of 1 and 3 are similar and show dimeric structures via μ‐S‐(tdt) and μ‐N‐(abt) ligands, respectively. Compounds 2 and 4 possess similar monomeric structures and tridentate NCN pincer ligands. DFT computational studies have been used to rationalize the observed solid‐state structures and discern the potential reactivity of compounds 1–4 against oxidants. The reaction of 1 and 2 with excess iodine resulted in loss of the 3,4‐toluenedithiolate ligand and the formation of the oligomeric disulfide [tdt]n, while 3 and 4 showed no reactivity under similar conditions. This contrasts the reactivity of previously reported organoindium o‐amidophenolate complexes which undergo oxidative addition of iodine to afford ligand‐centered radical species. [ABSTRACT FROM AUTHOR]

The objective of this research is to develop a microelectromechanical system (MEMS)-based intelligent hybrid Biaxial Strain Transducer (BiAST) sensor for predicting railroad fatigue life based on strain history. The developed BiAST prototype was deployed to collect real-time strain data from the full-scale test track at the Transportation Technology Center (TTCI), near Pueblo, Colorado. The collected strain data were analyzed using the 'Binner' fatigue analysis program for counting the load cycles and estimating the fatigue life of a rail structure. Field-testing results of the BiAST were used to evaluate the BiAST prototype with respect to its repeatability, accuracy, and hybridization. BiAST was effective in detecting the dynamic response of a particular wheel and spurious overload events. BiAST can be used to detect passing wheels, train speed, and track condition. CE Database subject headings: Transducers; Evaluation; Fatigue life.

There is no single socialist model because the traditional socialist models focus on a single model which focuses on state ownership and a highly- integrated system of central planning. On the other hand, the new socialist models focus on various ownership and central planning patterns, resulting in different economic models. For social democracy to survive, it must prove itself capable of being adaptable and dynamic.

Three types of processes are examined, namely, monomer loading, polymerization and removal of unreacted monomers. It is observed that these processes are affected by the presence of oxygen and are photosensitive. A variety of oxidizing agents are used to effect polymerization including Fe(super 3+), H2O2, ammonium persulfate, and UV irradiation.

This study uses path analysis to examine data for 304 towns and villages in Saskatchewan for 1971-1986, and assesses: (1) how population size affects change in the elderly population; and (2) how such change influences the diversity of local services and the volume of retail sales. Consistent with central place theory, the gains and losses in the elderly population in small towns are found to be positively related to the relative population size of the towns. In turn, local retail sales and the functional diversity of towns are largely dependent upon change in the elderly population, although the distance from a city and local economic conditions also affect services and retail sales. The study concludes that services and retail business in rural Saskatchewan are largely sustained by the elderly population, the decline of which may signify the demise of the economies of many small towns.

Core 86027-144 (74°15.56′ N, 91°14.21′ W) represents a rare, continuous record of Late Pleistocene to Holocene sediments from High Arctic Canada extending from the end of the Last Glaciation. Based on microfossils (dinocysts, non-pollen palynomorphs, benthic and planktonic foraminifera), foraminiferal δ18O and δ13C, and sedimentology, seven palaeoenvironmental zones were identified. Zone I (>10.8 cal. ka BP) records deglaciation, ice-sheet destabilization, float-off and subsequent break-up. Zone II ( c. 10.8-10.4 cal. ka BP) shows ice-proximal to ice-distal glaciomarine conditions, interrupted by pervasive land-fast sea-ice marked by a hiatus in coarse sediment deposition. Significant biological activity starts in Zone III (10.4-9.9 cal. ka BP), where planktonic foraminifera ( N eogloboquadrina pachyderma) suggest early oceanic throughflow. Surface waters flowed NW-SE; however, the deep-water origin remains unclear (potentially NW Arctic Ocean or Baffin Bay). Postglacial amelioration (open-water season greater than present) in Zone IV (9.9-7.8 cal. ka BP) perhaps corresponds to the regional 'Holocene Thermal Maximum' previously proposed. A transitional period (Zone V; 7.8-6.7 cal. ka BP) of rapid environmental change fluctuating on a scale not observed today is marked by increasing sea-ice and reduced oceanic influence. This probably signals the exclusion of deeper Atlantic water owing to the glacio-isostatic shallowing of inter-island sills, coupled with generally cooling climate. Conditions analogous to those at present, with increased sea-ice and modern microfossil assemblages, commence at c. 6.7 cal. ka BP (zones VI- VII). Although climate ultimately forces long-term environmental trends, core 86027-144 data imply that regional dynamics, especially changes in sea-level, exert a significant control on marine conditions throughout the Canadian Arctic Archipelago. [ABSTRACT FROM AUTHOR]

Nonprecious metal catalysts (NPMC) for the oxygen reduction reaction were prepared by surface modification of a carbon black with 5,6-diamino-1,10-phenanthroline through diazonium and benzimidazole coupling chemistry. Both methodologies covalently attach 1,10-phenanthroline to the surface. Oxygen-free cyclic voltammograms (CV) obtained for these modified carbons showed a clearly defined redox peak at ca. 650 mV versus normal hydrogen electrode, which we attribute to phenanthroline-type groups on the carbon surface. Introduction of Fe and subsequent pyrolysis at 700°C under a NH3/N2 atmosphere yielded catalysts that were highly active toward the oxygen reduction reaction. The redox peak at 650 mV was present in the oxygen-free CVs for the most active catalysts, though less intense. Nevertheless, this indicates the presence pyridinic-type active sites in the heat treated catalysts and may be a useful tool in the study of NPMC. [ABSTRACT FROM AUTHOR]

Discusses the occupation of Hudson Strait by late Quaternary ice streams. Importance of Hudson Strait as the major source for sediments associated with the North Atlantic Heinrich events; Glacial erosion of the Paleozoic outcrop on the floor of Hudson Strait and Ungava Bay; Sediment transport.

