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This paper deals with the influences of pH, acidity and ionic intensity of the solutions on the resonance Rayleigh scattering spectra and fluorescence spectra of humic acid. When the pH value is low and the acidity and ionic intensity are high, the resonance Rayleigh spectra and fluorescence spectra both show a tendency of increasing, though the former’s intensity is much higher. In combination with the transmission electron microscope data, the factors leading to the occurrence and enhancement of the resonance Rayleigh scattering spectra of humic acid were explored. It is considered that particle enlargement caused by aggregation, the increase of heterogeneity, the increase of hydrophobility, the formation of interface, etc., are the factors leading to the occurrence and enhancement of the resonance Rayleigh scattering spectra of humic acid. As the intensity of the resonance Rayleigh scattering spectra of humic acid is much higher, resonance Rayleigh scattering spectroscopy can be used as a newly developed spectrum technology, which is more sensitive and simpler, to study humic acid and its complicated behaviors.

Using a combination of accelerator-based ion beam methods we have analysed PM2.5 particulates for a suite of 21 species (H, C, Na, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Pb) to evaluate the contribution to Sydney (New South Wales, Australia) air associated with the introduction of MMT as a replacement for lead. MMT was discontinued in 2004. Teflon filters representing continuous sampling for a 7 year period from 1998 to 2004 were analysed from two sites: one from Mascot, a suburb close to the Central Business District [CBD ( n = 718 )] and a high trafficked area, and the other, a relatively rural (background) setting at Richmond, ∼20 km west of the CBD ( n = 730 ). Manganese concentrations in air at the background site increased from a mean of 1.5–1.6 ng m−3 to less than 2 ng m−3 at the time of greatest MMT use whereas those at Mascot increased from about 2 to 5 ng m−3. From the maximum values, the Mn showed a steady decrease at both sites concomitant with the decreasing use of MMT. Lead concentrations in air at both sites decreased from 1998 onwards, concomitant with the phase out of leaded gasoline, attained in 2002. Employing previously determined elemental signatures it was possible to adjust effects from season along with auto emissions and soil. A high correlation was obtained for the relationship between Mn in air and lead replacement gasoline use (R2 0.83) and an improved correlation for Mn/ Al+Si+K and lead replacement gasoline use (R2 0.93). In addition, using Mn concentrations normalized to background values of Al+Si+K or Ti to account for the lithogenically derived Mn, the proportion of anthropogenic Mn was approximately 70%. The changes for Mn and Pb detected in the particulates are attributed to the before-during-after use of MMT and decreasing use of lead in gasoline. The values measured in Sydney air are well below the reference concentration of 50 ng Mn m−3. The incremental increases in air, however, are larger than expected given the limited use of MMT only in lead replacement gasoline and high quality monitoring should be undertaken in countries where MMT is used in all gasoline.

In this paper, based on the adsorptive kinetic experiments and interfacial chemistry experiments, the adsorption mechanism and the factors influencing the adsorption of humus by HS-12 resin have been studied. Humus in the water of the Changjiang estuary was extracted by the application of this method. At the same time, humus in the sediments, being measured with the weighing method, was characterized by UV-VIS and IR spectra. The results showed that (1) the maximum adsorption capacity by using HS-12 resin could be obtained at pH=3; (2) the exchange velocity was controlled by the particle diffusion mechanism; (3) the adsorption of humus by HS-12 resin was a characteristic adsorption because the IEP (isoelectric point) of the HS-12 resin had been altered through the process; and (4) the average concentration of humus in water was 0.28 mg/L, while in the sediments it was about 2.74 mg/g.