Single particle diversity and mixing state measurements

A newly developed framework for quantifying aerosol particle diversity and mixing state based on information-theoretic entropy is applied for the first time to single particle mass spectrometry field data. Single particle mass fraction estimates for black carbon, organic aerosol, ammonium, nitrate and sulfate, derived using single particle mass spectrometer, aerosol mass spectrometer and multi-angle absorption photometer measurements are used to calculate single particle species diversity (Di). The average single particle species diversity (Dα) is then related to the species diversity of the bulk population (Dγ) to derive a mixing state index value (χ) at hourly resolution. The mixing state index is a single parameter representation of how internally/externally mixed a particle population is at a given time. The index describes a continuum, with values of 0 and 100% representing fully external and internal mixing, respectively. This framework was applied to data collected as part of the MEGAPOLI winter campaign in Paris, France, 2010. Di values are low (∼ 2) for fresh traffic and wood-burning particles that contain high mass fractions of black carbon and organic aerosol but low mass fractions of inorganic ions. Conversely, Di values are higher (∼ 4) for aged carbonaceous particles containing similar mass fractions of black carbon, organic aerosol, ammonium, nitrate and sulfate. Aerosol in Paris is estimated to be 59% internally mixed in the size range 150-1067 nm, and mixing state is dependent both upon time of day and air mass origin. Daytime primary emissions associated with vehicular traffic and wood-burning result in low χ values, while enhanced condensation of ammonium nitrate on existing particles at night leads to higher χ values. Advection of particles from continental Europe containing ammonium, nitrate and sulfate leads to increases in Dα, Dγ and χ. The mixing state index represents a useful metric by which to compare and contrast ambient particle mixing state at other locations globally.

Cork’s international trade during the first industrial revolution

This thesis explores the impact international trade and commercial agreements had on the economic and industrial development of Cork during the first industrial revolution. From the Act of Union onwards Cork moved from a region where trade became increasingly reliant on Britain at the expense of trade that had been cultivated over the eighteenth century with the Americas and Europe. The legislative underpinnings of Cork’s trade is the focus of this research and how this changed after the Act of Union. It begins by examining the transatlantic trade of Cork city and the issues faced in the West Indies trade due to the growth of the United States. It will also consider the impact of the Napoleonic Wars on Cork’s trade with both the Americas and continental Europe. The conclusion of the Napoleonic Wars saw the United Kingdom negotiate treaties and agreements that would have a direct impact upon Cork’s merchants. This thesis will address the degree to which the mercantile community in Cork were able to influence policy that directly impacted upon their trade networks. It will then examine the trade between Cork and the United Kingdom and assess the impact of the Union on the ability of Cork’s merchants to affect political change. The operation of the Committee of Merchants in Cork is detailed and their responses to the changing nature of international trade. The thesis finishes by examining the underdevelopment of Cork’s transportation networks. This work will place Cork’s international trade in both its national and international context and argues that Cork’s mercantile community were overly reliant on protectionist legislation to further Cork’s trade as opposed to investment in industrial development. Volumetric data on the trade of Cork city has been transcribed and made available in a relational database to support the arguments made in this thesis and to facilitate future research on this subject. This database is accessible at http://modernirishvenice.com/.