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The aim of the study is to investigate a new formulation, based on dioctadecyldimethyl ammonium-bromide (QA) and riboflavin (RF), combining antimicrobial activities and protease inhibitory properties with collagen crosslinking without interference to bonding capabilities in a rabbit model. Quaternary ammonium riboflavin (QARF) experimental adhesives modified with dioctadecyldimethyl ammonium-bromide and riboflavin were bonded (0.5/1.0/2.0%) to rabbit dentin to investigate for pulpal-histology, interfacial-morphology, transmission electron microscopy, mechanical properties, collagen crosslinking, micro-Raman analysis, antimicrobial, and anti-protease activities. Collagen type-I molecules were generated using molecular-docking. Odontoblasts appeared with normal histology, were seen in controls with no inflammatory cells detected in 0.5% specimens at day 7 and mild inflammatory response at day 30. In QARF 2.0%, inflammatory cells were not detected at day 7 and 30 (p < .05). Dentinal tubules are seen with intact collagen surface in 1% specimens. Resin penetrated inside 1% adhesive specimens with few irregularly funnel-shaped tags. Transmission electron microscopy showed thinner collagen in all specimens except 1% QARF specimens. Biofilms were influenced by QARF adhesives. Elastic moduli were significantly higher in 1.0% and 2.0% QARF adhesive specimens with a significant increase in total crosslinks. Stable amide groups with anti-protease activity was observed in QARF groups. Charged residues were seen in the triple helix hCOL3A1, Gly489-Gly510 after stabilisation with formulation. The 1% QARF modified adhesives improved biochemical and biomechanical properties of rabbit dentin.

This paper describes an investigation of the adsorption of CH 3 I on a KI-impregnated carbon and the influence of competitive adsorption on the process. A gravimetric method was used to study the equilibrium capacity and kinetics for the adsorption of CO 2 and CH 3 I in the presence of He, and CH 3 I in the presence of CO 2 on the carbon. The results of these experiments were compared with those obtained from measurements carried out using a McBain spring apparatus to obtain the equilibrium uptake of CH 3 I vapour on the KI-impregnated carbon at 293 K. The adsorption kinetic results covering the range 275–333 K show that the rates of adsorption are only weakly dependent on the temperature. The apparent activation energies for adsorption of CO 2 and CH 3 I in the presence of He, and CH 3 I in the presence of CO 2 were 20.0 ± 1.1, 6.5 ± 0.3 and 10.0 ± 0.5 kJ mol −1 , respectively. The rates of adsorption of CH 3 I in the presence of CO 2 were about half the corresponding rate of the adsorption of CH 3 I in the presence of He. However, the equilibrium capacities were very similar in both cases. Adsorption experiments carried out over a CH 3 I partial pressure range, 3.08–38.5 kPa in CO 2 showed that the initial adsorption rate constant was linearly dependent on the CH 3 I concentration. The results are discussed in terms of competitive adsorption in the CH 3 I-CO 2 system.

A 30 kW pilot-scale rotating retort combustor was designed to burn a range of coking coals and to be capable of operating with different primary and secondary air distributions. By improving the air supply arrangements it was possible to increase the peak combustion efficiency from 80 to 95%. The NOx emission was in the range 61–258 ppm and was subject to the well-known temperature effect. Total hydrocarbon emission levels (C1-C7) were significantly reduced to < 230 ppm with the improved air supply arrangements. Investigations on the effect of tilt and bed depth also showed a reduction in the C1-C7 emission to < 15 ppm at the highest bed depth. Smoke levels were below Ringelmann 2 for all operating conditions.