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The novel metal-catalyzed cross-coupling reaction of indium organometallics with organic electrophiles is described. Triorganoindium compounds (R(3)In) containing alkyl, vinyl, aryl, and alkynyl groups are efficiently prepared from the corresponding lithium or magnesium organometallics by reaction with indium trichloride. The cross-coupling reaction of R(3)In with aryl halides and pseudohalides (iodide 2, bromide 5, and triflate 4), vinyl triflates, benzyl bromides, and acid chlorides proceeds under palladium catalysis in excellent yields and with high chemoselectivity. Indium organometallics also react with aryl chlorides as under nickel catalysis. In the cross-coupling reaction the triorganoindium compounds transfer, in a clear example of atom economy, all three of the organic groups attached to the metal, as shown by the necessity of using only 34 mol % of indium. The feasibility of using R(3)In in reactions with different electrophiles, along with the high yields and chemoselectivities obtained, reveals indium organometallics to be useful alternatives to other organometallics in cross-coupling reactions.

A laboratory study of the use of recycled concrete aggregates (RCA) from construction and demolition waste (CDW) in hot-mix asphalt (HMA) for base courses in pavements was conducted. HMA mixes containing 0%, 5%, 10%, 20% and 30% RCA in place of natural aggregate were evaluated. The Marshall mix design procedure was used to develop the mixes.To improve the moisture sensitivity of the mixes, they were cured in an oven for 4 hours. The results indicated that the mixes comply with Spanish moisture damage specifications. The mechanical properties (stiffness, permanent deformation and fatigue) of the mixtures were studied. The mixtures exhibited good engineering properties. Although HMA with RCA requires further investigation, the results from this study were very promising.

This article evaluates the possibility of designing hot asphalt mix road pavements using Construction and Demolition Waste as coarse recycled aggregates. The percentages of recycled aggregates used in the mixtures were: 0%, 20%, 40% and 60%. Cement and lime were used as fillers. The mixtures made with coarse recycled aggregates complied with the Marshall technical specifications for low volume roads. The mixtures also showed good resistance to permanent deformation evaluated by means of wheel tracking tests. Nevertheless, the mixtures made with RA may have insufficient durability due to their high susceptibility to water action which was evaluated using stripping tests.

This paper analyses the effect of water on the durability of hot asphalt mixtures made with recycled aggregates from construction and demolition debris. Indirect tensile stress tests were carried out to evaluate stripping behaviour. The mixtures tested were fabricated with 0, 20, 40 and 60% recycled aggregates. Two types of natural aggregates were used: schist and calcite dolomite. An increase in the percentage of recycled aggregates was found to produce a decrease in the tensile stress ratio of the hot asphalt mixtures. To study this phenomenon, two and three factor analyses of variance (ANOVA) were performed with indirect tensile stress being used as the dependent variable. The factors studied were the percentage of recycled aggregates (0, 20, 40 and 60%), the moisture state (dry, wet) and the type of natural aggregate (schist, calcite). On the basis of the ANOVA results, it was found that the most important factor affecting resistance was the moisture state (dry, wet) of the specimens. The percentage of recycled aggregate also affected indirect tensile stress, especially in the dry state. The type of natural aggregate did not have a significant effect on indirect tensile stress. The hot asphalt mixture specimens made with different percentages of recycled aggregates from construction and demolition debris and of natural quarry aggregates showed poor stripping behaviour. This stripping behaviour can be related to both the poor adhesion of the recycled aggregates and the high absorption of the mortar of cement adhered to them.

The synthesis of the first C60-based donor−acceptor (D−A) systems (12a−c) in which the C60 core is covalently linked to strong, highly conjugated π-electron donors derived of tetrathiafulvalene (TTF) with p-quinodimethane structure has been carried out by cyclization with azomethine ylides following Prato's procedure. The synthetic strategy requires the preparation of the novel formyl-substituted π-extended donors which, in turn, are prepared in a multistep synthetic procedure by reaction of 2-formyl-9,10-anthraquinone (6) with the appropriately substituted phosphonate esters (8). Semiempirical PM3 calculations predict a geometry highly distorted from planarity for the donor fragment and a most stable conformation in which both 1,3-dithiole rings are far away from the [60]fullerene surface. The redox properties were determined by cyclic voltammetry in solution and reveal the presence of four cathodically shifted reduction waves, relative to C60 and corresponding to the C60 core, and a two-electron single oxidation wave to form stable dication species of the π-extended donor units. Magnetic susceptibility measurements clearly indicate a paramagnetic behavior in the solid state, and a remarkable conductivity is observed for these single component organic compounds.

h i g h l i g h t sRecycled concrete aggregates (RCA) have poor quality than natural aggregates. A review on the properties of hot-mix asphalt (HMA) with RCA is conducted. Most studies report a high stripping potential of these mixtures. Several treatments help mitigate its unsatisfactory moisture damage resistance. Test stretches of HMA with RCA exhibited good performance. a b s t r a c tRecycled concrete aggregates (RCA) appear to be suitable materials to use in hot-mix asphalt (HMA) for flexible road pavements. However, the poor quality of RCA results in different engineering properties of an HMA using RCA compared to mixtures composed of natural aggregates. This paper presents a review on the properties of HMA with RCA. Varied laboratory results were obtained, likely because of the heterogeneous nature and origin of the RCA. Nevertheless, a majority of the studies report a high stripping potential of RCA mixtures. Several treatments help mitigate this problem. Additionally, select test stretches of the RCA mixture exhibited good performance.

Novel pi-extended tetrathiafulvalene (exTTF)-based donor acceptor hybrids-dyads and triads-have been synthesized following a multistep synthetic procedure. Cyclic voltammetry and absorption spectroscopy, conducted in room temperature solutions, reveal features that are identical to the sum of the separate donor and acceptor moieties. Steady-state and time-resolved photolytic techniques confirm that upon photoexcitation of the fullerene chromophore, rapid (1.25 x 10(10) s(-1)) and efficient (67 %) charge separation leads to long-lived, charge-separated radical pairs. Typical lifetimes for the dyad ensembles range between 54 and 460 ns, with the longer values found in more polar solvents. This indicates that the dynamics are located in the 'normal region' of the Marcus curve. In the triads, subsequent charge shifts transform the adjacent radical pair into the distant radical pair, for which we determined lifetimes of up to 111 micros in DMF-values never previously accomplished in molecular triads. In the final charge-separated state, large donor-acceptor separation (center-to-center distances: approximately 30 A) minimizes the coupling between reduced acceptor and oxidized donor. Analysis of the charge recombination kinetics shows that a stepwise mechanism accounts for the unusually long lifetimes.