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The Diesel Particulate NOx Reduction system (DPNR), the latest system in Toyota’s D-CAT concept, combines a new catalyst and the Low Temperature Combustion (LTC) process to simultaneously reduce particulate matter (PM) and NOx emissions from diesel vehicles.

Heteroditopic hexahomo- trioxacalix(3)arene receptors that are capable of binding an anion and a cation simultaneously in a cooperative fashion were synthesized. The structure of one of the triamide derivatives was confirmed by single-crystal X-ray dif- fraction. The binding of alkali metals at the lower rim, and the binding of anions (chloride, bromide) at the upper rim, has been investigated by using 1 H NMR titration experiments. Alkali metal binding at the lower rim controls the calix cavity. Li + -ion binding to the lower rim can improve the binding ability of anions at the upper rim amide moiety by a factor of 15, thus suggesting a strong positive allosteric effect for anion recognition. However, when a Na + cation is bound to the ionophoric site on the lower rim, the calix cavity is changed from a "flat- tened cone" to a more-upright form, which is favored for intramolecular hy- drogen bonding between the neighbor- ing NH and C=O groups; this change can block the inclusion of anions onto the amide moiety at the upper rim, which strongly suggests a negative allo- steric effect of Na + -ion binding, which controls the cooperative recognition system.