Field blanks (bQF) and backup filters (quartz-fiber behind quartz-fiber filter; QBQ) have been adopted by US long-term air quality monitoring networks to estimate PM_2.5 organic carbon (OC) sampling artifacts. This study documents bQF and QBQ carbon levels for the: 1) Interagency Monitoring of Protected Visual Environments (IMPROVE); 2) Speciation Trends Network (STN; part of the Chemical Speciation Network [CSN]); and 3) Southeastern Aerosol Research and Characterization (SEARCH) networks and examines the similarities/differences associated with network-specific sampling protocols. A higher IMPROVE sample volume and smaller filter deposit area results in PM_2.5 areal density (μg/cm² on filter) 3–11 times those of STN/CSN and SEARCH samples for the same ambient PM_2.5 concentrations, thus reducing the relative contribution of sampling artifacts from passive OC adsorption. A relatively short (1–15 min) passive exposure period of STN/CSN and SEARCH bQF OC (0.8–1 μg/cm²) underestimates positive and negative OC artifacts resulting from passive adsorption or evaporation of semi-volatile organic compounds on quartz-fiber filters. This is supported by low STN/CSN and SEARCH bQF levels and lack of temporal or spatial variability among the sites within the networks. With a much longer period, ~7 days of ambient passive exposure, average IMPROVE bQF and QBQ OC are comparable (2.4±0.5 and 3.1±0.8 μg/cm², respectively) and more than twice levels found in the STN/CSN and SEARCH networks. Sampling artifacts in STN/CSN were estimated from collocated IMPROVE samples based on linear regression. At six of the eight collocated sites in this study, STN/CSN bQFs underestimated OC artifacts by 11–34%. Using a preceding organic denuder in the SEARCH network minimized passive adsorption on QBQ, but OC on QBQ may not be attributed entirely to the negative sampling artifact (e.g., evaporated or volatilized OC from the front filter deposits after sample collection)

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Open innovation has generally been seen as an important driver of improved efficiency and effectiveness in product and/or service innovation. This chapter extends these focal areas to include process innovations -generally organizational innovations aimed at improving the nature of organizational value adding and factor transformative systems. In this study we assess the impact of openness on products, services and processes, drawing on a large-scale sample of Australian firms. We find that open innovation models are useful for firms seeking to innovate in processes, as well as products and services. However, we find that openness to external information sources may, after a time, lead to decreasing marginal returns as measured by innovation performance. We also observe that, within our sample, the proposed complementarities between internal and external knowledge sources are generally only evident as precursors to the introduction of new products and services, and may not be as beneficial in stimulating process innovations. We also show that investment in absorptive capacity has a declining marginal effect on the innovation performance of new processes, but not on the introduction of new products and services.

The chemical composition of PM 2:5 was investigated at four sites (Rubidoux, CA, Phoenix, AZ, Philadelphia, PA, and Research Triangle Park, NC) in January and February of 1999. Three samplers were used to determine both the overall mass and the chemical composition of the aerosol. Te on lters were weighed for total mass. Ions were analyzed using ion chromatography. Elements were determined using X-ray uorescence. Organic and elemental carbon were measured using a thermo-optical method. At all of the sites, reconstructed mass was observed to be greater than or equal to the measured mass. Good ionic balance was found for ammonium, nitrate, and sulfate at each of the sites. Overall, the chemical composition of the aerosol for each site was in good agreement with the expected composition based upon previous studies, with the exception of relatively high nitrate contribution to the total mass at Philadelphia. Good agreement was found between the predicted amount of sulfate by XRF analysis of sulfur and the sulfate measured by ion chromatography. As expected, sulfate was a more important contributor to the total mass at the East Coast sites. Nitrate contributed more to the total mass at the West Coast sites and was an important factor in the highest observed mass concentration at Rubidoux. Te on lters appear to lose nitrate to a greater extent than heat-treated quartz ber lters. Organic carbon was also found to be the largest part of the aerosol mass on minimum days for all sites and a signi cant portion of the mass on other days with 25 -50% of the total mass at all of the sites. At three of the sites, organic carbon (OC) collected on denuded lters was less than that found on nondenuded samples, indicating an absorptive artifact on the quartz ber lters. It was also found that the crustal component to PM 2:5 was highest at Phoenix. PM 2:5 was also found to contribute signi cantly to the PM 10 particle mass at all the sites.

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