This paper describes the design, analysis and characterization of a prototype active column that applies distributed MEMS technology to the active stabilization of a buckling compressive member. The axial load bearing capacity of structural members can be increased by actively controlling the dynamic instability of buckling. Effective active stabilization is dependent on three primary factors: sensor precision, actuator authority, and control system bandwidth. A networked array of MEMS sensors, filamentary PZT actuators, and recently developed optimal control strategies are combined to demonstrate active control of an inherently unstable column. The active system, designed and simulated using finite element and optimization methods, stabilizes an experimental column for compressive axial loads up to 2.9 times the critical buckling load. Additionally, the system is stable for all loads in the range from tension to this maximum compressive axial load. [ABSTRACT FROM PUBLISHER]

University and college criminology courses attract a very large number of Canadian students many of whom are exposed to critical perspectives. In this article we explain the major influences on Canadian radical criminological pedagogy. We also point out the strengths and limitations of this approach, and propose several suggestions for improvement. [ABSTRACT FROM PUBLISHER]

The Canadian Urban Victimization Survey (CUVS) has made an important contribution to the development of victimology in Canada. This research has major limitations that preclude it from providing an adequate understanding of the gender, class, and ethnic dimensions of criminal victimization. This article argues that British left realist survey technology can be productively employed in a Canadian program of local crime survey research to produce a more detailed description of patterns of victimization, its impact, and control. [ABSTRACT FROM PUBLISHER]

A pyrazine bridged ruthenium/palladium bimetallic photocatalyst with peripheral 4,4′-dicarboxyethyl-2,2′-bipyridine ligands, EtOOC-RuPd, is reported, together with its 2,2′-bipyridine analogue. Upon irradiation with visible light, EtOOC-RuPdcatalyses the production of hydrogen gas whereas the complex RuPddoes not. [ABSTRACT FROM AUTHOR]

An introduction to the issue is presented wherein the editor compares British criminology to that of Canadian criminology, the struggle for justice, and the consideration of the "Journal of Human Justice" as a vehicle of critical pedagogy.

A letter to the editor is presented in response to the article "Nash in Najaf: Game Theory and Its Applicability to the Iraqi Conflict," by Hank Brightman in the Fall 2007 issue.

The title compound, [Ru(C 19 H 13 N 5 ) 2 ](PF 6 ) 2 ·3C 4 H 10 O, was obtained from the reaction of Ru(bimpy)Cl 3 [bimpy is 2,6-bis-(1 H -benzimidazol-2-yl)pyridine] and bimpy in refluxing ethanol followed by recrystallization from diethyl ether/aceto-nitrile. At 125 K the complex has ortho-rhom-bic ( Pca 2 1 ) symmetry. It is remarkable that the structure is almost centrosymmetric. However, refinement in space group Pbcn leads to disorder and definitely worse results. It is of inter-est with respect to potential catalytic reduction of CO 2 . The structure displays N-H⋯O, N-H⋯F hydrogen bonding and significant π-π stacking and C-H⋯π stacking inter-actions., (© Althubyani et al. 2024.)

The synthesis and characterisation of two terpyridine based ruthenium/palladium heteronuclear compounds are presented. The photocatalytic behaviour of the Ru/Pd complex containing the linear 2,2':5',2''-terpyridine bridge (1a) and its analogue the non-linear 2,2':6',2''-terpyridine bridge (2a) are compared together with the respective mononuclear complexes 1 and 2. Irradiation of 1a with visible light (e.g., 470 nm) results in the photocatalytic generation of dihydrogen gas. Photocatalysis was not observed with complex 2a by contrast. A comparison with the photocatalytic behaviour of the precursors 1 and 2 indicates, that while for 1a the photocatalysis is an intramolecular process, for the mononuclear precursors it is intermolecular. The photophysical and electrochemical properties of the mono- and heterobinuclear compounds are compared. Raman spectroscopy and DFT calculations indicate that there are substantial differences in the nature of the lowest energy (3)MLCT states of 1a and 2a, from which the contrasting photocatalytic activities of the complexes can be understood.

A pyrazine bridged ruthenium/palladium bimetallic photocatalyst with peripheral 4,4'-dicarboxyethyl-2,2'-bipyridine ligands, EtOOC-RuPd, is reported, together with its 2,2'-bipyridine analogue. Upon irradiation with visible light, EtOOC-RuPd catalyses the production of hydrogen gas whereas the complex RuPd does not.