[1] Following the examination and evaluation of 12 nucleation parameterizations presented in part 1, 11 of them representing binary, ternary, kinetic, and cluster-activated nucleation theories are evaluated in the U.S. Environmental Protection Agency Community Multiscale Air Quality (CMAQ) modeling system version 4.4. The 12-28 June 1999 Southern Oxidants Study episode is selected as a testbed to evaluate simulated particulate matter (PM) number and size predictions of CMAQ with different nucleation parameterizations. The evaluation shows that simulated domain-wide maximum PM 2.5 number concentrations with different nucleation parameterizations can vary by 3 orders of magnitude. All parameterizations overpredict (by a factor of 1.4 to 1.7) the total number concentrations of accumulation-mode PM and significantly underpredict (by factors of 1.3 to 65.7) those of Aitken-mode PM, resulting in a net underprediction (by factors of 1.3 to 13.7) of the total number concentrations of PM 2.5 under a polluted urban environment at a downtown station in Atlanta. The predicted number concentrations for Aitken-mode PM at this site can vary by up to 3 orders of magnitude, and those for accumulation-mode PM can vary by up to a factor of 3.2, with the best predictions by the power law of Sihto et al. (2006) Harrington and Kreidenweis (1998) give better agreement than the remaining parameterizations. All the parameterizations fail to reproduce the observed temporal variations of PM number, volume, and surface area concentrations. The significant variation in the performance of these parameterizations is caused by their different theoretical bases, formulations, and dependence on temperature, relative humidity, and the ambient levels of H 2 SO 4 and NH 3 . The controlling processes are different for PM number, mass, and surface areas. At urban/rural locations, some PM processes (e.g., homogeneous nucleation) and/or vertical transport may dominate the production of PM 2.5 number, and emissions, or PM processes, or vertical transport or their combinations may dominate the production of PM 2.5 mass and surface area. Dry deposition or some PM processes such as coagulation may dominate PM 2.5 number loss, and horizontal and vertical transport, and cloud processes (e.g., cloud scavenging and wet deposition) may dominate the loss of PM 2.5 mass and surface area concentrations. Sensitivity simulations show that the PM number and size distribution predictions are most sensitive to prescribed emission fractions of Aitken and accumulation-mode PM and the assumed initial PM size distribution, in addition to different nucleation parameterizations.

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Differential Thermal Analysis(DTA) and Differential scanning calorimetry (DSC) were used to study the effect of Bamboo Powder(BP) on the curing behavior of two types of liquefied bamboo-based resol resin(PBF). DTA analysis shows that the addition of bamboo powder to the PBF resin leads to low temperature and broad peaks in the DTA curves. It also accelerates the addition reaction in the curing process of PBF resin and reduced the peak temperature, activation energies for PBF resin . Bamboo Powder reduced the activation energies for resins because the bamboo powder maybe had selfcatalysis effect. The lowest activation energy for a PBF resin probably appeared about at pH 11.0 under alkaline conditions.

In this paper, effect of acid curing agent on the foaming of liquefied bamboo-based resol resin (PBF) were studied. The research result indicated that the optimal acid curing agent were mixture of p-toluenesulfonic acid and H3PO4, curing of PBF resol resin was analysized in detail and computer-aided software was applied for calculating thermodynamics characteristic of foaming process so that integrative assistantwas controlled better. Its apparent activation energy was 1.226 kJ·mol-1. The PBF foam showed satisfactory densities and compressive properties.

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